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设计了一个智能贮水水箱液位检测与水泵控制装置,能监控2m范围内的水位变化,测量精度1cm,测量时与被测液位无直接接触,能够清晰稳定的显示结果,在水位超出上、下限时发出声光报警,并能准确地控制水泵工作。 相似文献
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A strategy is being developed whereby the current set of internationally standardized space data communications protocols can be incrementally evolved so that a first version of an operational "Interplanetary Internet" is feasible by the end of the decade. This paper describes its architectural concepts, discusses the current set of standard space data communications capabilities that exist to support Mars exploration and reviews proposed new developments. We also speculate that these current capabilities can grow to support future scenarios where human intelligence is widely distributed across the Solar System and day-to-day communications dialog between planets is routine. 相似文献
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Des Marais DJ Harwit MO Jucks KW Kasting JF Lin DN Lunine JI Schneider J Seager S Traub WA Woolf NJ 《Astrobiology》2002,2(2):153-181
The major goals of NASA's Terrestrial Planet Finder (TPF) and the European Space Agency's Darwin missions are to detect terrestrial-sized extrasolar planets directly and to seek spectroscopic evidence of habitable conditions and life. Here we recommend wavelength ranges and spectral features for these missions. We assess known spectroscopic molecular band features of Earth, Venus, and Mars in the context of putative extrasolar analogs. The preferred wavelength ranges are 7-25 microns in the mid-IR and 0.5 to approximately 1.1 microns in the visible to near-IR. Detection of O2 or its photolytic product O3 merits highest priority. Liquid H2O is not a bioindicator, but it is considered essential to life. Substantial CO2 indicates an atmosphere and oxidation state typical of a terrestrial planet. Abundant CH4 might require a biological source, yet abundant CH4 also can arise from a crust and upper mantle more reduced than that of Earth. The range of characteristics of extrasolar rocky planets might far exceed that of the Solar System. Planetary size and mass are very important indicators of habitability and can be estimated in the mid-IR and potentially also in the visible to near-IR. Additional spectroscopic features merit study, for example, features created by other biosignature compounds in the atmosphere or on the surface and features due to Rayleigh scattering. In summary, we find that both the mid-IR and the visible to near-IR wavelength ranges offer valuable information regarding biosignatures and planetary properties; therefore both merit serious scientific consideration for TPF and Darwin. 相似文献
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航天工业部于1987年12月15日至17日在南京召开“五公分Ⅱ型杂波干扰机”、“X波段速度欺骗干扰模拟机”、“Ku波段欺骗式干扰模拟器兼目标模拟器”三项成果的部级鉴定会。部内外24个单位44位专家参加了本次鉴定会。鉴定委员和全体代表听取了8511所代表所作的研制总结报告、标准化审查和质量分析报 相似文献
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李建新 《华北航天工业学院学报》2005,15(2):9-11
笔者对我市信息化建设的现状进行了调查,对我市信息化建设在整体应用、统一规划、管理制度、人才机制等方面存在的问题进行了分析,并提出了加快我市信息化建设应以构筑“数字廊坊”为重点,着力抓好政务领域信息化和信息技术应用等具体措施。这些措施可以对中小城市信息化建设起到参考作用。 相似文献
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Barmin I Bryukhanov N Egorov A Filatov I Markov A Senchenkov A Tsvetkov V 《Acta Astronautica》2002,51(1-9):255-259
The problem is considered of using the PROGRESS transport spacecraft, which will deliver the payload on the ISS, as a free flying platform for realization of space experiments. For maintenance of the ISS 5-6 PROGRESS flights per year are planned. Usually after delivery of the payload the PROGRESS undocks from the ISS and burns down in the Earth atmosphere. However, the operating conditions of its onboard systems allow to prolong operation and to make free flight near to the station and repeatedly to be docked to it. It is offered to use this possibility for performing experiments on Material Science. 相似文献