IEDC-2010 Conference Proceedings (Download ... - NED University

Figure 2. Spatial distribution of ERV’s (ambulance) location in Karachi Urban area
5. Geospatial Analysis
5.1. Spatial Intersection between RTI and Buffer zones
Using Road traffic injury (RTI) database file from Road Traffic Injury Research & Prevention Centre,
having detail of all injuries occurred in several location of Karachi City in the year 2008 have been
spatially analyzed in Geomedia.pro Software. Spatial Intersection is used in GIS for correlating two
features, (point) feature as an accident location and town geometrically represented by (Polygon) on map.
In this paper polygon feature used as a based layer of Buffer Zones around ERV‘s placement location
while point feature class used as an accident locations.
Buffers such as area of different radius around a map have been created within and outskirt area of
Karachi City. The purpose of creating buffers of different radius sizes was to accommodate variation in
traffic volume or flow pattern of vehicles in congested areas. Larger radius of buffer created along the
periphery of Karachi City, which covered accidents records along with ERV‘s location on remote areas or
towns such as hub, gadap town, and keemari town etc.Whereas buffer of smaller radius created within the
city, where numbers of accidents have been analyzed for smaller distances.
By using command of (contained by) intersection between above mentioned features has been displayed
in Figure 3 , in which feature point shows only those injuries which occupied by buffer zones of ERV‘s
such that if accidents occurred within the buffer zone, then ambulance can easily reach to the victim place
w.r.t its location nearer to the zone.
Proceedings of IEDC 2010, 1-3 July, 2010
415
IEDC-522-088