Manuel Figueiredo

Forecasting Household Packaging Waste Generation: A Case Study

Nowadays, house packaging waste (HPW) materials acquired a great deal of importance, due to environmental and economic reasons, and therefore waste collection companies place thousands of collection points (ecopontos) for people to deposit their HPW.

Classification methodology for spare parts management combining maintenance and logistics perspectives

Spare parts management is a function of maintenance management that aims to support maintenance activities, giving real-time information on the available quantities of each spare part and adopting the inventory policies that ensure their availability when required, minimizing costs. The classification of spare parts is crucial to control the vast number of parts that have different characteristics and specificities. Spare parts management involves mainly two areas, maintenance and logistics. Therefore, the integration of both input information is recommended to make decisions. This paper presents a multi-criteria classification methodology combining maintenance and logistics perspectives that intends to differentiate and group spare parts to, subsequently, define the most appropriate stock management policy for each group. The methodology was developed based on a case study carried out in a multi-national manufacturing company and is intended to be included in its computerized maintenance management syste...

Non Emergency Patients Transport - A Mixed Integer Linear Programming

Fundacao para a Ciencia e Tecnologia; project GATOP - Genetic Algorithms for Team Orienteering Problem (Ref PTDC/EME- GIN/120761/2010), financed by national funds by FCT / MCTES, and co-funded by the European Social Development Fund (FEDER) through the COMPETE - Programa Operacional Fatores de Competitividade (POFC) Ref FCOMP-01-0124- FEDER-020609. This work has been partially supported by FCT – Fundacao para a Ciencia e Tecnologia within the Project Scope: PEst-OE/EEI/UI0319/2014 The authors would like to thank the NEOS Server at the University of Wisconsin in Madison for providing support to this study

Household packaging waste management

Household packaging waste (HPW) has an important environmental impact and economic relevance. Thus there are networks of collection points (named “ecopontos” in Portugal) where HPW may be deposited for collection by waste management companies.

The Non-Emergency Patient Transport Modelled as a Team Orienteering Problem

This work presents an improved model to solve the non-emergency patients transport (NEPT) service issues given the new rules recently established in Portugal. The model follows the same principle of the Team Orienteering Problem by selecting the patients to be included in the routes attending the maximum reduction in costs when compared with individual transportation. This model establishes the best sets of patients to be transported together. The model was implemented in AMPL and a compact formulation was solved using NEOS Server. A heuristic procedure based on iteratively solving Orienteering Problems is presented, and this heuristic provides good results in terms of accuracy and computation time. Euclidean instances as well as asymmetric real data gathered from Google maps were used, and the model has a promising performance mainly with asymmetric cost matrices.

Genetic algorithms for the non emergency patients transport service

This study presents three genetic algorithms developed to solve a routing problem related with a transportation service for nonemergency patients in Portugal. A model based on an extension of the Team Orienteering Problem was developed to carry out several legal constraints. The results of computational experiments made to validate the adopted methodology, using both public TOP instances and real data, are presented.