Ex.1. Read the text.
Computer networks
Networks are two or more computers that are connected with one another for the purpose of communicating data electronically. Besides physically connecting computer and communication devices, a network system serves the important function of establishing a cohesive architecture that allows a variety of equipment types to transfer information in a near-seamless fashion. Two popular architectures are ISO Open Systems Interconnection (OSI) and IBM's Systems Network Architecture (SNA).
Two basic network types are local-area networks (LANs) and wide-area (or long-haul) networks. LANs connect computers and peripheral devices in a limited physical area, such as a business office, laboratory, or college campus, by means of permanent links (wires, cables, fibre optics) that transmit data rapidly. A typical LAN consists of two or more personal computers, printers, and high-capacity disk-storage devices called file servers, which enable each computer on the network to access a common set of files. LAN operating system software, which interprets input and instructs networked devices, allows users to communicate with each other; share the printers and storage equipment; and simultaneously access centrally located processors, data, or programs (instruction sets). LAN users may also access other LANs or tap into wide-area networks. LANs with similar architectures are linked by “bridges,” which act as transfer points. LANs with different architectures are linked by “gateways,” which convert data as it passes between systems.
A LAN, as shown in the figure, may be configured as (1) a bus, a main channel to which nodes or secondary channels are connected in a branching structure, (2) a ring, in which each computer is connected to two neighbouring computers to form a closed circuit, or (3) a star, in which each computer is linked directly to a central computer and only indirectly to one another. Each of these has advantages, though the bus configuration has become the most common.
Even if only two computers are connected, they must follow rules, or protocols, to communicate. For example, one might signal “ready to send” and wait for the other to signal “ready to receive.” When many computers share a network, the protocol might include a rule “talk only when it is your turn” or “do not talk when anyone else is talking.” Protocols must also be designed to handle network errors.
The most common LAN design since the mid-1970s has been the bus-connected Ethernet, originally developed at Xerox PARC. Every computer or other device on an Ethernet has a unique 48-bit address. Any computer that wants to transmit listens for a carrier signal that indicates that a transmission is under way. If it detects none, it starts transmitting, sending the address of the recipient at the start of its transmission. Every system on the network receives each message but ignores those not addressed to it. While a system is transmitting, it also listens, and if it detects a simultaneous transmission, it stops, waits for a random time, and retries. The random time delay before retrying reduces the probability that they will collide again. This scheme is known as carrier sense multiple access with collision detection (CSMA/CD). It works very well until a network is moderately heavily loaded, and then it degrades as collisions become more frequent.
The first Ethernet had a capacity of about 2 megabits per second, and today 10- and 100-megabit-per-second Ethernet is common, with gigabit-per-second Ethernet also in use. Ethernet transceivers (transmitter-receivers) for PCs are inexpensive and easily installed.
A recent standard for wireless Ethernet, known as WiFi, is becoming common for small office and home networks. Using frequencies from 2.4 to 5 gigahertz (GHz), such networks can transfer data at rates from 11 to 54 megabits per second. Early in 2002 another Ethernet-like standard was released. Known as HomePlug, the first version could transmit data at about 8 megabits per second through a building's existing electrical power infrastructure.
Wide-area networks connect computers and smaller networks to larger networks over greater geographic areas, including different continents. They may link the computers by means of cables, optical fibres, or satellites, but their users commonly access the networks via a modem (a device that allows computers to communicate over telephone lines). The largest wide-area network is the Internet, a collection of networks and gateways linking millions of computer users on every continent.
Wide area networks (WANs) span cities, countries, and the globe, generally using telephone lines and satellite links. The Internet connects multiple WANs; as its name suggests, it is a network of networks. Its success stems from early support by the U.S. Department of Defense, which developed its precursor, ARPANET, to let researchers communicate readily and share computer resources. Its success is also due to its flexible communication technique. The emergence of the Internet in the 1990s as not only a communication medium but also one of the principal focuses of computer use was one of the most significant developments in computing.
Vocabulary:
cohesive – образующий единое целое
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carrier signal – сигнал-переносчик, сигнал несущей частоты
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seamless – однородный
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random time – режим произвольного включения
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fashion – форма
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CSMA – многостанционный (сетевой) доступ с контролем несущей, МДКН
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ISO International Organization for
Standardization – Международная организация по стандартизации
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collision detection – обнаружение конфликтов (в сети)
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OSI – взаимодействие открытых систем
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transceiver – приёмопередатчик, трансивер
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SNA – архитектура сетевых систем
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frequency – частота
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LAN – локальная (вычислительная) сеть, ЛВС
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via – посредством чего-л., с помощью чего-л.
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long-haul network – сеть с протяжёнными линиями (связи);
глобальная сеть
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gateway – межсетевой переход, межсетевой интерфейс
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wide-area network – глобальная (вычислительная) сеть, региональная сеть, ГВС
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to span – охватывать, простираться, распространяться
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fibre optics – волоконно-оптичес-кий кабель
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to stem – являться результатом
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bus – канал (передачи информации)
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precursor – предшественник
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node – узел, точка присоединения к сети
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ARPANET Advanced Research Project Agency Network – сеть Управления перспективных исследовательских программ
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Ex.2. Read the following international words and translate them:
Function, architecture, type, system, business, laboratory, college, cable, file, processor, program, instruction, to form, central computer, configuration, protocol, signal, address, recipient, scheme, megabit, gigabit, gigahertz, second, standard, version, electrical, infrastructure, geographic, continents, modem, telephone lines, computer resources, technique.
Ex.3. Answer the questions:
1. What are networks?
2. What function does a network system serve?
3. What does LAN operating system software allow users to do?
4. How may a LAN be configured?
5. What does any computer that wants to transmit listen for?
6. What happens when a computer detects no transmission?
7. What is the largest wide-area network?
Ex.4. Agree or disagree. Correct the sentence if it is fault.
1. LANs with different architectures are linked by “bridges”.
2. The most common LAN configuration is the ring one.
3. Every system on the network receives each message but ignores those not addressed to it.
4. The first Ethernet had a capacity of about four megabits per second.
5. Ethernet transceivers for PCs are inexpensive and easily installed.
Ex.5. Put questions to the underlined words.
1. LANs connect computers and peripheral devices in a limited physical area by means of permanent links (wires, cables, fibre optics) that transmit data rapidly.
2. Even if only two computers are connected, they must follow rules, or protocols, to communicate.
3. Protocols must be designed to handle network errors.
4. The most common LAN design since the mid-1970s has been the bus-connected Ethernet, originally developed at Xerox PARC.
5. CSMA/CD works very well until a network is moderately heavily loaded.
6. Early in 2002 another Ethernet-like standard was released.
Ex.6. Fill the table with the proper form of the adjective.
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Comparative
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Superlative
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common
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frequent
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small
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large
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great
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significant
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Ex.7. Find examples of the sentences with modal verbs. Explain their meanings.
Ex.8. Topics for discussion.
1. LANs
2. WANs
Unit 14
Ex.1. Read the following international words and translate them.
Physical, component, program, instruction, detail, central, reality, processor.
Ex.2. Read the text and make its outline.
Software
The physical components of a computer (the hardware) are not useful by themselves. Before they can function as intended, computers need program to coordinate the activities of these physical components. In addition, they need programs designed to perform specific tasks, such as word processing, payroll calculations, budget analyses, data manipulations, or the presentation of the information to students. All such programs are known as software.
A program is a series of instructions that tells the computer what to do. When the computer actually follows the instructions, we say that it executes the program. Computers will do only what they are told; they cannot make inferences or reach decisions by themselves. Consequently, every detail must be provided, because with missing steps or details the program will fail to perform as desired.
Programs of all types share one common feature. They consist of a list of instructions that the central processor can recognize. In reality, we rarely write the instructions that the processor itself needs, rather we write instructions that are later translated into these by a special program called either a compiler, condenser, or an interpreter, depending on how it performs the translation. At the processor level, instructions are very primitive, consisting of short sequences of bits representing numbers, which makes them difficult to use. Fortunately, instructions have been developed that are more meaningful to people, such as PRINT or GOTO that have meanings similar to their English language counterparts. These are far easier to use and are called high – level. A whole set of instructions is called a language.
The words to the text:
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software
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–
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программное обеспечение;
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hardware
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–
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аппаратные средства;
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to intend
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–
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намереваться, предназначать;
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word processing
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–
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обработка текстов;
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payroll
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–
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платёжная ведомость;
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to execute
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–
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выполнять;
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inference
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–
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логический вывод;
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consequently
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–
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следовательно;
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compiler
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–
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компилятор;
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interpreter
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–
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интерпретатор;
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sequence
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–
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последовательность;
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meaningful
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–
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содержательный;
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counterpart
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–
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копия;
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to perform
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–
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выполнять, представлять.
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Ex.3. Make up sentences.
hardware/ Computers/ the/ need/ of/ coordinate/ the/ to/ programs;
is/ to/ a/ instructions/ A/ of/ that/ program/ series/ tells/ the/ what/ computer/ do;
by/ Computers/ make/ or/ themselves/ cannot/ decisions/ inferences/ reach;
instructions/ the/ Programs/ a/ of/ that/ of/ consist/ processor/ recognize/ can/ list/ central;
A/ language/ is/ of/ set/ called/ whole/ a/ instructions.
Ex.4. Choose the only suitable form.
The first calculating machine … in 1812.
invented;
was invented;
had been invented.
Huge amounts of information … in computers.
a) are stored;
b) store;
c) stores.
3. Dr. Smith said that the computer … the most far – reaching social consequences.
a) have;
b) would have;
c) will have.
4. Our factories … by computers today.
a) run;
b) are running;
c) are being run.
5. The mechanics of space flight … by the computer.
a) is simulated;
b) simulate;
c) simulates.
6. The most flexible means of communication between man and machine … by the graphic computer.
a) have offered;
b) has offered;
c) have been offered.
7. She said the graphic computer … her to cope with that problem.
a) has helped;
b) had helped;
c) helped.
Ex.5. Write as many different questions to these answers as possible.
A program is a series of instructions that tells the computer what to do.
Programs consist of a list of instructions that the central processor can recognize.
A whole set of instructions is called a language.
Computers need programs to coordinate the activities of the hardware.
Computers cannot make inferences or reach decisions by themselves.
Ex.6. Fill in the gaps with the words from the box.
fail processor inferences
consequently
instructions
missing program compiler interpreter
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Computers will do only what they are told; they cannot make ….. or reach decisions by themselves.
….. , every detail must be provided, because with …. steps or details the program will …. to perform as desired.
In reality, we rarely write the instructions that the ….. itself needs, rather we write ….. that are later translated into these by a special …. called either a …., condenser or an …. .
Ex.7. Complete these word combinations with verbs. They all appear in the text.
to ………… the activities;
to ………… program;
to ………… an instruction;
to ………… an inference;
to ………… one common feature;
to ………… of sort sequences.
Ex.8. Word families. Fill in the missing words.
verb
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person
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thing
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program
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1)
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2)
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3)
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interpreter
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4)
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5)
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6)
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instruction
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Ex.9. Translate the following sentences, paying attention to the meanings of the conjunctions “whenever”, “whatever”, “wherever”:
Whenever a programmer has to do something new which he had never had before, he will rapidly teach himself how to do it in the best way.
Whatever differences exist between computer languages, the basic principles are the same.
The IT engineers planned to follow their ideas wherever they went.
Whatever disputes arise between creators of computer games, they can always be settled.
Ex.10. Look through the text and find equivalents to the following terms.
работать согласно своему предназначению – ...;
координировать работу – ...;
расчёт платёжной ведомости – ...;
помешать желаемой работе – ...;
принимать решения – ...;
распознавать команды – ...;
материальные составляющие компьютера – ... .
Ex.11. Talking points.
The physical components of computer.
What is a computer program?
Unit 15
Ex.1. Read and translate the text.
Software engineering
Computer programs or the software are growing more and more complicated, requiring teams of programmers and years of effort to develop. As a consequence, a new subdiscipline, software engineering, has arisen. The development of a large piece of software is perceived as an engineering task to be approached with the same care as the construction of a skyscraper, for example, and with the same attention to cost, reliability, and maintainability of the final product. The software-engineering process in general consists of several phases: (1) identification and analysis of user requirements, (2) development of system specifications (both hardware and software), (3) software design (perhaps at several successively more detailed levels), (4) implementation (actual coding), (5) testing, and (6) maintenance.
Even with such an engineering discipline in place, the software-development process is expensive and time-consuming. Since the early 1980s, increasingly sophisticated tools have been built to aid the software developer and to automate as much as possible the development process. Such computer-aided software engineering (CASE) tools span a wide range of types, from those that carry out the task of routine coding when given an appropriately detailed design in some specification language to those that incorporate an expert system to enforce design rules and eliminate software defects prior to the coding phase.
As the size and complexity of software has grown, the concept of reuse has become increasingly important in software engineering, since it is clear that extensive new software cannot be created cheaply and rapidly without incorporating existing program modules (subroutines, or pieces of computer code). One of the attractive aspects of object-oriented programming is that code written in terms of objects is readily reused. As with other aspects of computer systems, reliability – is usually rather vaguely defined as the likelihood of a system to operate correctly over a reasonably long period of time is a key goal of the finished software product. Sophisticated techniques for testing software have therefore been designed. For example, a large software product might be deliberately "seeded" with artificial faults, or "bugs"; if they are all discovered through testing, there is a high probability that most actual faults likely to cause computational errors have been discovered as well. The need for better trained software engineers has led to the development of educational programs in which software engineering is either a specialization within computer science or a separate program. The recommendation that software engineers, like other engineers, be licensed or certified is gaining increasing support, as there is the momentum toward the accreditation of software engineering degree programs.
Ex.2. Translate these sentences into Russian paying attention to the function of the Infinitive.
1. Computer programs are growing more complicated, requiring teams of programmers and years of effort to develop.
2. The development of a large piece of software is perceived as an engineering task to be approached with the same care as the construction of a skyscraper.
3. Since the early 1980s, increasingly sophisticated tools have been built to aid the software developer and to automate as much as possible the development process.
4. As with other aspects of computer systems, reliability - usually rather vaguely defined as the likelihood of a system to operate correctly over a reasonably long period of time - is a key goal of the finished software product.
Ex.3. Read and translate these words from the text and the word combinations with them paying attention to word formation.
code – coding,
computer – computational,
use – user – reuse,
program – programmer – programming,
develop – development – developer,
engineer – engineering,
maintenance – maintainability.
Software engineering, software design, software-development process, software developer, computer-aided software engineering (CASE), software defects, computer code, software product, computational error, development of educational programs, actual coding, object-oriented programming, program module.
Ex.4. Say whether these sentences are true or false.
The software has grown more in recent years.
The construction of a skyscraper is a more difficult engineering task than software development.
Sophisticated tools must be built to automate the software development process.
Reliability of computer systems is a key goal of the finished software product.
Computational errors can be discovered through software testing.
The concept of reuse in software engineering is not very popular now.
New software can be created cheaply and rapidly.
Ex.5. Find in the text Participles formed from the verbs given below and translate them.
To require, to sophisticate, to complicate, to give, to write, to finish, to exist, to increase, to train.
Ex.6. Translate the following sentences paying attention to the words with prefix “-sub”.
As a consequence, a new subdiscipline, software engineering, has arisen.
It is clear that extensive new software cannot be created cheaply and rapidly without incorporating existing program modules (subroutines, or pieces of computer code).
Ex.7. Explain the use of Tenses and Voices in these sentences.
1. Since the early 1980s, increasingly sophisticated tools have been built to aid the software developer and to automate as much as possible the development process.
2. As the size and complexity of software has grown, the concept of reuse has become increasingly important in software engineering.
3. Sophisticated techniques for testing software have therefore been designed.
4. The need for better trained software engineers has led to the development of educational programs in which software engineering is either a specialization within computer science or a separate program.
Ex.8. Read the text again and answer the questions.
Why has software engineering arisen as a new subdiscipline?
What types of CASE tools are mentioned in the text?
What is the main advantage of object-oriented programming?
What are the capabilities of software testing techniques?
Ex.9. Write 5 or 6 sentences to express your ideas of.
the reasons why the need for better trained software engineers has arisen in recent years;
the software-engineering process phases and their basic characteristics.
Unit 16
Ex.1. Read and learn the following international words.
Computer, personal, processor, intensive, industry, interface, electronics, graphical, design, information, innovation, interest, agent, social.
Ex.2. Read and translate the text.
User interfaces
Cheaper and more powerful personal computers are making it possible to perform processor intensive tasks on the desktop. Break thoughts in techno-logy, such as speech recognition, are enabling new ways of interacting with computers. And the convergence of personal computers and consumer electronic devices is broadening the base of computer users and placing a new emphasis on ease of use. Together, these developments will drive the industry in the next few years to build the first completely new interfaces since SRI International and Xerox’s Paolo Alto Research Center did their pioneering research into graphical user interfaces (GUIs) in the 1970s.
True, it is unlikely that you’ll be ready to toss out the keyboard and the mouse any time soon. Indeed, a whole cottage industry inspired by the hyperlinked design of the World Wide Web has sprung up to improve today’s graphical user interface.
Companies are developing products that organize information graphically in more intuitive ways. XML-based formats enable users to view content, including local and network files, within a single browser interface. But it’s the more dramatic innovations such as speech recognition that are poised to shake up interface design.
Speech will become a major component of user interfaces, and applications will be completely redesigned to incorporate speech input. Palm- size and handled PCs, with their cramped keyboards and basic handwriting recognition, will benefit from speech technology.
Though speech recognition may never be a complete replacement for other input devices, future interfaces will offer a combination of input types, a concept known as multimodal input. A mouse is a very efficient device for desktop navigation, for example, but not for changing the style of a paragraph. Multimodal interfaces will involve more than just traditional input devices and speech recognition. Eventually, most PCs will also have handwriting recognition, text to speech (TTS) the ability to recognize faces and gestures, and even the ability to observe their surroundings. The amount of information both on the Internet and within intranets at the fingertips of computer users has been expanding rapidly. This information onslaught has led to an interest in intelligent agents, software assistants that perform tasks such as retrieving and delivering information and automating repetitive tasks. Agents will make computing significantly easier. They can be used as Web browsers, help- desks and shopping assistants. Combined with the ability to look and listen, intelligent agents will bring personal computers one step closer to behaving more like humans. Researchers have long noted that users have a tendency to treat their personal computers as though they were human. By making computers more “social”, they hope to also make them easier to use.
Ex.3. 1. Cover the right column and read the English words and word combinations. Translate them into Russian and check your translation.
2. Cover the left column and translate the Russian words back into English.
processor – intensive tasks
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задачи, требующие интенсивной работы процессора;
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to interact with smth.
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–
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взаимодействовать с ч.- л.;
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desktop
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–
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настольный компьютер, рабочий стол (на экране компьютера);
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convergence
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–
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сходство;
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consumer
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–
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потребитель;
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user interface
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–
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пользовательский интерфейс;
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palm- size
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–
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карманный;
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to redesign
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–
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переконструировать;
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recognition
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–
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узнавание, распознавание;
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to toss out
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–
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выбрасывать, избавляться от ч.-л.;
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multimodal
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–
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многомодальный;
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efficient
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–
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эффективный, действенный;
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cramped keyboards
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–
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(зд.) сжатая, уменьшенная клавиатура;
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to incorporate speech input
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–
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включать ввод речи;
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to involve
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–
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привлекать, вовлекать, касаться;
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amount
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–
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количество;
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to retrieve
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–
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извлекать (хранимую) информацию;
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to deliver information
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–
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поставлять информацию.
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Ex.4. Complete these adjectives with appropriate comparative and superlative forms.
Cheap, powerful, dramatic, traditional, significant, graphical, wide.
Ex.5. Say whether you agree or disagree to these statements. Give your reasoning. You’d better start your answer with the following phrases:
Personally I think that…; In my opinion…; From my point of view…; As far as I see …; I’m not really sure if I would agree on that…; I wouldn’t agree. I can’t accept that…; I’m with you on that. I take your/ this point…; That’s exactly my opinion…; Yes, I agree to a point…;
Fewer people are using computers because computer functions are becoming integrated into other electronic devices.
There have been no improvements in interface design since the development of the GUI.
Speech recognition is likely to completely replace other input devices.
Intelligent agents will make computers seem more like humans.
Ex.6. Pair work. Put these questions to your groupmate and then ask him /her to answer them.
What developments favour the development of completely new interfaces?
What has inspired a whole cottage industry to develop to improve today’s graphical user interface?
In what way have XML- based formats changed the user interface?
What development has led to an interest in intelligent agents?
Name ways in which intelligent agents can be used.
Ex.7. Match the term in column A with the definition in column B.
Column A
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Column B
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a. GUI
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a. Software assistant that performs tasks such as retrieving and delivering information and automating repetitive tasks
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b. Multimodal interface
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b. Text to speech
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c. TTS
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c. A system that allows a user to interact with a computer using a combination of inputs such as speech recognition, hand- writing recognition, text to speech, etc.
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d. Intelligent agent
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d. Graphical user interface
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Ex.8. Complete these word combinations with appropriate verbs from the text.
to … computing significantly easier,
to … one’s personal computer,
to … information,
to … faces and gestures,
to … the keyboard and the mouse.
Ex.9. Make up a plan covering the main ideas of the text.
Ex.10. Give a summary of the text according to your plan.
Unit 17
Ex.1. Read the text.
The Internet
The Internet has already entered our ordinary life. Everybody knows that the Internet is a global computer network, which embraces hundred of millions of users all over the world and helps us to communicate with each other.
The Internet emerged in the United States in the 1970s. At that time it was used only to read different texts. Then in the early 1990s, a way was made to see pictures and listen to a sound on the Internet. This breakthrough made the Internet to be most demanded means of communication, data saving and transporting.
It is clear that the accurate number of users can be counted fairly approximately, nobody knows exactly how many people use the Internet today, because there are hundred of millions of users and their number is growing.
Nowadays the most popular Internet service is e-mail. Most of the people use the network only for sending and receiving e-mail messages. They can do it either they are at home or in the internet clubs or at work.
Another common service of the Internet is the Internet Relay Chat, or Chat. Chat allows a group of people, using aliases, to send messages to one another immediately. While used by a variety of age groups, it is especially popular among young people. Once connected, the user is brought into contact with a large number of other users from all around the world.
The World Wide Web or the Web is the leading information retrieval service of the Internet. The Web gives users access to a vast array of documents that are connected to each other by means of hypertext or hypermedia links—i.e., hyperlinks, electronic connections that link related pieces of information in order to allow a user easy access to them. Hypertext allows the user to select a word from text and thereby access other documents that contain additional information pertaining to that word; hypermedia documents feature links to images, sounds, animations, and movies. The Web operates within the Internet's basic client-server format; servers are computer programs that store and transmit documents to other computers on the network when asked to, while clients are programs that request documents from a server as the user asks for them. Browser software allows users to view the retrieved documents.
A hypertext document with its corresponding text and hyperlinks is written in HyperText Markup Language (HTML) and is assigned an online address called a Uniform Resource Locator (URL).
Other popular services are available on the Internet too. It is reading news, available on some dedicated news servers, telnet, FTP servers, etc.
You can work through the Internet, gambling and playing. However, there are some problems. The most important problem is security. When you send an e-mail, your message can travel through many different networks and computers. The data is constantly being directed towards its destination by special computers called routers. Because of this, it is possible to get into any of the computers along the rout, intercept and even change the data being sent over the Internet. But there are many encoding programs available. Notwithstanding, these programs are not perfect and can easily be cracked.
Another big and serious problem of the net is control. There is no effective control in the Internet, because of a huge amount of information circula- ting through the net. It is like a tremendous library and market together. In future, the situation might change, but now we have what we have.
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