991 resultados para GPU - graphics processing unit


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In the present paper we consider a differentiated Stackelberg model, when the leader firm engages in an R&D process that gives an endogenous cost-reducing innovation. The aim is to study the licensing of the cost-reduction by a per-unit royalty and a fixed-fee. We analyse the implications of these types of licensing contracts over the R&D effort, the profits of the firms, the consumer surplus and the social welfare. By using comparative static analysis, we conclude that the degree of the differentiation of the goods plays an important role in the results.

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The process of visually exploring underwater environments is still a complex problem. Underwater vision systems require complementary means of sensor information to help overcome water disturbances. This work proposes the development of calibration methods for a structured light based system consisting on a camera and a laser with a line beam. Two different calibration procedures that require only two images from different viewpoints were developed and tested in dry and underwater environments. Results obtained show, an accurate calibration for the camera/projector pair with errors close to 1 mm even in the presence of a small stereos baseline.

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The authors analyzed 704 transthoracic echocardiographic (TTE) examinations, performed routinely to all admitted patients to a general 16-bed Intensive Care Unit (ICU) during an 18-month period. Data acquisition and prevalence of abnormalities of cardiac structures and function were assessed, as well as the new, previously unknown severe diagnoses. A TTE was performed within the first 24 h of admission on 704 consecutive patients, with a mean age of 61.5+/-17.5 years, ICU stay of 10.6+/-17.1 days, APACHE II 22.6+/-8.9, and SAPS II 52.7+/-20.4. In four patients, TTE could not be performed. Left ventricular (LV) dimensions were quantified in 689 (97.8%) patients, and LV function in 670 (95.2%) patients. Cardiac output (CO) was determined in 610 (86.7%), and mitral E/A in 399 (85.9% of patients in sinus rhythm). Echocardiographic abnormalities were detected in 234 (33%) patients, the most common being left atrial (LA) enlargement (n=163), and LV dysfunction (n=132). Patients with these alterations were older (66+/-16.5 vs 58.1+/-17.4, p<0.001), presented a higher APACHE II score (24.4+/-8.7 vs 21.1+/-8.9, p<0.001), and had a higher mortality rate (40.1% vs 25.4%, p<0.001). Severe, previously unknown echocardiographic diagnoses were detected in 53 (7.5%) patients; the most frequent condition was severe LV dysfunction. Through a multivariate logistic regression analysis, it was determined that mortality was affected by tricuspid regurgitation (p=0.016, CI 1.007-1.016) and ICU stay (p<0.001, CI 1-1.019). We conclude that TTE can detect most cardiac structures in a general ICU. One-third of the patients studied presented cardiac structural or functional alterations and 7.5% severe previously unknown diagnoses.

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Development and standardization of reliable methods for detection of Mycobacterium tuberculosis in clinical samples is an important goal in laboratories throughout the world. In this work, lung and spleen fragments from a patient who died with the diagnosis of miliary tuberculosis were used to evaluate the influence of the type of fixative as well as the fixation and paraffin inclusion protocols on PCR performance in paraffin embedded specimens. Tissue fragments were fixed for four h to 48 h, using either 10% non-buffered or 10% buffered formalin, and embedded in pure paraffin or paraffin mixed with bee wax. Specimens were submitted to PCR for amplification of the human beta-actin gene and separately for amplification of the insertion sequence IS6110, specific from the M. tuberculosis complex. Amplification of the beta-actin gene was positive in all samples. No amplicons were generated by PCR-IS6110 when lung tissue fragments were fixed using 10% non-buffered formalin and were embedded in paraffin containing bee wax. In conclusion, combined inhibitory factors interfere in the detection of M. tuberculosis in stored material. It is important to control these inhibitory factors in order to implement molecular diagnosis in pathology laboratories.

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In this paper we study several natural and man-made complex phenomena in the perspective of dynamical systems. For each class of phenomena, the system outputs are time-series records obtained in identical conditions. The time-series are viewed as manifestations of the system behavior and are processed for analyzing the system dynamics. First, we use the Fourier transform to process the data and we approximate the amplitude spectra by means of power law functions. We interpret the power law parameters as a phenomenological signature of the system dynamics. Second, we adopt the techniques of non-hierarchical clustering and multidimensional scaling to visualize hidden relationships between the complex phenomena. Third, we propose a vector field based analogy to interpret the patterns unveiled by the PL parameters.

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These are the proceedings for the eighth national conference on XML, its Associated Technologies and its Applications (XATA'2010). The paper selection resulted in 33% of papers accepted as full papers, and 33% of papers accepted as short papers. While these two types of papers were distinguish during the conference, and they had different talk duration, they all had the same limit of 12 pages. We are happy that the selected papers focus both aspects of the conference: XML technologies, and XML applications. In the first group we can include the articles on parsing and transformation technologies, like “Processing XML: a rewriting system approach", “Visual Programming of XSLT from examples", “A Refactoring Model for XML Documents", “A Performance based Approach for Processing Large XML Files in Multicore Machines", “XML to paper publishing with manual intervention" and “Parsing XML Documents in Java using Annotations". XML-core related papers are also available, focusing XML tools testing on “Test::XML::Generator: Generating XML for Unit Testing" and “XML Archive for Testing: a benchmark for GuessXQ". XML as the base for application development is also present, being discussed on different areas, like “Web Service for Interactive Products and Orders Configuration", “XML Description for Automata Manipulations", “Integration of repositories in Moodle", “XML, Annotations and Database: a Comparative Study of Metadata Definition Strategies for Frameworks", “CardioML: Integrating Personal Cardiac Information for Ubiquous Diagnosis and Analysis", “A Semantic Representation of Users Emotions when Watching Videos" and “Integrating SVG and SMIL in DAISY DTB production to enhance the contents accessibility in the Open Library for Higher Education". The wide spread of subjects makes us believe that for the time being XML is here to stay what enhances the importance of gathering this community to discuss related science and technology. Small conferences are traversing a bad period. Authors look for impact and numbers and only submit their works to big conferences sponsored by the right institutions. However the group of people behind this conference still believes that spaces like this should be preserved and maintained. This 8th gathering marks the beginning of a new cycle. We know who we are, what is our identity and we will keep working to preserve that. We hope the publication containing the works of this year's edition will catch the same attention and interest of the previous editions and above all that this publication helps in some other's work. Finally, we would like to thank all authors for their work and interest in the conference, and to the scientific committee members for their review work.

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Dissertação para obtenção do Grau de Mestre em Engenharia Mecânica

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The integration of wind power in eletricity generation brings new challenges to unit commitment due to the random nature of wind speed. For this particular optimisation problem, wind uncertainty has been handled in practice by means of conservative stochastic scenario-based optimisation models, or through additional operating reserve settings. However, generation companies may have different attitudes towards operating costs, load curtailment, or waste of wind energy, when considering the risk caused by wind power variability. Therefore, alternative and possibly more adequate approaches should be explored. This work is divided in two main parts. Firstly we survey the main formulations presented in the literature for the integration of wind power in the unit commitment problem (UCP) and present an alternative model for the wind-thermal unit commitment. We make use of the utility theory concepts to develop a multi-criteria stochastic model. The objectives considered are the minimisation of costs, load curtailment and waste of wind energy. Those are represented by individual utility functions and aggregated in a single additive utility function. This last function is adequately linearised leading to a mixed-integer linear program (MILP) model that can be tackled by general-purpose solvers in order to find the most preferred solution. In the second part we discuss the integration of pumped-storage hydro (PSH) units in the UCP with large wind penetration. Those units can provide extra flexibility by using wind energy to pump and store water in the form of potential energy that can be generated after during peak load periods. PSH units are added to the first model, yielding a MILP model with wind-hydro-thermal coordination. Results showed that the proposed methodology is able to reflect the risk profiles of decision makers for both models. By including PSH units, the results are significantly improved.

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INTRODUCTION: Community-associated methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a pathogen in individuals without traditional risk factors. MATERIAL AND METHODS: MRSA nasal carriage was assessed in individuals consulting at a Primary Health Unit in Brazil. RESULTS: A total of 336 individuals were included: 136 were tested only for MRSA and 200 for any S. aureus. No MRSA was found among the 336 individuals and 23 (11.5%) of 200 were colonized by S. aureus. DISCUSSION: Low prevalence rates have been found in non-hospitalized individuals, but MRSA surveillance should be encouraged to monitor clinical and molecular epidemiology of CA- MRSA.

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In children, vertical transmission is the main form of HIV infection. Our aim was to determine the prevalence of HIV-1 vertical transmission in mother-infant pairs in a public maternity ward in Presidente Prudente, SP. Additionally; we sought to identify characteristics associated with this form of transmission. The files of 86 HIV-1-infected mothers and their newborns referred to a Public Hospital from March 2002 to March 2007 were analyzed. The HIV-1-RNA viral load of the newborns was determined by bDNA. The HIV-1 vertical-transmission rate was 4.6%. Children that were born in the pre-term period and breastfed were at a higher risk of HIV-1 infection (p = 0.005 and p = 0.017 respectively) than children born at term and not breastfed. Prophylactic therapy with zidovudine after birth for newborns was associated with a lower risk of infection (p = 0.003). The number of newborns weighing < 2,500 g was significantly higher for infected children (p = 0.008) than for non-infected newborns. About 22.9% of mothers did not know the HIV-1 status of their newborns eight months after delivery. The study suggests that it is necessary to increase the identification of HIV-1 infection in pregnant women and their newborns as well as to offer and explain the benefits of ARV prophylaxis.

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Thesis submitted in the fulfillment of the requirements for the Degree of Master in Biomedical Engineering

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The enzyme-linked immunosorbent assay (ELISA) is the most widely used tool to detect anti-Toxocara IgG antibodies for both serodiagnostic and seroepidemiological surveys on human toxocariasis. In the last eight years a high prevalence of toxocariasis (32.2-56.0%) has been reported in children attending public health units from municipalities in the state of Paraná, Brazil. Therefore, the aim of this work was to compare the frequency found among the general child population with that of children attending a public pneumology service in Maringá, Paraná, Brazil and describe the laboratorial, clinical and epidemiological findings. The research was conducted at the Consórcio Público Intermunicipal de Saúde do Setentrião Paranaense (CISAMUSEP) from July 2009 to July 2010 among children aged between one and 15 years. From a total of 167 children studied, only 4.2% (7/167) tested positive for anti-Toxocara spp. IgG antibodies and presented mild eosinophilia (2/7), increased serum IgE levels (6/7) and a positive allergy test for mites (5/7). The presence of pets (dogs or cats) at home did not correlate with the seroprevalence. In conclusion, cases of toxocariasis involving the respiratory tract are rare in children attending a public health pneumology unit in the northwestern region of Paraná State, despite the high prevalence of this type of toxocariasis among the infantile population attending Basic Health Units in the same geographical area.

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Este trabalho teve como principal objetivo o estudo da simulação da unidade de destilação atmosférica e a vácuo da fábrica de óleos base da Petrogal, permitindo verificar que, uma vez conseguido um modelo num programa de simulação que traduz o comportamento real de um dado processo, é possível sem riscos operacionais avaliar o efeito da alteração das condições normais de funcionamento desse processo. O trabalho foi orientado pelo Eng.º Carlos Reis, no que diz respeito à empresa, e pelo Prof. Dr. Luís Silva, pelo ISEP. O trabalho foi dividido em duas partes, sendo a primeira direcionada à obtenção do novo crude a partir de dois crudes pesados e caracterização dessa mistura. Já a segunda parte reside na refinação deste novo crude através da plataforma Aspen Plus para obtenção do resíduo de vácuo, para posterior processamento na coluna de discos rotativos usando um método de separação por extração liquido-liquido. Estudaram-se as propriedades físicas dos fluidos e verificou-se que na destilação atmosférica as curvas de destilação encontram-se muito próximas comparativamente com os resultados obtidos pela empresa, enquanto na destilação a vácuo os valores encontram-se mais afastados, apresentando uma variação de 30ºC a 100ºC em relação aos valores obtidos pelo Petro-Sim. Com a finalidade de cumprir um dos objetivos em falta, irão ser realizadas futuramente simulações no extrator de discos rotativos para otimização do processo para crudes pesados, sendo os resultados facultados, posteriormente, à Petrogal. Durante a realização do trabalho foi atingido um modelo real representativo da unidade de destilação atmosférica e a vácuo da Petrogal, podendo obter-se resultados para qualquer tipo de crude, fazendo apenas variar o assay da corrente de alimentação.

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OBJECTIVE: The objective of the study was to develop a model for estimating patient 28-day in-hospital mortality using 2 different statistical approaches. DESIGN: The study was designed to develop an outcome prediction model for 28-day in-hospital mortality using (a) logistic regression with random effects and (b) a multilevel Cox proportional hazards model. SETTING: The study involved 305 intensive care units (ICUs) from the basic Simplified Acute Physiology Score (SAPS) 3 cohort. PATIENTS AND PARTICIPANTS: Patients (n = 17138) were from the SAPS 3 database with follow-up data pertaining to the first 28 days in hospital after ICU admission. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The database was divided randomly into 5 roughly equal-sized parts (at the ICU level). It was thus possible to run the model-building procedure 5 times, each time taking four fifths of the sample as a development set and the remaining fifth as the validation set. At 28 days after ICU admission, 19.98% of the patients were still in the hospital. Because of the different sampling space and outcome variables, both models presented a better fit in this sample than did the SAPS 3 admission score calibrated to vital status at hospital discharge, both on the general population and in major subgroups. CONCLUSIONS: Both statistical methods can be used to model the 28-day in-hospital mortality better than the SAPS 3 admission model. However, because the logistic regression approach is specifically designed to forecast 28-day mortality, and given the high uncertainty associated with the assumption of the proportionality of risks in the Cox model, the logistic regression approach proved to be superior.

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Uma nova área tecnológica está em crescente desenvolvimento. Esta área, denominada de internet das coisas, surge na necessidade de interligar vários objetos para uma melhoria a nível de serviços ou necessidades por parte dos utilizadores. Esta dissertação concentra-se numa área específica da tecnologia internet das coisas que é a sensorização. Esta rede de sensorização é implementada pelo projeto europeu denominado de Future Cities [1] onde se cria uma infraestrutura de investigação e validação de projetos e serviços inteligentes na cidade do Porto. O trabalho realizado nesta dissertação insere-se numa das plataformas existentes nessa rede de sensorização: a plataforma de sensores ambientais intitulada de UrbanSense. Estes sensores ambientais que estão incorporados em Data Collect Unit (DCU), também denominados por nós, medem variáveis ambientais tais como a temperatura, humidade, ozono e monóxido de carbono. No entanto, os nós têm recursos limitados em termos de energia, processamento e memória. Apesar das grandes evoluções a nível de armazenamento e de processamento, a nível energético, nomeadamente nas baterias, não existe ainda uma evolução tão notável, limitando a sua operacionalidade [2]. Esta tese foca-se, essencialmente, na melhoria do desempenho energético da rede de sensores UrbanSense. A principal contribuição é uma adaptação do protocolo de redes Ad Hoc OLSR (Optimized Link State Routing Protocol) para ser usado por nós alimentados a energia renovável, de forma a aumentar a vida útil dos nós da rede de sensorização. Com esta contribuição é possível obter um maior número de dados durante períodos de tempo mais longos, aproximadamente 10 horas relativamente às 7 horas anteriores, resultando numa maior recolha e envio dos mesmos com uma taxa superior, cerca de 500 KB/s. Existindo deste modo uma aproximação analítica dos vários parâmetros existentes na rede de sensorização. Contudo, o aumento do tempo de vida útil dos nós sensores com recurso à energia renovável, nomeadamente, energia solar, incrementa o seu peso e tamanho que limita a sua mobilidade. Com o referido acréscimo a determinar e a limitar a sua mobilidade exigindo, por isso, um planeamento prévio da sua localização. Numa primeira fase do trabalho analisou-se o consumo da DCU, visto serem estes a base na infraestrutura e comunicando entre si por WiFi ou 3G. Após uma análise dos protocolos de routing com iv suporte para parametrização energética, a escolha recaiu sobre o protocolo OLSR devido à maturidade e compatibilidade com o sistema atual da DCU, pois apesar de existirem outros protocolos, a implementação dos mesmos, não se encontram disponível como software aberto. Para a validação do trabalho realizado na presente dissertação, é realizado um ensaio prévio sem a energia renovável, para permitir caracterização de limitações do sistema. Com este ensaio, tornou-se possível verificar a compatibilidade entre os vários materiais e ajustamento de estratégias. Num segundo teste de validação é concretizado um ensaio real do sistema com 4 nós a comunicar, usando o protocolo com eficiência energética. O protocolo é avaliado em termos de aumento do tempo de vida útil do nó e da taxa de transferência. O desenvolvimento da análise e da adaptação do protocolo de rede Ad Hoc oferece uma maior longevidade em termos de tempo de vida útil, comparando ao que existe durante o processamento de envio de dados. Apesar do tempo de longevidade ser inferior, quando o parâmetro energético se encontra por omissão com o fator 3, a realização da adaptação do sistema conforme a energia, oferece uma taxa de transferência maior num período mais longo. Este é um fator favorável para a abertura de novos serviços de envio de dados em tempo real ou envio de ficheiros com um tamanho mais elevado.