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Fuzzy entropy image segmentation based on particle swarm optimization

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Progress in Natural Science:Materials International 2008年第9期18卷 1167-1171页

作者： Linyi Li a, Deren Li b, a School of Remote Sensing and Information engineering, wuhan university, {2. 430079, china b state key laboratory of Information engineering in Surveying, Mapping and Remote Sensing, wuhan university, {2. 430079, china School of Remote Sensing and Information engineering Wuhan University Wuhan 430079 China state key {2. of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China

Particle swarm optimization is a stochastic global optimization algorithm that is based on swarm *** of its excellent performance, particle swarm optimization is introduced into fuzzy entropy image segmentation to select the optimal fuzzy parameter combination and fuzzy threshold *** this study, the particles in the swarm are constructed and the swarm search strategy is proposed to meet the needs of the segmentation *** fuzzy entropy image segmentation based on particle swarm opti-mization is implemented and the proposed method obtains satisfactory results in the segmentation *** with the exhaustive search method, particle swarm optimization can give the same optimal fuzzy parameter combination and fuzzy threshold while needing less search time in the segmentation experiments and also has good search stability in the repeated ***, fuzzy entropy image segmentation based on particle swarm optimization is an eficient and promising segmentation method.

关键词： Image segmentation Fuzzy entropy Particle swarm optimization Fuzzy parameter combinations Fuzzy threshold

A coupled elasto-plastic-damage mechanical model for marble

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Science china(Technological sciences) 2011年第S1期54卷 228-234页

作者： ZHOU Hui 1,ZHANG Kai 2.& FENG XiaTing 1 1 state key {2. of Geomechanics and Geotechnical engineering,Institute of Rock and Soil Mechanics,Chinese Academy of sciences,wuhan 430071,china 2.state key {2. for Geomechanics and Deep Underground engineering,china {12. of Mining&Technology,Xuzhou 2.1008,china state key {2. of Geomechanics and Geotechnical engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan China state key {2. for Geomechanics and Deep Underground engineering China University of Mining & Technology Xuzhou China

A profound understanding of the mechanical behaviors of marble is very important for the design and construction of deep diversion tunnels in Jinping II hydropower *** this paper,a coupled elasto-plastic-damage mechanical model is presented for Jinping ***,the experimental investigations on Jinping marble are ***,based on the framework of continuum damage and plastic theories,a general mechanical model is proposed to predict the mechanical responses of Jinping *** proposed model is used to simulate the triaxial compressive tests,and there is a general good agreement between experimental data and numerical predictions in a qualitative *** proposed model is able to capture the main features of Jinping marble observed in experiments,such as progressive yielding process,damage induced by plastic distortion,dilation,elastic degradation and stress sensitivity.

关键词： mechanical model damage elasto-plastic coupling marble

Multi-source geospatial information integration and sharing in Virtual Globes

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Science china(Technological sciences) 2010年第S1期53卷 1-6页

作者： GONG JianYa,XIANG LongGang,CHEN Jing & YUE Peng state key {2. of Information engineering in Surveying,Mapping and Remote Sensing,wuhan university,wuhan 43.072,china state key {2. of Information engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China

Massive volumes of global geospatial information are being collected by newly designed acquisition devices and generated by various geospatial *** poses a critical challenge to efficiently organize and effectively integrate global multi-source geospatial *** paper introduces a global seamless data model for the organization of huge multi-source,multi-resolution and multi-temporal geospatial *** on this data model,the management of the global multi-resolution pyramid is discussed in *** integrate geospatial data and processing functions from various GIS systems,a service-oriented framework is presented through the technology of Virtual ***,a Virtual Globe system,GeoGlobe,is developed and illustrated.

关键词： Virtual Globe geospatial information multi-resolution pyramid Web service GeoGlobe

Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2. TAN Zhi-xiang1, 2. DENG Ka-zhong1, 2.1. key laboratory for Land Environment and Disaster Monitoring of {2. Bureau of Surveying and Mapping, china university of Mining and Technology, Xuzhou 2.1116, china 2. Jiangsu key laboratory of resources and Environmental Information engineering, china university of Mining and Technology, Xuzhou 2.1116, china key laboratory for Land Environment and Disaster Monitoring of {2. Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu key laboratory of {2. and Environmental Information engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2.] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of Xuzhou, china was shown as application example. engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

Stress-strain analysis of Aikou rockfill dam with asphalt-concrete core

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Journal of Rock Mechanics and Geotechnical engineering 2011年第2期3卷 186-192页

作者： Chaoyang Fang, Zhenzhen Liu state key {2. of water resources and hydropower engineering sciences, wuhan university, wuhan, 43.072, china state key {2. of water resources and hydropower engineering sciences Wuhan University Wuhan 430072 China

Aikou rockfill dam with asphalt-concrete core is situated in a karst area in Chongqing City, china. In order to study the operative conditions of the rockfill dam, especially those of the asphalt-concrete core, the Duncan model is adopted to compute the stress and strain of both the rockfill dam and the asphalt-concrete core after karst grouting and other treatments. The results indicate that the complicated stress and deformation of both the dam body and the core are within reasonable ranges. It is shown that structure design and foundation treatment of the dam are feasible and can be used as a reference for other similar projects.

关键词： asphalt-concrete core rockfill dam Aikou reservoir stress and deformation

Cell Evolutionary Algorithm: a New Optimization Method on Ground-state Energy of the Atomic

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wuhan university Journal of Natural {2. 2000年第4期5卷 425-430页

作者： Liu Lian-jun, Xu Jing-wen, Mao You-dong, Li Yuan-xiang Department of Physics, wuhan university, wuhan 43.072,{2. state key laboratory of Software engineering,wuhan university, wuhan 43.072, china Department of Physics Wuhan University Wuhan China state key {2. of Software engineering Wuhan University Wuhan China

The purpose of this paper is to present a new general approach to solve ground-state energies of the double-electron systems in a uniform magnetic field, in which the basic element of evolution is the set in the solution space, rather than the point. The paper defines the Cell Evolutionary Algorithm, which implements such a view of the evolution mechanism. First, the optimal set in which the optimal solution may be obtained. Then this approach applies the embedded search method to get the optimal solution. We tested this approach on the atomic structure, and the results show that it can improve not only the efficiency but also the accuracy of the calculations as it relates to this specific problem.

关键词： key words double electron systems ground state energy variational principle cell evolutionary algorithm evolutionary algorithm

New Refinement Relations of Z Specifications for Multiple Viewpoints Oriented Requirements Method

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wuhan university Journal of Natural {2. 2001年第Z1期6卷 304-312页

作者： He Yan xiang, Song Qiang, Huang Qian School of Computer, state key {2. of Software engineering wuhan university, wuhan 43.072, china School of Computer State Key Laboratory of Software Engineering Wuhan University Wuhan China

In this paper we develop several new refinement relations of Z for multiple viewpoints oriented requirements method (MVORM). The original motivation is that we found the standard Z refinement relation is not adequate or correct when considering specifications that have temporal relationships of operations. The concept of temporal state variables is introduced into Z. Then new implementation relations are defined and new refinement relations are deduced, mainly for temporal state variables to process temporal relationships of operations. We use state transition systems to abstract the temporal state transitions. A simple example is used to show the procedures of MVORM. Finally some directions of further work are forwarded.

关键词： temporal state variable formal description language state transition system implementation relation refinement relation multiple viewpoints oriented requirements method

Stability Analysis on Automatic Control Methods of Open Canal

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wuhan university Journal of Natural {2. 2011年第4期16卷 325-331页

作者： FENG Xiaobo WANG Kang state key {2. of water resources and hydropower engineering Science/wuhan university Wuhan 430072 Hubei China

The relationship between the automatic control method and the stability of the open canal is studied by means of numerical simulation of unsteady flow in an open canal under different methods of control. It is found the Proportional-Proportional plus Reset （P＋PR） control is more reliable than the Linear Quadratic Regulator （LQR） control. Moreover, for the P＋PR control, the hydraulic response of the constant volume method of operation is better than that of the constant downstream depth method in the type of centrally controlled canal. Therefore, an appropriate flow change rate should be chosen instead of shortening the pool length to reach an acceptable drawdown rate. For the canal with a bottom width of 40 m, side slope of 3, Manning n of 0.015, bottom slope of 0.000 04, and design flow of 600 m3/s, the pool length of more than 30 km can provide acceptable drawdown rates of 0.2.m/h when a proper flow change rate is chosen.

关键词： open canal automatic control Chinese South-to- North water Diversion Project unsteady flow

Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay

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Science china(Technological sciences) 2010年第4期53卷 1114-1125页

作者： YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2.& XIAO ShangBin1,3 1 College of Civil & Hydroelectric engineering,china Three Gorges {2.,Yichang 443002.china 2.School of water resources & hydropower engineering,wuhan {2.,wuhan 43.072,china 3 Institute of Earth Environment,Chinese Academy of sciences,Xi’an 710075,china College of Civil & Hydroelectric engineering China Three Gorges University Yichang China School of water resources & {2. engineering Wuhan University Wuhan China Institute of Earth Environment Chinese Academy of Sciences Xi’an China

The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,*** hydrodynamic parameters and water quality parameters(*** velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 *** water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different *** water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding ***,the water stability index in the mainstream remained small but it was lowered in the *** main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding *** grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the ***,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

关键词： impounding density current eutrophication the Xiangxi Bay the Three Gorges Reservoir