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I. Match words from the text with their definitions.

Поиск

1. Removable A. Something that can be put or placed in

(something else).

2. Consumption B. Directed towards or concerning a particular

person or group.

3. Applicable C. The act of consuming.

4. Insertable D. Been able to be pulled or taken away.

5. Extractable E. Able to be taken away (from a place) taken

to another place.

 

II. Identify whether the following statements are true or false. Use the model:

Student A: The semiconductor memory card is used as a recording medium. – Student B: Yes, it is true.

S. A: SD cards are built-in. – S. B: No, it is false. These cards are hot-swappable, allowing the user to easily insert and remove them.

 

A memory card is one of internal storage media of a personal computer and multifunction terminal electronic equipment.

A flash memory is a type of EPROM that can be erased and reprogrammed in blocks instead of one byte at a time.

A flash memory is a semiconductor memory maintaining stored information even when power is off.

Flash memory devices require regular refreshing.

Flash memory cards are designed only in one standard.

USB connector is constructed that the flash memory card is insertable and extractable to a mounting wiring board through the slot port.

 

III. Complete the following sentences using words and expressions given below.

Flash memory devices have achieved a commercial success in an electronic industry because they are … to store data for a relatively long time.

Traditional film cameras have been widely … by digital cameras capable of recording images that may be downloaded to and stored on personal computers.

A semiconductor memory card has an internalized non-volatile memory, which is accessed by a connected device, enabling the semiconductor memory card to be used as a recording ….

Many digital cameras are also capable of … short video clips in standard digital video formats.

The pictures recorded by digital cameras can easily be … to common graphics file formats.

SD cards are hot-swappable, allowing the user to easily insert and remove SD cards without … power.

 

cycling able medium converted replaced capturing

 

IV. Answer the following questions.

1. What is one of external storage media of a personal computer?

2. What enables the semiconductor memory card to be used as a recording medium?

3. What type of memory is flash memory?

4. What advantages do flash memory devices have comparing with other memory devices?

5. What conveniences does flash memory bring to information industries?

6. What standards of flash memory cards design are available?

7. What is a USB connector?

 

Read the text.

The flash memory cards have the advantages of small size, large capacities, quick access and easy to install and carry. The use of non-volatile memory systems such as flash memory storage systems is increasing due to the compact physical size of such memory systems, and the ability for non-volatile memory to be repetitively reprogrammed.

A major advantage of flash over ROM is that the memory contents of flash may be changed after the device is manufactured. The ability to repetitively reprogram non-volatile memory included in flash memory storage systems enables flash memory storage systems to be used and reused. Flash memory has found wide acceptance in many types of computers, including desktop computers, mobile phones and hand held computers. Flash memory is also widely used in digital cameras and portable digital music players.

The flash memory is divided into a NAND-type flash memory having a large memory capacity and a NOR-type flash memory having a high processing speed. The NAND-type flash memory, which attains high integration and has a replaceable hand disk, is mostly used to store high integration voices or images. Flash memory storage systems may include flash memory cards and flash memory chip sets. Flash memory chip sets generally include flash memory components and a controller component. A flash memory chip set may be arranged to be assembled into an embedded system. In the case of an MP3 player, a number of digitized audio files in the form of MP3 files are stored in a storage medium included in or coupled to the player in a fashion deemed most suitable to that user.

 

Find the English equivalents in the text.

кишеньковий ПК

носій даних

висока швидкість обробки

убудована система

енергозалежна пам’ять

переваги

 

Definition of a Hard Disk

 

A hard disk drive (HDD) is a digital data storage device that writes and reads data via magnetization changes of a magnetic storage disk along concentric tracks. Computer hard disk drives have become a standard data storage component of modern computer systems and are used in other modern consumer electronics as well. Their proliferation can be directly attributed to their low cost, high storage capacity and high reliability, in addition to wide availability, low power consumption, high data transfer speeds and decreasing physical size.

A hard disk drive contains rigid, disk-shaped platters usually constructed of aluminium or glass. Unlike floppy disks, the platters cannot bend or flex – hence the term hard disk. In most hard disk drives, the platters cannot be removed; for that reason, IBM calls them fixed disk drives. Hard disk drives used to be called Winchester drives. This term dates back to the 1960s, when IBM developed a high-speed hard disk drive that had 30M of fixed-platter storage and 30M of removable-platter storage. The drive had platters that spun at high speeds and heads that floated over the platters while they spun in a sealed environment. That drive, the 30-30 drive, soon received the nickname Winchester after the famous Winchester 30-30 rifle. After that time, drives that used a high-speed spinning platter with a floating head also became known as Winchester drives. The term has no technical or scientific meaning; it is a slang term, and is considered synonymous with hard disk.

A hard drive uses spinning disks with heads that move over the disks and store data in tracks and sectors. The mechanism for reading and writing data on a disk is called an access arm. A track is a concentric ring of information, which is divided into individual sectors that normally store 512 bytes each. The nearer to the circumference of the magnetic disk, the higher the track recording density can be made.

Hard disks usually have multiple platters, each with two sides on which data can be stored. Most drives have at least two or three platters, resulting in four or six sides, and some drives have up to 11 or more platters. The identically positioned tracks on each side of every platter together make up a cylinder. A hard disk drive normally has one head per platter side, and all the heads are mounted on a common carrier device, or rack. The heads move in and out across the disk in unison; they cannot move independently because they are mounted on the same rack.

The heads in most hard disks do not and should not touch the platters during normal operation. When the heads are powered off, however, they land on the platters as they stop spinning. While the drive is on, a very thin cushion of air keeps each head suspended a short distance above or below the platter. If the air cushion is disturbed by a particle of dust or a shock, the head may come into contact with the platter spinning at full speed. When contact with the spinning platters is forceful enough to do damage, the event is called a head crash. The result of a head crash may be anything from a few lost bytes of data to a totally trashed drive. Most drives have special lubricants on the platters and hardened surfaces that can withstand the daily “takeoffs and landings” as well as more severe abuse.

Magnetic drives, such as hard disk drives, operate by using electromagnetism. This basic principle of physics states that as electric current flows through a conductor, a magnetic field is generated around the conductor. This magnetic field then can influence magnetic material in the field. When the direction of the flow of electric current is reversed, the magnetic field’s polarity also is reversed. An electric motor uses electromagnetism to exert pushing and pulling forces on magnets attached to a rotating shaft.

Another effect of electromagnetism is that if a conductor is passed through a changing magnetic field, an electrical current is generated. As the polarity of the magnetic field changes, so does the direction of the electric current flow. For example, a type of electrical generator used in automobiles, called an alternator, operates by rotating electromagnets past coils of wire conductors in which large amounts of electrical current can be induced. The two-way operation of electromagnetism makes it possible to record data on a disk and read that data back later.

The overwhelming majority of the data necessary to operate the hardware and software of the computer is stored on the hard disk drive. The larger the capacity of the hard disk drive, the more data the computer can store. The storage capacity of hard drive is measured in megabytes, gigabytes, or terabytes.

The flow of data to and from the hard disk is managed by a collection of electronic circuits called the hard disk controller. The controller can be built into the disk drive or it can be a separate board in an expansion slot. For personal computers two types of controllers are common, IDE and SCSI. Integrated drive electronics (IDE) controllers can operate one or two hard disk drives. Small computer system interface, or SCSI (pronounced scuzzy), controllers can support multiple disk drives or mix of other SCSI-compatible devices.

 

Comments:

 

proliferation швидке збільшення

access доступ

circumference коло

head crash аварія голівок//непередбачуване зіткнення

рухомих магнітних голівок із поверхнею жорсткого

диска, що призводить до псування даних або

відмови накопичувача

to exert здійснювати

alternator альтернатор, генератор змінного струму

 



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