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Electric power and machinery




The field of electric power is concerned with the design and operation of systems for generating, transmitting, and distributing electric power. Engineers in this field have brought about several important developments since the late 1970s. One of these is the ability to transmit power at extremely high voltages in both the direct current (DC) and alternating current (AC) modes, reducing power losses proportionately. Another is the real-time control of power generation, transmission, and distribution, using computers to analyse the data fed back from the power system to a central station and thereby optimizing the efficiency of the system while it is in operation. A significant advance in the engineering of electric machinery has been the introduction of electronic controls that enable AC motors to run at variable speeds by adjusting the frequency of the current fed into them. DC motors have also been made to run more efficiently this way.

Вариант 5.

I. Перепишите предложения, раскрыв скобки и употребив глагол в соответствующей временной форме группы Perfect Active и Passive. Переведите.

1. That man (stand) at the bus stop for the last half hour. Shall I tell him that the last bus already (go)?

2. When we came out of the restaurant, we saw that our car (disappear).

3. A special edition for children (be written) by the author.

4. Helen (learn) English since last autumn.

II. Перепишите следующие предложения; подчеркните в них модальные глаголы и их эквиваленты. Переведите предложения на русский язык.

1. Do I have to pay in cash next week or can I give you a cheque?

2. People shouldn’t be allowed to park there.

3. These factors are not to be considered the most important in helping us to improve the quality of the service.

4. I’m afraid that he won’t be able to come back in time.

III. Перепишите предложения, раскрыв скобки и употребив глагол в придаточных предложениях времени и условия в соответствующей форме.

1. I shan’t buy tomatoes till the price (come) down.

2. After the plane (land) you may unfasten your belts.

3. If you (not go) away I’ll send for the police.

4. Unless I have a quiet room I (not be able) to do any work.

IV. Перепишите следующие предложения; подчеркните Participle I, Participle II и Gerund. Переведите предложения на русский язык.

1. You’d better consult your lawyer before deciding to buy the property.

2. Having been advised by the doctor to go to the south, she decided to spend her leave in Sochi.

3. A balsa tree found in South America is lighter than any other.

4. The tree unrooted by the gale, had fallen across the road.

V. Переведите предложения на английский язык.

1. Подписано ли это письмо?

2. В котором часу вы должны быть в институте завтра?

3. Если он не придет завтра, пошлите ему телеграмму.

4. Рабочие, разгружающие пароход, будут свободны через час.

VI. Прочитайте и переведите текст.

Electronics

Electronic engineering deals with the research, design, integration, and application of circuits and devices used in the transmission and processing of information. Information is now generated, transmitted, received, and stored electronically on a scale unprecedented in history, and there is every indication that the explosive rate of growth in this field will continue unabated.

Electronic engineers design circuits to perform specific tasks, such as amplifying electronic signals, adding binary numbers, and demodulating radio signals to recover the information they carry. Circuits are also used to generate waveforms useful for synchronization and timing, as in television, and for correcting errors in digital information, as in telecommunications.

Prior to the 1960s, circuits consisted of separate electronic devices – resistors, capacitors, inductors, and vacuum tubes – assembled on a chassis and connected by wires to form a bulky package. The electronics revolution of the 1970s and 1980s set the trend towards integrating electronic devices on a single tiny chip of silicon or some other semiconductive material. The complex task of manufacturing these chips uses the most advanced technology, including computers, electron-beam lithography, micro-manipulators, ion-beam implantation, and ultraclean environments. Much of the research in electronics is directed towards creating even smaller chips, faster switching of components, and three-dimensional integrated circuits.

Вариант 6

I. Перепишите предложения, раскрыв скобки и употребив глагол в соответствующей временной форме группы Perfect Active и Passive. Переведите.

  1. That man (stand) at the bus stop for the last half hour. Shall I tell him that the last bus already (go)?

2. When we came out of the restaurant, we saw that our car (disappear).

3. A special edition for children (be written) by the author.

4. Helen (learn) English since last autumn.

II. Перепишите следующие предложения; подчеркните в них модальные глаголы и их эквиваленты. Переведите предложения на русский язык.

  1. He’ll have to look for another job.

2. The police were suspicious at first but I was able to convince them that we were innocent.

3. When he was a child he was allowed to do exactly as he liked.

4. He was not allowed to enter the concert hall after the third bell.

III. Перепишите предложения, раскрыв скобки и употребив глагол в придаточных предложениях времени и условия в соответствующей форме.

  1. When he (return) I’ll give him the key.

2. When he (sell) his newspapers he’ll go home.

3. If he (not phone) this afternoon I’ll phone him this evening.

4. If I lend you 10 pounds when you (repay) me?

IV. Перепишите следующие предложения; подчеркните Participle I, Participle II и Gerund. Переведите предложения на русский язык.

1. Raising the output we must not forget the task of improving the quality at the same time.

2. Engineers find use for titanium and prefer it to aluminium which loses its strength rapidly when subjected to high temperatures.

3. The Moon, like the Earth, shines with the reflected light of the Sun.

4. All the difficulties in organizing the laboratories and in supplying them with the necessary equipment had to be overcome.

V. Переведите предложения на английский язык.

  1. Мы уже пообедали, когда он пришел.

2. Телеграмму нет необходимости посылать сегодня.

3. Этот вопрос должен быть решен до того, как соглашение будет подписано.

4. Я помню, что встречал его где-то.

VI. Прочитайте и переведите текст.

Mechanical Engineering

Engineers in this field design, test, build, and oper­ate machinery of all types; they also work on a variety of manufactured goods and certain kinds of structures. The field is divided into (1) machinery, mechanisms, materials, hydraulics, and pneumatics; and (2) heat as applied to engines, work and energy, heating, ventilat­ing, and air conditioning. The mechanical engineer, therefore, must be trained in mechanics, hydraulics, and thermodynamics and must know such subjects as metallurgy and machine design. Some mechanical en­gineers specialise in particular types of machines such as pumps or steam turbines. A mechanical engineer de­signs not only the machines that make products but the products themselves, and must design for both economy and efficiency. A typical example of modern mechani­cal engineering is the design of a car or an agricultural machine.

Safety Engineering

This field of engineering has as its object the preven­tion of accidents. In recent years safety engineering has become a specialty adopted by individuals trained in other branches of engineering. Safety engineers develop methods and procedures to safeguard workers in hazard­ous occupations. They also assist in designing machin­ery, factories, ships and roads, suggesting alterations and improvements to reduce the possibility of accident.

In the design of machinery, for example, the safety en­gineer try to cover all moving parts or keep them from accidental contact with the operator, to put cutoff switches within reach of the operator and to eliminate dangerous sharp parts. In designing roads the safety engineer seeks to avoid such hazards as sharp turns and blind intersections that lead to traffic accidents.

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