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1.
Abstract. Research papers at conferences such as EGIS and the International Symposia on Spatial Data Handling address a set of intellectual and scientific questions which go well beyond the limited technical capabilities of current technology in geographical information systems. This paper reviews the topics which might be included in a science of geographical information. Research on these fundamental issues is a better prospect for long-term survival and acceptance in the academy than the development of technical capabilities. This paper reviews the current state of research in a series of key areas and speculates on why progress has been so uneven. The final section of the paper looks to the future and to new areas of significant potential in this area of research.  相似文献   

2.
Abstract

Research on time and data models for Geographical Information Systems (GIS) has focused mainly in the representation of temporal geographical entities and implementation of temporal databases. Many temporal GIS database structures have been proposed but most of them just provide principles, not the recipe for the design. Owing to the manipulation of the large quantity of geographical information and the slow response time, few implementations exist. This paper presents a relational method of storing and retrieving spatial and temporal topologies. Two-level state topologies are proposed: a state topology for a set of geographical entities and a state topology for a single geographical entity.

From a temporal perspective, these two-level state topologies may also be viewed as two-level time topologies: a time topology for all geographical entities in a GIS database and a time topology for a single geographical entity. Based on these state and time topologies, a detailed storage approach for historical geographical information is provided.  相似文献   

3.
4.
Abstract

The space-time Of time geographical framework is a powerful perspective from which to analyse human behaviour. One of the central concepts in this framework is the space-time prism, which models individual accessibility to an environment. In this paper, the derivation and manipulation of space-time prism concepts within a geographical information system (GIS) are discussed. The required system inputs and desired outputs are identified and a generic GIS based procedure is presented Given these basic requirements, issues are discussed which can determine the feasibility of current GIS technology to handle the derivation of space-time prism concepts.  相似文献   

5.
Abstract

Understanding the use and value of geographical information in decision making has been identified as crucial to the further development of geographical information systems and related spatial analysis techniques. Research into the use of geographical information will be through surveys and case studies. A taxonomy for investigating the use of geographical information and its associated value is needed to structure the surveys and case studies. This paper presents an initial attempt at such a taxonomy, intended to support continuing research into the use and value of geographical information. The survey methodology to be supported will be mostly telephone and/or mail questionnaires, and this has influenced the structure of the taxonomy. The goal of this work is to create a taxonomy suitable for use in surveys that will enhance the understanding of the use and value of geographical information in decision making.  相似文献   

6.
Abstract

Practitioners and academics from many fields of study are currently facing numerous issues involving the diffusion of technologies from geographical information systems within their respective professions. This paper has two aims. The first is to report the partial results of a postal survey of selected municipal planning departments in the U.S.A. In measuring trends related to the adoption of computer and geographical information system technologies, the survey focuses on the availability of trained geographical information system and computer literate staff and on alternative means of training existing staff, as well as on the adequacy of collegiate education. The presentation of survey results is used to establish a framework for the principal discussion of this paper. The second part examines the relationship between planning and education in geographical information systems. Parallels within other disciplines and professions are derived. Curricula and training considerations within academic programmes and professional practice are suggested.  相似文献   

7.
Abstract

This paper summarizes the numerous developments in geographical information systems (GIS) in the United Kingdom over the past few years, covering the development of systems, the creation of data bases, the elucidation of user needs, the education and training of staff and the role adopted by government. The review is organized by the different sectors now actively involved in GIS.  相似文献   

8.
Abstract

Attempts have been made by different organizations in India to organize data in order to develop a suitable information system. These attempts were oriented towards specific uses, such as natural resources, data management, thematic mapping and the like. In some attempts software has been developed for some specific purpose. It is not an easy task to develop an information system for a country such as India. Its extent in latitude and longitude is well above average. There are federal and state agencies for the collection of data and the preparation of maps. The geographical information concerning India is available from the following sources: the administrative areas of states, union territories, districts, sub-districts and villages; survey sheets; remote sensing images; aerial photographs; and thematic base maps of the National Atlas and Thematic Mapping Organisation. There are other map series available which have been used for socio-economic mapping. By the end of 1987 the Indian Remote Sensing Satellite will be launched and then remotely-sensed data will be readily available. Considering the geographical bases available in the country, five levels can be identified for developing an information system for India. Some of the thematic maps at 1:1000 000 scale can be used for initiating such a geographical information system.  相似文献   

9.
Abstract

Remotely-sensed image data have long served as a primary source of information for. geographical information systems (GIS), with the transformation of data to information provided by visual image interpretation. Digital image data, in combination with recent advances in computer technology, currently allow visual image interpretation to be realised in a completely digital processing environment. However, it remains desirable to capitalize even further on the potential of digital image data for GIS, through the use of schemes involving automated data processing. The opportunities for, and impediments to, such schemes are considered here with particular reference to the provision of information for natural resource management. It is concluded that further—although foreseeable—developments in both research and technology will be required before fully operational procedures for the automated acquisition of GIS information from image data can be established.  相似文献   

10.
试论地理信息科学   总被引:18,自引:2,他引:16  
杨开忠  沈体雁 《地理研究》1999,18(3):260-266
通过阐述地理信息科学的定义,及其地理学传统和技术驱动机制,论证地理信息科学是地理学信息革命和范式演进的结果,是从信息机理的角度研究地球表层人地关系系统的地理学科,并提出其内容框架和学科体系。  相似文献   

11.
Abstract

This paper describes a framework for the role of geographical information systems (GIS) in the monitoring and management of hazardous waste sites. Compilation of required information, incorporation of existing strategies for waste monitoring, analysis of these data in a GIS environment and the integration of computerized models for transport processes are discussed. Examples for the analysis of spatial data using techniques of cartographic overlay and the implementation of geo-statistical methods on monitoring data are provided from work in progress by the authors. These examples are set in the context of developing a fully integrated monitoring and management system utilizing GIS technology.  相似文献   

12.
Abstract

This paper describes a generic structure model for large numbers of spatially-related images held within a multi-media information system. Applications vary from multi-scale map tilings underlying geographical information system user interfaces to sets of spatially-related visual data held in image form, such as ‘structured walks’ and sets of views with finder maps. The model enables an abstract structure to be soft-configured onto any indexed collection of images and related to standard databases of textual and graphical information at various levels. This is achieved by defining a number of customized ‘image structures’ and providing techniques for their manipulation. Key features of the model are defined in VDM-SL, a formal specification language being standardized by the International Organization for Standardization. The formal definitions are accompanied by explanations in English and by examples. Prototype implementations are described. A glossary of symbols, terms and expressions is given in the Appendix.  相似文献   

13.
Abstract

Many geographical information systems offer the possibility of converting vector data to raster data and using the raster pattern for analysis. This conversion process is already well known and has been used for many years. This paper shows how a selection of eight geographical information systems convert vector test data to a raster pattern. Each system handles this process in its own way, giving results that differ both in number and in the location of assigned raster cells in the raster pattern. The results of the conversions are compared with a desired raster pattern based on five simple principles. Suggestions are made about standardizing the process of conversion for all geographical information systems to make it possible to create and exchange data more safely.  相似文献   

14.
Abstract

Recent changes in information technology offer the opportunity to explore alternative architectures for geographical information systems (GIS) which might better support advanced applications. This paper describes the architecture and implementation of the environmental decision support system (EDSS), a prototype GIS tool kit. The architecture is based on a simple yet powerful systems model using only data collections, views and operations as the basic entity types. The design of the user interface, data management and data analysis within the model are outlined, with particular emphasis on the advanced facilities for which implementation is simplified by the architecture. A prototype applications system, BANKSIA, is also described.  相似文献   

15.
Abstract

The Institute of Terrestrial Ecology (ITE) Digital Cartographic Service provides a range of services to the scientists of ITE (and others) including various techniques within the field of geographical information systems (GIS). This paper discusses work of this type as it is applied to specific ITE projects. The emphasis is very much on GIS applications to ‘real ecological science’ such as the ‘acid water’ problem and the change of forest areas into heathland. Some comments are made on fundamental GIS techniques, their use and limitations. At ITE, GIS applications are growing out of an existing use of digital mapping and remote sensing technologies; they have not purchased a GIS system ‘off the shelf.’  相似文献   

16.
Abstract

Progress in technical database management systems offers alternative strategies for the design and implementation of databases for geographical information systems. Desirable extensions in the user data types and database management are reviewed. A prototype geographical database tool-kit, SIRO-DBMS, which provides some spatial data types and spatial access methods as external attachments to a kernel relational database management system, is described. An ability to fragment a large set of entities into several relations while retaining the ability to search the full set as a logical unit is provided. Implementation of the geometric data types is based on mapping the types of data into a set of attributes of the atomic types supported by the kernel and specifying the relational designs for the set of atomic attributes.  相似文献   

17.
Abstract

The planning and establishment of a geographical information system (GIS) relates to its context and intended use. GIS are a specialized type of information system, typically dealing with spatial data. This paper explores the environment of an envisaged GIS; the information utilization system and the wider object system. The planning and design of a GIS go beyond technical issues; they also have to take behavioural and organizational aspects of the utilization of information into account and contribute to a process of organizational development The paper is in two parts. The first (§ 2) explores salient aspects in the planning and design process, the second ( § 3) suggests some guidance in this task. The suggested approach of strategic choice in planning and establishing a GIS is designed to cope with the prevailing uncertainties in this planning process. It distinguishes between those decisions which have to be taken at once and choices which may be left open for the future.  相似文献   

18.
19.
Abstract

Although biological diversity has emerged in the 1980s as a major scientific and political issue, efforts at scientific assessment have been hampered by the lack of cohesive sets of data. We describe, in concept, a comprehensive national diversity information system, using geographical information system (GIS) techniques to organize existing data and improve spatial aspects of the assessment. One potential GIS analysis, to identify gaps in the network of nature reserves for California, is discussed in greater detail. By employing an information systems approach, available data can be used more effectively and better management strategies can be formulated.  相似文献   

20.
Abstract

The accumulation of geological information in digital form, due to modern exploration methods, has introduced the possibility of applying geographical information system technology to the field of geology. To achieve the benefits in information management and in data analysis and interpretation, however, it will be necessary to develop spatial models and associated data structures which are specifically designed for working in three dimensions. Some progress in this direction has already been demonstrated, with the application of octree spatial subdivision techniques to the storage of uniform volume elements representing mineral properties. By imposing octree tessellations on more precisely-defined geometric data, such as triangulated surfaces and polygon line segments, it may now be possible to combine efficient spatial addressing with topologically-coded boundary representations of geological strata. The development of storage schemes capable of representing such geological boundary models at different scales poses a particular problem, a possible solution to which may be by means of hierarchical classification of the vertices of triangulated surfaces according to shape contribution.  相似文献   

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