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1.

A statistical model for automated mapping of the spatial distribution of permafrost in the area of Corral del Veleta in south-east Spain (3703' N, 322' W; 3398 m a.s.l.) was developed and applied. The model uses a relationship between permafrost occurrence as indicated by BTS measurements, and variables such as altitude, solar radiation and summer snow cover. The model was implemented within a geographical information system (GIS) and determines the spatial distribution of probable permafrost in Corral del Veleta. Validation was achieved by comparing the predicted permafrost distribution with the results of recent fieldwork, such as geomorphic mapping, geophysical soundings and ground temperature logging.  相似文献   

2.
Abstract

The field of geographical information systems (GIS) is reviewed from the viewpoint of spatial analysis which is the key component of the familiar four-part model of input, storage, analysis and output Input is constrained by the limits of manual methods and problems of ambiguity in scanning. The potential for developments in output is seen to be limited to the query mode of GIS operation, and to depend on abandoning the cartographic model. Discussion of storage methods is organized around the raster versus vector debate and the need to represent two spatial dimensions in one. A taxonomy of GIS spatial analysis operations is presented together with a generic data model. Prospects for implementation are discussed and seen to depend on appropriate scales of organization in national and international academic research.  相似文献   

3.
Abstract

Growth in the available quantities of digital geographical data has led to major problems in maintaining and integrating data from multiple sources, required by users at differing levels of generalization. Existing GIS and associated database management systems provide few facilities specifically intended for handling spatial data at multiple scales and require time consuming manual intervention to control update and retain consistency between representations. In this paper the GEODYSSEY conceptual design for a multi-scale, multiple representation spatial database is presented and the results of experimental implementation of several aspects of the design are described. Object-oriented, deductive and procedural programming techniques have been applied in several contexts: automated update software, using probabilistic reasoning; deductive query processing using explicit stored semantic and spatial relations combined with geometric data; multiresolution spatial data access methods combining poini, line, area and surface geometry; and triangulation-based generalization software that detects and resolves topological inconsistency.  相似文献   

4.
Abstract

Geographical information systems (GIS) provide the decision-maker with a powerful set of tools for the manipulation and analysis of spatial information. The functionality of GIS is, however, limited to certain deterministic analyses in key application areas such as spatial search. The integration of multi-criteria evaluation (MCE) techniques with GIS is forwarded as providing the user with the means to evaluate various alternatives on the basis of multiple and conflicting criteria and objectives. An example application based on the search for suitable sites for the disposal of radioactive waste in the UK using the Arc/Info GIS is included. The potential use of a combined GIS-MCE approach in the development of spatial decision support systems is considered.  相似文献   

5.
《The Journal of geography》2012,111(5):213-217
ABSTRACT

Spatial literacy is a new frontier in K–12 education. This article describes a place-based introductory GIS/GPS middle school curriculum unit in which students used measuring tools, GPS units, and My World GIS software to collect physical and spatial data of trees to create a schoolyard tree inventory. Maine students completed “memory maps” of their schoolyards as a pre/post exercise assessment. A statistically significant increase in students’ spatial awareness was documented. A technology-based curriculum can significantly increase students’ spatial awareness especially in a place and context relevant to each student.  相似文献   

6.
Abstract

The opportunities available at a demand location are usually measured as the costs of reaching a specified critical number of facilities from that location. This method does not however, account for multistop trips nor for differences in the diversity of supply at the level of individual facilities. In this paper we introduce an alternative measurement method that overcomes these shortcomings. In this method the probability of successfully visiting a specific facility is assumed to be a function of the diversity of supply provided. Trip routes are constructed that have an acceptable probability of success. Then, the expected costs of travelling the optimum route are determined as an indicator of spatial opportunities. The proposed method has been implemented in a GIS environment, using typical GIS data and GIS tools for spatial analysis and display. The results of a case study indicate that the new method, compared to current methods, may lead to different evaluations of the level of opportunities at demand locations.  相似文献   

7.
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8.
ABSTRACT

The establishment of the National Key Centre for Social Applications of Geographical Information Systems (GIS) in 1995, under the directorship of Professor Graeme Hugo, was a turning point in the use of GIS in Australia. The field of GIS, previously dominated by environmental applications, now broadened its focus to include populations, services and the interactions between people and the environment. Social applications of GIS offered a unique opportunity to make service planning, reporting, funding allocations and research both smarter and fairer. Geography and geographic relationships as implemented in GIS became the integrating platform for social spatial information, invigorating social research, planning and policy. A key strength of this approach, recognised by Professor Hugo, was the ability to ‘put people back into the planning process’. Further to being an integrating platform, GIS also offered the ability to generate new information and knowledge, which could facilitate evidence-based decision making. This paper focuses in particular on providing a written record of the development of the Accessibility/Remoteness Index of Australia (ARIA) suite of spatial accessibility indices. The lasting legacy and continued relevance of this work in social applications of GIS is also reviewed in this paper, with reference to key examples of how social research and planning in Australia have been made both smarter and fairer through the contributions of Professor Hugo and his team.  相似文献   

9.
北京西北地区景观格局优化   总被引：8，自引：0，他引：8  
Supported by the technologies of remote sensing (RS) and geographical information system (GIS), we chose northwest of Beijing as a study area and gave priority to understanding of the spatial-temporal characteristics of landscape pattern change through visually interpreted Landsat TM images of 1989, 1996 and 2005. It is believed that there were a series of landscape ecological problems caused by city expansion: landscape ecological connectivity was low; landscape structure was simplified; the fragmentation of green land patch was more obvious on the plain areas, moreover, spatial distribution of green land was unbalanced. For this reason, this study adopted accumulative cost distance model, combined with ecosystem services and spatial interactions of landscape types, analyzed the spatial difference of the ecological function and the compactness of landscape structure in the study area, and further discussed the landscape pattern optimization proposal. We find that it is essential to protect and establish ecological sources, to establish urban ecological corridors, and to establish ecological nodes at the landscape ecological strategic positions so as to intensify spatial relationships among landscape elements and maintain continuity of landscape ecological process and pattern in the course of city expansion. The methods and final results from this study are expected to be useful for landscape ecological planning in Beijing region. Foundation: Program for New Century Excellent Talent in the University, No.NCET-06-0122; The National Water Special Project, No.2008ZX07526-002-02; Specific Financial Funds Project of Beijing Academy of Science and Technology (BJAST), Platform Construction for Typical Contaminated Soil Remediation Technology of Beijing (2008A-1); Plan Support for Innovative Team (2008A-6) of BJAST; NSFC, No.30871964; BJNSFC, No.4073036 Author: Yue Depeng (1963–), Ph.D and Associate Professor, specialized in desertification control, landscape ecology and land evaluation.  相似文献   

10.
Abstract

During the 1980s techniques for analysis of geographical patterns have been refined to the point that they may be applied to data from many fields. Quantitative spatial analysis and existing functions available in geographical information systems (GIS) enable computerized implementations of these spatial analysis methods. This paper describes the application of quantitative spatial analysis and GIS functions to analysis of language data, using the extensive files of the Linguistic Atlas of the Middle and South Atlantic States (LAMSAS). A brief review of recent development of using quantitative and statistical methods for analysing linguistic data is also included.  相似文献   

11.
Abstract

This paper describes the architecture and working of a recently implemented knowledge-based GIS (KBGIS-II) that was designed to satisfy several general criteria for GIS. The system has four major functions, query-answering, learning, editing and training. The main query finds constrained locations for spatial objects that are describable in a predicate-calculus based spatial object language. The main search procedures include a family of constraint-satisfaction procedures that use a spatial object knowledge base to search efficiently for complex spatial objects in large, multi-layered spatial data bases. These data bases are represented in quadtree form. The search strategy is designed to reduce the computational cost of search in the average case. The learning capabilities of the system include the addition of new locations of complex spatial objects to the knowledge base as queries are answered, and the ability to learn inductively definitions of new spatial objects from examples. The new definitions are added to the knowledge base by the system. The system is currently performing all its designated tasks successfully, although currently implemented on inadequate hardware.  相似文献   

12.
《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   

13.
Why not SQL!     
Abstract

The application of traditional database query languages, primarily the Structured Query Language SQL, for geographical information systems (GIS) and other non–standard database applications has been tried unsuccessfully; therefore, several extensions to the relational database query language SQL have been proposed to serve as a spatial query language. It is argued that the SQL framework is inappropriate for an interactive query language for a GIS and an extended SQL is at best a short term solution. Any spatial SQL dialect has a number of serious deficiencies, particularly the patches to incorporate the necessary spatial concepts into SQL.  相似文献   

14.

Two qualitative case studies, one focusing on K-12 teachers and the other on middle school students, explore key factors associated with using Geographic Information Systems in the classroom. In both studies, access to appropriate hardware is a critical barrier. Time is another critical barrier—time to learn the GIS software and time in the curriculum to incorporate GIS as a learning experience. In both case studies, learning the technology at the expense of learning spatial analysis was a danger, suggesting the need for conscious focus on the goal of using GIS to learn how to “do geography.”  相似文献   

15.
Book Reviews     
《The Journal of geography》2012,111(6):282-291
Abstract

This paper summarizes a research project conducted to investigate the strategies developed by middle school students to solve a route-finding problem using Arc View GIS software. Three different types of route-finding strategies were identified. Some students were visual route-finders and used a highly visual strategy; others were logical route finders and used GIS software tools to apply a more analytical and systematic approach. A third group were transitional route-finders who used an approach that showed evidence of one that was shifting from a visual strategy to one that was more logical. The findings suggest that to be most effective, GIS teaching and curriculum development strategies should begin with an assessment of student understanding of spatial relationships and continue with a progression that spirals according to the evolution of student cognitive mapping skills over time.  相似文献   

16.
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   

17.
Abstract

GIS is a technology which is ideally suited to analysis of the market values of properties, since such values are based upon spatial comparisons as well as individual property attributes. Great Britain now has a new mechanism of local taxation, the council tax, which is based upon the capital values of properties. Central to the implementation of this tax has been the potentially controversial assignment of properties to valuation ‘bands’. This paper posits that a geographical model embedded within a GIS provides an alternative means of devising credible capital values, and anticipates some of the prospects for the use of GIS in local revenue-raising.  相似文献   

18.
Abstract

This paper reports on software to construct alternative weight matrices and to compute spatial autocorrelation statistics, namely the Moran coefficient and the Geary coefficient using Arc/Info’s data structure. As such it is an addition to recent efforts in linking GIS with exploratory spatial data analysis. The software is interfaced with Arc/Info via the Arc Macro Language (AML) so that it can be run in the ARC environment. This allows the user to perform exploratory analysis within GIS which may provide insights in subsequent spatial analysis and modelling.  相似文献   

19.
Abstract

This paper presents the development of the first geographical information system (GIS) that may be used to manipulate a single dataset at a very large range of scales (different detail levels). The design of this multi-scale GIS is fully integrated in the open DBMS Postgres and the open GIS GEO + + . Besides the system design, this paper will also give details of the implementation in the Postgres DBMS environment of three generalization tools: 1. the BLG-tree for line and area simplification, 2. the Reactive-tree for selection based on importance and location, and 3. the GAP-tree for solving problems when using the other two structures for an area partitioning. Together with the geographical frontend, the DBMS forms the flexible basis for the realization of powerful GIS applications. The implementation has been successfully benchmarked with two large datasets: World Databank II and DLMS DFAD. The response times improve by one to two orders of magnitude.  相似文献   

20.
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   

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