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91.
以金沙江中游梯级水电站水情自动测报系统的建设和运行管理实践经验为基础,总结和探索流域梯级水电站水情自动测报系统建设和运行管理的新思路,以期对今后流域水情测报系统的建设和运行管理起到借鉴作用。 相似文献
92.
本文针对鄱阳湖水利枢纽工程修建后将发挥的作用和可能产生的影响,采用现场调研、实测资料分析和数学模型计算等研究手段,从鄱阳湖流域水资源演变趋势及开发利用状况,三峡水库运用对长江中下游河道冲淤变化及江湖关系的影响,枢纽工程对水资源、防洪、湖区水环境和鱼类的影响,枢纽工程合适的下闸蓄水时期和蓄水位,工程闸门型式及鱼道建设等方面进行了研究,试图为鄱阳湖水利枢纽工程项目立项和规划设计提供科技支撑。 相似文献
93.
对大型抽水蓄能电站首机首次水泵工况启动试验方式关注的主要技术问题,重点研究了9个技术难点和特点问题,提出分析意见和风险性评估。 相似文献
94.
综合分析了应对20081106洪水的乌江梯级水电站联合调度效果及经验,并应用多元线性回归方法构建了乌江梯级水电站总发电量拟合模型,识别影响乌江梯级水电站发电量的关键因素及影响程度。结果表明,洪家渡和东风流域累计平均降雨在2008年10月和11月期间,分别比多年平均同期偏多40%~54%和71%~112%,经乌江梯级水电站联合优化调度后,梯级综合月末可用水量分别比2005~2007年同期偏高136%和162%,梯级综合发电量比2005~2007年同期分别偏多9%和141%,梯级水电站联合优化调度效果显著,且出库流量及龙头电站洪家渡的水位和月末可用水量是影响乌江梯级总发电量的决定性因素。研究结果对于从梯级水电站联合调度角度减缓极端天气事件对水电行业的影响具有重要的参考价值。 相似文献
95.
以黑河市典型农作物大豆和小麦为研究对象,利用气象数据和相关研究成果,计算了黑河地区大豆和小麦的需水规律和需水量,并和降水分布和有效降水量进行对比。研究发现在小麦生长阶段内,小麦需水量和降水量基本同步,但是6月-7月份亏水量约72 mm。在大豆整个生育期内,各月有效降水量均不能满足大豆的需水量,6月份缺水量最大为88 mm,生育期内共缺水量182 mm。考虑到当地矮杆作物灌水技术一般采用喷灌,建议灌水定额采用40 mm,小麦需在6月份喷灌一次,大豆在整个生育期内喷灌4~5次,以实现小麦和大豆的高产稳产。 相似文献
96.
本文介绍了在复杂地形地貌条件下长距离、大流量供水渠道防洪建筑物的设计成果,总结了在工程运行过程中取得的实践经验,以期为今后类似工程的防洪设计与运行提供借鉴。 相似文献
97.
结合我国大型引调水工程建设情况。逐一描述了南水北调东线工程(江苏省段及山东省段)、南水北调中线工程及河北省南水北调配套工程的自动化系统设计情况.进而分析了各大型引调水工程自动化系统在管理机构设置、调度控制方式、系统结构及功能模块配置、通信传输网络结构等方面的不同,为全面提升河北省南水北调配套工程自动化系统设计提出借鉴经验,具有现实意义及应用价值。 相似文献
98.
Abstract In this paper, the results of utilizing a deterministic dynamic programming model for operation of Lar Reservoir in Iran are discussed. This reservoir has experienced extensive seepage from the start of its operation. The optimization model consists of a three-step cycle, which began with the optimization of reservoir operation for a given set of streamflows. The optimal policies are then analyzed in a regression procedure to obtain a set of operating rules. After the first run, operating rules from the previous run were placed as a new constraint on the water releases with some pre-assigned tolerance and the cycle continues. The model also consisted of mathematical functions for modeling the seepage from Lar Reservoir as a function of storage head in the reservoir. The loss function in the model was also modified in order to incorporate parameters that reduce the seepage. Results of different scenarios showed the significant effect of optimal policies on reduction of seepage and increasing the reliability of water supply to Tehran Metropolitan Area. A pumping station was also proposed to utilize the inactive part of the reservoir, in access of over 100 MCM, in order to reduce the seepage. The effectiveness of different pumping capacities to reduce the seepage was also investigated. 相似文献
99.
Gert A. Schultz 《国际水》2013,38(1):96-109
Abstract Presently a change of paradigm in the field of planning and operation of water management schemes can be observed. The introduction of the principle of sustainable development by the United Nations and the principle of integrated river basin management postulated by the European Union play a major role in this context. Introduction of these new principles requires development of new planning tools, which in turn require a much better data basis than available hitherto. This paper deals with new data types already partly available now, partly to be expected to be developed in the medium-range future. The present data situation is discussed, along with the obvious deficits of conventional data. New data types will not be limited to point measurements, but rather must comprise information covering large areas with a higher resolution in time and space than presently available. Remote sensing data will play a more important role in the future. Furthermore, digital maps, digital elevation models, etc. are also of growing importance and will be processed, together with remote sensing and other data, within Geographical Information Systems of future generations also exposing the potential for working with multi-temporal imagery. In the paper it is shown that in the future more accurate data will be available, not only in terms of data quality, but also resolution in time and space. It is shown how the new types of hydrometeorological data postulate new types of hydrological models. Here, distributed system models are of growing importance. Furthermore, it is shown how the combination of remote sensing with other information leads to new data types that allow integrated planning of water resources systems. The potential of real time data is highlighted, particularly in the context of real time operation of water resources systems, especially for flood control. The potential of large-scale data schemes in the context of regional and continental water management schemes is discussed. Global atmospheric models coupled to hydrological models are discussed, and their potential to consider long-distance effects of certain phenomena (e.g., El Niño) are mentioned. For sustainable development of water resources, the potential of long-term data prediction scenarios is evaluated, and an example of this principle for planning future water supply systems is presented. The paper ends with a vision of future developments in planning water management schemes on the basis of new data types 相似文献
100.