61 resultados para Non-traditional exports


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Earthquakes are associated with negative events, such as large number of casualties, destruction of buildings and infrastructures, or emergence of tsunamis. In this paper, we apply the Multidimensional Scaling (MDS) analysis to earthquake data. MDS is a set of techniques that produce spatial or geometric representations of complex objects, such that, objects perceived to be similar/distinct in some sense are placed nearby/distant on the MDS maps. The interpretation of the charts is based on the resulting clusters since MDS produces a different locus for each similarity measure. In this study, over three million seismic occurrences, covering the period from January 1, 1904 up to March 14, 2012 are analyzed. The events, characterized by their magnitude and spatiotemporal distributions, are divided into groups, either according to the Flinn–Engdahl seismic regions of Earth or using a rectangular grid based in latitude and longitude coordinates. Space-time and Space-frequency correlation indices are proposed to quantify the similarities among events. MDS has the advantage of avoiding sensitivity to the non-uniform spatial distribution of seismic data, resulting from poorly instrumented areas, and is well suited for accessing dynamics of complex systems. MDS maps are proven as an intuitive and useful visual representation of the complex relationships that are present among seismic events, which may not be perceived on traditional geographic maps. Therefore, MDS constitutes a valid alternative to classic visualization tools, for understanding the global behavior of earthquakes.

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Mestre em Engenharia Civil - Especialização em Estruturas

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A sustentabilidade energética do planeta é uma preocupação corrente e, neste sentido, a eficiência energética afigura-se como sendo essencial para a redução do consumo em todos os setores de atividade. No que diz respeito ao setor residencial, o indevido comportamento dos utilizadores aliado ao desconhecimento do consumo dos diversos aparelhos, são factores impeditivos para a redução do consumo energético. Uma ferramenta importante, neste sentido, é a monitorização de consumos nomeadamente a monitorização não intrusiva, que apresenta vantagens económicas relativamente à monitorização intrusiva, embora levante alguns desafios na desagregação de cargas. Abordou-se então, neste documento, a temática da monitorização não intrusiva onde se desenvolveu uma ferramenta de desagregação de cargas residenciais, sobretudo de aparelhos que apresentavam elevados consumos. Para isso, monitorizaram-se os consumos agregados de energia elétrica, água e gás de seis habitações do município de Vila Nova de Gaia. Através da incorporação dos vetores de água e gás, a acrescentar ao da energia elétrica, provou-se que a performance do algoritmo de desagregação de aparelhos poderá aumentar, no caso de aparelhos que utilizem simultaneamente energia elétrica e água ou energia elétrica e gás. A eficiência energética é também parte constituinte deste trabalho e, para tal, implementaram-se medidas de eficiência energética para uma das habitações em estudo, de forma a concluir as que exibiam maior potencial de poupança, assim como rápidos períodos de retorno de investimento. De um modo geral, os objetivos propostos foram alcançados e espera-se que num futuro próximo, a monitorização de consumos não intrusiva se apresente como uma solução de referência no que respeita à sustentabilidade energética do setor residencial.

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Este estudo tem como objetivos: (1) conhecer as práticas desenvolvidas numa organização do Ensino Superior Público Português; (2) conhecer a tipologia das práticas de GRH de cariz tradicional e de cariz estratégico; (3) perceber em que medida as práticas de GRH estão relacionadas com a área de qualificação dos responsáveis do departamento de RH; (4) averiguar o grau de satisfação que os trabalhadores sentem com as Práticas de Gestão de Recursos Humanos desenvolvidas e a sua relação com a área de qualificação dos responsáveis do departamento de RH. Foi utilizada uma metodologia mista, que possibilita ampliar a obtenção de resultados em abordagens investigativas, proporcionando ganhos relevantes para a pesquisa. É realizado um primeiro estudo exploratório, que utiliza uma metodologia mista quantitativa e qualitativa, com recurso a uma entrevista semiestruturada e inquérito realizados aos responsáveis de RH, e que tem como objetivos identificar e caracterizar as Práticas de GRH vigentes na Organização e, consequentemente, averiguar se se aproximam das designadas na literatura, assim como averiguar o grau de intervenção do DRH no desenvolvimento das PGRH e caraterizar o perfil do responsável de RH na Organização, averiguando se a área de formação de RH influencia as Práticas de GRH desenvolvidas. No segundo estudo, recorremos a uma metodologia quantitativa com recurso ao inquérito por questionário, aplicado aos trabalhadores que exercem funções a tempo integral, para averiguar o grau de satisfação dos trabalhadores em relação às Práticas de Gestão de Recursos Humanos. Na compilação dos dois estudos foi nosso objetivo obter respostas às questões que orientaram a nossa investigação. Na parte final da dissertação são discutidos os principais resultados obtidos e apresentadas as conclusões do estudo aqui levado a cabo. Os resultados sugerem que: 1) as PGRH existentes são essencialmente de cariz tradicional, em especial a gestão administrativa; 2) as PGRH predominantes são: o Planeamento de Recursos Humanos, a Análise e Descrição de Funções, o Recrutamento e Seleção, a Formação e Desenvolvimento, a Gestão Administrativa, a Comunicação e a Partilha de Informação, Ética e Deontologia e o Estatuto Disciplinar; 3) existe pouco recurso ao outsourcing para as PGRH; 4) o grau de intervenção DRH baseia-se em atividades de cariz mais administrativo; 5) as práticas tradicionais de RH são aquelas que requerem mais tempo ao DRH; 6) não existe relação entre o tipo de PGRH e a área de qualificação do responsável do DRH; 7) as PGRH são realizadas seguindo essencialmente as normas legais e regras rígidas da GRH na AP; 8) algumas PGRH não são entendidas em contexto da AP, como importantes pelos gestores, embora já sejam desenvolvidos alguns procedimentos dessas práticas; 9) a PGRH da formação e desenvolvimento não é corretamente desenvolvida e não dá cumprimento ao estipulado na lei; 10) a gestão de carreiras e o sistema de compensação e recompensas são entendidas como inexistentes, porque não existem promoções e progressões desde 2005; 11) a avaliação do desempenho é um sistema burocrático e ritualista com fins de promoção e compensação, sem efeitos práticos no momento atual, e que causa insatisfação e o sentimento de injustiça; 12) existem problemas de comunicação quanto a partilha e uniformização de procedimentos entre UO; 13) a satisfação dos trabalhadores é maior com as PGRH de tipo tradicional, nomeadamente na gestão administrativa, recrutamento e seleção, análise e descrição de funções, acolhimento, integração e socialização 14) a satisfação é menor na gestão de carreiras, no sistema de compensação e recompensas e na avaliação do desempenho; 15) quanto a relação entre o grau de satisfação e as características sócio demográficas e profissionais dos inquiridos, os casos com significância mostram que os trabalhadores com 10 ou mais anos de antiguidade tendem a sentir mais satisfação com as práticas em GRH; 16) existe mais satisfação dos trabalhadores das UO onde o responsável de DRH possui formação na área de RH.

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The increasing importance of the integration of distributed generation and demand response in the power systems operation and planning, namely at lower voltage levels of distribution networks and in the competitive environment of electricity markets, leads us to the concept of smart grids. In both traditional and smart grid operation, non-technical losses are a great economic concern, which can be addressed. In this context, the ELECON project addresses the use of demand response contributions to the identification of non-technical losses. The present paper proposes a methodology to be used by Virtual Power Players (VPPs), which are entities able to aggregate distributed small-size resources, aiming to define the best electricity tariffs for several, clusters of consumers. A case study based on real consumption data demonstrates the application of the proposed methodology.

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The non-technical loss is not a problem with trivial solution or regional character and its minimization represents the guarantee of investments in product quality and maintenance of power systems, introduced by a competitive environment after the period of privatization in the national scene. In this paper, we show how to improve the training phase of a neural network-based classifier using a recently proposed meta-heuristic technique called Charged System Search, which is based on the interactions between electrically charged particles. The experiments were carried out in the context of non-technical loss in power distribution systems in a dataset obtained from a Brazilian electrical power company, and have demonstrated the robustness of the proposed technique against with several others natureinspired optimization techniques for training neural networks. Thus, it is possible to improve some applications on Smart Grids.

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Demand response has gained increasing importance in the context of competitive electricity markets and smart grid environments. In addition to the importance that has been given to the development of business models for integrating demand response, several methods have been developed to evaluate the consumers’ performance after the participation in a demand response event. The present paper uses those performance evaluation methods, namely customer baseline load calculation methods, to determine the expected consumption in each period of the consumer historic data. In the cases in which there is a certain difference between the actual consumption and the estimated consumption, the consumer is identified as a potential cause of non-technical losses. A case study demonstrates the application of the proposed method to real consumption data.

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The electricity demand in Brazil has been growing. Some studies estimate that through 2035 the energy consumption (the power consumption) should increase 78%. Two distinct actions are necessary to meet this growth: the construction of new generating plants and to reduce electrical losses in the country. As the construction of power plants have a high price, coupled with the growth of (current) environmental concern, electric utilities are investing in reducing losses, both technical and non-technical. In this context, this paper aims to present an overview of nontechnical losses in Brazil and to raise a discussion on the reasons that contribute to energy fraud.

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The electric utilities have large revenue losses annually due to commercial losses, which are caused mainly by fraud on the part of consumers and faulty meters. Automatic detection of such losses where there is a complex problem, given the large number of consumers and the high cost of each inspection, not to mention the wear of the relationship between company and consumer. Given the above, this paper aims to briefly present some methodologies applied by utilities to identify consumer frauds.

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13th IEEE/IFIP International Conference on Embedded and Ubiquitous Computing (EUC 2015). 21 to 23, Oct, 2015, Session W1-A: Multiprocessing and Multicore Architectures. Porto, Portugal.

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A new method for the study and optimization of manu«ipulator trajectories is developed. The novel feature resides on the modeling formulation. Standard system desciptions are based on a set of differential equations which, in general, require laborious computations and may be difficult to analyze. Moreover, the derived algorithms are suited to "deterministic" tasks, such as those appearing in a repetitivework, and are not well adapted to a "random" operation that occurs in intelligent systems interacting with a non-structured and changing environment. These facts motivate the development of alternative models based on distinct concepts. The proposed embedding of statistics and Fourier trasnform gives a new perspective towards the calculation and optimization of the robot trajectories in manipulating tasks.

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Recent embedded processor architectures containing multiple heterogeneous cores and non-coherent caches renewed attention to the use of Software Transactional Memory (STM) as a building block for developing parallel applications. STM promises to ease concurrent and parallel software development, but relies on the possibility of abort conflicting transactions to maintain data consistency, which in turns affects the execution time of tasks carrying transactions. Because of this fact the timing behaviour of the task set may not be predictable, thus it is crucial to limit the execution time overheads resulting from aborts. In this paper we formalise a FIFO-based algorithm to order the sequence of commits of concurrent transactions. Then, we propose and evaluate two non-preemptive and one SRP-based fully-preemptive scheduling strategies, in order to avoid transaction starvation.

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The occurrence of seven pharmaceuticals and two metabolites belonging to non-steroidal anti-inflammatory drugs and analgesics therapeutic classes was studied in seawaters. A total of 101 samples covering fourteen beaches and five cities were evaluated in order to assess the spatial distribution of pharmaceuticals among north Portuguese coast. Seawaters were selected in order to embrace different bathing water quality (excellent, good and sufficient). Acetaminophen, ketoprofen and the metabolite hydroxyibuprofen were detected in all the seawater samples at maximum concentrations of 584, 89.7 and 287 ng L− 1, respectively. Carboxyibuprofen had the highest seawater concentration (1227 ng L− 1). The temporal distribution of the selected pharmaceuticals during the bathing season showed that, in general, higher concentrations were detected in August and September. The environmental risk posed by the pharmaceuticals detected in seawaters towards different trophic levels (fish, daphnids and algae) was also assessed. Only diclofenac showed hazard quotients above one for fish, representing a potential risk for aquatic organisms. These results were observed in seawaters classified as excellent bathing water. Additional data is needed in order to support the identification and prioritization of risks posed by pharmaceuticals in marine environment.

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An analytical methodology for the simultaneous determination of seven pharmaceuticals and two metabolites belonging to the non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics therapeutic groups was developed based on off-line solid-phase extraction and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (SPE–UHPLC–MS/MS). Extraction conditions were optimized taking into account parameters like sorbent material, sample volume and sample pH. Method detection limits (MDLs) ranging from 0.02 to 8.18 ng/L were obtained. This methodology was successfully applied to the determination of the selected pharmaceuticals in seawater samples of Atlantic Ocean in the Northern Portuguese coast. All the pharmaceuticals have been detected in the seawater samples, with pharmaceuticals like ibuprofen, acetaminophen, ketoprofen and the metabolite hydroxyibuprofen being the most frequently detected at concentrations that can reach some hundreds of ng/L.