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991.
992.
提出了"需求拉动式"航空器材库存控制模式,建立了基于可靠性分析的航空器材需求预测模型.该模型通过对航空器材使用信息进行可靠性分析,得出零件可靠性寿命函数,并根据给定可靠度下的零件寿命预测航空器材需求时间.最后对视情维护下的周转件需求预测与库存控制进行了案例分析. 相似文献
993.
G.P. Wu G.L. Huang Y. Huang D.Y. Wang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(6):984-987
Based upon the most efficient electron acceleration near the midplane of 3D non-neutral driven reconnecting current sheet (RCS) and the electrostatic wave excitation by the drift Maxwellian distribution of electrons in Vlasov simulation, we assume that the electrostatic waves mainly propagate opposite to the reconnecting electric field and investigated how these waves affect the electron acceleration. The main results are: (1) when the electron’s velocity equals to the phase speed of the waves, they will be trapped and have the different accelerating characteristics from the untrapped electrons through solving the momentum equations of electrons analytically; (2) the test particle simulations further prove that the number of the energetic electrons decreases with the increasing intensity of unstable waves, and the distribution of the energetic electrons takes on the double power-law. 相似文献
994.
He Ying 《中国航天(英文版)》2008,(4)
By October 23,Chang'e-1 satellite with a one-year design lifetime has been operating in lunar orbit for one year,completed more than 4000 orbits,covering the entire moon 12 times.The satellite's platform works normally at present and all systems and equipment onboard work in their main mode.The satellite has obtained a large quantity of scientific data and achieved the preset objectives of precise orbit maneuver,successful moon orbiting,effective exploration and one- year lifetime.The Chang'e-1 mission i... 相似文献
995.
996.
针对目前卫星地面应用系统中设备监控软件可重用性差的缺点,提出一种可扩展的通用设备监控软件框架设计方案.结合模块化和抽象接口设计思想,简化了组件开发,提高了软件的复用性.通过控制反转技术,降低了组件之间的耦合,使框架更加易于扩展,在实际应用中取得了良好的效果. 相似文献
997.
根据数字化制造企业的安全需求特点,系统构建了数字化企业信息安全体系,并将多种安全方案纳入到该体系中。针对数字化企业数据及资料安全问题,提出了一套综合解决方案,该方案实现了身份鉴别、设备集中控制、文档权限管理、文档加密、安全审计,大大提高了企业内部数据及资料的安全性。提出了一种典型数字化企业的信息安全实施方案,保障了内部业务应用系统的信息安全。 相似文献
998.
999.
Y. Wu S.G. Jin Z.M. Wang J.B. Liu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The detection and repair of the cycle slip or gross error is a key step for high precision global positioning system (GPS) carrier phase navigation and positioning due to interruption or unlocking of GPS signal. A number of methods have been developed to detect and repair cycle slips in the last two decades through cycle slip linear combinations of available GPS observations, but such approaches are subject to the changing GPS sampling and complex algorithms. Furthermore, the small cycle slip and gross error cannot be completely repaired or detected if the sampling is quite longer under some special observation conditions, such as Real Time Kinematic (RTK) positioning. With the development of the GPS modernization or Galileo system with three frequencies signals, it may be able to better detect and repair the cycle slip and gross error in the future. In this paper, the cycle slip and gross error of GPS carrier phase data are detected and repaired by using a new combination of the simulated multi-frequency GPS carrier phase data in different conditions. Results show that various real-time cycle slips are completely repaired with a gross error of up to 0.2 cycles. 相似文献
1000.
He Ying 《中国航天(英文版)》2012,(4):12-13
(Continued) The 79th Launch On September 9, 2004, a LM-4B launch vehicle launched two satellites, SJ-6A and SJ-6B, into space both for space environment exploration from the Taiyuan Satellite Launch Center. The two satellites entered their preset sun synchronous orbits. Launch Site: Taiyuan Satellite Launch Center Launch Result: Success At 07:14 Beijing time on September 9, the LM-4B launch vehicle was launched into space with SJ-6A and SJ-6B on board. 相似文献