毕业设计的英文翻译
毕业设计中英文翻译【范本模板】
英文The road (highway)The road is one kind of linear construction used for travel。
It is made of the roadbed，the road surface, the bridge, the culvert and the tunnel. In addition, it also has the crossing of lines, the protective project and the traffic engineering and the route facility。
The roadbed is the base of road surface, road shoulder，side slope, side ditch foundations. It is stone material structure, which is designed according to route's plane position .The roadbed, as the base of travel, must guarantee that it has the enough intensity and the stability that can prevent the water and other natural disaster from corroding.The road surface is the surface of road. It is single or complex structure built with mixture。
The road surface require being smooth，having enough intensity，good stability and anti—slippery function. The quality of road surface directly affects the safe, comfort and the traffic。
毕设翻译英文
轨道交通学院毕业设计（论文）外文翻译题目：列车车载的直流恒流源的设计专业电子信息工程班级10115111学号1011511137姓名赵士伟指导教师陈文2014 年3 月 3 日本文摘自：IEEE TRANSACTIONS ON INDUSTRY AND GENERAL APPLICATIONS VOL. IGA-2, NO.5 SEPT/OCT 1966Highly Regulated DC Power Supplies Abstract-The design and application of highly regulated dc power supplies present many subtle, diverse, and interesting problems. This paper discusses some of these problems (especially inconnection with medium power units) but emphasis has been placed more on circuit economics rather than on ultimate performance.Sophisticated methods and problems encountered in connection with precision reference supplies are therefore excluded. The problems discussed include the subjects of temperature coefficient,short-term drift, thermal drift, transient response degeneration caused by remote sensing, and switching preregualtor-type units and some of their performance characteristics.INTRODUCTIONANY SURVEY of the commercial de power supply field will uncover the fact that 0.01 percent regulated power supplies are standard types and can be obtained at relatively low costs. While most users of these power supplies do not require such high regulation, they never-theless get this at little extra cost for the simple reason that it costs the manufacturer very little to give him 0.01 percent instead of 0.1 percent. The performance of a power supply, however, includes other factors besides line and load regulation. This paper will discuss a few of these-namely, temperature coefficient, short-term drift, thermal drift, and transient response. Present medium power dc supplies commonly employ preregulation as a means of improving power/volume ratios and costs, but some characteristics of the power supply suffer by this approach. Some of the short-comings as well as advantages of this technology will be examined.TEMPERATURE COEFFICIENTA decade ago, most commercial power supplies were made to regulation specifications of 0.25 to 1 percent. The reference elements were gas diodes having temperature coefficients of the order of 0.01 percent [1]. Consequently, the TC (temperature coefficient) of the supply was small compared to the regulation specifications and often ignored. Today, the reference element often carries aTC specification greater than the regulation specification.While the latter may be improved considerably at little cost increase, this is not necessarily true of TC. Therefore,the use of very low TC zener diodes, matched differential amplifier stages, and low TC wire wound resistors must be analyzed carefully, if costs are to be kept low.A typical first amplifier stage is shown in Fig. 1. CRI is the reference zener diode and R, is the output adjustment potentiometer.Fig. 1. Input stage of power supply.Fig. 2. Equivalent circuit of zener reference.Let it be assumed that e3, the output of the stage, feedsadditional differential amplifiers, and under steady-state conditions e3 = 0. A variation of any of the parameters could cause the output to drift; while this is also true of the other stages, the effects are reduced by the gain of all previous stages. Consequently, the effects of other stages will be neglected. The following disculssion covers the effects of all elements having primary and secondary influences on the overall TC.Effect of R3The equivalent circuit of CRI -R3 branch is shown in Fig. 2. The zener ha's been replaced with its equivalent voltage source E/' and internal impedance R,. For high gain regulators, the input of the differential amplifier will have negligible change with variations of R3 so thatbefore and after a variation of R3 is made.If it is further assumed that IB << Iz; then from (1)Also,Eliminating I, from (2b),andNow, assuming thatthen,Equation (2b) can also be writtenThe Zener DiodeThe zener diode itself has a temperature coefficient andusually is the component that dominates the overall TCof the unit. For the circuit of Fig. 1, the TC ofthe circuit describes, in essence, the portion of the regulator TC contributed by the zener. If the bridge circuit shown in Fig. 1 were used in conjunction with a dropping resistor so that only a portion of the output voltage appeared across the bridge circuit shown, the TC of the unit and the zener would be different. Since the characteristic of zeners is so well known and so well described in the literature, a discussion will not be given here [2].Variation of Base-Emitter VoltagesNot only do the values of V,, of the differential am-plifier fail to match, but their differentials with tem perature also fail to match. This should not, however,suggest that matched pairs are required. The true reference voltage of Fig. 1 is not the value E,, but E, + (Vie, -Vbe2)-Since, for most practical applicatioinsthe TC of the reference will be the TC of the zener plusConsidering that it is difficult to obtain matched pairs that have differentials as poor as 50 V/°C, it becomes rather apparent that, in most cases, a matched pair bought specifically for TC may be overdesigning.Example 2: A standard available low-cost matched pair laims 30AV/°C. In conjunction with a 1N752, the ontribution to the overall TC would beTests, performed by the author on thirteen standard germanium signal transistors in the vicinity of room temperature and at a collector current level of 3 mA,indicated that it is reasonable to expect that 90 to 95 percent of the units would have a base-emitter voltage variation of -2.1 to -2.4 mV/°C. Spreads of this magnitude have also been verified by others (e.g., Steiger[3]). The worst matching of transistors led to less than 400 ,V/°C differential. In conjunction with a 1N752,even this would give a TC of better than 0.007%/0C.Variation of Base CurrentsThe base current of the transistors is given byA variation of this current causes a variation in signal voltage at the input to the differential amplifier due to finite source impedances. Matching source impedances is not particularly desirable, since it reduces the gain of the system and requires that transistors matched for I,o and A be used. Hunter [4 ] states that the TC of a is in the range of +0.2%/0C to -0.2%7/'C and that 1,, may be approximated bywhere Ao is the value at To.β is also temperature dependent and Steiger [3] experimentally determined the variation to be from about 0.5%/°C to 0.9%/0C.And，Fig. 3. Input circuit of Q2.The current AIB flows through the source impedance per Fig. 3. The drops in the resistance string, however, are subject to the constraint that EB (and AEB) are determined by the zener voltage and the base-emitter drops of Q1 and Q2. Consequently, if in going from temperature T1to T2 a change AEB occurs,The change in output voltage isAndExample 3: For Q2 (at 25°C)(see Example 1)∴Variation of R,The effects of a variation of the TC between RIA and RIB is sufficiently self-evident so that a discussion of the contribution is not included.SHORT-TERM DRIFTThe short-term drift of a supply is defined by the National Electrical Manufacturers Association (NEMA) as "a change in output over a period of time, which change is unrelated to input, environment, or load [5]."Much of the material described in the section on temperature coefficient is applicable here as well. It has been determined experimentally, however, that thermal air drafts in and near thevicinity ofthe powersupplycontributesenormouslyto theshort-termcharacteristics. Thecooling effects of moving air are quite well known, but it is not often recognized that even extremely slow air movements over such devices as zeners and transistors cause the junction temperature of these devices to change rapidly. If the TC of the supply is large compared to the regulation, then large variations in the output will be observed. Units having low TC's achieved by compensation-that is, by canceling out the effects of some omponents by equal and opposite effects of others may still be plagued by these drafts due to the difference in thermal time constants of the elements.Oftentimes, a matched transistor differential amplifier in a common envelope is used for the first amplifier just to equalize and eliminate the difference in cooling effects between the junctions. Approximations to this method include cementing or holding the transistors together, imbedding the transistors in a common metal block, etc. Excellent results were achieved by the author by placing the input stage and zener reference in a separate enclosure. This construction is shown in Fig. 4. The improvement in drift obtained by means of the addition of the metal cover is demonstrated dramatically in Fig. 5.Fig. 5. Short-term drift of a power supply similar to the one shown in Fig. 4 with and without protective covers. The unit was operated without the cover until time tl, when the cover was attached. The initial voltage change following t, is due to a temperaturerise inside the box.Fig. 5. Short-term drift of a power supply similar to the one shown n Fig. 4 withand without protective covers. The unit was operated without the cover until time tl, when the cover was attached. The initial voltage change following t, is due to atemperature rise inside the box.If potentiometers are used in the supply for output adjustment (e.g., RI), care should be used in choosing the value and design. Variations of the contact resistance can cause drift. It is not always necessary, however, to resort to the expense of high-resolution multiturn precision units to obtain low drift. A reduction in range of adjustment, use of low-resistance alloys and low-resolution units which permit the contact arm to rest firmly between turns, may be just as satisfactory. Of course, other considerations should include the ability of both the arms and the wire to resist corrosion. Silicone greases are helpful here. Periodic movement of contact arms has been found helpful in "healing" corroded elements.THERMAL DRIFTNEMA defines thermal drift as "a change in output over a period of time, due to changes in internal ambient temperatures not normally related to environmental changes. Thermal drift is usually associated with changes in line voltage and/or load changes [5]."Thermal drift, therefore, is strongly related to the TC of the supply as well as its overall thermal design. By proper placement of critical components it is possible to greatly reduce or even eliminate the effect entirely. It is not uncommon for supplies of the 0.01 percent(regulation) variety to have drifts of between 0.05 to 0.15 percent for full line or full load variations. In fact, one manufacturer has suggested that anything better than 0.15 percent is good. Solutions to reducing thermal drift other than the obvious approach of improving the TC and reducing internal losses include a mechanical design that sets up a physical and thermal barrier between the critical amplifier components and heat dissipating elements. Exposure to outside surfaces with good ventilation is recommended. With care, 0.01 to 0.05 percent is obtainable.TRANSIENT RESPONSEMost power supplies of the type being discussed have a capacitor across the load terminals. This is used for stabilization purposes and usually determines the dominant time constant of the supply. The presence of this capacitor unfortunately leads to undesirable transient phenomena when the supply is used in the remote sensing mode①. Normally, transistorized power supplies respond in microseconds, but as the author has pointed out [6], the response can degenerate severely in remote sensing .The equivalent circuit is shown in Fig. 6. The leads from the power supply to the load introduce resistance r. Is is the sensing current of the supply and is relatively constant.Under equilibrium conditions,A sudden load change will produce the transient of Fig. 7. The initial "spike" is caused by an inductive surge Ldi/dt; the longer linear discharge following is the resultof the capacitor trying to discharge (or charge). The discharge time iswhereandThe limitations of I,, are usually not due to available drive of the final amplifier stages but to other limitations, current limiting being the most common. Units using pre regulators of the switching type (transistor or SCR types) should be looked at carefully if the characteristics mentioned represent a problem.①Remote sensing is the process by which the power supply senses voltage directly at the load.Fig. 6. Output equivalent circuit at remote sensing.Fig. 7. Transient response, remote sensing.Fig. 8. Block diagram.Preregulated supplies are used to reduce size and losses by monitoring and controlling the voltage across the class-A-type series passing stage (Fig. 8). Since the main regulator invariably responds much quicker than the preregulator, sufficient reserve should always be built into the drop across the passing stage. Failure to provide this may result in saturation of the passing stage when load is applied, resulting in a response time which is that of the preregulator itself.SWITCHING PREREGULATOR-TYPE UNITS The conventional class-A-type transistorized power supply becomes rather bulky, expensive, and crowded with passing stages, as the current and power level of the supply increases. The requirement of wide output adjustment range, coupled with the ability of the supply to be remotely programmable, aggravates the condition enormously. For these reasons the high-efficiency switching regulator has been employed as a preregulator in commercial as well as military supplies for many years. The overwhelming majority of the supplies used silicon controlled rectifiers as the control element. For systems operating from 60-cycle sources, this preregulator responds in 20 to 50 ms.Recent improvements in high-voltage, high-power switching transistors has made the switching transistor pproach more attractive. This system offers a somewhat lower-cost, lower-volume approach coupled with a submillisecond response time. This is brought about by a high switching rate that is normally independent of line frequency. The switching frequency may be fixed, a controlled variable or an independent self-generated (by the LC filter circuit) parameter [7], [8]. Faster response time is highly desirable since it reduces the amount of reserve voltage required across the passing stage or the amount of (storage) capacity required in the preregulator filter.A transistor suitable for operating as a power switch has a high-current, high-voltage rating coupled with low leakage current. Unfortunately, these characteristics are achieved by a sacrifice in thermal capacity, so that simultaneous conditions of voltage and current leading to high peak power could be disastrous. It therefore becomes mandatory to design for sufficient switch drive during peak load conditions and also incorporate current-limiting or rapid overload protection systems.Commercial wide-range power supplies invariably have output current limiting, but this does not limit the preregulator currents except during steady-state load conditions (including short circuits). Consider, for example, a power supply operating at short circuit and the short being removed suddenly. Referring to Fig. 8, the output would rise rapidly, reduce the passing stage voltage, and close the switching transistor. The resulting transient extends over many cycles (switching rate) so that the inductance of the preregulator filter becomes totally inadequate to limit current flow. Therefore, the current will rise until steady state is resumed, circuit resistance causes limiting, or insufficient drive causes the switch to come out of saturation. The latter condition leads to switch failure.Other operating conditions that would produce similar transients include output voltage programming and initial turn-on of the supply. Momentary interruption of input power should also be a prime consideration.One solution to the problem is to limit the rate of change of voltage that can appear across the passing stage to a value that the preregulator can follow. This can be done conveniently by the addition of sufficient output capacitance. This capacitance inconjunction with the current limiting characteristic would produce a maximum rate of change ofwhereC0 = output capacity.Assuming that the preregulator follows this change and has a filter capacitor Cl, then the switch current isDuring power on, the preregulator reference voltage rise must also be limited. Taking this into account,whereER = passing stage voltageTl = time constant of reference supply.The use of SCR's to replace the transistors would be a marked improvement due to higher surge current ratings, but turning them off requires large energy sources. While the gate turn-off SCR seems to offer a good compromise to the overall problem, the severe limitations in current ratings presently restrict their use.REFERENCES[1] J. G. Truxal, Control Engineer's Handbook. New York: McGrawHill, 1958, pp. 11-19.[2] Motorola Zener Diode/Rectifier Handbook, 2nd ed. 1961.[3] W. Steiger, "A transistor temperature analysis and its applica-tion to differential amplifiers," IRE Trans. on Instrumentation,vol. 1-8, pp. 82-91, December 1959.[4] L. P. Hunter, Handbook of Semi-Conductor Electronics. NewYork: McGraw Hill, 1956, p. 13-3.[5] "Standards publication for regulated electronic dc powersupplies," (unpublished draft) Electronic Power Supply Group,Semi-Conductor Power Converter Section, NEMA.[6] P. Muchnick, "Remote sensing of transistorized power sup-plies," Electronic Products, September 1962.[7] R. D. Loucks, "Considerations in the design of switching typeregulators," Solid State Design, April 1963.[8] D. Hancock and B. Kurger, "High efficiency regulated powersupply utilizing high speed switching," presented at the AIEEWinter General Meeting, New York, N. Y., January 27-February 1, 1963.[9] R. D. Middlebrook, Differential Amplifiers. New York: Wiley,1963.[10] Sorensen Controlled Power Catalog and Handbook. Sorensen,Unit of Raytheon Company, South Norwalk, Conn.With the rapid development of electronic technology, application field of electronic system is more and more extensive, electronic equipment, there are more and more people work with electronic equipment, life is increasingly close relationship. Any electronic equipment are inseparable from reliable power supply for power requirements, they more and more is also high. Electronic equipment miniaturized and low cost in the power of light and thin, small and efficient for development direction. The traditional transistors series adjustment manostat is continuous control linear manostat. This traditional manostat technology more mature, and there has been a large number of integrated linear manostat module, has the stable performance is good, output ripple voltage small, reliable operation, etc. But usually need are bulky and heavy industrial frequency transformer and bulk and weight are big filter.In the 1950s, NASA to miniaturization, light weight as the goal, for a rocket carrying the switch power development. In almost half a century of development process, switch power because of its small volume, light weight, high efficiency, wide range, voltage advantages in electric, control, computer, and many other areas of electronic equipment has been widely used. In the 1980s, a computer is made up of all of switch power supply, the first complete computer power generation. Throughout the 1990s, switching power supply in electronics, electrical equipment, home appliances areas to be widely, switch power technology into the rapid development. In addition, large scale integrated circuit technology, and the rapid development of switch power supply with a qualitative leap, raised high frequency power products of, miniaturization, modular tide.Power switch tube, PWM controller and high-frequency transformer is an indispensable part of the switch power supply. The traditional switch power supply is normally made by using high frequency power switch tube division and the pins, such as using PWM integrated controller UC3842 + MOSFET is domestic small power switch power supply, the design method of a more popularity.Since the 1970s, emerged in many function complete integrated control circuit, switch power supply circuit increasingly simplified, working frequency enhances unceasingly, improving efficiency, and for power miniaturization provides the broad prospect. Three end off-line pulse width modulation monolithic integrated circuit TOP (Three switch Line) will Terminal Off with power switch MOSFET PWM controller one package together, has become the mainstream of switch power IC development. Adopt TOP switch IC design switch power, can make the circuit simplified, volume further narrowing, cost also is decreased obviouslyMonolithic switching power supply has the monolithic integrated, the minimalist peripheral circuit, best performance index, no work frequency transformer can constitute a significant advantage switching power supply, etc. American PI (with) company in Power in the mid 1990s first launched the new high frequency switching Power supply chip, known as the "top switch Power", with low cost, simple circuit, higher efficiency. The first generation of products launched in 1994 represented TOP100/200 series, the second generation product is the TOPSwitch - debuted in 1997 Ⅱ. The above products once appeared showed strong vitality and he greatly simplifies thedesign of 150W following switching power supply and the development of new products for the new job, also, high efficiency and low cost switch power supply promotion and popularization created good condition, which can be widely used in instrumentation, notebook computers, mobile phones, TV, VCD and DVD, perturbation VCR, mobile phone battery chargers, power amplifier and other fields, and form various miniaturization, density, on price can compete with the linear manostat AC/DC power transformation module.Switching power supply to integrated direction of future development will be the main trend, power density will more and more big, to process requirements will increasingly high. In semiconductor devices and magnetic materials, no new breakthrough technology progress before major might find it hard to achieve, technology innovation will focus on how to improve the efficiency and focus on reducing weight. Therefore, craft level will be in the position of power supply manufacturing higher in. In addition, the application of digital control IC is the future direction of the development of a switch power. This trust in DSP for speed and anti-interference technology unceasing enhancement. As for advanced control method, now the individual feels haven't seen practicability of the method appears particularly strong,perhaps with the popularity of digital control, and there are some new control theory into switching power supply.（1）The technology: with high frequency switching frequencies increase, switch converter volume also decrease, power density has also been boosted, dynamic response improved. Small power DC - DC converter switch frequency will rise to MHz. But as the switch frequency unceasing enhancement, switch components and passive components loss increases, high-frequency parasitic parameters and high-frequency EMI and so on the new issues will also be caused.（2）Soft switching technologies: in order to improve the efficiency ofnon-linearity of various soft switch, commutation technical application and hygiene, representative of soft switch technology is passive and active soft switch technology, mainly including zero voltage switch/zero current switch (ZVS/ZCS) resonance, quasi resonant, zero voltage/zero current pulse width modulation technology (ZVS/ZCS - PWM) and zero voltage transition/zero current transition pulse width modulation (PWM) ZVT/ZCT - technical, etc. By means of soft switch technology can effectively reduce switch loss and switch stress, help converter transformation efficiency （3）Power factor correction technology (IC simplifies PFC). At present mainly divided into IC simplifies PFC technology passive and active IC simplifies PFC technology using IC simplifies PFC technology two kinds big, IC simplifies PFC technology can improve AC - DC change device input power factor, reduce the harmonic pollution of power grid.（4）Modular technology. Modular technology can meet the needs of the distributed power system, enhance the system reliability.（5）Low output voltage technology. With the continuous development of semiconductor manufacturing technology, microprocessor and portable electronic devices work more and more low, this requires future DC - DC converter can provide low output voltage to adapt microprocessor and power supply requirement of portable electronic devicesPeople in switching power supply technical fields are edge developing related power electronics device, the side of frequency conversion technology, development of switch between mutual promotion push switch power supply with more than two year growth toward light, digital small, thin, low noise and high reliability, anti-interference direction. Switching powersupply can be divided into the AC/DC and DC/DC two kinds big, also have AC/AC DC/AC as inverter DC/DC converter is now realize modular, and design technology and production process at home and abroad, are mature and standardization, and has approved by users, but the AC/DC modular, because of its own characteristics in the process of making modular, meet more complex technology and craft manufacture problems. The following two types of switch power supply respectively on the structure and properties of this.Switching power supply is the development direction of high frequency, high reliability, low consumption, low noise, anti-jamming and modular. Because light switch power, small, thin key techniques are changed, so high overseas each big switch power supply manufacturer are devoted to the development of new high intelligent synchronous rectifier, especially the improvement of secondary devices of the device, and power loss of Zn ferrite (Mn) material? By increasing scientific and technological innovation, to enhance in high frequency and larger magnetic flux density (Bs) can get high magnetic under the miniaturization of, and capacitor is a key technology. SMT technology application makes switching power supply has made considerable progress, both sides in the circuitboard to ensure that decorate components of switch power supply light, small, thin. The high frequency switching power supply of the traditional PWM must innovate switch technology, to realize the ZCS ZVS, soft switch technology has becomethe mainstream of switch power supply technical, and greatly improve the efficiency of switch power. For high reliability index, America's switch power producers, reduce by lowering operating current measures such as junction temperature of the device, in order to reduce stress the reliability of products made greatly increased.Modularity is of the general development of switch power supply trend can be modular power component distributed power system, can be designed to N + 1 redundant system, and realize the capacity expansion parallel. According to switch power running large noise this one defect, if separate the pursuit of high frequency noise will increase its with the partial resonance, and transform circuit technology, high frequency can be realized in theory and can reduce the noise, but part of the practical application of resonant conversion technology still have a technical problem, so in this area still need to carry out a lot of work, in order to make the technology to practional utilization.Power electronic technology unceasing innovation, switch power supply industry has broad prospects for development. To speed up the development of switch power industry in China, we must walk speed of technological innovation road, combination with Chinese characteristics in the joint development path, for I the high-speed development of national economy to make the contribution. The basic principle and component functionAccording to the control principle of switch power to classification, we have the following 3 kinds of work mode:1) pulse width adjustment type, abbreviation Modulation PulseWidth pulse width Modulation (PWM) type, abbreviation for. Its main characteristic is fixed switching frequency, pulse width to adjust by changing voltage 390v, realize the purpose. Its core is the pulse width modulator. Switch cycle for designing filter circuit fixed provided convenience. However, its shortcomings is influenced by the power switch conduction time limit minimum of output voltage cannot be wide range regulation; In addition, the output will take dummy loads commonly (also called pre load), in order to prevent the drag elevated when output voltage. At present, most of the integrated switch power adopt PWM way.2) pulse frequency Modulation mode pulse frequency Modulation (, referred to PulseFrequency Modulation, abbreviation for PFM) type. Its characteristic is will pulse width fixed by changing switch frequency to adjust voltage 390v, realize the purpose. Its core is the pulse frequency modulator. Circuit design to use fixed pulse-width generator to replace the pulse width omdulatros and use sawtooth wave generator voltage? Frequency converter (for example VCO changes frequency VCO). It on voltage stability principle is: when the output voltage Uo rises, the output signal controller pulse width unchanged and cycle longer, make Uo 390v decreases, and reduction. PFM type of switch power supply output voltage range is very wide, output terminal don't meet dummy loads. PWM way and way of PFM respectively modulating waveform is shown in figure 1 (a), (b) shows, tp says pulse width (namely power switch tube conduction time tON), T represent cycle. It can be easy to see the difference between the two. But they have something in common: (1) all use time ratio control (TRC) on voltage stability principle, whether change tp, finally adjustment or T is。
毕业设计中英文翻译
本科生毕业设计（论文）外文翻译毕业设计（论文）题目：电力系统检测与计算外文题目：The development of the single chipmicrocomputer译文题目：单片机技术的发展与应用学生姓名： XXX专业： XXX指导教师姓名： XXX评阅日期：单片机技术的发展与应用从无线电世界到单片机世界现代计算机技术的产业革命，将世界经济从资本经济带入到知识经济时代。
在电子世界领域，从 20 世纪中的无线电时代也进入到 21 世纪以计算机技术为中心的智能化现代电子系统时代。
现代电子系统的基本核心是嵌入式计算机系统(简称嵌入式系统)，而单片机是最典型、最广泛、最普及的嵌入式系统。
一、无线电世界造就了几代英才。
在 20 世纪五六十年代，最具代表的先进的电子技术就是无线电技术，包括无线电广播，收音，无线通信(电报)，业余无线电台，无线电定位，导航等遥测、遥控、遥信技术。
早期就是这些电子技术带领着许多青少年步入了奇妙的电子世界，无线电技术展示了当时科技生活美妙的前景。
电子科学开始形成了一门新兴学科。
无线电电子学，无线通信开始了电子世界的历程。
无线电技术不仅成为了当时先进科学技术的代表，而且从普及到专业的科学领域，吸引了广大青少年，并使他们从中找到了无穷的乐趣。
从床头的矿石收音机到超外差收音机；从无线电发报到业余无线电台；从电话，电铃到无线电操纵模型。
无线电技术成为当时青少年科普、科技教育最普及，最广泛的内容。
至今，许多老一辈的工程师、专家、教授当年都是无线电爱好者。
无线电技术的无穷乐趣，无线电技术的全面训练，从电子学基本原理，电子元器件基础到无线电遥控、遥测、遥信电子系统制作，培养出了几代科技英才。
二、从无线电时代到电子技术普及时代。
早期的无线电技术推动了电子技术的发展，其中最主要的是真空管电子技术向半导体电子技术的发展。
半导体电子技术使有源器件实现了微小型化和低成本，使无线电技术有了更大普及和创新，并大大地开阔了许多非无线电的控制领域。
网页设计专业毕业设计外文翻译
Produce the design of the tool and realize automaticallyon the basis of JSP webpageIt is an important respect that Internet uses that Web develops technology, and JSP is the most advanced technology that Web is developed , it is present Web developer's first-selected technology. But because JSP has relatively high expectations for Web developer, a lot of general Web developers can not use this advanced technology . The discussion produces the design of the tool and realizes automatically on the basis of JSP webpage of the template and label storehouse, put forward concrete design philosophy and implementation method .With the popularization of WWW (World Wide Web ), the technology of the dynamic webpage is developed rapidly too. From original CGI (Common Gateway In-terface ) to ASP (Active Server Page ), have met the webpage developer to the demand for developing technology of the dynamic webpage to a certain extent. But no matter CGI or ASP have certain limitation, for instance, consuming to resources of the server of CGI, ASP can only be used etc. with Microsoft IIS, all these have limited scope of application of the technology, have hindered their popularization greatly. The vast page developers all look forward to a kind of unified page and develop technology earnestly, characteristic that this technology there should be：①Have nothing to do with the operating platform, can run on any Web or the application program server ;②Show the logic and page of application program that separates ; ③Offer codes to put in an position, simplify and develop the course based on interactive application program of Web.JSP (Java Server Page ) technology is designed and used for responding to the request that like this. JSP is developed technology by the new webpage that Sun MicroSystem Company put out in June of 1999, it is that Web based on Java Serv-let and the whole Java system develops technology, and Servlet2. Expansion of 1API. Utilize this technology, can set up advancedly , safely and stepping dynamic websites of the platform .Java is the future mainstream to develop technology , have a lot of advantages . JSP is Java important application technology on Internet/Intranet Web , get extensive support and admit, it can conbine with various kinds of Java technology together intactly , thus realize very complicated application.As a kind of technology of development based on text , taking showing as centre, JSP has offered all advantages of Java Servlet. Logic function in order to make sure and showing the function was separated , JSP can already work with JavaBeans , Enterprise JavaBeans (EJB ) and Servlet . The developer of JSP can finish the work that majority and website's logic are correlated with through using JavaBeans , EJB and Servlet , and only assign the work shown to JSP page to finish. Content and show advantage that logic separate lie in , upgrade person , page of appearanceneedn't understand Java code , the personnel upgrading Javas needn't be experts who design webpage either. This can define Web template in JSP page with Javas , in order to set up websites made up of a page with similar appearance. Java completion data offer, have Java code among template, this mean template these can write by one HTML person is it maintain to come.JSP develops technology as the webpage of the mainstream at present, has the following characteristics：(1) Separate the formulation and showing of the content : Using JSP technology, the page developer of Web can use HTML or XML identification to design and format the final page . Use JSP identification or bound foot turn into dynamic content of page actually (whether content according to is it come change to ask). Produce logic of content of the identification and JavaBeans package , truss up of the little script encapsulation, all scripts run in the end of the server. If key logic among identification and JavaBeans, then other people, such as Web administrative staff and page designer encapsulation, can edit and use JSP page , and does not influence the formulation of the content .(2) Emphasize the reusable package : Most JSP pages depend on the reusable one, the package stepping the platform finish more complicated treatment with required application program. Benefitting from the independence of operating platform of Java, the developer can be very convenient to share and exchange and carry out the ordinary package that operated, or make these packages used by more users. The method based on package has accelerated the total development course, the efficiency of improving the project and developing wholly greatly.Though JSP is powerful, it requires the webpage developer should be quite familiar with Java. There are still relatively few Java programmers now, for general webpage developer, the grammar of JSP is more difficult to grasp . So, need a kind of webpage developing instrument and offer commonly used JSP application to general webpage developer, is it understand general page develop developer of technology (HTML ) can use strong function of JSP too only to let.Systematic design object and main technology of use：(1)Design objectSystem this design object for understand but HTML understand general webpage developer of JSP offer a webpage developing instrument at all only, enable them to follow the systematic file, use the daily function of JSP through the label, produce one finally and only include static HTML and dynamic JSP webpage of JSP label.(2)Main technologyThis system is in the design, consider using the technology of the template and JSP label to realize mainly.1、Technology of the templateThe technology of the template is widely applied to various kinds of development and application system. It produces some commonly used frame structure in advance , uses the family to choose the template from the template storehouse conveniently according to the needs of one's own one, is it is it put up to go again by oneself to need , save construction period in user , facilitate use of user. In this system , classify the page according to the function type , sum up the commonly used page type, produce the template storehouse.2、Storehouse technology of the labelIn JSP, movements can create and visit the language target of the procedure and influence the element exported and flowed. JSP has defined six standard movements. Except six standard movement these, user can define own movement finish the specific function. These movements are known as the customer movement, they are the reusable procedure module . Through movement these, programmer can some encapsulation stand up too display function of page in JSP page, make the whole page more succinct and easier to maintain. In a JSP page, movements were transfered through the customer label in these customers. And the label storehouse (Tag Library ) is the set of the customer label.JSP label storehouse is that one kind produces the method based on script of XML through JavaBeans. It is one of the greatest characteristics of JSP. Through the label storehouse , can expand JSP application unrestrictedly , finish any complicated application demand.JSP label storehouse has the following characteristic：①Easy to use: The labels in JSP and general HTML marks are totally the same in appearance, it is as convenient as ordinary HTML mark to use.②The easy code is paid most attention to: Every label in the label storehouse can finish certain function . Define ready to eat one label storehouse , is it pack one Jar file the label storehouse to need only, then only need use this label storehouse in other systems afterwards, needn't develop codes again , has raised the system and developed efficiency greatly, have reduced the development cost.③The easy code is safeguarded: All application logic is encapsulated in label processor and JavaBeans, all labels concentrate on a label storehouse. If need to upgrade codes or need to revise the function on a webpage, only need to revise the corresponding label. Maintain way in unison through this kind , it is unnecessary in each webpage is it is it fix to act as to get onning, have reduce the work load safeguarded greatly, has economized the cost of safeguarding.④The easy system is expanded : If need to add the new function to the system , only need to define a new label to finish this function, do not need to do any change to other respects of thesystem. Can inherit JSP normal characteristics of various fields in the label storehouse. Can expand and increase the function of JSP unrestrictedly like this, and does not need to wait for the appearance of the next edition JSP .Systematic composition and realizing：(1)The system making upThis system is made up of four parts mainly：1、The database joins some: This system supports several daily databases , including Oracle, Sybase, MSSQLServer, MySQL and DB2, use JDBC and database to link to each other according to database type and database name , user name , password that users offer that users choose.2、The basic form of system produces some: After joining with the database , produce the basic form TC-Tables and TC-Columns of two systems according to the user name linking to each other with the database , TC-Tables form includes English name , Chinese name and some attribute of form belonging to this user in this database , for instance can revise , can inquire about ; The Chinese and English name of the row and some other attribute that TC-Columns form includes belonging to all forms of this user's in this database . For instance can show , can inquire about . Basic information of the database that these basic forms of two systems provide to user's institute for use in the course of development of the whole system.3、The template is chosen to produce some with the webpage: This part is a key part of a system. It includes two pieces of sub module .①The template is chosen some: The system offers the template to user and chooses the interface, let users choose the templates used from the template storehouse according to the need.②The template is dealt with some: According to template that user choose, system transfer designated template deal with module is it punish to go on to these template. When dealing with the label that the procedure meets in the template, offer the mutual interface to user, let user input parameter for designated label , prove system validity of label that user input. Finished the formulation of JSP page systematically finally.Webpage preview is with revising some: After the webpage was produced out, the system has offered a webpage preview window and code to user and looked over that revises the window. Through this preview window, users can look at the result of JSP page produced out in advance . If user static result of respect in page very satisfied, user can through code look over revise window revise HTML code of code. If users have further demands for the static result of the page, the system has also offered a piece of interface which transfers DreamWeaver editing machine to user, users can use it to carry on further modification and perfection to the static result of JSP page that is produced out .(2)Systematic realization1、Realization of the template storehouse and label storehouseThe planning and design of the label storehouse are essential in the whole system design, efficiency that the degree and system that are put in an position have operated that its relation has reached codes. Its planning should follow the following principle .(1) Should try one's best little including static HTML among label. To general user, the label is transparent. Users can not look over and revise labels . If include too many static HT-ML sentence in the label , will influence the modification and perfection of user's static result to the page, limit the use of the label.(2) Try one's best to raise the paying most attention to degree of the code. Is it is it is it is it is it is it get to JSP public JSP out to withdraw to use to try one's best to classify to go on to use, form labels. Do not use and realize this application repeatedly in each label . While revising and perfecting to using like this , only need to revise this label, maintenance of the easy code.(3) Facilitate users' use. While designing the label storehouse , should fully consider users' operating position , it can very easy and understanding and using labels conveniently to use the family.①Definition of the label storehouse: Define a label storehouse, must define a label storehouse and describe the file (TLD ) at first . This is a file of script based on XML, have defined the edition of XML in this file , codes used, the edition , name and definition and parameter of all labels included in this storehouse of the label storehouse of the edition of the label storehouse , JSP used describe, including the name of the label, corresponding Javas of label, description information of the label ,etc..②Realization of the label: One label first special Java type, this each must inherit TagSupports , this each is in javax. servlet. jsp. Define in tagext bag . In the labels, the parameter which includes this label initializes the subject treatment method (Handler ) of method (Set/Get ) , label and method available for making the first class label to adjust,etc..③Realization of the template : A template is that one contains JSP file that labels quoted . In order to quote the labels defined in the template , must introduce the label storehouse at first .＜％＠taglib uri＝“tag．tld”prefix＝“ctag”％＞Among them uri appoints the label storehouse to describe the route of the file ; Prefixes used when prefix appoints to quote labels.While quoting the designated label in the template , use the designated prefix while introducing the label storehouse, appoint the name of the label; It is the parameter assignment of the label.2、Systematic development environmentWhat this systematic subject procedure making is used is JBuilder 6 of Borland Company. 0, it is Front-Page2000 of Microsoft Company that the template is developed and used, what the label storehouse is developed and used is UltraEdit editing machine, what JDK is adopted is JDK1.4. The system testing environment is JRun3. 0.Java future mainstream to develop language, and Java using JSP will become major technology that Web will be developed in the future too mainly at Web. This system has adopted the label storehouse , one of the biggest characteristics of JSP, enable the general Web developer to use JSP strong dynamic page function conveniently too, develop JSP dynamic Web page of the modern techniques. Because this system adopts Java to develop, can run under the operating system of any support graphic interface , have realized complete having nothing to do with the platform. This system is easy to expand and perfect. Can consider offering the interface to user afterwards , will use the family to expand the template storehouse and label storehouse by oneself, strengthen the systematic function further.List of references：[1] Cay S. Horstmann,Gary Cornell. Java 2 key technology (CoreJava 2 ) [M ]. Beijing: Publishing house of the mechanical industry.[2] Bruce Eckel. Java programming thought (Thinking in Java ) [M ]. Beijing: Publishing house of the mechanical industry.[3] Joseph L. Weber. Java 2 programming is explained in detail (Using Java 2) [M ]. Beijing: Electronic Industry Press.[4] Borland Company. Building Applications with JBuilder.基于JSP网页自动生成工具的设计与实现Web开发技术是Internet应用的一个重要方面，而JSP又是Web开发的最先进的技术，是当前Web开发人员的首选技术。
毕业设计英文翻译解读
金刚钻的工业化运用一个程序一般需要50至70美网。
在这样的切割频率下，工具的负载量是比较低的。
而欧洲这样的程序下金刚钻的模型是完全不一样的！在我国，在这样的程序下，普遍金刚钻工具在非常自由的切割条件下，产品是不规则的易碎的微粒！在欧洲因为各种因素，情况是不同的。
因为欧洲的生活水平远高于我国，因此，他们的劳动力成本也要高。
为了使欧洲最大的石材生产商保持竞争力，他们必须要把注意力从原材料转移到生产的有效输出和最大化输出。
这就要求产品从原材料到成品的生产过程中尽可能减小能源的耗费和不必要的浪费。
该方法需要机床技术能够高速运作和先进的加工，可进行可靠的长时间持续的，无人值守操作。
在20世纪90年代，在机械和金刚石工具技术方面有很大的发展，使产量增加和降低生产成本。
如果我们对比一下欧洲和中国生产标准，我们可以看到在机器和工具的生产方面，中欧存在很大的差距。
在欧洲，制造这些瓷砖几乎是完全自动的，因为高效率的机械设计和自动处理设施。
最新一代的锯床这种应用能够使用主轴高达80分直径锯片。
机器和工具的设计，在达到下列的参数下，切割率是可以更快的。
•表面速度：- 25 – 35m / s•切削深度：-1mm•大桥速度：- 17m/min•切割速度：- IPOcm/5min或1m/h每个刀片•机输出：- 640m/5day（8小时每天）在这样的条件下，生产浪费减至最低，产量确更高。
通常情况下，在欧洲，刀片会产生10mm的缺口，而中国有12mm。
并且相对于中国12-15mm的切面的切口，欧洲只有10-12mm的切口。
在实现生产最大化材料处理和优化加工时间也是关键，厚片的切据被自动转移到自动的二次加工。
在这样精确的切割率下，对于金刚钻工具的要求是很高的，在程序控制下，型号和尺寸与中国的标准下是有很大不同的。
由于切割率相对高很多，最通常的尺寸是30-50。
切割率高，意味着工具的负载量也高，金刚钻的性质也会不一样！金刚钻的要求一般都是统一的，强大，块状颗粒，这是使在长时间的高负荷下，保持高产量。
本科毕业设计外文文献翻译
（Sheaｒ waｌl ｓt ｒuctural desigｎ ofh ｉgh-ｌev ｅl fr ａmeworkＷｕ Jiche ｎgＡbstract ： In t ｈis pape ｒ the basic c ｏｎcepts of ｍａn ｐow ｅr ｆｒom th ｅ ｆra ｍｅ sh ｅａr w ａｌl str ｕc ｔｕｒｅ, analy ｓis of the ｓtruct ｕr ａｌ des ｉgn ｏf th ｅ c ｏnt ｅnt ｏｆ t ｈe fr ａme she ａr wall, in ｃｌudi ｎg the ｓeism ｉc wa ｌl she ａr spa本科毕业设计外文文献翻译学校代码： 10128学 号：题 目：Shear wall structural design of high-level framework 学生姓名： 学 院：土木工程学院 系 别：建筑工程系 专 业：土木工程专业（建筑工程方向） 班 级：土木08-（5）班 指导教师： (副教授)ｎratiｏdesign, ａnd a concrｅtｅｓtruｃtuｒe in thｅmｏst co ｍmonｌy useｄframe shear walｌstｒｕcturｅtｈｅdesign of p ｏiｎｔs to note.Keyworｄs: cｏncrｅｔｅ; fｒaｍｅshｅａｒwall sｔｒucｔｕre；hiｇh－risｅbuildｉｎｇsThe wall is aｍoｄern high－rｉｓe buiｌdiｎgs is an iｍpo ｒｔant buiｌdinｇconｔｅnt, the ｓize of thｅfraｍe sheａr wall must comｐly with buildｉng reguｌａtｉons. The pｒｉnｃipｌe is ｔhat the largeｒsｉzｅbｕt the thｉｃknessｍuｓt ｂｅsmaller gｅoｍetric featｕrｅｓshoｕlｄｂe ｐｒeｓented ｔo the pｌatｅ,ｔｈe forｃe is close to cylｉndrｉcal.Ｔhe waｌl sｈｅar wa ｌl strｕｃｔure ｉs a flaｔcomｐonent. Itｓeｘposure to tｈe force aｌoｎg ｔhe ｐlane leｖｅl of theｒole ofｓｈear and momｅｎt, must also take ｉｎtｏａccounｔthe veｒｔical preｓsure.Opeｒate unｄer thｅcomｂiｎed actｉｏn oｆbenｄing momeｎts and axial force aｎｄsheａr forcｅbｙthe caｎtilｅｖｅr deep beａm uｎder ｔｈe acｔion of the force leveｌｔo lｏo ｋinto ｔｈe bottom mouｎted on ｔhe basｉs of. Sheaｒｗaｌl ｉｓdiｖidｅｄinｔo a whole walｌand ｔheａssoｃiated ｓｈeａr wall in thｅactual project,a wholｅwａlｌfor ｅxａmpl ｅ, suｃh as ｇenｅraｌhｏusiｎｇｃonstｒuction in tｈe gablｅｏr fish bｏne strｕcture ｆｉlｍwａｌls ａnd small opｅningｓwall.Cｏupled Sｈeａr ｗalls are ｃonnｅcted bｙｔhｅcｏupｌing ｂeam shｅａr wall.Buｔｂecause tｈeｇｅnerａlｃｏupling beaｍstｉｆfness is less thaｎｔhe wall stiｆfnｅsｓof the lｉmbs，ｓｏ. Wａlｌliｍb aｌonｅis obviｏus.The ｃｅntral beam of tｈeｉnflｅｃtion pｏｉnｔtｏpay aｔtenｔiｏｎto tｈeｗaｌl pressｕre thａn the limiｔs of the lｉmb axis. Will forｍa shortｗiｄe beａms，widｅcolｕmn wａll liｍｂｓhear wａll ｏpｅnings toｏlarge ｃomｐonｅnt aｔbothｅn ｄs ｗith jｕst the domain of vａｒiabｌe crosｓ－ｓecｔｉon ro ｄin ｔhe intｅrｎａｌforcｅｓｕnder tｈｅaｃtioｎof maｎy Ｗalｌlｉmb iｎflｅcｔion point Ｔhｅｒeｆoｒe, ｔhe cａｌcula ｔions ａｎd consｔruction sｈouldAccordinｇtｏappｒoxiｍａｔe tｈe framｅstｒucｔure to ｃonsideｒ.Tｈe desｉｇｎof ｓhｅａr walls ｓhoulｄbe based on the cｈａractｅrisｔics ｏf ａvａｒｉｅty oｆwall itseｌｆ,ａnd dｉfferｅnｔmeｃhanical ch ａrａcteｒisｔｉcｓand requireｍents,wall oｆthｅinternａｌforceｄistrｉbutｉon and failurｅmoｄｅs ｏf sｐecific and cｏmprehensive ｃonｓideration of the design rｅinｆorcemｅnt aｎd stｒuctural measｕres. Ｆrame sｈear wall ｓｔrｕctuｒe deｓiｇn is to cｏｎsider the ｓtructｕre of the oｖerall ａnａｌysis for ｂoｔh dｉrecｔｉｏｎsｏｆthｅhｏrｉzontal and vｅrtiｃalｅfｆects. Oｂtain thｅinternal force ｉs reｑuirｅd in ａccｏrdancｅｗｉｔｈtｈe bias or paｒtｉal ｐull normal sｅcｔｉon forｃｅｃaｌculatiｏn.The waｌl strｕcture oｆtheｆｒame sｈear ｗall ｓｔructural dｅsign of ｔhe coｎtent frame hｉgh-rise buildings, in ｔhe actual ｐrｏjeｃｔiｎｔhｅuse of thｅｍoｓt seisｍic ｗａlls have suffiｃient quantitｉeｓto meｅt ｔheｌｉmitsｏf the lａyer displacement, the loｃation iｓｒelａtiｖely flexiblｅ. Seiｓmic wａll for cｏntinuous layout，ｆulｌ-length ｔhroｕgh．Should bｅdesigned to avoid the waｌl mutaｔioｎs ｉn limb ｌｅｎgth and alignment is noｔuｐａnd down the ｈolｅ. The samｅtｉme．Tｈe inｓide of ｔhe hole marginｓcｏlｕｍｎshｏｕld not ｂｅｌｅssｔhan３00mm ｉｎordｅｒtｏguaraｎteｅtheｌengtｈof the colｕｍn ａs the edgｅof tｈe coｍponent and constｒａiｎt eｄgｅcｏｍponeｎts．Thｅbi-direc ｔiｏnal laｔerａl forｃe ｒesiｓting strucｔurａl fｏrm of verticａl aｎｄhorｉzontaｌwalｌcoｎnected.Eａｃh ｏｔhｅr as ｔhe ａffiｎiｔｙof the shｅar wall. Ｆor ｏnｅ, two seismic frａme sｈe ａr ｗalｌｓ,ｅｖen beam highｒatio ｓhould noｔgreateｒthan 5 aｎd a height of nｏt less thaｎ400mm.Midline colｕmnａnd beａmｓ,wall ｍｉdline shouｌdｎoｔbe greaｔer tha ｎthe ｃoｌｕmｎwidｔｈof1/4，ｉn ordｅr ｔｏreｄuce thｅtoｒsional eｆfect of the sｅiｓmｉｃacｔion ｏnｔｈｅｃolｕmn．Oｔhｅrwｉsｅcan be taken tｏstrengthｅn theｓtirruprａｔｉo iｎｔhe cｏlｕmn tｏmake ｕp.If thｅshear wａｌl sheａｒsｐａn ｔhａnｔhe ｂig twｏ. Ｅveｎthe beａｍcro ｓs-heｉｇht ratiｏgreateｒthan 2.5, ｔhen tｈe design presｓｕｒe ｏf thｅｃｕt shoulｄnoｔmａkｅａｂig 0.2. Howevｅｒ, ｉf the sheａｒwallｓheａr sｐａｎｒatiｏof ｌess than two couｐlinｇｂeａms sｐan of ｌeｓs than ２．5, then the shear coｍｐres ｓiｏn rａｔiｏis noｔgreaｔer thａn 0.15. Thｅｏther haｎｄ，ｔhe bｏttom oｆthe fraｍe ｓhｅar walｌstructure ｔo enhａnce tｈｅdｅsign sｈould ｎoｔbe leｓs thaｎ２０0mmａnd noｔlesｓthaｎstorey 1/１6，othｅｒｐaｒtｓｓhｏulｄnot be lｅss than 160mm ａnd ｎｏt ｌｅss thaｎｓtoｒey １/20. Arounｄthe wall of the frame ｓhｅar ｗall strucｔure sｈｏulｄbe set ｔo the beａm or dark bｅamａnd the sｉｄe columｎｔｏform a borｄｅr. Ｈoｒizｏntａl ｄｉｓtrｉbuｔioｎoｆsｈear waｌls cａn from the sheａr effect，tｈｉs design wｈen ｂuilｄｉng higｈｅr longeｒor fｒaｍｅｓtructｕre reinfoｒcｅment shｏuld be aｐprｏpｒiatelｙincｒeａｓed, ｅspｅcｉａlｌy in the sｅnｓitivｅｐarts of the beam pｏsition ｏr teｍperaｔuｒe, stiffnｅsｓchａnge is besｔappｒopriatｅly increased, ｔｈeｎcｏnsidｅration sｈoulｄbe ｇｉveｎｔo the wａlｌvertｉcaｌreiｎforｃemeｎt,becaｕse ｉt is mａinly fｒom the bｅnding efｆecｔ, aｎｄtake in ｓome ｍｕlti-ｓtorｅｙshｅａｒｗａll structuｒereinforcｅｄreｉnｆorceｍent rate -likｅlｅsｓconｓtｒained edgｅｏｆｔhｅcomｐonent or components reinforｃemeｎt of thｅedge ｃomｐｏnent.Referｅnces: [1 sad Hａyaｓhi,He Yaming. Ｏn the shorｔshｅar ｗall ｈigh-riｓe bｕilｄinｇｄesign ［J]．Kｅｙｕaｎ, 2008, (O2).高层框架剪力墙结构设计吴继成摘要: 本文从框架剪力墙结构设计的基本概念人手, 分析了框架剪力墙的构造设计内容, 包括抗震墙、剪跨比等的设计, 并出混凝土结构中最常用的框架剪力墙结构设计的注意要点。
毕业设计英文翻译
1
Introduction
The increasing eating, ventilating and airconditioning (HVAC) systems has initiated a great deal of research aiming at energy savings. With the consolidation of the demand for human comfort, HVAC systems have become an unavoidable asset, accounting for almost 50% energy consumed in building and around 10-20% of total energy consumption in developed countries (Perez-Lombard et al. 2008) Because building cooling load varies with the time of the day, an HVAC system must be complemented with an optimum design scheme to reduce the energy consumption by keeping the process variables to their required setpoint efficiently in order to maintain comfort under any load conditions. One of the effective ways of achieving energy efficiency is to design cooling coil configurations properly that has motivated us to propose a design procedure which significantly lead to an overall reduction in HVAC energy consumption. Therefore, it is not surprising
毕业设计英语翻译
毕业设计英语翻译【篇一：毕业设计中英文翻译】英文资料翻译题目基于网络信息的自动化控制系别专业班级学生姓名学号指导教师2012年4月con trol based on n etwork andin formatio na automation networking application areas networking is used in all areas of automation. in factory automation, process automati on and buildi ng automati on n etworks perform diverse tasks. likewise, there are dist inct differe nces betwee n tasks performed for applicati ons in differe nt in dustry sectors that all have unique characteristics and con seque ntly vary ing requireme nts. the way devices are conn ected, con figured, and excha nge data also differ.there is no on e-size-fits-all for in dustrial n etworks; rather, buses are optimized foter differe nt characteristics. for example, factory automati on and process automati on are ofte n used in harsh and hazardous en viro nments where a producti on in terrupti on is costly. these requireme nts con trast sig nifica ntly with build ing automati on, for example, where keep ing costs low is a main driving force.factory automatio nfactories with assembly-l ine manu facturi ng, as in the automotive, bottli ng, and mach inery in dustries, are predo minan tly con trolled using discrete logic and sen sors that sense whether or not, for example, a process mach ine has a box standing in front of it. the network types ideal for simple discrete i/o focus on low overhead and small data packets, but they are un suitable for larger, messages like con figurati on download and the like. examples of this network type are seriplex, i nterbus-s, and as-i (as-in terface), which are sometimes called sen sor buses or bit level buses. other more adva need protocols orie nted toward discrete logic in clude device net, con troln et, and profibus (dp and fms applicati on profiles). these buses are sometimes referred to as devicebuses or byte-level buses. factory automati on in volves fast-moving mach inery and therefore requires quicker resp onse than slower processes. traditi on ally, these tasks have bee n han dled by plcs.process automati onprocess plants in industry segments like refining, pulp paper, power, and chemicals are dominated by continuous regulatory con trol. measureme nt is an alog (here meaning scalar values tran smitted digitally), and actuatio n is modulat ing. of course, process industries also use some discrete control and the predo minan tly discrete manu facturi ng in dustries use some modulating. fieldbus on/off valves are already available in the market, as are small remotely moun ted i/o modules for discrete sen sors .in the past, a dcs or sin gle-loop con troller did this.process-related n etwork in clude foun dati on fieldbus, profibus (pa application profile), and hart. all these buses as a category are now typically referred to as fieldbus (without the capital f), though some would argue that one or the other does not bel ong. these three protocols were specifically desig ned for bus-powered field in strume nts with predefi ned parameters and comma nds for asset man ageme nt in formatio n like iden tificati on, diag no stics, materials of con structi on, and fun cti ons for calibratio n and commissi onin g. i n term of size, the n etworks used in in dustrial automati on are con sidered to con stitute local area n etworks (la n) spa nning areas no greater tha n a kilometer or two in diameter and typically confined to a sin gle build ing or a group of build in gs. n etworks that exte nd only a few meters are in sufficie nt, and n etworks that spa n cities or eve n the globe are overkill.field and host tier networkseven within control systems for the process sector there is a n eed for differe nt n etwork characteristics at each tier of the control system hierarchy. at the field and there are instruments such as tran smitters and valve positti oners that have their specific needs, and valve positioners that have their specific n eeds (fig.5-1a-1). whe n fieldbus bega n to evolve, the process in dustry put a large nu mber of requireme nts on the field-level n etwork that were not met by other types of n etworks. many new desig n con sideratio ns n eeded to be take n into acco unt.on the upper tier, data from all the field-level networks have to be marshaled on to a si ngle host-leveln etwork that also serves any tasks the pla nt may have that seem related to factory automatio n.fig.5-1a-1 field level at the field level, the dominant protocols for process instrument are hart, foundation fieldbus h1, and profibus pa.hart is significantly different from the other two in that it is a so-called smart protocol, that is a comb in atio n of digital com muni cati on simulta neously superimposed on a conven tio nal 4-20ma sig nal. as such, the hart protocol has bee n an ideal in termediate solutio n in the tran siti on from an alog. hart is compatible with exist ing an alog recorders, controllers, and indicators while at the same time it makes possible remote configuration and diagnostics using digital com mun icatio n. the hart protocol does allow several devices to be multidropped on a sin gle pair of wires, but this is a capability in freque ntly explored because of the low update speed, typically half a sec ond per device. for a vast majority of in stallati ons hart devices are conn ected point to point, that is, one pair of wires for each device and a han dheld conn ected temporarily from time to time for configuration and maintenance. both foundation fieldbus h1 and profibus pa are completely digital and even use identical wiri ng, follow the iec 61158-2 sta ndard. however, bey ond that there are major differe nces betwee n these two protocols, and depe nding on the desired system architecture one may be more suitable than the other.at the field level, i nstrume nts appear in large qua ntities, ofte n in the hundreds or thousands. the wire run are very long, as the network cable must run from the control room all the way into the field, up towers, and the n branching out to devices scattered throughout the site. because there is a limit to the nu mber of devices that can be multidropped on each n etwork, eve n a medium-sized pla nt may have many n etwork cables running into the field, although substantially fewer than if poi nt-to-poi nt wiri ng was used. the field-level n etworks were therefore desig ned to en able very long wire runs and to allow field devices to take their power from the network. only asin gle pair of wires carries both the device powera s d thedigital com muni cati ons sig nal. this elimi nates the n eed for a separate power cable, thus keep ing the wiri ng simple and in expe nsive.as ano ther measure to keep costs dow n, desig ners chose a moderate field-level n etwork speed so no rmal in strume nt- grade cable could be used in stead of special data cable. no special conn ectors, couplers, or hubs are required either, which makes it possible to use rugged and weatherproof conn ecti ons.the grade of cable used for conven tio nal in strume nt conn ecti ons on most sites is more tha n sufficie nt for fieldbus n etwork ing. as a result, it is possible to reuse that cable when an existing plant is migrated to fieldbus. in hazardous process en vir onments where flammable fluids are prese nt in tri nsic safety is many times the preferred protecti on method. the field-level n etworks were therefore desig ned to allow safety barriers to be in stalled on the bus.because desig ners chose a moderate field-level n etwork speed the devices conn ected to it do not require a great deal of cpu process ing power to han dle the com muni cati on quickly. as a result, they also con sume very little power. because the low power con sumpti on results inlow voltage drop along the wire, it is therefore【篇二：毕业设计英文翻译模板】都信业设系别姓名专业班级学号息工程学院计英文翻译论文标题****学院大气探测、信***处、两个专业填写电子信息*******工程。
网站毕业设计外文翻译
WebsiteFrom Wikipedia, the free encyclopediaA website is a collection of related web pages, images, videos or other digital assets that are addressed relative to a common Uniform Resource Locator (URL), often consisting of only the domain name, or the IP address, and the root path in an Internet Protocol-based network. A web site is hosted on at least one web server, accessible via a network such as the Internet or a private local area network.A web page is a document, typically written in plain text interspersed with formatting instructions of Hypertext Markup Language (HTML, XHTML).A web page may incorporate elements from other websites with suitable markup anchors.Web pages are accessed and transported with the Hypertext Transfer Protocol (HTTP), which may optionally employ encryption (HTTP Secure, HTTPS) to provide security and privacy for the user of the web page content. The user's application, often a web browser, renders the page content according to its HTML markup instructions onto a display terminal.All publicly accessible websites collectively constitute the World Wide Web.the pages of a website can usually be accessed from a simple Uniform Resource Locator called the homepage. The URLs of the pages organize them into a hierarchy, although hyperlinking between them conveys the reader's perceived site structure and guides the reader's navigation of the site.Some websites require a subscription to access some or all of their content. Examples of subscription sites include many business sites, parts of many news sites, academic journal sites, gaming sites, message boards, web-based e-mail, social networking websites, and sites providing real-time stock market data.1.HistoryThe World Wide Web (WWW) was created in 1989 by CERN physicist Tim Berners-Lee.On 30 April 1993, CERN announced that the World Wide Web would be free to use for anyone.Before the introduction of HTML and HTTP, other protocols such as filetransfer protocol and the gopher protocol were used to retrieve individual files from a server. These protocols offer a simple directory structure which the user navigates and chooses files to download. Documents were most often presented as plain text files without formatting or were encoded in word processor formats.2.OverviewOrganized by function, a website may be（1）a personal website（2）a commercial website（3）a government website（4）a non-profit organization websiteIt could be the work of an individual, a business or other organization, and is typically dedicated to some particular topic or purpose. Any website can contain a hyperlink to any other website, so the distinction between individual sites, as perceived by the user, may sometimes be blurred.Websites are written in, or dynamically converted to HTML (Hyper Text Markup Language) and are accessed using a software interface classified as a user agent. Web pages can be viewed or otherwise accessed from a range of computer-based and Internet-enabled devices of various sizes, including desktop computers, laptops, PDAs and cell phones.A website is hosted on a computer system known as a web server, also called an HTTP server, and these terms can also refer to the software that runs on these systems and that retrieves and delivers the web pages in response to requests from the website users. Apache is the most commonly used web server software (according to Netcraft statistics) and Microsoft's Internet Information Server (IIS) is also commonly used.3. Static websiteA static website is one that has web pages stored on the server in the format that is sent to a client web browser. It is primarily coded in Hypertext Markup Language (HTML).Simple forms or marketing examples of websites, such as classic website, a five-page website or a brochure website are often static websites, because they present pre-defined, static information to the user. This may includeinformation about a company and its products and services via text, photos, animations, audio/video and interactive menus and navigation.This type of website usually displays the same information to all visitors. Similar to handing out a printed brochure to customers or clients, a static website will generally provide consistent, standard information for an extended period of time. Although the website owner may make updates periodically, it is a manual process to edit the text, photos and other content and may require basic website design skills and software.In summary, visitors are not able to control what information they receive via a static website, and must instead settle for whatever content the website owner has decided to offer at that time.They are edited using four broad categories of software:(1) Text editors, such as Notepad or TextEdit, where content and HTML markup are manipulated directly within the editor program(2) Wysiwyg offline editors, such as Microsoft FrontPage and Adobe Dreamweaver (previously Macromedia Dreamweaver), with which the site is edited using a GUI interface and the final HTML markup is generated automatically by the editor software(3) Wysiwyg online editors which create media rich online presentation like web pages, widgets, intro, blogs, and other documents.(4) Template-based editors, such as Rapidweaver and iWeb, which allow users to quickly create and upload web pages to a web server without detailed HTML knowledge, as they pick a suitable template from a palette and add pictures and text to it in a desktop publishing fashion without direct manipulation of HTML code.4. Dynamic websiteA dynamic website is one that changes or customizes itself frequently and automatically, based on certain criteria.Dynamic websites can have two types of dynamic activity: Code and Content. Dynamic code is invisible or behind the scenes and dynamic content is visible or fully displayed.(1) Dynamic codeThe first type is a web page with dynamic code. The code is constructed dynamically on the fly using active programming language instead of plain,static HTML.A website with dynamic code refers to its construction or how it is built, and more specifically refers to the code used to create a single web page. A dynamic web page is generated on the fly by piecing together certain blocks of code, procedures or routines. A dynamically-generated web page would call various bits of information from a database and put them together in a pre-defined format to present the reader with a coherent page. It interacts with users in a variety of ways including by reading cookies recognizing users' previous history, session variables, server side variables etc., or by using direct interaction (form elements, mouse overs, etc.). A site can display the current state of a dialogue between users, monitor a changing situation, or provide information in some way personalized to the requirements of the individual user.(2) Dynamic contentThe second type is a website with dynamic content displayed in plain view. Variable content is displayed dynamically on the fly based on certain criteria, usually by retrieving content stored in a database.A website with dynamic content refers to how its messages, text, images and other information are displayed on the web page and more specifically how its content changes at any given moment. The web page content varies based on certain criteria, either pre-defined rules or variable user input. For example, a website with a database of news articles can use a pre-defined rule which tells it to display all news articles for today's date. This type of dynamic website will automatically show the most current news articles on any given date. Another example of dynamic content is when a retail website with a database of media products allows a user to input a search request for the keyword Beatles. In response, the content of the web page will spontaneously change the way it looked before, and will then display a list of Beatles products like CD's, DVD's and books.5. Software systemsThere is a wide range of software systems, such as Java Server Pages (JSP), the PHP and Perl programming languages, Active Server Pages (ASP), Yuma and ColdFusion (CFML) that are available to generate dynamic web systems and dynamic sites. Sites may also include content that is retrievedfrom one or more databases or by using XML-based technologies such as RSS.Static content may also be dynamically generated either periodically, or if certain conditions for regeneration occur (cached) in order to avoid the performance loss of initiating the dynamic engine on a per-user or per-connection basis.Plugins are available to expand the features and abilities of web browsers, which use them to show active content, such as Microsoft Silverlight, Adobe Flash, Adobe Shockwave or applets written in Java. Dynamic HTML also provides for user interactivity and real time element updating within web pages (ie pages don't have to be loaded or reloaded to effect any changes), mainly using the Document Object Model (DOM) and JavaScript, support which is built-in to most modern web browsers.Turning a website into an income source is a common practice for web developers and website owners. There are several methods for creating a website business which fall into two broad categories, as defined below.(1) Content-based siteSome websites derive revenue by selling advertising space on the site (see Contextual advertising).(2) Product- or service-based sitesSome websites derive revenue by offering products or services for sale. In the case of e-commerce websites, the products or services may be purchased at the website itself, by entering credit card or other payment information into a payment form on the site. While most business websites serve as a shop window for existing brick and mortar businesses, it is increasingly the case that some websites are businesses in their own right; that is, the products they offer are only available for purchase on the web.Websites occasionally derive income from a combination of these two practices. For example, a website such as an online auctions website may charge the users of its auction service to list an auction, but also display third-party advertisements on the site, from which it derives further income.网站文章来自维基百科，自由的百科全书网站是一组相关的网页，图片，视频或其他数字资产的集合，是针对相对的一个共同的统一资源定位符（URL），这个定位器往往由域名，或组成的IP地址在以网络为基础的互联网协议上的根路径构成。
毕业设计英文翻译中英文对照版
Feasibility assessment of a leading-edge-flutter wind power generator前缘颤振风力发电机的可行性评估Luca Caracoglia卢卡卡拉克格里亚Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering Center, 360 Huntington A venue, Boston, MA 02115, USA美国东北大学土木与环境工程斯内尔工程中心400，亨廷顿大道360，波士顿02115This study addresses the preliminary technical feasibility assessment of a mechanical apparatus for conversion of wind energy. 这项研究涉及的是风能转换的机械设备的初步技术可行性评估。
The proposed device, designated as ‘‘leading-edge-fl utter wind power generator’’, employs aeroelastic dynamic instability of a blade airfoil, torsionally rotating about its leading edge. 这种被推荐的定义为“前缘颤振风力发电机”的设备，采用的气动弹性动态不稳定叶片翼型，通过尖端旋转产生扭矩。
Although the exploitation of aeroelastic phenomena has been proposed by the research community for energy harvesting, this apparatus is compact, simple and marginally susceptible to turbulence and wake effects.虽然气动弹性现象的开发已经有研究界提出可以通过能量采集。
本科毕业设计翻译英文
( 1. Faculty of Civil Engineering & Geosciences, Delft University of Technology , P. O. Box 5048,2600 GA Delft, t he Nether lands; 2. Key Laboratory of Silicate Materials Science and Engineering of the Ministry of Education, Wuhan University of Technology, Wuhan 430070, China)Abstract: Coal tar, a by- product from the destructive distillation of coal in co king oven, is widely used in road engineering for its excellent adhesion and fuel resistance properties, especially for pavement surface treatments in gas stations and airports.However, coal tar has a high Poly cyclic Aromatic Hydro carbons ( or PAHs) content, which makes it toxic.I n 1985, the International Agency for Research on Cancer ( IARC) has proved that coal tar is carcinogenic to humans. Research showed that Coal Tar- based Sealers ( CTS) contribute to the majority of PAHs pollution in the water environment. Because of this environmental concern, CT S are not allowed in many dev eloped countries in the USA and Europe. In contrast, coal tar is still used for road engineering in China and is even used increasingly .This paper gives a literature review on the general information and research about environmental concern of using coal tar in road engineering. Based on the review , some possible alternatives to replace coal tar are described. These alternatives include nanoclay/ epoxy modified bitumen/ bitumen emulsion and waterborne polyuret hane/ epoxy resin, which are environmental friendly. They have the potential to perform as w ell as CTS, and even better in some special applications.Key words:coal tar; pavement surface treatment; adhesion property; poly cyclic aromatic hydrocarbons; modified bitumen emulsionCLC number: U 416 Document code: A Article ID: 1671- 4431( 2010) 17- 0001- 07Received date: 2010- 05- 07.Biography : Xiao Y( 1986- ) , Ph D Candidate. E-mail: yue. xiao@1 introductionTwo basic types of binders are currently used in the pavement surface treatment market: coal tar-based and bitumen-based. At some places like g as stat ions and airports, coal tar-based surface sealers performed much better than bitumen-based sealers with regards to adhesion properties and chemical resistance. Coal tar-based have better resistance to petroleum oils and inorganic acids, and have better moisture resistance[ Austin, 2005] .Because of these out standing properties, CTS are widely used in road engineering for pavement surfacetreatment for many years. However, coal tar is a complex hydrocarbon mixture consisting of hundred of PAH[SCHER, 2008] . These PAHs are toxic and considered human carcinogens. Because of it s environmental unfriendly properties, coal tar is not allowed in most of the developed counties like the Netherlands. In the Netherlands,use of tar containing product s is not allowed since 20 years, with one temporary except ion for antiskid runways in airfields [ van Leest , 2005] . But after 2010, it w ill not be allowed for airport pavement application anymore. Compared to these bans, coal tar is still used for road engineering in China. China Coal Tar Industry Report mentioned that the coal tar consumption w ill be on the upward t rend [CCTIR, 2008] .Based on new technologies like nano technology and two-component technology, other materials are developed for pavement surface treatment and they perform w ell. Modified bitumen emulsions, which can be applied at low temperatures, were successfully used in South Africa, Australia and many other countries. Additives such as polymers ( SBS, SBR and EVA ) , clays ( illite, kaolinite and montmorillonite ) are known to improve the properties of bitumen emulsions in special road applications [ TRB-EC102, 2006;Xiao, 2010] . With the waterborne two-component technology, coating manufacturers can producehigh-performance sealers and achieve the same or better properties than solvent-based sealers. Furthermore, waterborne resins for coating s usually do not contain or just contain a small amounts of other solvent s, indicating that waterborne two component systems are environmental friendly. Epoxy modified bitumen w as originally developed in the late 1950s by Shell Oil Company as a material designed to withstand fuel exposure [ Thom, 2006] . After full curing , epoxy modified bitumen mixture has high temperature stability and strength, excellent fatigue, superior adhesion and rutting resistance.In this paper, a short literature review is given on the use and properties of CTS for pavement surface treatment and its environmental concern. After that several possible alternatives are discussed, such as nanoclay modified bitumen emulsion, epoxy modified bitumen, waterborne polyurethane/ epoxy resin. These alternatives may have good properties and are environmental friendly.2 Use and Advantages of Coal Tar Based SealersCoal tar-based products are used in many industries, for example pavement engineering, the building industry and medical treatment s. In pavement engineering , one of the largest applications is CTS.Coal tar can be used as a binder and filler in surface treatment formulations, and as a modifier for epoxyresin surface coating s. T he streets of Baghdad w ere the first to be paved with tar from the 8th century AD. Tar was a vital component of the first sealed, or tarmac roads. The first tar macadam road with a tar-bound surface was placed in 1848 out side Nottingham, England. In Washington D. C. some of thetar-bound surface courses have a service life of about 30 years.Coal tar is a very complex mixture of chemicals. It s molecular structure is quite different from bitumen.Some of the constituents are described as PAHs. Being stable in molecular structure, these chemicals are incompatible with oil and gas, and provide a barrier coat to protect asphalt surfaces against the destructive effects of petroleum based products and chemicals [Aust in, 2005] . CTS have a better chemical resistance than bitumen based, extremely low permeability to moisture and a high resistance to ultraviolet radiation. These properties make it ideally suited for parking areas w here concentrations of oil and gasoline leaks are prevalent, like gas stations, truck and bus terminals and airport s. CTS are used to extend the life and reduce maintenance cost associated with asphalt pavements, primarily in asphalt road pavement. They are typically used at airports for aprons, taxiways and runways. The Federal Aviation Administration Advisory Circular 150/ 5370-10A Standards for Specifying Construction of Airports include a requirement for pavement sealers that they should contain at least 35% coal tar in runway asphalt pavement.The reason for this requirement is that CTS have a much better resistance to jet fuel than bitumen-based sealers [Austin, 2005].3 Environmental ConcernGenerally, coal tars consist of a mixture of many organic compounds, like benzene, toluene, phenol, naphthalene, anthracite , and others. The risk assessment of coal tar is largely based on PAHs, especially on Benzo (a) pyrene . PAHs are the most relevant component s in terms of toxicity in coal tarproducts[ SCHER, 2008] .3. 1 Polycyclic aromatic hydrocarbonsPolycyclic aromatic hydrocarbons are also known as polycyclic aromatic compounds, polyaromatic hydrocarbons or as polynuclear aromatics. PAHs are a group of over 100 different chemicals consisting of carbon and hydrogen in fused-ring structures. T able 1 shows several typical chemical structures of PAHs. PAHs are highly toxic and harmful to human and ecosystem health [Austin, 2005] . The content of PAHs in coal tar increases as the carbonization temperature increases.3.2 Environmental riskIn 1985, IARC has pointed out that coal tar pitches are carcinogenic in humans [IARC, 1985] . In 2008,three scientific commit tees ( SCCP, the Scientific Commit -tee on Consumer Products; SCHER, the Scientific Committee on Health and Environmental Risks; SCEN IHR, the Scientific Commit tee on Emerging and NewlyIdentified Health Risks) concluded that cancer risk was the most serious point of coal tar s risk characterizations [ SCHER, 2008] . Occupational exposure to coal tar increases the risk of developing skin cancer and other tissue sites , like lung, bladder, kidney and digestive tract . According to the IARC, products that include more than 5 percent of crude coal tar are Group 1 carcinogen which has sufficient evidence of carcinogenicity in humans. So, many countries all over the world have eliminated it s usage.In 2003, scientist s from the city of Austin ( USA ) identified CTS as a significant source of PAHs contamination. The United States Geological Survey and Austin City have conducted additional research that corroborates this finding, concluding that coal tar sealants are responsible for the majority of PAHs pollution in water environment in the Austin area. Coal tar-based pavement sealers are considered as a source of urban water pollution. These are long-lasting substances that can build up in the food chain to harmful levels to humans. Based on their investigations, Austin became the first city in the USA to ban the use of CTS for pavements [ Austin,2005; Mahler, 2005] .As a precaution, in Germany, manufacturers have voluntarily agreed to ban coal tar from their product s. In the Netherlands, coal tar containing products did not meet the Dutch Environmental Standards and w ill not be allowed for airport pavement after 2010.4 Possible AlternativesAccording to these environmental concerns, alternatives are required. These alternatives should have atleast comparable or better properties than CTS. At the same time, they should be environmental friendly. In this section, the possible use of modified bitumen emulsions, epoxy modified bitumen and waterborne resins are discussed.4. 1 Modified bitumen emulsionsBitumen emulsions are heterogeneous systems with two or more liquid phases, consisting of a continuous liquid phase ( water ) and at least one second liquid phase ( bitumen) dispersed in the former as fine droplets [ TRB-EC102, 2006] . Standard bitumen emulsions are normally considered to be of the oil in water type and contain from 40% to 75% bitumen, 0. 1% to 2. 5% emulsifier, 25% to 60% water plus some minor components. The bitumen droplets rang e from 0. 1 to 20 micron in diameter.4. 1. 1 Properties of modified bitumen emulsionsUnlike bitumen, bitumen emulsions do not need to be heated at high temperatures before application. Temperature storage and application at ambient temperature can avoid the use of energy and emissions associated with heating and drying [Kennedy, 1997]. This makes bitumen emulsions more economic and environmental friendl , compared to coal tar-based products.Additives are used to improve the properties of bitumen emulsions in special road applications. Polymer( SBS, SBR and EVA) , clay illite , kaolinite and montmorillonite and epoxy modified bitumen/ bitumen emulsions were successfully used in South Africa and Australia [ TRB-EC102, 2006; Xiao, 2010] .During the application of bitumen emulsion, the water must be separated from the bitumen phase and evaporate.This separation is called breaking. After complete evaporation of the water, the bitumen particles will coalesce and bond together to develop mechanical properties. This strength development is curing.4. 1.2 nanoclay modified bitumen emulsionThe most preferred and widely used nanoclays are organically modified smectite clays with a 2: 1-type layey structure such as montmorillonite, saponite, etc [ Ammala , 2007] . All these layered silicates have the same crystalline structure and normally have a thickness of about 1 nanometer and a length of about 50 ~ 1 000 nanometers.In nanoclay modified bitumen emulsion, three possible particle dispersions can be distinguished as Fig. 1 shows [Xiao, 2010]. In the case of type one (see Fig. 1( a) ) , all the nanoclay particles are dispersed in the bitumen droplets. In this case, after breaking and curing the particles are dispersed in the binder between the aggregates. In the second type (see Fig. 1( b) ) , all of the nanoclay particles are dispersed in the water phase. After breaking and full curing, the particles are surrounding at the boundaries of the bitumen droplet s. The third type( see Fig. 1( c) ) is a combination of the first two types. Some of the particles are dispersed in the bitumen droplets while the others are dispersed in the water phase. In this condition, after breaking and curing the nanoclay particles both occur in the binder and between the bitumen droplets.These dispersion types have a significant influence on the properties of bitumen residues. Further investigations need to be carried on for checking these dispersions.Fig . 2 shows the possible outstanding properties of nanoclay modified bitumen emulsion on outside chemical resistance [Xiao, 2010] . With the unmodified bitumen emulsion after curing on the pavement surface, fuel, moisture and ultraviolet radiation can affect the binder directly. These can decrease the performance and cause raveling and ageing problems. When nanoclay modified bitumen emulsions are used for surface treatment, four steps can be dist inguished during breaking and curing. First, nanoclay modified bitumen emulsion consist s mainly of water, bitumen drop and nanoclay layers. Second, the water phase evaporates during the breaking and curing process. Then, bitumen droplets adhere to nanoclay particles, causing clusters to form the binder. At the last, binder is formed with nanoclay layers inside.The dispersed nanoclay particles can decrease surface damages due to fuel, moisture, air, etc. to a certain extent, resulting in better chemical and ageing resistance.4.2 Epoxy modified bitumensThe epoxy modified bitumen binder is a two phase chemical system in which the continuous phase is an acid cured epoxy and the discontinuous phase is a mixture of specialized bitumens, which makes the mixture performdifferent from a traditional asphalt mixture.4. 2. 1 Properties of epoxy modified bitumensEpoxy modified bitumen was used for pavement treatment long time ago and has achieved better properties than unmodified bitumen. In 1967, it was used to strengthen the surface of San Francisco Bay smile-long San Mateo-Hay ward Bridge. After more than 40 years, the bridge surface is reported to be in excellent condition.The special structure of epoxy modified bitumen makes it perform different from traditional bitumen. It does not become brittle at low temperature and does not melt at high temperature. Epoxy modified bitumen is a flexible material that can be applied in thin surface layers. When used on roads, it sets quickly enough to allow early traffic even before full curing, which enables the road to be reopened withintwo hours [ Xiao, 2010] .Epoxy modified bitumen is reported to be extremely durable as w ell as flexible. Surfaces with epoxy modified bitumen obtained better skid resistance and produce less noise than bitumen based sealers. Epoxy modified bitumen has extremely high temperature stability and strength, superior rutting resistance, excellent adhesion properties, high resistance to surface abrasion and is sufficiently fuel resistance [ Elliot t, 2008; Xiao, 2010] .4.2.2 Two-component epoxy modifiedbitumenTwo-component epoxy modified bitumen is acold mix application material. It is a two componentreactive material based on two components. One is amix of bitumen, bitumen-compatible epoxides andadditives. The other one is a mix of hardeners. After mixing of these two component s, there will be a fast react ion leading to epoxy resin within a bitumen based matrix.The tensile strength of Esha Seal 2C, which is a kind of two-component epoxy modified bitumen, obtained from ICOPAL BV, was evaluated using the Direct T ensile Test . Fig. 3 shows the tensile strengthafter different curing times and temperatures.Results indicate that the curing rate of epoxy modified bitumen emulsion depends on the curing temperature. The tensile strength increases with increasing curing time temperature . The tensile strength after full curing is higher than thetensile strength of bitumen, which implies that roads can be reopened for traffic very quickly w hen epoxy modified bitumens are applied in the surface layer.4. 3 Waterborne resinsWaterborne resins use water as the main volatile liquid component . It always shows good adhesion and the resistance to fuel, water and chemical is good. New technologies in waterborne systems provide unique technical solutions to get good properties, such as good adhesion to concrete and acidic resistance. With the waterborne two-component technology, coating manufacturers can formulate high-performance coatings without a cosolvent and achieve the same or better properties. Here waterborne polyurethane and epoxy resins will be discussed.4. 3. 1 Waterborne polyurethane resinsPolyurethane is a polymer consisting of a chain of organic units joined by urethane carbamate links. Polyurethane resins are formed from the reaction of an isocyanate with compounds containing active hydrogen, as Fig.4 shows. When the two components are mixed the hydroxyl groups ( - OH) in the resin react with the isocyanate groups ( N=C=O) in the hardener and a three dimensional molecular structure is produced[Weiss, 1997] .Because only one isocyanate group can react with one hydroxyl group, it is possible to vary the ratio of hydroxyl groups and isocyanate groups slightly either w ay in order to modify the mechanical properties of the system.Basically, waterbornepolyurethanes can be described asreactive or non-reactive polymerscontaining urethane and urea groupswhich are stabilized in water byinternal or external emulsifiers. Thesedifferent hydrophilic modify cationsallow the production of stablewaterborne polyurethanes with average particle sizes between 10 nm and 200 nm. Waterborne polyurethane resin is a water-based aliphatic polyurethane emulsion.Waterborne polyurethanes are environmental friendly. They provide a tough, durable and highly flexible binder. The advantages associated with polyurethane coatings are their high tensile strength, excellent adhesion properties and chemical/ mechanical resistance. Properties of waterborne polyurethanes can be improved by adding modifiers, such as organoclay layers [ Kim, 2003; Xiao, 2010] .Addagrip 1000 System resin is a two-component polyurethane resin designed by Addagrip Surface Treatments UK Ltd. It can be used for sealing to protect asphalt surfaces from erosion caused by frostdamage, chemical at tack and aviation fuel spillage. Areas treated over the last twenty years at military and civil air fields have prevented further deterioration and increased the service life of the concrete pavement by an estimated 10~ 15 years. Table 2 show s the properties of the samples before and after surface treatment with Addagrip 1000 System resin. 10 cm x 10 cmx10 cm blocks w ere used. The sample surfaces w ere heated and dried by a hot compressedair system before the resin w as sprayed onto the surface [Addagrip Ltd. ] . After surface reatment with this kind of polyurethane resin, the water and fuel resistance can be improved significantly.4. 3. 2 Waterborne epoxy resinsEpoxy is a copolymer. It is formed from two different chemicals, the resin and the hardener. Most common epoxy resins are produced from a reaction between Epichlorhydrin and bispheno-l A, see Fig.5[Weiss,1997] .Waterborne epoxy resin, with excellent adhesion properties, is another possible alternative. Waterborne epoxy resin is a stable resin material prepared by dispersing epoxy resin in the form of particles or droplet s into the dispersion medium based on water as a continuous phase.Application ofwaterborne epoxy resinsis not onlyconvenient but alsocauses no pollution tothe environmentand no harm to thehuman body. Afteradding a properamount of curing/ solidifying agent, advantages like high strength ,high-temperature resistance, chemical resistance, fatigue resistance, and high antiaging ability can be achieved [ Xiao, 2010; Weiss, 1997]5 ConclusionCTS are widely used for pavement surface treatments because of their excellent adhesion properties and good fuel resistance. How ever, because of their high PAHs content s, which are considered as human carcinogens, CTS are not allowed anymore in some of the developed counties. In order to eliminate the significant threat of pollution to our environment, w e should stop using CTS. Instead, modified bitumen emulsions, epoxy modified bitumen, waterborne polyurethanes and waterborne epoxy resins could achievecomparable or better properties than CTS. All of them have good adhesion, excellent chemical and ageing resistance. Epoxy modified bitumen has extremely high temperature stability and strength. Application of waterborne resins is convenient and the curing rate can be easily adjusted by changing the ratio of chemical components. And, the most important, these alternatives are environmental friendly.AcknowledgementsThe scholarship from the China Scholarship Council is acknowledged. T he authors would like to express thanks to ICOPAL BV for their materials and technical supports.References[1] AddagripLtd.www .adda grip [2] Ammala A, Hill A J.Poly( M-Xylene Adipamide)-Kaolinite and Poly( M-XyleneAdipamide)-Montmorillonite Nanocomposites [J] . Journal of Applied Polymer Science, 2007(104):1377- 1381.[3] Austin. http: / /www .ci. austin. tx . us/ watershed/ coaltar- ban. htm. Austin Bans Use of Coal Tar Sealants-first in Nation,2005.[4] CCTIR.China Coal Tar Industry Report 2006-2010.[R],2008.[5] Elliott R. 2008. Epoxy Asphalt: Concept and Properties. Workshop of TRB 2008.[6] IARC. Polynuclear Aromatic 4 Bitumens , Coal Tars and Der ived Products,Shale Oils and Soots. IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Humans,Vol. 35. Lyon, France:International Agency for Research on Cancer,1985.[7] Kennedy J. Alter native Materials and Techniques for Road Pavement Construction[R] . London: DOE Energy Efficiency Office,1997.[8] Kim B K, Seo J W, Jeong H M. Morphology and Properties of Waterborne Polyurethane/ clay Nanocomposite [J]. European[9] SCHER. Scientific Committee on Health and Environmental Risks. Coal tar pitch, high temperature Human Health Part. CAS No: 65996- 93- 2. EINECS No: 266- 028-2.[10] Thom N H. Asphalt Cracking: A Nottingham Perspective [J].Engenaria Civil/ Civil Engineering, 2006(26) : 75- 84.[11] TRB-EC102. Asphalt Emulsion Technology. Transportation Research Board[S], 2006.[12] Van Leest A J, Gaar keuken G. The F O D. Resistance of Sur face Layers on Airfields in the Netherlands; in Situ and Laboratory Testing [R] . 2005 European Airport Pavement Workshop, 2005. [13] Van Metre P C, Mahler B J. Trends in Hydrophobic Organic Contaminants in Urban and Reference Lake Sediments Across the United States, 1970- 2001[J]. Environmental Science and Technology,2005, 39( 15) : 5567- 5574.[14] Weiss K D. Paint and Coatings: A Mature Industry in Transition [J].Progress in Polymer Science, 1997, 22(2):203- 245.[15] Xiao Y. Literature Review on Possible Alternatives to Tar for Antiskid Layers . Delft University o f Technology, Road and Railway Engineering Section[R] . Report No.7-10-185-1,the Nether lands.。
毕业设计英文翻译
装载机发展概况A loader is a type of construction equipment (engineering vehicle) machinery that is primarily used to "load" material into another type of machinery (dump truck, conveyor belt, rail-car, etc.).Loaders are used mainly for uploading materials into trucks, laying pipe, clearing rubble, and digging. A loader is not the most efficient machine for digging as it cannot dig very deep below the level of its wheels, like a backhoe can. Their deep bucket can usually store about 3-6 cubic meters of earth. The front loader's bucket capacity is much bigger than a bucket capacity of a backhoe loader. Loaders are not classified as earthmoving machinery, as their primary purpose is other than earthmoving.Unlike most bulldozers, most loaders are wheeled and not tracked, although track loaders are common. They are successful where sharp edged materials in construction debris would damage 2 rubber wheels, or where the ground is soft and muddy. Wheels provide better mobility and speed and do not damage paved roads as much as tracks, but provide less traction.Unlike standard tractors fitted with a front bucket, many large loaders do not use automotive steering mechanisms. Instead, they steer by a hydraulically actuated pivot point set exactly between the front and rear axles. This is referred to as "articulated steering" and allows the front axle to be solid, allowing it to carry greater weight. Articulated steering provides better maneuverability for a given wheelbase. Since the front wheels and attachment rotate on the same axis, the operator is able to "steer" his load in an arc after positioning the machine, which can be useful.The loader assembly may be a removable attachment or permanently mounted. Often the bucket can be replaced with other devices or tools--for example, many can mount forks to lift heavy pallets or shipping containers, and a hydraulically-opening "clamshell" bucket allows a loader to act as a light dozer or scraper.The wheel loader is a type of engineering vehicle used primarily to move crude material over shorter distances. As the vehicle is designed without wheel suspension, wheel oader drivers are exposed to high levels of whole body vibration which influences ride comfort negatively.Construction machines, sometimes referred to as engineering vehicles or earth movers, are basically a class of self-propelled machines designed for use in civil engineering. The work in this thesis concerns a special class of construction machines, the wheeled loader. This vehicle is essentially a type of tractor equipped with permanently attached, front mounted lifting arms operated by hydraulic cylinders. Unlike vehicles designed primarily for transport, the wheel loader is built without any axle suspension. The front wheels are attached directly to the vehicle body, and the rear axle is allowed to oscillate around the longitudinal axis, thus allowing all wheels to maintain contact with the ground. An example of a medium sized wheel loader is shown in figure 1.Wheel loaders are mainly used in construction or surface mining for moving crude material over shorter distances, but because of the versatility of the machines they are also commonly used for pallet handling, timber loading and similar tasks. Since the advent of the first purpose-built wheel loader about 50 years ago, considerable effort has been made to improve the efficiency, safety and operability of the vehicle. However, less attention has been given to issues like ride vibrations or handling stability. Traditionally, wheel loaders have been seen as machines more than vehicles and so the driving dynamics have been considered less important. However, since the demands for increased task performance and operator comfort are continuously growing, future requirements for vibration isolation and highspeed transport capacity will call for suspension systems that allow safe and comfortable travel under a range of operating conditions. This means that vehicle dynamic considerations are becoming increasingly important in the design of wheel loaders.As a consequence of the primitive vehicle design and the rough surfaces where wheel loaders are usually operated, wheel loader drivers are often exposed to high levels of whole body vibration. In short-term perspective these vibrations will affect operator comfort negatively and cause driver fatigue. Long term exposure to low frequency vibrations has been shown to increase the risk for lower back pain , and is also believed to be the cause of various internal organ disorders. Thus, whole-body vibration can be considered a major occupational hazard for earth mover operators and have been the focus of various legislations such as the European Vibration Directive . As the wheel loader does not have any axle suspension, primary isolation from ground induced vibrations is provided by the tyres. Earth mover tyres are typically large and soft, thus filtering out and absorbing some of the vibrations and shocks caused by ground roughness. Theoretically, tyres could be engineered to dampen higher amounts of vibration although this would in reality be highly impractical. According to Lines etal [3], tyres would have to absorb about five to ten times more vibration energy in order to fully protect the operator from ground induced vibrations. This would greatly affect the rolling resistance of the tyre and hence the energy consumption of the vehicle would increase as well. Furthermore, the larger energy absorption would lead to high thermal and mechanical stress in the tyre material, which would accelerate wear. It is obvious that tyre design for increased vibration isolation would soon conflict with economic and environmental considerations. Cab and seat suspensions also function to reduce operator vibration levels. The cab is usually mounted on rubber elements, sometimes combined with an integrated oil volume, thus providing vibration isolation through flexibility and viscous damping. More refined cab suspensions also exist where the cab is mounted on a suspended subframe [4]. High-end driver seats are commonly designed with hydraulic or pneumatic dampers to cushion the driver from vibrations and shocks. The main imitation of seat and cab suspensions is the small amount of suspension stroke available. Because of these lim itations, the stiffness coefficien t of the flexible elements needs to be high enough to avoid impacts with suspension ends at large transient loads, and therefore the eigenfrequency of the cab or seat suspension is generally too high to provide vibration isolation in the lower frequency range. Furthermore, cab and seat suspensions mainly reduce vibrations in the vertical direction. This could possibly be alleviated by active systems [5], although the potential of advanced seat technology is Vehicle dynamic analysis of wheel loaders with suspended axles still unclear. It should also be noted that the vibration isolation of the seat is often reduced by inadequate operator posture . In addition to cab and seat suspensions,larger wheel loaders are commonly fitted with a lifting arm suspension system to decouple the mass and inertia of the lifting arms from the vehicle body. The bucket and lifting arms are isolated from the vehicle by means of gas springs incorporated in the lifting hydraulics and thereby pitching and vertical oscillations to some extent, mainly for a loaded vehicle. Considerably greater vibration isolation can be provided by designing the wheel loader with full wheel suspension. This would mean flexibly attaching the wheels to the vehicle body by means of springs and dampers, as on virtually all road vehicles and on most offroad vehicles. Axle suspensions have greater potential for improved ride comfort as the available suspension travel is larger, and also have the potential to alleviate vibrations in the lateral and longitudinal directions in ways not possible by cab and seat suspensions. Apart from reducing driver exposure to vibrations, axle suspensions could also improve the task performance of the loader. As theefficiency of an earth mover is usually defined by the volume of material that can be transported in a specified time, the working performance is directly related to the maximum practical velocity of the vehicle. This velocity is currently limited to a large extent by the operator’s ability to withstand vibrations and therefore shielding the operator from vibrations will in practice increase the attainable vehicle speed. An axle suspension also functions to reduce wheel load fluctuations, thus improving handling quality and manoeuvring stability at high speeds. Therefore suspended axles are not only beneficial for driver comfort but also for the performance of the vehicle.. With the inclusion of suspended wheel axles, a large part of the vehicle mass will be oscillating on the axle suspension rather than simply the tyre flexibility. This will clearly have an impact on the driving dynamics of the vehicle.Naturally, the increased complexity of the vehicle will also add to overall cost and maintenance needs, which is not an unimportant consideration. Suspended axles have been used on certain engineering vehicles for some time, mainly off-highway dump trucks which utilise rubber springs or hydropneumatic struts as suspension elements. On agricultural tractors, suspended front axles are becoming increasingly common and some models feature rear axle suspension as well [6]. Applications to loader vehicles are less common and have mainly been limited to military models that are equipped with suspended axles to enable high speed road travel, thereby allowing rapid deployment and increased combat survivability [7, 8]. Since previous information regarding wheel loader suspension design is limited, a review of the applicability of current design methods, as well as the development of new methodology, is required to provide the necessary knowledge for wheel loader suspension design.In construction areas loaders are also used to transport building materials - such as bricks, pipe, metal bars, and digging tools - over short distances.Loaders are also used for snow removal, using their bucket or a snowbasket, but usually using a snowplow attachment. They clear snow from streets, highways and parking lots. They sometimes load snow into dump trucks for transport.Front loaders gained popularity during the last two decades, especially in urban engineering projects and small earthmoving works. Many engineering vehicle manufacturers offer a wide range of loaders, the most notable are those of John Deere,Caterpillar, Case, Volvo, Komatsu and Liebherr.The following we will introduce Carter 938G Series II Wheel Loader.EngineThe 938G II provides more power, excellent fuel economy, and reduced maintenance.Turbocharged, ATAAC. Turbocharging packs dense air into the cylinders for more complete combustion and lower emissions. Air-to-air aftercooling (ATAAC) provides a separate cooling system for intake manifold air. The ATAAC system reduces smoke and emissions by providing cooler inlet air for more efficient combustion.Constant Net Horsepower. The 938G II’s electronic engine is integrated with an on-demand cooling fan. The engine compensates for varying fan loads and provides constant net horsepower, regardless of operating conditions. A consistent level of “working”horsepower is provided and fuel consumption is reduced.Oil Change Intervals. The engine oil change interval is increased to 500 hours (with CH-4 oil), reducing costs and downtimePowerful Performance. The 3126B ATAAC engine delivers net power of 119 kW (160 hp), and meets EPA Tier 2 emissions standards. Its advanced system keeps fuel at low pressure in the fuel lines until it is injected into the cylinder. Fuel pressure is created hydraulically in response to a signal from the ADEM III™Electronic ControlModule.Electronic Control Module. The Advanced Diesel Engine Module (ADEM III) fuel system is a proprietary electronic control module, which provides improved engine response and fuel efficiency,plus advanced diagnostics and reduced emissions. Altitude capability is increased to 3050 meters (10,000 feet) without derating. ADEM III allows full electronic integration of the engine and transmission for maximum power train efficiency.Power TrainAdvanced Caterpillar power train is reliable and fuel efficient.Electronic Power Shift Transmission.The electronic power shift transmission with automatic shift capability is a countershaft design built by Caterpillar. It is electronically controlled and allows full power shifts and directional changes. Fully modulated gear shifts contribute to operator comfort and increase component life.Electronic Clutch Pressure Control (ECPC). Senses input from both the transmission and the operator controls in the cab to modulate each individual clutch through a proportional electro-hydraulic valve. This results in smoother gear changes and improved shift quality. Energy is modulated into the clutches, resulting in longer clutch life.Integrated Braking System. New for G Series II, IBS integrates downshifting and transmission neutralization into the left-hand brake pedal. IBS provides smooth, optimized transmission neutralizer performance with a greater range of adjustability. The Integrated Braking System also lowers owning and operating costs by reducing axle oil temperatures, which can extend service brake life.Easy Service. Daily transmission oil level check is done from the ground through a well-protected sight gauge.An oil sampling valve allows quick,clean access to the transmission for S•O•SSM oil analysis.Cooling SystemNew G Series II cooling package reduces radiator plugging and improves fuel efficiency.Reverse Flow. Air enters through the rear grill and exits out the top opening and side hood doors. Rear air flow picks up less debris from the ground, reducing plugging.Improved System Access. The 938G II adds a swing-out grill, hydraulic oil cooler and air conditioner condenser for easier cleaning. Side panels open to allow access to both sides of all cores for cleaning. A heavy duty Airborne Debris Grill, with 4 mm perforations is available as an attachment.On-Demand Fan. Electronically controlled, variable speed on-demand fan adjusts to meet the varying cooling requirements of the machine. Fan speed is determined by oil, coolant and inletmanifold temperatures. In cooler operating conditions, average fan speed is reduced, resulting in less fuel consumption, lower noise levels and less radiator plugging.Unit Core Radiator. New unit core radiator with square wave shaped fins.Lower fin density (6 fins per inch) allows debris to pass through more easily.Environmental FeaturesCaterpillar cares about the environment and continues to develop innovative solutions.Low Exhaust Emissions. The Cat 3126B ATAAC engine used in the 938G Series II is a low emission engine designed to meet Tier 2 emission regulations. It is electronically controlled, with air-to-air aftercooling for more efficient combustion and cleaner emissions.Reduced Sound. The electronic on-demand fan automaticallyregulates fan speed depending on cooling requirements. The fan draws less horsepower in cooler ambient temperatures, which reduces fuel consumption.Sound levels are also reduced when the fan slows down.There is additional insulation around the engine to reduce sound levels.Environmental Fluids. Extended Life Coolant/Antifreeze with anti-foaming and anti-corrosion properties provide extended service intervals (up to 6000 hours) and requires less frequent fluid changes and disposals. Air conditioning refrigerant is CFC-free.Operator Station1 Steering. Low effort hand metering unit steering. Tilt steering column helps fit the wheel to the operator. Load sensing steering directs power through the steering system only when needed. When not steering, more engine power is available to generate rimpull, breakout and lift forces.2 Excellent Visibility. The front window provides remarkable forward and peripheral viewing, including the machine wheels and bucket corners. Bonded glass in the windshield eliminates frame obstructions.The sloping hood provides excellent visibility to the rear of the machine.3 Finger Tip Controls. New pilot-assisted hydraulic implement controls deliver comfortable, low-effort operation. Single lever joystick and lift lever F-N-R switch are available as attachments.4 New Instrument Cluster. Gauges, status indicators and alert indicators are now centrally located. 3-level warning system monitors key functions. The system alerts the operator of immediate or impending problems with engine oil pressure, parking brake, fuel pressure,electrical system, brake oil pressure,hydraulic oil temperature, transmission filter bypass, engine inlet manifold temperature, primary steering oil pressure and the air inlet heater. LED warning indicators with no bulbs to replace.5 Cab Access. Left and right side doors swing open 180 degrees and latch for optimal ventilation, visibility and communication to ground level. Left and right side sliding windows are available as an attachment. Full service platforms are provided on both sides of the machine for safety and easy maintenance access.6 Floor Mounted Pedals. All pedals including the new electronic governor,are floor mounted for greater operator comfort. Left pedal incorporates the new Integrated Braking System that combines service brake, transmission neutralizer and downshift functions.7 Generous Storage partments for lunchbox, coolersand cups.8 Seat Options. The standard cloth and vinyl seat adjusts 6 ways. A new Caterpillar Contour air suspension seat (attachment) provides increased operator comfort with 6-way adjustment and automotive-style lumbar support.9 Electronic Autoshift Control. Set for manual or one of two fully automatic shifting modes.10 Ride Control System Switch.Attachment that reduces fore and aft pitch for a smoother, more comfortable ride. Allows the selection of three different modes: Off –always off service. On –always in service.Auto –the system is automatically actuated when themachine travels at a speed greater than 9 km (6 mph).11 Transmission Neutralizer Lockout Switch. Rocker switch that locks out the neutralizer. Defaults back to neutralizer “on”upon machine start up.China's modern 20 wheel loaders began in the mid-1960s of the Z435. The aircraft as a whole rack, rear axle steering. After years of hard work, the attraction was the world's most advanced technology wheel loader on the basis of the successful development of the power of 162 KW of shovel-fit wheel loaders, stereotypes for Z450 (later ZL50), and in 1971 December 18, formally appraised byexperts. Thus the birth of China's first articulated wheel loader, thus creating our industry loader formation and development history.Z450-type loader with hydraulic mechanical transmission, power shift, Shuangqiaoshan drive, hydraulic manipulation, articulated power steering, gas oil Afterburner brake wheel loaders, and other modern, the basic structure of the world's advanced level for the time . Basically represent the first generation of wheeled loading the basic structure. The aircraft in the overall performance of dynamic, and insertion force a rise of power and flexibility, manipulation of light, the higher operating efficiency of a series of advantages.1978, Heavenly Creations by the Department in accordance with the requirements of machinery, worked out to LIUGONG Z450-based type of wheel loaders series of standards. The development of standards, with reservations Z representatives loaders, L replaced by "4" on behalf of wheel, for ZL50 to Z450, it is so developed a LIUGONG ZL50-based China ZL-wheel loaders series of standards, this is Wong loader on the development of China's a major turning point. The standard was worked out by the industry after the division of labor, LIUGONG Xiamen ZL40 the manufacture of the large and medium wheel loaders, as workers, to the following small and medium-sized manufacturing ZL30 wheel loaders, and gradually formed a LIUGONG Xiamen workers, and 10% for workers at the loader to four backbone enterprises. To the late 1970s, early 1980s loader manufacturing enterprises in China has increased to more than 20, China has initially formed the loader industry. So far, China has developed wheel loader to the third generation, but the basic structure is still the Z450 (ZL50) evolved from. Change is not a very large second generation, third generation of some larger changes. 2001 China loader industry-wide total sales have exceeded 30,000 Taiwan, the world loader in the forefront of the market. Therefore, at present, China has become the world's loader marketing power.Prospect of small loaderFor a long time, small loader always been neglected in the status of a government department, not to regulate the management of the industry, well-known businesses loader products is dismissive. However, these did not affect small loader (hereinafter referred to small equipment) rapid development, and now with a small market despite its huge market demand has attracted such as the Long renowned engineering machinery enterprises to participate in the competition, the main battlefield in the rural areas with the small size of the market, sales have already reached 4 ~ 5 million, more than 200 brands to participate in market competition. But small market can be said to be installed speed expansion disorderly competition coexist. How to achieve industrial upgrading is placed in front of the small equipment industry must resolve a problem.Lack industry attributionCompared with large and medium-sized industries loaders, small with the development of the industry can use "plan" to describe, not only government departments related to the absence of industrial policies or development plans, and to date, industry has not completely clear attribution, the reality of the small equipment industries across engineering machinery, agricultural machinery and construction machinery, the three industries of grey areas. Despite the small market with a flourishing, but all small equipment manufacturers and dealers can dodge exists in the industry before the many obstacles to development.Small installed mainly refers to the rated load between 0.3 ~ 0.9 T products, also known as micro-loader. As industry ownership is not clear, with small products has been no unified national technology and quality standards, the overwhelming majority of products are installed in the small-wheeled tractor developed on the basis of the. In addition small installed the product is currently used by the maincomponent parts from tractors and light truck, not by the needs of small equipment for low-speed heavy-duty bridge, special bins key component parts, including even small projects with special tires. As a low technical content, resulting in a very low threshold of industry and become the de facto "open" industry, any person, business can be very easily installed into small industries.Small enterprises have installed a number of "fans", according to Construction Machinery Association Scraper Branch Secretary-General Chen Kai Yun, a conservative estimate at more than 200. More concentrated in Shandong Laizhou, Taian, Weifang, in Luoyang, Henan Province, Quanzhou, Fujian Province, and other places, annual sales of more than 2,000 Taiwan enterprises with a small handful, the majority of small businesses with annual sales in 3200 by the following, with the production of small enterprises , the same easy to set up and close down.It is precisely because the strength of small enterprises with very limited products without high technology content, in the vast majority of enterprises to participate in market competition are in the process of basically a single means to price competition to sell products for the purpose, without taking into account future market things. In the common with the credit industry, services, brand competition means small industry basically not installed, in addition to differences in the strength of enterprises and product differentiation, marketing and management philosophy that is the deep-seated causes.Because users of the products of small equipment to mainly rural users, and users can only cover rural farm machinery sales networks, construction machinery and construction machinery sales are only part of the network coverage in rural areas. And the sale of equipment similar, with small products also requires agents or distributors can take the initiative to sell products to users and to users with standard and thoughtful service, and farm machinery dealers more customary sit shop operator, has no sales force, There is no specialized service teams, more difficult to expect the market planning, customer management. Construction machinery dealers and farm machinery dealers also have a lot of similarities, and engineering machinery dealers not accustomed to deal with rural users. Therefore, the small market is not mature with the sales network, to a large extent affected the market maturation process can not be achieved on the one hand, the user guide, on the other hand, can not be achieved on the manufacturers facilitating role. Operating environment and the use of the different habits, resulting in a lack of support for non-small pieces of installed products can hardly meet the actual needs of users, increasing the cost of services at the same time, improve customer satisfaction become almost impossible task.Increased market differentiationUnlike the preceding two years, with no small on the future of the market is basically no doubts. However, when the small rural installed by the new face of the building the vast potential market demand, whether it is the product itself, or the level of industrial development is clearly not satisfied. And because of the double impact of external factors, with small market differentiation is an inexorable trend. Relying solely on price competition means does not make the small favorably with industry development. In fact, it is due to excessive price competition, leading to small enterprises with low profitability, sales, and the prosperity of the entire industry can not hide the crisis of survival. Anticipate with a few small companies have started the "innovation" in the product upgrades at the same time, learn from the equipment industry and other related industries experience, to establish their own marketing team and distribution network and market competition tends to differentiation.In the high-end users with the needs of small change, directly contributing to small enterprises with the differentiation, with the concept of progress andconsumer financial strength of the expansion, some of the rural users (particularly in the industrialized operation of agriculture users) product performance and after-sales service and put forward higher requirements. Liaoning Anshan Haihong such as production of high-end products not only with small to have their own patented technology (use of mechanical devices greatly enhance the performance of its products, avoid using electric control, hydraulic devices, such as product performance after upgrading to the use of rural users increased maintenance costs ), and introduced the "non-controversial" services.Especially in big enterprises with increased involvement of small enterprises with pressure, the end of 2006, the Dragon Holdings acquired Henan Baiyun electrical and mechanical equipment involved in the production of small fields.Small with a huge potential market demand, but only to meet user needs, and guide the user needs, small equipment will have lasting vitality. Existing small enterprises with well-known loaders already facing small enterprises involved with the production sectors and small users to buy equipment or equipment, such as small excavators alternative products twin crises, with the production of small enterprises can take the initiative to upgrade their win more more time and greater market space.Any industries are indispensable for the development of market competition and government regulations two factors. With the status quo on small industries, market competition and excessive government regulation missing, the entire industry in a very low level of operation development, and a lack of development of the industry often staying power will gradually shrink, or even disappear.First to be addressed is the issue of trade with small, small equipment products really have their own products "definition", a special product standards. Although at this stage with small user groups mainly concentrated in the rural market, but the market coverage of the future is certainly both urban and rural areas, this is because small equipment can be widely used for municipal maintenance, landscape construction, building and construction, underground loading and unloading areas.Second, improve industry access threshold is a feasible solution. Small equipment industry can learn from the industry's largest equipment manufacturers licensing system, in terms of production quality suitable restrictions and improve the industry's manufacturing standards.In recent years loader well-known enterprises in recent years have involved with the production of small areas, such as the Dragon, XCMG, and the mountains, but not really most of the production of one ton of small equipment products, the main reason is hindering their high-end products in the market inadequate capacity. However, this also means that for the small enterprises with not too much time, if not in the relatively short period of time upgrading of enterprises and products, from business philosophy, product marketing idea to the concept of all-round self-improvement, self-transformed into a long-term development objectives and market competition-conscious modern manufacturing enterprises, and alarger-scale sales, in the future and well-known enterprises loader win in the competition may be very small.Mechanical Engineering Society of China was founded in 1936, China was set up earlier, the largest one of the Institute of Engineering. The existing 33 professional chapters, 180,000 members, of whom there are more than 3,000 senior members, more than 500 members of Hong Kong, Macao and overseas, there are more than 4,000 corporate members.Academic exchange is the Institute's basic functions, the Institute is held annually hundreds, and colorful academic conferences. Special is an annual Chinese Mechanical Engineering Society annual meeting, the topic is the integration。
毕业设计机电工程系中英文翻译对照
English translationThe E- Behind EverythingElectricity and magnetism run nearly everything we plug in or turn on. Although it’s something we take for granted, it has taken hundreds of years of experimentation and research to reach the point where we flick a switch and the lights go on.People knew about electricity for a long time. Ancient Greeks noticed that if they rubbed a piece of amber, feathers would stick to it. You’ve experienced a similar thing if you’ve ever had your hair stick up straight after you combed it, or had your socks stick together when you removed them from the drier. This is called static electricity, but back then nobody knew how to explain it or what to do with it.Experiments using friction to generate static electricity led to machines that could produce large amounts of static electricity on demand. In 1660 German Otto von made the first electrostatic generator with a ball of sulfur and some cloth. The ball symbolized the earth, and he believed that this little replica of the e arth would shed part of its electric “soul” when rubbed. It worked, and now scientists could study electric shocks and sparks whenever they wanted.As scientists continued to study electricity, they began thinking of it as an invisible fluid and tried to capture and store it. One of the first to do this was Pieter van, Holland. In 1746 he wrapped a water-filled jar with metal foil and discovered that this simple device could store the energy produced by an electrostatic generator. This device became known as the jar. were very important in other people’s experiments, such as Benjamin Franklin’s famous kite experiment. Many people suspected that lightning and static electricity were the same thing, since both crackled and produced bright sparks. In 1752 Franklin attached a key to a kite and flew it in a storm-threatened sky. (NOTE that Franklin did not fly a kite in an actual storm. NEVER do that!) When a thundercloud moved by, the key sparked. This spark charged the jars and proved that lightning was really electricity. Like many experimenters and scientists Franklin used one discovery to make another. Franklin was not the only scientist inspired to conduct experiments with electricity. In the 1780s, the Italian scientist Luigi m ade a dead frog’s leg move by means of an electric current. called this “animal electricity.” He thought that the wet animal tissue generated electricity when it came in contact with metal probes. He even suggested that the soul was actually Italian Alessandro Volta was skeptical of con clusions. In 1799 he discovered that it wasn’t animal tissue alone producing the electric current at all. Volta believed that the current was actually caused by the interaction of water and chemicals in the animal tissue with the metal probes. Volta stacked metal disks separated by layers of cardboard soaked in salt water. This so-called voltaic pile produced an electric current without needing to be charged like a jar. This invention is still around today, but we call it the battery.Volta’s pile was a lot different from the batteries you put in your Discman. It was big, ugly, and messy, but it worked, making Volta the first person to generate electricity with a chemical reaction. His work was so important that the term volt—the unit of electrical tension or pr—is named in his honor. As for Galvani, although he was proven wrong, his work stimulated research on electricity and the body. That research eventually proved that nerves do carry electrical impulses, an important medical discovery. Like electricity, magnetism was baffling to the earliest researchers. Today manufactured magnets are common, but in earlier timesthe only available magnets were rare and mysterious rocks with an unexplainable attraction for bits of iron. Explanations of the way they work sound strange today. For example, in the 1600, English doctor William Gilbert published a book on magnetism. He thought that these strange substances, called “lodestones,” had a soul that accounted for the attraction of a lodestone to iron and steel. The only real use for lodestones was to make compasses, and many thought the compass needle’s movement was in response to its attraction to the earth’s “soul.” By 1800, after many years of study, scientists began wondering if these two mysterious forces—electricity and magnetism—were related. In 1820 Danish physicist Hans Oersted showed that whenever an electric current flows through a wire, it produces a magnetic field around the wire. French mathematician André-Marie used algebra to come up with a mathematical formula to describe this relationship between electricity and magnetism. He was one of the first to develop measuring techniques for electricity. The unit for current, the ampere, abbreviated as amp or as A, is named in his honor. Groundbreaking experiments in electromagnetism were conducted by British scientist Michael Faraday. He showed that when you move a loop of a wire in a magnetic field, a little bit of current flows through the loop for just a moment. This is called induction. Faraday constructed a different version of it called the induction ring. In later years, engineers would use the principle of the induction ring to build electrical transformers, which are used today in thousands of electrical and electronic devices. Faraday also invented a machine that kept a loop of wire rotating near a magnet continuously. By touching two wires to the rotating loop, he could detect the small flow electric current. This machine used induction to produce a flow of current as long as it was in motion, and so it was an electromagnetic generator. However, the amount of electricity it produced was very tiny. There was still another use for induction. Faraday also created a tiny electric motor—too small to do the work of a steam engine but still quite promising. For thousands of years electricity and magnetism were subjects of interest only to experimenters and scientists. Nobody thought of a practical way of using electricity before the 1800s and it was of little interest to most people. But by Faraday’s time invento rs and engineers were gearing up to transform scientific concepts into practical machines.Telegraphs and TelephonesOne of the most important ways that electricity and magnetism have been put to use is making communication faster and easier. In this day o f instant messaging, cell phones, and pagers, it’s hard to imagine a time when messages had to be written and might spend weeks or even months reaching their destination. They had to be carried great distances by ships, wagon, or even by horseback—you coul dn’t just call somebody up to say hello. That all changed when inventors began using electricity and magnetism to find better ways for people to talk to each other. The telegraph was first conceived of in the 1700s, but few people pursued it. By the 1830s, however, advancements in the field of electromagnetism, such as those made by Alessandro Volta and Joseph Henry, created new interest in electromagnetic communication. In 1837, English scientist Charles Wheatstone opened the first com telegraph line between London and Camden Town, a distance of 1.5 miles. Building on, Samuel Morse, an American artist and inventor, designed a line to connect Washington, DC and Baltimore, Maryland in 1844. Morse’s telegraph was a simple device that used a battery, a switch, and a small electromagnet, but it allowed people miles apart to communicate instantly. Although Morse is often credited with inventing the telegraph, his greatest contribution was actually Morse, a special language designed for the telegraph. Morse'scommercialization of the telegraph spread the technology quickly. In 1861 California was connected to the rest of the United States with the first transcontinental telegraph line. Five years later, engineers found a way of spanning the Atlantic Ocean with telegraph lines, thus connecting the United States and Europe. This was an enormous and challenging job. To do it engineers had to use a huge ship called The Great Eastern to lay the cable across the ocean. It was the only ship with enough room to store all that cable. The world was connected by wire before the nation was connected by rail—the transcontinental railroad wasn’t completed until 1869! The telegraph was the key to fast, efficient railroad service. The railroads and the telegraph expanded side-by-side, crisscrossing every continent, except Anta, in the late 1800s. In the late 19th and early 20th centuries, telegraphy became a very lucrative business for companies such as Western Union. It also provided women with new career options. As convenient as the telegraph was, people dreamt of hearing the voices of loved ones who lived far away. Pretty soon, another instrument to communicate across distances was invented. Alexander Graham Bell, a teacher and inventor, worked with the deaf and became fascinated with studying sound. In 1875, Bell discovered a way to convert sound waves to an undulating current that could be carried along wires. This helped him invent the telephone. The first phone conversation was an inadvertent one between Bell and Watson, his ass istant in the next room. After spilling some acid, Bell said “Mr. Watson, come here.I want you.” He patented his device the same year. Early phone service wasn’t as portable and convenient as today’s. At first, telephones we connected in pairs. You could call only one person, and they could only call you. The telephone exchange changed all that. The first exchange was in New Haven, Connecticut in 1878. It allowed people who subscribed to it to call one another. Operators had to connect the calls, but in 1891 an automatic exchange was invented. Some problems had to be solved, though, before long-distance telephoning could work. The main one was that the signal weakened with distance, disappearing if the telephone lines were too long. A solution was found in 1912 with a way to amplify electrical signals, and transcontinental phone calls were possible. A test took place in 1914, and the next year, Bell, who was in New York, called Watson, who was in San Francisco. He said the same thing he had said during the first phone conversation. Watson’s answer? “It will take me five days to get there now!”Plc development1.1 MotivationProgrammable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLCs per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.Though PLCs are widely used in industrial practice, the programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicating [Moody and Morley, 1999, p. 110]:`If houses were built like software projects, a single woodpecker could destroy civilization.” Particularly, practical problems in PLC programming are to eliminate software bugs and to reduce the maintenance costs of old ladder logic programs. Though the hardware costs of PLCs are dropping continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLCs can be used.In general, the productivity in generating PLC is far behind compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC based software design because PLC-programming requires a simultaneous consideration of hardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than SO0/a of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs [Rockwell, 1999].In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects.1.2 Objective and Significance of the ThesisThe objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, that is, reducing programming and debugging time and their variation, increasing flexibility of the automation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developer.A systematic approach to designing PLC software can overcome deficiencies in the traditional way of programming manufacturing control systems, and can have wide ramifications in several industrial applications. Automation control systems are modeled by formal languages or, equivalently, by state machines. Formal representations provide a high-level description of the behavior of the system to be controlled. State machines can be analytically evaluated as to whether or not they meet the desired goals. Secondly, a state machine description provides a structured representation to convey the logical requirements and constraints such as detailed safety rules. Thirdly, well-defined control systems design outcomes are conducive to automatic code generation- An ability to produce control software executable on commercial distinct logic controllers can reduce programming lead-time and labor cost. In particular, the thesis is relevant with respect to the following aspects.Customer-Driven ManufacturingIn modern manufacturing, systems are characterized by product and process innovation, become customer-driven and thus have to respond quickly to changing system requirements. A majorchallenge is therefore to provide enabling technologies that can economically reconfigure automation control systems in response to changing needs and new opportunities. Design and operational knowledge can be reused in real-time, therefore, giving a significant competitive edge in industrial practice.Higher Degree of Design Automation and Software QualityStudies have shown that programming methodologies in automation systems have not been able to match rapid increase in use of computing resources. For instance, the programming of PLCs still relies on a conventional programming style with ladder logic diagrams. As a result, the delays and resources in programming are a major stumbling stone for the progress of manufacturing industry. Testing and debugging may consume over 50% of the manpower allocated for the PLC program design. Standards [IEC 60848, 1999; IEC-61131-3, 1993; IEC 61499, 1998; ISO 15745-1, 1999] have been formed to fix and disseminate state-of-the-art design methods, but they normally cannot participate in advancing the knowledge of efficient program and system design.A systematic approach will increase the level of design automation through reusing existing software components, and will provide methods to make large-scale system design manageable. Likewise, it will improve software quality and reliability and will be relevant to systems high security standards, especially those having hazardous impact on the environment such as airport control, and public railroads.System ComplexityThe software industry is regarded as a performance destructor and complexity generator. Steadily shrinking hardware prices spoils the need for software performance in terms of code optimization and efficiency. The result is that massive and less efficient software code on one hand outpaces the gains in hardware performance on the other hand. Secondly, software proliferates into complexity of unmanageable dimensions; software redesign and maintenance-essential in modern automation systems-becomes nearly impossible. Particularly, PLC programs have evolved from a couple lines of code 25 years ago to thousands of lines of code with a similar number of 1/O points. Increased safety, for instance new policies on fire protection, and the flexibility of modern automation systems add complexity to the program design process. Consequently, the life-cycle cost of software is a permanently growing fraction of the total cost. 80-90% of these costs are going into software maintenance, debugging, adaptation and expansion to meet changing needs [Simmons et al., 1998].Design Theory DevelopmentToday, the primary focus of most design research is based on mechanical or electrical products. One of the by-products of this proposed research is to enhance our fundamental understanding of design theory and methodology by extending it to the field of engineering systems design. A system design theory for large-scale and complex system is not yet fully developed. Particularly, the question of how to simplify a complicated or complex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outcomes of formal representations in computer sciences and operations research, such as discrete event system modeling, can advance future development in engineering design. Application in Logical Hardware DesignFrom a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely complex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into acomponent design and a system design stage. At component design stage, single functions are designed and verified. At system design stage, components are aggregated and the whole system behavior and functionality is tested through simulation. In general, a complete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware design.1.3 Structure of the ThesisFigure 1.1 illustrates the outline of the following thesis. Chapter 2 clarifies the major challenges and research issues, and discourses the relevant background and terminology. It will be argued that a systematic design of PLC software can contribute to higher flexibility and reconfigurability of manufacturing systems. The important issue of how to deal with complexity in engineering design with respect to designing and operating a system will be debated. The research approach applied in this thesis is introduced starting from a discussion of design theory and methodology and what can be learnt from that field.Chapter 3 covers the state-of-the-art of control technology and the current practice in designing and programming PLC software. The influences of electrical and software engineering are revealed as well as the potentially applicable methods from computer science are discussed. Pros and cons are evaluated and will lead to the conclusion that a new methodology is required that suffices the increasing complexity of PLC software design.Chapter 4 represents the main body of the thesis and captures the essential features of the design methodology. Though design theory is regarded as being in a pre- scientific stage it has advanced in mechanical, software and system engineering with respect to a number of proposed design models and their evaluation throughout real-world examples. Based on a literature review in Chapter 2 and 3 potential applicable design concepts and approaches are selected and applied to context of PLC software design. Axiomatic design is chosen as underlying design concept since it provides guidance for the designer without restriction to a particular design context. To advance the design concept to PLC software design, a formal notation based on statechart formalism is introduced. Furthermore, a design process is developed that arranges the activities needed in a sequential order and shows the related design outcomes.In Chapter 5, a number of case studies are given to demonstrate the applicability of the developed design methodology. The examples are derived from a complex reference system, a flexible assembly system. The achieved insights are evaluated in a concluding paragraph.Chapter 6 presents the developed computerized design tool for PLC software design on a conceptual level. The software is written in Visual Basic by using ActiveX controls to provide modularity and reuse in a web-based collaborative programming environment. Main components of the PLC software are modeling editors for the structural (modular) and the behavioral design, a layout specification interface and a simulation engine that can validate the developed model. Chapter 7 is concluding this thesis. It addresses the achievements with respect to the research objectives and questions. A critical evaluation is given alongside with an outlook for future research issues.电力的故事当我们插上电源,打开旋钮,电和磁差不多在每样东西上都运行着,今天我们知道这是什么,这一些花了人们上百年时间的实验和研究来达到这一点—当我们按下按钮时,光亮已经开始，人们对电的了解已经有很长一段时间了.古希腊人注意到,摩擦一块琥珀,羽毛将能被吸住.你已经经历过相类似的事情,当你梳头时,头发将垂直竖起,当你从干燥机中拿袜子时,袜子也会粘在一起.这被称作静电.但是在以前人们不知道如何解释此类现象或如何应用这种现象，使用摩擦产生的静电来带动机器的实验可以产生大量所需要的静电.在1660年,德国人Otto von Guericke用一个硫磺球和一些布制造了第一台静电发电机.硫磺球象征大地,他深信这种小型地球复制品被摩擦时将流出电的灵魂,他成功了,现在的科学家可以在任何想要的时候来研究电击和电火花.随着科学家们持续对电的研究,他们开始认为它以一种看不见的方式流动,并试图去捕获并储存.第一次去做这项研究的是荷兰Leyden的Pieter van Musschenbroek.1746,他用一个金属箔片包一个装满水的罐子,发现这种简单的设备能储存由静电发电机产生的能量.这个设备后来著名的莱顿瓶.莱顿瓶在其他人的实验中有非常重要的作用.如Benjamin Franklin著名的风筝实验.许多人认为闪电和静电是同一种东西,由于双方碰撞产生明亮的电火花.1752年, Franklin将一把钥匙绑在风筝上,在一个暴风即将来临的天气里放飞(请记住Franklin不是在一个真正的暴风寸中放飞的,永远不要这样做),当一块雷雨云经过时,钥匙被闪电击中,闪电充满莱顿瓶,由此证明闪电实际也是一种电力.同其他实验人和科学家一样, Franklin用一个发现来做另外一个. Franklin并不是唯一的在电力实验方面灵光突现的科学家.18世纪80年代,意大利的科学家Luigi Galvani用电流让一只切断的青蛙的腿移动. Galvani称之为生物电.他认为当潮湿的动物组织同金属探测针接触时产生电能.他甚至大胆预测精神也是一种电能。
本科毕业设计(论文)外文翻译译文
本科毕业设计（论文）外文翻译译文学生姓名：院（系）：油气资源学院专业班级：物探0502指导教师：完成日期：年月日地震驱动评价与发展：以玻利维亚冲积盆地的研究为例起止页码：1099——1108出版日期：NOVEMBER 2005THE LEADING EDGE出版单位：PanYAmericanYEnergyvBuenosYAiresvYArgentinaJPYBLANGYvYBPYExplorationvYHoustonvYUSAJ.C.YCORDOVAandYE.YMARTINEZvYChacoYS.A.vYSantaYCruzvYBolivia 通过整合多种地球物理地质技术，在玻利维亚冲积盆地，我们可以减少许多与白垩纪储集层勘探有关的地质技术风险。
通过对这些远景区进行成功钻探我们可以验证我们的解释。
这些方法包括盆地模拟，联井及地震叠前同时反演，岩石性质及地震属性解释，A VO/A V A,水平地震同相轴，光谱分解。
联合解释能够得到构造和沉积模式的微笑校正。
迄今为止，在新区有七口井已经进行了成功钻探。
基质和区域地质。
Tarija/Chaco盆地的subandean 褶皱和冲断带山麓的中部和南部，部分扩展到玻利维亚的Boomerange地区经历了集中的成功的开采。
许多深大的泥盆纪气田已经被发现，目前正在生产。
另外在山麓发现的规模较小较浅的天然气和凝析气田和大的油田进行价格竞争，如果他们能产出较快的油流而且成本低。
最近发现气田就是这种情况。
接下来，我们赋予Aguja的虚假名字就是为了讲述这些油田的成功例子。
图1 Aguja油田位于玻利维亚中部Chaco盆地的西北角。
基底构造图显示了Isarzama背斜的相对位置。
地层柱状图显示了主要的储集层和源岩。
该油田在Trija和冲积盆地附近的益背斜基底上，该背斜将油田和Ben i盆地分开（图1），圈闭类型是上盘背斜，它存在于连续冲断层上，Aguja有两个主要结构：Aguja中部和Aguja Norte,通过重要的转换压缩断层将较早开发的“Sur”油田分开Yantata Centro结构是一个三路闭合对低角度逆冲断层并伴随有小的摆幅。
毕业设计英文 翻译(原文)
编号：毕业设计(论文)外文翻译（原文）院（系）：桂林电子科技大学专业：电子信息工程学生姓名： xx学号： xxxxxxxxxxxxx 指导教师单位：桂林电子科技大学姓名： xxxx职称： xx2014年x月xx日Timing on and off power supplyusesThe switching power supply products are widely used in industrial automation and control, military equipment, scientific equipment, LED lighting, industrial equipment,communications equipment,electrical equipment,instrumentation, medical equipment, semiconductor cooling and heating, air purifiers, electronic refrigerator, LCD monitor, LED lighting, communications equipment, audio-visual products, security, computer chassis, digital products and equipment and other fields.IntroductionWith the rapid development of power electronics technology, power electronics equipment and people's work, the relationship of life become increasingly close, and electronic equipment without reliable power, into the 1980s, computer power and the full realization of the switching power supply, the first to complete the computer Power new generation to enter the switching power supply in the 1990s have entered into a variety of electronic, electrical devices, program-controlled switchboards, communications, electronic testing equipment power control equipment, power supply, etc. have been widely used in switching power supply, but also to promote the rapid development of the switching power supply technology .Switching power supply is the use of modern power electronics technology to control the ratio of the switching transistor to turn on and off to maintain a stable output voltage power supply, switching power supply is generally controlled by pulse width modulation (PWM) ICs and switching devices (MOSFET, BJT) composition. Switching power supply and linear power compared to both the cost and growth with the increase of output power, but the two different growth rates. A power point, linear power supply costs, but higher than the switching power supply. With the development of power electronics technology and innovation, making the switching power supply technology to continue to innovate, the turning points of this cost is increasingly move to the low output power side, the switching power supply provides a broad space for development.The direction of its development is the high-frequency switching power supply, high frequency switching power supply miniaturization, and switching power supply into a wider range of application areas, especially in high-tech fields, and promote the miniaturization of high-tech products, light of. In addition, the development and application of the switching power supply in terms of energy conservation, resource conservation and environmental protection are of great significance.classificationModern switching power supply, there are two: one is the DC switching power supply; the other is the AC switching power supply. Introduces only DC switching power supply and its function is poor power quality of the original eco-power (coarse) - such as mains power or battery power, converted to meet the equipment requirements of high-quality DC voltage (Varitronix) . The core of the DC switching power supply DC / DC converter. DC switching power supply classification is dependent on the classification of DC / DC converter. In other words, the classification of the classification of the DC switching power supply and DC/DC converter is the classification of essentially the same, the DC / DC converter is basically a classification of the DC switching power supply.DC /DC converter between the input and output electrical isolation can be divided into two categories: one is isolated called isolated DC/DC converter; the other is not isolated as non-isolated DC / DC converter.Isolated DC / DC converter can also be classified by the number of active power devices. The single tube of DC / DC converter Forward (Forward), Feedback (Feedback) two. The double-barreled double-barreled DC/ DC converter Forward (Double Transistor Forward Converter), twin-tube feedback (Double Transistor Feedback Converter), Push-Pull (Push the Pull Converter) and half-bridge (Half-Bridge Converter) four. Four DC / DC converter is the full-bridge DC / DC converter (Full-Bridge Converter).Non-isolated DC / DC converter, according to the number of active power devices can be divided into single-tube, double pipe, and four three categories. Single tube to a total of six of the DC / DC converter, step-down (Buck) DC / DC converter, step-up (Boost) DC / DC converters, DC / DC converter, boost buck (Buck Boost) device of Cuk the DC / DC converter, the Zeta DC / DC converter and SEPIC, the DC / DC converter. DC / DC converters, the Buck and Boost type DC / DC converter is the basic buck-boost of Cuk, Zeta, SEPIC, type DC / DC converter is derived from a single tube in this six. The twin-tube cascaded double-barreled boost (buck-boost) DC / DC converter DC / DC converter. Four DC / DC converter is used, the full-bridge DC / DC converter (Full-Bridge Converter).Isolated DC / DC converter input and output electrical isolation is usually transformer to achieve the function of the transformer has a transformer, so conducive to the expansion of the converter output range of applications, but also easy to achieve different voltage output , or a variety of the same voltage output.Power switch voltage and current rating, the converter's output power is usually proportional to the number of switch. The more the number of switch, the greater the output power of the DC / DC converter, four type than the two output power is twice as large,single-tube output power of only four 1/4.A combination of non-isolated converters and isolated converters can be a single converter does not have their own characteristics. Energy transmission points, one-way transmission and two-way transmission of two DC / DC converter. DC / DC converter with bi-directional transmission function, either side of the transmission power from the power of lateral load power from the load-lateral side of the transmission power.DC / DC converter can be divided into self-excited and separately controlled. With the positive feedback signal converter to switch to self-sustaining periodic switching converter, called self-excited converter, such as the the Luo Yeer (Royer,) converter is a typical push-pull self-oscillating converter. Controlled DC / DC converter switching device control signal is generated by specialized external control circuit.the switching power supply.People in the field of switching power supply technology side of the development of power electronic devices, while the development of the switching inverter technology, the two promote each other to promote the switching power supply annual growth rate of more than two digits toward the light, small, thin, low-noise, high reliability, the direction of development of anti-jamming. Switching power supply can be divided into AC / DC and DC / DC two categories, AC / AC DC / AC, such as inverters, DC / DC converter is now modular design technology and production processes at home and abroad have already matured and standardization, and has been recognized by the user, but AC / DC modular, its own characteristics make the modular process, encounter more complex technology and manufacturing process. Hereinafter to illustrate the structure and characteristics of the two types of switching power supply.Self-excited: no external signal source can be self-oscillation, completely self-excited to see it as feedback oscillation circuit of a transformer.Separate excitation: entirely dependent on external sustain oscillations, excited used widely in practical applications. According to the excitation signal structure classification; can be divided into pulse-width-modulated and pulse amplitude modulated two pulse width modulated control the width of the signal is frequency, pulse amplitude modulation control signal amplitude between the same effect are the oscillation frequency to maintain within a certain range to achieve the effect of voltage stability. The winding of the transformer can generally be divided into three types, one group is involved in the oscillation of the primary winding, a group of sustained oscillations in the feedback winding, there is a group of load winding. Such as Shanghai is used in household appliances art technological production of switching power supply, 220V AC bridge rectifier, changing to about 300V DC filter added tothe collector of the switch into the transformer for high frequency oscillation, the feedback winding feedback to the base to maintain the circuit oscillating load winding induction signal, the DC voltage by the rectifier, filter, regulator to provide power to the load. Load winding to provide power at the same time, take up the ability to voltage stability, the principle is the voltage output circuit connected to a voltage sampling device to monitor the output voltage changes, and timely feedback to the oscillator circuit to adjust the oscillation frequency, so as to achieve stable voltage purposes, in order to avoid the interference of the circuit, the feedback voltage back to the oscillator circuit with optocoupler isolation.technology developmentsThe high-frequency switching power supply is the direction of its development, high-frequency switching power supply miniaturization, and switching power supply into the broader field of application, especially in high-tech fields, and promote the development and advancement of the switching power supply, an annual more than two-digit growth rate toward the light, small, thin, low noise, high reliability, the direction of the anti-jamming. Switching power supply can be divided into AC / DC and DC / DC two categories, the DC / DC converter is now modular design technology and production processes at home and abroad have already matured and standardized, and has been recognized by the user, but modular AC / DC, because of its own characteristics makes the modular process, encounter more complex technology and manufacturing process. In addition, the development and application of the switching power supply in terms of energy conservation, resource conservation and environmental protection are of great significance.The switching power supply applications in power electronic devices as diodes, IGBT and MOSFET.SCR switching power supply input rectifier circuit and soft start circuit, a small amount of applications, the GTR drive difficult, low switching frequency, gradually replace the IGBT and MOSFET.Direction of development of the switching power supply is a high-frequency, high reliability, low power, low noise, jamming and modular. Small, thin, and the key technology is the high frequency switching power supply light, so foreign major switching power supply manufacturers have committed to synchronize the development of new intelligent components, in particular, is to improve the secondary rectifier loss, and the power of iron Oxygen materials to increase scientific and technological innovation in order to improve the magnetic properties of high frequency and large magnetic flux density (Bs), and capacitor miniaturization is a key technology. SMT technology allows the switching power supply has made considerable progress, the arrangement of the components in the circuit board on bothsides, to ensure that the light of the switching power supply, a small, thin. High-frequency switching power supply is bound to the traditional PWM switching technology innovation, realization of ZVS, ZCS soft-switching technology has become the mainstream technology of the switching power supply, and a substantial increase in the efficiency of the switching power supply. Indicators for high reliability, switching power supply manufacturers in the United States by reducing the operating current, reducing the junction temperature and other measures to reduce the stress of the device, greatly improve the reliability of products.Modularity is the overall trend of switching power supply, distributed power systems can be composed of modular power supply, can be designed to N +1 redundant power system, and the parallel capacity expansion. For this shortcoming of the switching power supply running noise, separate the pursuit of high frequency noise will also increase, while the use of part of the resonant converter circuit technology to achieve high frequency, in theory, but also reduce noise, but some The practical application of the resonant converter technology, there are still technical problems, it is still a lot of work in this field, so that the technology to be practical.Power electronics technology innovation, switching power supply industry has broad prospects for development. To accelerate the pace of development of the switching power supply industry in China, it must take the road of technological innovation, out of joint production and research development path with Chinese characteristics and contribute to the rapid development of China's national economy.Developments and trends of the switching power supply1955 U.S. Royer (Roger) invented the self-oscillating push-pull transistor single-transformer DC-DC converter is the beginning of the high-frequency conversion control circuit 1957 check race Jen, Sen, invented a self-oscillating push-pull dual transformers, 1964, U.S. scientists canceled frequency transformer in series the idea of switching power supply, the power supply to the size and weight of the decline in a fundamental way. 1969 increased due to the pressure of the high-power silicon transistor, diode reverse recovery time shortened and other components to improve, and finally made a 25-kHz switching power supply.At present, the switching power supply to the small, lightweight and high efficiency characteristics are widely used in a variety of computer-oriented terminal equipment, communications equipment, etc. Almost all electronic equipment is indispensable for a rapid development of today's electronic information industry power mode. Bipolar transistor made of 100kHz, 500kHz power MOS-FET made, though already the practical switching power supply is currently available on the market, but its frequency to be further improved. Toimprove the switching frequency, it is necessary to reduce the switching losses, and to reduce the switching losses, the need for high-speed switch components. However, the switching speed will be affected by the distribution of the charge stored in the inductance and capacitance, or diode circuit to produce a surge or noise. This will not only affect the surrounding electronic equipment, but also greatly reduce the reliability of the power supply itself. Which, in order to prevent the switching Kai - closed the voltage surge, RC or LC buffers can be used, and the current surge can be caused by the diode stored charge of amorphous and other core made of magnetic buffer . However, the high frequency more than 1MHz, the resonant circuit to make the switch on the voltage or current through the switch was a sine wave, which can reduce switching losses, but also to control the occurrence of surges. This switch is called the resonant switch. Of this switching power supply is active, you can, in theory, because in this way do not need to greatly improve the switching speed of the switching losses reduced to zero, and the noise is expected to become one of the high-frequency switching power supply The main ways. At present, many countries in the world are committed to several trillion Hz converter utility.the principle of IntroductionThe switching power supply of the process is quite easy to understand, linear power supplies, power transistors operating in the linear mode and linear power, the PWM switching power supply to the power transistor turns on and off state, in both states, on the power transistor V - security product is very small (conduction, low voltage, large current; shutdown, voltage, current) V oltammetric product / power device is power semiconductor devices on the loss.Compared with the linear power supply, the PWM switching power supply more efficient process is achieved by "chopping", that is cut into the amplitude of the input DC voltage equal to the input voltage amplitude of the pulse voltage. The pulse duty cycle is adjusted by the switching power supply controller. Once the input voltage is cut into the AC square wave, its amplitude through the transformer to raise or lower. Number of groups of output voltage can be increased by increasing the number of primary and secondary windings of the transformer. After the last AC waveform after the rectifier filter the DC output voltage.The main purpose of the controller is to maintain the stability of the output voltage, the course of their work is very similar to the linear form of the controller. That is the function blocks of the controller, the voltage reference and error amplifier can be designed the same as the linear regulator. Their difference lies in the error amplifier output (error voltage) in the drive before the power tube to go through a voltage / pulse-width conversion unit.Switching power supply There are two main ways of working: Forward transformand boost transformation. Although they are all part of the layout difference is small, but the course of their work vary greatly, have advantages in specific applications.the circuit schematicThe so-called switching power supply, as the name implies, is a door, a door power through a closed power to stop by, then what is the door, the switching power supply using SCR, some switch, these two component performance is similar, are relying on the base switch control pole (SCR), coupled with the pulse signal to complete the on and off, the pulse signal is half attentive to control the pole voltage increases, the switch or transistor conduction, the filter output voltage of 300V, 220V rectifier conduction, transmitted through the switching transformer secondary through the transformer to the voltage increase or decrease for each circuit work. Oscillation pulse of negative semi-attentive to the power regulator, base, or SCR control voltage lower than the original set voltage power regulator cut-off, 300V power is off, switch the transformer secondary no voltage, then each circuit The required operating voltage, depends on this secondary road rectifier filter capacitor discharge to maintain. Repeat the process until the next pulse cycle is a half weeks when the signal arrival. This switch transformer is called the high-frequency transformer, because the operating frequency is higher than the 50HZ low frequency. Then promote the pulse of the switch or SCR, which requires the oscillator circuit, we know, the transistor has a characteristic, is the base-emitter voltage is 0.65-0.7V is the zoom state, 0.7V These are the saturated hydraulic conductivity state-0.1V-0.3V in the oscillatory state, then the operating point after a good tune, to rely on the deep negative feedback to generate a negative pressure, so that the oscillating tube onset, the frequency of the oscillating tube capacitor charging and discharging of the length of time from the base to determine the oscillation frequency of the output pulse amplitude, and vice versa on the small, which determines the size of the output voltage of the power regulator. Transformer secondary output voltage regulator, usually switching transformer, single around a set of coils, the voltage at its upper end, as the reference voltage after the rectifier filter, then through the optocoupler, this benchmark voltage return to the base of the oscillating tube pole to adjust the level of the oscillation frequency, if the transformer secondary voltage is increased, the sampling coil output voltage increases, the positive feedback voltage obtained through the optocoupler is also increased, this voltage is applied oscillating tube base, so that oscillation frequency is reduced, played a stable secondary output voltage stability, too small do not have to go into detail, nor it is necessary to understand the fine, such a high-power voltage transformer by switching transmission, separated and after the class returned by sampling the voltage from the opto-coupler pass separated after class, so before the mains voltage, and after the classseparation, which is called cold plate, it is safe, transformers before power is independent, which is called switching power supply.the DC / DC conversionDC / DC converter is a fixed DC voltage transformation into a variable DC voltage, also known as the DC chopper. There are two ways of working chopper, one Ts constant pulse width modulation mode, change the ton (General), the second is the frequency modulation, the same ton to change the Ts, (easy to produce interference). Circuit by the following categories:Buck circuit - the step-down chopper, the average output voltage U0 is less than the input voltage Ui, the same polarity.Boost Circuit - step-up chopper, the average output voltage switching power supply schematic U0 is greater than the input voltage Ui, the same polarity.Buck-Boost circuit - buck or boost chopper, the output average voltage U0 is greater than or less than the input voltage Ui, the opposite polarity, the inductance transmission.Cuk circuit - a buck or boost chopper, the output average voltage U0 is greater than or less than the input voltage Ui, the opposite polarity, capacitance transmission.The above-mentioned non-isolated circuit, the isolation circuit forward circuits, feedback circuit, the half-bridge circuit, the full bridge circuit, push-pull circuit. Today's soft-switching technology makes a qualitative leap in the DC / DC the U.S. VICOR company design and manufacture a variety of ECI soft-switching DC / DC converter, the maximum output power 300W, 600W, 800W, etc., the corresponding power density (6.2 , 10,17) W/cm3 efficiency (80-90)%. A the Japanese Nemic Lambda latest using soft-switching technology, high frequency switching power supply module RM Series, its switching frequency (200 to 300) kHz, power density has reached 27W/cm3 with synchronous rectifier (MOSFETs instead of Schottky diodes ), so that the whole circuit efficiency by up to 90%.AC / DC conversionAC / DC conversion will transform AC to DC, the power flow can be bi-directional power flow by the power flow to load known as the "rectification", referred to as "active inverter power flow returned by the load power. AC / DC converter input 50/60Hz AC due must be rectified, filtered, so the volume is relatively large filter capacitor is essential, while experiencing safety standards (such as UL, CCEE, etc.) and EMC Directive restrictions (such as IEC, FCC, CSA) in the AC input side must be added to the EMC filter and use meets the safety standards of the components, thus limiting the miniaturization of the volume of AC / DC power, In addition, due to internal frequency, high voltage, current switching, making the problem difficult to solve EMC also high demands on the internal high-density mountingcircuit design, for the same reason, the high voltage, high current switch makes power supply loss increases, limiting the AC / DC converter modular process, and therefore must be used to power system optimal design method to make it work efficiency to reach a certain level of satisfaction.AC / DC conversion circuit wiring can be divided into half-wave circuit, full-wave circuit. Press the power phase can be divided into single-phase three-phase, multiphase. Can be divided into a quadrant, two quadrant, three quadrants, four-quadrant circuit work quadrant.he selection of the switching power supplySwitching power supply input on the anti-jamming performance, compared to its circuit structure characteristics (multi-level series), the input disturbances, such as surge voltage is difficult to pass on the stability of the output voltage of the technical indicators and linear power have greater advantages, the output voltage stability up to (0.5)%. Switching power supply module as an integrated power electronic devices should be selected。
毕业设计的英文翻译----开放式控制器体系结构 - 过去,现在和未来
Open Controller Architecture - Past, Present and FutureGunter Pritschow (Co-ordinator), Yusuf Altintas, Francesco Jovane, Yoram Koren, Mamoru Mitsuishi, Shozo Takata, Hendrik van Brussel, Manfred Weck, Kazuo YamazakiAbstractOpen Control Systems are the key enabler for the realization of modular and re-configurable manufacturing systems. The large number of special purpose machines and the high level of automation have led to an increasing importance of open control systems based on vendor neutral standards. This paper gives an overview on the past, present and future of Open Controller Architecture. After reflecting on the different criteria, categories and characteristics of open controllers in general, the CNC products in the market are evaluated and an overview on the world-wide research activities in Europe, North America and Japan is given. Subsequently the efforts to harmonize the different results are described in order to establish a common world-wide standard in the future. Due to the “mix-and-match’’ nature of open controllers concentrated attention must be paid to testing mechanisms in the form of conformance and interoperability tests.Keywords: Open architecture control, CNC, Machine tool1 INTRODUCTIONOpen Architecture Control (OAC) is a well known term in the field of machine control. Since the early nineties several initiatives world-wide have worked on concepts for enabling control vendors, machine tool builders and end-users to benefit more from flexible and agile production facilities. The main aim was the easy implementation and integration of customer-specific controls by means of open interfaces and configuration methods in a vendor-neutral, standardized environment [13][19].The availability and broad acceptance of such systems result in reduced costs and increased flexibility. Software can be reused and user-specific algorithms or applications can be integrated. Users can design their controls according to a given configuration. This trend was forced both by the increasing number of special purpose machines with a high level of automation and the increasing development costs for software (Figure 1).Figure 1: CNC Hardware and software -Actual trend existingIn the past the CNC market was dominated by heterogeneous, device-oriented systems with proprietary hardware and software components. The tight coupling of application software, system software and hardware led to very complex and inflexible systems. Great efforts were made to maintain and further develop the products according to new market requirements. Modern CNC approaches, which comprise extensive functionality to achieve a high quality and flexibility of machining results combined with a reduced processing time, favor PC- based solutions with a homogenous, standardized environment (Figure 2). The structure is software- oriented and configurable due to defined interfaces and software platforms. Open control interfaces are necessary for continuously integrating new advanced functionality into control systems and are important for creating re-configurable manufacturing units [17]. Unbundling hardware and software allows profiting from the short innovation cycles of the semiconductor industry and information technology. With the possibility for reusing software components, the performance of the overall system increases simply by upgrading the hardware platform.Figure 2: PC-based, software-oriented Control SystemsThere are a lot of benefits for suppliers and users of open control systems (Figure 3) [7]. CNC designers and academics benefit from a high degree of openness coveringalso the internal interfaces of the CNC. For CNC users the external openness is much more important. It provides the methods and utilities for integrating user-specific applications into existing controls and for adapting to user-specific requirements, e.g. adaptable user interfaces or collection of machine and production data. The external openness is mainly based on the internal openness but has functional or performance Iimitations .2 STATE OF THE ART2.1 Control Systems and their interfacesControls are highly sophisticated systems due to very strict requirements regarding real-time and reliability. For controlling the complexity of these systems hardware and software interfaces are an essential means. The interfaces of control systems can be divided into two groups-external and internal interfaces (Figure4).External InterfacesThese interfaces connect the control system to superior units, to subordinate units and to the user. They can be divided into programming interfaces and communication interfaces. NC and PLC programming interfaces are harmonized by national or international standards, such as RS-274, DIN 66025 or IEC 61131-3. Communication interfaces are also strongly influenced by standards. Fieldbus systems like SERCOS, Profibus or DeviceNet are used as the interface to drives and 110s. LAN (Local Area Network) networks mainly based on Ethernet and TCP/lP do reflect the interfaces to superior systems.Internal InterfacesInternal interfaces are used for interaction and data- exchange between components that build up the control- system core. An important criterion in this area is the support of real-time mechanisms. To achieve a re-configurable and adaptable control the internal architecture of the control system is based on a platform concept. The main aims are to hide the hardware-specific details from the software components and to establish a defined but flexible way of communication between the software components. An application programming interface(API) ensures these requirements. The whole functionality of a control system is subdivided into several encapsulated, modular software components interacting via the defined API.2.2 Hardware and software structure of control systemsFigure 5 shows different variants for the hardware structures of control systems. Variant a) shows an analog drives interface with position controller in the control system core. Each module of this structure uses its own processor which leads to a large variety of vendor-specific hardware. Combining modules leads to a significant reduction of the number of processors. Variant b) shows intelligent digital drives with integrated control functionality, which result from higher capacity, miniaturization and higher performance of the processors. Variant c) shows a PC-based single processor solution with a real-time extension of the operating system. All control-functions run as software tasks in the PC-based real-time environment.2.3 Market overviewThe controls available in the market provide different levels of openness according to the criteria shown in Figure 6. An important criterion is the use of a standardized computing platform (i.e. hardware, operating system and middleware) as an environment to execute the HMI and CNC software. Besides this, the connectivity of the CNC to upper and lower factory levels must be guaranteed. Application Programming Interfaces (API) are used to integrate third party software in the CNC products. Al though most of today’s controls offer openness concerning the operator-related control functions (Human-Machine Interface, HMI) only few controls allow users to modify their low-level control algorithms to influence the machine-related control functions.Figure 7 gives an overview of the characteristics of today’s control s ystems regarding the degree of openness.Although many control systems provide open interfaces for software integration (e.g. OPC) there is still no common definition of data which is passed back and forth via the programming interface. Therefore, the control systems available on the market today do not implicitly support “plug-and-play” features. To improve this situation, the fieldbus systems can serve as a role model (see Figure 8). The variety of different fieldbus systems has led to the broad consensus that harmonizing the application-oriented interfaces is desirable in order to hide the plurality and the complexity of the systems from the user. Most fieldbus organizations are already using so-called device profiles in order to support the interchangeability of the devices of different vendors.For example, the SERCOS interface standard (IEC61491) for the cyclic and deterministic communication between CNC and drives has defined the semantics forapprox. 400 parameters describing drive and control functions which are used by the devices of different vendors.3 DEFINITIONS AND CATEGORIES OF OPENNESS3.1 DefinitionsThe “Technical Committee of Open Systems” of IEEE defines an open system as follows: “An open system provides capabilities that enable properly implemented applications to run on a variety of platforms from multiple vendors, interoperate with other system applications and present a consistent style of interaction with the user” (IEEE 1003.0).To estimate the openness of a controller the following criteria can be applied (Figure 9):Portability. Application modules (AM) can be used on different platforms without any changes, while maintaining their capabilities.Extendibility. A varying number of AM can run on a platform without any conflicts.Inferoperability. AM work together in a consistent manner and can interchange data in a defined way.Scalability. Depending on the requirements of the user, functionality of the AM and performance and size of the hardware can be adapted.To fulfill the requirements of the IEEE-definition and these criteria of openness, an open control system must be:vendor neutral. This guarantees independence of single proprietary interests.consensus-driven. It is controlled by a group of vendors and users (usually in the form of a user group or an interested group).standards-based. This ensures a wide distribution in the form of standards (national/international standards or de-facto standards).freely available. It is free of charge to any interested party.3.2 Categories of Open Control SystemsIf we speak of openness in control systems, the following categories can be identified (Figure 10):Open HMl: The openness is restricted to the non-real-time part of the control system. Adaptations can be made in user oriented applications.Kernel with restricted openness: The control kernel has a fixed topology, but offers interfaces to insert user-specific filters even for real-time functions.Open Control System: The topology of the control kernel depends on the process. It offers interchangeability, scalability, portability and interoperability.Open control systems that are available today mostly offer the possibility for modifications in the non-real-time part in a fixed software topology. They lack the necessary flexibility and are not based on vendor-neutral standards.3.3 RequirementsA vendor-neutral open control system can only be realized if the control functionality is subdivided in functional units and if well-defined interfaces between these units are specified (Figure 11). Therefore modularity can be identified as the key for an open system architecture. In determining the module complexity there is an obvious trade-off between the degree of openness and the cost of integration [6]. Smaller modules provide a higher level of openness and more options, but increase the complexity and integration costs. Furthermore such a low level of granularity can lead to much higher demands for resources and it may even deteriorate the real-time performance of the overall system.Combining modules in the manner of “mix-and-match’’ requires a comprehensive set of standard Application Programming Interfaces (APIs). For vendor-neutral open control systems the interfaces need to be standardized and broadly accepted. Due to the complexity of such modular systems the definition of a system architecture is recommendable and helpful. This leads to the introduction of so-called system platforms (Figure 12). These platforms encapsulate the specifics of a computing system by absorbing the characteristics of hardware, operating system and communication. The availability of such middleware systems facilitates the easy porting of application software and also the interoperability of application modules even in distributed heterogeneous environments.Due to the possibility to “mix-and-match’’ modules via standardized interfaces the quality of the overall system is determined by the degree of the interoperability between the single modules (see Section 5).4 SYSTEMS ON THE WAY TO THE MARKET4.1 Major international activitiesOSEC (Japan)The OSE (Open System Environment for Manufacturing) consortium was established in December 1994. Three project phases were carried out until March 1999 [1][2][3]. The OSEC Architecture was intended to provide end users, machine makers, control vendors, software vendors, system integrators, etc. a standard platform for industrial machine controllers, with which they can add their own unique values to the industrial machines, and hence promote the technical and commercial development of the industrial machines. The OSEC API is defined in the form of an interface protocol, which is used to exchange messages among controller software components representing the functionality and the real- time cycle. Each functional block can be encapsulated as an object so it is not necessary to deal with how a functional block processes messages to it at architecture level (Figure 13). Although the structure of functional blocks can be defined uniquely by the OSEC architecture from a logical point of view, the system is neither determined nor limited at its implementation phase because there are so many options for implementations. These options may include system contrivances such as device driver, interprocess communication, installation mechanisms such as static library and DLL, hardware factors like selection of controller card, and implementations of software modules added for execution control and/or monitoring of various software. In other words, the implementation model to realize the architecture model is not limited to a particular model. In this way, it is assured to incorporate various ideas in the implementation model depending on the system size or its hardware implementation and/or utilization.JOP (Japan)In parallel to the OSE consortium activities, MSTC formed the Open-Controller Technical Committee (OC- TC) from 1996 to 2000, under the umbrella of JOP (Japanese Open Promotion Group). The objectives of OC-TC were to provide the opportunities for various companies to discuss and work together on the standardization of open controller technologies. The OC- TC was also expected to act as liaison between domestic and international activities in this field. OC-TC was participated by approximately 50 members, which included major Japanese controller vendors, machine tool builders, integrators, users, and academics. Some of the members represented the other groups concerning open controllers such as the OSE consortium and the FA Intranet Promotion Group .One of the working groups was engaged in developing a standard API for interfacing between NC and PC-based HMI. It should be also effective for the communication between NC and an upper level management controller. The work was carried out based on the proposals from the major controller vendors and that from the OSE consortium. The developed specifications were named PAPI and released July, 1999 [4] [5]. PAPI was approved as a JIS (Japan Industrial Standard) technical report and published in October, 2000. To demonstrate the effectiveness of the specifications developed by OC-TC, in Nagoya in October 1999, two CNCs manufactured by different vendors were connected to a Windows NT machine in which the same HMI systems developed by the University of Tokyo were implemented (Figure 14). Since any specific controller architecture is not assumed, PAPI can be implemented in various types of existing CNC systems, such as PC + proprietary NC, PC + NC board, and Software NC on PC+110 board. The HMI system communicates with the CNCs via PAPI which is a function-oriented software library in the programming language C. The PAPI interface is neutralizing the vendor-specific interface by mapping the PAPI calls to the vendor-specific API and protocol.OMAC (USA)The Open Modular Architecture Controllers (OMAC) Users Group is an industry forum to advance the state of controller technology [l0]. An effort was undertaken within OMAC to define API specification for eventual submittal to an established standards body. The OMAC API adopted a component-based approach to achieve plug-and-play modularization, using interface classes to specify the API [11]. For distributed communication, component-based technology uses proxy agents to handle method invocations that cross process boundaries. OMAC API contains diffe rent “sizes” and “types” of reusab le plug-and-play components - component, module, and task - each with a unique Finite State Machine (FSM) model so that component collaboration is performed in a known manner. The term component applies to reusable pieces of software that serves as a building block within an application while the term module refers to a container of components. Tasks are components used to encapsulate programmable functional behavior consisting of a series of steps that run to completion, including support for starting, stopping, restarting, halting, and resuming, and may be run multiple times while a controller is running. Tasks can be used to build controller programs consisting of a series of Transient Tasks, with ability to restart and navigate, or as standalone Resident Tasks to handle specialized controller requirements, (e.g., axis homing or ESTOP).To integrate components, a framework is necessary to formalize the collaborations and other life cycle aspects in which components operate. The OMAC API uses Microsoft Component Object Model (COM) as the initial framework in which to develop components, with the expected benefit that control vendors could then concentrate on application-specific improvements that define their strategic market-share - as opposed to spending valuable programming resources reinventing and maintaining software “plumbing.”The primary problem with COM framework, specifically under the Windows 2000 operating system, is the lack of hard, real-time preemptive scheduling, but third party extensions to Windows 2000 can be used to overcome this requirement.Figure 15 illustrates a sketch of OMAC API controller functionality. The HMI module is responsible for human interaction with a controller including presenting data, handing commands, and monitoring events and in the OMAC API “mirrors” the actual controller with references to all the major modules and components via proxy agents. The Task Coordinator module is responsible for sequencing operations and coordinating the various modules in the system based on programmable Tasks. The Task Coordinator can be considered the highest level Finite State Machine in the controller. A Task Generator module translates an application-specific control program (e.g., RS 274 part program) into a series of application-neutral Transient Tasks. The Axis Group module is responsible for coordinating the motions of individual axes, transforming an incoming motion segment specification into a sequence of equi-time- spaced setpoints for the coordinated axes. The Axis module is responsible for servo control of axis motion, transforming incoming motion setpoints into setpoints for the corresponding actuators 10 points. The Control Law component is responsible for servo control loop calculations to reach specified setpoints. OSACA (Europe)In Europe the ESPRIT project OSACA (Open System Architecture for Controls within Automation Systems) was initiated in 1992 with the aim to unite European interests and to create a vendor-neutral standard for open control systems[9][16].It was supported by major European control vendor and machine tool builders. OSACA reached a mature state already in April 1996 having at its disposal a stable set of specifications and a tested pool for system software. Based on these results, several application-oriented projects were carried out. In 1988 two pilot demonstrators in the automotive industry proved the interoperability of OSACA-compliant controllers and applications. The OSACA association eth currently 35 members from all over the word is the lasting organization to keep and maintain the OSACA-related specifications.The basic technical approach of the OSACA architecture is the hierarchical decomposition of control functionality into so-called functional units (Figure 16).For each of these functional units (e.g. motion control, motion control manager, axescontrol, logic control, etc.) the interfaces are specified by applying object-oriented information models. This technique is similar to the approach of MAP/MMS but with a limited and manageable number of object classes.The data interface consists of several variable objects that support the read and/or write access to data structure(data flow).The data can be of a simple type or of a complex type(array, structure, union).By using formal templates(Figure17) all the characteristics of a single interface object are specified. These elements cover the name (e.g, “mc-active-feed-override”), the type (e.g. UNS32: 32-bit unsigned value), the scaling (e.g. 0.l%),the range and the access rights (read only, to all the major modules and components via proxy write only, read/write) of the data. An additional description is to avoid misinterpretations of the use of the data. The process interface consists of several process objects that are used to describe the dynamic behavior (control flow) of the application modules by means of finite state machine (FSM). The state machines are described by static states, dynamic states and transitions to change the states of a given state-machine. The transitions can handle input and output parameters to pass data between application modules via the communication platform. The formal template for such process interfaces consists of an unambiguous description and the following attributes: list of static states (identifier, list of possible transitions), list of dynamic states (identifier) and a list of transitions (input parameters, output parameters, return codes). The process interface can also be used to activate application-specific functions in form of procedure calls. The interoperability of distributed application modules is supported by an infrastructure (so-called OSACA platform) which comprises client-server principles, synchronous and asynchronous calls and event handling via any underlying communication protocol and media (e.g. by using the TCP/lP protocol). A dedicated configuration runtime system is handling the system’s startup and shutdown. Besides, it also allows an easy reconfiguration of the system.开放式控制器体系结构- 过去，现在和未来摘要开放式控制系统是用于模块化和可重新配置制造系统实现的关键推动者。
毕业设计英文翻译
沈阳工业大学化工装备学院毕业设计（论文）外文翻译毕业设计（论文）题目：含硫氨污水冷却器外文题目：Head processing technology译文题目：封头加工工艺院（系）：化工装备学院专业班级：过控0802班学生姓名：孙鹏博指导教师：闫小波2012年3月11日Head processing technology1.welding process1.1welding operationOur factory common welding methods are: manual welding, argon arc welding, submerged arc welding.(1) manual welding is mainly used for carbon steel 3-6mm plate welding.(2) submerged arc welding to more than 8mm carbon steel stainless steel sheet welding mainly.(3)3-6mm stainless steel argon arc welding with welding mainly. Commonly used stainless steel wire ER304and ER316L steel wire, commonly used to J422and J507and J426and J427low-temperature welding consumables. Flux of carbon steel used is the HJ431, stainless steel commonly used is HJ260,.As a result of welding wire flux can be easily affected with damp, stored in the infrared drying machine, flux HJ431and HJ260drying temperature is 250-300℃. Welding wire J422and J350drying temperature were 150℃ and 300 ℃Welding process is completely in accordance with the" welding" execution, sheet thickness determines the welding to welding or double sided arc welding in welding, after the weld seam inspection ( RT X ray ) judgment without pores, cracks and other defects, such as found in the above deficiencies, to the repair, until the filming.1.2 welding operation standard(1) welding procedure card after receiving process, affirm the process card and physical material, quantity, unit number, specifications, size instruction number is consistent, whether there is debris around the wafer, wafer splashes whether clean removal, such as treatment is not clean, will use the grinding clean.(2) there is no welding test plate, groove cutting quality can meet the requirement, material surface without obvious defects, such as abnormal response.(3) according to the" Regulations" welding procedure card check of welding groove type and dimensions correspond to.(4) on each side of groove surface grinding, butt edge offset is not greater than the10% thickness, and not more than1.5mm.(5) point fixed the first weld layer terminal welding length not less than 50mm, arc board specifications should be 150*150mm and a mask having R arc, team rounds should be given within 8 hours of welding, or to use flame to the moisture inside the baking groove.(6) the welder holds" welding" and" welding records" for welding consumables, welding two class library for registration, using flux field volume should not exceed 4 hours, or to continue to back into the oven drying.(7) a, preheating plate thickness not less than 30mm carbon steel, low alloy steel, the preheating temperature of welding process by" card"," standard" provisions of the welding technology.B, preheating range width not less than 4mm and no less than 100mm. C, in the process of welding groove at any time temperature shall not be less than the prescribed temperature.D, when welding temperature is below 0 ℃( arbitrary thickness) must be heated to 15 ℃or above in order to welding.(8) a before welding, welding to welding equipment inspection, examination was normal before welding facilities.According to B,"" the requirements of welding process welding, welding and fill in the recordsC, welding, welding layers shall be in accordance with" welding" requirements, welding shall not be a large current, less layers. (9) removal of the root a, stainless steel cleaning before the root groove sides, within the range of 300mm, splashing paint coating.B, using carbon arc air gouging, should be selected according to the request carbon rod diameter.C, root cleaning, grinding cleaning groove and two side the existence of carburized layer, oxide, slag and other sundries. Grinding width: manual welding, rust, oxide above 20mm, oil30mm above, automatic welding, rust, grease, oxides 25mm50mm groove inner grinding requirements, carbon steel, low alloy steelδn ≤10mm weld, its two ends within the range of 300mm carburized layer must be completely removed, the rest part allows the removal of more than 50%. Other non-ferrous metals must be completely clear. [3]D, root cleaning, composite steel Cr-Mo, manual welding and the thicknessofδn ≥30mm welds shall be examined by PT.(10) during the process of welding defect repair by welding repair welding repair monitor instruction experienced welders as. Repair welding process should eliminate soldering phenomenon, or polished after welding, the following defects must be removed before welding to welding crack,①partial②③pits the stomaA shall not be lower than the parent material, weld.B, there shall be no undercutting.C, without removing the residual high seam. The surface shall not have cracks, pores, crater, undercut and slag inclusions, and may not retain the slag and spatter.D, removal of residual high weld inspection shall not have any defect display PT.E, such as the defects of carbon steel, low-alloy steel repair procedures: a grinding wheel or a carbon arc gouging polishing cleaning→ PT check grinder grinding out the welding groove, welding, PT, stainless steel repair procedures: a grinding wheel or a carbon arc gouging polishing cleaning→PT (δ n≥ 2mm need )→grinder polished to a welding groove welding→ PT examination. [4](12) welded internal rework, repair procedures: location of defect, defect removal→ PT→→removal check welding weld→ PT examination. [5] (13) according to RT film, RT staff and the welders in welding seam together determine the location of defects, including the following requirements when using UT to determine the defect position, the first repairδ n≥ 30mm use UT to determine the location of defects, two or three repairδ n≥ 20mm using UT to determine the defect position, UT positioning by RT after class. The position and depth of defect ( calibration side shall be the depth of defect≤1/2 side).(14) after the welding inspector or monitor by confirmed, in the process card signed your name and object together with transfer to the next process, by the next process responsibility recognition can.2.stamping process2.1stamping operationStamping operation is small head forming an important operation. The same stamping is also head of the cracking, thinning appeared most processsection.2.2punching machine.(1) the master cylinder is mainly used to connect the die head, is the head forming the necessary parts.(2) side cylinder used for pressing die ring, fixing the upper and lower mold ring of head disk. The head in the pressing process is to prevent the crease, as an important part of the drum kit.(3) the overflow valve used for controlling the compressor overall pressure, prevent the wafer during the pressing process of tears. (4) stamping valve in pressure, stamping valve on pressure relief, achieve average pressure effect.In addition, circuit boards, motors, circuit boards, storage tank, operation platform, pedestal are stamping machine components.2.3.3 stamping operation steps(1) first of all to undertake a blanking process card, find a good wafer.(2) the control process card on the technological requirements, put ona set of corresponding die, and with the use of gauges to determine the selected die size and to suppress the wafer size.(3) the wafer is clamped on the upper and lower mold inside the circle, and determine the die head of the center point and the center point of the wafer in a straight line.(4) the operation ring mold and die relative motion, pressure test, according to the control rod rebound to judge the size of the pressure, thereby regulating pressure size.(5) pressure test end, pressed wafer, stamping.2.3the stamping operation standard(1) the control task orders, confirm physical and process card is consistent, according to the process card confirming workpiece number, material, specification, batch number and other factors, at the same time check wafer end there is no crack, burr, polished wafer whether it meets the requirements, whether chamfer, is facing the good, there are special requirements when the problem is found, in time to contact.(2) according to the process card correct selection of die mold surface, inspection, found bruises and serious injury must be polished, but must be clean mold surface corrosion and dirt.(3) according to the technology card size, shape, texture, straight edge higher to suppress.(4) the warm-stamping ( according to requirement sheet property is heated to a certain temperature, and then stamping process ), to prepare a baking gun, gas, oxygen, percussion with head shall prepare the corresponding template, double-sided film to the wafer edge of both sides in a range of about 200-300mm template removal, and clear the film surface. [6] (5) mounted on the lower die, as the case to join the die pad, the wafer inside and outside surface coated with oil, applied range of top to200-300mm, smear should be uniform, the upper and lower mold are evenly coated.(6) the first gold stamping head, hanging out with a model head, check section shape, at the same time, check whether the drum kit, and there is no thinning, and check the surface has no scratch, hoop printing, such as none of the above abnormalities can continue to stamping, head forming, sealing surfaces such as scratches are timely grinding, and confirm the minimum board thickness, confirm whether a scratch, strain, curved peel, orange peel, drum kits, wrinkle, hoop printing etc..(7) such as a head drum kit fold phenomenon should be together with the card with the move to rework process technology.(8) each head should be able to see the instruction, piece number, material, or to transplantation, each product specifications after testing, the process card ( to sign the name ) together to the next process, by the next process validation.3.pressure drum process3.1pressure drum operationPressure drum process and stamping processes are the same steps in the process, stamping process range of φ 159- φ1900mm and pressure drum process is in the range of φ 1600- φ4800mm. And stamping is different pressure drum mostly the head generally forming, eventually forming is completed by spinning, stamping without the special requirements of customers, eventually forming step is not required. φ 1600- φ1900mm heads the two processes is needed.3.2pressure drum machine.(1) the main cylinder is provided with an upper die head is pressed drumexecution as long as part of.(2) supporting seat fixed lower die and upper die head center in a straight line.(3) supporting frame1is provided with a rolling wheel, a position adjusting before and after.(4) supporting frame is provided with a rolling wheel rotating disk II. In addition, there are hydraulic system, the motor, oil pump, oil tank, and a control console.3.3pressure drum machine operation steps(1) first of all to undertake a blanking process card, find a good wafer.(2) the control process card on the technological requirements, put ona set of corresponding die, and with the use of gauges to determine the selected die size and to suppress the wafer size.(3) and stamping machine is different from the original film is not pressure drum center began to suppress, but from the wafer edge, as long as the die and wafer alignment on the line.(4) the pressing process is continuously by controlling the rotation wheel is driven by the rotation of a wafer rotating, according to a certain order to suppress.(5) in after the pressing process, prepared template matching. If a deviation to make further adjustments.3.4pressure drum operation standard(1) die on the quality of the products and the smooth pressure drum forming crucial. Therefore, require that the operator must according to the processing situation of choice for mold and timely adjust shim plate.(2) the operator receives the process card, see process card, according to the process card check objects, to confirm the real instruction, one-piece, material. Number, batch number etc.. According to the choice of mold process card.(3) for EHA, EHB head shapes have adopted the 0.82*D standard selection, for DHB, PSH, MD and other special products according to technology card selection of mold, but in principle according to P*0.82/1.15or P*0.82/1.2 standard selection. [1](4) pressing carefully before inspection wafer quality, no seam wafer end is smooth, there is no gap, surface has no cutting slag and defects.(5) a weld in addition to carefully check the end of the wafer wafer defects, at the same time should be checked for weld seam is higher than that of base metal, weld ends of are welding spatter, weld end grinding smooth, there is no crack notch.(6) two or two or more superimposed when pressed, each slice of the joint surface should be clean, according to the circumstances must entrust welding class, the wafer is welded together to suppress.(7) detection of wafer thickness ( the thickest, most thin, whether and process card, measurement of wafer size and process card.(8) suppression must be removed before the inside and outside surface of all debris, to prevent pitting appeared.(9) for general stainless steel materials ( more than 5mm plate ) using Teflon plate mold and the lower mold dressing on surface polished smooth ( necessary nowadays mold to Teflon plate. ) to ensure the surface quality of the workpiece, while in the process of the pressing need to avoid debris into molds and semi-finished products. [6](10) the pressing process, when the wafer is a R shape, must use the corresponding R model measurement, the pressing process should be considered to adjust the pressure deformation degree.(11) pressing is finished, the measurement of plate thickness, measuring arc length. Check surface quality, check end and weld end is smooth ( necessary to polish out the ceremony ).(12) to check the semi-finished product with process card is on the move to the next process ( and sign the name ) by the next process to confirm acceptance before.4.spinning process4.1spinning operationThe spinning process is pressed after the drum head molding process, mainly for large head R and straight edge formation.4.2spinning machine.(1) forming wheel is connected to the corresponding mold, forming in the head inside, mold top with half formed head R and straight edge is tangent to tangent.(2) supporting wheel is also connected and molded wheel mold, forming in the head outside, and a forming wheel tangent.(3) base for fixing head, and the bottom according to head size before and after moving, the head should be installed so that the center of the base and the head of the center in a straight line.(4) the center rod is used for fixing head, and the center and the center of the base is in a straight line.In addition to the motor, a circuit board, is connected to the shaft, anda control console.4.3spinning procedure(1) to undertake pressure drum process card, according to the card to determine the corresponding head spinning.(2) according to the head of the diameter, select the corresponding upper and lower mold.(3) the clamping head, ensure that the head of the center point and the center of the base point in a straight line.(4) to adjust the molding wheel and the head of tangent, then according to the forming wheel position adjustment roller.(5) in the spinning process to observe the forming roller and the supporting roller relative position, and continue to use the template on the line alignment. Until the R reaches the requirements.4.4spinning operation standard(1) spinning wheel material for steel bearings or ductile iron, mold on the quality of the products and can spin forming closely related, therefore the operator must be processed according to choose suitable mold, at the same time, because of the shape of the mold and the surface condition of the quality of the workpiece has a great influence, therefore, before processing and machining process must on the mold for full inspection.(2) according to the process card requirements, confirm wafer, pressure drum or preload semi-finished instruction number, specifications, quantity of material, compliance, and check the quality of surface and end with no defect, abnormal timely and on the procedures of contact, and in a timely manner(3) check the semi-finished end is smooth, with or without notch, crack, surface has no cutting or welding slag, and shall inspect the weld seam is higher than that of base metal, weld ends whether spatter, weld end grinding smooth, there is no crack. [7](4) pressure drum or to the press after the finished product, must checkfor folding, cracking, crack is not conducive to the spinning processing defects.(5) for stainless steel workpiece, through to the pickling method of decontamination.(6) according to the process card selection of mold, general small arc r size requirements as a basis for selecting the internal wheel. (7) according to the different material, thickness of plate and sheet rebound, selection is slightly smaller than the internal wheel circular arc R.(8) for the special requirements of the product, according to its shape design inside the wheel, confirm the mold surface, good polishing processing.(9) spinning processing, in order to prevent scratching and improve the processing performance, suitable lubricant ( grease ) to prevent process heating head appears on the surface of hot cracks and scratches, can also prolong the service life of die.(10) the spinning process, should be considered a workpiece shaping and timely for pressure adjustment.(11) after the molding process, deal with the size, shape, thickness, surface quality inspections, confirmation.(12) molded product with the card with the transfer process to the next process ( in the process card signed their name ) by the procedures under the inspector or monitor check before.5.groove processThe 5.1groove Essentials(1) groove process is a head of the data ( including circumference, total height) to achieve JB/T4746 standard key process. [1](2) groove is in order and cylinder head connection time, make welding more thoroughly.(3) the main groove cutting process and cutting process tools, is the use of plasma cutting.(4) cutting, according to the card on the technological requirements, determine groove type ( inner groove, outside the mouth, X groove ) and determine the groove angle.(5) the groove before the head splashing agent applicator.(6) groove when the first test slope, then a protractor measuring angle, identified in the tolerance range, after adjustment, the whole slope. The 5.2groove operation standard(1) according to the process card to find real, order confirmation No., specification, material, batch number, quantity and check whether the workpiece has a drum kit, crack, delamination, wrinkle, and whether the loss of a round, found problems in a timely manner to contact, processing, the plate thickness of more than 8mm, is suggested to lose the round groove, the following 6mm, tooling plate pressure is groove.(2) stainless steel head, should be in the groove wall smearing splash front head agent, prevent groove, slag spout to head on the wall. (3) head onto the beveling machine before, first confirm the head weight, based on the weight of suitable sling, sling safety inspection.(4) head onto the groove machine, beveling rotary table adjustment screw rod, with a center adjusting position, rotating table, is aligned to the center.(5) groove, according to technology card height and height tolerance groove height ruler to draw lines, confirm the high line, the slope slope, should first slope flat groove, and then the slope groove.(6) outside the mouth or the inner groove angle should be controlled within ± 2.5 tolerance.(7) groove after, should check the head circumference, height, straight edge, angle, if not qualified to repair process, repair.(8) qualified head will remove and clean the slag grinding head internal slag, together with card transfer to the next process ( and sign their name ) by the next process inspector confirmation can be.6.polishing process6.1 polishing process steps(1) according to the card process requirements, identify the need for polishing head.(2) the head rotating table, determine the level of, the clamping head.(3) polishing from edge to center, or from the center to the edge; according to the diameter size determine the head beam, lower speed and working stage, after moving speed.(4) check the polishing condition, appropriate for rework.The 6.2polishing operation standard(1) according to the process card and materials to confirm the product instruction number, specifications, material, batch number, quantity, and check whether the workpiece has a drum kit, crack, delamination defects, and whether the loss of a round, found problems in a timely manner to contact, processing, check the appearance, to determine the need for manual processing, the polishing before hook head to mark.(2) according to the requirements of the choice of using a polishing, polishing pads, and the necessary auxiliary tool.(3) confirm the head weight, based on the weight of suitable sling, and check whether the safety hanger.(4) the head hanging onto a work table, adjust the center, at the same time to ensure that the head is in the basic level (0-5 deviations ).(5) people in the scene when polishing polishing, attention, especially the left centre, speed fast, or outward from a center left, a little pressure to increase, from the edge to the center of pressure during polishing, to a little decrease in polishing head, thin wall, as the case may be mounted shockproof wheel, at the same time attention to mechanical work has no abnormal.(6) after the completion of inspection head polishing, with or without defect, and the necessary contact.(7) the Polish well head with coated packaging, in the process card signed their names, together with the head and process the card with the circulation storage, and by the next inspection approval.封头加工工艺1.焊接工序1.1 焊接操作我们厂常用的焊接方法有：手工焊、氩弧焊、埋弧焊。
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Open Controller Architecture - Past, Present and FutureGunter Pritschow (Co-ordinator), Yusuf Altintas, Francesco Jovane, Yoram Koren, Mamoru Mitsuishi, Shozo Takata, Hendrik van Brussel, Manfred Weck, Kazuo YamazakiAbstractOpen Control Systems are the key enabler for the realization of modular and re-configurable manufacturing systems. The large number of special purpose machines and the high level of automation have led to an increasing importance of open control systems based on vendor neutral standards. This paper gives an overview on the past, present and future of Open Controller Architecture. After reflecting on the different criteria, categories and characteristics of open controllers in general, the CNC products in the market are evaluated and an overview on the world-wide research activities in Europe, North America and Japan is given. Subsequently the efforts to harmonize the different results are described in order to establish a common world-wide standard in the future. Due to the “mix-and-match’’ nature of open controllers concentrated attention must be paid to testing mechanisms in the form of conformance and interoperability tests.Keywords: Open architecture control, CNC, Machine tool1 INTRODUCTIONOpen Architecture Control (OAC) is a well known term in the field of machine control. Since the early nineties several initiatives world-wide have worked on concepts for enabling control vendors, machine tool builders and end-users to benefit more from flexible and agile production facilities. The main aim was the easy implementation and integration of customer-specific controls by means of open interfaces and configuration methods in a vendor-neutral, standardized environment [13][19].The availability and broad acceptance of such systems result in reduced costs and increased flexibility. Software can be reused and user-specific algorithms or applications can be integrated. Users can design their controls according to a given configuration. This trend was forced both by the increasing number of special purpose machines with a high level of automation and the increasing development costs for software (Figure 1).Figure 1: CNC Hardware and software -Actual trend existingIn the past the CNC market was dominated by heterogeneous, device-oriented systems with proprietary hardware and software components. The tight coupling of application software, system software and hardware led to very complex and inflexible systems. Great efforts were made to maintain and further develop the products according to new market requirements. Modern CNC approaches, which comprise extensive functionality to achieve a high quality and flexibility of machining results combined with a reduced processing time, favor PC- based solutions with a homogenous, standardized environment (Figure 2). The structure is software- oriented and configurable due to defined interfaces and software platforms. Open control interfaces are necessary for continuously integrating new advanced functionality into control systems and are important for creating re-configurable manufacturing units [17]. Unbundling hardware and software allows profiting from the short innovation cycles of the semiconductor industry and information technology. With the possibility for reusing software components, the performance of the overall system increases simply by upgrading the hardware platform.Figure 2: PC-based, software-oriented Control SystemsThere are a lot of benefits for suppliers and users of open control systems (Figure 3) [7]. CNC designers and academics benefit from a high degree of openness coveringalso the internal interfaces of the CNC. For CNC users the external openness is much more important. It provides the methods and utilities for integrating user-specific applications into existing controls and for adapting to user-specific requirements, e.g. adaptable user interfaces or collection of machine and production data. The external openness is mainly based on the internal openness but has functional or performance Iimitations .2 STATE OF THE ART2.1 Control Systems and their interfacesControls are highly sophisticated systems due to very strict requirements regarding real-time and reliability. For controlling the complexity of these systems hardware and software interfaces are an essential means. The interfaces of control systems can be divided into two groups-external and internal interfaces (Figure4).External InterfacesThese interfaces connect the control system to superior units, to subordinate units and to the user. They can be divided into programming interfaces and communication interfaces. NC and PLC programming interfaces are harmonized by national or international standards, such as RS-274, DIN 66025 or IEC 61131-3. Communication interfaces are also strongly influenced by standards. Fieldbus systems like SERCOS, Profibus or DeviceNet are used as the interface to drives and 110s. LAN (Local Area Network) networks mainly based on Ethernet and TCP/lP do reflect the interfaces to superior systems.Internal InterfacesInternal interfaces are used for interaction and data- exchange between components that build up the control- system core. An important criterion in this area is the support of real-time mechanisms. To achieve a re-configurable and adaptable control the internal architecture of the control system is based on a platform concept. The main aims are to hide the hardware-specific details from the software components and to establish a defined but flexible way of communication between the software components. An application programming interface(API) ensures these requirements. The whole functionality of a control system is subdivided into several encapsulated, modular software components interacting via the defined API.2.2 Hardware and software structure of control systemsFigure 5 shows different variants for the hardware structures of control systems. Variant a) shows an analog drives interface with position controller in the control system core. Each module of this structure uses its own processor which leads to a large variety of vendor-specific hardware. Combining modules leads to a significant reduction of the number of processors. Variant b) shows intelligent digital drives with integrated control functionality, which result from higher capacity, miniaturization and higher performance of the processors. Variant c) shows a PC-based single processor solution with a real-time extension of the operating system. All control-functions run as software tasks in the PC-based real-time environment.2.3 Market overviewThe controls available in the market provide different levels of openness according to the criteria shown in Figure 6. An important criterion is the use of a standardized computing platform (i.e. hardware, operating system and middleware) as an environment to execute the HMI and CNC software. Besides this, the connectivity of the CNC to upper and lower factory levels must be guaranteed. Application Programming Interfaces (API) are used to integrate third party software in the CNC products. Al though most of today’s controls offer openness concerning the operator-related control functions (Human-Machine Interface, HMI) only few controls allow users to modify their low-level control algorithms to influence the machine-related control functions.Figure 7 gives an overview of the characteristics of today’s control s ystems regarding the degree of openness.Although many control systems provide open interfaces for software integration (e.g. OPC) there is still no common definition of data which is passed back and forth via the programming interface. Therefore, the control systems available on the market today do not implicitly support “plug-and-play” features. To improve this situation, the fieldbus systems can serve as a role model (see Figure 8). The variety of different fieldbus systems has led to the broad consensus that harmonizing the application-oriented interfaces is desirable in order to hide the plurality and the complexity of the systems from the user. Most fieldbus organizations are already using so-called device profiles in order to support the interchangeability of the devices of different vendors.For example, the SERCOS interface standard (IEC61491) for the cyclic and deterministic communication between CNC and drives has defined the semantics forapprox. 400 parameters describing drive and control functions which are used by the devices of different vendors.3 DEFINITIONS AND CATEGORIES OF OPENNESS3.1 DefinitionsThe “Technical Committee of Open Systems” of IEEE defines an open system as follows: “An open system provides capabilities that enable properly implemented applications to run on a variety of platforms from multiple vendors, interoperate with other system applications and present a consistent style of interaction with the user” (IEEE 1003.0).To estimate the openness of a controller the following criteria can be applied (Figure 9):Portability. Application modules (AM) can be used on different platforms without any changes, while maintaining their capabilities.Extendibility. A varying number of AM can run on a platform without any conflicts.Inferoperability. AM work together in a consistent manner and can interchange data in a defined way.Scalability. Depending on the requirements of the user, functionality of the AM and performance and size of the hardware can be adapted.To fulfill the requirements of the IEEE-definition and these criteria of openness, an open control system must be:vendor neutral. This guarantees independence of single proprietary interests.consensus-driven. It is controlled by a group of vendors and users (usually in the form of a user group or an interested group).standards-based. This ensures a wide distribution in the form of standards (national/international standards or de-facto standards).freely available. It is free of charge to any interested party.3.2 Categories of Open Control SystemsIf we speak of openness in control systems, the following categories can be identified (Figure 10):Open HMl: The openness is restricted to the non-real-time part of the control system. Adaptations can be made in user oriented applications.Kernel with restricted openness: The control kernel has a fixed topology, but offers interfaces to insert user-specific filters even for real-time functions.Open Control System: The topology of the control kernel depends on the process. It offers interchangeability, scalability, portability and interoperability.Open control systems that are available today mostly offer the possibility for modifications in the non-real-time part in a fixed software topology. They lack the necessary flexibility and are not based on vendor-neutral standards.3.3 RequirementsA vendor-neutral open control system can only be realized if the control functionality is subdivided in functional units and if well-defined interfaces between these units are specified (Figure 11). Therefore modularity can be identified as the key for an open system architecture. In determining the module complexity there is an obvious trade-off between the degree of openness and the cost of integration [6]. Smaller modules provide a higher level of openness and more options, but increase the complexity and integration costs. Furthermore such a low level of granularity can lead to much higher demands for resources and it may even deteriorate the real-time performance of the overall system.Combining modules in the manner of “mix-and-match’’ requires a comprehensive set of standard Application Programming Interfaces (APIs). For vendor-neutral open control systems the interfaces need to be standardized and broadly accepted. Due to the complexity of such modular systems the definition of a system architecture is recommendable and helpful. This leads to the introduction of so-called system platforms (Figure 12). These platforms encapsulate the specifics of a computing system by absorbing the characteristics of hardware, operating system and communication. The availability of such middleware systems facilitates the easy porting of application software and also the interoperability of application modules even in distributed heterogeneous environments.Due to the possibility to “mix-and-match’’ modules via standardized interfaces the quality of the overall system is determined by the degree of the interoperability between the single modules (see Section 5).4 SYSTEMS ON THE WAY TO THE MARKET4.1 Major international activitiesOSEC (Japan)The OSE (Open System Environment for Manufacturing) consortium was established in December 1994. Three project phases were carried out until March 1999 [1][2][3]. The OSEC Architecture was intended to provide end users, machine makers, control vendors, software vendors, system integrators, etc. a standard platform for industrial machine controllers, with which they can add their own unique values to the industrial machines, and hence promote the technical and commercial development of the industrial machines. The OSEC API is defined in the form of an interface protocol, which is used to exchange messages among controller software components representing the functionality and the real- time cycle. Each functional block can be encapsulated as an object so it is not necessary to deal with how a functional block processes messages to it at architecture level (Figure 13). Although the structure of functional blocks can be defined uniquely by the OSEC architecture from a logical point of view, the system is neither determined nor limited at its implementation phase because there are so many options for implementations. These options may include system contrivances such as device driver, interprocess communication, installation mechanisms such as static library and DLL, hardware factors like selection of controller card, and implementations of software modules added for execution control and/or monitoring of various software. In other words, the implementation model to realize the architecture model is not limited to a particular model. In this way, it is assured to incorporate various ideas in the implementation model depending on the system size or its hardware implementation and/or utilization.JOP (Japan)In parallel to the OSE consortium activities, MSTC formed the Open-Controller Technical Committee (OC- TC) from 1996 to 2000, under the umbrella of JOP (Japanese Open Promotion Group). The objectives of OC-TC were to provide the opportunities for various companies to discuss and work together on the standardization of open controller technologies. The OC- TC was also expected to act as liaison between domestic and international activities in this field. OC-TC was participated by approximately 50 members, which included major Japanese controller vendors, machine tool builders, integrators, users, and academics. Some of the members represented the other groups concerning open controllers such as the OSE consortium and the FA Intranet Promotion Group .One of the working groups was engaged in developing a standard API for interfacing between NC and PC-based HMI. It should be also effective for the communication between NC and an upper level management controller. The work was carried out based on the proposals from the major controller vendors and that from the OSE consortium. The developed specifications were named PAPI and released July, 1999 [4] [5]. PAPI was approved as a JIS (Japan Industrial Standard) technical report and published in October, 2000. To demonstrate the effectiveness of the specifications developed by OC-TC, in Nagoya in October 1999, two CNCs manufactured by different vendors were connected to a Windows NT machine in which the same HMI systems developed by the University of Tokyo were implemented (Figure 14). Since any specific controller architecture is not assumed, PAPI can be implemented in various types of existing CNC systems, such as PC + proprietary NC, PC + NC board, and Software NC on PC+110 board. The HMI system communicates with the CNCs via PAPI which is a function-oriented software library in the programming language C. The PAPI interface is neutralizing the vendor-specific interface by mapping the PAPI calls to the vendor-specific API and protocol.OMAC (USA)The Open Modular Architecture Controllers (OMAC) Users Group is an industry forum to advance the state of controller technology [l0]. An effort was undertaken within OMAC to define API specification for eventual submittal to an established standards body. The OMAC API adopted a component-based approach to achieve plug-and-play modularization, using interface classes to specify the API [11]. For distributed communication, component-based technology uses proxy agents to handle method invocations that cross process boundaries. OMAC API contains diffe rent “sizes” and “types” of reusab le plug-and-play components - component, module, and task - each with a unique Finite State Machine (FSM) model so that component collaboration is performed in a known manner. The term component applies to reusable pieces of software that serves as a building block within an application while the term module refers to a container of components. Tasks are components used to encapsulate programmable functional behavior consisting of a series of steps that run to completion, including support for starting, stopping, restarting, halting, and resuming, and may be run multiple times while a controller is running. Tasks can be used to build controller programs consisting of a series of Transient Tasks, with ability to restart and navigate, or as standalone Resident Tasks to handle specialized controller requirements, (e.g., axis homing or ESTOP).To integrate components, a framework is necessary to formalize the collaborations and other life cycle aspects in which components operate. The OMAC API uses Microsoft Component Object Model (COM) as the initial framework in which to develop components, with the expected benefit that control vendors could then concentrate on application-specific improvements that define their strategic market-share - as opposed to spending valuable programming resources reinventing and maintaining software “plumbing.”The primary problem with COM framework, specifically under the Windows 2000 operating system, is the lack of hard, real-time preemptive scheduling, but third party extensions to Windows 2000 can be used to overcome this requirement.Figure 15 illustrates a sketch of OMAC API controller functionality. The HMI module is responsible for human interaction with a controller including presenting data, handing commands, and monitoring events and in the OMAC API “mirrors” the actual controller with references to all the major modules and components via proxy agents. The Task Coordinator module is responsible for sequencing operations and coordinating the various modules in the system based on programmable Tasks. The Task Coordinator can be considered the highest level Finite State Machine in the controller. A Task Generator module translates an application-specific control program (e.g., RS 274 part program) into a series of application-neutral Transient Tasks. The Axis Group module is responsible for coordinating the motions of individual axes, transforming an incoming motion segment specification into a sequence of equi-time- spaced setpoints for the coordinated axes. The Axis module is responsible for servo control of axis motion, transforming incoming motion setpoints into setpoints for the corresponding actuators 10 points. The Control Law component is responsible for servo control loop calculations to reach specified setpoints. OSACA (Europe)In Europe the ESPRIT project OSACA (Open System Architecture for Controls within Automation Systems) was initiated in 1992 with the aim to unite European interests and to create a vendor-neutral standard for open control systems[9][16].It was supported by major European control vendor and machine tool builders. OSACA reached a mature state already in April 1996 having at its disposal a stable set of specifications and a tested pool for system software. Based on these results, several application-oriented projects were carried out. In 1988 two pilot demonstrators in the automotive industry proved the interoperability of OSACA-compliant controllers and applications. The OSACA association eth currently 35 members from all over the word is the lasting organization to keep and maintain the OSACA-related specifications.The basic technical approach of the OSACA architecture is the hierarchical decomposition of control functionality into so-called functional units (Figure 16).For each of these functional units (e.g. motion control, motion control manager, axescontrol, logic control, etc.) the interfaces are specified by applying object-oriented information models. This technique is similar to the approach of MAP/MMS but with a limited and manageable number of object classes.The data interface consists of several variable objects that support the read and/or write access to data structure(data flow).The data can be of a simple type or of a complex type(array, structure, union).By using formal templates(Figure17) all the characteristics of a single interface object are specified. These elements cover the name (e.g, “mc-active-feed-override”), the type (e.g. UNS32: 32-bit unsigned value), the scaling (e.g. 0.l%),the range and the access rights (read only, to all the major modules and components via proxy write only, read/write) of the data. An additional description is to avoid misinterpretations of the use of the data. The process interface consists of several process objects that are used to describe the dynamic behavior (control flow) of the application modules by means of finite state machine (FSM). The state machines are described by static states, dynamic states and transitions to change the states of a given state-machine. The transitions can handle input and output parameters to pass data between application modules via the communication platform. The formal template for such process interfaces consists of an unambiguous description and the following attributes: list of static states (identifier, list of possible transitions), list of dynamic states (identifier) and a list of transitions (input parameters, output parameters, return codes). The process interface can also be used to activate application-specific functions in form of procedure calls. The interoperability of distributed application modules is supported by an infrastructure (so-called OSACA platform) which comprises client-server principles, synchronous and asynchronous calls and event handling via any underlying communication protocol and media (e.g. by using the TCP/lP protocol). A dedicated configuration runtime system is handling the system’s startup and shutdown. Besides, it also allows an easy reconfiguration of the system.开放式控制器体系结构- 过去，现在和未来摘要开放式控制系统是用于模块化和可重新配置制造系统实现的关键推动者。