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Journal of Shanghai Jiaotong university(Science) 2016年第3期21卷 297-306页

作者：王余奎黄之杰赵徐成朱毅魏东涛 air force Logistics college of pla Xuzhou 221000JiangsuChina Ordnance Engineering college of pla Shijiazhuang 050003China

Aiming at the existing problems of discrete cosine transform(DCT) de-noising method, we introduce the idea of wavelet neighboring coefficients(WNC) de-noising method, and propose the cosine neighboring coefficients(CNC) de-noising method. Based on DCT, a novel method for the fault feature extraction of hydraulic pump is analyzed. The vibration signal of pump is de-noised with CNC de-noising method, and the fault feature is extracted by performing Hilbert-Huang transform(HHT) to the output signal. The analysis results of the simulation signal and the actual one demonstrate that the proposed CNC de-noising method and the fault feature extraction method have more superior ability than the traditional ones.

关键词： discrete cosine transform(DCT) de-noising method cosine neighboring coefficients(CNC) de-noising method hydraulic pump fault feature extraction

Antlion optimizer algorithm based on chaos search and its application

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Journal of Systems Engineering and Electronics 2019年第2期30卷 352-365页

作者： ZHANG Zhenxing YANG Rennong LI Huanyu FANG Yuhuan HUANG Zhenyu ZHANG Ying air Traffic Control and Navigation college Air Force Engineering University Unit 95939 of pla

Aiming at the problems of premature convergence and easily falling into local optimums of the antlion optimization algorithm, a chaos antlion optimization algorithm based on the chaos search is proposed. Firstly, in the algorithm, the population is initialized by using the tent chaotic mapping, and the self-adaptive dynamic adjustment of chaotic search scopes is proposed in order to improve the overall fitness and the optimization efficiency of the population. Then, the tournament strategy is used to select antlions. Finally, the logistic chaos operator is used to optimize the random walk of ants, which forms a global and local parallel search mode with the antlion’s foraging behavior. The performance algorithm is tested through 13 complex high-dimensional benchmark functions and three dimensional path planning problems. The experimental results of six complex high-dimensional benchmark functions show that the presented algorithm has a better convergence speed and precision than the standard antlion algorithm and other optimization algorithms, and is suitable for the optimization of complex high dimensional functions. The trajectory planning experimental results show that compared with the antlion optimizer(ALO) algorithm, grey wolf optimizer(GWO), particle swarm optimization(PSO) and artificial bee colony(ABC) algorithm, it has advantages in speed and accuracy to obtain a specific path, and it is of great value in actual problems.

关键词： antlion optimizer(ALO) algorithm chaos theory tent mapping tournament selection strategy logistic mapping path planning

Robust structured total least squares algorithm for passive location

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Journal of Systems Engineering and Electronics 2015年第5期26卷 946-953页

作者： Hao Wu Shuxin Chen Yihang Zhang Hengyang Zhang Juan Ni Information and Navigation college Air Force Engineering University Unit 94303 of pla

A new approach called the robust structured total least squares(RSTLS) algorithm is described for solving location inaccuracy caused by outliers in the single-observer passive location. It is built within the weighted structured total least squares(WSTLS)framework and improved based on the robust estimation ***, the improved Danish weight function is proposed according to the robust extremal function of the WSTLS, so that the new algorithm can detect outliers based on residuals and reduce the weights of outliers automatically. Finally, the inverse iteration method is discussed to deal with the RSTLS problem. Simulations show that when outliers appear, the result of the proposed algorithm is still accurate and robust, whereas that of the conventional algorithms is distorted seriously.

关键词： passive location structured total least squares robust estimation equivalent weight function

Hybrid Particle Swarm Optimization Algorithm Based on Entropy Theory for Solving DAR Scheduling Problem

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Tsinghua Science and Technology 2019年第3期24卷 281-290页

作者： Haowei Zhang Junwei Xie Jiaang Ge Junpeng Shi Zhaojian Zhang air and Missile Defense college Air Force Engineering University National University of Defense Technology (NUDT) air force Early Warning Academy of pla

An efficient task-scheduling algorithm in the Digital Array Radar(DAR) is essential to ensure that it can handle a large number of requested tasks simultaneously. As a solution to this problem, in this paper, we propose an optimization model for scheduling DAR tasks using a hybrid approach. The optimization model considers the internal task structure and the DAR task-scheduling characteristic. The hybrid approach integrates a particle swarm optimization algorithm with a genetic algorithm and a heuristic task-interleaving algorithm. We introduce the chaos theory to optimize initialized particles and use entropy theory to indicate the diversity of particles and adaptively adjust the inertia weight, the crossover probability, and the mutation probability. Then, we improve both the efficiency and global exploration ability of the hybrid algorithm. In the framework of the swarm exploration algorithm, we include a heuristic task-interleaving scheduling algorithm, which not only utilizes the wait interval to transmit or receive subtasks, but also overlaps the receive intervals of different tasks. In a large-scale simulation,we demonstrate that the proposed algorithm is more robust and effective than existing algorithms.

关键词： digital array radar task scheduling particle swarm optimization

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： Tong Li Quhan Cheng Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu Tang Zhongyang Liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of Training and Sports Medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina Medical School of Chinese pla BeijingChina Key Laboratory of Bioactive Materials for the Ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation Medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

Design and Simulation of Solid State Pulser with Fast Rise Time and Double-exponential Waveform

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高电压技术 2014年第1期40卷 237-241页

作者： YANG Qingxi WANG Qingguo ZHOU Xing ZHAO Min ZHANG Yongqiang Institute of Electrostatic and Electromagnetic Protection Mechanical Engineering College Shijiazhuang050003 China shijiazhuang flying college of the pla air force Shijiazhuang 050081 China

Voltage pulses with fast rise time can be obtained from Marx circuits based on avalanche transistors. In this research, the ZETEX avalanche transistors are used as the switches in a Marx circuit to generate stable voltage pulses with double-exponential waveform and fast rise time. By using these transistors, the circuit is able to generate higher pulsed voltage with fewer stages. A three stages and a ten stages Marx circuit, as well as their triggering circuits, are designed. The two Marx circuits are also tested by simulations based on the Pspice code and by experiments, results of which are consistent with each other. With the ten stages Marx circuit, we obtain positive and negative pulses with the rise time of about 1.5 ns, the amplitude above 1 100 V, and the pulse width below 5 ns. It is proved that the proposed Marx circuit equipped with avalanche transistors could be an effective kind of solid-state pulse generator.

关键词：脉冲发生器电路设计上升时间波形固态雪崩晶体管仿真 Pspice

Finite sensor selection algorithm in distributed MIMO radar for joint target tracking and detection

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Journal of Systems Engineering and Electronics 2020年第2期31卷 290-302页

作者： ZHANG Haowei XIE Junwei GE Jiaang ZHANG Zhaojian LU Wenlong air and Missile Defense college Air Force Engineering UniversityXi’an 710051China air force Early Warning Academy of the pla Wuhan 410039China Unit 95899 of the pla Beijing 100085China

Due to the requirement of anti-interception and the limitation of processing capability of the fusion center, the subarray selection is very important for the distributed multiple-input multiple-output(MIMO) radar system, especially in the hostile environment. In such conditions, an efficient subarray selection strategy is proposed for MIMO radar performing tasks of target tracking and detection. The goal of the proposed strategy is to minimize the worst-case predicted posterior Cramer-Rao lower bound(PCRLB) while maximizing the detection probability for a certain region. It is shown that the subarray selection problem is NP-hard, and a modified particle swarm optimization(MPSO) algorithm is developed as the solution strategy. A large number of simulations verify that the MPSO can provide close performance to the exhaustive search(ES) algorithm. Furthermore, the MPSO has the advantages of simpler structure and lower computational complexity than the multi-start local search algorithm.

关键词： distributed multiple-input multiple-output(MIMO)radar subarray selection target tracking target detection particle swarm optimization(PSO)

The stochastic sliding mode variable structure guidance laws based on optimal control theory

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控制理论与应用（英文版） 2013年第1期11卷 86-91页

作者： Hongqiang WANG Daiqiang CAO Xudong WANG pla 95997 Unit Engineering college Air Force Engineering University

A stochastic sliding-mode variable structure guidance law involving optimal control theory is presented for the missile target intercept model, in which state noise, uncertain system parameters, target movement and measured noise are considered. This guidance law synthesizes the merits of optimal guidance law with line-of-sight rate convergence and sliding-mode guidance law with strong robustness. Through theoretic analysis, it is proved that the sliding mode hyperplane is sub-achievable in the closed loop system. The numerical results show the effectiveness of the proposed control algorithm.

关键词： Stochastic system Variable structure control Optimal control Guidance law Robust

Approach for air-to-air confrontment based on uncertain interval information conditions

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Journal of Systems Engineering and Electronics 2019年第1期30卷 100-109页

作者： LI Qiuni YANG Rennong FENG Chao LIU Zongcheng Aeronautics and Astronautics Engineering college Air Force Engineering University Unit 66133 of the pla

Model combat information conditions are always uncertain and varied, the uncertain interval theory is therefore introduced into the research of multiple fighters suppressing the integrated air defense system(IADS) problem. Considering that the combat information conditions are uncertain intervals, the payoff function of the game for multiple fighters suppressing the IADS is *** the operation rules for interval numbers and the possibility degree, an improved chaotic particle swarm optimization(CPSO)is designed to solve the proposed model so as to obtain the optimal game solution. Comparison simulations are performed to analyze the influence of the weapons consumption and the distances of non-escaped zone and jamming on air combat result. Simulation results suggest that Nash equilibrium is achieved and verify the effectiveness of the proposed method.

关键词： interval information integrated air defense system (IADS) air combat chaotic particle swarm optimization (CPSO) game.

Analysis of High-Frequency EM Scattering Properties on Time-Varying Sea Surface

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Chinese Journal of Electronics 2016年第2期25卷 384-390页

作者： LI Changze TONG Chuangming QI Lihui WANG Tong ZHAO Haizhou air and Missile Defense college Air Force Engineering University Military Representative Office of pla in 786 Factory

This paper proposes to solve the extralarge scale Electromagnetic(EM) scattering problem on a wind-driven sea surface at Low-grazing-angle(LGA) directed against a shore-based radar with an Iterative physical optics(IPO) model. Using Monte Carlo simulations,it compares the average Doppler spectra of backscattered signals at different angles and sea states. The methods are: the forward-backward methodology and its modification with under-relaxation iteration which improves convergence and stability of the IPO; the local iteration methodology and the Fast far-field approximation(Fa FFA)in the matrix-vector product which reduce the computational complexity based on the scattering characteristics of sea surface. The simulations show a broadening effect of the Doppler spectra in a more complicated sea state at LGA.

关键词： Shore-based radar Doppler spectra LGA Iterative model Forward-backward methodology