THE USE OF FUZZY-SETS FOR RESOURCE-ALLOCATION IN AN ADVANCE REQUEST VEHICLE BROKERAGE SYSTEM - A CASE-STUDY

Community transport vehicle brokerage operators match the needs of gro ups without minibuses with the spare capacity of groups which own mini buses. They take bookings in advance, and allocate vehicles without kn owing what the total demand will be for travel at a certain time. An a pproach has been developed which ranks vehicles according to a sequenc e number which indicates how 'difficult to book' they are, and present s the most difficult to book to the broker first, with the intention o f maintaining the maximum flexibility in the system. The concept 'diff icult to book' is not easy to define exactly. Fuzzy set theory provide s a mechanism for dealing with imprecise concepts, and through fuzzy l ogic for reasoning about such concepts. Fuzzy inferencing systems cons ist of linguistic variables, fuzzy sets, rules, and methods to combine the sets and produce a final result. Fuzzy logic has been used to pro vide a means of automating the allocation of sequence numbers to vehic les. Three different approaches to developing the rules for this syste m have been tested, by simulating bookings, and the one which produced the best results was based on a knowledge acquisition process involvi ng booking staff. This approach resulted in the allocation of the high est number of trips and in leaving the least hours of travel unallocat ed.