solutions by memetic algorithms

The Rural Postman Problem (RPP) is a particular Arc Routing Problem (ARP) which consists of determining a minimum cost circuit on a graph so that a given subset of required edges is traversed. The RPP is an NP-hard problem with significant real-life applications. This paper introduces an original approach based on Memetic Algorithms - the MARP algorithm - to solve the RPP and, also deals with an interesting Industrial Application, which focuses on the path optimization for component cutting operations. Memetic Algorithms are a class of Metaheuristics which may be seen as a population strategy that involves cooperation and competition processes between population elements and integrates “social knowledge”, using a local search procedure. The MARP algorithm is tested with different groups of instances and the results are compared with those gathered from other publications. MARP is also used in the context of various real-life applications

The new global cycle of protest and the portuguese case

This paper focuses on the recent cycle of collective action across countries and continents over the past few years. It seems to be evident that in the outset of 2011 began a new wave of global protests made of contagion and communication that spread in different contexts. Our argument is that, unlike other cycles marked by post-materialistic values, changes in labour and material issues have gained a new centrality. The labour and social basis of these mobilizations is particularly evident, though not exclusive, linking up with disaffection towards political institutions and a crisis of legitimacy of elites in power. We will take the example of the demonstration of 12th March in Portugal as an expression of some of the features in this emerging type of mobilization, where youth plays a leading role. It is from the empirical information concerning this public protest that we will build our analysis, identifying in the Portuguese reality parallels with the international context but also national peculiarities, dynamics of continuity and rupture in relation to the historical past

O Teatro não chega? Uma reflexão sobre arte, inclusão e transformação política

Este trabalho foi publicado em livro financiado por fundos nacionais através da FCT – Fundação para a Ciência e a Tecnologia, I.P., no âmbito do projeto UIDB/04041/2020 (Centro de Estudos Arnaldo Araújo).info:eu-repo/semantics/publishedVersio

Fish brain development in a changing ocean

Tese de mestrado em Ecologia Marinha, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, em 2018Uma das prioridades da Ecologia Marinha relacionada com as alterações climáticas (aquecimento e acidificação dos oceanos) tem sido perceber como as espécies marinhas investem em tecidos cerebrais (ou regiões cerebrais) de modo a adaptarem-se às necessidades cognitivas relevantes para a aptidão ditada pelo ambiente em mudança. Neste contexto, esta dissertação teve como objetivo avaliar os efeitos combinados do aquecimento (Δ 4° C) e acidificação (Δ 700 μatm pCO2 e Δ 0,4 pH) oceânicos no desenvolvimento encefálico (relação massa encéfalo/ massa corporal e crescimento das macro-regiões do encéfalo) de várias espécies juvenis de peixes de diferentes regiões climáticas, a saber: três espécies adaptadas a um ambiente mais estável (tropical) (o peixe-palhaço Amphiprion ocellaris, o orquídea dottyback Pseudochromis fridmani e o neon-goby-azul Elacatinus oceanops), e outras três adaptadas a um ambiente menos estável (sazonal, temperado) (o sargo Diplodus sargus, o linguado Solea senegalensis e a corvina Argyrosomus regius). Os resultados mostram que as espécies temperadas usadas neste estudo são afetadas apenas pela acidificação do oceano, tanto ao nível da totalidade do encéfalo, como de cada macro-região específica, enquanto as espécies tropicais usadas são afetadas pela acidificação dos oceanos, aquecimento dos oceanos e também pela interação entre aquecimento dos oceanos e acidificação dos oceanos. De facto, tanto a totalidade do encéfalo como as macro-regiões encefálicas, exceto o telencéfalo, são afetados de maneira diferente pelas condições futuras de aquecimento dos oceanos e acidificação dos oceanos de acordo com cada espécie. A falta de respostas ao aquecimento dos oceanos pelas espécies temperadas é aqui atribuída à ampla distribuição latitudinal dessas espécies e, portanto, à adaptação a uma faixa de temperatura mais ampla que as espécies tropicais. Curiosamente, todas as interações significativas entre os dois fatores estudados são interações antagonísticas com um mecanismo de tolerância cruzada, o que significa que nessas interações, o peso do cérebro está mais próximo dos níveis das condições controlo do que sob cada um dos fatores separadamente. Possíveis implicações comportamentais e ecológicas desses resultados também são discutidas. Apesar do padrão dicotómico bem definido entre habitats temperados e tropicais, os resultados entre espécies de peixes e macro-regiões encefálicas específicas não exibem um padrão subjacente. Estes diferentes resultados destacam a ideia de respostas fenotípicas específicas de cada espécie em resposta às condições de alterações climáticas futuras.Unravelling how marine species invest in brain tissues (or brain regions) matching the fitness-relevant cognitive demands dictated by a changing environment is a priority in climate change-related (ocean warming and acidification) research. Within this context, this dissertation aimed to assess the combined effects of ocean warming (Δ 4 °C) and acidification (Δ 700 μatm pCO2 and Δ 0.4 pH) in the brain development (brain/body mass ratio and brain macro-region growth) of several juvenile fish species from different climate regions. Namely: three species adapted to a more stable (tropical) environment (clown anemonefish Amphiprion ocellaris, orchid dottyback Pseudochromis fridmani and neon goby Elacatinus oceanops), and other three adapted to a less stable (more seasonal; temperate) environment (seabream Diplodus sargus, flatfish Solea senegalensis and meagre Argyrosomus regius). The results show that the temperate species used in this study are only affected by ocean acidification in both total brain and specific brain regions, while the used tropical species are affected by ocean acidification, ocean warming and also by the interaction of ocean warming and ocean acidification. In fact, both total brain and every brain-region except for Telencephalon are affected by future conditions of ocean warming and ocean acidification differently according to each species. The lack of responses to ocean warming by the temperate species is here attributed to the widespread latitudinal distribution of those species, and thus the adaptation to a wider temperature range than tropical species. Curiously, all the significant interactions between the two studied stressors are antagonistic interactions with a cross-tolerance mechanism, meaning that under those interactions, the brain weight is closer to control levels than under each of the stressors separately. Possible behavioural and ecological implications of those results are also discussed. Despite the distinct dichotomic pattern between temperate and tropical habitats, the results among fish species and specific brain macro-regions do not exhibit a subjacent pattern. These different results highlight the idea of species-specific phenotypic responses to these climate change-related stressors

A new model for location-allocation problem based on sectorization

Many models have been proposed for the location-allocation problem. In this study, based on sectorization concept, we propose a new single-objective model of this problem, in which, there is a set of customers to be assigned to distribution centres (DCs). In sectorization problems there are two important criteria as compactness and equilibrium, which can be defined as constraints as well as objective functions. In this study, the objective function is defined based on the equilibrium of distances in sectors. The concept of compactness is closely related to the accessibility of customers from DCs. As a new approach, instead of compactness, we define the accessibility of customers from DCs based on the covering radius concept. The interpretation of this definition in real life is explained. As another contribution, in the model, a method is used for the selection of DCs, and a comparison is made with another method from the literature, then the advantages of each are discussed. We generate benchmarks for the problem and we solve it with a solver available in Python’s Pulp library. Implemented codes are presented in brief.info:eu-repo/semantics/publishedVersio

A Monte Carlo simulation-based approach to solve dynamic sectorization problem

In this study, two novel stochastic models are introduced to solve the dynamic sectorization problem, in which sectors are created by assigning points to service centres. The objective function of the first model is defined based on the equilibration of the distance in the sectors, while in the second one, it is based on the equilibration of the demands of the sectors. Both models impose constraints on assignments and compactness of sectors. In the problem, the coordinates of the points and their demand change over time, hence it is called a dynamic problem. A new solution method is used to solve the models, in which expected values of the coordinates of the points and their demand are assessed by using the Monte Carlo simulation. Thus, the problem is converted into a deterministic one. The linear and deterministic type of the model, which is originally non-linear is implemented in Python's Pulp library and in this way the generated benchmarks are solved. Information about how benchmarks are derived and the obtained solutions are presented.info:eu-repo/semantics/publishedVersio

Reel and sheet cutting at a paper mill

This work describes a real-world industrial problem of production planning and cutting optimization of reels and sheets, occurring at a Portuguese paper mill. It will focus on a particular module of the global problem, which is concerned with the determination of the width combinations of the items involved in the planning process: the main goal consists in satisfying an order set of reels and sheets that must be cut from master reels. The width combination process will determine the quantity/weight of the master reels to be produced and their cutting patterns, in order to minimize waste, while satisfying production orders. A two-phase approach has been devised, naturally dependent on the technological process involved. Details of the models and solution methods are presented. Moreover some illustrative computational results are included

Visualização de dados médicos em realidade aumentada

Trabalho de projecto de mestrado, Informática, Universidade de Lisboa, Faculdade de Ciências, 2015A Estimulação Magnética Transcraniana é um procedimento médico não invasivo que utiliza estímulos elétricos e magnéticos para tratar problemas neuropsiquiátricos. Nesta técnica são aplicados campos magnéticos sobre uma determinada área da cabeça do paciente para estimular os neurónios nessa área. A área a estimular depende do problema médico a resolver e a sua localização exata no cérebro varia frequentemente de pessoa para pessoa. É, pois, essencial para o médico saber a localização exata da área funcional que pretende estimular. É neste contexto que se pretende intervir com este trabalho, concretizando uma solução que guie o médico durante a execução do procedimento. Aliou-se, então, a Realidade Aumentada e os smartphones para criar uma aplicação móvel que sobrepõe um modelo virtual tridimensional do cérebro sobre a cabeça do paciente. Representa-se o cérebro particionado nas suas áreas anatómicas, para indicar ao médico em que zona deve aplicar a estimulação. Para isso, usam-se marcas semelhantes a códigos QR para rastrear a cabeça do paciente e permitir que os modelos 3D que se obtém, construídos a partir de imagens de ressonância magnética, consigam ser alinhados com a sua cabeça. A solução apresentada inclui também um modo de Realidade Virtual, no qual o utilizador pode interagir com o modelo do cérebro. A visualização pode ser seletiva, permitindo ao utilizador escolher que áreas do cérebro pretende visualizar. O uso do poder computacional recentemente inserido nos dispositivos móveis possibilita esta inovação, com a qual se pretende responder aos problemas reais que os médicos enfrentam ao tentar visualizar o cérebro do paciente, em particular, durante a aplicação da técnica de Estimulação Magnética Transcraniana. A solução proposta tem potencial para poder ser usada noutros contextos.The Transcranial Magnetic Stimulation is a noninvasive medical procedure that uses electric and magnetic stimulation to treat neuropsychiatric problems. In this technique, magnetic fields are applied to a particular area of the head of the patient, to stimulate the neurons in this area. The area that needs to be stimulated depends on the medical condition to be treated and its exact position is not exactly the same for every patient. It is therefore essential for the doctor to know the exact location of the functional area he wants to stimulate. It is in this context that we aim to intervene, implementing a solution to guide the doctor during this procedure. We combined Augmented Reality and smartphones to create a mobile application that overlaps a three-dimensional virtual model of the brain over the patient's head. It represents the brain partitioned in anatomical areas, in order to guide the doctor in the procedure. For this purpose we use markers similar to QR codes to track the patient's head, enabling the correct alignment of the 3D model of the brain with the head. The virtual model of the brain is constructed from magnetic resonance images. The proposed solution also includes a Virtual Reality mode in which the user can interact with the brain model. Besides that, we add a functionality of selective visualization, allowing the user to choose which areas of the brain he wants to visualize. The use of the computational power recently inserted in today's mobile devices enables this innovation, which is intended to respond to the real problems that doctors face when trying to visualize the patient's brain, with uses, in particular, in this technique of Transcranial Magnetic Stimulation. The proposed solution can potentially be used in other contexts