The features of information technology （IT） are discussed first. On this basis, the features of space information technology （SIT） are presented and SIT is elaborated in five categories. The popularization of SIT ...The features of information technology （IT） are discussed first. On this basis, the features of space information technology （SIT） are presented and SIT is elaborated in five categories. The popularization of SIT is an informatization process and will promote the industrialization of national economy and the modernization of industry such as agriculture. The necessity of the synthetical application of SIT is studied emphatically, and the development trend of SIT is discussed.展开更多
Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours： simulation of spaced based communications and networking project. Its objective is to dem...Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours： simulation of spaced based communications and networking project. Its objective is to demonstrate the feasibility of producing a tool that can provide a performance evaluation of various eonstellation access techniques and routing policies. The architecture and design of the simulation system are explored. The algorithm of data routing and instrument scheduling in this project is described. Besides these, the key methodologies of simulating the inter-satellite link features in the data transmissions are also discussed. The performance of both instrument scheduling algorithm and routing schemes is evaluated and analyzed through extensive simulations under a typical scenario.展开更多
The survivability of computer systems should be guaranteed in order to improve its operation efficiency,especially for the efficiency of its critical functions.This paper proposes a decentralized mechanism based on So...The survivability of computer systems should be guaranteed in order to improve its operation efficiency,especially for the efficiency of its critical functions.This paper proposes a decentralized mechanism based on Software-Defined Architecture(SDA).The concepts of critical functions and critical states are defined,and then,the critical functional parameters of the target system are collected and analyzed.Experiments based on the analysis results are performed for reconfiguring the implementations of the whole system.A formal model is presented for analyzing and improving the survivability of the system,and the problem investigated in this paper is reduced to an optimization problem for increasing the system survival time.展开更多
(November 2009 Beijing, China) STUDY THE TECHNOLOGY OF SPACE INFORMATION EXPLORE THE FUTURE OF HUMAN KINDSponsored by China Academy of Space Technology (CAST) Co-sponsored by The Second Academy of China Aerospace Scie...(November 2009 Beijing, China) STUDY THE TECHNOLOGY OF SPACE INFORMATION EXPLORE THE FUTURE OF HUMAN KINDSponsored by China Academy of Space Technology (CAST) Co-sponsored by The Second Academy of China Aerospace Science and展开更多
为了高效评估弹体在运输过程中的安全性和可靠性,探讨了一种弹体运输中加速度传感器优化布置方法。采用有限元法分析弹体固有特性,通过Fisher信息矩阵2-范数变化率(rate of change,ROC)曲线确定弹体模态阶数。运用有效独立(effective in...为了高效评估弹体在运输过程中的安全性和可靠性,探讨了一种弹体运输中加速度传感器优化布置方法。采用有限元法分析弹体固有特性,通过Fisher信息矩阵2-范数变化率(rate of change,ROC)曲线确定弹体模态阶数。运用有效独立(effective independence,EI)法,计算模态置信准则(modal assurance criterion,MAC)矩阵非对角元素均值,确定传感器布置的最少必要数量;基于模态识别,以MAC矩阵非对角元素最大值为目标,确定初始测点。应用MAC法,以空间准则为约束,考虑传感器数量的影响,比较4种优化算法,优选出传感器布置方案。通过道路模拟运输试验验证了该方法在4种典型路面下的有效性。结果表明,布置结果的MAC评价指标较EI法由0.547降至0.283,且减少了信息冗余的影响,布置方法能够有效准确地布局弹体传感器,适用于弹体振动环境状态监测。展开更多
文摘The features of information technology （IT） are discussed first. On this basis, the features of space information technology （SIT） are presented and SIT is elaborated in five categories. The popularization of SIT is an informatization process and will promote the industrialization of national economy and the modernization of industry such as agriculture. The necessity of the synthetical application of SIT is studied emphatically, and the development trend of SIT is discussed.
基金This project was supported by the National "863" High-Tech Research and Development Program of China(2002AA7170)
文摘Ongoing research is described that is focused upon modelling the space base information network and simulating its behaviours： simulation of spaced based communications and networking project. Its objective is to demonstrate the feasibility of producing a tool that can provide a performance evaluation of various eonstellation access techniques and routing policies. The architecture and design of the simulation system are explored. The algorithm of data routing and instrument scheduling in this project is described. Besides these, the key methodologies of simulating the inter-satellite link features in the data transmissions are also discussed. The performance of both instrument scheduling algorithm and routing schemes is evaluated and analyzed through extensive simulations under a typical scenario.
文摘The survivability of computer systems should be guaranteed in order to improve its operation efficiency,especially for the efficiency of its critical functions.This paper proposes a decentralized mechanism based on Software-Defined Architecture(SDA).The concepts of critical functions and critical states are defined,and then,the critical functional parameters of the target system are collected and analyzed.Experiments based on the analysis results are performed for reconfiguring the implementations of the whole system.A formal model is presented for analyzing and improving the survivability of the system,and the problem investigated in this paper is reduced to an optimization problem for increasing the system survival time.
文摘(November 2009 Beijing, China) STUDY THE TECHNOLOGY OF SPACE INFORMATION EXPLORE THE FUTURE OF HUMAN KINDSponsored by China Academy of Space Technology (CAST) Co-sponsored by The Second Academy of China Aerospace Science and
