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An efficient adaptive space partitioning algorithm for electromagnetic scattering calculation of complex 3D models

Journal of systems Engineering and Electronics 2021年第5期32卷 1071-1082页

作者： HUANG Minjie ZHOU Yaoming WANG Yongchao LIU Zhongtie School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Complex Aviation System Simulation Beijing 100076China

The space partitioning algorithm based on the rounding and addressing operations has been proved to be an efficient space partitioning algorithm with the potential for real-time *** improvement on this kind of space partitioning algorithms for solving complex 3D models is *** examples show that the efficiency of the improved algorithm is better than that of the original *** the size of most target elements is smaller than the size of spatial grids,the efficiency of the improved method can be more than four times of that of the original *** adaptive method of space partitioning based on the improved algorithm is developed by taking the surface element density or the curvature as the threshold for deep partitioning and conducting the deep partitioning using the octree method.A computer program implementation for applying the method in some typical applications is discussed,and the performance in terms of the efficiency,reliability,and resource use is *** testing shows that the results of the adaptive spacing partitioning are more convenient for the follow-up use than that of the basic uniform space ***,when it is used to calculate the electromagnetic scattering of complex targets by the ray tracing(RT)method,the adaptive space partitioning algorithm can reduce the calculation time of the RT process by more than 40%compared with the uniform space segmentation algorithm.

关键词： adaptive space partitioning computer graphics binary space partitioning ray tracing(RT)method stealth technology

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Scattering Center Modeling Using Adaptive Segmental Compressive Sampling

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Journal of Beijing Institute of technology 2017年第4期26卷 484-493页

作者： Qifeng Li Kunyi Guo Jiaxin Wang Xinqing Sheng Tianshu Liu Center for Electromagnetic Simulation School of Information and ElectronicsBeijing Institute of Technology Science and Technology on Special System Simulation Laboratory Beijing Simulation Center

In order to deal with aliasing distortions of Doppler frequencies shown in time-frequency representation（ TFR） with aspect undersampling,an approach using adaptive segmental compressive sampling according to the aspect dependencies of the scattering centers is proposed. The random noise problem induced by compressive sampling is solved by employing a series of signal processing techniques of filtering,image transformation and Hough Transform. Three examples are presented to verify the effectiveness of this approach. The comparisons between the built models and the precise scattered fields computed by a well-validated full-wave numerical method are investigated,and the results showgood agreements between each other.

关键词： scattering center undersampling compressive sensing time-frequency representation parameter estimation

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Application of Topology Analysis in Visualization of 2D Dynamic Vector Fields 7

Application of Topology Analysis in Visualization of 2D Dyna...

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2016 IEEE 7th International Conference on Software Engineering and Service science

作者： Li Chao Wu Lingda Zhao Bin Science and Technology on Complex Electronic System Simulation Laboratory Equipment Academy Electronic Equipment Test Center

ISBN: (纸本)9781467399050

Flow is one of the most fundamental physical process in natural *** visualization can give an intuitive view of flow fields and contribute to the observation and analysis of *** flow fields are all dynamic while traditional visualization approaches are not able to reflect the trends of flows or the diversity inside *** on the research of Lagrangian Coherent Structures in Computational Fluid Dynamics,the concept of flow field topology is redefined,two typical 2D dynamic vector fields are selected for topology analysis,and the results are used to optimize the visual effects of geometric *** show that visualization of 2D dynamic vector fields based on topology analysis can extract the coherent structures of flows which are helpful to the comprehension of flow for researchers and description of characteristic difference inside flows.

关键词： flow visualization topology analysis dynamic flow fields vector fields Lagrangian Coherent Structures

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Data-Centered Computing and Implementation in Web Service 7

Data-Centered Computing and Implementation in Web Service

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2016 IEEE 7th International Conference on Software Engineering and Service science

作者： Li Chao Wu Lingda Zhao Bin Science and Technology on Complex Electronic System Simulation Laboratory Equipment Academy Electronic Equipment Test Center

ISBN: (纸本)9781467399050

Parallel computer architectures bring synchronization problem which bog down the *** the speed gap between CPU and memory keeps growing,making data operation more *** some data-intensive applications,there are similar or coincident child operations in parallel threads,which take unnecessary *** effectively exploit parallelization,reduce the price of data operation,the concept of data-centered computing is *** considering the similarity and relations between data and merging them into unions as threads' input,data-centered computing can eliminate data operation redundancy of data-intensive *** implementation in web service proves that data-centered computing can effectively improve performance.

关键词： data-centered web service data vector parallelization

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Symplectic Wigner Distribution in the Linear Canonical Transform Domain: Theory and Application

arXiv

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arXiv 2025年

作者： He, Yangfan Zhang, Zhichao School of Communication and Artificial Intelligence School of Integrated Circuits Nanjing Institute of Technology Nanjing211167 China School of Mathematics and Statistics Nanjing University of Information Science and Technology Nanjing210044 China Key Laboratory of System Control and Information Processing Ministry of Education Shanghai Jiao Tong University Shanghai200240 China Key Laboratory of Computational Science Application of Hainan Province Hainan Normal University Haikou571158 China Key Laboratory of Numerical Simulation of Sichuan Provincial Universities School of Mathematics and Information Sciences Neijiang Normal University Neijiang641000 China

This paper devotes to combine the chirp basis function transformation and symplectic coordinates transformation to yield a novel Wigner distribution (WD) associated with the linear canonical transform (LCT), named as the symplectic WD in the LCT domain (SWDL). It incorporates the merits of the symplectic WD (SWD) and the WD in the LCT domain (WDL), achieving stronger capability in the linear frequency-modulated (LFM) signal frequency rate feature extraction while maintaining the same level of computational complexity. Some essential properties of the SWDL are derived, including marginal distributions, energy conservations, unique reconstruction, Moyal formula, complex conjugate symmetry, time reversal symmetry, scaling property, time translation property, frequency modulation property, and time translation and frequency modulation property. Heisenberg’s uncertainty principles of the SWDL are formulated, giving rise to three kinds of lower bounds attainable respectively by Gaussian enveloped complex exponential signal, Gaussian signal and Gaussian enveloped chirp signal. The optimal symplectic matrices corresponding to the highest time-frequency resolution are generated by solving the lower bound optimization (minimization) problem. The time-frequency resolution of the SWDL is compared with those of the SWD and WDL to demonstrate its superiority in LFM signals time-frequency energy concentration. A synthesis example is also carried out to verify the feasibility and reliability of the theoretical analysis. Copyright © 2025, The Authors. All rights reserved.

关键词： Wigner-Ville distribution

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Joint Secure and Covert Communications for Active STAR-RIS Assisted ISAC systems

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IEEE Transactions on Wireless Communications 2025年

作者： Guo, Liang Jia, Jie Mu, Xidong Liu, Yuanwei Chen, Jian Wang, Xingwei Northeastern University School of Computer Science and Engineering China Northeastern University Engineering Research Center of Security Technology of Complex Network System Ministry of Education China Northeastern University Key Laboratory of Intelligent Computing in Medical Image Ministry of Education Shenyang110819 China BelfastBT3 9DT United Kingdom Department of Electrical and Electronic Engineering China

This paper investigates the design of jointly supporting physical layer security (PLS) and covert communications (CCs) in an active simultaneously transmitting and reflecting reconfigurable intelligent surface (a-STAR-RIS) assisted integrated sensing and communication (ISAC) system. Due to the unified waveform design of ISAC signals, we consider a challenging scenario with two targets being suspicious attackers, where one warden target potentially detects the confidential transmission behavior of covert users and another eavesdropper target attempts to intercept the broadcasted confidential information of security users. We investigate the joint beamforming design at the base station (BS) and the a-STAR-RIS to achieve a high-quality sensing beampattern while meeting covertness and security communication requirements. (1) For the ideal scenario with perfect channel state information (CSI) and precise target locations, we propose an alternative optimization (AO) method to address the optimization problem involving highly coupled variables. Specifically, the optimal beamforming design at the BS is handled using the semi-definite relaxation (SDR) technique, while the beamforming design at the a-STAR-RIS is addressed through a penalty-based iterative algorithm. (2) A more practical case with uncertain target locations and imperfect CSI is considered to achieve a robust beamforming design, where the non-deterministic outage probability constraints are effectively transformed by employing the Bernstein-type inequality. Numerical results demonstrate the superiority of the a-STAR-RIS over the baseline cases and certify that the proposed algorithms can effectively balance the tradeoff among the sensing quality, covert and secure communication requirements. Besides, results also show that the proposed robust beamforming scheme can construct adequate sensing beampattern, even with imperfect CSI and uncertain target locations. © 2002-2012 IEEE.

关键词： Beamforming

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Comparisons of STRETCH meat grinders based on two different topologies of ICCOS

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Journal of Beijing Institute of technology 2013年第4期22卷 432-439页

作者：刘辉毕世华李军刘培柱陈阵 School of Aerospace Engineering Beijing Institute of Technology Science and Technology on Complex Land Systems Simulation Laboratory

Inductive energy storage systems （IES）require opening switches which are technically much more difficult to realize than closing switches. Institute of Advanced technology （ IAT ） puts forward a meat grinder with an inductive pulse power topology called slow transfer of energy through capacitive hybrid （STRETCH）. In this topology, an integrated gate-commutated thyristor （IGCT） is capable of breaking the charging currents on the order of 4 kA, and it may encounter difficulties in expanding to higher energy systems. German-French Institute of Saint Louis （ISL） has developed a high-power opening switch based on standard high-power thyristors by using their so-called inverse current commutation with semiconductor devices （ICCOS） countercurrent commutation principle. Two topologies of the STRETCH meat grinder with ICCOS are analyzed. And they are compared based on the voltage across the main switch, the current multiplication factor and other aspects by u- sing Matlab simulations. The advantages and disadvantages of the two topologies are shown through the comparisons. Therefore a more suitable topology can be chosen for realistic applications accord- ing to their performances.

关键词： inductive pulse power supplies STRETCH meat grinder IGCT inverse current commu-tation with semiconductor devices （ICCOS） comparisons

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Research on the information system architecture design framework and reference resources of American Army 3

Research on the information System architecture design frame...

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3rd International Conference on Advanced Information science and system, AISS 2021

作者： Jian, Ping Space Engineering University Science and Technology Complex Electronic System Simulation Laboratory China

ISBN: (纸本)9781450385862

The concept of architecture is put forward by the US Army, which refers to the composition structure of the system and its mutual relationship, as well as the principles and guidelines guiding the design and development of the system. Architecture design technology and its reference resources have important theoretical and technical support for the top-level design of information system. Based on the analysis of architecture technology and function, this paper systematically studies the connotation and development history of the architecture design framework of the US army, and sorts out the main reference resources of the architecture design of the US army, such as the common joint task list, information system interoperability level model, joint technology architecture. It provides useful reference for the theoretical and technical research of information system top-level design. © 2021 ACM.

关键词： Information use

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AutolEncideraBased for High Spectral Dimensional Data Classification and Visualization 2

AutolEncideraBased for High Spectral Dimensional Data Classi...

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2nd IEEE International Conference on Data science in Cyberspace, DSC 2017

作者： Zhu, Jiang Wu, Lingda Hao, Hongxing Song, Xiaorui Lu, Yi Science and Technology on Complex Electronic System Simulation Laboratory Equipment Academy Beijing China

ISBN: (纸本)9781538615997

The classification and visualization for surface objects receives a great deal of attention for high spectral dimensional data processing. A lot of methods were proposed and applied in this problem over the past decade. Whereas most of them still exist some challenge issues, include pre-treatment fussily, features extraction simplify, larger data processing difficultly and classification inaccurately. To solve these problems, we propose a novel method bases on deep learning which combines maximum noise fraction (MNF) and multilayers auto-encoders. Thereinto, MNF is used to reduce the inherent spectral dimensionality of high spectral dimensional data;autoencoders and softmax logistic regression function are applied for extracting high-level features and visualizing types of objects. On the experiments, we compared with traditional linear SVM method by using a 200-bands AVIRIS dataset over Indian Pines and a 103-bands ROSIS dataset over Italy Pavia. The results indicate that the algorithm in paper statistically significantly improved the classification and visualization accuracies and efficiencies. © 2017 IEEE.

关键词： Visualization

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A Region Preference-based Optimization Algorithm for Satellite Mission Planning Problem 2

A Region Preference-based Optimization Algorithm for Satelli...

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2021 2nd International Conference on Modeling, Big Data Analytics and simulation, MBDAS 2021

作者： Xiong, Minghui Xiong, Wei Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University China

For the earth observation satellite mission planning problem, objectives such as observed target quantity, observation profit, energy consumption, image quality should be considered simultaneously, which is a many-objective optimization problem. Classical optimization-based mission planning algorithms obtain a set of non-dominated solutions in the entire search space, while only a single satisfy final plan is desired by decision maker. In this paper, a five-objective optimization model for satellite mission planning problem is constructed, then a region preference-based evolutionary algorithm, HMOEA-T, is applied to obtain the desired solutions. The decision makers describe the preference on each objective in target region form, then the algorithm guides a more detailed search within the preference region rather than the entire Pareto front. Comparative studies with preference-based methods (T-NSGA-III) and classical methods (NSGA-III) are conducted. We have exemplified the proposed method manage to obtain the solutions satisfying the mission planning preference and achieve better performance in convergence and diversity. © Published under licence by IOP Publishing Ltd.

关键词： Evolutionary algorithms

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