机械方面论文翻译
Manufacturing Engineering and Technology(机械类英文文献+翻译)
Manufacturing Engineering and Technology—MachiningSerope kalpakjian；Steven R.Schmid机械工业出版社2004年3月第1版20.9 MACHINABILITYThe machinability of a material usually defined in terms of four factors:1、Surface finish and integrity of the machined part;2、Tool life obtained;3、Force and power requirements;4、Chip control.Thus, good machinability good surface finish and integrity, long tool life, and low force And power requirements. As for chip control, long and thin (stringy) cured chips, if not broken up, can severely interfere with the cutting operation by becoming entangled in the cutting zone.Because of the complex nature of cutting operations, it is difficult to establish relationships that quantitatively define the machinability of a material. In manufacturing plants, tool life and surface roughness are generally considered to be the most important factors in machinability. Although not used much any more, approximate machinability ratings are available in the example below.20.9.1 Machinability Of SteelsBecause steels are among the most important engineering materials (as noted in Chapter 5), their machinability has been studied extensively. The machinability of steels has been mainly improved by adding lead and sulfur to obtain so-called free-machining steels.Resulfurized and Rephosphorized steels. Sulfur in steels forms manganese sulfide inclusions (second-phase particles), which act as stress raisers in the primary shear zone. As a result, the chips produced break up easily and are small; this improves machinability. The size, shape, distribution, and concentration of these inclusions significantly influence machinability. Elements such as tellurium and selenium, which are both chemically similar to sulfur, act as inclusion modifiers inresulfurized steels.Phosphorus in steels has two major effects. It strengthens the ferrite, causing increased hardness. Harder steels result in better chip formation and surface finish. Note that soft steels can be difficult to machine, with built-up edge formation and poor surface finish. The second effect is that increased hardness causes the formation of short chips instead of continuous stringy ones, thereby improving machinability.Leaded Steels. A high percentage of lead in steels solidifies at the tip of manganese sulfide inclusions. In non-resulfurized grades of steel, lead takes the form of dispersed fine particles. Lead is insoluble in iron, copper, and alumin um and their alloys. Because of its low shear strength, therefore, lead acts as a solid lubricant (Section 32.11) and is smeared over the tool-chip interface du ring cutting. This behavior has been verified by the presence of high concentra tions of lead on the tool-side face of chips when machining leaded steels.When the temperature is sufficiently high-for instance, at high cutting spee ds and feeds (Section 20.6)—the lead melts directly in front of the tool, acting as a liquid lubricant. In addition to this effect, lead lowers the shear stress in the primary shear zone, reducing cutting forces and power consumption. Lead can be used in every grade of steel, such as 10xx, 11xx, 12xx, 41xx, etc. Le aded steels are identified by the letter L between the second and third numeral s (for example, 10L45). (Note that in stainless steels, similar use of the letter L means “low carbon,”a condition that improves their corrosion resistance.)However, because lead is a well-known toxin and a pollutant, there are se rious environmental concerns about its use in steels (estimated at 4500 tons of lead consumption every year in the production of steels). Consequently, there is a continuing trend toward eliminating the use of lead in steels (lead-free ste els). Bismuth and tin are now being investigated as possible substitutes for lea d in steels.Calcium-Deoxidized Steels. An important development is calcium-deoxidize d steels, in which oxide flakes of calcium silicates (CaSo) are formed. These f lakes, in turn, reduce the strength of the secondary shear zone, decreasing tool-chip interface and wear. Temperature is correspondingly reduced. Consequently, these steels produce less crater wear, especially at high cutting speeds.Stainless Steels. Austenitic (300 series) steels are generally difficult to mac hine. Chatter can be s problem, necessitating machine tools with high stiffness. However, ferritic stainless steels (also 300 series) have good machinability. M artensitic (400 series) steels are abrasive, tend to form a built-up edge, and req uire tool materials with high hot hardness and crater-wear resistance. Precipitati on-hardening stainless steels are strong and abrasive, requiring hard and abrasio n-resistant tool materials.The Effects of Other Elements in Steels on Machinability. The presence of aluminum and silicon in steels is always harmful because these elements com bine with oxygen to form aluminum oxide and silicates, which are hard and a brasive. These compounds increase tool wear and reduce machinability. It is es sential to produce and use clean steels.Carbon and manganese have various effects on the machinability of steels, depending on their composition. Plain low-carbon steels (less than 0.15% C) c an produce poor surface finish by forming a built-up edge. Cast steels are mor e abrasive, although their machinability is similar to that of wrought steels. To ol and die steels are very difficult to machine and usually require annealing pr ior to machining. Machinability of most steels is improved by cold working, w hich hardens the material and reduces the tendency for built-up edge formation.Other alloying elements, such as nickel, chromium, molybdenum, and vana dium, which improve the properties of steels, generally reduce machinability. T he effect of boron is negligible. Gaseous elements such as hydrogen and nitrog en can have particularly detrimental effects on the properties of steel. Oxygen has been shown to have a strong effect on the aspect ratio of the manganese sulfide inclusions; the higher the oxygen content, the lower the aspect ratio an d the higher the machinability.In selecting various elements to improve machinability, we should consider the possible detrimental effects of these elements on the properties and strengt h of the machined part in service. At elevated temperatures, for example, lead causes embrittlement of steels (liquid-metal embrittlement, hot shortness; see Se ction 1.4.3), although at room temperature it has no effect on mechanical prop erties.Sulfur can severely reduce the hot workability of steels, because of the fo rmation of iron sulfide, unless sufficient manganese is present to prevent such formation. At room temperature, the mechanical properties of resulfurized steels depend on the orientation of the deformed manganese sulfide inclusions (aniso tropy). Rephosphorized steels are significantly less ductile, and are produced so lely to improve machinability.20.9.2 Machinability of Various Other MetalsAluminum is generally very easy to machine, although the softer grades te nd to form a built-up edge, resulting in poor surface finish. High cutting speed s, high rake angles, and high relief angles are recommended. Wrought aluminu m alloys with high silicon content and cast aluminum alloys may be abrasive; they require harder tool materials. Dimensional tolerance control may be a pro blem in machining aluminum, since it has a high thermal coefficient of expans ion and a relatively low elastic modulus.Beryllium is similar to cast irons. Because it is more abrasive and toxic, t hough, it requires machining in a controlled environment.Cast gray irons are generally machinable but are. Free carbides in castings reduce their machinability and cause tool chipping or fracture, necessitating to ols with high toughness. Nodular and malleable irons are machinable with hard tool materials.Cobalt-based alloys are abrasive and highly work-hardening. They require sharp, abrasion-resistant tool materials and low feeds and speeds.Wrought copper can be difficult to machine because of built-up edge form ation, although cast copper alloys are easy to machine. Brasses are easy to ma chine, especially with the addition pf lead (leaded free-machining brass). Bronz es are more difficult to machine than brass.Magnesium is very easy to machine, with good surface finish and prolong ed tool life. However care should be exercised because of its high rate of oxi dation and the danger of fire (the element is pyrophoric).Molybdenum is ductile and work-hardening, so it can produce poor surfac e finish. Sharp tools are necessary.Nickel-based alloys are work-hardening, abrasive, and strong at high tempe ratures. Their machinability is similar to that of stainless steels.Tantalum is very work-hardening, ductile, and soft. It produces a poor surf ace finish; tool wear is high.Titanium and its alloys have poor thermal conductivity (indeed, the lowest of all metals), causing significant temperature rise and built-up edge; they can be difficult to machine.Tungsten is brittle, strong, and very abrasive, so its machinability is low, although it greatly improves at elevated temperatures.Zirconium has good machinability. It requires a coolant-type cutting fluid, however, because of the explosion and fire.20.9.3 Machinability of Various MaterialsGraphite is abrasive; it requires hard, abrasion-resistant, sharp tools.Thermoplastics generally have low thermal conductivity, low elastic modul us, and low softening temperature. Consequently, machining them requires tools with positive rake angles (to reduce cutting forces), large relief angles, small depths of cut and feed, relatively high speeds, and proper support of the work piece. Tools should be sharp.External cooling of the cutting zone may be necessary to keep the chips f rom becoming “gummy”and sticking to the tools. Cooling can usually be achi eved with a jet of air, vapor mist, or water-soluble oils. Residual stresses may develop during machining. To relieve these stresses, machined parts can be an nealed for a period of time at temperatures ranging from to ( to ), and then cooled slowly and uniformly to room temperature.Thermosetting plastics are brittle and sensitive to thermal gradients during cutting. Their machinability is generally similar to that of thermoplastics.Because of the fibers present, reinforced plastics are very abrasive and are difficult to machine. Fiber tearing, pulling, and edge delamination are significa nt problems; they can lead to severe reduction in the load-carrying capacity of the component. Furthermore, machining of these materials requires careful rem oval of machining debris to avoid contact with and inhaling of the fibers.The machinability of ceramics has improved steadily with the development of nanoceramics (Section 8.2.5) and with the selection of appropriate processi ng parameters, such as ductile-regime cutting (Section 22.4.2).Metal-matrix and ceramic-matrix composites can be difficult to machine, d epending on the properties of the individual components, i.e., reinforcing or wh iskers, as well as the matrix material.20.9.4 Thermally Assisted MachiningMetals and alloys that are difficult to machine at room temperature can be machined more easily at elevated temperatures. In thermally assisted machinin g (hot machining), the source of heat—a torch, induction coil, high-energy bea m (such as laser or electron beam), or plasma arc—is forces, (b) increased too l life, (c) use of inexpensive cutting-tool materials, (d) higher material-removal rates, and (e) reduced tendency for vibration and chatter.It may be difficult to heat and maintain a uniform temperature distribution within the workpiece. Also, the original microstructure of the workpiece may be adversely affected by elevated temperatures. Most applications of hot machi ning are in the turning of high-strength metals and alloys, although experiment s are in progress to machine ceramics such as silicon nitride.SUMMARYMachinability is usually defined in terms of surface finish, tool life, force and power requirements, and chip control. Machinability of materials depends n ot only on their intrinsic properties and microstructure, but also on proper sele ction and control of process variables.20.9 可机加工性一种材料的可机加工性通常以四种因素的方式定义：1、分的表面光洁性和表面完整性。
机械的工作英文作文
机械的工作英文作文英文：As a mechanical engineer, my work involves designing, developing, and testing mechanical devices and systems. This can range from simple machines like gears and pulleys to complex systems like engines and robots. I work closely with other engineers and technicians to ensure that the products we create meet the needs of our clients and are safe and reliable.One of the most challenging aspects of my job is troubleshooting. When a machine or system isn't working properly, it's up to me to figure out what's causing the problem and come up with a solution. This often involves a lot of trial and error, as well as creative thinking and problem-solving skills.Another important part of my job is staying up-to-date with the latest technology and industry trends. This meansattending conferences and workshops, reading industry publications, and networking with other professionals in my field. By staying informed, I can ensure that the products I design and develop are cutting-edge and meet the needs of our clients.Overall, my job as a mechanical engineer is challenging but rewarding. I enjoy the problem-solving aspect of my work and the satisfaction of seeing a project through from conception to completion.中文：作为一名机械工程师，我的工作涉及设计、开发和测试机械设备和系统。
机械类英语作文模板
机械类英语作文模板英文回答：Introduction。
Mechanical engineering is an incredibly vast anddiverse field that encompasses the design, development, and operation of machines. It is a highly interdisciplinaryfield that draws upon principles from physics, mathematics, and materials science to create solutions to real-world problems. Mechanical engineers play a vital role in many industries, including transportation, manufacturing, energy, and healthcare.Education and Training。
To become a mechanical engineer, a strong foundation in mathematics and science is essential. Most mechanical engineers hold a bachelor's degree in mechanicalengineering from an accredited university. Some may alsochoose to pursue a master's degree or doctorate in mechanical engineering or a related field.Career Opportunities。
Mechanical engineers are in high demand across a wide range of industries. Some of the most common job titles for mechanical engineers include:Design Engineer。
机械作文300字英文
机械作文300字英文英文：Mechanical engineering is a fascinating field that involves the design, development, and manufacturing of various types of machinery. As a mechanical engineer, I have had the opportunity to work on a wide range of projects, from designing and building robots to developing new types of engines for cars.One of the most interesting projects I have worked on was designing a new type of prosthetic arm for amputees. This involved working closely with medical professionals and amputees themselves to understand their needs and design a prosthetic that would be both functional and comfortable to wear. We used advanced materials and manufacturing techniques to create a lightweight and durable prosthetic that could be customized to fit each individual's needs.Another project that I found particularly challenging was designing a new type of engine for a hybrid car. This involved balancing the need for power and efficiency while also considering environmental factors such as emissions. We used computer simulations and physical testing to optimize the design and ended up with an engine that was both powerful and environmentally friendly.Overall, I love being a mechanical engineer because it allows me to use my creativity and problem-solving skills to design and build things that make a difference in people's lives.中文：机械工程是一个迷人的领域，涉及各种类型机械的设计、开发和制造。
机械专业英语短文带翻译
机械工程师的关键责任之一是设计与分析机械系统。这涉及使用计算机辅助设计（CAD）软件创建系统的详细三维模型，并在不同条件下模拟其性能。通过分析作用于系统组件的力、应力和振动，机械工程师可以优化设计，确保安全、可靠和高效。
Case Study: Designing an Automotive Suspension System
案例研究：汽车悬挂系统设计
例如，让我们考虑一下汽车悬挂系统的设计。悬挂系统负责在保持车辆稳定控制的同时提供平稳的行驶。机械工程师使用CAD软件设计悬挂系统的各个组件，例如弹簧、减振器和控制臂。
在完成初始设计后，工程师将使用有限元分析（FEA）软件对系统进行分析。这样可以模拟系统在不同的道路条件下（如坑洼或减速带）的行为。通过分析组件中的应力和位移，工程师可以确定潜在的设计问题，并进行必要的修改，以改善悬挂系统的性能和安全性。
For example, let's consider the design of an automotive suspension system. A suspension system is responsible for providing a smooth ride while maintaining the stability and control of the vehicle. A mechanical engineer would use CAD software to design the various components of the suspension system, such as the springs, dampers, and control arms.
After the initial design is complete, the engineer would then analyze the system using finite element analysis (FEA) software. This allows them to simulate the behavior of the system under different road conditions, such as potholes or speed bumps. By analyzing the stresses and displacements in the components, the engineer can identify potential design issues and make necessary modifications to improve the performance and safety of the suspension system.
机械专业毕业论文中英文翻译--在全接触条件下,盘式制动器摩擦激发瞬态热弹性不稳定的研究
Frictionally excited thermoelastic instability in disc brakes—Transientproblem in the full contact regimeAbstractExceeding the critical sliding velocity in disc brakes can cause unwanted forming of hot spots, non-uniform distribution of contact pressure, vibration, and also, in many cases, permanent damage of the disc. Consequently, in the last decade, a great deal of consideration has been given to modeling methods of thermo elastic instability (TEI), which leads to these effects. Models based on the finite element method are also being developed in addition to the analytical approach. The analytical model of TEI development described in the paper by Lee and Barber [Frictionally excited thermo elastic instability in automotive disk brakes. ASME Journal of Tribology 1993;115:607–14] has been expanded in the presented work. Specific attention was given to the modification of their model, to catch the fact that the arc length of pads is less than the circumference of the disc, and to the development of temperature perturbation amplitude in the early stage of breaking, when pads are in the full contact with the disc. A way is proposed how to take into account both of the initial non-flatness of the disc friction surface and change of the perturbation shape inside the disc in the course of braking.Keywords: Thermo elastic instability; TEI; Disc brake; Hot spots1. IntroductionFormation of hot spots as well as non-uniform distribution of the contact pressure is an unwanted effect emerging in disc brakes in the course of braking or during engagement of a transmission clutch. If the sliding velocity is high enough, this effect can become unstable and can result in disc material damage, frictional vibration, wear, etc. Therefore, a lot of experimental effort is being spent to understand better this effect (cf. Refs.) or to model it in the most feasible fashion. Barber described the thermo elastic instability (TEI)as the cause of the phenomenon. Later Dow and Burton and Burton et al.introduced a mathematical model to establish critical sliding velocity for instability, where two thermo elastic half-planes are considered in contact along their common interface. It is in a work by Lee and Barber that the effect of the thickness was considered and that a model applicable for disc brakes was proposed. Lee and Barber’s model is made up with a metallic layer sliding between twohalf-planes of frictional material. Only recently a parametric analysis of TEI in disc brakes was made or TEI in multi-disc clutches and brakes was modeled. The evolution of hot spots amplitudes has been addressed in Refs. Using analytical approach or the effect of intermittent contact was considered. Finally, the finite element method was also applied to render the onset of TEI (see Ref.).The analysis of nonlinear transient behavior in the mode, when separated contact regions occur, is even accomplished in Ref. As in the case of other engineering problems of instability, it turns out that a more accurate prediction by mathematical modeling is often questionable. This is mainly imparted by neglecting various imperfections and random fluctuations or by the impossibility to describe all possible influences appropriately. Therefore, some effort aroused to interpret results of certain experiments in addition to classical TEI (see, e.g.Ref).This paper is related to the work by Lee and Barber [7].Using an analytical approach, it treats the inception of TEI and the development of hot spots during the full contact regime in the disc brakes. The model proposed in Section 2 enables to cover finite thickness of both friction pads and the ribbed portion of the disc. Section 3 is devoted to the problems of modeling of partial disc surface contact with the pads. Section 4 introduces the term of ‘‘thermal capacity of perturbation’’ emphasizing its association with the value of growth rate, or the sliding velocity magnitude. An analysis of the disc friction surfaces non-flatness and its influence on initial amplitude of perturbations is put forward in the Section 5. Finally, the Section 6 offers a model of temperature perturbation development initiated by the mentioned initial discnon-flatness in the course of braking. The model being in use here comes from a differential equation that covers the variation of the‘‘thermal capacity’’ during the full contact regime of the braking.2. Elaboration of Lee and Barber modelThe brake disc is represented by three layers. The middle one of thickness 2a3 stands for the ribbed portion of the disc with full sidewalls of thickness a2 connected to it. The pads are represented by layers of thickness a1, which are immovable and pressed to each other by a uniform pressure p. The brake disc slips in between these pads at a constant velocity V.We will investigate the conditions under which a spatially sinusoidal perturbation in the temperature and stress fields can grow exponentially with respect to the time in a similar manner to that adopted by Lee and Barber. It is evidenced in their work [7] that it is sufficient to handle only the antisymmetric problem. The perturbations that are symmetric with respect to the midplane of the disc can grow at a velocity well above the sliding velocity V thus being made uninteresting.Let us introduce a coordinate system （x1; y1）fixed to one of the pads (see Fig. 1) thepoints of contact surface between the pad and disc having y1 = 0. Furthermore, let acoordinate system （x2; y2）be fixed to the disc with y2=0 for the points of the midplane. We suppose the perturbation to have a relative velocity ci with respect to the layer i, and the coordinate system （x; y）to move together with the perturbated field. Then we can writeV = c1 -c2; c2 = c3; x = x1 -c1t = x2 -c2t,x2 = x3; y = y2 =y3 =y1 + a2 + a3.We will search the perturbation of the uniform temperature field in the formand the perturbation of the contact pressure in the formwhere t is the time, b denotes a growth rate, subscript I refers to a layer in the model, and j =-1½is the imaginary unit. The parameter m=m（n）=2pin/cir =2pi/L, where n is the number of hot spots on the circumference of the disc cir and L is wavelength of perturbations. The symbols T0m and p0m in the above formulae denote the amplitudes of initial non-uniformities (e.g. fluctuations). Both perturbations (2) and (3) will be searched as complex functions their real part describing the actual perturbation of temperature or pressure field.Obviously, if the growth rate b<0, the initial fluctuations are damped. On the other hand, instability develops ifB〉0.2.1. Temperature field perturbationHeat flux in the direction of the x-axis is zero when the ribbed portion of the disc is considered. Next, let us denote ki = Ki/Qicpi coefficient of the layer i temperature diffusion. Parameters Ki, Qi, cpi are, respectively, the thermal conductivity, density and specific heat of the material for i =1,2. They have been re-calculated to the entire volume of the layer (i = 3) when the ribbed portion of the disc is considered. The perturbation of the temperature field is the solution of the equationsWith and it will meet the following conditions:1，The layers 1 and 2 will have the same temperature at the contact surface2，The layers 2 and 3 will reach the same temperature and the same heat flux in the direction y,3，Antisymmetric condition at the midplaneThe perturbations will be zero at the external surface of a friction pad(If, instead, zero heat flux through external surface has been specified, we obtain practically identical numerical solution for current pads).If we write the temperature development in individual layers in a suitable formwe obtainwhereand2.2. Thermo elastic stresses and displacementsFor the sake of simplicity, let us consider the ribbed portion of the disc to be isotropic environment with corrected modulus of elasticity though, actually, the stiffness of this layer in the direction x differs from that in the direction y. Such simplification is, however, admissible as the yielding central layer 3 practically does not take effect on the disc flexural rigidity unlike full sidewalls (layer 2). Given a thermal field perturbation, we can express the stress state and displacements caused by this perturbation for any layer. The thermo elastic problem can be solved by superimposing a particular solution on the general isothermal solution. We look for the particular solution of a layer in form of a strain potential. The general isothermal solution is given by means of the harmonic potentials after Green and Zerna (see Ref.[18]) and contains four coefficients A, B, C, D for every layer. The relateddisplacement and stress field components are written out in the Appendix A.在全接触条件下，盘式制动器摩擦激发瞬态热弹性不稳定的研究摘要超过临界滑动盘式制动器速度可能会导致形成局部过热，不统一的接触压力，振动分布，而且，在多数情况下，会造成盘式制动闸永久性损坏。
机械类英语论文及翻译
Mechanical DesignAbstract:A machine is a combination of mechanisms and other components which transforms, transmits. Examples are engines, turbines, vehicles, hoists, printing presses, washing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term "mechanical design" is used in a broader sense than "machine design" to include their design. the motion and structural aspects and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers.Keywords: Mechanical Design ；Rules for Design ；Design ProcessThe Design ProcessDesigning starts with a need real.Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly.In the design preliminary stage, should allow to design the personnel fullyto display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive cost. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles of mechanics, such as those of static for reaction forces and for the optimum utilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress and deflection; of physical behavior of materials; and of fluid mechanics for lubrication and hydrodynamic drives. The analyses may be made by the same engineer who conceived the arrangement of mechanisms, or, in a large company, they may be made by a separate analysis division or research group. Design is a reiterative and cooperative process, whetherdone formally or informally, and the analyst can contribute to phases other than his own. Product design requires much research and development. Many Concepts of an idea must be studied, tried, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems.Product liability suits designers and forced in material selection, using the best program. In the process of material, the most common problems for five (a) don't understand or not use about the latest application materials to the best information, (b) failed to foresee and consider the reasonable use material may (such as possible, designers should further forecast and consider due to improper use products. In recent years, many products liability in litigation, the use of products and hurt the plaintiff accused manufacturer, and won the decision), (c) of the materials used all or some of the data, data, especially when the uncertainty long-term performance data is so, (d) quality control method is not suitable and unproven, (e) by some completely incompetent persons choose materials.Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to thesuitable procedure, may greatly reduce the lawsuit the quantity.May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding.Finally, a design based upon function, and a prototype may be built. If its tests are satisfactory, the initial design will undergo certain modifications that enable it to be manufactured in quantity at a lower cost. During subsequent years of manufacture and service, the design is likely to undergo changes as new ideas are conceived or as further analyses based upon tests and experience indicate alterations. Sales appeal.Some Rules for DesignIn this section it is suggested that, applied with a creative attitude, analyses can lead to important improvements and to the conception and perfection of alternate, perhaps more functional, economical,and durable products.To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.1. A creative use of need of physical properties and control process.2. Recognize functional loads and their significance.3. Anticipate unintentional loads.4. Devise more favorable loading conditions.5. Provide for favorable stress distribution and stiffness with minimum weight.6. Use basic equations to proportion and optimize dimensions.7. Choose materials for a combination of properties.8. Select carefully, stock and integral components.9. Modify a functional design to fit the manufacturing process and reduce cost.10. Provide for accurate location and noninterference of parts in assembly.Machinery design covers the following contents.1. Provides an introduction to the design process , problem formulation ,safety factors.2. Reviews the material properties and static and dynamic loading analysis ,Including beam , vibration and impact loading.3. Reviews the fundamentals of stress and defection analysis.4. Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery.5. Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses ,and surface fatigue.6. Investigates shaft design using the fatigue-analysis techniques.7. Discusses fluid-film and rolling-element bearing theory and application8. Gives a thorough introduction to the kinematics, design and stress analysis of spur gears , and a simple introduction to helical ,bevel ,and worm gearing.9. Discusses spring design including compression ,extension and torsion springs.10. Deals with screws and fasteners including power screw and preload fasteners.11. Introduces the design and specification of disk and drum clutches and brakes.Machine DesignThe complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge.One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of thematerial, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations.Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM). How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process. Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved.This generally is through the oral discussion, the schematic diagram and the writing material carries on.If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productMust regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainlycannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.外文论文翻译译文机械设计摘要：机器是由机械装置和其它组件组成的。
机械类英语论文及翻译
机械类英语论文及翻译Mechanical design involves the n of machines。
which are composed of mechanisms and other components that can transform and transmit ___ machines include engines。
turbines。
vehicles。
hoists。
printing presses。
washing machines。
and ___ and methods of design that apply to machines also apply to ___。
the term "mechanical design" is used in a broader sense than "machine design" to include their design.When ___。
___ to take into account。
The n and structural aspects of the device。
as well as the ___。
___ apply not only to machines but also to other mechanical devices。
such as switches。
cams。
valves。
vessels。
and mixers.Mechanical design is a critical field in ___ disciplines。
It plays an essential role in the ___ the success of a mechanical design project。
it is essential to follow a set of rules for design。
机械动力学论文外文翻译文献
机械运动和动力学外文翻译文献英文资料Kinematics and dynamics of machineryOne princple aim of kinemarics is to creat the designed motions of the subject mechanical parts and then mathematically compute the positions, velocities ,and accelerations ,which those motions will creat on the parts. Since ,for most earthbound mechanical systems ,the mass remains essentially constant with time,defining the accelerations as a function of time then also defines the dynamic forces as a function of time. Stress,in turn, will be a function of both applied and inerials forces . since engineering design is charged with creating systems which will not fail during their expected service life,the goal is to keep stresses within acceptable limits for the materials chosen and the environmental conditions encountered. This obvisely requies that all system forces be defined and kept within desired limits. In mechinery , the largest forces encountered are often those due to the dynamics of the machine itself. These dynamic forces are proportional to acceletation, which brings us back to kinematics ,the foundation of mechanical design. Very basic and early decisions in the design process invovling kinematics wii prove troublesome and perform badly.Any mechanical system can be classified according to the number of degree of freedom which it possesses.the systems DOF is equal to the number of independent parameters which are needed to uniquely define its posion in space at any instant of time.A rigid body free to move within a reference frame will ,in the general case, have complex motoin, which is simultaneous combination of rotation and translation. In three-dimensional space , there may be rotation about any axis and also simultaneous translation which can be resoled into componention along three axes, in a plane ,or two-dimentional space ,complex motion becomes a combination of simultaneous along two axes in the plane. For simplicity ,we will limit our present discusstions to the case of planar motion:Pure rotation the body pessesses one point (center of rotation)which has no motion with respect to the stationary frame of reference. All other points on the body describe arcs about that center. A reference line drawn on the body through the center changes only its angulai orientation.Pure translation all points on the body describe parallel paths. A reference line drawn on thebody changes its linear posion but does not change its angular oriention.Complex motion a simulaneous combination of rotion and translationm . any reference line drawn on the body will change both its linear pisition and its angular orientation. Points on the body will travel non-parallel paths ,and there will be , at every instant , a center of rotation , which will continuously change location.Linkages are the bacis building blocks of all mechanisms. All common forms of mechanisms (cams , gears ,belts , chains ) are in fact variations of linkages. Linkages are made up of links and kinematic pairs.A link is an (assumed)rigid body which possesses at least two or more links (at their nodes), which connection allows some motion, or potential motion,between the connected links.The term lower pair is used tohe moving parts .we next want te use newton’s second law to caculate the dynamic forces, but to do so we need to know the masses of all the moving parts which have these known acceletations. These parts do not exit yet ! as with any design in order to make a first pass at the caculation . we will then have to itnerate to better an better solutions as we generate more information.A first estimate of your parts’masses can be obtained by assuming some reasonable shapes and size for all the parts and choosing approriate materials. Then caculate the volume of each part and multipy its volume by material’s mass density (not weight density ) to obtain a first approximation of its mass . these mass values can then be used in Newton’s equation.How will we know whether our chosen sizes and shapes of links are even acceptable, let alone optimal ? unfortunately , we will not know untill we have carried the computations all the way through a complete stress and deflection analysis of the parts. It it often the case ,especially with long , thin elements such as shafts or slender links , that the deflections of the parts, redesign them ,and repeat the force ,stress ,and deflection analysis . design is , unavoidably ,an iterative process .It is also worth nothing that ,unlike a static force situation in which a failed design might be fixed by adding more mass to the part to strenthen it ,to do so in a dynamic force situation can have a deleterious effect . more mass with the same acceleration will generate even higher forces and thus higher stresses ! the machine desiger often need to remove mass (in the right places) form parts in order to reduce the stesses and deflections due to F=ma, thus the designer needs to have a good understanding of both material properties and stess and deflection analysis to properlyshape and size parts for minimum mass while maximzing the strength and stiffness needed to withstand the dynamic forces.One of the primary considerations in designing any machine or strucre is that the strength must be sufficiently greater than the stress to assure both safety and reliability. To assure thatmechanical parts do not fail in service ,it is necessary to learn why they sometimes do fail. Then we shall be able to relate the stresses with the strenths to achieve safety .Ideally, in designing any machine element,the engineer should have at his disposal should have been made on speciments having the same heat treatment ,surface roughness ,and size as the element he prosses to design ;and the tests should be made under exactly the same loading conditions as the part will experience in service . this means that ,if the part is to experience a bending and torsion,it should be tested under combined bending and torsion. Such tests will provide very useful and precise information . they tell the engineer what factor of safety to use and what the reliability is for a given service life .whenever such data are available for design purposes,the engineer can be assure that he is doing the best justified if failure of the part may endanger human life ,or if the part is manufactured in sufficiently large quantities. Automobiles and refrigrerators, for example, have very good reliabilities because the parts are made in such large quantities that they can be thoroughly tested in advance of manufacture , the cost of making these is very low when it is divided by the total number of parts manufactrued.You can now appreciate the following four design categories :(1)failure of the part would endanger human life ,or the part ismade in extremely large quantities ;consequently, an elaborate testingprogram is justified during design .(2)the part is made in large enough quantities so that a moderate serues of tests is feasible.(3)The part is made in such small quantities that testing is not justified at all ; or the design must be completed so rapidlly that there is not enough time for testing.(4) The part has already been designed, manufactured, and tested and found to be unsatisfactory. Analysis is required to understand why the part is unsatisfactory and what to do to improve it .It is with the last three categories that we shall be mostly concerned.this means that the designer will usually have only published values of yield strenth , ultimate strength,and percentage elongation . with this meager information the engieer is expected to design against static and dynamic loads, biaxial and triaxial stress states , high and low temperatures,and large and small parts! The data usually available for design have been obtained from the simple tension test , where the load was applied gradually and the strain given time to develop. Yet these same data must be used in designing parts with complicated dynamic loads applied thousands of times per minute . no wonder machine parts sometimes fail.To sum up, the fundamental problem of the designer is to use the simple tension test data and relate them to the strength of the part , regardless of the stress or the loading situation.It is possible for two metal to have exactly the same strength and hardness, yet one of these metals may have a supeior ability to aborb overloads, because of the property called ductility.Dutility is measured by the percentage elongation which occurs in the material at frature. The usual divding line between ductility and brittleness is 5 percent elongation. Amaterial having less than 5 percent elongation at fracture is said to bebrittle, while one having more is said to be ductile.The elongation of a material is usuallu measured over 50mm gauge length.siece this did not a measure of the actual strain, another method of determining ductility is sometimes used . after the speciman has been fractured, measurements are made of the area of the cross section at the fracture. Ductility can then be expressed as the percentage reduction in cross sectional area.The characteristic of a ductile material which permits it to aborb largeoverloads is an additional safety factot in design. Ductility is also important because it is a measure of that property of a material which permits it to be cold-worked .such operations as bending and drawing are metal-processing operations which require ductile materials.When a materals is to be selected to resist wear , erosion ,or plastic deformaton, hardness is generally the most important property. Several methods of hardness testing are available, depending upon which particular property is most desired. The four hardness numbers in greatest usse are the Brinell, Rockwell,Vickers, and Knoop.Most hardness-testing systems employ a standard load which is applied to a ball or pyramid in contact with the material to be tested. The hardness is an easy property to measure , because the test is nondestructive and test specimens are not required . usually the test can be conducted directly on actual machine element .Virtually all machines contain shafts. The most common shape for shafts is circular and the cross section can be either solid or hollow (hollow shafts can result in weight savings). Rectangular shafts are sometimes used ,as in screw driver bladers ,socket wrenches and control knob stem.A shaft must have adequate torsional strength to transmit torque and not be over stressed. If must also be torsionally stiff enough so that one mounted component does not deviate excessively from its original angular position relative to a second component mounted on the same shaft. Generally speaking,the of length between bearing supports.In addition .the shaft must be able to sustain a combination of bending and torsional loads. Thus an equivalent load must be considered which takes into account both torsion and bending . also ,the allowable stress must contain a factor of safety which includes fatigue, since torsional and bending stress reversals occur.For fiameters less than 3 in ,the usual shaft material is cold-rolled steel containing about 0.4 percent carbon. Shafts ate either cold-rolled or forged in sizes from 3in. to 5 in. for sizes above 5 in. shafts are forged and machined to size . plastic shafts are widely used for light loadapplications . one advantage of using plastic is safty in electrical applications, since plastic is a poor confuctor of electricity.Components such as gears and pulleys are mounted on shafts by means of key. The design of the key and the corresponding keyway in the shaft must be properly evaluated. For example, stress concentrations occur in shafts due to keyways , and the material removed to form the keyway further weakens the shaft.If shafts are run at critical speeds , severe vibrations can occur which can seriously damage a machine .it is important to know the magnitude of these critical speeds so that they can be avoided. As a general rule of thumb , the difference betweem the operating speed and the critical speed should be at least 20 percent.Many shafts are supported by three or more bearings, which means that the problem is statically indeterminate .text on strenth of materials give methods of soving such problems. The design effort should be in keeping with the economics of a given situation , for example , if one line shaft supported by three or more bearings id needed , it probably would be cheaper to make conservative assumptions as to moments and design it as though it were determinate . the extra cost of an oversize shaft may be less than the extra cost of an elaborate design analysis.Another important aspect of shaft design is the method of directly connecting one shaft to another , this is accomplished by devices such as rigid and flexiable couplings.A coupling is a device for connecting the ends of adjacent shafts. In machine construction , couplings are used to effect a semipermanent connection between adjacent rotating shafts , the connection is permanent in the sense that it is not meant to be broken during the useful life of the machinem , but it can be broken and restored in an emergency or when worn parts are replaced.There are several types of shaft couplings, their characteristics depend on the purpose for which they are used , if an exceptionally long shaft is required in a manufacturing plant or a propeller shaft on a ship , it is made in sections that are coupled together with rigid couplings. A common type of rigid coupling consists of two mating radial flanges that are attached by key driven hubs to the ends of adjacent shaft sections and bolted together through the flanges to form a rigid connection. Alignment of the connected shafts in usually effected by means of a rabbet joint on the face of the flanges.In connecting shafts belonging to separate device ( such as an electric motor and a gearbox),precise aligning of the shafts is difficult and a fkexible coupling is used . this coupling connects the shafts in such a way as to minimize the harmful effects of shafts misalignment of loads and to move freely(float) in the axial diection without interfering with one another . flexiable couplings can also serve to reduce the intensity of shock loads and vibrationstransmitted from one shaft to another .中文翻译机械运动和动力学运动学的基本目的是去设计一个机械零件的理想运动，然后再用数学的方法去描绘该零件的位置，速度和加速度，再运用这些参数来设计零件。
机械式的 英文作文
机械式的英文作文英文：Mechanical devices have been a part of our lives for centuries, and they continue to play a vital role in our daily routines. From the simple machines like the wheel and lever to the complex ones like automobiles and airplanes, mechanical devices have revolutionized the way we live.One of the advantages of mechanical devices is their reliability. They are designed to perform a specific function repeatedly without fail. For example, a clock is a mechanical device that tells time accurately and consistently. Similarly, a car engine is a mechanical device that provides power to the vehicle and keeps it running smoothly.Another advantage of mechanical devices is their ease of maintenance. Unlike electronic devices, mechanical devices can be repaired or replaced with simple tools andbasic knowledge. For instance, if a bicycle chain breaks,it can be easily replaced with a new one. On the other hand, if a computer motherboard fails, it requires specialized knowledge and equipment to fix it.Despite their advantages, mechanical devices also have their limitations. They are often bulky and require a lotof space to operate. For example, a steam engine requires a large boiler to produce steam, which takes up a lot of space. Additionally, mechanical devices are often noisy and produce vibrations, which can be unpleasant for some people.中文：机械装置已经成为我们生活中的一部分几个世纪了，它们继续在我们的日常生活中发挥着重要作用。
机械类英语论文翻译.doc
机械类英语论文翻译.doc轴承内径 bearing bore diameter轴承寿命 bearing life轴承套圈 bearing ring轴承外径 bearing outside diameter轴颈 journal轴瓦、轴承衬 bearing bush轴端挡圈 shaft end ring轴环 shaft collar轴肩 shaft shoulder轴角 shaft angle轴向 axial direction轴向齿廓 axial tooth profile轴向当量动载荷 dynamic equivalent axial load轴向当量静载荷 static equivalent axial load轴向基本额定动载荷 basic dynamic axial load rating轴向基本额定静载荷 basic static axial load rating 轴向接触轴承 axial contact bearing轴向平面 axial plane轴向游隙 axial internal clearance轴向载荷 axial load轴向载荷系数 axial load factor轴向分力 axial thrust load主动件 driving link主动齿轮 driving gear主动带轮 driving pulley转动导杆机构 whitworth mechanism转动副 revolute (turning) pair转速 swiveling speed rotating speed转动关节 revolute joint转轴 revolving shaft转子 rotor转子平衡 balance of rotor装配条件 assembly condition锥齿轮 bevel gear锥顶 common apex of cone锥距 cone distance锥轮 bevel pulley; bevel wheel锥齿轮的当量直齿轮 equivalent spur gear of the bevel gear 锥面包络圆柱蜗杆 milled helicoids worm准双曲面齿轮 hypoid gear子程序 subroutine子机构 sub-mechanism自动化 automation自锁 self-locking自锁条件 condition of self-locking自由度 degree of freedom, mobility。
《机械外文翻译文献翻译液压传动》
英文原文Hydraulic SystemHydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdo m in 1795 • Braman Joseph (Joseph Braman ,1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved.Hydraulic transmission There are many outstanding advantages, it is widely used, such as general industr- ial use of plastics processing machinery, the pressure of machinery, machine tools, etc.; operating machinery engineering machinery, construction machinery, agricultural machinery, automobiles, etc.; iron and steel indu- stry metallurgical machinery, lifting equipment, such as roller adjustment device; civil water projects with flo- od control and dam gate devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power plant installations, nuclear power plants, etc.; ship from the deck heavy machinery (winch), the bow doors, bulkhead valve, stern thruster, etc.; special antenna technology giant with control devices, measu- rement buoys, movements such as rotating stage; military-industrial control devices used in artillery, ship anti- rolling devices, aircraft simulation, aircraft retractable landing gear and rudder control devices and other devi- ces.A complete hydraulic system consists of five parts, namely, power components, the implementation of co- mponents, control components, auxiliary components and hydraulic oil.The role of dynamic components of the original motive fluid into mechanical energy to the pressure that the hydraulic system of pumps, it is to power the entire hydraulic system. The structure of the form of hydra- ulic pump gears are generally pump, vane pump and piston pump.Implementation of components (such as hydraulic cylinders and hydraulic motors) which is the pressure of the liquid can be converted to mechanical energy to drive the load for a straight line reciprocating movement or rotational movement.Control components (that is, the various hydraulic valves) in the hydraulic system to control and regulate the pressure of liquid, flow rate and direction. According to the different control functions, hydraulic pressure control valve can be divided into valves, flow control valves and directional control valve. Pressure control valves are divided into benefits flow valve (safety valve), pressure relief valve, sequence valve, pressure relays, etc.; flow control valves including throttle, adjusting the valves, flow diversion valve sets, etc.; directional control valve includes a one-way valve , one-way fluid control valve, shuttle valve, valve and so on. Under the control of different ways, can be divided into the hydraulic valve control switch valve, control valve and set the value of the ratio control valve.Auxiliary components, including fuel tanks, oil filters, tubing and pipe joints, seals, pressure gauge, oil level, such as oil dollars.Hydraulic oil in the hydraulic system is the work of the energy transfer medium, there are a variety of mineral oil, emulsion oil hydraulic molding Hop categories.The role of the hydraulic system is to help humanity work. Mainly by the implementation of components to rotate or pressure into a reciprocating motion.Hydraulic system and hydraulic power control signal is composed of two parts, the signal control of some parts of the hydraulic power used to drive the control valve movement.Part of the hydraulic power means that the circuit diagram used to show the different functions of the interrelationship between components. Containing the source of hydraulic pump, hydraulic motor and auxiliary components; hydraulic control part contains a variety of control valves, used to control the flow of oil, pressure and direction; operative or hydraulic cylinder with hydraulic motors, according to the actual requirements of their choice.In the analysis and design of the actual task, the general block diagram shows the actual operation of equi - pment. Hollow arrow indicates the signal flow, while the solid arrows that energy flow.Basic hydraulic circuit of the action sequence - Control components (two four-way valve) and the spring to reset for the implementation of components (double-acting hydraulic cylinder), as well as the extending and retracting the relief valve opened and closed . For the implementation of components and control components, presentations are based on the corresponding circuit diagram symbols, it also introduced ready made circuit diagram symbols.Working principle of the system, you can turn on all circuits to code. If the first implementation of components numbered 0, the control components associated with the identifier is 1. Out with the implementation of components corresponding to the identifier for the even components, then retracting and implementation of components corresponding to the identifier for the odd components. Hydraulic circuit carried out not only to deal with numbers, but also to deal with the actual device ID, in order to detect system failures.DIN ISO1219-2 standard definition of the number of component composition, which includes the following four parts: device ID, circuit ID, component ID and component ID. The entire system if only one device, device number may be omitted.Practice, another way is to code all of the hydraulic system components for numbers at this time, components and component code should be consistent with the list of numbers. This method is particularly applicable to complex hydraulic control system, each control loop are the corresponding number with the systemWith mechanical transmission, electrical transmission compared to the hydraulic drive has the following advantages:1, a variety of hydraulic components, can easily and flexibly to layout.2, light weight, small size, small inertia, fast response.3, to facilitate manipulation of control, enabling a wide range of stepless speed regulation (speed range of 2000:1).4, to achieve overload protection automatically.5, the general use of mineral oil as a working medium, the relative motion can be self-lubricating surface, long service life;6, it is easy to achieve linear motion /7, it is easy to achieve the automation of machines, when the joint control of the use of electro-hydraulic, not only can achieve a higher degree of process automation, and remote control can be achieved.The shortcomings of the hydraulic system:1, as a result of the resistance to fluid flow and leakage of the larger, so less efficient. If not handled properly, leakage is not only contaminated sites, but also may cause fire and explosion.2, vulnerable performance as a result of the impact of temperature change, it would be inappropriate in the high or low temperature conditions.3, the manufacture of precision hydraulic components require a higher, more expensive and hence the price. 4, due to the leakage of liquid medium and the compressibility and can not be strictly the transmission ratio. 5, hydraulic transmission is not easy to find out the reasons for failure; the use and maintenance requirements for a higher level of technology.In the hydraulic system and its system, the sealing device to prevent leakage of the work of media within and outside the dust and the intrusion of foreign bodies. Seals played the role of components, namely seals. Medium will result in leakage of waste, pollution and environmental machinery and even give rise to malfunctioning machinery and equipment for personal accident. Leakage within the hydraulic system will cause a sharp drop in volumetric efficiency, amounting to less than the required pressure, can not even work. Micro-invasive system of dust particles, can cause or exacerbate friction hydraulic component wear, and further lead to leakage.Therefore, seals and sealing device is an important hydraulic equipment components. The reliability of its机械专业中英文文献翻译work and life, is a measure of the hydraulic system an important indicator of good or bad. In addition to the closed space, are the use of seals, so that two adjacent coupling surface of the gap between the need to control the liquid can be sealed following the smallest gap. In the contact seal, pressed into self-seal-style and self-styled self-tight seal (ie, sealed lips) two.The three hydraulic system diseases1, as a result of heat transmission medium (hydraulic oil) in the flow velocity in various parts of the existence of different, resulting in the existence of a liquid within the internal friction of liquids and pipelines at the sam- e time there is friction between the inner wall, which are a result of hydraulic the reasons for the oil tempera- ture. Temperature will lead to increased internal and external leakage, reducing its mechanical efficiency. At the same time as a result of high temperature, hydraulic oil expansion will occur, resulting in increased com- pression, so that action can not be very good control of transmission. Solution: heat is the inherent characte -ristics of the hydraulic system, not only to minimize eradication. Use a good quality hydraulic oil, hydraulic piping arrangement should be avoided as far as possible the emergence of bend, the use of high-quality pipe and fittings, hydraulic valves, etc.2, the vibration of the vibration of the hydraulic system is also one of its malaise. As a result of hydraulic oil in the pipeline flow of high-speed impact and the control valve to open the closure of the impact of the process are the reasons for the vibration system. Strong vibration control action will cause the system to error, the system will also be some of the more sophisticated equipment error, resulting in system failures. Solutions: hydraulic pipe should be fixed to avoid sharp bends. To avoid frequent changes in flow direction, can not avoid damping measures should be doing a good job. The entire hydraulic system should have a good damping measures, while avoiding the external local oscillator on the system.3, the leakage of the hydraulic system leak into inside and outside the leakage leakage. Leakage refers to the process with the leak occurred in the system, such as hydraulic piston-cylinder on both sides of the leakage, the control valve spool and valve body, such as between the leakage. Although no internal leakage of hydra- ulic fluid loss, but due to leakage, the control of the established movements may be affected until the cause system failures. Outside means the occurrence of leakage in the system and the leakage between the external environment. Direct leakage of hydraulic oil into the environment, in addition to the system will affect the working environment, not enough pressure will cause the system to trigger a fault. Leakage into the enviro- nment of the hydraulic oil was also the danger of fire. Solution: the use of better quality seals to improve the machining accuracy of equipment.Another: the hydraulic system for the three diseases, it was summed up: "fever, with a father拉稀" (This is the summary of the northeast people). Hydraulic system for the lifts, excavators, pumping station, dynamic, crane, and so on large-scale industry, construction, factories, enterprises, as well as elevators, lifting platforms, Deng Axle industry and so on.Hydraulic components will be high-performance, high-quality, high reliability, the system sets the direction of development; to the low power, low noise, vibration, without leakage, as well as pollution control, water-based media applications to adapt to environmental requirements, such as the direction of development; the development of highly integrated high power density, intelligence, mechatronics and micro-light mini-hydraulic components; active use of new techniques, new materials and electronics, sensing and other high-tech.Hydraulic coupling to high-speed high-power and integrated development of hydraulic transmission equ- ipment, development of water hydraulic coupling medium speed and the field of automotive applications to develop hydraulic reducer, improve product reliability and working hours MTBF; hydraulic torque converter to the development of high-power products, parts and components to improve the manufacturing process tech -nology to improve reliability, promote computer-aided technology, the development of hydraulic torque con- verter and power shift transmission technology supporting the use of ; Clutch fluid viscosity should increase the quality of products, the formation of bulk to the high-power and high-speed direction.Pneumatic Industry:Products to small size, light weight, low power consumption, integrated portfolio of development, the implementation of the various types of components, compact structure, high positioning accuracy of the direction of development; pneumatic components and electronic technology, to the intelligent direction of development; component performance to high-speed, high-frequency, high-response, high-life, high temp- erature, high voltage direction, commonly used oil-free lubrication, application of new technology, new technology and new materials.(1)used high-pressure hydraulic components and the pressure of continuous work to reach 40Mpa, the maximum pressure to achieve instant 48Mpa;(2) diversification of regulation and control;(3) to further improve the regulation performance, increase the efficiency of the powertrain;(4) development and mechanical, hydraulic, power transmission of the composite portfolio adjustment gear;(5) development of energy saving, energy efficient system function;(6) to further reduce the noise;(7) Application of Hydraulic Cartridge V alves thread technology, compact structure, to reduce the oil spill Water-based hydraulic systemsWater-based hydraulic systems traditionally have been used in hot-metal areas of steel mills. The obvious advantage of water systems in these industries is their fire resistance. Water-based hydraulic systems also have obvious cost advantages over oil-based fluid. First, non-toxic, biodegradable synthetic additives for water cost $5 to $6 per gallon. One gallon of concentrate can make 20 gallons of a 5% solution, so the cost of water-based hydraulic fluid actually can be less than 30 cents per gallon.Considering the costs associated with preventing and cleaning up environmental contamination, water-based hydraulic systems hold the potential for tremendous cost savings at the plant level. Oil that has leaked already becomes a very important problem. It must be collected, properly contained. Water containing synthetic additives, however, can by dumped into plant effluent systems.Cost savings at the plant level don't stop at the lower cost of the fluid and its disposal. Because water-based hydraulic fluid consists of 10 parts water and one part synthetic additive, 5 gallons of additive mixes with water to make 100 gallons of water-based fluid. A 50gallon container is certainly easier to handle than two 55-gallon drums, so warehousing is simpler, cleaner, and less cluttered. Transportation costs also are lower.Other potential plant-wide savings include improved safety for workers because the water-based fluid is non-toxic as well as non-flammable. These attributes can reduce plant insurance rates. Spills cost less to clean up because granular absorbents or absorbent socks are unnecessary. Water is "hot" againThe oil embargo in the 1970s sparked interest in water-based fluids as a less-costly alternative to oils. Even the most expensive water additives became attractive when designers learned that one gallon of concentrate would make 20 gallons of fluid.As oil prices gradually dropped, so did interest in water-based hydraulics. In retrospect, interest in water-based fluids centered around their cost saving potential. Most designers lost interest when they discovered that they could not just change the fluid in their systems from oil to water without making other substantial changes. They then become reluctant to accept other "disadvantages" - read substantial changes - of switching over to water-based hydraulics.What were viewed as disadvantages were really different rules that apply to water-based hydraulic systems? Designers probably resisted learning more about water-based hydraulics because they were intimated by all the work required to lean about how to design a new system or retrofit an older system. By closing their minds to this different technology, they missed the many other advantages of water-based fluid beyond initial cost. Now that environmental concerns have added disposal costs to the price of hydraulic fluids, water-based hydraulics has again become a hot topic.Fighting freezeWater-based hydraulic systems do, of course, have limits to their applications. One limitation is the potential of freezing. This possibility is probably the most significant blockade to more widespread application of机械专业中英文文献翻译water-based systems, especially in the mobile equipment industry. Longwall mining is by far the largest sector of mobile equipment that has been able to take advantage of water-based systems. Temperatures underground do not approach the freezing point of water, and fire resistance is essential. Mobile and even marine equipment used in temperate climates could cash in one the advantages of water based systems, but there is no guarantee that such equipment always will be used in above-freezing temperatures.Nevertheless, adding an anti-freeze to a water-based fluid can depress its freezing temperature to well below 32°F. Ethylene glycol - used in automotive anti-freeze - is toxic and is not biodegradable, so its use for anti-freeze in water-based hydraulic fluid would defeat the environmental advantage water-based fluid has. There is an alternative. Propylene glycol is not toxic and is biodegradable. It costs more than ethylene glycol and is not quite as effective antifreeze, so it must be used in slightly higher concentrations. Two more techniques to reduce freezing potential are to keep fluid circulating continuously and use hose where practical. Sealing the systemTwo more perceived problems with water hydraulic systems are bacterial infestation and difficulty in maintain proper concentrations. Sealing the system from atmosphere can hold bacterial growth in check. Addition of an anti-bacterial agent to the fluid can have a lasting effect on preventing bacterial buildup if air is excluded from the system.A sealed reservoir eliminates another problem suffered by many hydraulic systems: water ingression. This addresses another misconception about water-based systems: water-based systems not sealed from the atmosphere must be closely monitored to ensure that the additive concentration stays within tolerance. That is because water evaporates from the reservoir more readily than the additive does. Consequently, water evaporation causes the additive concentration to increase. When new fluid is added to a system, samples of the existing fluid must be taken to determine the concentration of additive in solution. These results then reveal the ratio of additive to fluid that must be added so that fluid concentration is correct.With a system that seals fluid from the atmosphere, the evaporation problem is virtually eliminated. Fluid that escapes by leakage is a solution containing water and additive. Therefore, the quantity of fluid in the system changes, but concentration does not. System fluid is replen ished simply by adding a pre-mixed solution of water and additive to the reservoir.中文原文液压传动液压传动和气压传动称为流体传动，是根据17世纪帕斯卡提出的液体静压力传动原理而发展起来的一门新兴技术，1795年英国约瑟夫•布拉曼(Joseph Braman,1749-1814)，在伦敦用水作为工作介质，以水压机的形式将其应用于工业上，诞生了世界上第一台水压机。
现代的机械英文作文
现代的机械英文作文英文：Modern mechanical engineering is an exciting field that combines creativity, problem-solving skills, and technical expertise. As an engineer, I get to work on a wide variety of projects, from designing and testing new machines to improving existing ones. One of the most interesting aspects of modern mechanical engineering is the use of computer-aided design (CAD) software, which allows us to create 3D models of our designs and test them virtually before building them in the real world.Another exciting development in mechanical engineering is the use of robotics and automation. These technologies are revolutionizing the manufacturing industry, allowing us to produce goods more efficiently and with greater precision than ever before. For example, I recently worked on a project to design a robotic arm for a factory that produces electronic components. The arm was able to pick upand place components with incredible speed and accuracy, greatly increasing the factory's productivity.Of course, mechanical engineering is not just about designing and building machines. We also need to consider the environmental impact of our work and find ways to make our designs more sustainable. For example, I worked on a project to design a wind turbine that was more efficient and less noisy than existing models. By using advanced materials and optimizing the blade design, we were able to create a turbine that produced more energy while also reducing noise pollution.Overall, modern mechanical engineering is an exciting and constantly evolving field that offers endless opportunities for innovation and creativity.中文：现代机械工程是一个令人兴奋的领域，它结合了创造力、解决问题的能力和技术专业知识。
机械工程力学专业英语翻译
4 Overview of Engineering Mechanics（工程力学概况）(1) Ideally, however, every such item has been designed according to some set of “functional requirements” as perceived by the designers-that is, it has been designed so as to answer the question, “E xactly what function should it perform?” In the world of engineering, the major function frequently is to support some type of loading due to weight, inertia, pressure, etc. From the beams in our homes to the wings of an airplane, there must be an appropriate melding of materials, dimensions, and fastenings to produce structures that will perform their functions reliably for a reasonable cost over a reasonable lifetime.然而，在理想的情况下，每一件产品都是设计人员根据对某些“功能要求”的理解而设计出来的，也就是说，在设计过程中，应该回答这样的问题，即“它应该具有哪种确切的功能？”在工程领域，主要功能通常是承受由于重力，惯性力，压力等作用的一些类型的载荷。
从我们居住房屋的梁到飞机机翼，都必须有一个适当的材料，尺寸，在较合理地寿命基础上具有较合理地成本，并能可靠地完成其功能的产品结构连接的组合。
制造机械作文英文
制造机械作文英文英文：As a manufacturer of machinery, I have a lot of experience in this field. The process of making machinery involves many steps, from design to production to testing. Each step is important in ensuring that the final productis of high quality and meets the needs of the customer.Firstly, the design process is crucial in creating a machine that is both functional and efficient. This involves working closely with the customer to understand their specific needs and requirements. Once we have a clear understanding of what the customer wants, we can begin designing the machine. This may involve creating 3D models and prototypes to test the design before moving on to production.Next, the production process involves manufacturing the machine using high-quality materials and advancedtechnology. This requires skilled workers who are experienced in using machinery and tools to create the components of the machine. It also involves quality control measures to ensure that each component is made to the highest standards.Finally, the testing process is essential in ensuring that the machine is safe and effective. This involves rigorous testing to ensure that the machine meets all safety standards and is able to perform its intended function. We may also conduct field tests to ensure that the machine performs well under real-world conditions.Overall, making machinery is a complex process that requires a combination of design, production, and testing. By following these steps, we can create high-quality machines that meet the needs of our customers and exceed their expectations.中文：作为一名机械制造商，我在这个领域有丰富的经验。
机床——机械类外文文献翻译、中英文翻译
毕业设计(论文)外文资料翻译系部：专业：姓名：学号：外文出处：English For Electromechanical(用外文写)Engineering附件：1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文机床机床是用于切削金属的机器。
工业上使用的机床要数车床、钻床和铣床最为重要。
其它类型的金属切削机床在金属切削加工方面不及这三种机床应用广泛。
车床通常被称为所有类型机床的始祖。
为了进行车削，当工件旋转经过刀具时，车床用一把单刃刀具切除金属。
用车削可以加工各种圆柱型的工件，如：轴、齿轮坯、皮带轮和丝杠轴。
镗削加工可以用来扩大和精加工定位精度很高的孔。
钻削是由旋转的钻头完成的。
大多数金属的钻削由麻花钻来完成。
用来进行钻削加工的机床称为钻床。
铰孔和攻螺纹也归类为钻削过程。
铰孔是从已经钻好的孔上再切除少量的金属。
攻螺纹是在内孔上加工出螺纹，以使螺钉或螺栓旋进孔内。
铣削由旋转的、多切削刃的铣刀来完成。
铣刀有多种类型和尺寸。
有些铣刀只有两个切削刃，而有些则有多达三十或更多的切削刃。
铣刀根据使用的刀具不同能加工平面、斜面、沟槽、齿轮轮齿和其它外形轮廓。
牛头刨床和龙门刨床用单刃刀具来加工平面。
用牛头刨床进行加工时，刀具在机床上往复运动，而工件朝向刀具自动进给。
在用龙门刨床进行加工时，工件安装在工作台上，工作台往复经过刀具而切除金属。
工作台每完成一个行程刀具自动向工件进给一个小的进给量。
磨削利用磨粒来完成切削工作。
根据加工要求，磨削可分为精密磨削和非精密磨削。
精密磨削用于公差小和非常光洁的表面，非精密磨削用于在精度要求不高的地方切除多余的金属。
车床车床是用来从圆形工件表面切除金属的机床，工件安装在车床的两个顶尖之间，并绕顶尖轴线旋转。
车削工件时，车刀沿着工件的旋转轴线平行移动或与工件的旋转轴线成一斜角移动，将工件表面的金属切除。
车刀的这种位移称为进给。
车刀装夹在刀架上，刀架则固定在溜板上。
溜板是使刀具沿所需方向进行进给的机构。
机械设计制造及其自动化毕业论文中英文资料外文翻译
机械设计创造及其自动化毕业论文外文文献翻译INTEGRATION OF MACHINERY译文题目专业机械设计创造及其自动化外文资料翻译INTEGRATION OF MACHINERY（From ELECTRICAL AND MACHINERY INDUSTRY）ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word： integration of machinery ，technology， present situation ，product t，echnique of manufacture ，trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management systemof by machinery for the characteristic integration ofdevelopment phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, of coveringtechnology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions,like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has the intellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneouscondition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stagewhich makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and the trend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Councilsummary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology developmenttrend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .Theartificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bedis to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the high performance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are various These question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out acondition .Imitate to living a manufacturing to belong to manufacturing science and life science of"the far good luck is miscellaneous to hand over", it will produce to the manufacturing industry for 21 centuries huge of influence .机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。
机械专业英语作文
机械专业英语作文Title: The Advancements and Applications of Robotics in Mechanical Engineering。
Introduction。
Mechanical engineering, as a field, has witnessed significant advancements in recent years, particularly in the realm of robotics. These advancements have not only revolutionized manufacturing processes but have also found applications in various other sectors. This essay explores the role of robotics in mechanical engineering, its evolution, current applications, and future prospects.Evolution of Robotics in Mechanical Engineering。
Robotics in mechanical engineering has evolved significantly over the past few decades. Initially, robots were primarily used in manufacturing industries for tasks such as welding, painting, and assembly line operations.However, with advancements in technology, robots have become more sophisticated and capable of performing complex tasks with precision and efficiency.The integration of artificial intelligence (AI) and machine learning algorithms has enabled robots to learn from experience, adapt to new situations, and make autonomous decisions. This has expanded the scope ofrobotic applications beyond traditional manufacturing settings to areas such as healthcare, agriculture, and space exploration.Current Applications of Robotics。
机械类外文文献翻译(中英文翻译)
机械类外文文献翻译(中英文翻译)英文原文Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the systemand then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that, if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available tous. These are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle [3].It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need, real or imagined. Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。
汽车制动系统(机械、车辆工程毕业论文英文文献及翻译)
Automobile Brake SystemThe braking system is the most important system in cars. If the brakes fail, the result can be disastrous. Brakes are actually energy conversion devices, which convert the kinetic energy (momentum) of the vehicle into thermal energy (heat).When stepping on the brakes, the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes.Two complete independent braking systems are used on the car. They are the service brake and the parking brake.The service brake acts to slow, stop, or hold the vehicle during normal driving. They are foot-operated by the driver depressing and releasing the brake pedal. The primary purpose of the brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by when a separate parking brake foot pedalor hand lever is set.The brake system is composed of the following basic components: the “master cylinder” which is located under the hood, and is directly connected to the brake pedal, converts driver foot’s mechanical pressure into hydraulic pressure. Steel “brake lines” and flexible “brake hoses” connect the master cylinder to the “slave cylinders” located at each wheel. Brake fluid, specially designed to work in extreme conditions, fills the system. “Shoes” and “pads” are pushed by the slave cylinders to contact the “drums” and “rotors” thus causing drag, which (hopefully) slows the car.The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder (Figure).Basically, all car brakes are friction brakes. When the driver applies the brake, the control device forces brake shoes, or pads, against the rotating brake drum or disks at wheel. Friction between the shoes or pads and the drums or disks then slows or stops the wheel so that the car is braked.In most modern brake systems (see Figure 15.1), there is a fluid-filled cylinder, called master cylinder, which contains two separate sections, there is a piston in each section and both pistons are connected to a brake pedal in the driver’s compartment. When the brake is pushed down, brake fluid is sent from the master cylinder to the wheels.At the wheels, the fluid pushes shoes, or pads, against revolving drums or disks. The friction between the stationary shoes, or pads, and the revolving drums or disks slows and stops them. This slows or stops the revolving wheels, which, in turn, slow or stop the car.The brake fluid reservoir is on top of the master cylinder. Most cars today have a transparent r reservoir so that you can see the level without opening the cover. The brake fluid level will drop slightly as the brake pads wear. This is a normal condition and no cause for concern. If the level drops noticeably over ashort period of time or goes down to about two thirds full, have your brakes checked as soon as possible. Keep the reservoir covered except for the amount of time you need to fill it and never leave a cam of brake fluid uncovered. Brake fluid must maintain a very high boiling point. Exposure to air will cause the fluid to absorb moisture which will lower that boiling point.The brake fluid travels from the master cylinder to the wheels through a series of steel tubes and reinforced rubber hoses. Rubber hoses are only used in places that require flexibility, such as at the front wheels, which move up and down as well as steer. The rest of the system uses non-corrosive seamless steel tubing with special fittings at all attachment points. If a steel line requires a repair, the best procedure is to replace the compete line. If this is not practical, a line can be repaired using special splice fittings that are made for brake system repair. You must never use copper tubing to repair a brake system. They are dangerous and illegal.Drum brakes, it consists of the brake drum, an expander, pull back springs, a stationary back plate, two shoes with friction linings, and anchor pins. The stationary back plate is secured to the flange of the axle housing or to the steering knuckle. The brake drum is mounted on the wheel hub. There is a clearance between the inner surface of the drum and the shoe lining. To apply brakes, the driver pushes pedal, the expander expands the shoes and presses them to the drum. Friction between the brake drum and the friction linings brakes the wheels and the vehicle stops. To releasebrakes, the driver release the pedal, the pull back spring retracts the shoes thus permitting free rotation of the wheels.Disk brakes, it has a metal disk instead of a drum. A flat shoe, or disk-brake pad, is located on each side of the disk. The shoes squeeze the rotatin g disk to stop the car. Fluid from the master cylinder forces the pistons to move in, toward the disk. This action pushes the friction pads tightly against the disk. The friction between the shoes and disk slows and stops it. This provides the braking action. Pistons are made of either plastic or metal. There are three general types of disk brakes. They are the floating-caliper type, the fixed-caliper type, and the sliding-caliper type. Floating-caliper and sliding-caliper disk brakes use a single piston. Fixed-caliper disk brakes have either two or four pistons.The brake system assemblies are actuated by mechanical, hydraulic or pneumatic devices. The mechanical leverage is used in the parking brakes fitted in all automobile. When the brake pedal is depressed, the rod pushes the piston of brake master cylinder which presses the fluid. The fluid flows through the pipelines to the power brake unit and then to the wheel cylinder. The fluid pressure expands the cylinder pistons thus pressing the shoes to the drum or disk. If the pedal is released, the piston returns to the initialposition, the pull back springs retract the shoes, the fluid is forced back to the master cylinder and braking ceases.The primary purpose of the parking brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by the driver when a separate parking braking hand lever is set. The hand brake is normally used when the car has already stopped. A lever is pulled and the rear brakes are approached and locked in the “on” position. The car may now be left without fear of its rolling away. When the driver wants to move the car again, he must press a button before the lever can be released. The hand brake must also be able to stop the car in the event of the foot brake failing. For this reason, it is separate from the foot brake uses cable or rods instead of the hydraulic system.Anti-lock Brake SystemAnti-lock brake systems make braking safer and more convenient, Anti-lock brake systems modulate brake system hydraulic pressure to prevent the brakes from locking and the tires from skidding on slippery pavement or during a panic stop.Anti-lock brake systems have been used on aircraft for years, and some domestic car were offered with an early form of anti-lock braking in late 1990’s. Recently, several automakers have introduced more sophisticated anti-lock system. Investigations in Europe, where anti-lock brakin g systems have been available for a decade, have led one manufacture to state that the number of traffic accidents could be reduced by seven and a half percent if all cars had anti-lock brakes. So some sources predict that all cars will offer anti-lock brakes to improve the safety of the car.Anti-lock systems modulate brake application force several times per second to hold the tires at a controlled amount of slip。
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用自动化机器翻译的指标来分析文章转化形式的影响Johann Roturier Linda MitchellSymantec Research Labs SALISBallycoolin Business Park Dublin City University Blanchardstown, Dublin 15, Ireland Ballymun, Dublin 9, Irelandjohann_roturier@ linda.mitchell7@mail.dcu.ie Robert Grabowski, Melanie SiegelAcrolinx GmbHFriedrichstr. 100, 10117 Berlin, Germany{robert.grabowski,melanie.siegel}@摘要本文研究的是当分析源转化形式对翻译机器的质量影响的同时，自动翻译器翻译的用户输入的内容的有用性，我们提出了一个新的框架，试图依靠自动检测，而不是人的判断，用来快速识别那些改善或降低质量的输出的改写规则。
我们发现，这种方法使我们能够快速识别两种语言之间的重叠规则（英语-法语和英语-德语）和某些具体情况下的规律精度还有待改进。
1引言软件出版商依靠手册和在线支持（知识库）的文章，以帮助他们的用户进行产品的安装，维护或排除故障。
随着Web2.0沟通渠道的出现，然而，这些文档集已经用用户生成衍生的内容（UGC）进行了补充。
现在，用户在相关软件产品内容的衍生上都非常活跃，尤其是在网上论坛，精明的用户在这里互相询问和交流问题以及解决方法。
虽然此类论坛特定语言版本有时会存在，大部分内容是很经常用英文写的，可能需要翻译成对任何用户都有用的。
然而这样的内容有时是机器翻译，一些理解问题可能存在。
这些目标端的理解问题可以被下列信息源端的UGC的特性所引起：源文章的内容可能会被写成非专业术语还是非母语（因此它的语言和技术的准确性可能不好）。
即使是书面语，这些有着正规的语法和词汇的创意的内容更接近口语部分。
文章的一些内容是由“技术精英的态度指导的，展现交流技术的（Leblanc , 2005），”有能力的用户所写的。
这些措施包括替代拼写，缩写，情况的变化，技术条款，表情符号，或者非词汇存在时的声音表示。
在本文中，我们提出了一个新的框架来快速评估具体再形成对机器翻译质量的影响。
该框架提供的再形成都与第2节提出的有一定的联系。
这项工作是在ACCEPT项目2范围内进行，其目的是使机器翻译适应新兴社区内容，使整个欧盟的公民更好地在商业和非营利性的社区环境访问。
2.相关的工作重写或重新组织文章源的内容，使之机器翻译的成为一个更加活跃的研究领域。
几种方法已被沿用到今天：源代码标准化，源代码重新排序和源代码控制。
我们的框架提供了一种方法来评估这些方法在快速方式方面的影响。
2.1资料来源规范化源标准化可以使用多种技术来实现，包括那些在Banerjee等人所述（2012年）：使用规律的表达，拼写检查和融合单词的分割。
尽管这些技术用来减少OOV的单词是有效的，然而当误差密度较低时，他们对于BLEU分数的改善的影响有局限性。
句子标准化的另一个领域涉及与相似的句子替换句子。
鉴于大量文本数据中，句子集群可以找到类似的句子，有利于规范他们。
如果变量选择在训练数据的翻译机器上受训，可以确信的是为了防止源语言文本的变化，这些改变在机器翻译的训练数据下100%的匹配。
这个问题在于，用户自己生成的内容不是那么均匀，导致有效地使用这个方法可能很困难。
2.2 源重新排序另一种方法是重新排序源文本，使其在得到机器翻译之前，更加接近目标文本。
这种方法是由Collins等人提出建议的（2005）和包括Genzel的补充（2010年）。
虽然这种方法可以使翻译质量改进（尤其是在BLEU得分方面），这是不恰当的，当转换后的源文本必须发布（这可能是在用户生成内容的背景的情况下）。
2.3源代码控制对词汇，语法和风格的限制或约束的源代码控制（或控制语言），为了提高机器译源文本，在技术创作的领域已经使用了很长时间的（Bernth和Gdaniec2002）。
多项研究，包括O’Brien and Roturier （2007）和Aikawa et al 等人（2007）已经表明，这种方法确实可以使机器翻译的质量改进（无论是在可理解性或后期编辑的效率计算）。
由于一些规则是系统的，域的或特定语言的，它们必须在被用于新的方案之前重新评估。
然而，这样的评估可能是非常耗时和昂贵的，特别是如果两套参考翻译是必需的（Doherty ，2012）。
因此在这项研究中，我们有兴趣找出，是否有可能依靠自动度量快速识别有效的规则，而不是通过人的判断。
3系统和数据的说明3.1 数据在本文中所使用的测试集包含的2031句子对应于从英语诺顿论坛随机选定的250个职位（如Banerjee等描述的，2012）。
这些集合，接着由专业翻译人员翻译成法国和德国的参考译文翻译。
然后，由专业评审来审查这些翻译的语言和技术，以识别和纠正潜在的翻译错误。
这次审查的结果被用来作为第二参考译文集。
3.2 MT系统在这些实验中使用的MT系统是以短语为基础的摩西系统，用标准的摩西流水线进行训练。
翻译和重新排序模型与所有可用的并行的串联数据进行了培训，然而对于其语言模型来说，每个单独的模型在各自语言库单独训练，并且所有模型都穿插在一起最大限度地减少对调整设置的难度。
摩西标记化和套管工具被使用。
并行数据包括赛门铁克的翻译记忆库数据（含产品说明书，营销内容，知识库的内容和网站内容），辅以Europarl的WMT123发布的新闻评论。
对于语言模型，所有并行数据的目标两侧分别使用，以及来自赛门铁克论坛的单语资料。
单语的数据不包括在英国和德国的系统，因为它被发现并非改善BLEU得分。
由论坛数据组成的调整和测试数据的赛门铁克系统（500平行的句子），已被有着网上机器翻译系统机器翻译，并使用CNLG/ TAUS指引编辑了。
3.3资料源变化系统AC-rolinx软件是建立在语言分析引擎上，提供有关单语文本的规则资源（如布雷顿坎普等人，2000所述），以及拼写，语法，风格和术语检查。
编辑前的这些方法可以在一方面作者被应用，因为通常在技术文档编写过程中完成的。
笔者的错误标记和改进建议，并重新改变其形式。
这个过程确保了文本转换始终是正确的。
此外，让笔者开始一个学习的过程。
他或她更好的理解机器翻译本身的能力和限度。
在另一方面，它能够自动适用于所提供的建议，重新进行翻译。
不同技术文件的创作支持，这里的重点是更好的机器翻译结果。
自动应用规则的要快得多。
这个过程仅影响翻译，因此该应用程序的精度不那么重要。
对于本文的目的，Acrolinx软件进行了调整，以处理用户生成内容，专门处理外来语言错误，接近口语的内容和使用的“技术人员”的语言。
我们用所谓的“autoApplyClient”的独立工具将文档发送到一个Acrolinx服务器，检索结果，并自动通过其建议更换文档的标记部分，然后应用所有建议重新拟订。
客户端具有两个不同的输出模式。
在第一种模式，它适用于将所有建议放到同一个文件，并将结果写入到一个新的（单一）文件。
在第二种模式下，单独应用建议：为每一个可能改写，客户端输出原句，改写句子，错误类型（拼写，语法，样式或术语），以及应用名称语法或样式规律，或者已经使用的术语的变异。
对于评估，我们使用全球化的和以句子为基础的改写模式。
3.4 使用自动度量的评分为了快速识别预先编辑那些，看起来对MT的翻译质量有改善或降低作用的改写类型，我们使用自动度量的得分，改写文本的原件和翻译方面的参考译文。
为了得到对整个文档影响的首次评估，我们计算了以下成绩：（Lin和Och，2004）所有句子的平均平滑BLEU，翻译错误率（TER等人在Snover的描述，2006）和一般文本匹配器（GTM，在梅拉梅德等刊物上的描述，2003），包括精度，调用和F值分数。
对于在句子级别基础上的影响的第二次评估，我们计算每重新变化和原句的下列项目的分数：平滑BLEU，翻译错误率（TER），和一般文本匹配器（GTM）F值。
BLEU的“平滑”修改避免成为零的情况，即得分是N-gram不存在，一种常见的情况是以小尺寸为参考的，以句子为基础的评估。
此外，我们计算了用于翻译系统训练集建立的语言模型（LM）的得分。
通过训练集，给LM分数分段。
LM分数，对于摩西是确定最有可能的翻译的一个因素。
在这里，我们计算了包括文章源和目标语言训练集的LM得分，以下是两个假设：1.更好的源语言模型得分使得文本更“容易”进行翻译，因为它更类似于训练语言。
2.一个更好的目标语言模型的评分，意味着类似的目标语言的句子是“已经了解”语句，因而具有较高的翻译质量。
为了轻松获得评分结果，我们创建了一个结合了autoApplyClient，摩西SMT软件，以及不同的自动评分指标的框架，如图1图1：规则评估框架第二个实验侧重于每个单独重新变化的句子的分数。
因为绝对值在不同的指标和句子之间不具有可比性，我们简化了数据集的转换相对分数:对于每个重新组合的句子中，我们注意到得分相对于不重新配方的对应的原句分数是否有所改善，降级或保持不变。
注意，在分数方面影响的“量”不予考虑。
3.5 用于人类改革的分数在第二个实验中，有两个因素无疑是代表损害性结果的。
首先，在句子层面计算分数意味着小“错误判断”通过自动度量平整数据的大小检测不出。
其次，切换到一个相对更好的/等于/差的指标意味着改写的影响量的信息将丢失。
为消除这些影响，并对自动度量有一个更好地理解，我们首先过滤掉，对给定输入数据的改变不超过12个的所有规则。
对于其余规则的再形成，我们再进行人工评估。
评估者给予初始句子和改写句子的翻译，来判断哪个转换为更接近参考译文，或是否存在变化。
这个过程因此给另一组成绩好/等于/坏的规模。
有了这个“人指标”，我们能够检查自动度量是否与人的判断一致，在此之前，我们看基于自动计算分数的有巨大影响力的特定的规则。
4 自动改定实验及结果我们进行了两组实验：第一种包括对整个测试集自动重新拟订的。
第二轮实验中研究了个体建议水平上的分数。
4.1总体结果表1表示由自动应用客户端和源文本之间的差异量（以TER和GTM F值计算）改变句子（满分2031）数量：(in terms ofTER andGTMF-Measure):SentsTER GTM F-MeasureOriginal vs.Spelling150 0.0101 0.9804Original vs.Gram-mar67 0.0054 0.9901Original vs.Style328 0.0334 0.9529Original vs.Spelling+Grammar197 0.0157 0.9708Original vs.Spelling +Grammar +Style403 0.0483 0.9279表1：文本源的变化表1表面了语法重新配方（67）远没有拼写（150）或类型变化的频繁。