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1.
Spatial data analysis (SDA) tools to efficiently handle and explore spatial data have become readily available. Although these SDA tools have their own strengths and purposes, they suffer from limited support in terms of a development environment offering easy customization and high extensibility, a strength of open source software. This article presents a standalone software package for SDA in a geographic information system (GIS) environment, called Spatial Analysis using ArcGIS Engine and R (SAAR), which provides an integrated GIS and SDA environment. A set of SDA tools in SAAR utilizes functions in R using R.NET, while other tools were developed in .NET independent of R. SAAR provides an efficient working environment for both general and advanced GIS users. For general GIS users with limited programming skills, SAAR furnishes advanced SDA tools in a popular ArcGIS environment with graphical user interfaces. For advanced GIS users, SAAR offers an extensible GIS platform to help them customize and implement SDA functions with relatively little development effort. This article demonstrates some functionalities of SAAR using census data for Texas counties.  相似文献   

2.
Loose programming enables analysts to program with concepts instead of procedural code. Data transformations are left underspecified, leaving out procedural details and exploiting knowledge about the applicability of functions to data types. To synthesize workflows of high quality for a geo‐analytical task, the semantic type system needs to reflect knowledge of geographic information systems (GIS) at a level that is deep enough to capture geo‐analytical concepts and intentions, yet shallow enough to generalize over GIS implementations. Recently, core concepts of spatial information and related geo‐analytical concepts were proposed as a way to add the required abstraction level to current geodata models. The core concept data types (CCD) ontology is a semantic type system that can be used to constrain GIS functions for workflow synthesis. However, to date, it is unknown what gain in precision and workflow quality can be expected. In this article we synthesize workflows by annotating GIS tools with these types, specifying a range of common analytical tasks taken from an urban livability scenario. We measure the quality of automatically synthesized workflows against a benchmark generated from common data types. Results show that CCD concepts significantly improve the precision of workflow synthesis.  相似文献   

3.
4.
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   

5.
A Geographical Information System (GIS)‐based approach was developed for the identification of vulnerabilities and the measurement of risks associated with contamination of food systems with biological agents. In this research work, a tight integration of ArcGIS with the Arena simulation tool has been implemented. Arena was used to simulate and track contamination in a food distribution network and transmit the time dependent information to GIS. ArcGIS was employed to provide the primary user interface, process network data, and visualize the results. In addition, the GIS, through its powerful capabilities to process spatial data, could allow decision‐ makers to quickly determine the potential impact of a contamination event, at any stage, as a function of both time and geography. Two contamination scenarios along the farm‐to‐fork chain were examined to show the geographic zone and the proportion of the population affected by the contamination. A constraint Voronoi data structure was developed to define influence zones (these were color coded according to a dynamic risk index), to identify those areas that are at greatest immediate risk as time progresses, and to estimate the population affected by these contamination events. This approach thus appears to have general application to many GIS‐based risk assessment problems.  相似文献   

6.
This research proposes a method for capturing “relatedness between geographical entities” based on the co‐occurrences of their names on web pages. The basic assumption is that a higher count of co‐occurrences of two geographical places implies a stronger relatedness between them. The spatial structure of China at the provincial level is explored from the co‐occurrences of two provincial units in one document, extracted by a web information retrieval engine. Analysis on the co‐occurrences and topological distances between all pairs of provinces indicates that: (1) spatially close provinces generally have similar co‐occurrence patterns; (2) the frequency of co‐occurrences exhibits a power law distance decay effect with the exponent of 0.2; and (3) the co‐occurrence matrix can be used to capture the similarity/linkage between neighboring provinces and fed into a regionalization method to examine the spatial organization of China. The proposed method provides a promising approach to extracting valuable geographical information from massive web pages.  相似文献   

7.
空间信息支持下的电子政务及其展望   总被引:18,自引:6,他引:12  
张家庆 《测绘科学》2003,28(1):21-23
我国电子政务建设正在成为国民经济和社会其他领域信息化的先行者。政府的大量信息与空间位置有关 ,作为一个战略措施 ,空间数据基础设施已经被列为家国信息化建设的重点任务之一。从四个方面阐述了空间数据在电子政务建设中的基础作用。尽管现代GIS提供了许多基于数据的高级分析功能 ,以空间数据承载各种专业数据并实现其可视化是GIS的最基本功能 ,通过这种看来似乎寻常的信息查询服务 ,它所启动的用户视觉与神经器官的内在联想能力 ,及其对分布图形的记忆、分析与推演作用 ,远远超过了可视化自身所提供的直接效果。而在这种简单显示的背后 ,大型GIS潜藏着十分复杂的空间数据的组织与管理调度技术  相似文献   

8.
Blogs, micro‐blogs and online forums underpin a more interconnected world. People communicate ever more and are increasingly keen to explain and illustrate their lives; showing where they are and what they are doing. Desktop, online and mobile mapping landscapes have never been as rich or diverse yet this challenges cartography to adapt and remain relevant in the modern mapping world. We explore the spatial expression and potential value of micro‐blogging and Twitter as a social networking tool. Examples of “twitter maps” are reviewed that leverage the Twitter API and online map services to locate some component of the “tweet”. Scope, function and design are illustrated through development of two proof‐of‐concept map mashups that support collaborative real‐time mapping and the organisation and display of information for mass user events. Through the experiments in using and organising data in this way we demonstrate the value of “cartoblography”– a framework for mapping the spatial context of micro‐blogging.  相似文献   

9.
The research community of Geographic Information Systems and Science (GIS) has been growing rapidly during the last two decades. Little attention has been paid to understanding its geography, structure and evolution. Taking a new organizational perspective, this article aims to fill the knowledge gap by analyzing collaboration and citation networks between GIS research organizations, including academic institutions, government agencies, businesses, and others. These two networks are analyzed in geographical and bibliographical spaces, respectively, to discover characteristic distributions and structures. The results show an uneven geographic distribution of GIS research organizations, and clustered spatial interactions between them. Both collaboration and citation networks exhibit typical “scale‐free” structures, which came into being around the year 2000 and have remained to the present. Further, the GIS research community is composed of 11 cohesive sub‐groups, with each having a clear hub‐spoke structure and a few highly connected organizations as leaders. These results shed light on the overall picture of the GIS research community, and offer a reference system that stimulates further exploration.  相似文献   

10.
空间信息自然语言查询接口的研究与应用   总被引:7,自引:0,他引:7  
提出了空间信息自然语言查询接口(SINLQI),并讨论了基于E—R语义词典的建立、中文分词、查询文法规则及其应用领域等主要问题。  相似文献   

11.
This article attempts to describe the role of tessellated models of space within the discipline of geographic information systems (GIS)—a speciality coming largely out of geography and land surveying, where there was a strong need to represent information about the land’s surface within a computer system rather than on the original paper maps. We look at some of the basic operations in GIS, including dynamic and kinetic applications. We examine issues of topology and data structures and produce a tessellation model that may be widely applied both to traditional “object” and “field” data types. Based on this framework, it can be argued that tessellation models are fundamental to our understanding and processing of geographical space, and provide a coherent framework for understanding the “space” in which we exist. This first article examines static structures, and a subsequent article looks at “change”—what happens when things move.  相似文献   

12.
Advances in computer technologies have improved the quality of maps, making map comparison and analysis easier, but uncertainty and error still exist in GIS when overlaying geographic data with multiple or unknown confidence levels. The goals of this research are to review current geospatial uncertainty literature, present the Error‐Band Geometry Model (EBGM) for classifying the size and shape of spatial confidence intervals for vector GIS data, and to analyze the interpretability of the model by looking at how people use metadata to classify the uncertainty of geographic objects. The results from this research are positive and provide important insight into how people interpret maps and geographic data. They suggest that uncertainty is more easily interpreted for well defined point data and GPS data. When data is poorly defined, people are unable to determine an approach to model uncertainty and generate error‐bands. There is potential for using the EBGM to aid in the development of a GIS tool that can help individuals parameterize and model spatial confidence intervals, but more research is needed to refine the process by which people use the decision tree. A series of guiding questions or an “uncertainty wizard” tool that helps one select an uncertainty modeling approach might improve the way people apply this model to real‐world applications.  相似文献   

13.
TeaExplorer Pro是功能强大的三维地理信息平台,其特点是以三维的形式集成与管理多数据源空间数据,并具有三维空间分析功能,ArcGIS是目前开发二维地理信息系统的主流平台,本文提出了将二者有机结合,利用TerraExplorer Pro和ArcGIS Engine组件构建三维GIS系统的原理和方法。  相似文献   

14.
This article presents two decision support plug‐ins in free GIS software: ArcGIS Explorer Desktop. The ubiquitous WebGIS Analysis Toolkit for Extensive Resources (uWATER) focuses on providing GIS analysis functions: spatial and attribute queries in the public services tool for users with limited access to commercial GIS software. The interface of uWATER is general enough to support decision‐making in numerous management issues in natural resources, economics and agriculture. The uWATER‐Pumping Assessment (uWATER‐PA) toolkit, on the other hand, is an extended package targeting the specific environmental issue of groundwater pumping impacts. The uWATER‐PA package is an excellent alternative to evaluating complex groundwater pumping assessment issues before investing significant time, labor, and funds in monitoring and detailed scientific study. It incorporates simulation of the physics of groundwater flow and user interaction into GIS software. A graphical user interface makes both data entry and interpretation of results intuitive to non‐technical individuals. Results are presented as colored drawdown maps and can be saved in GIS format for future dissemination. The impact of drawdown on existing wells can be characterized and mapped, through the use of uWATER's spatial query capabilities and the drawdown maps generated by uWATER‐PA.  相似文献   

15.
基于ArcGIS Server的城市规划管理信息系统设计   总被引:5,自引:0,他引:5  
ArcGIS Server是ESRI在ArcGIS 9.x系列产品中推出的一个创建企业级GIS应用的平台,它的出现使得分布式GIS应用进入到一个新的领域。本系统基于ArcGIS Server 9.2 Java ADF,根据城市规划管理信息系统的特征及其数据库特点,设计实现了图文一体化流转,以及制图、空间分析和地理编码等高级GIS功能。  相似文献   

16.
地理国情普查是摸清我国国情、国力的重要基础性工作,GIS技术对空间数据的采集、处理、管理以及特有的空间分析能力使其在地理国情普查工作中起到了重要的作用,ArcGIS软件是其中重要的组成部分。本文主要探讨了ArcGIS软件在地表覆盖、地理国情要素采集、遥感解译样本制作和元数据制作方面的应用以及在此过程中需要注意的问题,为以后更广泛地应用提供技术支撑。  相似文献   

17.
Querying geographical information systems has been recognized as a difficult task for non‐expert users. Furthermore, user queries are often characterized by semantic aspects not directly managed by traditional spatial databases or GIS. Examples of such semantic geospatial queries are the use of implicit spatial relations between objects, or the reference of domain concepts not explicitly represented in data. To handle such queries, we envisage a system that translates natural language queries into spatial SQL statements on a database, thus improving standard GIS with new semantic capabilities. Within this general objective, the contribution of this article is to introduce a methodology to handle semantic geospatial queries issued over a spatial database. This approach captures semantics from an ontology built upon the spatial database and enriched by domain concepts and properties specifically defined to represent the localization of objects. Some examples of the use of the methodology in the urban domain are presented.  相似文献   

18.
ArcGIS Server是ESRI在ArcGIS 9.0系列产品中推出的一个创建企业级GIS应用的平台。它的出现使得分布式GIS应用进入到一个新的领域,不仅仅是数据的共享,而且高级的GIS功能如制图、空间分析和地理编码、多用户编辑等也能够通过Internet/Intranet为普通用户所拥有。文中介绍了相关的概念并分析了ArcGIS Server的体系结构,在此基础上通过实例展示了基于ArcGIS Server构建分布式GIS应用的可行性。  相似文献   

19.
由于台风灾害危险性评估是一个复杂的多源信息综合分析的过程,借助功能强大、操作简便和显示直观的ArcGIS作为开发平台,开发了台风灾害危险性评估系统,实现了台风灾害危险性评估的可视化,发挥GIS强大的空间信息可视化管理和分析功能,为台风防灾减灾提供决策服务.  相似文献   

20.
A traditional knowledge “Iñupiaq Web GIS”, based on a five‐year study and containing observations and environmental knowledge of Iñupiat communities indigenous to Arctic Alaska, was incorporated into a Web‐based platform. The website, “Arctic Cultural Cartography,” was created to be an open portal through which the password‐protected “Iñupiaq Web GIS” could be accessed. We discuss the process of developing the web GIS including the incorporation of user‐friendly features such as links to interactive maps, video clips of interviews, discussion boards, and the integration of popular web interfaces such as Facebook. We also discuss short‐ and long‐term goals for the further development of the GIS, its potential as a sustainable, participatory online database for sharing pertinent ecological knowledge, and challenges in achieving optimal community involvement given constraints imposed by remote locations with limited bandwidth.  相似文献   

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