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Integrating space and time in an object-based GIS : a case study of public boundary evolution

Embedding the time-geographic framework within a GIS is accomplished by using the object-oriented analysis and design method proposed by Booch. This method assures the object-oriented decomposition in which the complexity of the concepts developed in the time-geographic framework are transposed to a meaningful collection of objects. These interact in different kinds of scenarios within a <I>spatio-temporal data model</I>. In addition, inheritance has been adopted as the incremental change mechanism within the spatio-temporal data model because of its usefulness in subclassing the evolutionary processes of incremental change within the time-geographic framework. A taxonomy of change is proposed on the basis of the spatio-temporal data model, designed for embedding the time-geographic approach. A version management approach plays an important role in managing changes within the spatio-temporal data model. The version management method developed by Ahmed and Navathe has been selected because of its consistency with object-oriented concepts. The main concepts of this method are described and its incorporation into the spatio-temporal data model is presented in the thesis. The GIS application chosen to evaluate the spatio-temporal model is the study of the evolutionary aspects of public boundaries. Public boundaries represent the line of physical contact between administrative units in Great Britain. The arrangement of public boundaries forms an irregular tessellation of polygons that represent the whole hierarchy of local government and European Constituency areas. Approximately 3,000 changes occur to political boundaries in England every year. The spatio-temporal data model describes the processes which most of the public boundaries would pass through in their lifespan as well as the different evolutionary states which reveal the changes occurring over a public boundary lifespan. Finally, the implementation aspects involved in incorporating the spatio-temporal data model into an object-based GIS are discussed. The Smallworld is used for implementing the spatio-temporal data model and the issues arising from this implementation of the theoretical framework are identified and assessed.

Identiferoai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:663316
Date January 1996
CreatorsWachowicz, Monica
PublisherUniversity of Edinburgh
Source SetsEthos UK
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Sourcehttp://hdl.handle.net/1842/21593

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