986 resultados para Digital services
Resumo:
Plain radiography still accounts for the vast majority of imaging studies that are performed at multiple clinical instances. Digital detectors are now prominent in many imaging facilities and they are the main driving force towards filmless environments. There has been a working paradigm shift due to the functional separation of acquisition, visualization, and storage with deep impact in the imaging workflows. Moreover with direct digital detectors images are made available almost immediately. Digital radiology is now completely integrated in Picture Archiving and Communication System (PACS) environments governed by the Digital Imaging and Communications in Medicine (DICOM) standard. In this chapter a brief overview of PACS architectures and components is presented together with a necessarily brief account of the DICOM standard. Special focus is given to the DICOM digital radiology objects and how specific attributes may now be used to improve and increase the metadata repository associated with image data. Regular scrutiny of the metadata repository may serve as a valuable tool for improved, cost-effective, and multidimensional quality control procedures.
Resumo:
In order to develop a flexible simulator, a variety of models for Ancillary Services (AS) negotiation has been implemented in MASCEM – a multi-agent system competitive electricity markets simulator. In some of these models, the energy and the AS are addressed simultaneously while in other models they are addressed separately. This paper presents an energy and ancillary services joint market simulation. This paper proposes a deterministic approach for solving the energy and ancillary services joint market. A case study based on the dispatch of Regulation Down, Regulation Up, Spinning Reserve, and Non-Spinning Reserve services is used to demonstrate that the use of the developed methodology is suitable for solving this kind of optimization problem. The presented case study is based on CAISO real AS market data considers fifteen bids.
Resumo:
Temos assistido, especialmente ao longo dos últimos dois anos,a um progressivo aumento da utilização das redes sociais por parte da Presidência da República Portuguesa, com destaque para o Facebook. Tal repete a tendência registada a nível mundial, com especial destaque para os EUA e para o seu actual presidente, Barack Obama. No caso português, a Presidência da República, órgão de soberania liderado pelo Prof. Cavaco Silva,é um dos mais activos nesta frente, procurando utilizar as redes sociais como um barómetro sobre a forma como os portugueses sentem a democracia e o estado da nação.
Resumo:
This paper proposes two meta-heuristics (Genetic Algorithm and Evolutionary Particle Swarm Optimization) for solving a 15 bid-based case of Ancillary Services Dispatch in an Electricity Market. A Linear Programming approach is also included for comparison purposes. A test case based on the dispatch of Regulation Down, Regulation Up, Spinning Reserve and Non-Spinning Reserve services is used to demonstrate that the use of meta-heuristics is suitable for solving this kind of optimization problem. Faster execution times and lower computational resources requirements are the most relevant advantages of the used meta-heuristics when compared with the Linear Programming approach.
Resumo:
Adequate decision support tools are required by electricity market players operating in a liberalized environment, allowing them to consider all the business opportunities and take strategic decisions. Ancillary services (AS) represent a good negotiation opportunity that must be considered by market players. Based on the ancillary services forecasting, market participants can use strategic bidding for day-ahead ancillary services markets. For this reason, ancillary services market simulation is being included in MASCEM, a multi-agent based electricity market simulator that can be used by market players to test and enhance their bidding strategies. The paper presents the methodology used to undertake ancillary services forecasting, based on an Artificial Neural Network (ANN) approach. ANNs are used to day-ahead prediction of non-spinning reserve (NS), regulation-up (RU), and regulation down (RD). Spinning reserve (SR) is mentioned as past work for comparative analysis. A case study based on California ISO (CAISO) data is included; the forecasted results are presented and compared with CAISO published forecast.
Resumo:
Electricity market players operating in a liberalized environment requires access to an adequate decision support tool, allowing them to consider all the business opportunities and take strategic decisions. Ancillary services represent a good negotiation opportunity that must be considered by market players. For this, decision support tool must include ancillary market simulation. This paper proposes two different methods (Linear Programming and Genetic Algorithm approaches) for ancillary services dispatch. The methodologies are implemented in MASCEM, a multi-agent based electricity market simulator. A test case based on California Independent System Operator (CAISO) data concerning the dispatch of Regulation Down, Regulation Up, Spinning Reserve and Non-Spinning Reserve services is included in this paper.
Resumo:
Electricity market players operating in a liberalized environment requires access to an adequate decision support tool, allowing them to consider all the business opportunities and take strategic decisions. Ancillary services represent a good negotiation opportunity that must be considered by market players. For this, decision support tools must include ancillary market simulation. This paper proposes two different methods (Linear Programming and Genetic Algorithm approaches) for ancillary services dispatch. The methodologies are implemented in MASCEM, a multi-agent based electricity market simulator. A test case concerning the dispatch of Regulation Down, Regulation Up, Spinning Reserve and Non-Spinning Reserve services is included in this paper.
Resumo:
Will the existing means in Radiotherapy respond to the needs of the potential user population in 2014 for Lisbon and Santarém districts? Number of treatment units? Number of Radiotherapy Technologists? Temporal variations of the dimension and age structure of the populations: Coastal areas/Interior areas, Urban areas/Rural areas. Temporal variations in the incidence of several types of cancer. Overall objectives: evaluate of the necessities of Radiotherapy for Lisbon and Santarém districts in 2014 and elaboration of proposals that aim the access/use for the potential user population.
Resumo:
Introdução: O uso das TIC, nomeadamente dos ambientes virtuais de aprendizagem, são uma possibilidade pedagógica promissora e atractiva pois permitem a construção de conhecimento e a interacção entre alunos, professores e tutores. Na perspectiva do estudante, compreende-se que, em contextos virtuais de aprendizagem a tendência é a de se valorizar cada vez mais a sua participação no processo de ensino e de aprendizagem. No entanto, para que seja possível a implementação de educação a distância é necessário que os estudantes, para além da motivação e da responsabilidade acrescida, possuam um conjunto de competências específicas para participar, efectivamente, num contexto virtual de aprendizagem. Nesse contexto, e para verificar se o uso das tecnologias no processo educacional é exequível, é necessário conhecer as competências digitais dos alunos da Licenciatura em Farmácia da Escola Superior de Tecnologia da Saúde do Porto. Métodos: O estudo é descritivo-transversal e permitiu a recolha de dados através do inquérito por questionário, previamente validado. A amostra em estudo foi retirada da população formada pelos 230 estudantes da Licenciatura de Farmácia, por um processo de amostragem não probabilística por conveniência, perfazendo um total de 52 indivíduos que frequentam o 2º ano. Apresentação de Resultados e Discussão: Os resultados permitiram concluir que os estudantes utilizam as TIC de forma variada mas normalmente em actividades de lazer. Em relação ao conhecimento e utilização das ferramentas da Web 2.0 concluí-se que, na generalidade, os estudantes não conhecem e não dominam a maioria das ferramentas da Web 2.0.Ou seja, os estudantes, mesmo com as suas habilidades e conhecimentos sobre tecnologia, principalmente em relação ao uso de computadores e da Internet, e conhecendo a importância destes recursos como simplificadores nos estudos, continuam a apresentar limitações, provavelmente devido a falta de informação ou a informações duvidosas provenientes de uma utilização incorrecta dos recursos. Estes resultados representam também um desafio, uma vez que caberá à Escola capacitar os estudantes na utilização de novas tecnologias, uma vez que, estas capacidades são cada vez mais solicitadas no mercado de trabalho, e serão primordiais para o sucesso do estudante numa formação a distância mediada por computador.
Resumo:
É consensualmente reconhecida na atualidade a relevância da leitura na sociedade, abrindo-se, de forma crescente, a uma multiplicidade de dimensões alimentadas pela comunicação em rede. No ensino superior, tais dimensões merecem particular atenção, não só pelos desafios lançados pelo seu caráter cada vez mais diversificado, como pelas possíveis consequências que daí podem advir para o futuro profissional dos estudantes. Assim, nesta comunicação temos como objetivo indagar a importância do livro na era digital enquanto possível suporte configurador de práticas de leitura literária de estudantes do ensino superior a frequentar um 1.º Ciclo de estudos de Bolonha. No que se refere à metodologia adotada, face aos objetivos do estudo, considerámos adequada uma abordagem de natureza qualitativa, tendo como referencial metodológico o estudo de caso. Os participantes foram 27 estudantes inscritos na unidade curricular de Iniciação à Leitura e à Escrita que integra o plano de estudos da licenciatura em Educação Básica, na Escola Superior de Educação de Viseu (3.º ano, 1.º semestre, ano letivo 2015-2016). Os instrumentos utilizados foram 27 reflexões escritas individuais realizadas no âmbito do trabalho autónomo dos estudantes. A técnica privilegiada foi a análise de conteúdo. Apesar dos amplos itinerários de leitura proporcionados pela era digital, conclui-se que os estudantes atribuem grande importância ao livro impresso enquanto potenciador da motivação para a leitura literária, relegando para segundo plano possíveis vantagens do livro em suporte digital. Embora a tecnologia seja omnipresente no seu quotidiano, é o livro que resguarda os lugares das memórias que se entretecem nos seus percursos de leitura.
Resumo:
Combined tunable WDM converters based on SiC multilayer photonic active filters are analyzed. The operation combines the properties of active long-pass and short-pass wavelength filter sections into a capacitive active band-pass filter. The sensor element is a multilayered heterostructure produced by PE-CVD. The configuration includes two stacked SiC p-i-n structures sandwiched between two transparent contacts. Transfer function characteristics are studied both theoretically and experimentally. Results show that optical bias activated photonic device combines the demultiplexing operation with the simultaneous photodetection and self amplification of an optical signal acting the device as an integrated photonic filter in the visible range. Depending on the wavelength of the external background and irradiation side, the device acts either as a short- or a long-pass band filter or as a band-stop filter. The output waveform presents a nonlinear amplitude-dependent response to the wavelengths of the input channels. A numerical simulation and two building-blocks active circuit is presented and gives insight into the physics of the device.
Resumo:
Video coding technologies have played a major role in the explosion of large market digital video applications and services. In this context, the very popular MPEG-x and H-26x video coding standards adopted a predictive coding paradigm, where complex encoders exploit the data redundancy and irrelevancy to 'control' much simpler decoders. This codec paradigm fits well applications and services such as digital television and video storage where the decoder complexity is critical, but does not match well the requirements of emerging applications such as visual sensor networks where the encoder complexity is more critical. The Slepian Wolf and Wyner-Ziv theorems brought the possibility to develop the so-called Wyner-Ziv video codecs, following a different coding paradigm where it is the task of the decoder, and not anymore of the encoder, to (fully or partly) exploit the video redundancy. Theoretically, Wyner-Ziv video coding does not incur in any compression performance penalty regarding the more traditional predictive coding paradigm (at least for certain conditions). In the context of Wyner-Ziv video codecs, the so-called side information, which is a decoder estimate of the original frame to code, plays a critical role in the overall compression performance. For this reason, much research effort has been invested in the past decade to develop increasingly more efficient side information creation methods. This paper has the main objective to review and evaluate the available side information methods after proposing a classification taxonomy to guide this review, allowing to achieve more solid conclusions and better identify the next relevant research challenges. After classifying the side information creation methods into four classes, notably guess, try, hint and learn, the review of the most important techniques in each class and the evaluation of some of them leads to the important conclusion that the side information creation methods provide better rate-distortion (RD) performance depending on the amount of temporal correlation in each video sequence. It became also clear that the best available Wyner-Ziv video coding solutions are almost systematically based on the learn approach. The best solutions are already able to systematically outperform the H.264/AVC Intra, and also the H.264/AVC zero-motion standard solutions for specific types of content. (C) 2013 Elsevier B.V. All rights reserved.
Resumo:
Mestrado em Relações Internacionais.
Resumo:
OBJECTIVE: To evaluate knowledge, attitude and practice related to mammography among women users of local health services, identifying barriers to its performance. METHODS: A total of 663 women were interviewed at 13 local health centers in a city of Southeastern Brazil, in 2001. Interviewees were randomly selected at each center and they were representative from different socioeconomic conditions. The number of interviewees at each center was proportional to monthly mean appointments. For data analysis, answers were described as knowledge, attitude, practice and their respective adequacies and then they were correlated with control variables through the chi-square test. RESULTS: Only 7.4% of the interviewees had adequate knowledge on mammography, while 97.1% of women had an adequate attitude. The same was seen for the practice of mammography that was adequate in 35.7% of the cases. The main barrier to mammography was lack of referral by physicians working at the health center (81.8%). There was an association between adequacy of attitude and five years or more of education and being married. There was also an association between adequacy of mammography practice and being employed and family income up to four minimum wages. CONCLUSIONS: Women users of local health services had no adequate knowledge and practice related to mammography despite having an adequate attitude about this exam.
Resumo:
O movimento de afirmação eXtensible Business Reporting Language (XBRL), como padrão para a preparação e difusão dos relatórios financeiros e outras publicações empresariais, foi encabeçado pelo American lnstitute of Certified Public Accountants (AICPA) em conjunto com aproximadatnente outras 30 organizações. Desde o primeiro encontro internacional sobre a especificação XBRL, realizado em Nova York no mês de Outubro de 1999, que a lista de participantes se tem alargado incluindo proeminentes instituições financeiras, organizações profissionais de serviços, organizações profissionais de contabilidade e fornecedores de tecnologia sobrevindo, ao mesmo tempo, um incontável número de alianças e ligações. A XBRL é uma linguagem standard utilizada no ambiente da Internet cujo desenvolvimento permitirá obter uma informação de melhor qualidade, mais rápida, mais económica e mais eficaz, para o processo de criação e publicação de relatórios financeiros e empresariais. Neste artigo os autores apresentam, resumidamente, as vantagens referidas pela literatura para esta nova tecnologia, descrevem sumariamente as características técnicas da XBRL, traçam o seu percurso desde 1999 e analisam o potencial deste standard para Portugal, bem como a sua aplicação em diferentes áreas de investigação.