A Design Rule for Inset-fed Rectangular Microstrip Patch Antenna
英语作文-揭秘集成电路设计中的设计规则与布局约束
英语作文-揭秘集成电路设计中的设计规则与布局约束Integrated circuit (IC) design is a complex process that involves various design rules and layout constraints. In this article, we will delve into the secrets of IC design and explore the key considerations in designing and laying out integrated circuits.To begin with, one of the fundamental design rules in IC design is the minimum feature size. This refers to the smallest dimension that can be reliably manufactured on a chip. As technology advances, the minimum feature size decreases, allowing for more transistors to be packed onto a single chip. Designers must adhere to these rules to ensure the manufacturability and functionality of the IC.Another important design rule is the spacing between different components on the chip. This is known as the minimum spacing rule and ensures that there is sufficient isolation between adjacent components. Violating this rule can lead to interference and crosstalk, which can severely impact the performance of the IC. Designers must carefully consider the spacing requirements and optimize the layout to minimize any potential issues.Furthermore, the design of power distribution networks is crucial in IC design. Efficient power delivery is essential to ensure the proper functioning of the circuitry. Designers must consider factors such as voltage drop, current density, and thermal management when designing the power distribution network. By carefully analyzing and optimizing the power delivery system, designers can enhance the overall performance and reliability of the IC.In addition to design rules, layout constraints play a vital role in IC design. One such constraint is the placement of components on the chip. Proper component placement is essential to minimize signal delays and optimize the overall performance of the IC. Designers must consider factors such as signal integrity, power consumption, and thermal considerations when determining the optimal component placement.Another important layout constraint is the routing of interconnects. Interconnect routing refers to the process of connecting different components on the chip using metal traces. Designers must carefully plan and optimize the routing to minimize signal delays, reduce power consumption, and ensure proper signal integrity. Advanced routing algorithms and techniques are employed to achieve efficient and reliable interconnects.Moreover, the consideration of design for manufacturing (DFM) rules is crucial in IC design. DFM rules ensure that the design can be manufactured with high yield and reliability. Designers must consider factors such as lithography constraints, process variations, and mask alignment accuracy when designing the IC. By incorporating DFM rules into the design process, designers can minimize manufacturing issues and improve the overall yield of the IC.In conclusion, the design rules and layout constraints in integrated circuit design are essential for ensuring the manufacturability, functionality, and performance of the IC. Designers must carefully adhere to these rules and constraints while considering factors such as minimum feature size, component spacing, power distribution, component placement, interconnect routing, and design for manufacturing. By following these guidelines, designers can create efficient, reliable, and high-performance integrated circuits.。
定义设计规则(Defining Design Rules)
首页电子类软件教程PADS2007 系列教程正文第五节–定义设计规则(Defining Design Rules)发布日期：2009/1/2 15:39:25 来源：作者：点击：2294第五节–定义设计规则(Defining Design Rules)一旦你输入了网络和元件后，你就可以指定设计规则(Design Rules)和各层的定义(Layer Arrangements)。
包含安全间距(Clearance)、布线(Routing)和高速电路(High Speed)约束等等，这些规则分配作为默认(Default)的条件、类(Class)、网络(Nets)、组(Group)、管脚对(Pin Pairs)、封装(Decal)和元件(Components)；另外，你还可以设定指定条件的设计规则(Conditional Design Rules)和差分网络(DifferentialPairs)的规则。
本节将显示如何：· 设置PCB 各层的定义(Layer Arrangement)· 设置缺省的安全间距规则(Clearance Rules)· 设置网络的安全间距规则(Net Clearance Rules)· 设置条件规则(Conditional Rules)· 设置层的显示颜色(Layer Colors)在你继续之前，如果previewnet.pcb 设计文件还没有打开，打开它。
1. 从工具条中选择打开(Open)图标。
2. 当Save old file before reloading?提示出现后，选择No。
3. 在文件打开(File Open)对话框中，双击名为previewnet.pcb 的文件。
设置PCB 各层的定义(Layer Arrangement)PADS Layout 允许你定义PCB 的各层(Layer Arrangements)。
这包括指定层数(Number of Layers)、网络分配到一个平面层上、各层的介质定义(Layer Stackup 和厚度定义(Thickness)。
Quantum Sails Ensign Tuning Guide
Ensign Tuning GuideQuantum Sails has used our years of experience building and racing Ensign sails to develop a fast set of Class sails, geared for performance in all racing conditions. Together with the industry’s most rigorous quality standards of Cloth Selection, Cutting Accuracy, and Craftsmanship, we have created a unique combination of speed, quality, and long lasting performance sails.We hope this guide will help you take your Ensign campaign all the way to the Grand Prix level. We believe that a successful racing campaign is a combination of many elements. While one of the most dramatic improvements to any Ensign is a new suit of Quantum sails, we cannot over emphasize the importance of raising the level of all the other components of your campaign to that of your new Quantum sails.Before Your Boat Hits The WaterClean and sand your bottom to 600 finish, flattening any bumps. It is important to make sure to keep your bilge as dry as possible at all times, especially before the boat is put away for the offseason. There is a fiberglass shell surrounding the Lead Ballast of your keel. Water will seep into this area and contract and expand in the heat or freezing cold respectively, cracking the shell. Cracks in the outer shell are slow, creating drag. Large cracks are potentially dangerous and should be brought to the attention of a professional boat shop.The other major reason for meticulous water concern is that the boats are constructed with a large amount of Balsa wood. Although lightweight, Balsa absorbs water quickly like a sponge and will aid in rot, especially in the deck and cabinhouse. The RudderThe Ensign Rules state the Rudder Specifications thoroughly. Before glassing the rudder please consult your rule book. We prefer the fiberglass rudders over wood ones for better performance. Fiberglass is easier to fair to the rules and will not absorb water as easily.RiggingWe recommend your set up your headstay close to the Ensign Class maximum length (26’ 3 3/4”). The best All-Purpose length is 26’3”. This allows you to set up the rig with the proper rake and prebend required for Quantum Ensign sails. Refer to our Trim/Tuning Chart for specifics on the shroud tensions. (below)Mast ButtWhere the mast butt is located is at the heart of rig tuning. Because mast step locations vary from boat to boat, we do not have a concrete measurement of where your own butt should be located. What you want to look for is 1 ½ - 2” of prebend in the mast when the uppers and forward lower shrouds are tensioned properly (~40/40 units) with the rig centered and the backstay hooked up and reading 0-5 units of measure on the tuning gauge (using the gauge on the forestay). We usually recommend shimming your mast forward at the deck, if there is room to do so. If you have less than 2” of prebend, un-screw the shrouds and move the butt aft a little, or forward a little if the mast has too much bend. Re-tension the rig. This is an important step and if you are not confident with the pre-bend amount repeat these steps until you see this 2” of pre-bend. I usually just sight up the mast when looking for this.See Chart Included to help locate your Mast Butt in the proper position (last page).Upwind SailingGet the crew dialed into the trim/tuning chart. By changing gears in the varying conditions, big gains can be made. The sails are very versatile. In the lulls, move trim to the lower breeze settings in the main and genoa. In the puffs, trim the genoa and main for speed. If over-powered, ease the traveler down to flatten the boat and relieve weather helm.The Quantum Mainsail gives lots of kick for pointing. By bringing the top batten to parallel and then to windward a few degrees, the boat will point 3-6︒ higher. When the boat slows in speed, change from “point” back to “speed” mode by easing the mainsheet and bringing the traveler up, keeping the boom in centerline of the boat. This versatility in the main is very desirable for squeezing off competition behind you and not getting sucked in to competition in front of you.The mainsail needs the sheet to be eased hard to fall off at the weather mark and during “Ducking” other boats on the beat.Set up the genoa leads for the prevailing breeze and then play the sheet through the puffs and lulls. Have the crew sit forward and to leeward in light air. Then move them to the benches as the boat speeds up around 7 knots of wind and more. In lighter air the Genoa will be about 3” off the spreader and just touching the shr ouds at the foot. As the wind build the foot should be pulled in tighter on the foot and still about 2 - 3” off the spreader. You will want to move the genoa lead car aft as the wind builds and this will aid in twisting the genoa and de-powering.Downwind SailingTry to keep the top batten parallel to the boom by adjusting the vang. In reaching under genoa, allow the main to twist similar to the genoas Leech. Trim the Pole just aft of square to the apparent wind in light/medium and medium to heavy breezes. In light air square the pole to 90︒, in drifters try the pole just forward of square.The spinnaker should be flown with the clews relatively even to having the guy slightly higher by 2 - 3”. The chute performs best with a 4 - 6” curl in the wi ndward leech shoulder. When reaching hard try pulling the pole down more, this will pull the draft of the chute forward and aid in turning the symmetric spinnaker into more of an asymmetric.Heel the boat to weather when running dead downwind in a moderate breeze. In lighter wind heel the boat according to the helm feel – usually flat to slight leeward heel.Try to steer the boat with the crew weight instead of the rudder downwind. You want to minimize the water flow disturbance past the rudder, minimizing drag. Move the crew to weather to go down or fall off, and move the crew to leeward to come up. Crew weight is most effective moving around in the middle and forward of the companionway.OverallGood Luck and feel free to contact us with any questions and input. We realize that the boats can be setup quite differently, so we have endeavored to provide simple, general numbers for you to shoot for. Have a great season.Doug Burtner Randy Shore Allen Terhune Terry Flynn585-342-5200 401-849-7700 410-268-1161 281-474-4168 dburtner@... rshore@... aterhune@... tflynn@...…@ENSIGN Trim & Tuning Chart***NOTE- The stays are 5/32” diameter, and we use “Loos Gauge” 91-model A (not B)。
版图培训第二讲_design rule
讲答：都可以下载到电脑上么？不行的话我发mail.美女1: 可以美女2:有中文版本的吗？讲答：没有讲答：并且所有的厂家提供的design rule都是英文版的美女3:表示英语太差伤不起啊讲答：没事，你看过几份design rule都就好了，大家用词跟在意的点是一样的。
美女3: 是不是都差不多的讲答：嗯美女3: 那就好讲答：并且里面有图指示，然后有的design rule允许copy整段用google翻译，有任何不明白的都可以问。
讲答：刚刚那份文件，1-5页都是讲的过去的版本信息，讲了分别更新了什么，大家可以不看，从第6页开始看。
讲答：第6页，表示文件号为：TD-MM18-DR-2003，这个是告诉你这个工艺文件是0.18 混合信号，1.8伏/5伏的制程的设计规则。
讲答：1.8v/5v的意思呢，是说这个工艺生产出来的device(器件)的耐压，有部分器件是工作在1.8v电源电压下，有部分器件是工作在5v电源电压下。
讲答：如果看到14页了跟我说一下，我给大家解说一下这些层。
讲答：对于14页，在Process Name这一列，就是讲了这个工艺提供的各个layer的命名。
讲答：里面的AA，描述说是active area/SDG，active就是有源区，也就是说我们资料里的DIFF，这个工艺给命名为AA。
讲答：NW --就是N阱，N-Well ，GT--就是poly 。
帅哥1: gt 是gate吗讲答：是的，gt就是gate帅哥1: DNW NW有啥不同？讲答：DNW是另外一个N-Well,解释说是深NWell，就是它往硅片里注入的深度更加的深，当然，掺杂浓度要比NWell浅，意思是NWell如果说是N-,那DNW可以理解为N--。
讲答：SN--nimp，n注入，SP-pimp,p注入，CT就是cont，讲答：DG 这一层，他给的描述是Dual Gate,就是这个意思，我们画nmos/pmos是有的会加上这一层，有的不加，不加这一层的mos的耐压（能够承受的电压）就是1.8v，加了这一层的mos的耐压就是5v，有这一层跟没有这一层，在foundry生产加工上是有区别的。
Ansys Nuhertz FilterSolutions 说明书
Ansys Nuhertz FilterSolutions Ansys Nuhertz FilterSolutions provides automated design, synthesis and optimization of RF, microwave and digital filters in an efficient and straightforward process. FilterSolutions starts with your filter performance specifications, synthesizes both ideal and physical filter layout realizations and automatically sets up filter analysis and optimization in the Ansys HFSS electromagnetic simulator.•Performing high-performance microwave and mmWave filter design is difficult and requires expertknowledge to synthesize filter layouts.•RF and microwave filters experience electromagnetic (EM) cross coupling, which leads to inaccuracies intraditional circuit modeling approaches. •Poor filter designs and manufacturing tolerances drivethe need for manual filter “tuning” by hand on the bench. A good CAE approach can create tuning free designs that work within manufacturing or material tolerances.•High-order filters are difficult to optimize, even with EM software. Creating an accurate first designprototype is essential for fast design optimization.Open the filter design in AnsysHFSS, ready for immediate EManalysis and optimization.Create digital filters in the form of filter tap coefficients and C-codefunctions./Targeting your top 4 pain points:/Achieving your top 4 tasks:Quickly, easily and automaticallysynthesize a filter that meets yourperformance requirement.Realize the filter design in schematic and physical layouts for your choice of substrates byharnessing vendor-specific partsand standard value components.Filter design in Ansys Nuhertz FilterSolutionsElectromagnetic simulation of synthesized filter in HFSS/W hat differentiates Ansys Nuhertz FilterSolutions? •Performance specification for Layout-to-EM-Optimization in a single smooth workflow•Ability to evaluate the widest range of filter topologies (Bessel, Butterworth, Chebyshev I and II, Elliptic, Gaussian, Delay, Hourglass, Legendre, Matched, Raised Cosine, Tubular, Zigzag, Coupled-Resonator and Cross-Coupled Folded Resonator)•Highly accurate distributed filter layout synthesis based on EM-derived model discontinuities and couplings•Integrates with HFSS for gold-standard EM analysis accuracy and for EM-based optimization•Ability to synthesize filter topologies for analog and digital filter topologies; a single tool for creating accurate filters for both analog and digital signal processing (DSP) applications•Planar filter realizations in the widest available media classes (microstrip, stripline, asymmetric stripline, suspended substrate)/Ansys Nuhertz FilterSolutions provides automatic filter design for: •Lumped filters , presenting synthesized filter schematics that fulfill the filter performance specification. Also provides values for filters realized on PCBs with surface mount or thru-hole discrete components.•Distributed (transmission line filters) - High-performance distributed filters manufactured on microwave or mmWave substrates. These filters are usually realized with transmission lines, open or shorted stubs, vias, coupled lines and cross-coupled transmission line systems. A broad class of microwave and mmWave filters can be realized through precision patterning of conductors on one to three planar substrates.•Digital filters realized in software for digital signal processing (DSP) systems or on microcontrollers. These are software programs, applied to digital signal processing operating on data from digital sampling systems.•Zero-inductor analog filters - Popular at lower frequencies (audio and mid-frequency analog systems), these filters can be realized on PCB process technology with OpAmps in an analog filter format.•IC-based filters in the form of non-programmable digital filters can also be implemented in IC processes utilizing MOSFETS and capacitors to occupy minimum real estate and utilize a switched-capacitor approach.LUMPED (PASSIVE) FILTER MODULE Synthesizes a lumped component filter (single or double-termination) of a selected filter topology to realize user-specified performance characteristics. Standard value components may be applied, with standard (or non-standard) tolerance values for Monte-Carlo analysis. Components have ideal or finite Q or may be based upon vendor component library models.CAPABILITIESDISTRIBUTED FILTER MODULE The Distributed Filter module synthesizes filter layouts on physics-accurate materials, incorporating transmission lines and hybrid lumped elements. Filter layouts can be realized in a variety of substrate formats, including microstrip, suspended substrate and stripline. Physical layouts (including metallization and substrate material properties) can be realized quickly and accurately. Filter layouts are fully parameterized and may be opened in HFSS for immediate EM analysis; all geometries, materials, ports and analysis setups are automatically created. HFSS designs are fully parameterized and optimization setups are provided, so the designer can proceed directly to design optimization to desired response goals.ACTIVE FILTER MODULE Some filter designs call for elimination of inductors and active filter designs with OpAmps can sometimes provide an attractive alternative. The FilterSolutions Active Filter module synthesizes filters to meet user-specified performance requirements in a wide range of filter topologies, such as Thomas, Akerberg-Mossberg, Sallen-Key, Multiple Feedback, Leapfrog, GICs and more. Incorporate OpAmp models from your favorite vendor and include finite Q and gain effects in your active filter designs.SWITCHED-CAPACITOR FILTER MODULEAnother zero-inductor realization: Switched capacitor filters are generally realized in semiconductor processes where capacitors and switching transistors occupy comparatively small spaces. Switched-capacitor filters may be used to realize digital filters and involve sampling circuit topologies. The Switched-Capacitor Filter module synthesizes designs in IIR and FIR realizations, as well as Bilinear, Matched-Z, Step Invariant, Modified Impulse Invariant and custom Z-transform designs.ANSYS, Inc. *******************866.267.9724© 2021 ANSYS, Inc. All Rights Reserved.DISTRIBUTED FILTER DESIGN TOPOLOGIES Lumped Translation, Inductor Translation, Stepped Impedance, Shunt Stub Resonators, Open Stub Resonators, Spaced Stubs, Dual Resonators, Spaced Dual Resonators, Parallel Edge Coupled, Hairpin, Miniature Hairpin, Ring Resonator, Interdigital, ComblineACTIVE FILTER IMPLEMENTATIONS Thomas 1 and 2, Sallen & Key, Parallel, Akerberg, Multiple Feedback (MFB), GIC Biquad, GIC Ladder, Leap FrogDIGITAL FILTER DESIGNS BASED ON THE FOLLOWING DIGITAL TRANSFORMATIONSBilinear, Impulse Invariant (IIR), Matched Z, Step Invariant, FIR Approximation. FIR Filter Types: Rectangular, Bartlett, Hanning, Hamming, Blackman, Blackman-Harris, Kaiser, Dolph-Cheby, Remez, Raised Cosine, Root Raised Cosine, Cosine Filter, Sine Filter, Matched Filter, DelayFilter DIGITAL FILTER MODULE For DSP and sampled systems, FilterSolutions takes user-specified performance specifications and a desired topology and synthesizes filter coefficients to realize the digital filter. Digital transformations are provided to Bilinear, Impulse Invariant, Step Invariant, Matched-Z and Finite Impulse Response (FIR) approximation. Filter realizations are provided in the form of the discrete transfer function, filter tap/block coefficients or as C-code ready for incorporation into a DSP code block.ZMATCH MODULE Zmatch starts with complex load definitions and synthesizes a matching network for maximum power transfer. Includes both Discrete Frequency and Broadband Match modes. Optimal matching networks are provided in lumped, distributed and hybrid realizations.FILTER TYPES AVAILABLE (LUMPED AND DISTRIBUTED FILTERS)Gaussian, Bessel, Butterworth, Legendre, Chebyshev (I and II), Hourglass, Elliptic, Raised Cosine, Matched, Delay FILTER CLASSES AVAILABLE (LUMPED AND DISTRIBUTED FILTERS)Lumped Translation, Inductor Translation, Stepped Impedance, Shunt Stub Resonators, Open Stub Resonators, Spaced Stubs, Dual Resonators, Spaced Dual Resonators, Parallel Edge Coupled, Hairpin, Miniature Hairpin, Ring Resonator, Interdigital, Combline。
design-rule文件认知(一)6H
版图验证
DRC:对 IC 版图做几何空间检查，以确保线路能够被
特定加工工艺实现。 ERC:检查电源、地的短路，悬空器件和节点等电气 特性。 LVS:将版图与电路原理图做对比，以检查电路的连 接，与MOS的长宽值是否匹配。 LPE:从版图数据库提取电气参数（如MOS的W、L值 BJT、二极管的面积，周长，结点寄生电容等） 并以Hspice 网表方式表示电路。
Design—rule —
为什么layout engineer必须要了解 必须要了解design-rule? 为什么 必须要了解
画版图时需要按design rule的要求来操作，design rule是制造厂商根据 工艺，工厂设备，制作流程和水平等相关指标，设定出一个相符的规则，以 保证生产出的chip是有效的。 design rule与layout有很大的关系，有很多重复的劳动都是源自于design rule的upgrade（提升）。也就是在circuit不变的情况下，如果design rule有 变化，layout也要跟着变化（这里无形之中就增加了不少的工作量。） 所谓design rule有变化是指，同一家工厂的制程变化，在不同的工厂生 产等情况下，所造成的design rule的变化，但无论是何种原因引起的， layout总是要动手改的。所以，作为一个layout engineer是有必要对design rule有足够的了解的，并知道存在design rule的用意在何处。
Description Enclosure of P+ACTIVE >=
Rule 0.22um
Design—rule —
Extension Distance of inside edge to outside edge (EX)
Adaptive tracking control of uncertain MIMO nonlinear systems with input constraints
article
info
abstract
In this paper, adaptive tracking control is proposed for a class of uncertain multi-input and multi-output nonlinear systems with non-symmetric input constraints. The auxiliary design system is introduced to analyze the effect of input constraints, and its states are used to adaptive tracking control design. The spectral radius of the control coefficient matrix is used to relax the nonsingular assumption of the control coefficient matrix. Subsequently, the constrained adaptive control is presented, where command filters are adopted to implement the emulate of actuator physical constraints on the control law and virtual control laws and avoid the tedious analytic computations of time derivatives of virtual control laws in the backstepping procedure. Under the proposed control techniques, the closed-loop semi-global uniformly ultimate bounded stability is achieved via Lyapunov synthesis. Finally, simulation studies are presented to illustrate the effectiveness of the proposed adaptive tracking control. © 2011 Elsevier Ltd. All rights reserved.
德国工业设计大师-Dieter-Rams-的十条优秀设计准则
德国工业设计大师Dieter Rams 的十条优秀设计准则【1、优秀的设计应该是创新的。
Good design is innovative.】创新的可能性是永远存在并且不会消耗殆尽的。
科技日新月异的发展不断为创新设计提供了崭新的机会。
同时创新设计总是伴随着科技的进步而向前发展，永远不会完结。
It does not copy existing product forms, nor does it produce any kind of novelty for the sake of it. The essence of innovation must be clearly seen in all functions of a product. The possibilities in this respect are by no means exhausted. Technological development keeps offering new chances for innovative solutions.（TP 1 收音机/唱机组合, 1959,Dieter Rams为博朗公司设计）【2、优秀的设计让产品更加实用。
Good Design makes a product useful.】产品买来是要使用的。
至少要满足某些基本标准,，不但是功能，也要体现在用户的购买心里和产品的审美上。
优秀的设计强调实用性的同时也不能忽略其它方面，不然产品就会大打折扣。
A product is bought in order to be used. It must serve a defined purpose – in both primary and additional functions. The most important task of design is to optimise the utility of a product.（MPZ 21 multipress榨汁机, 1972,Dieter Rams and Jürgen Greubel为博朗公司设计）【3、优秀的设计是美的。
design rule
The BBC series shows—design rule, discusses 6 elements, namely space and planning, color, lighting, pattern and texture, and personality, that each of them plays a key role in a design perspective. I found this video is quite interesting and knowledgeable, because it is providing and explaining all the general concept for everyone who needed. Since it is quite impossible to cover all the material, I will more concentrate on the space and planning and color part instead.To begin with, everyone seems prefer huge room instead of a small one, but it is impossible to provide every single person to have a huge amount of space. And instead, it is even worse, with the population significantly increasing and the queasy GDP, having a reasonable space become a problem. Therefore, make the space “feel” bigger become to a severequestion. Fortunately, by applying couple design trick make this possible.In the video, the host, Laurence Llewelyn-Bowen, introduced several method to do so. The first and the most common trick is using color. Laurence introduced an easiest way to do it bychange everything to white which does giveus a feeling of “big”. We can simulate the scenario in our head simultaneously; think about a rectangle room with everything removed and colored in white, and then imagine you are standing at one end looking for another end, you will feel everything become blurred and significantly boundless. And the idea behind this is making the corner and side line as much as insignificant, because we will feel the area bigger if we don’t notice them to obvious. And another trick is use shape, i.e. horizontal or vertical line. This is quite easy to understand, horizontal line make room feel “longer”, whereas vertical make room wider.But why is it work? The science research indicates that even we are undergoing a three-dimensional space, but our eyes actually can only distinguish two-dimensional, namely length and width. But why we still can recognize height? It is because with our growing, our mind gathering the feeling and the information that delivered by our eyes, to form it into 3d space. So, it means cheating our eyes will blind our mind in order to make it feel lager by actually it is. But keeps in mind, the physical can never change, and that’s why we call it “trick”. But even though, it is still too ideal. Most of time, we won’t color EVERYTHING in white, because it also makes us feel bored. And we can’t remove every single thing since then the room itself become so meaningless as well. Therefore, even it is a good idea, but it is not applicable.So, we need another trick to accomplish this, which is the signature items. Every room has its own function, therefore, is must have some signature indicate it. For instance, a bedroom must have a bed, a washroom must have a sink, and a living usually have a TV. If you put a lot interrupt elements together, will make the room feel small either. Think about a situation such that, a TV and a radio and lots of children’s toy mix-up in a small room, you will feel everything is so tight and noisy, because no one will actually watch TV and listen music at same time. Therefore, to organize the room become important. Just recall the situation I described before, we can build a TV bench with drawers that can store those toys, and put the radio on a table beside the couch but not nearby the TV. In fact, the idea is to make something prominent, so others will become less apparent for you mind. But what if we still feel small?Fortunately, we have another way to do so—windows. There is a fact that the number of windows are increasing. Just go out and take a look, it is not hard to find that the number of window in a room become not only significantly more, but also dramatically huge. People tendto build the window more and large recently, and this tendency begin at late last centenary. Build a window will give your brain an intelligence that the room is not limited, but extend to outside. If cleaning the outside view or even more, ornament it as well will make us feel even bigger.To conclude, although we can’t physically make the room bigger, but by change the color, well-organization and a good view of a big French window can make your cozy room become much bigger mentally.In the series, there are a lot m ore method that I wasn’t mentioned is introduced as well, such how lightning could change our feeling in term of mood, how to arrange personalize custom could affect the overall looking and etc., beside Laurence is not just introduce and teach the way that every designer should have, but also explained why it works, and what it works for. Personally, I think the only thing not good about the series is the lacking of examples. But overall, it is a knowledgeable and interesting show and I strongly recommend everyone to watch it.。
集成电路设计专业名词解释汇总英文版
集成电路设计专业名词解释汇总英文版English:"Integrated Circuit (IC) Design: The process of creating a blueprint for the manufacturing of integrated circuits, such as microchips, using specialized software and tools. IC design involves several stages, including architectural design, logic design, circuit design, physical design, and verification. Architectural design establishes the high-level functionality and organization of the circuit, determining the overall structure and major components. Logic design involves the translation of the architectural design into a set of logic equations and functional blocks, specifying the logical operation of the circuit. Circuit design focuses on the actual implementation of the logic design, defining the electrical connections and components needed to achieve the desired functionality. Physical design, also known as layout design, involves the placement and routing of the components to ensure proper functioning and optimal performance, considering factors such as power consumption, signal integrity, and manufacturing constraints. Verification is the process of ensuring that the designed circuit meets the specified requirements and functions correctly under various conditions. Field-ProgrammableGate Array (FPGA): An integrated circuit that can be configured by the user after manufacturing. FPGAs contain an array of programmable logic blocks and interconnects, allowing for the implementation of various digital circuits. Hardware Description Language (HDL): A specialized programming language used to describe the behavior and structure of electronic circuits, facilitating the design and simulation of digital systems. Common HDLs include Verilog and VHDL. Electronic Design Automation (EDA) Tools: Software tools used in the design of electronic systems, including integrated circuits. EDA tools automate various stages of the design process, from schematic capture and simulation to layout and verification. Some popular EDA tools include Cadence Virtuoso, Synopsys Design Compiler, and Mentor Graphics Calibre. Very-Large-Scale Integration (VLSI): The process of integrating thousands or millions of transistors into a single chip. VLSI technology enables the creation of complex, high-performance integrated circuits, such as microprocessors and memory chips, by packing a large number of transistors into a small area. Application-Specific Integrated Circuit (ASIC): An integrated circuit customized for a particular application or purpose. Unlike FPGAs, ASICs are manufactured to perform a specific function, offering advantages in terms of performance,power consumption, and cost for mass production. ASIC design involves the development of custom circuitry optimized for a particular application, often using standard cell libraries and specialized design methodologies."中文翻译:"集成电路（IC）设计：是指利用专业软件和工具创建集成电路（如微芯片）制造的蓝图的过程。
IPD SE
IPD SEIntroductionIPD SE stands for Inter-Process Communication Design in Software Engineering. It refers to the design principles and practices employed when designing communication channels between different processes in a software system. Effective IPD SE is essential for ensuring seamless communication, coordination, and integration among various system components.Goals of IPD SEThe main goals of IPD SE are as follows:1.Reliability: IPD SE aims to establish reliable andfault-tolerant communication channels between processes.It ensures that messages are delivered accurately andefficiently, even in the presence of errors or failures.2.Efficiency: IPD SE focuses on designing efficientcommunication mechanisms that minimize latency andoverhead. This includes choosing appropriatecommunication protocols, minimizing message size, andoptimizing data serialization.3.Scalability: IPD SE must be scalable toaccommodate increasing demands as the system grows. It ensures that the communication architecture can handle a higher number of processes and increased message traffic without impacting performance.4.Flexibility: IPD SE allows for flexibility in choosingcommunication mechanisms and protocols. It shouldaccommodate different types of processes, such as client-server, peer-to-peer, or publish-subscribe architectures,and support different communication patterns, such assynchronous or asynchronous messaging.IPD SE Design PrinciplesTo achieve the goals mentioned above, the following design principles are commonly applied in IPD SE:1. Loose CouplingIPD SE encourages loose coupling between processes to enhance flexibility and maintainability. Loose coupling means minimizing dependencies between processes and allowing them to evolve independently. This is achieved by abstracting communication interfaces and protocols, using standardized message formats, and providing well-defined communication APIs.2. Message-Oriented CommunicationIPD SE favors message-oriented communication rather than shared memory or direct function calls. Messages are the primary means of communication between processes, allowing them to exchange data and synchronize their actions. Message-oriented communication provides better encapsulation, decoupling, and fault tolerance.3. Clear Communication Semantics and ContractsIPD SE emphasizes the need for clear communication semantics and contracts. Processes should agree upon the format, structure, and content of messages exchanged. It includes defining the expected behavior of the sender and receiver, error handling mechanisms, and possible message decoders.4. Error Handling and Fault ToleranceIPD SE must handle errors and failures gracefully. It includes defining error codes, exception handling mechanisms, and recovery strategies in case of message loss or network failures. Error detection, reporting, and recovery mechanisms should be in place to ensure reliable communication.5. Security and AuthenticationIPD SE addresses security and authentication concerns by implementing secure communication protocols, encrypting messages, and verifying the authenticity of the sender and receiver. It prevents unauthorized access, tampering, and interception of sensitive data.6. Performance OptimizationIPD SE considers performance optimization by minimizing message size, reducing network overhead, and optimizing message serialization and deserialization. It also involves adopting efficient communication protocols, such as UDP or TCP/IP, based on the system requirements.ConclusionIPD SE plays a crucial role in designing effective communication channels between processes in a software system. By following the design principles discussed above, developers can achieve reliable, efficient, and scalable communication, enabling seamless coordination and integration among system components. Implementing IPD SE principles ensures that the system can handle increasing demands, adapt to changes, and provide a robust and flexible communication infrastructure.。
NEW COMMON DESIGN RULES FOR U-TUBE HEAT-EXCHANGERS IN ASME, CODAP and UPV CODES
In 1992 ASME and CODAP decided to reconcile their design rules devoted to tubesheet heatexchangers. This reconciliation has been extended to the draft European Standard for Unfired Pressure Vessel (UPV), as CEN/TC54 decided in 1993 to adopt CODAP tubesheet design rules. This reconciliation covers both the analytical aspect (same theoretical basis) and the editorial aspect (same notations, same tubesheet configurations, same design loading cases, same structure and presentation of the rules). For more details see paper from F. OSWEILLER (2000). This reconciliation applies to the three types of heat-exchangers : Fixed tubesheet heat-exchangers : ASME and CODAP use the same analytical approach, but CODAP ignores the unperforated tubesheet rim. Floating tubesheet heat-exchangers : both codes have adopted the fixed tubesheet approach to the case of floating tubesheets. U-tube tubesheet heat-exchangers : CODAP has adopted ASME rule. Six configurations of tubesheets are covered in ASME, CODAP and UPV rules, depending on their junction with the shell and the channel (see Figure 1). However, for U-tube tubesheets, the 1998 ASME edition covers only 4 of these 6 configurations where the tubesheet is : integral both sides (configuration a) gasketed both side (configuration d) integral on one side, gasketed the other side (configurations b and e) using 3 different analytical approaches. The purpose of this paper is to show the development of a new analytical treatment to cover these 3 cases in a more consistent and refined manner. This paper represents the views of the Special Working Group on Heat Transfer Equipment, the committee developing the tubesheet design rules in ASME Section VIII, Division 1, Appendix AA.
Jingwei_textile_machinery
Jingwei textile machinery:A variety of core equipment appeared at the exhibitionIntellectualization and sustainable develop-ment are still the mainstream trends of textile industry. ITMA 2023, a four-year textile machin-ery event, arrived as scheduled and to be held in Milan, Italy from June 8 to 14. This grand meeting will certainly give a strong impetus to "Trans-froming the World of Textiles".In ITMA 2023, Jingwei Textile Machinery Co., Ltd. introduces several exhibits, including JWF1590 spinning frame, JWF1217 carding machine and new-generation twisting machine K3501F connecting the whole process logistics system from spinning, twisting to weaving.JWF1590● The machine adopts complete section assembly, 8-spindle bottom roller, aluminum al loy joint roller seat, round beam, L-shaped s pindle rail, double air duct process cottonsuction, and active ring rail lifting.● Integrated design for main machine with am aximum 1824 spindles.● The steel belt type doffing system ensures stable operation of the convex plate andcontrol lable speed.● The suction negative pressure on both sides oft he headstock and endstock is balanced, andt he energy consumption of process suction is reduced by more than 30%.● The high-precision combination of middleframe and spindle rail can meet thehigh-speed spinning requirements of over 22000 rpm.● The fully electronic drafting system achievesindependent driving and linkage control ofthree bottom rollers.● The new rapid doffing technology reduces the doffing time to less than 2 minutes.● The intelligent spinning expert system provides customers with a convenient spinning experience.● It can be equipped with value-added modules such as centralized cotton picking and roving, spinning and winding unit.● The new industrial design gives a refreshing visual experience.66China Textile Copyright©博看网. All Rights Reserved.。
构型管理 英语作文
构型管理英语作文Configuration management is a critical aspect of any successful project, whether it's in the field of engineering, software development, or any other industry.It involves the process of identifying and controlling the configuration of a system, product, or service throughout its lifecycle. This ensures that the product or service meets the specified requirements and is consistent with its original design.In today's fast-paced and dynamic business environment, effective configuration management is more important than ever. With the rapid advancements in technology and the increasing complexity of products and services, it's essential for organizations to have a robust configuration management system in place to ensure that they can keep up with the changes and deliver high-quality products and services to their customers.One of the key benefits of configuration management isthat it helps organizations to maintain control over their products and services. By documenting and tracking changes to the configuration of a product or service, organizations can ensure that they have a clear understanding of its current state and can identify any deviations from the original design. This allows them to take corrective action and prevent any potential issues from arising.Another important benefit of configuration managementis that it helps to improve the quality of products and services. By ensuring that the configuration of a product or service is well-documented and controlled, organizations can minimize the risk of errors and defects, and candeliver products and services that meet the highest standards of quality. This not only enhances customer satisfaction but also helps to build a strong reputationfor the organization in the market.Furthermore, configuration management also plays a crucial role in facilitating collaboration and communication within an organization. By providing a centralized repository for all configuration-relatedinformation, organizations can ensure that all stakeholders have access to the latest information and can work together effectively to make informed decisions. This promotes transparency and accountability and helps to streamline the overall project management process.In conclusion, configuration management is a fundamental aspect of any successful project. It helps organizations to maintain control over their products and services, improve their quality, and facilitate collaboration and communication. By implementing a robust configuration management system, organizations can ensure that they can keep up with the changes and deliver high-quality products and services to their customers.。
fr-iqa 设计原则
fr-iqa 设计原则
FRIQA是一种软件设计原则，它代表的是：
F - 封闭原则(The Closed Principle)：软件中的类应该对扩展开放，对修改关闭。
这意味着应该通过添加新的代码来扩展功能，而不是修改现有的代码。
R - 重用原则(The Reuse Principle)：软件中的可重用性应该是优先考虑的。
通过将代码组织为可重用的模块、组件或类，可以提高代码的复用度，减少重复编写相似功能的代码。
I - 接口分离原则(The Interface Segregation Principle)：应该根据使用的客户端的需求来划分接口，而不是设计一个庞大臃肿的接口。
通过保持接口的粒度小和单一职责原则，可以使系统更易于维护和扩展。
Q - 依赖倒置原则(The Dependency Inversion Principle)：高层模块不应该依赖低层模块，两者都应该依赖于抽象。
这种原则强调了面向接口编程的重要性，通过使用依赖注入等技术，可以降低类之间的耦合度。
A - 好处（Advantage）：遵循FRIQA原则可以提高软件的可维护性、可扩展性和可重用性，使代码更加灵活和易于测试。
因此，在软件设计中遵循FRIQA原则可以帮助开发人员构建高质量的软件系统。
构型管理英语作文
构型管理英语作文In the realm of engineering and project management, configuration management (CM) plays a pivotal role in ensuring the success and efficiency of complex systems. This essay aims to delve into the importance of CM, its key principles, and its applications in various industries.Firstly, configuration management is the process of establishing and maintaining consistency of a system's configuration throughout its life cycle. It involves identifying the configuration items (CIs) at the outset, controlling changes to these items, and recording the evolution of the system's configuration.The importance of CM cannot be overstated. It helps in maintaining the integrity of a product by ensuring that all components work together as intended. It also facilitates effective communication among team members by providing a clear and consistent view of the system's current state.There are several key principles that underpin CM:1. Identification: The process of identifying the configuration items that make up a system is crucial. Each CI must be uniquely identifiable to track changes and manage versions effectively.2. Control: Changes to the system's configuration must becontrolled to prevent unauthorized or untested modifications that could compromise the system's performance.3. Status Accounting: Keeping a detailed account of the configuration status is essential for understanding the current state of the system and for planning future changes.4. Audit and Review: Regular audits and reviews ensure that the configuration management process is adhered to and that the system's configuration remains accurate and up-to-date.Configuration management is applied across a spectrum of industries. In the software industry, CM is vital for version control and release management. In aerospace, it ensures that aircraft systems are maintained and upgraded correctly. In construction, it helps manage the design and build process to avoid costly mistakes.Moreover, CM is not just limited to physical products. It is equally important in managing digital assets, such as databases and web applications, where changes can have widespread impacts.In conclusion, configuration management is a critical discipline that ensures the stability, reliability, and maintainability of complex systems. By adhering to its principles and applying its practices, organizations can significantly reduce risks, improve efficiency, and enhance the quality of their products and services. As technology continues to evolve, the role of CM is likely to grow inimportance, making it an essential skill for professionals in various fields.。
Standard_electronic
Extended Design Rule Checking RuleDocument Status: Released Revision:1Author: Gary Leedberg Date:99-05-27Last Editor: Jeff Larason On: 2005-09-13Description:All PCB designs created in PADS must use the extended Rules Set to automatically verify that Regulatory and typical DRC spacing requirements are maintained.Note: The Design Rules may be directly entered in PADS or entered into ViewDraw and then imported to PADS.Refer to APC Design Standards #27 & #68, as well as IPC-2221 Table 6-1 for spacing requirements. Verification:The PCB design dB may be inspected to verify that Design Rule Checking parameters have been set for Regulatory and Standard validation.In the past, Regulatory spacing checks were conducted manuall y due to the design tool’s inability to validate multiple spacing requirements.Today, APC’s current PCB design tool PADS offers an intelligent Design Rule Checking option called Extended Rules. This option allows the designer to create multiple spacing rules which can be defined as default, class, net, group, pin pair, conditional, or differential pair. In short, Extended Rules allows the designer to automatically verify Regulatory requirements as well as typical DRC spacing.Although manual checks have been mostly successful, human error has allowed some spacing errors to make their way into APC product. To further ensure product quality and conformance, we must utilize the Extended Rules capability in conjunction with the manual checking process.UPS Over-voltage Immunity RuleDocument Status: Released - Change Pending Revision:1Author: Colin Campbell Date:97-05-09Last Editor: Rao Kondala On: 2005-06-07Description:The UPS must withstand sustained power frequency over-voltage and pass DC hi-pot values given in the following table.100V systemsMode Withstand voltage DC Hi-pot voltageLine - Neutral 200 V n/aLine - Ground 200 V 500 VdcNeutral - Ground 200 V 500 Vdc120V systemsMode Withstand voltage DC Hi-pot voltageLine - Neutral 250 V n/aLine - Ground 250 V n/aNeutral - Ground 250 V n/a200V systemsMode Withstand voltage DC Hi-pot voltageLine - Line 250 V n/aLine - Ground 250 V 500 Vdc208V systemsMode Withstand voltage DC Hi-pot voltageLine - Line 300 V n/aLine - Ground 300 V n/a220-240V systemsMode Withstand voltage DC Hi-pot voltageLine - Line 350 V n/aLine - Ground 350 V n/an/a: not applicableVerification:Verification of withstand tests:The Line-Neutral or Line-Line of the unit under test are connected to an AC source current limited to 10 Arms and set to nominal utility voltage. The AC source is commanded to output the Withstand test voltage at a slew rate of not less than 100V/s, where it shall remain for for 1 minute. Following the test the UPS shall display no permanent degradation in published specifications or failure to meet regulatory requirements.Perform the test under the following conditions:* unit ON and OFF* unit on-line, on-batteryVerification of DC Hi-pot test:The unit under test is off. Connect AC input leads together and connect to the (+) lead of a DC hi-pot tester set to trip at 150 uAdc, Connect the (-) lead to line cord Ground of the unit. Increase Hi-pot test voltage from 0 to 500 Vdc. Leave at the 500 Vdc setting for 10 seconds. The unit shall not cause the hi-pot tester to trip.1. 208 and 220-240V systemsField experience has shown that line-line connected MOVs having values 300V and lower are susceptible to damage from sustained power frequency over-voltage events on the mains. Such swell events are typically caused by improper mains transformer tap selection (already high mains voltage) concurrent with a sudden mains load dump. Note that the Withstand voltage does not account for very rare mains voltage wiring install mistakes where 1.73x or 2x voltage is presented to the UPS input.2. 120V systemsField experience and lab tests have shown that line-neutral and line-ground connected MOVs having values less than twice the nominal mains voltage are susceptible to damage from sustained power frequency over-voltage events on 120V mains. Such events are typically caused by:* improper mains transformer tap selection (already high mains voltage) concurrent with a sudden mains load dump* alternate phase ground fault causing ground voltage rise, worsened by high resistance ground path to junction box* high impedance or open neutral in installations where the neutral wire is shared between phases(120Y208 systems) - modular wired office partitions are famous for thisRMA analysis () has shown that 10% of all MOV failures in 120V SurgeArrest product (having 130V MOVs) are neutral-ground connected MOV failures. Any wiring fault that could result in N-G MOV over-dissipation will be detected first by the APC Site Wiring Fault indicator.3. 100V, 200V systemsIn Japan, whole buildings are subject to periodic DC hi-pot tests to ensure low leakage of building wiring and connected load equipment. The DC hi-pot voltage test is 500 Vdc. Products sold into Japan are required to have greater than 3 Mohms resistance from primary to ground (JEMA 1464).4. Compliance to the standard will avoidMOVs that are over-dissipated fail catastrophically and burst, emitting smoke and sometimes flames. The material emitted from an over-dissipated MOV is conductive, possibly causing unintended and dangerous leakage paths. The flames emitted from a catastrophically over-dissipated MOV will carbonize circuit board laminate, causing additional and possibly severe burning where all of the following conditions exist: * Line-line or line-ground traces are in proximity to each other and the MOV - this is obviously the case for line-connected MOVs. Lab tests show that proximity effects are within a 1" radius of the over-dissipated MOV.* The line current available to flow in a carbonized PCB is not limited to a value below 125 mA (this value per UL 1449 abnormal over-voltage test limit) or by an appropriately selected thermal line disconnect device.Provide space around the mounting holes of PCB with out any tracksin any layer to avoid Hi-Pot failure.Document Status: Released - Change Pending Revision:1Author: Suresh Subramanyam Date:2004-04-08Last Editor: Jeff Larason On: 2004-06-24Description:When designing a Printed Circuit Board sufficient clearance must be left around all metallic mounting points to insure the unit passes Hi-Pot testing. This includes all layers of the PCB. With the move toward higher density designs multi-layer circuit boards are being designed more and more frequently. The potential for failure during Hi-Pot testing has increased with this move to multi-layer boards. In order to lower this failure rate this standard governs the area that must be left clear or void of copper around metallic or conductive mounting hardware.When considering clearance spacing around metallic mounting hardware all the layers of a PCB will be considered as if they are external layers. The max outside diameter of any screw, washer or other metallic hardware will be used and considered case ground. All spacing will be measured from this max outside diameter and be considered all the way through the PCB as if the inside layers were the top layer. Spacing will be in accordance with Design Standard #27 Spacing for Power Circuits.Example of failure due to digging of spring / star washer which holds the PCB to the metal frame. :Exception:When using non-metallic, non-conductive mounting hardware this standard does not apply.When the mounting hole is used as an electrical connection such as the grounding of the circuit board this standard does not apply.Verification:As part of review all mounting holes of the PCB to be reviewed to ensure no tracks are under the mounting screw head for all layers of PCB.Unpackaged Mishandling ImmunityDocument Status: Released - Change Pending Revision:1Author: Fred Rodenhiser Date:2002-07-17Last Editor: On: 2004-12-22Description:Purpose:Unpackaged Mishandling Immunity is the ability of a product or product module to withstand the normal handling and accidental abuse it is likely to experience as part of its installation and use.A product or product module that meets this Design Standard demonstrates a minimum degree ofrobustness.Note: For the purpose of this standard, user installable or replaceable modules and finished products are referred to as "product".Business goals or requirements may at times dictate that the test requirement is not practical, desirable, or adequate. An alternate test series may be selected in such instances, however, this selection must be reviewed as specified by the New Product Development (NPD) process, and be adequately recorded in the appropriate database, (e.g, DVT), according to the practice of the group (SDG) and NPD process.Scope:The Standard covers an identifiable set of parameters, namely: drop heights and orientations. It is intended to specify a general set of mishandling conditions to which the products may beexposed to during installation and by accidental abuse while at an installation site. It is notintended as a substitute for responsible design practices or worst case (structural) analysis.The requirements specified herein are those in which the products will continue to function to the reliability statements of the product specification and will not, in any manner, expose anyindividual to a hazardous set of conditions. Products shall be exposed to at least two ascending drop heights, as listed in the table below under "Functional Drop" and "Safety Drop".All products shall remain safe and operational as defined by their functional specification following any single "Functional Drop" as described below. Cosmetic damage shall not be considered a failure of functionality. Exceptions to operability related to any user interface (i.e. switch, indicator, connector, etc.) shall be examined on a case by case basis..The product is not required to remain operational after a "Safety Drop" as described below. This test is intended to reveal potential hazardous conditions created by mechanical weaknesses in the products internal or external design. Hazardous conditions are determined by the application of regulatory standards normally applied to the product, where no standards exist refer to UL1778, section 7.2., section 8, section 11.Additionally, if upon reinstallation of the product into normal operating environment, hazardous conditions are said to exist if:Flame, burning oil, or molten metal is emitted from the enclosure of the product asevidenced by ignition, glowing, or charring of the cheesecloth or indicator paper;Cracking, rupturing, or bursting of the battery enclosure, or the enclosure of other energystorage devices, if such damage may result in user contact with hazardous chemicals;Explosion of the battery supply, or other energy storage device, if such explosion mayresult in a risk of injury to persons.Note: Testing may be performed on one or more units as deemed necessary by damage due to previous tests.Test SamplesProduct samples used for testing must be as representative of finished goods as possible. At a minimum, they must be mechanically accurate and fully functional. Prototype components may be used if they are not deemed to be of higher mechanical integrity than those expected in production. When practical, testing should be repeated when all production quality parts are available.Test Limits:Product Class (applicable to complete products or modules) ProductWeight,Kg (lbs)LargestDimensionFunctionalDrop Height,cm (in)Safety DropHeight,cm (in)DropClassMobile 0 to 4.5(0 to 10) NotApplicable100 (39) 122 (48) AStationary, manual handling, 1 person 0 to 22.7(0 to 50)Under 0.6meter30.5 (12) 76.2 (30) A0.6 meter orgreater30.5 (12) 76.2 (30) AStationary, manual handling, 2 or more persons 22.7 to 45.4(50 to 100)Under 1meter 22.9 (9.0) 76.2 (30) A1meter orgreater15.2 (6.0) 61.0 (24) AStationary, mechanical handling 45.4 to 113(100 to 250)15.2 (6.0) 61.0 (24) B113 to 227(250 to 500)15.2 (6.0) 45.7 (18) C227 (500)or greater15.2 (6.0) 45.7 (18) CDrop Class:A. Drop on each face, edge and corner; total of 26 drops.B. Drop on each corner; total of eight drops.C. Drop on each bottom edge; drop on bottom face or skid; total of 5 drops.Exception: Products of a weight greater than 45Kg (100lbs) which do not have capacity to store electrical or chemical energy shall not be required to comply with the requirements of the "Safety Drop".Product Toppling Requirements:Any product having an intended installation configuration of a "Tower", or having a height to width aspect ratio greater than or equal to 3 to1, shall be subjected to a "Toppling Drop". The product is not required to remain operational after a "Toppling Drop". This test is intended to reveal potential hazardous conditions created by mechanical weaknesses in the products internal or external design. Hazardous conditions are determined using the standard applied to the "Safety Drop".Related Industry Standards:IEC 68-2-31, Drop and Topple testing procedures:The objective of this test is to "assess the effects upon a specimen of simple standard tests intended to be representative of the knocks and jolts likely to occur during repair work or rough handling in use on a table or bench."IEC 68-2-32, Free Fall testing procedures:The objective of this test is to "assess the effects upon a specimen of simple standard tests intended to be representative of the fall likely to be experienced during rough handling, or to demonstrate a minimum degree of robustness, for the purpose of assessing safety requirements." This procedure encompasses single and repeated falls from heights of 25 mm, 50 mm, 100 mm, 250 mm, 500 mm, and 1000 mm.Verification:Drops shall be made from a quick-release device, drop test machine, or utilizing other methods which allow the product to fall freely and impact on the intended surface, edge, or corner.Test Equipment:Drop tester, solid wooden bench (4 cm thick minimum)Procedure:Sample status: Un-packagedFunctional Drop:Surface on which the product is to be dropped must provide a flat solid wooden bench (4 cm thick minimum).1. Drop the product from the specified height onto a face, edge, or corner.2. Inspect the product for physical damage, (inside and outside), then upon reinstallation andactivation of the product into rated nominal operating environment, inspect for electricalfunctionality and note any findings. (Note any damage which might cause a hazardous condition.)3. Repeat steps 1 and 2 for each drop as specified in the Drop Class column.Safety Drop:Surface on which the product is to be dropped must provide a flat, non-yielding base (tiledconcrete is acceptable if product weight is less than 70 lbs).1. Drop the product from the specified height onto a face, edge, or corner.2. Inspect the product for physical damage, (inside and outside), and note any findings.Specifically, be alert to:a. exposure of sharp edges,b. exposure of live metal parts,c. exposure of hazardous chemicals (e.g., battery electrolyte from a cracked battery),d. exposure to stored high energy source,e. disabling or damage to any product safety guard or interlock,f. internal safety spacing reduced to below required distances.3. Repeat steps 1 and 2 for each drop as specified in the Drop Class column.Toppling Drop:Surface on which the product is to be dropped must provide a flat, non-yielding base (tiledconcrete is acceptable if product weight is less than 70 lbs).1. Fix the base of the product along the longest edge.2. Apply a force perpendicular to the top edge of the product diagonally opposed to the fixedbase edge. Such force shall be applied as is required to promote a free rotational fall, through a 90° angle.3. Inspect the product for physical damage, (inside and outside), then upon reinstallation andactivation of the product into rated nominal operating environment, inspect for electricalfunctionality and note any findings. Specifically, be alert to:a. exposure of sharp edges,b. exposure of live metal parts,c. exposure of hazardous chemicals (e.g., battery electrolyte from a cracked battery),d. exposure to stored high energy source,e. disabling or damage to any product safety guard or interlock,f. internal safety spacing reduced to below required distances.4. Repeat steps 1, 2, and 3 in such a manner as to rotate the product in a direction opposite tothe first drop.Report all findings according to the practice of the group (SDG) and NPD process.Acceptability of malfunction due to physical damage of relatively delicate interface devices (e.g, a switch, indicator, connector, etc.), shall be determined on a case-by-case basis by the Product Line Chief Engineer or CTO.It is expected that results from the Safety Drop test will very widely. Acceptability of any marginal result shall be the responsibility of the Product Line Chief Engineer or CTO.Testing is performed to confirm the ability of the unpackaged product to meet the rigors of the expected installation environment, increase reliability, and limit the likelihood of exposing the user to a hazardous condition in the event of accidental abuse. The testing seeks to provide acontrolled and repeatable method by which to evaluate product performance.APC Design Standard #107PCB Assembly Drawings RuleDocument Status: Released - Change Pending Revision:1Author: Peter Finn Date:2001-12-04Last Editor: On: 2004-06-17Description:Scope:This standard establishes requirements and other considerations for the documentation of PCB assemblies.Purpose:The purpose of this standard is to establish the general requirements for the preparation of drawings necessary to fully describe PCB assemblies and to define the use and life of the assembly drawing as it pertains to the release of a PCB.Document Requirements:The necessary PADS documents have been created and stored as part of the APC start files. They are located and stored with the APC released libraries. For older designs that did not incorporate these assembly layers before an ASC file had been provided at the same location. This file, assmlayers.asc can be imported into older designs with no implications to the design. The file contains only lines and text and will not effect the designs rules or settings.Reason for need:As a global company we need to be consistent in how we present information and what information we present to Manufacturing. In the past Manufacturing would create an MEI. This was done through conversations between Manufacturing and Engineering. As we have grown to a global company this type of communication has become cumbersome. Secondly with the recent downsizing, the manpower does not exist to create MEI's.With the demise of the MEI there is a void in our information flow from Engineering to Manufacturing. The assembly drawing is deigned to fill that void on the initial release of a board or a board revision.Board Release Requirements:An assembly drawing will be required as part of the standard release package needed for a 640-XXXX or 641-XXXX release. It will be an Acrobat PDF document. It will be stored as part of the Manufacturing zip file required by APC Design Standard #74 PCB Specification Standard and the PCB Revisions PCB Design template under step Draft 640- Part Specification Documentation Step.Life of Assembly Drawing:The Assembly Drawing is meant to convey information at the release of a board. It is not intended to live through the products life cycle. The Work Instruction created at the manufacturing location will maintain that responsibility. The Assembly Drawing is used only for the transfer of information to Manufacturing to facilitate the creation of the Work Instruction. To that end it does not and will not be maintained after the approval of the 640-XXXX spec. It will however be required at any revision of the board that requires a letter revision and new approval of the spec. That is every time the board is letter revised there will be a need for a revised Assembly Drawing but the Assembly drawing will not be updated every time the Work Instruction or BOM changes. In effect the drawing is used for the initial transfer of information and then Manufacturing takes over the control and responsibility of maintaining its own documentation.Drawing Requirements:Printed Board Assembly Drawings should include the following items as required:Location of all componentsComponent reference designationsComponent orientation and polarityStructural details when required for support and rigidity (stiffeners), etc.Marking requirementsLead forming (mounting length) requirements if special requirements are neededSoldering requirements, including solder pasteEnvelope reference dimensionsComponent mounting and spacing installation requirements if special requirements are neededSpecial solder plug or masking requirementsElectrostatic discharge protection requirements (special label or ESD symbol)Electrical test requirements (ATE)Eyelets and terminalsConformal coating requirementsMechanical hardware including latches and mounting hardware (TO-220 to heatsink)Cleanliness requirementsWorkmanship specificationsPrinted Board Assembly Drawings should NOT include the following items:Drawings showing stack-upsThe obviousInformation that is part of the standard manufacturing processFormat:The format of the document will be Acrobat PDF. A sample Assembly Drawing is attached below.General Concept:The general concept of this drawing is to convey assembly information to the assembly facility, be it an APC factory cell or an outside assembly house. The end resulting assembly should be the same no matter where the assembly is made. This document should include enough information to insure that no matter where the assembly is produced it will be done consistently and to the same levels of functionality. Through the use of text, drawings and arrows the drawing will convey any information needed to assist the assembler in locating and placing any parts not placed by machine on the assembly. The drawing will convey any information needed to attach mechanical parts to the assembly such as heatsinks, connectors, sill pads, polarized parts, cables, or any other part that may be facilitated by some additional information. An example of this would be three TO-220 transistors on the board. All three have heat sinks. One needs a sill pad for insulation. The assembly drawing would clearly call out which TO-220 and heatsink need the pad. This could be done with a combination of arrows and text labeling the component and describing the work to be done.Verification:Board Release review.As a global company we need to be consistent in how we present information and what information we present to Manufacturing. In the past Manufacturing would create an MEI. This was done through conversations between Manufacturing and Engineering. As we have grown to a global company this type of communication has become cumbersome. Secondly with the recent downsizing, the manpower does not exist to create MEI's.With the demise of the MEI there is a void in our information flow from Engineering to Manufacturing. The assembly drawing is deigned to fill that void on the initial release of a board or a board revision.Inrush current RuleDocument Status: Released Revision:1Author: Neil Rasmussen Date:97-11-12Last Editor: On: 2002-08-08Description:Products shall be designed to limit inrush current to values compatible with expected AC circuit breakers in the user's power system.Exception: equipment which has an input current rating of less than 10% of the line current rating are exempted from the requirements to test under this rule. Note: Some products present an inrush that consists of both internally generated currents and currents caused by a load. An example could be an isolation transformer or a line interactive UPS. In these cases it is the combination of these currents which may cause a breaker trip. For this reason it is required to perform this test under load. The input current of the equipment for the purposes of this exception is the input current with the expected rated load.Exception: equipment that does not have transformers or other parts that create inrush current are exempted from the requirements to test under this rule. Determination by inspection.Exception: a product that carries special instructions requiring a special type of user circuit breaker may be tested with that breaker instead of a typical breaker. The product must have explicit instructions for the installer.Verification:The products shall be tested under all startup and operational conditions with an real utility AC source with an impedance as low as can practially be obtained as close to the lab AC service entrance as possible, using the expected circuit breaker. The product shall be loaded to full load (for products that carry a load). The load shall be a typical design load for the product. The peak current waveforms shall be monitored. The test shall be repeated 100 times.The circuit breaker shall not trip, nor shall the current exhibit a I-squared-T rating within the breaker's potential trip zone. At this time there is no standard breaker identified under this standard, so engineering judgement must be used in the selection of the breaker.During startup or utility transients, products may draw large inrush currents. Toroidal transformers, large steel transformers, and capacitor input converters are the main contributors.Battery spacing for high voltage RuleDocument Status: Released Revision:1Author: Neil Rasmussen Date:2000-10-10Last Editor: On: 2002-08-08Description:Insulation of batteries of over 250 volts: Cells shall be installed in groups having a total nominal voltage of not over 250 volts. Insulation, which can be air, shall be provided between groups and shall have a minimum separation between live battery parts of opposite polarity of 2 inch for battery voltages not exceeding 600 volts.Verification:Inspection.This is a National Electrical Code (NEC) requirement 480-6Loss of Phase/Neutral in 3 Phase systems RuleDocument Status: Released Revision:1Author: Mike Falcinelli Date:99-02-09Last Editor: On: 2002-08-08Description:3 phase products will be designed such that they can withstand the loss of any phase or neutral on the input, without damage to themselves or their load. Designs which disconnect from the line, and result in transfer to battery are acceptable solution. Return to on-line condition after loss of phase should be automatic. Return to on-line condition after loss of neutral may be either automatic, or manual. Verification:The design should be verified using FMEA to analyze effects.Full test of the design should include operation with loss of each phase and neutral under the following conditions:UPS offUPS on - No loadUPS on - Full loadIf the design is intended to stay on line during loss of phase or neutral, the tests should include high line and low line tests.High voltages which can result from loss of phase or neutral in 3 phase systems can easily exceed maximums for both UPS and load equipment resulting repair costs and down time for the customer.。
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版图验证
DRC:对 IC 版图做几何空间检查，以确保线路能够被
特定加工工艺实现。 ERC:检查电源、地的短路，悬空器件和节点等电气 特性。 LVS:将版图与电路原理图做对比，以检查电路的连 接，与MOS的长宽值是否匹配。 LPE:从版图数据库提取电气参数（如MOS的W、L值 BJT、二极管的面积，周长，结点寄生电容等） 并以Hspice 网表方式表示电路。
mason rule
Mason's ruleMason's gain formula is a method for finding the transfer function of a given control circuit/loop when you have the signal flow graph. It is used frequently in control theory, and was derived by Samuel Jefferson Mason.[1]It can be determined by looking at a signal-flow graph, or a block diagram. Mason's Gain Formula provides a step by step method to obtain the transfer function from a block diagram or signal flow graph. An alternate method would be to find the transfer function algebraically by labelling each signal, writing down the equation for how that signal depends on other signals, and then solving the multiple equations for the output signal in terms of the input signal. Some people prefer a more structured approach, and Mason's Formula may be easier or more difficult depending on the graph in question.Contents[hide]▪ 1 Formula▪ 2 Usage▪ 3 Equivalent matrix form▪ 4 Notes▪ 5 References[edit] FormulaThe gain formula is as follows:where:▪Δ = the determinant of the graph.▪y in= input-node variable▪y out= output-node variable▪G= complete gain between y in and y out▪N= total number of forward paths between y in and y out▪G k= gain of the k th forward path between y in and y out▪L i= loop gain of each closed loop in the system▪L i L j= product of the loop gains of any two non-touching loops (no common nodes)▪L i L j L k= product of the loop gains of any three pairwise nontouching loops▪Δk = the cofactor value of Δ for the k th forward path, with the loops touching the k th forward path removed. I.e. Remove those parts of the graph which form the loop, while retaining the parts needed for the forward path.[edit] UsageTo use this technique,1Make a list of all forward paths, and their gains, and label these G k.2Make a list of all the loops and their gains, and label these L i (for i loops). Make a list of all pairs of non-touching loops, and the products of their gains (L i L j). Make a list of all pairwise non-touchingloops taken three at a time (L i L j L k), then four at a time, and so forth, until there are no more.3Compute the determinant Δ and cofactors Δk.4Apply the formula.[edit] Equivalent matrix formMason's rule can be stated in a simple matrix form. Assume is the transient matrix of the graph where is the sum transmittance of branches from node m toward node n. Then, the gain from node m to node n of the graph is equal to , where,and is the identity matrix.There have been times when I wanted to determine the z-domain transfer function of some discrete network, but my algebra skills failed me. Some time ago I learned Mason's Rule, which helped me solve my problems. If you're willing to learn the steps in using Mason's Rule, it has the power of George Foreman's right hand in solving network analysis problems.This blog discusses a valuable analysis method (well known to our analog control system engineering brethren) to obtain the z-domain transfer function equations of digital signal processing (DSP) networks. That method, called "Mason's Rule" (sometimes called "Mason's Gain Formula"), was developed by Samuel Mason in the early 1950s to analyze interconnected analog systems[1-3]. Here we describe Mason's Rule and present several examples showing the utility of this network analysis technique. Mason's Rule enables us to determine the H(z) = Y(z)/X(z) transfer function of complicated networks, such as multi-feedback loop networks.Mason's Rule is also particularly useful for deriving the z-domain transfer function of, say, a discretenetwork that has inner feedback loops embedded within outer feedback loops (nested loops). Here's the good news: if we are able to draw the block diagram of some discrete network, then the application of Mason's Rule will give us that network's z-domain H(z) transfer function. Once we have H(z) we can then use all the algebraic and software tools at our command to determine the frequency-domain behavior, and stability, of the network. Here we describe Mason's Rule, accompanied by several examples, in the hope this robust analysis technique is of use to the reader in their future DSP network analysis efforts. For our purposes, Mason's Rule is a method to derive a discrete network's z-domain transfer function by identifying various forward paths from the input node to the output node of a discrete network, and the various feedback paths that may, or may not, share common signal nodes with those feedforward paths. This sounds mysterious, but it's not really too complicated. Let's define our Mason's Rule terminology and then demonstrate this analysis technique by way of examples.I. A Few DefinitionsMason's Rule is based on converting a network's block diagram to a signal flow diagram like that shown in Figure 2, and identifying crucial signal paths and loops.we establish the following definitions:A gain symbol is an arrowhead with its associated z-domain function (indicated by an uppercase letter), such as a sample delay (z-1) or a constant multiplier. The direction of the arrowhead shows the direction of signal flow. A signal node is a single point in the flow diagram. In Figure 2, signal nodes are indicated by an italicized lowercase letter. A path is a sequence of signal flow branches from one node to another node. A forward path is a path that travels from the x(n) input to the y(n) output, without going through the same node twice. In Figure 2, the path from node a to node g, [a,b,c,d,e,f,g], is a forward path. The gainof that forward path is the product ACDFGI. A loop is a path that starts and ends at the same node, with no node encountered more than once. That is, a loop is a feedback path. In Figure 2, the path from node b to node c and back to node b is a loop. A signal flow diagram, of course, can have multiple forward paths and multiple loops. Nontouching loops are two loops that do not share a common signal node. In Figure 2, the loops [b,c,b] and [d,e,d], for example, are nontouching loops. The loops [b,c,b] and [b,c,d,e,f,g,b] are touching loops because they share the signal nodes b and c. The loop gain of a loop is the product of all the branch gain symbols within a loop. In Figure 2, the loop gain of the [d,e,d] loop is the product FE. The loop gain of the [b,c,d,e,f,g,b] loop is the product CDFGIJ. With those simple definitions established (here comes the exciting part), we define the Δ(z) determinant of a signal flow diagram as: Δ(z) = 1 – the sum of all loop gains+ the sum of products of nontouching loop gains taken two at a time– the sum of products of nontouching loop gains taken three at a time+ ... etc. (1)The "nontouching loop gains taken two at a time" are the combinations of pairs of loop gains. The pairs of nontouching loop gains in Figure 2 are the loop gain combinations: CB,FE; CB,IH; and FE,IH. The "nontouching loop gains taken three at a time" are the combinations of triplets of loop gains. The only triplet of nontouching loop gains in Figure 2 is the loop gain combination: CB,FE,IH.The Δ(z) determinant for the diagram in Figure 2 isΔ(z) = 1 – (CB + FE + IH + CDFGIJ)+ (CBFE + CBIH + FEIH) – CBFEIH. (2)For each forward path in a signal flow diagram there is an associated determinant represented by Δi(z). If a diagram has P = 3 forward paths (designated as paths P1(z), P2(z), and P3(z)), then there will be a Δ1(z), a Δ2(z), and a Δ3(z) determinant. Subscript variable i is merely the index identifying the individual forward paths and their associated determinants. Determinant Δi(z) is the determinant of the signal flow diagram that does not touch the ith forward path. To ascertain Δ1(z), for example, we delete the P1(z) forward path in a signal flow diagram (and any branches that touch the P1(z) forward path) and use the above Eq. (1) for whatever signal flow paths that remain. If no loops remain after deleting the P1(z) forward path, then Δ1(z) = 1.To recap, a signal flow diagram has a Δ(z) determinant, and each Pi(z) forward path has a gain as well as its own Δi(z)(z) determinant. All determinants are defined by Eq. (1) once a diagram's loops have been determined. With all this said, we can now (finally) define Mason's Rule.[edit] Notes^Mason, Samuel J. (July 1956). "Feedback Theory - Further Properties of Signal Flow Graphs".Proceedings of the IRE: 920--926.[edit] References▪Bolton, W. Newnes (1998). Control。
Engineering Design Optimization
Engineering Design Optimization Engineering design optimization is a critical process in the field of engineering, as it involves finding the best possible solution to a given problem within the constraints of cost, time, and resources. This process requires a deep understanding of the problem at hand, as well as the ability to think creatively and analytically to come up with innovative and efficient solutions. However, it is not without its challenges, as engineers often face conflicting objectives and trade-offs that make the optimization process complex and difficult. One of the key challenges in engineering design optimization is the need to balance competing objectives. For example, when designing a new product, engineers may need to optimize for factors such as cost, performance, and reliability. However, these objectives are often in conflict with each other, making it difficult to find a solution that satisfies all of them simultaneously. This requires engineers to carefully consider the trade-offs involved and make difficult decisions about which objectives to prioritize. Another challenge in engineering design optimization is the need to account for uncertainty and variability. In many real-world engineering problems, the parameters and constraints are not known with certainty, and there may be variability in factors such as material properties, environmental conditions, and operating conditions. This uncertainty makes the optimization process more challenging, as engineers must account for the potential range of values for these parameters and ensure that the chosen solution is robust and reliable under a variety of conditions. Furthermore, the complexity of modern engineering systems presents a significant challenge in the optimization process. As systems become more interconnected and interdependent, the number of variables and constraints involved in the optimization process increases, making it more difficult to find an optimal solution. This complexity requires engineers to use advanced computational tools and techniques to effectively explore the design space and identify the best possible solutions. In addition to these technical challenges, there are also human and organizational factors that can impact the engineering design optimization process. For example, engineers may face pressure to meet tight deadlines or adhere to strict budget constraints, which can limit the time and resources available for optimization. Furthermore, organizationalstructures and cultures may impact the ability of engineers to collaborate effectively and make decisions that are in the best interest of the overall system. Despite these challenges, engineering design optimization offers significant opportunities for innovation and improvement in the field of engineering. Byfinding the best possible solutions to complex problems, engineers can improve the performance, efficiency, and reliability of systems and products, ultimately benefiting society as a whole. To overcome the challenges involved in engineering design optimization, engineers must leverage their technical expertise, creativity, and collaboration skills to develop robust and innovative solutions that meet the diverse and often conflicting objectives of modern engineering problems.。
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M. A. Matin, A. I. Sayeed
A Design Rule for Inset-fed Rectangular Microstrip Patch Antenna
M A MATIN, A. I. SAYEED Department of Electrical Engineering and Computer Science North South University Plot 15, Block B, Bashundhara, Dhaka 1229 BANGLADESH Email:matin@
Abstract: - In our paper, an inset-fed microstrip patch antenna has been designed and the dependency of resonant frequency on the notch gap and the feed line geometry has been studied. Our study suggests that a narrower notch resulted in better impedance matching. A design rule has also been formulated and presented the performance of the proposed design.
low cross-polarization radiation. There are many configurations that can be used to feed microstrip antennas. The four most popular feeding techniques are the microstrip line, coaxial probe, aperture coupling and proximity coupling [6] [7-13]. In our paper, we have chosen inset feed microstrip line with rectangular microstrip patch.
Key-Words: - Inset-fed, microstrip antenna
1 Introduction
Microstrip patch antennas have been widely used particularly since they are lightweight, compact and cost effective. The input impedance of these antennas depends on their geometrical shape, dimensions, the physical properties of the materials involved, the feed type and location. Therefore, a subset of antenna parameters can be adjusted to achieve the “best” geometry for matching of a particular resonance. The inset-fed microstrip antenna provides a method of impedance control with a planar feed configuration [1-2]. The experimental and numerical results showed that the input impedance of an inset-fed rectangular patch varied as a Cos 4 function of the normalized inset depth [1]. A more recent study proposed a modified shifted Sin 2 form that well characterizes probe-fed patches with a notch [3]. It is found that a shifted Cos 2 function works well for the inset-fed patch [4][5]. The parameters of the shifted cosine-squared function depend on the notch width for a given patch and substrate geometry. In our paper, we have analyzed the characterization of resonance frequencies as a function of notch width for an inset microstrip feed. An approximate formula is introduced to describe the resonance frequency that is then implemented in the design of notch width for inset-fed antennas to achieve better impedance matching.
10
2.2
9064 11895
3126 Width of the microstrip feed line, W in µm 2150
Often microstrip antennas are referred to as patch antennas. The radiating elements and the feed lines are habitually photo etched on the dielectric substrate. The radiating patch may be square, rectangular, thin strip, circular, elliptical, triangular or constituting any other configuration. Square, rectangular, thin strip and circular microstrip patch configurations are the most common because of their ease of analysis, fabrication, and their attractive radiation characteristics, especially the
Table 1: Physical dimensions of inset-fed microstrip patch antenna
Operating frequency, f in GHz Dielectric constant, ε reff Length of the patch, L p in µm Width of the patch, W p in µm Position of inset feed point, d in µm
[14] and the final values are determined through extensive numerical simulations which are shown in Table 1. The value of ‘g’ is changed with the ratio of ‘W/10’, ‘W/15’, ‘W/20’, W/25’, ‘W/30’ W/35’ and ‘W/40’ where W is the width of microstrip feed line.
2 Basic Characteristics of Microstrip Patch
The microstrip patch is designed such that its pattern maximum is normal to the patch (broadside radiator). This is accomplished through proper choice of the mode (field configuration) of excitation beneath the patch. End-fire radiation can also be accomplished by judicious mode selection. The ones that are most desirable for antenna performance are thick substrates whose dielectric constant is in the lower end of the range. This is because they provide better efficiency, larger bandwidth, loosely bound fields for radiation into space, but at the expense of larger element size [6]. Thin substrates with higher dielectric constants are attractive for microwave circuitry because they require tightly bound fields to minimize undesirable radiation and coupling, which lead to smaller element sizes; however, because of their greater losses, they are less efficient and have relatively smaller bandwidths [6]. Since microstrip antennas are often integrated with other microwave circuitry, a compromise has to be reached between good antenna performance and circuit design.