On March 24, Baoxiang Li will defend her thesis entitled:
Optimization of People and Freight Transportation, Pickup and Delivery Problem Variants
In her thesis, Baoxiang Li studies the feasibility of transportation resource sharing in taxi based people-freight systems and bicycle-sharing systems, and to improve the usability of the both. The first part of the research focuses on the taxi resource being shared by both people and freight, while the second part is related to bicycle redistribution between dif- ferent bicycle stations.
Specifically, the taxi sharing models concern the design of combining people and freight flows by taxis. The taxi sharing service can provide extra options for both passengers and parcels. From a passenger and parcel delivery company perspective, they can gain cheaper trips, especially in rural areas where the population density is low. From a taxi driver perspective, the drivers can gain more profit. Furthermore, it reduces the congestion and air pollution because the same transportation needs can be met with fewer vehicles and drivers. This problem is denoted as the Share-a-Ride Problem.
We present MILP formulations and perform a numerical study of both static and dynamic scenarios. The obtained numerical results provide valuable insights into successfully implementing a taxi sharing service. In the third chapter, we propose an adaptive large neighborhood search (ALNS) heuristic.
The second part, on the bicycle-sharing system, is focused on improving existing bicycle sharing services by using vehicles to transport bicycles from full stations to stations with shortages to balance the bicycle sharing network. She formally defines the problem and present a mathematical formulation. This formulation, however, is too complex for exact solvers. We propose a hybrid ALNS method to solve this problem.
More information is available here. The full thesis is available after March 24, 2016.