959 resultados para DIMENSIONAL MODEL
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This book presents research in the field of Geophysics, particularly referring to principles, applications and emerging technologies. Table of Contents: Preface pp. i-xxi Environmental Geophysics: Techniques, advantages and limitations (Pantelis Soupios and Eleni Kokinou, Department of Environmental and Natural Resources Engineering, Technological Educational Institute of Crete, Dynamics of the Ocean Floor, Helmholtz Centre for Ocean Research Kiel, Geomar)pp i-xxi Application of Innovative Geophysical Techniques in Coastal Areas (V. Di Fiore, M. Punzo, D. Tarallo, and G. Cavuoto, Institute for Marine Coastal Environment, National Research Council, Naples)pp. i-xxi Marine Geophysics of the Naples Bay (Southern Tyrrhenian sea, Italy): Principles, Applications and Emerging Technologies (Gemma Aiello and Ennio Marsella, Institute for Marine Coastal Environment, National Research Council, Naples)pp. i-xxi Oceanic Oscillation Phenomena: Relation to Synchronization and Stochastic Resonance (Shinya Shimokawa and Tomonori Matsuura, National Research Institute for Earth Science and Disaster Prevention, Univ. of Toyama)pp. i-xxi Assessment of ocean variability in the Sicily Channel from a numerical three-dimensional model using EOFs decomposition (R. Sorgente, A. Olita, A.F. Drago, A. Ribotti, L. Fazioli, and C. Tedesco, Institute for Marine Coastal Environment, National Research Council, Oristano)pp. i-xxi Monitoring Test of Crack Opening in Volcanic Tuff (Coroglio Cliff. Italy) Using Distributed Optical Fiber Sensor (A. Minardo, A. Coscetta, M. Caccavale, G. Esposito, F. Matano, M. Sacchi, R. Somma, G. Zeni, and L. Zeni, Department of Industrial and Information Eng., Second University of Naples Aversa, Institute for Marine Coastal Environment, National Research Council Naples, National Institute for Geophysics and Volcanology, Osservatorio Vesuviano Naples, Institute for Electromagnetic Sensing of the Environment, National Research Council Naples)pp. i-xxi
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To understand the evolution of bipedalism among the homnoids in an ecological context we need to be able to estimate theenerrgetic cost of locomotion in fossil forms. Ideally such an estimate would be based entirely on morphology since, except for the rare instances where footprints are preserved, this is hte only primary source of evidence available. In this paper we use evolutionary robotics techniques (genetic algoritms, pattern generators and mechanical modeling) to produce a biomimentic simulation of bipedalism based on human body dimensions. The mechnaical simulation is a seven-segment, two-dimensional model with motive force provided by tension generators representing the major muscle groups acting around the lower-limb joints. Metabolic energy costs are calculated from the muscel model, and bipedal gait is generated using a finite-state pattern generator whose parameters are produced using a genetic algorithm with locomotor economy (maximum distance for a fixed energy cost) as the fitness criterion. The model is validated by comparing the values it generates with those for modern humans. The result (maximum efficiency of 200 J m-1) is within 15% of the experimentally derived value, which is very encouraging and suggests that this is a useful analytic technique for investigating the locomotor behaviour of fossil forms. Initial work suggests that in the future this technique could be used to estimate other locomotor parameters such as top speed. In addition, the animations produced by this technique are qualitatively very convincing, which suggests that this may also be a useful technique for visualizing bipedal locomotion.
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Osteotomy or bone cutting is a common procedure in orthopaedic surgery, mainly in the treatment of fractures and reconstructive surgery. However, the excessive heat produced during the bone drilling process is a problem that counters the benefits of this type of surgery, because it can result in thermal osteonecrosis, bone reabsorption and damage the osseointegration of implants. The analysis of different drilling parameters and materials can allow to decrease the temperature during the bone drilling process and contribute to a greater success of this kind of surgical interventions. The main goal of this study was to build a numerical three-dimensional model to simulate the drilling process considering the type of bone, the influence of cooling and the bone density of the different composite materials with similar mechanical properties to the human bone and generally used in experimental biomechanics. The numerical methodology was coupled with an experimental methodology. The use of cooling proved to be essential to decrease the material damage during the drilling process. It was concluded that the materials with less porosity and density present less damage in drilling process. The developed numerical model proved to be a great tool in this kind of analysis. © 2016, The Brazilian Society of Mechanical Sciences and Engineering.
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A literacia em diabetes parece ser uma das ferramentas fundamentais para combater o aumento de prevalência desta patologia crónica que tem crescido exponencialmente ao longo dos anos quer a nível mundial, quer a nível nacional. Com este estudo pretendeu-se avaliar o nível de literacia em diabetes nos estudantes do ensino superior público do concelho de Mirandela, para, em consequência, fornecer algumas diretrizes para a proposta de um projeto de intervenção nesta comunidade. Teve como objetivos específicos: validar o questionário dos conhecimentos da Diabetes (QCD); relacionar os níveis de conhecimento sobre diabetes com as variáveis sociodemográficas e clinicas. A amostra estudada compreende 432 alunos do ensino superior público do concelho de Mirandela que reponderam ao questionário no período de 15 de fevereiro a 18 de março de 2016. Verificou-se que a aplicação do questionário dos conhecimentos da diabetes (QCD; Sousa & McIntyre, 2003) que avalia os conhecimentos das pessoas acerca da diabetes e seu tratamento, parece ser aceitável na população em geral e o modelo bidimensional obtido com a análise fatorial confirmatória revelou bons índices de ajustamento. Os resultados indicaram um reduzido nível de literacia em diabetes na amostra de participantes e o seu desconhecimento está associado a mitos e falsos conceitos mais do que a incerteza; que o conhecimento na dimensão duração da doença era maior que na dimensão conhecimento global da diabetes (causas, controlo, tratamento e complicações); os alunos mais novos possuem mais conhecimento sobre a diabetes, o género feminino parece revelar maior conhecimento do que o masculino, que os alunos que residem no concelho de Mirandela apresentam menor conhecimento do que os restantes e que os alunos que possuem e residem com familiares com diabetes possuem mais conhecimento do que os outros, embora apresentem igualmente elevado desconhecimento por mitos e falsos conceitos. Conclui-se que existe uma necessidade de aposta em projetos educacionais comunitários para aumentar a literacia em diabetes.
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In this study, numerical simulation of the Caspian Sea circulation was performed using COHERENS three-dimensional numerical model and field data. The COHERENS three-dimensional model and FVCOM were performed under the effect of the wind driven force, and then the simulation results obtained were compared. Simulation modeling was performed at the Caspian Sea. Its horizontal grid size is approximately equal to 5 Km and 30 sigma levels were considered. The numerical simulation results indicate that the winds' driven-forces and temperature gradient are the most important driving force factors of the Caspian circulation pattern. One of the effects of wind-driven currents was the upwelling phenomenon that was formed in the eastern shores of the Caspian Sea in the summer. The simulation results also indicate that this phenomenon occurred at a depth less than 40 meters, and the vertical velocity in July and August was 10 meters and 7 meters respectively. During the upwelling phenomenon period the temperatures on the east coast compared to the west coast were about 5°C lower. In autumn and winter, the warm waters moved from the south east coast to the north and the cold waters moved from the west coast of the central Caspian toward the south. In the subsurface and deep layers, these movements were much more structured and caused strengthening of the anti-clockwise circulation in the area, especially in the central area of Caspian. The obtained results of the two models COHERENS and FVCOM performed under wind driven-force show a high coordination of the two models, and so the wind current circulation pattern for both models is almost identical.
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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Arquitetura e Urbanismo, Programa de Pós-Graduação em Arquitetura e Urbanismo, 2015.
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Dissertação de Mestrado apresentada no ISPA – Instituto Universitário para obtenção do grau de Mestre em Psicologia especialidade em Psicologia Social e das Organizações
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O sono é uma necessidade básica que influencia e é simultaneamente influenciada pela diversidade de atividades, papéis e contextos de vida, assumindo particular importância nos adolescentes. Apresenta-se um estudo com 400 alunos do 9º e 11º ano de escolaridade, de duas escolas da região de Lisboa, avaliados através do Questionário Sobre Sono para Adolescentes – QSSA. Os resultados quantitativos da caracterização do sono incidiram sobre hábitos, auto perceções e conhecimentos. Da exploração qualitativa dos fatores invocados por uma subamostra de 100 adolescentes como fundamento das suas auto perceções, emergiram as categorias de qualidade, importância e atitudes. Com base nestes resultados, propõe-se um modelo tridimensional acerca do sono dos adolescentes que contempla hábitos de sono, fatores pessoais e fatores ambientais.
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Se describe la variante homocigota c.320-2A>G de TGM1 en dos hermanas con ictiosis congénita autosómica recesiva. El clonaje de los transcritos generados por esta variante permitió identificar tres mecanismos moleculares de splicing alternativos.
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During its history, several significant earthquakes have shaken the Lower Tagus Valley (Portugal). These earthquakes were destructive; some strong earthquakes were produced by large ruptures in offshore structures located southwest of the Portuguese coastline, and other moderate earthquakes were produced by local faults. In recent years, several studies have successfully obtained strong-ground motion syntheses for the Lower Tagus Valley using the finite difference method. To confirm the velocity model of this sedimentary basin obtained from geophysical and geological data, we analysed the ambient seismic noise measurements by applying the horizontal to vertical spectral ratio (HVSR) method. This study reveals the dependence of the frequency and amplitude of the low-frequency (HVSR) peaks (0.2–2 Hz) on the sediment thickness. We have obtained the depth of the Cenozoic basement along a profile transversal to the basin by the inversion of these ratios, imposing constraints from seismic reflection, boreholes, seismic sounding and gravimetric and magnetic potentials. This technique enables us to improve the existing three-dimensional model of the Lower Tagus Valley structure. The improved model will be decisive for the improvement of strong motion predictions in the earthquake hazard analysis of this highly populated basin. The methodology discussed can be applied to any other sedimentary basin.
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In digital markets personal information is pervasively collected by firms. In the first chapter I study data ownership and product customization when there is exclusive access to non rival but excludable data about consumer preferences. I show that an incumbent firm does not have an incentive to sell an exclusively held dataset with a rival firm, but instead it has an incentive to trade a customizing technology with the other firm. In the second chapter I investigate the effects of consumer information on the intensity of competition. In a two dimensional model of product differentiation, firms use information on preferences to practice price discrimination. I contrast a full privacy and a no privacy benchmark with a regime in which firms are able to target consumers only partially. When data is partially informative, firms are always better-off with price discrimination and an exclusive access to user data is not necessarily a competition policy concern. From a consumer protection perspective, the policy recommendation is that the regulator should promote either no privacy or full privacy. In the third chapter I introduce a data broker that observes either only one or both dimensions of consumer information and sells this data to competing firms for price discrimination purposes. When the seller exogenously holds a partially informative dataset, an exclusive allocation arises. Instead, when the dataset held is fully informative, the data broker trades information non exclusively but each competitor acquires consumer data on a different dimension. When data collection is made endogenous, non exclusivity is robust if collection costs are not too high. The competition policy suggestion is that exclusivity should not be banned per se, but it is data differentiation in equilibrium that rises market power in competitive markets. Upstream competition is sufficient to ensure that both firms get access to consumer information.
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Nowadays the development of new Internal Combustion Engines is mainly driven by the need to reduce tailpipe emissions of pollutants, Green-House Gases and avoid the fossil fuels wasting. The design of dimension and shape of the combustion chamber together with the implementation of different injection strategies e.g., injection timing, spray targeting, higher injection pressure, play a key role in the accomplishment of the aforementioned targets. As far as the match between the fuel injection and evaporation and the combustion chamber shape is concerned, the assessment of the interaction between the liquid fuel spray and the engine walls in gasoline direct injection engines is crucial. The use of numerical simulations is an acknowledged technique to support the study of new technological solutions such as the design of new gasoline blends and of tailored injection strategies to pursue the target mixture formation. The current simulation framework lacks a well-defined best practice for the liquid fuel spray interaction simulation, which is a complex multi-physics problem. This thesis deals with the development of robust methodologies to approach the numerical simulation of the liquid fuel spray interaction with walls and lubricants. The accomplishment of this task was divided into three tasks: i) setup and validation of spray-wall impingement three-dimensional CFD spray simulations; ii) development of a one-dimensional model describing the liquid fuel – lubricant oil interaction; iii) development of a machine learning based algorithm aimed to define which mixture of known pure components mimics the physical behaviour of the real gasoline for the simulation of the liquid fuel spray interaction.
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The aggregation of interacting Brownian particles in sheared concentrated suspensions is an important issue in colloid and soft matter science per se. Also, it serves as a model to understand biochemical reactions occurring in vivo where both crowding and shear play an important role. We present an effective medium approach within the Smoluchowski equation with shear which allows one to calculate the encounter kinetics through a potential barrier under shear at arbitrary colloid concentrations. Experiments on a model colloidal system in simple shear flow support the validity of the model in the concentration range considered. By generalizing Kramers' rate theory to the presence of shear and collective hydrodynamics, our model explains the significant increase in the shear-induced reaction-limited aggregation kinetics upon increasing the colloid concentration.
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Using Monte Carlo simulations we investigate some new aspects of the phase diagram and the behavior of the diffusion coefficient in an associating lattice gas (ALG) model on different regions of the phase diagram. The ALG model combines a two dimensional lattice gas where particles interact through a soft core potential and orientational degrees of freedom. The competition between soft core potential and directional attractive forces results in a high density liquid phase, a low density liquid phase, and a gas phase. Besides anomalies in the behavior of the density with the temperature at constant pressure and of the diffusion coefficient with density at constant temperature are also found. The two liquid phases are separated by a coexistence line that ends in a bicritical point. The low density liquid phase is separated from the gas phase by a coexistence line that ends in tricritical point. The bicritical and tricritical points are linked by a critical lambda-line. The high density liquid phase and the fluid phases are separated by a second critical tau-line. We then investigate how the diffusion coefficient behaves on different regions of the chemical potential-temperature phase diagram. We find that diffusivity undergoes two types of dynamic transitions: a fragile-to-strong transition when the critical lambda-line is crossed by decreasing the temperature at a constant chemical potential; and a strong-to-strong transition when the critical tau-line is crossed by decreasing the temperature at a constant chemical potential.
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In the context of the 1/N expansion, the validity of the Slavnov-Taylor identity relating three- and two-point functions for the 2 + 1-dimensional noncommutative CP(N-1) model is investigated, up to subleading 1/N order, in the Landau gauge.