Fleet Sizing for Reservation-Based Car-Sharing Services Allowing Cruise Parking

Fleet sizing is an important problem in the planning procedure of one-way car-sharing systems. This article investigates the fleet-sizing problem for reservation-based car-sharing systems allowing cruise parking. The system with traffic congestion is modeled as a mixed queuing network with its servers mapping the remaining road capacity. The optimal fleet size with maximum operating profit is derived, taking into account asymptotic performance metrics like reservation, vehicle availability and utilization, and occupancy of parking spaces of each of the stations. The solution is obtained based on an exact mean value analysis (MVA) algorithm and an approximate Schweitzer-Bard MVA (SB-MVA) algorithm. Numerical experiments demonstrate that the proposed method with cruise parking can meet the travel demands with greatly reduced operating cost. Another interesting finding is that a larger reservation time window implies lower parking capacity and smaller fleet size, whereas, as the time window exceeds a threshold, reducing the fleet size may damage the quality of service.