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Self-consistent Clustering Analysis-Based Moving Morphable Component(SMMC)Method for Multiscale Topology Optimization

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Acta Mechanica Solida Sinica 2023年第6期36卷 884-898页

作者： yangfan li Jiachen Guo Hengyang li Huihan Chen Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA Theoretical and Applied Mechanics Program Northwestern UniversityEvanstonIL 60208USA Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China

Current multiscale topology optimization restricts the solution space by enforcing the use of a few repetitive microstructures that are predetermined,and thus lack the ability for structural concerns like buckling strength,robustness,and ***,in this paper,a new multiscale concurrent topology optimization design,referred to as the self-consistent analysis-based moving morphable component(SMMC)method,is *** with the conventional moving morphable component method,the proposed method seeks to optimize both material and structure simultaneously by explicitly designing both macrostructure and representative volume element(RVE)-level *** examples with transducer design requirements are provided to demonstrate the superiority of the SMMC method in comparison to traditional *** proposed method has broad impact in areas of integrated industrial manufacturing design:to solve for the optimized macro and microstructures under the objective function and constraints,to calculate the structural response efficiently using a reduced-order model:self-consistent analysis,and to link the SMMC method to manufacturing(industrial manufacturing or additive manufacturing)based on the design requirements and application areas.

关键词： Topology optimization Moving morphable component method Multiscale concurrent design Reduced-order model

Capacity-Based Channel Assignment Scheme in Multi-radio Multi-channel Wireless Mesh Networks

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Chinese Journal of Electronics 2015年第2期24卷 419-425页

作者： li yangfan WU Peng liU Xinhua School of Automation Huazhong University of Science and Technology School of Information Engineering Wuhan University of Technology Key Lab. of Broadband Wireless Communications and Sensor Networks Wuhan University of Technology

The capacity of wireless mesh networks can be greatly enhanced by equipping each mesh router with multiple radios and by exploiting multiple channels to reduce network interference. It has been proved that an efficient channel assignment scheme is critical to achieve the optimal network throughput. This paper presents a centralized channel assignment scheme for multi-radio multichannel wireless mesh networks. The scheme includes a spanner-based topology control operation and a linkranking channel assignment algorithm. In the topology control procedure, several links that cause intense interference are removed from the network without damage to the basic network connectivity. The channel assignment procedure improves the network throughput via ranking links based on the principle of load balance. The simulation results demonstrate that the proposed scheme outperforms the compared centralized channel assignment approach in terms of network throughput. The experimental results also indicate that the effectiveness of the proposed scheme is even evident in the case of heavy input traffic load where the potential interference in the network is severe.

关键词： Wireless mesh networks Channel assignment Topology control Ranking link

Latest research progress of marine microbiological corrosion and biofouling, and new approaches of marine anti-corrosion and anti-fouling

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Bioactive Materials 2019年第1期4卷 189-195页

作者： yangfan li Chengyun Ning School of Materials Science and Engineering South China University of TechnologyChina

Marine resources and industry have become one of the most important pillars in economic development all over the ***,corrosion of materials is always the most serious problem to the infrastructure and equipment served in marine *** have found that microbiologically influenced corrosion(MIC)and marine bio-fouling are two main mechanisms of marine corrosions due to the complicated marine environment and marine *** article summarized the latest research progress about these two mechanisms and indicated that both MIC and marine bio-fouling are closely related to the biofilms on material surfaces formed by the marine microorganisms and their *** a result,to prevent the occurrence of MIC and bio-fouling,it is important to control the microorganisms in biofilms or prevent the adhesion and formation of *** traditional method of using chemical bactericide or antifoulant faces the problems of pollution and microorganism *** article introduced four research approaches about the new tendency of applying new materials and technologies to cooperate with traditional chemicals to achieve better and longer effects with lower environment pollution through synergistic ***,some future research tendencies were proposed for whole marine anti-corrosion and anti-fouling areas.

关键词： Microbiologically influenced corrosion Marine bio-fouling Biofilms Synergistic action Anti-Corrosion

Analyzing the spatial patterns and drivers of ecosystem services in rapidly urbanizing Taihu Lake Basin of China

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Frontiers of Earth Science 2015年第3期9卷 531-545页

作者： Junyong AI Xiang SUN Lan FENG yangfan li Xiaodong ZHU State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210046 China Marine Science Research Institute Nanjing University Nanjing 210()93~ China Key Laboratory of Coastal and Wetland Ecosystems (Ministry of Education) College of theEnvironment & Ecology Xiamen University Xiamen 361102 China

Quantifying and mapping the distribution patterns of ecosystem services can help to ascertain which services should be protected and where investments should be directed to improve synergies and reduce trade- offs. Moreover, the indicators of urbanization that affect the provision of ecosystem services must be identified to determine which approach to adopt in formulating policies related to these services. This paper presents a case study that maps the distribution of mukiple ecosystem services and analyzes the ways in which they interact. The relationship between the supply of ecosystem services and the socio-economic development in the Taihu Lake Basin of eastern China is also revealed. Results show a significant negative relationship between crop production and tourism income （p 〈 0.005） and a positive relationship between crop production, nutrient retention, and carbon sequestration （p 〈 0.005）. The negative effects of the urbanization process on providing and regulating services are also identified through a comparison of the ecosystem services in large and small cities. Regression analysis was used to compare and elucidate the relative significance of the selected urbanization factors to ecosystem services. The results indicate that urbanization level is the most substantial factor inversely correlated with crop production （R2 = 0.414） and nutrient retention services （R2 = 0.572）. Population density is the most important factor that negatively affects carbon sequestration （R2 = 0.447）. The findings of this study suggest the potential relevance of ecosystem service dynamics to urbanization management and decision making.

关键词： Taihu Lake Basin ecosystem service rapid urbanization spatial pattern drivers

Exploring coupling coordination between urbanization and ecosystem quality （1985-2010）： a case study from lianyungang City, China

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Frontiers of Earth Science 2016年第3期10卷 527-545页

作者： Junyong AI Lan FENG Xiaowei DONG Xiaodong ZHU yangfan li State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210046 China Key Laboratory of Coasial and Wetland Ecosystems (Ministry of Education) College of the Environment and Ecology Xiamen University Xiamen 361102 China The Key Laboratory of the Coastal Zone Exploitation and Protection Ministry of Land and Resource Nanjing 210008 China Jiangsu Province Center for Environmental Science and Engineering Nanjing 210036 China

Urbanization processes affect the ecosystem through alterations in ecological functions and landscape patterns. Currently, analysis of the total ecosystem services value （ESV） has targeted the overall benefits which human beings obtain from the regional ecosystem but does not generally include information regarding ecological struc- tures and patterns. Therefore, the results cannot reflect the comprehensive state of the local ecosystem. We propose a new, integrative ecosystem quality indicator based on the ESV and landscape metrics for evaluating the quality of the regional ecosystem. We adopted the method of a coupled degree of coordination for evaluating the interrelationship between urbanization and ecosystem quality in lianyun- gang City from 1985 to 2010. The coupling degree of coordination between urbanization and ecosystem quality showed an inverse U-shaped curve. At the primary stage of urbanization （1985-1995）, the degree of coupling of urbanization and the ecosystem was just barely balanced. From 1995 until 2000, the coupling system reached a balanced condition, in which the urbanization level increased. Since 2000, the urbanization process has accelerated. The coordination between urbanization and the ecosystem achieved the optimum condition in 2005. A turning point appeared at the same time, and the degree of coupling coordination began falling from the optimum. Subsequently, the coupled system once more entered a barely balanced state. Overall, the comprehensive level of ecosystem quality decreased since 1985 and degraded sharply after 2005, suggesting an overall degradation of the local ecosystem quality.

关键词： urbanization ecosystem services value landuse change landscape metrics ecosystem quality

Multi-Material Topology Optimization of Structures Using an Ordered Ersatz Material Model

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Computer Modeling in Engineering & Sciences 2021年第8期128卷 523-540页

作者： Baoshou liu Xiaolei Yan yangfan li Shiwei Zhou Xiaodong Huang Fujian Key Laboratory of Automotive Electronics and Electric Drive Fujian University of TechnologyFuzhou350118China Key Laboratory of Advanced Technology for Vehicle Body Design&Manufacture Hunan UniversityChangsha410082China Faculty of Science Engineering and TechnologySwinburne University of TechnologyMelbourneVIC 3122Australia Centre for Innovative Structures and Materials School of EngineeringRMIT UniversityMelbourneVIC 3001Australia

This paper proposes a new element-based multi-material topology optimization algorithm using a single variable for minimizing compliance subject to a mass constraint.A single variable based on the normalized elemental density is used to overcome the occurrence of meaningless design variables and save computational *** from the traditional material penalization scheme,the algorithm is established on the ordered ersatz material model,which linearly interpolates Young’s modulus for relaxed design *** achieve a multi-material design,the multiple floating projection constraints are adopted to gradually push elemental design variables to multiple discrete *** the convergent element-based solution,the multiple level-set functions are constructed to tentatively extract the smooth interface between two adjacent *** 2D and 3D numerical examples are presented to demonstrate the effectiveness of the proposed algorithm and the possible advantage of the multi-material designs over the traditional solid-void designs.

关键词： Multi-material topology optimization ordered ersatz material model mass constraint single variable

Time-varying group formation control for second-order multi-agent systems with switching directed topologies 36

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Time-varying group formation control for second-order multi-...

Restricting factors of the development of SEA in China

第36届中国控制会议

作者： yangfan li Xiwang Dong Qingdong li Zhang Ren School of Automation Science and Electrical Engineering Science and Technology on Aircraft Control LaboratoryBeihang University

ISBN: (纸本)9781538629185

Time-varying group formation control problems for second-order multi-agent systems with switching directed topologies are studied in this *** agents in the multi-agent system are divided into subgroups to form pre-defined time-varying sub-formations and the directed topology can be switching which means that group formation and switching topologies are considered ***,a time-varying group formation protocol with switching directed topologies is proposed using local relative state information of each agent and its *** an algorithm to design the protocol is *** on the piecewise Lyapunov function theory,sufficient conditions for second-order multi-agent systems to achieve time-varying group formation with switching directed topologies are derived together with the time-varying group formation feasibility constraints and the threshold for the dwell ***,a numerical simulation with two subgroups is provided to demonstrate the effectiveness of the obtained theoretical results.

关键词： Time-varying formation group formation second-order dynamics multi-agent system switching directed topology

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Ecological Economy 2006年第1期2卷 55-61页

作者： Wang Xianghua Zhu Xiaodong li yangfan Chen Shanshan National Laboratory of Pollution Control and Resources Reuse School of Environment Nanjing UniversityNanjing

＂Environmental Impact Assessment Law of P. R. China＂ was promulgated on Oct. 28^th, 2002 and has been put into effect on Sep 1^th, 2003. This paper puts forward some important factors which restrict the development of Strategic Environmental Assessment according to the preliminary practices of SEA in China. These restricting factors are：（1） potential resistance from some departments; （2） poor cooperation between different departments; （3） limited availability of information resources （4） lack of well-developed SEA methods; （5） difficulties in public participation. The primary thought to solve these problems were proposed at policy and technique level.

关键词： Strategic environmental assessment: Development Restricting factors China

Integrating Climate Change Factors into Environmental Planning Innovation of the National 12^(th) Five Year Development Plan towards Climate Change in China

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Chinese Journal of Population,Resources and Environment 2011年第4期9卷 42-48页

作者： Yang Xiao li yangfan Yin Rongyao Sun Xiang Zhu Xiaodong State Key Laboratory of Pollution Control and Resources Reuse School of Environment Nanjing University Nanjing Jiangsu 210093 China

Effects on sustainable development of climate change have been going further *** Five Year Development Plan in China should have specific policies on how to take climate change impacts into account through the environmental *** fields distribute in three levels of natural bearing capacity,production system and human settlements,and include seven aspects:ecosystems,water resources,disasters and risks,low-carbon economy,vulnerable departments,urbanization,and coastland.

关键词： climate change environmental planning innovation the 12th Five Year Development Plan