lesson 10
P1 P2
The mould designer is frequently confronted with a component design that incorporates a recess or projection which prevents the simple removal of the molding from the mould. The mould design for this type of component is inevitably more complex than for the in line of draw component, as it necessitates the removal of that part of the impression which forms the undercut prior to ejection
①.
The splits can be incorporated in the mould design in several ways. The designer considers more complex systems where the splits are retained on the mould plate and actuated automatically. There are two basic designs: sliding and angled-lift splits. In both designs there are moving parts and it is necessary to arrange for (i) guiding the splits in the desired direction, (ii) actuating the splits, and (iii) securely locking the splits in position prior to the material being injection into the moul d②.
模具设计师经常面临的一个组成部分的设计，包括凹槽或投影，防止简单去除成型模具。因为脱模前要先抽出形成侧型芯的那部分型腔，这类零件的模具设计比直接脱模的零件复杂的多。
滑块可纳入模具设计的几种方法。设计师认为，更复杂的系统，滑块将自动保留并驱动在模板中。有两个个基本的设计思路：滑动和斜滑块。
在两者的设计中都有活动零件，而且有必要安排：沿着正确方向导向滑块，驱动滑块，在材料注射进模具之前安全地锁紧滑块。
Lesson 1
The injection molding and machine
1.1The injection molding
2Injection molding is principally used for the production of the thermoplastic parts, although some progress has been made in developing a method for injection molding some thermosetting materials. The problem of injecting a melted plastic into a mold cavity from a reservoir of melted material has been extremely difficult to solve for thermosetting plastics which cure and harden under such conditions within a few minute s①. The principle of injection molding is quite similar to that of die-casting. The process consists of feeding a plastic compound in powdered or granular from a hopper through metering and melting stages and then injecting it into a mol d②. After a brief cooling period, the mold is opened and the solidified part ejected. Injection-molding machines can be arranged for manual operation, automatic single-cycle operation, and full automatic operation. The advantage of injection molding are: (i) a high molding speed adapted for mass production is possible; (ii) there is a wide choice of thermoplastic materials providing a variety of useful properties; (iii) it is
possible to mold threads, undercuts, side holes, and large thin sections.
2.1
注塑成型主要用于生产热塑性塑料配件，虽然已经取得了一些进展，在发展中国家的一些热固性材料注塑成型的方法。问题的注射熔融塑料在模腔的熔融材料的容器已极难处理热固性塑料固
化和硬化，在这种情况下，几分钟内①。注塑成型原理很相似，压铸。这个过程包括喂养塑料复合粉末或颗粒从料斗通过计量和融化阶段，然后注射到模具②。经过短暂的冷却时间，打开模
具和固化部分弹出。注塑机可设置为手工操作，自动循环操作，全自动操作。利用注射成型是：（一）高成形速度为适应大规模生产是可能的；（二）有多种可供选择的热塑性材料提供各种
有用的性质；（三）是有可能的模具，削弱，侧孔，和大的薄片。
Lesson2 Mould for threaded components
2.2 Stripping internal threads
The internally thread component may be stripped from the core using the basic stripper plate design providing the plastic material has sufficient elasticity during the ejection phase②. The same principle applies here as to stripping any internal undercut, i.e. the molding must be free to expand during ejection to permit the molded undercut to ride over the restriction on the core③. This means that the outside form of the component must be such that it can be formed in a cavity which is fully contained in one half of the mould.
Amould of this type is illustrated in Figure 2-1. This diagram shows a single impression mould for an internally threaded cap. The mould opens initially and, because of molding shrinkage and the undercut form, the molding is withdrawn from the cavity. During the latter stages of opening the stripper plate’s movement is checked, thereby causing the second opening to occur at B. The molding is, therefore, progressively stripped as the core is withdrawn through the stripper plate. The aperture in the stripper plate must be slightly larger in diameter than the major diameter of the thread in order to prevent scoring of the thread.
内螺纹组件可能被剥夺的核心采用推板设计提供塑料材料有足够的弹性在弹射阶段②。同样的原则适用于这里作为剥离的任何内部削弱，即成型必须自由扩大在弹射允许成型凹穴通过限制的
核心③。这意味着，外部组件形式必须是这样的：它可以形成一个腔是完全包含在一个半的模具。模具这种类型是说明了在图2 - 1。这个图显示了一个单一的印象模具内螺纹帽。模具打开了
最初，因为成型收缩和削弱形式，成型退出腔。在后期的开放料板检查，从而造成二开口发生在B成型，因此，逐步剥离为核心撤回通过卸料板。光圈在料板必须稍微比直径大的大直
为防止得分线。
Lesson 3 Basic underfeed mould
P1 P2 P3
The moving half consists of the moving mould plate assembly, support blocks, backing plate, ejector assembly and the pin ejection system. Thus the moving half in this design is identical with the moving half of basic moulds.
The floating cavity plate, which may be of the integer or insert-bolster design, is located on substantial guide pillars (not shown) fitted in the feed plate. These guide pillars must be of sufficient length to support the floating cavity plate over its full movement and still project to perform the function of alignment between the cavity and core when the mould is being close d. Guide bushes are fitted into the moving mould plate and the floating cavity plate respectively.
The maximum movement of the floating cavity plate is controlled by stop bolts or similar devices. The moving mould plate is suitably bored to provide a clearance for the stop bolt assembly. The stop bolts must be long enough to provide sufficient space between the feed plate and the floating cavity plate for easy removal of the feed system. The minimum space provided for should be 65mm just sufficient for an operator to remove the feed system by hand if necessary.
一个简单的模具，这种类型是显示在图3 - 1，并说明设计和开放序列如下。模具由三个基本部分组成，即：移动一半，浮动型腔板和板的饲料，分别。移动一半由动模板组件，支持块，底板
，喷射器装配和针弹射系统。因此，移动一半在这设计相同的移动半年基本模。浮动型腔板，这可能是整数或insert-bolster设计，位于大幅度的导柱（未显示）安装在饲料盘。这些导柱必
须有足够的长度支持浮动型腔板在其充分的运动和仍然项目履行的职能，调整之间的型腔和型芯的模具时关闭。导衬套安装到移动模具板和浮动型腔板分别。
Lesson 4 Feed system
Gate
A gate is an entrance through which molten plastic enters the cavity.The gate has the following functions: restricts the flow and the direction of molten plastic; simplifies cutting of a runner and moldings to simplify finishing of parts; quickly cools and solidifies to avoid backflow after molten plastic has filled up in the cavity.
浇口是一个入口通过它熔融塑料进入型腔。浇口有以下功能：限制流量和方向的熔融塑料；简化了切割的亚军和造型简化零件精加工；快速冷却并固化，避免回流后，熔融塑料填补了
Cold slug well
The purpose of the cold slug well, shown opposite the sprue, is theoretically to receive the material that has chilled at the front of the nozzle during the cooling and ejection phase ②. Perhaps of greater importance is the fact that it provides positive means whereby the sprue can be pulled from the sprue bush for ejection purposes.
冷料口的作用，正对浇口，理论上得到冷料喷嘴前端在冷却和射血期②。也许更重要的事实是，它提供了积极的手段，使浇口可以被从浇口套弹射的目的。
Lesson5 Sprue bush and Register ring
P1 P2 P3
The sprue bush is defined as that part if the mould in which the sprue is formed. In practice the sprue bush is the connecting member between the machine nozzle and the mould face, and provides suitable aperture through which the material can travel on its way to the impressions or to the start of the runner system in multi-impression moulds.
The sprue bush is fairly highly stressed in some applications and should therefore be made from a %2
11 nickel chrome steel and should always be hardened. Note that while initially the nozzle may have been set up correctly, an increase in the injection cylinder temperature will cause a fairly high force to be applied to the sprue bush because of the expansion of the injection cylinde r ①.
The internal aperture of the sprue bush has between 2°and 4°included taper, which facilitates removal of the sprue from the mould at the end of molding cycle. For reference, 2; 2.6; 3 and 4 are the included tapers adopted by various standard parts suppliers.
浇口套的定义是部分的模具中，流道形成。在实践中，浇道衬套连接成员之间的喷嘴和模具，并提供合适的光圈通过它可以旅行的道路上的印象或开始的多型腔模具浇注系统。
浇口套相当高度强调在一些应用程序，因此应该从镍铬钢和应始终硬化。注意，虽然最初的喷嘴可能被正确设置，增加了注射温度会产生相当高的力量适用于主流道衬套因为膨胀的注射
筒①。
Lesson6 RUNNER
Runner cross-section shape
The cross-sectional shape of the runner used in a mould is usually one of four forms (Figure 6-1): fully round (a), trapezoidal (b), modified trapezoidal(c) and hexagonal (d).
The criterion of efficient runner design is that the runner should provide a maximum cross-section area from the standpoint of pressure transfer and a minimum contact on the
periphery from the standpoint of heat transfe r①. The ratio of cross-sectional area to periphery will, therefore, give a direct indication of the efficiency of the runner design; the higher the value the greater the efficiency. Ratios for various types of runner section are given in Figure 6-2 . As can be seen, the round and square types of runner are the two most satisfactory designs from this standpoint; whereas the ratios exhibited by the semicircular and rectangular types make their use generally undesirable.
流道横截面形状用于模具通常是四种形式之一（图1）：全圆（一），（二）修正梯形梯形，（三）和（四）。有效率的流道设计标准是运动员应该提供最大横截面积从压力传递和最低的接触
从热传递①。比例横断面地区周边将，因此，给予直接说明效率的流道设计；较高的价值更大的效率。比率为各类亚军部分是由于在图6 - 2。可以看出，该圆形和方形类型的运动员是最满意
的设计，从这个角度；而比展出的半圆形和矩形类型，使它们的使用一般不良。
Lesson7 GATES
Type of gate前两段
The size of the gate can be consideredin terms of the gate cross-sectional area and the gate length, the latter being known as gate land. The optimum size for a gate will depend on a number of factors including (i) the flow characteristics of the material to be molded (ii) the wall section of the molding,(iii)the volume of material to be injected into the impression, (iv)the temperature of the melt, and(v) the temperature of the mould.
No theoretical size exists for the ideal gate. The gate size chosen in practice for a particular component is normally based on past experience. However, the reader may not have this experience upon which to base a decision and, therefore, a guide to the dimensions for each gate type is given. The guide applies, except where otherwise stared, to the general case of a molding with a wall section between 0.75mmand 4 mm.
浇口可被视为在该门横截面积和栅极长度，后者被称为门的土地。最佳尺寸为栅将取决于若干因素，包括（一）流动特性的模制材料（二）的壁部分成型，（三）材料的数量被注入的印象，
（四）熔体的温度，和（五）的模温。
没有理论大小存在的理想大门。门的大小选择在实践中的特定组件通常是根据过去的经验。然而，读者可能没有这方面的经验为基础的决策，因此，指导的规模每个门式是。本指南适用，除
非另有凝视，在一般情况下一个成型的一段围墙0.75毫米和4毫米之间。
Lesson8 Parting surface
FLAT PARTING SURFACE
The mature of the parting surface depends entirely on the shape of the component. For
instance, the parting surface of the rectangular molding is shown in Figure 8-1(a). The cavity for this article can be die-sunk into one mould plate. The position of the parting surface will therefore be at the top of the molding, the parting surface itself being perfectly flat. For appearance this is the ideal arrangement as the parting line is not noticeable unless flash develops.
A further consideration is that the parting surface must be chosen so that the molding can be removed from the mould. Figure 8-1(b) shows the parting surface of a flat rectangular molding which incorporates a double-bevel edge. The suitable choice for the parting line is on the centre of the double-bevel which allows for half of the required form to be die-sunk into each of the two mould halves.
The parting line must occur along the line round the position of maximum dimension when viewed in the draw direction. Then is this line lies on a plane the parting surface will be flat.
完整的分型面完全取决于形状的部件。例如，分型面成型的矩形显示在图8 - 1（一）。腔为这篇文章可以die-sunk到一个模具板。位置的分型面，因此将在顶部的模，分型面本身是完全持平
。外观这是理想的安排分模线并不明显，除非快速发展。另一个考虑是，分型面必须选择，使成型可以从模具中删除。图8 - 1（乙）显示，分别表面的平面矩形，采用了双边缘。选择适合的
分模线的中心的双允许一半所需的形式是die-sunk成一个半模。分模线必须发生沿线的位置附近的最大尺寸时，在拉伸方向。然后这是位于一个平面分型面是平。
Lesson9 MOULD CAVITIES AND CORES
8.1 Integer cavity and core plates
When the cavity or core is machined from a large plate or block of steel, or is cast in one piece, and used without bolstering as one of the mould plates, it is termed an integer cavity plate or integer core plate. This design is preferred for single-impression moulds because of the strength, smaller size and lower cost characteristics. It is not used as much for multi-impression moulds as there are other factors such as alignment which must be taken into consideration.
Of the many manufacturing processes available for preparing moulds only two are normally used in this case. These are (a) a direct machining operation on a rough steel forging or blank using the conventional machine tools, or (b) the ‘precision’ investment casting technique in which a master pattern is made of the cavity and core①. The pattern is then used to prepare a casting of the cavity or core by a special process. A 4.25% nickel-chrome-molybdenum steel (BS 970-835 M30) is normally specified for integer mould plates which are to be made by the direct machining method. The precision investment casting method usually utilizes a high-chrome steel.
当腔或核心是从加工大型板或钢块，或是投在一片，使用不支持为一体的模具板，它被称为整数或整数的腔板芯板。这种设计是首选的single-impression模具因为实力，更小的尺寸和更低成
本的特点。它不使用过多型腔的模具有等其他因素，必须考虑到。在众多的制造工艺可用于
制备模2通常在这种情况下使用。这是（一）直接加工操作粗钢锻或空白使用传统工具机，或（乙）
’精密熔模铸造技术，主图案是由腔和核心①。该模式然后用于编写铸造腔或核心的一个特殊过程。4.25%钼钢铁（学士970-835木工）是通常指定为整数的模具板是由直接加工方法。精密熔
模铸造方法通常采用高铬铸钢。
LESSON 16 MACHINE TOOLS
P4 P5 P6
ii.Cylindrical grinding machines for the production of precision cylindrical surfaces. The cylindrical grinding machine is used for precision grinding cylindrical mould parts. Metal is removed by the action of abrasive grinding wheel which is brought into contact with a contra-rotating workpiece. iii.Shaping and planning machines for the reduction of steel blocks and plates to the required thickness and for ‘squaring up’ these plates②.As the primary purpose of a shaping machine is to produce flat surfaces, this machine tool is used in the initial preparation of mould blocks. The workpiece is mounted on a table and a reciprocating single-point tool removes metal in a series of straight cuts.
iv.Surface grinding machines for the production of precision flat surfaces. An excellent surface finish combined with accuracy can be achieved on hard or soft steel with the surface grinding machine. The workpiece is mounted on a table which is reciprocated beneath a rotating abrasive grinding wheel and metal is removed in a series of straight cuts.
二。外圆磨床为生产精密圆柱面。圆筒磨床用于磨削圆柱形零件精密模具。金属被删除的行动磨料砂轮是接触带来了一个旋转工件。
三、塑造和策划机的钢坯和钢板的厚度和'与'这些板块②。作为主要目的的一种成型机是生产平面，本机是用于初步制备块模具。工件安装在一个表和一个往复式单点工具去除金属的一系列
直线切割。
四、表面研磨机用于生产精密平面。一个优秀的表面结合的精度可以达到硬或软带表面研磨机。工件安装在一个表的回报是下一个旋转磨料砂轮和金属被删除的一系列直线切割。
下面的范文中有很多错误，请找出形容词与副词的混淆、冠词的遗漏和误用、介词和代词的误用等错误，并检查句子的完整性、单词拼写、主谓的一致性、动词和现在分词是否混淆、复数形式、动词的时态、词汇选择、词性、单词的顺序等问题。 (几乎每个句子都有错误) An university education is a goal of many high school students. Some students want to go into a profession that requires an university degree. But there are other professions that do not require a degree, but require certification from a technological college. The reasons why students make decisions to go to technical college instead of university probably have a lot to do with their choice of career, their own academic abilities and their financial situation. First of all, students make their choices for post-secondary education based on the fields that interest them. A student who is interested in medicine might decide to university, into a pre-med program to prepare to become a doctor, or they might go to nursing school or a nursing program in a technical college. Some career choices offer a choice of educational route. The university route is usually more intense and takes longer. For example, an interior designer might take a one or two year program at a college, or choose to do the degree program as a part of the architectural department at a university. Other career choices involve certification that is available at a college, like broadcast journal or
专业英语大作业 一：英译汉 翻译范围TCP/IP Illustrated, V olume 1: The Protocols 5.1~5.5 15.1~15.2 第5章RARP：逆地址解析协议 5.1简介 5.2 RARP报文格式 5.3 RARP示例 5.4 RARP服务的设计 5.5小结 练习 5.1简介 一个拥有本地磁盘的系统通常是从磁盘文件读取配置文件中获取其IP地址。但一个没有磁盘的系统，如X终端或无盘工作站，需要一些其它方式去获得其IP地址。 每个系统在网络上都有一个唯一的硬件地址，由网络接口的制造商分配。 RARP的原则是无盘系统从接口卡上读取其独特的硬件地址，并发送RARP请求（网络上的广播帧）要求别人对无盘系统的IP地址（使用RARP回应）进行应答。 虽然这个概念很简单，执行往往比ARP更难，在本章后面会描述其原因。 RARP的正式规范是RFC 903。 5.2 RARP报文格式 RARP报文的格式几乎与ARP报文是相同的（图4.3）。唯一的区别是，RARP 的请求或应答帧类型为0×8035，并且在操作层RARP请求值为3、RARP应答值为4。 图4-3 ARP在网络上请求与应答报文的格式 与ARP一样，RARP服务器请求是广播和RARP应答通常是单播。 5.3 RARP示例 在我们的网络，我们可以强制sun主机从网络引导，而不是它的本地磁盘。 如果我们在主机bsdi上运行RARP服务器和tcpdump，我们得到如图5.1所示的输出。我们使用-e参数去标记tcpdump的打印硬件地址：
图5.1 RARP请求和应答。 该RARP请求是广播（1号线）的，第2行的RARP应答是单播的。第2行的输出，“at sun”,意味着RARP应答包含了主机sun（140.252.13.33）的IP地址。 在第3行，我们看到，一旦sun接收其IP地址，它会发出一个TFTP读请求（RRQ）的文件8CFCOD21.SUN4C。（TFTP是简单文件传输协议，我们在第15章进行详细描述）。在文件名中的8个十六进制数字是sun主机的IP地址140.252.13.33的十六进制表示形式。这是在RARP应答中返回的IP地址。该文件名的其余部分，后缀SUN4C表示系统正在引导的类型。 Tcpdump表示第3行是一个长度为65的IP数据报，而不是一个UDP数据报（实际上它确实是），因为我们运行tcpdump命令使用-e参数，看硬件级别的地址。另一点，在图5.1要注意的是在第2行的以太网帧的长度似乎比最小较短（我们所说的是在4.5节60字节）。原因是我们的系统，该系统上运行的tcpdump 发送该以太网帧（BSDI）。该应用程序rarpd，写42字节到BSD分组过滤器装置（14字节的以太网报头和28字节的RARP应答），这是什么的tcpdump收到的副本。但以太网设备驱动程序垫这个短帧的最小尺寸为传输（60 ）。如果我们在另一个系统上已经运行的tcpdump ，长度会是60。 我们可以看到在这个例子，当这种无盘系统接收在RARP应答它的IP地址，它会发出一个TFTP请求来读取一个引导映像。在这一点上，我们不会进入其他详细介绍无盘系统是如何引导自己。（第16章介绍了使用RARP ，BOOTP和TFTP无盘X终端的引导顺序。） 图5.2表示出了如果有在网络上没有RARP服务器所得到的数据包。每个数据包的目的地址为以太网的广播地址。以太网地址跟随的是目标硬件地址，并按照发送端的硬件地址发送。
全国农业推广硕士专业英语作业题 Part One Vocabulary and Structure Fill in the balnks with words or expressions chosen from the following list. Change the form where necessary. speculate specify commitment despite desirable access contribution adolescent banish inhabitant identify frustration impact sanction impressive hit upon switch correspond to obligation various 1、The U.N would impose economic against the offending nations or government. 2、The boys and girls are fond of behaving differently from seniors. 3、I a satisfactory explanation. 4、Man on the origin of the universe since the beginning og the human history. 5、You can from your mind the idea of holding a party during
the examination week. 6、The company that we would have one subject to another. 7、The American Congree the British Parliament. 8、We are trying to find some people who have a real sense of to the job. 9、the sandstorm, the Johnsons drove to the xilla to celebrate their 25th anniversary of marriage. 10、You are under no to pay for goods which you did not order. 11、Men still hold the vast majority of the least- or modt-dangerous jobs, such as loggers and miners. 12、He doesn’t expect to see changes overnight. 13、Students must have to good books.
电力系统power system 发电机generator 励磁excitation 励磁器excitor 电压voltage 电流current 升压变压器step-up transformer 母线bus 变压器transformer 空载损耗no-load loss 铁损iron loss 铜损copper loss 空载电流no-load current 有功损耗active loss 无功损耗reactive loss 输电系统power transmission system 高压侧high side 输电线transmission line 高压high voltage 低压low voltage 中压middle voltage 功角稳定angle stability 稳定stability 电压稳定voltage stability 暂态稳定transient stability 电厂power plant 能量输送power transfer 交流AC 直流DC 电网power system 落点drop point 开关站switch station 调节regulation 高抗high voltage shunt reactor 并列的apposable 裕度margin 故障fault 三相故障three phase fault 分接头tap 切机generator triping 高顶值high limited value 静态static (state) 动态dynamic (state) 机端电压控制AVR 电抗reactance 电阻resistance 功角power angle 有功（功率）active power 电容器Capacitor 电抗器Reactor 断路器Breaker 电动机motor 功率因数power-factor 定子stator 阻抗impedance 功角power-angle 电压等级voltage grade 有功负载: active load PLoad 无功负载reactive load 档位tap position 电阻resistor 电抗reactance 电导conductance 电纳susceptance 上限upper limit 下限lower limit 正序阻抗positive sequence impedance 负序阻抗negative sequence impedance 零序阻抗zero sequence impedance 无功（功率）reactive power 功率因数power factor 无功电流reactive current 斜率slope 额定rating 变比ratio 参考值reference value 电压互感器PT 分接头tap 仿真分析simulation analysis 下降率droop rate 传递函数transfer function 框图block diagram 受端receive-side
电大资源网《人文英语（2）》形成性考核册参考资料 《人文英语（2）》是国家开放大学 2017 年春季新开的课程之一，对国家开放大学的文科专业学生进行统一考试。该资料对学生完成学习任务起着一定的辅助作用。电大资源网还有国家开放大学其他课程的参考资料，可以参考。 注：本科目已按字母排版整理成期末考试小抄 作业 1 一、交际用语（每小题 2 分，共 10 分） 1-5 题：选择正确的语句完成下列对话，并将答案序号写在题前括号内。 1.-Would you like me to help you make a plan for the summer vacation? B - . A.No, I already have my plans. B.I’d love to, but I’m busy today. C.I’m ill, so I shouldn’t go out. 2.-Can I take your order, madam? A - . A.Yes. I’d like an Italian soup to start with. B.Yes, it’s as quiet as we expected. C.No, the price’s reasonable. 3.-What are you going to do in the 2022 Winter Olympics? B - . A.Yes, I have been there. B.I’m going to be a volunteer. C.I am traveling abroad. 4.-I’d like to invite you to my birthday party on Saturday evening. A - . A.Thank you for your invitation. B.I don’t want to join your party. C.I did not go to the party that night. 5.-Do you think you are the suitable person for this position? C - . A.I’m not sure if I will be here for the task. B.I don’t think Xiao Ming is the right person to count on. C.Yes. I’m hard working and I think I am suitable for this position. 二、选择填空（每小题 2 分，共 30 分） 6-20 题：阅读下面的句子，从 A、B、C 三个选项中选出一个能填入空白处的最佳选项，并将答案序号写在题前括号内。 6.I think I am C for this position. https://www.doczj.com/doc/355961313.html,plete B. confident C. competent 7. A successful cover letter will make a great B. A.progress B. impression C. contribution 8.Will the AIDS patients benefit A the new drug? A.from B. by C. of 9.You can B some bottles of wine, or some chocolates, or a bunch of flowers. A. bring up B. bring along C. bring down 10.I’m A because there are so many options. I can’t make a decision. A.puzzled B. excited C. depressed 11.If there is any change about the time of the meeting, please notify us C. A.in time B. on time C. in advance 12.There must be something wrong with my computer，C there? A.mustn’t B. needn’t C. isn’t
《自动化专业英语》翻译大作业 所选文字出处：选自论文《PLC的发展和应用》 班级：学号：姓名：成绩： PLC全名为可编程控制器，定义是种数字运算操作的电子系统，专为在工业环境应用而设计的，主要结构由电源，中央处理单元，存储器，输入输出接口电路，功能模块，通信模块组成。PLC具有通用性强、使用方便、适应面广、抗干扰性强、编程简单等特点，在军事、国防、航空航天、交通、工业生产中的地位，在可预见的将来中是无法取代的。PLC有很多流派，我国的PLC研发、生产和应用发展很快，尤其在应用方面更为突出。 PLC的发展历程和主要流派 在工业生产过程中，大量的开关量顺序控制，它按照逻辑条件进行顺序动作，并按照逻辑关系进行连锁保护动作的控制，及大量离散量的数据采集。传统上，这些功能是通过气动或电气控制系统来实现的。1968年美国GM（通用汽车）公司提出取代继电气控制装置的要求，第二年，美国数字公司研制出了基于集成电路和电子技术的控制装置，首次采用程序化的手段应用于电气控制，这就是第一代可编程序控制器，称Programmable Controller（PC）。个人计算机（简称PC）发展起来后，为了方便，也为了反映可编程控制器的功能特点，可编程序控制器定名为Programmable Logic Controller（PLC），现在，仍常常将PLC简称PC。PLC的定义有许多种。国际电工委员会（IEC）对PLC的定义是：可编程控制器是一种数字运算操作的电子系统，专为在工业环境下应用而设计。它采用可编程序的存贮器，用来在其内部存贮执行逻辑运算、顺序控制、定时、计数和算术运算等操作的指令，并通过数字的、模拟的输入和输出，控制各种类型的机械或生产过程。可编程序控制器及其有关设备，都应按易于与工业控制系统形成一个整体，易于扩充其功能的原则设计。上世纪80年代至90年代中期，是PLC发展最快的时期，年增长率一直保持为30~40%。在这时期，PLC在处理模拟量能力、数字运算能力、人机接口能力和网络能力得到大幅度提高，PLC逐渐进入过程控制领域，在某些应用上取代了在过程控制领域处于统治地位的DCS系统。在世界上200多家PLC厂商，400多品种的PLC产品大体可以按地域分成三个流派：一个流派是美国产品，一个流派是欧洲产品，还有一个流派是日本产品。同一地区的产品相互借鉴的比较多，相互影响比较大，技术参透比较深，面临的主要市场相同，拥护要求接近，这一切就使得同一地域的PLC产品表现出比较多的相似性。美国PLC技术的形成与欧洲PLC技术的形成是在相互隔离的情况下，独自研究开发获得的，因此美国的PLC产品与欧洲的PLC产品常表现出来明显的差异性。日本的PLC技术是由美国引进的，因此日本的产品对美国的产品有一定的继承性。世界上比较先进的PLC生产厂家有德国的的西门子、日本的三菱、美国的A-B公司等等。
1、A VPN is physically public but virtually private 2、Set is a secure protocol jointly designed by Mastercard and Visa with the backing of Microsoft, Netscape, IBM, GTE, SAIC, and other companies. 3、 The physical components of a computer are collectively called hardware 4、The term payment card refers to Credit card 、Charge card 5、The fifth generation computers, with artificial intelligence,are being developed and perfected now. 6、In the future, we may eliminate the needs for physical money.Indeed ,we would exchange digital cash For goods and services. 7、The basic input device on a small computer is a keyboard 8、You must have seen her in her office last Friday; she's been out of town for two weeks. 9、The ability to store knowledge makes computers different from every other machine ever invented. 10、The fifth generation computers, with artificial intelligence,are being developed and perfected now. 11、DigiCash or E-cash is an electronic payment system developed by Dr.David Chaum, who is widely regarded as an inventor of digital cash. 12、Transaction changed to your telephone bill are called E-charge payments 13、Smart cards are cards that look like credit cards, but store information on a microprocessor chip instead of magnetic strips. 14、https://www.doczj.com/doc/355961313.html, is a free service that earns a profit on the transaction cost, which is money that is deposited in PayPal accounts 15、This ticket entitles you to a free meal in our new restaurant 16、Program that can destroy another computer’s programs are called viruses 17、Data and program instructions are stored in storage 18、Electronic wallets that store digital certificates are particularyly handy when you shop at a site that requests user authentication information. 19、The percentage of times an ad is clicked on based on the number of times it’s viewed is called CTR 20、The purpose of input device is to enter commands .、to input data
计算机专业英语作业答案（供参考） 计算机专业英语作业1 第1－3章作业一．( 词汇) (一)．(写出下列词组的汉语。) 1．（）中央处理器 2 标题栏 3．操作系统4．个人计算机 5．菜单栏6．桌面排版 7．电子表格8．硬盘 9．数据库10．光标 (二)．.(根据汉语写出相应的英语缩写。) 1．随机存储器2．只读存储器 3．传输控制协议P 4．数字视频光盘5．通用串行总线6．计算机辅助设计7．计算机辅助制造8．中央处理器 (三)．.(根据汉语写出相应的英语。) 1．键盘2．鼠标3．扫描仪 4．打印机5．输入6．输出 7．显示器8．存储器9．数据库 10．操作系统11．应用软件 12．字处理器13．网络浏览器 二．(T) (F).(判断正误。) 1．, . (√)
2．'s . (√) 3．: . (√) 4． a 2000 . (×) 5．( ) a . (√) 6. , a . (√) 7. , ’s . (×) 8. ’t . (×) 9. . (×) 10. . (×). 三．.(将左列的词汇与右列相应的汉语匹配。) （一）． 1. （） a. 操作系统 2. b. 输入. 3. ( ) c. 只读存储器 4. ( ) d. 应用软件 5. e. 中央处理器 6. f. 系统软件 7. g. 硬件 8. h. 随机存储器 9. i. 内存 10. j. 输出 1．e 6. j 2．g 7．a 3．h 8. d 4．c 9. f 5．b 10. i (二) ． 1. a
2. b a 3. c 4 d a 0 1 5. e a 6. f 7. g 8. h a 9. i a 1．d 6. a 2．g 7．f 3．h 8. c 4．b 9. e 5．i 四．, . （从下面方框中选择合适的词或表达，以其适当的形式填空。） 1． () . , a . , . , , . , . 2. , , . , a a a , a , a , a . , , . a , , a . , 1-2-3 . a , a ( ) . 3.
1、(5) Which of the following is not true? ADick stayed at a nice hotel in the center of the city. BDick didn't work on the first night of his arrival. CDick forgot to send his wife a telegram. DDick wanted to go back to his hotel in a taxi. 正确答案C 2、题目Reading comprehension 1(4) Who would send him the name and address of his hotel? AThe manager of his hotel. BThe police office. CThe taxi driver. DHis wife.
正确答案D 3、题目Reading comprehension 1(3)Where did Dick stay in New York? A In the center of the city. BIn a hotel. CIn a restaurant. DAt his friend's house. 正确答案B 4、题目Reading comprehension 1(2) Why did his wife want a telegram from him? ABecause she didn’t know his address yet
BBecause she wanted to go to New York, too CBecause she might send him another telegram DBecause she couldn't leave her husband by himself in New York. 正确答案A 5、1) Dick flew to New York because _________. Ahe went there for a holiday Bhe had work there Che went there for sightseeing D his home was there 正确答案B
1. 获取更多信息如摘要的格式和类别,请参考附上的“提交摘要说明”。 For more information such as the format and the categories of the abstract, please refer to the attached “Instructions for Submission of Abstracts”. 2. 随信寄上两份论文摘要和一份个人简历，请查收。请便中告知我是否有资格申请大会的资助。 We are enclosing two copies of paper and a resume, please check. Please inform me if there are eligible to apply for funding of the conference. 3.非常感谢你的信息和对GEC2004感兴趣。不幸的是我们对参与者不提供任何财务援助。对组织会议有很大帮助的人将会提供一些金融帮助,例如给主题演讲或教程,组织一个邀请会话等。 Thank you very much for your message and for your interest in GEC2004. Unfortunately we can’t offer any financial assistance for regular participants. There will be some financial help available only for people who give considerable help in organizing the conference, e.g. giving a keynote lecture or a tutorial, organizing an invited session, etc. 4. 感谢你的8月15日来信，邀请我去参加2003年1月25日至28日在密歇根州的Bellaire即将举行的“2003国际会议比较文学”。
电气自动化专业英语 abbreviate 缩写，缩写为 abscissa axis 横坐标 absolute encoder 绝对编码器 ac squirrel cage induction motor 交流笼型感应电动机ac motor 交流环电动机 academic 纯理论的 accelerometer 加速度测量仪 accommodate 适应 accutrol 控制器 acoustic wave 声波 active 有源的 active region 动态区域 active filter 有源滤波器 active component 有功分量 active in respect to 相对….呈阻性 active(passive) circuit elements 有(无)源电路元件actuate 激励，驱动 actuator 执行机构 actuator 执行器 adjacent 临近的,接近的 adjacent 相邻的，邻近的 Adjustable-voltage inverter 电压型逆变器admittance 导纳 advent 出现 air gap 气隙 aircraft 飞机 air-gap flux 气隙磁通 air-gap line 气隙磁化线 air-gap flux distribution 气隙磁通分布 algebraic 代数的 algebraic 代数的 algebraical 代数的 algorithm 算法 algorithmic 算法的 align 调整，校准 allowable temperature rise 允许温升 alloy 合金 allude 暗指，直接提到 alnico 铝镍钴合金 alphabet 字母表 alternating current, AC 交流
PART1: Reading How to quickly read an English paper? Metalworking Glossary Cutting Tool Engineering, November, 2000, 209-238 The metalworking glossary defines terms common to those who cut and grind metals and other materials. The terms are divided into 11 categories: 1.Manufacturing Definitions; 2.Machining Operations; 3.Machine Tools and Ancillary Equipment; 4.Cutting Tools and Related Terminology 5.Coolants, Lubricants, and Related Terminology 6.Accessories and Attachments; 7.Alloys, Coatings, Material Compositions, and Related Terminology; 8.Heat-treating and Special Processes; 9.Inspection, Measurement, and Quality Control; 10.Robotics and Automated Assembly; 11.Nontraditional Machining How to Make Use of the Linguistic Features of Scientific Papers (科技论文的语言特点) 1.Linguistic Style(语体) 科学技术领域，科技工作者的任务： 描述自然现象 分析自然现象产生的规律 研究自然现象应用于人类生产实践 的方法 表达所取得的成果及其应用 思维形式：概念、公式或公式化的概念 思维活动的语言表达：按照严格的逻辑程序导 出的判断和推理，科技文体具有抽象性、概念 性和高度的逻辑性 内容：写实 语言风格：准确严谨、合乎逻辑，非形象性(理 性)、客观性、无明显感情色彩、简洁明快。Literature 1.Conference paper 2.Journal paper 3.Lecture 4.Book (Dissertation or Thesis) 5.Report (News) 6.Manual and Specification Paper and Experimental Report: Title, Abstract, Introduction, Results and Analysis, Conclusion and Discussion Book & Lecture: Title, Author(s), Name of the process or publisher, Name of the printing House, Name of the distributor, Date of publication, Date of printing, Synopsis, Note by the publisher, International Standard Book Number, Preface or Foreword, Acknowledgements, Contents, Text of the book, Appendix or Supplement, Index, Epilogue Manual and Instructions, Directions: Principle, Operation, Maintenance 2.Vocabulary Typically Professionalized Terms Whenever a force acts on a body so as to make the body move through some distance, it is said to have done work. Body n. 身体, 肉体, 人, 尸体, 主要部分, 团体, 大量vt. 赋以形体 机械专业n. 车身,机身
第五章的参考译文：仅供参考，不恰当的地方，请自行修改补充，欢迎通过Email（qiulk@https://www.doczj.com/doc/355961313.html,）进行讨论和交流。 5.1 电动机发展简史 电动机已经存在很多年了。自从多年前的第一次应用以来，电动机的应用领域快速地扩大了。目前，其应用范围继续以快速增长。 托马斯.爱迪生因提出了大规模发电和传输电力而得名。他完成了由蒸汽机驱动的直流发电机的研发工作。爱迪生在电灯和发电方面的贡献引领了直流电机以及相关控制设备的发展。 大多数与电机运行相关的早期科学发现主要涉及直流系统。不久之后，交流电的发电和传输推广开来。转变到交流发电和传输的主要原因是变压器被用来提升交流电压以便于远距离传输电力。因此，变压器的发明使得发电和电力传输从直流向交流变换成为可能。目前，几乎所有的电力系统产生和传输的都是三相交流电。变压器使得由交流发电机产生的电压被升高而电流相应地被减小。这一切使得在一个降低了的电流水平上进行长距离的电力传输，减小了功率损失，而提高了系统的效率。 电机广泛应用于家用电器、工业和商业上，用于驱动机器和复杂的设备。许多机器和自动化设备需要精确控制。因此，自从早期应用于火车的直流电机以来，电机设计和复杂性已经发生了变化。电机控制方法已经成为关系机器和设备运行效率的至关重要的因素。一些创新，例如伺服控制系统和工业机器人已经引领了电机设计的新的发展方向。 我们复杂的交通系统也对电机的应用产生了影响。汽车和其它地面交通工具用电动机作为点火启动系统，用发电机作为电池充电系统。电动汽车成为最近的研究热点。飞机应用电机的方式与汽车相似，然而，在实际应用中，飞机上采用了复杂的同步电机和伺服控制电机。 5.2 电机的基本结构 旋转电机实现了电能-机械能之间的转换。发电机将机械能转换成电能，而电动机将电能转换成机械能。发电机和电动机具有相同的基本结构特点，这一点对于大多数类型的电机来说是一致的。虽然多种电机在结构上是相同的，但是，它们的功能是不同的。发电机的旋转运动由提供机械能输入的原动机提供。导体和发电机磁场之间的相对运动产生电能输出。电动机将电能施加到其绕组和磁场上，形成电磁感应作用，产生机械能或力矩。 大多数旋转电机的结构具有某种程度的相似性，多数电机具有一个静止的部件称为定子，而旋转的一组导体称之为转子。定子由轭或机壳组成，用于支撑和构成磁通的金属回路。 5.2.1磁极与绕组 旋转电机具有磁极，他们是电机定子的一个组成部分。磁极由钢片叠制而成，并且与机壳是绝缘的，在靠近转子的部分是弯曲的，用于提供低租的磁通回路。磁场绕组或磁场线圈被置于磁极周围。这些磁场线圈构成了电磁铁，用来与转子产生电磁场相互作用，从而产生感生电压或在电动机中产生力矩。 5.2.2转子结构 在电机的研究中，需要理解由电动机或发电机的旋转部分产生的电磁场，该旋转部分称为电枢或转子。一些类型的电机采用坚固的金属转子，成为为鼠笼式转子。 5.2.3滑环、开口环和电刷 为了将电能施加到旋转装置上，例如电枢，一些滑刷接触必须建立起来。滑刷接触可以是滑环，也可以是开口环。滑环由绝缘的圆柱形材料构成，其上粘贴两块分开的固态金属环，滑动电刷由碳或石墨制成，放在金属环上，在旋转过程中，向滑环施加或抽取电能。开口环换向器与滑环相似，只不过该金属环被分成两个或更多个独立的部分。作为一个基本原则/惯例，滑环用于交流电动机和发电机，而开口环用于直流电动机。开口尽可能地小，以减少碳刷的火花。滑环和开口环如图5.1所示。 5.2.4其它电机部件 在旋转电机的结构中，还用到其它几个部件。其中有电机轴，在一组轴承上进行旋转。轴承可以是滚珠轴承、滚柱轴承或轴套轴承。轴承密封通常是由毡类材料制成，用于保持轴承润滑和防止灰尘进入。转子芯通常由叠制的钢片组成，以在磁极之间提供低磁阻的磁通回路，并有利于减小涡流。内部和外部接线柱提供了传入或传出电能的途径。 5.3 电动机的结构特点 在现有的电子机械装置中，能量转换过程通常有两个重要特点。有磁场绕组，用以产生磁通密度，还有电枢绕组，产生起作用的感生电动势。在本小节中，将描述主流类型电动机的突出结构特点，揭示这些绕组的位置、并展示这些电机的基本组成部分。 5.3.1 三相感应电动机 这是一种工业上最耐用、应用最广的电动机。它的定子有高规格的钢片叠制而成，内表面开槽用于安放三相绕组。
大学英语（1）第二次网络作业 (三次网络作业的平均成绩占期末考试成绩30%，请大家在认真复习好《大学英语》课本第一册第3-4单元的课文、词汇与短语后完成如下作业；作业一经批改评分，将不能修改；此次作业完成后应交到“在线作业”一栏本次作业界面中；作业必须按最后一页答卷表格格式作答，不要以附件形式缴交) 一. 阅读： （ 1 ） The angry woman stood by the station. “ The railway owes me ￡12,”she said to Harry Jenks, the booking clerk (订票员). “My ticket was for May 22nd, and there was no ship from Jersey that night. My daughter and I had to stay in a hotel. It cost me ￡12.” Harry was worried. He remembered selling the woman a return ticket. “Come into the office, madam,”he said, “ I’ll just check the Jersey timetable for May 22nd .” The woman and her little girl followed him inside. She was quite right, as Harry soon discovered. There was no sailing on May 22nd. How ever had he made such a big mistake? Wondering what to do, he smiled at the child. “You look healthy,” he said to her. “ Did you have a nice holiday in Jersey?” “Yes,”she answered. “The beach was beautiful. And I can swim too!” “ That’s fine,” said Harry. “ My little girl can’t swim a bit yet. Of course, she’s only three-----” “ I’m four,” the child said proudly. “ I’ll soon be four and a half.” Harry turned to the mother. “ I remember your ticket, madam,”he said. “But you didn’t get one for your daughter, did you?” “Er, well-----”The woman looked at the child. “I mean-----she hasn’t started school yet. She’s only four.” “A four year old child must have a ticket, madam. A child’s