Estudo de novas aplicações da fibra de carbono nos materiais de construção

Dissertação de Mestrado em Engenharia Civil - Área de Especialização Materiais de ConstruçãoO crescente desenvolvimento e aplicação de novos materiais nas últimas décadas permitiram melhorar a qualidade de vida para o ser humano e consequentemente a sociedade em que está inserido. As fibras de carbono têm merecido uma atenção especial devido às suas características particulares, as quais se destacam a sua baixa densidade associada a uma elevada resistência mecânica assim com as suas propriedades eléctricas. Este trabalho apresenta um estudo sobre as propriedades eléctricas e piezoelectricas das fibras de carbono. Estudou-se a aplicação de uma nova base de suporte, o silicone, para o fabrico de um compósito com incorporação de fibras de carbono com vista a avaliar as suas propriedades piezoresistivas para funcionar como sensor. De modo a se poder avaliar adequadamente a capacidade sensitiva de cada um dos sensores, realizaram-se ensaios cíclicos e estáticos de deformação. O primeiro, visou o estudo da reversibilidade dos valores lidos assim como a extracção das curvas de calibração que permitam efectuar uma relação com a deformação que se encontra aplicada no sensor. Já o ensaio em condições estáticas permitiu avaliar a evolução das leituras em condições de deformação constante e assim verificar a sua estabilidade ao longo do tempo. O estudo ficou concluído com a avaliação da sua aplicabilidade prática em que se sujeitou os sensores às condições reais de obra, onde foram colocados nos solos das fundações das estruturas a construir, devidamente escolhidas para o efeito. Estudou-se igualmente as propriedades termoeléctricas das fibras de carbono quando incorporadas num material base de suporte com a finalidade de este poder actuar como um elemento capaz de produzir radiação térmica quando sujeito a uma corrente eléctrica. Foram desenvolvidas placas com incorporação de fibras de carbono em diferentes quantidades, que simularam um pavimento radiante. Estas placas serviram para quantificar o consumo energético e determinar poder calorífico radiante máximo. Por ultimo, foi realizada uma comparação quantitativa das placas desenvolvidas neste trabalho com as placas comercialmente disponíveis no mercado.The rapid development of new materials in the last few decades has allowed a significant improvement of the quality of life. Special attention has been given to carbon fibbers due to its unique properties; which combines the low density with high mechanical properties and interesting electrical properties. In this research work, a study was carried out to assess the electrical and piezoelectric properties of the carbon fibbers. A new composite, using a silicone rubber as binder, reinforced with carbon fibbers was developed that can act as a sensor. In order to properly evaluate the sensor sensitivity, a set of experimental tests was carried out in the laboratory. The sensors were submitted to compressive cyclic loading and to a prolonged constant deformation test. The first one aimed at studying the reversibility of the measurements under cycling loading in order to estimate the calibration curves, and establish a relationship between electrical resistance and the applied deformation. The constant deformation test allowed the evaluation of electrical resistance readings when submitted to constant deformation for a long period of time. Polymers are known to be sensitive to creep and as such this test was important for evaluating the practical application of the sensor. Furthermore, the sensors were applied in the real environment conditions on a construction site and their performance was monitored. Sensors were placed under the foundation and hence registered the real movements of the soil. Also in this research work, the thermoelectric properties of carbon string were studied when placed within gypsum and polymeric boards, so that the resulting composite could act as an element capable of thermal radiation, when plugged into an electric current. Boards were developed with deferent amounts of carbon strings simulating thermal radiation pavement and electrical consumptions were estimated. The results obtained indicate that it is possible to manufacture sensors using carbon fibre reinforced polymers for general application in construction industry. Furthermore, the gypsum and polymer reinforced with carbon strings can be used for thermal radiation pavements with lower energy consumption

BARRACA: a shelter for cultural heritage in Algarve: business plan

This project addresses the need to protect the cultural heritage in places with less global influence and how to generate revenue from it, exploring the current trends on cultural and creative tourism. To do so it is used the example of Algarve, a destination often linked with sun and beach tourism, despite havinbg plenty and various other resources capable of providing its visitors a complete and memorable experience. BARRACA is a project that proposes a simple and laidback space where the local youth and visitors can interact and be exposed to Algarve’s cultural heritage while fulfilling the standards demanded these days for an establishment directed at this target audience. For that to happen, the idea is to organize exhibitions and events using the region's landscape, traditional economic activities, gastronomy, as well as products and works from local artists, craftsmen and producers, and many other activities always using the local cultural heritage as background. This document presents the entire business plan necessary to put this project into practice, from the theoretical base behind the whole concept to the financial analysis on it.Este projeto explora a importância de proteger a herança cultural local em destinos de menor expressão a nível global e como lucrar com esta necessidade, explorando as atuais tendências no turismo criativo e cultural. Para tal, é usado o exemplo do Algarve, destino muitas vezes associado ao turismo de sol e praia, mas que possui muitos outros e variados recursos capazes de proporcionar aos visitantes uma experiência completa e memorável. A BARRACA propõe um espaço, simples e descontraído, onde os jovens locais e visitantes possam interagir e estar expostos à herança cultural local enquanto vêm cumpridos os padrões que hoje em dia se pedem a um estabelecimento direccionado a este público. Para que tal aconteça, serão organizadas exposições e eventos usando a paisagem, as atividades económicas tradicionais da região, gastronomia e produtos, obras e trabalhos de artistas, artesãos e produtores locais e muitas outras atividades usando diversos elementos da cultura Algarvia como pano de fundo. Neste documento é então apresentado todo o plano de negócios necessário para que este projeto possa ser posto em prática, começando pela base teórica e conceito e terminando na análise financeira do mesmo

Potential market value for portuguese territory : demographics as mobility proxy

Mestrado Bolonha em Econometria Aplicada e PrevisãoIn retail a business location is of extreme importance as it can directly affect profits. Therefore, it is of the utmost importance to be accurate and critical when allocating products and sales personal to a location. This report is the result of the work performed at PSE1 during a curricular internship. PSE is a data science company that offers data science services and market research. They are currently developing a model that segments a region according to its Potential Market Value. This model relies on multiple factors, including human mobility data. The challenge lies in implementing the model to new locations for which they do not yet have accurate human mobility data. This was the focus of the work developed, finding a proxy for human mobility by using demographic data pared with information regarding different types of Points of Interest. To tackle the issue at hand data mining techniques were used following the CRISP-DM methodology as well as the Tabu Search Algorithm, culminating in the creation of a Potential Market Segmentation Model that can be reproduced for multiple locations and even other companies and retail industries. The results of the new model exceeded the expectations, and this new approach seems to be quite promising. Although there is a loss of information regarding mobility, there is an increase in the knowledge regarding the consumer profile. It is important to notice that the success of the model is related to the type of product, since the consumption of the product used in this study is highly correlated with the residency area of the consumer which means that loosing information about mobility does not pose a major setback.info:eu-repo/semantics/publishedVersio

FMKe: A realistic benchmark for key-value stores

Standard benchmarks are essential tools to evaluate and compare database management systems in terms of relevant semantic properties and performance. They provide the means to evaluate a system with workloads that mimic real applications. Although a number of realistic benchmarks already exist for relational database systems, the same cannot be said for NoSQL databases. This latter class of data storage systems has become increasingly relevant for geo-distributed systems, and this has led developers and researchers to either rely on benchmarks that do not model realistic workloads or to adapt the aforementioned benchmarks for relational databases to work for NoSQL databases, in a somewhat ad-hoc fashion. Since these benchmarks assume an isolation and transactional model in the database, they are inherently inadequate to evaluate NoSQL databases. In this thesis, we propose a new benchmark that addresses the lack of realistic evaluation tools for distributed key-value stores. We consider a workload that is based on information we have acquired about a real world deployment of a large-scale application that operates over a distributed key-value store, that is responsible for managing patient prescriptions at a nation-wide level in Denmark. We design our benchmark to be extensible to a wide range of distributed key-value storage systems and some relational database systems with minimal effort for programmers, which only need to design and implement specific data storage drivers to benchmark different alternatives. We further present a study on the performance of multiple database management systems in different deployment scenarios

A aplicação do GOHAI, numa população idosa de dois centros de saúde da unidade setentrional de Lisboa

Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas MonizObjectivos: Identificar a percepção que os idosos têm sobre a sua saúde oral, nos dois centros de saúde, caracterizar sócio demograficamente a população idosa frequentadora do Centro de Saúde de Sete Rios e a população idosa frequentadora do Centro de Saúde de Loures, identificar os principais factores sociodemográficos associados à variável, autopercepção, nos dois locais e compará-los. Materiais e métodos: amostra constituída por 64 idosos utentes do Centro de Saúde de Sete Rios e 51 idosos utentes do Centro de Saúde de Loures com idade igual ou superior a 65 anos. As condições subjectivas relacionadas com as características individuais de cada idoso foram analisadas através de um questionário específico e a auto-avaliação da qualidade de vida relacionada com a saúde oral foi medida através de perguntas de carácter geral para o idoso. Foi utilizado o Geriatric Oral Health Assessment Index (GOHAI) com o objectivo de avaliar a autopercepção de cada idoso. Os resultados foram tratados estatisticamente pelo software SPSS. Usaram-se medidas de frequência (absoluta e relativa) e outras de estatística descritiva (mediana, desvio padrão, valor máximo, valor mínimo). Com o intuito de correlacionar as variáveis utilizaram-se os testes de qui-quadrado, Spearman e o teste t-independente, usando como referência para aceitar ou rejeitar a hipótese nula um nível de significância p ≤ 0,05. Resultados: A média de idades da população idosa frequentadora do Centro de Saúde de Sete Rios foi de 75,84 anos e no Centro de saúde de Loures foi de 72,69 anos. O índice GOHAI apresenta diferenças estatisticamente significativas entre os dois Centros de Saúde (p=0,025). A dificuldade na mastigação interfere de forma acentuada na qualidade de vida, ao nível do desconforto e no recurso a medicação, em Sete Rios (p<0,001). A dor na cavidade oral interfere na qualidade de vida da saúde oral, ao nível social, tanto em Sete Rios (p<0,001) como em Loures (p=0,015). Conclusão: o índice de GOHAI foi identificado como moderado em Sete Rios e em Loures

The internationalization process of born global firms in high-tech and low-tech industries: Is there any difference?

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 EconomicsThe impact of industry characteristics on born global firms’ internationalization process is widely acknowledged. Even though there are studies focusing on both high-tech and low-tech industries, the differences between their internationalization patterns have not been generally analyzed. Through a multiple case-study research focusing on a comparison between both industries, we are able to identify differences in the internationalization pattern and specific influential factors. Our findings show that (1) high-tech firms are more international than low-tech ones; (2) the global nature of high-tech firms triggers internationalization while low-tech firms are driven by home market conditions and entrepreneurial traits; (3) networks have a distinct role between industries; (4) the concept of psychic distance may still be applied to this type of firms

Carlsberg - financial analysis and equity valuation

This report is part of the valuation of Carlsberg A shares –CARLA DC on Bloomberg and CARLa.CO on Reuters. Throughout this part of the main project, already with a deep understanding of Carlsberg’s positioning in the beer industry, we shifted our focus towards Carlsberg’s financial performance. With these analyses we built the foundations for our final valuation model of Carlsberg A shares. To ensure accuracy and reliability we based our study in the company’s financials, but also industry competitors, financial studies, and our own assumptions. At the end of this part, investors should understand the main financial indicators for Carlsberg, but also final valuation for Carlsberg A shares given three different scenarios

Proceratium melinum (Roger, 1860): the first record of Proceratiinae ants from Portugal (Hymenoptera, Formicidae).

ABSTRACT: The ant Proceratium melinum (Roger, 1860) is reported for the first time from Portugal. This is also the first record of Proceratiinae in this country, from which a total of 133 ant species are now known. The species was collected in a cork oak stand (montado) using pitfall traps.info:eu-repo/semantics/publishedVersio