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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 {3. {3. 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 3. 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

Singularity of Some Software Reliability Models and Parameter Estimation Method

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wuhan university Journal of Natural {2. 2000年第1期5卷 35-40页

作者： XU Ren-zuo ZHOU Rui YANG Xiao-qing (state key {2. of Software {3.,{3., wuhan 43.072, China) wuhan Univ Wuhan China

According to the principle, “The failure data is the basis of software reliability analysis”, we built a software reliability expert system (SRES) by adopting the artificial intelligence technology. By reasoning out the conclusion from the fitting results of failure data of a software project, the SRES can recommend users “the most suitable model” as a software reliability measurement model. We believe that the SRES can overcome the inconsistency in applications of software reliability models well. We report investigation results of singularity and parameter estimation methods of experimental models in SRES.

关键词： software reliability measurement models software reliability expert system singularity parameter estimation method path following method maximum likelihood ML-fitting algorithm

water Security Problem in North China: Research and Perspective

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Pedosphere 2005年第5期15卷 563-575页

作者： XIA Jun LIU Meng-Yu JIA Shao-Feng key laboratory of {2. Cycle ＆Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） state key {2. of {3. {3. ＆ hydropower engineering sciences Wuhan University Wuhan 430072（China） Center for Agricultural resources Research Institute of Genetic and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 （China）

This paper addresses the emergence of water security problems in North China with the aim of highlighting key water{3. management and water security issues for the long-term development of North China. Three key problemsrelated to water {3. and security issues in North China in the 2.st century are addressed, namely 1) the watercycle under environmental change, 2. agricultural water saving, and 3. water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese Academy of {13.(CAS) is discussed and suggestions on research and development of water {3. science in North China are *** to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth China farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 2.%-3.%.Furthermore, preventing water pollution is the most essential step to ensure North China’s water security.

关键词： environmental change North China water cycle water resources water security

Gradient Gene Algorithm: a Fast Optimization Method to MST Problem

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wuhan university Journal of Natural {2. 2001年第Z1期6卷 535-540页

作者： Zhang Jin bo, Xu Jing wen, Li Yuan xiang state key {2. of Software {3.,{3., wuhan 43.072, China state key {2. of Software {3. Wuhan University Wuhan China

The extension of Minimum Spanning Tree(MST) problem is an NP hard problem which does not exit a polynomial time algorithm. In this paper, a fast optimization method on MST problem——the Gradient Gene Algorithm is introduced. Compared with other evolutionary algorithms on MST problem, it is more advanced: firstly, very simple and easy to realize; then, efficient and accurate; finally general on other combination optimization problems.

关键词： combination optimization minimum spanning tree problem extension of minimum spanning tree problem gradient gene algorithm

Image City sharing platform and its typical applications

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Science China(Information sciences) 2011年第8期54卷 1738-1746页

作者： SHAO ZhenFeng & Li DeRen state key {2. for Information {3. in Surveying,Mapping and Remote Sensing,{3. university,{3. 43.079,China state key {2. for Information {3. in Surveying Mapping and Remote Sensing Wuhan University

In this paper,the trend of urban spatial information sharing service from the electronic map to image is analyzed and its sharing framework based on service-oriented architecture is ***,the service implementation,feedback data service procedure and its processing service model are explored. Based on the software with independent intellectual property rights,image city of Taizhou is developed as an example to realize various image data and processing servicesLastly,the bright future prospects of image city are described.

关键词： Image City service-oriented architecture image data service function service model service

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

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Journal of Iron and Steel Research International 2012年第10期19卷 13-19页

作者： XIAO Xiao-feng1,2. YE Sheng-ping2. YIN Wei-xin3. XUE Qiong4 (1. School of Mechanical engineering and Automation, {3. Textile {2., {3. 43.073. Hubei, China 2. state key laboratory of Material Processing and Die and Mould Technology, Huazhong {2. of Science and Technology, {3. 43.074, Hubei, China 3. {3. Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd, {3. 43.073. Hubei, China 4. College of Science, wuhan university of Technology, {3. 43.079, Hubei, China) School of Mechanical engineering and Automation Wuhan Textile University Wuhan Hubei China state key {2. of Material Processing and Die and Mould Technology Huazhong University of Science and Technology Wuhan Hubei China wuhan Zhike Abrasive-Resistant Material Science and Technology Development Co Ltd Wuhan Hubei China College of Science Wuhan University of Technology Wuhan Hubei China

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2.and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.

关键词： composite liner bimetal liquid-liquid compound composite interface lost foam casting high Cr white cast iron

An ideal interval method of multi-objective decision-making for comprehensive assessment of water resources renewability

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Science China(Technological sciences) 2004年第z1期47卷 42-50页

作者： YANG Xiaohua1, YANG Zhifeng1,2. SHEN Zhenyao1 & LI Jianqiang3.1. School of Environment, state key {2. of water Environment Simulation, Beijing Normal Univer- sity, Beijing 100875, China 2. School of Environment, key {2. for water and Sediment sciences of Ministry of Education, Beijing Normal university, Beijing 100875, China 3. water resources and {13. Planning and Design General Institute, MWR, Beijing 100011, China School of Environment State Key Laboratory of Water Environment Simulation Beijing Normal University Beijing 100875 China key laboratory for {2. and Sediment {3. Beijing Normal University Ministry of Education Beijing 100875 China water resources and {2. Planning and Design General Institute MWR Beijing 100011 China

In order to estimate water resources renewability scientifically, an Ideal Interval Method of Multiple Objective Decision-Making (IIMMODM) is presented. This method is developed through improving an ideal point method of multiple objective decision-making. The ideal interval is obtained with assessment standard instead of ideal points. The weights are decided by using the basic point and gray code accelerating genetic algorithm. This method has synthesized the expert’s suggestion and avoided giving a mark for the objective again. It could solve the complicated problem of compatible or incompatible multi-objective assessment. The principle of IIMMODM is presented in this paper. It is used to assess the water resources renewability for nine administrative divisions in the Yellow River basin. The result shows that the water resources renewability in the Yellow River basin is very low. Compared with the gray associate analysis method, fuzzy synthesis method and genetic projection pursuit method, the IIMMODM is easier to use. Compared with the ideal point method of multiple objective decision-making, the IIMMODM has good robustness, which is applicable to the comprehensive assessments of water resources.

关键词： water resources renewability, comprehensive assessment, multiple objective decision-making,ideal interval, Yellow River basin.

过烧氧化镁的水化及其对混凝土自生体积变形的影响

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水力发电学报 2004年第4期23卷 45-49页

作者：方坤河武汉大学水资源与水电工程科学国家重点实验室武汉430072

本文介绍了MgO的生成条件对其晶格常数、内比表面积和水化速度的影响 ;说明随着煅烧温度的提高及煅烧时间的延长 ,MgO的晶格变小、内比表面积降低 ,MgO的水化速度下降、水化的固相体积增大。文章论述了水泥中MgO的水化行为及影响外掺Mg... 详细信息

本文介绍了MgO的生成条件对其晶格常数、内比表面积和水化速度的影响 ;说明随着煅烧温度的提高及煅烧时间的延长 ,MgO的晶格变小、内比表面积降低 ,MgO的水化速度下降、水化的固相体积增大。文章论述了水泥中MgO的水化行为及影响外掺MgO混凝土的自生体积变形的因素。

关键词：氧化镁混凝土自生体积变形综述水化影响因素

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 {3. in Surveying,Mapping and Remote Sensing,{3. university,{3. 43.072,China state key {2. of Information {3. 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