Kartografinių duomenų bazių valdymas

Abstract

Accumulation of a large number of digital maps poses a problem of their application in activities of utility companies and public organizations. The article advocates for one method of management and the use of a large number of digital maps. It is based on the development of automated map system. The basis of the automated map system is cartographic databases. In such a system they should be divided by territories of a certain size. Index layer is used for this purpose. The index layer is formed taking into account a number of aspects, one of them being territorial division of primary data (digital maps). The article concludes that the use of division of primary data corresponding to the index layer is appropriate in the primary stage of the automated map system development. An example organization of index layers in Vilnius city is presented. Two reading methods are used in Vilnius city. Topographic databases are divided by stereopore territory, attempting to keep the boundary coinciding with the street lines. Databases of engineering communications are divided according to the boundaries of nomenclature map sheets scale 1:2000. Since different references give different definitions of terms related to AM/FM, further the terms will be given as understood by the authors. A cartographic object is an object standing out by a distinct shape, designation, material or other characteristics which help to recognise it ( that is a street, a land plot boundary, a building etc), a real physical object. In this case, a land plot boundary or similar objects are understood as an interpreted line between the boundary turning points. A digital map is understood as a database containing information on the map. One should make a distinction between a digital map and a cartographic database. A digital map is an object peculiar to the computer drawing and construction system. It is a basis for the development of a cartographic database. And vice versa, a digital map can be a presentation of graphic objects stored in cartographic databases, for example, when giving a presentation on screen or print. A digital map can also be used for data transfer from cartographic data bases to a certain design and construction system. A cartographic database is geared towards spatial analysis, automatic search system, possibility to acquire derived data and development of a variety of reports.