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Методические указания и учебные задания по профессиональноориентированному чтению для студентов 2 курса технических специальностей


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НазваниеМетодические указания и учебные задания по профессиональноориентированному чтению для студентов 2 курса технических специальностей
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scientists care for investigating and exploring the world?

  1. Express your opinion on the problem discussed in the text.

MODULE II. COMPUTER ESSENTIALS UNIT 1. COMPUTER AS IT IS Lesson 1. Computers

  1. Read and memorize the following words and combinations: physical quantities - физические величины

device
- прибор, устройство, механизм

to measure - измерять

numerical value - численное значение

incredible - невероятный, немыслимый

ability - способность

to add - прибавлять, складывать

to subtract - вычитать

to multiply - умножать

to divide - делить

human brain - человеческий мозг

solution - решение

circuit - электронная схема, микросхема to clock - заводить, запускать

  1. Read and translate the text.

There are two types of computers, the analogue and the digital. Basically, today’s analogue computer is a device for measuring such physical quantities as lengths and voltages and, through a mechanical linkage, exhibiting the measurement as a numerical value. However, the analogue computer is limited to special classes of problems and when most people say “computer” today, they mean the digital computer which is a marvel of precision and accuracy, for it works with specific units rather than approximations.

The modern electronic digital computer counts with incredible speed using only two numbers — the one and zero what mathematicians call the binary system. The counting ability of the computer is used to feed it information. But first the information is translated into a code.

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The information is then stored in a memory bank made of magnets. The direction in which electrical signals run through the magnets means one or zero, yes or no, off or on. Each magnet contains one piece of information called a bit. A large computer system can store hundreds of millions of such information bits.

But information by itself is useless. The computer must be told what to do with it — to add, subtract, multiply, or divide the coded pulses stored in its memory. Parts of that memory contain instructions, prepared by a human brain, that provide the computer with the road to follow in order to solve a problem. These instructions are called the program.

What makes the computer different from an adding machine is that the computer can modify its instructions.

If a problem cannot be solved by following one route, the computer can search its memory for another set of instructions until a solution is found. And it does all this at superhuman speeds. The on-off switching of the computer’s logic circuits has been clocked at a billionth of a second. That is to one second what one second is to thirty years.

But the computer cannot actually think. It performs all of its functions by route. Once an answer is achieved, another program within the memory tells the computer how to display the solution, to type it out on paper, display it as pictures or words on a television screen, or perhaps even to speak the answer in words a man can hear.

Notes

A marvel of precision and accuracy - чудо четкости и точности. It performs all of its functions by route. - Он выполняет все свои функции по программе.

  1. Give the Russian equivalents.

Analog computer is a device for measuring physical quantities, to count with incredible speed, the counting ability, a piece of information called a bit, information by itself is useless, superhuman speeds, the computer cannot actually think.

  1. Give the English equivalents.

Физические величины, численное значение, чудо четкости и точности, двоичная система, сотни миллионов бит информации; складывать, вычитать, умножать или делить; инструкции, подготовленные человеческим мозгом; включение и выключение компьютерных схем.

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  1. Fill in the blanks.

1. In fact the analogue computer /ограничен/ to special classes of problems. 2. The counting ability of the computer /используется/ to feed it information. 3. First the information /переводится/ into a code. 4. The information /хранится/ in a memory bank made of magnets. 5. The computer /нужно сказать/ what to do with information. 6. These instructions /называются/ the program. 7. If a problem /не может быть решена/ by following one route, the computer can search its memory for another set of instructions. 8. Once an answer /получен/, another program tells the computer how to display the solution.

  1. Answer the following questions.

  1. What are the two types of computers? 2. What is today’s analog computer? 3. What device do most people mean when they say “computer”? 4. How many numbers does the so-called binary system use?

  1. Where is information stored inside a computer? 6. What do we call a magnet containing one piece of information? 7. How many information bits can a large computer system store? 8. What does the computer use its counting ability for? 9. Is information useful by itself? 10. Who prepares instructions for the computer? 11. What is program? What makes the computer different from the adding machine? 12. Explain the word combination “superhuman speed”. 13. What is the difference between the computer and the human brain?

  1. Give a brief summary of the text.

  2. Read the text and translate it without a dictionary. Write a short summary of it.

What a computer is

The term “computer” is used to describe a device made up of a combination of electronic and electromechanical (i.e. electronic and mechanical) components. Computer has no intelligence by itself and is referred to as hardware.

A computer system is a combination of five elements:

Hardware

Software

People

Procedures

Data/information

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When one computer system is set up to communicate with another computer system, connectivity becomes the sixth system element. In other words, the manner in which the various individual systems are connected — for example, by phone lines, microwave transmission, or satellite — is an element of the total computer system.

Software is the term used to describe the instructions that tell the hardware how to perform a task. Without software instructions, the hardware doesn’t know what to do. People, however, are the most important component of the computer system: they create the computer software instructions and respond to the procedures that those instructions present.

The basic job of the computer is the processing of information. Computers accept information in the form of instructions called a program and characters called data to perform mathematical and logical operations, and then give the results. The data is raw material while information is organized, processed, refined and useful for decision making. Computer is used to convert data into information and to store information in the digital form.

Notes

Connectivity
- связь, согласованность; raw material(s) - сырье

Lesson 2. How computer works

  1. Read the title and guess the main idea of the text.

  2. Read the first sentence of every paragraph and guess the ideas it covers. Begin with the 3d one.

  3. Read and translate the whole text.

A computer is an electronic machine which can accept data in a certain form, process the data and give the results of the processing in a specified format as information.

First, data is fed into the computer’s memory. Then when the program is run, the computer performs a set of instructions and processes the data. Finally, we can see the results (the output) on the screen or in printed form.

A computer system consists of two parts: hardware and software. Hardware is any electronic or mechanical part you can see or touch.

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Software is a set of instructions, called a program, which tells the computer what to do.

A general purpose computer has four main sections: the arithmetic and logic unit (ALU), the control unit, the memory, and the input and output devices (collectively termed I/O). These parts are interconnected by busses, often made of groups of wires.

The control unit, ALU, registers, and basic I/0 (and often other hardware closely linked with these) are collectively known as a central processing unit (CPU).

CPU
is perhaps the most influential component. It has two functions: (1) it obtains instructions from the memory and interprets them and (2) it performs the actual operations. The first function is executed by the control unit which in its turn also performs two functions. It (1) interprets the instruction and, on the basis of this interpretation, (2) tells the ALU what to do next.

Early CPUs were composed of many separate components but since the mid-1970s CPUs have typically been constructed on a single integrated circuit called a microprocessor.

ALU. ALU performs the actual operations through the use of electronic signals. This unit is capable of performing automatically addition, subtraction, multiplication, division, comparing, selecting, and other mathematical and logical operations. What happens in the ALU while an instruction is being executed? In most computers only one word at a time can be transferred between the ALU and the memory. Hence, to perform an operation involving two arguments, the first argument must be transferred from the memory to the ALU and stored there temporally while the second argument is being transferred. The special memory cell in the ALU for this purpose is called the accumulator. The operation being performed, the result is formed in the accumulator before it is transmitted back to memory.

Control unit. The control unit (often called a control system or central controller) directs the various components of a computer. It reads and interprets (decodes) instructions in the program one by one. The control system decodes each instruction and turns it into a series of control signals that operate the other parts of the computer. Control systems in advanced computers may change the order of some instructions so as to improve performance. A key component common to all CPUs is the program counter, a special memory cell (a register) that keeps track of which location in memory the next instruction is to be read from. The control system’s function is as follows — (note that this

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is a simplified description, and some of these steps may be performed concurrently or in a different order depending on the type of CPU).

  1. To read the code for the next instruction from the cell indicated by the program counter.

  2. To decode the numerical code for the instruction into a set of commands or signals for each of the other systems.

  3. To increment the program counter so that it points to the next instruction.

  4. To read whatever data the instruction requires from cells in memory (or perhaps from an input device). The location of this required data is typically stored within the instruction code.

  5. To provide the necessary data to an ALU or register. If the instruction requires an ALU or specialized hardware to complete, instruct the hardware to perform the requested operation.

  6. To write the result from the ALU back to a memory location or to a register or perhaps an output device.

Since the program counter is (conceptually) just another set of memory cells, it can be changed by calculations done in the ALU. Adding 100 to the program counter would cause the next instruction to be read from a place 100 locations further down the program. Instructions that modify the program counter are often known as “jumps” and allow for loops (instructions that are repeated by the computer) and often conditional instruction execution (both examples of control flow).

It is noticeable that the sequence of operations that the control unit goes through to process an instruction is in itself like a short computer program — and indeed, in some more complex CPU designs, there is another yet smaller computer called a micro sequencer that runs a microcode program that causes all of these events to happen.

Multitasking.
While a computer may be viewed as running one gigantic program stored in its main memory, in some systems it is necessary to run several programs simultaneously. This is achieved by having the computer switch rapidly between running each program in turn. One means by which this is done is with a special signal called an interrupt which can periodically cause the computer to stop executing instructions where it was and do something else instead. By remembering where it was executing prior to the interrupt, the computer can return to that task later. If several programs are running “at the same time”, then the interrupt generator might cause several hundred interrupts per second, switching a program each time. Since modern computers typically execute instructions several orders of magnitude

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faster than human perception, it may appear that many programs are running at the same time even though only one is executing in any given instant. This method of multitasking is sometimes termed “time-sharing” since each program is allocated a “slice” of time in turn. Before the era of cheap computers, the principle use for multitasking was to allow many people to share the same computer. Seemingly, multitasking would cause a computer that is switching between several programs to run more slowly — in direct proportion to the number of programs it is running. However, most programs spend much of their time waiting for slow input/output devices to complete their tasks. If a program is waiting for the user to click on the mouse or press a key on the keyboard, then it will not take a “time slice” until the event it is waiting for has occurred. This frees up time for other programs to execute so that many programs may be run at the same time without unacceptable speed loss.

Multiprocessing.
Some computers may divide their work between one or more separate CPUs, creating a multiprocessing configuration. Traditionally, this technique was utilized only in large and powerful computers such as supercomputers, mainframe computers and servers. However, multiprocessor and multi-core (multiple CPUs on a single integrated circuit) personal and laptop computers have become widely available and are seeing increased usage in lower-end markets as a result.

Supercomputers in particular often have unique architectures that differ significantly from the basic stored-program architecture and from general purpose computers. They often feature thousands of CPUs, customized high-speed interconnects, and specialized computing hardware. Such designs tend to be useful only for specialized tasks due to the large scale of program organization required to successfully utilize most of the available resources at once. Supercomputers usually see usage in large-scale simulation, graphics rendering, and cryptography applications, as well as with other so-called “embarrassingly parallel” tasks.

Networking and the Internet. Computers have been used to coordinate information between multiple locations since the 1950s. The U.S. military’s SAGE (Semi Automatic Ground Environment) system was the first large-scale example of such a system, which led to a number of special-purpose commercial systems like Sabre. In the 1970s, computer engineers at research institutions throughout the United States began to link their computers together using telecommunications technology. This effort was funded by DARPA (now ARPA), and the

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IV. Match these terms (1-10) with the correct meaning (A-J).

computer network that it produced was called the ARPANET. The technologies that made the Arpanet possible spread and evolved. In time, the network spread beyond academic and military institutions and became known as the Internet. The emergence of networking involved a redefinition of the nature and boundaries of the computer. Computer operating systems and applications were modified to include the ability to define and access the resources of other computers on the network, such as peripheral devices, stored information, and the like, as extensions of the resources of an individual computer. Initially these facilities were available primarily to people working in high-tech environments, but in the 1990s the spread of applications like e-mail and the World Wide Web, combined with the development of cheap, fast networking technologies like Ethernet and ADSL saw computer networking become almost ubiquitous. In fact, the number of computers that are networked is growing phenomenally. A very large proportion of personal computers regularly connect to the Internet to communicate and receive information. “Wireless” networking, often utilizing mobile phone networks, has meant networking is becoming increasingly ubiquitous even in mobile computing environments.

Notes

RAM
- оперативное запоминающее устройство; ROM - постоянное запоминающее устройство; BIOS (Basic Input/Output System) - базовое устройство ввода/вывода; to orchestrate - организовывать, контролировать; a cache memory - сверхоперативное запоминающее устройство; a lower-end market - нижний эшелон рынка; DARPA (Defense Advanced Research Projects Agency) - Управление перспективных исследовательских программ; ARPANET (Advanced Research Project Agency Network) - сеть с коммутацией пакетов; явилась прообразом сети Интернет; ADSL (Asymmetrical Digital Subscribers Line) - асимметричная цифровая абонентская линия.
1 software

A component that coordinates all the other parts of the computer system

2 peripherals

B the brain of the computer

3 main memory

C physical parts that make up a computer system

4 hard drive (also known as hard disk)

D programs which can be used on a particular computer system

5 hardware

E the information which is presented to the computer

6 input

F results produced by a computer

7 ports

G input devices attached to the CPU
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