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Land titles -- Registration and transfer, Multipurpose cadastres -- Technological innovations, Multipurpose cadastres -- Data processing, Object-oriented programming (Computer science)

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22 pages


Research exploring the object-oriented paradigm as a tool with which to model location of objects in maps is reported. The research led us into three areas:

  • the use of an object-oriented language, Smalltalk.-80 to model cadastral location using the object-oriented paradigm.
  • study of the development of spatial information systems, such as engineering design and computer-aided design(CAD) database systems based on object-oriented ideas, to see how that approach might be useful for developing a mapping system.
  • Finally, the conceptual exploration of how an object-oriented approach might facilitate linkages of location among layers of a land information system.

Future research is needed to produce a more convincing prototype of a cadastral map. Since Smalltalk is a single-user, programming language environment, it does not produce objects that persist beyond the existence of the program in which they are created and manipulated. Computer-aided cadastral mapping requires an environment capable of working with persistent objects accessible by multiple users. This led to an investigation of present and future directions in database system development.

We see a productive course in continuing researeh cm the object-oriented programming language. prototype, adding more kinds of locational methods, improving the interface, and studying alternative structures to the Dictionary-based Cadastral Map. Meanwhile, by keeping an eye on the development of object-oriented database systems, it should be possible to find one that can be made to manipulate spatial information. Fmally, we hope to continue exploration of how the object-oriented paradigm will be useful, in mapping and geographic analysis generally.

While the research reported here has emphasized cadastral objects, the paradigm for locational determination has a broad potential for application. Shared or common boundaries among layers or data· types can be addressed by an object-oriented database approach, which lends itself to better handling of the interrelationships among objects of different types.


Catalog Number PR028.

A product of the Center for Urban Studies, College of Urban and Public Affairs, Portland State University.

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