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控制理论与应用（英文版） 2012年第2期10卷 216-222页

作者： zhiyuan liu 1 , guowei fan 1 , hong chen 2 1.department of control science and engineering, har.in institute of technology, har.in heilongjiang 150001, china 2.department of control science and engineering, Jilin University, Changchun Jilin 130025, china department of control science and engineering Harbin Institute of Technology Harbin Heilongjiang China department of control science and engineering Jilin University Changchun Jilin China

Stabilization problem of discrete-time linear switching systems with bounds on the state and control input is solved in this paper. First, the synthesis of state feedback controllers that ensure the stability of closed-loop switching systems is studied under a sufficient condition. By using the idea of positive invariance, a stabilizing controller design methodology is proposed. Based on these results, the convergence rate problem is also discussed. A state feedback controller that guarantees the optimal convergence rate of closed-loop switching systems is obtained via optimization. Finally, an example made up of two subsystems is studied to show the application of our method.

关键词： Switching systems Constraints Stabilization problem Convergence rate problem

Robust observer-based control for uncertain discrete-time piecewise affine systems

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控制理论与应用（英文版） 2012年第2期10卷 236-243页

作者： Yahui GAO 1 , zhiyuan liu 2 , hong chen 3 1.AVIC (Aviation Industry Corporation of china) china Aviation Motor control System institute, Wuxi Jiangsu 214063, china 2.department of control science and engineering, har.in institute of technology, har.in heilongjiang 150001, china 3.department of control science and engineering, Jilin University, Changchun Jilin 130025, china AVIC (Aviation Industry Corporation of china) china Aviation Motor control System institute Wuxi Jiangsu China department of control science and engineering Harbin Institute of Technology Harbin Heilongjiang China department of control science and engineering Jilin University Changchun Jilin China

The main contribution of this paper is to present a novel robust observer-based controller design method for discrete-time piecewise affine systems with norm-bounded uncertainties. The key ideas are to construct a piecewise quadratic Lyapunov function to guarantee the stability of the closed-loop systems, approximate polytopic operating regions by ellipsoids, and use the singular value decomposition technique to treat the constraint of matrix equality. It is shown that the suggested control method can be formulated as linear matrix inequalities that are numerically feasible with commer- cially available software. A numerical example is also given to verify the proposed approach.

关键词： Piecewise affine systems Robust control Observer Linear matrix inequality

Emission and optical characteristics of brown carbon in size-segregated particles from three types of Chinese ships

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Journal of Environmental sciences 2024年第8期142卷 248-258页

作者： Fengqin Yang fan Zhang Zeyu liu Yingjun chen Yan Zhang Can Wu Yali Lei Shijie liu Binyu Xiao Xinyi Wan Yubao chen Yong Han Min Cui cheng Huang Gehui Wang Key Lab of Geographic Information science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China institute of Eco-Chongming 20 Cuiniao Rd.ChongmingShanghai 202150China State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex Shanghai Academy of Environmental SciencesShanghai 200233China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Shanghai institute of Pollution control and Ecological Security Shanghai 200092China department of Civil and Environmental engineering and State Key Laboratory of Marine Pollution The Hong Kong Polytechnic UniversityKowloon 100872Hong KongChina College of Environmental science and engineering Yangzhou UniversityYangzhou 225009China

Brown carbon(BrC)is one of the important light absorption substances that have high light absorption ability under short wavelength ***,limit studies have focused on the BrC emission from *** this study,size-segregated particulate matters(PM)were collected from three different types of ships,light absorption characteristics and size distribution of methanol-soluble BrC and water-soluble BrC in PM from ship exhausts were *** showed that four-stroke low-power diesel fishing boat(4-LDF)had the highest mass concentrations of methanol-soluble organic carbon(MSOC)and water-soluble organic carbon(WSOC),followed by 2-stroke high-power heavy-fuel-oil vessel(2-HHV),and fourstroke high-power marine-diesel vessel(4-HMV).While 2-HHV had obviously higher light absorption coefficients of methanol-soluble BrC(Abs365,M)and water-soluble BrC(Abs365,W)in unit weight of PM than the other two types of *** tested ships presented comparable or higher absorption efficiency of BrC in water extracts(MAE365,W)compared with other BrC emission *** of BrC was concentrated in fine particles,and the particle size distributions of both Abs365,Mand Abs365,Wshowed bimodal patterns,peaking at0.43–0.65μm and 4.7–5.8μm,***,different particle size distributions were found for MAE365,Mbetween diesel and heavy fuel oil ***,different wavelength dependence in particles with different size were also *** exhaust could be confirmed as a non-ignorable BrC emission source,and complex influencing factor could affect the light absorption characteristics of ship *** size should also be considered when light absorption ability of BrC was evaluated.

关键词： Ship emission Brown carbon Light absorption Size distribution

Disturbance Attenuation Property for a Class of Uncertain Discrete-time Linear Switching Systems

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Disturbance Attenuation Property for a Class of Uncertain Di...

LMI-based robust control of uncertain discrete-time piecewise affine systems

第二十九届中国控制会议

作者： fan guowei1,liu zhiyuan1,chen hong2 1.department of control science and engineering,har.in institute of technology,har.in 150001,P.R.china2.department of control science and engineering,Jilin University,Changchun 130025,P.R.china

In this paper,a subclass of switching systems is considered,which is the discrete-time linear switching systems with only in-loop *** the presence of parameter variations and additive l∞ bounded disturbances,the control problem solved consists of determining the non-conservative bounds on the l∞norm of the controlled output,independently of the external uncontrollable event and *** basic idea employed in this paper is to translate the required level of performance into the constraint on the controlled switching systems,then this constraint is considered as the safety problem for this class of switching *** with the bisection method,the optimal level of performance that solves the disturbance attenuation property problem can be *** last,some simulation results are included to show the applicability of the technique.

关键词： Switching Systems Uncertain Systems Disturbance Attenuation Reachability Safety Problem

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控制理论与应用（英文版） 2010年第4期8卷 496-502页

作者： zhiyuan liu Yahui GAO hong chen department of control science and engineering Harbin Institute of Technology Harbin Heilongjiang 150001 China department of control science and engineering Jilin University Changchun Jilin 130025 China

The main contribution of this paper is to present stability synthesis results for discrete-time piecewise affine （PWA） systems with polytopic time-varying uncertainties and for discrete-time PWA systems with norm-bounded uncertainties *** basic idea of the proposed approaches is to construct piecewise-quadratic （PWQ） Lyapunov functions to guarantee the stability of the closed-loop *** partition information of the PWA systems is taken into account and each polytopic operating region is outer approximated by an ellipsoid,then sufficient conditions for the robust stabilization are derived and expressed as a set of linear matrix inequalities （LMIs）.Two examples are given to illustrate the proposed theoretical results.

关键词： Discrete-time systems Linear matrix inequality Piecewise affine systems Piecewise Lyapunov function Robust control

Frontiers in high entropy alloys and high entropy functional materials

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Rare Metals 2024年第10期43卷 4639-4776页

作者： Wen-Tao Zhang Wen Huang Fu-Jie Yu Qi Zhao Xin-Dong Zhu Tao Feng Yao Jiang Xiao-Ming Li Xue-Fei Miao He Zhu Si Lan Xue-Qian Wang Bao-Long Shen Zhe Jia Feng-Qi Zhang Wei Wang Qi liu Yang Ren Xun-Li Wang Xiao-Ya Cui Xiao-Yang Wang Ya-Nan chen Bing-Bing fan Meng-Ru Li Qi-Long Gao Jia-Ming Guo Zeng-Bao Jiao Zhi-Min Guo Yu-Ping Zhao Qian Yu Rui Huang Ling-Kun Zhang Yi-Ping Lu Xu-Bo Li Huai-Jun Lin Yan Ma Wei-Ming Yang Zhi-Hua Shen Hai-Yan He Yong-Gang Sun Yong-Jiang Huang De-Zhuang Wang Qing-Feng liu Fei-Yang Wang Hui liu hong-Hui Wu Li-Qiang Wang Yang Lu Nan Wang Tian-Li Wang Wei-Bing Liao Yi-Han Wang Yuan Wu Yu-Zhen Yin Jie Pan Yi Zhang Qing Wang Jian-Yang Zhang Tao Yang Yasir Sohail Jin-Yu Zhang Hua Ji Qiang Li Wei-Di liu Zhi-Gang chen Xiong-Jun liu Wen Ma Liang Mao Zhen-Duo Wu School of Materials science and engineering Nanjing University of Science and Technology Jiangsu Key Laboratory for Advanced Metallic Materials School of Materials Science and Engineering Southeast University department of Physics City University of Hong Kong School of Materials science and engineering Tianjin University School of Physics and Microelectronics Zhengzhou University department of Mechanical engineering Research Institute for Advanced Manufacturing The Hong Kong Polytechnic University Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University Key Laboratory of Solidification control and Digital Preparation technology (Liaoning Province) School of Materials Science and Engineering Dalian University of Technology institute of Advanced Wear & Corrosion Resistance and Functional Materials Jinan University School of Mechanics and Civil engineering China University of Mining and Technology School of Physical sciences Great Bay University School of Materials science andengineering Harbin Institute of Technology State Key Laboratory of Materials-Oriented Chemical engineering College of Chemical Engineering Nanjing Tech University Beijing Advanced Innovation Center for Materials Genome engineering Research Institute for Carbon Neutrality University of Science and Technology Beijing department of Mechanical engineering The University of Hong Kong School of Computing Macquarie University Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing State Key Laboratory of Materials Processing and Die & Mould technology School of Materials Science and Engineering Huazhong University of Science and Technology institute of materials Shanghai University department of Materials science and engineering C

Owing to their exceptional properties, high-entropy alloys(HEAs) and high-entropy materials have emerged as promising research areas and shown diverse applications. Here,the recent advances in the field are comprehensively reviewed,organized into five sections. The first section introduces the background of HEAs, covering their definition, significance,application prospects, basic properties, design principles, and microstructure. The subsequent section focuses on cutting-edge high-entropy structural materials, highlighting developments such as nanostructured alloys, grain boundary engineering,eutectic systems, cryogenic alloys, thin films, micro-nano-lattice structures, additive manufacturing, high entropy metallic glasses, nano-precipitate strengthened alloys, composition modulation, alloy fibers, and refractory systems. In the following section, the emphasis shifts to functional materials, exploring HEAs as catalysts, magneto-caloric materials, corrosion-resistant alloys, radiation-resistant alloys, hydrogen storage systems, and materials for biomedicine. Additionally, the review encompasses functional high-entropy materials outside the realm of alloys, including thermoelectric, quantum dots, nanooxide catalysts, energy storage materials, negative thermal expansion ceramics,and high-entropy wave absorption materials. The paper concludes with an outlook, discussing future directions and potential growth areas in the field. Through this comprehensive review,researchers, engineers, and scientists may gain valuable insights into the recent progress and opportunities for further exploration in the exciting domains of high-entropy alloys and functional materials.

关键词： Cutting-edge structural materials Cutting-edgefunctional materials High entropy alloys

Artificial intelligence for geoscience:Progress,challenges,and perspectives

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The Innovation 2024年第5期5卷 136-160,135页

作者： Tianjie Zhao Sheng Wang Chaojun Ouyang Min chen chenying liu Jin Zhang Long Yu Fei Wang Yong Xie Jun Li fang Wang Sabine Grunwald Bryan MWong fan Zhang Zhen Qian Yongjun Xu chengqing Yu Wei Han Tao Sun Zezhi Shao Tangwen Qian Zhao chen Jiangyuan Zeng Huai Zhang Husi Letu Bing Zhang Li Wang Lei Luo Chong Shi hongjun Su hongsheng Zhang Shuai Yin Ni Huang Wei Zhao Nan Li Chaolei Zheng Yang Zhou Changping Huang Defeng Feng Qingsong Xu Yan Wu Danfeng hong Zhenyu Wang Yinyi Lin Tangtang Zhang Prashant Kumar Antonio Plaza Jocelyn Chanussot Jiabao Zhang Jiancheng Shi Lizhe Wang Aerospace Information Research institute Chinese Academy of SciencesBeijing 100094China School of Computer science China University of GeosciencesWuhan 430078China State Key Laboratory of Mountain Hazards and engineering Resilience Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China Key Laboratory of Virtual Geographic Environment(Ministry of Education of PRC) Nanjing Normal UniversityNanjing 210023China Data science in Earth Observation Technical University of Munich80333 MunichGermany The National Key Laboratory of Water Disaster Prevention Yangtze Institute for Conservation and DevelopmentHohai UniversityNanjing 210098China institute of Computing technology Chinese Academy of SciencesBeijing 100190China School of Geographical sciences Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Soil Water and Ecosystem Sciences DepartmentUniversity of FloridaPO Box 110290GainesvilleFLUSA Materials science engineering Program Cooperating Faculty Member in the department of Chemistry and department of Physics Astronomy University of CaliforniaCaliforniaRiversideCA 92521USA institute of Remote Sensing and Geographical Information System School of Earth and Space SciencesPeking UniversityBeijing 100871China Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China International Research Center of Big Data for Sustainable Development Goals Beijing 100094China College of Geography and Remote Sensing Hohai UniversityNanjing 211100China department of Geography The University of Hong KongHong Kong 999077SARChina Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution control Nanjing 210044China School of Environmental science and engineering Nanjing University of Information Science&TechnologyNanjing 210044China Collaborative Inno

This paper explores the evolution of geoscientific inquiry,tracing the progression from traditional physics-based models to modern data-driven approaches facilitated by significant advancements in artificial intelligence(AI)and data collection *** models,which are grounded in physical and numerical frameworks,provide robust explanations by explicitly reconstructing underlying physical ***,their limitations in comprehensively capturing Earth’s complexities and uncertainties pose challenges in optimization and real-world *** contrast,contemporary data-driven models,particularly those utilizing machine learning(ML)and deep learning(DL),leverage extensive geoscience data to glean insights without requiring exhaustive theoretical *** techniques have shown promise in addressing Earth science-related ***,challenges such as data scarcity,computational demands,data privacy concerns,and the“black-box”nature of AI models hinder their seamless integration into *** integration of physics-based and data-driven methodologies into hybrid models presents an alternative *** models,which incorporate domain knowledge to guide AI methodologies,demonstrate enhanced efficiency and performance with reduced training data *** review provides a comprehensive overview of geoscientific research paradigms,emphasizing untapped opportunities at the intersection of advanced AI techniques and *** examines major methodologies,showcases advances in large-scale models,and discusses the challenges and prospects that will shape the future landscape of AI in *** paper outlines a dynamic field ripe with possibilities,poised to unlock new understandings of Earth’s complexities and further advance geoscience exploration.

关键词： Earth utilizing landscape

Additive manufacturing of metals:Microstructure evolution and multistage control

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Journal of Materials science & technology 2022年第5期100卷 224-236页

作者： zhiyuan liu Dandan Zhao Pei Wang Ming Yan Can Yang Zhangwei chen Jian Lu Zhaoping Lu Additive Manufacturing institute College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China department of Materials science and engineering Southern University of Science and TechnologyShenzhen 518055China Sino-German College of Intelligent Manufacturing Shenzhen Technology UniversityShenzhen 518118China CityU-Shenzhen Futian Research institute Shenzhen 518045China hong Kong Branch of National Precious Metals Material engineering Research Center(NPMM) City University of Hong KongHong KongChina Beijing Advanced Innovation Center for Materials Genome engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China

As a revolutionary industrial technology,additive manufacturing creates objects by adding materials layer by layer and hence can fabricate customized components with an unprecedented degree of *** metallic materials,unique hierarchical microstructures are constructed during additive manufacturing,which endow them with numerous excellent *** take full advantage of additive manufacturing,an in-depth understanding of the microstructure evolution mechanism is *** this end,this review explores the fundamental procedures of additive manufacturing,that is,the formation and binding of melt pools.A comprehensive processing map is proposed that integrates melt pool energy-and geometry-related process parameters *** on it,additively manufactured microstructures are developed during and after the solidification of constituent melt *** solidification structures are composed of primary columnar grains and fine secondary phases that form along the grain *** post-solidification structures include submicron scale dislocation cells stemming from internal residual stress and nanoscale precipitates induced by intrinsic heat treatment during cyclic heating of adjacent melt *** on solidification and dislocation theories,the formation mechanisms of the multistage microstructures are thoroughly analyzed,and accordingly,multistage control methods are *** addition,the underlying atomic scale structural features are briefly ***,microstructure design for additive manufacturing through adjustment of process parameters and alloy composition is addressed to fulfill the great potential of the *** review not only builds a solid microstructural framework for metallic materials produced by additive manufacturing but also provides a promising guideline to adjust their mechanical properties.

关键词： Additive manufacturing Metallic materials Melt pool Processing map Microstructure evolution

Projections of heat-related excess mortality in china due to climate change,population and aging

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Frontiers of Environmental science & engineering 2023年第11期17卷 145-155页

作者： Zhao liu Si Gao Wenjia Cai Zongyi Li Can Wang Xing chen zhiyuan Ma Zijian Zhao School of Airport Economics and Management Beijing Institute of Economics and ManagementBeijing 100102China department of Earth System science Institute for Global Change StudiesMinistry of Education Ecological Field Station for East Asian Migratory BirdsTsinghua UniversityBeijing 100084China School of Land science and technology China University of Geosciences(Beijing)Beijing 100083China State Key Joint Laboratory of Environment Simulation and Pollution control(SKLESPC) and School of EnvironmentTsinghua UniversityBeijing 100084China Global Energy Interconnection Development and Cooperation Organization(GEIDCO) Beijing 100052China

Climate change is one of the biggest health threats of the 21st *** china is the biggest developing country,with a large population and different climate types,its projections of large-scale heat-related excess mortality remain *** particular,the effects of climate change on aging populations have not been well studied,and may result in significantly underestimation of heat *** this study,we took four climate change scenarios of Tier-1 in CMIP6,which were combinations of Shared Socioeconomic Pathways(SSPs)and Representative Concentration Pathways(RCPs).We used the exposure-response functions derived from previous studies combined with baseline age-specific non-accidental mortality rates to project heat-related excess ***,we employed the Logarithmic Mean Divisia Index(LMDI)method to decompose the impacts of climate change,population growth,and aging on heat-related excess ***,we multiplied the heat-related Years of Life Lost(YLL)with the Value of a Statistical Life Year(VSLY)to quantify the economic burden of premature *** found that the heat-related excess mortality would be concentrated in central china and in the densely populated south-eastern coastal *** aging is considered,heat-related excess mortality will become 2.8–6.7 times than that without considering aging in 2081–2100 under different *** contribution analysis showed that the effect of aging on heat-related deaths would be much higher than that of climate *** findings highlighted that aging would lead to a severe increase of heat-related deaths and suggesting that regional-specific policies should be formulated in response to heat-related risks.

关键词： Heat-related excess mortality LMDI Aging YLL VSLY

Feedback control of Discrete Linear Switching Systems with Bounded State and control Input in the Presence of Disturbances

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自动化学报 2010年第8期36卷 1115-1121页

作者： fan Guo-Wei liu Zhi-Yuan chen hong department of control science and engineering Harbin Institute of Technology Harbin 150001 P.R. China department of control science and engineering Jitin University Changchun 130025 P.R. China

The main contribution of this paper is to present some stability synthesis results for a subclass of hybrid systems, which is the discrete-time linear switching systems whose dynamics contain reset functions and are determined by exogenous and uncontrollable events. In the presence of additive bounded disturbances, with state and control input constraints, the linear state feedback controller design that can stabilize the system is investigated in the sense of input-to-state stability(ISS).The concept of controlled D-invariance is introduced for this class of hybrid systems, and a necessary and su-cient condition to test the controlled D-invariance of a hybrid region is given. After this,a procedure for the computation of the feedback matrices, which can stabilize the disturbed linear switching systems and also satisfy the state and control input constraints,is proposed. Finally,a numerical example made up of two subsystems is given to show the applicability of the technique

关键词：反馈控制器自动化系统稳定性动力学