4,668 research outputs found

    Métodos geofísicos de exploração aplicados ao estudo da perigosidade sísmica

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    Nas últimas décadas os métodos geofísicos ganharam papel de relevo na avaliação da perigosidade do risco sísmico e na sua mitigação. A detecção de falhas activas em ambientes intra placa onde as taxas de movimentação são relativamente baixas (<0,3 mm/ano) e as roturas superficiais são obliteradas pela erosão e sedimentação, levaram à utlização daqueles métodos na investigação paleossismológica. A nível da mitigação, em que a avaliação dos efeitos de sítio é essencial, é necessário um conhecimento das propriedades mecânicas das primeiras dezenas de metros da sub-superfície e da estrutura das bacias sedimentares, que são obtidos a partir de sondagens geotécnicas e métodos geofísicos. A utilização dos métodos sísmicos, eléctricos e electromagnéticos na identificação de falhas e na estrutura do subsolo, a delimitação de bacias a partir de métodos potenciais e a caracterização das propriedades mecânicas do subsolo são analisadas no presente trabalho, com exemplos de aplicação em Portugal

    Economic crisis effects on SME dynamic capabilities

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    Based on dynamic capabilities theoretical framework, this research sought to understand the implications of the recent economic crisis on the capability of developing new products by Portuguese SMEs. Specifically, we assessed how this capability was affected by variables such as entrepreneurship, innovation capacity, the knowledge accumulation, and partnerships. The hypotheses were tested using two samples, one before the crisis, with 180 and another with 105 respondents, applied during the crisis (2012). Results reveal that during the crisis SMEs were more objective and effective in the use of their resources and capabilities. In particular, was found that during the crisis the entrepreneurship, innovation capacity, accumulation of knowledge and partnerships, have an impact on the capability of developing new products. Before the crisis, only entrepreneurship and knowledge accumulation have affected this capability.info:eu-repo/semantics/acceptedVersio

    Transport systems and mobility for smart cities

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    Nowadays, cities appear to be the best place to live, attracting more and more people and activities. However, not only does this movement represent a threat to the environment but also provides challenges and opportunities for everyone, e.g., people, companies, organizations, and governments. To provide a good urban quality of life, the efficiency of all assets, buildings, infrastructures, and all systems, as well as taking care of the natural environment, must be addressed and achieved. This paper will, therefore, present the available literature on the subject to discuss the present context, the main challenges, as well as the concept of smart cities, with future cities relying on the mobility and evolution of transport systems for smart, sustainable, resilient, and inclusive mobility. As a result of the research, it is possible to infer that an integrated smart mobility approach can support the efficiency of all transport networks for everyone, today and tomorrow, while faced with the threat of climate change and the challenges of citizens.(undefined

    Biomechanics of a pedestrian accident reconstruction

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    Pedestrians represent about 20% of the overall fatalities in Europe's road traffic accidents, as well as in Portugal. An in-depth investigation, accident reconstruction, is mandatory in order to analyze with care fundamental aspects of an accident. Detailed information about the injuries and injury causation mechanisms are with great use for it. Accident reconstruction computational techniques using pedestrian biomechanical models are used to evaluate the accident conditions that lead to major pedestrian injuries, such as the vehicle's speed and the impact location. For biomechanical injury criterions, the AIS (Abbreviated Injury Scale), the HIC (Head Injury Criterion) and some other injury criterions are used. Pedestrian's height, weight, gender, age, vehicle geometry (or category) and travelling speed, significantly influence the pedestrian injuries in the event of a road collision. The use of injury scales and biomechanical criterions in the in-depth accident investigation of road accidents, such as AIS, can improve significantly the quality of the reconstruction process. The computer simulation of vehicle-to-pedestrian collisions is fundamental for the study of the dynamics of these road accidents. Where did the pedestrian is when the vehicle hits him? Normally, there is no simple and clear answer. The pedestrian, if survives, states that he uses the crossway, the driver of the vehicle states otherwise, that the location of the pedestrian was much later than the pedestrian crossing. This work presents an accident where only the use of accident reconstruction specialized software, PC-Crash, conjugated with all available information allowed the determination of the vehicle's speed and the Location of the pedestrian.info:eu-repo/semantics/publishedVersio

    Aromatherapy in the control of stress and anxiety

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    Background: Currently, complementary and alternative medicine emerge as important therapies in the prevention and treatment of various health problems. In view of this, the present study aims to evaluate the efficacy of essential oils in reducing stress and anxiety levels in aromatherapy users, at a clinic of Bragança, Portugal. Methods: A study was performed with 36 individuals divided in two distinct groups: “aroma group” and “control group”. Individuals of "aroma group" were treated with a mixture of essential oils of Lavandula angustifolia Mill and Matricaria recutita L. applied with Effleurage massage while the individuals of "control group" received only Effleurage massage. Stress and anxiety levels of all individuals participating in the study were evaluated before and after the treatment. Additionally, the chemical composition of the essential oils was evaluated by GC and GC-MS. Results: In the aromatherapy assay, the “aroma group” showed a significant decrease of 12% and 30%, in stress and anxiety levels, respectively, in the “control group” this decrease was lower (3.3% and 2.6% for stress and anxiety levels, respectively). Conclusion: In this study, aromatherapy was effective in stress and anxiety levels reduction and linalool, the major compound of the essential oil mixture, may be positively contributing for these effects.info:eu-repo/semantics/publishedVersio

    Aromatherapy: ancient solutions for recent problems

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    Background: Currently, complementary and alternative medicine emerge as strategy in the prevention and treatment of various health problems. The present study aims to evaluate the efficacy of aromatherapy with Lavandula angustifolia Mill and Matricaria recutita L. in reducing stress and anxiety levels. Methods: A study was performed with 36 individuals divided in two distinct groups: “aroma group” and “control group”. Individuals of "aroma group" were treated with a mixture of essential oils of Lavandula angustifolia Mill and Matricaria recutita L. applied with Effleurage massage while the individuals of "control group" received only Effleurage massage. Stress and anxiety levels of all individuals participating in the study were evaluated before and after the treatment. Additionally, the chemical composition of the essential oils was evaluated by GC and GC-MS. Results: In the aromatherapy assay, the “aroma group” showed a significant decrease of 12% and 30%, in stress and anxiety levels, respectively while lower decrease was observed in “control group” (3.3% and 2.6% for stress and anxiety levels, respectively). Conclusion: In this study, aromatherapy was effective in stress and anxiety levels reduction and linalool, the major compound of the essential oil mixture, may be positively contributing for these effects.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020). The authors gratefully acknowledge the financial support provided by Fundação para a Ciência e a Tecnologia (FCT) under UID/AMB/50017/2013, FEDER PT2020-Compete 2020. Authors are also grateful to Gabinete Terapêutico Telmo Teles, Unipessoal, Lda, Bragança, for the availability to perform the aromatherapy assay.info:eu-repo/semantics/publishedVersio

    A computational approach to forecasting and minimizing electricity costs in the short-term market for distributors in Brazil

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    In Brazil, the electric power distributors must buy electricity on auctions one, three and five years ahead. If there is inefficiency in the contracting of electric energy, the chamber of Commercialization of Electric Energy, which enables the commercialization, can apply penalties. Thus, this paper proposes a computational approach to forecasting electricity by the class of the consumer using a multi-layer perceptron artificial neural network with a backpropagation algorithm and a prediction using time series techniques through the Bayesian and Akaike selection criteria. The forecast of electricity consumption can serve as support in the purchase of electricity in auctions in the regulated contracting environment and in the process of settlement of differences and for energy management, customer service, and distributor billing. The results show that a multilayer network with a backpropagation algorithm is able to learn the behavior of the data that influences the electric energy consumed by consumption class and can be used to follow the evolution in the demand of each class of consumption and, consequently, to help distributors in the process of contracting of electricity, reduce losses like fines, and reduce the costs of the energy distributor

    Neotectonic activity on the Carcavai fault zone (Algarve, Portugal)

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    Studies performed on the Carcavai fault zone, Eastern Algarve, revealed several deformational features in Plio-Quaternary sediments with potential neotectonic implications. These features include fracturing (faults and joints) and clastic dikes, located along the Carcavai fault. Most of the fractures appear to be the expression of the fault activity affecting the Plio-Quaternary sediments. This is suggested by a consistent strike, subparallel to the major tectonic structure, and by the location pattern. Evidences of the fault activity were also identified in the Mesozoic and Paleozoic rocks, though the age of that deformation is poorly constrained. It consists in the presence of zones of intensely brecciated rock and of adjoining coarse sedimentary deposits probably related to the dismantling of a fault scarp. The acquired data point to a late hercynian structure, reactivated as a left-lateral strike-slip fault with a thrust component during the Plio-Quaternary
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