AN AUTOMATED INTERNET GEOINFORMATION SERVICE FOR INTEGRATING ONLINE GEOINFORMATION SERVICES AND GENERATING QUASI-REALISTIC SPATIAL POPULATION GIS MAPS

摘要

This paper presents the design and realisation of a low-cost automated internet geoinformation service, named Kingston Automated Geoinformation Service (KAGIS), that provides the United Kingdom's academic community with fully processed quasi-realistic GIS maps of spatial population distribution, known as dasymetric maps. The key innovative aspect of the service is that it undertakes spatio-temporal interpolation for census area statistics and enable users to overcome the difficulties associated with inconsistent boundaries used by different census events. It is designed and programmed to carry out live, on-demand online integration of Edinburgh University's geospatial data service (EDINA) and Manchester University's census data service (MIMAS), to automatically geoprocess and deliver digital dasymetric maps for any of 2001, 1991 and 1981 census years and any area of interest at all census area levels in the United Kingdom as per user's request. The system is capable of automatically handling large GIS datasets in accordance with users issuing requests. The system unleashes a large amount of geospatial and census data held in these formerly isolated digital repositories and carries out all necessary data processing to generate the requested spatial information products in a novel workflow. The online data transmission, retrieval, integration, processing and generation of quasi-realistic spatial population (dasymetric) GIS maps at the English county level typically take 2 minutes. KAGIS enables census data special interest group in the UK's academic community to access and utilise this newly available geoprocessing service for a wide range of applications, such as analysing population changes over the time and undertaking fine resolution detailed spatial population estimation for planning at various scales and areas of interest. Online interactive selection of datasets and the entire procedure of online heterogeneous data integration, areal interpolation and data processing for dasymetric maps with ancillary landuse maps derived from remotely sensed imagery are automated to offer end users opportunities to simply follow a few instructive checkbox and button-clicking steps to obtain resultant digital dasymetric maps. The design of KAGIS adopts the service oriented design architecture to couple the latest web portal technology and ArcGIS Server technology to realise the new secure internet geoinformation service with a set of specially designed and coded geoprocessing programs performing coherent chained actions in a novel workflow and it is programmed as a novel stateful application to be able to provide the runtime online data integration, processing and resultant GIS map delivering service to concurrent internet users. Novel aspects of KAGIS include its operation as a new fully integrated service system that acts as an automated online integrator, data processor, e-content generator and secure service deliverer. The system innovatively carries out live, flawless, on-demand combination of formerly isolated geospatial and census data-only repositories and services according to user requests. The novel design of coherently chained modules and workflow enables fully automated processes for real-time digital data acquisition, realtime data processing for on-demand GIS model generation and service delivery. The whole and parts of the secure online service technology of KAGIS are generic and universally applicable in any countries in the world. With the process of globalisation and development, all countries have been and are undergoing significant development and change. The technology and know-how experience of KAGIS can assist any country in the world to develop its secure internet GIS services, integrating geographical information for specific decision making systems as well as providing low-cost and efficient ways to process and utilise existing geographical data for a multitude of purposes such as development planning.