共查询到18条相似文献，搜索用时 125 毫秒
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地形因子作为对地形地貌特征进行数字表达的定量参数,对岩性识别精度的提高具有重要的意义。在对已知岩性类别区域的高程、坡度、剖面曲率、地表粗糙度和地表切割深度等10个地形因子的分类有效性和相关性进行评价的基础上,对地形因子进行筛选并将最佳尺度下的地形因子用于岩性的分类。结果表明,高程、剖面曲率、地表切割深度、地表粗糙度和平面曲率这5个地形因子的组合更具良好的分类效果,且都对应有识别性最好的岩性。在识别岩性类别时加入充分表达其地形特征的最佳地形因子组合有利于提高岩性的识别与分类能力。 相似文献
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《测绘文摘》2003,(3)
Cl]以0031724对DEM地形定t因子挖掘中若干问题的探讨=S恤eKeyPo纽tsinTerr日nVariabloDerivi】lgfromDEMS/汤国安,杨玮莹,杨听(西北大学城市与资源学系)…//测绘科学一2003,28(1)一28一32 在地学研究中,地形结构信息的提取具有重要意义,而如何利用数字高程模型进行提取一直是地学工作者所面临的重要课题。在总结前人研究成果的基础上,从地形特征分析和水系特征分析两方面,比较了利用数字高程模型自动提取地形定量因子的基本原理、方法以及优缺点,并对其中存在的诸多理论与技术问题进行了系统的分析与探讨。图1表3参15解),根据规范和待… 相似文献
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数字高程模型DEM精度研究 总被引：2，自引：0，他引：2
用不同地貌类型地区的实验数据对数字高程模型(规则格网DEM)的格网间距与中误差(RMSE)、平均高程、剖面曲率的关系进行研究,采用比较分析的方法,得到格网间距与中误差的数学模型,可以用通式:Y=A BX CX2表示,并且把地形因子(平均高程、剖面曲率)作为自变量,进一步分析通式中3个系数与地形因子的关系,发现两个地形因子与系数函数关系比较相似,并得到Y=A BX CX2 DX3的数学模型。由验证结果表明,所得模型效果良好。 相似文献
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数字高程模型(DEM)是地理信息系统(GIS)重要的空间地理信息,是地理信息系统(GIS)进行地形分析的核心数据。模型构建方法的选择是数字高程模型的核心问题,它直接影响数字高程模型的质量,贯穿于数字高程模型生产制作的全过程。数字高程模型有三种数据结构形式:规则格网数据结构、不规则三角网结构和等高线结构。在通常的使用中,规则格网形式的数字高程模型是使用最为广泛的一种,也是建立最为容易的。为此,本文着重对规则格网的构建方法中的内插方法进行了探讨。 相似文献
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基于等高线的几个自动推理问题 总被引：1，自引：0，他引：1
在数字化背景下,人们更多地利用像数字高程模型或数字地形高程模型这样的数字产品来处理类似地形推理的一些问题,而都没有讨论根据一组地形等高线进行推理的可供选择的办法.详细论述如何利用等高线来进行查询点的高程、方向角和坡度等地形要素的推理计算. 相似文献
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针对传统景观格局分析方法的数据局限性,该文提出了一种基于数字高程模型地形信息量的景观格局预测分析方法。结合信息熵理论,利用数字高程模型计算地形信息量,研究不同分级地形信息量下景观格局特征的变化特征,以及不同景观类型在不同地形信息量等级的分布特征,对具有相似地形特征的区域建立利用地形信息量对其景观格局特征进行预测分析的方法。该文选择珠海市地形特征相似的两个区域进行了试验分析,对珠海市斗门区建立基于数字高程模型地形信息量的景观格局预测方法,预测在相似地形特征下南坪镇的景观格局特征,并以南坪镇真实的景观特征进行验证。实验结果显示,基于数字高程模型地形信息量的邻域景观预测分析方法不仅能正确预测分析不同地形信息量下的景观分析指数,同时也能正确预测不同景观类型的空间分布特征。 相似文献
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胡启明 《测绘与空间地理信息》2017,(4)
地形与地貌是数字地形分析中重要的自然地理要素,数字高程模型中蕴含着丰富的地形地貌信息,从中提取地形特征线信息是当前地学研究的热点之一。目前,很多学者使用不同的方法来研究地形特征线的提取,但是仍然存在着许多不足之处。本文对这些方法进行了介绍,对各种方法的研究现状展开综述并分析了优点和不足,最后对特征线提取方法存在的主要问题进行总结和展望。 相似文献
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在综合基于离散点数模和三角网数模生成DEM两种方法优点的基础上 ,提出了一种基于离散无序点的快速生成DEM的方法。该方法有内插速度快、精度高及占用内存小的优点。 相似文献
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Digital elevation model (DEM) has a variety of applications in GIS and CAD. It is the basic model for generating three-dimensional terrain feature. Generally speaking, there are two methods for building DEM. One is based upon the digital terrain model of discrete points, and is characterized by fast speed and low precision. The other is based upon triangular digital terrain model, and slow speed and high precision are the features of the method. Combining the advantages of the two methods, an algorithm for generating DEM with discrete points is presented in this paper. When interpolating elevation, this method can create a triangle which includes interpolating point and the elevation of the interpolating point can be obtained from the traingle. The method has the advantage of fast speed, high precision and less memory. 相似文献
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Algorithm for generating dem based on cone 总被引：1，自引：0，他引：1
JIANG Hongfei 《地球空间信息科学学报》2000,3(3):30-33
Digital elevation model (DEM) has a variety of applications in GIS and CAD.It is the basic model for generating three-dimensional terrain feature.Generally speaking,there are two methods for building DEM.One is based upon the digital terrain model of discrete points,and is characterized by fast speed and low precision.The other is based upon triangular digital terrain model,and slow speed and high precision are the features of the method.Combining the advantages of the two methods,an algorithm for generating DEM with discrete points is presented in this paper.When interpolating elevation,this method can create a triangle which includes interpolating point and the elevation of the interpolating point can be obtained from the triangle.The method has the advantage of fast speed,high precision and less memory. 相似文献
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针对数字地球的开源框架平台的搭建,研究了OSGEarth数字地球开源库的整体框架、实时地形渲染机制及三维地形场景中的交互响应机制,并结合Qt绘图引擎,设计了基于Qt平台下的数字地球平台,利用该框架实现矢量、影像、高程数据的加载和坐标查询、距离测量、注记符号添加等地理信息查询功能,通过加载Google全球影像与地形数据实现三维地形场景的渲染,实现地理信息查询功能验证了该数字地球平台的可用性,拓展了三维地理信息系统的研究方向。 相似文献
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Abstract<title/>When the source data for the digital elevation model (DEM) are not known and any additional information or features such as skeleton lines of terrain is not available, a triangular regular network (TRN) is constructed with simple subdivision using one or two diagonals uniformly. Such a model gives inaccurate directions for interpolation because of the inaccurate diagonals used in triangulation and thereby, results in inaccurate contours representing artificial terrain features. In this study, a new method is developed based on slope information computed at DEM points determining accurate diagonals in the subdivision process, which is beneficial not only through the skeleton lines of a terrain but also all over the DEM. Consequently, it is shown that the proposed method is able to build a high fidelity TRN from a DEM without any additional information or features. 相似文献
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The Effect of DEM Raster Resolution on First Order, Second Order and Compound Terrain Derivatives 总被引：8，自引：0，他引：8
Stefan Kienzle 《Transactions in GIS》2004,8(1):83-111
It is well known that the grid cell size of a raster digital elevation model has significant effects on derived terrain variables such as slope, aspect, plan and profile curvature or the wetness index. In this paper the quality of DEMs derived from the interpolation of photogrammetrically derived elevation points in Alberta, Canada, is tested. DEMs with grid cell sizes ranging from 100 to 5 m were interpolated from 100 m regularly spaced elevation points and numerous surface‐specific point elevations using the ANUDEM interpolation method. In order to identify the grid resolution that matches the information content of the source data, three approaches were applied: density analysis of point elevations, an analysis of cumulative frequency distributions using the Kolmogorov‐Smirnov test and the root mean square slope measure. Results reveal that the optimum grid cell size is between 5 and 20 m, depending on terrain com‐plexity and terrain derivative. Terrain variables based on 100 m regularly sampled elevation points are compared to an independent high‐resolution DEM used as a benchmark. Subsequent correlation analysis reveals that only elevation and local slope have a strong positive relationship while all other terrain derivatives are not represented realistically when derived from a coarse DEM. Calculations of root mean square errors and relative root mean square errors further quantify the quality of terrain derivatives. 相似文献
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Extraction of morphotectonic features from DEMs: Development and applications for study areas in Hungary and NW Greece 总被引：1，自引：0，他引：1
A procedure for the consistent application of digital terrain analysis methods to identify tectonic phenomena from geomorphology is developed and presented through two case studies. Based on the study of landforms related to faults, geomorphological characteristics are translated into mathematical and numerical algorithms. Topographic features represented by digital elevation models of the test areas were extracted, described and interpreted in terms of structural geology and geomorphology. Digital terrain modelling was carried out by means of the combined use of: (1) numerical differential geometry methods, (2) digital drainage network analysis, (3) digital geomorphometry, (4) digital image processing, (5) lineament extraction and analysis, (6) spatial and statistical analysis and (7) digital elevation model-specific digital methods, such as shaded relief models, digital cross-sections and 3D surface modelling. A sequential modelling scheme was developed and implemented to analyse two selected study sites, in Hungary and NW Greece on local and regional scales. Structural information from other sources, such as geological and geophysical maps, remotely sensed images and field observations were analysed with geographic information system techniques. Digital terrain analysis methods applied in the proposed way in this study could extract morphotectonic features from DEMs along known faults and they contributed to the tectonic interpretation of the study areas. 相似文献