Influence of the human head in the radiation of a mobile antenna

The big proliferation of mobile communication systems has caused an increased concern about the interaction between the human body and the antennas of mobile handsets. In order to study the problem, a multiband antenna was designed, fabricated and measured to operate over two frequency sub bands 900 and 1800 MHz. After that, we simulated the same antenna, but now, in the presence of a human head model to analyze the head's influence. First, the influence of the human head on the radiation efficiency of the antenna has been investigated as a function of the distance between the head and the antenna and with the inclination of the antenna. Furthermore, the relative amount of the electromagnetic power absorbed in the head has been obtained. In this study the electromagnetic analysis has been performed via FDTD (Finite Difference Time Domain)

The Roman Villa in Rabaçal and Álvaro Siza

The residential area of the Roman villa in Rabaçal is a rare example of a house with an octagonal peristyle remarkable by its design coherence at all architectural levels, from the overall scale to decorative motifs. Everything is regulated by proportions derived from its octagonal plan naturally based in ad quadratum geometry. Recently, Siza was challenged to design covers and a visit tour in order to preserve this invaluable patrimony. Quite aware of the quality of the architecture displayed in this Roman villa he must have recognized in-situ many of his own architectural concerns. The sketchbook was opened, and the drawing search led him to propose two wood rectangular grid covers which, in spite of their modernity and technical sophistication, are still shapes with formal affinities with each part of the villa

Web 2.0 in restaurants : insights regarding TripAdvisor’s use in Lisbon

TripAdvisor is a Web 2.0 platform that gathers information about restaurants, hotels and sightseeing spots, generated by users for users. It also has an application for mobile devices, which allows users to know what they desire at anytime, anywhere, increasing their user experience (Lugano 2008). This dissertation is focused on the use of this platform by restaurants and users. As so, theoretical concepts like Web 2.0, User-Generated Content, Mobile Social Network, Electronic Word of Mouth and Mobile Marketing are studied in order to know whether or not TripAdvisor is being used and, if positive, in what conditions. With these theories in mind, a dissertation model is created. Thus, willing to know whether or not Lisbon restaurants and users of TripAdvisor are taking advantage of this platform (i.e. answer the research question), several secondary questions arise. These are answered by the nine hypotheses generated, which are based on the model’s goals. Subsequently, in order to collect information from restaurants and users that can verify or not the hypotheses, two surveys are created. Intermediary conclusions that aim to validate each hypothesis are drawn from the results obtained. When analysing these intermediary conclusions, the results show two different answers to the research question. On one hand, restaurants are taking advantage from TripAdvisor’s platform, even if they are not using all the capacities offered. On the other hand, Lisbon users are not yet taking benefits from this platform. This inconsistency can be explained due to the fact that restaurants centre TripAdvisor around tourists and Lisbon habitants use it outside of Lisbon while travelling. Thus, Lisbon citizens do not use this platform on a daily basis: they do it while visiting other cities. In comparison, Lisbon restaurants use this platform in order to attract tourists, which mean that they are taking advantage of TripAdvisor but not from Lisbon users.O TripAdvisor é uma plataforma Web 2.0 que agrega informação sobre restaurantes, hotéis e espaços culturais, gerado por utilizadores para utilizadores. Esta plataforma possui também uma aplicação para dispositivos móveis, que permite aos utilizadores saber o que desejam em qualquer momento e lugar, aumentando a sua participação (Lugano 2008). A presente dissertação foca-se no uso desta plataforma tanto por parte dos clientes como dos restaurantes. Assim, conceitos como Web 2.0, User-Generated Content, Mobile Social Network, Electronic Word of Mouth e Mobile Marketing são estudados para perceber se o TripAdvisor está a ser usado e, em caso afirmativo, sob que condições. Tendo estes conceitos presentes, é criado um modelo para a dissertação. Neste, e com o objetivo de saber se os restaurantes e os clientes na zona de Lisboa estão a tirar partido da plataforma TripAdvisor (isto é, responder à pergunta de investigação), várias questões secundárias são levantadas. Estas são respondidas pelas nove hipóteses geradas, que por sua vez são baseadas nos objetivos do modelo. Consequentemente, e de forma a recolher informação acerca dos restaurantes e clientes que permite validar ou não as hipóteses, dois questionários são criados. Com os resultados obtidos, conclusões intermédias que visam validar cada hipótese são geradas. Os resultados da análise das conclusões intermédias apresentam duas respostas diferentes para a pergunta de investigação. Por um lado, os restaurantes estão a tirar vantagens da plataforma do TripAdvisor, mesmo não usando todos os serviços oferecidos. Por outro lado, os clientes lisboetas ainda não estão a tirar partido desta plataforma. Esta inconsistência pode ser explicada devido ao facto de os restaurantes e clientes de Lisboa estarem a usar a plataforma para turistas e enquanto turistas, respectivamente. Assim, os utilizadores lisboetas não utilizam o TripAdvisor no seu quotidiano: fazem-no enquanto visitantes de outras cidades. Em comparação, os restaurantes de Lisboa usam esta plataforma para atrair turistas, o que significa que estão a tirar benefícios do TripAdvisor mas não por parte dos clientes lisboetas

Detect and Pointing Algorithms Performance for a 2D Adaptive Antenna Array

In recent decades, we have witnessed a great progress in wireless communications. The huge amount of data that users expect to access has required an effort to increase the capacity of wireless networks. The main limitation of these communication systems is the increasing interference between channels and multipath fading. Smart antennas technology has emerged, solving some of these problems and improving the performance of wireless networks. This chapter addresses a group of algorithms, directions of arrival (DOA) and beamforming, applied to planar antenna arrays. The algorithms are simulated, and their performance is evaluated in terms of runtime, accuracy and dependence with signal-to-noise ratio (SNR), applied to a smart antenna system

Understanding the role of the long non-coding RNA MIR503HG in endothelial-to-mesenchymal transition during vascular remodelling

Endothelial-to-mesenchymal transition (EndMT) is a dynamic biological process present during development and involved in a variety of pathological vascular remodelling scenarios. However, despite our growing understanding of the key cellular alterations required, the precise molecular determinants governing this phenotypical transition remain elusive. With long non-coding RNAs (lncRNA) now emerging as powerful regulators of gene expression we sought to understand their role in the process of EndMT. To replicate EndMT in vitro and characterise its molecular signature, human umbilical vein endothelial cells (HUVEC) and human pulmonary artery endothelial cells (HPAEC) were exposed to a continuous co-treatment of transforming growth factor-beta 2 (TGF-β2) and interleukin 1 beta (IL-1β) for a total of 7 days. Using high-throughput RNA-sequencing analysis of these cells, a total of 103 differential expressed lncRNAs were identified. Of these, the downregulation of the lncRNA MIR503HG was found to be a prevalent feature present in multiple human primary EC types undergoing EndMT in vitro. Further analysis revealed that depletion of MIR503HG was sufficient to elicit a robust EndMT phenotype, with a significant increase in the expression of SNAI2, ACTA2 and COL1A1, accompanied by repression of CD31. Conversely, ectopic expression of a single MIR503HG transcript suppressed these hallmark EndMT-associated changes despite TGF-β2 and IL-1β co-treatment. Accompanying RNA-sequencing of these cells showed that the overexpression of MIR503HG alone was able to inhibit over 25% of the EndMT transcriptional profile. Crucially, these changes were found to be independent of the functional regulation of miR-503 and miR-424, found within the MIR503HG locus. Our findings were then confirmed in vivo using a sugen/hypoxia-induced model of pulmonary hypertension (PH) established in endothelial lineage-tracing mice. Here, the expression of the MIR503HG mouse homolog (Gm28730) was significantly downregulated in association with an EndMT profile in the lung. Conversely, targeted up-regulation of MIR503HG in the mouse lung significantly suppressed the appearance of mesenchymal markers in CD31+ cells during PH. Notably, MIR503HG availability was also found to be decreased in lung tissue sections from patients with idiopathic pulmonary arterial hypertension (IPAH) and cultured blood outgrowth ECs isolated from patients with heritable pulmonary arterial hypertension (HPAH). Collectively, our studies identify MIR503HG as essential in maintaining EC phenotypical commitment and preventing EndMT both in vitro and during disease

Sistema de Visualização 3D e Ajuste Manual de Soluções de Paletização

O desenvolvimento económico, e a evolução dos modelos de negócio, trazem cada vez mais exigência aos processos logísticos de armazenagem e movimentação de bens entre cliente e fornecedor. Estes processos de armazenagem, manipulação e envio de bens necessita de ser realizado atempadamente e com o menor custo possível. Um dos fatores mais importantes para atingir esses objetivos é o aproveitamento eficiente do espaço que consiste no processo de paletização. Este consiste na colocação e acondicionamento dos produtos numa ou mais camadas sobre paletes, cumprindo restrições dimensionais, de equilíbrio, de peso máximo, entre outras. Este caso de estudo foca-se na conceção e manipulação de soluções de paletização. No âmbito deste trabalho foi desenhado e implementado um sistema de pré-visualização e manipulação dessas soluções (obtidas através de uma ferramenta de otimização que não foi alvo do trabalho desta tese). Este sistema apoia o utilizador na realização de eventuais ajustes manuais e preferências que se mostrem necessárias à posterior validação das soluções e à sua colocação em produção. O sistema divide-se em dois subsistemas distintos, contudo complementares, com interfaces de utilizador para web: um primeiro, referente à criação e manipulação de soluções de paletização em duas dimensões, e um segundo, que permite a pré-visualização das soluções em três dimensões. Foram estudadas e selecionadas as melhores práticas e técnicas nas áreas da Usabilidade, Design Centrado no Utilizador e Experiência do Utilizador para adaptar a solução final ao utilizador, permitindo-lhe uma experiência produtiva e agradável. Numa fase final do projeto, a solução foi avaliada qualitativa e quantitativamente através da realização de questionários com o fim de avaliar a experiência subjetiva dos utilizadores. Os resultados dessa avaliação mostraram que os objetivos foram atingidos, tendo-se respeitado na integra os requisitos definidos para o sistema.The economic development, and the evolution of business models, bring more and more exigency to the logistic processes of storage and movement of goods between client and supplier. These processes of storage, handling and shipment of goods need to be carried out in a timely manner and at the lowest cost possible. One of the most important factors in achieving these objectives is the efficient use of the space that consists of the palletising process. This involves placing and packing the products in one or more layers on pallets, complying with dimensional, balance and maximum weight restrictions, among others. This case study focuses on the design and manipulation of palletizing solutions. Within the scope of this work, a system of pre-visualisation and manipulation of these solutions was designed and implemented (the optimization tool that produces these solutions is outside the scope of this thesis). This system supports the user in making any manual adjustments and preferences that may be necessary for the subsequent validation of the solutions and their implementation into production. The system is divided into two distinct subsystems, however complementary, with user interfaces for the web: a first, referring to the creation and manipulation of palletization solutions in two dimensions, and a second, which allows the visualization of solutions in three dimensions. The best practices and techniques in the areas of Usability, User Centered Design and User Experience were studied and selected to adapt the final solution to the user, allowing a productive and pleasant experience. In a final phase of the project, the solution was assessed qualitatively and quantitatively through questionnaires in order to assess the subjective experience of the users. The results of this assessment showed that the objectives were achieved, and the requirements defined for the system were fully respected

Há assimetria no repasse dos juros bancários de variações na taxa Selic?

This paper tests and find evidence that support the view that credit interest rates respond more to increases than to decreases in the Central Bank basic interest rate (Selic). This asymmetry is robust to an event analysis, in which the availability of a dataset containing daily information is explored in order to isolate monetary policy shocks on interest rates as the cause of the assymetric response of interest rates, as a shift in the basic interest rate is akin to an increase in marginal cost and thus corresponds to a shift in the supply curve of banks. The econometric identification hypothesis is that banks (supply) react faster to monetary shocks than consumers (demand for credit). The empirical evidence of greater rigidity to Selic decreases contributes to the literature of bank behavior in credit markets and the transmission mechanism of monetary policy in Brazil.Microeconomics of Banking, interest pass-through and Adverse Selection JEL Codes: L11, G21

Um projeto de educação e intervenção social com população residente em bairros de habitação social

O projeto “Eu, o Bairro, Nós e Voz” foi desenvolvido em cinco bairros de habitação social de uma União de Freguesias da cidade do Porto e contou com a participação dos/as moradores/as e das respetivas Associações de Moradores. Este projeto teve como finalidade: melhorar a participação de todos/as os/as atores/atrizes locais para a resolução colaborativa das necessidades da comunidade, aumentando a qualidade de vida dos/as moradores/as. Para que tal fosse possível, foram definidos dois objetivos gerais: 1) possibilitar a cooperação entre todos/as os/as atores/atrizes locais de forma a melhorar a qualidade de vida da comunidade; e 2) promover o interconhecimento entre os/as moradores/as do bairro. Para alcançar os referidos objetivos foram desenvolvidas duas ações: “A comunicar é que a gente se conhece”, que procurava diversificar as estratégias de comunicação entre todos/as os/as atores/atrizes locais; e “Eu e o meu bairro, qual o nosso futuro?”, que teve o intuito de trabalhar as representações dos/as jovens moradores/as do bairro para que fosse possível valorizar-se a vida no bairro e os/as seus/suas residentes. Com o desenvolvimento destas ações é notório que a comunidade começou a dar os primeiros passos na procura por soluções coletivas, acreditando nas potencialidades do local onde residem e olhando para os/as seus/suas vizinhos/as do bloco ao lado ou do bairro ao lado como fundamentais para a construção de resoluções coletivas. De salientar que ao longo do projeto privilegiou-se a Investigação-Ação Participativa, numa perspetiva colaborativa e participativa, destacando-se o diálogo, partilha e a escuta para a coconstrução do projeto.The project “Eu, o Bairro, Nós e Voz” was developed in five social housing neighborhoods of a Union of Parishes in the city of Porto and had the participation of residents and their respective Residents Associations. This project aimed to: improve the participation of all local actors (actresses) for the collaborative resolution of community needs, increasing the quality of life of residents. To make this possible, two general objectives were defined: 1) to enable cooperation between all local actors (actresses) to improve the community's quality of life; and 2) promote inter-knowledge among the residents of the neighborhood. To achieve these objectives, two actions were developed: “Communicating means getting to know each other”, which sought to diversify communication strategies among all local actors (actresses); and “Me and my neighborhood, what is our future?”, which aimed to work on the representations of young residents of the neighborhood so that it was possible to value life in the neighborhood and its residents. With the development of these actions, it is clear that the community began to take the first steps in the search for collective solutions, believing in the potential of the place where they live and looking to their neighbors in the next block or in the adjacent neighborhood as fundamental for the construction of collective resolutions. It should be noted that throughout the project, Participatory Research Action was privileged, in a collaborative and participatory perspective, highlighting dialogue, sharing and listening for the co-construction of the project