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Topological Design of a Nanosatellite Structure with Optimal Frequency Responses Filled by Non-Uniform Lattices

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Chinese Journal of Mechanical Engineering 2024年第6期37卷 258-269页

作者： Cunyi Wang Bin Zhang songhua huang Weiyuan Dou Shengzhen Xin Jiayong Yan Beijing Satellite Manufacturer Co. Ltd.Beijing 100094China Beijing Jiaotong University Beijing 100044China Xi’an Jiaotong-Liverpool University Suzhou 215123China

Traditional structural forms are difficult to meet the lightweight requirements of subsequent spacecraft for load-bearing *** the aerospace industry,filling structure with lattices is a popular approach to reduce the weight of a ***,this design strategy has deficiencies in the spatial distribution of lattice cells as well as its affection on the mechanical *** this study,a two-step topology optimization technique is proposed to solve the spatial distribution problem of ***,an entire nanosatellite box composed of panels which filled with uniform lattices is sent to the vibration test to obtain the frequency ***,a finite element(FE)model of the nanosatellite structure which contains the same uniform lattices is built and validated with the obtained frequency data *** the subsequent calculation of topology *** equivalent model of the verified FE model is established by replacing the lattice cells in the sandwich layer with equivalent fictional ***,a topology optimization problem under the mass constraints is formulated for maximize the nature frequency,and a new light weighted nanosatellite which filled with non-uniform lattices is established by applying the density mapping method and the previous topology configuration *** separating the design problem of nanosatellite into two steps,the proposed optimization design method achieves the maximum frequency design under the weight ***,the frequency is also guaranteed to be around the nature *** results reveal that the mass of the new structure with non-uniform lattices is reduced by 50.32%and the frequency is increased by 1.19%.An important technical importance and application value of this proposed technique is that it improves the performance and design efficiency of the load-bearing structures of a nanosatellite,and this method has significant technical significance and application value.

关键词： Lattice structure design Topology optimization Nanosatellite Modal analysis

An effects analysis method for C4ISR system structure based on information flow 36

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An effects analysis method for C4ISR system structure based ...

第36届中国控制会议

作者： Zhang Jinfeng Zhu Chen huang songhua Yi Kan Wang Heng Information Systems Engineering Laboratory

ISBN: (纸本)9781538629185

Aiming at the impact of cyber attack threat on the performance of C4 ISR system,a structural effect modeling and simulation method of C4 ISR system based on information flow model is ***,the connotation of C4 ISR system structure effect is expounded,and two kinds of attack modes and three kinds of attack strategies are put *** structure information flow model is *** on this,the mathematical model of the damage degree for system structure based on the information flow and mathematical model of fallback effect for system structure based on the information flow delay are ***,the method of C4 ISR system structure effect simulation is validated by taking the simulation experiment of a regional command and control system as an example.

关键词： attack strategy information flow model damage effects fallback effect

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支持负载均衡和路由优化的网络移动增强协议

东南大学学报（自然科学版） 2010年第1期40卷 35-40页

作者：黄松华丁峰黄皓中国电子科技集团公司第28研究所C~4ISR技术国防科技重点实验室南京210007 南京大学软件新技术国家重点实验室南京210093

分析网络移动现有方案在多穴负载均衡和嵌套路由优化方面存在的问题.基于最优路径选择算法和相应的路径评价标准,提出了支持综合负载均衡和路由优化的网络移动增强协议.该协议实现多移动网络前缀、多移动路由器、多家乡代理的负载均衡... 详细信息

分析网络移动现有方案在多穴负载均衡和嵌套路由优化方面存在的问题.基于最优路径选择算法和相应的路径评价标准,提出了支持综合负载均衡和路由优化的网络移动增强协议.该协议实现多移动网络前缀、多移动路由器、多家乡代理的负载均衡以及嵌套多穴移动网络全局和内部路由优化,解决嵌套移动网络的多角路由、隧道嵌套问题.此外,该协议兼容以前的网络移动标准,改动较少.协议的性能分析结果表明,和已有的方案相比,增强协议在帮助移动网络获得高吞吐量的同时,传输延时降低了近一半,可用连接增加了30%,而且性能更加稳定.

关键词：网络移动负载均衡路由优化多穴嵌套

Research on Knowledge Viewpoint of Architecture for Command Information System

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Research on Knowledge Viewpoint of Architecture for Command ...

基于SIMP-安定的高速列车组合式座椅底架轻量化设计与分析

第37届中国控制会议

作者： ZHANG Zhaochen huang songhua ZHANG Jinfeng The 28th Research Institute of CETC Science and Technology on Information Systems Engineering Laboratory

The efficient use of knowledge is the driving force for future command information system to produce operational effectiveness of anticipating the enemy. The construction of intelligent command information system needs the specification of knowledge oriented architecture viewpoint models and the guidance of architecture design method. The mechanism of knowledge activity is discussed. The knowledge viewpoint models centered on knowledge activity of the command information system architecture are proposed. The design process of knowledge viewpoint based on capability is expounded. The example of operational application shows that the knowledge viewpoint can effectively guide the generation and application of knowledge in the command information system, and transform the information advantage into decision advantage and action advantage.

关键词： command information system architecture knowledge viewpoint knowledge activity

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工程科学学报 2024年第6期46卷 1151-1160页

作者：黄昌雄陈耕黄松华张乐乐北京交通大学机械与电子控制工程学院北京100044 北京交通大学轨道车辆运用工程国家国际科技合作基地北京100044 西交利物浦大学智能工程学院苏州215123

在高速列车座椅轻量化设计中,传统设计方法所普遍采用的结构优化技术仅以结构刚度或局部应力水平为目标,无法得到交变载荷作用下效率最高的结构构型.列车座椅在实际使用中受到轨道与应用场景的影响,除主结构需具备一定强度外,其关键部... 详细信息

在高速列车座椅轻量化设计中,传统设计方法所普遍采用的结构优化技术仅以结构刚度或局部应力水平为目标,无法得到交变载荷作用下效率最高的结构构型.列车座椅在实际使用中受到轨道与应用场景的影响,除主结构需具备一定强度外,其关键部件也要求在交变载荷作用下不发生明显变形.在此背景下,提出了一种采用固体各向同性惩罚微结构插值(SIMP)算法对主结构进行以刚度为目标的拓扑优化,同时以安定直接法对关键部件进行以安定强度为目标的参数优化一体化的设计与分析方法.采用所提出的方法对高速列车组合式座椅底架进行了优化,取得了显著成果.优化后的座椅底架在性能满足要求的前提下,底架主结构减重17%、L型连接件承载交变载荷的结构效率提高23%.所提出的研究方法及结果对于同类结构的轻量化设计具有重要意义.

关键词：高速列车底架拓扑优化安定轻量化

Study of spatiotemporal variation and annual emission of CH_(4)in Shaoxing Yangtze River Delta,China,Using a portable CH4 detector on the UAV

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Journal of Environmental Sciences 2025年第5期151卷 140-149页

作者： Xiaobing Pang Qianqian Shang Lang Chen songhua Sun Gaosheng Zhao Zhentao Wu Canming Zhao Youhao Lu Qianqian Sun Yan Lyu Baozhen Wang College of Environment Zhejiang University of TechnologyHangzhou 310000China Shaoxing Institute of Zhejiang University of Technology Shaoxing 312000China Shaoxing Ecological and Environmental Monitoring Center of Zhejiang Province Shaoxing 312000China School of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China Green Intelligence Environmental School Yangtze Normal UniversityChongqing 408100China

Methane(CH_(4))is the second greenhouse gas and has a profound impact on global climate change due to its high global warming potential and *** 2022,the CH_(4)concentration was approximately 1.9 ppm,which was 264%of the pre-industrial *** spatiotemporal distribution of CH_(4)was investigated by a portable CH_(4)detector on an unmanned aerial vehicle and electric bicycles in Shaoxing,a city situated in the Yangtze River Delta,*** vertical distribution revealed CH_(4)concentration generally decreased slowly with ***,the inversion condition and low atmospheric boundary layer height(ABLH)leaded to the enhancement of CH_(4)with *** highest CH_(4)concentration(2.2±0.1 ppm,n=1428)was observed in winter and the lowest(2.0±0.2 ppm,n=1530)in *** the daily variation,CH_(4)concentration peaked at 5:00 local time(LT)and reached its lowest level at 14:00 LT,which was attributed to the daily variation of ABLH,lowest in the early morning and highest in the *** urban areas,CH_(4)concentrations showed higher levels near restaurants,natural gas stations and sewerage well,with a maximum value of 13.1 ppm,which was caused by CH_(4)emission and natural gas leakage from these *** annual CH_(4)emission in Shaoxing were estimated to be approximately 69 ton/(km^(2)·year)by the mass balance *** with other cities in the world,the CH_(4)emission is in higher level which imply some control measures should be conducted to reduce CH_(4)emission in Shaoxing.

关键词： Portable CH_(4)detector Spatiotemporal variation Annual CH_(4)emission Unmanned aerial vehicle

Topological Design of a Nanosatellite Structure with Optimal Frequency Responses Filled by Non-Uniform Lattices

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Chinese Journal of Mechanical Engineering 2024年第6期 283-294页

作者： Cunyi Wang Bin Zhang songhua huang Weiyuan Dou Shengzhen Xin Jiayong Yan Beijing Satellite Manufacturer Co. Ltd. Xi'an Jiaotong-Liverpool University Beijing Jiaotong University

Traditional structural forms are difficult to meet the lightweight requirements of subsequent spacecraft for load-bearing structures. In the aerospace industry, filling structure with lattices is a popular approach to reduce the weight of a spacecraft. However, this design strategy has deficiencies in the spatial distribution of lattice cells as well as its affection on the mechanical properties. In this study, a two-step topology optimization technique is proposed to solve the spatial distribution problem of nanosatellite. Firstly, an entire nanosatellite box composed of panels which filled with uniform lattices is sent to the vibration test to obtain the frequency data. Then, a finite element(FE)model of the nanosatellite structure which contains the same uniform lattices is built and validated with the obtained frequency data above. For the subsequent calculation of topology optimization. An equivalent model of the verified FE model is established by replacing the lattice cells in the sandwich layer with equivalent fictional ***, a topology optimization problem under the mass constraints is formulated for maximize the nature frequency, and a new light weighted nanosatellite which filled with non-uniform lattices is established by applying the density mapping method and the previous topology configuration result. By separating the design problem of nanosatellite into two steps, the proposed optimization design method achieves the maximum frequency design under the weight constraint. Furthermore, the frequency is also guaranteed to be around the nature frequency. The results reveal that the mass of the new structure with non-uniform lattices is reduced by 50.32% and the frequency is increased by 1.19%. An important technical importance and application value of this proposed technique is that it improves the performance and design efficiency of the load-bearing structures of a nanosatellite, and this method has significant technical significance an

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建筑工程质量控制措施探析

江西建材 2020年第11期 120-120,122页

作者：黄松华东华理工大学江西南昌344000

文中分析了建筑工程施工过程中的质量问题,并提出了相应对策。

关键词：建筑工程工程质量质量控制

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固结不排水剪总应力强度指标的几点讨论

岩土力学 1999年第4期20卷 36-41页

作者：罗嗣海黄松华胡火旺华东地质学院资源与环境工程系临川344000 华东地质学院工程勘察研究院临川344000

建立了偏离室内常规三轴压缩试验应力条件下的总应力强度指标和有效固结压力强度指标的理论公式;讨论了这两种强度指标的变化规律及其与室内常规CU试验指标的差异;简要地分析了直接将室内常规CU试验指标用于压缩与伸长土单元的强度计算... 详细信息

建立了偏离室内常规三轴压缩试验应力条件下的总应力强度指标和有效固结压力强度指标的理论公式;讨论了这两种强度指标的变化规律及其与室内常规CU试验指标的差异;简要地分析了直接将室内常规CU试验指标用于压缩与伸长土单元的强度计算、用于有效固结压力法确定抗剪强度和用于土压力与地基极限承载力计算时的偏差情况。

关键词：总应力强度指标极限承载力固结不排水地基