Учебно-методическое пособие по реферированию и аннотированию текстов на английском языке семей 2010



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Thus abridge to the second language is built on deep structural foundations.

Apart from being much more accurate, such linguistic-knowledge enginesshould, in theory, be reversible—you should be able to work backwards from thetarget language to the source language. In practice, there are a few catches whichprevent this from happening as well as it might - but the architecture does at least

make life easier for software designers trying to produce matching pairs of programs.

Tsunami (English to Japanese) and Typhoon Japanese to English), for instance, sharemuch of their underlying programming code.

Having been designed from the start for use on a personal computer ratherthan a powerful workstation or even a mainframe, Tsunami and Typhoon use memory

extremely efficiently. As a result, they are blindingly fast on the latest PCs—translating either way at speeds of more than 300,000 words an hour. Do they produceperfect translations at the click of a mouse? Not by a long shot. But they do come upwith surprisingly good first drafts for expert translators to get their teeth into. Onemistake that the early researchers made was to imagine that nothing less than flawless,fully automated machine translation would suffice. With more realistic expectations,machine translation is, at last, beginning to thrive.

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IBM promises science 500-fold break-through in supercomputing power

David Stone

PC MAGAZINE March 8, 2005.

Biologists hail SI 00 million project to build a "petaflop" computer as likely to

revolutionize our understanding of cellular biology. The computer, nicknamed 'Blue

Genes', world be around 500 times faster than today's most powerful supercomputer.

Computer scientists say that the planned machine, details of which were revealed last:

week, is the first large leap in computer architecture in decades.

IBM will build the programme around the challenge of modeling protein

folding (see below), with much of the research costs going on designing software. It

will involve 50 scientists from IBM Research's Deep Computing Institute and

Computational Biology Group, and unnamed outside academics.

But Blue Gene's hardware will not he customized to the problem and, if IBM's

blueprint works, it will offer all scientific disciplines petaflop computers. These will

be capable of more than one quadrillion floating point operations ('flop') per second -

around two million times more powerful than today's top desktops. Most experts

have" predicted that fundamental technological difficulties would prevent a petaflop

computer being built before around 2015.

"It is, fantastic that IBM is doing this," says George Lake, a scientist at the

university of Washington and NASA project, scientist for high-performance

computing in Earth and space science. IBM is showing leadership by ushering in a

new generation of supercomputers, he says.

The biggest-technological constraints to building a petaflop machine have been

latency - increasing the speed with which a chip addresses the memory - and reducing

power-consumption. A petaflop computer build using conventional chips would

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consume almost one billion watts of power. IBM reckons Blue Gene will use just one



million-watts.

Although processor speeds have increased exponentially, the time to fetch dm

from the memory of a supercomputer, 300 nanoseconds, is only slightly less than half

what it was 20 years ago. Putting more and more transistors on a chip is therefore

unlikely to lead to much greater speed.

"We set out from scratch, completely ignoring history, and thought how can we

get the highest performance out of silicon," says Monty Denneau, a scientist at IBM's

Thomas J. Watson research center in Yorktown Heights, New York, who is assistant

architect of Slue Gene.

Arvind, a professor of computer science at Mit who is considered one of the top

authorities on computer architecture, applauds IBM's approach. "It has made very big

steps in rethinking computer architecture to try to do without the components that

consume power, it has taken all these research ideas and pulled them together."

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Antiviruses.Principle of work.Examples of antiviruses.

Antivirus software consists of computer programs that attempt to identify,

thwart and eliminate computer viruses and other malicious software (malware).

Antivirus software typically uses two different techniques to accomplish this:

• Examining (scanning) files to look for known viruses matching definitions in a virus

dictionary

• Identifying suspicious behavior from any computer program which might indicate

infection. Such analysis may include data captures, port monitoring and other methods.

Most commercial antivirus software uses both of these approaches, with an

emphasis on the virus dictionary approach.

Historically, the term antivirus has also been used for computer viruses that

spread and combated malicious viruses. This was common on the Amiga computer

platform.

Dictionary

In the virus dictionary approach, when the antivirus software looks at a file, it

refers to a dictionary of known viruses that the authors of the antivirus software have

identified. If a piece of code in the file matches any virus identified in the dictionary,

then the antivirus software can take one of the following actions:

• attempt to repair the file by removing the virus itself from the file

• quarantine the file (such that the file remains inaccessible to other programs and its

virus can no longer spread)

• delete the infected file

To achieve consistent success in the medium and long term, the virus dictionary

approach requires periodic (generally online) downloads of updated virus dictionary

entries. As civically minded and technically inclined users identify new viruses "in the

wild", they can send their infected files to the authors of antivirus software, who then

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include information about the new viruses in their dictionaries.



Dictionary-based antivirus software typically examines files when the computer's operating system creates, opens, closes or e-mails them. In this way it can detect a known virus immediately upon receipt. Note too that a System Administrator can typically schedule the antivirus software to examine (scan) all files on the computer's hard disk on a regular basis. Although the dictionary approach can effectively contain virus outbreaks in the right circumstances, virus authors have tried to stay a step ahead of such software by writing "oligomorphic", "polymorphic" and more recently "metamorphic" viruses, which encrypt parts of themselves or otherwise modify themselves as a method of disguise, so as not to match the virus's signature in the dictionary.

Suspicious behavior

The suspicious behavior approach, by contrast, doesn't attempt to identify

known viruses, but instead monitors the behavior of all programs. If one program tries

to write data to an executable program, for example, the antivirus software can flag

this suspicious behavior, alert a user and ask what to do.

Unlike the dictionary approach, the suspicious behavior approach therefore

provides protection against brand-new viruses that do not yet exist in any virus

dictionaries. However, it can also sound a large number of false positives, and users

probably become desensitized to all the warnings. If the user clicks "Accept" on every

such warning, then the antivirus software obviously gives no benefit to that user. This

problem has worsened since 1997, since many more nonmalicious program designs

came to modify other .exe files without regard to this false positive issue. Thus, most

modern antivirus software uses this technique less and less.

Other approaches

Some antivirus-software uses of other types of heuristic analysis. For example,

it could try to emulate the beginning of the code of each new executable that the

system invokes before transferring control to that executable. If the program seems to

use self-modifying code or otherwise appears as a virus (if it immediately tries to find

other executables, for example), one could assume that a virus has infected the

executable. However, this method could result in a lot of false positives. Yet another

detection method involves using a sandbox. A sandbox emulates the operating system

and runs the executable in this simulation. After the program has terminated, software

analyzes the sandbox for any changes which might indicate a virus. Because of

performance issues, this type of detection normally only takes place during on-

demand scans. Also this method may fail as virus can be nondeterministic and result

in different actions or no actions at all done then run - so it will be impossible to detect

it from one run. Some virus scanners can also warn a user if a file is likely to contain a

virus based on the file type.

An emerging technique to deal with malware in general is whitelisting. Rather

than looking for only known bad software, this technique prevents execution of all

computer code except that which has been previously identified as trustworthy by the

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system administrator. By following this default deny approach, the limitations



inherent in keeping virus signatures up to date are avoided. Additionally, computer

applications that are unwanted by the system administrator are prevented from

executing since they are not on the whitelist. Since modem enterprise organizations

have large quantities of trusted applications, the limitations of adopting this technique

rest with the system administrators' ability to properly inventory and maintain the

whitelist of trusted applications. As such, viable implementations of this technique

include tools for automating the inventory and whitelist maintenance processes.

Issues of concern

• The spread of viruses using e-mail as their infection vector could be inhibited far

more inexpensively and effectively, without the need to install additional antivirus

software; if bugs in e-mail clients, which allow the unauthorized execution of code,

were fixed

• User education can effectively supplement antivirus software. Simply training

users in safe computing practices (such as not downloading and executing unknown

programs from the Internet) would slow the spread of viruses and obviate the need of

much antivirus software.

• The ongoing writing and spreading of viruses and of panic about them gives the

vendors of commercial antivirus software a financial interest in the ongoing existence

of viruses. Some theorize that antivirus companies have financial ties to virus writers,

to generate their own market, though there is currently no evidence for this.

• Some antivirus software can considerably reduce performance. Users may disable

the antivirus protection to overcome the performance loss, thus increasing the risk of

infection. For maximum protection the antivirus software needs to be enabled all the

time — often at the cost of slower performance (see also software bloat).

• It is sometimes necessary to temporarily disable virus protection when installing

major updates such as Windows Service Packs or updating graphics card drivers.

Having antivirus protection running at the same time as installing a major update may

prevent the update installing properly or at all.

• When purchasing antivirus software, the agreement may include a clause that your

subscription will be automatically renewed, and your credit card automatically billed

at the renewal time without your approval. For example, McAfee requires one to

unsubscribe at least 60 days before the expiration of the present subscription, yet it

does not provide phone access nor a way to unsubscribe directly through their website.

In that case, the subscriber's recourse is to contest the charges with the credit card

issuer.

History


There are competing claims for the innovator of the first antivirus product.

Perhaps the first publicly known neutralization of a wild PC virus was performed by

European Bemt Fix (also Bemd) in early 1987. Fix neutralized an infection of the

Vienna virus. Following Vienna a number of highly successful viruses appeared

including Ping Pong, Lehigh, and Suriv-3 aka Jemsalem. In January 1988, researchers

in the Hebrew University developed "unvirus" and "immune", which tell users

whether their disks have been infected and applies an antidote to those that have.

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From 1988 onwards many companies formed with a focus on the new field of



antivirus technology. One of the first breakthroughs in antivirus technology occurred

in March 1988 with the release of the Den Zuk viruses created by Denny Yanuar

Ramdhani of Indonesia. Den Zuk neutralized the Brain virus. April 1988 saw the

Virus-L forum on Usenet created, and mid 1988 saw the development by Peter Tippett

of a heuristic scanner capable of detecting viruses and Trojans which was given a

small public release. Fall 1988 also saw antivirus software Dr. Solomon's Anti-Virus

Toolkit released by Briton Alan Solomon. By December 1990 the market had matured

to the point of nineteen separate antivirus products being on sale including Norton

AntiVirus and ViruScan from McAfee.

Tippett made a number of contributions to the budding field of virus detection.

He was an emergency room doctor who also ran a computer software company. He

had read an article about the Lehigh virus were the first viruses to be developed, but it

was Lehigh that Tippett read about and he questioned whether they would have

similar characteristics to viruses that attack humans. From an epidemiological

viewpoint, he was able to determine how these viruses were affecting systems within

the computer (the boot-sector was affected by the Brain virus, the .com files were

affected by the Lehigh virus, and both .com and .exe files were affected by the

Jemsalem virus).Tippett's company Certus International Corp. then began to create

anti-virus software programs. The company was sold in 1992 to Symantec Corp, and

Tippett went to work for them, incorporating the software he had developed into

Symantec's product, Norton AntiVirus.

Best antivirus soft

NOD32 is an antivirus package made by the Slovak company Eset. Versions are available for Microsoft Windows, Linux, FreeBSD and other platforms. Remote

administration tools for multiuser installations are also available at extra cost. NOD32

Enterprise Edition consists of NOD32 AntiVirus and NOD32 Remote Administrator.

The NOD32 Remote Administrator program allows a network administrator to

monitor anti-virus functions, push installations and upgrades to unprotected PCs on

the network and update configuration files from a central location.

NOD32 is certified by ICSA Labs. It has been tested 44 times by Virus Bulletin

and has failed only 3 times, the lowest failure rate in their tests. At CNET.com, it

received a review of 7.3/10.

Technical information

NOD32 consists of an on-demand scanner and four different real-time monitors.

The on-demand scanner (somewhat confusingly referred to as NOD32) can be

invoked by the scheduler or by the user. Each real-time monitor covers a different

virus entry point:

AMON (Antivirus MONitor) - scans files as they are accessed by the system,

preventing a virus from executing on the system.

DMON (Document MONitor) - scans Microsoft Office documents and files for macro

viruses as they are opened and saved by Office applications.

IMON (Internet MONitor) - intercepts traffic on common protocols such as POPS and

HTTP to detect and intercept viruses before they are saved to disc.

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XMON (MS eXchangeMONitor) - scans incoming and outgoing mail when NODS 2



is running and licensed for Microsoft Exchange Server – i.e, running on a server

environment. This module is not present on workstations at all.

NOD32 Virus Detection Alert

NOD32 is written largely in assembly code, which contributes to its low use of system resources and high scanning speed, meaning that NOD32 can easily process more than 23MB per second while scanning on a modest P4 based PC and on average, with all real-time modules active, uses less than 20MB of memory in total but the physical RAM used by NOD32 is often just a third of that. According to a 2005 Virus Bulletin test, NOD32 performs scans two to five times faster than other antivirus competitors.

In a networked environment NOD32 clients can update from a central "mirror server" on the network, reducing bandwidth usage since new definitions need only be

downloaded once by the mirror server as opposed to once for each client.

NOD32's scan engine uses heuristic detection (which Eset calls "ThreatSense") in

addition to signature files to provide better protection against newly released viruses.

Text 5

What is a virus?



B. Kelley

IOWA STATE UNIVERSITY, PM 1789 Rewised June, 2006.

In 1983, researcher Fred Cohen defined a computer virus as "a program that can

'infect' other programs by modifying them to include a ... version of itself. " This

means that viruses copy themselves, usually by encryption or by mutating slightly

each time they copy.

There are several types of viruses, but the ones that are the most dangerous are

designed to corrupt your computer or software programs. Viruses can range from an

irritating message flashing on your computer screen to eliminating data on your hard

drive. Viruses often use your computer's internal clock as a trigger. Some of the most

popular dates used are Friday the 13th and famous birthdays. It is important to

remember that viruses are dangerous only if you execute (start) an infected program.

There are three main kinds of viruses*. Each kind is based on the way the virus

spreads.


1. Boot Sector Viruses - These viruses attach themselves to floppy disks and

then copy themselves into the boot sector of your hard drive. (The boot sector is the

set of instructions your computer uses when it starts up.) When you start your

computer (or reboot it) your hard drive gets infected. You can get boot sector viruses

only from an infected floppy disk. You cannot get one from sharing files or executing

programs. This type of virus is becoming less common because today's computers do

not require a boot disk to start, but they can still be found on disks that contain other

types of files. One of the most common boot sector viruses is called "Monkey," also

known as "Stoned."

2. Program Viruses - These viruses (also known as traditional file viruses)

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attach themselves to programs' executable files. Usually a program virus will attach to



an .exe or .corn file. However, they can infect any file that your computer runs when it

launches a program (including .sys, .dll, and others). When you start a program that

contains a virus, the virus usually loads into your computer's Memory.

* Three kinds of viruses

1. Boot Sector viruses attach to floppy disks and then copy into the boot sector

of your hard drive.

2. Program viruses attach to a program's executable files.

3. Macro viruses attach to templates.

The truth about viruses

The majority of people believe that the most common source of viruses is the

Internet through e-mail or downloaded files. The truth is however, that the majority of

viruses spread through shared floppy disks or shared files on internal network.

Even if you are not connected to the Internet you should still be concerned

about viruses. You should also be aware that there are thousands of false rumors of

viruses (virushoaxes).

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Использованная литература:



1. Андронов О.Г., Бойко Б.Л. Теоретико-практический курс: Информационная обработка текстов. - М., 1999.

2. Батурина С.А. Сборник текстов для перевода и реферирования.- Омск, 2005

3. Князева Е.Г. Информационная обработка текстов. Учебное пособие – М., 2001.

4. Колодожная Ж.А. Основные понятия об аннотировании и реферировании научных документов.- М.: 2002

5. Маркушевская Л.П., Цапаева Ю.А. Аннотирование и реферирование. (Методические рекомендации для самостоятельной работы студентов) СПб ГУ ИТМО, 2008

6. Славина Г., Харьковский З., Антонова Е. Аннотирование и реферирование. Учебное пособие по английскому языку- М.: Высшая школа, 2006



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