安徽理工大学研究生英语第二学期翻译答案

V、练习参考答案

练习1

II、

1、an（人们对这课题的兴趣越来越浓。)

2、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（其主要的缺点是增加了噪声。）

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（频率的单位是赫兹。）

7、a; a; an; the（如果在电路的两端加上电压的话，就会有电流在电路中流动。）

8、/; /（图5－1画出了Oersted的实验。）

9、an（这里我们应该使用一个18伏的电池。）

10、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。）

11、The; /（水压机将在第14章加以考虑。）

12、The; the; the（研究处于运动中的流体，是力学中较为困难的分支之一，因为可能出现的现象是多种多样的。）

13、the; the [/]（我们容易确定参数μ的值。）

14、/; the（根据式（2－1），我们得到以下的关系式。）

15、an（在这里必须使用一根S形管子。）

16、the; /（作者工作在位于阿林顿的得克萨斯大学。）

17、an（这是一只R位的变换器。）

18、An（这里必须使用一个“异”或门电路。XOR = Exclusive OR）

III、

1.This is an h parameter.

2.We turn now to a discussion of local area networks.

3.The Bainbridge mass spectrometer is as important an instrument as the optical

spectrometer.

4.It is necessary to find out how long a time is required for an electron to travel the [this]

length of the wire.

5.The density of a substance is its mass per unit volume.

6.The radius of the earth is ×106 m.

7.The [These] two parameters are the same.

8.An increase in pressure always causes a decrease in volume.

9.Fig. (2-5) shows what is expressed by Eq. (2-2).

10.The unit of inductance is the henry.

11.Too large an input signal can cause nonlinear distortion.

https://www.360docs.net/doc/cf2605773.html,ing the definition of slope, we can derive the equation which represents a straight line.

13.The expression f (x＋h)－f (x) is frequently used in the study of calculus.

14.An equation which can be written in the following form is known as a linear equation in

one unknown.

15.In a computer, the tendency is to operate at as high a clock rate as possible.

16.Tin does not have as high a melting point as lead (does).

17.This average velocity is half the final velocity.

18.Electricity can be easily changed into other forms of energy.

19.In 1831, Joseph Henry in the United States discovered the phenomenon of

electromagnetic induction.

20.A computer consists of several parts [units].

IV、

Chemistry is based upon concepts that require the measurement of such quantities as length, volume, mass, and temperature. These measurements are quantitative; that is, they have numbers associated with them. In this section, we will consider some of the simple instruments used in quantitative measurements. We will also look at the units used to express these measured quantities.

V、

1.The UASMA protocol employs a unique frame structure.

2.Performance analysis an M-ary spread spectrum receiver using biorthogonal cyclic

codes

3.Finally, a broad stepped impedance transformer is designed by this method.

4.Dynamic analysis and evaluation of the security of a proactive secret sharing system

5.With the state-transition diagram, the security probability of the system is obtained.

6.the one-dimensional potential barrier with an arbitrary

profile.

7.We propose a numerical method based on Newton’s iterative method.

练习2

II、

1. Ordinary transformers are not ideal, and therefore power losses occur in them.

2. This material attracts iron objects and can even magnetize them.

3. This circuit consists of a battery, an inductor and a capacitor.

4. Compute the electric fields at points a, b, and c.

5. This satellite is used for communications between the United States and Great Britain, France and Italy.

6. Matter is anything like air, water or wood.

7. Assume that losses in the coil are zero, that C = 500μF, and that the ripple is 20 percent.

8. It is found more convenient to adopt the point of that a moving charge sets up a magnetic field, and that this field exerts a force on another charge moving through it.

9. Chapters 6, 7, and 8 deal with what is called the electronic brain.

10. Students may learn that mathematics is the language for scientific ideas, that science is a source of mathematical ideas, and that mathematics can furnish brilliant answers to important scientific problems.

III、

1. The current in the circuit is one half the short-circuit current of the source.

2. The internal resistance of this kind of storage battery is only a few thousandths of an ohm.

3. Its error is six parts in 1012.

4. This computer stores four times more information than that one (does).

5. The mass of the moon is 1/80 that of the earth.

6. The demand for this kind of equipment in the near future will be 20 times what it is.

7. The voltage across this component is a few tenths of a volt.

8. Now its internal pressure is one third what it was.

IV、

The concept of temperature is familiar to all of us. This is because our bodies are so sensitive to temperature differences. When we pick up a piece of ice, we feel cold because its temperature is lower than that of our hand. After drinking a cup of coffee, we may refer to it as “hot,”“lukewarm,” or “atrocious.” In the first two cases, at least, we are describing the extent to which its temperature exceeds ours.

V、

1. The voltage across this capacitor is a few hundredths of a volt.

2. This object is five times heavier than that one is.

3. Unless otherwise stated, it is assumed that silicon transistors are used and that I CBO can be neglected.

4. This circuit has the advantages of simple structure and easy adjustment.

5. Figs. 1, 2, and 3 show this process.

6. For further information, consult references [3, 5, 9].

7. The interior point is a minimum rather than a maximum, given that the return functions are convex, and that the Hessian determinant is positive.

练习3

II、

1. This type of computer has many advantages over that type.

2. We must solve this equation for the loop current.

3. Of these five new chapters, the first one deals with the basic principles of negative feedback.

4. This section introduces [presents] the concept of force.

5. This parameter varies [changes] with temperature.

6. The current and voltage in this circuit differ in phase by 90o. [The phases of the current and voltage in this circuit differ by 90o.]

7. Sound waves travel in all directions.

8. By analyzing [By the analysis of] the parameters of the instrument, we can understand its performance.

9. This is a sufficient and necessary condition for solving [the solution of] the equation.

10. We will find out its average velocity over this distance.

11. We measure force in newtons.

12. This paper introduces a new method for measuring this parameter.

III、

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 [to] the

equation, it was found that v is equal to the velocity of light.

3. In their study of electricity, physicists defined the parameter.

4. This circuit is similar in operation to that of Fig. 1-10.

5. In our discussion of this subject, we shall restrict our attention to its

basic principles.

6. We describe the interactions among charges with the help of the concept of electric field.

7. This is due in part to the earth’s rotation.

8. Upon [On] application of proper external force, the body will start to

move.

9. This computer is very small in size.

10. These waves travel only in one direction.

IV、

The common dry cell used in flashlights is constructed as shown in Fig. 2-28. The positive electrode is a carbon rod and the negative one is a zinc can. The cell is called “dry” because its electrolyte is a moist paste. If it were actually dry, ions in the electrolyte could not move about and no current could be produced. In the operation of the cell, zinc atoms become zinc ions by losing electrons.

V、

1. This paper presents a new method for the recognition of radar targets.

2. The influence of the moving state of the target on the tracking accuracy of the EKF is great.

3. This new method has many advantages over those available.

4. This newly designed instrument is good in quality [is of good quality].

5. Another comsat was launched on the morning of the 8th of October.

6. V oltage is measured in volts.

7. This experiment started at 8 o’clock last night.

8. They will leave for to attend an international conference on mobile communication.

练习4

II、

1. The answer (key) to this problem looks (appears) correct.

2. This coefficient remains to be determined.

3. The two equations below will be often (frequently) used in later chapters.

4. Here we use two metal balls 10 cm apart.

5. This paper contains (has) nothing new. [There is nothing new in this paper.]

6. The force acts perpendicular to the surface of the table.

7. This rule can be used for [ … can apply to] all integers, both positive and negative.

8. A neutron has a mass slightly larger than that of a proton. [… has a slightly mass than a

proton.]

9. Electrons are the smallest particles present in ordinary matter.

10. All the textbooks available discuss this problem.

11. Accurate in operation and high in speed, computers have found wide applications.

12. The input goes negative and [while] the output stays constant.

13. These rays seem to come from the image.

14. Impedance in an ac-circuit plays the same role that resistance does in a dc-circuit.

15. Two parallel wires a distance (of)δapart carry the current i.

16. The equations here are of great importance.

17. We shall use a cable 10 meters long.

18. The problem now is how to measure the voltage across this component.

19. These data will be sent to the computing center 2 kilometers away.

20. Upon rearranging the equation above, we have [get, obtain] the following expression.

21. That statement sounds quite reasonable.

22. Electrons can pass relatively unimpeded through metals.

23. The body collides with other bodies nearby.

24. These charges can interact with other charges present.

25. Forces can be transmitted without contact, contrary to the common belief.

26. There is no root larger than 1 [unity].

27. This coefficient is typically .

28. The charge is moving parallel to the electric field.

III、

The density of a substance is the ratio of its mass to its volume. Densities of liquids and solids are most often expressed in grams per cubic centimeter. Their densities can be found by measuring, independently, the mass and volume of a sample. For [With] solids, density is a bit more difficult to determine. A common approach is shown in Fig. . The mass of the sample is first measured (by) using [with] a balance. Its volume is found indirectly by determining the volume of liquid displaced by the solid.

IV、

1. This running machine will stop of itself in one or two minutes [… in a minute or two].

2. In this case, the input does not fall; nor [neither] does the output. […; the output does not fall, either.]

3. The resistance of a conductor depends not only on the material of which the conductor is made, but also on the size and temperature of the conductor.

4. These scientists are very interested in this topic.

5. This parameter can hardly be measured.

6. The preface to this book is well written.

7. In this laboratory, this instrument is more expensive than any other one. [… than any one else.]

8. The features of this device are small size and light weight.

练习5

II、

1. The detection process can be performed in either of the following two ways.

2. There is a capacitance across the junction. Its presence [existence] will cause problems at high frequencies.

3. This baseball will soon come to rest because of its interaction with the ground.

4. Our choice of this coefficient as 1 is correct.

5. This is due to its use of relays rather than electronic devices.

6. Since transformers are large, heavy, and expensive, their elimination from the circuit will result in considerable savings.

7. Emphasis is put on floated gyroscopes because their utilization [use] as a control component.

8. From its definition as the ratio of a force to a length, we can see that k has the same unit as work (does).

9. In this equation, that factor is Its inclusion here would merely complicate the proceedings.

10. In their discussion of that problem, scientists noticed this point.

11. Since feedback plays an important role in electronic circuits, its study is of great importance.

12. The black hole is invisible [cannot be seen], but its presence [existence] can be deduced.

13. Our analysis of the machine is of great significance.

14. This facilitates their use in circuit analysis.

15. The success in design depends on our correct choice of the circuit.

III、

1. Soon [Before long] we shall have computers the size of a watch.

2. This police car is equipped with a receiver the size of a matchbox.

3. Wires one hundredth the diameter of a silk thread are used to connect these components.

4. We must heat treat these tools.

5. In the past, telephone calls were operator connected.

6. This device is computer controlled.

7. This device is water resistant.

8. AC can be changed [turned, converted, transformed, translated] into [to] a process called [known as, referred to as] rectification.

9. A magnet attracts iron materials, a familiar phenomenon.

10. If this relation were to hold, we would have a negative current, an impossible situation.

something [a fact] that was verified experimentally by Ohm.

12. Computers are capable of processing a process that previously could be accomplished only inside our heads.

13. A new technology introduced in the 1960’s, laser can pierce the hardest substances such as diamond.

14. A very effective separation method, chromatography has found wide applications.

15. This aluminum bar m long has a rectangular cross section 1 cm by 5 cm.

16. This law applies to bodies the speed of a rocket.

17. We must frequency modulate it.

18. To solve this problem, we must take everything [all factors] into account, a very complicated procedure.

19. An instrument for measuring current, voltage, and resistance, the multimeter is widely used in electrical engineering.

20. These materials are pressure sensitive.

IV、

1. In the equations above, all h’s are the hybrid parameters.

2. Between times t2 and t3 the diode appears to be on.

3. In this circuit, there are three emf’s.

4. The mass of the standard pound is equal to kilograms.

5. All a’s and b’s in Eq. (5-1) are related to the impedance R o.

6. This section describes the advantages of AC over DC.

7. We must take the effect of temperature on [upon] semiconductors into

account.

8. In this case, the variation of output with input is very small.

9. This curve shows the dependence of distance on [upon] speed.

10. The use of the atomic energy as the source of power is very important.

11. The separation of impurities from the ore is very difficult.

12. We are all familiar with the definition of current as the flow of charge.

V、

Energy may be thought of as the ability to do work. When we say that something has energy, we mean that it is capable of exerting a force on something else and doing work on it. On the other hand, when we do work on something, we have added to it an amount of energy equal to the work done. The units of energy are the same as those of work. We shall consider in this chapter two broad categories of mechanical energy, kinetic energy and potential energy.

VI、

1. Other types of series are also widely used in engineering.

2. None of them can solve this special type of differential equation.

3. They do not know whether this material can stand so large a force or not.

4. The machine will automatically start to operate again in two hours.

5. There are M polygons altogether, each of which has N vertexes.

6. The advantages of this method over the scanning method have also been discussed.

7. These two engineers are busy (in) designing a new kind of software.

8. Iron is almost as good a conductor as aluminum.

练习7

II、

1. All we need to do is (to) measure the pressure on the body. [或：All that is necessary is to measure …; It is only necessary for us to measure …; We need only to measure ….]

2. It is quite possible for them to solve this equation.

3. It will take a few months to design this kind of aircraft with the help of a computer.

4. If it is desired to find out this force, we may use the parallelogram method.

5. It is left as a problem to [for] the reader to show that this expression hold.

6. The program to be executed is stored in this unit.

7. This valley acts as the foundation on which to build the dam.

8. In this laboratory there are many kinds of instrument for students to choose from.

9. Atoms are too small for us to see with our naked eyes.

10. Let it be required to find out this component.

11. Let t0 equal [be equal to] zero.

12. The farther away the target (is), the longer time it takes for the echo to return.

13. We find this problem easy to solve.

14. It is necessary to solve this equation for x.

15. For the series to converge, x must be less than 1.

16. We find this concept very difficult to understand.

17. This method makes it much easier to detect targets.

18. Time-shared systems are expensive to build.

19. This factor will affect the ability of a computer to store information.

20. We have to find out how large to make r so as for the series to converge.

21. This is a pen to draw pictures with.

22. For the transistor to conduct, its base must be about volts.

23. Elasticity is the tendency of a body to return to its original condition after being deformed.

24. An antenna is a device to transmit and receive radio waves.

25. The lack of such protection has made it easy for malicious programs to destroy data on systems.

26. These problems deserve to be further studied.

27. We consider it necessary to make measurements with accuracy.

28. R is the resistance to be measured.

29. Each member has a switch with which to indicate a YES or NO vote.

30. Ordinary matter is said to be electrically neutral.

property makes it possible for metals to be made into any shape.

32. This table is unfit for a student to do experiments on.

33. Now we consider what path of integration to take.

34. In this case, the time necessary for the current to reach its maximum value is changed.

35. The purpose to write this book is to give the reader a brief introduction to electronic computers.

III、

The period with which a body undergoes simple harmonic motion is the time required for it to make one complete oscillation. In the case of a spring [For a spring], the period is the time the spring spends in going from its maximum extension, through its maximum compression and back to its maximum extension once more. For all types of simple harmonic motion, the period T is given [expressed; denoted; represented] by

S/,

T = 2πa

where the acceleration a is that experienced by the body when it is at its specified position.

IV、

1. The sine law of the variation of the cylinder diameter with light intensity has been emphasized.

2. Our method is different from those described [presented] in the papers available on [discussing] the same problem.

3. To do all this, a sound knowledge of computer science is necessary. […, it is necessary to have a sound knowledge of computer science.]

4. Not only do temperature and light affect the conductivity, but the addition of impurities to semiconductors also makes it change greatly.

5. Various satellites are frequently launched to obtain information about [on] space.

6. Our semiconductor industry came into being at the end of the 1950s.

7. Direct current flows always in one direction.

8. My colleagues and I would like to express our thanks to Professor W. Smith for his great help.

练习8

II、

1. The compressed air has the ability to do work.

2. The presently existing integration methods do not apply [hold] here.

3. The amplifier amplifies the received signals.

4. Moving molecules have kinetic energy.

5. Fig. 1 – 3 shows the photo of a freely falling body.

6. Speed equals distance divided by time.

7. V oltage equals current multiplied by resistance.

8. The resistance of air increases with the increased [increasing] speed.

9. A transformer is a device consisting of two or more coils wound on [round] an iron core.

10. It is necessary to find out the current flowing through this component.

11. This book, properly used, will be of great help to the reader.

12. Flowing through a circuit, the current will lose part of its energy.

13. In this case, electrons have more energy, (thus) increasing the brightness of the light spot.

14. Given [Knowing] time and speed, we can find out distance.

15. Having studied this chapter, the student will understand the principle of a computer.

16. The speed of light being extremely great, we cannot measure it by ordinary methods.

17. Several comsats were launched, all of them (being) high-altitude satellites.

18. Called “the mother of all networks,” the Internet is a widely used international network.

19. The angle in radians, being defined as the ratio of a length to a length, is a pure number.

20. This force can be resolved into two components, one (being) horizontal and the other vertical.

III、

1.With the switch closed, the balance point is found by trial and error.

2.With both speakers on, what is the intensity at C?

3.The Internet Protocol was not designed with security in mind.

4.Let us construct [draw] a circle with the origin as the center and of

radius R.

5.The equation to the circle of radius r with the center at the origin is x2 +

y2= r2.

6.This parameter should be measured with E grounded.

7.Its Fourier transform can be obtained from Eq. (2 – 4), with the lower

limit replaced by zero.

8. With no resistance in the circuit, the current will increase indefinitely.

9. With no input present, the output will be zero.

10. With this in view, we have written this book.

IV、

1.Let us consider designing a voting machine.

2.Blood is capable of being broken down into various components.

3.Multiplying a and b together to give e may be written as a×b = e.

4.We refer to these components as being passive.

5. A cell reproduces by dividing in two.

6.This involves taking the Fourier transform.

7.The light beam will be deflected upon entering the medium.

8.On rearranging the above equations, we obtain the following set of

equations.

9.In using this equation, it does not matter which plane is considered as

1.

https://www.360docs.net/doc/cf2605773.html,pressing a gas quickly raises its temperature.

11.This machine needs repairing.

12.This book is worth reading.

V、

Let us begin our study of electricity by examining the results of a few basic experiments. The first experiment consists of stroking a rubber rod with some fur, and then in turn touching two small pith balls suspended from strings with the rod. The pith balls then swing apart, indicating that a repulsive force now acts between them. Next, we stroke a glass rod with a silk cloth and touch two different suspended pith balls in turn with it. Once more the pith balls swing apart, indicating a repulsive force. Now we bring near each other one of the pith balls touched with the rubber rod and one touched with the glass rod; they swing toward each other this time, indicating an attractive force.

VI、

1.The results obtained indicate that these two methods are consistent in

essence, with the exception that they have their own specific application conditions.

2. A new algorithm has been designed which will be able to maintain the

survival of useful copies, thus greatly reducing the number of packet copies in a network.

3. Given [Knowing] resistance and current, one [we] can determine voltage.

4. The price of this instrument is high.

5. This device occupies too much space/room.

6. A robot is a special kind of electronic device.

7. This scientist said, “Electrons move round the nucleus.”

8. The current starts flowing at the very moment we close the circuit.

9. There are a few exceptions to this rule.

10. They have been designing a new type of computer these six months.

练习14

I、

1. 主题句：第一句；结论句：最后一句。

2. 整个一小段[只有一句话]为主题句。

3. 主题句：第一句；本段没有结论句。

4. 主题句：第一句；本段没有结论句。

II、

1.then; Next

2.while

3.of course

4.However

5.In general; while

6.Hence

7.In fact

8.For instance

9.but; However; namely [that is]

10.Instead

III、

One of the fundamental properties of matter is inertia, the Latin word “inertia”meaning laziness.

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.

IV、

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 is derived, on the basis of which an improved system is presented.

3. The performance of the system has been improved (by) 14～30dB on condition that the complexity of the system remains unchanged.

4. Measurements are generally of three groups: those made of capacitance, those made of current and those made of voltage.

5. This device can detect whether an IC functions properly or not [can detect the quality of an IC] and identify the type of an unknown chip.

6. his paper deals with the extension of the RELAX algorithm from data domain to correlation domain.

7. The principle of the digital correlator is introduced, with its spectrum de-extension performance in the spectrum extension system analyzed.

8. In using this Pascal program, all the user needs to do is (to) input the graph model of his or her applied problem so as to get its solution displayed on the computer system.

9. In this way, the area of an antenna site may be reduced to one-third that of the conventional one.

10. H and H’ must satisfy the conditions of Theorem and Theorem when embedded in Fig.

5.

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 common use]. Semiconductors are quite sensitive to heat and light, both of which have a great effect on their conductivity. Therefore [Thus; So; s a result], semiconductors are widely used for automatically counting parts on conveying belts and for many other purposes. II、

1. In this case, we consider joining ξ1 andη3.

2. This new algorithm maintains the advantage of finding he optimal routes very quickly.

3. This paper presents a new approach to realizing multi-point communication with the MC145442 one-chip modem manufactured by the MOTOROLA CO.

4. Let G be an . graph with 4n vertices, and then the spanning subgraph H* of G is a graph.

5. This circuit can be easily cascaded to obtain high-order current-mode filters.

6. It takes only 5 iterations to obtain the result by using this algorithm, which are far fewer than 250 iterations required to obtain the same result by using the traditional algorithm.

7. The features of this new algorithm are simplicity and objectivity.

8. It deserves to be further studied which nonlinear function should be selected.

9. This process is very similar to the one by which a fluid flows from one vessel through a neural network to another.

10. The test of the system was conducted at a factory in Hong Kong with satisfactory results.

练习16

I、

1．This paper presents a new temperature-measuring method, with emphasis on its basic principles.

2. The results obtained indicate that this method is very effective.

3. This point remains to be further studied.

4. This problem will be discussed in the next chapter.

5. In the previous sections, we dealt with the composition of a computer.

6. It follows from this experiment that volume is inversely proportional to pressure.

7. This statement has been verified.

8. All these values of x do not satisfy the equation.

9. This depends to some extent on the bandwidth of the signal.

10. Gamma rays are entirely different in nature from alpha rays.

11. This force is due solely to the electrostatic field.

12. This kind of machine consists generally of six parts.

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 coefficient is defined as the ratio of a length to a length.

5. The change [conversion; transformation; turning; translation] of AC into [to] DC is very easy.

6. The exposure of the human body to the sunlight is beneficial to the health.

7. This paper deals with the effect [influence; impact] of EM waves on [upon] human bodies.

8. The preface to this book is well written.

9. The approach to measuring wind speeds has been widely adopted.

10. This paper presents initial researches on fluids.

III、

1. A comparison of this method with the existing ones is made.

2. A brief introduction to several new concepts is given in this section.

3. The control of temperature is effected by the use of this device.

4. This parameter is an indication of the amount of amplification of a transistor.

5. Fig. 1-8 gives an illustration of the process of signal transmission.

IV、

1. Each computer section will be introduced in detail.

2. Two other parameters are also very important.

3. This section introduces four additional kinds of instrument.

4. A robot is a special kind of electronic device.

5. We shall adopt a new set of parameters here.

6. This symbol stands for the negative battery terminal.

7. This technology has reached the advanced world level.

8. This paper presents the main theoretical developments in the 20th century.

9. Many computer applications are summarized as follows.

10. There is a long piece of wood here.

V、

1. This cable has an approximate length of 20 meters. […a length of approximately 20 meters.]

2. This piece [sheet] of paper has a width of 50 centimeters.

3. These pipes have an average length of slightly [a little; a bit] under [less than] 5 meters.

4. Diamond has an index of refraction of .

5. The moon has a radius of 1736 kilometers.

6. Light has a speed through water of 224 million meters per second.

7. Sea water has a higher [greater] content of manganese than fresh water (does).

8. Any other sea does not have as high a salt content as the Dead Sea (does).

9. China has a much larger population than any other country in the world.

10. This liquid does not have as low a freezing point as water (does).

11. Doing so has an additional [another] advantage of reducing the amount of numerical computation.

12. This battery has a negligible internal resistance.

13. The positive charge of the proton has the same magnitude as the negative charge of the electron.

14. This force has a torque arm of zero.

15. These forms have the advantage that it is easy to see how the results are affected by changing the angles.

16. CMOS gates have a much higher noise margin than TTL gates (do).

VI、

1. some distilled water

2. an incorrectly designed bridge

3. the unknown substances

4. an unsolved problem

5. man-made satellites

6. amplitude-modulated signals

7. chromium-plated steel

8. wind-driven pumps

9. the instruments used

10. the number of mistakes found

11. the new racing cars

12. drawing paper

13. freely falling bodies

14. an oil-producing country

15. the boiling point

16. material thus/so tested

17. blue-lined paper

18. an acute-angled triangle

19. a wide-toothed saw

20. a three-legged stool

VII、

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).

3. This lamp gives off much brighter light than that one.

4. We should use as simple a structure as possible.

5. It is generally possible to write down more node and loop equations than

(are) needed.

6. This factory manufactures machines of good quality.

7. We have obtained satisfactory results.

8. Body A possesses more potential energy than body B.

9. This fluorescent screen displays clearer pictures than that one.

10. This book discusses many topics.

VIII、

1. …… because of fairly low conductivity of the skin.

2. At temperatures greater than 80o C, …….

3. ……because of their great speed and their adequate accuracy.

4. For/With relatively large forward currents, ……

5. At/For/With constant pressure, …….

6. During compacting/compactification, (a) considerable lateral pressure is exerted by the concrete.

7. At/On/After the completion of all tests on the unit, …….

8. For/With small values of ω, ……

IX、

1. Reduction of the charging-time constant will improve both bandwidth and sampling efficiency.

2. Operation beyond this hyperbola will result in diode power dissipation in excess of its maximum rating of 1W.

3. Application of a current pulse in the opposite direction reverses the magnetization.

4. Comparing [Comparison of] Eq. (1 – 2) with Eq. (1 – 3) shows that such a phase shift would result in system oscillation.

5. The removal of that current does not guarantee that the galvanometer will return to its initial position.

6. Substituting [Substitution of] this number in Eq. (9 – 4) yields [produces; gives; results in; leads to] the following expression.

7. Inclusion of the meter circuit in the feedback path minimizes the effects of diode nonlinearities on circuit performance.

8. Differentiation of this equation gives the following expression.

9. Increasing the thickness of the lagging will reduce the heat losses.

10. The testing of machines by this method will entail/result in some losses of power.

11. A study of these listings will greatly help the programmer in finding any errors made in writing the program.

12. A temperature rise of 50o C [A rise in/of temperature by 50o C] would damage the device.

13. A cascade of such seven gates would yield an output of only V.

14. The large size of the resistor makes it possible to neglect it.

15. Limited space allows only a brief discussion of quartz-crystal technology.

15. The deflection of electrons by an electric field is used to control the direction of an electron stream in many electronic devices.

X、

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).

XI、

1. This oscillator is linearly tunable over the range of 2 to 3GHz.

2. This distortion is usually acceptable.

3. The analyzer is a representation [representative] of the superheterodyne type.

4. This example is an illustration [illustrative] of the fact that an ideal inductor behaves as a short circuit to dc.

5. Isolators are useful [usable] as stabilizers.

6. This multiplier is calculable [computable].

7. Relative values of the various harmonics can be indicative of the nature of the phenomenon.

8. In most practical situations, the system output signal is not visible directly.

9. This term is descriptive of FM (frequency modulation).

10. This number is divisible by 8.

XII、

1. 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.

2. Radar is used for determining by radio echoes the presence of objects, their directions and ranges. A radar set consists mainly [chiefly; principally]of six units.

When the transmitted energy strikes an object, a portion [part] of it is reflected back, thus enabling the receiver to receive the echo and transform [convert; change; turn; translate] it into a visual [visible] signal. The timer measures the time [time period] that elapses between the transmission of the signal and the reception of its echo. The distance of the radar set from the target [from the radar set to the target] is half the time [time period] multiplied by the speed of light [half the time period times the speed of light; half the product of time period and speed of light].

XIII、

1. We can solve equation (3) for αn, thus obtaining U o.

2. Fig. 3 shows a transmission line with a length of I and a characteristic impedance of 500 Ω.

3. Although there are many ways to produce random numbers, the procedure for producing them is quite complicated.

4. As is known, when one reads a Chinese character, he or she does not consider every detail in it.

5. We have obtained a recognition rate of %.

6. After being processed, these data are sent to the database server immediately.

7. We have also developed an algorithm for recording the changes of tables.

8. The Hash algorithm is a scheme by which data of any length can be compressed into data of

a fixed length.

9. Unlike what was described in literature [reference] [2], g and u are not evenly distributed.

10. 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 . 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、

1. This paper outlines some problems on/about/concerning the application at home and abroad in recent years of the optimization theory in the design of antenna structures. They play an important role/part in both raising the effectiveness of designing antenna structures and improving the performance of an antenna. Also/In addition/Besides/What is more, this paper presents several problems which remain to be solved in the design of antenna structures.

2. The electric waveguide structure, with which a great number of passive and active devices have been developed, ha found various applications in millimeter-wave integrated circuits. This paper gives an introduction to the method of designing directional couplers using dielectric waveguides, with some simplified and effective formulae presented. Finally, the application of this method is illustrated with an example.

3. 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.

4. Mercury is the smallest of the nine major planets. Its average distance from the sun is approximately million kilometers. It takes only 88 days to complete one revolution. Its mass is one-twenty-ninth that of the earth. It has no atmosphere.

III、

1. To reduce the interval between elements, it is necessary to increase the number of elements of the array.

2. It is important how the transmitting antenna pattern is determined./What is important is how to determine the transmitting antenna pattern.

3. δandδe can be obtained from Eqs. (3) and (4).

4. For every point, there are only two features available.

5. 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.

6. The following concept is one of the basic principles on which the neural system is based.

7. There are some basic differences between this system and the BSC.

8. A method to increase the accuracy of range alignment by applying the forward-backward linear prediction is presented.

IV、

For the convenience of discussion, let the projection vector be the Z-axis, and therefore, the corresponding Y-axis is the cross-range axis.

A method for reducing the cross terms of WVD effectively but having a little effect upon signal terms is presented in this paper. Because each signal term has the characteristic of a straight line in the Wigner plane, signal terms appear as sharp peaks and cross terms are distributed in a wide area when the signal is transformed into the Hough plane.

From Fig. 4, we can see that the two signals’ auto-terms look like a butterfly and that cross terms’ magnitudes are low and distributed in a wide area. The WVD slice at the moment t = 0 restored by integration according to Eq. (10) may basically keep the principal components of the signal and reduce the cross term greatly. Furthermore, for multiple signals with almost an equal magnitude and different parameters, the RWT filtered in the Radon-Wigner plane will have /produce sharp peaks at the corresponding points.

Because of the fact that the strong suppresses the weak, in principle, the next component cannot be determined precisely. If we eliminate the component z 1(t) from z (t), the second component may stand out. How can we eliminate z1(t)?

The radar works in the C-band. The targets are AN-26 and YAK-42 aircraft.

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. Gravity is a force which pulls an object towards the center of the earth. / By gravity is meant the force which ….

3. A tape-recorder is a machine /a tool/an instrument which records sounds.

4. A thermometer is an instrument for measuring temperature.

5. Linear operation is defined as the ability of an amplifier to amplify signal with no distortion. / By linear operation is meant the ability ….

6. Elasticity is defined as the tendency of an object to return to its original state after being deformed. / By elasticity is meant the tendency ….

7. An isosceles triangle is a triangle/ one having two equal sides/having two sides equal in length/with two sides equal in length.

8. An electron is a particle with a mass of ×10– 18 gram.

9. The S/N ratio is defined as the ratio of signal to noise.

10. A laboratory is a place where experiments are made.

II、

1. This paper discusses some of the problems facing/concerning/connected with the nonsinusoidal electromagnetic wave radiation. At present, This system is low in efficiency, not high enough in signal fidelity, and not so good in directivity so that its applications/the areas for applications are limited.

2. 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. A single process is enough for us/one to obtain a satisfactory/satisfying result.

2. This method imposes few limitations on the kinds of engineering drawings.

3. Because of the great difference in characteristic between these symbols, they are processed in different ways.

4. For these reasons, it is desirable for a computer to separate the text from the image.

5. The wavelet transform is well adapted to characterizing transient phenomena.

6. These variations are so small that they can be neglected/so small as to be neglected.

7. This is beneficial not only to distinguishing signal terms from each other, but also to reducing cross terms.

8. Is it possible for us to construct an LFM signal?

IV、

In recent years, great progress has been made in optical character reading technology, in which the image to be recognized may be mixed with a text, a graph, or a gray picture. The original binary image usually contains more than one kind of information symbol.

In this paper the text/graphics seapartion problem in the recognition of binary drawings has been discussed. By engineering drawing we mean a mechanical drawing, a geographic map, a program chart, etc. Conventional research work on text/graphics separation is described in literature [1]-[7].

The text should be printed, and it should seldom touch graphics. It is preferably written vertically or horizontally, not in any other direction. The text should not contain any Chinese characters. These assumptions limit the applications greatly/a great deal/a lot. The interactive modification will have to be made, which is labor-intensive and time-consuming.