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	Using Event-Based Method to Estimate Cybersecurity Equilibrium 期刊论文 OAI收割 IEEE/CAA Journal of Automatica Sinica, 2021, 卷号: 8, 期号: 2, 页码: 455-467 作者: Zhaofeng Liu; Ren Zheng; Wenlian Lu; Shouhuai Xu \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2021/04/09 Cybersecurity dynamics cybersecurity equilibrium event-based method global state estimation preventive and reactive cyber defense dynamics
	Application of Vague set to Software rating ascertainment for space camera (EI CONFERENCE) 会议论文 OAI收割 2nd International Conference on Information Science and Engineering, ICISE2010, December 4, 2010 - December 6, 2010, Hangzhou, China 作者: Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Software rating ascertainment is very important in development of space camera software system. It can guide the software measurement and management and help designer improve system reliability finally. Fault Tree Analysis is a common method to analyze the danger reason and fix on bottom events. The most significant step is calculating the occurrence probabilistic of top event namely the occurrence probabilistic of dangerous event. Because software failure cause is anfractuous and available data are hard to get a modeling method for bottom event is proposed based on Vague set to calculate the occurrence probabilistic of top event. Experimental results show that the new approach of Vague set can guide the Software rating ascertainment which is ascertained using qualitative analysis. The results also show that the new method makes software rating ascertainment have the quantificational evidence. 2010 IEEE.
	Application of CMOS APS star tracker with large FOV in attitude and angular velocity determination (EI CONFERENCE) 会议论文 OAI收割 Advanced Sensor Systems and Applications III, November 12, 2007 - November 14, 2007, Beijing, China Lu D.; Guang J.; Shaoju W.; Tao C. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 The paper deals with the spacecraft attitude determination problem using a new kind of star tracker with large FOV based on CMOS APS. Star tracker has been developed since 1970s and proved to be the most accurate sensor ever used in the spacecraft attitude determination systems. But the traditional CCD star tracker also has some disadvantages such as small FOV high power consumption low sample rate and low working angular rate limit which prevent the use of CCD star tracker in attitude large angle maneuvering process. The new kind of star tracker based on CMOS APS has no such disadvantages and is more applicable on modern low-cost agile small satellites. Its higher sample rate and working angular rate limit over traditional CCD star tracker make it more adapt for spacecraft angular velocity determination. Because of the large FOV of the star tracker the mathematical model of traditional CCD star tracker with a small FOV is not appropriate. So a new mathematical model was quoted to fit the star tracker with a large FOV. An alternative adaptive algorithm was also introduced in the paper. It can help the EKF algorithm work lacking of accurate covariance of the observation noise. An optimal estimation algorithm was used to estimate the angular velocity directly from the star tracker measurements. Mathematic simulation results indicate the CMOS APS star tracker can give accurate attitude information and estimated angular rate. The method can be used as the chief attitude determination system design of low-cost satellite without gyros or be used as a backup strategy in the event of gyro failures to enhance the reliability of the attitude determination system.