Building Temporal Topology in a GIS Database to Study the Land‐Use Changes in a Rural‐Urban Environment

This article addresses the issue of linking temporal and spatial information into a GIS database structure to investigate the land‐use changes in a rural‐urban region over a thirty‐five‐year period. More specifically, it describes the application of a programming package developed to build temporal topology in an historical land‐use GIS database to efficiently perform spatiotemporal queries. The program was created within the MapInfo environment using MapBasic language. Different types of information, such as the rate of change, the relationship between the change of land use and zoning regulations, and land‐use succession were extracted from the database. A user‐friendly interface was also developed to easily address spatiotemporal queries to the database. This approach represents a flexible and performing tool for scientists and planners who need to efficiently capture essential spatiotemporal information required for geographical inquiry and decision‐making.     

XML Web Service‐based development model for Internet GIS applications

Most of the current Internet Geographic Information System (GIS) applications cannot be shared and are not interoperable because of their heterogeneous environments. With the growth of Internet GIS, many difficulties have occurred in integrating GIS components because of their diversity. The main objective of this study is to suggest a new development model for dynamic and interoperable Internet GIS applications. The model is based mainly on the dynamic integration of Internet GIS components by applying Extensible Markup Language (XML), XML Web Service, Geography Markup Language (GML), and Scalable Vector Graphics (SVG), etc. The relevant technologies of Internet GIS were reviewed thoroughly, and then a new model was designed. During the design of the new model, typical examples of GIS Web Service components were suggested, together with practical structures for applications using these components. Six examples of components and four types of applications were suggested, and they were experimentally implemented for model validation and improvement. The suggested model and components will enable easier and more rapid development of Internet GIS applications through the dynamic integration of distributed GIS components. Users will be able to avoid redundancy and consequently reduce both cost and time during each GIS project.     

中国南极地理信息系统的设计及其在互联网上的实现

利用GeoStar地理信息系统基础平台 ,结合我国近 2 0年来的南极考察测绘资料 ,建立了中国南极地理信息系统 ,并在互联网上发布。本文简述了该系统的设计思想和基本功能 ,在此基础上 ,对其今后更好地为我国南极考察、科研和管理提供服务作了展望。     

GIS and Field‐Based Spatiotemporal Analysis for Evaluation of Paleo–Ice Sheet Simulations*

Reconstructing paleo–ice sheets is significant for paleoclimate reconstructions and evaluations of sea level low stands. Accurate reconstructions of paleo–ice sheet dimensions and dynamics necessitate the combination of field evidence and process modeling. In this study, a GIS‐based technique was developed to quantitatively assess model output against geomorphic data. However, implementation of this technique is not straightforward and requires consideration of time‐space relationships, data representation, resolution, and analytical design. Combined use of two software tools holds considerable promise for the use, application, and interpretation of refined ice sheet models.     

GIS‐based multicriteria decision analysis: a survey of the literature

The integration of GIS and multicriteria decision analysis has attracted significant interest over the last 15 years or so. This paper surveys the GIS‐based multicriteria decision analysis (GIS‐MCDA) approaches using a literature review and classification of articles from 1990 to 2004. An electronic search indicated that over 300 articles appeared in refereed journals. The paper provides taxonomy of those articles and identifies trends and developments in GIS‐MCDA.     

基于企业服务总线的网格GIS集成研究

在面向服务的分布计算架构中,企业服务总线(ESB)提供了服务间智能化集成、管理、中介和交互功能。在利用网格架构的面向服务体系结构中,总结如何利用ESB灵活、开放的集成异构多源的GIS平台和数据源。整体架构基于OGSA,服务集成采用ESB,网格门户和实际GIS平台通过ESB连接,形成基于总线消息驱动的智能化服务集成网格系统。该系统将在Internet平台上广泛互联现有的GIS资源,实现GIS"单系统映射"。通过细粒度服务搭建和配置,生成GIS实例,直接而简单地满足具体的业务需求。     

A Local Example of Land‐Use Change: Southern Illinois—1807, 1938, and 1993*

This article provides an analysis of a wetland site in southern Illinois from presettlement to the present. The study area is part of the Cache River‐Cypress Creek Wetland, which has international importance, as recognized by the Ramsar Convention on Wetlands. Land‐cover data for 1807, 1938, and 1993 were created and analyzed with a geographic information system (GIS). Land‐use change by topographic setting (uplands, transitional, and bottomlands) and soil productivity was quantified and studied. Interviews with local experts informed this analysis. Results illustrate the complexity of environmental change and its driving forces. First, notable forest and swamp acreage was converted to cropland between 1807 and 1938 and, to a lesser degree, from 1938 to 1993. Second, there were land‐use variations by topographic region. Between 1807 and 1938, the largest transformation occurred in the uplands, with substantial acreage converted from forest to cropland. Between 1938 and 1993, however, agriculture decreased in the upland areas as hilly areas reverted to forest cover. At the same time, agriculture expanded in the bottomlands as this land was drained for farming. Third, there are interesting patterns within these categories of land‐use change, as soil productivity is an indicator of what lands were taken out of cropland and converted back to grassland and forest.     

Pre‐Glacial Landform Inheritance in a Glaciated Shield Landscape

We seek to quantify glacial erosion in a low relief shield landscape in northern Sweden. We use GIS analyses of digital elevation models and field mapping of glacial erosion indicators to explore the geomorphology of three granite areas with the same sets of landforms and of similar relative relief, but with different degrees of glacial streamlining. Area 1, the Parkajoki district, shows no streamlining and so is a type area for negligible glacial erosion. Parkajoki retains many delicate pre‐glacial features, including tors and saprolites with exposure histories of over 1 Myr. Area 2 shows the onset of significant glacial erosion, with the development of glacially streamlined bedrock hills. Area 3 shows extensive glacial streamlining and the development of hill forms such as large crag and tails and roches moutonnées. Preservation of old landforms is almost complete in Area 1, due to repeated covers of cold‐based, non‐erosive ice. In Area 2, streamlined hills appear but sheet joint patterns indicate that the lateral erosion of granite domes needed to form flanking cliffs and to give a streamlined appearance is only of the order of a few tens of metres. The inheritance of large‐scale, pre‐glacial landforms, notably structurally controlled bedrock hills and low relief palaeosurfaces, remains evident even in Area 3, the zone of maximum glacial erosion. Glacial erosion here has been concentrated in valleys, leading to the dissection and loss of area of palaeosurfaces. Semi‐quantitative estimates of glacial erosion on inselbergs and palaeosurfaces and in valleys provide mean totals for glacial erosion of 8 ± 8 m in Area 1 and 27 ± 11 m in Area 3. These estimates support previous views that glacial erosion depths and rates on shields can be low and that pre‐glacial landforms can survive long periods of glaciation, including episodes of wet‐based flow.     

GIS‐based DSS for priority setting in humanitarian mine‐action

Mine contamination is one of the main obstacles to economic recovery and other types of progress in mine‐affected countries. Therefore, the primary goal of humanitarian demining operations is to clear all suspected minefields and restore them so as to make them available for their previous use. The customary financial shortfall results in the need for priority setting in the mine removal process. This paper describes and investigates a new approach to priority setting within mine action, with the introduction of a hierarchic GIS‐based decision support system (DSS). The proposed DSS is aimed at determining the objective priorities required to reduce the risks stemming from mine contamination. DSS is based on a combination of GIS analysis and a multicriteria method in order to enable efficacious mine action management, namely setting humanitarian demining priorities in order to optimally reduce the risk caused by mines. GIS is outlined as a powerful tool for the generation of aggregated information used in multicriteria analysis, as is the link between hierarchic decision levels in the proposed DSS. The results of a demonstration of the proposed GIS‐based DSS on mine‐affected water resources in Croatia are supplied.     

GIS research to address tensions in geography

The rise of Geographic Information Systems (GIS) technologies has been producing powerful tools for spatial data processing, management, analysis, modeling, and visualization. While supporting many tasks, GIS technologies have evoked new thinking and advanced intellectual inquiries in geography. Technological advances in other fields often stimulate new research questions and lead to revolutionary discoveries. The Hubble telescope revolutionizes our understanding of the universe, and 3D digital microscopes transform our knowledge of the coordination among biological, neurological, and physiological systems in living organisms. Can GIS claim similar revolutionary effects on geography? The answer is much up for debate. With GIS technologies, geographic studies can explore a broader extent across multiple scales in space and time and tackle problems through increasingly complex spatial statistics, visual analytics, computation, simulation, machine learning, and artificial intelligence. Both the Hubble telescope and 3D digital microscope were built based on scientific research that subserves the technological advances for inquiries into space and life systems. Likewise, GIScience research innovates GIS methods that enable novel geographic investigations and therefore contribute to geographic knowledge production. For the sake of simplicity, the term GIS used here represents both GIScience and GIS technologies. This essay attempts to clarify the intellectual contributions of GIS to geography on the following two questions: (1) What novel geographic thinking is driven by GIS? (2) How may GIS provoke new geographic inquiries and knowledge? Building on Nystuen's notion of four tensions that trigger geographic questions, the essay discusses how GIS innovations mediate historical tension, space‐time tension, dimensional tension and scale tensions.     

“面向区域”的GIS控件的设计与使用

本文提出了一个“面向区域”GIS控件的概念———即以特定的地理区域为对象,将基础地理信息连同有关的GIS功能操作融合为一个可重用的程序模块,以Microsoft的COM(即“组件对象模型”)技术为基础,组织为“GIS化”的ActiveX控件。这种GIS控件,将面向对象技术中的“对象”扩展到了整个特定的地理区域空间,其核心思想是不仅封装了GIS的数据模型,必要的功能操作,而且封装了所有的基础地理信息。由于省去了对空间数据的处理,因而这种GIS控件可被广大非GIS专业的信息系统开发者灵活、简便地用于各种管理信息系统、办公自动化系统和决策支持系统的GIS功能扩充,也可用于构建一般的地理信息系统,因而有利于GIS技术应用的普及。文章最后给出了有关陕西省的应用实例     

Spatial Ecology of Pre –Euro‐American Fires in a Southern Rocky Mountain Subalpine Forest Landscape

Natural disturbances such as fires have been widely studied, but less is known about their spatial ecology than about other aspects of them. We reconstructed and mapped pre–Euro‐American fire history in a subalpine forest landscape in southeastern Wyoming, and analyzed the fires using GIS. Mean fire interval varies little with topography (elevation, aspect, slope) and is spatially autocorrelated at distances of at least 2 km. Fires often spread downslope, and spread more than expected from the north and south and less than expected from the west, under the influence of particular synoptic climatic conditions. The landscape of 1868 a.d., at the time of Euro‐American settlement, was strongly influenced by fires. However, it contained large patches of connected forest and few high‐contrast edges, unlike the modern landscape, which is fragmented by industrial forestry and roads. The spatial ecology of the natural fire regime may be a useful guide for management.     

Evaluating the Geographic in GIS

Despite several decades of discussion and debate around the role of GIS in the discipline of Geography, it would be a stretch to argue that GIS has not irreversibly altered the discipline, both in the scope of research and teaching as well as in the wider imagination of a general public. However, it remains a challenge to incorporate the range of geographic knowledge, born of a diversity of modalities, into operational insights and analytical pre‐conditions in a GIS. To be certain, some irreconcilability between GIS and geographical inquiry is to be expected, epistemologically speaking. In what follows, we consider what might be meant by a shift to geographic analysis as scholars from disciplines in the humanities and social sciences turn to GIS as a method of observation, interpretation, analysis, and representation. In this context, we engage in a thought experiment and offer some commentary, fixing the notion of information system, while opening the geographic in GIS to more variable understanding. The point is to pursue greater development of GIS theory and method, encompassing, while not reducing, scientific, social scientific, and humanities research.     

Exploring potential human activities in physical and virtual spaces: a spatio‐temporal GIS approach

Today, the opportunity for potential human activity has gone beyond physical space to virtual space. Based on a proposed conceptual framework that models the relationships between physical and virtual spaces, this paper presents an attempt to adjust the space–time prism concept of Hägerstrand's time geography to identify potential activity opportunities in virtual space, focusing on the virtual space access channels available in physical space. A three‐dimensional (3D) spatio‐temporal Geographic Information System (GIS) design has been developed in this research to accommodate the adjusted space–time prism concept to support the representation, visualization, and analysis of potential human activities and interactions in physical and virtual spaces using the prism representation. Following the design, a prototype system has been successfully implemented in a 3D GIS environment. Such a system can provide powerful analytical tools for studies related to potential human activities and applications such as location‐based services (LBS) and accessibility analysis in the information age.     

Getting Away with the Stolen Vehicle: An Investigation of Journey‐after‐Crime*

Analyses of criminals' travel patterns can provide significant suggestions to improve crime management. This study extends the investigation of criminals' travel behavior from journey‐to‐crime to journey‐after‐crime. Moreover, new methods are developed to examine the spatial patterns of location pairs when restricted by the underlying geographical process. The methods are employed to investigate criminals' journey‐after‐auto‐theft in the city of Buffalo, New York. The analyses reveal that auto thieves' trips from vehicle‐theft locations to the corresponding vehicle‐recovery locations are local in nature. The travel distances are significantly shorter than the randomly simulated trips; the travel directions are biased from the random directions as well.     

OpenCIS—Open Source GIS‐based web community information system

Geographic Information System (GIS) technology has many applications and plays a vital role in the majority of the daily operations by government and public administration. However, due to its technical complexity and cost, communities lacking the expertise and resources cannot benefit from this technology. The OpenCIS project, a user‐friendly free Open Source GIS‐based Web Community Information System, seeks to address this issue by bridging the gap between a simple map viewer and full GIS, representing one of the first steps towards the goal of grassroots empowerment through GIS technology.     

动态柔性地物三维模拟理论与方法新探

针对地学动态柔性物体建模,提出GIS流素与柔性体元(GIS Flow Element and Soft Voxel)的概念,作为动态柔性地物的基本模拟单元。当忽略体积时,称为GIS流素(FE);当强调体积时,则称为GIS柔性体元(SV)。GIS流素与柔性体元三维模拟基于计算机图形学中的粒子与元球技术,区别在于GIS流素与柔性体元具有明确的地学意义,并基于地学模型突出反映地学规律。现实世界中,水流、泥沙、雪花、云雾、泥石流、熔岩流、草原等均可用(7)IS流素进行模拟,而构造运动中岩层的挤压、扭曲变形、生物体、树木随风摆动等可用GIS柔性体元进行模拟。该文以水流与土壤模拟为例,论证该方法的应用前景。     

Modelling three‐dimensional geoscientific fields with the Voronoi diagram and its dual

Fields as found in the geosciences have properties that are not usually found in other disciplines: the phenomena studied are often three‐dimensional (3D), they tend to change continuously over time, and the collection of samples to study the phenomena is problematic, which often results in highly anisotropic distributions of samples. In the geographical information system (GIS) community, raster structures (voxels or octrees) are the most popular solutions, but, as we show in this paper, they have shortcomings for modelling and analysing 3D geoscientific fields. As an alternative to using rasters, we propose a new spatial model based on the Voronoi diagram (VD) and its dual the Delaunay tetrahedralisation (DT), and argue that they have many advantages over other tessellations. We discuss the main properties of the 3D VD/DT, present some GIS operations that are greatly simplified when the VD/DT is used, and, to analyse two or more fields, we also present a variant of the map algebra framework where all the operations are performed directly on VDs. The usefulness of this Voronoi‐based spatial model is demonstrated with a series of potential applications.     

无级比例尺GIS多边形倒金字塔模型

提出GIS多边形倒金字塔模型,拓展了模型能够支持的数据结构与适用范围,使其可以应用于普通GIS电子地图中,为采用预生成不同比例尺图面多分辨率表达无极比例尺图形显示技术提供了模型支持,并给出了建模方法,使普通GIS多边形的无极比例尺显示可以依据精度标准进行局部更新和无冗余存储。