This paper describes a tabu search heuristic for the vehicle routing problem with soft time windows. This problem allows lateness at customer locations although a penalty is then incurred and added to the objective value. By adding large penalty values, the vehicle routing problem with hard time windows can be addressed as well. In the tabu search, a neighborhood of the current solution is crea...

The vehicle routing problem with time windows (VRPTW) is a representation of a wellknown transportation problem. It involves customers, depot, vehicles and constraints on delivery time (time windows) and capacity on vehicles. To minimize cost, the solution of a VRPTW problem must satisfy all the constraints while minimising the total distance for the lowest number of vehicles. Clearly an order ...

the location-routing problem is a relatively new branch of logistics system. its objective is to determine a suitable location for constructing distribution warehouses and proper transportation routing from warehouse to the customer. in this study, the location-routing problem is investigated with considering fuzzy servicing time window for each customer. another important issue in this regard ...

Many real-world optimization problems today are multi-objective multi-constraint generalizations of NP-hard problems. A classic case we study in this paper is the Inventory Routing Problem with Time Windows (IRPTW). IRPTW considers inventory costs across multiple instances of Vehicle Routing Problem with Time Windows (VRPTW). The latter is in turn extended with time-windows constraints from the...

In this paper, a new approach to risk minimizing vehicle routing and scheduling problem is presented. Forwarding agents or companies have two main concerns for the collection of high-risk commodities like cash or valuable commodities between the central depot and the customers: one; because of the high value of the commodities transported, the risk of ambush and robbery are very high. Two; the ...

Considering the vehicle routing problem with fuzzy demand and time windows, a optimization method is proposed considering both soft windows uncertain customer demand. First, chance-constrained programming model established based on credibility theory, minimizing total logistics cost. At same time, random simulation algorithm designed to calculate penalty cost of delivery failures caused by that...

The NP-hard problem of vehicle routing and scheduling problem with fuzzy time windows and fuzzy goal is formulated and two heuristic algorithms for solving this problem are presented.