The study deals with information systems for the location of traffic accidents in urban areas. Theory concerning locating information has been studied. The report describes four general information systems for land use planning and six registers which have mainly been designed for traffic accident data. Physical environment is described with areal reference objects. In information systems areal reference objects are described by counterparts: points, segments and polygon. Information is located by geocodes. Codes are signs which attach information for instance to a known area. The use of coordinates enables calculation of distances, choosing the edges of the studied area freely and producing maps with computer. Location systems are based on segments. In these systems the areal reference object, street network, is located as segments with the help of coordinates. The registers which are mainly designed for traffic accidents use network systems for locating. The areal reference object is usually a street sequence, which is located by codes. Usually traffic accident registers include information of street network only about the places where traffic accidents have occurred. A description of the whole street network can be included also in the four systems studied here.
Abstract