Test yourself 2 страница

"It seems like computerization gave rise to one more misfortune - passion for the Internet", - is announced in "Canadian Medical Association Journal". Doctor Yang observed 496 patients, 396 of them had unhealthy passion for the Internet. She noted that in its nature this phenomenon resembles alcoholism or irresistible craving for gambling. In the journal it is underlined that those who have a computer at home are under the greatest risks.

As experience shows, the ideas of protection against a negative influence of torsion fields of PC displays and other electronic equipment are accepted with difficulty. However, one should not forget that there are the numerous proofs of a negative influence of PC displays on users even in the presence of protective devices in the form of filters of different modification. The science should deal with explanation of the mentioned facts, because, as I. I. Pavlov said, "facts are the air of science". Even if they are beyond the conceptions worked out by science.

The traditional reasons are conditioned by the conceptions formed in the science and relate not only to the problems of users' protection against PC displays negative impact but as well to practically all incipient branches of scientific knowledge. The American scientific sociologist Kun in his book "The structure of scientific revolutions" shows that wide scientific community begins to accept experimental results which are beyond the generally accepted theoretical concepts, as a rule, after appearance of hypotheses, concepts, theories, in whose framework their scientific interpretation is possible. Until this, paradoxical facts are ignored; scientists do not take them into account in their activity.

The spread of new ideas goes, as a rule, simultaneously with the appearance of a new generation of scientists who are free from the burden of past, obsolescent concepts, and they become thus the bearers of the ideas of a new paradigm.

8. Read and discuss the article. Why do you think some people are inclined to using jargon?

Why are these bit streams of weird words more than just a conspiracy designed to confuse the innocent? Explain your opinion, using specific reasons and examples to support your answer.

CHASING THE JARGON JITTERS.

By Steve Pinker (Steven Pinker, professor of cognitive sci­ence at M.I.T., is author of The Language Instinct (HarperCollins).

RAM, ROM, MIPS, FLOPS, CPUS, IRQs, asynchronous floating­point multitasking initial­ization delimiters—why do computers breed so much godawful jargon? Is it all a bunch of incantations muttered by the wireheads to intimidate new users (or, as they call us, lusers)? Will digital argot corrupt the English language, leading future gen­erations to mumble in the acronym-clot­ted gobbledygook of computer manuals? Negative. Computer jargon is inevit­able, even welcome. As far as jargon goes, it's not so bad, and English will be the bet­ter for it.

Jargon, like cholesterol, comes in good and bad kinds. One of the bad kinds is government doublespeak: pacification (bombing), inoperative statement (lie), revenue enhancement (taxes), energetic disassembly (what happened at Cher­nobyl). Another is social-science baffle­gab: high-falutin' lingo, like strategized interpersonal programmatics and amel­iorative contextual interactions, that hides the fact that the academician is talk­ing about banalities or nothing at all. Then there are the rapidly changing shibboleths and code words that separate the elite from the rabble, the cool from the dweebs. But sometimes sincere, plainspeaking folks simply need names for things. Knit­ting, golf, cooking, fly fishing, bridge - every specialized activity evolves its own jargon. Just as Adam had to give names to every beast of the field and every fowl of the air, the first person who wants to identify a new gizmo to a listener has to figure out what kind of noise to make to get the idea across. Language provides two options. One is to cobble together a phrase describing the gizmo. When biblical Hebrew was revived in Israel and had to be embellished to meet 20th century demands, the first translation of microscope was "the device that makes the hyssop on the wall lock like the cedars of Lebanon." It's clear, poetic even, but if you imagine a conversation among harried lab technicians, you immediately see the problem. The option at the other extreme is to coin a nice, simple word, like flurg. That's short and sweet, but unless you are a member of a clique who is in contact with the dubber and have memorized the coin­age, it's gibberish. Clarity and conciseness trade off; you can be either clear and ver­bose or concise and opaque.

Most jargon starts off near the clear but long-winded end of the trade-off. New words are manufactured by gluing old ones together, adding prefixes and suffixes and borrowing words from other languages. But as people become familiar with a term, they try to keep the attention of their listeners by abbreviating it. Frequently used words inexorably slide toward the short and opaque end of the continuum. If Benjamin Franklin were transported from the 18thcentury to the first half of this century, he could make educated guesses about the meanings of refrigerator, television and even facsimile ("make similar"). But were he to arrive in the second half, fridge, TV and fax would leave him baffled.

Computer jargon has its share of the unwieldy turned unclear. Disk Operating System becomes DOS; modulator-demod­ulator becomes modem; multiplexer be­comes mux. But some of it is downright cuddly— mouse, floppy, handshake, bug, shareware, number crunching, snarfing and readme files, for example. Who let them in? To answer the question, you have to know two more jargon words, which identify the main cultures of computing: the hackers and the suits.

Contrary to media usage, "hackers" are not pranksters who break into mainframe computers and accidentally start World War III or, worse, the loathsome creeps who devise and spread viruses in real life.

Those are "crackers."A hacker is a member of an unofficial meritocracy whose mem­bers are distinguished by their ability to program quickly and enthusiastically. They do not fit the stereotype of the pasty-faced, polyester-clad, pocket-protected need-a-lifes. Rather, they are literate, articulate quasi-hippies, and their culture esteems precise, witty wordplay.

Eric Raymond's The New Hacker's Dictionary (M.I.T. Press) provides a glimpse of the vast lexicon that supplies the friendlier examples of our computer jargon. By analogy to a typo, absentminded hackers can make a thinko or a braino. Exiting a window on the screen is defenes­trating; leaving off the page numbers at the foot of a printed document is depedatating it ("cutting off its feet," by analogy with decapitating). A poorly designed pro­gram might be barfulous (nauseating) or display a high degree of bogosity. Such bogotified programs can be detected with that hypothetical but indispensable instru­ment, the "bogometer." Bogometers are also useful in the presence of politicians, professors with a Theory of Everything and, most of all, the dreaded suits.

The Hacker's Dictionary defines suit as follows: "1. Ugly and uncomfortable business clothing' often worn by non-hackers. Invariably worn with a 'tie,' a strangulation device that partially cuts off the blood supply to the brain. It is thought that this explains much about the behavior of suit wearers. 2. A person who habitually wears suits. See loser, burble, manage­ment and brain-damaged." Hackers are exasperated by the suits' breathless prom­ises to customers of features that are ex­tremely difficult to program or that violate the laws of physics and even more con­temptuous of their buzz word-laden ad-speak (synergy, interface), their inelegant neologisms (prioritize, securitize) and their technical malaprops (such as para­meter referring to limits rather than to dimension of variation). At least to hear the hackers talk, the more awful computer jar­gon can be attributed to management.

But putting aside who is to blame for all that lingo, what's a poor luser to do? The answer is certainly not to sit down and mem­orize a glossary as if it were high school Latin homework. Instead think of the cir­cumstances in which you actually welcome jargon. You are at the parts counter at the hardware store desperately pantomiming and circumlocuting, begging for the long rubber thingummybob that keeps the soapy water from getting all over the floor. If only you had remembered it is called a gasket! Necessity is the mother of vocabu­lary. Most people learn what ram means when they first discover they need more of it. The trick to mastering computer jargon is first to master the computer. As the widgets and rituals become second nature, they turn into mental pegs upon which to hang the words. Of course the hackers and man­ual writers have a responsibility too: to pick metaphors that keep the lingo both trans­parent and concise and allow lusers to get work done needing as little of it as possible.

And what about the English lan­guage? Like it or not, dozens of computer-inspired words have been co-opted into everyday conversation and writing: bells and whistles, bootstrap, debug, flame (ful­minate self-righteously), hack, hardwired, interactive, kluge (a clumsy but service­able solution), real time, snail-mail, soft­ware, time-sharing and virtual (simulated). Language lovers, relax; this is what the hackers would call a Good Thing.

For centuries English has been snarfing up the jargon of various cliques, cults, guilds and subcultures. The dictionary has thou­sands of examples: countdown and blast-off from the space program, souped-up and shift gears from the automobile, trip and freak out from drug users, boogie and jam from jazz, and so on. Go back even further, and you find that thousands of currently unexceptionable words were at one time denounced as corruptions— sham, banter, mob, stingy and fun, for example. In fact, when you think about it, where else could words come from but slang? Not from some committee! The breathtaking half-a-mil-lion-word vocabulary of English is built from the grass-roots contributions of count­less slang slingers and jargon mongers.

If you ever find yourself longing for a language with a more orderly admissions procedure, I give you French. They have had the Academie Francaise and the Gen­eral Delegation of the French Language and the High Council of the French Lan­guage and the Francophone High Council all charged with keeping the language "pure" (sometimes with the authority to levy fines and jail sentences).Originally concerned with finding replacements for le cheeseburger and le weekend, the com­mittees have become increasingly anxious about imported computer jargon. Com­puter, software, data processing, kit, video clip and buffer have been deemed linguis­tically incorrect; les hackers of the world of informatique must use ordinateur, logiciel, traitement des donnees, kit pret a monter, bande video promotionelle and memoire tampon.

Where has it got them? Their own technology commission estimated that using the French words increases the length of a document 20%. And English has been estimated to contain three to six times as many words as French. Some might say cen­turies of guarding the purity of the French language have left it with verbose expres­sions and a puny vocabulary. But then what can you expect from a bunch of suits?

9. Read and discuss the article. Do you believe that the future is fuzzy? Explain your opinion, referring to scientific journals.

SMART MACHINES

Pop a snack into a fuzzy microwave oven, leave the room and just forget about it.
No, your treat won't come out half raw or burnt to a crisp..Fuzzy microwaves cook foods perfectly all by themselves. And no, they're not covered with fuzz. Fuzzy refers to the fuzzy logic computer chip inside the oven. This chip turns an ordinarily dumb machine into one smart cookie.

Not Just Microwaves Fuzzy logic is spiffy technology that can make almost any machine work better.

Fuzzy washing machines automatically know how much soap and water to add to a load of laundry. They stop washing as soon as the clothes are clean.

Fuzzy, automobiles adjust themselves to fit driving conditions. This saves gas and gives a better ride.

Fuzzy cameras adjust themselves so even a beginner can take good pictures, with every photograph in focus. Fuzzy video cameras remove the jiggle.

It's a technology that will change forever the way we deal with machines.

FUZZY LOGIC

"When Theseus returned from slaying the Minotaur, says Plutarch, the Athenians preserved his ship, and as planks rotted, replaced them with new ones. When the first plank was replaced, everyone agreed it was still the same ship. Adding a second plank made no difference either. At some point, the Athenians may have replaced every plank in the ship. Was it a different ship? At what point did it become one?"

Questions of the above nature, bothered people acquainted with a classical logic for ages. The Aristotelian concept of the excluded middle, where every logical preposition has to either be completely true or false, does not seem to fulfill expectations of nowadays very technical and logic dependent world. Nevertheless, most computer, control system engineers and many other people involved in modeling and programing behavior still rely on the True/False conditions and differential equations. There were several people who tried to adjust classical logic to accept a broader concept of something being true or false. In the early 1900's, Lukasiewicz presented his three-valued logic, where the third value proposed could be described as "possible", and had a numeric value between True and False. His efforts were followed by Knuth, but none of the notions gained a wide acceptance. It was not until 1965, when Lotfi Zadeh published his works on fuzzy sets and math accompanying them. The theory quickly was branded fuzzy logic. It created a lot of new possibilities along with controversy and misunderstandings. This paper attempts to give a general description of the concepts of fuzzy logic and applications that might benefit from it.

The classical logic relies on something being either True or False. A True element is usually assigned a value of 1, while False has a value of 0. Thus, something either completely belongs to a set or it is completely excluded from it. The fuzzy logic broadens this definition of membership. The basis of the logic are fuzzy sets. Unlike in "crisp" sets, where membership is full or none, an object is allowed to belong only partly to one set. The membership of an object to a particular set is described by a real value from the range between 0 and 1. Thus, for instance, an element can have a membership value 0.5, which describes a 50% membership in a given set. Such logic allows a much easier application of many problems that cannot be easily implemented using classical approach.

For example, considering a set of tall people in the classical logic, one has to decide where is the border between the tall people and people that are not tall. If the border is set to ex. 6 feet, than, if the person is 6 feet and 1 inch tall, it belongs to the set of tall people. If the person is 5 feet 11 inches tall it does not belong to the set. In this case such a representation of reality leaves much to be desired. On the other hand, using the fuzzy logic, the person being 6-1 tall can still have a full membership of the set of tall people, but the person that is 5-11 tall, can have 90% membership of the set. The 5-11 person thus can have, what can be described as a "quite tall" representation in a model.

Such a classification certainly allows a single object to be a member of two mutually exclusive in the "crisp" sense sets. For example a person 5 feet and 5 inches tall can be classified as 0.5 tall and also 0.3 short, thus it could be described as "rather tall" and at the same time "sort of short". A single element membership to different sets does not have to add up to any particular value. Although, a membership to a negative set (ex. a set of not tall people) has to equal to 1 minus membership to the positive set (a set of tall people).

Because of the above alterations, some logical operations had to be also modified. For the union of two sets, it was found, the result is the higher membership value out of the two. For example if an element is a person that is 0.6 member of a set of smart people and 0.7 member of a set of pretty people, it makes logical sense to state that such person has 0.7 membership in a set of smart or pretty people. The intersection of the two sets is the minimal element of the operators. Thus, referring to the above example, the person would be only 0.6 member of a set of smart and pretty people.

It is worth noting that such a representation operates on different principles than probabilistic theory, which relies on the same set of values, and is often confused with the fuzzy set manipulation. Unlike as in the fuzzy sets, where an element is partly a member of a set, the probability value describes a chance of the whole element belonging to a particular set. The union and the intersection are the most obvious differences between these two representations. In the case of the fuzzy logic adding memberships for the union of sets or multiplying memberships for the intersection makes no logical sense (ex. a person from the example being 1.3 member of a set of smart or pretty people or 0.42 member of a set of smart and pretty people).

Fuzzy logic since its beginnings stirred a lot of controversy in the United States. Although it is a reliable and consistent source of modeling reality, it is not easily representable in the form of differential equations, most control engineers nowadays have learned to rely on. The name itself became a controversy on the American market. Some people argued that it is too "fuzzy" and too unpredictable. While the States stalled in the controversy, there were thousands of successful fuzzy logic implementations performed in Japan. It is suspected that Japanese culture, which bases on the philosophy that there is no absolute good or absolute evil, had no objections to the concept of partial memberships to different groups. Thus, a lot of Japanese firms applied fuzzy logic concepts to factory and industry control systems, medical and navigational equipment, home electronics, and many more.

One of the most successful fuzzy logic implementations is the control of subway in Sendai, Japan. The fuzzy system controls acceleration, deceleration, and breaking of the train. Since its introduction, it not only reduced energy consumption by 10%, but the passengers hardly notice «now when the train is changing its velocity. In the past neither conventional, nor human control could have achieved such performance.

Generally the fuzzy logic is recommended for the implementation of a very complex processes, where a simple mathematical model cannot be obtained. Fuzzy logic can also be successfully applied to a highly nonlinear processes, where it is observed to greatly simplify the modeling. It is not recommended to employ fuzzy logic into systems where a simple and adequate mathematical model already exists or where the conventional control theory yields a satisfying result. Fuzzy logic seems to be a general case for the classical logic and as such it does not present any better solutions for problems that might be easily solved using the "crisp" sets.

The most obvious implementation for the fuzzy logic is the field of artificial intelligence. In the examples stated at the beginning of this paper it was shown how one can easily relate logic to ambiguous linguistics in form of "very", "little", "sort of, and so on. Such flexibility allows for a rapid advancements and easier implementation of projects in the field of natural language recognition. Although, fuzzy logic not only brings logic closer to natural language, but also closer to human or "natural" reasoning. Many times knowledge engineers have to deal with very vague and common sense descriptions of the reasoning leading to a desired solution. The power of fuzzy logic is to perform reasonable and meaningful operations on concepts that cannot be easily codified using a classical approach. Implementing the logic will not only make the knowledge systems more user friendly, but it also will allow programs to justify better the obtained results.

Fuzzy logic seems to be a general case for the classical logic. It modifies the rules for a set membership and defines operations on modified sets. It allows an element to belong only partly to a given set. Such modification allows for a much more flexible and wide spread use of reliable and consistent logic in a variety of applications. So far, the most common use of the fuzzy logic was encountered in the field of control systems, although the theory seems to have a big potential in the different fields of artificial intelligence. The logic stirred a lot of controversy since its introduction, but as it is successfully implemented into more and more applications, it becomes a more accepted way of modeling reality.

10. Read the information on viruses.

ABOUT VIRUSES, WORMS & TROJANS.

What is a Computer Virus? A computer virus is a program that requires a host in order to make copies of itself on computer disks. Viruses may infect (copy to, and spread from), program files, programs in disk sectors, and files that use macros. The ability to self-replicate distinguishes viruses from programs that do not, and this parasitic nature is neither an accident, nor a computer glitch. All viruses are created by people who know how to write computer programs.

Why are they Called Viruses? The first theories about the possibility of creating a self-replicating program date back to 1949, and experimental viruses were first programmed and tested in the 1960s. They got their name in 1984, when a university professor used the term "virus" to describe them, because like a biological virus, a computer virus is small, makes copies of itself, and cannot exist without a host. When personal computers became popular, PC viruses began to appear (in 1986-1987), at first intended as jokes, or developed for research or demonstration purposes.

What is a Computer Worm? As intranets and the Internet have grown in popularity, e-mail has evolved from a convenience to a necessity. Virus vandals know that, and they've invented new ways to use e-mail to spread viruses, and especially, worms. A worm program is similar to a virus. It is considered by some to be a subset of a virus in that it makes copies of itself but does so without needing to modify a host. Like viruses, worms may (or may not) do things other than replicate.

What is a Trojan horse? Trojan horse programs are named for the giant wooden horse that concealed Greek soldiers who used it to invade the ancient city of Troy. Like that famous trick, a Trojan horse program conceals hidden programming. The hidden function may just be a joke, or something annoying, but vandals often use Trojan horse programs to destroy other people's data, knowing that some people will run any program that

has an interesting file name, or promises to perform a useful function.

Are all these programs harmful? They waste disk space and memory, delay computer operations, and increase the likelihood of system crashes. They are often poorly written and may function erratically, overwrite data, and cause programs to run erratically. Many also have destructive routines to alter or overwrite data. In addition, the cost of antivirus software and the time recovering from virus damage is passed along to consumers by businesses at the cash register.

Who creates these programs - and why? Virus writers range from researchers, to pranksters, to malicious vandals. The typical virus writer is an otherwise intelligent male, between 15 and 23 years old. He may be bored, curious, or intent on doing forbidden things, just to frighten others. Some belong to organized virus-writing groups (usually short­lived), and those in the group often respond to peer pressure, trying to outdo the others. Whether in a group or not, some get satisfaction from the challenge, while others think of themselves as rebels against the "system."

How do they spread? Viruses and Trojans spread from one computer to another by using one or more methods, all of which depend on user carelessness. Some people never have a problem, but others who are not as careful (or lucky) infect their hard disk by running downloaded files, or after placing a newly-obtained floppy disk in a drive. Viruses and worms spread fastest among computers networked on a LAN, especially when e-mail file attachments are involved.

Is sharing files a problem? Sharing certain types of files with others always involves some certain risk. The medium is irrelevant; files from a LAN server, downloaded from Internet sites, from a floppy (even from shrink-wrapped software). Riskiest of all are files posted on Internet newsgroups, because there is no control or accountability. Many people have become the first victims of brand-new viruses and worms, by downloading executable files that were posted deliberately by vandals.

What about e-mail? Before the growth of the Internet, viruses used to spread more slowly, from user to user, and anti-virus vendors were usually able to distribute a remedy before things got out of hand. That's all changed, especially with worms, because some people will click on any e-mailed file that they receive. Vandals have seized their opportunity, and created programs designed to spread to all those who correspond with careless users. Because of this threat, the only 100 percent safe e-mail file attachment is a deleted e-mail file attachment.

Can cookie contain a virus? Some Web sites store information on your computer, in small text files called cookies, that can be used when you re-visit that site. Examples include items you've "selected for purchase, registration data, or your user name and password, for Web sites that require them. Since cookies are text files, they are not executable, and this fact eliminates the possibility of viruses, because they must be hosted by an executable file. It is theoretically possible to include UUencoded or MIME comments, but decoding a UUencoded or MIME file and executing it is not possible.

Do you need to worry?

Worrying will get you nowhere. Instead, take sensible precautions, to avoid losing data should you be affected by a program that was designed to cause problems. Many people are fortunate never to encounter one, but a vandal's program could be concealed in the next file you download, or in a file attached to an e-mail message. Or the threat could be on the next floppy you insert in a disk drive, especially one obtained from a friend, a co-worker, or a fellow student.

How can you tell whether your computer is infected?

Because some viruses cause strange things to happen, an odd or unexplained event may lead a user to conclude a virus must be responsible, without bothering to explore other possible causes. On the other hand, many viruses are carefully programmed to do nothing to betray their presence. The solution to this dilemma is not to assume anything, but to rely upon anti-virus software as a diagnostic tool.

How can you protect your data?

If you have files you can't afford to lose, make sure you have more than one copy of them. Programs may already be backed up on their original installation disks, but what about the files that you create? Business records, spreadsheets, manuscripts, and other important files can be lost in an instant to a virus, or to other causes, hard disk failure among them. If no other copy of your files exists, make copies of them, before it's too late.

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