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Crowd queuing simulation with an improved emotional contagion model

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Science China(Information Sciences) 2019年第4期62卷 197-199页

作者： Junxiao XUE Hui yin pei LV Mingliang XU Yafei LI School of Software Zhengzhou University School of Information Engineering Zhengzhou University

In crowd queuing events, the emotions of individuals are mutually infective, easily confusing the queuing order and possibly leading to crowd events. However, the impact of emotion and personality is not considered in... 详细信息

关键词： Crowd queuing simulation with an improved emotional contagion model

An Equivalent Condition for the Self Similar Sets on the Real Line to Have Best Coverings

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Acta Mathematica Sinica,English Series 2013年第9期29卷 1637-1646页

作者： Jian dong yin Zuo Ling ZHOU Department of Mathematics Nanchang University Lingnan College Zhongshan University

In this paper, an equivalent condition for the self similar sets on the real line to have best coverings is given. As a result, it partly gives answer to the conjecture which was posed by Zhou and Feng [Zhou, Z. L., Feng, L.： Twelve open problems on the exact value of the Hausdorff measure and on topological entropy： A brief survey of recent results. Nonlinearity, 17（2）, 493-502 （2004）].

关键词： Self similar set open set condition upper convex density best covering

Urban natural gas demand and factors analysis in China:Perspectives of price and income elasticities

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Petroleum Science 2022年第1期19卷 429-440页

作者： Jia-Man Li Xiu-Cheng dong Qin-Zhe Jiang Kang-yin dong School of International Trade and Economics University of International Business and EconomicsBeijing100029China UIBE Belt&Road Energy Trade and Development Center University of International Business and EconomicsBeijing100029China

Urban natural gas is becoming the main sector driving China’s natural gas consumption growth in recent *** study explores the impacts of urban natural gas price,wage,socioeconomic determinants,and meteorological conditions on urban natural gas demand in China over ***,this study also analyzes the potential regional heterogeneity and asymmetry in the impacts of gas price and income on China’s urban gas *** results reveal that:(1)The increased gas price can significantly reduce the urban gas demand,and the average income level may effectively promote the gas demand,also,a strong switching effect exists between electricity and natural gas in urban China;(2)these impacts are heterogeneous in regions among China,urban natural gas demand is largely affected by the gas price in regions with high-gas-price and by income in regions with low-gas-price;and(3)the impact of gas price on urban gas consumption is consistent in regions with different urban natural gas consumption,while the impact of income is *** study further provides several policy implications for improving the urban natural gas industry in China.

关键词： Urban natural gas demand Natural gas price Average wage Regional heterogeneity Asymmetry analysis

The Global Convergence of Self-Scaling BFGS Algorithm with Nonmonotone Line Search for Unconstrained Nonconvex Optimization Problems

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Acta Mathematica Sinica,English Series 2007年第7期23卷 1233-1240页

作者： Hong Xia yin dong Lei DU Chinese Academy of Sciences Research Center on Data Technology and Knowledge Economy Department of Mathematics Graduate University of the Chinese Academy of Sciences Faculty of Administration University of New Brunswick

The self-scaling quasi-Newton method solves an unconstrained optimization problem by scaling the Hessian approximation matrix before it is updated at each iteration to avoid the possible large eigenvalues in the Hessian approximation matrices of the objective function. It has been proved in the literature that this method has the global and superlinear convergence when the objective function is convex （or even uniformly convex）. We propose to solve unconstrained nonconvex optimization problems by a self-scaling BFGS algorithm with nonmonotone linear search. Nonmonotone line search has been recognized in numerical practices as a competitive approach for solving large-scale nonlinear problems. We consider two different nonmonotone line search forms and study the global convergence of these nonmonotone self-scale BFGS algorithms. We prove that, under some weaker condition than that in the literature, both forms of the self-scaling BFGS algorithm are globally convergent for unconstrained nonconvex optimization problems.

关键词： nonmonotone line search self-scaling BFGS method global convergence

A novel architecture of electro-hydrostatic actuator with digital distribution

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Chinese Journal of Aeronautics 2021年第5期34卷 224-238页

作者： Jing YAO pei WANG Zhaosheng dong dongting JIANG Tong SHA School of Mechanical Engineering Yanshan UniversityQinhuangdcio 066004China Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education of China Ycmshan UniversityQinhuangdao 066004China Hebei Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Ycmshan UniversityQinhuangdao 066004China

To address the flow imbalance rapidly of the asymmetric Electro-Hydrostatic Actuator(EHA),this paper presents a novel architecture of asymmetric EHA with the Digital Distribution(EHA-DD).It also improves the flow nonlinearity and control accuracy of the pump,especially in the low-speed *** digital distribution with two High-Speed on–off Valves(HSVs)not only balances flow instead of the check valves,but also replaces the pump at the low-speed to control output flow by adjusting the PWM *** pump and HSVs are the crucial components to control flow ***,the flow calculation models of the pump and the duty ratio inversed model of the HSV are obtained through experimental tests and the identification *** get the control input signal for the required flow,the pump speed and PWM duty ratio for the HSVs are inversed to compensate for flow ***,a multimode digital flow distribution control method based on pump speed,mainly including the pump-controlled mode for large flow demand and valve-controlled mode for little flow demand,is proposed to control the accurate flow output *** step extension experiments based on the flow calculation models are conducted on the EHA-DD prototype under elastic,opposite varying *** results demonstrate that the EHADD realizes little position error by accurate flow control,and it is also beneficial to improve the service life of the pump.

关键词： Asymmetrical flow Digital distribution EHA High-speed on–off valve Nonlinearity PWM control

Operational Control of Low-voltage MTDC Systems in a Cyber-physical Environment

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1569-1582页

作者： Wei Deng Wei pei Ningning Li Xue Zhang yin Yi Li Kong Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication Engineering(EECE)University of Chinese Academy of SciencesBeijing 100049China

Based on the standardized cyber-physical modeling and communication system-IEC 61850,this paper establishes the operational control architecture of a low-voltage multi-terminal DC(LV-MTDC)*** coordinated operational control strategies,including power electronic transformer(PET),and voltage source converter(VSC),are *** a cyberphysical model of the system based on IEC 61850 is built,according to the application requirements of operational control in the LV-MTDC *** this basis,the implementation method of system operational control based on IEC 61850 is proposed,including the software/hardware design of the intelligent electronic device(IED),dispatching operations and uninterrupted power *** simulation environment is further built to verify the system operational control technology,and the test platform is used to carry out the actual *** research results show that the operational control technology for the LV-MTDC system proposed in this paper is feasible,which can guarantee the rapid and accurate information exchange of control commands and settings,and thus effectively realize the operational control of the LV-MTDC system under complex conditions.

关键词： Cyber-physical system distributed energy resources IEC 61850 intelligent electronic device low-voltage multi-terminal DC system

Two New d10 Supramolecular Polymers Constructed by 1H-Pyrazolo[3,4-b]pyridin-3-amine and 1,4-Benzenedicarboxylic Acids

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Chinese Journal of Structural Chemistry 2019年第6期38卷 901-908页

作者： XU Yun DING Fang LIU dong YANG pei-pei College of Chemistry and Materials Science Huaibei Normal University

Two new coordination polymers, [Cd(BDC)(HL)]n(I) and {[Zn(BDC)(HL)2]·(H2 O)}n(Ⅱ), have been synthesized under solvothermal conditions, based on 1 H-pyrazolo[3,4-b]pyridin-3-amine(HL) along with 1,4-benzenedicarboxylic acid(H2 BDC). Polymers I and Ⅱ have been characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction analysis. Polymer I features a two-dimensional 4-connected sql structure and further extends into a three-dimensional supramolecular framework directed by hydrogen-bonding interactions and π-π interactions. Polymer Ⅱ exhibits a layered packing supramolecular structure. Hydrogen bonding interactions involved between the free water molecules and carboxylate O atoms of H2 BDC ligands as well as the amino N atom of HL ligands play a critical role in constructing the three-dimensional supramolecular structure of Ⅱ. The solid-state photoluminescent properties of the two polymers were also investigated.

关键词： 1H-pyrazolo[3,4-b]pyridin-3-amine supramolecular structure hydrogen-bonding interactions

1,1-Regioselective alkenylboration of styrenes enabled by palladium catalysis

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Chinese Chemical Letters 2023年第8期34卷 175-179页

作者： dong Wu Hailiang Pang Guoyin yin The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

Despite the 1,2-difunctionalization reactions of styrenes have been well developed, the 1,1-regioselective addition reaction remains challenging. We disclose herein a palladium-catalyzed, highly 1,1-regioselective alkenylboration of styrenes by using alkenyl triflates and a diboron reagent as the coupling partners. A wide scope of styrenes derivatives and alkenyl triflates participate this reaction to provide the corresponding allyl boronates with high regioisomeric ratios. The success of this reaction is ascribed to the application of 1,10-phenanthroline-derivated ligand and the addition of ammonium chloride salt. Moreover, acrylate esters can also selectively afford the 1,1-alkenylboration products under the same reaction conditions.

关键词： Styrenes 1,1-Regioselectivity Chain-walking Palladium catalysis Allyl boronates

Evidence on the causes of the rising levels of COD_(Mn) along the middle route of the South-to-North Diversion Project in China:The role of algal dissolved organic matter

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Journal of Environmental Sciences 2022年第3期34卷 281-290页

作者： Chao Wang Hong Zhang pei Lei Xiaokang Xin Aijing Zhang Wei yin Changjiang Water Resources Protection Institute Wuhan 430051China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Pollution Control and Resources Reuse School of the EnvironmentNanjing UniversityNanjing 210046China Construction and Administration Bureau of South-to-North Water Diversion Middle Route Project Beijing 100038China Key Laboratory cf Ecological Regulation ofNon-point Source Pollution in Lake and Reservoir Water Sources Wuhan 430051China

As the biggest inter-basin water transfer scheme in the world,the South-to-North Water Diversion Project(SNWD) was designed to alleviate the water crisis in North *** main channel of the middle route of the SNWD is of great concern in terms of the drinking water *** this study,we tested the hypothesis that the dissolved organic matter(DOM) derived from the planktonic algae causes the rising levels of COD_(Mn) along the middle route by monitoring data on water quality(2015-2019,monthly resolution).The results showed that algal density in the main channel increased along the channel and was significantly correlated with COD_(Mn)(p <0.01).Five fluorescent components of DOM,including tyrosine-like(14.85%),tryptophan-like(22.48%),microbial byproduct-like(26.34%),fulvic acid-like(11.41%),and humic acid-like(24.92%) components,were *** level of tyrosine-like components increased along the channel and was significantly correlated with algal density(p<0.01),indicating that algae significantly changed the level of DOM in the *** decomposition and metabolism were found to be the main mechanisms that drive the changes in COD_(Mn).Therefore,controlling algal density would be an important measure to prevent further increase in CODMn and for the guarantee of excellent water quality.

关键词： Dissolved organic matter(DOM)Algae COD_(Mn) South-to-North Diversion Project Danjiangkou reservoir Three-dimensional fluorescence excitation emission matrix spectroscopy(3D-EEMs)