共查询到20条相似文献，搜索用时 93 毫秒
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以Visual C＋＋为软件平台，应用ESRI公司提供的COM组件对象MapObjects，结合昆明城市固体废物地理信息查询系统的研制。阐述在MapObjects下应用型城市地理信息系统的二次开发方式及实现过程。对系统选择开发方式、系统总体结构、系统开发结构和建立系统数据库等做了详细叙述，简要介绍了系统实现的主要功能。并给出了部分功能的具体实现方法。 相似文献
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介绍了用于遥感教学的微机遥感图像处理系统的设计,以及Ｃ＋＋语言的实现方法,为辅助遥感教学提供了一个比较好的途径。 相似文献
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针埘GDI＋绘制复杂线状符号存在符号不可编辑与遮捎等问题,设计了一种可编辑的复杂线状符号的组织方法,该方法将复杂线状符号分解为实线、虚线和点线蔓种基本单元,进而设计了基于这一种基本单元的复杂线状符号参数描述方法,解决了GDI＋绘制复杂线状符号存在符号不可编辑与遮挡等问题。采用C#实现了可编辑线状符弓库的设计与开发．建立了1：10000地形图符号库。最后,对本文方法与GDI＋方法的绘制效率进行了比较试验。试验表明本文方法不仅解决了GDI＋绘制复杂线状符号存在符号不可编辑与遮挡等问题．并且绘制效率也明显优于GDI＋方法． 相似文献
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用VC＋＋在制图软件中实现AutoCAD的夹点编辑功能 总被引：2，自引：0，他引：2
本文分析了AutoCAD夹点编辑功能的机理，并详细阐述了如何用VC＋＋OOP方法在制图软件中实现此项功能。 相似文献
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西文以徕卡（TC－307）全站仪为例介绍在Windows环境下用VC＋＋实现全站仪与计算机的串口数据通信。 相似文献
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《制图学和地理信息科学》2013,40(2):129-138
We examine some benefits of using the medial axis as a centerline for rivers and lakes. One benefit, automatic centerline generation, has been used for many years. We show that additional benefits can be derived from the geometric relationships between the medial axis and the riverbanks or lakeshores. These include area estimates, association of centerline analysis to banks, and definition of opposite for riverbanks. We also report on our experience at approximating the medial axis with a Voronoi diagram of point sites. 相似文献
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《制图学和地理信息科学》2013,40(2):160-164
Relief models are difficult to symbolize graphically because traditional drafting techniques are not effective on their irregular surfaces. This note presents some of the procedures we employed preparing and symbolizing two models of the state of Vermont, one for tourism, one for classroom instruction. Room lighting, realism, and ease of application determined color selection for the model and its symbols. We created decalcomanias for model symbolization by painting or applying dry-transfer artwork to clear plastic decal film. We then dissolved the decals into the relief surface with dilute acetone. We made customized decal symbols with commercial photo-imageable dry-transfer materials. 相似文献
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DEM matching is a technique to match two surfaces or two DEMs, at different reference frames. It was originally proposed to replace the need of ground control points for absolute orientation of perspective images. This paper examines DEM matching for precise mapping of pushbroom images without ground control points. We proved that DEM matching based on 3D similarity transformation can be used when model errors are only on the platform’s position and attitude biases. We also proposed how to estimate bias errors and how to update rigorous pushbroom sensor models from DEM matching results. We used a SPOT-5 stereo pair at ground sampling distance of 2.5 m and a reference DEM dataset at grid spacing of 30 m and showed that rigorous pushbroom models with accuracy better than twice of the ground sampling distance both in image and object space have been achieved through DEM matching. We showed further that DEM matching based on 3D similarity transformation may not work for pushbroom images with drift or drift rate errors. We discussed the effects of DEM outliers on DEM matching and automated removal of outliers. The major contribution of this paper is that we validate DEM matching, theoretically and experimentally, for estimating position and attitude biases and for establishing rigorous sensor models for pushbroom images. 相似文献
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利用二元关系和粗糙集的一些性质来研究GIS实体之间关系,发现在基于二元关系的广义近似空间下GIS实体的前继领域、后继领域算子、上、下继领域包含了比它自身更广的一个集合定义。同样基于粗糙集,我们发现二元关系GIS实体的上、下近似比Pawlark粗糙集的定义更广泛。在二元关系的广义近似空间下,一个GIS单点集的上近似等于它的前继领域,同样等于它后继领域的逆。 相似文献
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David O'Sullivan Mark Gahegan Daniel J. Exeter Benjamin Adams 《Transactions in GIS》2020,24(4):967-1000
This article describes two spatially explicit models created to allow experimentation with different societal responses to the COVID‐19 pandemic. We outline the work to date on modeling spatially explicit infective diseases and show that there are gaps that remain important to fill. We demonstrate how geographical regions, rather than a single, national approach, are likely to lead to better outcomes for the population. We provide a full account of how our models function, and how they can be used to explore many different aspects of contagion, including: experimenting with different lockdown measures, with connectivity between places, with the tracing of disease clusters, and the use of improved contact tracing and isolation. We provide comprehensive results showing the use of these models in given scenarios, and conclude that explicitly regionalized models for mitigation provide significant advantages over a “one‐size‐fits‐all” approach. We have made our models, and their data, publicly available for others to use in their own locales, with the hope of providing the tools needed for geographers to have a voice during this difficult time. 相似文献
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本文研究最冷目标地物替代法计算Jason-2微波辐射计JMR年度漂移。针对Jason-2卫星微波辐射计(JMR),利用微波辐射计传输模型,建立JMR 3个通道的全球最低亮温观测值的理论计算模型,模拟其3通道全球地物观测最冷亮温;基于2008年—2012年Jason-2地球物理数据(GDR)产品中全球对地观测亮温序列和模型计算的最冷亮温,建立亮温序列的最小观测亮温统计模型,查找全球地物观测最冷亮温序列;根据地物年度变化特性,建立光谱分析模型,去除最冷亮温序列的年度谐波;去除年度谐波后,采用线性拟合的方法外推最冷亮温序列的理论最小值,并据此计算Jason-2微波辐射计仪器的年度漂移量。 相似文献
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Automated mapping of Hammond's landforms 总被引：2，自引：0，他引：2
We automated a method for mapping Hammond's landforms over large landscapes using digital elevation data. We compared our results against Hammond's published landform maps, derived using manual interpretation procedures. We found general agreement in landform patterns mapped by the manual and the automated approaches, and very close agreement in characterization of local topographic relief. The two approaches produced different interpretations of intermediate landforms, which relied upon quantification of the proportion of landscape having gently sloping terrain. This type of computation is more efficiently and consistently applied by computer than human. Today's ready access to digital data and computerized geospatial technology provides a good foundation for mapping terrain features, but the mapping criteria guiding manual techniques in the past may not be appropriate for automated approaches. We suggest that future efforts center on the advantages offered by digital advancements in refining an approach to better characterize complex landforms. 相似文献
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Joanna Zawadzka Ron Corstanje Jim Harris Ian Truckell 《International Journal of Digital Earth》2020,13(8):899-914
ABSTRACT We propose a method for spatial downscaling of Landsat 8-derived LST maps from 100(30?m) resolution down to 2–4?m with the use of the Multiple Adaptive Regression Splines (MARS) models coupled with very high resolution auxiliary data derived from hyperspectral aerial imagery and large-scale topographic maps. We applied the method to four Landsat 8 scenes, two collected in summer and two in winter, for three British towns collectively representing a variety of urban form. We used several spectral indices as well as fractional coverage of water and paved surfaces as LST predictors, and applied a novel method for the correction of temporal mismatch between spectral indices derived from aerial and satellite imagery captured at different dates, allowing for the application of the downscaling method for multiple dates without the need for repeating the aerial survey. Our results suggest that the method performed well for the summer dates, achieving RMSE of 1.40–1.83?K prior to and 0.76–1.21?K after correction for residuals. We conclude that the MARS models, by addressing the non-linear relationship of LST at coarse and fine spatial resolutions, can be successfully applied to produce high resolution LST maps suitable for studies of urban thermal environment at local scales. 相似文献