It glossary revision

Put into a space next to each word in the glossary the number of a Unit where it first occurs or where it is essential to the topic discussed, revise the definitions.

Short forms

abbr	abbreviation
adj	adjective
adv	adverb
prep	preposition
sb	somebody
sth	something
v	verb
n	noun

A
access v
accessory n
according to prep
adaptor
adjust v
affect v
algorithm n
align v
animated cartoon n
animation n
appear v
application n
ASCII abbr
attachment n
audio adj
B
background n
back up n, v
band mode n
bandwidth n
bill n
binary adj
blink v
Broadband n
browse v
browser n
button n
C
carbon copy n
categorize v
CD-rewriter n
CD-ROM abbr
character n
chat room n
click v
client n
clip art n
clipboard n
code n
coding system n
combine v
communication n
compatible adj
compose v
computer programmer n
computing n
confident adj
confusing adj
connection n
consistent adj
consumer n
convenient adj
copyright law n
counter n
CPU abbr
crash v
cross-platform adj
cursor n
custom n
cut v
cyberspace n
D
data n
database n
database administrator n
deal with sb v
decrease v
default n
delete v
design n
desktop n
desktop publishing n
detachable adj
develop v
device n
dialog box n
digital adj
dimension n
directory n
Display n
display screen n
distance learning n
DNS abbr
domain name n
double-click v
download v
draft n
drive n
drop-down menu n
dual adj
E
e-commerce n
edit v
e-mail n
emoticon n
empty adj
EPS abbr
erase v
exclude v
existing adj
export v
e-zine n
F
faceplate n
FAQ
feature n
fee n
field n
file n
file extension n
fit v
flame n
Flash n
flip cover n
floppy disk n
folder n
folder n
font n
format v
frame n
freeware n
FTP abbr
function n
G
generate v
GIF abbr
gigabyte n
graph n
graphics n
guarantee n
H
hard disc n
hardware n
high level language n
highlight v
home page n
HTML abbr
HTTP abbr
hyperlink n
I
icon n
illegal adj
image n
imaginative adj
import v
income n
incoming adj
increase v
information technology n
input n
insert v
instant adj
instead of prep
integrate v
interact v
interactive adj
Internet n
IP address n
invasion n
ISDN abbr
J
JavaScript n
JPEG abbr
junk mail n
K
keyboard n
keypad n
keyword n
L
LAN abbr
link v
locate v
location n
logical operator n
M
machine language n
mail server n
manual adj
maximize v
means n
megabyte n
menu bar n
minimize v
mobile phone n
monitor n
mouse n
multilingual adj
multimedia adj
multiple adj
N
narrow v
navigate v
navigation n
navigation bar n
network n
notebook n
O
offline adj, adv
online adj, adv
online community n
operate v
optional adj
organize v
original adj
originate v
outgoing adj
output n
P
paint v
password n
paste v
PC abbr
peer-to-peer adj
performance n
peripheral n
personal information n
personalize v
PICT abbr
plug-in n
pointer n
pop-up ad n
privacy n
privacy policy n
procedure n
process v
program v
protocol n
R
RAM abbr
random adj
real time n
recipient n
Recycle Bin n
register v
related adj
relevant adj
reliable adj
removable disk n
restore v
retailer n
retrieve v
ring tone n
rotate v
run v
S
save v
Save as type v,n
scanner n
screen saver n
scroll bar n
search v
search engine n
secure adj
security n
server n
setting n
share v
shareware n
shortcut n
simulation n
small talk n
smiley n
SMS abbr
software n
source n
spam n
special effects n
specific adj
specification n
stand for sth v
stand-alone adj
standard adj
store v
structure v
stylish adj
subject n
support n
surf v
swap v
system n
T
techno-nerd n
template n
text box n
text editor n
text message n
te4xt wrap n
thesaurus n
3-D adj
TIFF abbr
tool n
toolbar n
tower n
transaction n
transfer v
translate v
transmission n
U
underscore v
unsolicited adj
untitled adj
upload v
URL abbr
utility n
V
videoconference n
vacancy n
view v
violent adj
virtual adj
virtual reality n
virus n
voicemail n
W
Web camera n
Web design n
Web page n
Web-authoring n
Web-based adj
website n
Wi-Fi n
wire cable n
word processor n
WWW abbr

PART 2 ADDITIONAL TEXTS AND VOCABULARY

1 What is the difference between DVD-R/DVD-RW, DVD+R/DVD+RW and DVD-RAM discs?

Ex. 1 Study the active vocabulary

1. single-sided - односторонний

2. single layer - однослойный

3. capacity – емкость

4. eject – выбрасывать

5. eventually – в конечном счете, наконец

6. to be available – быть доступным

7. write-once adj. – предназначенный для одноразовой записи

8. CES (circuit emulation service) – программа эмуляции трафика (позволяет уплотнить потоки голоса и видео с потоком данных при высокоскоростной одновременной асинхронной передаче данных без помощи мультиплексора)

9. to scramble – перемешать, зд. зашифровать

10. to burn a disc – записать (прожечь) диск

11. descrambling code – код расшифровки

12. authoring DVD-Rs – авторский DVD диск

13. retail – продажа в розницу

14. erasable – стираемый

15. RAM (Random Access Memory) – ОЗУ, память произвольного доступа

16. to reuse – повторно использовать

17. compatible – совместимый

18. lossless linking – связь без потерь (обычно при сжатии)

19. drag-and-drop – технология перетаскивания

20. workability – работоспособность

21. data backup – резервное копирование данных

22. to handle - манипулировать

DVD-R and DVD-RW

These 2 disc types were created by the DVD Forum.

Both DVD-R and DVD-RW types generally come in the single-sided, single layer 4.7 GB capacity, which is roughly equal to 120-minutes of standard playing time.

You can also now find 9.4 GB double-sided discs entering the market, although there are no players which will automatically play both sides of the disc without ejecting it and turning it over. Eventually, there will be DVD-R discs available that will hold around 20 GB of data, recorded into two layers on each side of the disc. At this time, these 20gb discs are not yet available.

The most common DVD-R is a write-once 4.7gb disc that comes in two sub-types -- "general purpose" and "authoring". The general purpose discs are part of the industry's copy-protection scheme, which employ CES scrambling to protect movies and music and game discs from being copied. These discs can only be burned by general purpose type DVD writers such as the Pioneer DVR-A04/104/AQ3/103 machines, the Panasonic LF-D311 and D321, Apple Superdrive, etc. Such machines cannot copy the playback descrambling codes on DVD movies or game discs, so they cannot be easily copied. Authoring DVD-Rs must be burned by the Pioneer DVR-S201 DVD Writer, which produces non-copy protected discs for use in the industry for professional, retail DVD duplicators and distributors. Once recorded, either a general or authoring DVD-R can be played on most DVD players (if the player is DVD-R compatible).

By contrast to the write-once DVD-R types, the DVD-RW is fully rewritable or erasable up to 1,000 times. However, unlike the older DVD-RAM format, these particular erasables are NOT "random access", meaning that you cannot erase bits and pieces of them. Instead, you have to completely erase the whole disc to reuse it. The DVD-RW can be played on many DVD players, but not quite as many as the DVD-Rs. Of course, DVD-RAM discs are playable on only a few types of DVD players.

Most DVD-R burners like the Pioneer DVR-104s and compatibles, can also burn DVD-RW discs. An exception is the popular Panasonic DVD burners, which burn only DVD-R and DVD-RAM. This drive is great for users who want both data storage and editing features from DVD-RAM, and DVD-R production capabilities for disc copying and distribution.

DVD-R is the most popular format for most Windows users, and is almost universally accepted by Mac users as their standard DVD recordable format.

DVD+R and DVD+RW

These two types were created and are backed by the DVD+RW Alliance. A few companies who back the DVD Forum (above) are also active in the DVD+RW Alliance, but the two standards are not compatible.

The oldest "plus type" DVD is the DVD+RW. It, like DVD-RW, is a rewriteable 4.7 GB DVD kind of disc. DVD+RW, does have a couple of technical advantages — (1) lossless linking (which enables some editing after recording without a full erasure that DVD-RW requires), (2) up to 2.4X recording speeds on some burners, and (3) a special drag-and-drop file support on the desktop (otherwise known as DVD+MRW). Unfortunately, the DVD+R disc type does NOT even begin to compare with DVD-R as far as DVD playback compatibility. However, the actual level of DVD workability on players of DVD+RW is claimed to be about equal to DVD-RW. Of course, even so, neither the DVD+R nor the older DVD+RW discs are as popular as DVD-R and DVD-RW are.

The newer DVD+R write-once type disc is aimed at becoming more compatible with DVD players. However, the fact is that so far it is only about as compatible as DVD-R discs are. Also, the DVD+R discs are more expensive in today's market, and not burnable by "1st generation" plus-type burners, which were designed only for the DVD+RW rewritable discs. If you want to create +R discs, you'll need the newer "2nd generation" type burners, such as the Sony 120 A, the Ricoh 5125A, and so on.

DVD-RAM is used for data backups and storage, and for editing of video or audio content prior to the production of a final distribution DVD. The DVD-RAM disc type is made to act a lot like a hard drive, where the disc can be formatted for HFS+ Macintosh or Windows type computers, and so on. It can handle 100,000 or more erasures, and should last for many years. Of course it is not playable on many DVD players. Type 2.0 DVD-RAM discs can be removed from their cases to enable playback on the few players in which they are compatible. The newer DVD-RAM drives can handle any sized such disc, including 2.6, 5.2, 4.7 or 9.4 GB discs.

Ex. 2 Complete the chart with  where necessary.

	DVD-R	DVD-RW	DVD+R	DVD+RW	DVD-RAM
Developed by ‘Forum’
Developed by ‘Alliance’
Erasable
Compatible with most DVD-players
Allows editing
Comparatively cheap
Drag-and-drop file support
Lossless linking
Can be burnt by most DVD burners

Ex.3 Translate from Russian into English

1. DVD-R диск обычно поступает в продажу как односторонний, однослойный, вместимостью 4.7 Гб.

2. К сожалению DVD+R еще даже не начал соперничать с DVD-R по совместимости с большинством DVD-проигрывателей.

3. Этот дисковод прекрасно подойдет тем пользователям, которые хотят иметь много места для хранения, возможность редактирования в сочетании с возможностью копирования и распространения.

4. DVD-RAM диски могут проигрываться только на нескольких типах плееров.

5. DVD+R диски на современном рынке чуть дороже.

2 The Real E-mail System ( after Marshall Brain)

Ex. 1. Study the active vocabulary

1. vast majority – огромное большинство

2. server – зд. приложение, предоставляющее услуги (сервисы)

3. server machine – компьютер, предоставляющий услуги

4. SMTP – простой протокол пересылки электронной почты

5. to handle – обрабатывать

6. outgoing/incoming mail – исходящая/поступающая почта

7. POP – протокол почтового офиса

8. IMAP – протокол интерактивного доступа к электронной почте

9. to listen on port 25 – быть настроенным на порт 25

10. e-mail client – клиентская почтовая программа

11. to assume - предполагать

12. ID (identifier) – идентификатор, метка

13. account – абонемент, учетная запись

14. @ (at) – у/на

15. stand-alone – способный работать в автономном режиме

16. to set up – открывать (абонемент)

17. compose a message – составить письмо/послание

18. recipient – получатель

19. body of the message – текст послания

20. IP – Интернет протокол

21. queue – очередь

22. to resend – вновь послать

23. to give up – прекратить попытки

24. RFC – запрос на комментарий

25. to quit/exit/abort/terminate – выйти (из приложения)

26. to telnet - дистанционно подключаться к удаленным станциям, используя протокол эмуляции терминала, т.е. как если бы ваш компьютер был их терминалом

27. to spoof – имитировать соединение, маскируясь под чужим IP адресом, с целью получения доступа к информации

For the vast majority of people right now, the real e-mail system consists of two different servers running on a server machine. One is called the SMTP server, where SMTP stands for Simple Mail Transfer Protocol. The SMTP server handles outgoing mail. The other is either a POP3 server or an IMAP server, both of which handle incoming mail. POP stands for Post Office Protocol, and IMAP stands for Internet Mail Access Protocol. A typical e-mail server looks like this:

The SMTP server listens on well-known port number 25, POP3 listens on port 110 and IMAP uses port 143.

The SMTP Server Whenever you send a piece of e-mail, your e-mail client interacts with the SMTP server to handle the sending. The SMTP server on your host may have conversations with other SMTP servers to actually deliver the e-mail.

Let's assume that I want to send a piece of e-mail. My e-mail ID is brain, and I have my account on howstuffworks.com. I want to send e-mail to jsmith@mindspring.com. I am using a stand-alone e-mail client like Outlook Express.

When I set up my account at howstuffworks, I told Outlook Express the name of the mail server -- mail.howstuffworks.com. When I compose a message and press the Send button, here is what happens:

1. Outlook Express connects to the SMTP server at mail.howstuffworks.com using port 25.

2. Outlook Express has a conversation with the SMTP server, telling the SMTP server the address of the sender and the address of the recipient, as well as the body of the message.

3. The SMTP server takes the "to" address (jsmith@mindspring.com) and breaks it into the recipient name (jsmith) and the domain name (mindspring.com). If the "to" address had been another user at howstuffworks.com, the SMTP server would simply hand the message to the POP3 server for howstuffworks.com (using a little program called the delivery agent). Since the recipient is at another domain, SMTP needs to communicate with that domain.

4. The SMTP server has a conversation with a Domain Name Server, or DNS. It says, "Can you give me the IP address of the SMTP server for mindspring.com?" The DNS replies with the one or more IP addresses for the SMTP server(s) that Mindspring operates.

5. The SMTP server at howstuffworks.com connects with the SMTP server at Mindspring using port 25. It has the same simple text conversation that my e-mail client had with the SMTP server for HowStuffWorks, and gives the message to the Mindspring server. The Mindspring server recognizes that the domain name for jsmith is at Mindspring, so it hands the message to Mindspring's POP3 server, which puts the message in jsmith's mailbox.

If, for some reason, the SMTP server at HowStuffWorks cannot connect with the SMTP server at Mindspring, then the message goes into a queue. The SMTP server on most machines uses a program called sendmail to do the actual sending, so this queue is called the sendmail queue. Sendmail will periodically try to resend the messages in its queue. For example, it might retry every 15 minutes. After four hours, it will usually send you a piece of mail that tells you there is some sort of problem. After five days, most sendmail configurations give up and return the mail to you undelivered.

The actual conversation that an e-mail client has with an SMTP server is specified in public documents called Requests For Comments (RFC). What the e-mail client says is in blue, and what the SMTP server replies is in green. By a set of simple commands the e-mail client introduces itself, indicates the "from" and "to" addresses, delivers the body of the message and then quits. Hackers often telnet to a mail server machine at port 25 trying to have one of these dialogs themselves -- this is how they "spoof" e-mail.

Ex. 2. Which of the following statements are true and which are false?

1. POP3 and IMAP servers handle the in-coming mail. T/F

2. SMTP server uses port 25. T/F

3. Outlook Express is an on-line e-mail client. T/F

4. You can send an e-mail message without setting an account. T/F

5. When you send a message your e-mail client connects to POP3 server. T/F

6. Your e-mail address is broken into two parts. T/F

7. SMTP has to communicate with the DNS even if the sender and the recipient of the e-mail message have their accounts at the same domain. T/F

8. The DNS always replies to SMTP enquiry only with one IP address T/F

9. SMTP server puts the message into the mailbox. T/F

10. The undelivered mail returns every 15 minutes. T/F

Ex. 3. Translate from Russian into English

1. Если SMTP сервер вашего провайдера не может соединиться с SMTP сервером удаленного получателя, сообщение ставится в очередь.

2. Через 4 часа программа Sendmail пришлет вам отчет об ошибке.

3. Запрос на комментарий представляет собой отражение реального обмена информацией клиентской программы с SMTP сервером.

4. Клиентская программа использует набор простых команд для представления, указания на отправителя и получателя.

5. Хакеры могут использовать протокол эмуляции терминала для получения доступа к почте.

3 POP3 and IMAP Servers

Ex. 1. Study the active vocabulary

1. implementation – реализация, разработка

2. to maintain – поддерживать

3. to append – добавлять, присоединять

4. to require – запрашивать

5. password – шифр

6. to log in – зарегистрироваться

7. to access smth – получить доступ к, добраться до

8. to issue commands – выдавать команды

9. unless – если не

10. a variety of machines – различные устройства (компьютеры)

11. to be stuck (Passive от to stick) – задержаться, остаться

12. depending on – в зависимости от

13. whether … or … - или … или…

14. rather than – а не

15. regardless of – независимо от

16. to list – выводить данные в упорядоченном виде

17. message headers – заголовки сообщений

18. to cache – помещать в кэш-память

In the simplest implementations of POP3, the server really does maintain a collection of text files -- one for each e-mail account. When a message arrives, the POP3 server simply appends it to the bottom of the recipient's file!

When you check your e-mail, your e-mail client connects to the POP3 server using port 110. The POP3 server requires an account name and a password. Once you have logged in, the POP3 server opens your text file and allows you to access it. Like the SMTP server, the POP3 server understands a very simple set of text commands.

Your e-mail client connects to the POP3 server and issues a series of commands to download copies of your e-mail messages to your local machine. Generally, it will then delete the messages from the server (unless you've told the e-mail client not to).

Many users want to do far more than that with their e-mail, and they want their e-mail to remain on the server. The main reason for keeping your e-mail on the server is to allow users to connect from a variety of machines. With POP3, once you download your e-mail it is stuck on the machine to which you downloaded it. If you want to read your e-mail both on your desktop machine and your laptop (depending on whether you are working in the office or on the road), POP3 makes life difficult.

IMAP (Internet Mail Access Protocol) is a more advanced protocol that solves these problems. With IMAP, your mail stays on the e-mail server. You can organize your mail into folders, and all the folders live on the server as well. When you search your e-mail, the search occurs on the server machine, rather than on your machine. This approach makes it extremely easy for you to access your e-mail from any machine, and regardless of which machine you use, you have access to all of your mail in all of your folders.

Your e-mail client connects to the IMAP server using port 143. The e-mail client then issues a set of text commands that allow it to do things like list all the folders on the server, list all the message headers in a folder, get a specific e-mail message from the server, delete messages on the server or search through all of the e-mails on the server.

One problem that can arise with IMAP involves this simple question: “If all of my e-mail is stored on the server, then how can I read my mail if I am not connected to the Internet?” To solve this problem, most e-mail clients have some way to cache e-mail on the local machine. For example, the client will download all the messages and store their complete contents on the local machine (just like it would if it were talking to a POP3 server). The messages still exist on the IMAP server, but you now have copies on your machine. This allows you to read and reply to e-mail even if you have no connection to the Internet. The next time you establish a connection, you download all the new messages you received while disconnected and send all the mail that you wrote while disconnected.

Ex. 2. Which of the following statements are true and which are false?

1. An e-mail account is a text file on all POP servers. T/F

2. When the POP3 server checks your e-mail the SMTP server requires an account name and a password. T/F

3. POP3 server issues a series of commands to download copies of your e-mail messages to your local machine T/F

4. E-mail client deletes the messages from the server after downloading them T/F

5. You can tell your e-mail client not to delete the messages T/F

6. The main reason for keeping your e-mail on the server is to allow other users to read it. T/F

7. With the IMAP you can read your e-mail both on your desktop machine and your laptop T/F

8. IMAP uses port 110 T/F

9. With IMAP you can list message headers in the folders T/F

10. The IMAP doesn’t allow you to work off-line T/F

Ex. 3. Translate from Russian into English

1. Приложение POP3 понимает простой набор текстовых команд.

2. Если вы загрузили свою почту с сервера, она остается на вашем компьютере и стирается на сервере.

3. По протоколу IMAP вы получаете доступ к своей почте с любого компьютера.

4. Большинство клиентских программ кэшируют почту на локальном компьютере.

5. Вы читаете и отвечаете на почту даже не имея связи с Интернетом.

4 File Compression: Finding redundancy and looking for patterns (after Tom Harris)

Ex. 1 Study the active vocabulary.

1. redundant – избыточный

2. to list – выводить данные

3. to get rid of – избавляться

4. to refer back to – отсылать к

5. to be familiar with – быть знакомым с

6. inaugural address – речь по случаю вступления в должность

7. quote – цитата

8. space – пробел

9. dash - тире

10. period – точка

11. unit of memory – единица памяти

12. capital and lower-case letters – заглавные и прописные буквы

13. entire – весь, целый

14. accomplish – достигать (цели)

15. to shrink/to compress – сжимать

16. numbered list/index – пронумерованный список

17. number pattern – цифровой шаблон

18. expansion program – программа расширения/восстановления сжатых файлов

19. to save space – сэкономить место

Most types of computer files are fairly redundant -- they have the same information listed over and over again. File-compression programs simply get rid of the redundancy. Instead of listing a piece of information over and over again, a file-compression program lists that information once and then refers back to it whenever it appears in the original program.

As an example, let's look at a type of information we're all familiar with: words.

In John F. Kennedy's 1961 inaugural address, he delivered this famous line:

"Ask not what your country can do for you -- ask what you can do for your country."

The quote has 17 words, made up of 61 letters, 16 spaces, one dash and one period. If each letter, space or punctuation mark takes up one unit of memory, we get a total file size of 79 units. To get the file size down, we need to look for redundancies.

Immediately, we notice that the words "ask", "what", "your", "country", "can" , "do", "for", "you" appear two times. Ignoring the difference between capital and lower-case letters, roughly half of the phrase is redundant. Nine words -- ask, not, what, your, country, can, do, for, you -- give us almost everything we need for the entire quote. To construct the second half of the phrase, we just point to the words in the first half and fill in the spaces and punctuation. Now let’s see how file-compression systems accomplish this.

Most compression programs use a variation of the LZ adaptive dictionary-based algorithm to shrink files. "LZ" refers to Lempel and Ziv, the algorithm's creators.

The system for arranging dictionaries varies, but it could be as simple as a numbered list. When we go through Kennedy's famous words, we pick out the words that are repeated and put them into the numbered index. Then, we simply write the number instead of writing out the whole word.

So, if this is our dictionary: 1. ask 2. what 3. your 4. country 5. can 6. do 7. for 8. you

Our sentence now reads: "1 not 2 3 4 5 6 7 8 -- 1 2 8 5 6 7 3 4"

If you knew the system, you could easily reconstruct the original phrase using only this dictionary and number pattern. This is what the expansion program on your computer does when it expands a downloaded file.

But how much space have we actually saved with this system? We already saw that the full phrase takes up 79 units. Our compressed sentence (including spaces) takes up 37 units, and the dictionary (words and numbers) also takes up 37 units. This gives us a file size of 74, so we haven't reduced the file size by very much.

But this is only one sentence! You can imagine that if the compression program worked through the rest of Kennedy's speech, it would find these words and others repeated many more times.

In fact, most compression programs don’t have any concept of separate words, they only look for patterns. And in order to reduce the file size as much as possible, they carefully select which patterns to include in the dictionary, gradually passing from the shorter (e.g. t__, ou…) to longer strings of repeated signs. This ability to rewrite the dictionary in favour of a better choice is the "adaptive" part of LZ adaptive dictionary-based algorithm. The way programs actually do this is fairly complicated.

If we approach the phrase from this perspective, we may end up with a completely different dictionary: 1. ask__ 2. what__ 3. you 4. r__country 5. __can__do__for__you (__ here stands for spaces)

John F. Kennedy’s famous line is thus compressed to: "1not__2345__--__12354"

The sentence now takes up 18 units of memory, and our dictionary takes up 41 units. So we've compressed the total file size from 79 units to 59 units! This is just one more way of compressing the phrase, and not necessarily the most efficient one.

Ex. 2. Put questions to which the following phrases are the answers

1. ____________________________________________

of the redundancy.

2. ­­­­­­­­____________________________________________

whenever it appears in the original program.

3. ____________________________________________

John F. Kennedy’s

4. ____________________________________________

17 words

5._____________________________________________

one unit of memory

6. _____________________________________________

two times

7. _____________________________________________

LZ adaptive dictionary-based algorithm

8. _____________________________________________

words that are repeated

9. _____________________________________________

concept of separate words

10. ____________________________________________

This ability to rewrite the dictionary in favour of a better choice

Ex. 3 Translate from Russian into English

1. Девять слов дают нам почти все, что нужно для всей цитаты.

2. Буквы L и Z относятся к Лемпелю и Зиву, математикам, создателям алгоритма.

3. Мы попросту пишем цифру вместо целого слова.

4. Если мы подойдем к фразе с этой стороны, то можем получить другой словарь.

5. Программа тщательно отбирает, какие шаблоны включить в словарь.

5 File Compression: The file-reduction ratio. Lossy and Lossless (after Tom Harris)

Ex.1 Study the active vocabulary

1. file-reduction ratio – процент сокращения файла

2. scheme [ski:m] – схема

3. good-sized file – файл достаточно большого размера

4. frequently – часто

5. set pattern – установленный шаблон

6. unique – уникальный

7. entry – словарная статья, запись в словаре

8. pervasive patterns – шаблоны широкого охвата

9. to emerge – появиться

10. to be suited to – быть приспособленным для

11. to pick up – выбирать

12. succinctly [sB`ksNEktlN] – кратко и ясно

13. the manner of execution – способ выполнения (команд)

14. lossless – без потерь информации

15. lossy – с частичной потерей информации

16. to recreate – воссоздать

17. to put back together – восстановить

18. on the other end – в другом месте

19. to eliminate – убрать (информацию)

20. to tailor the file – обрезать файл

21. bitmap picture – растровое изображение

22. to tend to – иметь обыкновение

23. fairly bulky – довольно объемный

24. pixel – точка растра

25. to compromise resolution – искажать разрешение

26. colour value – значение цвета

27. to be stuck with – быть вынужденным заниматься чем-либо

28. to reproduce exactly – воспроизводить в точности

The file-reduction ratio depends on a number of factors, including file type, file size and compression scheme.

In most languages of the world, certain letters and words often appear together in the same pattern. Because of this high rate of redundancy, text files compress very well. A reduction of 50 percent or more is typical for a good-sized text file. Most programming languages are also very redundant because they use a relatively small collection of commands, which frequently go together in a set pattern. Files that include a lot of unique information, such as graphics or MP3 files, cannot be compressed much with this system because they don't repeat many patterns.

If a file has a lot of repeated patterns, the rate of reduction typically increases with file size. You can see this just by looking at our example -- if we had more of Kennedy's speech, we would be able to refer to the patterns in our dictionary more often, and so get more out of each entry's file space. Also, more pervasive patterns might emerge in the longer work, allowing us to create a more efficient dictionary.

This efficiency also depends on the specific algorithm used by the compression program. Some programs are particularly suited to picking up patterns in certain types of files, and so may compress them more succinctly. Others have dictionaries within dictionaries, which might compress efficiently for larger files but not for smaller ones. While all compression programs of this sort work with the same basic idea, there is actually a good deal of variation in the manner of execution. Programmers are always trying to build a better system.

The type of compression we've been discussing here is called lossless compression, because it lets you recreate the original file exactly. All lossless compression is based on the idea of breaking a file into a "smaller" form for transmission or storage and then putting it back together on the other end so it can be used again.

Lossy compression works very differently. These programs simply eliminate "unnecessary" bits of information, tailoring the file so that it is smaller. This type of compression is used a lot for reducing the file size of bitmap pictures, which tend to be fairly bulky. To see how this works, let's consider how your computer might compress a scanned photograph.

A lossless compression program can't do much with this type of file. While large parts of the picture may look the same -- the whole sky is blue, for example -- most of the individual pixels are a little bit different. To make this picture smaller without compromising the resolution, you have to change the color value for certain pixels. If the picture had a lot of blue sky, the program would pick one color of blue that could be used for every pixel. Then, the program rewrites the file so that the value for every sky pixel refers back to this information. If the compression scheme works well, you won't notice the change, but the file size will be significantly reduced.

Of course, with lossy compression, you can't get the original file back after it has been compressed. You're stuck with the compression program's reinterpretation of the original. For this reason, you can't use this sort of compression for anything that needs to be reproduced exactly, including software applications, databases and presidential inauguration speeches.

Ex. 2. Put questions to which the following phrases are the answers

1. __________________________________________________

on a number of factors

2. __________________________________________________

50%

3. __________________________________________________

graphics or MP3 files

4. __________________________________________________

If a file has a lot of repeated patterns

5. __________________________________________________

more pervasive patterns

6. __________________________________________________

the specific algorithm used by the compression program

7. __________________________________________________

in the manner of execution

8. __________________________________________________

the idea of breaking a file into a "smaller" form

9. __________________________________________________

"unnecessary" bits of information

10. __________________________________________________

for reducing the file size of bitmap pictures

Ex. 3. Translate from Russian into English

1. Хотя большие части картинки схожи, их индивидуальные пиксели различны.

2. Чтобы уменьшить картинку, приходится менять значения цвета для пикселей.

3. Если модель сжатия работает хорошо, вы не заметите разницы.

4. При сжатии с частичной потерей данных нельзя восстановить файл-оригинал.

5. Базы данных следует воспроизводить в точности.

6 AGP graphics card: Getting Off the Bus

(after Robert Valdes and Jeff Tyson)

Ex. 1 Study the active vocabulary

1. AGP (Accelerated Graphics Port) – ускоренный графический порт

2. streaming video – потоковое видео

3. real-time-rendered – передаваемый в реальном времени (т.е. без записи всего видео-файла на жесткий диск)

4. prevalent – преобладающий

5. PCI (Peripheral Component Interconnect) – межсоединение периферийных компонентов

6. bus – шина

7. simultaneously – одновременно

8. to wait in line – ждать в очереди

9. long in the tooth – разг. старый

10. to address the area – обращаться к области

11. data bottleneck – задержка пропуска данных

12. to clear the traffic jams – расчищать пробки

13. to render/deliver/transport/transfer graphics – передавать графику

14. overall drag – общая задержка

15. dedicated port – выделенный порт

16. capacity of the connection – пропусканная способность соединения

17. pipelining of the data packets – сцепление, конвейеризация пакетов передаваемых данных

18. request – запрос

19. height-length-width – высота-длина-ширина

20. to take up room – занимать место

21. sideband addressing – вынесенная (за пределы пакета) адресация

22. to issue (address) lines – добавлять адресные строки

23. bandwidth – полоса пропускания, количество данных, которое может быть переслано по шине за секунду

24. to unclog resources – высвобождать ресурсы

In 1996, Intel introduced AGP (or Accelerated Graphics Port) as a more efficient way to deliver the streaming video and real-time-rendered 3-D graphics that were becoming more prevalent in all aspects of computing. Previously, the standard method of delivery was the Peripheral Component Interconnect (PCI) bus. The PCI bus is a path used to deliver information from the graphics card to the central processing unit (CPU). A bus allows multiple packets of information from different sources to travel down one path simultaneously. Information from the graphics card travels through the bus along with any other information that is coming from a device connected to the PCI. When all the information arrives at the CPU, it has to wait in line to get time with the CPU.

This system worked well for many years, but eventually the PCI bus became a little long in the tooth. The Internet and most software were more and more graphically oriented, and the demands of the graphics card needed priority over all other PCI devices.

AGP is built on the idea of improving the ways that PCI transports data to the CPU. Intel achieved this by addressing all of the areas where PCI transfers were causing data bottlenecks in the system. By clearing the traffic jams of data, AGP increases the speed at which machines can render graphics while using the system's resources more efficiently to reduce overall drag. Here's how:

• Dedicated Port - There are no other devices connected to the AGP other than the graphics card. With a dedicated path to the CPU, the graphics card can always operate at the maximum capacity of the connection.

• Pipelining - This method of data organization allows the graphics card to receive and respond to multiple packets of data in a single request. Here's a simplified example of this:

With AGP, the graphics card can receive a request for all of the information needed to render a particular image and send it out all at once. With PCI, the graphics card would receive information on the height of the image and wait... then the length of the image, and wait... then the width of the image, and wait... combine the data, and then send it out.

• Sideband addressing - Like a letter, all requests and information sent from one part of your computer to the next must have an address containing "To" and "From." The problem with PCI is that this "To" and "From" information is sent with the working data all together in one packet. This is the equivalent of including an address card inside the envelope when you send a letter to a friend: Now the post office has to open the envelope to see the address in order to know where to send it. This takes up the post office's time. In addition, the address card itself takes up room in the envelope, reducing the total amount of stuff you can send to your friend.

With sideband addressing, the AGP issues eight additional lines on the data packet just for addressing. This puts the address on the outside of the envelope, so to speak, freeing up the total bandwidth of the data path used to transfer information back and forth. In addition, it unclogs system resources that were previously used to open the packet to read the addresses.

Ex. 2 Which of the following statements are true and which are false?

1. By 1996 AGP had become prevalent in all aspects of computing. T/F

2. Information from the graphics card travels down PCI bus alongside with packets of data from other devices. T/F

3. The data from the PCI graphics card is immediately processed by the CPU. T/F

4. Eventually the PCI bus became old. T/F

5. AGP is essentially different from PCI. T/F

6. AGP clears the traffic jams of data. T/F

7. Dedicated port means that only devices that have to do with graphics are connected to that port T/F

8. Pipelining means that the graphics card will wait for all packets of information on particular image to come, then it will combine the data and send it out. T/F

9. With PCI packets of information have to be opened in order to know where to send them T/F

10. With AGP two additional lines “To” and “From” are added to packets just for addressing T/F

Ex.3 Translate from Russian into English

1. Шина PCI позволяет одновременно пересылать много пакетов информации.

2. Графические карты требовали приоритета перед другими PCI устройствами.

3. Интел обратилась ко всем областям, где передача данных по шине вызывала информационные пробки.

4. Карточка с адресом сама занимает место в конверте.

5. Добавление адресных строк высвобождает всю полосу пропускания шины.

7 AGP graphics card: Saving RAM

(after Robert Valdes and Jeff Tyson)

Ex. 1 Study the active vocabulary

1. to waste RAM – тратить оперативную память

2. to best – победить

3. predecessor - предшественник

4. to streamline – рационализировать (процесс)

5. texture map – карта отображения текстуры

6. wrapping paper – оберточная бумага

7. flat, 2-D image – плоская, двухмерная картинка

8. to drain the memory – использовать память

9. overall – в целом

10. framebuffer – буфер кадров

11. overall performance – общая производительность

12. to designate RAM – маркировать оперативную память

13. on-the-fly – на лету, в реальном времени

14. abundant memory - обширная память

15. trickery – хитрость

16. chipset – набор микросхем

17. Graphics Address Remapping Table (GART) – таблица переназначения адресов графики

18. bits and pieces – отдельные биты и куски

PCI: Wasting RAM

Speed is not the only area where AGP has bested its predecessor. It also streamlines the process of rendering graphics by using system memory more efficiently.

Any 3-D graphic you see on your computer is built by a texture map. Texture maps are like wrapping paper. Your computer takes a flat, 2-D image and wraps it around a set of parameters dictated by the graphics card to create the appearance of a 3-D image. Think of this as wrapping an invisible box with wrapping paper to show the size of the box. It is important to understand this because the creation and storage of texture maps is the main thing that drains the memory from both the graphics card and the system overall.

With a PCI-based graphics card, every texture map has to be stored twice. First, the texture map is loaded from the hard drive to the system memory (RAM) until it has to be used. Once it is needed, it is pulled from memory and sent to the CPU to be processed. Once processed, it is sent through the PCI bus to the graphics card, where it is stored again in the card's framebuffer. The framebuffer is where the graphics card holds the image in storage once it has been rendered so that it can be refreshed every time it is needed. All of this storing and sending between the system and the card is very draining to the overall performance of the computer.

AGP improves the process of storing texture maps by allowing the operating system to designate RAM for use by the graphics card on the fly. This type of memory is called AGP memory or non-local video memory. Using the much more abundant and faster RAM used by the operating system to store texture maps reduces the number of maps that have to be stored on the graphics card's memory. In addition, the size of the texture map your computer is capable of processing is no longer limited to the amount of RAM on the graphics card.

The other way AGP saves RAM is by only storing texture maps once. It does this with a little trickery. This trickery takes the form of a chipset called the Graphics Address Remapping Table (GART). GART takes the portion of the system memory that the AGP borrows to store texture maps for the graphics card and re-addresses it. The new address provided by GART makes the CPU think that the texture map is being stored in the card's framebuffer. GART may be putting bits and pieces of the map all over the system RAM; but when the CPU needs it, as far as it's concerned the texture map is right where it should be.

Ex. 2 Which of the following statements are true and which are false?

1. Speed is the only area where AGP has bested its predecessor. T/F

2. With PCI-based graphics card, operating system dictates parameters for turning a flat image into a 3-D image. T/F

3. Creation and storage of texture maps drains only the graphics card memory. T/F

4. The system memory is called RAM. T/F

5. The texture maps are stored on the hard drive T/F

6. Texture maps are processed by the graphics card. T/F

7. With PCI-based graphics card, refreshing the images is the task of the CPU. T/F

8. AGP memory is the RAM-based memory T/F

9. Framebuffer memory is faster than RAM. T/F

10. GART readdresses bits and pieces of images within the framebuffer memory. T/F

Ex. 3 Translate from Russian into English.

1. Невидимый ящик как бы оборачивают бумагой, чтобы показать его размер.

2. Размер карт отображения текстуры не ограничен собственной памятью видео-карты.

3. Хитрость принимает форму набора микросхем для таблицы переназначения адресов графики.

4. Хранение и пересылка кадров между системой и видео-картой замедляет быстродействие компьютера в целом.

5. Таблица переназначения размещает биты и куски крт в разных частях оперативной памяти.

8 3-D Graphics: Making It Look Like the Real Thing by Shapes, Surface Textures, Lighting (after Curt Franklin)

Ex. 1 Study the active vocabulary

1. surface texture – поверхностная текстура, свойства поверхности графического объекта, заданные рядом параметров

2. lighting - освещение

3. anti-aliasing – сглаживание ступенчатости кривых

4. straight line – прямая

5. curve – кривая

6. square – квадрат

7. rectangle – прямоугольник

8. circle – круг

9. triangle – треугольник

10. smooth – плавный (о кривой)

11. wireframe – каркас

12. eventually – в конечном счете

13. to picture – изображать

14. polygon – элементарный многоугольник

15. key way – основной способ

16. from several angles – с нескольких углов (зрения)

17. bumps and craters – бугорки и ямки

18. reflectance – коэффициент отражения, отражательная способность

19. sharp – четкий, резкий

20. fuzzy – нечеткий

21. ranging from … to … – в диапазоне от … и до…

22. frog skin – кожа лягушки, пупырчатая поверхность

23. Jell-o gelatin – желеобразный студень

24. to shatter illusion – разбить иллюзию

25. ray-tracing – метод трассировки лучей

26. to plot the path – рассчитать траекторию

27. light ray – луч света

28. bulb - лампочка

29. to bounce off - отражаться

30. appearance of weight and solidity – видимость веса и твердости

31. shading and shadows – затенение (штриховка) и тени

32. to reinforce – усилить

33. to anchor – прикреплять, привязывать к какой-либо поверхности

A number of image parts go into making an object seem real, that is 3-D. Among the most important of these are shapes, surface textures, lighting, perspective, depth of field and anti-aliasing.

Shapes

When we look out our windows, we see scenes made up of all sorts of shapes, with straight lines and curves in many sizes and combinations. Similarly, when we look at a 3-D graphical image on our computer monitor, we see images made up of a variety of shapes. We see squares, rectangles, parallelograms, circles and rhomboids, but most of all we see triangles. However, in order to build images that look as though they have the smooth curves often found in nature, some of the shapes must be very small, and a complex image – say , a human body – might require thousands of these shapes to be put together into a structure called a wireframe. At this stage the structure might be recognizable as the symbol of whatever it will eventually picture, but the next major step is important: The wireframe has to be given a surface.

Pic.1 This illustration shows the wireframe of a hand made from relatively few polygons – 862 total.

Pic. 2 The outline of the wireframe can be made to look more natural and rounded, but many more polygons – 3,444 – are required.

Surface textures

When we meet a surface in the real world, we can get information about it in two key ways. We can look at it, sometimes from several angles, and we can touch it to see whether it's hard or soft. In a 3-D graphic image, however, we can only look at the surface to get all the information possible. All that information breaks down into three areas:

• Color: What color is it? Is it the same color all over?

• Texture: Does it appear to be smooth, or does it have lines, bumps, craters or some other irregularity on the surface?

• Reflectance: How much light does it reflect? Are reflections of other items in the surface sharp or fuzzy?

O ne way to make an image look "real" is to have a wide variety of these three features across the different parts of the image. Look around you now: Your computer keyboard has a different color/texture/reflectance than your desktop, which has a different color/texture/reflectance than your arm. For realistic color, it’s important for the computer to be able to choose from millions of different colors for the pixels making up an image. variety in texture comes both from mathematical models for surfaces ranging from frog skin to Jell-o gelatin and stored “texture maps” that are applied to surfaces. We also associate qualities that we can't see – soft, hard, warm, cold – with particular combinations of color, texture and reflectance. If one of them is wrong, the illusion of reality is shattered.

Adding a surface to the wireframe begins to change the image from something obviously mathematical to a picture we might recognize as a hand.

Lighting

When you walk into a room, you turn on a light. You probably don't spend a lot of time thinking about the way the light comes from the bulb or tube and spreads around the room. But the people making 3-D graphics have to think about it, because all the surfaces surrounding the wireframes have to be lit from somewhere. One technique, called ray-tracing, plots the path that imaginary light rays take as they leave the bulb, bounce off of mirrors, walls and other reflecting surfaces, and finally land on items at different intensities from varying angles.

L ighting plays a key role in two effects that give the appearance of weight and solidity to objects: shading and shadows. The first, shading, takes place when the light shining on an object is stronger on one side than on the other. This shading is what makes a ball look round. The differences in light intensity work with shape to reinforce the illusion that an object has depth as well as height and width. The illusion of weight comes from the second effect – shadows.

Lighting “anchors” objects to the ground with shadows.

Ex. 2 Decide which of the following statements are true and which are false

1. The most frequent shapes in synthetic images are circles and rectangles. T/F

2. Smooth curves are very seldom found in nature. T/F

3. The structure of a human body is called the wireframe. T/F

4. Polygons may have many angles. T/F

5. We can get information about the surface in virtual 3-D world by touching it. T/F

6. Variety of textures comes from mathematical models for surfaces and texture maps. T/F

7. Particular combinations of colour/texture/reflectance may be associated with softness. T/F

8. Ray tracing has to do with optics and geometry. T/F

9. Shading and shadows are synonyms. T/F

10. Height and width are real measurements on display, but depth and weight are illusions. T/F

Ex. 3 Translate from Russian into English

1. Картины, которые мы видим, составлены из комбинаций различных форм.

2. Математическая структура может быть узнаваема как символ отображаемого.

3. Каркас должен получить поверхность.

4. Штриховка делает шар круглым.

5. Клавиатура отлична от системного блока по комбинации цвета, текстуры, коэффициент отражения.

9 3-D Graphics: Making It Look Like the Real Thing by Perspective, Depth of Field and Anti-aliasing

Ex.1 Study the active vocabulary

1. to converge - сходиться в одной точке

2. vanishing point – точка исчезновения (на линии горизонта)

3. partially – частично

4. to block the view – загораживать вид

5. Z-buffer – буфер глубины

6. axis – ось (координат)

7. to assign a number/value – присваивать числовое значение (переменной)

8. front of the scene – передний край сцены/картинки

9. to figure out – решать

10. in a straightforward way – прямолинейно

11. to intersect – пересекаться

12. background items – предметы заднего плана

13. foreground – передний план

14. to be out of focus – быть не в фокусе, размытым

15. to reinforce the illusion – усилить иллюзию

16. regardless of distance – независимо от расстояния

17. to seem foreign - казаться неестественным

18. to rely on fooling the eye – полагаться на обман зрения

19. graduated shades of the color – градуированные оттенки цвета

20. “grayed-out” pixels – полутоновые пиксели

21. jagged stair steps – острые ступенчатые переходы

22. to blur – размывать, делать нерезким

Perspective

Perspective is one of those words that sounds technical but that actually describes a simple effect everyone has seen. If you stand on the side of a long, straight road and look into the distance, it appears as if the two sides of the road come together in a point at the horizon. Also, if trees are standing next to the road, the trees farther away will look smaller than the trees close to you. When all of the objects in a scene look like they will eventually converge at a single point in the distance, that's perspective. There are variations, but most 3-D graphics use the "single point perspective" just described.

In the illustration, the hands are separate, but most scenes feature some items in front of, and partially blocking the view of, other items. For these scenes the software not only must calculate the relative sizes of the items but also must know which item is in front and how much of the other items it hides. The most common technique for calculating these factors is the Z-Buffer. The Z-buffer gets its name from the common label for the axis, or imaginary line, going from the screen back through the scene to the horizon. (There are two other common axes to consider: the x-axis, which measures the scene from side to side, and the y-axis, which measures the scene from top to bottom.)

The Z-buffer assigns to each polygon a number based on how close an object containing the polygon is to the front of the scene. Generally, lower numbers are assigned to items closer to the screen, and higher numbers are assigned to items closer to the horizon. For example, a 16-bit Z-buffer would assign the number -32,768 to an object rendered as close to the screen as possible and 32,767 to an object that is as far away as possible.

In the real world, our eyes can’t see objects behind others, so we don’t have the problem of figuring out what we should be seeing. But the computer faces this problem constantly and solves it in a straightforward way. As each object is created, its Z-value is compared to that of other objects that occupy the same x- and y-values. The object with the lowest z-value is fully rendered, while objects with higher z-values aren’t rendered where they intersect. The result ensures that we don’t see background items appearing through the middle of characters in the foreground. Since the z-buffer is employed before objects are fully rendered, pieces of the scene that are hidden behind characters or objects don’t have to be rendered at all. This speeds up graphics performance.

Depth of Field

Another optical effect successfully used to create 3-D is depth of field. Using our example of the trees beside the road, as that line of trees gets smaller, another interesting thing happens. If you look at the trees close to you, the trees farther away will appear to be out of focus. And this is especially true when you're looking at a photograph or movie of the trees. Film directors and computer animators use this depth of field effect for two purposes. The first is to reinforce the illusion of depth in the scene you're watching. It's certainly possible for the computer to make sure that every item in a scene, no matter how near or far it's supposed to be, is perfectly in focus. Since we're used to seeing the depth of field effect, though, having items in focus regardless of distance would seem foreign and would disturb the illusion of watching a scene in the real world.

The second reason directors use depth of field is to focus your attention on the items or actors they feel are most important. To direct your attention to the heroine of a movie, for example, a director might use a "shallow depth of field," where only the actor is in focus. A scene that's designed to impress you with the grandeur of nature, on the other hand, might use a "deep depth of field" to get as much as possible in focus and noticeable.

A nti-aliasing

A technique that also relies on fooling the eye is anti-aliasing. Digital graphics systems are very good at creating lines that go straight up and down the screen, or straight across. But when curves or diagonal lines show up (and they show up pretty often in the real world), the computer might produce lines that resemble stair steps instead of smooth flows. So to fool your eye into seeing a smooth curve or line, the computer can add graduated shades of the color in the line to the pixels surrounding the line. These "grayed-out" pixels will fool your eye into thinking that the jagged stair steps are gone.

The jagged “stair steps” that occur when images are painted from pixels in straight lines mark an object as obviously computer-generated.

Drawing gray pixels around the lines of an image -- “blurring” the lines -- minimizes the stair steps and makes an object appear more realistic.

Ex. 2 . Decide which of the following statements are true and which are false

1. The word “perspective” has both general and special meaning. T/F

2. The vanishing point is always at the horizon. T/F

3. Z-buffer is an imaginary line going from the screen back through the scene to horizon. T/F

4. Numbers that Z-buffer assigns to the polygons are based on their relative size. T/F

5. Computer-generated objects may have identical X- Y- and Z-values. T/F

6. The object with the highest Z-value is fully rendered. T/F

7. CPU doesn’t have to calculate polygons for hidden pieces of scenes. T/F

8. All film directors know and use the effect of the depth of the field. T/F

9. People in real life can see all items of the scene in focus regardless of distance. T/F

10. Computers can equally realistically render both straight lines and curves. T/F

Ex. 3 Translate from Russian into English

1. Большинство программ 3-D графики используют не-стереоскопическую перспективу.

2. Режиссеры используют эффект глубина поля, чтобы сфокусировать внимание на актере.

3. Цифровые графические системы хороши для отображения прямых линий.

4. Компьютер добавляет полутоны к пикселям, окружающим кривую.

5. 16-битовый Z-буфер присвоит значение -32768 ближайшему к экрану объекту.

10

The future of PC: EUVL Chipmaking (after Jeff Tyson)

Ex. 1. Study the active vocabulary