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Results of an analysis on impact of space research and technology on developing countries undertaken by the UNISPACE 82 Secretariat on base on national papers submitted by UN member countries to the Conference are reviewed.Experience concerning the implications of a co-operative program on satellite geodesy between the Astronomical Council of the USSR Academy of Sciences and several small countries of Africa, Asia and South America is discussed.  相似文献   
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In the Soviet-French Arcad-3 project, 3 experiments TBF-ONCH, TRAC and ISOPROBE are carried out on board the Aureol-3 satellite to measure the AC and DC electric and magnetic fields and waves. Several modes of telemetry, real time and memory regimes are available for data transmission. TBF-ONCH is devoted to the measurement of 3 components of the DC electric field, 2 electric and 3 magnetic components of the waves. In one mode of the real time telemetry these 5 components are transmitted simultaneously in the frequency range 10 Hz-1.5 kHz in order to be able to determine the wave normal directions of natural emissions and to localize their sources. In the second mode, morphological studies of saucers, chorus, hiss and triggered emissions can be undertaken using the wide band transmission (70 Hz-16 kHz) of any one of these 5 components with the possibility of periodically changing the transmitted component every 4 seconds or keeping the same one during all the pass. TRAC makes use of the on board 3 axis flux gate magnetometer to perform a fine measurement of the magnetic effects of the currents flowing in the vicinity of the spacecraft either in the ionosphere or along the magnetic field lines, with a resolution of ~ 12 nT and in the frequency range from DC to ~ 20 Hz. One component of the HF electric field (0.1–10 Mhz) is measured by ISOPROBE (see companion paper). Examples of inflight measurements from the above instruments and their presentation on microfiches are shown. Some new phenomena are emphasized and briefly discussed.  相似文献   
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A review of the development of photographic tracking techniques in different countries during the recent 5–6 yr is given. Main results of scientific investigations based on observations with Baker-Nunn cameras are considered. New large Soviet, English, French, German cameras are described. Important international projects on photographic tracking for satellite geodesy are reviewed. Main directions of research in this domain are discussed.  相似文献   
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继推出世界首创的"PVD Tiger"之后,瓦尔特又向市场推出了全新的产品,即新一代的CVD涂层切削材料Tiger·tec(R)Silver.现场测试和试验结果表明,该切削材料在性能上获得惊人的提高.  相似文献   
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