Shi W.J.,Institute of Spacecraft System Engineering CAST |
Zhang Y.B.,Beihang University |
Hu W.P.,Beihang University
Advanced Materials Research | Year: 2013
In this paper, a fatigue life prediction method for fiber reinforced polymer composite lamina is proposed. Based on two independent introduced damage variables, the damage degree of fiber and the damage degree of matrix, the issue of lamina fatigue is transformed into the study of damage evolution for fiber and matrix. Subsequently, the damage driving force and the damage evolution equations for the fiber and the matrix are constructed, respectively. Then, a novel parameter identified method is conducted. Finally, with the failure criterion for the lamina presented, the fatigue life prediction method of the composite lamina is proposed. © (2013) Trans Tech Publications, Switzerland.
Bin B.,CAS Institute of Mechanics |
Ning L.,CAS Institute of Mechanics |
Nin P.,CAS Institute of Mechanics |
Nin P.,Institute of Spacecraft System Engineering CAST |
Han Z.,CAS Institute of Mechanics
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013
As the development of semiconductor technology, the manufacture process of CCD sensors has been improved continuously. In recent years some new technologies appear on CCD sensors. Analog pixel Binning technology is one of them. In this paper, a new signal-processing system of digital pixel binning based on bi-cubic filtering algorithm is designed.The system overcomes the shortcomings of losing some image details, caused by analog pixel binning which does simply summation of pixel signals. The signal-processing system of digital pixel binning can keep high frequency information through bi-cubic filtering algorithm, which can improve the contrast and MTF of the remote sensing images. This system can achieve pixel binning with lower computational complexity and also it has the good real-time capability for large-scale remote sensing images. © 2013 SPIE.
Zhang Y.-T.,Institute of Spacecraft System Engineering CAST |
Cai Z.,Ministry of Industry and Information Technology Software and Integrated Circuit Promotion Center |
Liu S.,Harbin Engineering University
Dianbo Kexue Xuebao/Chinese Journal of Radio Science | Year: 2011
Aiming at the propagation characteristics of electromagnetic waves in loss media, a modified alternative direction implicit finite difference time domain (ADI-FDTD) method is proposed to solve the problem. The modified method can improve the disadvantage of the traditional ADI-FDTD method, which improves the computational efficiency on the cost of accuracy. The unconditional stability of the algorithm is proved, while the numerical dispersion is also analyzed. The algorithm is validated effectively, and it could also improve computational accuracy, which has been proved by examples comparison. The algorithm is applied to analyze the scattering of a metal sphere in air, on the bottom of ground and sea. The simulation shows that the amplitude and oscillation of the scattering increase in the loss media. Copyright © 2011 by Editorial Department of Chinese Journal of Radio Science.
Xiong X.,Institute of Spacecraft System Engineering CAST |
Wang J.,Institute of Spacecraft System Engineering CAST |
Zhang P.,Beihang University
Safety and Reliability of Complex Engineered Systems - Proceedings of the 25th European Safety and Reliability Conference, ESREL 2015 | Year: 2015
A new method of failure detection for damaged or floating control surface is proposed, which is only based on the information of electric actuator, avoiding the combined effects caused by the concurrent failure of control surfaces. By constructing the model of actuator system and observing the characteristics of internal physical parameters of actuator under floating/damage failure, the relationship between actuator’s armature current and the failure mode is found and the judgment theorem is given. The feasibility of the proposed method is verified by simulation example. The comparison of performance between the proposed method and the traditional FDI (failure detection and identification) method (Filter Method) on detecting concurrent failure of control surfaces is showed. The results suggest that the proposed failure detection method is efficient and accurate in detecting and locating the failure regardless of whether or not the system noise is considered. This method is independent from the complexity of the flight control system since it is only based on single electric actuator. Therefore it could be used for both linear system and nonlinear system. The proposed failure detection method is efficient and applicable in realistic engineering scenario. © 2015 Taylor & Francis Group, London.
Yan D.,Institute of Spacecraft System Engineering CAST |
Wang L.,Institute of Spacecraft System Engineering CAST
ICEIEC 2015 - Proceedings of 2015 IEEE 5th International Conference on Electronics Information and Emergency Communication | Year: 2015
Satellite network has the advantage of global coverage and simple access, so it is considered to be an important part of next generation Internet. In this paper, we propose a novel traffic prediction based dynamic routing technique for double-layered satellite networks, which is called TPDR. It has a double-layered structure, which is composed of LEO layer and GEO layer. TPDR supports new nodes to join the network, and prevent the manager nodes from becoming overloaded based on traffic prediction. In the end, the performances of end-to end delay and manager packet loss rate are evaluated by simulations. © 2015 IEEE.