Following the occurrence of unexpected events and natural disasters, a highly important relief operation is the transferring of relief commodities from the distribution centers (CDs) to shelters. In this paper, a three-level network consisting of depot of vehicles, distribution centers and shelters has been considered for routing and scheduling of relief vehicles through introducing a multi-obj...

Energy requirements push the shipping industry towards more energy-efficient ships, while environmental regulations influence development of environmentally friendly ships by replacing fossil fuels with alternatives. Current mathematical models for ship energy efficiency, which set analysis boundaries at level power system, are not able to consider alternative as a powering option. In this pape...

Fleet repositioning problems pose a high financial burden on shipping firms, but have received little attention in the literature, despite their high importance to the shipping industry. Fleet repositioning problems are characterized by chains of interacting activities, but state-of-the-art planning and scheduling techniques do not offer cost models that are rich enough to represent essential o...

Existing ship scheduling approaches either ignore constraints on ship draft (distance between the waterline and the keel), or model these in very simple ways, such as a constant draft limit that does not change with time. However, in most ports the draft restriction changes over time due to variation in environmental conditions. More accurate consideration of draft constraints would allow more ...

Time-dependent Vehicle Routing Problem is one of the most applicable but least-studied variants of routing and scheduling problems. In this paper, a novel mathematical formulation of time-dependent vehicle routing problems with heterogeneous fleet, hard time widows and multiple depots, is proposed. To deal with the traffic congestions, we also considered that the vehicles are not forced to come...

We study the maintenance task scheduling problem for an aircraft fleet in uncertain environment from viewpoint of robust optimization. Given a daily horizon, tasks delegated to shop should be scheduled such way that sufficient aircrafts are available on time meet demand planned missions. The either activities or unexpected repair jobs when major fault is detected during preor after-flight check...

In this paper we present a local search heuristic method for an integrated airline scheduling, fleeting and pricing model. The integrated model simultaneously optimizes the decisions of schedule design, fleet assignment, seat allocation, pricing and considers passengers’ spill and recapture. The resulting problem is a mixed integer non-convex problem due to the explicit representation of a dema...