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Statistical Physics of Economic Systems: a Survey for Open Economies

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Chinese Physics Letters 2012年第5期29卷 248-251页

作者： TAO Yong chen xun School of Economics and Business Administration Chongqing UniversityChongqing 400044

We extend the theoretical framework of an independent economy developed by Tao [***.E 82 (2010) 036118]so as to include multiple *** the starting point of our framework is on the basis of the theory of the competitive markets of traditional economics,this framework shall be suitablefor any free *** study shows that integration of world economies can decrease trade friction among economic systems,but may also cause a global economic crisis whenever economy disequilibrium occurs in any one of these economic systems.

关键词： whenever starting competitive

p-arrangeable Graphs are Folkman Linear

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 69-74页

作者： xun chen Qi-zhong LIN Center for Discrete Mathematics Fuzhou UniversityFuzhou 350108 China

For graphs F and G,let F→(G,G)denote that any red/blue edge coloring of F contains a monochromatic *** Folkman number f(G;t)to be the smallest order of a graph F such that F→(G,G)andω(F)≤*** is shown that f(G;t)≤... 详细信息

关键词： Folkman number Folkman linear Multi-partite regularity lemma

Method for maneuvering target video frequency tracking based on inductive factor of posture information

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Journal of Systems Engineering and Electronics 2010年第2期21卷 261-267页

作者： xun chen Lihua Dou Juan Zhang Department of Automatic Control School of Information Science and Technology Beijing Institute of Technology Beijing 100081 P. R. China

A method for maneuvering target tracking based on in- ductive factor of posture information is proposed. A distinguished charactedstic of video frequency tracking is that it can capture the target posture changes from its picture easily, and the posture change means the motive model of the target will change. This information is very important to predict the trace of maneuvering target. Based on this idea, the quantified values of the target pos- ture change are obtained using Hough algorithm, this key values are defined as inductive factor of posture information, and then, the multiple grey trace predict models are established and the degrees of fuzzy subordinate values for every model are calculated with the inductive factor, the maneuvering extent values are determined by a new analysis method of stochastic differential equations for each model used to modify the degree of fuzzy subordinate values, these constitute the weighted values for every grey predict collec- tion. Finally, the synthesis predicting weighted result is obtained. The experimental results show that the new method is superior to the conventional algorithm.

关键词： target posture grey prediction hough algodthm de- gree of fuzzy subordinate.

Analysis of Incomplete Data of Accelerated Life Testing with Competing Failure Modes

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 883-889页

作者： TAN Yuanyuan ZHANG Chunhua chen xun College of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China

Data obtained from accelerated life testing （ALT） when there are two or more failure modes, which is commonly referred to as competing failure modes, are often incomplete. The incompleteness is mainly due to censoring, as well as masking which might be the case that the failure time is observed, but its corresponding failure mode is not identified. Because the identification of the failure mode may be expensive, or very difficult to investigate due to lack of appropriate diagnostics. A method is proposed for analyzing incomplete data of constant stress ALT with competing failure modes. It is assumed that failure modes have s-independent latent lifetimes and the log lifetime of each failure mode can be written as a linear function of stress. The parameters of the model are estimated by using the expectation maximum （EM） algorithm with incomplete data. Simulation studies are performed to check＇model validity and investigate the properties of estimates. For further validation, the method is also illustrated by an example, which shows the process of analyze incomplete data from ALT of some insulation system. Because of considering the incompleteness of data in modeling and making use of the EM algorithm in estimating, the method becomes more flexible in ALT analysis.

关键词： accelerated life testing competing failure modes expectation maximum algorithm incomplete data Monte Carlo simulation

Reliability Analysis of Electromechanical Systems with Degraded Components Containing Multiple Performance Parameters

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 511-516页

作者： LI Chunyang chen xun YI Xiaoshan College of Mechatronics and Automation National University of Defense Technology Changsha 410073 China

Components of electromechanical systems usually contain multiple performance parameters and degrade over time. In previous studies, the reliability of these electromechanical systems was analyzed by the traditional method, and the system reliability was estimated based on the reliability of components and the structures of the systems. The system reliability estimated by the traditional method could not reflect the performance of the systems. A new method is proposed in this paper to analyze the system reliability according to the data of multiple performance degraded processes of components. The performance distribution of a degraded component is obtained by the performance degradation analysis, and then states of the component are defined and corresponding state probabilities are estimated. The universal generating function method is proposed and extended to compute the performance distribution and reliability of the system based on the performances of components. A numerical example illustrates the proposed method. The results of the example show that the proposed method can relate the performance of the system to the performances of components and absolutely reflect the relationship between reliability and performance. Compared with the exact values of the system reliability, the results obtained by the proposed method is almost the same with the exact values, and the results obtained by the traditional method are conservative. The proposed method overcomes the shortcomings of the traditional method and provides a new approach to analyze the reliability of electromechanical systems with degraded components containing multiple performance parameters.

关键词： electromechanical system degradation reliability analysis multi-state system universal generating function

Enhanced copper recovery from low grade copper sulfide ores through bioleaching using residues produced by fermentation of agricultural wastes

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International Journal of Minerals,Metallurgy and Materials 2022年第12期29卷 2136-2143页

作者： Wei chen Shenghua Yin Qing Song Leiming Wang xun chen Key Laboratory of Ministry of Education for High-Efficient Mining and Safety of Metal University of Science and Technology BeijingBeijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China

Effects of residues produced by agricultural wastes fermentation(AWF)on low grade copper sulfide ores bioleaching,copper recovery,and microbial community were *** results indicated that adding appropriate bulk of AWF made contributions to low grade copper sulfide ores bioleaching,which may be mainly realized through reducing the passivation layer formed by Fe3+*** copper recovery(78.35%)and bacteria concentration(9.56×10^(7)cells·mL^(−1))were yielded in the presence of 5 g·L^(−1)*** result of 16S rDNA analysis demonstrated that microbial community was differentiated by adding *** proportion,such as Acidithiobacillus ferrooxidans,Moraxella osloensis,and Lactobacillus acetotolerans changed *** difference between samples was showed according to beta diversity index,and the maximum value reached *** ferrooxidans accounted for the highest proportion throughout the bioleaching process,and that of sample in the presence of 5 g·L^(−) AWF reached 28.63%.The results should show reference to application of agricultural wastes and low grade copper sulfide ores.

关键词： low grade copper sulfide ores bioleaching agricultural wastes fermentation microbial community

production of extracellular lysophosphatidic acid in the regulation of adipocyte functions and liver fibrosis

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World Journal of Gastroenterology 2018年第36期24卷 4132-4151页

作者： Fang Yang Guo-xun chen School of Laboratory Medicine Hubei University of Chinese Medicine Department of Nutrition University of Tennessee at Knoxville

Lysophosphatidic acid(LPA), a glycerophospholipid, consists of a glycerol backbone connected to a phosphate head group and an acyl chain linked to sn-1 or sn-2 position. In the circulation, LPA is in submillimolar range and mainly derived from hydrolysis of lysophosphatidylcholine, a process mediated by lysophospholipase D activity in proteins such as autotaxin(ATX). Intracellular and extracellular LPAs act as bioactive lipid mediators with diverse functions in almost every mammalian cell type. The binding of LPA to its receptors LPA1-6 activates multiple cellular processes such as migration, proliferation and survival. The production of LPA and activation of LPA receptor signaling pathways in the events of physiology and pathophysiology have attracted the interest of researchers. Results from studies using transgenic and gene knockout animals with alterations of ATX and LPA receptors genes, have revealed the roles of LPA signaling pathways in metabolic active tissues and organs. The present review was aimed to summarize recent progresses in the studies of extracellular and intracellular LPA production pathways. This includes the functional, structural and biochemical properties of ATX and LPA receptors. The potential roles of LPA production and LPA receptor signaling pathways in obesity, insulin resistance and liver fibrosis are also discussed.

关键词： Autotaxin Lysophosphatidic acid receptors Obesity Lysophosphatidic acid Insulin resistance Liver fibrosis

BAYESIAN DEMONSTRATION TEST METHOD WITH MIXED BETA DISTRIBUTION

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Chinese Journal of Mechanical Engineering 2008年第3期21卷 116-119页

作者： MING Zhimao TAO Junyong chen xun ZHANG Yun＇an College of Mechatronics Engineering and Automation N~onal University of Defense Technology Changsha 410073 China Reliability Testing Laboratory National University of Defense Technology Changsha 410073 China Department of Mechanical Engineering University of Maryland MD 20742 USA Colloge of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China

A complex mechatronics system Bayesian plan of demonstration test is studied based on the mixed beta distribution. During product design and improvement various information is appropriately considered by introducing inheritance factor, moreover, the inheritance factor is thought as a random variable, and the Bayesian decision of the qualification test plan is obtained, and the correctness of a Bayesian model presented is verified. The results show that the quantity of the test is too conservative according to classical methods under small binomial samples. Although traditional Bayesian analysis can consider test information of related or similar products, it ignores differences between such products. The method has solved the above problem, furthermore, considering the requirement in many practical projects, the differences among this method, the classical method and Bayesian with beta distribution are compared according to the plan of reliability acceptance test.

关键词： Reliability qualification test Inheritance factor Bayesian analysis Binomial distribution Maximum posterior risk

Running coupling constant at finite chemical potential and magnetic field from holography

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Chinese Physics C 2022年第7期46卷 8-14页

作者： xun chen Lin Zhang Defu Hou School of Nuclear Science and Technology University of South China Hengyang 421001China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Central China Normal University Wuhan 430079China

According to gauge/gravity duality,we use an Einstein-Maxwell-dilaton(EMD)model to study the running coupling constant at finite chemical potential and magnetic ***,we calculate the effect of temperature on the running coupling constant and find the results are qualitatively consistent with lattice guage ***,we calculate the effect of chemical potential and magnetic field on running *** is found that the chemical potential and magnetic field both suppress the running coupling ***,the effect of the magnetic field is slightly larger than that of chemical potential for a fixed *** with the confinement phase,the magnetic field has a large influence on the running coupling in the deconfinement phase.

关键词： holographic QCD magnetic field running coupling