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综合飞行/推进控制系统的特征值灵敏度分析和设计

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航空学报 1989年第6期10卷 B280-B287页

作者：申功璋陈宗基彭可茂北京航空航天大学

在综合飞行/推进控制系统中,子系统之间的相互作用对飞机的稳定性、控制和性能具有直接的影响。本文应用特征值灵敏度分析法研究耦合系数的大小对系统稳定性的影响;应用增益灵敏度分析,进行减状态反馈次优设计,仿真结果表明设计合理,方... 详细信息

在综合飞行/推进控制系统中,子系统之间的相互作用对飞机的稳定性、控制和性能具有直接的影响。本文应用特征值灵敏度分析法研究耦合系数的大小对系统稳定性的影响;应用增益灵敏度分析,进行减状态反馈次优设计,仿真结果表明设计合理,方法可行。

关键词：综合控制系统推进控制灵敏度

Magnet stage optimization of 5 kW multi-cusped field thruster

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Plasma Science and Technology 2020年第9期22卷 128-138页

作者： peng HU Daren YU Yan shen Beijing Institute of Control Engineering Beijing 100094People's Republic of China Lab of Advanced Space Propulsion Beijing 100094People’s Republic of China Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology Beijing 100094People’s Republic of China Plasma Propulsion Laboratory of Harbin Institute of Technology Harbin 150001People's Republic of China School of aeronautics and astronautics Sun Yat-sen UniversityGuangzhou 510006People's Republic of China

The multi-cusped field thruster is a unique electric thruster device,which has many advantages such as long lifetime,large-range thrust throttling ability,high thrust density,and low *** thruster employs several alternating polarity permanent magnets to create a periodic magnetic field with several *** studies have indicated that the basic ionization and acceleration processes are directly related to the electron motion behavior,which mainly depends on the magnetic field *** magnet number and magnet stage length are two key magnetic field parameters that have important effects on the thruster *** this paper,both the magnet number and magnet stage length parameters are studied for the optimization of a 5 k W multi-cusped field *** results indicate that the three-stage thruster has a better electron confinement than the two-stage *** has lower ion energy loss at the wall,and shows a higher ionization ***,the three-stage magnetic field is a superior magnetic field ***,the three-stage magnetic field simulation results indicate that an optimal accelerating electric field distribution and ionization region distribution could be obtained when the magnet length ratio is 78:25:20.

关键词： multi-cusped field magnet number magnet length performance optimization

A distributed consensus filter for sensor networks with heavy-tailed measurement noise

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Science China(Information Sciences) 2018年第11期61卷 244-246页

作者： peng DONG Zhongliang JING Kai shen Minzhe LI School of aeronautics and astronautics Shanghai Jiao Tong University

Dear editor,Distributed state estimation is very important in distributed sensor networks (DSNs)[1]. The consensus estimation can make the sensor networks achieve global consistency according to the data of all nodes [2]. It is very useful for the state estimation of DSNs. The fusion center and full connection between network nodes are not required. The

关键词： A distributed consensus filter for sensor networks with heavy-tailed measurement noise

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自动机动轰炸系统进入段轨迹生成研究

北京航空航天大学学报 1999年第3期25卷 351-354页

作者：彭可茂申功璋文传源北京航空航天大学自动控制系

目前综合飞行／火力控制主要研究从瞄准到武器投放的攻击过程，对进入段研究较少．采用手动控制为机翼非水平甩投轰炸方式创造攻击过渡点是非常困难的．进入段自动控制将会为其提供良好的攻击过渡点，并减轻飞行员操纵负担．它的核心问... 详细信息

目前综合飞行／火力控制主要研究从瞄准到武器投放的攻击过程，对进入段研究较少．采用手动控制为机翼非水平甩投轰炸方式创造攻击过渡点是非常困难的．进入段自动控制将会为其提供良好的攻击过渡点，并减轻飞行员操纵负担．它的核心问题是轨迹生成，因此，提出一种简化飞机质点运动模型和最短时间优化控制相结合的方法，生成进入段期望轨迹．该方法能够得到解析表达的期望轨迹参数，并能够满足轨迹生成的实时计算要求．数学仿真表明，所提出的轨迹生成方法为机翼非水平甩投轰炸方式创造了理想的攻击过渡点。

关键词：火力控制系统飞行控制进入段自动轰炸系统

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战斗机大幅值机动运动准稳态设计方法

北京航空航天大学学报 1999年第1期25卷 26-29页

作者：彭可茂申功璋文传源北京航空航天大学

根据战斗机大幅值机动运动特点，提出了准稳态运动概念及其设计方法．以准稳态运动为基准，对其运动非线性分析，并适当简化，生成准稳态运动的期望状态、输出、控制和小扰动线性化模型．采用ＬＱＲ设计方法整定ＰＩＤ调节器参数．由准... 详细信息

根据战斗机大幅值机动运动特点，提出了准稳态运动概念及其设计方法．以准稳态运动为基准，对其运动非线性分析，并适当简化，生成准稳态运动的期望状态、输出、控制和小扰动线性化模型．采用ＬＱＲ设计方法整定ＰＩＤ调节器参数．由准稳态运动的期望状态、输出、控制和调节器组成系统控制器．分别以四种准稳态运动为基准，设计了大幅值机动运动控制律．在六自由度全量飞机模型上的仿真结果表明，所提出的设计方法是可行的．

关键词：飞行控制航迹控制战斗机非线性准稳态

In-situ deposition of apatite layer to protect Mg-based composite fabricated via laser additive manufacturing

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Journal of Magnesium and Alloys 2023年第2期11卷 629-640页

作者： Youwen Yang Changfu Lu Lida shen Zhenyu Zhao Shuping peng Cijun Shuai Institute of Bioadditive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013China Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China shenzhen Institute of Information Technology Shenzhen 518172China NHC Key Laboratory of Carcinogenesis School of basic Medical ScienceCentral South UniversityChangshaHunan 410013China School of energy and machinery engineering Jiangxi University of Science and TechnologyNanchang 330013China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China

Biodegradable magnesium(Mg) and its alloy show huge potential as temporary bone substitute due to the favorable biocompatibility and mechanical compatibility. However, one issue deserves attention is the too fast degradation. In this work, mesoporous bioglass(MBG)with high pore volume(0.59 cc/g) and huge specific surface area(110.78 m^(2)/g) was synthesized using improved sol-gel method, and introduced into Mg-based composite via laser additive manufacturing. Immersion tests showed that the incorporated MBG served as powerful adsorption sites, which promoted the in-situ deposition of apatite by successively adsorbing Ca2+and HPO42-. Such dense apatite film acted as an efficient protection layer and enhanced the corrosion resistance of Mg matrix, which was proved by the electrochemical impedance spectroscopy measurements. Thereby, Mg based composite showed a significantly decreased degradation rate of 0.31 mm/year. Furthermore,MBG also improved the mechanical properties as well as cell behavior. This work highlighted the advantages of MBG in the fabrication of Mg-based implant with enhanced overall performance for orthopedic application.

关键词： Laser addictive manufacture Mg-based composite Mesoporous bioglass In-situ deposition Degradation behavior

A bifunctional bone scaffold combines osteogenesis and antibacterial activity via in situ grown hydroxyapatite and silver nanoparticles

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Bio-Design and Manufacturing 2021年第3期4卷 452-468页

作者： Youwen Yang Yun cheng Fang Deng Lida shen Zhenyu Zhao Shuping peng Cijun Shuai Institute of Bioadditive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013China Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China shenzhen Institute of Information Technology Shenzhen 518172China NHC Key Laboratory of Carcinogenesis School of Basic Medical ScienceCentral South UniversityChangsha 410013China School of Energy and Machinery Engineering Jiangxi University of Science and TechnologyNanchang 330013China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China

Hydroxyapatite(HA)nanoparticles and silver(Ag)nanoparticles are expected to enable desirable bioactivity and antibac-terial properties on biopolymer ***,interfacial adhesion between HA/Ag and the biopolymer is poor due to the large physicochemical differences between these *** this study,poly L-lactic acid(PLLA)powder was first surface-modified with bioactive polydopamine(PDA)in an alkaline ***,HA and Ag nanoparticles were grown in situ on the PDA-coated PLLA powder,which was then adhered to the porous bone scaffold using a selective laser-sintering *** showed that HA and Ag nanoparticles were homogenously distributed in the matrix,with enhanced mechanical *** body fluid bioactivity tests showed that the in situ grown HA-endowed scaffold shows excellent *** vitro tests confirmed that the scaffold exhibits favorable biocompatibility with human umbilical cord mesenchymal stem cells,as well as strong antibacterial activity against Gram-negative Escherichia ***,in vivo assays indicated that the scaffold promoted bone generation,with a new bone area fraction of 71.8%after 8 weeks’implantation,without inflammation.

关键词： Bone scaffold In situ growth Hydroxyapatite Antibacterial properties Surface modification

Microstructure development and biodegradation behavior of additively manufactured Mg-Zn-Gd alloy with LPSO structure

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Journal of Materials Science & Technology 2023年第13期144卷 1-14页

作者： Youwen Yang chenrong Ling Yageng Li Shuping peng Deqiao Xie Lida shen Zongjun Tian Cijun Shuai Institute of Additive Manufacturing Jiangxi University of Science and TechnologyNanchang 330013China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education Xiangya HospitalCentral South UniversityChangsha 410078China NHC Key Laboratory of Carcinogenesis of Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine Cancer Research InstituteSchool of Basic Medical ScienceCentral South UniversityChangsha 410013China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China

Biodegradable magnesium(Mg)alloy has been considered as a new generation of orthopedic implant ***,local corrosion usually occurs since the severe micro-galvanic behavior amongα-Mg and precipitates,and results in too rapid *** this study,porous Mg-Zn-Gd part was fabricated using laser additive manufacturing combined with solution heat *** heat treatment,the precipitatedβ-(Mg,Zn)_(3) Gd phase dissolved inα-Mg,and reduced the energy threshold of stacking faults on basal planes,which finally triggered the formation of long period stacking ordered(LPSO)*** LPSO phases owned minor potential difference withα-Mg,thus causing less micro-galvanic corrosion ten-dency as compared toβ-(Mg,Zn)_(3) Gd *** importantly,they were uniformly distributed within theα-Mg grains and showed different orientations between adjacent *** a result,the LPSO-reinforced Mg-Zn-Gd tended to expand laterally during corrosion evolution,and achieved uniform degradation with a considerably reduced degradation rate of 0.34 mm/***,in-vitro cell tests further proved its favorable *** work highlighted the additively manufactured Mg-Zn-Gd with LPSO structure showed great potential for orthopedic application.

关键词： Additive manufacturing Mg alloy LPSO structure Biodegradation behavior Biocompatibility

一种基于VxWorks的飞行仿真实时管理系统

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系统仿真学报 2003年第7期15卷 966-968页

作者：彭华沈为群宋子善北京航空航天大学自动化科学与电气工程学院北京100083

结合北京航空航天大学自动控制系开发的某大型工程飞行模拟器系统,介绍了一种基于嵌入式实时操作系统VxWorks和多处理机系统的仿真系统结构及其开发环境。首先介绍了VxWorks的特点。然后介绍了飞行仿真系统的总体结构及管理系统的主要... 详细信息

结合北京航空航天大学自动控制系开发的某大型工程飞行模拟器系统,介绍了一种基于嵌入式实时操作系统VxWorks和多处理机系统的仿真系统结构及其开发环境。首先介绍了VxWorks的特点。然后介绍了飞行仿真系统的总体结构及管理系统的主要功能。最后讨论了实时管理系统实现中的关键问题,包括多任务管理在不同开发环境下的实现以及分布式仿真系统的实时数据通讯等。

关键词： VxWorks 飞行仿真实时系统多任务通讯