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A multiperiod mixed integer programming is presented to minimize the total costs of the logistics network of a firm that sells veterinary products in Colombia. The products are imported through two ports and they are distributed from four distribution centers to the final customers in the country. The model considers the costs of out-of-stocks that occur when the goods are below a minimum safety stock level. Other costs such as costs to open (or to re-open) a facility during the time horizon are also considered. Eight scenarios plus the business-as-is scenario are solved: four scenarios take into account increasing the cost of out-of-stocks and four scenarios consider a decreasing cost trend. The results show that there is an inverse relationship between the cost of inventory and the cost of out-of-stocks. This fact carries strategic modifications in the logistics network of the firm under study. [ABSTRACT FROM AUTHOR]

In this paper, we study facility location problem under many optimization criteria, as minimize the probability of failure and the supply chain total cost. We incorporate account transportation costs, consolidation center cost and reliability of the supply chain. The approach is to design robust supply chains that will be able to absorb negative impacts caused by disruptive events, such as hurricanes, twisters, earthquakes, strikes, accidents, among others. We provide a nonlinear integer-programming model that determines the optimal location of facilities under the criteria of cost and reliability. The proposed model was validated with data obtained from a supply chain of agribusiness sector of Atlantic department in Colombia. The numerical results show an improve of 9.5% in the reliability with an increase of 9.8% on transportation total cost of the supply chain. However, in the proposed model, the companies would not have to incur adequacy costs of consolidation centers, given that current facilities have the capacity to become consolidation center without incurring on significant costs [ABSTRACT FROM AUTHOR]

This paper presents a particular case of the facility location problem. The characteristic of this problem is that it contains a set of clusters or nodes that represent the accumulation of clients who demand a single product. It is desired to locate P distribution centers (DC) where the demand of clusters is only satisfied if we located a distribution center in this cluster. Moreover, the number of capacitated plants and its location must be determined in order to supply the different distributions centers. The objective is to maximize the utility by considering, in one hand, the incomes that are obtained for satisfying the demand of different clusters and in the other hand, the installation costs incurred when locating the Distribution Centers and the plants as well as the costs of material transport from the plants to the distribution center. Other applications of this problem are appreciated in telecommunications networks, electrical networks, etc. The paper also present a new model of integer programming that allows to solve small instances, up to 300 clusters, in an acceptable CPU time, the problems were programmed with AMPL and solved with CPLEX 11.0. For two larger instances the authors present heuristics, which allow obtaining solutions with a GAP least than 1%. [ABSTRACT FROM AUTHOR]

The temporary storage location is a fundamental activity on the hospital solid waste management. The site selection for the location of these stores can not be a trivial task, many factors must be considered, ranging from the rules associated to the proper requirements of the generator. This paper proposes a methodology for selecting these domestic deposits, based on multicriteria techniques (Analytic Hierarchy Process, AHP, and Technique for Order Preference by Similarity to Ideal Solution, TOP-SIS), which compare the opinions of the group decider to select the best alternative of location. For a better understanding of the methodology, we develop a case study in a health center of Santiago de Cali, Colombia. In this case you can see, in addition to the step by step implementation of the methodology, the complementarity of the two techniques used, which strengthen the decision making from the relationships that are formed by the opinions of those involved among the main criteria of assessment and the possible alternatives of location. [ABSTRACT FROM AUTHOR]