西安电子科技大学研究生【专业英语】(科技英语)教材参考答案
V、练习参考答案
练习1
I、
1、the（各项均为负。)
2、the; a （功率额定值是电阻器不会引起温度太大的上升而能安全地耗散的最大功率。）
3、an（这是均方根值伏特计。）
4、The; a（该设备的成功设计需要详细地了解性能指标。）
5、the; a; a（在氢原子的布尔模型中，一个电子绕一个质子以半径为R的圆周运转。）
6、the（电阻的单位是欧姆。）
7、an （这是一个h参数。）
8、/; /（图5－1画出了Oersted的实验。）
9、A; a; a（机器是能够传递力来完成某一确定目的的一种设备。）
10、/（水压机将在第14章加以考虑。）
11、the; the [/]（我们容易确定参数μ的值。）
12、/; the（根据式（2－1），我们得到以下的关系式。）
13、the; /（作者工作在位于阿林顿的得克萨斯大学。）
14、an（甚至当积分区间并不是无穷时，能够恰当地显示一个时函数的傅氏变换的仪器是多么重要啊！）
II、
1.Dr. Emmet graduated from Harvard University in 2001.
2.Professor Li earned his Ph.D. degree in mechanical engineering Xi’an University of
Technology in 1988.
3.Now we shall turn to the discussion of local area networks.
4.
5.或
is its mass per unit volume.
6.An increase in pressure always causes a decrease in volume.
7.Fig. (2-5) shows what is expressed by Eq. (2-2).
8.
III、
1.
2.Finally, a broad stepped impedance transformer is designed by this method.
3.
4.
5.
练习2
1. This circuit consists of a battery, an inductor and a capacitor.
2. Compute the electric fields at points a, b, and c.
3. This satellite is used for communications between the United States and Great Britain, France and Italy.
5. Chapters 6, 7, and 8 deal with transmission lines.
II、
1. Its error is six parts in 101
2.
2. This computer stores four times more information than that one (does).
3. The demand for this kind of equipment in the near future will be 20 times what it is.
4. The voltage across this component is a few tenths of a volt.
5. Now its internal pressure is one third what it was.
III、
2. Unless otherwise stated, it is assumed that silicon transistors are used I CBO can be neglected.
4. Figs. 1, 2, and 3 show this process in detail.
练习3
I、
1. This new type of computer has many advantages over the general type.
2. It is not difficult to solve this differential equation for the unknown quantity.
3. Of these five new chapters, the first one deals with the basic principles of negative feedback.
4. At this point/time, current differs in phase from voltage by 90o.
5. By analyzing [By the analysis of] the parameters of the instrument, we can understand its performance.
6. We will find out its average velocity over this distance.
7. The science of electronics is too important in the world today.
8. They solved this problem with great difficulty.
II、
1. For x＞1, there is no solution to this equation [this equation has no solution].
2. Upon [On] substituting [substitution of] these values into [in] the
equation, we obtained the following expression..
3. This circuit is similar in operation to that of Fig. 1-10.
4. This computer is very good in performance.
5. These waves travel only in one direction.
th of October.
4. V
6. Unless otherwise stated, it is assumed that silicon transistors are used I CBO can be neglected.
7.
练习4
I、
1. The force acts perpendicular to the surface of the table.
2. The three coefficients here remains to be determined.
3. The two equations below will be often (frequently) used in later chapters/in the chapters which follow.
4. Here we use two metal balls 10 cm apart.
5. The output remains/stays constant/unchanged/fixed/unaltered/the same.
6. All the textbooks available discuss this problem.
7. Accurate in operation and high in speed, computers have found wide applications.
8. The answer to this problem looks correct.
9. Two parallel wires a distance (of)δapart carry the current i.
10. The problem now is how to measure the voltage across this component.
11. These data will be sent to the computing center 2 kilometers away.
12. Upon rearranging the equation above, we have [get, obtain] the following expression.
13. These charges can interact with other charges present.
14. Forces can be transmitted without contact, contrary to the common belief.
15. This coefficient is typically 0.35.
II、
1. In this case, the input does not fall; nor [neither] does the output. […; the output does not fall, either.]
but also on the size and temperature of the conductor.
练习5
I、
k has the same unit as work (does).
II、
electrical engineering.
III、
R o.
6. We must take the effect of temperature on [upon] semiconductors into
account.
7. In this case, the variation of output with input is very small.
8. This curve shows the dependence of distance on/upon speed.
IV、
练习6
I、
1. This image, it will be noticed, is a real image.
2. This technical problem, we hope, will be solved soon.
3. 210 is approximately 1000, a fact that we think is very useful in the study of digital electronics.
4. A resistor of say 100 ohms should be used here.
II、
radars.
III、
1. In Section 1-2, the concept of force was introduced.
2. As early as the 1940s, it was found that semiconductors are very useful.
3. This result can also be arrived at in another way.
4. At that time no use was made of this phenomenon/…, this
phenomenon was made no use of.
5. This point will be dealt with in the next section.
IV、
1. This computer works than that one (does)/This computer is much better in performance than that one (is)..
4. The greater the resistance, the longer time it takes for the capacitor to reach its maximum voltage/…, the longer time is required for the capacitor to reach its maximum voltage.)
5. The current as small as 0.1 A cannot produce enough heat.
V、
或：We can determine the weight of the body easily.
6. The results obtained values. […are in agreement with the experimental values.]
练习7
I、
1. It will take a few months to design this kind of aircraft with the help of a computer.
2. It is left as a problem to [for] the reader to show that this expression holds.
3. The program to be executed is stored in this unit.
4. This valley acts as the foundation on which to build the dam.
5. In this laboratory there are many kinds of instrument for students to choose from.
6. Let t0 equal/be equal to zero.
7. The farther away the target (is), the longer time it takes for the echo to return.
8. For the series to converge, x must be less than 1.
9. We find this concept very difficult to understand.
10. This method makes it much easier to detect targets.
11. This factor will affect the ability of a computer to store information.
12. We have to find out how large to make r so as for the series to converge.
13. This is a pen to draw pictures with.
14. Elasticity is the tendency of a body to return to its original condition after being deformed.
15. Ordinary matter is said to be electrically neutral.
16.This property makes it possible for metals to be made into any shape.
17. This table is unfit for a student to do experiments on.
18. Now we consider what path of integration to take.
II、
of impurities to
练习8
I、
1. The amplifier amplifies the received signals.
2. Moving molecules have kinetic energy.
3. Speed equals distance divided by time.
4. V oltage equals/is equal to current multiplied by resistance.
5. The resistance of air increases with the increased/increasing/an increase in speed.
8. This book, properly used, will be of great help to the reader.
9. Flowing through a circuit, the current will lose part of its energy.
10. Given/Knowing time and speed, we/one can find out distance.
11. Having studied this chapter, the student will understand/will have understood the principle of a computer.
12. The speed of light being extremely great, we cannot measure it by ordinary methods.
13. Several comsats were launched, all of them (being) high-altitude satellites.
14. Called “the mother of all networks,” the Internet is a widely used international network.
15. This force can be resolved into two components, one (being) horizontal and the other vertical.
II、
1.Let us construct/draw a circle with the origin as the center and of
radius R.
2.This parameter should be measured with E grounded.
3. With no resistance in the circuit, the current will increase indefinitely.
4. With this in view, we have written this book.
5. This paper introduces a new design method/technique, with emphasis on its principle.
III、
1.Let us consider designing a computer.
2.We refer to these components as being passive.
3.This involves taking the Fourier transform.
4.On/Upon rearranging the above equations, we obtain the following set
of equations.
5.In using this equation, it does not matter which plane is considered as
IV、
1.
2.
3.
4.
5.
练习9
I、
1. The problem was not solved until a completely different method was introduced.
2. Nearly 100 years passed before the existence/presence of subatomic particles was confirmed by experiment/experimentally.
3. The year this device was invented, World War II broke out.
4. Small as they are, atoms are made up of still smaller particles.
II、
1. The relation that voltage is the product of current and resistance applies to all the dc circuits.
2. The discovery that magnetism can produce current is extremely important in the field of electricity.
3. An equation is an algebraic statement that two algebraic expressions are equal.
4. There is evidence that no life exists on the moon.
5. The question now arises whether the algorithm is of practical use.
6. In this case there is no guarantee that the series is convergent.
7. There is a growing/increasing awareness that these techniques/methods are very useful.
8. One of/Among the most noteworthy achievements at that time was the realization that light consists of electromagnetic waves.
10. Besides/In addition that the properties of the material should be included in the analytical model, we must take other factors into account.
III、
1.These features make it difficult for electronic counter-measure systems
to intercept, analyze and jam this kind of signals.
2. The existence of and the ability to control these phenomena make those devices possible.
3. The variation of/in the number of the filter’s teeth has a greater effect on the performance of its passband than the variation of/in its dimensions.
4. Scalar detection will result in the loss of some phase information.
5. Fig. 6 shows the schematic diagram of measuring scatter parameters by the natural parameter transformation method.
练习10
I、
1. Now it remains to be determined when the series converges.
2. It is clear from Dubamel’s Theorem that this limit exists.
3. It follows from Maxwell’s hypothesis that whenever there is a change in an electric field, a magnetic field is produced.
4. It does not matter whether the magnet is moved in this case.
5. Temperature determines in what direction the transfer of heat will take place.
6. It is now a well-known fact that all matter consists of tiny particles.
II、
1. What a generator does is (to) change mechanical energy into electrical energy.
2. What this chapter describes/What is described in this chapter is of great importance.
3. Matter is what can occupy space.
6. Magnitude, direction, and place of application are what we call the three elements of a force.
7. These numbers constitute what is known as the real number system.
8. In what follows, we shall acquaint ourselves with some basic concepts.
III、
1. An x-band wave-guide test system is shown in Fig.7. [或：Fig. 7 shows …].
2. This method lowers the requirement for the hardware of a sample
network.
3. On the basis of the above analysis of the decomposition of the polynomial, a novel configuration results. [或：The above analysis of the decomposition of the polynomial results in a novel configuration.]
4. Finally, an analysis of packet loss probability is made by computer simulation.
5. The sparse ratio of the resulting impedance matrix is as high as 40%.
练习11
I、
1. The meter (that/which) we use to measure the voltage across a resistor is called a voltmeter.
2. Computers are the most efficient assistants (that) man has ever had.
3. Now this disease is no longer the serious problem (that) it once was.
4. Radar can measure the time (that) it takes for the radio echo to return.
5. We must calculate the distance (that/through which) the body is lifted.
6. The direction (that/in which) a body moves is also very important.
7. The number of times (that/by which) this particle vibrates per/a second is called/termed/named/known as/spoken of as/referred to as frequency.
8. We equate these two ratios, from which the simplest formula follows/results.
9. It is necessary to determine the time when/that/at which the y-component has decreased to zero.
10.. The curve the y-coordinate of each point on which is zero is just the x-axis.
II、
1. The point at which the circle cuts the axis of reals is where α= ω.
2. The force of gravity means the force with which the earth attracts a body.
3. The surface of a picture tube upon which the electrons produce the picture is called the screen.
4. The author would like to express thanks to the editors of the series of which this book is a part/to which this book belongs.
5. This is a parallelogram of which the two given vectors are/form sides.
6. The pressure is equal to the total force divided by the area over which it is exerted.
7. The two elements of which water consists are hydrogen and oxygen.
8. This depends on the efficiency with which electrons are produced.
III、
1. As the title indicates, this chapter will discuss nonlinear equations.
2. As the name shows, a fluid is a substance which flows readily.
3. This single force produces the same effect as is produced by those forces together.
4. Now we are able to solve such differential equations as occur in physics.
5. This function can be accomplished by using the full adder as was described in the previous section.
6. These concepts enable us to understand a wide range of phenomena in electrostatics, or “static electricity,” as it is called.
7. This current is, as predicted, very small,
8. First let us consider the simplest circuit as shown on page 2.
IV、
1. This is a slightly higher value than we predicted.
2. This reactor can produce more fuel than it consumes.
3. Let us consider the case when the torque is zero.
4. We must determine the values of currents and voltages after the switch closes.
5. During the ten years since this book was first published, significant changes have taken place/have been seen in metal-making.
V、
of voice service.
2. This paper presents a an 8098 microcontroller to series-communicate with a 386 personal computer.
analysis is made of the effect of equalization parameters on equalization performance.]
4. Each receiver channel in Fig. 1 contains an RF a an IF amplifier, an A/D
etc.”的黑点重合在一起了）
5. The larger the abnormal extent (is), the larger is the residual mismatch, with the curve going up.
练习12
I、
1. be grounded;
2. be carried;
3. be raised;
4. be;
5. not try;
6. be; be satisfied;
7. be;
8. be; was; have;
10. were concentrated; 11. had been; 12. were moving; 13. is going to rain; 14. be; 15. leak
II、
1. Should anything abnormal happen, switch/turn off the power supply at once/immediately.
2. Had electronic computers not been used, it would have taken them a long time to solve this problem.
3. It is very important that all solutions (should) be checked in the original equation.
6. We could also have used Theorem (6) to derive the result.
7. The requirement that energy (should) be conserved must be satisfied.
8. Everything here, be it a component or a device, is home-made.
III、
1. It was this scientist who/that discovered this phenomenon a century ago.
medium.
4. It is not clear yet under what conditions it is that this formula can be used.
5. This property we call inertia.
IV、
1. The author is engaged in the teaching
and recognition.
2. Let P and Q be two Boolean permutations of the same order, and then their composition is a new Boolean permutation.
3. Three algorithms are presented, which can remarkably reduce the time to raise the pen, thus raising the drawing efficiency.
4. What this paper describes is of great interest to communications engineers.
5. The minimum entropy technique for estimating the Doppler frequency rate is presented, which has the advantages over the classical techniques of high accuracy and a small amount of computation.
练习13
II、
1. By electromagnetic force is meant the potential difference across the battery when there is no flow of current.
2. In the table below/which follows are listed various parameters of familiar computers.
3. An element cannot be decomposed, nor can it be broken up by chemical methods.
4. Only when x = 8, does this equation hold/apply.
5. Of particular importance/Especially important are the two concepts which follow.
6. Such a set we call the mathematical system.
7. Rarely does one know this function with precision.
8. This interrelationship between electric and magnetic fields makes possible such things as the electromagnet and the electric motor.
9. Not until 1818 was the diffraction of light interpreted/explained.
10. By no means do electrons move from the positive terminal to the negative terminal in a wire.
II、
2. It is necessary to determine the charge on and the voltage across this capacitor.
3. In this case, no standard is needed, but only a numerical convention.
4. This voltage is greater than or equal to 0.4 volts.
5. The cathode, when heated, emits electrons.
6. Every body, whether accelerated or not, is considered (to be) in equilibrium.
7. If necessary, the wire will be covered with some insulation.
8. The transistor has its materials arranged p-n-p, hence the name pnp transistor.
III、
1. An initial analysis is made of the performance of the device.
2. The magnetic field is the space around a magnet occupied by the magnetic lines of force.
3. This leads to the battery voltage in the model of 500 mV.
4. This graph shows the variation with frequency of the resistance of the resistor.
5. This is responsible for the direct return to the atmosphere of more than half the water that falls on the land.
6. The question now arises how these unknowns can be determined.
7. It is necessary to determine the effect on the device of changing the ambient temperature.
8. The assumption has been made that the pressure always remains constant during the test.
IV、
1. The simulation results show that both the schemes are easy to implement.
2. The model and algorithm proposed in this paper are to a certain degree/extent superior in performance to the conventional BP algorithm.
3. A new technique for estimating the frequency deviation is proposed which gives a high accuracy and requires a small amount of computation.
4. Improvement of the accuracy of range alignment in ISAR imaging (by) using the super resolution technique
5. Research on and the realization of DTMF in a Cipher Coder
6. Analysis of the ability of a quartz flexibility accelerometer to resist bad environment
练习14
I、
1.then; Next
2.while
3.of course
4.However
5.In general; while
6.Hence
7.In fact
10.Instead
II、
It has been observed that bodies do not change their state of rest or motion until some other body forces them to do it. It is known form experiment that a body at rest tends to stay at rest unless a force is applied to make it move. A book lying on a table stays there unless a force is applied to move it. It is also known that any body, once (it is) in motion, will continue to move because of its inertia. To stop it a force must be applied by any other body.
III、
1. An analysis of the EMI spectrum at the input of the SMPS and its suppression
2. Also, a quantitative expression for the effect of all these factors on the performance of the system
3. This device can detect whether an IC functions properly or not/can detect the quality of an IC and
4. In this way, the area of an antenna site may be reduced to one-third that of the conventional one.
5. H and H’
练习15
I、
Semiconductors are a substance whose conductivity lies/comes/is between that of conductors and that of non-conductors. Common examples are silicon and germanium./Silicon and germanium are in
their conductivity. Therefore/Thus/So/As a result, semiconductors are widely used for automatically
II、
ξ1 andη3.
3. The features of this new algorithm are simplicity and objectivity.
4. It deserves to be further studied which nonlinear function should be selected.
5. The test of the system was conducted at a factory in Hong Kong with satisfactory results.
练习16
2. This point remains to be further studied.
3. In the previous section, we dealt with the composition of a computer.
4. It follows from this experiment that volume is inversely proportional to pressure.
5. This statement has been verified.
II、
1. This new method has many advantages over those available/over the existing ones.
2. The variation of pressure with temperature is obvious.
3. We can determine the response of the device to frequency.
4. This paper deals with the effect/influence/impact of EM waves on/upon human bodies.
5. This paper presents initial researches on fluids.
III、
1. Two other parameters are also very important.
2. This section introduces four additional/added kinds of instrument.
3. A robot is a special kind of electronic device.
4. We shall adopt a new set of parameters here.
5. This technology has reached the advanced world level.
6. Major theoretical developments in the 20th century are presented in this paper.
IV、
1. This cable has an approximate length of 20 meters/a length of approximately 20 meters.
2. These pipes have an average length of slightly/a little/a bit under/less than 5 meters.
3. Light has a speed through water of 224 million meters per second.
4. Any other sea does not have as high a salt content as the Dead Sea (does).
5. This force has a torque arm of zero.
6. These forms have the advantage that it is easy to see how the results are affected by changing the angles.
V、
1. some distilled water
2. the unknown substances
3. man-made satellites
4. amplitude-modulated signals
5. chromium-plated steel
6. the new racing cars
7. freely falling bodies
8. blue-lined paper
9. an acute-angled triangle
10. a wide-toothed saw
VI、
1. This method requires a much smaller amount of computation than that one (does).
2. This device consumes much less energy that that one (does).
5. Body A possesses more potential energy than body B.
6. This fluorescent screen displays clearer pictures than that one.
VII、
1. …… because of fairly low conductivity of the skin.
2. At temperatures greater than 80o C, …….
3. At/For/With constant pressure, …….
4. At/On/After the completion of all tests on the unit, …….
5. For/With small values of ω, ……
VIII、
1. Operation beyond this hyperbola will result in diode power dissipation in excess of its maximum rating of 1W.
2. Inclusion of the meter circuit in the feedback path minimizes the effects of diode nonlinearities on circuit performance.
3. Differentiation of this equation gives the following expression.
4. A temperature rise of 50o C/A rise in/of temperature by 50o C would damage the device.
5. The large size of the resistor makes it possible to neglect it.
6. Limited space allows only a brief discussion of quartz-crystal technology.
IX、
1. This fraction is rationalized by multiplying the numerator and denominator by the complex conjugate.
2. The addition of two complex numbers is accomplished by separately adding the real and imaginary parts.
3. The/Its solution is accomplished by first finding out I1.
4. These three parameters are related by the following equation.
5. V is related to t by Eq. (1–1).
X、
This paper presents a new design method, with emphasis on the guidelines of thought for its derivation. It has many advantages over those available [the existing ones]. Finally [Lastly], Its application is illustrated with an example.
XI、
1. Fig. 3 shows a transmission line with a length of I and a characteristic impedance of 500 Ω.
2. Although there are many ways to produce random numbers, the procedure for producing them is quite complicated.
3. As is known, when one reads a Chinese character, he or she does not consider every detail in it.
4. The Hash algorithm is a scheme by which data of any length can be compressed into data of a fixed length.
5. The number of times this value occurs in the observations is given in the first column.
练习17
I、
1. （略）
2. David J. Minot attended the University of California, Berkeley, CA. from 1994 – 1998. He earned the BS degree in botany there in 1998, and the M. Eng. Degree in electrical engineering from the University of Toronto, Toronto, Ontario, Canada in 2000. Since 2004 he has been working towards the Ph.D. degree in computer science at the University of Pennsylvania, Philadelphia, PA, USA.
In 1998 he served as a teaching assistant at the University of California. From 2000 to 2001 he was with the Moore School of Electrical Engineering, University of Pennsylvania. His research interests concentrate on the development of software.
II、
This device can identify whether an IC functions properly or not and it can determine the type of an unknown chip. It can test as many as more than 700 kinds of IC. It is characterized by easy operation, high testing speed and great portability. Its price is only about one-third that of the imported product of its kind/the same kind.
III、
1. It is important how the transmitting antenna pattern is determined./What is important is how to determine the transmitting antenna pattern.
2. δandδe can be obtained from Eqs. (3) and (4).
3. There are two factors controlling the diffusive signal process: (1) the diffusive signal, which can be
a brightness signal or a motion-matching signal; (2) the position of the diffusive signal, which determines where the diffusive process starts.
4. The following concept is one of the basic principles on which the neural system is based.
5. A method to increase the accuracy of range alignment by applying the forward-backward linear prediction is presented.
练习18
I、
1. Frequency is defined as the rate at which something occurs./By frequency is meant the rate at which something happens.
2. A thermometer is an instrument for measuring temperature.
3. Elasticity is defined as the tendency of an object to return to its original state after being deformed./By elasticity is meant the tendency ….
5. An electron is a particle with a mass of 9.107×10– 18 gram.
II、
The wavelet theory has so unique an advantage that it has found wide applications in many fields of engineering. Since this is the development and improvement of the Fourier analysis, it can, in principle, be used [A development and improvement of the Fourier analysis, this theory can, in principle, be used] where the traditional Fourier analysis is applicable. What is more, better results may be obtained on account of the fact that this theory overcomes the shortcomings of the Fourier analysis.
III、
1. This method imposes few limitations on the kinds of engineering drawings.
2. Because of the great difference in characteristic between these symbols, they are processed in different ways.
3. For these reasons, it is desirable for a computer to separate the text from the image.
4. These variations are so small that they can be neglected/so small as to be neglected.