A framework for robustness assessment in the context of corroded RC structures

Structural robustness is an emergent concept related to the structural response to damage. At the present time, robustness is not well defined and much controversy still remains around this subject. Even if robustness has seen growing interest as a consequence of catastrophic consequences due to extreme events, the fact is that the concept can also be very useful when considered on more probable exposure scenarios such as deterioration, among others. This paper intends to be a contribution to the definition of structural robustness, especially in the analysis of reinforced concrete structures subjected to corrosion. To achieve this, first of all, several proposed robustness definitions and indicators and misunderstood concepts will be analyzed and compared. From this point and regarding a concept that could be applied to most type of structures and dam-age scenarios, a robustness definition is proposed. To illustrate the proposed concept, an example of corroded reinforced concrete structures will be analyzed using nonlinear analysis numerical methods based on a contin-uum strong discontinuities approach and isotropic damage models for concrete. Finally the robustness of the presented example will be assessed.

Geodupa - a geography-driven partial membership algorithm

Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia Informática

Question order and context effects on multi-items scales questions

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação

Decision-making process in radiology: the magnetic resonance example in the TA context

Based on the report for “Project IV” unit of the PhD programme on Technology Assessment (Doctoral Conference) at Universidade Nova de Lisboa (December 2011). This thesis research has the supervision of António Moniz (FCT-UNL and ITAS-KIT) and Michael Decker (Karlsruhe Institute of Technology-ITAS). Other members of the thesis committee are Carlos Alberto da Silva (University of Évora), José Maria de Albuquerque (Institute of Welding and Quality), Lotte Steuten (University of Twente), Mário Forjaz Secca (FCT-UNL) and Nelson Chibeles Martins (FCT-UNL).

Algorithm for the Parkinson’s disease behavioural models characterization using a biosensor

Dissertação para obtenção do Grau de Mestre em Engenharia Biomédica

Context-aware personalization environment for mobile computing

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Organizational culture influence on information quality - use of business intelligence systems relationship: portuguese context

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação

Mobilie Banking adoption: a novel in the portuguese context

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação

The integration of online advertising: The effects of source expertise and certainty level of the message on consumer involvement and persuasion in the context of user-generated advertising

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

A new opportunity for human resources management to create value: Shaping a new business paradigm in the context of the Portuguese hotel industry

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Improvements on the KNN classifier

Dissertação para obtenção do Grau de Mestre em Engenharia Informática

Rastreio combinado do 1º trimestre e doenças autoimunes : Impacto das variaveis pré-analíticas na avaliação do risco

RESUMO: Contexto: As anomalias congénitas, com particular destaque para as neuploidias , afectam aproximadamente 2% dos recém-nascidos, constituindo causas frequentes de morbilidade e mortalidade. Actualmente, a avaliação do grau de risco para as aneuploidias mais prevalentes (T21, T13, T18) é efectuada através do “Rastreio Combinado do 1º Trimestre”, devendo as grávidas com risco acrescido ser sujeitas a exames invasivos (ex.biópsia das vilosidades coriónicas,amniocentese). Quanto mais qualidade existir num rastreio, menos falsos positivos existirão e menor o número de exames diagnósticos invasivos desnecessários. As doenças autoimunes são doenças inflamatórias crónicas em cuja fisiopatologia se encontram distúrbios da imunidade humoral e celular, dependentes de factores genéticos, hormonais,psicológicos e ambientais. Atingem mais o sexo feminino e durante a idade fértil,podendo influenciar o outcome da gravidez e a saúde neonatal causando significativa morbilidade e mortalidade. O lúpus eritematoso sistémico para além de potencialmente afectado pelas alterações imunoendócrinas fisiológicas da gravidez, associa-se frequentemente a problemas de fertilidade. Recentemente, foi sugerido que as anormalidades ocorridas durante a invasão precoce do sinciciotrofoblasto, resultando em deficiente diferenciação, deficiente maturação e diminuição na produção de hCG, poderão ser o mecanismo fisiopatológico primário para as perdas fetais no primeiro trimestre, nos doentes com SLE. A ocorrência de níveis elevados de hCG total e ß-hCG livre no rastreio para despiste de síndrome de Down do segundo e do primeiro trimestre foi assinalada em grávidas portadoras de lúpus, mas a escassez de estudos comprovativos e a pequena dimensão das amostras estudadas constituiu uma limitação significativa na fidedignidade dos resultados obtidos. Objectivos: O estudo teve como objectivos i. estabelecer valores normativos Portugueses e de distribuição para as MoM’s dos parâmetros séricos do primeiro trimestre, por semana de gestação:(PAPP-A e ß-hCG livre), ii. avaliar a influência que as doenças autoimunes têm sobre as MoM’s individuais dos parâmetros bioquímicos PAPP-A e/ou ß-hCG livre, utilizados no rastreio pré-natal combinado do 1º trimestre, e iii. saber se as doenças autoimunes podem condicionar um aumento da taxa de resultados falsos positivos, com consequente aumento do número de amniocenteses. Metodologia: Estudo longitudinal prospectivo, consistindo num rastreio pré-natal combinado de 1º trimestre para pesquisa de aneuploidias, em duas amostras provenientes do Reino Unido (n= 45,854) e de Portugal (n=3122). Foram avaliados parâmetros socio-demográficos, ecográficos, laboratoriais, e calculados os indicadores de desempenho do rastreio combinado. A execução analítica dos testes bioquímicos séricos (PAPP-A e ß-hCG livre) foi realizada no autoanalisador Brahms Kryptor e no autoanalizador 6000 Delfia Xpress. Compararam-se os grupos autoimune e não autoimune das amostras. Resultados: Relativamente às características populacionais, o grupo auto imune tinha valores significativamente superiores nas variáveis idade materna e idade gestacional. Comparando os grupos com e sem doença autoimune, constatou-se a existência de uma elevação das MoM’s da ß-hCG livre nas grávidas com doença autoimune, nomeadamente nos casos de lúpus eritematoso sistémico. Conclusões: os resultado obtidos reforçam a indicação do rastreio combinado do 1º trimestre certificado pela FMF nas grávidas com doenças autoimunes, nomeadamente para as doentes com LES; no entanto, devem ser calculados e introduzidos factores de correcção no algoritmo de risco, de modo a evitar a subida no número de resultados falso-positivos, e consequentemente a sobre- utilização de métodos invasivos.------------ ABSTRACT: Context: Congenital anomalies, with particular reference to aneuploidias, affect approximately 2% of newborns, and are frequent causes of morbidity and mortality. Currently, the risk evaluation for the most prevalent aneuploidias (T21, T13, T18) is carried out through the “combined first trimester screening”, and pregnant women with increased risk are subjected to invasive tests (e.g. villus biopsy done, amniocentesis). The more quality exists in a screening, less false positives exists and fewer unnecessary invasive diagnostic exams. Autoimmune diseases are chronic inflammatory diseases in whose pathophysiology are immune humoral and cellular disorders, dependent on genetic factors, hormonal, psychological and environmental factors. The disease is more prevalent among females, during the child-bearing age, and may influence the outcome of pregnancy and neonatal health causing significant morbidity and mortality. Lupus Erythematosus in addition to potentially affected by immunoendocrine physiological changes of pregnancy, is often associated with fertility problems. Recently, it has been suggested that the abnormalities that occurred during the early invasion of the syncytiotrophoblast, resulting in insufficient differentiation, deficient maturation and decrease in production of hCG may be the primary pathophysiological mechanism for fetal losses in the first quarter, in patients with SLE. The occurrence of elevated levels of total hCG and free ß-hCG in screening for Down’s syndrome of the second and first trimester was reported in pregnant women with lupus, but the paucity of supporting studies and the small size of the samples studied constituted a significant limitation on the trustworthiness of the results obtained. Objectives: this study aims to i. establish normative values for the serum parameters MoM’s (PAPP-A and free β-hCG) and it’s distribution, in the first trimester, by week of pregnancy; ii. assess the influence that the autoimmune diseases have on the MoM’s of individual biochemical PAPP-A and/or β-hCG, used in antenatal screening combined for the first trimester, and iii. whether the autoimmune diseases may make an increased rate of false positives, with consequent increase in the number of amniocenteses.Methodology: Prospective longitudinal study, consisting of a combined first trimester antenatal screening for aneuploidies lookup in two samples from the United Kingdom (n=45.854) and Portugal (n= 3.122). Socio-demographic, echographic and laboratory parameters were evaluated, and combined screening performance indicators were calculated. The analytical run of serum biochemical tests (PAPP-A and ß-hCG) was held at the Brahms Kryptor and in Delfia Xpress 6000. Comparisons between autoimmune group and non-autoimmune group were made. Results: Relating to population characteristics, the autoimmune group had significantly diferente values in the variables maternal age and gestational age. Comparing the groups with and without autoimmune disease, it was noted that there is an elevation of the MoM’s of free ß-hCG levels in pregnant women with autoimmune disease, particularly in cases of systemic lupus erythematosus. Conclusions: The results obtained reinforce the indication of FMF certified combined screening in pregnant women with autoimmune diseases, notably to the patients with SLE; However, correction factors should be calculated and entered in the risk algorithm, in order to avoid the rise in the number of false positive results, and consequently the over-use of invasive methods.

Developing clinical trials in the portuguese family medicine : challenges and opportunities in the European context

RESUMO: Introdução: A hipótese colocada nesta tese é a de que poderia haver um número bastante mais elevado de ensaios clínicos na medicina familiar portuguesa se os obstáculos fossem removidos e as oportunidades exploradas de modo adequado. Contexto: Em Portugal existe uma nova geração de Médicos de Família que está a assumir postos de trabalho um pouco por todo o país e que é aceite como sendo a mais bem preparada geração de sempre. Métodos: Busca na MEDLINE. Leitura de artigos na única publicação científica dedicada à Medicina Geral e Familiar – RPMGF. Consulta em livros portugueses de política da saúde e acerca do Plano Nacional de Saúde. O INFARMED foi contactado e relatórios seus sobre ensaios clínicos foram analisados. Os Médicos de Família portugueses foram contactados e convidados a responder a questionários. Além disso, quinze personalidades da Medicina Portuguesa foram chamadas a sugerir soluções. Resultados: De acordo com dados do INFARMED, de 2006 a 2011 houve apenas quatro centros de saúde envolvidos em ensaios clínicos. Em Portugal: Existe um número pouco significativo de ensaios académicos; Praticamente não há infraestruturas de suporte ou treino; Os registos clínicos eletrónicos são usados de forma ineficiente; a investigação é fracamente ligada às carreiras médicas; há isolamento interno e externo; a já complexa regulamentação da União Europeia é complicada ainda mais; há um subfinanciamento da Investigação Clínica. Os Médicos de Família portugueses estão disponíveis para participar ativamente numa mudança. Discussão: Com os presentes resultados o diagnóstico para a presente situação é claramente negativo. Felizmente existem muito boas oportunidades para melhorar. Conclusão/Recomendações: Tempo, dinheiro e apoio têm de ser fornecidos aos Médicos de Família portugueses. É nesse sentido que são fornecidas vinte recomendações para obter uma verdadeira mudança no panorama dos Ensaios Clínicos na Medicina Familiar portuguesa.-------------ABSTRACT: Introduction: The hypothesis of this thesis is that there could be a much greater number of Clinical Trials in Portuguese Family Medicine if obstacles were removed and opportunities explored properly. Background: In Portugal there is a new generation of Family Doctors that is assuming permanent positions all over the country and is accepted to be the most well prepared generation ever. Methods: Search on MEDLINE. Relevant articles were also identified in the only jornal dedicated to Portuguese Family Medicine, RPMGF. A search was made on Portuguese health policy textbooks and national health plan policy. INFARMED was also contacted and their reports about Clinical Trials were analysed. Portuguese Family Doctors themselves were contacted and invited to answer questionnaires. Besides that, fifteen key opinion leaders related to Portuguese Medicine were approached for solutions. Results: According to INFARMED data, from 2006 to 2011 there were only four health centres involved in clinical trials. In Portugal there is: A negligible number of academic trials; almost no support infrastructures or training; inefficiently used electronic health records; a research weakly linked to medical careers; an uninformed isolation internally and externally; an already complex European Union regulation that is compounded even more; Scarce funding for clinical research. Portuguese Family Doctors are keen to actively participate in a change. Discussion: With the present results the diagnosis for the current situation is clearly negative. Fortunately there are very good opportunities to improve. Conclusion/Recommendations: Time, money and support must be given to Portuguese Family Doctors. In this context, twenty recommendations are provided intending to promote a true change in Portuguese Family Medicine Clinical Trials panorama.

Context-based identification of energy consumption in industrial plants

Nowadays, reducing energy consumption is one of the highest priorities and biggest challenges faced worldwide and in particular in the industrial sector. Given the increasing trend of consumption and the current economical crisis, identifying cost reductions on the most energy-intensive sectors has become one of the main concerns among companies and researchers. Particularly in industrial environments, energy consumption is affected by several factors, namely production factors(e.g. equipments), human (e.g. operators experience), environmental (e.g. temperature), among others, which influence the way of how energy is used across the plant. Therefore, several approaches for identifying consumption causes have been suggested and discussed. However, the existing methods only provide guidelines for energy consumption and have shown difficulties in explaining certain energy consumption patterns due to the lack of structure to incorporate context influence, hence are not able to track down the causes of consumption to a process level, where optimization measures can actually take place. This dissertation proposes a new approach to tackle this issue, by on-line estimation of context-based energy consumption models, which are able to map operating context to consumption patterns. Context identification is performed by regression tree algorithms. Energy consumption estimation is achieved by means of a multi-model architecture using multiple RLS algorithms, locally estimated for each operating context. Lastly, the proposed approach is applied to a real cement plant grinding circuit. Experimental results prove the viability of the overall system, regarding both automatic context identification and energy consumption estimation.

Diffusional kurtosis imaging using a fast heuristic constrained linear least squares algorithm: a plugin for OsiriX

Diffusion Kurtosis Imaging (DKI) is a fairly new magnetic resonance imag-ing (MRI) technique that tackles the non-gaussian motion of water in biological tissues by taking into account the restrictions imposed by tissue microstructure, which are not considered in Diffusion Tensor Imaging (DTI), where the water diffusion is considered purely gaussian. As a result DKI provides more accurate information on biological structures and is able to detect important abnormalities which are not visible in standard DTI analysis. This work regards the development of a tool for DKI computation to be implemented as an OsiriX plugin. Thus, as OsiriX runs under Mac OS X, the pro-gram is written in Objective-C and also makes use of Apple’s Cocoa framework. The whole program is developed in the Xcode integrated development environ-ment (IDE). The plugin implements a fast heuristic constrained linear least squares al-gorithm (CLLS-H) for estimating the diffusion and kurtosis tensors, and offers the user the possibility to choose which maps are to be generated for not only standard DTI quantities such as Mean Diffusion (MD), Radial Diffusion (RD), Axial Diffusion (AD) and Fractional Anisotropy (FA), but also DKI metrics, Mean Kurtosis (MK), Radial Kurtosis (RK) and Axial Kurtosis (AK).The plugin was subjected to both a qualitative and a semi-quantitative analysis which yielded convincing results. A more accurate validation pro-cess is still being developed, after which, and with some few minor adjust-ments the plugin shall become a valid option for DKI computation