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Reward Function Design Method for Long Episode Pursuit Tasks Under Polar Coordinate in Multi-Agent Reinforcement Learning

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Journal of Shanghai Jiaotong university(Science) 2024年第4期29卷 646-655页

作者： DONG Yubo CUI Tao ZHOU Yufan song xun ZHU Yue DONG Peng School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China Beijing Institute of Electronic System Engineering Beijing100854China

Multi-agent reinforcement learning has recently been applied to solve pursuit ***,it suffers from a large number of time steps per training episode,thus always struggling to converge effectively,resulting in low rewards and an inability for agents to learn *** paper proposes a deep reinforcement learning(DRL)training method that employs an ensemble segmented multi-reward function design approach to address the convergence problem mentioned *** ensemble reward function combines the advantages of two reward functions,which enhances the training effect of agents in long ***,we eliminate the non-monotonic behavior in reward function introduced by the trigonometric functions in the traditional 2D polar coordinates observation *** results demonstrate that this method outperforms the traditional single reward function mechanism in the pursuit scenario by enhancing agents’policy scores of the *** ideas offer a solution to the convergence challenges faced by DRL models in long episode pursuit problems,leading to an improved model training performance.

关键词： multi-agent reinforcement learning deep reinforcement learning(DRL) long episode reward function

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基于覆盖理论的高速强机动目标协同围捕策略

工程科学学报 2024年第7期46卷 1169-1178页

作者：江涌王林波王蒙一宋勋安鹏飞于江龙中国长峰机电研究院北京100854 北京电子工程总体研究所北京100854 北京遥感设备研究所北京100854 北京航空航天大学人工智能研究院北京100191

为了应对进攻性高超声速飞行器带来的威胁与挑战,基于覆盖理论提出了一种针对高速强机动目标的分布式协同围捕策略.首先,考虑飞行器与目标的机动特性,包括速度关系、最大过载比等参数,引入阿波罗尼奥斯圆的概念对围捕区域进行分析.然后... 详细信息

为了应对进攻性高超声速飞行器带来的威胁与挑战,基于覆盖理论提出了一种针对高速强机动目标的分布式协同围捕策略.首先,考虑飞行器与目标的机动特性,包括速度关系、最大过载比等参数,引入阿波罗尼奥斯圆的概念对围捕区域进行分析.然后,基于重叠角概念提出冗余覆盖策略,根据目标的逃逸边界给出初始飞行器最优数量,设计围捕队形使多飞行器的围捕区域能够对目标逃逸边界完全覆盖,在此基础上考虑多种约束设计围捕高速强机动目标的分布式协同制导律,使多飞行器能够完成所设计的围捕队形,达到目标被飞行器合围后无法逃脱的效果.最后,将上述覆盖策略分别在二维平面和三维空间进行数值仿真,验证了一致性协同制导律能够实现期望的围捕队形,所设计的围捕队形在目标作最大常值机动逃逸以及随机机动两种情况下均能捕获目标,证明了围捕队形和制导律的有效性和优越性.

关键词：覆盖理论协同围捕高速强机动目标阿波罗尼奥斯圆围捕区域

基于图像语义分割与结构保持约束的风机叶片拼接技术

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现代防御技术 2024年第4期52卷 123-129页

作者：许恒雷陈帅旗宋勋朱洺洁鲁能新能源(集团)有限公司北京100020 北京电子工程总体研究所北京100854

以无人机对风机叶片的巡检拍摄为应用背景,开展了风机叶片图像的拼接方法研究,提出了一种先进行背景分割然后进行图像网格化拼接的处理方法。通过深度学习U-Net算法,进行图像中风机主体部分的提取,该处理能够有效处理多视角大视差、目... 详细信息

以无人机对风机叶片的巡检拍摄为应用背景,开展了风机叶片图像的拼接方法研究,提出了一种先进行背景分割然后进行图像网格化拼接的处理方法。通过深度学习U-Net算法,进行图像中风机主体部分的提取,该处理能够有效处理多视角大视差、目标背景特征点分布不均导致的风机叶片拼接困难的问题;在图像网格优化的过程中,基于保护风叶全局线性度的策略设计能量函数,优化得到的网格顶点对风机边缘的直线特征进行了有效保护。实现了多幅风机叶片的自然拼接,拼接得到的图像视觉效果畸变小、连续真实。

关键词：图像语义分割 as-projective-as-possible(APAP) 网格化图像拼接直线结构保持深度学习特征提取

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Robust LPV missile autopilot design with parameter dependent performance 25th

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Robust LPV missile autopilot design with parameter dependent...

Clinical features,radiological imaging,and treatment strategies of nonmetallic intraorbital foreign bodies:a retrospective analysis

第25届中国控制与决策会议

作者： xun song Jianshuang song Zhang Ren Science and Technology on Aircraft Control Laboratory Beihang University

ISBN: (纸本)9781467355322

In this paper the application of linear parameter varying （LPV） control with parameter dependent performance to an advanced missile is presented. The existing LPV control techniques are based on robust control theory using a uniform upper performance bound over the whole parameter space. So the controller performance might be limited by the worst-case parameter variations. To deal with this problem, the constant performance bound is generalized as functions of the scheduling parameters for the general LPV systems. The controller synthesis conditions are reformulated as linear matrix inequalities （LMIs） which can be solved efficiently by the convex optimization algorithms. The missile autopilot design was used to illustrate this systematic approach.

关键词： LPV parameter dependent performance missile autopilot LMI

来源： cnki会议评论

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International Journal of Ophthalmology(English edition) 2023年第7期16卷 1130-1137页

作者： Guang-Rui Chai Ming Chen Zi-xun song Lu Liu Department of Ophthalmology Shengjing Hospital of China Medical UniversityShenyang 110004Liaoning ProvinceChina

AIM:To provide comprehensive data on nonmetallic intraorbital foreign bodies(IOFBs)by summarizing and analyzing material types,clinical manifestations,imaging features,and treatment ***:Totally 28 nonmetallic IOFB cases treated at Shengjing Hospital of China Medical University from 2012 to 2020 were retrospectively *** types of foreign bodies,clinical features,imaging manifestations,and treatment outcomes were ***:Among all cases,67.8%(19/28)of the foreign bodies were *** top three entrances were the upper eyelid skin(7/28),lower fornix conjunctiva(6/28),and lower eyelid skin(4/28).In most cases(11/28,39.3%),foreign bodies remained in the medial *** major clinical manifestations included eyelid redness and swelling(20/28,71.4%),conjunctival congestion and edema(17/28,60.7%),and ophthalmoptosis(15/28,53.6%).Infection was the main complication,which occurred in 57.1%(16/28)of all *** tomography(CT)values differed for different foreign bodies and varied in the different periods after *** plant-and grease-derived foreign bodies and the surrounding pus cysts showed different signals on magnetic resonance imaging(MRI).The prognosis varied with different foreign body types,surgery timing,and intraoperative ***:The majority of nonmetallic IOFBs are organic and often remain in the superior,medial,and inferior areas of the *** manifestations vary owing to their different *** and MRI facilitate the identification of foreign body ***-derived foreign bodies should be completely removed,and surgical treatment is a complicated process.

关键词： orbital trauma nonmetallic intraorbital foreign body clinical manifestations computed tomography magnetic resonance imaging

Equilibrium between titanium ions and high-purity titanium electrorefining in a NaCl-KCl melt

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International Journal of Minerals,Metallurgy and Materials 2014年第7期21卷 660-665页

作者： Jian-xun song Qiu-yu Wang Guo-jing Hu Xiao-bo Zhu Shu-qiang Jiao Hong-min Zhu State Key Lab of Advanced Metallurgy University of Science and Technology Beijing

TiClx （x=2.17） was prepared by using titanium sponge to reduce the concentration of TiCl4 in a NaCl-KCl melt under negative pressure. The as-prepared NaCl-KCl-TiClx melt was employed as the electrolyte, and two parallel crude titanium plates and one high-purity titanium plate were used as the anode and cathode, respectively. A series of electrochemical tests were performed to investigate the influence of electrolytic parameters on the current efficiency and quality of cathodic products. The results indicated that the quality of cathodic products was related to the current efficiency, which is significantly dependent on the current density and the initial concentration of titanium ions. The significance of this study is the attainment of high-purity titanium with a low oxygen content of 30× 10^-6.

关键词： titanium electrodeposition ionic equilibrium high purity materials oxygen concentration

On the Quantum Cohomology of Blow-ups of Four-dimensional Quadrics

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Acta Mathematica Sinica,English Series 2024年第1期40卷 313-328页

作者： Jian xun HU Hua Zhong KE Chang Zheng LI Lei song School of Mathematics Sun Yat-sen UniversityGuangzhou 510275P.R.China

We propose a conjecture relevant to Galkin’s lower bound conjecture,and verify it for the blow-ups of a four-dimensional quadric at a point or along a projective *** also show that Conjecture O holds in these two cases.

关键词： Quantum cohomology blow-up quadric hypersurface

Reaction mechanism between Al_(2)O_(3)–MgO refractory materials and rare earth high-carbon heavy rail steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1153-1163页

作者： Yi Wang Guang-jie song Ping Shen Jian-zhong He Da-xian Zhang Jian-xun Fu Center for Advanced Solidification Technology(CAST) School of Materials Science and EngineeringState Key Laboratory of Advanced Special SteelShanghai UniversityShanghai200444China State Key Laboratory of Baiyunebo Rare Earth Resources Research and Comprehensive Utilization Baotou014030Inner MongoliaChina Inner Mongolia Baotou Steel Union Co. Ltd.Baotou014030Inner MongoliaChina

Submerged entry nozzle(SEN)clogging is a major problem affecting the production quality of rare earth steel,and finding a suitable refractory outlet can significantly reduce production *** explore the relationship between refractory composition and interface interaction,unprotected coated Al_(2)O_(3)–MgO refractories and SiO2-coated Al_(2)O_(3)–MgO refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions,and the Al_(2)O_(3)–MgO refractory was found to be more *** results show that,from the epoxy resin side to the refractory side,the contour of the refractory interface reaction layer can be divided into two main layers:an iron-rich reaction layer and an iron-poor reaction *** based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions,and the same result applies to the surface *** the inclusions at a smaller size has a specific effect on alleviating the erosion of *** with the erosion mechanism of Al_(2)O_(3)–MgO refractories,the interface reaction mechanism between Al_(2)O_(3)–MgO refractories and molten steel was proposed,which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al_(2)O_(3)-MgO refractory Adhesion Surface tension Interface interaction

Mg-Al-hydrotalcite with alkaline sites protects Ni/KIT-6 from formation of amorphous coke in glycerol steam reforming via tailoring reaction intermediates

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 25-39页

作者： Yunyu Guo Yiran Wang Yuewen Shao Shu Zhang Yi Wang song Hu Jun Xiang xun Hu School of Material Science and Engineering University of JinanJinan 250022China Joint International Research Laboratory of Biomass Energy and Materials College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China

During steam reforming,the performance of a catalyst and amount/property of coke are closely related to reaction intermediates reaching surface of a ***,modification of reaction intermediates by placing Mg-Al-hydrotalcite above Ni/KIT-6 catalyst in steam reforming of glycerol was conducted at 300 to 600°*** results revealed that the catalytic activity of Ni/KIT-6 in the lower bed was enhanced with either Mg1-Al5-hydrotalcite(containing more acidic sites)or Mg5-Al1-hydrotalcite(containing more alkaline sites)as upper-layer *** in situ infrared characterization of steam reforming demonstrated that Mg-Al-hydrotalcite catalyzed the deoxygenation of glycerol,facilitating the reforming of the partially deoxygenated intermediates over Ni/***-Al-hydrotalcite as protective catalyst,however,did not protect the Ni/KIT-6 from formation of more ***,this did not lead to further deactivation of Ni/KIT-6 while Mg5-Al1-hydrotalcite even substantially enhanced the catalytic stability,even though the coke was much more significant than that in the use of single Ni/KIT-6(52.7%vs.28.6%).The reason beneath this was change of the property of coke from more aliphatic to more ***5-Al1-hydrotalcite catalyzed dehydration of glycerol,producing dominantly reaction intermediates bearing C=C,which formed the catalytic coke of with carbon nanotube as the main form with smooth outer walls as well as higher aromaticity,C/H ratio,crystallinity,crystal carbon size,thermal stability,and resistivity toward oxidation on Ni/KIT-6 in the lower *** comparison,the abundance of acidic sites on Mg1-Al5-hydrotalcite catalyzed the formation of more oxygen-containing species,leading to the formation of carbon nanotubes of rough surface on Ni/KIT-6.

关键词： steam reforming of glycerol Mg-Alhydrotalcite sacrificial catalyst reaction intermediates property of coke