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Jason K Blackburn rew Curtis Frances Currin Mujica Farrell Jones Patricia Dorn Rosamond Coates 《Transactions in GIS》2008,12(2):249-265
This article describes a web‐based data entry and GIS‐driven mapping system designed for an ethnographic and entomological survey of Chagas’ disease, an emerging zoonotic disease, and Triatoma dimidiata, a primary vector, in the Los Tuxtlas region of Veracruz, Mexico. To better understand this disease in the region, a collaborative, multi‐disciplinary study was initiated to conduct a spatial investigation of T. dimidiata and a community‐by‐community survey of local perceptions of the disease. In order to facilitate such a collaborative effort the CODES‐GIS was developed. This system allows for (near) real‐time mapping, analyses, disease reporting, and results sharing. CODES‐GIS provides a framework for a research team working in a remote area with limited technology, software, or GIS expertise to benefit from (near) real‐time spatial analyses performed at collaborating institutions. The system is bi‐directional, where field personnel can upload data to the system for field‐based map production. Likewise, laboratory personnel can upload diagnostics data for viewing by field personnel. In this way, the system provides a virtual link between the field and the laboratory to increase the speed at which results are returned to the local community. The CODES‐GIS is described along with a selection of study results. 相似文献
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GIS空间数据具有多源性的特征，为数据综合利用和数据共享带来不便，解决多格式数据源集成一直是近年来GIS应用系统开发中需要解决的重要问题。ARC／INFO软件是当前众多地理信息系统软件中功能最强、市场占有率最高的软件。E00格式作为一种空间数据转换的事实上的标准，对于自主版权的GIS软件MapStore来说，实现两者的数据转换具有重要意义。本文分析了MapStore与ARC／INFO空间数据模型的组织特征，在比较分析的基础上设计了转换方案，并就实现过程中的关键技术进行了论述。 相似文献
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Estimates of solar radiation distribution in urban areas are often limited by the complexity of urban environments. These limitations arise from spatial structures such as buildings and trees that affect spatial and temporal distributions of solar fluxes over urban surfaces. The traditional solar radiation models implemented in GIS can address this problem only partially. They can be adequately used only for 2‐D surfaces such as terrain and rooftops. However, vertical surfaces, such as facades, require a 3‐D approach. This study presents a new 3‐D solar radiation model for urban areas represented by 3‐D city models. The v.sun module implemented in GRASS GIS is based on the existing solar radiation methodology used in the topographic r.sun model with a new capability to process 3‐D vector data representing complex urban environments. The calculation procedure is based on the combined vector‐voxel approach segmenting the 3‐D vector objects to smaller polygon elements according to a voxel data structure of the volume region. The shadowing effects of surrounding objects are considered using a unique shadowing algorithm. The proposed model has been applied to the sample urban area with results showing strong spatial and temporal variations of solar radiation flows over complex urban surfaces. 相似文献
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Volunteered Geographic Information (VGI) has the potential to offer benefits to end‐users over and above those of Professional Geographic Information (PGI). A multi‐methods approach, consisting of participatory observation, focus groups and diary studies, was used to study how VGI and PGI were actually used by a target user group. A theoretical framework of information relevance was used to understand the attributes of information that were most important in relation to the characteristics of the users' activity and their community. The key finding was that the discussion amongst GIS designers should not be whether to choose VGI or PGI as the information data set, but to consider which combination of VGI and PGI relating to different geographic features and task characteristics would best meet the users' needs. VGI is likely to be most relevant to the user when a geographic feature is dynamic rather than static in nature, and can also provide a level of detail that is unlikely to arise through PGI. These findings have implications for how different forms of information are most effective for different usage situations. Above all, a case is presented for the implementation of User Centred Design (UCD) principles when integrating VGI and PGI together in a single mashup‐based product. 相似文献
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电子地图的数据交换(CNSDTF)实现 总被引：4，自引：2，他引：4
电子地图是传统地图的矢量数据格式，由于采用不同的软件平台和不同的数据格式，因此在进行数据交换和数据共享时经常需要进行数据格式的转换。中国《地球空间数据交换格式》标准中给出了矢量数据交换的标准格式，对于GIS应用中的矢量数据交换基本已满足要求，但对于电子地图的交换尚有不足。本文在认真研究了电子地图的一般特征后，提出了电子地图所具备的图形表现属性不同于非图形属性的概念，在不违背标准的基本原则下扩充了现有标准的格式，大大方便了电子地图数据的交换，并且给出了程序实现的简要流程。 相似文献
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Recent developments of the communication technologies in the last years opened a new dimension to Geographical Information Systems and Geoinformation Techno‐logies. This new dimension is mobility. It is simplifying data gathering, processing and presentation independent from the area of application. A new branch, Mobile Geoinformation Technologies, is based on wireless communication systems, mobile personal computers, positioning systems and GIS. There are some proprietary GIS software solutions for mobile or handheld devices available on the market, but they are more focused on data logging tasks than providing full powered GIS support or data processing functions. In this paper, we propose a mobile implementation of the free and easily expandable GRASS GIS software in combination with the GNU/Linux operating system run on handheld devices. This approach supports real time in the field computations, data processing and cooperation of several active mobile clients using wireless networking. 相似文献
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城市大比例尺CAD数据到GIS数据的转换 总被引：1，自引：0，他引：1
CAD数据是城市大比例尺数据中常用的数据格式,但在很多GIS应用,CAD数据格式受到限制,需要进行数据的转换处理。本文以在地理信息公共服务平台建设中应用的城市CAD数据到GIS数据的转换工作为基础,对CAD数据到GIS转换的主要工作流程进行介绍。 相似文献
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The use of cellular automata (CA) has for some time been considered among the most appropriate approaches for modeling land‐use changes. Each cell in a traditional CA model has a state that evolves according to transition rules, taking into consideration its own and its neighbors’ states and characteristics. Here, we present a multi‐label CA model in which a cell may simultaneously have more than one state. The model uses a multi‐label learning method—a multi‐label support vector machine, Rank‐SVM—to define the transition rules. The model was used with a multi‐label land‐use dataset for Luxembourg, built from vector‐based land‐use data using a method presented here. The proposed multi‐label CA model showed promising performance in terms of its ability to capture and model the details and complexities of changes in land‐use patterns. Applied to historical land use data, the proposed model estimated the land use change with an accuracy of 87.2% exact matching and 98.84% when including cells with a misclassification of a single label, which is comparably better than a classical multi‐class model that achieved 83.6%. The multi‐label cellular automata outperformed a model combining CA and artificial neural networks. All model goodness‐of‐fit comparisons were quantified using various performance metrics for predictive models. 相似文献
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BIM的发展为数字城市三维模型提供了更加精确的数据来源,现有研究主要关注BIM空间实体模型向三维表面模型转换,缺少建筑语义信息映射及整体集成方案研究。本文以构成建筑骨架的主要空间构件为研究对象,在参考IFC标准基础上,结合数字城市应用特点设计了具有空间语义一致性的建筑构件信息模型BCM,在此基础上提出建筑信息模型和三维数字城市集成方案。首先,基于CAD图纸开展BIM模型交互式构建,然后,通过空间和语义信息映射将其转换为BCM,并基于ArcGIS Geodatabase建立建筑构件信息库,在三维数字城市场景开展建筑构件信息的集成应用。该方案可实现建筑构件信息与三维数字城市的大规模集成,对推动数字城市向智慧城市发展,进一步开展建筑内外模型集成展示、建筑节能分析、内部设施管理等具有重要价值。 相似文献
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多进制小波在矢量地图数据压缩中的应用 总被引：3，自引：1，他引：3
矢量地图数据压缩在地形环境仿真、制图综合、GIS等研究中具有重要作用。利用多进制小波变换理论和矢量地图数据的特点,提出了基于多进制小波变换的矢量地图数据压缩的模型和方法,并从理论上分析了多进制小波变换与二进制小波变换的相互联系、区别及多进制小波变换所具有的优良特性。在对实际数据试验的基础上,分析了利用多进制小波变换得到的矢量地图数据具有多层次、多细节、能够保持良好形状结构特征的性质。 相似文献
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针对移动GIS应用商业开发组件难以进行自由定制与分发的问题,该文提出一种基于嵌入式Web服务器的Android移动端空间数据离线解决方法,该方法通过在Android设备中移植开源的NanoHTTPD服务器实现了地图瓦片服务和矢量要素服务,并通过编码读取bundle切片数据包和扩展Spatialite空间数据库的方式,解决了切片数据和矢量要素数据的存储,然后利用Webview控件内嵌HTML5页面加Leaflet地图库完成了前端功能实现,并进行了实际应用展示。该方案的实现可节省Android端移动GIS应用开发成本,具有推广意义。 相似文献
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基于组件技术的GIS数据格式转换研究 总被引：4，自引：0，他引：4
多源数据格式之间的转换是目前GIS深入应用遇到的重要问题,本文探讨了不同GIS数据之间的转换问题,提出了以组件技术为基础的数据转换自定义接口开发的思路,保证了数据转换的完整性和安全性,优化了GIS数据从制作到发布的流程。并以MapGIS和GeoMed ia为实例叙述了数据转换实施的过程。 相似文献
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针对当前遥感数据缺乏统一文件格式标准,多源遥感产品的生产使用涉及多种文件格式的现状,在研究多种遥感数据格式及对应库GDAL、HDF4、HDF5的基础上,参考国家气象局的NOAA AVHRR 1B格式标准,利用工厂模式,设计和实现了一个具有统一操作接口的多源遥感数据格式抽象库DFAL,在更高的抽象层次解决了GDAL和HDF4、HDF5库不能一致使用的问题。使用DFAL库进行不同文件格式的读写,专家无需了解这些文件格式的差别,以便从繁杂的遥感数据格式中解放出来,将更多精力投入到遥感科学研究的层面上。在DFAL库的基础上实现了两类常用遥感数据格式Geo TIFF和HDF5之间的转换工具,方便工程应用。DFAL库及转换工具在国家高技术研究发展计划《星机地综合定量遥感系统与应用示范》的多尺度按需定量遥感产品生产系统中进行了应用测试,取得了很好的实际效果,证明了DFAL库稳定性和可用性,并大大减少了多源数据协同使用时多种文件格式读写的工作量。 相似文献
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The multi‐objective land allocation problem is to optimize the selection of land for different uses based on a set of decision objectives. For most applications, a geographical information system (GIS) is either absent or loosely coupled through file exchange. In this article the evolutionary algorithm (EA), a heuristic solution method for optimization problems, is integrated with a raster GIS to form a spatial decision support system (SDSS) for multi‐objective conservation reserve design. The SDSS effectively combines the functions of a GIS for data management, analysis, and visualization, with the optimization capability of the EA; and provides a uniform way to solve conservation reserve design problems with different types of constraints and objectives. The SDSS is demonstrated through application to the creation of conservation reserves in Bolivia to protect 17 endemic mammals. 相似文献
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Much effort has been applied to the study of land use multi‐objective optimization. However, most of these studies have focused on the final land use scenarios in the projected year, without considering how to reach the final optimized land use scenario. To fill this gap, a spatio‐temporal land use multi‐objective optimization (STLU‐MOO) model is innovatively proposed in this research to determine possible spatial land use solutions over time. The STLU‐MOO is an extension of a genetic land use multi‐objective optimization model (LU‐MOO) in which the LU‐MOO is generally carried out in different years, and the solutions at year T will affect the solutions at year T + 1. We used the Wuhan agglomeration (WHA) as our case study area. The STLU‐MOO model was employed separately for the nine cities in the WHA, and social, economic, and environmental objectives have been considered. The success of the experiments in the case study demonstrated the value and novelty of our proposed STLU‐MOO model. In addition, the results also indicated that the objectives considered in the case study were in conflict. According to the results, the optimal land use plan in 2050 can be traced back to 2040, 2030, and 2020, providing a series of Pareto solutions over the years which can provide spatio‐temporal land use multi‐objective optimization solutions to support the land use planning process. 相似文献
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This paper systematically investigates spatially autocorrelated patterns and the behaviour of their associated test statistic
Moran's I in three bounded regular tessellations. These regular tessellations consist of triangles, squares, and hexagons, each of
increasing size (n=64; 256; 1024). These tesselations can be downloaded at http://geo-www.sbs.ohio-state.edu/faculty/tiefelsdorf/regspastruc/
in several GIS formats. The selection of squares is particularly motivated by their use in raster based GIS and remote sensing.
In contrast, because of topological correspondences, the hexagons serve as excellent proxy tessellations for empirical maps
in vector based GIS. For all three tessellations, the distributional characteristics and the feasibility of the normal approximation
are examined for global Moran's I, Moran's I
(k) associated with higher order spatial lags, and local Moran's I
i. A set of eigenvectors can be generated for each tessellation and their spatial patterns can be mapped. These eigenvectors
can be used as proxy variables to overcome spatial autocorrelation in regression models. The particularities and similarities
in the spatial patterns of these eigenvectors are discussed. The results indicate that [i] the normal approximation for Moran's
I is not always feasible; [ii] the three tessellations induce different distributional characteristics of Moran's I, and [iii] different spatial patterns of eigenvectors are associated with the three tessellations.
Received: 2 July 1999 / Accepted: 9 November 1999 相似文献