Strategies for Associating Data and Location in a Geographic Information System

摘要

Much of the existing work in the area of Geographic Information Systems (GIS) treats spatial objects, e.g. points, lines, and regions, as the primary entities of interest. In that approach, descriptive information is associated directly with each of these data items. This paper explores the feasibility of implementing an alternative design which uses Location Data Sets and Location Predicates as the basic entities managed by a Location Data Management System (LDMS). A major advantage of the proposed approach is its suitability for automatic enforcement of data consistency across multi-scale geographic entities. The central idea of the Location Data Set approach is that spatial data should be directly associated with locations rather than named regions or points. The relationships between geographic entities and data values may then be derived through the intermediate relationship of shared location. It is envisioned that each type of data which is distributive in nature would be stored in a separate set. Data values associated with conventional points, lines, and regions would then be merely restrictions on these global data sets. This is similar to the way in which the external views of a database represent a subsetting of the global data. The paper includes a survey of fifteen selected GIS implementations and existing work relevant to identified implementation obstacles. (Author)