15 resultados para Contingent claim

em Repositório Científico do Instituto Politécnico de Lisboa - Portugal


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A família de especificações WS-* define um modelo de segurança para web services, baseado nos conceitos de claim, security token e Security Token Service (STS). Neste modelo, a informação de segurança dos originadores de mensagens (identidade, privilégios, etc.) é representada através de conjuntos de claims, contidos dentro de security tokens. A emissão e obtenção destes security tokens, por parte dos originadores de mensagens, são realizadas através de protocolos legados ou através de serviços especiais, designados de Security Token Services, usando as operações e os protocolos definidos na especificação WS-Trust. O conceito de Security Token Service não é usado apenas no contexto dos web services. Propostas como o modelo dos Information Cards, aplicável no contexto de aplicações web, também utilizam este conceito. Os Security Token Services desempenham vários papéis, dependendo da informação presente no token emitido. São exemplos o papel de Identity Provider, quando os tokens emitidos contêm informação de identidade, ou o papel de Policy Decision Point, quando os tokens emitidos definem autorizações. Este documento descreve o projecto duma biblioteca software para a realização de Security Token Services, tal como definidos na norma WS-Trust, destinada à plataforma .NET 3.5. Propõem-se uma arquitectura flexível e extensível, de forma a suportar novas versões das normas e as diversas variantes que os Security Token Services possuem, nomeadamente: o tipo dos security token emitidos e das claims neles contidas, a inferência das claims e os métodos de autenticação das entidades requerentes. Apresentam-se aspectos de implementação desta arquitectura, nomeadamente a integração com a plataforma WCF, a sua extensibilidade e o suporte a modelos e sistemas externos à norma. Finalmente, descrevem-se as plataformas de teste implementadas para a validação da biblioteca realizada e os módulos de extensão da biblioteca para: suporte do modelo associado aos Information Cards, do modelo OpenID e para a integração com o Authorization Manager.

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A actual dependência mundial dos combustíveis fósseis e a crescente necessidade de redução do seu consumo têm culminado em novas directrizes de gestão de recursos de energia. A utilização de recursos energéticos renováveis apresenta-se como um caminho vital para o desenvolvimento sustentável da nossa sociedade. Assim sendo, a energia das ondas surge como potencial fonte de energia que muitos autores afirmam como sendo um dos sectores com maior potencial energético por metro quadrado de área. Contudo, esta ainda é uma tecnologia muito recente, que ainda evidencia uma grande diversidade de conceitos e que ainda se encontra numa fase inicial de demonstração. É neste contexto que foi criado o projecto CORES que visa desenvolver uma turbina de impulso com pás guia de posição variável, no âmbito do desenvolvimento de novos dispositivos e componentes para produção de energia através das ondas do mar. Neste trabalho será desenvolvido um sistema de accionamento de pás móveis para a turbina de impulso, tendo como principal objectivo o fabrico de um protótipo. Assim sendo, será realizado o desenvolvimento, dimensionamento e análise dos seus elementos móveis, bem como do sistema de actuação que melhor se adeqúe e permita um correcto funcionamento do conjunto.

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The aim of this study was the assessment of exposure to ultrafine in the urban environment of Lisbon, Portugal, due to automobile traffic, and consisted of the determination of deposited alveolar surface area in an avenue leading to the town center during late spring. This study revealed differentiated patterns for weekdays and weekends, which could be related with the fluxes of automobile traffic. During a typical week, ultrafine particles alveolar deposited surface area varied between 35.0 and 89.2 μm2/cm3, which is comparable with levels reported for other towns such in Germany and the United States. These measurements were also complemented by measuring the electrical mobility diameter (varying from 18.3 to 128.3 nm) and number of particles that showed higher values than those previously reported for Madrid and Brisbane. Also, electron microscopy showed that the collected particles were composed of carbonaceous agglomerates, typical of particles emitted by the exhaustion of diesel vehicles. Implications: The approach of this study considers the measurement of surface deposited alveolar area of particles in the outdoor urban environment of Lisbon, Portugal. This type of measurements has not been done so far. Only particulate matter with aerodynamic diameters <2.5 (PM2.5) and >10 (PM10) μm have been measured in outdoor environments and the levels found cannot be found responsible for all the observed health effects. Therefore, the exposure to nano- and ultrafine particles has not been assessed systematically, and several authors consider this as a real knowledge gap and claim for data such as these that will allow for deriving better and more comprehensive epidemiologic studies. Nanoparticle surface area monitor (NSAM) equipments are recent ones and their use has been limited to indoor atmospheres. However, as this study shows, NSAM is a very powerful tool for outdoor environments also. As most lung diseases are, in fact, related to deposition of the alveolar region of the lung, the metric used in this study is the ideal one.

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A dissertação de mestrado subordinada ao tema das Relações Intergeracionais e as Sociedades Envelhecidas surgiu, no âmbito do Mestrado em Educação Social e Intervenção Comunitária, da Escola Superior de Educação de Lisboa e teve como ponto de partida saber se a participação em actividades intergeracionais promove o envelhecimento ativo de 8 mulheres com 65 e mais anos, residentes num território multigeracional de Lisboa Oriental. A abordagem concetual do envelhecimento social, do envelhecimento ativo, das relações intergeracionais e da participação conduziu o estudo, através da triangulação dos instrumentos de análise qualitativa de entrevistas de histórias de vida e de focus group. As mulheres entrevistadas têm entre 65 e 85 anos de idade cronológica, mas em média dizem sentir que têm menos 34 anos. Afirmam, ser jovens de espirito e por isso preferem ser chamadas de seniores. Manifestam que sempre foram e são, mulheres autónomas, livres, independentes, com poder de decisão, com auto-estima elevada e com qualidade de vida. Mulheres que ocupam o tempo em actividades da vida diária, em actividades de tempos livres, e voluntariado. Mulheres reivindicativas, proativas, frontais e determinadas que assumem um papel social ativo envolvendo-se socialmente em todas as actividades produtivas ou orientadas para a performance e em actividades colectivas e ou orientadas para a união, com vista alcançar objetivos comuns. Mulheres, que ganham prestígio e estatuto na comunidade por se envolverem socialmente no processo de tomadas de decisão, organização, execução e avaliação, com as gerações mais novas. São visionárias ancestrais de espirito jovem que abrem novas portas para a construção social da velhice nas sociedades neoliberais e desafiam os humanistas quando afirmam que as atividades produtivas na velhice dão sentido à própria existência. São histórias de mulheres que nos fazem acreditar que a participação social contribui espontaneamente para o diálogo entre as gerações, em todas as fases da vida. - Abstract A dissertation on the subject of Intergenerational Relationships and Societies Aged emerged within the Master of Education Social and Community Intervention, School of Education and Lisbon had as starting point whether participation promotes intergenerational activities on aging 8 active women aged 65 years and older, residing in the territory of Eastern Lisbon multigenerational. The conceptual approach of social aging, active aging, intergenerational relations and participation conducted the study through triangulation of instruments qualitative analysis of interviews and life stories focus group. The women interviewed are between 65 and 85 years of chronological age, but on average say they feel they are under 34 years old. They claim to be young in spirit and so they prefer to be called seniors. Demonstrate that have always been and are women autonomous, free, independent, decision-making, self-esteem and quality of life. Women who occupy the time in activities of daily life, in leisure activities, and volunteering. Women reivindicativas, proactive, front and determined to play an active social role by engaging in socially productive activities or any performance-oriented and collective activities and or targeted at the union in order to achieve common objectives. Women who gain prestige and status in the community by becoming involved socially in the process of decision making, organization, implementation and evaluation with the younger generations. They are young visionary spirit of ancestors that open new doors to the social construction of old age in neoliberal societies and challenge humanists say when productive activities in old age give meaning to their own existence. These are stories of women who have us believe that social participation contributes to spontaneous dialogue between generations, in all stages of life.

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Fungal contamination in composting facilities has been associated with increased respiratory and skin pathologies among compost workers. In this study we aim to characterize the fungal contamination caused by Aspergillus genera within a totally indoor composting plant located in Portugal. Air samples of 50L were collected from 6 sampling sites through an impaction method. Surfaces samples were collected by swabbing the surfaces of the same indoor sites. Pre-treatment and waste screw were the sampling sites of the analyzed composting plant with the highest Aspergillus load in the air. Globally, the genus Aspergillus presented the highest prevalence both in the air from (90.6%), and surfaces from the same sampling sites (60.8%). The results obtained in this study claim the attention to the need of further research regarding the fungal contamination dur to Aspergillus genus in composting plants.

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The handling of waste can be responsible for occupational exposure to particles and fungi. The aim of this study was to characterize exposure to particles and fungi in a composting plant. Measurements of particulate matter were performed using portable direct-reading equipment. Air samples of 50L were collected through an impaction method with a flow rate of 140L/min onto malt extract agar supplemented with chloramphenicol (0.05%). Surfaces samples were also collected. All the samples were incubated at 27ºC for 5 to 7 days. Particulate matter data showed higher contamination for PM, and PM10 sizes. Aspergillus genus presents the highest air prevalence (90.6%). Aspergillus niger (32.6%), A. fumigatus (26.5%) and A. flavus (16.3%) were the most prevalent fungi in air sampling, and Mucor sp. (39.2%), Aspergillus niger (30.9%) and A. fumigatus (28.7%) were the most found in surfaces. the results obtained claim the attention to the need of further research.

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Dissertação apresentada à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Educação Artística, na especialização de Teatro na Educação

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Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Gestão Estratégica das Relações Públicas.

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Dissertação apresentada à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Gestão Estratégica das Relações Públicas.

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The most common scenario in occupational settings is the co-exposure to several risk factors. This aspect has to be considered in the risk assessment process because can alter the toxicity and the health effects when dealing with a co-exposure to two or more chemical agents. A study was developed aiming to elucidate if there is occupational co-exposure to aflatoxin B1 (AFB1) and ochratoxin (OTA) in Portuguese swine production. To assess occupational exposure to both mycotoxins, a biomarker of internal dose was used. The same blood samples from workers of seven swine farms and controls were consider to measure AFB1 and OTA. Twenty one workers (75%) showed detectable levels of AFB1 with values ranging from <1 ng/ml to 8.94 ng/ml and with significantly higher concentration when compared with controls. In the case of OTA, there wasn't found a statistical difference between workers and controls and the values for workers group ranged from 0.34 ng/ml to 3.12 ng/ml and 1.76 ng/ml to 3.42 ng/ml for control group. The results suggest that occupational exposure to AFB1 occurs. However, in the case of OTA results, seems that food consumption plays an important role in both groups exposure. The results claim attention for the possible implications on health of this co-exposure.

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The emergence of smartphones with Wireless LAN (WiFi) network interfaces brought new challenges to application developers. The expected increase of users connectivity will impact their expectations for example on the performance of background applications. Unfortunately, the number and breadth of the studies on the new patterns of user mobility and connectivity that result from the emergence of smartphones is still insufficient to support this claim. This paper contributes with preliminary results on a large scale study of the usage pattern of about 49000 devices and 31000 users who accessed at least one access point of the eduroam WiFi network on the campuses of the Lisbon Polytechnic Institute. Results confirm that the increasing number of smartphones resulted in significant changes to the pattern of use, with impact on the amount of traffic and users connection time.

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The aim of this study was the assessment of exposure to ultrafine in the urban environment of Lisbon, Portugal, due to automobile traffic, and consisted of the determination of deposited alveolar surface area in an avenue leading to the town center during late spring. This study revealed differentiated patterns for weekdays and weekends, which could be related with the fluxes of automobile traffic. During a typical week, ultrafine particles alveolar deposited surface area varied between 35.0 and 89.2 mu m(2)/cm(3), which is comparable with levels reported for other towns such in Germany and the United States. These measurements were also complemented by measuring the electrical mobility diameter (varying from 18.3 to 128.3 nm) and number of particles that showed higher values than those previously reported for Madrid and Brisbane. Also, electron microscopy showed that the collected particles were composed of carbonaceous agglomerates, typical of particles emitted by the exhaustion of diesel vehicles. Implications: The approach of this study considers the measurement of surface deposited alveolar area of particles in the outdoor urban environment of Lisbon, Portugal. This type of measurements has not been done so far. Only particulate matter with aerodynamic diameters <2.5 (PM2.5) and >10 (PM10) mu m have been measured in outdoor environments and the levels found cannot be found responsible for all the observed health effects. Therefore, the exposure to nano- and ultrafine particles has not been assessed systematically, and several authors consider this as a real knowledge gap and claim for data such as these that will allow for deriving better and more comprehensive epidemiologic studies. Nanoparticle surface area monitor (NSAM) equipments are recent ones and their use has been limited to indoor atmospheres. However, as this study shows, NSAM is a very powerful tool for outdoor environments also. As most lung diseases are, in fact, related to deposition of the alveolar region of the lung, the metric used in this study is the ideal one.

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Trabalho de Projecto submetido à Escola Superior de Teatro e Cinema para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Teatro – Especialização em Encenação.

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The concepts and instruments required for the teaching and learning of geometric optics are introduced in the didactic processwithout a proper didactic transposition. This claim is secured by the ample evidence of both wide- and deep-rooted alternative concepts on the topic. Didactic transposition is a theory that comes from a reflection on the teaching and learning process in mathematics but has been used in other disciplinary fields. It will be used in this work in order to clear up the main obstacles in the teachinglearning process of geometric optics. We proceed to argue that since Newton’s approach to optics, in his Book I of Opticks, is independent of the corpuscular or undulatory nature of light, it is the most suitable for a constructivist learning environment. However, Newton’s theory must be subject to a proper didactic transposition to help overcome the referred alternative concepts. Then is described our didactic transposition in order to create knowledge to be taught using a dialogical process between students’ previous knowledge, history of optics and the desired outcomes on geometrical optics in an elementary pre-service teacher training course. Finally, we use the scheme-facet structure of knowledge both to analyse and discuss our results as well as to illuminate shortcomings that must be addressed in our next stage of the inquiry.