Artificial neural network based predictive method for flood disaster

Most of flood disaster predictions belong to ill-structured problems, while artificial neural network (ANN) has several characteristics that are suitable for solving them. In this paper, a neural network based predictive method for flood disaster problem is proposed in which the neural network model and its basic designing principles are described, and an example of flood disaster area in China from 1949 to 1994 is used for demonstration.     

三峡水利枢纽的设计洪水

在进行了大量分析研究后，认为三峡水系列采用Ｐ－Ⅲ型理论分布曲线进行拟合是合适的，采用１９５４，１９８２，１９８１年实测洪水作为设计洪水典型是可行的，安全的；采用的入库设计能反映三水库建成后的实际情况；各种时段洪量的期望概率，十分接近或销低于设计频率，能满足工程指定的设计标准；计算的可能最大洪水及校核洪炎为１１７５００－１２７０００ｍ＾３／ｓ，７天洪量６０７－６５２亿ｍ＾３１５天洪量可能最大洪水为１     

河道洪水实时预报模型及在寸滩—螺山河段的应用

采用水力学和水文学相结合的方法，根据河道非恒定流的圣维南方程组，建立了河道洪水相应涨至预报模型和扩散波洪水预报模型，既可预报流量，又可预报水位。在模型的实时校正技术中，采用了具有时变遗忘因子的递推最小二乘实时校正算法，提高了参数实时跟踪能力和辨识精度。相应涨差实时预报模型和扩散波实时预报模型在寸滩－螺山河段上的应用均获得较好的效果。     

含流砂地基防洪堤桩基施工

分析了广西藤县城区河西防洪堤的工程地质情况,提出了采用人工和机械挖孔桩方案对大堤含流沙地基进行基础加固。论述了桩基施工的工艺流程和技术措施,总结了在含有流沙的地基进行防洪堤桩基施工各环节中,确保工程质量和施工安全的技术方法。     

应急通信演练规程探讨

就应急通信演练规程中应注意的问题作了简要阐述和总结，并对应急通信机车运行、传输实施、基站开通提出了一些建议。     

Remote flood monitoring system based on plastic optical fibres and wireless motes

This paper summarises an effort in the development of a remote flood monitoring system based on plastic optical fibre (POF) sensors and a wireless mote network. The wireless mote, comprising of a network of MICA2DOT™ units, was used as a platform to monitor and record the signal from the POF sensors and transmit this information to a base station wirelessly. A prototype of the integrated wireless POF sensor unit has been constructed, rendering it possible to deploy the autonomous unit remotely at multiple monitoring points as required. A flood monitoring simulation was carried out in a 24 m × 10 m × 0.9 m wave basin where four of these wireless optical fibre mote sensors were used to detect the rising water level in the basin. The novelty of the work lies in the successful integration of the wireless platform to a POF-based liquid level sensor and the subsequent demonstration of the prototype of the system for the purposes of flood monitoring applications.The sensing principle of the POF sensor developed here is well-known and is based on the loss of total internal reflection of the optical signal as the sensor probe comes in contact with the liquid. Compared to optical fibre-based sensors reported previously in the literature, the probe profile used in this study differs in terms of its simplicity in design, while exhibiting an excellent signal intensity loss ratio without the need for additional attachments to the probe such as optical prisms. The tests carried out showed that the POF sensor is capable of detecting a variety of fluids. Exhibiting good signal stability, the sensor also detects the liquid level reliably when the liquid rises or falls to the predetermined level. The responsiveness of the optical fibre sensor was evaluated by simulating different rates at which the liquid rises by immersing the sensor tip into the liquid and vice-versa at various speeds ranging from 1 mm/min to 500 mm/min.     

Flood Management in Japan—From Rivers to Basins

Abstract

The River Commission of the Ministry of Construction in Japan recommended a basin response to floods in its December 2000 Interim Report to Minister of Construction. This is practically an official declaration of the policy accepting inundation in habited areas. By this policy shift, it is anticipated that more basin response measures and non-structural measures against floods will be promoted to complement structural measures such as continuous levees and dams. Such a policy is not new in the world but is a significant governmental move in Japan, a densely populated, highly developed, and highly flood hazardous country. Although living with floods is a universal coping strategy, the implementation of measures should be different from region to region reflecting region's nature and socio-economic conditions. This paper reviews the flood fighting history of Japan and her statutory evolution against floods and shows the process by which the ever-increasing flood damage potential and the recent increase of flood damages necessitated the official move in flood control management from rivers to basins.     

混凝土面板堆石坝坝体过水保护

天生桥一级水电站混凝土面板堆石坝堆石填筑量大，在大坝填筑施工的第一个汛期，坝体内预留底宽１２０ｍ、边坡１：１．４的梯形泄槽，该泄槽与导流隧洞联合运行承担１９９６年汛期泄洪任务。泄槽过流按３０年一遇洪水标准加以保护，选用直径大于２０ｃｍ的干砌块石护坡，其表面覆盖铁网，并用钢筋框格固定，泄槽重要部位采用钢筋铁丝笼充填块石加以保护。泄槽过流后，抽水检查结果表明，过流保护面无任何冲刷破坏，达到了安全渡汛的     

基于WebGIS的防汛信息系统

分析了WebGlS的实现技术及特点,结合防汛信息系统的需求,给出了基于WebGIS的防汛信息系统的功能结构和体系结构。采用ⅡS作为Web服务器、ArcIMS作为地图服务器完成了系统功能设计,实现了网上数字地图的处理、传送,以及基于地图的防汛信息查询。     

PS,LS和煤油体系的界面张力

本文以石油磺酸盐(PS)、木质素磺酸盐(LS)和煤油体系为对象,研究了PS/LS比、盐度、醇、Na_2SiO_3及聚合物对体系界面张力(IFT)的影响,探讨了PS与各组分间的相互作用,结果发现,在一定盐度和混合醇(正丁醇+异丙醇)浓度下,PS/LS>0.3/0.7时,体系可形成中相微乳液,IFT值达1×10~(-3)mN/m左右;LS和聚合物的存在使IFT升高;在表面活性剂驱油体系中,可用廉价的LS部分代替PS。