大学科技英语课文例句和课后部分答案
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Main Content: UNIT 1 MATHEMATICSI.Text OrganizationParts ParagraphsMain IdeasPart One Paras. 1-3 Game theory can be defined as the science ofstrategy which studies both pure conflicts(zero-sum games) and conflicts in cooperativeforms.Part Two Paras.4-11 There are two distinct types of strategic interdependence: sequential-move game and simultaneous-move game.Part Three Paras.12-19The typical examples of game theory are givenas the basic principles such as prisoners’dilemma, mixing moves, strategic moves,bargaining, concealing and revealinginformation.Part Four Para. 20 The research of game theory has succeeded inillustrating strategies in situations ofconflict and cooperation and it will focus onthe design of successful strategy in future. nguage PointsThe games it studies range from chess to child rearing and from tennis to takeovers. (Para.1)Paraphrase: The games it (game theory) studies extends from chess to child bringing-up and from tennis to handovers.range: v. to vary between limits, extend, run in a linee.g. (1) The price ranges from $ 30 to $ 80. (2) The boundary ranges from north to south.takeover: n. the act or an instance of assuming control or management of or responsibility for sth. 接收、接管e.g. The economy of Hongkong goes well after its takeover. Game theory was pioneered by Princeton mathematician John von Neumann. (Para.2)pioneer: v. to be a pioneer; to originate (course of action etc., followed later by others)e.g. The new treatment for cancer was pioneered by the experts of state hospital.pioneer: n. original investigator of subject or explorer or settler; initiator of enterprisee.g. The young generation was greatly motivated by the pioneers’exploits.That is, the participants were supposed to choose and implementtheir actions jointly. (Para.2)Paraphrase: That is, the players were expected to select and carry out their actions together.…he must anticipate and overcome resistance to his plans. (Para.3) anticipate: v. 1) to expect or realize beforehand; to foresee e.g. The experts are anticipating the negative effects of air pollution.anticipate: v. 2) to deal with or use before proper time 预支e.g. Ted was not used to saving monthly and he would always anticipate his income.The essence of a game is the interdependence of player strategies. (Para.4)Paraphrase: The key principal of a game is that player strategies are dependent on each other.essence: n.1) the quality which makes a thing what it is; the inner nature or most important quality of a thinge.g. The two things are the same in outward form but different in essence.essence: n. 2) extract obtained from a substance by taking out as much of the mass as possiblee.g. milk essence; essence of peppermint (椒薄荷、椒薄荷油) interdependence: n. the quality or fact of depending on each otherinter-为前缀,意为between each other, 类似的词还有interchange、intermarry、international、interview等。
1.把激光射束射向地球Laser beams are emitted at the moon2.这个模型描述了原子的情况This model is descriptive of the behavior of an atom3.那位教授将做有关移动通讯方面的讲座That professor will deliver a lecture on mobile communication4.她给本科生上C++程序设计语言课She gives undergraduates lessons in the C++programming language5.这些学生在做物理实验These students are making an experiment in physics6.他们在做电学实验They are doing an experiment on electricity7.该教授对沃氏函数的研究起了重要作用The professor has played an important role in the research on the Walsh Functions8.无线电波朝四面八方传播Radio waves travel in all directions9.为此,我们必须在负载两端接一个电容器For this purpose,we must connect a capacitor across the load10.在这个温度上该金属就会融化At this temperature the metai will melt11.该专家将在会议上宣读一篇重要的学术论文The expert will read an important academic paper at the conference12.速度等于距离与时间之比Speed is the ratio of distance to time13.太阳离地球的距离是很远的The distance of the sun from the earth is very great14.温度对金属导电率的影响是很小的The effect of temperature on conductivity of metals is small15.本节论述晶体管与电子管相比的优点This section deals with the advantages of transistors over electron tubes16.重力加速度随纬度的变化,部分原因是由于地球的自转The variation of g with latitude is due in part to the earth’s rotation17.Y对x的依从关系用y=f(x)表示The dependence of y on x is expressed by y=f(x)18.人们用椭圆来描述行星绕太阳的运行情况Ellipses are used to describe the motions of the planets around the sun19.我们讨论了电流通过酸碱盐溶液的情况We have discussed the passage of an electric current through liquid solutions of acids,bases,and salts20.物体对净力F的影响就是正比于F的加速度a The response of a body to a net force F is an acceleration a proportional to F21.把式(4)与式(6)相比较,我们就能的得到一下几个关系式A comparison of Eq.(4)with Eq.(6)Leads to the following relations22.我们可以把一个力分解成x和y分量The resolution force into x and y components is possible23.应避免使人体接触有潜在毒性的物质Exposure of the body to potentially toxic substances should be avoided24.这些特殊问题是有把原子能用作为能源而产生的These special problems arise from the use of atomic energy as a source of power25.把电流定义为电荷的运动对我们大家都是熟悉的The definition of an electric current as the flow of electric charge is familiar to all of us26.哥伦布发现美洲是在哪一天What is the date of the discovery of America by Columbus27.爱因斯坦确立了相对论是20世纪最重要的事件之一The formation of the theory of relativity by Einstein is one of the most significant events of the 20th century 28.门捷列夫于1869年发现了周期表使人们有了计算原子质量的另一种方法The discovery of the periodic table by Mendeleev in 1869 suggested another way of estimating atomic masses29.这个工厂和那个一样大The factory is as large as that one30.铜的导电能力几乎和银一样好Copper conducts electricity almost as well as silver31.这台计算机的体积是一台打印机的3倍The size of this computer is there times as large as that of a typewriter32.那根导线长达100米That wire is as long as 100meters33.这根导线不如那根长This wire is not as long as that one(is)34.这台计算机的性能不如那台好This computer dose not work so well as that one35.导线越长,电阻越大The longer the wire ,the greater the resistance36.电压越大,电流就越大The greater the voltage,the larger the current37.电流越大,在导线中产生的热量就越多The larger the current,the more heat will be produced in the wire38.你学习越努力,你的进步就会越大The harder you study ,the greater progress you will make39.在无线电接收机中,一部分功率转变成了声波In a radio receiver,some power is converted to song waves40.绝缘体可以被用在导体之间来防止电流在他们之间流动Insulators may be used between conductors in order to prevent the flow of electric current between them41.把理论应用于实践是非常重要的To apply theory to practice is very important42.制作这样的电感器需要许多这样的线匝和铁芯To construct such inductors requires many turns of wire and iron cores43.现在能够把太阳光直接转变成电It is now possible to convert sunlight directly into electricity44.我们似乎能求出这个电流It seems possible to find out this current45.操作这台机器并不是件容易的事It is not an easy job to operate this machine46.做实验是极为重要的It is of great importance to make experiments47.解这个方程将要花费我们许多时间It will take us a lot of time to solve this equation48.我们发现用弧度而不是用度数表示角度是比较方便的It is found convenient to express angles in radians rather than in degrees49.当电流流过电路时,要损耗掉一部分能量Flowing through a circuit,the current will lose part of its energy50.若已知电流和电阻,我们就能求出电压Given current and resistance,we can find out voltage51.由于铜具有大量的自由电子,所以它是良导体Having a large number of free electrons,copper is a good conductor52.若用公式表示的话,电路中的电压,电流,电阻之间的关系可写成V=IR Expressed in a formula,the relationship between voltage,current and resistance in a circuit can be written as V=IR53.由于铜是电的良导体,所以被广泛的用在电工技术中Being a good conductor of electricity,copper is widely used in electrical engineering54.银是最好的导体,其次是铜Silver is the best conductor,followed by copper55.Σ是希腊字母“西格玛”,它的意思是“...之和”Σis the Greek letter sigma,meaning“the sum of”56.当机车拉着火车跑时,它就会做功A locomotive does work while pulling a moving train57.将物体置于水中,就会感觉到他比较轻When placed in water,everything will be found lighter58.这一设备,如果设计得当就可以用无线电控制This device,properly designed,can be controlled by radio59.当把雷达信号发向月球时,由于月球是固体,所以能反射信号When radar signals are sent to the moon,the moon,being solid,reflects them60.若该电流发生变化,磁场也将变化This current changing,the magnetic field will change as well61.若其他情况相同,电阻将正比于导体的长度Other things being equal,the resistance is directly proportional to the length of the conductor62.当阳光照在光电电池上时,该设备就会自动工作起来The sunlight falling upon photo-electric cells,the device will automatically go into operation63.由于原子很小,所以我们看不见它们Atoms being extremely small,we cannot see them64.几乎所有的金属都是良导体,而银为最好Almost all metals are good conductors,silver being the best65.每当导体内的电流发生变化时就会在到体内感应出一个电动势,因而这种电动势就成为自感电动势Whenever there is a change of current in a conductor,an emf is induced in the conductor,thus this kind of emf being called a self-induced emf 66.银在金属中电阻率最低,而铜的电阻率比他高不了很多Silver has the smallest resistivity of any metal,with that of copper not much greater67.若电路中没有电阻,电流就会无限增大With no resistance in the circuit,the current would increase forever68.我们周围的一切东西均是物质这一事实是大家都知道的The fact that everything around us is matter is known to all P(127)69.在这种情况下,该函数必须存在这一条件并没有满足In this case ,the condition that the function must exist is not satisfied70.等式只是某个量等于另一个量的一种陈述An equation is simply a statement that a certain quantity ia equal to another one71.欧姆观察到这一事实:如果电压保持不变,则电阻越大,电流就越小Ohm observed the fact that if the voltage remains the same,the greater the resistance,the smaller the current72.质子和电子之间所观察到的作用力,就导致了大家所熟悉的说法;同种电荷相互排斥,一中电荷相互吸引The observed forces between protons and electrons then lead to the familiar statement that like charges repel one another,unlike charges attract one another73.这些实验用来证实吉尔伯特的结论:电荷有两种There experiments serve to confirm Gilbert's conclusion that there are two kinds of electric charge74.电子学的诞生,是从发现了真空二极管中的电流,可以通过引入第三个电极来加以控制这个时候算起的The advent of electronics is reckoned from the discovery that the current in a vacuum diode can be controlled by introducing a third electrode75.十九世纪科学上最显著的成就之一是人们认识到了光是由电磁波构成的Among the most noteworthy achievements of 19th century science was the realization that light consist of electromagnetic waves76.现在人们越来越认识到这些技术在诸如控制系统和仪表测量这样的领域中也是很有价值的There is a growing awareness that these techniques are also of value in such areas as system control and instrumentation77.这两个带电球之间的斥力表明具有同种电荷的物体相互排斥The repulsion between these two charged balls is evidence that bodies having like charges repel each other78.由图2可以看出这一现象与反射有关That this phenomenon has connection with reflection may be seen from Fig.2 P(137)79.每个电路的工作原理在这一章进行了详细的讨论How each circuit works is discussed in detail in this chapter80.我们用哪个式子,将取决于在题目中给出了那些数据Which equation we want to use will depend on what data we have been given in a problem81.我们可以用计算机解决这些复杂的题目It is possible that we use a computer to solve these complicated problems82.有趣的是,每个函数均可用一些简单函数来近似It is interesting that every function can be approximated by simply functions83.那个问题是如何解决的还是个谜It is a mystery how the problem was solved84.众所周知我们周围的一切东西均为物质It is known that everything around us is matter85.在很久以前人们就发现电流的方向与电子的方向相反It was found long ago that the direction of the current is just opposite to that of the electron flow86.我们已经知道接收到的信号一般是很微弱的,其通常的功率约为几皮瓦It has been known that the signal received is generally quite weak,powers of the order of picowatts being common87.尚不了解有那些因素决定这种灯丝的尺寸It is not yet understood which factors determine the size of filaments of this kind88.我们无法预言这种现象何时发生It cannot be predicted when this phenomenon will take place89.朝哪个方向运用NPN晶体管基本上是没什么区别的It does not basically make any difference in which direction an NPN transistor is operated90.我们知道磁场能对电流施加一个力We have known that a magnetic field is able to exert a force on an electric current91.我们可以说物体的能量就是物体做功的能力One may say that the energy of a body is the ability of that body to do work92.我们往往想要知道这一误差是否可以忽略不计We often want to know whether this error may be neglected93.事实是无线电波的传播速度和光速一样The fact is that radio waves travel as fast as light dose94.其结果将是在导线两端之间将会存在这种电位差The result will be that this potential difference will exist between the ends of the conductor95.温度是与物体的体积无关的一种物质性质Temperature is a property of the body not concerned with how large the body is96.上面所讲的就是欧姆定律What has been described is Ohm's law97.我们能够学会我们原来不懂的东西We can learn what we did not know98.计算机能够做人们告诉它要做的事A computer can do what it has been told to do99.发电机的功能是把机械能转换成电能What a generator dose is convert mechanical energy into electrical energy100.作用在载流导线上的磁力就是使电机工作的力The magnetic force on current-carrying wires is what makes electric motors work101.我们想要获得对于A、B两点之间所发生的情况的详细描述We wish a detailed picture of what happens between points A and B102.所得到的是同样的那些表达式What result are the same expressions103.这个能量就是给自感电动势供能的能量This energy is what powers the self-induced emf104.众所周知(的是)光是一种电磁波What is well know is that light is a kind of electromagnetic wave105.这就是我们通常所说的力This is what we call a force106.电子计算机能懂得所谓的机器语言The electronic computer is able to understand what is known as the machine language107.电流随所谓的电阻变化Current changes with what is described as resistance 108.反射回来的那部分电流形成了所谓的回波信号The reflected portion of waves forms what is referred to as the echo signal109.存在有许多自由电子的物质被称为导体The substance in which there are many free electrons is called a conductor110.电流流过的闭合通道被称为电路The close path though which current flows is referred to as the electric circuit111.电动机是把电能转换成机械能的一种机器An electric motor is a machine by which electric energy is chang into mechanical energy112.存储电荷的器件称为电容器The devices on which charges are stored are called capacitors113.光传播的速度是极快的The spend at which light travels is extremely great 114.用来把热能转换成功的任何机械装置均称为热机Any mechanical device by means of which heat is converted into work is called a heat engine115.惯性是物质的一种特性,由于这种特性,要使物体加速就必须对该物体施加一个力Inertia is that property because of which a force must be exerted on a body in order to accelerate it116.正如标题所示本章论述数字计算机的原理As the title indicates,this chapter deals with the principles of digital computers117.我们知道,电子是微小的负电荷Electrons,as one knows,are minute negative charges of electricity118.我们已讲过晶体管是电流控制器件As has been described,transistors are current-control devices119.晶体管体积小效率高这是大家所熟知的Transistors are small & efficient,as is well known to us120.顾名思义流体是一种容易流动的物质Fluid,as the name shows,is a substance that flows readily121.一根导线可用作为天线A wire can serve as an antenna122.作为通讯工具,卫星是最先进的As a means of communication,a satellite is the most advanced123.能量被定义为物体做功的能力Energy is defined as the ability of a body to do work124.我们把g这个量定义为重力加速度We refer to the quantity g as gravity125.一个常数无论有多大,均不可能称为无穷大A constant number,no matter how large it may be,is never spoken of as infinite126.把能量定义为物体做功的能力是合理的The definition of energy as the ability of a body to do work is reasonable127.当电流流动时电池的能量就给电阻消耗了As the current flows,energy from the battery goes to the resistance128.两物体间的万有引力,随他们之间的距离的增加而减弱The force of gravitational attraction between two bodies decreases as the distance between them increases129.由于空气有重量所以它对处于其中的任何物体均要施加一个力As air has weight,it exerts force on any object immersed in it130.电子绕原子核旋转,就像行星绕太阳运行一样Electrons move round the nucleus just as the planets moves round the sun131.这台计算机与那台一样重This computer is as heavy as that one(is)132.原子虽小,却是由一些更小的单元组成Small as they are,atoms are made up of still smaller units133.正如早已证明的那样,若使负的各项变为正,该级数就发散If the negative terms are made positive the series becomes divergent,as has been shown already 134.我们必须记住用以表示化学元素的那些符号We must remember such symbols as are used to represent chemical elements135.我们也可以用计算机解这道题A computer can be used as well to solve this problem136.我们能求出流过这个电阻的电流及两端的电压It is possible to find out the current through this resistor as well as the voltage across it137. 这台计算机的工作性能与那台一样好This computer works as well as that one dose138.数学是一种非常有用的工具,因此它广泛用在工程的各个领域之中Mathematics is a very useful tool.As a result,it is widely used in various fields of engineering139.只要外加电压保持不变在电路中流动的电流与该电路中的电阻成反比The current flowing in a circuit is inversely proportional to the resistance in the circuit as long as the applied voltage remains constant140.若地面没有摩擦,就不可能停止任何物体的运动Were there no friction on the ground,it would be impossible to stop the motion of any body141..若电压不那么高的话,那台仪器也就不会被烧坏了That instrument would not have been damaged had the voltage not been so high142.如果在导线中有很强的电流,那么只要用一匝大号导线就可以制成磁性很强的电磁铁A powerful electromagnet can be made with only one turn of a large-sized wire,should a very large current flow in the wire143.若没有地球的引力,地球上的一切东西都要失重Everything on the earth will lose its weight provided there be no gravity144.若没有半导体,就不可能有卫星通讯这类事情Some things,like satellite communications,would be impossible without semiconductors145.要不是二进制,电子计算机可能要比现在复杂得多But for the binary system,the electronic computer might have been much more complicated146.我们本来可以用定理(6)来导出式(5)We could also have used Theorem(6)to derive equation(5)147.为了使电流在电路中流动,必须保持一个电位差It is necessary that potential difference be maintained for current to flow in a circuit148.数字电路设计人员必须很熟悉布尔代数的实用知识It is essential that the digital designers should have a good working knowledge of Boolean algebra149.我们希望机器都不要有能量消耗It is desired that any machine have no energy loss150.有人建议在太空制造药物It is suggested that drugs be made in space151.我们建议读者最好用袖珍计算器来做基础电子学中的所需的数学计算It is recommended that the reader use a pocket calculator to do mathematical work required in basic electronics152.经济方面要求电力以高压传送Economy demands that electric power be transmitted at high voltage153.实验要求测量应精确Experiments require that accurate measurements be made 154.我们建议把这一点接地Our suggestion is that this point be grounded155.这是由于输出必须稳定的原因This comes from the necessary that the output be stable156.这根传输线的作用就好像它是开路似的This transmission line acts as though it were open-circuit157.在这种情况下金质叶片就会散离开来,就好像它们由通过接触而起电的物体而带电一样Under this condition the gold leaves will diverge just as if they had been charged from a body electrified by contact158.电位差使电流在电路中流动The potential different causes an electric current to flow in the circuit159.正是电位差使得电流在电路中流动It is the potential difference that causes as electric current to flow in the circuit160.物体的惯性质量与重力质量是成正比的,这是一个极为重要的实验事实It is very significant empirical fact that the inertial and gravitational masses of a body are proportional to each other161.是硬件在很大程度上确定了该系统的能力It is the hardware which determines to a large degree the capabilities of the system162.正是这些优点使阿拉伯数字为全世界人们所接受It is these strong points that make the Arabic figures accepted by people all over the world163.直到1925年才证实了电离层的存在It was not until 1925 that the existence of the ionosphere was proved164.是法拉第首先发现了电磁感应现象It was Faraday who first discovered electromagnetic induction165.正是这些力导致产生了磁现象It is these forces which lead to magnetic phenomena166.天平所度量的实际上是质量不是重量It is actually mass not weight which the balance measures167.正是在那儿发射了第一颗卫星It was there that the first satellite was launched 168.正是在这个意义上数学有时被称为科学的语言It is in this sense that mathematics is sometimes called the language of science169.正是当导线切割磁力线时在导体上感应出一个电动势来It is when lines of force are being cut by the wire that an emf is induced in it170.并不是科学家使用的工具而是他使用工具的方法使他成为科学家It is not the tool a scientist uses but how he uses these tools that makes him a scientist171.没人知道到底是什么东西构成了场本身No one knows what it is that composes the field itself172.大多数数字电路是与其它数字电路对接的。
(整理后)科技英语部分课后答案第一单元第8页1. processing speed 处理速度2. user-friendly interactive graphics 用户友好的交互图形3. product cycle 产品周期4. design specification 设计规格5. design evaluation 设计评价6. 计算机辅助设计CAD7. 计算机辅助制造CAM8. 计算机辅助工程CAE9. 设计过程design process10. 制造过程production process翻译句子(考5个)1. Today’s industries cannot survive worldwide competition unlessthey introduce new products with better quality(quality, Q), at lower cost(cost, C), and with shorter time delivery (delivery, D).除非能以较低的价格提供更好的质量及更短的交货时间提供新产品,否则任何企业都无法在当今的国际竞争中立足。
2.The design process starts from customers’ demands that areidentified by marketing personnel and ends with a complete description of the product, usually in the form of a drawing.设计过程始于由市场人员认定的用户需求,止于对产品的完整描述,通常用图形来表现。
3. The activities involved in the design process can be classifiedlargely as two types: synthesis and analysis.设计过程所涉及的活动大体分为两类:综合和分析4. An analysis model is derived first because the analysis subprocess is applied to the model rather than the design itself 首先要导出一个分析模型,因为分析子过程适用于该模型而非设计本身。
科技英语阅读课后参考答案-Unit1,3Unit 1 MathematicsPart I EST Reading Reading 1Warm-up Questions: Work in pairs and discuss the following questions. 1. Who is Bertrand Russell? Bertrand Arthur William Russell (b.1872 – d.1970) was a British philosopher, logician, essayist and social critic best known for his work in mathematical logic and analytic philosophy. His most influential contributions include his defense of logicism (the view that mathematics is in some important sense reducible to logic), his refining of the predicate calculus introduced by Gottlob Frege (which still forms the basis of most contemporary logic), his defense of neutral monism (the view that the world consists of just one type of substance that is neither exclusively mental nor exclusively physical), and his theories of definite descriptions and logical atomism. Russell is generally recognized as one of the founders of modern analytic philosophy, and is regularly credited with being one of the most important logicians of the twentieth century. 2. What is Russell’s Paradox? Russell discovered the paradox that bears his name in 1901, while working on his Principles of Mathematics (1903). The paradox arises in connection with the set of all sets that are not members of themselves. Such a set, if it exists, will be a member of itself if and only if it is not a member of itself. The paradox is significant since, using classical logic, all sentences are entailed by a contradiction. Russell's discovery thus prompted a large amount of work in logic, set theory, and the philosophy and foundations of mathematics. 3. What effect did Russell’s Paradox have on Gottlob Fregg’s system? At first Frege observed that the consequences of Russell’s paradox are not immediately clear. For example, “Is it always permissible to speak of the extension of a concept, of a class? And if not, how do we recognize the exceptional cases? Can we always infer from the extension of one concept’s coinciding with that of a second, that every object which falls under the first concept also falls under the second? Because of these kinds of worries, Frege eventually felt forced to abandon many of his views. 4. What is Russell’s response to the paradox? Russell's own response to the paradox came with the development of his theory of types in 1903. It was clear to Russell that some restrictions needed to be placed upon the original comprehension (or abstraction) axiom of naive set theory, the axiom that formalizes the intuition that any coherent condition may be used to determine a set (or class). Russell's basic idea was that reference to sets such as the set of all sets that are not members of themselves could be avoided by arranging all sentences into a hierarchy, beginning with sentences about individuals at the lowest level, sentences about sets of individuals at the next lowest level,1sentences about sets of sets of individuals at the next lowest level, and so on Using a vicious circle principle similar to that adopted by the mathematician Henri Poincaré, and his own so-called "no class" theory of classes, Russell was able to explain why the unrestricted comprehension axiom fails: propositional functions, such as the function "x is a set," may not be applied to themselves since self-application would involve a vicious circle. On Russell's view, all objects for which a given condition (or predicate) holds must be at the same level or of the same "type." 5. Have you ever heard of Zermelo-Fraenkel set theory.? Can you give an account of it? Contradictions like Russell’s paradox arose from what was later called the unrestricted comprehension principle: the assumption that, for any property p, there is a set that contains all and only those sets that have p. In Zermelo’s system, the comprehension principle is eliminated in favour of several much more restrictive axioms: a. Axiom of extensionality. If two sets have the same members, then they are identical. b. Axiom of elementary sets. There exists a set with no members: the null, or empty, set. For any two objects a and b, there exists a set (unit set) having as its only member a, as well as a set having as its only members a and b. c. Axiom of separation. For any well-formed property p and any set S, there is a set, S1, containing all and only the members of S that have this property. That is, already existing sets can be partitioned or separated into parts by well-formed properties. d. Power-set axiom. If S is a set, then there exists a set, S1, that contains all and only the subsets of S. e. Union axiom. If S is a set (of sets), then there is a set containing all and only the membersof the sets contained in S. f. Axiom of choice. If S is a nonempty set containing sets no two of which have common members, then there exists a set that contains exactly one member from each member of S. g. Axiom of infinity. There exists at least one set that contains an infinite number of members. With the exception of (b), all these axioms allow new sets to be constructed from already-constructed sets by carefully constrained operations; the method embodies what has come to be known as the “iterative” conception of a set. /doc/a90df7ed551810a6f524860e.html/entries/russell/ Section C Post-reading TaskReading Comprehension1. Directions: Work on your own and fill in the blanks with the main idea. Part 1 (Para. 1): Brief introduction to Russell’s paradox Part 2 (Paras. 2-5): The effect of Russell’s paradox on Gottlob Frege’s system.2Para. 2: Russell’s paradox dealt a heavy blow to Frege’s attempts to develop a foundation for all of mathematics using symbolic logic. Para. 3: An illustration of Russell’s paradox in terms of sets Para. 4: Contradiction found in the set. Para. 5: Frege noticed the devastating effect of Russell’s paradox on his system and inability to solve it. Part 3 (Paras. 6-8): Solutions offered by mathematicians to Russel’s paradox Para. 6: Russell’s own response to the paradox with his "theory of types."Para. 7: Zermelo's solution to Russell's paradox Para. 8: What became of the effort to develop a logical foundation for all of mathematics? Part 4 (Para. 9): Correspondence between Russell and Frege on the paradox 2. Directions: Work in pairs and discuss the following questions. 1) What is the basic idea of Russell’s paradox? 2) How to explain Russell’s paradox in terms of sets? 3) Can you explain the contradiction found in the sets related to Russell’s paradox 4) Is Russell’s own response to the paradox workable? 5) Do you know Zermelo-Fraenkel set theory? (open) 3. Directions: Read the following passage carefully and fill in the blanks with the words you’ve learned in the text. Russell's own response to the paradox came with the development of his theory of types in 1903. It was clear to Russell that some restrictions needed to be placed upon the original comprehension (or abstraction) axiom of naive set theory, the axiom that formalizes the intuition that any coherent condition may be used to determine a set (or class). Russell's basic idea was that reference to sets such as the set of all sets that are not members of themselves could be avoided by arranging all sentences into a hierarchy, beginning with sentences about individuals at the lowest level, sentences about sets of individuals at the next lowest level, sentences about sets of sets of individuals at the next lowest level, and so on. Using a vicious circle principle similar to that adopted by the mathematician Henri Poincaré, and his own so-called "no class" theory of classes, Russell was able to explain why the unrestricted comprehension axiom fails: propositional functions, such as the function "x is a set," may not be applied to themselves since self-application would involve a vicious circle. On Russell's view, all objects for which a given condition (or predicate) holds must be at the same level or of the same "type."Vocabulary and Structure31. Word-building Directions: Give the correct form of the word according to the indication in the brackets. Then complete the sentences using the right form for each word. Use each word once. discover— (suffix) logic— (suffix) correspond—(suffix) describe—(suffix) contradict— (suffix) symbol—(suffix) form—(suffix) develop—(suffix) able—(prefix) equal—(suffix)1) The math may not have been new, but Duchin enjoyed the process of_________, and she got to work collaboratively with half a dozen other math whizzes.( discovery) 2) Packages can be sealed and can contain personal _________if it relates to the contents of the package.( correspondence) 3) New research indicates that the brain region may prefer_________ notation to other numeric representations .( symbolic) 4) To do this, an ideal model based on the _________ paradigm was constructed and then compared with a neutral model reflecting the further education system as it existed before the Act took effect.( equality) 5) Is this not in flagrant _________to Einstein's rule that signals do not travel faster than the velocity of light?( contradiction) 6) Sequential organization has the major advantage that the records are stored in a _________ order, presumably that sequence to which the records are normally required for printing and for soft copy reports.( logical) 7) The mathematical _________ of a zero-sum two-person game is not difficult to construct, and determining the optimal strategies and the value of the game is computationally straightforward.( description) 8) The proof we now know required the_________ unknown in Fermat's time.( development) of an entire field of mathematics that was9) Williams adds that many courses in geometry, “the one high school class that demands _________ reasoning,” have already been “gutted” and are no longer proof-based.( formal) 10) The concept of total aircraft ownership will become increasingly important should the traditional trade structure be _________to cover the expanse of technologies economically.( unable) 2. Directions: Complete the sentences with the words given in the brackets. Change the form if necessary. 1) The key to unraveling such apparent paradoxes is to characterize the initial set of possibilities ("initial" meaning before you receive any extra information) and then to eliminate possibilities based on that extra information. (base) 42) Indeed, this separation of meaning is reflected by the definition of "weak" in the OALD, with a distinct sense reserved for its use when pertaining to that of solutions (definition) 3) The resulting radical pollution control programme outlined by Nixon, calling for a 90 per cent reduction in vehicle emissions by 1980, not only led to him being credited (albeit briefly) as policy initiator of an environmental clean-up but also provided him with the chance to deal a blow to one of his most important opponents in the 1972 elections, Edmund Muskie (blow) 4) Singapore's continuing investments in education and training has brought a tenfold increase in our pool of Information Technology professionals and the Singapore worker has been consistently rated by BERI as the world's best in terms of technical skills, attitude and productivity. (term) 5) In this work he was led to topology, a still new kind of mathematics related to geometry, and to the study of shapes (compact manifolds) of all dimensions. (lead) 6) If there is no allowable string which spans the whole graph, then we can search in the same way as described above, but wherever the required path does not exist in the tree, check if that position in the tree is flagged for end-of-word (way) 7) During the past century, steps forward in physics have often come in the form of newly found particles; in engineering, more complex devices; in astronomy, farther planets and stars; in biology, rarer genes; and in chemistry, more useful materials and medications. (form) 8) A second reason for measurements is the more theoretical, put by Love as " the discovery of numerical relations between the quantities that can be measured to serve as a basis for the inductive determination of the form of the intrinsic energy function. " (serve) 9) Thus the optimum conditions for coastal terrace development would seem to be areas with small tidal ranges. Finally, tidal range is an important factor in the generation of tidal currents which may locally become of geomorphological importance (become) 10) The original double entrance doors to the booking hall had been replaced by an utterly incongruous picture window as had adjacent booking hall and waiting room windows. (replace) 3. Directions: Reorder the disordered parts of a sentence to make a complete sentence. 1) A simpleway to describe topology is as a 'rubber sheet geometry' — topologists study those properties of shapes that remain the same when the shapes are stretched or compressed. 2) Since the mid-1990s scientists have floated the idea that representations of numeric quantities, whether expressed as digits or as written words, are codified by the parietal cortex, a higher-processing region in the brain located just above the forehead. 3) As activity was monitored, located just above the forehead ,researchers noted changes under the assumption that the brain reduces activity as it becomes accustomed to a stimulus and then reactivates when a novel stimulus is presented. 4) That has not stopped physicists from devising new algorithms for the devices, which can calculate a lot faster than ordinary computers—in fact, exponentially faster, in quite a literal5sense. 5) Such a device would be made of metamaterial, a thicket of metal rings or other shapes that bends light in funny ways. 4. Directions: Change the following sentences into nominalized ones. 1) The passage of night could be marked by the appearance of 18 of these stars. 2) The full proof of Fermat's Last Theorem is contained in these two papers. 3) The concept of fixed-length hours, however, did not originate until the Hellenistic period. 4) There is a probability that my first sock is red because only one of the remaining three socks is red. 5) The importance of accurate data in quantitative modeling is central to using Bayes's theorem to calculate the probability of the existence of God.Discourse Understanding1. C. A "3 percent margin of error" means that there is a 95 percent chance that the survey result will be within 3 percent of the population value.2. E. How is it that a survey of only 1,000 people can reach this level of accuracy?3. G. The margin of error depends inversely on the square root of the sample size.4. A. The margin of error is a mathematical abstraction, and there are a number of reasons why actual errors in surveys are larger.5. F. Finally, the 3 percent margin of error is an understatement because opinions change.Reading 2 (/doc/a90df7ed551810a6f524860e.html/article.cfm?id=mandelbrot-set-1990-hor gan) Section A Pre-reading TaskWarm-up Questions /doc/a90df7ed551810a6f524860e.html/article.cfm?id=mandelbrot-set-1990 1. Who discovered the Mandelbrot set? This is not a trick question, not easy to answer. Many people including Mandelbrot have laid claim to the discovery. 2. Why was the set named after Benoit B. Mandelbrot? The set is named after Benoit B. Mandelbrot, a mathematician at the IBM Thomas J. Watson Research Center because he coined the term fractal to describe phenomena (such as coastlines, snowflakes, mountains and trees) whose patterns repeat themselves at smaller and smaller scales. 3. Why has there been so much controversy about who discovered the Mandelbrot set?6Mandelbrot claims that he and he alone discovered the Mandelbrot set, but there are other mathematicians who have challenged his claim. 4. What did the challengers say about Mandelbrot’s claim of discovery? Two mathematicians said that they independently discovered and described the set at about the same time as Mandelbrot did. And another mathematician also asserted that his work on the set not only predated Mandelbrot's efforts but also helped to guide them 5. Why did some professors support Mandelbrot’s claim? Mandelbrot deserves to have the set named after him, because his efforts brought the set to the attention of both the public and of the pure-mathematics community.Section C Post-reading TaskReading and Understanding1. Choose the best summary of the passage. C A B D2. Complete the sentences based on the text. 1) The term Mandelbrot set is used to refer both to a general class of_________________ and to a particular instance of such a set. (fractal sets) 2) 2.In general, a Mandelbrot set marks the set of points in the _________________ such that the corresponding Julia set is connected and not computable. (complex plane) 3) "The" Mandelbrot set is the set obtained from the _________________ z_(n+1)==z_n︿2+c with z_0==c, where points in the complex plane for which the orbit of z_n tend to infinity are in the set. (quadratic recurrence equation) does not4) Setting z_0 equal to any point in the set that is not a _________________ gives the same result. (periodic point) 5) The Mandelbrot set was originally called a _________________ by Mandelbrot. J. Hubbard and A. Douady proved that the Mandelbrot set is connected( molecule) /doc/a90df7ed551810a6f524860e.html/11901033_d.html Language in Use1. Match the Chinese in the left column with the English in the right column. 迭代函数 iterative function 优先权之争 priority battle 分形特征 fractal properties7有意义 make sense 以越来越⼩的规模重复同⼀模式 patterns repeat themselves at smaller and smaller scales 混沌理论chaos theory 季刊 a quarterly journal 数学界 the mathematics community 波纹线 crisp lines 会议公报 proceedings of a conference 2. Join the following short sentences into longer ones. e.g. a. A fractal is generally a rough or fragmented geometric shape . b. The shape can be subdivided in parts. c. each part is (at least approximately) a reduced-size copy of the whole, a property called d. each part has a property of self-similarity. e.g. A fractal is generally "a rough or fragmentedgeometric shape that can be subdivided in parts, each of which is (at least approximately) a reduced-size copy of the whole", a property called self-similarity. 1) In addition to coining the term "fractal" to describe objects and surfaces which are irregular at various dimensions of scale, he also introduced such concepts as "fractal dimensions" and the particular fractal known as the Mandelbrot set, frequently represented with the mathematical formula z → z2 + c. 2) It appeared that things were settling into a pleasant and fruitful routine, with his school lessons supplemented by long talks with his uncle about classical analysis, the iterative work of Pierre Fatou and the equally fascinating Julia Sets generated by Gaston Julia 3) Just as the youthful Mandelbrot had passed his college entrance exams by translating algebraic problems into geometrical problems, and solving them by intuitively deducing the "perfected" shape, he here realized there was something deeper, something mathematical, behind these strange patterns. 4) But the beauty in Mandelbrot's models was not that they generated a deceitful randomness, but that they could generate graphed data whose visual pattern accurately mimicked the visual patterns created by real phenomena。
科技英语课后答案Exercise1Exercises 1II 翻译句子,注意“use”的词类与译法2.Use(名词) is made of electricity to run machines.=== Use of electricity is made to run machines.电(的功用)被用于驱动机械。
4.Computer have found wide use(名词)in industry.计算机在产业中找到了广泛的用途。
6.Electricity has been widely used (动词) in the modern world.电已被广泛应用于现代社会。
II 辨别句中的“to”是介词还是动词不定式的标志,并将句子译成汉语。
2.They often go to( 介词) the factory to(不定式标记)work with workers.他们经常到该厂与工人们一起劳动。
4. A magnetic field(主) is (系动词)able(形容词作表语)to (不定式标记)exert a force on an electric current.(不定式短语作状语,修饰表语)磁场能对电流施加作用力;6.The longer the wire, the greater the resistance to(介词)the electrons.线路越长,则对电子的阻碍越大。
由两个形容词比较级单句构成的主从复合句,均为倒装的主系表结构。
由原句省略is而来。
The longer is the wire, the greater is the resistance to the electrons.IV辨别句中的“it”是代词还是代替动词不定式的形式主语,并将句子译成汉语。
2. In order to improve the quality of the product, it(形式主语)is necessary to make various experiments.为了提高产品质量,进行各种实验是必要的。
第一部分《计算机英语》参考译文第一单元:计算机与计算机科学课文A:计算机概览一、引言计算机是一种电子设备,它能接收一套指令或一个程序,然后通过对数字数据进行运算或对其他形式的信息进行处理来执行该程序。
要不是由于计算机的发展,现代的高科技世界是不可能产生的。
不同类型和大小的计算机在整个社会被用于存储和处理各种数据,从保密政府文件、银行交易到私人家庭账目。
计算机通过自动化技术开辟了制造业的新纪元,而且它们也增强了现代通信系统的性能。
在几乎每一个研究和应用技术领域,从构建宇宙模型到产生明天的气象报告,计算机都是必要的工具,并且它们的应用本身就开辟了人们推测的新领域。
数据库服务和计算机网络使各种各样的信息源可供使用。
同样的先进技术也使侵犯个人隐私和商业秘密成为可能。
计算机犯罪已经成为作为现代技术代价组成部分的许多风险之一。
二、历史第一台加法机是法国科学家、数学家和哲学家布莱斯?帕斯卡于1642年设计的,它是数字计算机的先驱。
这个装置使用了一系列带有10个齿的轮子,每个齿代表从0到9的一个数字。
轮子互相连接,从而通过按照正确的齿数向前转动轮子,就可以将数字彼此相加。
17世纪70年代,德国哲学家和数学家戈特弗里德?威廉?莱布尼兹对这台机器进行了改良,设计了一台也能做乘法的机器。
法国发明家约瑟夫―玛丽?雅卡尔,在设计自动织机时,使用了穿孔的薄木板来控制复杂图案的编织。
在19世纪80年代期间,美国统计学家赫尔曼?何勒里斯,想出了使用类似雅卡尔的木板那样的穿孔卡片来处理数据的主意。
通过使用一种将穿孔卡片从电触点上移过的系统,他得以为1890年的美国人口普查汇编统计信息。
1、分析机也是在19世纪,英国数学家和发明家查尔斯?巴比奇,提出了现代数字计算机的原理。
他构想出旨在处理复杂数学题的若干机器,如差分机。
许多历史学家认为,巴比奇及其合伙人,数学家奥古斯塔?埃达?拜伦,是现代数字计算机的真正先驱。
巴比奇的设计之一,分析机,具有现代计算机的许多特征。
第一单元自动化第二部分阅读A自动化的含义“自动化”已经是,而且现在仍然是,一个被大量滥用的词。
但是,人们对其确切的意义以及所包括的内容,正在逐渐地有了较为正确的了解。
如果不是下一个定义的话,我也许可以尝试作些解释,把自动化说成是一个概念。
运用这个概念,人们通过对机器装置的性能进行充分的测量、观察和控制,从而使其以最高的效率运转。
这需要对这种装置的功能有一个详细而连贯性的了解,以便需要时便能运用最佳的矫正操作。
自动化按其确切的意义,只有全面运用通信、计算和控制三个主要组成部分(“三C" )才能完全实现。
我认为,确保人们对合为一体的三个组成部分对我们的社会所蕴含着的某些意义有所认识和了解,是很有必要的。
首先,我们不妨考虑工业部门之一的炼钢工业。
在炼钢工业中,自动化已经开始成型。
到过钢厂的人都会知道从高炉开始的各种工艺流程的一些情况,成品条钢或板钢生产出来之后,再准备送往制造工艺车间或汽车厂,这些工艺流程是相互链接的。
为了使工厂中各个车间充分发挥效率,可以使用计算机来控制每个车间。
在此之前,计算机工作所需要的一切资料均输入机内。
就高炉来说,需要给计算机提供装人高炉的原料的信息、高炉工作温度的信息和处理各种各样配料的最好方法等方面的资料。
钢厂的高炉操作是一项复杂而要求技术熟练的作业,需要大量的知识和大量的综合信息,并迅速地做出判定选择,以便确保高炉工艺流程中的下一阶段的有效工作。
计算机对所有这一切都了解得很透彻,能够做出非常大量的中间判定,并且能够把全部信息立刻和不间断地提供给管理人员,以使他们做出高效管理这个工厂所需要的最后决定。
由此产生的信息数据和判定要进行处理,然后转送到下一个工序。
在这里,对操作的一些专门细节再次进行整理,提出最佳和最终的判定,然后对这些信息再一次进行处理并输送给下一道工序。
同时,当信息数据从生产单元的一道工序输送到下一工序并完全结合成为一项新的操作时,每次变化的结果反馈到最初阶段,而且,不断地做进一步的调整,结果是整个工厂的工艺流程便能够高效率地进行下去。
Unit 2近年来,西方国家的传统工业日趋萎缩,而以新兴技术为基础的工业蓬勃发展。
人们普遍认为,目前世界正在经历着一场新的技术革命,而新技术革命的物质基础是新兴技术群。
In recent years, traditional industries in Western countries increasingly shrinking, and the emerging technology-based industries to flourish. People generally believe that the world is experiencing a new technological revolution, and the material basis of the new technological revolution is the emerging technology group.而新技术革命的物质基础是新技术群。
The material basis of the new technological revolution is a new technology group它是以电子技术、生物工程、空间技术、海洋开发、光纤通讯、材料技术等等到为主导技术,所构成的新兴技术体系t is based on electronic technology, biological engineering, space technology, ocean development, optical fiber communications, materials technology, and to the leading technology, which constitute the system of emerging technologies新兴技术群体以微电子技术为中心,构成了深刻影响社会产业和经济结构的技术因素。
科技英语课后练习答案Unit 1 练习答案及课文译文Part 2 Reading AI1 F2 T3F 4T5T 6.F 7.T 8.T 9.F 10.TII1. Reducing the time and cost of product development and production.2. The product cycle is composed of two main processes:the design process and the manufacturing process.3. The activities involved in the design process can be classified largely as two types:synthesis and analysis.4. Rapid prototyping is becoming popular because this technology enables the construction of a prototype by deposition layers from the bottom to the top.5. This includes the preparation of drawings,reports,and bills of materials.III1.d2.e3.b4.j5.i6.c7.f8.h9.g 10.aIV1.处理速度2.用户友好的交互图形3. 产品周期4. 设计规格5. 设计评价6.CAD7.CAM8.CAE9.design process 10.production processUnit 3Part 2 Reading AⅠ Mark the following statements with T(true ) or F (false) according to the passage.1.F2.T3.F4.F5.T6.F7.T8.T9.F 10.FⅡGive brief answers to the following questio ns.1. Nissan will unveil a new city car ,the pixo and a battery-electric concept car2. Pixo is available with manual or automatic transmissions.3. Sales start from late spring 2009.4. The NuVu battery pack uses new laminated lithium-ion cells with a capacity of 140 wh/kg .5.There are no door mirrors to disturb the airflow.Ⅲ Match the items listed in the following two columns.1-5 j f d c g6-10 e I h b aⅣ Translate the following expressions.1.手动或自动挡2.内部设计3.薄板锂离子电池4.太阳能电池板5.头尾灯6 concept car7. Horse power8. test bed9. battery pack10. turning circleⅤTranslate the following sentences into Chinese.1. 尼桑推出了一种新产品—城市汽车Pixo和一款电力驱动的概念车—NuVu,预示了尼桑未来的重点会放在电力驱动车上。
1.把激光射束射向地球Laser beams are emitted at the moon2.这个模型描述了原子的情况This model is descriptive of the behavior of an atom3.那位教授将做有关移动通讯方面的讲座That professor will deliver a lecture on mobile communication4.她给本科生上C++程序设计语言课She gives undergraduates lessons in the C++programming language5.这些学生在做物理实验These students are making an experiment in physics6.他们在做电学实验They are doing an experiment on electricity7.该教授对沃氏函数的研究起了重要作用The professor has played an important role in the research on the Walsh Functions8.无线电波朝四面八方传播Radio waves travel in all directions9.为此,我们必须在负载两端接一个电容器For this purpose,we must connect a capacitor across the load10.在这个温度上该金属就会融化At this temperature the metai will melt11.该专家将在会议上宣读一篇重要的学术论文The expert will read an important academic paper at the conference12.速度等于距离与时间之比Speed is the ratio of distance to time13.太阳离地球的距离是很远的The distance of the sun from the earth is very great14.温度对金属导电率的影响是很小的The effect of temperature on conductivity of metals is small15.本节论述晶体管与电子管相比的优点This section deals with the advantages of transistors over electron tubes16.重力加速度随纬度的变化,部分原因是由于地球的自转The variation of g with latitude is due in part to the earth’s rotation17.Y对x的依从关系用y=f(x)表示The dependence of y on x is expressed by y=f(x)18.人们用椭圆来描述行星绕太阳的运行情况Ellipses are used to describe the motions of the planets around the sun19.我们讨论了电流通过酸碱盐溶液的情况We have discussed the passage of an electric current through liquid solutions of acids,bases,and salts20.物体对净力F的影响就是正比于F的加速度a The response of a body to a net force F is an acceleration a proportional to F21.把式(4)与式(6)相比较,我们就能的得到一下几个关系式A comparison of Eq.(4)with Eq.(6)Leads to the following relations22.我们可以把一个力分解成x和y分量The resolution force into x and y components is possible23.应避免使人体接触有潜在毒性的物质Exposure of the body to potentially toxic substances should be avoided24.这些特殊问题是有把原子能用作为能源而产生的These special problems arise from the use of atomic energy as a source of power25.把电流定义为电荷的运动对我们大家都是熟悉的The definition of an electric current as the flow of electric charge is familiar to all of us26.哥伦布发现美洲是在哪一天What is the date of the discovery of America by Columbus27.爱因斯坦确立了相对论是20世纪最重要的事件之一The formation of the theory of relativity by Einstein is one of the most significant events of the 20th century 28.门捷列夫于1869年发现了周期表使人们有了计算原子质量的另一种方法The discovery of the periodic table by Mendeleev in 1869 suggested another way of estimating atomic masses29.这个工厂和那个一样大The factory is as large as that one30.铜的导电能力几乎和银一样好Copper conducts electricity almost as well as silver31.这台计算机的体积是一台打印机的3倍The size of this computer is there times as large as that of a typewriter32.那根导线长达100米That wire is as long as 100meters33.这根导线不如那根长This wire is not as long as that one(is)34.这台计算机的性能不如那台好This computer dose not work so well as that one35.导线越长,电阻越大The longer the wire ,the greater the resistance36.电压越大,电流就越大The greater the voltage,the larger the current37.电流越大,在导线中产生的热量就越多The larger the current,the more heat will be produced in the wire38.你学习越努力,你的进步就会越大The harder you study ,the greater progress you will make39.在无线电接收机中,一部分功率转变成了声波In a radio receiver,some power is converted to song waves40.绝缘体可以被用在导体之间来防止电流在他们之间流动Insulators may be used between conductors in order to prevent the flow of electric current between them41.把理论应用于实践是非常重要的To apply theory to practice is very important42.制作这样的电感器需要许多这样的线匝和铁芯To construct such inductors requires many turns of wire and iron cores43.现在能够把太阳光直接转变成电It is now possible to convert sunlight directly into electricity44.我们似乎能求出这个电流It seems possible to find out this current45.操作这台机器并不是件容易的事It is not an easy job to operate this machine46.做实验是极为重要的It is of great importance to make experiments47.解这个方程将要花费我们许多时间It will take us a lot of time to solve this equation48.我们发现用弧度而不是用度数表示角度是比较方便的It is found convenient to express angles in radians rather than in degrees49.当电流流过电路时,要损耗掉一部分能量Flowing through a circuit,the current will lose part of its energy50.若已知电流和电阻,我们就能求出电压Given current and resistance,we can find out voltage51.由于铜具有大量的自由电子,所以它是良导体Having a large number of free electrons,copper is a good conductor52.若用公式表示的话,电路中的电压,电流,电阻之间的关系可写成V=IR Expressed in a formula,the relationship between voltage,current and resistance in a circuit can be written as V=IR53.由于铜是电的良导体,所以被广泛的用在电工技术中Being a good conductor of electricity,copper is widely used in electrical engineering54.银是最好的导体,其次是铜Silver is the best conductor,followed by copper55.Σ是希腊字母“西格玛”,它的意思是“...之和”Σis the Greek letter sigma,meaning“the sum of”56.当机车拉着火车跑时,它就会做功A locomotive does work while pulling a moving train57.将物体置于水中,就会感觉到他比较轻When placed in water,everything will be found lighter58.这一设备,如果设计得当就可以用无线电控制This device,properly designed,can be controlled by radio59.当把雷达信号发向月球时,由于月球是固体,所以能反射信号When radar signals are sent to the moon,the moon,being solid,reflects them60.若该电流发生变化,磁场也将变化This current changing,the magnetic field will change as well61.若其他情况相同,电阻将正比于导体的长度Other things being equal,the resistance is directly proportional to the length of the conductor62.当阳光照在光电电池上时,该设备就会自动工作起来The sunlight falling upon photo-electric cells,the device will automatically go into operation63.由于原子很小,所以我们看不见它们Atoms being extremely small,we cannot see them64.几乎所有的金属都是良导体,而银为最好Almost all metals are good conductors,silver being the best65.每当导体内的电流发生变化时就会在到体内感应出一个电动势,因而这种电动势就成为自感电动势Whenever there is a change of current in a conductor,an emf is induced in the conductor,thus this kind of emf being called a self-induced emf 66.银在金属中电阻率最低,而铜的电阻率比他高不了很多Silver has the smallest resistivity of any metal,with that of copper not much greater67.若电路中没有电阻,电流就会无限增大With no resistance in the circuit,the current would increase forever68.我们周围的一切东西均是物质这一事实是大家都知道的The fact that everything around us is matter is known to all P(127)69.在这种情况下,该函数必须存在这一条件并没有满足In this case ,the condition that the function must exist is not satisfied70.等式只是某个量等于另一个量的一种陈述An equation is simply a statement that a certain quantity ia equal to another one71.欧姆观察到这一事实:如果电压保持不变,则电阻越大,电流就越小Ohm observed the fact that if the voltage remains the same,the greater the resistance,the smaller the current72.质子和电子之间所观察到的作用力,就导致了大家所熟悉的说法;同种电荷相互排斥,一中电荷相互吸引The observed forces between protons and electrons then lead to the familiar statement that like charges repel one another,unlike charges attract one another73.这些实验用来证实吉尔伯特的结论:电荷有两种There experiments serve to confirm Gilbert's conclusion that there are two kinds of electric charge74.电子学的诞生,是从发现了真空二极管中的电流,可以通过引入第三个电极来加以控制这个时候算起的The advent of electronics is reckoned from the discovery that the current in a vacuum diode can be controlled by introducing a third electrode75.十九世纪科学上最显著的成就之一是人们认识到了光是由电磁波构成的Among the most noteworthy achievements of 19th century science was the realization that light consist of electromagnetic waves76.现在人们越来越认识到这些技术在诸如控制系统和仪表测量这样的领域中也是很有价值的There is a growing awareness that these techniques are also of value in such areas as system control and instrumentation77.这两个带电球之间的斥力表明具有同种电荷的物体相互排斥The repulsion between these two charged balls is evidence that bodies having like charges repel each other78.由图2可以看出这一现象与反射有关That this phenomenon has connection with reflection may be seen from Fig.2 P(137)79.每个电路的工作原理在这一章进行了详细的讨论How each circuit works is discussed in detail in this chapter80.我们用哪个式子,将取决于在题目中给出了那些数据Which equation we want to use will depend on what data we have been given in a problem81.我们可以用计算机解决这些复杂的题目It is possible that we use a computer to solve these complicated problems82.有趣的是,每个函数均可用一些简单函数来近似It is interesting that every function can be approximated by simply functions83.那个问题是如何解决的还是个谜It is a mystery how the problem was solved84.众所周知我们周围的一切东西均为物质It is known that everything around us is matter85.在很久以前人们就发现电流的方向与电子的方向相反It was found long ago that the direction of the current is just opposite to that of the electron flow86.我们已经知道接收到的信号一般是很微弱的,其通常的功率约为几皮瓦It has been known that the signal received is generally quite weak,powers of the order of picowatts being common87.尚不了解有那些因素决定这种灯丝的尺寸It is not yet understood which factors determine the size of filaments of this kind88.我们无法预言这种现象何时发生It cannot be predicted when this phenomenon will take place89.朝哪个方向运用NPN晶体管基本上是没什么区别的It does not basically make any difference in which direction an NPN transistor is operated90.我们知道磁场能对电流施加一个力We have known that a magnetic field is able to exert a force on an electric current91.我们可以说物体的能量就是物体做功的能力One may say that the energy of a body is the ability of that body to do work92.我们往往想要知道这一误差是否可以忽略不计We often want to know whether this error may be neglected93.事实是无线电波的传播速度和光速一样The fact is that radio waves travel as fast as light dose94.其结果将是在导线两端之间将会存在这种电位差The result will be that this potential difference will exist between the ends of the conductor95.温度是与物体的体积无关的一种物质性质Temperature is a property of the body not concerned with how large the body is96.上面所讲的就是欧姆定律What has been described is Ohm's law97.我们能够学会我们原来不懂的东西We can learn what we did not know98.计算机能够做人们告诉它要做的事A computer can do what it has been told to do99.发电机的功能是把机械能转换成电能What a generator dose is convert mechanical energy into electrical energy100.作用在载流导线上的磁力就是使电机工作的力The magnetic force on current-carrying wires is what makes electric motors work101.我们想要获得对于A、B两点之间所发生的情况的详细描述We wish a detailed picture of what happens between points A and B102.所得到的是同样的那些表达式What result are the same expressions103.这个能量就是给自感电动势供能的能量This energy is what powers the self-induced emf104.众所周知(的是)光是一种电磁波What is well know is that light is a kind of electromagnetic wave105.这就是我们通常所说的力This is what we call a force106.电子计算机能懂得所谓的机器语言The electronic computer is able to understand what is known as the machine language107.电流随所谓的电阻变化Current changes with what is described as resistance 108.反射回来的那部分电流形成了所谓的回波信号The reflected portion of waves forms what is referred to as the echo signal109.存在有许多自由电子的物质被称为导体The substance in which there are many free electrons is called a conductor110.电流流过的闭合通道被称为电路The close path though which current flows is referred to as the electric circuit111.电动机是把电能转换成机械能的一种机器An electric motor is a machine by which electric energy is chang into mechanical energy112.存储电荷的器件称为电容器The devices on which charges are stored are called capacitors113.光传播的速度是极快的The spend at which light travels is extremely great 114.用来把热能转换成功的任何机械装置均称为热机Any mechanical device by means of which heat is converted into work is called a heat engine115.惯性是物质的一种特性,由于这种特性,要使物体加速就必须对该物体施加一个力Inertia is that property because of which a force must be exerted on a body in order to accelerate it116.正如标题所示本章论述数字计算机的原理As the title indicates,this chapter deals with the principles of digital computers117.我们知道,电子是微小的负电荷Electrons,as one knows,are minute negative charges of electricity118.我们已讲过晶体管是电流控制器件As has been described,transistors are current-control devices119.晶体管体积小效率高这是大家所熟知的Transistors are small & efficient,as is well known to us120.顾名思义流体是一种容易流动的物质Fluid,as the name shows,is a substance that flows readily121.一根导线可用作为天线A wire can serve as an antenna122.作为通讯工具,卫星是最先进的As a means of communication,a satellite is the most advanced123.能量被定义为物体做功的能力Energy is defined as the ability of a body to do work124.我们把g这个量定义为重力加速度We refer to the quantity g as gravity125.一个常数无论有多大,均不可能称为无穷大A constant number,no matter how large it may be,is never spoken of as infinite126.把能量定义为物体做功的能力是合理的The definition of energy as the ability of a body to do work is reasonable127.当电流流动时电池的能量就给电阻消耗了As the current flows,energy from the battery goes to the resistance128.两物体间的万有引力,随他们之间的距离的增加而减弱The force of gravitational attraction between two bodies decreases as the distance between them increases129.由于空气有重量所以它对处于其中的任何物体均要施加一个力As air has weight,it exerts force on any object immersed in it130.电子绕原子核旋转,就像行星绕太阳运行一样Electrons move round the nucleus just as the planets moves round the sun131.这台计算机与那台一样重This computer is as heavy as that one(is)132.原子虽小,却是由一些更小的单元组成Small as they are,atoms are made up of still smaller units133.正如早已证明的那样,若使负的各项变为正,该级数就发散If the negative terms are made positive the series becomes divergent,as has been shown already 134.我们必须记住用以表示化学元素的那些符号We must remember such symbols as are used to represent chemical elements135.我们也可以用计算机解这道题A computer can be used as well to solve this problem136.我们能求出流过这个电阻的电流及两端的电压It is possible to find out the current through this resistor as well as the voltage across it137. 这台计算机的工作性能与那台一样好This computer works as well as that one dose138.数学是一种非常有用的工具,因此它广泛用在工程的各个领域之中Mathematics is a very useful tool.As a result,it is widely used in various fields of engineering139.只要外加电压保持不变在电路中流动的电流与该电路中的电阻成反比The current flowing in a circuit is inversely proportional to the resistance in the circuit as long as the applied voltage remains constant140.若地面没有摩擦,就不可能停止任何物体的运动Were there no friction on the ground,it would be impossible to stop the motion of any body141..若电压不那么高的话,那台仪器也就不会被烧坏了That instrument would not have been damaged had the voltage not been so high142.如果在导线中有很强的电流,那么只要用一匝大号导线就可以制成磁性很强的电磁铁A powerful electromagnet can be made with only one turn of a large-sized wire,should a very large current flow in the wire143.若没有地球的引力,地球上的一切东西都要失重Everything on the earth will lose its weight provided there be no gravity144.若没有半导体,就不可能有卫星通讯这类事情Some things,like satellite communications,would be impossible without semiconductors145.要不是二进制,电子计算机可能要比现在复杂得多But for the binary system,the electronic computer might have been much more complicated146.我们本来可以用定理(6)来导出式(5)We could also have used Theorem(6)to derive equation(5)147.为了使电流在电路中流动,必须保持一个电位差It is necessary that potential difference be maintained for current to flow in a circuit148.数字电路设计人员必须很熟悉布尔代数的实用知识It is essential that the digital designers should have a good working knowledge of Boolean algebra149.我们希望机器都不要有能量消耗It is desired that any machine have no energy loss150.有人建议在太空制造药物It is suggested that drugs be made in space151.我们建议读者最好用袖珍计算器来做基础电子学中的所需的数学计算It is recommended that the reader use a pocket calculator to do mathematical work required in basic electronics152.经济方面要求电力以高压传送Economy demands that electric power be transmitted at high voltage153.实验要求测量应精确Experiments require that accurate measurements be made 154.我们建议把这一点接地Our suggestion is that this point be grounded155.这是由于输出必须稳定的原因This comes from the necessary that the output be stable156.这根传输线的作用就好像它是开路似的This transmission line acts as though it were open-circuit157.在这种情况下金质叶片就会散离开来,就好像它们由通过接触而起电的物体而带电一样Under this condition the gold leaves will diverge just as if they had been charged from a body electrified by contact158.电位差使电流在电路中流动The potential different causes an electric current to flow in the circuit159.正是电位差使得电流在电路中流动It is the potential difference that causes as electric current to flow in the circuit160.物体的惯性质量与重力质量是成正比的,这是一个极为重要的实验事实It is very significant empirical fact that the inertial and gravitational masses of a body are proportional to each other161.是硬件在很大程度上确定了该系统的能力It is the hardware which determines to a large degree the capabilities of the system162.正是这些优点使阿拉伯数字为全世界人们所接受It is these strong points that make the Arabic figures accepted by people all over the world163.直到1925年才证实了电离层的存在It was not until 1925 that the existence of the ionosphere was proved164.是法拉第首先发现了电磁感应现象It was Faraday who first discovered electromagnetic induction165.正是这些力导致产生了磁现象It is these forces which lead to magnetic phenomena166.天平所度量的实际上是质量不是重量It is actually mass not weight which the balance measures167.正是在那儿发射了第一颗卫星It was there that the first satellite was launched 168.正是在这个意义上数学有时被称为科学的语言It is in this sense that mathematics is sometimes called the language of science169.正是当导线切割磁力线时在导体上感应出一个电动势来It is when lines of force are being cut by the wire that an emf is induced in it170.并不是科学家使用的工具而是他使用工具的方法使他成为科学家It is not the tool a scientist uses but how he uses these tools that makes him a scientist171.没人知道到底是什么东西构成了场本身No one knows what it is that composes the field itself172.大多数数字电路是与其它数字电路对接的。