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水平分辨率对DEM流域特征提取的影响 总被引：7，自引：0，他引：7
选取石质山地与黄土丘陵过渡区宛川河流域作为研究区,利用1∶5万、水平分辨率10~100 m栅格DEM提取流域特征参数进行分析。结果表明:DEM水平分辨率对数字河网的提取精度有影响,提取的流域面积差别很小,河流长度、河道总长、河道坡度以及河网密度有偏差,流域平均坡度变化明显,长度和坡度特征参数的变化导致流域汇流时间及滞时不一致。 相似文献
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《国际泥沙研究》1999,(2)
ICONDUCTINGASEDIMENTATIONSURVEYTOCONFIRMISSUESIn1996,ElectricPowerResearchinstitilteandtheFERCjointlyconductedasedimentationsurveyofprimarilyNFHPreservoirsintheUnitedstates.Theprimarypurposesofthesurveyweref(l)toascertainthescopeandseriousnessofsedimentationproblemsinthereservoirs,(2)toexplorethefeasibilityofapplyingmoderntechnologiestomitigatesedimentationproblems,(3)todeterminetheneedsfortechnicalguidelines,(4)toassistFERCstaffinthelicensingofhydroelectricprojectswith… 相似文献
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The Milky Way is made up of a central bar, a disk with embedded spiral arms, and a dark matter halo. Observational and theoretical constraints for the characteristic parameters of these components will be presented, with emphasis on the constraints from the dynamics of the Milky Way gas. In particular, the fraction of dark matter inside the solar radius, the location of the main resonances, and the evidence for multiple pattern speeds will be discussed.Invited talk at the AAS Division on Dynamical Astronomy meeting, Santa Barbara, April 2005 相似文献
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Résumé L'objectif de ce travail est de fournir aux hydrologues travaillant sur l'Algérie du Nord un modèle numérique de terrain (MNT) permettant la mise en ?uvre de méthodes d'estimation régionales de paramètres hydrologiques tels que les débits de crue instantanés décennaux ou les apports moyens annuels. Il doit permettre une détermination satisfaisante des contours des bassins versants et l'obtention de paramètres morphométriques comparables entre eux sur l'ensemble de la zone d'étude. Le MNT que nous proposons est un compromis entre des tailles de pixels petites donnant une bonne précision et des pixels plus grands permettant de couvrir uniformément la zone. Nous montrons que le MNT à la maille de 100 m est parfaitement adapté sous réserve de l'avoir préalablement corrigé manuellement dans les zones endoréiques et dans les zones relativement planes. Ce MNT permet de retrouver correctement les principaux paramètres morphométriques utilisés en hydrologie. Nous mettons donc à la disposition des hydrologues ce MNT à 100 m dans une projection Lambert bien adaptée aux besoins de l'hydrologie algérienne. Editeur Z.W. Kundzewicz Citation Rezak, S., Laborde, J.-P., et Errih, M., 2012. Validation d'un modèle numérique de terrain adapté à la modélisation hydrologique régionale sur l'Algérie du Nord. Hydrological Sciences Journal, 57 (5), 928–941. 相似文献
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林叔忠 《地球科学与环境学报》1994,(1)
本文介绍了高压喷射灌浆技术在北江大堤强透水堤基处理中的应用．文中在分析堤基地层结构特征和物性指标的基础上，论述了高喷防渗墙的设计施工参数，根据已有围井检验结果，分析了各种地层高喷防渗墙的防渗效果，提出了用“单位渗水率”指标评价围封质量的新方法．文中根据大堤渗流观测资料和检验指标“单位渗水率”，建立了高喷防渗墙垂直截流堤基的渗流计算公式，并得出高喷防渗墙能有效地抑制住大堤堤基的渗流形变． 相似文献
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HUGH W. CALKINS NANCY J. OBERMEYER 《International journal of geographical information science》2013,27(3):341-351
Abstract Understanding the use and value of geographical information in decision making has been identified as crucial to the further development of geographical information systems and related spatial analysis techniques. Research into the use of geographical information will be through surveys and case studies. A taxonomy for investigating the use of geographical information and its associated value is needed to structure the surveys and case studies. This paper presents an initial attempt at such a taxonomy, intended to support continuing research into the use and value of geographical information. The survey methodology to be supported will be mostly telephone and/or mail questionnaires, and this has influenced the structure of the taxonomy. The goal of this work is to create a taxonomy suitable for use in surveys that will enhance the understanding of the use and value of geographical information in decision making. 相似文献
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以浙江省瓯江流域为例,基于SWBD修复的SRTM DEM数据,采用Arc Hydro Tools水文分析工具自动提取瓯江水系,并分地貌、分河流等级地定量评价水系数据精度,开展1∶250 000水系自动更新的可行性研究。结果表明：①SWBD修复的SRTM DEM的空白区域面积为54.78 km2,有效地弥补了SRTM DEM的数据缺失,进而提高了水系提取的准确度和精度;②与1∶250 000水系数据相比,基于SWBD修复后的SRTM DEM,在小起伏山、中起伏低山、低海拔丘陵上提取的水系数据精度高于其他地貌,而干流、一级支流、二级支流的精度又高于三级支流;③以资源三号卫星ZY-3遥感影像为参照,从水系上采集同名点反复比较点位精度后发现,利用SRTM DEM提取的水系符合制图规范和测绘内业规范（限差1 mm）,可以满足1∶250 000水系自动更新的要求。 相似文献
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Osvaldo Salazar Abraham Joel Ingrid Wesström Harry Linnér R. Wayne Skaggs 《水文研究》2010,24(26):3837-3851
The field hydrology model DRAINMOD integrated with Arc Hydro in geographical information system (GIS) framework (Arc Hydro–DRAINMOD) was used to simulate the hydrological response of a coastal watershed in southeast Sweden. Arc Hydro–DRAINMOD uses a distributed approach to route water from each field edge to the watershed outlet. In the framework the Arc Hydro data model was used to describe the stream network in the watershed and to connect the individual simulated DRAINMOD‐field outflow time series from each plot using Arc Hydro schema‐links features, which were summed at Arc Hydro schema‐nodes features along the stream network to generate the stream network flow. Hydrology data collected during six periods between 2003 and 2008 were used to test Arc Hydro–DRAINMOD and its performance was evaluated by considering uncertainties in model inputs using generalized likelihood uncertainty estimation (GLUE). The GLUE estimates obtained (uncertainty bands 5% and 95%) agreed satisfactorily with measured monthly discharges. The percentage of time in which the observed discharges were bracketed by the uncertainty bands was 88% in calibration periods and 75% in validation periods. Although monthly time step simulations showed good agreement with observed discharges during the two main discharge events in spring, the contradictory daily time step results indicate that the watershed response simulations on a daily basis need to be improved. The uncertainty analysis showed that in periods of higher discharge, such as spring periods, the uncertainty in prediction was higher. It is important to note that these uncertainty estimations using the GLUE procedure include the uncertainties in measured discharge values, model inputs, boundary conditions and model structures. It was estimated that stream baseflow represented 42% of the total watershed discharge, but further research is needed to confirm this. These results show that the new Arc Hydro–DRAINMOD framework is applicable for predicting discharge from artificially drained watersheds in southeast Sweden. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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尾矿库是矿山企业选矿的必要设施,同时对周围环境也是一个重大的危险源。为研究流域范围内尾矿库的溃坝路径以及对矿区地表造成的风险,以赤城县为例,利用GF-1高分辨率遥感影像,基于遥感RS（Remote Sensing）及地理信息系统GIS（Geographic Information System）手段对尾矿库的流域风险进行了监测分析。首先,通过分析尾矿库在遥感影像上的纹理、色调、形状以及大小等特征,制作了用于目标检测的尾矿库样本集,然后,在原始SSD目标检测网络基础上添加了反卷积模块和连接模块构建多尺度融合目标检测算法MSF_SSD,在目标检测结果基础上使用PSPnet算法实现尾矿库结构分割,得到了尾矿库内部结构—坝体以及库区,运用RS与GIS技术对尾矿库的上游汇水面以及事故可能径流进行提取,进而基于Arc Hydro模型模拟尾矿库的溃坝路径。最后,通过构建溃坝路径的缓冲区,得到尾矿库发生溃坝所造成的地物影响范围及面积。研究结果表明：赤城县尾矿库的溃坝路径总体是从西向东,从北向南,受溃坝影响的地物总面积达到480 km2。其中,林地176.52 km2,耕地175.52 km2,城市建设用地43.74 km2,农村建设用地2.47 km2,水体17.72 km2,草地和牧场分别为3.60 km2、1.22 km2。研究成果可用于分析尾矿库溃坝造成的地物损失以及影响范围面积等信息,提升尾矿库的风险管理水平及应急响应能力,为有关部门制定决策提供理论依据。 相似文献