基于DEM生成等高线的方法   总被引：2，自引：0，他引：2  

聂欣  李鑫慧  吴良林 《地理空间信息》2009,7(4):85-88

绘制等高线算法，分为等高线确定，等高线短线构成和等高线短线连接。首先确定每条等高线具体高程和等高线条数，根据等高线高程，划分各点所在地势级，找出地势变化处的点，在这些点的附近找出等高线经过处，内插出等高点，再将同一等高线上的两点连接成短线，短线连接是根据同一等高线上的点，高程相等又相互连接，在等高线短线中，找出高程相等，由相同坐标点的短线，将其逐个连接起来，便形成了完整的等高线。  相似文献   

等高线自动内插关键算法     

胡耀锋  林鸿  张鹏程 《测绘科学》2016,41(8):24-27,62

针对现有规则网格法、三角网法、最大角优先原则法、最近距离法等等高线内插算法的局限性,该文结合数字线划图中离散高程点和高程注记的图式表达特点,提出了距离优先算法和综合匹配法;结合等高线节点分布特征,提出了按节点提取算法和按距离提取算法。通过这些算法的组合应用,解决了等高线自动内插的技术难题,并以此算法为基础开发出了一套成熟的软件,通过广州增城地区1 616km~2地形图编绘和日常工作实践,验证了该算法的适应性和先进性。  相似文献   

A numerical study of the string function using a primitive equation ocean model     

R. H. Tyler  R. Käse 《地球物理与天体物理流体动力学》2013,107(1-2):65-83

Abstract

We use results from a primitive-equation ocean numerical model (SCRUM) to test a theoretical 'string function' formulation put forward by Tyler and Käse in another article in this issue. The string function acts as a stream function for the large-scale potential energy flow under the combined beta and topographic effects. The model results verify that large-scale anomalies propagate along the string function contours with a speed correctly given by the cross-string gradient. For anomalies having a scale similar to the Rossby radius, material rates of change in the layer mass following the string velocity are balanced by material rates of change in relative vorticity following the flow velocity. It is shown that large-amplitude anomalies can be generated when wind stress is resonant with the string function configuration.  相似文献   

Obtaining High Fidelity Triangular Regular Network from Only DEM Points     

C. Worth   《The Cartographic journal》2013,50(2):150-156

Abstract

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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   

基于不同插值方法的地下水等值线图绘制研究     

艾强 《地下水》2012,(3):24-26,49

将SURFER软件应用到地下水位等值线图绘制中,并以希尼尔水库为例,研究采用不同插值方法下SURFER软件绘制等值线图的差异,提出了不同插值方法的适用范围。  相似文献   

一种基于面向对象辅以DSM的建筑物提取方法     

王俊博  金琦  杨国东  张旭晴  詹国旗  邵鹏 《世界地质》2018,37(4):1258-1264

基于面向对象技术并辅以DSN的方法来快速提取建筑物信息,从LiDAR点云数据生成的DSM中提取到坡度信息,并根据对象的高度信息来提取到建筑物的大致轮廓,然后分割建筑物轮廓外的对象,依据已分建筑物对象的空间信息、形状信息及光谱信息来优化建筑物轮廓。实验结果表明,提取到的对象的正确率为97. 9%,完整率为96. 4%。  相似文献   

侧视地图中建筑物轮廓线提取的三维城市模型法     

朱园媛  朱庆  张叶廷  彭明军  高山 《测绘学报》2015,44(9):1036-1041

针对城市侧视地图上建筑物轮廓线主要依靠人工交互提取,成本高昂、效率低下且精细度和准确度有限的问题,提出了一种任意视角侧视地图中建筑物轮廓线的自动提取方法。采用深度缓冲区分割算法获取单个建筑物对象的颜色缓冲区,顾及了存在建筑群的情况和建筑物密集区域的遮挡问题,再基于颜色缓冲区追踪建筑物轮廓线。为了保持遮挡一致性且便于匹配提取出的矢量轮廓线与栅格侧视地图,本文还提出了基于投影空间分块加载三维城市模型的方法。最后,以武汉市典型三维城市模型数据为例,证明了该方法的有效性和可靠性。  相似文献   

Mapping bathymetry based on waterlines observed from low altitude Helikite remote sensing platform     

JO Young-Heon  SHA Jin  KWON Jae-Il  JUN Kicheon  PARK Jinku 《海洋学报(英文版)》2015,34(9):110-116

Mapping shoreline changes along coastal regions is critically important in monitoring continuously rising sea surface heights due to climate change and frequent severe storms. Thus, it is especially important if the region has very high tidal ranges over very gentle tidal flats, which is a very vulnerable region. Although the various remote sensing platforms can be used to map shoreline changes, the spatial and temporal resolutions are not enough to obtain it for a short time. Accordingly, in this study we introduce the newly developed low altitude Helikite remote sensing platform to achieve much better resolutions of shorelines and a bathymetry. The Helikite stands for Helium balloon and Kite, which is a kind of aerial platform that uses the advantages of both a Helium balloon and a kite. Field experiments were conducted in the Jaebu Island, off the coast of the west Korean Peninsula in January 29, 2011. In order to extract shorelines from the consecutive images taken by the low altitude Helikite remote sensing platform, active contours without edges (ACWE) is used. Edges or boundaries exist primarily on places between one type of objective and the other. Since the hydrodynamic pressure has an effect everywhere, the locations of the waterlines can be the isobath lines. We could map several waterlines, which would enable us to complete a local bathymetry map ranges from 35 to 60 cm depth. The error resulting from applying ACWE algorithm to the imagery to determine the waterline is approximately less than 1 m. Therefore, it is very unique way to obtain such high resolutions of bathymetry with high accuracy for the regions of extremely high tidal ranges for a short time.  相似文献   

基于CASS的土石方多种计算方法与比较   总被引：1，自引：0，他引：1  

李建飞  秦岩宾  齐中举 《测绘工程》2012,21(3):78-80

对传统常规计算土方量的具体方法、算法原理、应用范围、计算步骤等进行对比分析,对其注意问题进行探讨,研究并总结常规方法的优缺点.  相似文献   

一种由等高线构建DEM的新方法   总被引：3，自引：0，他引：3  

宋敦江  岳天祥  杜正平 《武汉大学学报(信息科学版)》2012,37(4):472-476

基于HASM,提出了一种由等高线建立DEM的新方法HASM-OC。HASM—OC方法保证地形曲面的整体光滑性,保证DEM最大程度上忠实于原始等高线数据。实际等高线案例结果表明,HASM—OC方法与基于薄板样条原理的Hutchinson方法的DEM模拟结果及其回放的等高线差相比,前者比后者保留更多的地形特征信息,前者的回放等高线比后者回放等高线更忠实于原始数据。  相似文献