Учебно-методическое пособие infotech hardware москва 2009




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RAM is an acronym for random access memory, a type of computer memory that can be accessed randomly; that is, any byte of memory can be accessed without touching the preceding bytes. RAM is the most common type of memory found in computers and other devices, such as printers.

There are two basic types of RAM: dynamic RAM (DRAM) and static RAM (SRAM).

The two types differ in the technology they use to hold data, dynamic RAM being the more common type. Dynamic RAM needs to be refreshed thousands of times per second. Static RAM does not need to be refreshed, which makes it faster; but it is also more expensive than dynamic RAM. Both types of RAM are volatile, meaning that they lose their contents when the power is turned off. In common usage, the term RAM is synonymous with main memory, the memory available to programs.

In contrast, ROM (read-only memory) refers to special memory used to store programs that boot the computer and perform diagnostics. Most personal computers have a small amount of ROM (a few thousand bytes). In fact, both types of memory (ROM and RAM) allow random access. To be precise, therefore, RAM should be referred to as read/write RAM and ROM as read-only RAM. ROM is referred to as being nonvolatile.



PROM (programmable read-only memory): A PROM is a memory chip on which you can store a program. But once the PROM has been used, you cannot wipe it clean and use it to store something else. Like ROMs, PROMs are non-volatile. PROMs are manufactured as blank chips on which data can be written with a special device called a PROM programmer.

EPROM (erasable programmable read-only memory): An EPROM is a special type of PROM that can be erased by exposing it to ultraviolet light.

EEPROM (electrically erasable programmable read-only memory): An EEPROM is a special type of PROM that can be erased by exposing it to an electrical charge.

Flash memory is a special type of EEPROM that can be erased and reprogrammed in blocks instead of one byte at a time. Flash memory is non-volatile, which means that it does not need power to maintain the information stored in the chip. In addition, flash memory offers fast read access times and better kinetic shock resistance than hard disks. These characteristics explain the popularity of flash memory for applications such as storage on battery-powered devices. Another allure of flash memory is that when packaged in a "memory card", it is enormously durable, being able to withstand intense pressure, extremes of temperature and immersion in water.

Many modern PCs have their BIOS stored on a flash memory chip so that it can easily be updated if necessary. Such a BIOS is sometimes called a flash BIOS. Flash memory is also popular in modems because it enables the modem manufacturer to support new protocols as they become standardized.



Firmware is programming that is inserted into programmable read-only memory, thus becoming a permanent part of a computing device. Firmware is created and tested like software. When ready, it can be distributed like other software and, using a special user interface, installed in the programmable read-only memory by the user. Firmware is sometimes distributed for printers, modems, and other computer devices.

Cache is a special high-speed storage mechanism. It can be either a reserved section of main memory or an independent high-speed storage device. Two types of caching are commonly used in personal computers: memory caching and disk caching.

A memory cache, sometimes called a cache store or RAM cache, is a portion of memory made of high-speed static RAM (SRAM) instead of the slower and cheaper dynamic RAM (DRAM) used for main memory. Memory caching is effective because most programs access the same data or instructions over and over. By keeping as much of this information as possible in SRAM, the computer avoids accessing the slower DRAM.

Some memory caches are built into the architecture of microprocessors. Such internal caches are often called Level 1 (L1) caches. Most modern PCs also come with external cache memory, called Level 2 (L2) caches. These caches sit between the CPU and the DRAM. Like L1 caches, L2 caches are composed of SRAM but they are much larger.

Some microprocessors have two levels of cache built right into the chip. In this case, the motherboard cache -- the cache that exists between the microprocessor and main system memory -- becomes level 3, or L3 cache.

Disk caching works under the same principle as memory caching, but instead of using high-speed SRAM, a disk cache uses conventional main memory. The most recently accessed data from the disk is stored in a memory buffer. When a program needs to access data from the disk, it first checks the disk cache to see if the data is there. Disk caching can dramatically improve the performance of applications, because accessing a byte of data in RAM can be thousands of times faster than accessing a byte on a hard disk.

When data is found in the cache, it is called a cache hit, if not, it is called a cache miss and the computer must wait for a round trip from the larger, slower memory area. The effectiveness of a cache is judged by its hit rate. Many cache systems use a technique known as smart caching, in which the system can recognize certain types of frequently used data. The strategies for determining which information should be kept in the cache constitute some of the more interesting problems in computer science.

There are a lot of subsystems in a computer; you can put cache between many of them to improve performance. Here's an example. We have the microprocessor (the fastest thing in the computer). Then there's the L1 cache that caches the L2 cache that caches the main memory which can be used (and is often used) as a cache for even slower peripherals like hard disks and CD-ROMs. The hard disks are also used to cache an even slower medium -- your Internet connection.

Virtual memory is an imaginary memory area supported by some operating systems in conjunction with the hardware. You can think of virtual memory as an alternate set of memory addresses. Programs use these virtual addresses rather than real addresses to store instructions and data. When the program is actually executed, the virtual addresses are converted into real memory addresses.

Often, that amount of RAM is not enough to run all of the programs that most users expect to run at once. With virtual memory, the computer can look for areas of RAM that have not been used recently and copy them onto the hard disk. This frees up space in RAM to load the new application. Because it does this automatically, you don't even know it is happening, and it makes your computer feel like is has unlimited RAM space even though it has only 32 megabytes installed. Because hard-disk space is so much cheaper than RAM chips, virtual memory also provides a nice economic benefit.

The area of the hard disk that stores the RAM image is called a page file. It holds pages of RAM on the hard disk, and the operating system moves data back and forth between the page file and RAM. (On a Windows machine, page files have a .SWP extension.)

Of course, the read/write speed of a hard drive is much slower than RAM, and the technology of a hard drive is not geared toward accessing small pieces of data at a time. If your system has to rely too heavily on virtual memory, you will notice a significant performance drop. The key is to have enough RAM to handle everything you tend to work on simultaneously. Then, the only time you "feel" the slowness of virtual memory is in the slight pause that occurs when you change tasks. When you have enough RAM for your needs, virtual memory works beautifully. When you don't, the operating system has to constantly swap information back and forth between RAM and the hard disk. This is called thrashing, and it can make your computer feel incredibly slow.


Vocabulary
constantly непрерывно, непрестанно, бесконечно, все время, постоянно

load загрузка, загрузить например, программу в ОЗУ, данные в регистр; вставить, поместить например, дискету в дисковод

POST внутренний начальный тест, самотестирование при включении питания

boot sequence последовательность начальной загрузки

boot загрузка, начальная загрузка (системы), самозагрузка

загружать; выполнять начальную загрузку

maintain поддерживать, обслуживать

maintenance поддержка, эксплуатация, техническое обслуживание

functionality функциональность, набор функциональных возможностей

enriched functionality

high functionality расширенные функциональные возможности

operational functionality эксплуатационные возможности

multifunction многофункциональный

conserve сохранять, сберегать

purge удалять (ненужную информацию)

Syn: delete, erase, remove

random случайный; произвольный; нерегулярный

randomly случайно, наугад, произвольно

preceding предшествующий

refresh регенерировать, обновлять, восстанавливать

volatile непостоянный, временный (об информации, записываемой в память, но не сохраняемой при завершении приложения)

энергозависимый, не сохраняющий информацию при выключении (электро-)питания (о ЗУ)

nonvolatile энергонезависимый

ROM постоянное запоминающее устройство, ПЗУ

RAM оперативная память, оперативное запоминающе

устройство, ОЗУ

PROM (Programmable Read-Only Memory) программируемое постоянное запоминающее устройство, ППЗУ; вид памяти, в которую запись может быть произведена только один раз с помощью специального устройства, программатора

EPROM (Erasable [Electrically] Programmable Read-Only Memory) стираемое программируемое постоянное запоминающее устройство, СППЗУ, перепрограммируемая память тип микросхем перепрограммируемой постоянной памяти с ультрафиолетовым стиранием

EEPROM = E2PROM (Electrically [Electrical] Erasable Programmable Read-Only Memory) электрически стираемое программируемое постоянное запоминающее устройство, ЭСППЗУ, электрически стираемая память

be exposed to подвергаться воздействию; Syn: be subjected to

be unaffected to не подвергаться воздействию

resistant устойчивый, невосприимчивый

firmware встроенное ПО, записанное в ППЗУ/ПЗУ ПО

insert вставка, вставить

install устанавливать, инсталлировать

avoid избегать, аннулировать, отменять, делать недействительным

compose формировать; компоновать

cache hit удачное [результативное] обращение в кэш

cache miss неудачное обращение к кэшу, отсутствие нужных данных

hit rate частота успешных обращений (к кэш-памяти), коэффициент совпадений (попаданий) данных

virtual memory виртуальная память способ расширения объёма адресуемой физической памяти за счет разбиения её на страницы ( page) фиксированного размера и организации выгрузки неиспользуемых страниц в буферную область на диске и загрузки их с диска при запросе

conjunction связывание, соединение

performance drop падение производительности

handle обрабатывать; оперировать, манипулировать

swap переставлять, менять местами; подкачивать

swap file файл подкачки

swapping подкачка, свопинг в системах с виртуальной памятью - передача сегмента или страницы данных/программы с диска в ОЗУ ( swapping in) или в обратном направлении ( swapping out)

thrashing пробуксовка в системах с виртуальной памятью - снижение эффективности процессора из-за чрезмерно большого количества запросов на подкачку страниц

shock resistance ударопрочность

withstand, withstood устоять, выдержать; противостоять; не поддаваться

withstand overload выдерживать перегрузки

withstand pressure выдерживать давление

extreme экстремальное значение, экстремальный

immersion погружение





  1. Answer the following questions:

What is binary notation?

What does ROM, ROM stand for?

Why do both types of RAM refer to volatile memory?

What is the main difference between DRAM and SRAM?

What is the main function of ROM?

What are the benefits of flash memory?

What makes memory caching be very effective?

What is smart caching?

When does a performance drop occur?

What is thrashing?


  1. Find in the text the equivalents to the following words and phrases :

хранить данные

включать компьютер

выключать компьютер

загружать данные

выполнять начальную загрузку

стирать под воздействием ультрафиолета

встраивать в архитектуру микропроцессора




  1. Define the following terms: BIOS, POST, ROM, RAM, cache, virtual memory.




  1. Fill in the gaps with following terms: CPU, RAM, ROM, virtual memory, POST.

  1. Some computers also use.…, which expands physical memory onto a hard disk.

  2. The computer loads data from ….. and performs …. to make sure all the major components are functioning properly.

  3. The computer loads the basic input/output system (BIOS) from …..

  4. The computer loads the operating system (OS) from the hard drive into the system's …..

  5. Generally, the critical parts of the operating system are maintained in …. as long as the computer is on. This allows the …. to have immediate access to the operating system, which enhances the performance and functionality of the overall system.

  6. When you open an application, it is loaded into …. When you save a file and close the application, the file is written to the specified storage device, and then it and the application are purged from …..




  1. The verb refer has different meanings. Construct your own sentences with the verb refer.




  • If you refer to a particular subject or person, you talk about them or mention them.

In his speech, he referred to a recent trip to Canada.

  • If a word refers to a particular thing, situation, or idea, it describes it in some way.

The term electronics refers to electrically-induced action.

  • If you refer to a book or other source of information, you look at it in order to find something out.

He referred briefly to his notebook.

  • If you refer someone to a source of information, you tell them the place where they will find the information which they need or which you think will interest them.

Mr Bryan also referred me to a book by the American journalist Anthony Scaduto.


  1. Translate the text.




  1. Translate the following sentences.




  1. Виpтуальная память - использование жесткого диска как pасшиpение опеpативной памяти для повышения ее объема.

  2. Виртуальная Память создается из-за недостатка Оперативной Памяти.

  3. ЭСППЗУ может меняться путем стирания электрическим способом.

  4. ЭСППЗУ обеспечивает энергонезависимую память.

  5. Компьютеры, содержащие микросхемы ЭСППЗУ, имеют специальное аппаратное обеспечение для стирания и перезаписи ЭСППЗУ.

  6. Кэш позволяет ускорить обращение процессора к ОЗУ за счет предварительной записи временно хранимых данных.

  7. Обращения в кэш улучшают производительность компьютера, т.к. ЦП может получить быстрый доступ к данным кэш.

  8. БИОС отвечает за тестирование и начальную загрузку системы.

  9. ПЗУ представляет собой полупроводниковую память, из которой можно читать, но в которую нельзя записывать.

  10. ОЗУ представляет собой рабочую память компьютера и определяет размер и число программ, которые могут выполняться одновременно, а также количество данных, которые могут быть немедленно обработаны.

  11. ROM BIOS является наиболее общим примеров встроенного ПО.

  12. В отличие от ОЗУ, постоянная память остается неизменной при отключении электропитания.


Section 3

Input Devices
Input device refers to any device that transfers data, programs, or signals into a processor system. Such devices provide the human-computer interface, the keyboard being the most common example. Current devices include pointing devices, data collection terminals, speech recognition units, magnetic card readers, and image capturing devices.

Pointing device is a generic term for any device (e.g., a graphics tablet, mouse, stylus, pointing stick, or trackball) used to control the movement of a cursor on a computer screen.

Data collection terminal refers to a terminal at which a person can enter data into a computer-based system or receive data from one.
Input (n) the process of entering data into a processing system, or the data that is entered

Input (v) enter data
Unit 1

Computer Keyboards
A keyboard's primary function is to act as an input device. Using a keyboard, a person can type a document, use keystroke shortcuts, access menus, play games and perform a variety of other tasks. Keyboards can have different keys depending on the manufacturer, the operating system they're designed for, and whether they are attached to a desktop computer or part of a laptop. But for the most part, these keys, also called keycaps, are the same size and shape from keyboard to keyboard. They're also placed at a similar distance from one another in a similar pattern, no matter what language or alphabet the keys represent.

Most keyboards have between 80 and 110 keys, including:



  • Typing keys

  • A numeric keypad

  • Function keys

  • Control keys

The typing keys include the letters of the alphabet, generally laid out in the same pattern used for typewriters. This layout is known as QWERTY for its first six letters.

Keyboards can also use a variety of other typing key arrangements. The most widely known is Dvorak, named for its creator, August Dvorak. The Dvorak layout places all of the vowels on the left side of the keyboard and the most common consonants on the right. The most commonly used letters are all found along the home row. The home row is the main row where you place your fingers when you begin typing. People who prefer the Dvorak layout say it increases their typing speed and reduces fatigue. Other layouts include ABCDE, XPeRT, QWERTZ and AZERTY. Each is named for the first keys in the pattern. The QWERTZ and AZERTY arrangements are commonly used in Europe.

The numeric keypad is a more recent addition to the computer keyboard. As the use of computers in business environments increased, so did the need for speedy data entry. Since a large part of the data was numbers, a set of 17 keys, arranged in the same configuration found on adding machines and calculators, was added to the keyboard.

In 1986, IBM further extended the basic keyboard with the addition of function and control keys. Applications and operating systems can assign specific commands to the function keys. Control keys provide cursor and screen control. Four arrow keys arranged in an inverted T formation between the typing keys and numeric keypad move the cursor on the screen in small increments.

Other common control keys include:



  • Home

  • End

  • Insert

  • Delete

  • Page Up

  • Page Down

  • Control (Ctrl)

  • Alternate (Alt)

  • Escape (Esc)

The Windows keyboard adds some extra control keys: two Windows or Start keys, and an Application key. Apple keyboards, on the other hand, have Command (also known as "Apple") keys. A keyboard developed for Linux users features Linux-specific hot keys, including one marked with "Tux" the penguin -- the Linux logo/mascot.

A keyboard is a lot like a miniature computer. It has its own processor and circuitry that carries information to and from that processor. A large part of this circuitry makes up the key matrix.

The key matrix is a grid of circuits underneath the keys. When you press a key, it presses a switch, completing the circuit and allowing a tiny amount of current to flow through. The mechanical action of the switch causes some vibration, called bounce, which the processor filters out. If you press and hold a key, the processor recognizes it as the equivalent of pressing a key repeatedly.

As you type, the processor in the keyboard analyzes the key matrix and determines what characters to send to the computer. It maintains these characters in its memory buffer and then sends the data.

Many keyboards connect to the computer through a cable with a PS/2 or USB (Universal Serial Bus) connector. Laptops use internal connectors. Regardless of which type of connector is used, the cable must carry power to the keyboard, and it must carry signals from the keyboard back to the computer.

Wireless keyboards, on the other hand, connect to the computer through infrared (IR), radio frequency (RF) or Bluetooth connections. IR and RF connections are similar to what you'd find in a remote control. Regardless of which sort of signal they use, wireless keyboards require a receiver, either built in or plugged in to the USB port, to communicate with the computer. Since they don't have a physical connection to the computer, wireless keyboards have an AC power connection or use batteries for power.

Whether it's through a cable or wireless, the signal from the keyboard is monitored by the computer's keyboard controller. This is an integrated circuit (IC) that processes all of the data that comes from the keyboard and forwards it to the operating system. When the operating system (OS) is notified that there is data from the keyboard, it checks to see if the keyboard data is a system level command. A good example of this is Ctrl-Alt-Delete on a Windows computer, which reboots the system. Then, the OS passes the keyboard data on to the current application.

The application determines whether the keyboard data is a command, like Alt-f, which opens the File menu in a Windows application. If the data is not a command, the application accepts it as content, which can be anything from typing a document to entering a URL to performing a calculation. If the current application does not accept keyboard data, it simply ignores the information. This whole process, from pressing the key to entering content into an application, happens almost instantaneously.



Vocabulary

keystroke нажатие клавиши

keyboard shortcut клавишная комбинация быстрого вызова

keycap таст, клавишевый колпачок

numeric keypad цифровая клавиатура

function keys функциональные клавиши

control keys клавиши управления

layout схема размещения

vowel гласный звук

consonant согласный звук

fatigue усталость, утомление

feel fatigue чувствовать усталость

increment увеличение, приращение, инкремент

mascot талисман; эмблема на передней части капота

key matrix клавиатурная матрица

grid сетка; решётка

completed circuit замкнутая цепь; установленное соединение

current электрический ток; текущий, данный

bounce возврат, отскок

ac (power )supply питание от сети переменного тока

alternating current ( AC, a.c.) переменный ток

direct current ( DC) постоянный ток





  1. Answer the following questions:

What types of keyboards do you know?

What is a layout?

What is the advantage of Dvorak layout?

How does the keyboard operate?

List all types of the keys.




  1. Describe wireless keyboards. Use the following verbs:

встраивать add-in , built-in, embed

подключать attach, plug, plug in connect, hook,

включать switch on, turn on

выключать key off, key out, switch off, turn off, uncouple

переключать change over, switch, key




  1. Find in the text the equivalents to the following words and phrases :

подсоединять к компьютеру

схема размещения клавиш

условия бизнеса, бизнес-среда, деловая среда

обеспечивать дополнительные возможности базовой клавиатуры

часть схемы составляет клавиатурная матриц

замыкать схему

обрабатывать данные




  1. Fill in the gaps with following terms: character, current, key, processor, data matrix, bounce, circuitry, computer, switch.



  1. A keyboard is a lot like a miniature ... . It has its own processor and … that carries information to and from that processor. A large part of this circuitry makes up the… .

  2. The … is a grid of circuits underneath the…. When you press a key, it presses a …, completing the circuit and allowing a tiny amount of …to flow through. The mechanical action of the … causes some vibration, called …, which the processor filters out. If you press and hold a key, the … recognizes it as the equivalent of pressing a key repeatedly.

  3. As you type, the … in the keyboard analyzes the key matrix and determines what … to send to the computer. It maintains these characters in its memory buffer and then sends the… .

  1. Make up a plan and retell the text.




  1. Render the text.

На выставке CES в Лас-Вегасе компания Asustek Computer представила целый ряд продуктов с миниатюрными экранами: клавиатуру со встроенными в нее компьютером и сенсорным экраном с диагональю 5 дюймов и новую версию ноутбука M50 с дополнительным сенсорным экраном, который имеет диагональ 4,3 дюйма и расположен непосредственно под клавиатурой на месте привычной сенсорной панели. Клавиатуру Eee Keyboard можно подключать к любому устройству отображения, начиная от монитора и заканчивая жидкокристаллическим телевизором или цифровым проектором. На случай, если большого экрана под рукой все же не окажется, клавиатура снабжена собственным экраном с диагональю 5 дюймов, который располагается в правой части устройства.

Согласно задумке разработчиков, любой внешний экран или проектор с помощью клавиатуры Eee Keyboard легко можно превратить в Internet-монитор. Таким образом, для того чтобы иметь возможность комфортного обращения к Internet фактически из любого помещения, пользователю достаточно носить с собой только клавиатуру массой всего 950 г.

Устройство, работающее под управлением операционной системы Windows XP Home, оборудовано процессором Intel Atom с тактовой частотой 1,6 МГц, оперативной памятью DDR2 DRAM емкостью 1 Гбайт и встроенным твердотельным накопителем объемом 16 или 32 Гбайт, предназначенным для хранения данных.

Разработчики оснастили клавиатуру целым рядом беспроводных интерфейсов, включая Wi-Fi 802.11b/g/n, Bluetooth 2.0 и Ultra Wideband HDMI (high definition multimedia interface), и широким набором портов, в том числе USB 2.0, VGA, HDMI, а также разъемами для подключения наушников и микрофона.
Extended Activities
1. Describe the main trends in the keyboard market.

Unit 2

Computer Mice
Mice first broke onto the public stage with the introduction of the Apple Macintosh in 1984, and since then they have helped to completely redefine the way we use computers.

Every day of your computing life, you reach out for your mouse whenever you want to move your cursor or activate something. Your mouse senses your motion and your clicks and sends them to the computer so it can respond appropriately.

Developed by Agilent Technologies and introduced to the world in late 1999, the optical mouse actually uses a tiny camera to take thousands of pictures every second.

Able to work on almost any surface without a mouse pad, most optical mice use a small, red light-emitting diode (LED) that bounces light off that surface onto a sensor. In addition to LEDs, a recent innovation are laser-based optical mice that detect more surface details compared to LED technology. This results in the ability to use a laser-based optical mouse on even more surfaces than an LED mouse.

Optical mice have several benefits over track-ball mice:


  • No moving parts means less wear and a lower chance of failure.

  • There's no way for dirt to get inside the mouse and interfere with the tracking sensors.

  • Increased tracking resolution means a smoother response.

  • They don't require a special surface, such as a mouse pad.

A number of factors affect the accuracy of an optical mouse. One of the most important aspects is resolution. The resolution is the number of pixels per inch that the optical sensor and focusing lens "see" when you move the mouse. Resolution is expressed as dots per inch (dpi). The higher the resolution, the more sensitive the mouse is and the less you need to move it to obtain a response.

Most mice have a resolution of 400 or 800 dpi. However, mice designed for playing electronic games can offer as much as 1600 dpi resolution. Some gaming mice also allow you to increase the dpi on the fly to make the mouse less sensitive in situations when you need to make smaller, slower movements.

Historically, corded mice have been more responsive than wireless mice. This fact is changing, however, with the advent of improvements in wireless technologies and optical sensors. Other factors that affect quality include:



  • Size of the optical sensor -- larger is generally better, assuming the other mouse components can handle the larger size. Sizes range from 16 x 16 pixels to 30 x 30 pixels.

  • Refresh rate -- it is how often the sensor samples images as you move the mouse. Faster is generally better, assuming the other mouse components can process them. Rates range from 1500 to 6000 samples per second.

  • Image processing rate -- is a combination of the size of the optical sensor and the refresh rate. Again, faster is better and rates range from 0.486 to 5.8 megapixels per second.

  • Maximum speed -- is the maximum speed that you can move the mouse and obtain accurate tracking. Faster is better and rates range from 16 to 40 inches per second.

Most wireless mice use radio frequency (RF) technology to communicate information to your computer. Being radio-based, RF devices require two main components: a transmitter and a receiver.

The transmitter is housed in the mouse. It sends an electromagnetic (radio) signal that encodes the information about the mouse's movements and the buttons you click.



  • The receiver, which is connected to your computer, accepts the signal, decodes it and passes it on to the mouse driver software and your computer's operating system.

  • The receiver can be a separate device that plugs into your computer, a special card that you place in an expansion slot, or a built-in component.

Unlike infrared technology, which is commonly used for short-range wireless communications such as television remote controls, RF devices do not need a clear line of sight between the transmitter (mouse) and receiver. Just like other types of devices that use radio waves to communicate, a wireless mouse signal can pass through barriers such as a desk or your monitor.

RF technology provides a number of additional benefits for wireless mice. These include:



  • RF transmitters require low power and can run on batteries

  • RF components are inexpensive

  • RF components are light weight

As with most mice on the market today, wireless mice use optical sensor technology rather than the earlier track-ball system. Optical technology improves accuracy and lets you use the wireless mouse on almost any surface -- an important feature when you're not tied to your computer by a cord.

In order for the transmitter in the mouse to communicate with its receiver, they must be paired. This means that both devices are operating at the same frequency on the same channel using a common identification code. A channel is simply a specific frequency and code. The purpose of pairing is to filter out interference from other sources and RF devices.

Pairing methods vary, depending on the mouse manufacturer. Some devices come pre-paired.



Vocabulary

light-emitting diode светодиод, светоизлучающий диод, СИД

wear износ

failure отказ, выход из строя, неисправность

resolution разрешение, разрешающая способность

refresh rate частота обновления (регенерации)

sample пример, образец; отсчет, выборка, замер

замерять, производить выборку

image processing обработка изображений

(RF) technology радиочастотная технология

transmitter отправитель, передатчик, трансмиттер

receiver приёмник, получатель, ресивер

line of sight прямая видимость, линия визирования, линия прямой видимости

accuracy точность погрешность, с которой выполняется измерение или вычисление

interference вмешательство, интерференция; взаимные помехи

tracking слежение (за действиями, процессами, данными) ; отслеживание





  1. Answer the following questions:

When did the first mouse make its appearance?

When was the optical mouse introduced?

What is the advantage of the laser-based optical mouse?

List the benefits of optical mice over track-ball mice.

What is resolution?

What affects the accuracy of an optical mouse?

Describe RF technology.

What does RF stand for?


  1. Find in the text the equivalents to the following words and phrases :

разрабатывать

внедрять


отражать свет от поверхности

износ и выход из строя

служить помехой

более восприимчивый

передавать информацию

передатчик вмонтирован в мышь

встроенный компонент


  1. Fill in the gaps with the following terms: resolution, tracking, accuracy, sensor, rate:




  1. LED bounces light off that surface onto a … .

  2. Increased tracking … means a smoother response.

  3. A number of factors affect the … of an optical mouse.

  4. The … is the number of pixels per inch that the optical sensor and focusing lens "see" when you move the mouse.

  5. Image processing … is a combination of the size of the optical … and the refresh … .

  6. Maximum speed is the maximum speed that you can move the mouse and obtain accurate… .




  1. Make up a plan and retell the text.




  1. Render the following text.

Компания Logitech представила компьютерные мыши, которые значительно расширяют возможности их использования. Благодаря технологии Logitech Darkfield Laser Tracking с мышью можно работать практически на любой поверхности, включая стекло и глянцевые покрытия. Данная технология используется в моделях Logitech Performance Mouse MX и Logitech Anywhere Mouse MX, что позволяет выбрать для себя оптимальный вариант - полноразмерную мышь или компактную мышь для ноутбука.

Исследования Logitech показали, что у 40 % пользователей дома имеется какая-либо стеклянная поверхность. В сочетании с ростом популярности ноутбуков это значит, что люди перемещаются по дому и сталкиваются с самыми разными типами поверхностей (например, гранит или лакированное дерево), представляющими для обычных мышей и их систем слежения определенную проблему.

Обычные технологии лазерного слежения основаны на способности датчика мыши отслеживать свойства текстуры поверхности. Чем неоднороднее поверхность, тем проще датчику выявлять ориентиры, которые можно использовать для точного измерения движения. Тем не менее, такие глянцевые поверхности, как, например, стекло, отличаются гладкостью и отсутствием деталей, которые позволили бы датчику обычной лазерной мыши нормально работать.

Для работы на стекле (не менее 4 мм в толщину) в технологии Logitech Darkfield используются методы, позволяющие выявлять микроскопические частицы и царапины на поверхности, что устраняет необходимость в отслеживании самой поверхности. Аналогично тому, как человеческий глаз воспринимает ясное ночное небо, датчик мыши «видит» чистые участки стекла как темный фон, на котором присутствуют яркие точки — пыль. При этом датчик воспринимает движение этих точек, отслеживая движения мыши.

Гибкая система зарядки полноразмерной мыши Logitech Performance Mouse MX позволяет подзаряжать мышь через компьютер или настенную розетку даже во время ее использования. Четыре настраиваемые боковых кнопки повышают эффективность работы, позволяя быстро вызывать самые необходимые функции, например, переключение приложений или масштабирование. Помимо этого, динамическая боковая прокрутка, впервые реализованная в мыши Logitech, упрощает навигацию в интернете.

Ожидается, что мышь Logitech Performance Mouse MX поступит в продажу в США и Европе по рекомендуемой розничной цене в 99,99 евро.

Extended Aсtivities


  1. Transform square into rectangle. What actions will you perform? Use the following verbs:

put, position the cursor наводить курсор

press нажимать

release отпускать

hold down удерживать

move двигать

stretch тянуть

grab захватывать

drag перетаскивать
Unit 3

Image capture
A digital camera takes photos electronically and converts them into digital data (binary codes made up of Is and Os). It doesn't use the film found in a normal camera; instead it has a special light-sensitive silicon chip.

Conventional cameras depend entirely on chemical and mechanical processes -- you don't even need electricity to operate them. All digital cameras have a built-in computer, and all of them record images electronically.

Photographs are stored in the camera's memory before being sent to the computer. Some cameras can be also connected to a printer or a TV set, to make viewing images easier.

Since film still provides better picture quality, digital cameras have not completely replaced conventional cameras. But, as digital imaging technology has improved, digital cameras have rapidly become more popular.

A camcorder, or digital video camera, records moving pictures and converts them into digital data that can be stored and edited by a computer with special video editing software.

Digital video cameras are used by home users to create their own movies, or by professionals in computer art and video conferencing.

They are also used to send live video images via the Internet. Then they are called Web cameras or webcams.

Scanners have become an important part of the home office over the last few years. Scanners are great for archiving old photographs in a digital format that will never fade, converting print documents into digital word processing files that can be edited and even compiling and organizing business cards. At their core, scanners haven't changed much over the years, but they've become much more refined devices, capable of crisp and accurate reproductions.

Scanner technology is everywhere and used in many ways:



  • Flatbed scanners, also called desktop scanners, are the most versatile and commonly used scanners. Flatbed and photo scanners used to be separate devices, with the latter being much smaller and offering higher resolution and color depth to handle photographs. However, specifications for flatbed scanners have increased while the cost has stayed the same, and most new photo scanners are simply high-resolution flatbeds.

  • Sheet-fed scanners are similar to flatbed scanners except the document is moved and the scan head is immobile. Sheet-fed scanners are small models that feed a document or photograph through the thin, compact body of the scanner to capture an image. These are less popular than they were a decade ago, but they're still around. Sheet-fed scanners are more portable, but they don't usually have the same resolution or versatility of the full-size flatbed scanners.

  • Handheld scanners use the same basic technology as a flatbed scanner, but rely on the user to move them instead of a motorized belt. This type of scanner typically does not provide good image quality. However, it can be useful for quickly capturing text.

  • Drum scanners are used by the publishing industry to capture incredibly detailed images.

  • Film scanners are specialized scanners that can accommodate strip film or slides. Generally, film scanners have very high optical resolution, such as 2,400dpi or greater.

  • Speaking of portability, pen scanners have become more prevalent in recent years. These scanners can either scan text one line at a time or, in some of the newer models, scan entire documents or images in a single pass. They're extremely easy to carry around, but you need a steady hand to capture an accurate image.

Scanners vary in resolution and sharpness. Most flatbed scanners have a true hardware resolution of at least 300x300 dots per inch (dpi).

Sharpness depends mainly on the quality of the optics used to make the lens and the brightness of the light source.

Another term used when talking about scanners is bit depth, also called color depth. This simply refers to the number of colors that the scanner is capable of reproducing. Each pixel requires 24 bits to create standard true color and virtually all scanners on the market support this. Many of them offer bit depths of 36 bits (12 bits per primary color). They still only output in 24-bit color, but perform internal processing to select the best possible choice out of the colors available in the increased palette. More sophisticated scanners have 14 bits per color, or 42-bit color depth. Extended color depth is generally more important for photographic scanning or graphic arts work. There are many opinions about whether there is a noticeable difference in quality between 24-, 30-, 36-, and 42-bit scanners.

Scanning the document is only one part of the process. For the scanned image to be useful, it must be transferred to your computer. The connections used by scanners:


  • Universal Serial Bus (USB) - USB scanners combine good speed, ease of use and affordability in a single package.

  • FireWire - Usually found on higher-end scanners, FireWire connections are faster than USB and SCSI. FireWire is ideal for scanning high-resolution images.

On your computer, you need software, called a driver, that knows how to communicate with the scanner. Most scanners speak a common language, TWAIN. The TWAIN driver acts as an interpreter between any application that supports the TWAIN standard and the scanner. This means that the application does not need to know the specific details of the scanner in order to access it directly. For example, you can choose to acquire an image from the scanner from within Adobe Photoshop because Photoshop supports the TWAIN standard.

In addition to the driver, most scanners come with other software. Typically, a scanning utility and some type of image editing application are included.

A lot of scanners include OCR software. OCR allows you to scan in words from a document and convert them into computer-based text. It uses an averaging process to determine what the shape of a character is and match it to the correct letter or number. OCR software is now readily available for many low cost scanners giving good recognition rates.

One thing to keep in mind with scanners is that creating high-resolution scans consumes a lot of resources, including hard drive space. If you're going to be scanning numerous full-size images, make sure you've got a computer with the power and the space to handle them.




Did You Know?

TWAIN is not an acronym. It actually comes from the phrase "Never the twain shall meet" because the driver is the go-between for the software and the scanner. Because computer people feel a need to make an acronym out of every term, TWAIN is known as Technology Without An Interesting Name!


Vocabulary
image capture ввод (захват) изображений

convert преобразовывать, конвертировать

video editing видеомонтаж

flatbed scanner планшетный сканер

sheet-fed scanner постраничный сканер

handheld scanner ручной сканер тип портативного сканера, перемещение которого над сканируемой областью производится пользователем

drum scanner барабанный сканер

sharpness резкость

bit depth битовая глубина


  1. Answer the following questions:

What does a digital camera do?

What does a camcorder do?

What are the main types of scanners?

How do the scanners vary?

What is TWAIN?

What is OCR software?


  1. Find in the text the equivalents to the following words and phrases :

преобразовывать в цифровые данные

изображение

редактирование видеоданных

универсальный

стационарный



с высоким разрешением

  1. Match the terms to the definitions:



Terms

Definitions

OCR

An external peripheral interface standard for communication between a computer and external peripherals over low-cost cable using serial transmission.

image capture

A process in which a machine scans, recognizes, and encodes information printer or typed.

Scanner

A high speed, general purpose serial bus supporting a chain of up to 63 devices. IT is also known as IEEE1393 and, on computers, produced by Sony as iLink.

USB

A device that can capture an image and convert it into a unique set of electrical signals.

Firewire

A standard for interfacing between a scanner or digital camera and a graphics program.

TWAIN

The process of obtaining a digital image from a vision sensor. The conversion process is often accompanied with image compression.

flatbed scanner

A device in which the sheet to be scanned is placed flat into the bed of the device.




  1. Make up a plan and retell the text.




  1. Translate the following text.




  1. Примером автоматизированного ввода информации  могут служить сканеры штрих-кодов и другие системы оптического распознавания символов. Одно из преимуществ устройств автоматизированного ввода данных состоит в том, что при их использовании исключаются некоторые ошибки, неизбежные при вводе информации с клавиатуры. Сканер штрих-кодов делает менее чем одну ошибку на 10000 операций, в то время как обученный наборщик ошибается один раз при вводе каждых 1000 строк.

  2. Основные виды автоматизированного ввода информации – системы распознавания магнитных знаков, системы оптического распознавания символов, системы ввода информации на базе светового пера, сканеры, системы распознавания речи, сенсорные датчики и устройства видеозахвата.
    Системы распознавания магнитных знаков (
    Magnetic Inc Character Recognition, MICR) используются в основном в банковской сфере. В нижней части обычного банковского чека находится код, нанесенный специальными магнитными чернилами. В коде содержится номер банка, номер расчетного счета и номер чека. Система считывает информацию, преобразовывает ее в цифровую форму и передает в банк для обработки.
    Системы оптического распознавания символов (
    Optical Character Recognition, OCR) преобразуют специальным образом нанесенную на носитель информацию в цифровую форму. Наиболее широко используемые устройства этого типа – сканеры штрих-кодов (bar-code scanners), которые применяются в кассовых терминалах магазинов. Эти системы используются также в больницах, библиотеках, на военных объектах, складах продукции и в компаниях по перевозке грузов.

  3. Сканеры (scanners) преобразуют в цифровую форму графическую информацию (рисунки, чертежи и пр.) и большие объемы текстовой информации.

  4. Системы распознавания речи (voice input devices) преобразуют в цифровую форму произносимые пользователем слова. Существует два режима работы подобных устройств. В режиме управления (command mode) вы произносите команды (такие как "открыть документ", "запустить программу" и т.д.), которые выполняются компьютером. В режиме диктовки (dictation mode) можно надиктовать компьютеру любой текст. К сожалению, точность распознавания речи таких систем оставляет желать лучшего. Человеческий голос имеет множество оттенков, на точность распознавания может повлиять интонация, громкость речь, окружающий шум, даже банальный насморк. Тем не менее, работа над совершенствованием этих устройств ввода информации продолжается и, несомненно, у них большое будущее.

  5. Сенсорные датчики (sensors) – это устройства для ввода в компьютер пространственной информации. Например, корпорация General Motors использует сенсоры в своих легковых автомобилях для передачи в бортовой компьютер машины данных об окружающем пространстве и маршруте. Сенсорные датчики также нашли применение в системах виртуальной реальности, игровых приставках и симуляторах.

  6. Устройства видеозахвата (video capture devices) представляют собой небольшие цифровые видеокамеры, соединенные с компьютером. Устройства видеозахвата применяются в основном в системах видеоконференций, которые получают все большее распространение.




  1. Render the following text.


Новый 3D-сканер, мгновенно создающий 3D-модели

Компания ZScanner показала на выставке SIGGRAPH новый трехмерный сканер ZScanner 700. Небольшое устройство помещается в руке и может создавать трехмерные модели в реальном времени.

Во время сканирования создаваемая модель сразу же отображается на экране, благодаря чему можно увидеть ее недостатки и повернуть реальный объект должным образом или же приблизить к требуемому месту сканер. При этом сканирование происходит в рамках одной сессии, без прерываний. Благодаря этому можно получать более точные модели, которые требуют значительно меньше времени на пост-обработку.



Данные, полученные в результате сканирования, автоматически сохраняются в виде файла .stl, который можно импортировать в пакет для 3D-моделирования или же вывести на печать.

ZScanner 700 может использоваться в самых разных областях, в том числе для создании дизайна упаковок; для ведения архивных описей; для создания 3D-моделей для анимации и игр на основе макетов; для исторических исследований памятников архитектуры и музейных экспонатов и т.д.



Extended Activities


    1. Describe your own scanner. Use the new terms from the text.

    2. What scanner is the ideal one for general-purpose use and for the enlarging and editing photographs. State your opinion.

    3. Can we perceive the difference between 36-bit and 42-bit scanners? State your opinion.


Section 4

Output devices
Output device refers to any device that converts the electrical signals representing information within a compter into a form that can exist outside the computer. Printers and visual displays are the most common types of output device for interfacing to people, but voice is becoming increasingly available. Sound card is a plug-in module that adds sound input and output capabilities to a computer.
output(n) the result of data processing activity when it is presented external to the system

output (v) produce a result or signal
Unit 1

Computer monitor
Often referred to as a display screen, a video display terminal (VDT), visual display unit (VDU) or the monitor is the component of your computer system that displays the messages and data being processed and utilized by the computer's CPU.

Most desktop displays use liquid crystal display (LCD) or cathode ray tube (CRT) technology, while nearly all portable computing devices such as laptops incorporate LCD technology. Because of their slimmer design and lower energy consumption, monitors using LCD technology (also called flat panel or flat screen displays) replaced CRT on most desktops.

Liquid crystal display technology works by blocking light. Specifically, an LCD is made of two pieces of polarized glass (also called substrate) that contain a liquid crystal material between them. A backlight creates light that passes through the first substrate. At the same time, electrical current cause the liquid crystal molecules to align to allow varying levels of light to pass through to the second substrate and create the colors and images that you see.

Most LCD displays use active matrix technology. It is called TFT LCD and stands for thin-film transistor liquid-crystal display.



Resolution refers to the number of individual dots of color, known as pixels, contained on a display. Resolution is expressed by identifying the number of pixels on the horizontal axis (rows) and the number on the vertical axis (columns), such as 800x600. Resolution is affected by a number of factors, including the size of the screen.

Unlike CRT monitors, LCD monitors display information well at only the resolution they are designed for, which is known as the native resolution. Digital displays address each individual pixel using a fixed matrix of horizontal and vertical dots. If you change the resolution settings, the LCD scales the image and the quality suffers. Native resolutions are typically:



  • 17 inch = 1024x768

  • 19 inch = 1280x1024

  • 20 inch = 1600x1200

Two measures describe the size of your display: the aspect ratio and the screen size. Historically, computer displays, like most televisions, have had an aspect ratio of 4:3. This means that the ratio of the width of the display screen to the height is 4 to 3.

For widescreen LCD monitors, the aspect ratio is 16:9 (or sometimes 16:10 or 15:9). Widescreen LCD displays are useful for viewing DVD movies in widescreen format, playing games and displaying multiple windows side by side. High definition television (HDTV) also uses a widescreen aspect ratio.

Screen sizes are normally measured in inches from one corner to the corner diagonally across from it. This diagonal measuring system actually came about because the early television manufacturers wanted to make the screen size of their TVs sound more impressive.

Interestingly, the way in which the screen size is measured for CRT and LCD monitors is different. For CRT monitors, screen size is measured diagonally from outside edges of the display casing. In other words, the exterior casing is included in the measurement.

For LCD monitors, screen size is measured diagonally from the inside of the beveled edge. The measurement does not include the casing as indicated in the image below.

Because of the differences in how CRT and LCD monitors are measured, a 17-inch LCD display is comparable to a 19-inch CRT display. For a more accurate representation of a CRT's size, find out its viewable screen size. This is the measurement of a CRT display without its outside casing.

Popular screen sizes are 15, 17, 19 and 21 inches. Notebook screen sizes are smaller, typically ranging from 12 to 17 inches. As technologies improve in both desktop and notebook displays, even larger screen sizes are becoming available. For professional applications, such as medical imaging or public information displays, some LCD monitors are 40 inches or larger.

Obviously, the size of the display directly affects resolution. The same pixel resolution is sharper on a smaller monitor and fuzzier on a larger monitor because the same number of pixels is spread out over a larger number of inches. An image on a 21-inch monitor with an 800x600 resolution will not appear nearly as sharp as it would on a 15-inch display at 800x600.

The combination of the display modes supported by your graphics adapter and the color capability of your monitor determine how many colors it displays. For example, a display that operates in SuperVGA (SVGA) mode can display up to 16,777,216 (usually rounded to 16.8 million) colors because it can process a 24-bit-long description of a pixel. The number of bits used to describe a pixel is known as its bit depth.

With a 24-bit bit depth, eight bits are dedicated to each of the three additive primary colors -- red, green and blue. This bit depth is also called true color because it can produce the 10,000,000 colors discernible to the human eye, while a 16-bit display is only capable of producing 65,536 colors. Displays jumped from 16-bit color to 24-bit color because working in eight-bit increments makes things a whole lot easier for developers and programmers.

Simply put, color bit depth refers to the number of bits used to describe the color of a single pixel. The bit depth determines the number of colors that can be displayed at one time.

To create a single colored pixel, an LCD display uses three subpixels with red, green and blue filters. Through the careful control and variation of the voltage applied, the intensity of each subpixel can range over 256 shades. Combining the subpixels produces a possible palette of 16.8 million colors (256 shades of red x 256 shades of green x 256 shades of blue).

When you look at an LCD monitor from an angle, the image can look dimmer or even disappear. Colors can also be misrepresented. To compensate for this problem, LCD monitor makers have designed wider viewing angles. (Do not confuse this with a widescreen display, which means the display is physically wider.) Manufacturers give a measure of viewing angle in degrees (a greater number of degrees is better). In general, look for between 120 and 170 degrees. Because manufacturers measure viewing angles differently, the best way to evaluate it is to test the display yourself. Check the angle from the top and bottom as well as the sides, bearing in mind how you will typically use the display.

Brightness or luminance is a measurement of the amount of light the LCD monitor produces. It is given in nits or one candelas per square meter (cd/m2). One nit is equal to on cd/m2. Typical brightness ratings range from 250 to 350 cd/m2 for monitors that perform general-purpose tasks. For displaying movies, a brighter luminance rating such as 500 cd/m2 is desirable.

The contrast ratio rates the degree of difference of an LCD monitor's ability to produce bright whites and the dark blacks. The figure is usually expressed as a ratio, for example, 500:1. Typically, contrast ratios range from 450:1 to 600:1, and they can be rated as high as 1000:1. Ratios more than 600:1, however, provide little improvement over lower ratios.

The contrast ratio indicates how fast the monitor's pixels can change colors. Faster is better because it reduces the ghosting effect when an image moves, leaving a faint trial in such applications as videos or games.

Adjustability. Unlike CRT monitors, LCD monitors have much more flexibility for positioning the screen the way you want it. LCD monitors can swivel, tilt up and down, and even rotate from landscape (with the horizontal plane longer than the vertical plane) to portrait mode (with the vertical plane longer than the horizontal plane). In addition, because they are lightweight and thin, most LCD monitors have built-in brackets for wall or arm mounting.

Displays with touch-screen technology let you input information or navigate applications by touching the surface of the display.



Vocabulary

substrate основа, подложка

backlight заднее освещение; подсветка

TFT LCD жидкокристаллический дисплей на тонкоплёночных транзисторах

pixel пиксел, минимальный элемент изображения

aspect ratio коэффициент пропорциональности, соотношение размеров [сторон]; формат экрана (изображения)

discernible видимый, различимый; видный, заметный

color bit depth битовая глубина (число битов, используемое для описания цвета каждого пиксела изображения)

viewing angle угол обзора

contrast ratio степень контрастности, контрастность

response time время отклика

adjustability регулируемость; возможность настройки, возможность точной настройки

bezel фальш-панель

ghosting появление ореола (на изображении)


Basic Terminology
Bezel - This is the metal or plastic frame surrounding the display screen. On LCD displays, the bezel is typically very narrow.

Ghosting - An effect of slower response times that cause blurring of images on an LCD monitor, it's also known as latency. The effect is caused by voltage temporarily leaking from energized elements to neighboring, non-energized elements on the display.

Native resolution - This actual measurement of an LCD display, in pixels, is given in horizontal by vertical order.

Response time - The speed at which the monitor's pixels can change colors is called response time. It is measured in milliseconds (ms).

Viewing angle - It's the degree of angle at which you can view the screen from the sides (horizontal angle) and top/bottom (vertical angle) and continue to see clearly defined images and accurate colors.


  1. Answer the following questions:

What is the LCD technology?

What measures describe the size of your display?

What is the differences in how CRT and LCD monitors are measured?

How does the size of the display affect resolution?

Explain the calculations made to obtain a palette of 16.8 million colors.

What is a color bit depth, viewing angle, brightness, and contrast ratio?


  1. Give the synonyms to the terms computer monitor and LCD.

  2. Find in the text the equivalents to the following words and phrases:

потребление энергии

заднее освещение; подсветка

(электрический) ток

параметры настройки

по диагонали



скос; скошенный край


  1. Define the following terms: resolution, aspect ratio, color bit depth, viewing angle, brightness or luminance, contrast ratio, ghosting.




  1. Fill in the gaps with following terms: bit, native resolution, pixel, resolution.



  1. …refers to the number of individual dots of color, known as pixels, contained on a display.

  2. LCD monitors display information well at only the resolution they are designed for, which is known as the … .

  3. Digital displays address each individual … using a fixed matrix of horizontal and vertical dots

  4. Color bit depth refers to the number of … used to describe the color of a single pixel.

  5. The contrast ratio indicates how fast the monitor's … can change colors.

  6. The speed at which the monitor's … can change colors is called response time.




  1. Make up a plan and retell the text.




  1. Translate the following sentences.




  1. Органический светодиод (OLED - organic light-emitting diode) перспективное устройство для плоских дисплеев. По сравнению с ЖК-дисплеями потребляет меньше электроэнергии, имеет меньшие габариты и вес, более широкий угол обзора, отсутствует необходимость в подсветке экрана.

  2. IMOD: плоский экран без подсветки. Компания Qualcomm объявила о завершении разработки новой технологии формирования изображения IMOD Display System, призванной, по мнению создателей, прийти на смену современным ЖК-экранам. В ее основе лежит идея формирования цветного изображения методом интерференции световых волн, точно так же, как это происходит в природе, например, в крыльях бабочки или в хвостовых перьях павлина.

  3. Согласно заявлению разработчиков, IMOD-экраны практически не требуют подсветки, максимально используя окружающий свет. Подсветка необходима только в условиях крайне низкой освещенности или полного отсутствия таковой.
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