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Task assignment in ground-to-air confrontation based on multiagent deep reinforcement learning

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Defence Technology（防务技术） 2023年第1期19卷 210-219页

作者： Jia-yi Liu Gang wang qiang Fu Shao-hua Yue Si-yuan wang Air and Missile Defense College Air Force Engineering UniversityXi'an710051China Air Force Engineering University Changle East RoadXi'anShaanxi710051China

The scale of ground-to-air confrontation task assignments is large and needs to deal with many concurrent task assignments and random *** at the problems where existing task assignment methods are applied to ground-to-air confrontation,there is low efficiency in dealing with complex tasks,and there are interactive conflicts in multiagent *** study proposes a multiagent architecture based on a one-general agent with multiple narrow agents(OGMN)to reduce task assignment *** the slow speed of traditional dynamic task assignment algorithms,this paper proposes the proximal policy optimization for task assignment of general and narrow agents(PPOTAGNA)*** algorithm based on the idea of the optimal assignment strategy algorithm and combined with the training framework of deep reinforcement learning(DRL)adds a multihead attention mechanism and a stage reward mechanism to the bilateral band clipping PPO algorithm to solve the problem of low training ***,simulation experiments are carried out in the digital *** multiagent architecture based on OGMN combined with the PPO-TAGNA algorithm can obtain higher rewards faster and has a higher win *** analyzing agent behavior,the efficiency,superiority and rationality of resource utilization of this method are verified.

关键词： Ground-to-air confrontation Task assignment General and narrow agents Deep reinforcement learning Proximal policy optimization(PPO)

Functionally Graded Stainless Steel Fabricated by Direct Laser Deposition: Anisotropy of Mechanical Properties and Hardness

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Acta Metallurgica Sinica(English Letters) 2018年第1期31卷 19-26页

作者： qiang wang Song Zhang Chun-hua Zhang Chen-Liang Wu Ling Ren Jian-qiang wang Jiang Chen School of Stomatology China Medical University School of Materials Science and Engineering Shenyang University of Technology Shenyang Dalu Laser Group Co. Ltd. Institute of Metal Research Chinese Academy of Sciences

Direct laser metal deposition is a kind of advanced rapid manufacturing technology, which can produce near net shape parts by depositing metal powders layer by layer. This study demonstrates fabrication, the anisotropy of mechanical properties and hardness of a graded steel. The characteristics of constituent phases, microstructure, mechanical anisotropy, and microhardness were investigated using electron backscatter diffraction, optical microscopy, tensile test machine, and microhardness tester. It was found that the graded steel is dense and free of cracks. The crystal structures of the as-built samples evolved in three grades from fcc structures to fcc ＋ bcc structures and then to bcc ＋ fcc structures. Samples in x and z directions showed obvious mechanical anisotropy. The samples machined in x direction showed higher strength and lower elongation than those machined in z direction due to the presence of lack-of-fusion pores and the higher metallurgical bonding between layers in the x direction. The microhardness of the as-built samples increased along the cross section from the substrate （159.7 HV） to the top surface （545.4 HV）.

关键词： Graded steel Direct laser metal deposition Electron backscatter diffraction (EBSD) Anisotropy of mechanical orooerties

Efficient distributed algorithms for holistic aggregation functions on random regular graphs

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Science China(Information Sciences) 2022年第5期65卷 32-50页

作者： Lin JIA qiang-Sheng hua Haoqiang FAN Qiuping wang Hai JIN National Engineering Research Center for Big Data Technology and System/Services Computing Technology and System Lab/Cluster and Grid Computing Lab School of Computer Science and TechnologyHuazhong University of Science and Technology Institute for Interdisciplinary Information Science Tsinghua University

In this paper, we propose efficient distributed algorithms for three holistic aggregation functions on random regular graphs that are good candidates for network topology in next-generation data *** three holistic aggregation functions include SELECTION（select the k-th largest or smallest element）,DISTINCT（query the count of distinct elements）, MODE（query the most frequent element）. We design three basic techniques — Pre-order Network Partition, Pairwise-independent Random Walk, and Random Permutation Delivery, and devise the algorithms based on the techniques. The round complexity of the distributed SELECTION is Θ（log N） which meets the lower bound where N is the number of nodes and each node holds a numeric element. The round complexity of the distributed DISTINCT and MODE algorithms are O（log;N/log log N） and O（log;N log log N） respectively. All of our results break the lower bounds obtained on general graphs and our distributed algorithms are all based on the CON GE S T model, which restricts each node to send only O（log N） bits on each edge in one round under synchronous communications.

关键词： distributed algorithms holistic aggregation function random regular graph \({\cal C}{\cal O}{\cal N}{\cal G}{\cal E}{\cal S}{\cal T}\) model communication complexity round complexity

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The Finite Temperature Effect on Josephson Junction between an s-Wave Superconductor and an s±-Wave Superconductor

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Chinese Physics Letters 2013年第7期30卷 213-216页

作者： wang Da LU Hong-Yan wang qiang-hua National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093 Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA School of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000

We investigate a Josephson junction between a one-band and a multi-band s-wave *** the multi-band lead is an s±-wave superconductor,we find that the critical Josephson current may change its sign when the temperature *** result confirms that this is a widespread effect of the s±-wave superconductor,independent of the type of the junction,the ratios of the gaps and superconducting transition temperatures,as long as the tunneling matrix elements have suitable *** novel effect comes directly from the opposite gap *** propose that the observation of this phenomena can be used to detect the s±-wave pairing symmetry in iron-based superconductors.

关键词： Josephson superconductor Superconductor

Lipomatous ependymoma with ZFTA:RELA fusion-positive:A case report

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World Journal of Clinical Cases 2025年第1期13卷 48-55页

作者： Xiao-Yu Zhao Juan-Han Yu Yi-hua wang Yi-Xin Liu Lu Xu Lin Fu Ning Yi China Medical University The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Department of Pathology The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Anshan Cancer Hospital Anshan 114000Liaoning ProvinceChina

BACKGROUND Ependymoma with lipomatous differentiation is a rare type of *** ZFTA fusion-positive supratentorial ependymoma is a novel tumor type in the 2021 World Health Organization classification of central nervous system *** fusion-positive lipomatous ependymoma has not been reported to *** SUMMARY We reported a case of a 15-year-old Chinese male who had a sudden convulsion lasting approximately six *** resonance imaging showed a round cystic shadow of approximately 1.9 cm×1.5 cm×1.9 cm under the right parieto-occipital *** examination showed characteristic perivascular pseudorosettes and adipose differentiation in the ***-chemical staining showed that the tumor cells were negative for cytokeratin,NeuN,Syn and p53,but positive for GFAP,vimentin and S-100 ***-ficant punctate intracytoplasmic EMA immunoreactivity was *** level of Ki-67 was about 5%.Genetic analysis revealed ZFTA:RELA fusion.A cranio-tomy with total excision of the tumor was *** follow-up time was 36 months,no evidence of disease recurrence was found in magnetic resonance *** Based on these findings,the patient was diagnosed as a ependymoma with ZFTA fusion and lipomatous *** case report provides information on the microscopic morphological features of ependymoma with ZFTA fusion and lipomatous differentiation,which can help pathologists to make a definitive diagnosis of this tumor.

关键词： Ependymoma Lipomatous Molecular classification Supratentorial ZFTA:RELA fusion Case report

Study on reduction of MoS_2 powders with activated carbon to produce Mo_2C under vacuum conditions

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 405-412页

作者： Guo-hua Zhang He-qiang Chang Lu wang Kuo-chih Chou State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

A method of preparing Mo2C via vacuum carbothermic reduction of MoS2 in the temperature range of 1350–1550°C was proposed. The effects of MoS2-to-C molar ratio（a, a = 1：1, 1：1.5, and 1：2.5） and reaction temperature（1350 to 1550°C） on the reaction were studied in detail. The phase transition, morphological evolution, and residual sulfur content of the products were analyzed by X-ray diffraction, field-emission scanning electron microscopy, and carbon–sulfur analysis, respectively. The results showed that the complete decomposition of MoS2 under vacuum is difficult, whereas activated carbon can react with MoS2 under vacuum to generate Mo2C. Meanwhile, higher temperatures and the addition of more carbon accelerated the rate of carbothermic reduction reaction and further decreased the residual sulfur content. From the experimental results, the optimum molar ratio α was concluded to be 1：1.5.

关键词： vacuum treatment carbon thermoreduction molybdenum minerals molybdenum carbide microstructure