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921.
本文系统分析现代灾害的特点;评述灾害研究及灾害学的历史与现状,预测其发展趋势;探讨灾害学的基本范畴,界定其学科体系的总体框架,对灾害研究及灾害学发展中的几个重要问题提出认识与建议。 相似文献
922.
洪水灾害损失信息系统—FLOODIS系统设计 总被引:3,自引:0,他引:3
本文借助遥感技术,设计出一个专题地理信息系统一洪灾损失信息系统FLOODIS,为损失评估模型提供评估区域洪水灾害损失的各种自然地理和社会经济信息以及经系统内专家模块处理后的专题信息,同时对其计算结果进行多种方式输出。 相似文献
923.
本文根据调查分析,指出建设城市防火安全系统的迫切性。阐述了建设城市防火安全系统的基本原理和规划方法。并探讨了城市防火安全系统的运用管理。 相似文献
924.
925.
Robert C. Borden Philip B. Bedient 《Journal of the American Water Resources Association》1987,23(4):629-636
ABSTRACT: A three well injection-production test was performed at the United Creosoting Company (UCC) site in Conroe, Texas, to estimate the effective in situ retardation factors for adsorption and to evaluate the significance of biotransformation in limiting the transport of polycydic aromatics present in the shallow aquifer. The field test was also used as a model to determine if this type of testing would be feasible at other hazardous waste sites. During the test, chloride, a non-reactive tracer and two organic compounds, naphthalene and paradichlorobenzene (pDCB), were injected into a center well for 24 hours followed by clean ground water for six days. Ground water was continuously produced from two adjoining wells and monitored to observe the breakthrough of these compounds. Data from the test were analyzed by comparing the statistical moments of the chloride and organics distributions. Retardation factors for naphthalene and pDCB were estimated to be 1.03 and 0.97 by comparison of the statistical moments. A significant loss of naphthalene and pDCB was also observed during the three well test, apparently due to biotransformation. These results suggest that biotransformation is the major process limiting the transport of naphthalene and similar compounds at the UCC site. 相似文献
926.
M. Hossein Sabet James Q. Coe 《Journal of the American Water Resources Association》1986,22(4):587-596
ABSTRACT: A large-scale simulation/optimization model provides schedules for operation of water and power for the California State Water Project (SWP). The SWP consists of a series of reservoirs linked by rivers, pumping plants, canals, tunnels, and generating plants and is operated by the California Department of Water Resources. The Department provides water to municipal and agricultural users, and manages its electrical loads and resources. The model, therefore, performs hydraulic and electrical computations leading to optimal operation of the entire system. It consists of hydraulic network programming components to meet the storage objectives at all the reservoirs, a linear programming component to determine the schedules at pumping and generating plants, an electrical network programming component to balance electrical loads and resources, and a number of other simulation components. It operates on yearly, weekly, and daily bases. It is primarily used for real-time operation of the SWP and can provide hourly detail schedules which are implemented by the SWP staff via a computerized system. 相似文献
927.
Stephen E. Draper Srinivas G. Rao 《Journal of the American Water Resources Association》1986,22(6):941-949
ABSTRACT: Percent imperviousness is an important parameter in modeling the urban rainfall-runoff process and is usually determined using manual methods such as random sampling or conventional accounting methods. In this study two computerized methods are used for estimating the percent imperviousness of urban watersheds using high altitude remote sensing imagery. These methods include the Laser Image Processing Scanner and the Video-Tape Camera system. Imperviousness is directly estimated in the former method while in the latter it is estimated as a function of the statistics of the responses on emulsions of the imagery. The percent imperviousness computed by utilizing remote sensing imagery was used with the conceptual models of rainfall-runoff models. The models were applied to four urban watersheds and the runoff prediction results indicate that imperviousness determined by using remote sensing imagery was as accurate as that obtained by the manual methods, and that the use of remote sensing imagery requires significantly less time and money. 相似文献
928.
Peter F. M. McLoughlin 《Journal of the American Water Resources Association》1988,24(3):599-607
ABSTRACT: Third World irrigation and drainage systems have experienced major declines recently in both capability and performance. This is due initially to working them well beyond their design capaci-capacities; scouring, sedimentation, and overtopping result. Chronic O&M underfunding then adds heavily to this worsening malaise. International donors have assisted irrigation departments with rehabilitation projects and programs to improve O&M effectiveness on a grand (billions of dollars) scale. Despite their historical propensity to examine, almost fastidiously, program economic justifications (B/C, IRR, etc), the donors apparently have glossed over two basic analytic elements for (a) more spending on O&M as distinct from an equivalent spending on other means to provide farmers with an m3 of water; and (b) different levels of O&M spending on canals and drains. Surely those different levels provide differing benefits, in total, and at the margin. Which level is most economic? This paper identifies these latter analytical issues, posits methodologies key to an O&M spending level analysis, and discusses the information base. Particular attention is paid to identifying relevant costs and benefits, and to suggesting supplementary criteria for O&M spending level selection. The paper is an exercise in delineation of an imminently practical area of irrigation engineering economics. 相似文献
929.
Fuzzy数学在人-机-环境系统工程研究中的应用 总被引:1,自引:0,他引:1
孙洪元 《中国安全科学学报》1995,5(6):33-33
综述了模糊数学在航天人机环境系统工程中的应用和发展。内容包括急性缺氧反应综合评定,人机系统中的控制模型,通风服研制和鉴定以及人体。心脏功能评价等研究领域中模糊数学的应用方法和作用。其研究方法对于一般人机工程的建模和分析具有积极意义。 相似文献
930.
按照校验费和损失费最小以及有效度最大的原则分别给出了安全监测系统校验的等周期模型。当安全监测系统的无故障工作时间服从威布尔分布时,给出了模型的解法。 相似文献