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Comprehensive health condition assessment on partial sewers in a southern Chinese city based on fuzzy mathematic

Lili GAN, Jiane ZUO, Yajiao WANG, Thong Soon LOW, Kaijun WANG

《环境科学与工程前沿（英文）》 2014年第8卷第1期页码 144-150 doi: 10.1007/s11783-013-0554-8

摘要： A self-developed sewer health assessment system using the fuzzy comprehensive evaluation and analytical hierarchy process was applied to give a comprehensive health condition evaluation on part of the local sewers in a southern Chinese city based on the sewer video data collected by a sewer inspection closed circuit television (CCTV) robot. Aside from the overall condition evaluation, the structure, function, and stability status of the sewer were also analyzed using the method. A comprehensive index was proposed to give the overall health condition of pipes with different defects, and , , and were used to quantify the defects affecting the tightness, stability, and function of the pipe, respectively. Results show that 48% of the inspected pipes were in good condition (0< <0.25), and about 33% of the sewer pipes analyzed were categorized to be at severe or urgent condition levels ( >0.5), although most of the pipes were installed only within five years. Frequent sedimentation affects the function of the sewer, and deformation and joint damage affect the structure of the sewer.

关键词： sewer health condition assessment analytical hierarchy process fuzzy comprehensive evaluation fuzzy mathematic method

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小型农业生态工程——庭院经济发展的数学模型

卞有生

《中国工程科学》 2000年第2卷第5期页码 60-65

摘要：

农业生态工程数学模型的任务在于提供对于系统现状及其功能、结构的认识，并用于预测系统即将发生的行为，进一步外加某种措施，对系统实施控制，以求达到它的最优化。文章通过理论研究和实践试验，建立了小型农业生态工程的数学模型。并以北京市大兴县留民营村一家农户为例，介绍小型农业生态工程的数学模型，及其在指导实际建设中的应用。

关键词：庭院经济数学模型农业生态工程

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中型农业生态工程的数学模型

卞有生,刘来福,徐汝梅

《中国工程科学》 2001年第3卷第11期页码 39-44

摘要：

章以北京大兴县留民营村为例，建立了中型（村庄级）农业生态工程的数学模型，该模型为分室模型，由8个分室组成，文中给出了各个分室的状态变量及控制变量，建立了各分室的数学模型，并应用该数学模型指导了留民营的实际生产建设，取得了良好结果。

关键词：农业生态工程数学模型状态变量控制变量

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Shock wave of vapor-liquid two-phase flow

ZHAO Liangju, GAO Hong, TANG Jingwen, YUAN Yuexiang, WANG Fei

《能源前沿（英文）》 2008年第2卷第3期页码 344-347 doi: 10.1007/s11708-008-0065-7

摘要： The shock wave of vapor-liquid two-phase flow in a pressure-gain steam injector is studied by building a mathematic model and making calculations. The results show that after the shock, the vapor is nearly completely condensed. The upstream Mach number and the volume ratio of vapor have a great effect on the shock. The pressure and Mach number of two-phase shock conform to the shock of ideal gas. The analysis of available energy shows that the shock is an irreversible process with entropy increase.

关键词： available mathematic conform vapor-liquid two-phase analysis

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考虑多孔电极内气液分布的数学模型

徐献芝,朱梅,杨基明

《中国工程科学》 2005年第7卷第8期页码 36-40

摘要：

给出了多孔电极内不同气液分布形状的溶液欧姆定律；在单孔电极模型基础上定义了电化学反应的有效三相分界线长度概念，并给出了对应的计算方法；建立了基于多孔介质气液分布理论的一维电流和过电位数学模型，用数值迭代方法计算了沿电极面法线方向上的电流和过电位分布，分析了气体饱和度分布和有效三相分界线长度对它们的影响。

关键词：多孔介质过电位单孔电极模型三相界面数学模型