关于非线性浅水波理论中的孤立波解

本文在[1]的基础上,详尽地得到了Boussinesq方程和KdV方程的孤立波解,并对波高和波形进行了细致的分析。为了更好地比较,本文还给出了高阶摄动的孤立波解。     

36 m 高砖砌水塔定向折叠爆破拆除

介绍了复杂环境中砖砌高大水塔的定向折叠爆破拆除.根据周围的环境情况,在施工中采用了开定向窗、挖定位坑等技术措施,确保爆破成功,达到了设计效果.     

Application of Fuzzy Control into a New Kind of Sea Water Still

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离子静电水处理技术在循环冷却水中的应用

简要介绍了离子静电水处理技术杀菌、灭藻、防垢阻垢的机理，及在循环冷却水系统中的应用情况。     

Open‐cycle OTEC systems with freshwater product: Effects of noncondensable gases on performance of condenser

An open‐cycle ocean thermal energy conversion (OC‐OTEC) system is one of the energy conversion methods used to generate electricity from ocean thermal energy. For the OC‐OTEC system, steam evaporated from the surface seawater due to flash evaporation drives the turbine. At that time, dissolved gas such as air is introduced into the low‐pressure system (OC‐OTEC system) as the noncondensable gas, which degrades the performance of condensation heat transfer. In this paper, a small‐scale OC‐OTEC experimental unit experimentally investigates the effect of noncondensable gas on the heat transfer performance in a condenser. The experimental results are discussed in comparison with theoretical estimation by the Sparrow–in method. It is shown that the condensation is occupied by heat and mass transfer near a condensation surface and that the condensation efficiency is affected by exhaust quantity of noncondensable gas at a relatively high concentration ratio of condensable gas. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 29–35, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20179     

Water quality assessment of a recently refilled reservoir: The case of Bütgenbach Reservoir, Belgium

Bütgenbach Reservoir is situated in the High Ardennes plateau in eastern Belgium (50°25′N; 6°13′E). It is used principally for flood control and for production of hydroelectric energy. It has been subjected to a previous series of studies because of its eutrophication problems and their impacts on the local economy. Bütgenbach Reservoir was emptied during spring 2004 for dam restoration, being refilled in mid‐September of the same year. Selected physicochemical and biological parameters (temperature, dissolved oxygen, pH, inorganic and organic nutrients, chlorophyll‐a) were measured fortnightly during the lake's productive season (mid‐April to mid‐October 2005) at three sampling sites throughout the water column. The water quality conditions after refilling of the lake were compared to previous studies accomplished at the same sampling sites (prior to emptying the lake). The actual trophic status was mesotrophic to eutrophic, based on the combination of total phosphorous and chlorophyll‐a concentrations, as well as water transparency. Bütgenbach Reservoir generally exhibits good water quality, based on the French water quality system SEQ‐eau. A longitudinal decrease in water quality was observed from upstream to downstream, because mainly of the differences in lake bottom morphology and water residence time, and their impacts on nutrient distribution in the lake.     

Effect of Channel Changes in the St. Clair River During the Present Century

Periodic man-made changes in the outlet of Lake Huron through the St. Clair River date back to the middle of the last century. These artificial channel changes have been well documented during the present century. They consist of dredging for commercial gravel removal in the upper river during 1908–25 and uncompensated navigation improvements for the 7.6-m (25-ft) and 8.2-m (27-ft) projects completed in 1933 and 1962, respectively. The total effect of these changes on the levels of Lakes Michigan and Huron (hydraulically one lake) and on the upper St. Clair River profile was determined with dynamic flow models. The ultimate effect of the above dredging was a permanent lowering of the Lake Michigan-Huron levels 0.27 m (0.89 ft), which represents a tremendous loss of freshwater resource [32 km³ (7.7 mi³)].     

辽宁省节水工作存在问题及对策

辽宁省是水资源严重短缺的省份之一，水资源不足已成为制约全省经济社会可持续发展的瓶颈。通过对全省大型取用水户的调查分析，找出了辽宁省节水工作中存在的问题，提出了节约用水工作的对策和建议。     

底水油藏射孔优化设计

为了优化底水油藏的生产参数，研究了不同产量时射孔长度的优化方法。采用球面流和径向流相结合的模型推导了临界产量和无水采油量的计算公式，分别以临界产量和无水采油量为标准，对胜利油田桩西区块底水油藏上6口油井的射孔长度进行了优化设计，优化结果表明，对于底水油藏应首先按照临界产量对射孔长度进行优化设计，如果得到的最大临界产量不符合实际生产的要求，就应按照无水采油量进行射孔优化设计。研究表明，当油井产量超过临界产量后，以临界产量为标准得到的优化射孔长度会减小油井的无水采油量。