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1.
Abstract

Appropriate technology (AT) has become an integral part of the programmes for decentralized regional development in the Third World. ‘Appropriate’ techniques are usually low in capital costs; they can be maintained without a high level of expertise; and they do not involve patents, expensive copyrights and royalties. By these criteria a commercial geographical information system (GIS) is not an appropriate technology to be used in decentralized development However, the use of local renewable resources involves the adoption of end-use analysis for matching end-uses to specific sources so as to minimize the consumption of material and energy (i.e., minimize entropy). This matching requires much information which leads to what may be called the 'information-entropy trade-off; minimization of entropy requires an inverse increase in information. In this respect computers and GIS have an important contribution to make to decentralized regional planning. Drawing on a case study in Sri Lanka, this paper presents some ideas on how to incorporate GIS into local-level planning information systems.  相似文献   

2.
Abstract

Mapping variable stream buffers in a vector environment in which buffer width values are delineated often yields inaccurate results. Possible vector solutions are either ineffective or inefficient, An alternate raster approach is presented here in which a buffer effectiveness-achievement function (b-function) is introduced to map desirable buffer zones at an individual cell level based upon areal differentiations in physical and ecological conditions. The implementation of b-function is made feasible by a GIS procedure devised in this article. This tested method can be extended to a variety of variable buffer studies, such as visual buffers, noise buffers, greenways, and urban natural buffers.

‘A robe can never be made of the fur from one fox's axillae’ (A Chinese idiom).  相似文献   

3.
《The Journal of geography》2012,111(6):245-252
Abstract

Geographic information systems (GIS) is a fairly new and evolving curriculum area within geography and other disciplines at colleges and universities in the United States. The challenge of teaching underlying concepts of GIS functionality, the details of computer operation and software interfaces, as well as the contexts of various applications can be a difficult one. At Indiana University of Pennsylvania, a teaching strategy—Client-Life Cycle GIS Project Learning—has been introduced in which students in an upper level GIS course work with local organizations, faculty from other university departments, and governmental entities. This allows students with some GIS background to work with real clients; utilize and operationalize the concepts of the GIS Project Life Cycle; make the connection between data development, analysis, and applications development; provide expertise and needed data to local organizations; and see the utility and impact of their work. A group pilot project from the spring semester of 1998 is discussed to illustrate how students responded to this method of teaching GIS.  相似文献   

4.
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5.
Abstract

GIS have received increasing attention in recent years, particularly in local government. Despite the claims in the literature about the potential of the technology, to date there is still little information on the impact GIS applications are having on the organizations in which they are being implemented. With these considerations in mind this paper presents an evaluation of the findings of twelve case studies which were undertaken in a variety of British local government contexts during 1991 and 1992.

The evaluation of the findings of the case studies is divided into two parts. The first part indicates the limited impact GIS has had on the local authorities investigated even after at least two years experience. Given these findings the second part seeks to identify the issues which appear to be responsible for inhibiting the effective implementation of GIS in British local government. Overall it is suggested that some organizational cultures are inherently receptive and able to sustain the development of innovations such as GIS. However, whilst very few organizations are inherently innovative it was possible to identify four factors which appeared to enhance the chances of success. These are simple applications producing information which is fundamental to the work of potential users, user directed implementation involving the participation of all the stakeholders in the project, an awareness of the limitations of the organization with respect to the range of available resources, and a high degree of stability with respect to the general organizational environment, or alternatively an ability to cope with change. As a result the evaluation indicates that if GIS are to be effectively implemented much greater consideration must be given to the impact of organizational issues.  相似文献   

6.
Abstract

The GIS literature abounds with strategies to guide the development of a corporate GIS as a single project but lacks discussion on the long term management of the GIS. This paper documents a recent study into GIS development in a state department over an 18-year period. It applies the productional perspective of GIS to model long term GIS development diagrammatically and identifies five patterns of GIS development. The outcomes reveal some long term characteristics of a corporate GIS, based on which a three-stage approach is developed to guide the long term development of an ideal corporate GIS.  相似文献   

7.
《The Journal of geography》2012,111(6):275-276
Abstract

The integration of GIS into the secondary curriculum can aid student learning of geography. Through a partnership between a local high school and our university, high school students received nine hours of classroom instruction and field-based training on GIS and GPS to complete a mapping project. Upon completion, a test based on seven geography core curriculum units was administered to these students and to a group of university students who did not receive GIS training. Results of the test revealed that high school students significantly outperformed the university students, suggesting that GIS does aid in the learning of geographic principles.  相似文献   

8.
Abstract

A central problem in spatial analysis is the mapping of data for complex spatial fields using relatively simple data structures, such as those of a conventional GIS. This complexity can be measured using such indices as multi-scale variance, which reflects spatial autocorrelation, and multi-fractal dimension, which characterizes the values of fields. These indices are computed for three spatial processes: Gaussian noise, a simple mathematical function, and data for a random walk. Fractal analysis is then used to produce a vegetation map of the central region of California based on a satellite image. This analysis suggests that real world data lie on a continuum between the simple and the random, and that a major GIS challenge is the scientific representation and understanding of rapidly changing multi-scale fields.  相似文献   

9.
Abstract

A fragmentation index has been implemented as a region based GIS operator to describe the spatial distribution of thematic classes in one data layer within map regions defined in another data layer. It has been applied to integrated analysis of digital maps and classified remote sensing data, for estimation of landscape complexity within watersheds and for detection of logged forest stands. The properties of the fragmentation index, when applied in this manner, are discussed. The fragmentation index is suggested as a valuable means of describing image characteristics of spectrally heterogeneous map regions.  相似文献   

10.
Abstract

Application of Geographical Information Systems (GIS) to environmental problems requires a spatial delineation of soil properties and some a priori knowledge of their variability. In the U.S.A. estimated soil properties are available from soil surveys published by the National Cooperative Soil Survey. However, information on the extent and nature of their variability is generally lacking. To remedy the situation, variability of selected soil properties measured at farm and watershed scales was compared with published values using geostatistical methods. Results showed that the variability of bulk density and hydraulic conductivity can be estimated by comparing regularized variograms of measured and published values. An overlay method was proposed that combines measured and published delineations of soil properties into an overlay with the properties of both. The technique makes it possible to incorporate variability into a GIS analysis using data available from published soil surveys.  相似文献   

11.
Abstract

Local government is one of the most important groups of users of geographical information systems (GIS). The significant interest amongst users and the varied demands to be made of GIS have stimulated discussion in many countries. This article presents some of the findings of a research project which is currently exploring the impact of GIS on British local government. The discussion examines the results of a comprehensive survey of all 514 local authorities in Great Britain. These findings provide an overview of GIS adoption in relation to type of local authority and geographical location. Particular attention is focused on the type of systems which have been adopted, the take-up of GIS over time, the software and hardware being utilized and the perceived benefits and problems associated with GIS. The results demonstrate that take-up has been most pronounced in the larger authorities, particularly in the southern part of Great Britain, with the most popular combination of equipment being Arc/Info software and workstations. For those authorities presently implementing a GIS, the technology is expected to improve existing capabilities for information processing rather than enhance decision-making or help achieve savings. In seeking these benefits authorities are encountering considerable problems which include basic technical difficulties in getting the equipment to work, data-related issues surrounding the collection, standardization and maintenance of geographical information, and profound organizational considerations associated with the introduction of information technology into complex environments. There is an urgent need for in-depth case studies which evaluate the experiences of users in relation to the vital process of implementation.  相似文献   

12.
ABSTRACT

Geographical information systems (GIS) practitioners worldwide enjoy a growing array of free and open source software (FOSS) options. This software has expanded the accessibility of GIS in economically developing countries while fostering local technical expertise. This article reviews FOSS GIS uptake and advocacy in South America, especially how it relates to a climate of political friendliness toward FOSS in the region. The use or absence of FOSS GIS is assessed in public-facing web maps in South America, first at the national government level, and then at the provincial level using Argentina as a country of study. Local technical support groups and software development initiatives surrounding FOSS GIS in South America are then summarized. Finally, three case studies are presented of notable efforts to build FOSS GIS technical communities at the local level: the FOSSGIS Brasil online magazine, the Geoinquietos Argentina professional network, and the FOSS.4GIS.GOV conference in Brazil. A study of the leaders, dynamics, and practices of these groups can inform others in similar circumstances around the world who are trying to promote FOSS GIS adoption, development, skills, and services.  相似文献   

13.
Abstract

With the rapid growth in the use of geographical information systems (GIS) has come an acute shortage of skills. Although traditional techniques of education and training based on courses at various levels are being widely exploited, there is special potential in GIS for the use of demonstrators and tutors. Such computer aided learning (CAL) tools offer an effective way of putting across the graphical concepts which are vital to GIS as well as offering an attractive form of self-paced study. This paper discusses the contribution of CAL tools to GIS education and offers a short history of the techniques. A case study of the development of the Geographical Information Systems Tutor (GISTutor) is also used to illustrate the educational and technical issues behind the creation and use of such a tool.  相似文献   

14.

During the late 1980s some informal settlements were established within or near affluent Cape Town suburbs. Despite objections by suburban residents that these settlements would lead to a rapid escalation in crime and a dramatic fall in the value of properties, the authorities allowed the settlements to remain. Using data on property transfers, which are then mapped using GIS, the paper examines the effects that the informal settlement of Marconi Beam had on house prices and housing turnover within the adjacent suburb of Milnerton. The results show that most of the objections regarding Marconi Beam's effect on property values were groundless as the settlement had only a negligible effect on property values in the adjacent suburb.  相似文献   

15.
Abstract

Justifying GIS in local government is a complex task for two main reasons: first, a GIS implementation can range from a single, well-defined application in one department to a corporate multi-purpose GIS; and, second, local authorities are complex organizations currently facing major pressures for change, and considerable uncertainty about their future structure and role. The purpose of this paper is to review the potential use of cost-benefit analysis, to explore tangible and intangible benefits, to identify the costs involved, to explore the effect that a robust GIS strategy can have on the relationship between costs and benefits, and to review some of the published material on the cost-justification of GIS in local government.  相似文献   

16.
Abstract

This is the first of two papers elaborating a framework for embedding urban models within GIS. This framework is based upon using the display capabilities of GIS as the user interface to the conventional modelling process, beginning with data selection and analysis, moving to model specification and calibration, and thence to prediction. In this paper, we outline how various stages in this process based on purpose-built software outside the system, are accessed and operated through the GIS. We first deal with display based on thematic maps, surfaces, graphs and linked windows, standard to any data from whatever source, be it observations, model estimates or predictions. We then describe how various datasets are selected, how the spatial system can be partitioned or aggregated, and how rudimentary exploratory spatial data analysis enables scatterplots to be associated with thematic maps. We illustrate all these functions and operations using the proprietary GIS ARC-INFO applied to population data at the tract level in the Buffalo region. In the second part of the paper, various residential location models are outlined and the full modelling framework is assembled and demonstrated.  相似文献   

17.
Abstract

A geographical information system (GIS) based study was carried out in a densely-populated watershed in Nepal. An evaluation of land use change between 1972 and 1990 indicated that there has been an increase in forest and agricultural land area and a decrease in shrubland and grassland area. GIS techniques were used to produce single and composite fertility index maps, which can be used for problem identification and planning. These maps indicate that forest soil fertility is generally poor in the watershed. GIS was found to be very beneficial in addressing critical resource issues in small watersheds in developing countries.  相似文献   

18.
Abstract

The transfer of GIS technology has not met with uniform success in lesser-developed countries. It has been argued that this may be due to many efforts being technology-driven rather than demand-driven. In agricultural development, technology is transferred through a demand-driven participatory approach which incorporates the ultimate recipients of the technology in the design, implementation and evaluation of projects. A project to demonstrate the use of GIS technology for wasteland development in India involving seven Indian research institutes was undertaken by the U.S. Agency for International Development. In the Indian GIS demonstration, technical approaches proposed by each institute were largely technology-driven. To counter this tendency, a set of evaluation criteria or guidelines based on the participatory approach was developed to refine proposals.  相似文献   

19.
ABSTRACT

There is growing recognition of the importance of local governance, for both self-determination and the quality of decision-making. While many authors acknowledge the potential of local governments in providing opportunities for democratic engagement, there is the need for more research into the conditions under which this takes place. The objective of this research is to investigate why, or under what circumstances, local governments enhance participation in and deliberation about major projects in Australia. It does so by analysing two case studies where local governments were highly engaged in advocacy with their communities against large development projects; the East West Link tunnel in Melbourne and the Coal Seam Gas projects of Northern NSW. It finds local governments engaged in these projects due to institutional culture, practices and values, formed after demographic changes in the 1960s and 70s, and associated changes in the place-attachment qualities of residents and the nature and content of their social capital. Through historical instances of community mobilisation, these values became embedded in local governments, enabling them to respond pro-actively to subsequent threats.  相似文献   

20.
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   

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