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The entropy of system Decreases with the Deflection from the Equiprobability Distribution

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systems Science and systems Engineering 2000年第4期10卷 496-502页

作者： TIAN Bao\|guo,\ GU Ke,\ JIANG Lu Beijing Normal University, Beijing 100875, China

The article gives the definition of the deflection from the equiprobability distribution(DFED), and proves that the entropy decreases with the increasing of DFED.

关键词： information entropy system entropy deflection from the equiprobability distributio0

A survey on the network models applied in the industrial network optimization

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Science China(Information Sciences) 2024年第2期67卷 85-103页

作者： Chao DONG Xiaoxiong XIONG Qiulin XUE Zhengzhen ZHANG Kai NIU Ping ZHANG Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications Smart City College Beijing Union University

Network architecture design is critical for optimizing industrial networks. Network architectures can be classified into small-scale networks and large-scale networks based on scale. Graph theory is an efficient mathematical tool for network topology modeling. For small-scale networks, their structure often has regular topology. For large-scale ones, the current body of work mainly focuses on random characteristics of network nodes and edges. Recently, widely used models include random networks, small-world networks,and scale-free networks. In this study, starting from the scale of the network, network modeling methods based on graph theory as well as their industrial applications, are summarized and analyzed. Moreover, a novel network performance metric, called system entropy, is proposed. From the perspective of mathematical properties, an analysis of its non-negativity and concavity is performed. The advantage of system entropy is that it can cover the existing regular networks, random networks, small-world networks, and scale-free networks, and has strong generality. The simulation results reveal that this proposed metric can achieve the comparison of various industrial networks under different models.

关键词： industrial network small-scale network large-scale network graph theory system entropy

STATUS AND DYNAMIC CHANGE OF REGIONAL MAN- LAND system IN VIEW OF MICRO-LEVEL QUANTITATIVE ASPECT -Case Study of Gongyi City of Henan Province

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Chinese Geographical Science 2006年第1期16卷 9-17页

作者： QIAO Jia-jun LI Xiao-jian KONG Yun-feng Key Research Institute of Yellow River Civilizatin and Sustainable Development Henan University Kaifeng 475001 P.R.China College of Environment and Planning Henan University Kaifeng 475001 P.R.China

A micro-level analysis on man-land system is important in understanding the content of human geography in rural areas, particularly in the different regions. This paper is based on a survey undertaken in the three villages of Wugou Village, Hutuo Village, and Xiaonan Village of Gongyi City, ltenan Province in April 2003. The survey covers three types of economic and social activities from 214 households. Data collected include 120 attributes for each household. By using theories from the relevant disciplines such as geography, mathcmatics, physics, ecology, and system sciences, this paper develops a framework employing the concept of system entropy in the status function of the man-land system. In this framework, the entropy change is used to show the evolution of the system, and the entropy flow to express the flow among the spatial parts of the system. Following the framework, and using a large set of household data from surveys, the paper makes a quantitative analysis of the village-level man-land system from a micro-perspective. After a theoretical investigation, the corresponding strategies in the paper are then put forward in order to adjust the unbalanced trend of the village man-land system from both perspectives of small-area and individual actors.

关键词： man-land system village-level region system entropy

Jiuzhaigou Ecotourism Areal system:Temporal Evolution of Entropic Change

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Wuhan University Journal of Natural Sciences 2008年第3期13卷 303-308页

作者： SHEN Xingju SU Chunjiang LI Weiji Institute of Mountain Hazards and Environment ChineseAcademy of Sciences Chengdu 610041 Sichuan China College of Tourism and Historical Culture SouthwestUniversity for Nationalities Chengdu 610041 Sichuan China

The temporal evolution of entropy of Jiuzhaigou ecotourism areal system has been quantitatively analyzed by using equation of system entropy V = k In M - k In C. The computed entropy for Jiuzhaigou ecotourism areal system for 20 years indicates a negative value during 1986-1996, which implies that the system had remained a healthy state during this period. The system entropy value, however, showed a constant increase since 1996 until it turned to be positive in 2000 when the system became chaotic. After 2000 the entropy value declined until 2003 when it escalated once again. By analyzing the causes and process of entropy change of the system, it is argued that fluctuation of entropy value is due to the overloading of tourist service capacity by tourism activities. It is desired to curb the flow of tourist volume and reinforce conservation efforts as well as, so that an ideal balance between conservation and development could be maintained.

关键词： Jiuzhaigou system entropy ecotourism chaotic degree evolution