01-04-2020-Орловская И.В., Самсонова Л.С. Учебник английского языка для технических университетов и вузов (6-е издание, 2006)(1) (1171846), страница 59
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In the car industry CAD software is used todevelop, model and test car designs before the actual parts aremade. This can save a lot of time and money.Basically, computer graphics help users to understand complexinformation quickly by presenting it in more understandable andclearer visual forms. Electric engineers use computer graphics fordesigning circuits and in business it is possible to present information as graphics and diagrams.
These are certain to be much moreeffective ways of communicating than lists of figures or long explanations.Today, three-dimensional graphics along with colour and computer animation are supposed to be essential for graphic design,computer-aided engineering (CAE) and academic research. Computer animation is the process of creating objects and pictureswhich move across the screen; it is used by scientists and engineersto analyze problems. With appropriate software they can study thestructure of objects and how it is affected by particular changes.275А graphic package is the software that enables the user to drawand manipulate objects on a computer. Each graphic package hasits own facilities, as well as a wide range of basic drawing and painting tools. The collection of tools in a package is known as a palette.The basic geometric shapes, such as lines between two points, arcs,circles, polygons, ellipses and even text, making graphical objectsare called «primitives».
You can choose both the primitive you wantand where it should go on the screen. Moreover, you can specify the«attributes» of each primitive, e.g., its colour, line type and so on.The various tools in a palette usually appear together as pop-upicons in a menu. To use one you can activate it by clicking on it.After specifying the primitives and their attributes you musttransform them. Transformation means moving or manipulatingthe object by translating, rotating and scaling the object.Translation is moving an object along an axis to somewhere elsein the viewing area.
Rotation is turning the object larger or smallerin any of the horizontal, vertical or depth direction (correspondingto the X, у and z axis). The term «rendering» describes the techniques used to make your object look real. Rendering includes hidden surface removal, light sources and reflections.To be read after Lesson 12The Space AgeRussia was the first nation into space and is recognized as theworld's leader in building space stations and conducting longduration space missions.
Since Yury Gagarin's epic flight Russianspace science and engineering have come a long way. Space technology remains Russia's deepest source of pride (гордость). Russiahas launched a great number of space vehicles designed to performa variety of functions. Unmanned satellites have been of great significance in the exploration and peaceful use of outer space.
Theyhelp us learn more about the relations between processes occurringon the sun and near the earth and study the structure of the upperatmosphere. These satellites are provided with scientific equipmentfor space navigation of civil aviation and ships, as well as exploration of the World Ocean, the earth's surface and its natural resources.In April 1971, history's first space station, Salyut 1, waslaunched and over the next 15 years six its subsequent versions operated in space. Many orbital manned flights were performed276aboard these stations involving a lot of cosmonauts, most of themhaving flown several times.
Russian cosmonauts are known to holdthe record for the longest time in space (L. Kizim has worked 375days) and for continuous stay in space (V. Titov and M. Manarov —365 days, i.e. a year). The knowledge of Russian doctors and researchers about the medical and psychological consequences oflongterm space flight far exceed that of American scientists. In1973, two years after Salyut 1, the United States launched Skylab,the Western World's first space station which was used for threehighly successful missions. All these manned missions paved theway for even longer stays aboard the Russian Mir space station and,then, aboard the International Space Station.The most successful Mir space station was launched in February 1986. It was expected to have a lifetime of only five years but ithad been in orbit for 15 years before its controlled re-entry into theatmosphere. This space station was equipped with an astronomicalobservatory module named Kwant.
It incoфorated all the noveltythat could be offered by designers and engineers. To keep productivity high, Russian designers paid much attention to the space station livability. The interior of Mir was painted in two colours toprovide the crew with a sense of floor and ceiling. On Mir cosmonauts got two days off each week and had a special radio so thatthey could talk to their families and with any sportsman, scientistor celebrity they wanted.With the twin Vega space probes being successfully launched in1986, Russian scientists conducted close-range studies of Halley'scomet and gathered impressive scientific data about Venus.
Vega 1and Vega 2 carrying more than 30 research instruments passedwithin 10,000 kilometers of the comet's heart, transmitted highquality pictures to Earth and revealed for the first time the dimensions and dynamics of its ten-mile-long nucleus. The relative speedof approaching the comet was equal to 78 km/sec. It should bepointed out that the study of Halley's comet was conducted on thebasis of extensive cooperation of scientists. Scientists from ninecountries, including the U.S, joined the Vega project.When the 170-million horse power launch vehicle called«Energia» was successfully tested in 1987, Russia has gone farahead of the United States in the space race. With the newmulti-purpose Energia rocket it became possible to put into orbit a100-ton payload (one must know that the first satellite carried83,6 kg).The first International Space Station components, Zarya andUnity, have opened a new era of space exploration.
The three-stage277Russian Proton booster was used to launch the Zarya module. Therocket was designed by the Salyut Design Bureau and is manufactured by the Khrunichev State Research and Production SpaceCentre in Moscow. The Proton is among the most reliableheavy-lift launch vehicles in operation with its reliability ratingabout 98 per cent. Proton measures about 180 feet tall, 24 feet indiameter at its widest point and weighs about 1,540,000 poundswhen fully fueled for launch.
The engines use nitrogen tetroxide, anoxidizer, and dimethyl hydrazine, a fuel, as propellants. The firststage includes six engines providing about 1.9 million pounds ofthrust at launch. Four engines creating 475,000 pounds of thrustpower the Proton's second stage. The Proton's third and final stageis powered by a single engine that creates 125,000 pounds of thrust.Assembling the station will be unprecedented task, turning theEarth orbit into a constantly-changing construction site.
Morethan 100 elements will be joined over the course of 45 assemblyflights using the Space Shuttle and two types of Russian rockets. Aninternational team of astronauts and cosmonauts will do much ofthe work by hand, performing more space works in just five yearsthan have been conducted throughout the history of space flight.They will be assisted by a new generation of robotic arms, handsand perhaps even free-flying robotic «eyes».The international partners, Canada, Japan, the EuropeanSpace Agency, are supposed to contribute the following key elements to the ISS: Canada is to provide a robotic arm to be used forassembly and maintenance tasks on the station.
The EuropeanSpace Agency is building a pressurized laboratory to be launchedon the Space Shuttle. Japan is building a laboratory module with anattached platform where experiments can be exposed to space aswell as logistics transport vehicles.Scientists believe the ISS to be the most advanced base for developing technologies, systems and procedures to enable safe, efficient and permanent human presence in space.CryptographyFrom e-mail to cellular communications, from secure Web access to digital money, cryptography is an essential part of today'sinformation systems. The only way to protect a message is to encode it with some form of encryption.
Data encryption is very important for network security, particularly when sending confidentialinformation. Encryption is the process of encoding data so that unauthorized users can't read it. Decryption is the process of decod278ing encrypted data transmitted to you. The most common methodsof protection are passwords for access control, encryption and decryption systems, and firewalls. Firewall is a software and hardwaredevice that allows limited access to an internal network from theInternet.Cryptography helps provide accuracy and confidentiality. Itcan prove your identity or protect your anonymity.
It can preventvandals from changing your Web page and industrial competitorsfrom reading your confidential documents. And in the future, ascommerce and communications continue to move to computernetworks, cryptography will become more and more vital.But the cryptography now on the market does not provide thelevel of security it advertised. Most systems are not designed andimplemented together with cryptographers. Present-day computersecurity is a house of cards; it may stand for now, but it can't last.Electronic vandalism is an increasingly serious problem.
Computervandals take advantage of technologies newer than the system theyattack, using techniques the designers never thought of and eveninvent new mathematics to attack the system with.No one can guarantee 100 % security. But we can work toward100 % risk acceptance. Fraud (обман) exists in current commercesystems. Yet these systems are still successful, because the benefitsand conveniences are greater than the losses. Some systems are notperfect, but they are often good enough.
A good cryptographic system provides a balance between what possible and what is acceptable.The good news about cryptography is that we already have thealgorithms and protocols we need to secure our systems. The badnews is that that was the easy part; implementing the protocols successfully requires considerable expertise. Thus, there is an enormous difference between a mathematic algorithm and its concreteimplementation in hardware and software.Design work is the main support of the science of cryptographyand it is very specialized.
Cryptography combines several areas ofmathematics: number theory, complexity theory, information theory, probability theory, abstract algebra, and formal analysis,among others. Unfortunately, few can do the science properly, anda little knowledge is a dangerous thing: inexperienced cryptographers almost always design imperfect systems. Quality systems usepublished and well-understood algorithms and protocols. Besides,only when cryptography is designed with careful consideration ofusers' needs and then integrated, can it protect their systems, resources, and data.279КРАТКИЙ ПОУРОЧНЫЙ ГРАММАТИЧЕСКИЙСПРАВОЧНИКLESSON 1§ 1.
Глагол to beГлагол to be в Present, Past и Future Indefinite (Simple) имеет следующие формы:ЛичноеместоимениеIPastPresentFutureamwasshaU (wm) beiswaswill bearewereshaU (wiU) bearewerewill be1 fhe 1\ she \П^ 1weГ you 11 1 they JВ вопросительной форме глагол to be ставится перед подлежащим:Are they students?Они студенты?Where were you yesterday?Где вы были вчера?В отрицательной форме после глагола to be ставится отрицание not:They are not in the library.Они не в библиотеке.§ 2.
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