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Novel discrimination method of digital deceptive jamming in mono-pulse radar

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Journal of Systems Engineering and Electronics 2011年第6期22卷 910-916页

作者： Huanyao Dai xuesong Wang Yongzhen li School of Electronic Science and Engineering National University of Defense Technology Changsha 410073 P. R. China

A new polarization measurement algorithm by using the sum and difference beam differential property of mono-pulse radar is *** on the generation mechanism differences between the target scattering and multi-false-target jamming,the signal models of real targets and digital deceptive false target jamming for sum and delta channel are *** polarization discrimination parameters are designed,and the discrimination method and its performance are *** novel method does not need the accurate estimation of the absolute value of full target polarization scattering matrix,but only requires the relative estimation of the orthogonal polarized component of the *** the need to add additional polarization channels,the proposed method is more suitable for engineering *** simulation experiment verifies that the correctly identifying probability can be better than 90%.

关键词： discrimination multi-false-target jamming polarization pattern difference sum-difference beam.

Cures for expansion shock and shock instability of Roe scheme based on momentum interpolation mechanism

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Applied Mathematics and Mechanics(English Edition) 2018年第4期39卷 455-466页

作者： xuesong li Xiaodong REN Chunwei GU Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal Engineering Tsinghua University

The common defects of the Roe scheme are the non-physical expansion shock and shock instability. By removing the momentum interpolation mechanism(MIM), an improved method with several advantages has been presented to suppress the shock instability. However, it cannot prevent the expansion shock and is incompatible with the traditional curing method for expansion shock. To solve the problem, the traditional curing mechanism is analyzed. Effectiveness of the traditional curing method is discussed,and several defects are identified, one of which leads to incompatibility between curing shock instability and expansion shock. Consequently, an improved Roe scheme is proposed, which is with low computational costs, concise, easy to implement, and *** importantly, the proposed scheme can simultaneously solve the problem of shock instability and expansion shock without additional costs.

关键词： Roe scheme expansion shock shock instability momentum interpolation mechanism(MIM) robust curing method

Instantaneous measurement for radar target polarization scattering matrix

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Journal of Systems Engineering and Electronics 2010年第6期21卷 968-974页

作者： Yong liu Yongzhen li xuesong Wang School of Electronic Science and Engineering National University of Defense Technology Changsha 410073 P. R. China

Adopting ＂simultaneous transmitting, simultaneous receiving＂ operational scheme, instantaneous polarization radar （IPR） can measure target polarization scattering matrix （PSM） using only once target echoes in two orthogonal polarization channels. Firstly, signal model and signal process are advanced under narrowband condition. Secondly, measurement performances of two typical IPR waveforms are analyzed in detail. At last, field experiments are carried out using X-band IPR system designed by National University of Defense Technology （NUDT）, China. Compared with results obtained by alternative polarization measurement scheme, following results can be obtained： the difference of relative amplitude measurement results is smaller than 2 dB and that of relative phase measurement results is smaller than 10？, verifying the validity of instantaneous polarization measurement scheme.

关键词： polarization scattering matrix alternative polarization measurement instantaneous polarization measurement field experiment.

Preconditioning method and engineering application of large eddy simulation

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Science China(Physics,Mechanics & Astronomy) 2008年第6期51卷 667-677页

作者： li xuesong XU JianZhong GU ChunWei Key Laboratory for Thermal Science and Power Engineering of Ministry of Education of China Depart-ment of Thermal EngineeringTsinghua UniversityBeijing 100084China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100080China

On applying large eddy simulation (LES) to engineering interest, one of the keys is to obtain two-order low-dissipation shock-capturing schemes adapted to LES. Therefore, the preconditioning method for all speed flows is adopted. However, the accuracy of preconditioned schemes is not satisfactory because of the poor per-formance of stability of preconditioning techniques especially in viscous flows. The reason of unstability is attributed to the unstability structure in the preconditioned eigenvalue matrix. Based on Roe scheme and two assumptions for low-Mach- Number flows, the new scheme named Low-Speed-Roe scheme is deduced for removing the unstability structure. Numerical experiments show that this scheme has the reasonable computational stability. For general-precision problems, Low-Speed-Roe scheme has similar behavior as the classical preconditioned Roe scheme. For simulations of high-accuracy requirement such as LES, Low-Speed- Roe scheme can obtain better results of complex flows, such as the laminar sepa-ration bubble on the suction surface of the high-loaded turbine blade T106.

关键词： preconditioning method eigenvalue matrix Low-Speed-Roe scheme large eddy simulation engineering application

Using ontology and rules to retrieve the semantics of disaster remote sensing data

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Journal of Systems Engineering and Electronics 2024年第5期35卷 1211-1218页

作者： DONG Yumin li Ziyang li xuesong li Xiaohui Key Laboratory of Quantitative Remote Sensing Information Technology Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

Remote sensing data plays an important role in natural disaster ***,with the increase of the variety and quantity of remote sensors,the problem of“knowledge barriers”arises when data users in disaster field retrieve remote sensing *** improve this problem,this paper proposes an ontology and rule based retrieval(ORR)method to retrieve disaster remote sensing data,and this method introduces ontology technology to express earthquake disaster and remote sensing knowledge,on this basis,and realizes the task suitability reasoning of earthquake disaster remote sensing data,mining the semantic relationship between remote sensing metadata and *** prototype system is built according to the ORR method,which is compared with the traditional method,using the ORR method to retrieve disaster remote sensing data can reduce the knowledge requirements of data users in the retrieval process and improve data retrieval efficiency.

关键词： remote sensing data disaster ontology semantic reasoning

A Recurrent Attention and Interaction Model for Pedestrian Trajectory Prediction

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1361-1370页

作者： xuesong li Yating liu Kunfeng Wang Fei-Yue Wang State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190and also with the University of Chinese Academy of SciencesBeijing 100049China College of Information Science and Technology Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China IEEE

The movement of pedestrians involves temporal continuity,spatial interactivity,and random *** a result,pedestrian trajectory prediction is rather *** existing trajectory prediction methods tend to focus on just one aspect of these challenges,ignoring the temporal information of the trajectory and making too many *** this paper,we propose a recurrent attention and interaction(RAI)model to predict pedestrian *** RAI model consists of a temporal attention module,spatial pooling module,and randomness modeling *** temporal attention module is proposed to assign different weights to the input sequence of a target,and reduce the speed deviation of different *** spatial pooling module is proposed to model not only the social information of neighbors in historical frames,but also the intention of neighbors in the current *** randomness modeling module is proposed to model the uncertainty and diversity of trajectories by introducing random *** conduct extensive experiments on several public *** results demonstrate that our method outperforms many that are state-ofthe-art.

关键词： Deep learning long short-term memory(LSTM) recurrent attention and interaction(RAI)model trajectory prediction

3D TRANSIENT COUPLED THERMOELASTIC-PLASTIC CONTACT SEAliNG ANALYSIS OF REACTOR PRESSURE VESSEL

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Chinese Journal of Mechanical Engineering 2005年第4期18卷 473-476页

作者： Du xuesong li Runfang lin Tengjiao State Key Laboratory of Mechanical Transmission Chongqing University Chongqing 400044 China

Sealing analysis of sealing system in reactor pressure vessels is relevant with multiple nonlinear coupled-field effects, so even large-scale commercial finite element software cannot finish the complicated analysis. A finite element method of 3D transient coupled thermo-elastic-plastic contact sealing analysis for reactor pressure vessels is presented, in which the surface nonlinearity, material nonlinearity, transient heat transfer nonlinearity and multiple coupled effect are taken into account and the sealing equation is coupling solved in iterative procedure. At the same time, a computational analysis program is developed, which is applied in the sealing analysis of experimental reactor pressure vessel, and the numerical results are in good coincidence with the experimental resuits. This program is also successful in analyzing the practical problem in engineering.

关键词： Pressure vessel Sealing analysis Finite element method

Asymptotical consensus of fractional-order multi-agent systems with current and delay states

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Applied Mathematics and Mechanics(English Edition) 2019年第11期40卷 1677-1694页

作者： Xuhui WANG xuesong li Nanjing HUANG D.O'REGAN Department of Mathematics Sichuan UniversityChengdu 610064China School of Mathematics Statistics and Applied MathematicsNational University of IrelandGalwayIreland

In this paper,we study some new fractional-order multi-agent systems with current and delay states (FMASCD).Using the generalized Nyquist's stability criterion and Gerschgorin's circle theorem,we obtain the bounded input-bounded output (BIBO) stability and asymptotical consensus of the FMASCD under mild ***,we give some numerical examples to illustrate our main results.

关键词： fractional-order multi-agent system (FMAS) asymptotical consensus current state delay state

Robust control for active suspension system under steering condition

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Science China(Technological Sciences) 2017年第2期60卷 199-208页

作者： WANG ChunYan DENG Ke ZHAO WanZhong ZHOU Guan li xuesong Department of Automotive Engineering Nanjing University of Aeronautics and Astronautics State Key Laboratory of Automobile Simulation and Control Jilin University

To minimize the auto body's posture change caused by steering and uneven road, and improve the vehicle's riding comfort and handling stability, this paper presents an H∞ robust controller of the active suspension system, which considers the effects of different steering conditions on its dynamic performance. The vehicle's vibration in the yaw, roll, pitch and vertical direction and the suspension's dynamic deflection in the steering process are taken into account for the designed H∞ robust controller, and it introduces the frequency weight function to improve the riding comfort in the specific sensitive frequency bands to human body. The proposed robust controller is testified through simulation and steering wheel angle step test. The results show that the active suspension with the designed robust controller can enhance the anti-roll capability of the vehicle, inhibit the changes of the body, and improve the riding comfort of the vehicle under steering condition. The results of this study can provide certain theoretical basis for the research and application of active suspension system.

关键词： vehicle active suspension system steering condition H∞ robust control sensitive frequency bands