Resistor and resistance
A resistor is an electrical component that limits or regulates the flow of electrical current in an electronic circuit. It is the simplest sort of electrical component. It is used in a circuit for protection and current control. A resistor has two terminals across which electricity must pass, and is designed to drop the voltage of the current as it flows from one terminal to the next.
Resistors can fall into two categories: fixed or variable. A fixed resistor has a predetermined amount of resistance to current, while a variable resistor can be adjust to give different levels of resistance. Variable resistors are also called potentiometers (电位计) and are commonly used as volume controls on audio devices. A rheostat(可变电阻器) is a variable resistor made specifically for use with high currents. There are also metal-oxide varistors(变阻器）,which change their resistance in response to a rise in voltage; thermistors(热敏电阻），which either raise or lower resistance when temperature rises or drops; and light-sensitive resistors.
Every resistor has resistance. Resistance is a feature of a material that determines the flow of electric charge. The unit of resistance is ohm. In a direct-current (DC) circuit, the current through a resistor is inversely（相反地）proportional to its resistance ,and directly proportional to the voltage across it. This is the well-known Ohm's Law. It can be written in an equation V=IR, where V is voltage, I is current, and R is resistance. A high ohm rating indicates a high resistance to current. In alternating-current (AC) circuits, this rule also applies as long as the resistor does not contain inductance or capacitance. Resistance can be written in a number of different ways depending on the ohm rating. For examples ,81R represents 81 ohms, while 81K represent 81,000 ohms.
The resistance varies in different material. For example, gold, silver, and copper have low resistance, which means that current can flow easily through these materials. Glass, plastics, and wood have very high resistance, which means that current can not pass through these materials easily.
Resistors can be fabricated in a variety of ways. The most common type in electronic devices and systems is the carbon-composition resistor. Graphite (石墨) is mixed with clay (泥土) and hardened. The resistance depends on the proportion of carbon（碳）to clay; the higher this ratio, the lower the resistance.
Another type of resistor is made from winding nichrome (镍铬铁合金) or similar wire on an insulating form. This component, called a wirewound (线绕的）resistor, is able to handle higher currents than a carbon-composition resistor of the same physical size. However, because the wire is wound (缠绕) into a coil, the component acts as an inductors as well as exhibiting resistance. This does not affect performance in DC circuits, but can have an adverse effect in AC circuits because inductance renders (使得）the device sensitive to changes in frequency.
The amount of resistance offered by a resistor is determined by its physical construction . A carbon composition resistor has resistive carbon packed into a ceramic cylinder（陶瓷柱体）, while a carbon film resistor consists of a similar ceramic tube, but has conductive carbon film wrapped around the outside. Metal film
or metal oxide resistors are made much the same way, but with metal instead of carbon. A wirewound resistor, made with metal wire wrapped around clay, plastic, or fiberglass tubing, offers resistance at higher power levels. For applications that must withstand high temperatures, materials such as cermets, a ceramic-metal composite, or tantalum, a rare metal, are used to build a resistor that can endure heat.
A resistor is coated with paint or enamel（瓷漆）, or covered in molded plastic to protect it. Because resistors are often too small to be written on , a standardized color-coding system is used to identify them. The first three colors represent ohm value, and a fourth indicates the tolerance, or how close by percentage the resistor is to its ohm value. This is important for two reasons: the nature of resistor construction is imprecise, and if used above its maximum current, the value of the resistor can alter or the unit itself can burn up.
1.Choose the best one that best suits the sentence according to the text.
(1)When the voltage flows across the resistor, the voltage will B .
A. rise
B. drop
C. no variation
D. all of the above are possible
(2)Variable resistors are also called B .
A. Varistors
B.potentiometer
C. thermistor
D. metal oxide resistors
(3)In a direct-current circuit, when the voltage is fixed, as the current through a resistor is higher, this shows that its resistance is A .
A. lower
B.higher
C. the same
D. all of the above are possible
(4)Compared with copper, the ceramic is A .
A. less conductive
B.more conductive
C. more inductive
D.less inductive
(5)When the proportional of clay to carbon is higher, the resistance will be
A .
A.lower
B.higher
C.no effect
D.all of the above
(6)For applications that must withstand high temperatures, we can use D .
A.cermet
B.ceramic-metal composite
C.tantalum
D.all of the above
2.Translate the text.
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。
一．单词翻译(英译汉，汉译英共20分） compound pulley 组合滑轮 screw 螺丝 worm gear 涡轮 clearance fit 间隙配合 transition fit 过渡配合 interference fit 过盈配合 ground teeth 精密齿 gear reductions 齿轮减速比aluminum 铝 brass 黄铜 bronze 青铜 cast iron 铸铁 carbon 碳钢 alloy steel 合金钢 hardened steel 硬化钢 stainless steel 不锈钢 plastic materials 塑料材料 gear teeth 齿轮 straight-toothed 直齿轮 rack and pinion 齿条和齿轮 straight bevel gears 直齿锥齿轮spiral bevel gears 弧齿锥齿轮friction 摩擦 lubrication 润滑 lubricant 润滑剂 full fluid film lubrication 全液态薄膜润滑 boundary lubrication 边界润滑elastrohydrodynamic lubrication 流体弹性动力润滑 proton 质子 neutron 中子 parallel circuit 并联电路 series circuit 串联电路 electron 电子 inductor 电感 capacitor 电容 conductor 导体 semiconductor 半导体 metal-oxide-semiconductor 金属氧化物半导体 integrated circuit 集成电路integrated circuit chip 集成电路芯片 dopant 掺杂剂 mask 掩膜 doping 掺杂 photoresist 感光胶 etch 蚀刻法 dielectric 非传导性（电介质）rung 梯级 branch 分支 instructions 指令 power rails 母线 quantity 数量 parameter 参数 ladder diagram 梯形逻辑图 ON-delay timer 通电延时定时器OFF-delay timer 断电延时定时器retentive timer 保持定时器proximity timer 接近开关electromechanical control 机电控制mobile robots 可移动机器人manipulator robots 操作机器人 self reconfigurable robots 自变形（重装）机器人 Analog-to-Digital Converter A/D模数转换器 Digital-to-Analog Converter D/A模数转换器 ASIC(Application Specific Integrated Circuit)专用采集电路 Laplace transform 拉普拉斯变换 Z-transform Z变换 valve 阀 pump 泵 motor 发动机 cavitation 气穴 hydraulic 液压的 equilibrium position 平衡位置vibration(oscillation) 振动transducer 饱和电抗器,传感器，变频器 reservoir 油箱 pump with electric motor 电力马达泵unloader and safety relief valve 减荷
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.
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《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。
四川理工学院成人高等教育 《机电工程专业英语》试卷（ A 卷） 年级三年级 专业机电一体化 ZK931101 层次专科 号 题号一二三四五六七八总分评阅(统分)人 学 题分20 30 20 30 得 分 注意事项： 线 名 1.满分 100 分。要求卷面整洁、字迹工整、无错别字。 姓 订 生 2.考生必须将“学生姓名”和“学号”完整、准确、清楚地填写在试卷规定的地方，否则视为 学 装 此 废卷。 过 3.考生必须在签到表上签到，否则若出现遗漏，后果自负。 要 得分 评阅教师 级 不 一、选择题： 班 题 业 专 答 选择括号中提供的单词或短语，并以正确的形式填空。 （每空 2 分，共 20 分） ( send out, focus on, deny, prove, make sure, equip with, shock, accomplish, vary from, call ) （ 1） A week ago he received a notice stating his application was . （ 2） Effective teaching is the learning needs of each student in the class. （ 3） His mother when she heard about the accident. ) （ 4） He a number of e-mail messages to his friends. 班 （ 5） Position measurement in NC machines 属 can through direct or indirect methods. 直 ( （ 6） The actual programming commands needed will 点 also builder to builder. 学 （ 7） This method to be very successful. 教 （8） that the instructions for the use of this high pre are strictly observed. （9） The majority of NC/CNCmachine tools automatic too such as magazines on machining center and turrets on turning centers. （10） The movements are detected and counted by a feedback device a transducer. 得分 评阅教师 二、名词解释： 写出下列英文缩写的全称 ,并翻译成中文。 （每题 3 分，共 30 分） （ 1） PLC （ 2） CIM （ 3） AGV （ 4） FMS （ 5） ROM （ 6） CPU （ 7） CNC （ 8） CAD （ 9） GUI （ 10） JIT 得分 评阅教师 三、汉译英： 将下列术语翻译成英文。 （每题 2 分，共 20 分） （ 1） 在线编程 （ 2） 装配有（某设备） （ 3） 钻床 （ 4） 齿轮加工 （ 5） 穿孔纸带 （ 6） 切削中心 （ 7） 加工中心 （ 8） 光电开关 （ 9） 显示面板 （ 10） 超声波加工 得分 评阅教师 四、英译汉
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/ce17688206.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．, . (√)
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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”。
Unit 1 原子钟 电子或电子计时装置是由原子或分子的震荡控制的。一个计时装置必须包含或者连到一些均匀震荡的的仪器上来控制指针的移动的频率或者数字改变的频率。机械钟或者手表利用震荡平衡轮，钟摆和音叉。更高的精度或许利用原子或分子震荡，因为这种震荡频率如此高，不肯能用他们做控制时钟的直接手段.。然而，这种钟被一种高速平稳输出可以自动增加而且可以与原子系统的比较的晶体振荡器控制。这种震荡器的错误会自动改正。时间通常是由数字原子时钟或者其他的复杂的读数设备显示的。 第一个原子时钟，发明与1948年，利用氨分子的振动。一对这样的时钟之间的误差，也就是说，在指定的时间如果两者统一瞬间启动然后比较,区别通常是三千年差一秒。在1955年，第一个铯束时钟（一种利用铯原子发射精密频率的微波光谱线作为参考的设备），在英国的特丁顿国家物理实验所投放操作。美国的标准是nist f-1，他是在1999年进入服务的并且在两千万年里不会快或者慢一秒。一个喷泉原子钟，NIST F-1原子钟包含由高3英尺的垂直管的内部结构.他用激光冷却铯原子，在空气中用激光摇匀形成铯原子团。特别像一个摇匀的网球。形成喷泉效果。这允许原子比以前的任何时钟都要观察的远。 许多世界国家的标准实验室保存着原子钟，用这些时钟平均产生叫TAI的标准来维持时间。高精度的时间信号是来源于这些标准实验室通过短波无线广播站或者人造卫星向全世界传播的。这种信号被用来跟踪太空飞行器，电子导航系统和地壳的瞬间的研究等事情。这些精确的时钟使利用实验证明了一个很大的预言-爱因斯坦的相对论成为可能。原子钟的原型是用氢原子或者铍原子这样的原子可以几千年仍可以很准确。比如：美国家标准与技术研究院的研究人员已经证明过渡在一个基于能源困汞离子（汞原子丢失了一个电子）的时钟潜在着比目前时钟精确度高达1000倍。 Unit 2 制动（刹车）系统 制动（刹车）踏板或者用手杆来激活（启动）刹车（制动），对于低功率的机器或者车，操作人员通常可以提供足够的力通过一个简单的机械运动把刹车踏板或者操作杆联系到刹车的部分上。然而，大多数情况下，这种力可以通过一种精心制作的系统来增加。 空气制动系统 空气制动系统是一种早期的系统用来增加制动力，也可以叫做空气制动，它是由美国乔治西屋的制造商发明的并与1868年第一次使用在乘客火车上。现在他被广泛应用在铁路火车上。它的基本原理是利用压缩运动空气使油箱的活塞安放在车轮上的闸块式制动器。动作同时作用在火车车厢的轮子上。通过连轴器连接的车厢之间通过用结实的管子传递空气。与此同时，通过工程师控制他释放在所有的单独的闸块式制动器部位。在制动管损坏，泄露或者是刹车部位损坏，它有自动提供所有闸块式刹车设置。空气制动系统也被应用在地铁，有轨电车，公共汽车和卡车。
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
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