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Text 7A Transport for Tomorrow
One thing is certain about the public transport of the future: it must be more efficient than it is today. The time is coming when it will be quicker to fly across the Atlantic to New York than to travel from home to office. The two main problems are: what vehicle shall we use and how can we plan our use of it?
There are already some modern vehicles which are not yet in common use, but which may become a usual means of transport in the future. One of these is the small electric car: we go out into the street, find an empty car, get into it, drive to our destination, get out and leave the car for the next person who comes along. In fact, there may be no need to drive these cars. With an automatic guid ance system for cars being developed, it will be possible for us to se lect our destination just as today we select a telephone number, and our car will move automatically to the address we want.
For long journeys in private cars one can also use an automatic guidance system. Arriving at the motorway, a driver will select the lane1 he wishes to use, switch over to automatic driving, and then relax — dream, read the newspaper, have a meal, flirt with his pas senger — while the car does the work for him. Unbelievable? It is already possible. Just as in many ships and aircraft today we are pi loted automatically for the greater part of the journey, so in the fu ture we can also have this luxury in our own cars.
A decade ago, the only thing electronic on most automobiles was the radio. But at present sophisticated electronics is playing a big part in current automotive research. For example, in every gasoline-powered2 car that General Motors Corporation makes there is a small computer continuously monitoring the exhaust, r The device, about the size of a pack of cigarettes, adjusts the vehi cle carburetor fuel intake3 to get the best fuel economy. Ford cars are equipped with an electronic instrument panel that, among other things4, will calculate how far one can drive on the fuel left in the tank. It will also estimate the time of arrival at destination and tell the driver what speed he has averaged5 since turning on the ignition.
According to specialists these features made possible by micro electronics are only the beginning. Radar may control the brakes to avoid collisions, and a display screen may show the car's position on the road. Recently a radar to be mounted on lorries and cars has been designed in the USA. The radar aerial looks like a third head light placed directly above the bumper. Having summed up the in formation about the speed and distance of various objects ahead, the computer detects all possible dangers and their nature. A third com ponent in the system is a monitor on the instrument panel. The radar only observes objects ahead of the vehicle. It is automatically turned on when the speed exceeds ten miles an hour. The green light on the panel indicates that the system is on. The yellow light warns of sta tionary objects ahead, or something moving slower than the car. The red light and buzzer warn that the speed should go down. Another red light and sound signal make the driver apply the brakes.
A Japanese company is designing a car of a new generation. When completed, the new model will have a lot of unusual charac teristics. The car's four-wheel control system will ensure move ment diagonally and even sideways, like a crab, at right angles to the longitudinal axis. This is especially important when leaving the car in parking places. To help the driver get information while con centrating on the road, the most important data will be projected on the wind screen. A tourist travelling in such a car will not lose his way even in Sahara with its impassable roads: a navigation Earth satellite will indicate the route.
A new ceramic engine has been developed in Japan. Many im portant parts as pistons, pressure rings6, valves and some others have been made of various ceramic materials, piston rings7 made of silicon materials being in many respects better than those of steel. They withstand temperatures up to 1,000 °C. Therefore, the engine does not need a cooling system
Text 8A A New Era for Aircraft
Aviation experts expect that today's aircraft will begin to be re placed with some new form of supersonic transport in a few years time. A 21st century hypersonic aircraft may open a new age of air craft design.
The designers of this country displayed the project of such a su personic passenger liner among the prospective models at one of the latest Aerospace Salon held on the old Le Bourget airfield in Paris. An elongated fuselage with a sharp nose and without a hori zontal stabilizer makes it look more like a rocket. The speed matches the looks. This plane will fly at a speed five to six times above the speed of sound, e.g., it will cover the distance between Tokyo and Moscow in less than two hours. The diameter of the fu selage will be 4 meters and the overall length 100 meters, with the cabin accommodating 300 passengers. The future super planes of such a class will have no windows, but the passengers can enjoy watch ing the panorama of the Earth on the TV monitor at the front of the cabin. They will fly so fast that ordinary aircraft windows would make the structure too weak to withstand the stresses at such a speed. At high velocities the air resistance in the lower atmosphere is so great that the skin is heated to very high temperature. The only way out is to fly higher. Therefore, airliners' routes will mainly lie in the stratosphere.
In general, to build a reliable hypersonic plane one has to over come a whole set of technological and scientific difficulties. Apart from creating highly economical combined engines and heat-insulating materials, designers have to make such an amount of thermodynamic computations that can't be performed without using supercomputers. One of the ways to make planes as economi cal as possible is lightening the aircraft by substituting new com posite materials for conventional metal alloys. Accounting for less than 5 per cent of the overall aircraft weight now, the percentage of composite material parts will exceed 25 per cent in new generation models. An extensive use of new materials combined with better aerodynamics and engines will allow increasing fuel efficiency by one-third.
Because of the extreme temperatures generated by the atmo sphere friction, a hypersonic craft will also require complicated cooling measures. One possibility is using cryogenic fuels, such as liquid hydrogen, as both coolants and propellants. The fuel flow ing through the aircraft's skin would cool the surfaces as it vapor izes before being injected into combustion chamber.
In addition, specialists in many countries are currently working on new propeller engines considered much more economical and less noisy than jets. The only disadvantage is that propeller planes fly slower than jet planes. However, it has recently been announced that specialists succeeded in solving this problem. As a result a ventilator engine with a propeller of ten fibre-glass blades has been built, each being five meters long. It will be mounted in the experi mental passenger plane.
Text 9A
We know little about the ocean yet. The dream of exploring un der the waves is almost as old as seagoing. Legend says that Alexan der the Great submerged himself in a round glass container, and Leonardo da Vinci designed a submersible vehicle in his notebooks centuries before Jules Verne wrote «Twenty Thousand Leagues Un der the Sea». If their dreams had been realized and such a craft had been constructed, mankind would have known about the secrets of Ocean much earlier. However, already during the Swiss National Fair in 1964 a submersible vehicle took thousands of people deep into Lake Geneva.
Not long ago, the crafts that penetrated the ocean depths were almost as primitive as the marine life they watched around them. However, non-military deep sea ships, so-called submersibles, were progressing rapidly. Russian, French, Japanese and American scientists are developing crafts that can submerge deeper, stay lon ger and find out more than earlier apparatuses.
Soon, one of the most advanced crafts, a one passenger sub merging ship, will be tested. It may be able to take explorers and technicians deeper than ever before (up to 3,300 feet) and perform difficult underwater tasks with extreme precision.
This new submersible is essentially a spherical transparent plastic hull1 mounted on a metal platform. It looks like an underwater heli copter and can manoeuvre itself in its water environment with some of the versatility2 of a helicopter due to the use of a cycloid rotor3 instead of conventional marine-propeller screws4. It is expected that this apparatus will move around the ocean like a sports car.
However, the breakthrough5 that will make this particular craft quite different from other manned submersibles is a mechanical hand called the sensory manipulator system6. Miniature video cameras on the «wrist» of the manipulator provide it with vision and microphones enable the submersible to «hear». This manipula tor system is designed to lift up to 120 pounds and will also be able to perform such accurate scientific work as collecting samples of ocean-floor minerals and marine life. When demonstrated, it lifted crystal glasses, drew pictures and wrote with a pen.
Some scientists are trying to develop the world's deepest manned submersible. When completed, it will be capable of sub merging to the depths of 21,000 feet. Its crew will be in a pres sure-resistant titanium-alloy cabin. This craft will be driven by a battery-operated electric motor and will work for up to nine hours. It will record images with colour television and stereo cameras and will collect samples by manipulating two robotic arms.
If such crafts are constructed on a large scale, we shall be able not only to spend our holidays enjoying the underwater life, but also grow and cultivate sea plants, fish and pearls. It will be possible provided scientists, designers and politicians from all over the world join their efforts and solve the most important problems in this field.
Text 10A
Laser
In the «War of Worlds* written before the turn of the last cen tury H. Wells told a fantastic story of how Martians almost invaded our Earth. Their weapon was a mysterious «sword of heat». Today Wells' sword of heat has come to reality in the laser. The name stands for light amplification by stimulated emission of radiation.
Laser, one of the most sophisticated inventions of man, pro duces an intensive beam of light of a very pure single colour. It rep resents the fulfilment of one of the mankind's oldest dreams of technology to provide1 a light beam intensive enough to vaporize the hardest and most heat-resistant materials. It can indeed make lead run like water, or, when focused, it can vaporize any substance on the earth. There is no material unamenable2 to laser treatment and laser will become one of the main technological tools quite soon.
The applications of laser in industry and science are so many and so varied as to suggest magic3. Scientists in many countries are working at a very interesting problem: combining the two big tech nological discoveries of the second half of the 20th century — laser and thermonuclear reaction — to produce a practically limitless source of energy. Physicists of this country have developed large la ser installations to conduct physical experiments in heating ther monuclear fuel with laser beams. There also exists an idea to use laser for solving the problem of controlled thermonuclear reaction. The laser beam must heat the fuel to the required temperature so quickly that the plasma does not have time to disintegrate. Accord ing to current estimates, the duration of the pulse has to be approx imately a billionth of a second. The light capacity of this pulse would be dozens of times greater than the capacity of all the world's power plants. To meet such demands in practice, scientists and engineers must work hard as it is clear that a lot of difficulties are to be encountered on route4.
The laser's most important potential may be its use in commu nications. The intensity of a laser can be rapidly changed to encode very complex signals. In principle, one laser beam, vibrating a bil lion times faster than ordinary radio waves, could carry the radio, TV and telephone messages of the world simultaneously. In just a fraction of a second, for example, one laser beam could transmit the entire text of the Encyclopaedia Britannica.
Besides, there are projects to use lasers for long distance com munication and for transmission of energy to space stations, to the surface of the Moon or to planets in the Solar system. Projects have also been suggested to place lasers aboard Earth satellites nearer to the Sun in order to transform the solar radiation into laser beams, with this transformed energy subsequently transmitted to the Earth-or to other space bodies. These projects have not yet been put into effect5, because of the great technological difficulties to be over come and, therefore, the great cost involved. But there is no doubt that in time6 these projects will be realized and the laser beam will begin operating in outer space as well.
Text 11A
Superconductivity
According to the prominent scientist in this country V.L. Ginz-burg the latest world achievements in the field of superconductivity mean a revolution in technology and industry. Recent spectacular breakthroughs1 in superconductors may be compared with the physics discoveries that led to electronics and nuclear power. They are likely to bring the mankind to the threshold of a new technolog ical age. Prestige, economic and military benefits could well come to the nation that first will master this new field of physics. Super conductors were once thought to be physically impossible. But in 1911 superconductivity was discovered by a Dutch physicist K. Onnes, who was awarded the Nobel Prize in 1913 for his low-temperature research. He found the electrical resistivity of a mer cury wire to disappear suddenly when cooled below a temperature of 4 Kelvin (-269 °C). Absolute zero is known to be 0 K. This dis covery was a completely unexpected phenomenon. He also discov ered that a superconducting material can be returned to the normal state either by passing a sufficiently large current through it or by applying a sufficiently strong magnetic field to it. But at that time there was no theory to explain this.
For almost 50 years after K. Onnes' discovery theorists were unable to develop a fundamental theory of superconductivity. In 1950 physicists Landau and Ginzhurg made a great contribution to the development of superconductivity theory. They introduced a model which proved to be useful in understanding electromagnetic properties of superconductors. Finally, in 1957 a satisfactory the ory was presented by American physicists, which won for them in 1972 the Nobel Prize in physics. Research in superconductors be came especially active since a discovery made in 19%6 by IBM2 sci entists in Zurich. They found a metallic ceramic compound to become a superconductor at a temperature well above3 the previ ously achieved record of 23 K.
It was difficult to believe it. However, in 1987 American physi cist Paul Chu informed about a much more sensational discovery: he and his colleagues produced superconductivity at an unbeliev able before temperature 98 K in a special ceramic material. At once in all leading laboratories throughout the world superconductors of critical temperature 100 K and higher (that is, above the boiling temperature of liquid nitrogen) were obtained. Thus, potential technical uses of high temperature superconductivity seemed to be possible and practical. Scientists have found a ceramic material that v/orks at room temperature. But getting superconductors from the laboratory into production will be no easy task. While the new superconductors are easily made, their quality is often uneven. Some tend to break when produced, others lose their superconduc tivity within minutes or hours. All are extremely difficult to fabri cate into wires. Moreover, scientists lack a full understanding of how ceramics become superconductors. This fact makes develop ing new substances largely a random process. This is likely to continue until theorists give a fuller explanation of how supercon ductivity is produced in new materials.
Text 12A
The International Space Station
The International Space Station (ISS), the most complex and expensive structure that has ever been launched and built in space, is expected to be a permanent off-planet extension of human civi lization. When completed, it will be a multi-room hotel and re search facility orbiting the Earth every 90 minutes. By that time, resupply and assembly flight by shuttles or rockets will have be come routine.
The Russians and Americans are partners in this international enterprise. The three-person multi-national crews will be alter nately composed of two Americans and one Russian followed by a Russian majority. Later a six or seven-person crew will occupy the station. Some astronauts may stay on the ISS up to 187 days, but there are no plans yet for longer missions. The official life expec tancy of the station itself is 10 years, but it should last much longer.
Five times the size of the Russian space station Mir, the ISS will be one of the biggest objects in the night sky, looking like a supersize Lego set, almost as long as a football field. Only the Moon and Venus will be bigger and more visible.
The fifth-generation station's complexity is as awesome as its size. Built by a partnership of 16 nations, the ISS will consist of 36 modules and hundreds of individual elements that come from all over the world. The station involves the most technologically ad vanced nations — Russia, the United States, Canada, Japan, Brazil, and 11 European nations. There will be many intercon nected parts from so many countries that it would be impossible to predict how they would interact.
Hence, it is very important that all of these elements made by different suppliers should fit together properly and work exactly as planned. But even if all the parts fitted perfectly, the assembly pro cess itself in orbit would be risky. The space station is flown while it is being constructed and each new building block added might change the way the station behaves in flight, which could result in serious trouble.
The ISS may be the world's most ambitious engineering project in history, but it could not have been realized without previous ex tensive experience in operating the Russian Mir space station. Mir was a/great achievement. Russia learned how to build and maintain complex structures in space. Mir also gave citizens of more than a dozen countries their first opportunity to explore space. It should be noted that Mir has proved to be the perfect training ground for the ISS. For more than a decade, at least two humans were always in low Earth orbit. That is why it was planned that Russia would supply and deliver 12 modules for the future station, each being a key module among its 36 ones. They are: the basic power module, the control, the life support, the service modules and others.
What is the purpose of the ISS? It is a political program as well as a science program. This program is no longer only about con ducting scientific investigations in the absence of gravity, or about learning how to build a massive project weighing 400 tons in orbit, or about establishing the base for a future trip to Mars. The ISS is more than merely the next great adventure of the space age. It is also about promoting international cooperation and creating thou sands of peacetime jobs for highly skilled workers and engineers.
The implementation of the broad international program would require more than $40 billion. Some space experts would like to at tract commercial users such as, e.g., biotechnology companies in order that the cost of the station should be lowered. And some spe cialists have even suggested that the station be used for advertising and Hollywood filmmaking.