986 resultados para software-defined radio
Resumo:
Nesta Tese foi desenvolvida uma plataforma online multiutilizador, que tem como objetivo principal comparar algoritmos de análise de imagens para de-terminar o seu grau de eficácia. Um exemplo de aplicação é a comparação de algoritmos de análise de imagens da retina para deteção de drusas. A compa-ração é feita considerando um dos algoritmos como referência padrão e sobre o este são avaliados os restantes. O funcionamento da plataforma é semelhante à de um fórum, onde é possível a um utilizador criar tópicos publicando imagens e seu descritivo. Após a cria-ção do tópico qualquer utilizador pode visualizar o mesmo, dando a hipótese de comentar ou de acrescentar imagens processadas com os seus próprios al-goritmos de análise. Com o aumento de imagens processadas, obtém-se uma base de dados de algoritmos de análise de imagens sobre a qual é possível avaliar o seu grau de eficácia. A plataforma pretende também criar comunidades onde os utilizadores pos-sam interagir uns com os outros comentando sobre os tópicos, contribuindo assim para o melhoramento dos algoritmos. Deste modo, além de uma base de dados que qualquer utilizador pode usar, obtém-se uma fonte de informação disponibilizada por outros profissionais da área.
Resumo:
RESUMO - O sistema de saúde é constantemente sujeito a pressões sendo as mais relevantes a pressão para o aumento da qualidade e a necessidade de contenção de custos. Os Eventos Adversos (EAs) ocorridos em meio hospitalar constituem um sério problema de qualidade na prestação de cuidados de saúde, com consequências clinicas, sociais, económicas e de imagem, que afectam pacientes, profissionais, organizações e o próprio sistema de saúde. Os custos associados à ocorrência de EAs em meio hospitalar, incrementam significativamente os custos hospitalares, representando cerca de um em cada sete dólares gastos no atendimento dos doentes. Só na última década surgiram estudos com o objectivo principal de avaliar esse impacto em meio hospitalar, subsistindo ainda uma grande indefinição quanto às variáveis e métodos a utilizar. O objectivo principal deste trabalho de projecto foi conhecer e caracterizar as diferentes metodologias utilizadas para avaliação dos custos económicos, nomeadamente dos custos directos, relacionados com a ocorrência de eventos adversos em meio hospitalar. Tendo em atenção as dificuldades referidas, utilizou-se como metodologia a revisão narrativa da literatura, complementada com a realização de uma técnica de grupo nominal. Os resultados obtidos foram os seguintes: i) a metodologia utilizada na maioria dos estudos para determinar a frequência, natureza e consequências dos EAs ocorridos em meio hospitalar, utiliza matrizes de base observacional, analítica, com base em estudos de coorte retrospectivo recorrendo aos critérios definidos pelo Harvard Medical Practice Study; ii) a generalidade dos estudos realizados avaliam os custos directos dos EAs em meio hospitalar, iii) verificou-se a existência de uma grande diversidade de métodos para a determinação dos custos associados aos EAs. A generalidade dos estudos determina esse valor com base na contabilização do número de dias adicionais de internamento, resultantes do EA, valorizados com base em custos médios; iv) o grupo de peritos, propôs como metodologia para a determinação do custo associado a cada EA, a utilização de sistemas de custeio por doente; v) propõe-se o desenvolvimento de uma plataforma informática, que permita o cruzamento da informação disponível no registo clinico electrónico do doente com um sistema automático de identificação de EAs, a desenvolver, e com sistemas de custeio por doente, de modo a valorizar os custos por doente e por tipo de EA. A avaliação dos custos directos associados à ocorrência de EAs em contexto hospitalar, pelo impacto económico e social que tem nos doentes e organizações, será seguramente uma das áreas de estudo e investigação futuras, no sentido de melhorar a eficiência do sistema de saúde e a qualidade e segurança dos cuidados prestados aos doentes.
Resumo:
Contém CD com áudio como anexo
Resumo:
Taking a Media Anthropology’s approach to dynamics of mediated selfrepresentation in migratory contexts, this thesis starts by mapping radio initiatives produced by, for and/or with migrants in Portugal. To further explore dynamics of support of initial settlement in the country, community-making, cultural reproduction, and transnational connectivity - found both in the mapping stage and the minority media literature (e.g. Kosnick, 2007; Rigoni & Saitta, 2012; Silverstone & Georgiou, 2005) - a case study was selected: the station awarded with the first bilingual license in Portugal. The station in question caters largely to the British population presenting themselves as “expats” and residing in the Algarve. The ethnographic strategy to research it consisted of “following the radio” (Marcus, 1995) beyond the station and into the events and establishments it announces on air, so as to relate production and consumption realms. The leading research question asks how does locally produced radio play into “expats” processes of management of cultural identity – and what are the specificities of its role? Drawing on conceptualizations of lifestyle migration (Benson & O’Reilly, 2009), production of locality (Appadurai 1996) and the public sphere (Butsch, 2007; Calhoun & et al, 1992; Dahlgren, 2006), this thesis contributes to valuing radio as a productive gateway to research migrants’ construction of belonging, to inscribe a counterpoint in the field of minority media, and to debate conceptualizations of migratory categories and flows. Specifically, this thesis argues that the station fulfills similar roles to other minority radio initiatives but in ways that are specific to the population being catered to. Namely, unlike other minority stations, radio facilitates the process of transitioning between categories along on a continuum linking tourists and migrants. It also reflects and participates in strategies of reterritorialization that rest on functional and partial modes of incorporation. While contributing to sustain a translocality (Appadurai, 1996) it indexes and fosters a stance of connection that is symbolically and materially connected to the UK and other “neighborhoods” but is, simultaneously, oriented to engaging with the Algarve as “home”. Yet, besides reifying a British cultural identity, radio’s oral, repetitive and ephemeral discourse particularly trivializes the reproduction of an ambivalent stance of connection with place that is shared by other “expats”. This dynamic is related to migratory projects driven by social imaginaries fostered by international media that stimulate the search for idealized ways of living, which the radio associates with the Algarve. While recurrently localizing and validating the narrative projecting an idealized “good life”, radio amplifies dynamics among migrants that seem to reaffirm the migratory move as a good choice.
Resumo:
RESUMO: Objetivo Principal • Determinar a consistência da utilização dos instrumentos de avaliação da capacidade intelectual – escalas de Griffiths e WISC III – no enquadramento dos domínios e dos qualificadores da CIF-CJ, restrita às funções mentais do corpo. Objetivo secundário: • Estudar a efetividade e concordância inter-observador da aplicação da CIF, com base na leitura dos dados obtidos em avaliação efetuada com os instrumentos referidos, por duas observadoras independentes, em contexto de articulação saúde, respetivamente educação e segurança social Métodos • Estudo observacional, descritivo, transversal e prospetivo. • Foi estudada uma amostra de conveniência 355 crianças, num período de três anos (Maio de 2010 a 30 de Abril de 2013), com patologia da área da pediatria do neurodesenvolvimento (total de 4000 consultas) no Centro de Desenvolvimento (CD) do Hospital de Dona Estefânia (HDE), Centro Hospitalar de Lisboa Central, EPE (CHLC, EPE). • Critérios de inclusão: crianças de ambos os sexos, observadas no CD do HDE, CHLC (primeiras consultas e consultas de reavaliação) com idade ≥12 meses e ≤17 anos e incapacidade intelectual definida de acordo com os critérios da DSM-IV-TR, DSM 5 e CID-10. • Critérios de exclusão: crianças com autismo, perturbações específicas da linguagem, hiperatividade, défice de atenção e concentração, défices sensoriais congénitos (baixa visão e ou audição), ou com outros diagnósticos de perturbações de neurodesenvolvimento. • O estudo teve duas fases: na primeira, a investigadora principal colheu ou atualizou a história clínica, observou clinicamente as crianças solicitando os exames complementares considerados necessários e foi efetuada avaliação psicológica com os instrumentos adiante descritos, pela mesma psicóloga clínica, devidamente credenciada, e com larga experiência nas escalas referidas. Com base nos dados colhidos, quer por observação direta, quer através dos resultados das escalas Griffiths e WISC – III, a investigadora aplicou a CIF-CJ, circunscrita aos domínios e funções (variáveis): 1. FUNÇÕESMENTAIS GLOBAIS (b110- Funções da consciência, b114- Funções da orientação no espaço e no tempo, b117 – Funções intelectuais, b122- Funções psicossociais globais, b125- Funções intrapessoais, b126- Funções do temperamento e da personalidade); 2.FUNÇÕES MENTAIS ESPECÌFICAS (b140- funções da atenção, b147- Funções psicomotoras, b152- Funções emocionais, b156- Funções da perceção, b163- Funções cognitivas básicas, b164- Funções cognitivas de nível superior, b167- Funções mentais da linguagem 3. FUNÇÕES DA VOZ E DA FALA (b320- Funções da articulação, b330- Funções da fluência e do ritmo da fala). Numa segunda fase, foi solicitada a colaboração de duas co-investigadoras, com formação específica nas escalas utilizadas e na CIF-CJ, a aplicação da CIF nos mesmos domínios e funções. Estas observadoras não efetuaram observações diretas das crianças envolvidas. • Para efetuar a análise estatística e analisar a relação entre os qualificadores (0 a 4) das variáveis da CIF em estudo (b117, b122, b147, b163, b164, b167, b320 e b330) e os instrumentos psicométricos (escalas de Griffiths e WISC III), que constitui a primeira parte do estudo, recorreu-se à técnica estatística não paramétrica do coeficiente de correlação de Spearman, que quantifica a intensidade e sinal da eventual correlação existente entre as variáveis em estudo. • Para determinar as correlações referentes à segunda parte do estudo, foram utilizados os programas SPSS®, (IBM SPSS Statistics) e Statistica® (StatSoft, Inc., 2011). STATISTICA (data analysis software system, version 10. www.statsoft.com.), tendo-se dado preferência aos gráficos deste último. Resultados 1. Observou-se um predomínio do sexo masculino (relação de 1:1,9); relativamente à idade no momento de avaliação, 242 crianças (68,1%) tinham entre zero e seis anos e, dentro destas, a maioria (189) situava-se entre os três e os seis anos. 2. De acordo com a DSM-IV e DSM-5, 261 (73,4%) crianças apresentavam incapacidade intelectual ligeira. 3. A avaliação da competência intelectual pelas escalas de Ruth Griffiths e WISC III (QI), revelaram correlação negativa predominantemente forte e muito forte (índice de Spearman) com os qualificadores das funções do corpo estudadas (funções mentais, mentais específicas e da voz). Os resultados obtidos pela co-investigadora A foram sobreponíveis aos da investigadora principal. Os resultados obtidos pela co-investigadora B revelaram correlação negativa moderada e forte, correlação inferior à da investigadora principal; Conclusões Os resultados permitem inferir que as escalas de Ruth Griffiths e WISC-III são instrumentos adequados para caracterizar a incapacidade intelectual na CIF-CJ; a concordância inter-observador, moderada, nos qualificadores atribuídos nas funções em análise pela investigadora e co-investigadoras, permite concluir que as escalas de Ruth Griffiths e WISC IIIl são bons instrumentos para caracterizar os qualificadores nos domínios e funções estudados, por diferentes grupos de profissionais ligados à infância. Subsistem dificuldades na diferenciação entre qualificadores, designadamente entre os qualificadores 1 e 2, o que tem necessariamente implicações na elegibilidade das crianças para os apoios preconizados pelo DL 3/2008. ------------------------ ABSTRACT: Main objective • To determine the consistency of the use of assessment tools for intellectual ability - Griffiths and WISC III scales - in the context of domains and qualifiers for the ICF-CY, restricted to the mental functions of the body. Secondary objective • Studying the effectiveness and inter-observer concordance concerning the application of the ICF, based on the data recovered from the assessment made with the mentioned instruments, carried out by two independent observers including their perspective on health, education and social security. Methods • Observational, descriptive, cross-sectional and prospective study. • A convenience sample of 355 children was studied over a period of three years (May 2010 to April 2013), with a pathology in the area of pediatric neurodevelopment – intellectual disability (total of 4000 consultations, including first consultations and revaluations) were observed in the Development Centre (CD) in Hospital de Dona Estefânia (HDE), Centro Hospitalar de Lisboa Central, EPE (CHLC). • Inclusion criteria: children of both sexes aged ≥12 months and years ≤17 and intellectual disability defined according to the criteria in the DSM-IV-TR, DSM 5 and ICD-10. • Exclusion criteria: children with autism; specific language impairment, hyperactivity; attention deficit disorder; severe birth sensory deficits (eg, impaired vision and hearing); amongst other diagnoses for neurodevelopmental disorders. • The study was conducted in two phases: in the first phase the principal investigator collected or updated medical history, clinically observed children requesting additional investigations if she deemed necessary. Psychological evaluation was performed by a single, duly licensed clinical psychologist with extensive experience in the referred scales using the instruments described below. Based on data collected, either by direct observation or through the results of Griffiths scales and WISC - III, the researcher applied the ICF-CY confined to the following fields and functions (variables): 1. GLOBAL MENTAL FUNCTIONS (b110- functions of consciousness, b114- Functions referring to space and time orientation , b117 - intellectual functions, b122- global psychosocial functions, b125- intrapersonal functions, b126- functions related to temperament and personality); 2. SPECIFIC MENTAL FUNCTIONS ( b140- attention functions, b147-psychomotor functions, b152- Emotional functions, b156- perception functions, b163- basic cognitive functions and cognitive functions b164- top level b167- language related mental functions. ) 3. VOICE AND SPEECH FUNCTIONS (b320-articulation functions, b330- fluency and rhythm of speech functions). • In the second phase, two co-investigators, with specific training on the scales used and the ICF-CY have applied the ICF in the domains and functions mentioned above, based on the scales results. These co-investigators did not make any direct observation of the studied children. • To perform the statistical analysis and analyze the relationship between the qualifiers (0-4) of the variables in the ICF study (b117, b122, b147, B163, B164, b167, b320 and B330) and psychometric instruments (Griffiths scale and WISC III), which is the first part of the study, the statistical technique of non-parametric Spearman correlation coefficient was used, which quantifies the strength and sign of the possible correlation between the variables under study. • For submission of correlations related to the second part of the study, SPSS (IBM SPSS) and Statistica (StatSoft, Inc., 2011) programs were used. STATISTICA (data analysis software system, version 10 www.statsoft.com.). Preference was given to graphs computed in Statistica. Results • Male predominated (ratio of 1: 1.9). 242 children (68.1% of the sample) were aged between zero and six years and, among these, the majority (189) was aged largest number between three and six years. • According to the DSM-IV and DSM-5, 261 (73.4%) children had mild intellectual disability. The correlation between the assessment of intellectual competence by Ruth Griffiths scales and WISC III (QI), was predominantly negative strong and very strong correlation with the qualifiers of body functions studied (specific mental functions, mental and voice functions using Spearman index). The levels of correlation obtained by the co-investigatores were in agreeance with the results from the principal investigator. The results obtained by co-investigator B showed moderate to strong negative correlation, levels that were lower to the those registered by the principal investigator; Conclusions These results indicate that Ruth Griffiths and WISC-III scales are adequate tools to characterize intellectual disability in the ICF-CY; moderate inter-observer agreement in the qualifiers assigned the functions under analysis by the researcher and co-researchers, shows that the scales are also good tools to measure CIF qualifyers by diferent technicians with different professional orientations, related to children. However, there are still difficulties in differentiating qualifiers, namely between qualifiers 1/2 and 3/4, which necessarily has implications for the eligibility of children for the state support advocated by the Portuguese Decret Law 3/2008.
Resumo:
Introduction. The genera Enterococcus, Staphylococcus and Streptococcus are recognized as important Gram-positive human pathogens. The aim of this study was to evaluate the performance of Vitek 2 in identifying Gram-positive cocci and their antimicrobial susceptibilities. Methods. One hundred four isolates were analyzed to determine the accuracy of the automated system for identifying the bacteria and their susceptibility to oxacillin and vancomycin. Results. The system correctly identified 77.9% and 97.1% of the isolates at the species and genus levels, respectively. Additionally, 81.8% of the Vitek 2 results agreed with the known antimicrobial susceptibility profiles. Conclusion. Vitek 2 correctly identified the commonly isolated strains; however, the limitations of the method may lead to ambiguous findings.
Resumo:
Software Product Line (SPL) engineering aims at achieving efficient development of software products in a specific domain. New products are obtained via a process which entails creating a new configuration specifying the desired product’s features. This configuration must necessarily conform to a variability model, that describes the scope of the SPL, or else it is not viable. To ensure this, configuration tools are used that do not allow invalid configurations to be expressed. A different concern, however, is making sure that a product addresses the stakeholders’ needs as best as possible. The stakeholders may not be experts on the domain, so they may have unrealistic expectations. Also, the scope of the SPL is determined not only by the domain but also by limitations of the development platforms. It is therefore possible that the desired set of features goes beyond what is possible to currently create with the SPL. This means that configuration tools should provide support not only for creating valid products, but also for improving satisfaction of user concerns. We address this goal by providing a user-centric configuration process that offers suggestions during the configuration process, based on the use of soft constraints, and identifying and explaining potential conflicts that may arise. Suggestions help mitigating stakeholder uncertainty and poor domain knowledge, by helping them address well known and desirable domain-related concerns. On the other hand, automated conflict identification and explanation helps the stakeholders to understand the trade-offs required for realizing their vision, allowing informed resolution of conflicts. Additionally, we propose a prototype-based approach to configuration, that addresses the order-dependency issues by allowing the complete (or partial) specification of the features in a single step. A subsequent resolution process will then identify possible repairs, or trade-offs, that may be required for viabilization.
Resumo:
Existing wireless networks are characterized by a fixed spectrum assignment policy. However, the scarcity of available spectrum and its inefficient usage demands for a new communication paradigm to exploit the existing spectrum opportunistically. Future Cognitive Radio (CR) devices should be able to sense unoccupied spectrum and will allow the deployment of real opportunistic networks. Still, traditional Physical (PHY) and Medium Access Control (MAC) protocols are not suitable for this new type of networks because they are optimized to operate over fixed assigned frequency bands. Therefore, novel PHY-MAC cross-layer protocols should be developed to cope with the specific features of opportunistic networks. This thesis is mainly focused on the design and evaluation of MAC protocols for Decentralized Cognitive Radio Networks (DCRNs). It starts with a characterization of the spectrum sensing framework based on the Energy-Based Sensing (EBS) technique considering multiple scenarios. Then, guided by the sensing results obtained by the aforementioned technique, we present two novel decentralized CR MAC schemes: the first one designed to operate in single-channel scenarios and the second one to be used in multichannel scenarios. Analytical models for the network goodput, packet service time and individual transmission probability are derived and used to compute the performance of both protocols. Simulation results assess the accuracy of the analytical models as well as the benefits of the proposed CR MAC schemes.
Resumo:
Os estudos da satisfação e lealdade do cliente em ambiente Business-to-Business têm emergido devido ao interesse práctico e académico. Recorreu-se a um caso práctico de uma empresa de software internacional, ESRI, a operar em Portugal com modelo de negócio B2B e comportamento de compra extensivo. Desenvolveu-se um modelo estrutural com 11 variáveis latentes: lealdade; satisfação; imagem; atmosfera; cooperação; adaptação; processos; tecnologia; orientação ao cliente; competências; colaboradores e comunicação. Foram analisadas 304 respostas ao questionário de satisfação e de seguida aplicou-se o modelo a seis grupos de clientes segmentados de acordo com a contribuição do cliente para as receitas e o comportamento no processo de decisão de compra. Recorreu-se a modelos SEM (Structural Equation Modelling) com estimação dos parâmetros através da metodologia PLS (partial Least Squares). Os resultados mostram nos seis segmentos, que os valores da empresa, a cooperação através da competência dos colaboradores e da orientação ao cliente e a tecnologia são factores mais importantes para a satisfação e lealdade dos clientes.
Resumo:
In order to investigate the out-of-plane behaviour of masonry infill walls, quasi-static testing was performed on a masonry infill walls built inside a reinforced concrete frame by means of an airbag system to apply the uniform out-of-plane load to each component of the infill. The main advantage of this testing setup is that the out-of-plane loading can be applied more uniformly in the walls, contrarily to point load configuration. The test was performed under displacement control by selecting the mid-point of the infill as control point. Input and output air in the airbag was controlled by using a software to apply a specific displacement in the control point of the infill wall. The effect of the distance between the reaction frame of the airbag and the masonry infill on the effective contact area was previously analysed. Four load cells were attached to the reaction frame to measure the out-of-plane force. The effective contact area of the airbag was calculated by dividing the load measured in load cells by the pressure inside the airbag. When the distance between the reaction walls and the masonry infill wall is smaller, the effective area is closer to the nominal area of the airbag. Deformation and crack patterns of the infill confirm the formation of arching mechanism and two-way bending of the masonry infill. Until collapse of the horizontal interface between infill and upper beam in RC frame, the infill bends in two directions but the failure of that interface which is known as weakest interface due to difficulties in filling the mortar between bricks of last row and upper beam results in the crack opening trough a well-defined path and the consequent collapse of the infill.
Resumo:
Seismic investigations of typical south European masonry infilled frames were performed by testing two reduced scale specimens: one in the in-plane direction and another in the out-ofplane direction. Information about geometry and reinforcement scheme of those structures constructed in 1980s were obtained by [1]. The specimen to be tested in the in-plane direction was constructed as double leaf masonry while the specimen for testing in the out-of-plane direction is constructed with only its exterior leaf since the recent earthquakes have highlighted the vulnerability of the external leaf of the infills in out-of-plane direction [2]. The tests were performed by applying the pre-defined values of displacements in the in-plane and out-of-plane directions in the control points. For in-plane testing it was done by hydraulic actuator and for out-of-plane testing through the application of an airbag. Input and output air in the airbag was controlled by using a software to apply a specific displacement in the control point of the infill wall. Mid-point of the infill was assumed as a control point for outof- plane testing. Deformation and crack patterns of the infill confirm the formation of two-way arching mechanism of the masonry infill until collapse of the upper horizontal interface between infill and frame which is known as weakest interface due to difficulties in filling the mortar between bricks of last row and upper beam. This results in the crack opening through a welldefined path and the consequent collapse of the infill.
Resumo:
In the past decade, the research community has been dedicating considerable effort into indoor positioning systems based on Wi-Fi fingerprinting techniques, mainly due to their capability to exploit existing infrastructures. Crowdsourcing approaches, also known as organic, have been proposed recently to address the problem of creating and maintaining the corresponding radio maps. In these organic systems, the users of the system build the radio map themselves while using it to estimate their own position/location. However, most of these collaborative methods, proposed by several authors, assume that all the users are honest and committed to contribute to a good quality radio map. In this paper we assess the quality of a radio map built collaboratively and propose a method to classify the credibility of individual contributions and the reputation of individual users. Experimental results are presented for an organic indoor location system that has been used by more than one hundred users over a period of around 12 months.
Resumo:
This work was supported by FCT (Fundação para a Ciência e Tecnologia) within Project Scope (UID/CEC/00319/2013), by LIP (Laboratório de Instrumentação e Física Experimental de Partículas) and by Project Search-ON2 (NORTE-07-0162- FEDER-000086), co-funded by the North Portugal Regional Operational Programme (ON.2 - O Novo Norte), under the National Strategic Reference Framework, through the European Regional Development Fund.