Water Supply in Medieval Middle Eastern Cities: The Case of Cairo

In spite of its location on the Nile bank, medieval Cairo suffered from serious problems of water supply because of its topography and the Nile regime that necessitated water storing. Direct canalization was not adopted to channel the Nile to inhabited quarters, either on the riverside or inland because of the dangers entailed in an uncontrolled water race during the Nile inundation. The Nile water was safely conveyed inland in canals, dammed by dikes at their mouths on the Nile before the inundation, and opened when the water level reached sixteen arms. Aqueducts and conduits carried the water from the canals to inland open reservoirs, or artificial lakes, around all of which grew residential quarters. The lake waters were transferred to cisterns and above ground tanks that were used as closed water reservoirs before distribution in the residential quarters of Cairo. Scattered in central sites within the quarters, there were the big wells and basins that received water from outside the quarter for distribution to the wells located near the houses, baths and mosque courtyards. The quarters' wells and tanks usually had a common water source and the houses' wells were interconnected by a labyrinth of underground conduits. Residences of the elite and bourgeoisie were equipped with water facilities as befitted their status. The upper middle class often rented qā‘as, exclusive residential units located on the ground floor, equipped with water systems. The lower socio-economic classes, which constituted the majority of the population, lived in standard units in residential complexes that were not equipped with running water but only with water jars. The general public regularly visited public baths for both personal hygiene and leisure, consumed commercially prepared food in the market and sent their clothes for laundering and pressing in the market.     

也谈小型水库除险加固工程的建设与管理

文章从莒县目前状况出发,结合工程施工管理实际,探讨了小型水库除险加固工程施工管理的路子,为今后水库除险加固奠定基础。     

基于奇异值分解的电网潮流转移模式研究

针对电网潮流转移场景下支路传输功率和电网节点注入功率之间的关联作用关系,提出了一种分析节点注入功率模式的方法。根据支路传输功率和电网节点注入功率之间的关联作用关系矩阵,利用矩阵奇异值分解,将节点注入功率分解为各种模式;在此基础上,进一步分析节点注入功率的各种模式的表现形式并进行算例分析。算例分析初步表明,在节点注入功率模式的各种表现形式中,比较常见的是以部分奇异值为主导的作用模式,在实际分析和处理中,把握这样的主导模式,将有利于进一步的分析和预防潮流转移引起的不利后果。     

基于PIDE串级控制在THJ-2系统中应用

以THJ-2型高级过程控制系统作为研究对象,将串级控制理论应用到模拟的工业现场的对象中去。应用ROCKWELL硬件,设计信号采集和控制平台,通过PIDE功能块进行回路自整定,获得控制器PID参数,实现水箱液位的串级控制。     

水库型饮用水水源地非点源污染控制技术方法

为了改善水库型饮用水水源地普遍存在的富营养化和水质达不到功能区划要求的现状，以合肥市为例，在现状调查的基础上，应用功能性模型中国土壤流失预报方程并适当地进行修正，对非点源污染负荷和水环境容量进行了定量分析，得出了非点源污染的主要来源和污染规律，并据此提出了水库型饮用水水源地非点源污染的控制技术方法．     

澜沧江梯级开发的水政治:现状、挑战与对策

20世纪90年代以来,澜沧江干流梯级开发的跨境影响一直是国际社会激烈争论的焦点。随着流域内水能资源开发、市场需求和环境保护一体化地形成和发展,研究与之有关的水政治,有利于共享水资源开发与协调管理。在对国际上关于澜沧江大坝水政治言论和观点综述基础上,判识了其实质和特征;从认识基础差异和管理机制不完善、外部势力介入、民间外交薄弱、全球化和气候变化方面系统分析了中国在水政治冲突与合作上的挑战;从建立互信机制、实施流域整体开发、构建合作机构、多方参与和利益补偿、科技与信息交流等方面提出中国的应对措施,为澜沧江开发与管理过程中,协调上下游关系、维护区域安全与稳定以及顺利推进区域合作等提供科学依据。     

雄安新区地热资源与开发利用研究

雄安新区地热资源丰富且比较容易开采,在生态文明建设中可发挥重要作用。雄安新区浅层(200米)地热能宜于开采;深层(200—3000米)地热能中的砂岩储层和碳酸盐岩储层热量大,宜于开采;超深层(3000米)地热能也具有开采潜力。雄安新区的雄县在利用大型岩溶热储开展规模化供暖方面,单一项目已实现世界最大(450万平方米)供暖能力。文章认为,雄安新区应该加大地热资源勘查力度,重点是超深层碳酸盐岩热储;在利用上,要做到因地制宜,深、浅资源合理配置,还要重视环境保护,协调好与其他资源利用的关系;同时,要发展地热储能技术,形成以地热为主体,多能互补的"地热+"的清洁能源利用新格局。     

蒙江流域水文特性及水能资源梯级开发简介

在简要分析了蒙江流域水文特性的基础上,对蒙江流域水能资源的开发现状和梯级开发方案作了简要介绍.并对梯级开发方案中最大的在建电站--双河口水电站进行了较详细的介绍.