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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 181-195页

作者： Sheng Cao Hongyu Liu Jin Jiang Ke He Binghua Lv Hao Zhang Lujie Zhang Jingrong Meng Hao Deng xiaodong Niu Department of Mechanical Engineering College of EngineeringShantou UniversityShantou515063China China State Shipbuilding Co. Ltd.Huangpu Wenchong Shipbuilding Company Ltd.Guangzhou510715China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100080China Shantou Ruixiang Mould Co. Ltd.Shantou515041China military representative office x of unit 93147 Deyang618000China China National Erzhong Group Co. Deyang Wanhang Die Forging Co.Ltd.Deyang618013China

This work investigated the gradient microstructure evolution and tensile property of LPBF fabricated 15-5 precipitation hardening stainless steel in post-process direct ageing(DA)and solution treating&ageing(STA).The varied microstructures for austenite and small-sized oxide inclusions at different sample heights in the as-built(AB)condition was generally preserved after DA ***,austenite was almost disappeared,and oxide particle grew significantly after the STA *** a result,the tensile property differences in sample top and bottom for AB and DA conditions did not occur in the STA *** the influence of post-process heat treatment,the STA condition had the highest yield strength due to the highest volume fraction of nano-sized Cu ***,the DA specimen had the highest ultimate tensile strength and elongation owing to the considerable amount of austenite phase and associated transformation induced plasticity effect.

关键词： 15-5 PH stainless steel Laser powder bed fusion Heat treatment Gradient microstructures Tensile properties

Real-time UAV path planning based on LSTM network

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Journal of Systems Engineering and Electronics 2024年第2期35卷 374-385页

作者： ZHANG Jiandong GUO Yukun ZHENG Lihui YANG Qiming SHI Guoqing WU Yong School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China The Flight Automatic Control Research Institute of AVIC Xi’an 710065China military representative office of Marine Wuhan Bureau in Luoyang Area Luoyang 471000China

To address the shortcomings of single-step decision making in the existing deep reinforcement learning based unmanned aerial vehicle(UAV)real-time path planning problem,a real-time UAV path planning algorithm based on long shortterm memory(RPP-LSTM)network is proposed,which combines the memory characteristics of recurrent neural network(RNN)and the deep reinforcement learning *** networks are used in this algorithm as Q-value networks for the deep Q network(DQN)algorithm,which makes the decision of the Q-value network has some *** to LSTM network,the Q-value network can use the previous environmental information and action information which effectively avoids the problem of single-step decision considering only the current ***,the algorithm proposes a hierarchical reward and punishment function for the specific problem of UAV real-time path planning,so that the UAV can more reasonably perform path *** verification shows that compared with the traditional feed-forward neural network(FNN)based UAV autonomous path planning algorithm,the RPP-LSTM proposed in this paper can adapt to more complex environments and has significantly improved robustness and accuracy when performing UAV real-time path planning.

关键词： deep Q network path planning neural network unmanned aerial vehicle(UAV) long short-term memory(LSTM)

Anti-interference self-alignment algorithm by attitude optimization estimation for SINS on a rocking base

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Journal of Systems Engineering and Electronics 2023年第5期34卷 1333-1342页

作者： xUE Haijian WANG Tao CAI xinghui WANG Jintao LIU Fei High-Tech Institute of xi’an Xi’an 710025China military representative office of Rocket Army Equipment Department Qingdao 266071China

The performance of a strapdown inertial navigation system(SINS)largely depends on the accuracy and rapidness of the initial alignment.A novel anti-interference self-alignment algorithm by attitude optimization estimation for SINS on a rocking base is presented in this *** algorithm transforms the initial alignment into the initial attitude determination problem by using infinite vector observations to remove the angular motions,the SINS alignment is heuristically established as an optimiza-tion problem of finding the minimum *** order to further improve the alignment precision,an adaptive recursive weighted least squares(ARWLS)curve fitting algorithm is used to fit the translational motion interference-contaminated reference vectors according to their time domain *** studies and experimental results favorably demonstrate its rapidness,accuracy and robustness.

关键词： strapdown inertial navigation system(SINS) initial alignment anti-interference rocking base adaptive recursive weighted least squares(ARWLS)

Situational continuity-based air combat autonomous maneuvering decision-making

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Defence Technology(防务技术) 2023年第11期29卷 66-79页

作者： Jian-dong Zhang Yi-fei Yu Li-hui Zheng Qi-ming Yang Guo-qing Shi Yong Wu School of Electronics and Information Northwestern Polytechnical UniversityXi'an710129China military representative office of Haizhuang Wuhan Bureau in Luoyang Region 471000China

In order to improve the performance of UAV's autonomous maneuvering decision-making,this paper proposes a decision-making method based on situational *** algorithm in this paper designs a situation evaluation function with strong guidance,then trains the Long Short-Term Memory(LSTM)under the framework of Deep Q Network(DQN)for air combat maneuvering *** the continuity between adjacent situations,the method takes multiple consecutive situations as one input of the neural *** reflect the difference between adjacent situations,the method takes the difference of situation evaluation value as the reward of reinforcement *** different scenarios,the algorithm proposed in this paper is compared with the algorithm based on the Fully Neural Network(FNN)and the algorithm based on statistical principles *** results show that,compared with the FNN algorithm,the algorithm proposed in this paper is more accurate and *** with the algorithm based on the statistical principles,the decision-making of the algorithm proposed in this paper is more efficient and its real-time performance is better.

关键词： UAV Maneuvering decision-making Situational continuity Long short-term memory(LSTM) Deep Q network(DQN) Fully neural network(FNN)

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导弹战斗部装药质量监督要点研究

兵工自动化 2024年第1期43卷 23-25页

作者：张斌宏曾燚王保刘影中国人民解放军93147部队重庆代表室重庆402760

针对导弹战斗部装药质量监督的实际需求,分析目前战斗部典型装药工艺方法(熔铸装药、压装药、PBx浇注装药)的特点。经过对比分析,结合导弹战斗部的发展需求,提出装药质量监督要点,为战斗部装药质量监督拟定较详细的控制措施。结果表明:... 详细信息

针对导弹战斗部装药质量监督的实际需求,分析目前战斗部典型装药工艺方法(熔铸装药、压装药、PBx浇注装药)的特点。经过对比分析,结合导弹战斗部的发展需求,提出装药质量监督要点,为战斗部装药质量监督拟定较详细的控制措施。结果表明:该质量监督要点及控制措施,可有效指导相关人员把控战斗部装药质量,提高监管效能。

关键词：导弹战斗部质量战斗部装药监管

Trajectory optimisation in electrical discharge machining of three-dimensional curved and twisted channels

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Chinese Journal of Aeronautics 2022年第4期35卷 473-484页

作者： Jianshe ZHAO Yicong QIU Jian YUAN Chao LIU College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Laboratory of Integrated Electrical Processing Nanjing HANGPU Machinery Technology Company LimitedNanjing 210000China military representative Bureau of the Air Force Equipment Department in Shanghai and military representative office in Zhuzhou Region Zhuzhou 412002China AECC South Industry Company Limited Zhuzhou 412002China

Numerical control electrical discharge machining(NC EDM) is one of the most widely used machining technologies for manufacturing a closed blisk flow path, particularly for three-dimensional(3D) curved and twisted flow channels. In this process, tool electrode design and machining trajectory planning are the key factors affecting machining accessibility and efficiency. Herein, to reduce the difficulty in designing the electrode and its motion path in the closed curved and twisted channels, a heuristic search hybrid optimisation strategy based on channel grids is adopted to realise the initial electrode trajectory design search and optimised size reduction. By transferring the trajectory optimisation constraints from the complex free-form surface to numbered grids, the search is found to be more orderly and accurate. The two trajectory indicators, namely argument angle and minimum distance, are analysed separately for the optimised results of the adaptive learning particle swarm optimisation algorithm, demonstrating that they can meet the actual processing *** results of NC EDM indicate that the motion path generated by this design method can meet the machining requirements of 3D curved and twisted flow channels.

关键词： Blisk Electrical discharge machining(EDM) Electrode Objective functions Trajectory generation

Online hierarchical recognition method for target tactical intention in beyond-visual-range air combat

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Defence Technology（防务技术） 2022年第8期18卷 1349-1361页

作者： Zhen Yang Zhi-xiao Sun Hai-yin Piao Ji-chuan Huang De-yun Zhou Zhang Ren School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Northwestern Polytechnical University Xi'an710072China The First military representative office of the Air Force Equipment Department in Chengdu Chengdu610091China

Online accurate recognition of target tactical intention in beyond-visual-range (BVR) air combat is an important basis for deep situational awareness and autonomous air combat decision-making, which can create pre-emptive tactical opportunities for the fighter to gain air superiority. The existing methods to solve this problem have some defects such as dependence on empirical knowledge, difficulty in interpreting the recognition results, and inability to meet the requirements of actual air combat. So an online hierarchical recognition method for target tactical intention in BVR air combat based on cascaded support vector machine (CSVM) is proposed in this study. Through the mechanism analysis of BVR air combat, the instantaneous and cumulative feature information of target trajectory and relative situation information are introduced successively using online automatic decomposition of target trajectory and hierarchical progression. Then the hierarchical recognition model from target maneuver element, tactical maneuver to tactical intention is constructed. The CSVM algorithm is designed for solving this model, and the computational complexity is decomposed by the cascaded structure to overcome the problems of convergence and timeliness when the dimensions and number of training samples are large. Meanwhile, the recognition result of each layer can be used to support the composition analysis and interpretation of target tactical intention. The simulation results show that the proposed method can effectively realize multi-dimensional online accurate recognition of target tactical intention in BVR air combat.

关键词： Beyond-visual-range(BVR)air combat Tactical intention recognition Hierarchical recognition model Cascaded support vector machine(CSVM) Trajectory decomposition Maneuver element

Crushing Mechanism of Spherical Tungsten Alloy Fragments Penetrate Thick Steel Plate Target

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Journal of Wuhan University of Technology(Materials Science) 2023年第2期38卷 445-450页

作者： WAN Mingming BAI Rong SHANG Zaifei WANG Yanli LIANG Jiayi LI xue Inner Mongolian Metal Materials Research Institute Yantai264003China National Defense Technology Key Laboratory of Impact Environmental Materials Yantai264003China military representative office in Yantai Region of Army Equipment Department Yantai264003China

Against protection requirements for high-speed fragments on the ground weapons,we carried out the research work of crushing mechanism at different impact speeds ofφ8.7 mm spherical tungsten alloy,the penetration to 603 armor steel was completed by 20 mm ballistic gun,and the ANSYS/LS-DYNA software was used to complete the numerical calculation of the *** find that there are different crushing mechanisms of spherical tungsten alloy with different speeds and low speed,the crushing mechanism of fragment is mainly controlled by overall plastic deformation,shearing stripping,and squeezing at a high pressure and a high *** crushing mechanism will have a spallation phenomenon in addition to the crushing mechanism under high pressure.

关键词： spherical tungsten alloy experimental research numerical simulation crushing mechanism high pressure affected zone spallation zone

Formation control for networked multiagent systems with a minimum energy constraint

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Chinese Journal of Aeronautics 2023年第1期36卷 342-355页

作者： Junlong LI Jianxiang xI Ming HE Bing LI Department of Physics Lüliang UniversityLüliang 033001China School of Missile Engineering Rocket Force University of EngineeringXi’an 710025China First military representative office of the Rocket Army Equipment Department in xi’an Xi’an 710025China

Minimum-energy formation achievement problems for networked multiagent systems are investigated,where information networks with leaderless and leader-follower structures are respectively addressed and information networks are randomly *** critical feature of this work is that the energy constraint is minimum in the sense of the linear matrix inequality,but limited-budget control and guaranteed-cost control cannot realize a minimum-energy ***,the leaderless minimum-energy formation control problem is converted into an asymp-totic stability one via a nonsingular transformation and state space decomposition,and based on linear matrix inequality techniques,sufficient conditions for analysis and design of leaderless minimum-energy formation achievement are proposed,respectively,which can be solved by the generalized eigenvalue ***,main results of minimum-energy formation achievement of leaderless networked multiagent systems are extended leader-follower networked multiagent systems,where the asymmetric property of the leader-follower information network is well dealt with by two nonsingular ***,two simulation examples are shown to verify the main results for minimum-energy formation achievements of leaderless and leader-follower networked multiagent systems,respectively.

关键词： Energy constraint Formation Minimum energy consump-tion Networked control systems Switching networks

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