The split pickup split delivery crude oil tanker routing and scheduling problem is a difficult combinatorial optimization problem, both theoretically and practically. However, because of the large expenses in crude oil shipping it is attractive to make use of optimization that exploits as many degrees of freedom as possible to save transportation cost. We propose a nested column generation algo...

We consider the vehicle routing problem with stochastic demands (VRPSD). We give randomized approximation algorithms achieving approximation guarantees of 1 + for split-delivery VRPSD, and 2 + for unsplit-delivery VRPSD; here  is the best approximation guarantee for the traveling salesman problem. These bounds match the best known for even the respective deterministic problems [Altinkemer, K...

We address a single commodity Pickup and Delivery Vehicle Routing Problem from the literature. A network of customer nodes is given with both travel times costs. fleet vehicles limited capacity exploited to satisfy node demands, set routes must be found such that vehicle capacities are never exceeded, each route does not exceed time resource, cost minimized. The demands pickup delivery can spli...