Evolution of Swarm Robotics Systems with Novelty Search

Novelty search is a recent artificial evolution technique that challenges traditional evolutionary approaches. In novelty search, solutions are rewarded based on their novelty, rather than their quality with respect to a predefined objective. The lack of a predefined objective precludes premature convergence caused by a deceptive fitness function. In this paper, we apply novelty search combined with NEAT to the evolution of neural controllers for homogeneous swarms of robots. Our empirical study is conducted in simulation, and we use a common swarm robotics task - aggregation, and a more challenging task - sharing of an energy recharging station. Our results show that novelty search is unaffected by deception, is notably effective in bootstrapping the evolution, can find solutions with lower complexity than fitness-based evolution, and can find a broad diversity of solutions for the same task. Even in non-deceptive setups, novelty search achieves solution qualities similar to those obtained in traditional fitness-based evolution. Our study also encompasses variants of novelty search that work in concert with fitness-based evolution to combine the exploratory character of novelty search with the exploitatory character of objective-based evolution. We show that these variants can further improve the performance of novelty search. Overall, our study shows that novelty search is a promising alternative for the evolution of controllers for robotic swarms.Comment: To appear in Swarm Intelligence (2013), ANTS Special Issue. The final publication will be available at link.springer.co

Organisational maturity and information systems and technology projects in healthcare: the mediation of project management.

Doutoramento em GestãoThe challenges that health organisations face today is to get better organisational performance, reliable information, faster quality services at prices that should be affordable to the entire population. To fulfil this important goal, health organisations require more comprehensive and integrated approaches such as, but not limited to, optimise their available resources, eliminate inefficiencies and achieve the planned benefits from investments in Information Systems and Technology (IS/IT). Healthcare organisations must improve their management practices and internal procedures to answer the increasing demand of managers, health professionals and the public in general, for more and better information. Health organisations adopt a patient-centred care approach and invest massively in IS/IT, hoping that these investments will improve medical care and patient needs. The main objective of our research is to analyse how the Organisational Maturity affect IS/IT Project Success in Healthcare and if that success is enhanced by using Project Management practices. There is evidence that there is a direct relationship between these variables and that Project Management practices can mediate it, helping to increase the effectiveness of IS/IT projects. Furthermore, the application of the Project Management practices can also improve confidence that the results of these investments meet stakeholders’ expectations, both by the benefits accomplishment and by adding a perceived value to organisations. This study develops and validates an instrument to analyse the data collected from a survey to professionals’ perceptions about the IS/IT Project Success in Healthcare organisations. The results confirm that Project Management has a mediating effect on the relationship between Organizational Maturity and success of IS/IT projects and higher levels of Organisational Maturity will generate more successfully IS/IT projects, although the presence of the mediator Project Management can, in specific situations, affect negatively the correlation between Organisational Maturity and IS/IT Project Success.Os desafios que enfrentam atualmente as organizações de saúde estão diretamente relacionados com o fato de ambicionarem um melhor desempenho, mais e melhor informação de saúde, serviços de qualidade mais céleres. a custos acesíveis à maioria da população. Para o total cumprimento deste desiderato as organizações de saúde têm investido em soluções tecnológicas mais abrangentes e integradas de forma a otimizar os recursos disponíveis, eliminar ineficiências e atingir os benefícios plenos dos investimentos em Sistemas e Tecnologias da Informação (SI/TI). As organizações de saúde procuram melhorar as suas práticas de gestão para dar resposta a uma crescente procura de informação de saúde por parte de gestores, profissionais e público em geral. As organizações de saúde adotaram uma abordagem centrada no paciente e realizaram significativos investimentos em SI/TI na expetativa de que estes trouxessem melhorias ao nível assistencial e na satisfação das expetativas dos seus utilizadores. O principal objetivo deste trabalho é analisar como a Maturidade Organizacional afeta o sucesso do projeto em SI/TI em saúde e se esse sucesso é potenciado pela utilização de práticas de gestão de projetos. Há evidências da existência de uma relação direta entre esstas duas variáveis e que as práticas de Gestão de Projetos a podem mediar, ajudando a aumentar a eficácia dos projetos de SI/TI. Além disso, a aplicação das práticas de Gestão de Projetos podem melhorar a confiança nos resultados dos investimentos e atender às expectativas das diferentes partes interessadas, tanto pela realização de benefícios quanto pela criação de valor percebido para as organizações. Este estudo analisa os dados recolhidos de um questionário à perceção dos profissionais sobre o sucesso dos projetos IS/IT nas organizações de saúde. Os resultados obtidos confirmam. Os resultados confirmam que o Gestão de Projetos tem um efeito mediador na relação entre Maturidade Organizacional e Sucesso de Projetos de SI/TI e níveis mais elevados de Maturidade Organizacional gerarão projetos SI/TI mais bem-sucedidos, embora a presença do mediador Gestão de Projetos, possa, em circunstâncias específicas situações, afetar negativamente a correlação entre as duas variáveis.N/

Generalized Solutions of a Nonlinear Parabolic Equation with Generalized Functions as Initial Data

In \cite{bf} Br\'ezis and Friedman prove that certain nonlinear parabolic equations, with the $\delta$-measure as initial data, have no solution. However in \cite{cl} Colombeau and Langlais prove that these equations have a unique solution even if the $\delta$-measure is substituted by any Colombeau generalized function of compact support. Here we generalize Colombeau and Langlais their result proving that we may take any generalized function as the initial data. Our approach relies on resent algebraic and topological developments of the theory of Colombeau generalized functions and results from \cite{A}

Proposta de clausulado normativo para o traçado de intersecções em estradas nacionais.

Tese de mestrado integrado. Engenharia Civil - Especialização em Vias de Comunicação. Universidade do Porto. Faculdade de Engenharia. 201

Merging traditional livelihood activities with new employment opportunities brought by ecotourism to Iona national park, Angola: rethinking social sustainability

Ecotourism activities and investment projects have been consistently increasing worldwide over the last few decades. In this process, ecotourism has contributed to fight poverty, to create local employment opportunities and to promote nature conservation. However, there are also plenty examples of nature-base tourism destinations where ecotourism principles have been distorted and negative impacts are on the rise. Therefore, studies that provide a deep understanding of the roots and consequences of those both positive and negative impacts are needed to achieve new higher tourism quality standards, to foster a sound local development and to promote an integrated and sustainable national growth. To obtain information useful to contribute specific recommendations aimed at linking tourism employers and job seekers, we have conducted a survey addressing locals’ demographic characteristics and their engagement in traditional livelihood activities. Data gathered from 202 respondents showed that in the largest villages traditional livelihood activities, excepting pastoralism, tend to have little expression while the same activities seem to play a key role in some small communities. Striking differences were found between nomadic or semi-nomadic people and people who have been assimilated into the western civilization and also have more sedentary life styles. Using this information and taking in consideration some new employment opportunities brought nature-based tourism to the Iona National Park, we have identified specific demographic profiles more suited for part-time and full-time jobs

O contrato de crédito ao consumo enquanto mútuo de escopo

Dissertação apresentada à Faculdade de Direito da Universidade de Coimbra conducente ao grau de Mestre em Direito, especialidade em Ciências Jurídico-forense

Luminescent compounds with Delayed Fluorescence in Aggregate State for Imaging Applications

Visual stimulation through colour is one of the most powerful tools to get and process information easily. In the world of chemical compounds, this type of knowledge could be reached using fluorescence. However, a major disadvantage of this process is its small lifetime that can limit, for example, the local cell-imaging information using conventional fluorescent probes. To overcome this problem, TADF (Thermally Activated Delayed Fluorescence) com pounds are a possible solution since their lifetime range could reach micro- or even milliseconds. TADF compounds were firstly recognized for their ability to maximize internal quantum efficiency of OLEDs but now they are also known for their capacity of bioluminescent probing. The major concerns of using TADF compounds in biologic systems are their low solubility, low biocompatibility, poor efficiency in polar media and high susceptibility to oxygen in triplet state. Therefore, we designed a series of com pounds which can exhibit TADF in the aggregate state - Aggregation Induced Delayed Fluorescence (AIDF), as a possible solution to overcome these limitations. For the aim of this work, Diphenyl sulfoxide-based and Quinoxaline-based units acceptors and its relatives were synthetised with success. Diphenyl sulfoxide derivatives were confirmed unstable towards fluorescence irradia tion. As a consequence of that, TADF was not able to be confirmed. However, diphenyl sulfoxide derivatives have shown signs of AEE (Aggregation enhanced emission). Nonetheless, the presence of aggregate states has been observed. A quinoxaline deriva tive was also studied. In this case, the TADF and aggregate states phenomenons have been experimentally verified. And, instead of AIE-TADF, AEE-TADF was confirmed.A estimulação visual através da cor é uma das ferramentas mais poderosas para obter e processar informação com facilidade. Na área da química, esse tipo de conhecimento pode ser alcançado por meio da fluorescência. No entanto, uma grande desvantagem deste processo, quando aplicado em bioimagiologia, é o seu curto tempo de vida que pode reduzir a resolução e sensibilidade. Para superar esse problema, os compostos com fluorescência retardada ativada por temperatura (TADF - Thermally Activated Delayed Fluorescence) são uma solução possível, uma vez que o seu tempo de vida útil pode chegar até aos milissegundos, possibilitando a utilização de técnicas resolvidas no tempo. As principais limitações do uso de compostos TADF em sistemas biológicos são sua baixa solubilidade, baixa biocompatibilidade, baixa eficiência em meios polares e alta suscetibilidade ao oxigénio. Deste modo, projetámos uma série de compostos que podem apresentar TADF no estado agregado - Aggregation Induced Delayed Fluorescence (AIDF) -, como uma possível solução para contornar essas limitações. Para atingir os objetivos deste trabalho, utilizaram-se as unidades aceitadoras de difenil sulfóxido e quinoxalina para fazer novas famílias de compostos, recorrendo às unidades doadoras carbazole, acetamidaindole e fenoxazina. Confirmou-se que os compostos derivados da unidade aceitadora difenil sulfóxido se degradavam quando expostos a uma irradiação UV. No entanto, foi observada a presença de estados agregados - fenómeno de Aggregation Enhanced emission. Um derivado da quinoxalina, contendo duas unidades de carbazole como doador, também foi estudado. Neste composto foi possível verificar a presença de fluorescência retardada, bem como a presença de estados agregados através das técnicas de espetroscopia de absorção UV-Vis e de fluorescência (em estado estacionário e resolvida no tempo), e também utilizando fotólise flash induzida por laser