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61 положительный
1) ( утвердительный) affirmative; ( одобрительный) positive [-z-]положи́тельный отве́т — affirmative answer / reply; ( благоприятный) favourable reply / answer
положи́тельное реше́ние вопро́са — positive / favourable solution of the problem
2) (заслуживающий одобрения, полезный) positive, goodположи́тельный приме́р — good example
положи́тельные ка́чества — positive qualities
3) ( обладающий достоинствами - о человеке) good, positiveположи́тельный геро́й — positive character / hero; good guy разг.
4) мат., физ. positiveположи́тельное число́ — positive number
положи́тельный электри́ческий заря́д — positive electric charge
5) разг. (совершенный, полный) complete, absoluteположи́тельный неве́жда — complete ignoramus
••положи́тельная сте́пень сравне́ния грам. — positive degree
положи́тельная реа́кция мед. — positive response
с положи́тельной реа́кцией на ВИЧ — HIV-positive
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62 Economy
Portugal's economy, under the influence of the European Economic Community (EEC), and later with the assistance of the European Union (EU), grew rapidly in 1985-86; through 1992, the average annual growth was 4-5 percent. While such growth rates did not last into the late 1990s, portions of Portugal's society achieved unprecedented prosperity, although poverty remained entrenched. It is important, however, to place this current growth, which includes some not altogether desirable developments, in historical perspective. On at least three occasions in this century, Portugal's economy has experienced severe dislocation and instability: during the turbulent First Republic (1911-25); during the Estado Novo, when the world Depression came into play (1930-39); and during the aftermath of the Revolution of 25 April, 1974. At other periods, and even during the Estado Novo, there were eras of relatively steady growth and development, despite the fact that Portugal's weak economy lagged behind industrialized Western Europe's economies, perhaps more than Prime Minister Antônio de Oliveira Salazar wished to admit to the public or to foreigners.For a number of reasons, Portugal's backward economy underwent considerable growth and development following the beginning of the colonial wars in Africa in early 1961. Recent research findings suggest that, contrary to the "stagnation thesis" that states that the Estado Novo economy during the last 14 years of its existence experienced little or no growth, there were important changes, policy shifts, structural evolution, and impressive growth rates. In fact, the average annual gross domestic product (GDP) growth rate (1961-74) was about 7 percent. The war in Africa was one significant factor in the post-1961 economic changes. The new costs of finance and spending on the military and police actions in the African and Asian empires in 1961 and thereafter forced changes in economic policy.Starting in 1963-64, the relatively closed economy was opened up to foreign investment, and Lisbon began to use deficit financing and more borrowing at home and abroad. Increased foreign investment, residence, and technical and military assistance also had effects on economic growth and development. Salazar's government moved toward greater trade and integration with various international bodies by signing agreements with the European Free Trade Association and several international finance groups. New multinational corporations began to operate in the country, along with foreign-based banks. Meanwhile, foreign tourism increased massively from the early 1960s on, and the tourism industry experienced unprecedented expansion. By 1973-74, Portugal received more than 8 million tourists annually for the first time.Under Prime Minister Marcello Caetano, other important economic changes occurred. High annual economic growth rates continued until the world energy crisis inflation and a recession hit Portugal in 1973. Caetano's system, through new development plans, modernized aspects of the agricultural, industrial, and service sectors and linked reform in education with plans for social change. It also introduced cadres of forward-looking technocrats at various levels. The general motto of Caetano's version of the Estado Novo was "Evolution with Continuity," but he was unable to solve the key problems, which were more political and social than economic. As the boom period went "bust" in 1973-74, and growth slowed greatly, it became clear that Caetano and his governing circle had no way out of the African wars and could find no easy compromise solution to the need to democratize Portugal's restive society. The economic background of the Revolution of 25 April 1974 was a severe energy shortage caused by the world energy crisis and Arab oil boycott, as well as high general inflation, increasing debts from the African wars, and a weakening currency. While the regime prescribed greater Portuguese investment in Africa, in fact Portuguese businesses were increasingly investing outside of the escudo area in Western Europe and the United States.During the two years of political and social turmoil following the Revolution of 25 April 1974, the economy weakened. Production, income, reserves, and annual growth fell drastically during 1974-76. Amidst labor-management conflict, there was a burst of strikes, and income and productivity plummeted. Ironically, one factor that cushioned the economic impact of the revolution was the significant gold reserve supply that the Estado Novo had accumulated, principally during Salazar's years. Another factor was emigration from Portugal and the former colonies in Africa, which to a degree reduced pressures for employment. The sudden infusion of more than 600,000 refugees from Africa did increase the unemployment rate, which in 1975 was 10-15 percent. But, by 1990, the unemployment rate was down to about 5-6 percent.After 1985, Portugal's economy experienced high growth rates again, which averaged 4-5 percent through 1992. Substantial economic assistance from the EEC and individual countries such as the United States, as well as the political stability and administrative continuity that derived from majority Social Democratic Party (PSD) governments starting in mid-1987, supported new growth and development in the EEC's second poorest country. With rapid infrastruc-tural change and some unregulated development, Portugal's leaders harbored a justifiable concern that a fragile environment and ecology were under new, unacceptable pressures. Among other improvements in the standard of living since 1974 was an increase in per capita income. By 1991, the average minimum monthly wage was about 40,000 escudos, and per capita income was about $5,000 per annum. By the end of the 20th century, despite continuing poverty at several levels in Portugal, Portugal's economy had made significant progress. In the space of 15 years, Portugal had halved the large gap in living standards between itself and the remainder of the EU. For example, when Portugal joined the EU in 1986, its GDP, in terms of purchasing power-parity, was only 53 percent of the EU average. By 2000, Portugal's GDP had reached 75 percent of the EU average, a considerable achievement. Whether Portugal could narrow this gap even further in a reasonable amount of time remained a sensitive question in Lisbon. Besides structural poverty and the fact that, in 2006, the EU largesse in structural funds (loans and grants) virtually ceased, a major challenge for Portugal's economy will be to reduce the size of the public sector (about 50 percent of GDP is in the central government) to increase productivity, attract outside investment, and diversify the economy. For Portugal's economic planners, the 21st century promises to be challenging. -
63 Bayesian theory
Statsa statistical theory and method for drawing conclusions about the future occurrence of a given parameter of a statistical distribution by calculating from prior data on its frequency of occurrence. The theory is useful in the solution of theoretical and applied problems in science, industry, and government, for example, in econometrics and finance. -
64 Daguerre, Louis Jacques Mandé
SUBJECT AREA: Photography, film and optics[br]b. 18 November 1787 Carmeilles-en-Parisis, Franced. 10 July 1851 Petit-Bry-sur-Marne, France[br]French inventor of the first practicable photographic process.[br]The son of a minor official in a magistrate's court, Daguerre showed an early aptitude for drawing. He was first apprenticed to an architect, but in 1804 he moved to Paris to learn the art of stage design. He was particularly interested in perspective and lighting, and later showed great ingenuity in lighting stage sets. Fascinated by a popular form of entertainment of the period, the panorama, he went on to create a variant of it called the diorama. It is assumed that he used a camera obscura for perspective drawings and, by purchasing it from the optician Chevalier, he made contact with Joseph Nicéphore Niepce. In 1829 Niepce and Daguerre entered into a formal partnership to perfect Niepce's heliographic process, but the partnership was dissolved when Niepce died in 1833, when only limited progress had been made. Daguerre continued experimenting alone, however, using iodine and silver plates; by 1837 he had discovered that images formed in the camera obscura could be developed by mercury vapour and fixed with a hot salt solution. After unsuccessfully attempting to sell his process, Daguerre approached F.J.D. Arago, of the Académie des Sciences, who announced the discovery in 1839. Details of Daguerre's work were not published until August of that year when the process was presented free to the world, except England. With considerable business acumen, Daguerre had quietly patented the process through an agent, Miles Berry, in London a few days earlier. He also granted a monopoly to make and sell his camera to a Monsieur Giroux, a stationer by trade who happened to be a relation of Daguerre's wife. The daguerreotype process caused a sensation when announced. Daguerre was granted a pension by a grateful government and honours were showered upon him all over the world. It was a direct positive process on silvered copper plates and, in fact, proved to be a technological dead end. The future was to lie with negative-positive photography devised by Daguerre's British contemporary, W.H.F. Talbot, although Daguerre's was the first practicable photographic process to be announced. It captured the public's imagination and in an improved form was to dominate professional photographic practice for more than a decade.[br]Principal Honours and DistinctionsOfficier de la Légion d'honneur 1839. Honorary FRS 1839. Honorary Fellow of the National Academy of Design, New York, 1839. Honorary Fellow of the Vienna Academy 1843. Pour le Mérite, bestowed by Frederick William IV of Prussia, 1843.Bibliography14 August 1839, British patent no. 8,194 (daguerrotype photographic process).The announcement and details of Daguerre's invention were published in both serious and popular English journals. See, for example, 1839 publications of Athenaeum, Literary Gazette, Magazine of Science and Mechanics Magazine.Further ReadingH.Gernsheim and A.Gernsheim, 1956, L.J.M. Daguerre (the standard account of Daguerre's work).—1969, The History of Photography, rev. edn, London (a very full account).J.M.Eder, 1945, History of Photography, trans. E. Epstean, New York (a very full account).JWBiographical history of technology > Daguerre, Louis Jacques Mandé
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65 Harrison, John
[br]b. 24 March 1693 Foulby, Yorkshire, Englandd. 24 March 1776 London, England[br]English horologist who constructed the first timekeeper of sufficient accuracy to determine longitude at sea and invented the gridiron pendulum for temperature compensation.[br]John Harrison was the son of a carpenter and was brought up to that trade. He was largely self-taught and learned mechanics from a copy of Nicholas Saunderson's lectures that had been lent to him. With the assistance of his younger brother, James, he built a series of unconventional clocks, mainly of wood. He was always concerned to reduce friction, without using oil, and this influenced the design of his "grasshopper" escapement. He also invented the "gridiron" compensation pendulum, which depended on the differential expansion of brass and steel. The excellent performance of his regulator clocks, which incorporated these devices, convinced him that they could also be used in a sea dock to compete for the longitude prize. In 1714 the Government had offered a prize of £20,000 for a method of determining longitude at sea to within half a degree after a voyage to the West Indies. In theory the longitude could be found by carrying an accurate timepiece that would indicate the time at a known longitude, but the requirements of the Act were very exacting. The timepiece would have to have a cumulative error of no more than two minutes after a voyage lasting six weeks.In 1730 Harrison went to London with his proposal for a sea clock, supported by examples of his grasshopper escapement and his gridiron pendulum. His proposal received sufficient encouragement and financial support, from George Graham and others, to enable him to return to Barrow and construct his first sea clock, which he completed five years later. This was a large and complicated machine that was made out of brass but retained the wooden wheelwork and the grasshopper escapement of the regulator clocks. The two balances were interlinked to counteract the rolling of the vessel and were controlled by helical springs operating in tension. It was the first timepiece with a balance to have temperature compensation. The effect of temperature change on the timekeeping of a balance is more pronounced than it is for a pendulum, as two effects are involved: the change in the size of the balance; and the change in the elasticity of the balance spring. Harrison compensated for both effects by using a gridiron arrangement to alter the tension in the springs. This timekeeper performed creditably when it was tested on a voyage to Lisbon, and the Board of Longitude agreed to finance improved models. Harrison's second timekeeper dispensed with the use of wood and had the added refinement of a remontoire, but even before it was tested he had embarked on a third machine. The balance of this machine was controlled by a spiral spring whose effective length was altered by a bimetallic strip to compensate for changes in temperature. In 1753 Harrison commissioned a London watchmaker, John Jefferys, to make a watch for his own personal use, with a similar form of temperature compensation and a modified verge escapement that was intended to compensate for the lack of isochronism of the balance spring. The time-keeping of this watch was surprisingly good and Harrison proceeded to build a larger and more sophisticated version, with a remontoire. This timekeeper was completed in 1759 and its performance was so remarkable that Harrison decided to enter it for the longitude prize in place of his third machine. It was tested on two voyages to the West Indies and on both occasions it met the requirements of the Act, but the Board of Longitude withheld half the prize money until they had proof that the timekeeper could be duplicated. Copies were made by Harrison and by Larcum Kendall, but the Board still continued to prevaricate and Harrison received the full amount of the prize in 1773 only after George III had intervened on his behalf.Although Harrison had shown that it was possible to construct a timepiece of sufficient accuracy to determine longitude at sea, his solution was too complex and costly to be produced in quantity. It had, for example, taken Larcum Kendall two years to produce his copy of Harrison's fourth timekeeper, but Harrison had overcome the psychological barrier and opened the door for others to produce chronometers in quantity at an affordable price. This was achieved before the end of the century by Arnold and Earnshaw, but they used an entirely different design that owed more to Le Roy than it did to Harrison and which only retained Harrison's maintaining power.[br]Principal Honours and DistinctionsRoyal Society Copley Medal 1749.Bibliography1767, The Principles of Mr Harrison's Time-keeper, with Plates of the Same, London. 1767, Remarks on a Pamphlet Lately Published by the Rev. Mr Maskelyne Under theAuthority of the Board of Longitude, London.1775, A Description Concerning Such Mechanisms as Will Afford a Nice or True Mensuration of Time, London.Further ReadingR.T.Gould, 1923, The Marine Chronometer: Its History and Development, London; reprinted 1960, Holland Press.—1978, John Harrison and His Timekeepers, 4th edn, London: National Maritime Museum.H.Quill, 1966, John Harrison, the Man who Found Longitude, London. A.G.Randall, 1989, "The technology of John Harrison's portable timekeepers", Antiquarian Horology 18:145–60, 261–77.J.Betts, 1993, John Harrison London (a good short account of Harrison's work). S.Smiles, 1905, Men of Invention and Industry; London: John Murray, Chapter III. Dictionary of National Biography, Vol. IX, pp. 35–6.DV -
66 Leclanché, Georges
SUBJECT AREA: Electricity[br]b. 1839 Paris, Franced. 14 September 1882 Paris, France[br]French chemist and inventor of the primary cell named after him, from which the electrochemical principles of the modern dry cell have been developed.[br]Leclanché was sent to England for his early education. Returning to France, he entered the Central School of Arts and Manufacture, from which he graduated as a chemical engineer in 1860. He spent some years with a railway company in setting up an electrical timing system, and this work led him to electrochemical research. Driven by political pressure into exile, he set up a small laboratory in Brussels to continue the studies of the behaviour of voltaic cells he had started in France. Many workers directed their efforts to constructing a cell with a single electrolyte and a solid insoluble depo-larizer, but it was Leclanché who produced, in 1866, the prototype of a battery that was rugged, cheap and contained no highly corro-sive liquid. With electrodes of carbon and zinc and a solution of ammonium chloride, polarization was prevented by surrounding the positive electrode with manganese dioxide. The Leclanché cell was adopted by the Belgian Government Telegraph Service in 1868 and rapidly came into general use wherever an intermittent current was needed; for example, in telegraph and later in telephone circuits. Carl Gassner in 1888 pioneered successful dry cells based on the Leclanché system, with the zinc anode serving as the container, and c. 1890 commercial production of such cells began.[br]Bibliography10 October 1866, British patent no. 2,623 (Leclanché cell).1868, "Pile au peroxyde de manganèse à seul liquide", Les Mondes 16:532–3 (describes the Leclanché cell).Further ReadingM.Barak, 1966, "Georges Leclanché (1939–1882)", IEE Electronics and Power 12:184– 91 (a detailed account).N.C.Cahoon and G.W.Heise (eds), 1976, The Primary Battery, Vol. II, New York, pp. 1–147 (describes subsequent developments), GW -
67 Nobel, Alfred Bernhard
[br]b. 21 October 1833 Stockholm, Swedend. 10 December 1896 San Remo, Italy[br]Swedish industrialist, inventor of dynamite, founder of the Nobel Prizes.[br]Alfred's father, Immanuel Nobel, builder, industrialist and inventor, encouraged his sons to follow his example of inventiveness. Alfred's education was interrupted when the family moved to St Petersburg, but was continued privately and was followed by a period of travel. He thus acquired a good knowledge of chemistry and became an excellent linguist.During the Crimean War, Nobel worked for his father's firm in supplying war materials. The cancellation of agreements with the Russian Government at the end of the war bankrupted the firm, but Alfred and his brother Immanuel continued their interest in explosives, working on improved methods of making nitroglycerine. In 1863 Nobel patented his first major invention, a detonator that introduced the principle of detonation by shock, by using a small charge of nitroglycerine in a metal cap with detonating or fulminating mercury. Two years later Nobel set up the world's first nitroglycerine factory in an isolated area outside Stockholm. This led to several other plants and improved methods for making and handling the explosive. Yet Nobel remained aware of the dangers of liquid nitroglycerine, and after many experiments he was able in 1867 to take out a patent for dynamite, a safe, solid and pliable form of nitroglycerine, mixed with kieselguhr. At last, nitroglycerine, discovered by Sobrero in 1847, had been transformed into a useful explosive; Nobel began to promote a worldwide industry for its manufacture. Dynamite still had disadvantages, and Nobel continued his researches until, in 1875, he achieved blasting gelatin, a colloidal solution of nitrocellulose (gun cotton) in nitroglycerine. In many ways it proved to be the ideal explosive, more powerful than nitroglycerine alone, less sensitive to shock and resistant to moisture. It was variously called Nobel's Extra Dynamite, blasting gelatin and gelignite. It immediately went into production.Next, Nobel sought a smokeless powder for military purposes, and in 1887 he obtained a nearly smokeless blasting powder using nitroglycerine and nitrocellulose with 10 per cent camphor. Finally, a progressive, smokeless blasting powder was developed in 1896 at his San Remo laboratory.Nobel's interests went beyond explosives into other areas, such as electrochemistry, optics and biology; his patents amounted to 355 in various countries. However, it was the manufacture of explosives that made him a multimillionaire. At his death he left over £2 million, which he willed to funding awards "to those who during the preceding year, shall have conferred the greatest benefit on mankind".[br]Bibliography1875, On Modern Blasting Agents, Glasgow (his only book).Further ReadingH.Schuck et al., 1962, Nobel, the Man and His Prizes, Amsterdam.E.Bergengren, 1962, Alfred Nobel, the Man and His Work, London and New York (includes a supplement on the prizes and the Nobel institution).LRD -
68 Animal Intelligence
We can... distinguish sharply between the kind of behavior which from the very beginning arises out of a consideration of the structure of a situation, and one that does not. Only in the former case do we speak of insight, and only that behavior of animals definitely appears to us intelligent which takes account from the beginning of the lay of the land, and proceeds to deal with it in a single, continuous, and definite course. Hence follows this criterion of insight: the appearance of a complete solution with reference to the whole lay- out of the field. (KoЁhler, 1927, pp. 169-170)Signs, in [Edward] Tolman's theory, occasion in the rat realization, or cognition, or judgment, or hypotheses, or abstraction, but they do not occasion action. In his concern with what goes on in the rat's mind, Tolman has neglected to predict what the rat will do. So far as the theory is concerned the rat is left buried in thought: if he gets to the food-box at the end that is his concern, not the concern of the theory. (Guthrie, 1972, p. 172)3) A New Insight Consists of a Recombination of Pre-existent Mediating PropertiesThe insightful act is an excellent example of something that is not learned, but still depends on learning. It is not learned, since it can be adequately performed on its first occurrence; it is not perfected through practice in the first place, but appears all at once in recognizable form (further practice, however, may still improve it). On the other hand, the situation must not be completely strange; the animal must have had prior experience with the component parts of the situation, or with other situations that have some similarity to it.... All our evidence thus points to the conclusion that a new insight consists of a recombination of pre existent mediating processes, not the sudden appearance of a wholly new process. (Hebb, 1958, pp. 204-205)In Morgan's own words, the principle is, "In no case may we interpret an action as the outcome of the exercise of a higher psychical faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale." Behaviorists universally adopted this idea as their own, interpreting it as meaning that crediting consciousness to animals can't be justified if the animal's behavior can be explained in any other way, because consciousness is certainly a "higher psychical faculty." Actually, their interpretation is wrong, since Morgan was perfectly happy with the idea of animal consciousness: he even gives examples of it directly taken from dog behavior. Thus in The Limits of Animal Intelligence, he describes a dog returning from a walk "tired" and "hungry" and going down into the kitchen and "looking up wistfully" at the cook. Says Morgan about this, "I, for one, would not feel disposed to question that he has in his mind's eye a more or less definite idea of a bone."Morgan's Canon really applies to situations where the level of intelligence credited to an animal's behavior goes well beyond what is really needed for simple and sensible explanation. Thus application of Morgan's Canon would prevent us from presuming that, when a dog finds its way home after being lost for a day, it must have the ability to read a map, or that, if a dog always begins to act hungry and pace around the kitchen at 6 P.M. and is always fed at 6:30 P.M., this must indicate that it has learned how to tell time. These conclusions involve levels of intelligence that are simply not needed to explain the behaviors. (Coren, 1994, pp. 72-73)Historical dictionary of quotations in cognitive science > Animal Intelligence
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69 НКУ с устройствами ограничения воздействия внутренней дуги
НКУ с устройствами ограничения воздействия внутренней дуги
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[Интент]Параллельные тексты EN-RU
Assemblies equipped with devices limiting internal arc effects (active protection)
A design philosophy which is completely different from that just considered consists in guaranteeing the resistance to internal arcing by installing devices limiting the arc.
The approaches in that direction can be of two different types:
• limiting the destructive effects of the arc, once it has occured, by means of arc detectors
• limiting the destructive effects of the arc, once it has occured, by means of overpressure detectors.
The first possibility consists in installing in the assembly arc detectors which sense the light flux associated with the electric arc phenomenon.
Once the arc has been detected, these devices send an opening signal to the incoming circuit-breaker, thus guaranteeing tripping times of the order of 1-2 ms, therefore shorter than those proper of the circuit-breaker.
The operating logic of an arc detector is the following: the occurrence of an arc inside the switchboard is detected by the arc detector because an intense light radiation is associated with this phenomenon.
The arcing control system detects the event and sends a tripping signal to the circuit-breaker.
All the above with trip times of a few milliseconds and supplanting the tripping of the CB overcurrent relay which, for example, could be delayed due to current selectivity questions.
Figure 1 shows the possible positions where this device can be installed inside a switchboard.
The ideal solution is that which provides the installation of at least one detector for each column, with the consequent reduction to a minimum of the length of the optical fibers carrying the signal.
In order to prevent from an unwanted tripping caused by light sources indepent of the arc (lamps, solar radiation etc.), an additional current sensor is often positioned at the incoming of the main circuit-breaker.
Only in the event of an arc, both the incoming sensor which detects an “anomalous” current due to the arc fault as well as the sensor detecting the light radiation as sociated with the arc enable the system to intervene and allow the consequent opening of the circuit-breaker.
The second possibility consists in installing overpressure sensors inside the switchboard.
As previously described, the overpressure wave is one of the other effects occurring inside an assembly in case of arcing.
As a consequence it is possible to install some pressure sensors which are able to signal the pressure peak associated with the arc ignition with a delay of about 10-15 ms.
The signal operates on the supply circuit-breaker without waiting for the trip times of the selectivity protections to elapse, which are necessarily longer.
Such a system does not need any electronic processing device, since it acts directly on the tripping coil of the supply circuit-breaker.
Obviously it is essential that the device is set at fixed trip thresholds.
When an established internal overpressure is reached, the arc detector intervenes.
However, it is not easy to define in advance the value of overpressure generated by an arc fault inside a switchboard.
[ABB]НКУ с устройствами ограничения воздействия внутренней дуги (активная защита)
Для решения этой задачи используются совершенно другие, отличающиеся от ранее рассмотренных, принципы, заключающиеся в том, что противодействие внутренней дуге обеспечивается применением устройств, ограничивающих саму дугу.
Существует два типа решения проблемы в этом направлении:
• ограничение разрушающего воздействия дуги после того, как ее обнаружат специальные устройства
• ограничение разрушающего воздействия дуги после того, как специальные устройства обнаружат возникновение избыточного давления.
В первом случае в НКУ устанавливают устройства обнаружения дуги, реагирующие на световой поток, сопровождающий явление электрической дуги.
При обнаружении дуги данные устройства посылают сигнал управления на размыкание вводного автоматического выключателя. Гарантируемое время реакции составляет 1-2 мс, что меньше времени срабатывания автоматического выключателя.
Логика работы устройства обнаружения дуги следующая: Дуга, возникшая внутри НКУ, обнаруживается датчиком, реагирующим на интенсивное световое излучение, которым сопровождается горение дуги.
Обнаружив дугу, система управления посылает сигнал автоматическому выключателю.
Время срабатывания датчика и системы управления составляет несколько миллисекунд, что меньше времени срабатывания автоматического выключателя, осуществляющего защиту от сверхтока, который обычно для обеспечения требуемой селективности срабатывает с задержкой.
На рис. 1 показаны места возможной установки устройства защиты внутри НКУ.
Идеальным решением является установка, по крайней мере, одного устройства защиты в каждый шкаф многошкафного НКУ.
Это позволит до минимума сократить длину оптоволоконных кабелей передачи сигнала.
Для предотвращения ложного срабатывания от других источников света (т. е. не от дуги), например, таких как лампы, солнечное излучение и т. п., дополнительно в главной цепи вводного автоматического выключателя устанавливают датчик тока.
Только при наличии двух событий, а именно: срабатывания датчика света и обнаружения аномального увеличения тока, система управления считает, что возникла электрическая дуга и подает команду на отключение вводного автоматического выключателя.
Второе решение заключается в установке внутри НКУ датчика избыточного давления.
Как было описано ранее, одним из характерных проявлений электрической дуги, возникшей внутри НКУ, является ударная волна.
Это означает, что можно установить несколько датчиков давления, задачей которых является обнаружение импульса давления (с задержкой 10…15 мс), обусловленного зажиганием дуги.
Сигнал от датчиков давления поступает на вводной автоматический выключатель, который срабатывает без задержки на обеспечение селективности.
Такая система не нуждается в электронном устройстве обработки информации, поскольку воздействует непосредственно на независимый расцепитель автоматического выключателя.
Вполне понятно, что такое устройство имеет фиксированный порог срабатывания.
Датчик-реле дуги сработает, как только будет достигнуто заданное значение избыточного давления.
Следует иметь в виду, что не так легко заранее определить значение избыточного давления, которое будет создано при зажигании дуги внутри НКУ.
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Русско-английский словарь нормативно-технической терминологии > НКУ с устройствами ограничения воздействия внутренней дуги
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70 постоянный ток
постоянный ток
Электрический ток, не изменяющийся во времени.
Примечание — Аналогично определяют постоянные электрическое напряжение, электродвижущую силу, магнитный поток и т. д.
[ ГОСТ Р 52002-2003]Параллельные тексты EN-RU For definition, the electric current called “direct” has a unidirectional trend constant in time.
As a matter of fact, by analyzing the motion of the charges at a point crossed by a direct current, it results that the quantity of charge (Q) flowing through that point (or better, through that cross section) in each instant is always the same.
[ABB]Постоянным током называется электрический ток, значение и направление которого, не изменяются во времени.
Если рассматривать постоянный ток как прохождение элементарных электрических зарядов через определенную точку, то значение заряда (Q), протекающего через эту точку (а вернее через это поперечное сечение проводника) за единицу времени будет постоянным.
[Перевод Интент]Direct current, which was once the main means of distributing electric power, is still widespread today in the electrical plants supplying particular industrial applications.
The advantages in terms of settings, offered by the employ of d.c. motors and by supply through a single line, make direct current supply a good solution for railway and underground systems, trams, lifts and other transport means.
In addition, direct current is used in conversion plants (installations where different types of energy are converted into electrical direct energy, e.g. photovoltaic plants) and, above all, in those emergency applications where an auxiliary energy source is required to supply essential services, such as protection systems, emergency lighting, wards and factories, alarm systems, computer centers, etc..
Accumulators - for example – constitute the most reliable energy source for these services, both directly in direct current as well as by means of uninterruptible power supply units (UPS), when loads are supplied in alternating current.
[ABB]Когда-то электрическая энергия передавалась и распределялась только на постоянном токе. Но и в настоящее время в отдельных отраслях промышленности постоянный ток применяется достаточно широко.
Возможности использования двигателей постоянного тока и передачи электроэнергии по линии с меньшим числом проводников дают неоспоримые преимущества при электроснабжении железных дорог, подземного транспорта, трамваев, лифтов и т. д.
Кроме того, существуют источники постоянного тока, являющиеся преобразователями различных видов энергии непосредственно в электрическую энергию, например, фотоэлектрические станции. Дополнительные источники постоянного тока применяют в аварийных ситуациях для питания систем защиты, аварийного освещения жилых районов и на производстве, систем сигнализации, компьютерных центров и т. д.
Для решения указанных задач наиболее подходящим источником электроэнергии является аккумулятор. Нагрузки постоянного тока получают электропитание непосредственно от аккумулятора. Нагрузки переменного тока – от источника бесперебойного питания (ИБП), частью которого является аккумулятор.
[Перевод Интент]Direct current can be generated:
- by using batteries or accumulators where the current is generated directly through chemical processes;
- by the rectification of alternating current through rectifiers (static conversion);
- by the conversion of mechanical work into electrical energy using dynamos (production through rotating machines).
[ABB]Постоянный ток можно получить следующими способами:
- от аккумуляторов, в которых электрическая энергия образуется за счет происходящих внутри аккумулятора химических реакций;
- выпрямлением переменного тока с помощью выпрямителей (статических преобразователей);
- преобразованием механической энергии в электрическую с помощью генераторов постоянного тока (вращающихся машин).
[Перевод Интент]In the low voltage field, direct current is used for different applications, which, in the following pages, have been divided into four macrofamilies including:
- conversion into other forms of electrical energy (photovoltaic plants, above all where accumulator batteries are used);
- electric traction (tram-lines, underground railways, etc.);
- supply of emergency or auxiliary services;
- particular industrial installations (electrolytic processes, etc.).
[ABB]Можно выделить четыре области применения постоянного тока в низковольтных электроустановках:
- преобразование различных видов энергии в электрическую (фотоэлектрические установки с аккумуляторными батареями);
- энергоснабжение транспорта на электрической тяге (трамваи, метро и т. д.)
- электропитание аварийных или вспомогательных служб;
- специальные промышленные установки (например, с использованием электролитических процессов и т. п.).
[Интент]Тематики
- электротехника, основные понятия
Синонимы
EN
Русско-английский словарь нормативно-технической терминологии > постоянный ток
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71 технологии для автоматизации
технологии для автоматизации
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[Интент]Параллельные тексты EN-RU
Automation technologies: a strong focal point for our R&D
Технологии для автоматизации - одна из главных тем наших научно исследовательских разработок
Automation is an area of ABB’s business with an extremely high level of technological innovation.
Автоматика относится к одной из областей деятельности компании АББ, для которой характерен исключительно высокий уровень технических инноваций.
In fact, it may be seen as a showcase for exhibiting the frontiers of development in several of today’s emerging technologies, like short-range wireless communication and microelectromechanical systems (MEMS).
В определенном смысле ее можно уподобить витрине, в которой выставлены передовые разработки из области только еще зарождающихся технологий, примерами которых являются ближняя беспроводная связь и микроэлектромеханические системы (micro electromechanical systems MEMS).
Mechatronics – the synthesis of mechanics and electronics – is another very exciting and rapidly developing area, and the foundation on which ABB has built its highly successful, fast-growing robotics business.
Еще одной исключительно интересной быстро развивающейся областью и в то же время фундаментом, на котором АББ в последнее время строит свой исключительно успешный и быстро расширяющийся бизнес в области робототехники, является мехатроника - синтез механики с электроникой.
Robotic precision has now reached the levels we have come to expect of the watch-making industry, while robots’ mechanical capabilities continue to improve significantly.
Точность работы робототехнических устройств достигла сегодня уровней, которые мы привыкли ожидать только на предприятиях часовой промышленности. Большими темпами продолжают расти и механические возможности роботов.
Behind the scenes, highly sophisticated electronics and software control every move these robots make.
А за кулисами всеми перемещениями робота управляют сложные электронные устройства и компьютерные программы.
Throughout industry today we see a major shift of ‘intelligence’ to lower levels in the automation system hierarchy, leading to a demand for more communication within the system.
Во всех отраслях промышленности сегодня наблюдается интенсивный перенос "интеллекта" на нижние уровни иерархии автоматизированных систем, что требует дальнейшего развития внутрисистемных средств обмена.
‘Smart’ transmitters, with powerful microprocessors, memory chips and special software, carry out vital operations close to the processes they are monitoring.
"Интеллектуальные" датчики, снабженные высокопроизводительными микропроцессорами, мощными чипами памяти и специальным программно-математическим обеспечением, выполняют особо ответственные операции в непосредственной близости от контролируемых процессов.
And they capture and store data crucial for remote diagnostics and maintenance.
Они же обеспечивают возможность измерения и регистрации информации, крайне необходимой для дистанционной диагностики и дистанционного обслуживания техники.
The communication highway linking such systems is provided by fieldbuses.
В качестве коммуникационных магистралей, связывающих такого рода системы, служат промышленные шины fieldbus.
In an ideal world there would be no more than a few, preferably just one, fieldbus standard.
В идеале на промышленные шины должно было бы существовать небольшое количество, а лучше всего вообще только один стандарт.
However, there are still too many of them, so ABB has developed ‘fieldbus plugs’ that, with the help of translation, enable devices to communicate across different standards.
К сожалению, на деле количество их типов продолжает оставаться слишком разнообразным. Ввиду этой особенности рынка промышленных шин компанией АББ разработаны "штепсельные разъемы", которые с помощью средств преобразования обеспечивают общение различных устройств вопреки границам, возникшим из-за различий в стандартах.
This makes life easier as well as less costly for our customers. Every automation system is dependent on an electrical network for distributing – and interrupting, when necessary – the power needed to carry out its various functions.
Это, безусловно, не только облегчает, но и удешевляет жизнь нашим заказчикам. Ни одна система автоматики не может работать без сети, обеспечивающей подачу, а при необходимости и отключение напряжения, необходимого для выполнения автоматикой своих задач.
Here, too, we see a clear trend toward more intelligence and communication, for example in traditional electromechanical devices such as contactors and switches.
И здесь наблюдаются отчетливо выраженные тенденции к повышению уровня интеллектуальности и расширению возможностей связи, например, в таких традиционных электромеханических устройствах, как контакторы и выключатели.
We are pleased to see that our R&D efforts in these areas over the past few years are bearing fruit.
Мы с удовлетворением отмечаем, что научно-исследовательские разработки, выполненные нами за последние годы в названных областях, начинают приносить свои плоды.
Recently, we have seen a strong increase in the use of wireless technology in industry.
В последнее время на промышленных предприятиях наблюдается резкое расширение применения техники беспроводной связи.
This is a key R&D area at ABB, and several prototype applications have already been developed.
В компании АББ эта область также относится к числу одной из ключевых тем научно-исследовательских разработок, результатом которых стало создание ряда опытных образцов изделий практического направления.
At the international Bluetooth Conference in Amsterdam in June 2002, we presented a truly ‘wire-less’ proximity sensor – with even a wireless power supply.
На международной конференции по системам Bluetooth, состоявшейся в Амстердаме в июне 2002 г., наши специалисты выступили с докладом о поистине "беспроводном" датчике ближней локации, снабженном опять-таки "беспроводным" источником питания.
This was its second major showing after the launch at the Hanover Fair.
На столь крупном мероприятии это устройство демонстрировалось во второй раз после своего первого показа на Ганноверской торгово-промышленной ярмарке.
Advances in microelectronic device technology are also having a profound impact on the power electronics systems around which modern drive systems are built.
Достижения в области микроэлектроники оказывают также глубокое влияние на системы силовой электроники, лежащие в основе современных приводных устройств.
The ABB drive family ACS 800 is visible proof of this.
Наглядным тому доказательством может служить линейка блоков регулирования частоты вращения электродвигателей ACS-800, производство которой начато компанией АББ.
Combining advanced trench gate IGBT technology with efficient cooling and innovative design, this drive – for motors rated from 1.1 to 500 kW – has a footprint for some power ranges which is six times smaller than competing systems.
Предназначены они для двигателей мощностью от 1,1 до 500 кВт. В блоках применена новейшая разновидность приборов - биполярные транзисторы с изолированным желобковым затвором (trench gate IGBT) в сочетании с новыми конструктивными решениями, благодаря чему в отдельных диапазонах мощностей габариты блоков удалось снизить по сравнению с конкурирующими изделиями в шесть раз.
To get the maximum benefit out of this innovative drive solution we have also developed a new permanent magnet motor.
Стремясь с максимальной пользой использовать новые блоки регулирования, мы параллельно с ними разработали новый двигатель с постоянными магнитами.
It uses neodymium iron boron, a magnetic material which is more powerful at room temperature than any other known today.
В нем применен новый магнитный материал на основе неодима, железа и бора, характеристики которого при комнатной температуре на сегодняшний день не имеют себе равных.
The combination of new drive and new motor reduces losses by as much as 30%, lowering energy costs and improving sustainability – both urgently necessary – at the same time.
Совместное использование нового блока регулирования частоты вращения с новым двигателем снижает потери мощности до 30 %, что позволяет решить сразу две исключительно актуальные задачи:
сократить затраты на электроэнергию и повысить уровень безотказности.These innovations are utilized most fully, and yield the maximum benefit, when integrated by means of our Industrial IT architecture.
Потенциал перечисленных выше новых разработок используется в наиболее полной степени, а сами они приносят максимальную выгоду, если их интеграция осуществлена на основе нашей архитектуры IndustrialIT.
Industrial IT is a unique platform for exploiting the full potential of information technology in industrial applications.
IndustrialIT представляет собой уникальную платформу, позволяющую в максимальной степени использовать возможности информационных технологий применительно к задачам промышленности.
Consequently, our new products and technologies are Industrial IT Enabled, meaning that they can be integrated in the Industrial IT architecture in a ‘plug and produce’ manner.
Именно поэтому все наши новые изделия и технологии выпускаются в варианте, совместимом с архитектурой IndustrialIT, что означает их способность к интеграции с этой архитектурой по принципу "подключи и производи".
We are excited to present in this issue of ABB Review some of our R&D work and a selection of achievements in such a vital area of our business as Automation.
Мы рады представить в настоящем номере "АББ ревю" некоторые из наших научно-исследовательских разработок и достижений в такой жизненно важной для нашего бизнеса области, как автоматика.
R&D investment in our corporate technology programs is the foundation on which our product and system innovation is built.
Вклад наших разработок в общекорпоративные технологические программы группы АББ служит основой для реализации новых технических решений в создаваемых нами устройствах и системах.
Examples abound in the areas of control engineering, MEMS, wireless communication, materials – and, last but not least, software technologies. Enjoy reading about them.
[ABB Review]Это подтверждается многочисленными примерами из области техники управления, микроэлектромеханических систем, ближней радиосвязи, материаловедения и не в последнюю очередь программотехники. Хотелось бы пожелать читателю получить удовольствие от чтения этих материалов.
[Перевод Интент]
Тематики
EN
Русско-английский словарь нормативно-технической терминологии > технологии для автоматизации
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