Comunicações marítimas wi-fi usando a banda 5.8 ghz

Tendo em conta a popularidade que as comunicações Wi-Fi têm na atualidade em vários dispositivos como computadores portáteis, telemóveis ou tablets, sendo estes utilizados praticamente por qualquer pessoa, surgiu a ideia de utilizar esta tecnologia de baixo custo e isenta de licenciamento num cenário de comunicações marítimas. Neste contexto, esta permite fornecer o acesso à Internet em banda larga a grupos de embarcações, que atualmente recorrem a tecnologias de elevado custo (satélite) e/ou de banda estreita (rádios VHF). Com o acesso em banda larga, os proprietários poderão utilizar aplicações informáticas de interesse à atividade de negócio ou de lazer, até então só disponíveis junto à costa onde existe cobertura celular. Nesta tese pretende-se fazer um estudo teórico e prático sobre o alcance e respetivo desempenho de comunicações de banda larga em ambiente marítimo, utilizando parte da gama de frequências dos 5,8 GHz, isenta de licença, e a norma IEEE 802.11n. Para se utilizar equipamento produzido em massa a operar nessa gama, existem duas normas disponíveis, a IEEE 802.11a e a IEEE 802.11n. Optou-se pelo IEEE 802.11n pois os esquemas de codificação ao nível físico permitem débitos mais elevados e MIMO. Para a realização dos testes experimentais, foi necessário elaborar um protótipo de comunicação ponto a ponto, constituído por dois nós de comunicação. Um deles foi instalado numa embarcação de pesca em colaboração com a Associação Propeixe e o outro no Edifício Transparente, no Porto, em colaboração com a entidade gestora do edifício e a Associação Porto Digital. Tanto quanto se conhece é o primeiro teste de comunicações Wi-Fi realizado nestas condições a nível mundial. Os objetivos do trabalho foram atingidos. Foi possível estabelecer comunicações Wi-Fi na banda dos 5,8 GHz até cerca de 7 km com débito médio mínimo de 1 Mbit/s. O ambiente de testes desenvolvido e os resultados obtidos servirão de base para futuros trabalhos de investigação na área das comunicações marítimas.

Scientific authorships and collaboration network analysis on Chagas disease: papers indexed in PubMed (1940-2009)

Chagas disease is a chronic, tropical, parasitic disease, endemic throughout Latin America. The large-scale migration of populations has increased the geographic distribution of the disease and cases have been observed in many other countries around the world. To strengthen the critical mass of knowledge generated in different countries, it is essential to promote cooperative and translational research initiatives. We analyzed authorship of scientific documents on Chagas disease indexed in the Medline database from 1940 to 2009. Bibliometrics was used to analyze the evolution of collaboration patterns. A Social Network Analysis was carried out to identify the main research groups in the area by applying clustering methods. We then analyzed 13,989 papers produced by 21,350 authors. Collaboration among authors dramatically increased over the study period, reaching an average of 6.2 authors per paper in the last five-year period. Applying a threshold of collaboration of five or more papers signed in co-authorship, we identified 148 consolidated research groups made up of 1,750 authors. The Chagas disease network identified constitutes a "small world," characterized by a high degree of clustering and a notably high number of Brazilian researchers.

Public private collaboration: Potentials for spatial data infrastructure development in developing countries - A caste study of Nigeria

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

SOUTH AMERICAN COLLABORATION IN SCIENTIFIC PUBLICATIONS ON LEISHMANIASIS: BIBLIOMETRIC ANALYSIS IN SCOPUS (2000-2011)

Objectives: Evaluate the production and the research collaborative network on Leishmaniasis in South America. Methods: A bibliometric research was carried out using SCOPUS database. The analysis unit was original research articles published from 2000 to 2011, that dealt with leishmaniasis and that included at least one South American author. The following items were obtained for each article: journal name, language, year of publication, number of authors, institutions, countries, and others variables. Results: 3,174 articles were published, 2,272 of them were original articles. 1,160 different institutional signatures, 58 different countries and 398 scientific journals were identified. Brazil was the country with more articles (60.7%) and Oswaldo Cruz Foundation (FIOCRUZ) had 18% of Brazilian production, which is the South American nucleus of the major scientific network in Leishmaniasis. Conclusions: South American scientific production on Leishmaniasis published in journals indexed in SCOPUS is focused on Brazilian research activity. It is necessary to strengthen the collaboration networks. The first step is to identify the institutions with higher production, in order to perform collaborative research according to the priorities of each country.

HUMAN T-LYMPHOTROPIC VIRUS 1 (HTLV-1) AND HUMAN T-LYMPHOTROPIC VIRUS 2 (HTLV-2): GEOGRAPHICAL RESEARCH TRENDS AND COLLABORATION NETWORKS (1989-2012)

Publications are often used as a measure of research work success. Human T-lymphotropic virus (HTLV) type 1 and 2 are human retroviruses, which were discovered in the early 1980s, and it is estimated that 15-20 million people are infected worldwide. This article describes a bibliometric review and a coauthorship network analysis of literature on HTLV indexed in PubMed in a 24-year period. A total of 7,564 documents were retrieved, showing a decrease in the number of documents from 1996 to 2007. HTLV manuscripts were published in 1,074 journals. Japan and USA were the countries with the highest contribution in this field (61%) followed by France (8%). Production ranking changed when the number of publications was normalized by population (Dominican Republic and Japan), by gross domestic product (Guinea-Bissau and Gambia), and by gross national income per capita (Brazil and Japan). The present study has shed light on some of the defining features of scientific collaboration performed by HTLV research community, such as the existence of core researchers responsible for articulating the development of research in the area, facilitating wider collaborative relationships and the integration of new authors in the research groups.

The effect of demand information sharing in a supply chain under demand uncertainty: a simulation study

Dissertação para obtenção do Grau de Mestre em Engenharia e Gestão Industrial

Merger between Zon Multimedia and Sonaecom: Revisiting the consolidation scenario

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

The epidemiological scenario of feline sporotrichosis in Rio de Janeiro, State of Rio de Janeiro, Brazil

Introduction Sporotrichosis is a mycosis affecting both humans and animals. Within the context of the ongoing sporotrichosis epidemic in the State of Rio de Janeiro, Brazil, sick cats plays an important role in the zoonotic transmission. The aim of this study was to update the number of feline cases diagnosed at the Fundação Oswaldo Cruz (2005-2011). Methods The medical records of the cats followed were reviewed; the inclusion criterion was the isolation of Sporothrix spp. in culture. Results In total, 2,301 feline cases were identified. Conclusions These results should alert sanitary authorities to the difficulties associated with sporotrichosis control.

Role of Intersectoral Collaboration in Mental Health Policy Formulation And Service Delivery in Saint Lucia

RESUMO: Santa Lúcia pequena ilha de país em desenvolvimento com recursos limitados e é confrontada com uma série de desafios socioeconômicos que exigem soluções criativas e inovadoras. É comprovado que a combinação de recursos entre setores para estabelecer os determinantes social, econômico e ambiental da saúde são uma estratégia útil para melhorar a saúde da população, principalmente a sua saúde mental. Este estudo, o primeiro do seu tipo em Santa Lúcia, procurou examinar até que ponto a disponibilidade de uma política nacional de saúde mental levou a ação intersetorial para o fornecimento de serviços e promoção da saúde mental. Além disso, o estudo examinou o nível de colaboração intersetorial que existe entre as agências que prestam cuidados diretos e serviços de suporte para pessoas com doenças mentais e problemas sérios de saúde mental. O estudo também teve como objetivo identificar os fatores que promovem ou dificultam a colaboração intersectorial e gerar recomendações que possam ser aplicadas para países muito pequenos e com perfis socioeconômicos semelhantes. Os dados gerados a partir de três (3) fontes foram sintetizados para formar uma visão ampla das questões. Uma avaliação da política de saúde mental de 2007, uma avaliação que identifica até que ponto a ação intersetorial atualmente deixa a prestação de serviços de saúde mental e a administração de entrevistas semiestruturadas nas mãos de gestores do programa de diferentes agências em todos os setores. O estudo concluiu que, apesar da disponibilidade de uma política de saúde mental, que articula clara e explicitamente a colaboração intersetorial como área prioritária para ação, quase não existe no sistema de fornecimento atual do serviço. Os provedores de serviços em todos os setores reconhecem que há os benefícios da colaboração intersectorial e com entraves significativos em relação à colaboração intersetorial, que por sua vez, impede uma abordagem nacional para o planejamento e o fornecimento do serviço. A colaboração intersetorial não será possível se os próprios setores dependerem da abordagem direta do setor da saúde ou se a atmosfera geral for ofuscada pela estigmatização das doenças mentais.------------------------------------------------------------------------ABSTRACT: Saint Lucia a small island developing country with limited resources, is faced with a number of socio-economic challenges which require creative and innovative solutions to address. Combining resources across sectors to address the social, economic and environmental determinants of health has proven to be a useful strategy for improving population health in particular mental health. This study, the first of its kind for Saint Lucia sought to examine the extent to which the availability of a national mental health policy led to intersectoral action for mental health promotion and service delivery. In addition the study examined the level of intersectoral collaboration which actually exist between agencies which provide direct care and support services to people with mental illnesses and significant mental health problems. The study also aimed to identify the factors which promote or hinder intersectoral collaboration and generate recommendations which can be applied to extremely small countries with similar socio-economic profiles. Data generated from three (3) sources was synthesized to form a broad picture of the issues. An evaluation of the mental health policy of 2007, an assessment of the extent to which intersectoral action currently exist in mental health service delivery and the administration of semi-structured interviews with program managers from different agencies across sectors to identify implementation issues. The study concluded that despite the availability of a mental health policy which clearly and explicitly articulates intersectoral collaboration as a priority area for action, very little exists in the current service delivery system. Services providers across sectors acknowledge the benefits of intersectoral collaboration and that there are significant barriers to intersectoral collaboration, which in turn hinders a national approach to service planning and delivery. Intersectoral collaboration is not possible if sectors themselves are dependent on a top-down health sector driven and dominated approach, or if the general atmosphere is clouded by stigmatization of mental health illnesses.

Search for Scalar-Charm Pair Production in pp Collisions at s√=8 TeV with the ATLAS Detector

The results of a dedicated search for pair production of scalar partners of charm quarks are reported. The search is based on an integrated luminosity of 20.3fb−1 of pp collisions at s√=8 TeV recorded with the ATLAS detector at the LHC. The search is performed using events with large missing transverse momentum and at least two jets, where the two leading jets are each tagged as originating from c-quarks. Events containing isolated electrons or muons are vetoed. In an R-parity-conserving minimal supersymmetric scenario in which a single scalar-charm state is kinematically accessible, and where it decays exclusively into a charm quark and a neutralino, 95% confidence-level upper limits are obtained in the scalar-charm—neutralino mass plane such that, for neutralino masses below 200 GeV, scalar-charm masses up to 490 GeV are excluded.

Search for New Phenomena in Dijet Angular Distributions in Proton-Proton Collisions at s√=8 TeV Measured with the ATLAS Detector

A search for new phenomena in LHC proton-proton collisions at a center-of-mass energy of s√=8 TeV was performed with the ATLAS detector using an integrated luminosity of 17.3 fb−1. The angular distributions are studied in events with at least two jets; the highest dijet mass observed is 5.5 TeV. All angular distributions are consistent with the predictions of the Standard Model. In a benchmark model of quark contact interactions, a compositeness scale below 8.1 TeV in a destructive interference scenario and 12.0 TeV in a constructive interference scenario is excluded at 95% CL; median expected limits are 8.9 TeV for the destructive interference scenario and 14.1 TeV for the constructive interference scenario.

Search for type-III Seesaw heavy leptons in pp collisions at s√=8 TeV with the ATLAS Detector

A search for the pair-production of heavy leptons (N0,L±) predicted by the type-III seesaw theory formulated to explain the origin of small neutrino masses is presented. The decay channels N0→W±l∓ (ℓ=e,μ,τ) and L±→W±ν (ν=νe,νμ,ντ) are considered. The analysis is performed using the final state that contains two leptons (electrons or muons), two jets from a hadronically decaying W boson, and large missing transverse momentum. The data used in the measurement correspond to an integrated luminosity of 20.3fb−1 of pp collisions at s√=8 TeV collected by the ATLAS detector at the LHC. No evidence of heavy lepton pair-production is observed. Heavy leptons with masses below 325--540 GeV are excluded at the 95% confidence level, depending on the theoretical scenario considered.