1,223 research outputs found

    Fast Distributed Computation of Distances in Networks

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    This paper presents a distributed algorithm to simultaneously compute the diameter, radius and node eccentricity in all nodes of a synchronous network. Such topological information may be useful as input to configure other algorithms. Previous approaches have been modular, progressing in sequential phases using building blocks such as BFS tree construction, thus incurring longer executions than strictly required. We present an algorithm that, by timely propagation of available estimations, achieves a faster convergence to the correct values. We show local criteria for detecting convergence in each node. The algorithm avoids the creation of BFS trees and simply manipulates sets of node ids and hop counts. For the worst scenario of variable start times, each node i with eccentricity ecc(i) can compute: the node eccentricity in diam(G)+ecc(i)+2 rounds; the diameter in 2*diam(G)+ecc(i)+2 rounds; and the radius in diam(G)+ecc(i)+2*radius(G) rounds.Comment: 12 page

    Como abordar uma instalação de domótica KNX para uma moradia?

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    A domótica pode ser entendida como o controlo automatizado das instalações técnicas existentes num edifício. No caso concreto de uma habitação, utilizando a tecnologia KNX podemos controlar, por exemplo: - iluminação; - estores e persianas; - sistemas de segurança; - gestão de energia; - sistemas de aquecimento, ventilação e ar condicionado (AVAC); - controlo remoto; - controlo áudio/vídeo; - etc.Como hoje em dia, aspetos como a segurança, eficiência energética, conforto e comunicação são cada vez mais uma exigência dos proprietários/utilizadores dos edifícios, não faz sentido continuar a abordar a execução de instalações elétricas do tipo convencional, sistemas de AVAC, alarmes e outros, sem que estes comuniquem entre si.Assim, justifica-se a apresentação ao cliente das instalações elétricas apoiadas numa solução de domótica KNX, o que possibilitará a integração e comunicação daqueles sistemas

    An algebraic approach to synthetic aperture sonar image reconstruction

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    A new approach for synthetic aperture image formation is presented in this paper. With the presented method image formation is regarded as a signal arrangement that can be described by a matrix. This method integrates the sonar platform motion in the image formation process but more importantly it acknowledges the non ideal data gathering process and implements means to mitigate these shortcomings. This method is illustrated with real data obtained in test mission in the Douro River, Portugal by a synthetic aperture sonar developed at the University of Porto

    Library for Simplified Timer Implementation using Standard C++

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    Temporization is a crucial aspects of control, automation and robotics systems. C++ is used in the development of such systems, especially if they are more complex and powerful. Because, the language and standard library do not support non-blocking timers with callbacks for event-driven programming, developers resort to libraries and frameworks that offer such functionality. However, their timer implementations are dependent on platform specificities and thus have more limited portability. C++11 has introduced features that enable standard implementations of timers. We propose a library that implements timers with simplified usage relatively to well-known libraries. The proposed library is contrasted with timers of two well know libraries, through a series of usage scenarios. We describe the design and provide performance measurements. The results show that it is faster and offers more accurate temporization.(undefined)info:eu-repo/semantics/publishedVersio

    Influence of vaccine-preventable diseases and HIV infection on demand for an infectious diseases service in Rio de Janeiro State, Brazil, over 22 years – Part II (1995-2016)

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    Patients’ data during daily clinical care are extremely important for improving the allocation of healthcare resources and for assessing healthcare demands. The prospective gathering of these data over decades allowed us to describe the trends of infectious diseases in a tertiary hospital. The results concerning the period between 1965 and 1994 described the exponential increase in the incidence of HIV infection and its important effects on our institutional mortality. The present study describes the demand for the same hospital between 1995 and 2016. There were 4,691 admissions and the main causes of admissions were, in descending order, HIV infection (1,312, 28.0%), noninfectious diseases (447, 9.5%), meningoencephalitis (432, 9.2%), soft tissue infections (427; 9.1%), tuberculosis (272, 5.8%), pneumonias (212, 4.5%) and leptospirosis (212, 4.5%). There were 864 readmissions; most due to HIV infections (65.2%). The institutional mortality fell from 16.9% in the first two years to 5.0% in the last two years of the study. The case-fatality rates among the HIV patients decreased from more than 40% to approximately 5% over the study period. In the last two decades, the hospital experienced a decrease in demand due to vaccine-preventable diseases. The demand for children has fallen and the demand for patients over the age of 50 has increased. These results reflect the improvement in public health standards over more than half a century and the positive effects of the National Immunization Program. They also illustrate the sharp decline in the HIV case-fatality rate after the introduction of combined antiretroviral therap

    Fungicide application technology for controlling the sugarcane orange rust

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    With the epidemic onset of the sugarcane orange rust, fungicide applications of the Strobilurins and Triazoles groups have become necessary in susceptible varieties. This study aimed at evaluating the operational conditions of fungicide application in sugarcane (SP81-3250 variety), in relation to the spray deposition on the upper canopy and the effectiveness of the orange rust control. Treatments consisted of two application volumes (30 L ha-1 or 40 L ha-1) and three nozzle deflection angles (0 º, 90 º or 135 º), plus a ground application at the rate of 200 L ha-1, sprayed with a uniform flat spray nozzle of air induction. The ground application resulted in the smallest and the greatest spray deposition on sugarcane leaves and on the soil, respectively. The aerial application at the rate of 30 L ha-1, sprayed by hollow cone nozzles, at a deflection angle of 135 º, provided the best sugarcane orange rust control. Tecnologia de aplicação de fungicidas no controle da ferrugem alaranjada da cana-de-açúcar -- Com o surgimento epidêmico da ferrugem alaranjada da cana-de-açúcar, aplicações de fungicidas dos grupos químicos Estrobilurinas e Triazóis tornaram-se necessárias para as variedades suscetíveis. Objetivou-se avaliar as condições operacionais de aplicação de fungicidas em cana-de-açúcar (variedade SP81-3250), no que se refere à deposição de calda no dossel superior e à efetividade do controle da ferrugem alaranjada. Os tratamentos consistiram de dois volumes de aplicação (30 L ha-1 ou 40 L ha-1) e três ângulos de deflexão das pontas (0 º, 90 º ou 135 º), além de uma aplicação terrestre à taxa de 200 L ha-1, pulverizada por meio de pontas de jato plano uniforme de indução de ar. A aplicação terrestre resultou na menor e maior deposição nas folhas de cana-de-açúcar e no solo, respectivamente. A aplicação aérea com taxa de 30 L ha-1, pulverizada por pontas de jato cônico vazio, com ângulo de deflexão de 135 º, proporcionou o melhor controle da ferrugem alaranjada da cana-de-açúcar

    Cefaléias de origem oftálmica

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    Isokinetic Evaluation After Two-stage Bicruciate Reconstruction.

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    To assess the functional balance of the knee after bicruciate reconstruction and its correlation with clinical score. 14 patients (11 men and three women), mean age 29.9±7.65 years, mean BMI 26.2±2.51 kg/m(2) underwent surgical reconstruction of the Posterior Cruciate Ligament (PCL) and Anterior Cruciate Ligament (ACL) in two stages, with a mean interval of 3 months between procedures. With a mean follow-up period of 27.33 months, the isokinetic knee analysis was performed at 60°/s and 180°/s and the Lysholm and Tegner scores were applied. The Lysholm score was 86.8±11.1 points and the Tegner score showed a deficit of 30% compared to pre-injury level. In isokinetic evaluation, the deficit of the operated quadriceps average torque was 17.05% at 60°/s and 12.16% at 180°/s, while the average flexor torque deficit was 3.43% at 60°/s and 5.82% at 180°/s. Although it was observed torque deficit between members, there were no statistical differences regarding the functional balance between hamstrings and quadriceps. Although the results of isokinetic evaluation has shown a functional balance of the knee (flexor-extensor), which may have contributed to the good subjective Lysholm score in the bicruciate two-stage reconstruction, two-stage reconstruction did not restore the pre-injury functional level. Level of Evidence IV, Case Series.2221-

    Estratégias de motivação na iniciação ao estudo do clarinete

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    Relatório de Estágio apresentado à Escola Superior de Artes Aplicadas do Instituto Politécnico de Castelo Branco para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ensino de Música - Instrumento e Música de Conjunto.A iniciação a um instrumento musical é um processo que requer bastante atenção por parte dos professores. Cabe a estes desenvolverem e aplicarem diferentes estratégias para incentivarem os seus alunos para a aprendizagem e o estudo do mesmo. Através de alguns fundamentos da Teoria da Aprendizagem Social de Albert Bandura e da Teoria da Aprendizagem de Jerome Bruner foram desenvolvidas estratégias que procuram desenvolver a motivação intrínseca dos alunos e promover a autonomia para o estudo individual. Ao longo deste projeto de investigação são apresentados os procedimentos aplicados a um grupo formado por três alunos que se encontravam a iniciar a sua aprendizagem. Trata-se assim de um estudo de caso que, devido à influência do investigador no decorrer das aulas observadas, possuiu um cariz construtivista. A partir da observação das aulas e da análise das entrevistas verificaram-se resultados positivos na aprendizagem dos alunos e um aumento da motivação e autonomia para o estudo do clarinete. Antes da apresentação do estudo de investigação, é realizada uma descrição e análise da Prática de Ensino Supervisionada que decorreu na Academia de Música de Castelo de Paiva durante o ano letivo 2014/2015.Abstract: Initiation to a musical instrument is a process that requires close attention from teachers. They should develop and implement different strategies to encourage their students to learn and the study the instrument. Through the application of some fundamentals of Social Learning Theory of Albert Bandura and Learning Theory of Jerome Bruner, strategies have been developed to encourage intrinsic motivation in students and promote autonomy for individual study. Over this research project are presented the procedures applied to a group of three students who were starting their learning. It is thus a case study that, due to the influence of the investigator during the observed classes, possesses a constructivist nature. From the observation of classes and analysis of interviews, positive results were verified in student learning and an increase of motivation and autonomy to study the clarinet was also observed. Before the presentation of the research study, a description and analysis is made of the Supervised Teaching Practice, which took place in Academia de Música de Castelo de Paiva during the school year of 2014/2015
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