ISSN:1365-8816    

DOI:10.1080/136588100750022732

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

ISSN:1365-8816    

DOI:10.1080/136588100750022741

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Recommendations for implementation and evaluation of Geographical Information Systems (GIS) can benfit from a broader theoretical foundation to support investigation, understanding and improvement. This paper discusses Actor-Network Theory (ANT) as a framework to delineate and evaluate the social and technical interactions involved in GIS implementation. The proposed process traces actor-network interactions through texts, technical objects, people, money and control. Actor alignment, actor-network stability and obligatory points of passage are evaluated to compare actor-networks. Case study research on conservation GIS implementation in Ecuador illustrates these methods. The strength of these actor-networks is examined through analysis of actors' interactions and the presence and function of an obligatory point of passage. Stronger actor-networks exhibit alignment among actors, co-location of an obligatory point of passage with the center of calculation and credit sharing.

ISSN:1365-8816    

DOI:10.1080/136588100750022750

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

It is argued that there is no simple metadata solution to the problems of integrating information from multiple scientific disciplines in biodiversity and thus to problems of adopting GIS for producing maps of biodiversity. To the contrary, it is maintained that within this field, GIS needs to take account of and represent an irreducible ontological diversity in the many biodiversity databases being produced.

ISSN:1365-8816    

DOI:10.1080/136588100750022769

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

The Harvard Lab for Computer and Spatial Analysis was one of several sites in the early development of GIS where seminal innovations in the processing and display of geographically referenced data took place. An early area of concern at the lab were the mathematical and technical problems associated with the modelling of ‘surfaces’. This term, ‘surface’, came to take on new and sometimes abstract meanings. The language used to describe ‘surfaces’ was rooted in tacit knowledge and more formal mathematics. The mixing of different forms of language, both verbal and written, allowed the passing of abstract and sometimes difficult meanings. It may be that universal history is the history of a handful of metaphors... It may be that universal history is the history of the different intonations given a handful of metaphors (Borges 1964, p. 189 and 192).

ISSN:1365-8816    

DOI:10.1080/136588100750022778

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

This paper proposes a new framework to understand the use and value of GIS by social movement groups and to transcend the contested debate over how and whether GIS should be adopted. It frames the debate in terms of the conforming properties of GIS. The proposal is that conservation GROs must conform to GIS to ensure effective usage; however, in the process of that use, they mould the GIS to their own objectives. Various examples from the North American conservation movement illustrate the properties of GIS conformity and likely outcomes of research. This paper asks the reader to rethink PPGIS and GIS diffusion. It also poses questions for further research that frames adoption as an issue of conformity.

ISSN:1365-8816    

DOI:10.1080/136588100750022787

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

In this paper we discuss uses of image segmentation, feature extraction and Bayesian networks for identifying buildings in digital orthophotos and the utilisation of the results for the automated computation of building statistics. Our work differs from previous attempts in a number of ways. Firstly, image segmentation is accomplished using an adaptive multi-scale method which brings together region and edge information to segment the image into regions. Secondly, automated building feature extraction (e.g. corners) is optimised to fit with expert human annotation performance. The third aspect of this work is the exploration of Bayesian networks as a method for fusing available information (ranging from corner information to solar angles as indicators of shadow location) to classify segmented regions as corresponding to buildings or not. Such processes then permit the automatic compilation of building statistics.

ISSN:1365-8816    

DOI:10.1080/136588100750022796

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

The central problem of a combined analysis of digital terrain models (DTMs) and other landscape data is determination of a DTM grid size (w) providing a correct study of relationships between topographic variables and landscape properties. Generally, an ‘adequate’wis determined by an expert estimate, and solutions are largely subjective. We developed an experimental statistical method to determine an adequatewfor DTMs applied to landscape studies. The method includes the following steps: (a) derivation of a DTM set using a series ofwi, (b) performance of a correlation analysis of data on a landscape property and a topographic variable estimated with variouswi, (c) plotting of correlation coefficients obtained versusw, and (d) determination of smoothed plot portions indicating intervals of an adequatew. We applied the method developed to study the ifluence of topography on the spatial distribution of soil moisture (M) at a micro-scale. We investigated the dependence ofMon gradient (G), horizontal (kh), vertical (kv), and mean (H) landsurface curvatures. For DTM derivation, we used 13 values ofwifrom 1 to 7m. An interval of adequatewiforMfalls between 2.25 and 3.25m in the given terrain conditions. In absolute magnitudes, correlation coefficients are largest within this interval; correlation coefficients ofMwithG,kh,kvandHare 0.28, 0.52, 0.50 and 0.60, respectively, forw= 3m. The results obtained demonstrate that the method actually works to identify an adequatewat a micro-scale. The method developed allows estimation of an adequate area of landform which ‘realise’ a topographic control of landscape properties.

ISSN:1365-8816    

DOI:10.1080/136588100750022804

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

This paper applies generalised linear statistical techniques in a GIS to analyse wildlife data from a Kenyan wildlife reserve and its surrounding areas. Attention focuses on the spatial distribution of elephant during nine successive surveys, analysing their temporal and spatial relationship to 12 environmental covariates. A principal component analysis identifies five major determining factors, thereby reducing dimensionality in the data, while a simple spatial analysis procedure, suitable for wildlife data obtained from airborne surveys, quantfies clustering for different animal species. The number of explanatory variables appearing in abundance models is found to be subject to large variations during successive surveys with a minimum and maximum of four and eight variables, respectively. Species from highly clustered populations are found to have over 20 times more observations within short distances compared to the rest. The study concludes that a combination of generalised linear modelling and GIS gives deeper insight into the dynamics of wildlife species in and around well-defined nature reserves.

ISSN:1365-8816    

DOI:10.1080/136588100750022813

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Spatial databases are used in many natural resources management applications. These databases help decision-makers to design location specfic plans for resource management. In this paper, a geographical information system is used to develop a spatial energy information system model. The model has been used to examine the energy situation in a rural area of a developing country. It can help energy planners to assess the need for energy interventions specfic to certain regions in the planning area.

ISSN:1365-8816    

DOI:10.1080/136588100750022822

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor