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521.
Pao‐Shan Yu Chia‐Jung Chen Shiann‐Jong Chen Shu‐Chen Lin 《Journal of the American Water Resources Association》2001,37(1):151-166
ABSTRACT: A reliable forecasting model is essential in real‐time flood forecasting for reducing natural damage. Efforts to develop a real‐time forecasting model over the past two decades have been numerous. This work applies the Grey model to forecast rainfall and runoff owing to the model's relative ability to predict the future using a small amount of historical data. Such a model significantly differs from the stochastic and deterministic models developed previously. Ten historical storm events from two catchment areas in northern Taiwan are selected to calibrate and verify the model. Results in this study demonstrate that the proposed models can reasonably forecast runoff one to four hours ahead, if the Grey error prediction method is further used to update the output of the model. 相似文献
522.
523.
Dilip Mathur Paul G. Heisey John R. Skalski Daniel R. Kenney 《Journal of the American Water Resources Association》2000,36(4):737-747
ABSTRACT: The hypotheses that fish survival probabilities may be lower (1) at less than peak operating turbine efficiency; (2) at deeper entrainment depth; and (3) with the deployment of extended‐length intake guidance screens, are not supported by results on yearling chinook salmon smolts (Oncorhynchus tshawytscha) at Lower Granite Dam, Snake River, Washington. Estimated 96 h survival probabilities for the six test conditions ranged from 0.937 to 0.972, with the highest survival at turbine operating towards the lower end of its efficiency. A blanket recommendation to operate all Kaplan type turbines within ± 1 percent of their peak efficiency appears too restrictive. Cavitation mode survival (0.946) was comparable to that at peak operating efficiency mode (0.937), as was the survival between upper (0.947) and mid depths (0.937). Survival differed only slightly among three turbine intake bays at the same depth (0.937 to 0.954), most likely due to differential flow distribution. Extended‐length intake fish guidance screens did not reduce survival. However, the sources of injury somewhat differed with depth; probable pressure and shear‐related injuries were common on fish entrained at mid‐depth, and mechanically‐induced injuries were common at upper depth. Operating conditions that reduce turbulence within the turbine environment may enhance fish survival; however, controlled experiments that integrate turbine flow physics and geometry and the path entrained fish traverse are needed to develop specific guidance to further enhance fish passage survival. 相似文献
524.
小龙潭发电厂烟气循环流化床脱硫工程评述 总被引:4,自引:0,他引:4
阐述了小龙潭发电厂100MW机组烟气脱硫工程的工艺原理、系统流程、主要设备等,并结合系统调试过程中发现的问题,对该工艺的运行调试进行了评述。 相似文献
525.
The quality of recyclable and residual municipal solid waste (MSW) is, among other factors, strongly influenced by the seasonal variation in MSW composition. However, a relatively marginal amount of published data on seasonal MSW composition especially in East European countries do not provide sufficient information on this phenomenon. This study provides results from municipal waste composition research campaigns conducted during the period of 2009–2011 in four cities of Eastern European countries (Lithuania, Russia, Ukraine and Georgia). The median monthly MSW generation values ranged from 18.70 in Kutaisi (Georgia) to 38.31 kg capita−1 month−1 in Kaunas (Lithuania). The quantitative estimation of seasonal variation was performed by fitting the collected data to time series forecasting models, such as non-parametric seasonal exponential smoothing, Winters additive, and Winters multiplicative methods. 相似文献
526.
王兴阳 《环境监测管理与技术》2009,21(2):42-44
采用氢化物发生-原子荧光光谱法测定土壤中的镉,优化了试验条件,讨论了共存元素的干扰及消除办法。方法在0μg/L~120μg/L范围内线性良好,检出限为0.003 mg/kg(按取样0.600 g定容至45 mL计),土壤标准样品测定的RSD≤3.7%,加标回收率为94.8%,与石墨炉原子吸收分光光度法的测定结果相吻合。 相似文献