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991.
江苏省近40年洪涝灾害概况及防洪对策 总被引:2,自引:0,他引:2
本文分析了江苏省40a来洪涝灾害概况及1991年特大洪涝受灾情况。针对江苏实际,提出了减灾对策。 相似文献
992.
Jy S. Wu Ellis L. King Michael Wang 《Journal of the American Water Resources Association》1985,21(3):417-421
Traditionally, identification of the Muskingum routing coefficients has been based on observations of the linearity of a loop formed by graphically plotting a forward and a reverse path. This graphical procedure is time-consuming and may not minimize the error of estimation. A procedure was developed to improve the drawbacks of the graphical method. This procedure calls for (a) the use of least square regression on the forward and reverse paths to determine their respective slopes, and (b) the use of statistical t-test to evaluate the hypothesis that these two slopes are equal. The computational procedure is repeated, using incremental values of the flow weighting coefficient, x. A graph of the computed t-value versus x can be constructed. The optimal value of x, as read from the graph, occurs at the minimum computed t-value. The procedure has been demonstrated superior to the graphical method for three illustrative examples, resulting in a reduction of the error squares by factors ranging from 5 to 6. 相似文献
993.
电石渣-铁屑法去除硫酸废水中的氟和砷 总被引:10,自引:0,他引:10
对各种处理含氟、砷废水的方法进行了探讨,选择了以电石渣和废铁屑为药剂去除硫酸废水中氟和砷的方法,取得了较好的效果。该法以废治废、工艺简便、运行费用低,处理后的废水可达排放标准。 相似文献
994.
金磊 《中国安全科学学报》1995,(2)
阐述建立风险学的重要性,探讨了开展安全减灾风险评价与管理的关键问题。概要介绍国内外风险水平的表征、识别方法及指标体系,并提出风险管理的基本原则。引入风险地图、危机管理、风险数学、应急与预警等现代概念及方法,基本反映了在瑞典召开的“新区开发中的风险科学与管理”国际会议的内容。 相似文献
995.
简述了我国重大工业事故发生的主要原因,提出了建立重大事故预防控制体系的建议,制定《重大事故预防和控制法》,实行重大危险源上报、登记、评价、分级监察管理,建立国家、省、市三级重大事故应急反应系统和重大危险源动态监控网络系统。 相似文献
996.
本文以定量分析为主要手段,详细研究了吉林省农业病虫害发生的时间过程规律和空间分布规律,深入探讨了环境因子对农业病虫害的影响,综合评价了病虫害防治工作的效果。 相似文献
997.
Ming‐Hsi Hsu Chi‐Ray Wu Wen‐Cheng Liu Albert Y. Kuo 《Journal of the American Water Resources Association》2006,42(4):901-914
ABSTRACT: To comprehend the distributions of salinity, temperature, and suspended sediment in the Danshuei River estuary in Taiwan, monthly field surveys were conducted in 2003. These included several high and low slackwater surveys and intensive surveys. The results show that the Danshuei River estuary is predominately a partially mixed estuary. The highest concentration of suspended sediment is typically observed at the Chung‐Hsin Bridge, the most upstream sampling station. The suspended sediment concentration exhibits a general decreasing trend in the downstream direction. It may be concluded that the sediments mostly come from the upstream reach. A locally high concentration of suspended sediment is found at the Kuan‐Du station because of the local deep channel bathymetry and two‐layered estuarine circulation. A vertical two‐dimensional hydrodynamic and sediment transport model is applied to investigate the tidally averaged salinity distribution, residual circulation, and suspended sediment concentration. The modeling results reveal that, under the Q75 flow condition (i.e., low flow), a turbidity maximum occurs at the Kuan‐Du station due to the strong estuarine circulation. The model simulation with a much higher river flow condition results in a weaker residual circulation and weaker turbidity maximum. 相似文献
998.
Jing Wu Shaw L. Yu Rui Zou 《Journal of the American Water Resources Association》2006,42(5):1193-1204
ABSTRACT: Watershed management strategies generally involve controlling nonpoint source pollution by implementing various best management practices (BMPs). Currently, stormwater management programs in most states use a performance‐based approach to implement onsite BMPs. This approach fails to link the onsite BMP performance directly to receiving water quality benefits, and it does not take into account the combined treatment effects of all the stormwater management practices within a watershed. To address these issues, this paper proposes a water quality‐based BMP planning approach for effective nonpoint source pollution control at a watershed scale. A coupled modeling system consisting of a watershed model (HSPF) and a receiving water quality model (CE‐QUAL‐W2) was developed to establish the linkage between BMP performance and receiving water quality targets. A Monte Carlo simulation approach was utilized to develop alternative BMP strategies at a watershed level. The developed methodology was applied to the Swift Creek Reservoir watershed in Virginia, and the results show that the proposed approach allows for the development of BMP strategies that lead to full compliance with water quality requirements. 相似文献
999.
1000.