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Multi-constrained intelligent gliding guidance via optimal control and DQN

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Science China(Information Sciences) 2023年第3期66卷 214-229页

作者： jianwen zhu Hao ZHANG Sibo ZHAO Weimin BAO School of Aerospace Science and Technology Xidian University China Aerospace Science and Technology Corporation

In order to improve the adaptability and robustness of gliding guidance under complex environments and multiple constraints, this study proposes an intelligent gliding guidance strategy based on the optimal guidance, predictor-corrector technique, and deep reinforcement learning(DRL). Longitudinal optimal guidance was introduced to satisfy the altitude and velocity inclination constraints, and lateral maneuvering was used to control the terminal velocity magnitude and position. The maneuvering amplitude was calculated by the analytical prediction of the terminal velocity, and the direction was learned and determined by the deep Q-learning network(DQN). In the direction decision model construction, the state and action spaces were designed based on the flight status and maneuvering direction, and a reward function was proposed using the terminal predicted state and terminal constraints. For DQN training, initial data samples were generated based on the heading-error corridor, and the experience replay pool was managed according to the terminal guidance error. The simulation results show that the intelligent gliding guidance strategy can satisfy various terminal constraints with high precision and ensure adaptability and robustness under large deviations.

关键词： gliding flight optimal guidance velocity control deep reinforcement learning intelligent decision

Face animation based on multiple sources and perspective alignment

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虚拟现实与智能硬件（中英文） 2024年第3期6卷 252-266页

作者： Yuanzong MEI Wenyi WANG Xi LIU Wei YONG Weijie WU Yifan zhu Shuai WANG jianwen CHEN School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324000China

Background Face image animation generates a synthetic human face video that harmoniously integrates the identity derived from the source image and facial motion obtained from the driving video.This technology could be beneficial in multiple medical fields,such as diagnosis and privacy protection.Previous studies on face animation often relied on a single source image to generate an output video.With a significant pose difference between the source image and the driving frame,the quality of the generated video is likely to be suboptimal because the source image may not provide sufficient features for the warped feature map.Methods In this study,we propose a novel face-animation scheme based on multiple sources and perspective alignment to address these issues.We first introduce a multiple-source sampling and selection module to screen the optimal source image set from the provided driving video.We then propose an inter-frame interpolation and alignment module to further eliminate the misalignment between the selected source image and the driving frame.Conclusions The proposed method exhibits superior performance in terms of objective metrics and visual quality in large-angle animation scenes compared to other state-of-the-art face animation methods.It indicates the effectiveness of the proposed method in addressing the distortion issues in large-angle animation.

关键词： Face animation Multiple-source driving Generative adversarial network Medical diagnostics

Energy storage optimization of ferroelectric ceramics during phase-transition process of amorphous/nanocrystalline and polycrystalline by using a phaseffeld model for dielectric breakdown

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Journal of Advanced Dielectrics 2024年第1期14卷 33-41页

作者： Suilong Huang jianwen Chen Zhen Su Xiucai Wang Wenbo zhu Wenjun Chen Xinmei Yu Peng Xiao School of Electronic and Information Engineering Foshan University Foshan 528000P.R.China School of Mechatronic Engineering and Automation Foshan University Foshan 528000P.R.China China-Australia Institute for Advanced Materials and Manufacturing Jiaxing University Jiaxing 314001P.R.China School of Materials Science and Hydrogen Energy Foshan University Foshan 528000P.R.China School of Physics and Optoelectronic Engineering Foshan University Foshan 528000P.R.China

Ferroelectric ceramics have the potential to be widely applied in the modern industry and military power systems due to their ultrafast charging/discharging speed and high energy density.Considering the structural design and electrical properties of ferroelectric capacitor,it is still a challenge to ffnd out the optimal energy storage of ferroelectric ceramics during the phase-transition process of amorphous/nanocrystalline and polycrystalline.In this work,a ffnite element model suitable for the multiphase ceramic system is constructed based on the phase ffeld breakdown theory.The nonlinear coupling relationship of multiple physical ffelds between multiphase ceramics was taken into account in this model.The basic structures of multiphase ceramics are generated by using the Voronoi diagram construction method.The speciffed structure of multiphase ceramics in the phase-transition process of amorphous/nanocrystalline and polycrystalline was further obtained through the grain boundary diffusion equation.The simulation results show that the multiphase ceramics have an optimal energy storage in the process of amorphous polycrystalline transformation,and the energy storage density reaches the maximum when the crystallinity is 13.96%and the volume fraction of grain is 2.08%.It provides a research plan and idea for revealing the correlation between microstructure and breakdown characteristics of multiphase ceramics.This simulation model realizes the nonlinear coupling of the multiphase ceramic mesoscopic structure and the phase ffeld breakdown.It provides a reference scheme for the structural design and performance optimization of ferroelectric ceramics.

关键词： Ferroelectric ceramics phase transition phase-field model dielectric breakdown energy storage

Metal-organic framework-based single-atom electro-/ photocatalysts: Synthesis, energy applications, and opportunities

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Carbon Energy 2024年第1期6卷 1-43页

作者： Munir Ahmad Jiahui Chen jianwen Liu Yan Zhang Zhongxin Song Shahzad Afzal Waseem Raza Liaqat Zeb Andleeb Mehmood Arshad Hussain Jiujun Zhang Xian-zhu Fu Jing-Li Luo Shenzhen Key Laboratory of Energy Electrocatalytic Materials Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhenGuangdongChina College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhenGuangdongChina College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhenGuangdongChina Department of Environmental Engineering China Jiliang UniversityHangzhouZhejiangChina Institute for Advanced Study Shenzhen UniversityShenzhenGuangdongChina School of Bioengineering Dalian University of TechnologyDalianLiaoningChina College of Materials Science and Engineering Fuzhou UniversityFuzhouFujianChina Institute for Sustainable Energy Shanghai UniversityShanghaiChina

Single-atom catalysts(SACs)have gained substantial attention because of their exceptional catalytic properties.However,the high surface energy limits their synthesis,thus creating significant challenges for further development.In the last few years,metal–organic frameworks(MOFs)have received significant consideration as ideal candidates for synthesizing SACs due to their tailorable chemistry,tunable morphologies,high porosity,and chemical/thermal stability.From this perspective,this review thoroughly summarizes the previously reported methods and possible future approaches for constructing MOF-based(MOF-derived-supported and MOF-supported)SACs.Then,MOF-based SAC's identification techniques are briefly assessed to understand their coordination environments,local electronic structures,spatial distributions,and catalytic/electrochemical reaction mechanisms.This review systematically highlights several photocatalytic and electrocatalytic applications of MOF-based SACs for energy conversion and storage,including hydrogen evolution reactions,oxygen evolution reactions,O_(2)/CO_(2)/N_(2) reduction reactions,fuel cells,and rechargeable batteries.Some light is also shed on the future development of this highly exciting field by highlighting the advantages and limitations of MOF-based SACs.

关键词： carbon energy generation MOF-derived-supported MOF-supported single atoms

Clinical guidelines for indications,techniques,and complications of autogenous bone grafting

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Chinese Medical Journal 2024年第1期137卷 5-7页

作者： Jianzheng Zhang Shaoguang Li Hongying He Li Han Simeng Zhang Lin Yang Wenxing Han Xiaowei Wang Jie Gao jianwen Zhao Weidong Shi zhuo Wu Hao Wang Zhicheng Zhang Licheng Zhang Wei Chen Qingtang zhu Tiansheng Sun Peifu Tang Yingze Zhang Senior Department of Orthopedics PLA General HospitalBeijing 100048China The National Clinical Research Center for Orthopedics Sports Medicine&RehabilitationBeijing 100048China The Trauma Orthopedic Branch of Chinese Orthopedic Association ShijiazhuangHebei 050051China Department of Orthopedic Surgery The Third Hospital of Hebei Medical UniversityShijiazhuangHebei 050051China Department of Microsurgical Trauma The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China

Autogenous bone grafts have long been considered the“gold standard”and most effective material in bone regeneration procedures.[1]Autogenous bone grafts are used to repair bone defects caused by nonunion,infection,tumor resection,and spinal and joint fusion.[2]It has been reported that more than 200,000 autologous bone grafts are performed in the United States each year.[3]Although there are no specific statistics on the annual number of bone grafts performed in China,autologous bone grafting is the most common surgical technique in orthopedics.The iliac crest remains the most common donor site,along with the fibula,ribs,tibial metaphysis,proximal humerus,distal radius,and greater trochanter.[4,5]Various bone-graft options provide different amounts and qualities of cortical,cancellous,and corticocancellous bone.[6,7]Autogenous bone graft is osteogenic,histocompatible,provides structural support.

关键词： grafting graft union

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中频真空电弧边缘击穿现象及仿真研究

电工技术学报 2024年第9期39卷 2887-2895页

作者：蒋原马速良武建文李擎朱立颖工业过程知识自动化教育部重点实验室(北京科技大学自动化学院) 北京100083 北方工业大学储能技术工程研究中心北京100144 北京航空航天大学自动化科学与电气工程学院北京100083 北京空间飞行器总体设计部北京100194

为深入掌握航空变频(360~800 Hz)电力系统中真空电器电弧特性,该文围绕中频灭弧室弧后发生的边缘击穿现象,以双温磁流体动力学仿真结合实验的研究方法,得到了以下结论:中频真空电弧离子数密度的最大值为2.6×10^(19)m^(-3),离子温度的... 详细信息

为深入掌握航空变频(360~800 Hz)电力系统中真空电器电弧特性,该文围绕中频灭弧室弧后发生的边缘击穿现象,以双温磁流体动力学仿真结合实验的研究方法,得到了以下结论:中频真空电弧离子数密度的最大值为2.6×10^(19)m^(-3),离子温度的范围为0.30~0.91eV,电子温度的范围为1.50~2.43 eV;电子与离子之间存在能量交换,电子温度的变化会引起离子温度的变化;最高离子温度出现在阳极触头边缘处,与实验发现的边缘击穿位置重合,证明了此处确实存在能量集中;中频真空电弧是超声速流体,速度在边界处减慢,根据动能热能互换原理,中频真空电弧的质量流运动规律是边缘击穿的本质原因。

关键词：航空变频电源中频真空电弧弧后击穿边缘击穿双温磁流体动力学模型

未确知条件下多枚导弹打击不规则面目标的毁伤效果评估

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国防科技大学学报 2024年第3期46卷 213-221页

作者：王志辉胡剑文朱晓敏张亚军军事科学院战略评估咨询中心北京100091 陆军炮兵防空兵学院南京校区江苏南京211132 国防科技大学系统工程学院湖南长沙410073

在信息缺乏的情况下,如何提高对多枚导弹打击不规则面目标毁伤效果评估的可信度是导弹作战运用研究的重难点。通过蒙特卡罗方法建立给定参数下的面目标毁伤效果评估模型;采用信度分布函数对该问题的未确知性进行评估,评估结果显示毁伤... 详细信息

在信息缺乏的情况下,如何提高对多枚导弹打击不规则面目标毁伤效果评估的可信度是导弹作战运用研究的重难点。通过蒙特卡罗方法建立给定参数下的面目标毁伤效果评估模型;采用信度分布函数对该问题的未确知性进行评估,评估结果显示毁伤效果未确知性较高;基于信度熵,分析导弹各个属性的未确知性对毁伤效果未确知性的影响;通过针对性减小影响大的属性的未确知性,迭代减小毁伤效果的未确知性。仿真实验结果表明面目标有效毁伤率的未确知范围得到显著减小。该研究能够有效指导毁伤效果评估工作,减小其中的不确定性。

关键词：毁伤评估面目标蒙特卡罗方法未确知性信度熵

芳烃联合装置C_(8)芳烃资源在炼化一体化加工优化设计

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石化技术 2024年第2期31卷 1-3页

作者：朱建文中海石油宁波大榭石化有限公司浙江宁波315000

通过对芳烃联合装置中C_(8)芳烃资源的全面分析以及节能方案的深入讨论,提出了一系列优化策略,以在提高装置经济性、降低运营成本和增强企业竞争力方面发挥积极作用,有助于进一步减少芳烃装置的能源消耗。

关键词：炼化一体化芳烃资源芳烃联合装置 C_(8)芳烃

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基于报警日志的炼化过程风险薄弱点深度挖掘

过程工程学报 2024年第3期24卷 371-380页

作者：朱英齐王倩琳张东胜窦站张建文北京化工大学机电工程学院北京100029 北京化工大学安全工程交叉学科研究中心北京100029

在复杂炼化生产过程中,工艺报警日志蕴含着丰富的潜在风险信息,有助于揭示危险性根源、预防过程安全事故发生。为此,本工作提出了一种基于报警日志的炼化过程风险薄弱点深度挖掘方法。首先,针对本工作类型的工艺报警日志,利用Word2Vec... 详细信息

在复杂炼化生产过程中,工艺报警日志蕴含着丰富的潜在风险信息,有助于揭示危险性根源、预防过程安全事故发生。为此,本工作提出了一种基于报警日志的炼化过程风险薄弱点深度挖掘方法。首先,针对本工作类型的工艺报警日志,利用Word2Vec词嵌入技术进行向量化预处理,同时通过Pearson相关系数法解析日志间的关联关系,以获取相关系数矩阵。其次,引入复杂网络(CN)理论,将相关系数矩阵转化为布尔矩阵,构建复杂炼化过程的风险表征网络模型。再次,采用逼近理想解排序法(TOPSIS)对所构建的网络模型开展节点重要度精确评估,主要涵盖度中心性、接近中心性和特征向量中心性3个指标。最后,根据网络节点重要度排序的优先级,可深度挖掘复杂炼化过程的风险薄弱点。以某套柴油加氢装置为例,分析结果表明,该方法可准确、有效地提取报警等级为“高高报(HH)”或“高报(HI)”的工艺报警日志,且与复杂炼化过程的实际运行工况相符。

关键词：风险薄弱点报警日志节点重要度复杂网络(CN) 逼近理想解排序法(TOPSIS)