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Output devices display or store information generated by the CPU. Whereas input devices have the job of converting data from the real world into a form the computer can use, output devices …
Text 10. Storing Data: Secondary Memory Devices
When you turn off the computer, the contents of RAM are erased. Any information – term papers, documents, or programs – is deleted when the power to the computer is interrupted. In order to maintain data and information permanently, a computer system must have access to secondary or auxiliary memory. Today’s computer systems use a variety of secondary memory devices for storing data, including floppy disks, hard disks, CD-ROM, interactive video disk (IVD), and magnetic tape.
The most popular type of electronic data storage in a computer system is magnetic disk storage, commonly referred to as floppy disks, hard disks, and storage tape. A magnetic disk is a direct access storage device (DASD) that permits the computer to find data directly on the disk. Magnetic disks allow any portion of the disk to be accessed immediately, in any order. This differs from magnetic tape storage. With magnetic tape storage, data must be accessed sequentially; that is, a computer must begin reading from the beginning of the tape and proceed until it locates the desired data. Therefore, to access the last sequential record (data) on a tape, the computer must first read all prior records.
The surface of a magnetic disk is divided into concentric circles called tracks. It is further divided into sections that resemble pieces of a pie called sectors. Data are stored on the intersection of tracks and sectors in locations called cells. Each cell is defined by an address that allows direct access. By giving the disk drive an address, it is possible for the disk drive to move directly to a cell and either read or write data. The same amount of data is stored on each track and cell, whether it is an inner or outer circle.
The disk drive is the device that reads and writes to and from magnetic disks. Disk drives contain an access arm equipped with read-write heads that travel over the surface of the disk to locate specific cell addressed. The read-write head either reads (i.e., obtains data from the disk and transfers data to the CPU) or writes (i.e., transfers data from the CPU to the disk). Reading makes a copy without altering the original data. Writing replaces, actually writes over, the original data in a process that is similar to recording a new song over an old one on a cassette tape.
Typical computers use magnetic disk and disk drives as the chief secondary storage devices.
Floppy Disks and Floppy Disk Drives
Floppy disks, also called diskettes, are magnetic storage media that can be removed from the computer and transported to another computer. They are called floppy disks because the magnetic surface is very thin and flexible inside the protective case.
Portability is the most significant aspect of a floppy disk. You can save information from one computer on a floppy disk and then use that disk on another computer. In most cases, people use floppy disks to save information they create so their data can be safely stored or used at other computer locations.
Floppy disk drives come in several sizes and storage capacities.
Hard Disks and Hard Disk Drives
Most minicomputer systems also use hard disks as a means of storing data. Hard disk drives typically contain a magnetic disk and the read/write heads in a single sealed unit. In other words, hard disk drives are not transportable; they are fully self-contained.
The advantage of hard disks is that they provide greater storage capacity (up to several gigabytes of data) than floppy disks and operate at a much higher retrieval speed. They are popular because they permit users to access files directly from their computers rather than from disks they have to insert and remove. Typically, hard disks are used to store programs, operating systems, and the data required to turn on and use a computer.
It would be very difficult to operate a computer system with a hard disk alone. There must be a method for transporting data into the computer and then transferring data to the hard disk. This process is the role of the floppy disk. In many cases, the software you purchase comes on floppy disks but requires installation onto your hard disk. This usually means you insert the floppy in its drive and then execute an installation or setup procedure that copies all the data from the original diskettes.
An important relationship between hard disks and floppy disks also occurs in the process of backing up (making a duplicate) data. Because hard disks malfunction, or crash, it is important to have a copy of all your data on floppy disks. To avoid the loss of data, users periodically back up (copy) data from their hard disks to floppy disks, which can be stored outside the system.
Hard disks operate much faster than floppy disks, in large part because hard disks are sealed and are free from contamination.
Optical Storage Devices
Today, there is a new type of storage device based on the presence or absence of light, that is, optical storage. These devices use optical disks onto which a laser has encoded binary data. Once an optical disk is enclosed, the optical disk drive uses another laser to read the encoded data.
One advantage of an optical storage device is that it can retain a great deal of information in a very small area. Several billion bits of data or information can fit on one optical disk. Another advantage is that stored data is actually burned into the disk, making it far more stable than magnetically stored data. Currently, most computer optical storage devices only read data. New types of optical disks, some combining optical and magnetic technology, allow both reading and writing of data, but these haven’t yet replaced magnetic disks as the primary storage devices. Magnetic disk technology is still faster than optical disks for storing and transferring data.
CD-ROM (compact disk – read only memory) technology is the basis for multimedia. By allowing large amounts of data, including audio, text, computer data, and video to be stored on a single source, CD-ROM has made multisensory software possible. There are many fine examples of software that have been developed as a direct result of CD-ROM technology. You can get an entire encyclopedia of text, pictures, sounds, and short video segments on a single CD-ROM. A computer game enthusiast will acknowledge that the exceptionally high-quality sound and images of CD-ROM have made today’s computer games technological wonders. There are also electronic books that allow you to access material directly and permit linkage to other sections of books. The advantages to a student are that you get all of the text and pictures presented in an order that you control. You may stop anywhere and view related photos, click on a word to branch to a glossary, use an electronic notebook to keep your notes on a disk, even view a historical timeline. It may not be too long before you carry a couple of CD-ROMs to a university instead of a bag full of books.
Lexical Exercises
I. Find the translation of the following words in the vocabulary, transcribe them, read aloud and remember.
| · direct-access storage device (DASD) |
| · track |
| · sector |
| · compact disk – read only memory (CD-ROM) |
| · erase |
| · multimedia |
| · backup |
II. Check your comprehension. Which variant is correct according to the text?
1. What is the most common computer storage device?
a) an optical disk drive
b) a mouse
c) a magnetic disk
d) an electronic book
2. Magnetic tape storage accesses data in _________ order.
a) sequential
b) bi-directional
c) random
d) multimodel
3. What provides the foundation of multimedia?
a) hand disk drives
b) speakers
c) sound cards
d) CD-ROMs
4. The advantage of hard disks is that they provide
a) quick access to data
b) great storage capacity
c) saving of information
d) recording of information
III. Answer the questions.
1. What happens with the contents of RAM when the computer is turned off?
2. What are the most popular types of electronic data storage in a computer?
3. Where are data stored?
4. What is the disk drive?
5. What is the diskette?
6. Why are hard disks popular?
7. What are the advantages of an optical storage device?
8. What does “CD-ROM” stand for?
9. What examples of software developed as the result of CD-ROM technology are described in the text?
Grammar Focus
IV. Write what you would say in these situations using reported speech.
Example: George says: “I’m tired”. Three minutes later he says: “Let’s go for a walk”. What would you say? You said you were tired.
1. Ann says: “I’m working on my computer program tomorrow evening”. Later that day she says: “Let’s go out tomorrow evening!” What would you say?
2. Tom said: “I don’t play computer games”. A few days later you see him playing a computer game. What would you say?
3. Jack said: “I can’t come to the university today”. An hour later you meet him in the classroom. What would you say?
4. You arranged to meet Mary. She said: “I won’t be late”. She arrives 30 minutes late. What would you say?
5. Your friend says: “I am busy.” A minute later he invites you to a party. What would you say?
6. Sue tells you: “Sam has gone away”. Later that day you meet him. What would you say?
Speaking
V. Give a summary of the text.
VI. Complete the following sentences. Add more information about secondary memory devices.
1. The most popular type of electronic data storage in a computer system is magnetic disk storage, commonly referred to as hard disks, …
2. Floppy disks, also called diskettes, are magnetic storage media that can be …
Text 11. Other Input/Output Devices
Ports
Flexibility is a key to any computer. Users may need to add a variety of devices to expand their computer systems. All expansion devices (peripherals) connect to the CPU through ports. Ports enable cables to connect peripheral devices to the CPU.
Serial ports are used for cables that transmit bits one at a time. They are frequently used for connecting modems or special input devices such as a mouse, light pen, graphics tablet, or joystick.
Parallel ports are used for cables that transmit several bits of data simultaneously, such as an entire eight-bit character. Most printers use parallel ports. although some printers do use a serial port.
Special ports include connection to networks and to peripherals such as keyboards, monitors, external disk drives, and scanners. These ports may work in either serial or parallel fashion depending on the device for which they have been designed.
Expansion Slots
In most cases, ports connect directly to the motherboard. This design allows peripheral connection to use a standard plug-in design. For example, there is a standard serial plug, parallel plug, keyboard plug, and so forth. However, some devices do not connect to the CPU directly through the motherboard. These devices require the addition of an interface card to link them to the CPU. Interface cards fit into expansion slots on the motherboard inside the computer case. For example, in many computer systems the video card is plugged into a slot that serves as the interface (link) between the monitor and the CPU.
Depending on the type of computer, there can be several different types of expansion slots. In most cases, slots are designated according to the system bus. Within the MS-DOS/Intel family, there are several different slot configurations. Personal computers can use industry standard architecture (ISA), extended industry standard architecture (EISA), video electronic standard (VESA), micro channel, and peripheral connect interface (PCI). The more bits and the greater the megahertz, the faster the interface.
Personal computer memory card international association (PCMCIA) is another type of expansion slot. PCMCIA slots were originally designed for notebook computers. Notebook computers do not have room for the rather large interface cards often associated with desktop computers, and PCMCIA provides a small slot directly connected to the motherboard. The interface card connected to these slots functions as part of the device rather than as a separate card. In many cases PCMCIA devices are the size of a credit card and contain all of the functions of much larger devices. For example, PCMCIA modems and hard disk drives are very small and plug directly into the PCMCIA slot. An additional advantage of PCMCIA is that these devices can be inserted and removed without interrupting power to the computer. This enables users to switch between devices without having to terminate a computer session.
SCSI Ports
A small computer system interface (SCSI) is another type of port added to a computer system through an expansion slot. SCSI cards allow multiply devices to connect into one port through chaining (one device connected to another). For example, with one SCSI port you can connect a hard disk. To that hard disk you can connect a CD-ROM. To that CD-ROM you can connect a scanner.
MIDI
Musical instrument digital interface (MIDI) is popular for connecting musical devices, such as electronic keyboards, to a computer system. In many cases MIDI either comes with or is directly associated with the installation of a sound card. With MIDI you can connect a musical instrument, and you can also have access to a series of MIDI files to generate a variety of musical sounds (commonly called voices). For example, an electronic piano keyboard may link to a computer through a MIDI port. You can then use MIDI files to make the piano keyboard sound like a harpsichord, organ, and choir. In fact, there are thousands of voices available through MIDI. However, MIDI is not used for human speech.
Lexical Exercises
I. Find the translation of the following words in the vocabulary, transcribe them, read aloud and remember.
| · serial ports | · bus |
| · parallel ports | · design |
| · expansion slot | · plug |
| · insert | · installation |
II. Check your comprehension. Which variant is correct according to the text?
1. Special ports may work in ____________ fashion.
a) serial
b) parallel
c) either serial or parallel
d) both serial and parallel
2. The interface card connected to PCMCIA slots functions as
a) a separate card
b) part of the device
c) a program
d) output device
3. You can connect ________________ with one SCSI port.
a) a hard disk
b) a CD-ROM
c) a scanner
d) through chaining a hard disk, a CD-ROM and a scanner
4. MIDI is used for
a) generating musical sounds
b) typing
c) human speech
d) connecting musical devices
III. Answer the questions.
1. Why is flexibility a key to any computer?
2. What types of ports are described in the text? What are they used for?
3. Is a standard plug-in design the only way to connect to the CPU?
4. Do notebook computers have room for the rather large interface cards?
5. What is an additional advantage of PCMCIA?
6. What is a SCSI added to a microcomputer system through?
7. What device can make the piano keyboard sound like an organ?
Grammar Focus
IV. Translate the following sentences paying attention to the sequence of tenses.
1. I didn’t know that you were interested in programming so much.
2. She said she would come to the seminar in time.
3. The professor told the students that those computers had been used only for specific purposes.
4. He said they were not used at industrial enterprises any more.
5. Everybody knew that Jim spent all his spare time in the Internet.
6. All the students believed that Peter spoke very good German.
7. I remembered very well that she had lived in the house next to the post-office.
8. He asked me if I knew anything about that transaction.
9. We didn’t know whether our ideas would be accepted by the developers of the programs.
Speaking
V. Give a summary of the text.
VI. Complete the following sentences. Add more information about interfacing input/output devices.
1. Devices (peripherals) are connected to the CPU through …
2. A number of different types of ports are available on computer systems, including …
3. However, some devices do not connect to the CPU directly through the motherboard. These devices require…
4. Depending on the type of computer, there can be several different types of…
5. Notebook computers do not have room for the rather large…
Section II
Text 1. Types of Manufacturing Automation
There are three types of manufacturing automation: fixed automation, programmable automation and flexible automation. Fixed automation or “hard” automation is an automated production equipment in which the order of processing operations is fixed by the facility form. That is, the programmed commands are contained in the machines in the form of different mechanisms that is not easily changed over from one product type to another. It is therefore suitable for products that are made in large quantities.
An automated production line is an example of fixed automation, since these lines are typically set up for long production runs, perhaps making millions of product units and running for several years between changeovers. Modern automated lines are controlled by programmable logic controllers, which are special computers that facilitate connections with industrial equipment.
Programmable automation is often used for producing products in batches. For each new batch the production equipment must be reprogrammed and changed over to accommodate the new product style. This reprogramming and changeover takes time to accomplish, and there is a period of nonproductive time followed by a production run for each new batch.
Numerical control is a form of programmable automation in which a machine is controlled by numbers (and other symbols) that have been coded on punched paper tape or an alternative storage medium. Since this form of numerical control is made by computer, it is called computer numerical control, or CNC.
Flexible automation is a kind of programmable automation. The disadvantage with programmable automation is the time required to program and change over the production equipment for each batch of new product. In flexible automation, the variety of products is sufficiently limited so that the changeover of the equipment can be done very quickly and automatically. The reprogramming of the equipment in flexible automation is done off-line; that is, the programming is made at a computer terminal without using the production equipment.
A flexible manufacturing system (FMS) is a form of flexible automation in which several machine tools are linked together by a material-handling system, and all aspects of the system are controlled by a central computer. An FMS is distinguished from an automated production line by its ability to process more than one product style simultaneously. At any moment, each machine in the system may be processing a different product.
Lexical Exercises
I. Find the translation of the following words in the vocabulary, transcribe them, read aloud and remember.
| · fixed automation | · accommodate |
| · flexible automation | · numerical |
| · programmable automation | · punched paper |
| · facility | · material-handling system |
| · facilitate | · batch |
II. Pay attention to the following groups of words with the same root. Define their part of speech and translate them into Russian.
program, programmable, programming, to program, programmed
facility, facilitate, facilitation, facilitator
number, numerical, numeric, numerically
product, produce, production, productive, productivity, producing
require, requirement, required,
III. Find these misleading words in the article and give their correct translation.
| · machine | · processing |
| · run | · medium |
| · process | · control |
IV. Match the English verbs given below with their Russian equivalents.
| 1. contain | 1. соединять |
| 2. control | 2. производить |
| 3. process | 3. управлять |
| 4. facilitate | 4. содержать |
| 5. accommodate | 5. облегчать |
| 6. run | 6. приноравливаться, подходить |
| 7. require | 7. требовать |
| 8. link | 8. работать, выполнять |
| 9. produce | 9. различать |
| 10.distinguish | 10. обрабатывать |
V. Answer the following questions.
1. Why is “hard” automation called “fixed”?
2. Is automated production line an example of flexible automation?
3. Which type of automation is used for producing products in batches?
4. What controls a machine in programmable automation?
5. What’s the difference between programmable and flexible automation?
6. What is a material handling system?
Grammar Focus
VI. State the forms and functions of the infinitive and translate the sentences into Russian.
1. To remove the oxygen and useless materials, the iron ore along with coke and limestone are charged into the blast furnace.
2. Bessemer was the first to develop the process for making inexpensive steel.
3. The use of preheated air and gas makes it possible to obtain much higher temperatures in the future.
4. Bessemer’s idea was to use an egg-shaped container.
5. To write the program the programmer must have a good understanding of the problem for the computer.
6. To make possible communication from a human being and a computer is the main purpose of the input unit.
7. The machine to be made at our plant will differ from the previous one.
8. The students come to the laboratory to make experiments.
9. To understand metallurgy, knowledge of chemistry and physics is required.
10. To completely identify a DOS file, you must include its name and path to the root directory.
11. These computers may not be on the same networks and require a variety of passwords and protocols to communicate.
12. Writing a computer program involves analysis of the problem to be solved and an algorithm to solve it.
Speaking
VII. Ask as many questions as you can about the text.
VIII. Give a summary of the text.
Text 2. Computer Process Control
In computer process control, a digital computer directs the operations of a manufacturing process. Other automated systems are typically controlled by computer too, but it is the term “computer process control” that is generally associated with continuous production operations involving such materials as, for example, chemicals and some basic metals. In these operations the products are typically processed in gas, liquid, or powder form to facilitate flow of the material through the various steps of the production cycle. It should be taken into account that these products are usually mass-produced. Because of the ease of handling the product and the large volumes involved, a high level of automation has been accomplished in these industries. The modern computer process control system generally includes the following: (1) measurement of important process variables such as temperature, flow rate, and pressure, (2) execution of some optimizing strategy, (3) actuation of such devices as valves, switches, and furnaces that enable the process to implement the optimal strategy, and (4) generation of reports to management indicating equipment status, production performance, and product quality. Today computer process control is applied to many industrial operations. The typical modern process plant is computer-controlled. In such a plant that produces more than 20 products, the facility is divided into three areas. Each area has its own process-control computer to perform scanning, control, and alarm functions. The computers are connected to a central computer in a hierarchical configuration. The central computer calculates how to obtain maximum yield from each process and generates management reports on process performance. Each process computer monitors up to 2,000 parameters that are required to control the process, such as temperature, flow rate, pressure, liquid level, and chemical concentration. These measurements are taken on a sampling basis; the time between samples varies between 2 and 120 seconds, depending on the relative need for the data. Each computer controls approximately 400 feedback control loops. Under normal operation, each control computer maintains operation of its process at or near optimum performance levels. If process parameters exceed the specified normal or safe ranges, the control computer actuates a signal light and alarm horn and prints a message indicating the nature of the problem for the technician. The central computer receives data from the process computers and performs calculations to optimize the performance of each processing unit. The results of these calculations are then passed to the individual process computers in the form of changes in the set points for the various control loops. Substantial economic advantages are obtained from this type of computer control in the process industries. The computer hierarchy is capable of integrating all the data from the many individual control loops far better than humans are able to do, thus permitting a higher level of performance. Advanced control algorithms can be applied by the computer to optimize the process. In addition, the computer is capable of sensing process conditions that indicate unsafe or abnormal operation much more quickly than humans can. All these improvements increase productivity, efficiency, and safety during process operation.
Lexical Exercises
I. Find the translation of the following words in the vocabulary, transcribe them, read aloud and remember.
| · liquid | · enable |
| · powder | · implement |
| · flow | · generation |
| · production cycle | · performance |
| · accomplish | · apply |
| · variable | · yield (n.) |
| · involve | · sample |
| · include | · feedback |
| · rate | · loop |
| · pressure | · exceed |
| · execution | · range |
| · valve | · actuate |
| · switch | · set point |
| · furnace | · sense (v.) |
II. Pay attention to the following groups of words with the same root. Define their part of speech and translate them into Russian.
vary, various, variable, variety, variant, varying, variance
press, pressure, pressed, presser, pressing, pressurized
apply, applied, application, appliance
execution, execute, executor, executive, executory
generate, generation, general, generally
III. Find these misleading words in the article and give their correct translation.
| · execution | · enable |
| · generation | · range |
| · performance | · actuate |
IV. Look through the columns of words and find the words which have the same meaning.
| 1. involve | 1. pattern |
| 2. rate | 2. cycle |
| 3. execute | 3. include |
| 4. enable | 4. outcome |
| 5. implement | 5. given parameters |
| 6. yield | 6. perform |
| 7. sample | 7. feel |
| 8. loop | 8. use |
| 9. actuate | 9. empower |
| 10. set point | 10. carry out |
| 11. sense | 11. activate |
| 12. apply | 12. speed |
V. Tick (ü) 5 statements which are expressed in the text.
a. The term “computer process control” is only associated with continuous production operations.
b. In continuous production operations products are generally mass-produced.
c. Measurement of process variables, performing the best strategy, actuation of different devices and generation of report management are main steps of an operator’s daily work.
d. Today computer process control is applied to many industrial operations.
e. The computers are connected to a central computer in a certain way.
f. The operator generates management reports on process performance.
g. Each control computer maintains operation of its process at or near optimum performance levels.
Grammar Focus
VI. Translate the sentences paying attention to the Objective Infinitive Construction.
1. They consider the methods of purifying materials to have undergone great changes in recent years.
2. He didn’t hear anybody enter the laboratory.
3. The scientist supposed the presence of the second element to change the stable form of a solid metal.
4. The teacher wanted his students to type the text as quickly as possible.
5. I know him to be the best programmer in this team.
6. We consider Norbert Wiener to be the father of Cybernetics.
7. The customers expected the company to provide them with technical support.
8. Due to the fast development of IT technology we expect this type of dual system to be in place within just a few years.
Speaking
VII. Read the sentence and complete it logically. Add some more information to develop your idea.
Today computer process control is applied …..
VIII. Give a summary of the text.
Text 3. Computer Control in Metals Industries
Like all the other processing industries, the basic metals industries (iron and steel, aluminum, etc.) have automated many of their processes by computer control. The metals industries deal in large volumes of products, and so there is a substantial economic motive to invest in automation. However, metals are typically produced in batches rather than continuously, and it is generally more difficult to handle metals in bulk form than, for instance, chemicals that flow. An example of computer process control in the metals industry is the rolling of hot metal ingots into final shapes such as coils and strips. This was first done in the steel industry, but similar processing is also accomplished with aluminum and other metals. In a modern steel plant, hot-rolling is performed under computer control. The rolling process involves the forming of a large, hot metal billet by passing it through a rolling mill consisting of one or more sets of large cylindrical rolls that squeeze the metal and reduce its cross section. Several passes are required to reduce the ingot gradually to the desired thickness. Sensors and automatic instruments measure the dimensions and temperature of the ingot after each pass through the rolls, and the control computer calculates and regulates the roll settings for the next pass. In a large plant, several orders for rolled products with different specifications may be in the mill at any given time. Control programs have been developed to schedule the sequence and rate at which the hot metal ingots are fed through the rolling mills. The production control task of scheduling and keeping track of the different orders requires rapid, massive data gathering and analysis. In modern plants this task has been effectively integrated with the computer control of the rolling mill operations to achieve a highly automated production system.
There are several approaches to computer control in metallurgy nowadays. One of them is development of mathematical models of certain manufacturing processes. A classical algorithm of optimal control is made on the basis of mathematical formulation and process control parameters.
Unfortunately, this model is not ideal. It isn’t able to give the exact mathematical formulation of the process and consider all factors known to a man, who still remains the main figure in the control system of a certain metallurgical process. In this connection, practical knowledge of experienced operators seems to be very useful. This knowledge is formalized and realized in appropriate programs for electronic computer.
Such an approach to the construction of process control algorithms is called Expert Control Systems. In the last decade Expert Control Systems have been developed in the field of artificial intelligence and are being intensively used in the metals industries today.
Lexical Exercises
I. Find the translation of the following words in the vocabulary, transcribe them, read aloud and remember.
| · handle | · strip |
| · deal in | · billet |
| · roll | · pass (n.) |
| · rolling mill | · schedule (v.) |
| · roll setting | · sequence |
| · rolling | · keep track |
| · final shapes | · mathematical formulation |
| · coil | · realize |
| · ingot | · squeeze |
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