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An Amphibious Vehicle Modeling and Maneuvering Path planning Method Suitable for Military Topographic Maps

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Wuhan University Journal of Natural Sciences 2020年第6期25卷 538-546页

作者： LIU Yu ZHANG Wei XU Shengliang Teaching and Research Department of unit 91976 PLAGuangzhouGuangdong 510430China

Path planning of amphibious vehicles on military topographic maps is a hot research topic in the field of amphibious tactical training *** to the dynamic characteristics and maneuvering destination requirements of amphibious vehicles,a three-dimensional simulation model of amphibious vehicles is designed,and a straight-line driving and steering dynamic model is *** optimal maneuvering destination and constraint conditions under the condition of unconnected graph are put forward,and the problems of simulation and maneuvering path planning of amphibious vehicles on unconnected graph are solved by the theory of region partition and shortest path of *** with Dijkstra algorithm and heuristic algorithm A~*,the experimental results show that the algorithm designed in this paper has superior applicability and time performance.

关键词： amphibious vehicles multi-objective decision making shortest path combat training simulation model

A data transmission scheduling algorithm for rapid-response earth-observing operations

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Chinese Journal of Aeronautics 2014年第2期27卷 349-364页

作者： Li Jun Li Jun Chen Hao Jing Ning College of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China unit 61726 PLA Wuhan 430074 China

With the development of rapid-response Earth-observing techniques, the demand for reducing a requirements-tasking-effects cycle from 1 day to hours grows rapidly. For instance, a satellite user always wants to receive requested data in near real-time to support their urgent mis- sions, such as dealing with wildfires, volcanoes, flooding events, etc. In this paper, we try to reduce data transmission time for achieving this goal. The new feature of a responsive satellite is that users can receive signals from it directly. Therefore, the traditional satellite control and operational tech- niques need to be improved to accommodate these changes in user needs and technical upgrading. With that in mind, a data transmission topological model is constructed. Based on this model, we can deal with the satellite data transmission problem as a multi-constraint and multi-objective path- scheduling problem. However, there are many optional data transmission paths for each target based on this model, and the shortest path is preferred. In addition, satellites represent scarce resources that must be carefully scheduled in order to satisfy as many consumer requests as possible. To efficiently balance response time and resource utilization, a K-shortest path genetic algorithm is proposed for solving the data transmission problem. Simulations and analysis show the feasibility and the adaptability of the proposed approach.

关键词： Data transmission in nearreal-time Genetic algorithm K-shortest path Operationally responsivespace Remote sensing Scheduling

User-oriented data acquisition chain task planningalgorithm for operationally responsive space satellite

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Journal of Systems Engineering and Electronics 2016年第5期27卷 1028-1039页

作者： Hao Chen Jun Li Ning Jing Jun Li College of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073China unit 61726 of the pla Wuhan 430074China

With the development of operationally responsive space（ORS） and on-board processing techniques, the end users canreceive the observation data from the ORS satellite directly. Tosatisfy the demand for reducing the requirements-tasking-effectscycle from one day to hours, the various resources of the wholedata acquisition chain （including satellites, ground stations, dataprocessing centers, users, etc.） should be taken into an overallconsideration, and the traditional batch task planning mode shouldbe transformed into the user-oriented task planning mode. Consideringthere are many approaches for data acquisition due tothe new techniques of ORS satellite, the data acquisition chaintask planning problem for ORS satellite can be seen as the multimodalroute planning problem. Thereby, a framework is presentedusing label-constrained shortest path technique with the conflictresolution. To apply this framework to solve the ORS satellite taskplanning problem, the preprocessing and the conflict resolutionstrategies are discussed in detail. Based on the above work, theuser-oriented data acquisition chain task planning algorithm forORS satellite is proposed. The exact solution can be obtainedin polynomial time using the proposed algorithm. The simulationexperiments validate the feasibility and the adaptability of the proposedapproach.

关键词： operationally responsive space (ORS) remote sensing,scheduling multi-modal route planning shortest path computationalcomplexity.

Differential geometric guidance command with finite time convergence using extended state observer

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Journal of Central South University 2016年第4期23卷 859-868页

作者：麻毅威张为华 College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China unit 61541 of pla Beijing 100094China

For improving the performance of differential geometric guidance command(DGGC), a new formation of this guidance law is proposed, which can guarantee the finite time convergence(FTC) of the line of sight(LOS) rate to zero or its neighborhood against maneuvering targets in three-dimensional(3D) space. The extended state observer(ESO) is employed to estimate the target acceleration, which makes the new DGGC more applicable to practical interception scenarios. Finally, the effectiveness of this newly proposed guidance command is demonstrated by the numerical simulation results.

关键词： missile guidance differential geometric guidance command (DGGC) finite time convergence (FTC) extended state observer (ESO) maneuvering targets

Optimal midcourse trajectory cluster generation and trajectory modification for hypersonic interceptions

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1162-1173页

作者： Humin Lei Jin Zhou Dailiang Zhai Lei Shao Dayuan Zhang Air and Missile Defense College Air Force Engineering University Xi’an 710051 China unit 95948 of the pla Jiuquan 732750 China

The hypersonic interception in near space is a great challenge because of the target’s unpredictable trajectory, which demands the interceptors of trajectory cluster coverage of the predicted area and optimal trajectory modification capability aiming at the consistently updating predicted impact point(PIP) in the midcourse phase. A novel midcourse optimal trajectory cluster generation and trajectory modification algorithm is proposed based on the neighboring optimal control theory. Firstly, the midcourse trajectory optimization problem is introduced; the necessary conditions for the optimal control and the transversality constraints are ***, with the description of the neighboring optimal trajectory existence theory(NOTET), the neighboring optimal control(NOC)algorithm is derived by taking the second order partial derivations with the necessary conditions and transversality conditions. The revised terminal constraints are reversely integrated to the initial time and the perturbations of the co-states are further expressed with the states deviations and terminal constraints ***, the simulations of two different scenarios are carried out and the results prove the effectiveness and optimality of the proposed method.

关键词： neighboring optimal control(NOC) midcourse guidance trajectory cluster generation optimal trajectory modification

Motion compensation algorithm in narrowband imaging for mid-course targets

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Journal of Systems Engineering and Electronics 2017年第1期28卷 40-50页

作者： Xizhang Wei Zhen Liu Xiaofeng Ding Bo Peng School of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073China unit 31006 of the pla Beijing 100086China

Imaging precession targets based on the narrowband radar to distinguish the real warhead from mid-course targets is a new technique in missile defense systems. Aiming at the typical mid-course flying scene, this paper describes the principle of the narrowband imaging method, and analyzes the influence on the narrowband imaging by the target translational motion. Then the precision qualification is deduced for both the distance compensation and the velocity compensation, and the conclusion that the velocity compensation is more appropriate for the motion compensation in the narrowband imaging is given. Furthermore, this paper proposes a motion compensation algorithm for the narrowband radar which reduces the interference of the signal phase chaos caused by the rebuilt real signal phase, thus realizing the precise translational motion compensation of the narrowband signal. Finally, the effectiveness of this method is proved by both theoretic analysis and experiment results. © 1990-2011 Beijing Institute of Aerospace Information.

关键词： Radar Radar imaging

An expert consensus on the evaluation and treatment of acute thoracolumbar spine and spinal cord injury in China

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Neural Regeneration Research 2013年第33期8卷 3077-3086页

作者： Zhicheng Zhang Fang Li Tiansheng Sun pla Institute of Orthopedics Beijing Army General Hospital of Chinese PLA

This is an expert consensus on the evaluation and treatment of thoracolumbar spinal injury, estab- lished from February 2009 to July 2010. The expert consensus consists mainly of six parts with a total of 54 recommendations including the overview （one item）; pre-hospital care （one item）; evaluation and diagnosis （13 items）; treatment （23 items）; prevention and treatment of major com- plications （12 items）; and rehabilitation （four items）. This is the first time that Chinese experts have published a consensus on spine and spinal cord injury. The expert consensus was established based on Delphi methods, literature analysis, and clinical experiences. Each recommendation is supported by and was interpreted using multi-level evidences. The level of agreement with the rec- ommendation among the panel members was assessed as either low, moderate, or strong. Each panel member was asked to indicate his or her level of agreement on a 5-point scale, with ＂1＂ cor- respondJng to neutrality and ＂5＂ representJng maxJmum agreement. Scores were aggregated across the panel members and an arithmetic mean was calculated. This mean score was then translated into low, moderate, or strong. After all of the votes were collected and calculated, the results showed no low-level recommendations, 10 moderate-level recommendations, and 44 strong-level recom- mendations. An expert consensus was reached and was recognized by Chinese spine surgeons. Wide-scale adoption of these recommendations is urgent in the management of acute thora- columbar spine and spinal cord injury in a broader attempt to create a standard evaluation and treatment strategy for acute thoracolumbar spine and spinal cord injury in China.

关键词： neural regeneration spinal cord injury expert consensus thoracolumbar spine and spinal cord injury guidelines evidence-based medicine neurological function diagnosis treatment rehabilitation grant-supported paper neuroregeneration

Analysis of Two Public Key Cryptosystems Based on Randomized Knapsack Sequences

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Chinese Journal of Electronics 2014年第1期23卷 175-178页

作者： PENG Liqiang ZUO Jinyin HU Lei XU Jun State Key Laboratory of Information Security Institute of Information Engineering Chinese Academy of Sciences pla unit 95899

Two knapsack public key cryptosystems based on randomized knapsack sequences were proposed in2009 and 2011 respectively, where the secret knapsack sequence is transformed by secret modular linear transforms into one or three public randomized knapsack sequences with appropriate density. In this paper, we recover the secret modular linear transforms by simultaneous Diophantine approximation and propose secret key recovery attacks on these two cryptosystems. Practical attack experiments are done within one minute.

关键词： Knapsack public key cryptosystem Simultaneous Diophantine approximation Lattice L3 algorithm

Degradation Mechanism of Lacquered Tinplate in Energy Drink by in-situ EIS and EN

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Journal of Wuhan University of Technology(Materials Science) 2013年第2期28卷 367-372页

作者：周超 WANG Jihui SONG Shizhe 夏大海 WANG Ke SHEN Chen LUO Bing SHI Jiangbo School of Materials Science and Engineering Tianjin University Department of Chemical and Materials Engineering University of Alberta 94277 unit of the pla

The corrosion process of phenolic epoxy coated tinplate in energy drink was investigated by in-situ electrochemical impedance spectroscopy（EIS） and electrochemical noise（EN） techniques. The experimental results indicate that the degradation process of novolac epoxy coated tinplate in energy drink can be divided into three main stages： organic coating wetted by the beverage; corrosion initiation beneath the organic coating; and corrosion extension process. It was proposed that the tin coating and carbon steel were mainly corroded by organic acids in energy drink through the pores of the organic coating. After the tin coating was corroded, the carbon steel started to corrode due to its higher electrochemical activity and became to be the dominated corrosion reaction.

关键词： tinplate energy drink electrochemical impedance spectroscopy electrochemical noise corrosion mechanism