A Memetic Algorithm for a Bi-objective Bus Driver Rostering Problem

The Bus Driver Rostering Problem (DRP) consists of assigning bus drivers to daily duties during a planning period. The problem considers hard constraints imposed by institutional and legal requirements. Solutions should as much as possible satisfy soft constraints that qualify rosters according to either the company's or the drivers' interests. A bi-objective version of the DRP is considered and two models are presented. Due to the high computational complexity of DRP, this paper proposes the Strength Pareto Utopic Memetic Algorithm (SPUMA) a new heuristic algorithm specially devised to tackle the problem. SPUMA genetic component combines utopic elitism with a strength Pareto fitness evaluation and includes an improvement procedure. Computational results show that SPUMA outperforms an adaptation of one of the state-of-the-art most competitive multi-objective evolutionary algorithms, SPEA2

Bi-objective Evolutionary Heuristics for Bus Drivers

The Bus Driver Rostering Problem refers to the assignment of drivers to the daily schedules of the company's buses, during a planning period of a given duration. The drivers' schedules must comply with legal and institutional rules, namely the Labour Law, labour agreements and the company's specific regulations. This paper presents a bi-objective model for the problem and two evolutionary heuristics differing as to the strategies adopted to approach the Pareto frontier. The first one, the utopian strategy, extends elitism to include an unfeasible solution in the population, and the second one is an adapted version of the well known SPEA2 (Strength Pareto Evolutionary Algorithm). The heuristics' empirical performance is studied with computational tests on a set of instances generated from vehicle and crew schedules. This research shows that both methodologies are adequate to tackle the instances of the Bus Driver Rostering Problem. In fact, in short computing times, they provide the planning department, with several feasible solutions, rosters that are very difficult to obtain manually and, in addition, identify among them the efficient solutions of the bi-objective model

A decomposition approach to the integrated vehicle-crew-rostering problem

The problem addressed in this paper is the integrated vehicle-crew-rostering problem (VCRP) aiming to define the schedules for the buses and the rosters for the drivers of a public transit company. The VCRP is described by a bi-objective mixed binary linear programming model with one objective function aggregating vehicle and crew scheduling costs and the other the rostering features. The VCRP is solved by a heuristic approach based on Benders decomposition where the master problem is partitioned into daily integrated vehicle-crew scheduling problems and the sub-problem is a rostering problem. Computational experience with data from a bus company in Lisbon shows the ability of the decomposition approach for producing a variety of potentially efficient solutions for the VCRP within low computing times

Solving Public Transit Scheduling Problems

Operational planning within public transit companies has been extensively tackled but still remains a challenging area for operations research models and techniques. This phase of the planning process comprises vehicle scheduling, crew scheduling and rostering problems. In this paper, a new integer mathematical formulation to describe the integrated vehicle-crew-rostering problem is presented. The method proposed to solve this multi-objective problem is a sequential algorithm considered within a preemptive goal programming framework that starts from the solution of an integrated vehicle and crew scheduling problem and ends with the solution of a driver rostering problem. Feasible solutions for the vehicle and crew scheduling problem are obtained by combining a column generation scheme with a branch-and-bound method. These solutions are the input of the rostering problem, which is tackled through a mixed binary linear programming approach. An application to real data of a Portuguese bus company is reported and shows the importance of integrating the three scheduling problems

Patologia e reabilitação de revestimentos de fachadas

Dissertação de mestrado em Engenharia Civil (área de especialização em Materiais, Reabilitação e Sustentabilidade da Construção)O presente trabalho pretendeu relacionar manifestações de patologia com os diferentes tipos de revestimento exterior de fachada. Nesse sentido, foi efectuado um levantamento de manifestações de patologia, com especial enfoque para os revestimentos de pintura e cerâmicos, tendo-se, posteriormente, definido uma área territorial (cidade de Valpaços), onde foi efectuada uma caracterização do edificado existente. De entre 64 edifícios multifamiliares analisados no território estudado, foram seleccionados 5 edifícios, nos quais recaiu um estudo mais detalhado, onde, para além de identificar as anomalias existentes, procurou definir-se uma metodologia de reabilitação/restauro conservativa salvaguardando a funcionalidade e o aspecto estético da fachada exterior dos mesmos. Denotou-se que as manifestações patológicas averiguadas nas fachadas dos edifícios, advêm sobretudo de uma falta de qualidade do projecto, dos materiais e de uma mãode- obra deficiente, aliados a uma inexistente manutenção preventiva e reparativa, o que contribui para a sua crescente degradação. Verificou-se também que a fissuração e o descolamento do revestimento foram as principais anomalias encontradas e as causas resultam sobretudo de um não tratamento adequado na transição de elementos com funções distintas (ligações laje/alvenaria) e a problemas decorrentes de infiltrações. Este trabalho contempla ainda, numa fase posterior, um conjunto de recomendações, que norteiam na definição de soluções para a reabilitação de fachadas de edifícios correntes, consoante o tipo de revestimento, de forma a se garantir que as mesmas asseguram resultados satisfatórios a longo prazo.This study intended to relate manifestations of pathology with the different types of exterior coating of facade. In this way, a survey of manifestations of pathology was carried out, with special focus to the coatings of paint and ceramics, having subsequently been defined a territorial area (city of Valpaços) in which a characterization of the existing buildings was made. Among 64 residential buildings with multiple floors examined in the studied territory, 5 were selected, in which a more detailed study was carried out, where, besides identifying the existing anomalies, a methodology for conservative rehabilitation/restoration was sought safeguarding the functionality and the aesthetic aspect of the exterior facade of the buildings. It was shown that the pathological manifestations checked in the facades of the buildings result, above all, from a lack of quality in design, materials and a deficient workmanship, allied with a non-existent preventive and reparative maintenance, which contributed to its increasing degradation. It was also verified that the cracking and displacement of the coating were the main anomalies found and the causes result especially from non-suitable treatment in the transition of elements with distinct functions (connection between flagstone and masonry) and problems resulting from infiltrations. This study also includes, in a subsequent stage, a set of recommendations that guide us in the definition of solutions for the rehabilitation of facades of common buildings, according to the type of coating, in order to ensure that these provide satisfactory results at long term

Clitic omission and clitic placement in French-Portuguese bilingual children

UID/LIN/03213/2013 PD/BD/113973/2015publishersversionpublishe

Cancro ginecológico – protocolos de diagnóstico e terapêutica

O Instituto Português de Oncologia de Francisco Gentil – Centro Regional Oncológico de Lisboa S.A acolhe anualmente cerca de mulheres portadoras de Cancro Ginecológico. O Serviço de Ginecologia tem, desde a sua criação, fomentado a existência de um Grupo Multidisciplinar dos Tumores Ginecológicos que engloba não só os Ginecologistas como Oncologistas Médicos, Radioterapeutas Oncológicos, Anátomo-Patologistas, Imagiologistas e outros Especialistas com competência em Oncologia Ginecológica. A Comissão de Protocolos de Diagnóstico e de Terapêutica é a emanação prática desta filosofia. Assim, a revisão e actualização dos Protocolos elaborados por esta Comissão e agora publicados traduzem a metodologia usada no Serviço e baseiam-se nos protocolos de Instituições Oncológicas Internacionais de referência e na experiência acumulada na nossa Instituição, considerando a capacidade técnica e meios materiais existentes. Pretendem, tanto quanto possível, uniformizar procedimentos e agilizar a colaboração com todas as Instituições que nos referenciam as suas doentes, tendo como fim último o tratamento correcto do Cancro Ginecológico, com um aproveitamento racional dos recursos humanos e técnicos

Sustentabilidade na construção : comportamento térmico de edifícios em Portugal usando materiais de mudança de fase

Tese de doutoramento. Engenharia Civil. Faculdade de Engenharia. Universidade do Porto. 201

Durabilidade de cimentos-cola em revestimentos cerâmicos aderentes a fachadas

Tese de mestrado. Faculdade de Engenharia. Universidade do Porto. 199