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Cinzia MAZZETTI 《水科学与水工程》2009,2(4):28-39
This study evaluated the application of the European flood forecasting operational real time system (EFFORTS) to the Yellow River. An automatic data pre-processing program was developed to provide real-time hydrometeorological data. Various GIS layers were collected and developed to meet the demands of the distributed hydrological model in the EFFORTS. The model parameters were calibrated and validated based on more than ten years of historical hydrometeorological data from the study area. The San-Hua Basin (from the Sanmenxia Reservoir to the Huayuankou Hydrological Station), the most geographically important area of the Yellow River, was chosen as the study area. The analysis indicates that the EFFORTS enhances the work efficiency, extends the flood forecasting lead time, and attains an acceptable level of forecasting accuracy in the San-Hua Basin, with a mean deterministic coefficient at Huayuankou Station, the basin outlet, of 0.90 in calibration and 0.96 in validation. The analysis also shows that the simulation accuracy is better for the southern part than for the northern part of the San-Hua Basin. This implies that, along with the characteristics of the basin and the mechanisms of runoff generation of the hydrological model, the hydrometeorological data play an important role in simulation of hydrological behavior. 相似文献
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基于DEA模型评价河南省水资源绿色效率、环境效率和经济效率,运用ArcGIS软件分析水资源效率的时空特征,依托GeoDa软件进行相关性分析。结果表明:河南省不同类型水资源效率变化趋势不同,其中水资源经济效率呈现下降趋势,水资源环境效率和绿色效率呈现波动上升趋势;河南省18市水资源效率差距变化趋势不同,其中水资源经济效率差距呈缩小趋势,水资源环境效率和绿色效率差距呈增大趋势,且水资源经济效率明显高于水资源环境效率和绿色效率;河南省水资源经济效率高和中高等级城市、低和中低等级城市各占50%,而水资源环境效率和绿色效率高和中高等级城市、低和中低等级城市则分别占55.6%和44.4%;河南省水资源效率相似的地区存在空间集聚效应,其中水资源经济效率全局空间自相关性呈增强趋势,水资源环境效率和绿色效率全局空间自相关性则呈减弱趋势;河南省水资源经济效率、环境效率和绿色效率低-低集聚地区均为安阳市,经济效率高-高集聚地区为平顶山、许昌、漯河和周口等4市,环境效率高-高集聚地区为平顶山和许昌市,绿色效率高-高集聚地区则为洛阳和许昌市,低-高与高-低集聚地区数都为0。 相似文献
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多年来,黄河泥沙处理一般采用置换法,这种原始的泥沙水体分离方法是利用虹吸管由人工抽取清水,此法存在误差大,工作效率低等问题.因此,笔者结合黄河水文实际,研制了“沙样水体自动控制分离器”,分析器采用单片机自动把清水与泥沙分离开,完成清浑水自动分离过程,该分离器已在黄河山东水文工作中应用,实践证明,不仅提高了泥沙测验精度,而且提高了工作效率,具有一定的推广应用价值. 相似文献
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