Estudo de um evento de afloramento e ralaxamento na região costeira de Aveiro

Mestrado em Meteorologia e Oceanografia FísicaEste trabalho, realizado no âmbito do Mestrado em Meteorologia e Oceanografia Física da Universidade de Aveiro, surge ligado à campanha realizada pelo IPIMAR (NeoMav), a bordo dos Navios de Investigação Noruega e Tellina em Julho de 2007. Nele se faz uma análise dos dados recolhidos pelo CTDF a bordo dos dois navios, caracterizando os campos de temperatura, salinidade, densidade e concentração de clorofila-a na área mais costeira, ao largo de Aveiro, para o período de 2 a 7 de Julho de 2007. A informação recolhida por estes navios foi complementada com: i) uma configuração numérica de circulação, realizada com o modelo ROMS-AGRIF, com uma resolução aproximada de 900m, forçado em condições realistas; ii) dados obtidos por satélite para temperatura de superfície (da série NOAA, sensor AVHRR) e concentração de clorofila-a (sensor MODIS, satélite Terra). São estudadas as respostas da plataforma média e plataforma interior aos forçamentos atmosféricos que consistiram na alternância entre um regime de ventos de Norte, seguido de relaxamento e nova intensificação do vento de Norte, no Verão, na zona em estudo. As características mais marcantes são: a ascensão de água fria, durante o afloramento; o aparecimento de uma contracorrente para Norte na plataforma interior, junto à costa, durante o relaxamento; o aparecimento de uma frente que separa as águas afloradas mais frias das águas oceânicas mais quentes; a assinatura das descargas do rio Douro na salinidade, com uma pluma de água menos salgada a deslocar-se para Sul, associada ao jacto e para o largo, associada ao transporte de Ekman induzido pelo vento. Os resultados obtidos através do modelo demonstraram ser bastante consistentes com as observações e com as Imagens de Satélite, pelo que este modelo numérico reproduz realisticamente os resultados. ABSTRACT: The present work, as a dissertation of the Master’s Degree Programme in Meteorology and Physical Oceanography at the University of Aveiro, is associated with a survey (NeoMav), conducted by the IPIMAR, with two Investigation boats, Noruega and Tellina, in July of 2007. An analysis of the data provided by the CTDF is made in order to characterize temperature, salinity, density and chlorophyll-a concentration, in the region near the cost of Aveiro, in the western Iberian region. The information of the both cruises was complemented with: a fine resolution model ROMS-AGRIF, with 900 m of resolution approximately, forced in realistic conditions; ii) data from satellite imagery of surface temperature (series NOAA, sensor AVHRR) and chlorophyll-a concentration (sensor MODIS, Satellite Terra). The responses of middle and inner shelves are studied due to the forcing of the atmospheric conditions, during the alternation between Southward winds and relaxation, in the summer, in the region of the study. The most striking features are: the upwelled water during the upwelling; the appearance of a Northward counter current during the relaxation; the appearance of a front, which separates cold upwelled waters from warmer oceanic water; the signature of less salinity lens from Douro river, with a plume going Southward, associated to the flow, and offshore, associated to the Ekman transport induced by the wind. There is plenty of agreement between the results from the numeric model, the observations and the satellite imagery

Tomografia passiva costiera (TOMPACO). Inversion results with passive data - phase 3

Rep 02/03 - SiPLAB 28/March/2003This report shows the acoustic inversion results obtained on the INTIFANTE’00 data set, Events II, IV, V and VI

Real-time environmental inversion using a network of light receiving systems

This paper reports preliminary environmental inversion results of acoustic data collected simultaneously at two receiving systems during the RADAR’07 sea trial. These receiving systems have communication capabilities that allow for transfering acoustic and telemetric data to a base station with processing capabilities in order to produce environmental estimates during the acoustic experiment. During a large part of the experiment estimates on the temperature field appear to agree with concurrent ground truth data

Matched-field tomography using an acoustic oceanographic buoy

The Acoustic Oceanographic Buoy (AOB) is a light acoustic receiving device that is being developed in the framework of a joint research project and tested during the Maritime Rapid Environmental Assessment (MREA) sea trials. One of the AOB’s application is in Matched-Field Tomography (MFT) when a reduced number of receivers is available in opposition to traditional systems used in tomography. One problem of chief importance in MFT is the degree of uniqueness of the problem’s solution which is highly dependent on the number of receivers and on the number of free parameters. This paper studies the possibility of using matched-field processors with reduced ambiguity levels in comparison to conventional processors with application to acoustic data collected during the MREA sea trials. Two aspects are investigated: (a) the choice of an explicit broadband data model, where the exploitation of the spectral coherence of the acoustic field is seen as a mean to reduce the ambiguity level of the cost function used in the optimization; (b) conventional and high-resolution methods based on the proposed broadband model are implemented and compared.FC

Broadband MFP: coherent vs. incoherent

Matched-Field Processing (MFP) is now a mature technique for source localization and tracking. There are at least two aspects that emerge, by their relevance, to the success of MFP: one is the ability of a given MFP processor to accurately pinpoint the source location while rejecting sidelobes, and the other is the impact of erroneous or missing environmental information (known as model mismatch) in the final source location estimate. This study addresses the first aspect regarding sidelobe rejection while considering that the processor is working on a mismatch free situation. One well known procedure to reduce sidelobes is to use a broadband MFP processor (whenever a band of frequencies is available). There are a number of different ways to combine MFP information across frequency that ran be classified in two broad groups: the conventional incoherent methods, that are based on the direct averaging of the auto-frequency inner products and the, say, less conventional methods, that perform a weighted average of the cross-frequency inner products where the weights are the frequency compensation phase-shifts. The later are generally termed as coherent broadband methods since they combine complex inner products. The coherent broadband methods proposed in the literature are either suboptimal or very computationally Intensive, even for a small number of frequencies. An alternative method is presented that combines cross-frequency information with the same localization performance than the standard coherent methods and a computation load similar to that of the incoherent processor. The performance of the various broadband processors is compared in simulated data

Avaliação termográfica dos efeitos da aplicação de Kinesio Taping no músculo trapézio superior durante a execução de uma tarefa de mobilização passiva

Projeto de Graduação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Licenciado em FisioterapiaObjetivo: Avaliar os efeitos de uma aplicação de kinesio taping (KT) na temperatura da pele do músculo trapézio superior, durante a execução de uma tarefa de mobilização passiva fisiológica da articulação coxofemoral para hiperextensão. Metodologia: 15 indivíduos, com média de idades de 25,53±5,45 anos, foram submetidos a avaliação termográfica, antes, depois e 5 minutos após uma tarefa de mobilização passiva. Cada participante foi avaliado em 3 dias consecutivos. Resultados: A tarefa de mobilização passiva provocou alterações estatisticamente significativas (p<0,05) na temperatura da pele, mas não se registaram diferenças estatisticamente significativas relativamente à aplicação de KT. Conclusão: Os resultados obtidos não permitem demonstrar alterações da temperatura da pele decorrentes da aplicação de KT no trapézio superior.Objective: To evaluate the effects of application of kinesio taping (KT) in skin temperature of the upper trapezius muscle during a physiological task of passive mobilization of the hip joint hyperextension. Methods: 15 subjects with a mean age of 25,53 ± 5,45 years, underwent thermographic evaluation, before, after and 5 minutes after a task passive mobilization. Each participant was assessed on 3 consecutive days. Results: The task of passive mobilization resulted in statistically significant changes (p<0,05) in skin temperature but there were no statistically significant changes caused by application of KT. Conclusion: The results do not prove changes in skin temperature resulting from the application of KT in the upper trapezius

Range-dependent acoustic tomography: modeling an upwelling filament using an asymmetric Gaussian function

SiPLAB Report 05/03, University of Algarve,2003.Acoustic tomography in range-dependent waveguides using source-array pair represents an inverse problem with many potential solutions. The present problem is to model an upwelling filament which is a localized up rise of cold water and introducing a high degree pf range dependence. In this study a parameterization scheme with a reduced number of parameters is proposed in order to represent the spatial evolution of the filament using an asymmetric Gaussian function parameterized by two variances, an amplitude coefficient and a mean value. Using a real data example of the filament of the California current system, this modelling scheme is tested on semi-synthetic data. The results indicate that such an approach can be considered for an efficient modelling of a complex oceanographic feature.FC

Development of a small robot prototype for educational purposes

The project consisted of simulating an Automated Guided Vehicles (AGV) system and creating a model of an AGV that will serve as a teaching kit for future generations. The simulation was performed in SIMTWO, a realistic robotics simulator. Three simulations were built of increasing complexity starting from the simple line movements to AGV systems. It was plotted in each simulation the most important graphs to present the reader and explain what has happened. Moreover CAD files were created of the AGV using 3D printing and assembled. Then, a software that runs on the Arduino, was developed, and it uses a six-byte combination of symbols and numbers to control the AGV.O projecto consistiu na simulação de um sistema de Automated Guided Vehicles (AGV) e na criação de um modelo de AGV que servirá como kit de ensino para as gerações futuras. A simulação foi feita em SIMTWO, um simulador robótico no mesmo, foram feitas três simulações de complexidade crescente a partir dos simples movimentos de linha para sistemas AGV. Foi traçado em cada simulação os gráficos mais importantes para apresentar o leitor e explicar o que aconteceu. Além disso, foram criados ficheiros CAD para o modelo AGV e criados utilizando a impressão e montagem 3D. Estes, um programa que corre no Arduino, foi concebido, e utiliza uma combinação de seis bytes de símbolos e números para controlar o AGV

The effects of international trade on economic growth: an empirical comparison between Portugal and the Netherlands

According to growth theory, trade flows are an important determinant of a country growth rate since they allow technological progress, which is a crucial factor in productivity and competiveness gains, fostering both economic performance and growth. The main goal of this Dissertation is to study the impact that international trade had on the economic growth of Portugal and the Netherlands in the period 1970-2010. Although both economies are small open economies the result registered is distinct. For Portugal both exports and imports play a significant role, as for the Netherlands only exports show a positive effect on GDP.De acordo com a teoria do crescimento económico o comércio internacional desempenha um papel determinante na taxa de crescimento económico de cada país, porque permite a difusão de progresso tecnológico levando a ganhos de produtividade e competitividade, que por sua vez promovem tanto o desempenho económico como o crescimento económico. O propósito desta Dissertação é estudar o impacto do comércio internacional de Portugal e da Holanda sobre o seu crescimento económico entre 1970 e 2010. Apesar de ambas economias serem pequenas economias abertas o resultado obtido é diferente. Para Portugal tanto as exportações como as importações têm um papel crucial, já no caso da Holanda apenas as exportações mostram um impacto positivo sobre o PIB