Integration of Fixed and Flexible Route Public Transportation Systems, Phase II.

摘要

Conventional bus service (with fixed routes and schedules) has lower average cost than flexible bus service (with demand-responsive routes) at high demand densities. At low demand densities flexible bus service has lower average costs and provides user-friendly door-to-door service. Bus size is interrelated with service type since large buses have lower average cost per passenger than small buses at high demand densities, and vice versa. The service type and vehicle size decisions are jointly optimized here for a bus transit system connecting a major terminal to local regions. Bus sizes, conventional route spacing and flexible service area are the decision variables in a proposed algorithm which optimizes a multi-dimensional nonlinear integer optimization problem. Numerical analysis shows how the proposed Variable Mode & Multiple Fleets Operation can reduce total cost compared to a Single Fleet & Single Mode operation. The sensitivity of results to important parameters is explored.