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911.
A prime requirement for hydrological applications,such as sediment budgeting or numerical modelling,is that produced Digital Terrain Models(DTMs)accurately represent the shape of landforms,especially for river reaches where data are not homogeneous.DTM error is a function of data point measurement accuracy and density and also of the field survey strategy when limited amounts of data will be acquired.This paper aims to advance the importance of the field survey strategy for the specific,but common cases,where only limited topographic data will be available.This methodology is based on the idea that any feature can be properly described by a set of cross sections and breaklines describing both main and secondary directions of the flow.Then,a longitudinal linear interpolation can be applied to the defined homogeneous zones.This morphologically oriented(MO)method that includes data acquisition strategy and interpolation,was validated using a reference DTM derived from LiDAR measurements.An estimation of the uncertainties also is suggested based on the distance of the nearest point and the local slope using a geographically weighted regression.The proposed MO method is typically applicable to Alpine river reaches characterized by multiple channels that may always be underwater and not navigable such as an alternate bar system with secondary and transverse channels. 相似文献
912.
913.
Introduction
In recent years, all kinds of observation networks of seismology have been established, which have been continuously producing numerous digital information. In addition, there are many study results about 3D velocity structure model and tectonic model of crust (Huang and Zhao, 2006; Huang et al, 2003; Li and Mooney, 1998), which are valuable for studying the inner structure of the earth and earthquake preparation process. It is badly needed to combine the observed data, experimental study and theoretical analyses results by the way of numerical simulation and develop a database and a corresponding application platform to be used by numerical simulation, and is also a significant way to promote earthquake prediction. 相似文献
914.
915.
Salvatore Grimaldi Fernando Nardi Francesco Di Benedetto Erkan Istanbulluoglu Rafael L. Bras 《Advances in water resources》2007
Spurious pits in digital elevation models (DEMs) are traditionally removed by filling depressions, often creating flat regions that lead to inaccurate estimation of landscape flow directions. In this study, a physical approach based on a simple landscape evolution model is proposed for DEM pit removal. This method, an alternative to traditional geometrical procedures, enforces more realistic slopes and flow directions on topography. The procedure is compared with the method most commonly used in the literature and distributed with commercial GIS software where, generally, elevations of a depression are increased up to the lowest value among neighbouring cells. Several tests are performed and parameters sensitivity is carried out in order to demonstrate the performance of the proposed model as compared to traditional methods. 相似文献
916.
介绍了山西数字测震台网EDAS-24IP+BBVS型数字地震仪传递函数的特征和测定方法,对地震仪阶跃标定及正弦标定计算分析,得出台站工作状态、地震计周期、阻尼、主零极点参数的变化情况;并对数字地震仪的频带范围、通频带的平坦程度、三分向幅频响应的一致性进行了讨论和分析。认为台网的系统特性是稳定和可靠的。 相似文献
917.
目前虽然有许多种方法可以进行构造裂缝预测,但由于碳酸盐岩发育区裂缝发育的复杂性,需要综合研究构造裂缝定量预测的新方法.本文以哈萨克斯坦扎纳若尔碳酸盐岩凝析油田为研究和应用对象,提出了基于GIS系统的构造裂缝综合分析技术,通过构造DEM滤波分析、综合曲率分析、裂缝地形因子分析以及DEM构造应力场分析,提取与裂缝有关的构造起伏变化和侵蚀程度指标,对于碳酸盐岩储层利用DEM进行古水文地质条件分析,研究古地貌侵蚀和沉积的空间分布情况.根据构造应力场信息,综合分析不同构造部位岩层发生破裂的可能性及破裂程度,预测区域裂缝和局部构造裂缝发育带、发育程度及发育方向,并取得了不错的预测效果. 相似文献
918.
919.
920.
联动应急的工作平台建设是应急处置的一项基础性工作,包括联动应急的指挥平台和信息平台。指挥平台应坚持以应急管理流程为主线来设计,其主要内容包括各类支援平台、相关的数据库、管理指挥中心、各种保障体系等,其实现方式和途径可以设计为多维交互网络模型。联动应急信息平台的建设可从信息接入系统、信息服务系统以及信息交换平台、视讯展示平台等方面进行。 相似文献