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Success probability orientated optimization model for resource allocation of the technological innovation multi-project system

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Journal of Systems Engineering and Electronics 2016年第6期27卷 1227-1237页

作者： Weixu Dai Weiwei Wu Bo Yu Yunhao Zhu School of Management Harbin Institute of Technology institute of spacecraft Systems Engineering China Academy of Space Technology

A success probability orientated optimization model for resource allocation of the technological innovation multi-project system is studied. Based on the definition of the technological innovation multi-project system, the leveling optimization of cost and success probability is set as the objective of resource allocation. The cost function and the probability function of the optimization model are constructed. Then the objective function of the model is constructed and the solving process is explained. The model is applied to the resource allocation of an enterprise's technological innovation multi-project system. The results show that the proposed model is more effective in rational resource allocation, and is more applicable in maximizing the utility of the technological innovation multi-project system. © 2016 Beijing institute of Aerospace Information.

关键词： Cost functions Optimization Probability

Radiation effects on MOS and bipolar devices by 8 MeV protons,60 MeV Br ions and 1 MeV electrons

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Chinese Physics B 2010年第5期19卷 419-426页

作者：李兴冀耿洪滨兰慕杰杨德庄何世禹刘超铭 space Materials & Environment Engineering Laboratory Harbin Institute of Technology School of Astronautics Harbin Institute of Technology

The radiation effects of the metal-oxide-semiconductor （MOS） and the bipolar devices are characterised using 8 MeV protons, 60 MeV Br ions and 1 MeV electrons. Key parameters are measured in-situ and compared for the devices. The ionising and nonionising energy losses of incident particles are calculated using the Geant4 and the stopping and range of ions in matter code. The results of the experiment and energy loss calculation for different particles show that different incident particles may give different contributions to MOS and bipolar devices. The irradiation particles, which cause a larger displacement dose within the same chip depth of bipolar devices at a given total dose, would generate more severe damage to the voltage parameters of the bipolar devices. On the contrary, the irradiation particles, which cause larger ionising damage in the gate oxide, would generate more severe damage to MOS devices. In this investigation, we attempt to analyse the sensitivity to radiation damage of the different parameter of the MOS and bipolar devices by comparing the irradiation experimental data and the calculated results using Geant4 and SRIM code.

关键词： radiation effects MOS and bipolar devices ionisation damage displacement damage

A magnetic bald-patch flare in solar active region 11117

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Research in Astronomy and Astrophysics 2017年第9期17卷 51-60页

作者： Chao-Wei Jiang Xue-Shang Feng Shi-Tsan Wu Qiang Hu institute of space Science and Applied Technology Harbin Institute of Technology SIGMA Weather Group State Key Laboratory for Space Weather Center for Space Science and Applied ResearchChinese Academy of Sciences Center for space Plasma and Aeronomic Research The University of Alabama in Huntsville

With SDO observations and a data-constrained magnetohydrodynamics （MHD） model, we identify a confined multi-ribbon flare that occurred on 2010 October 25 in solar active region 11117 as a magnetic bald patch （BP） flare with strong evidence. From the photospheric magnetic field observed by SDO/HMI, we find there are indeed magnetic BPs on the polarity inversion lines （PILs） which match parts of the flare ribbons. From the 3D coronal magnetic field derived from an MHD relaxation model constrained by the vector magnetograms, we find strikingly good agreement of the BP separatrix surface （BPSS） footpoints with the flare ribbons, and the BPSS itself with the hot flaring loop system. Moreover, the triggering of the BP flare can be attributed to a small flux emergence under the lobe of the BPSS, and the relevant change of coronal magnetic field through the flare is reproduced well by the pre-flare and post-flare MHD solutions, which match the corresponding pre- and post-flare AIA observations, respectively. Our work contributes to the study of non-typical flares that constitute the majority of solar flares but which cannot be explained by the standard flare model.

关键词： Sun flares -- Sun corona- magnetic fields - magnetohydrodynamics (MHD) - methods numerical

Reconfigurability evaluation method for input-constrained control systems

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1023-1030页

作者： TU Yuanyuan WANG Dayi LI Wenbo Beijing institute of Control Engineering China Academy of Space TechnologyBeijing 100190China Beijing institute of spacecraft System Engineering China Academy of Space TechnologyBeijing 100190China

This paper proposes a quantitative reconfigurability evaluation method for control systems with actuator saturation and additive faults from the perspective of system *** the saturated feedback law in the convex hull of a group of auxiliary linear controls,the sufficient reconfigurability conditions for the system under additive faults are derived using invariant *** conditions are then expressed as linear matrix inequalities(LMIs)and applied to quantify the degree of reconfigurability for the fault *** largest fault magnitude for which the system can be stabilized,the largest initial state domain from which all the trajectories are convergent,and the minimum final state domain to which the trajectories will converge are *** effectiveness of the proposed method is illustrated through an application example.

关键词： control reconfigurability additive fault actuator saturation invariant set fault-tolerant control

Geometry-based distributed arc-consistency method formultiagent planning and scheduling

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Science China(Technological Sciences) 2019年第1期62卷 133-143页

作者： XU Rui LI ZhaoYu CUI PingYuan institute of Deep space Exploration Technology School of Aerospace Engineering Beijing Institute of Technology Key Laboratory of Autonomous Navigation and Control for Deep space Exploration Ministry of Industry and Information Technology

This research focuses on building a distributed algorithm for planning and scheduling multiple agents to help people deal with events beyond their cognitive capacity, such as car assembly, factory management, spacecraft constellation, etc. We address not only the efficiency of the algorithm but also communication and the individual privacy. As to reason over the problems with multiple agents which are distributed but interconnected, a formal account of the Action-centric Multiagent Simple Temporal Problem(AMSTP) is put forward using the representation of geometries. The key technique we build on is a novel distributed arc-consistency algorithm centered by the geometric method called GDAC, which pays attention to how an agent's local subproblem affects other agents' subproblems. The GDAC is based on geometries taking the action rather than the timepoint as a variable, which can deal with continuous intervals and decrease the number of variables. Comprehensive experiments are run and the proposed technique outperforms the competitor and shows considerable merit compared to the centralized algorithm.

关键词： arc consistency multiple agents planning and scheduling

A Hybrid Compression Framework for Large Scale Trajectory Data in Road Networks

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Chinese Journal of Electronics 2015年第4期24卷 730-739页

作者： WU Peili TAN Yu'an ZHENG Jun ZHANG Quanxin LI Yuanzhang CHENG Zijing School of Computer Science and Technology Beijing Institute of Technology space Star Technology CO. Ltd China Academy of space Technology

A Hybrid compression framework of trajectory data(HCFT) is proposed for effective compression of tra jectory data with road network limited. It’s different from the present researches which mainly focus on compression of single tra jectory, and further takes data redundancy raised by the similarity of movement pattern of moving objects into consideration. HCFT divides the redundancy of tra jectory data into Single tra jectory redundancy(STR) and Multiple tra jectories redundancy(MTR) and compresses them in a hybrid way(i.e. synchronous compression for STR at first and then asynchronous compression for MTR). We propose an asynchronous extraction algorithm for MTR based on frequent Road track subsequence(RTS), which replaces similar movement route by RTS, with the complexity of calculation significantly reduced. HCFT can not only gain higher compression ratio,but also ensure effectiveness of compressed tra jectory. We also verify effectiveness and superiority of the new method according to the experiments of real tra jectory dataset.

关键词： Trajectory data Movement similarity Road track Dictionary coding Multi-tra jectories compression

An analysis of the correlation between the fluxes of high-energy electrons and low-middle-energy electrons in the magnetosphere

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Science China(Technological Sciences) 2016年第7期59卷 1130-1136页

作者： LI ChenFang ZOU Hong ZONG QiuGang JIA XiangHong CHEN HongFei SHI WeiHong YU XiangQian institute of space Physics and Applied Technology School of Earth and Space Science Peking University State Key Laboratory of space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center

The variation of the flux of energetic electrons in the magnetosphere has been proven to be strongly related to the solar wind speed. Observations of GEO orbit show that the flux of low-energy electrons is not only modulated by the solar wind speed, but, if a time delay is added, is also positively correlated to the flux of high-energy electrons. This feature provides a possible method to forecast the flux of high-energy electrons in GEO orbit. In this study, the correlations of the fluxes between the high-energy electrons and low-middle-energy electrons obtained at different L values and in different orbits are investigated to develop the application of this feature. Based on the analysis of long–term data observed by NOAA POES and GOES, the correlations between the fluxes of high-energy electrons and low–middle–energy electrons are good enough at different L values and in different orbits in quiet time, but this correlation is strongly affected by CME–driven geomagnetic storms.

关键词： magnetosphere high-energy electrons low-middle energy electrons forecast model

Discussion on the geometric factor in the detection of high energy electrons in geospace

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Science China(Technological Sciences) 2008年第1期51卷 1-9页

作者： CHEN HongFei SHI WeiHong ZOU Hong ZOU JiQing institute of space Physics and Applied Technology School of Earth and Space SciencesPeking UniversityBeijing 100871China

High energy electron is a kind of sources to be detected in the geospace environ- ment. Generally, the particle telescope with much thick semiconductor detector is used as the sensor for energetic electrons because they can penetrate deeply into the detector. The more energy of the electrons is, the deeper they can penetrate into, so that the geometric factor varies with energy of the incident electrons. We discuss the geometric factor of particle radiation detector (PRD), which is a payload on ZY-1 (CBERS-1 and CBERS-2) satellites to monitor the high energy particle ra- diation inside the satellites. According to the NASA’s AE8 model, the geometric factors of electrons for the low energy bin (0.5―1.0 MeV) and the high energy bin (> 2.0 MeV) are 2.468 and 1.736 cm2·sr, respectively. These results are much differ- ent from the traditional calculation of the geometric factor that is 1.18 cm2·sr. The angle-response function of the telescope is also derived, which can be useful for design of the telescope and analysis of the directional distribution.

关键词： geometric factor high energy electrons particle radiation space exploration

Two-channel model based adaptive schlieren detection algorithm for BOS system

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Journal of Systems Engineering and Electronics 2019年第2期30卷 251-258页

作者： LIU Han ZHANG Yanmei ZHAO Baojun GUO Haichao ZHAO Boya School of Information and Electronics Beijing Institute of Technology National Key Laboratory of Science and Technology on space Microwave China Academy of Space Technology

A schlieren detection algorithm is proposed for the ground-to-air background oriented schlieren(BOS) system to achieve high-speed airplane shock waves visualization. The proposed method consists of three steps. Firstly, image registration is incorporated for reducing errors caused by the camera ***, the background subtraction dual-model single Gaussian model(BS-DSGM) is proposed to build a precise background model. The BS-DSGM could prevent the background model from being contaminated by the shock waves. Finally, the twodimensional orthogonal discrete wavelet transformation is used to extract schlieren information and averaging schlieren data. Experimental results show our proposed algorithm is able to detect the aircraft in-flight and to extract the schlieren information. The precision of schlieren detection algorithm is 0.96. Three image quality evaluation indices are chosen for quantitative analysis of the shock waves visualization. The white Gaussian noise is added in the frames to validate the robustness of the proposed ***, we adopt two times and four times down sampling to simulate different imaging distances for revealing how the imaging distance affects the schlieren information in the BOS system.

关键词： background model background oriented schlieren (BOS) schlieren detection wavelet decomposition