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An increasing impervious area is quickly extending over the Wu‐Tu watershed due to the endless demands of the people. Generally, impervious paving is a major result of urbanization and more recently has had the potential to produce more enormous flood disasters than those of the past. In this study, 40 available rainfall–runoff events were chosen to calibrate the applicable parameters of the models and to determine the relationships between the impervious surfaces and the calibrated parameters. Model inputs came from the outcomes of the block kriging method and the non‐linear programming method. In the optimal process, the shuffled complex evolution method and three criteria were applied to compare the observed and simulated hydrographs. The tendencies of the variations of the parameters with their corresponding imperviousness were established through regression analysis. Ten cases were used to examine the established equations of the parameters and impervious covers. Finally, the design flood routines of various return periods were furnished through use of approaches containing a design storm, block kriging, the SCS model, and a rainfall‐runoff model with established functional relationships. These simulated flood hydrographs were used to compare and understand the past, present, and future hydrological conditions of the watershed studied. In the research results, the time to peak of flood hydrographs for various storms was diminished approximately from 11 h to 6 h in different decrements, whereas peak flow increased respectively from 127 m3 s?1 to 629 m3 s?1 for different storm intensities. In addition, this study provides a design diagram for the peak flow ratio to help engineers and designers to construct hydraulic structures efficiently and prevent possible damage to human life and property. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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雷州半岛硅藻土煅烧中的结构变化 总被引:5,自引:4,他引:5
本文应用X射线衍射、红外光谱、扫描电镜等手段,对广东海康、徐闻的硅藻土在煅烧过程中热结构变化进行了探讨。结构表明,煅烧使硅藻内部矿物的微观结构发生变化而引起形变,主要为SiO2从无序含水的蛋白石转变为有序的方石英晶体。形变温度随其硅藻的种类和杂质不同而各异。本研究为这两地硅藻土的开发提供了科学依据。 相似文献
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华北地区在侏罗纪和白垩纪分别发生了两次不同性质的岩浆活动,早期形成一套高锶石英闪长岩,另一期为钾玄岩系。两套岩石分别代表地壳加厚和减薄的构造背景,两次岩浆活动的转折期大致在130Ma左右,此外,华北地区自垩纪广泛分布的碱性岩同样表明区域内在白垩纪曾发生过强烈的岩石圈伸展作用。这一地质特征与区内盆地地震剖面、造山带构造活动年龄、变质核杂岩的年龄、早向坚世太平洋板块运动方向和运动速率的改变以及郯庐断裂左旋运动年龄等地质资料相佐证。因此华北地区岩石圈减薄作用主要发生在早向垩世时期,晚侏罗世——早白垩世是华北地区中生代重大构造发生的转折点。 相似文献
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I.StduyAreaPUschRjdgeoftheSantaCatalinaMountains,CoronadONaionalForest,SoutheastArizona,wasselectedasastudyareafOrvegetationmopingandatestoftheroleOfGISinaidingrem0teIysenseddataclassificati0n.BeinganepitOmeoftheSantaCatalinaMountains,PUscllmdgeiscomprisedOf23O.65sqUarelQnoflandIocatedonthesouthwesternPOrti0noftheSantaCarelinaRangerDistrictOftheCoronadoNationalForest.ltprovidesasharPcontrastbebeenthenamralruggdnessOftheSantaCatalinaMountainsandtheCityOfTucson,Arizona,araPdl… 相似文献
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利用2014—2016年第二代月动力延伸预测模式业务系统(DERF2. 0)直接输出及预报员预报的贵州省气温和降水预报数据、贵州省84站观测数据,采用Ps、Cs和Zs 3种评分方法评估了DERF2. 0对贵州月气温、降水和月内强降水过程的预测性能,并与预报员业务值班发布的预报质量进行对比分析,系统性地对DERF2. 0产品在延伸期/月尺度的预测效果进行检验评估。结果表明:DERF2. 0月预测产品总体上对贵州气温的预测性能优于降水,气温偏高预测的可参考性高于其对气温偏低的预测。DERF2. 0预报月气温的Ps评分较预报员略高,月降水较预报员略低,总体来看DERF2. 0月预测效果较预报员综合预报略差且预报性能较不稳定。预报员预测数据的Zs和Cs评分总体高于DERF2. 0预测数据,但DERF2. 0预测数据的Zs和Cs评分较预报员逐年提高,尤其在整个雨季时段较为明显。DERF2. 0对主汛期(6—8月)的预报准确率较整个雨季期(4—10月)略高。 相似文献
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目前国内既能处理磁力勘探数据又能处理激电中梯扫面数据的软件并不多。与其它地球物理软件相比较,澳大利亚公司开发的Modelvision软件具有操作简单、运行效率高、处理效果好等优点。本文以安徽某地金属矿勘查为例,介绍了Modelvision软件在磁法勘探与激电中梯扫面中的研究应用。 相似文献