INTRODUCTION Androgen deprivation therapy (ADT) with gonadotropin-releasing hormone (GnRH) analogs is a standard treatment for advanced prostate cancer. GnRH analog therapy can reduce testosterone to "castrate" levels, historically defined as <50 ng/dL. With the advent of newer assays, a lower threshold of <20 ng/dL has recently been proposed. We report the results of a retrospective analysis o...

This paper introduces a new routing problem referred to as the vehicle routing problem with vector profits. Given a network composed of nodes (depot/sites) and arcs connecting the nodes, the problem determines routes that depart from the depot, visit sites to collect profits, and return to the depot. There are multiple stakeholders interested in the mission and each site is associated with a ve...

Sir: Oral risperidone is an effective and well-tolerated atypi-cal antipsychotic 1 that has been in widespread clinical usage for over 10 years. In recent years, a long-acting injectable form of depot risperidone with a delivery system different from other depot antipsychotics became available in the United States following several years of marketing in other countries. This formulation consist...

Multi-depot routing problems arise in distribution logistics where a set of vehicles based at several depots are used to serve a number of clients. Most variants of this problem have the basic requirement that the route of each vehicle starts and ends at the same depot. This paper describes new inequalities, namely multicut constraints (MCC), that enforce this requirement in mathematical progra...

We address the logistics and planning problem of delivering Ready Mixed Concrete (RMC) to a set of demand customers from a single depot while respecting time-windows induced restrictions. The RMC Dispatching Problem (RMCDP) is closely related to the Vehicle Routing Problem (VRP) with the difference that demand nodes in the RMCDP may be visited more than once by a truck. This class of routing an...

In this paper a new formulation is presented for optimally solving single depot Ready Mixed Concrete (RMC) with a homogeneous fleet. Most introduced models in the literature deal with individual deliveries; however, the proposed model is based on customers’ specifications. This results in a reduction in the number of constraints as well as in the number of variables. Therefore, the solution spa...

In this work, the capacitated location-routing problem with simultaneous pickup and delivery (CLRP-SPD) is considered. This problem is a more realistic case of the capacitated location-routing problem (CLRP) and belongs to the reverse logistics of the supply chain. The problem has many real-life applications of which some have been addressed in the literature such as management of liquid petrol...

This paper presents a unified exact method for solving an extended model of the well-known Capacitated Vehicle Routing Problem (CVRP), called the Heterogenous Vehicle Routing Problem (HVRP), where a mixed fleet of vehicles having different capacities, routing and fixed costs is used to supply a set of customers. The HVRP model considered in this paper contains as special cases: the Single Depot...

Motivated by the spare parts distribution system of a major automotive manufacturer in Turkey, we consider a multicommodity distribution problem from a central depot to a number of geographically dispersed demand points. The distribution of the items is carried out by a set of identical vehicles. The demand of each demand point can be satisfied by several vehicles and a single vehicle is allowe...