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Journal of Computational Mathematics 1998年第1期16卷 15-26页

作者： Yue-shan Xiong (Department of Computer, national university Of defense technology, Changsha, china) 国防科技大学计算机系湖南长沙

We develop a combined Fourier spectral-finite difference method for solving 2-dimensional, semi-periodic compressible fluid how problem. The error estimation, as well as the convergence rate, is presented.

关键词： spectral-difference method compressible fluid flow error estimation

Narrowband imaging method for spatial precession cone-shaped targets

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Science china(Technological Sciences) 2010年第4期53卷 942-949页

作者： DING XiaoFeng1,FAN MeiMei1,WEI XiZhang1,LI Xiang1 & Xiao HuaiTie2 1 Institute of Space Electronics Information technology,national university of defense technology,Changsha 410073,china 2 School of Electronic Science and Engineering,national university of defense technology,Changsha 410073,china Institute of Space Electronics Information technology National University of Defense Technology Changsha China School of Electronic Science and Engineering National University of Defense Technology Changsha China

The imaging method of the mid-course missile is the key technique of the missile defense *** of the special precession character of the ballistic missile warhead,the inverse synthetic aperture radar method cannot realize phase compensation with the constant phase offset function,which leads to blurring of the *** this paper,we propose a new narrowband radar imaging method for the precession cone-shaped *** method acquires the Doppler modulation of the precession target's scattering centers with high resolution time-frequency analysis method and extracts the Doppler parameter from the result of the time-frequency analysis with the general Radon transform,then reconstructs the scattering centers positions in the parameter *** experiment results with the anechoic chamber data of the representative cone-shaped object showed the effectiveness of the method.

关键词： narrowband radar imaging time-frequency analysis general Radon transform

Review on abort trajectory for manned lunar landing mission

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Science china(Technological Sciences) 2010年第10期53卷 2691-2698页

作者： XI XiaoNing1, HUANG WenDe2 & WANG Wei2,3 1 College of Mechatronics Engineering and Automation, national university of defense technology, Changsha 410073, china 2 College of Aerospace and Material Engineering, national university of defense technology, Changsha 410073, china 3 School of Surveying and Spatial Information System, university of New South Wales, Sydney, NSW 2052, Australia College of Mechatronics Engineering and Automation National University of Defense Technology Changsha China College of Aerospace and Material Engineering National University of Defense Technology Changsha China School of Surveying and Spatial Information System University of New South Wales Sydney Australia

Abort trajectory is a passage that ensures the astronauts to return safely to the earth when an emergency occurs. Firstly,the essential elements of mission abort are analyzed entirely based on summarizing the existing studies. Then,abort trajectory requirement and rational selection for different flight phases of typical manned lunar mission are discussed specifically. Considering a trade-off between the two primary constrains of an abort,the return time of flight and energy requirement,a general optimizing method for mission abort is proposed. Finally,some suggestions are given for china’s future manned lunar landing mission.

关键词： manned lunar landing mission abort trajectory design free return trajectory

Trajectory Estimation with Multi-range-rate System Based on Sparse Representation and Spline Model Optimization

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Chinese Journal of Aeronautics 2010年第1期23卷 84-90页

作者： Liu Jiying,Zhu Jubo,Xie Meihua Department of Mathematics and Systems Science,national university of defense technology,Changsha 410073,china Department of Mathematics and Systems Science National University of Defense Technology Changsha 410073 China

The classic state methods for trajectory estimation in boost phase with multi-range-rate system include method of point-by-point manner and that of spline-model-based manner. Both are deficient in terms of model-approximation accuracy and systematic error determination thus resulting in the estimation errors well beyond the requirements, especially, concerning the maneuvering trajectory. This article proposes a new high-precision estimation approach based on the residual error analysis. The residual error comprises three components, i. e. systematic error, model truncation error and random error. The approach realizes self-adaptive estimation of systematic errors in measurements following the theory of sparse representation of signals to minimize the low-frequency components of residual errors. By taking median- and high-frequency components as indexes, the spline model-approximation is improved by optimizing node sequence of the spline function and the weight selection for data fusion through iteration. Simulation has validated the performances of the proposed method.

关键词： tracking radar systematic errors truncation error sparse representation splines

Data fusion techniques for incomplete measurement of trajectory

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Chinese Science Bulletin 2001年第8期46卷 627-630页

作者： ZHU JuboDepartment of Mathematics & System Science, national university of defense technology, Changsha 410073, china Department of Mathematics & System Science National University of Defense Technology Changsha China

This paper focuses on data processing for incomplete measurement of trajectory (IMT) in aerospace measurement and control. The IMT means that the principal equipment loses the measured data during some intervals so that trajectory parameters (position, velocity, etc.) cannot be determined independently. Based on a joint model for trajectory estimation with reduced parameter, a fusion way is put forth by making full use of measured data from auxiliary equipment with lower precision. In the superposition intervals of measurement between principal and auxiliary equipment, the technique of diagnosing and estimating system errors is applied to improving the estimate precision of trajectory parameters (TP) and determining the precision after data fusion. In practical test, this method operates so successfully that it can not only provide complete TP but improve their precision remarkably. Meanwhile, this way is also applicable to other problems of incomplete measurement.

关键词： incomplete measurement of trajectory data fusion re- duced parameter model error diagnose.

Near lossless compression of hyperspectral images based on distributed source coding

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Science china(Information Sciences) 2012年第11期55卷 2646-2655页

作者： NIAN YongJian1,WAN JianWei1,TANG Yi1 & CHEN Bo2 1College of Electronic Science and Engineering,national university of defense technology,Changsha,410073,china 2College of Science,national university of defense technology,Changsha,410073,china College of Electronic Science and Engineering National University of Defense Technology Changsha China College of Science National University of Defense Technology Changsha China

Effective compression technique of on-board hyperspectral images has been an active topic in the field of hyperspectral remote *** order to solve the effective compression of on-board hyperspectral images,a new distributed near lossless compression algorithm based on multilevel coset codes is *** to the diverse importance of each band,a new adaptive rate allocation algorithm is proposed,which allocates rational rate for each band according to the size of weight factor defined for hyperspectral images subject to the target rate *** prediction is introduced for Slepian-Wolf lossless coding and an optimal quantization algorithm is presented under the correct reconstruction of Slepian-Wolf decoder,which minimizes the distortion of reconstructed hyperspectral images under the target *** Slepian-Wolf encoder exploits the correlation of the quantized values to generate the final bit *** results show that the proposed algorithm has both higher compression efficiency and lower encoder complexity than several existing classical algorithms.

关键词： hyperspectral images near lossless compression Slepian-Wolf coding distributed source coding

A logistic regression model for Semantic Web service matchmaking

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Science china(Information Sciences) 2012年第7期55卷 1715-1720页

作者： WEI DengPing 1 ,WANG Ting 1 & WANG Ji 2 1 School of Computer,national university of defense technology,Changsha 410073,china 2.national Laboratory for Parallel and Distributed Processing,Changsha 410073,china School of Computer National University of Defense Technology Changsha China national Laboratory for Parallel and Distributed Processing Changsha China

Semantic Web service matchmaking,as one of the most challenging problems in Semantic Web services (SWS),aims to filter and rank a set of services with respect to a service query by using a certain matching *** this paper,we propose a logistic regression based method to aggregate several matching strategies instead of a fixed integration (e.g.,the weighted sum) for SWS *** logistic regression model is trained on training data derived from binary relevance assessments of existing test collections,and then used to predict the probability of relevance between a new pair of query and service according to their matching values obtained from various matching *** are then ranked according to the probabilities of relevance with respect to each *** method is evaluated on two main test collections,SAWSDL-TC2 and Jena Geography Dataset(JGD).Experimental results show that the logistic regression model can effectively predict the relevance between a query and a service,and hence can improve the effectiveness of service matchmaking.

关键词： Semantic Web service matchmaking logistic regression

Carrying capacity for the electromagnetic suspension low-speed maglev train on the horizontal curve

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Science china(Technological Sciences) 2010年第4期53卷 1082-1087页

作者： CUI Peng,LI Jie & LIU DeSheng Maglev Engineering Center,national university of defense technology,Changsha 410073,china Maglev Engineering Center National University of Defense Technology Changsha China

Aiming at the lateral dislocation between the electromagnets and the rails on a horizontal curve,we investigated a single magnetic bogie of the maglev train in this *** magnetic levitation and guidance forces supplied by the suspension modules were deduced by the flux tube *** to the dynamic equilibrium equations of the maglev train on the curved track with cant,several major factors that influence the carrying capacity were analyzed,and the formula of the carrying capacity was *** results provide a theoretical reference for the design of maglev train.

关键词： low-speed maglev train curve flux tube carrying capacity

The Extension of Hypergame Analysis and Its Application

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Journal of Systems Engineering and Electronics 1994年第2期5卷 47-52页

作者： Shu Jiang and Liu Deming (national university of defense technology. Hunan. 410073, P. R .china) national university of defense technology Hunan 410073 P.R. China

The hypergame analysis mainly processes the conflict in which one or more of the players are notfully aware of the nature of the conflict situation. it is a kind of qualitative technology which describes thedecieve and anti-decieve *** defect of hypergame analysis appears in that the decision goalcombines with the course of the decision analysis. This paper puts forward the concept 'sanctioned rampart', which reflects the dynamics course of players' decision analysis based on decision goal. At the *** extended hypergame is used to analyse the whole course of 'Gulf Crisis'.

关键词： Conflict analysis Hypergame Sanctioned chain. Sanctioned rampart.