Meysam Effati - Dept. of Geomatics Eng., University of Tehran, Tehran, ۱۴۳۹۵-۵۱۵, Iran
Mohammad A. Rajabi - Dept. of Geomatics Eng., University of Tehran, Tehran, ۱۴۳۹۵-۵۱۵, Iran
J. A. Rod Blais - Dept. of Geomatics Eng., University of Calgary, Calgary, Alberta, T۲N ۱N۴, Canada

Geospatial Information Systems (GIS) has considerably advanced in recent years. However, the power of GIS specially in the context of analysis is limited by uncertainty. This uncertainty mainly comes from the data sets used and the methods employed.Path finding is a term used mostly by GIS applications to plot the best route from one point to others. The basic idea behind path finding is searching a graph, starting at one point, and exploring adjacent nodes from there until the destination node is reached. Generally, the goal is of course to obtain the shortest route to the destination.This article presents the experiments related to studying path finding under spatial uncertainties. The path finding is done on the web for part of road network of Tehran, Iran. More recently, fuzzy weighted graphs, along with generalizations of algorithms for finding optimal paths within them, have emerged as an adequate modeling tool for prohibitively complex and/or inherently imprecise systems. These algorithms are reviewed and formulized with uncertainty which comes from weights on edges according to actual situation on the road such as weather conditions, and road capacity at the specified time.

GIS, Fuzzy Logic, Uncertainty, Path finding