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Analysis of Topological Structure in Transiently Chaotic Neural Networks

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Acta Mathematicae Applicatae Sinica 2018年第3期34卷 610-621页

作者： Yang GAO Zuo-huan zheng Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences

Under the condition that the damping factor is between zero and one, chaotic dynamics is proved to exist in one-dimensional transiently chaotic neural networks by Li-Misiurewicz theorem. This result extends the previous result which is done under the condition that the damping factor is zero. Because the value of damping factor affects the speed of dynamical process of transiently chaotic neural networks, this result provides more complete theoretical basis for applications. Finally, two examples by numerical simulation are given to reinforce and illustrate this result.

关键词： transiently chaotic neural networks Li-Yorke chaos no division

Selective N-Methylation of N-Methylaniline with CO_(2) and H_(2) over Cu/In_(2)O_(3) Catalyst

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Chinese Journal of Chemistry 2024年第3期42卷 276-282页

作者： huan zheng Bo Qian Lin He State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of Chinese Academy of Sciences Beijing100049 China

N-Methylation of amines with CO_(2) and H2 is a potential approach for CO_(2) utilization because N-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported Cu (Cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for N-methylation reaction of N-methylaniline (MA) with CO_(2) and H_(2),showing higher N,N-dimethylaniline (DMA) selectivity than other supported Cu catalysts. On one hand,the dispersion of Cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of CO_(2) through C—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by Cu. The combination of Cu and In_(2)O_(3) is effective in the activation of CO_(2),the adsorption of intermediate N-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of C—N bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： N-Methylation CO_(2) Cu/In_(2)O_(3) Supported catalysts Heterogeneous catalysis

Uniform and Semi-uniform Convergence for Discontinuous Skew-product Transformation and Observation

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Acta Mathematica Sinica,English Series 2021年第2期37卷 333-344页

作者： Xia PAN Zuo huan zheng Zhe ZHOU College of Liberal Arts and Sciences National University of Defense TechnologyChangsha 410073P.R.China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190P.R.China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China ollege of Mathematics and Statistics Hainan Normal UniversityHaikou 571158P.R.China

In this paper, for a discontinuous skew-product transformation with the integrable observation function, we obtain uniform ergodic theorem and semi-uniform ergodic theorem. The main assumptions are that discontinuity sets of transformation and observation function are ignorable in some measure-theoretical sense. The theorems extend the classical results which have been established for continuous transformations and continuous observation functions.

关键词： Skew-product transformation uniform ergodicity semi-uniform ergodicity

A Note on Equilibrium of Eventually Strongly Monotone Skew-product Semiflows

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Acta Mathematicae Applicatae Sinica 2010年第2期26卷 307-310页

作者： Xi-liang Li Zuo-huan zheng Shandong Institute of Business and Technology Yantai 264005 China Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190 China

In this paper, we show that for an eventually strongly monotone skew-product semiflow τ, the strict ordering on Ec （the set consisting of continuous equilibria of τ） implies the strong one.

关键词： continuous equilibrium eventually strongly monotone skew-product semiflow

Almost Periodic Solutions by the Harmonic Balance Method

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Acta Mathematicae Applicatae Sinica 2022年第4期38卷 943-954页

作者： Ji-feng CHU Zuo-huan zheng Zhe ZHOU Department of Mathematics Shanghai Normal UniversityShanghai 200234China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China College of Mathematics and Statistics Hainan Normal UniversityHaikou 571158China

We consider non-autonomous ordinary differential equations in two *** is the one-dimensional case that admits a condition of hyperbolicity,and the other one is the higher-dimensional case that admits an exponential *** differential equations of this kind,we give a rigorous treatment of the Harmonic Balance Method to look for almost periodic solutions.

关键词： almost periodic solution Harmonic balance method exponential dichotomy

A New Information Method to Determinate Corrosion Types from Electrochemical Noise

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 449-453页

作者： Jian Li huan-Jun zheng Ye zheng Wei-Kang Kong Ke Wang State Key Laboratory of Precision Measuring Technology and Instrument Tianjin University School of Materials Science and Engineering Tianjin University

Electrochemical noise data in the presence of different corrosion types were analyzed. A correlation between the corrosion type of the observed noise and the entropy rate was recognized. A sequence was transformed from each set of original electrochemical noise signal, then the Markov process M and stationary distribution μ were calculated. Finally, entropy rate of each sequence was obtained by the definition. From the entropy rate, it has been observed that local corrosion showed a lower entropy rate, while uniform corrosion showed a higher entropy rate.

关键词： Entropy rate Stainless steel Corrosion Electrochemical behavior

A Mathematical Model of the Photosynthetic Carbon Metabolism Has Multiple Steady States Under the Same Parameter Conditions

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 591-604页

作者： Jin-ling ZHOU Zuo-huan zheng Xin-guang ZHU Institute of Science and Technology Zhejiang International Studies University. Hangzhou 310012 China Institute of Applied Mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sciences. Beijing 100080 China CAS-MPG Partner Institute for Computational Biology and Key Laboratory for Computational Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

This paper analyzes a mathematical model of the photosynthetic carbon metabolism, which incorporates not only the Calvin-Benson cycle, but also another two important metabolic pathways： starch synthesis and photorespiratory pathway. Theoretically, the paper shows the existence of steady states, stability and instability of the steady states, the effects of CO2 concentration on steady states. Especially, a critical point is found, the system has only one steady state with C02 concentration in the left neighborhood of the critical point, but has two with C02 concentration in the right neighborhood. In addition, the paper also explores the influence of C02 concentration on the efficiency of photosynthesis. These theoretical results not only provide insight to the kinetic behaviors of the photosynthetic carbon metabolism, but also can be used to help improving the efficiency of photosynthesis in plants.

关键词： photosynthesis the efficiency of photosynthesis multiple steady states stability critical point

Assessment of Building Physical Vulnerability in Earthquake‑Debris Flow Disaster Chain

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International Journal of Disaster Risk Science 2023年第4期14卷 666-679页

作者： Hao zheng Zhifei Deng Lanlan Guo Jifu Liu Lianyou Liu Tiewei Li huan zheng Tao zheng Key Laboratory of Environmental Change and Natural Disaster of Ministry of Education Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Academy of Disaster Reduction and Emergency Management Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Department of Fire Commanding China Fire and Rescue InstituteBeijing 102202China China Railway First Group Construction and Installation Engineering Co. Ltd.Xi’an 710054China

Large earthquakes not only directly damage buildings but also trigger debris fows,which cause secondary damage to buildings,forming a more destructive earthquake-debris fow disaster chain.A quantitative assessment of building vulnerability is essential for damage assessment after a disaster and for pre-disaster *** mechanical analysis based on pushover,a physical vulnerability assessment model of buildings in the earthquake-debris fow disaster chain is proposed to assess the vulnerability of buildings in Beichuan County,*** on the specifc sequence of events in the earthquake-debris fow disaster chain,the seismic vulnerability of buildings is 79%,the fow impact and burial vulnerabilities of damaged buildings to debris fow are 92%and 28%respectively,and the holistic vulnerability of buildings under the disaster chain is 57%.By comparing diferent vulnerability assessment methods,we observed that the physical vulnerability of buildings under the disaster chain process is not equal to the statistical summation of the vulnerabilities to independent hazards,which implies that the structural properties and vulnerability of buildings have changed during the disaster chain *** results provide an integrated explanation of building vulnerability,which is essential for understanding building vulnerability in earthquake-debris fow disaster chain and building vulnerability under other disaster chains.

关键词： Building physical vulnerability Debris fow Disaster chain Earthquake

Optimal Content Placement and Request Dispatching for Cloud-based Video Distribution Services

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International Journal of Automation and computing 2016年第6期13卷 529-540页

作者： zheng-huan Zhang Xiao-Feng Jiang Hong-Sheng Xi Department of Automation University of Science and Technology of China

The rapid progress of cloud technology has attracted a growing number of video providers to consider deploying their streaming services onto cloud platform for more cost-effective, scalable and reliable performance. In this paper, we utilize Markov decision process model to formulate the dynamic deployment of cloud-based video services over multiple geographically distributed datacenters. We focus on maximizing the average profits for the video service provider over a long run and introduce an average performance criteria which reflects the cost and user experience jointly. We develop an optimal algorithm based on the sensitivity analysis and sample-based policy iteration to obtain the optimal video placement and request dispatching strategy. We demonstrate the optimality of our algorithm with theoretical proof and specify the practical feasibility of our algorithm. We conduct simulations to evaluate the performance of our algorithm and the results show that our strategy can effectively cut down the total cost and guarantee users＇ quality of experience （QoE）.

关键词： Cloud computing video distribution Markov decision process sensitivity analysis policy iteration.