USING GIS ANALYSIS IN TRANSPORTATION NETWORK

Many applications in GIS are characterized by data network representing and analysis. Network analysis is based on linear structures. The fields where these types of analysis are used are different, such as: roads network, electric networks, hydrographic network and so on. For example, a hydrographic network is characterized by a one way direction (the water will flow in the same direction) with no return. Instead a road network can be crossed in both directions. A line from a network is characterized by: length, direction, connectivity and information about the outflow for crossing the network. The ways of representation that can include all these features are graphs. The subject of this paper involves the identification of the minimum cost of a route between 2 localities by using the landuse between them. In order to solve these problems we used a GIS software which allows such an analysis, specifically ArcGIS v10. For finding the easiest way to get from a source point (locality) to a destination point (locality) by using the characteristics of the land we will consider landuse meaning how difficult is moving on it depending on what is on the surface and the slope. The steeper the slope, the harder the movement will be. The Euclidian distance and the Cost distance represent 2 main methods to accomplish a distance analysis in ArcGIS Spatial Analyst. The Euclidian distance functions measure the shortest distance between every cell until the closest source point. In this way we can determine the allocation, distance and direction towards the closest source point. The Cost distance evaluation function modifies the Euclidian distance by adding a variable associated with the displacement between any 2 given cells. For example, the distance to destination point could be shorter by climbing a mountain, but it could be faster going around the certain mountain. The cost allocation function identifies the source cell for which a minimum cost will be determine based on the accumulated cost of the displacement. This function creates a map of the routes identifying the necessary route from any cell to the closest source point. It also can create a raster representing the distance and the direction, and it can as well calculate the minimum cost or the shortest route from a source point to destination point.