The objective of this paper is to develop a concept of expert system based on the survey of experts' opinions and their experience concerning relations in modal split, on the basis of parameters of transport system demand and transport supply, defined through PT travel time and city size, . mean trip length. This expert system could be of use both to experts and less experienced planners who could apply the knowledge contained in this expert system for further improvement, on operational as well as on strategic level. | Yugoslav Journal of Operations Research 16 (2006), Number 1, 107-124 CONCEPT OF EXPERT SYSTEM FOR MODAL SPLIT IN TRANSPORTATION PLANNING Maja M. POPOVIĆ, Jadranka J. JOVIĆ Faculty of Transport and Traffic Engineering University of Belgrade, Belgrade Serbia and Montenegro Received: October 2004 / Accepted: March 2005 Abstract: The objective of this paper is to develop a concept of expert system based on the survey of experts' opinions and their experience concerning relations in modal split, on the basis of parameters of transport system demand and transport supply, defined through PT travel time and city size, . mean trip length. This expert system could be of use both to experts and less experienced planners who could apply the knowledge contained in this expert system for further improvement, on operational as well as on strategic level. Keywords: Modal split, transport supply, transport demand, expert system. INTRODUCTION The expert system, created in this paper, has been envisaged as a tool to be used on operational and strategic level in some segments of transport planning. The basic idea for creating such an expert system was to define relations in modal split on the basis of parameters of transport system demand and supply in one city. To enable the use of this expert system on both strategic (planning) and operational level, it is necessary to determine parameters which could be forecasted on short-term and long-term basis. For planning purposes, such an expert system should determine margins of share of specific transport modes. These limits should serve as benchmarks in forecast of the relations in modal split during planning period, on the basis of which, specific elements of future transport system are to be defined. In a similar manner this expert system can be used for operational purposes, providing that survey of parameter values is performed in the existing state or that a short-term forecast for these parameters is made. 108 . Popović,
