1. We must leave home two hours before the plane taking off so that we can get to the airport without hurrying. 2. This car needs fuelling every 300 miles. 3. The first steps in designing robot engine driver for heavy high-speed trains were made in 1960s. 4. Mechanical loading wagons results in considerable saving of time. 5. The transport committee studied the problem of increasing the number of buses operating on the city’s routes. 6. They started working without another word being spoken on either side.

Exercise 2 . Translate the following sentences paying attention to the preposition + - ing phrases:

1. I wonder at your overcoming these difficulties so easily. 2. The rule against visitors entering the lab at the time of the experiment is strict. 4. The film serves to demonstrate a new approach in using the computer. 5. Scientists invented another interesting device for testing materials at high temperatures. 6. Each train automatically identifies itself by generating a unique frequency. 7. These installations are being used in connection with the moving of freight cars. 8. It was necessary for railroads to introduce an interlocking system to prevent two trains from receiving a processed signal at the same time. 9. Before crossing the road, stop and look both ways. 10. There is no need for us to tell you about the importance of installing the signal appliances at railroads.

READING   

Text

AUTOMATED SYSTEM

Every automated machine or system requires four basic components: l) power source, 2) sensing mechanisms or feedback, 3) decision element and 4) control element.

The power source (e.g. batteries or electric generator) provides an automated system with the energy needed to achieve its desired task.

The sensing mechanism enables the system to measure some property of the output; photoelectric cells, thermocouples, X-ray machines, and electrical meters being typical sensing mechanisms. The properties they may measure include dimensions, weight, temperature, pressure, colour, or electrical resistance. This element is called feedback because the instruments return or feedback this information to the central system control.

The decision element compares the data supplied by the sensing element with standards stored in the program, this step being often carried out by a computer. If some action is necessary, the decision element gives the instructions to the system.

The control element carries out the commands of the decision element and keeps the system in conformity with its program. The control element may consist of switches that control the flow of electricity, valves, or other mechanisms.

The power source and the sensing mechanism or feedback, decision and control elements operating properly, an automated system is able to regulate its behaviour.

Modern automated railways may have hundreds or even thousands of interconnected feedback loops.

in conformity with – в соответствии с

feedback loop – контур обратной связи

Exercise 3. Find in the text English equivalents to the following words:

автоматическая система, источник питания, механизм считывания, свойство, выходные данные, решающий элемент, управляющий элемент, обратная связь, контур обратной связи, переключатель.

Exercise 4. Complete the following sentences and translate them.

1. Every automated system requires… .

2. The power source provides… .

3. The sensing mechanism usually measures… .

4. It is called feedback because

5. Typical sensing mechanisms are... .

6. The decision element is usually ... and it... .

7. Control element, carries out... .

8. It consists of... .

9. Modern automated railway… .

Exercise 5. Give a short summary of the text. The following phrases may be helpful:

Lesson 4

GRAMMAR. Gerund. Forms. (Grammar Comment §2).