769 resultados para Normalization


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Statistical approaches to study extreme events require, by definition, long time series of data. In many scientific disciplines, these series are often subject to variations at different temporal scales that affect the frequency and intensity of their extremes. Therefore, the assumption of stationarity is violated and alternative methods to conventional stationary extreme value analysis (EVA) must be adopted. Using the example of environmental variables subject to climate change, in this study we introduce the transformed-stationary (TS) methodology for non-stationary EVA. This approach consists of (i) transforming a non-stationary time series into a stationary one, to which the stationary EVA theory can be applied, and (ii) reverse transforming the result into a non-stationary extreme value distribution. As a transformation, we propose and discuss a simple time-varying normalization of the signal and show that it enables a comprehensive formulation of non-stationary generalized extreme value (GEV) and generalized Pareto distribution (GPD) models with a constant shape parameter. A validation of the methodology is carried out on time series of significant wave height, residual water level, and river discharge, which show varying degrees of long-term and seasonal variability. The results from the proposed approach are comparable with the results from (a) a stationary EVA on quasi-stationary slices of non-stationary series and (b) the established method for non-stationary EVA. However, the proposed technique comes with advantages in both cases. For example, in contrast to (a), the proposed technique uses the whole time horizon of the series for the estimation of the extremes, allowing for a more accurate estimation of large return levels. Furthermore, with respect to (b), it decouples the detection of non-stationary patterns from the fitting of the extreme value distribution. As a result, the steps of the analysis are simplified and intermediate diagnostics are possible. In particular, the transformation can be carried out by means of simple statistical techniques such as low-pass filters based on the running mean and the standard deviation, and the fitting procedure is a stationary one with a few degrees of freedom and is easy to implement and control. An open-source MAT-LAB toolbox has been developed to cover this methodology, which is available at https://github.com/menta78/tsEva/(Mentaschi et al., 2016).

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Three approaches were applied to evaluate metal contamination in 41 sediment samples from the Santos - São Vicente Estuarine System: normalization to Al, statistical analysis and sediment quality guidelines (SQGs). The results showed increases in the concentrations of Zn, Ni, Pb, Cd, Cr and Hg, which seemed to be associated with human activities. The levels of Al, Fe and Co probably were associated with crustal material or natural weathering processes. About 45% of the samples presented concentrations exceeding TEL-ERL, levels occasionally associated with adverse biological effects. Four of these samples presented concentrations above PEL-ERM, levels frequently associated with adverse biological effects.

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Inter-subject parcellation of functional Magnetic Resonance Imaging (fMRI) data based on a standard General Linear Model (GLM) and spectral clustering was recently proposed as a means to alleviate the issues associated with spatial normalization in fMRI. However, for all its appeal, a GLM-based parcellation approach introduces its own biases, in the form of a priori knowledge about the shape of Hemodynamic Response Function (HRF) and task-related signal changes, or about the subject behaviour during the task. In this paper, we introduce a data-driven version of the spectral clustering parcellation, based on Independent Component Analysis (ICA) and Partial Least Squares (PLS) instead of the GLM. First, a number of independent components are automatically selected. Seed voxels are then obtained from the associated ICA maps and we compute the PLS latent variables between the fMRI signal of the seed voxels (which covers regional variations of the HRF) and the principal components of the signal across all voxels. Finally, we parcellate all subjects data with a spectral clustering of the PLS latent variables. We present results of the application of the proposed method on both single-subject and multi-subject fMRI datasets. Preliminary experimental results, evaluated with intra-parcel variance of GLM t-values and PLS derived t-values, indicate that this data-driven approach offers improvement in terms of parcellation accuracy over GLM based techniques.

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O emprego das Forças Armadas Portuguesas em Operações Conjuntas e Combinadas faz-se no âmbito do quadro de alianças de que Portugal faz parte, das quais destacamos a Organização do Tratado do Atlântico Norte. No sentido de melhorar a eficácia operacional, a normalização assume um papel fundamental para que se possa atingir a interoperabilidade entre as forças da Aliança. Assim, este trabalho teve como objetivo principal, analisar e sintetizar os processos de normalização e desenvolvimento de doutrina Militar Conjunta e Combinada nas Forças Armadas Portuguesas. Tem ainda como finalidade, identificar lacunas nos processos nacionais, de forma a contribuir para uma melhor integração e harmonização da doutrina da Aliança, tendo em consideração a doutrina nacional e os interesses nacionais. A nossa investigação baseou-se num raciocínio hipotético-dedutivo, apoiado por uma estratégia qualitativa. O modelo de análise desenvolvido teve por hipóteses, que foram deduzidas de questões derivadas da questão central. Neste processo analítico, identificámos indicadores que permitiram a validação das hipóteses, para este efeito, recorremos a dois estudos de caso e uma análise SWOT. O desenvolvimento de um plano de ação que permita a integração dos processos analisados constitui o principal contributo desta investigação. A necessidade de criar uma Estrutura Coordenadora de Normalização, primordial para agilizar os procedimentos de normalização entre o Ministério da Defesa Nacional, o Estado-Maior General das Forças Armadas e os Ramos, juntamente, com a criação de um Conselho Superior de Doutrina nas Forças Armadas, que defina as prioridades e orientações gerais para o desenvolvimento de doutrina, constituem os principais resultados desta investigação. Abstract: The use of the Portuguese Armed Forces in Combined and Joint Operations is made within the framework of alliances that Portugal is a member, of which we highlight the North Atlantic Treaty Organization. In order to improve the operational efficiency, standardization plays a key role in achieving the interoperability between the forces of the Alliance. The aim of this study is to analyse and synthesize the standardization and development processes of Combined and Joint Military Doctrine in the Portuguese Armed Forces. Identify gaps in national processes, in order to contribute to a better integration and harmonization of the Alliance Doctrine, taking into account the national doctrine and national interests. Our research was based on a hypothetical-deductive argument, supported by a qualitative strategy. The analysis model developed based on assumptions, deducted from derivatives questions of the central question. In this analytical process, we identify indicators that allowed the validation of hypotheses, to achieve this purpose we used two case studies and resort to a SWOT analysis. The development of an action plan that allows the integration of the analysed processes is the main contribution of this research. The need to create a Standardization Coordination Structure it´s crucial to streamline the procedures of normalization between the Ministry of Defence, the Armed Forces General Joint Staff and the Services, along with the establishment of a Doctrine Supreme Council in the Armed Forces, which set the priorities and guidelines for the development of doctrine. This are the main outputs of this research.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade Gama, Programa de Pós-Graduação em Engenharia Biomédica, 2015.

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É hoje consensual, entre as várias correntes da gestão, que a obtenção de vantagens competitivas depende em grande medida das estratégias de gestão de recursos humanos. Orientada para os aspectos estratégicos, a gestão por competências surge como uma abordagem capaz de integrar os objectivos das organizações com os objectivos individuais. Simultaneamente, as novas tendências da gestão pública apontam para a necessidade de desenvolver processos conducentes à melhoria contínua dos serviços prestados, introduzindo um maior rigor na informação de gestão. São princípios subjacentes a estas novas tendências a necessidade de redução de custos, o aumento da produtividade, a normalização de processos e sistemas e o desenvolvimento de centros de competência e inovação. Neste trabalho, de natureza essencialmente empírica, pretendemos ilustrar o processo de concepção e implementação de um Programa de Avaliação e Desenvolvimento de Competências que foi desenvolvido para uma Unidade de Serviços Partilhados, no âmbito de uma organização pública. ABSTRACT: lt is actually consensual between several theoretical approaches that the attainment of competitive advantages depends on strategies of human resource management. Guided for strategic aspects, competencies’ management appears as an approach capable of integrating organizations and individual's goals. Simultaneously, the new trends of public administration point out the necessity of developing continuous improvement processes, introducing a higher quality in the management information. The necessity of costs reduction, the increase of the productivity and the normalization of processes and systems, as well the development of competencies centers and innovation, are underlying principles to these new trends. ln this empirical work we intend to illustrate the process of conception and implementation of a Program of Evaluation and Development of Competencies, developed for a Unit of Shared Services, in a public organization.

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Background: Hereditary Tyrosinemia type I (HTI) is a metabolic disease caused by deficiency of fumarylacetoacetate hydrolase enzyme. Objectives: This study reports beside its clinical and biochemical presentation, the outcome of NTBC [2- (2-nitro-4-trifloro-methylbenzoyl)-1, 3-cyclohexanedion] treatment of the disease and evaluates its biochemical markers in 16 pediatric Libyan patients. Patients and Methods: The diagnosis was based on presence of high tyrosine levels in blood and succinylacetone in urine. Results: The consanguinity rate was 81.2%, the median age at onset, at diagnosis and at starting treatment were 4.5, 8, and 9.5 months respectively. At presentation hepatomegaly, jaundice, rickets and high gamma glutamyl transferase (GGT) were observed in 87.5% of patients. All patients had extremely high alpha fetoprotein (AFP) and high alkaline phosphatase (ALP) levels. Fifteen patients were treated with NTBC, normalization of PT (Prothrombine time) was achieved in average in 14 days. The other biochemical parameters of liver function (transaminases, GGT, ALP, bilirubin and albumin) took longer to improve and several months to be normalized. Survival rate with NTBC was 86.6%. Patients who started treatment in a median of 3 months post onset observed a fast drop of AFP in 90.6% of patients (P = 0.003). Abnormal liver function and rickets were the common presentations, GGT was an early cholestatic sensitive test. ALP was constantly high even in asymptomatic patients. Conclusions: In HT1 a faster dropping of AFP is a marker of good prognosis.

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La rédaction de ce mémoire a été possible grâce à la bourse d’études supérieures du Canada (BESC M), Joseph-Armand-Bombardier du Centre de Recherche en Sciences Humaines (CRSH) du gouvernement du Canada, 2015.

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La rédaction de ce mémoire a été possible grâce à la bourse d’études supérieures du Canada (BESC M), Joseph-Armand-Bombardier du Centre de Recherche en Sciences Humaines (CRSH) du gouvernement du Canada, 2015.

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Ribosome profiling (Ribo-seq), a promising technology for exploring ribosome decoding rates, is characterized by the presence of infrequent high peaks in ribosome footprint density and by long alignment gaps. Here, to reduce the impact of data heterogeneity we introduce a simple normalization method, Ribo-seq Unit Step Transformation (RUST). RUST is robust and outperforms other normalization techniques in the presence of heterogeneous noise. We illustrate how RUST can be used for identifying mRNA sequence features that affect ribosome footprint densities globally. We show that a few parameters extracted with RUST are sufficient for predicting experimental densities with high accuracy. Importantly the application of RUST to 30 publicly available Ribo-seq data sets revealed a substantial variation in sequence determinants of ribosome footprint frequencies, questioning the reliability of Ribo-seq as an accurate representation of local ribosome densities without prior quality control. This emphasizes our incomplete understanding of how protocol parameters affect ribosome footprint densities.

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Estudios afirman que la acidez gástrica es importante en la absorción de levotiroxina (LT4) con resultados controversiales sobre la interacción entre inhibidores de bomba de protones (IBP) y LT4. El objetivo del estudio fue establecer el efecto del uso concomitante de LT4 e IBP en los niveles de TSH en pacientes adultos con hipotiroidismo primario. Se realizó una revisión sistemática mediante búsqueda en Medline, Embase, Lilacs, Bireme, Scielo, Cochrane y Universidad de York, Access Pharmacy, Google Scholar, Dialnet y Opengray. La búsqueda no se limito por lenguaje. Se evaluó el efecto en la diferencia de medias de TSH luego del consumo de LT4 y luego del consumo concomitante con IBP. Se hizo un metaanálisis, análisis de subgrupos y análisis de sensibilidad utilizando el programa Review Manager 5.3. Se eligieron 5 artículos para el análisis cualitativo y 3 para el metaanálisis. La calidad de los estudios fue buena y el riesgo de sesgos bajo. La diferencia de medias obtenida fue 0.21 mUI/L (IC95%: 0.02-0.40; p=0.03; I2:0%). En el análisis de subgrupos en pacientes mayores de 55 años la diferencia de medias fue 0.21 mUI/L (IC95%: 0.01-0.40; p=0.27; I2:19%). En el análisis de sensibilidad se excluyo el estudio con mayor muestra y la diferencia de medias fue 0.49 mUI/L (IC95%: -0.12 a 1.11; p=0.12; I2:0%). La diferencia de medias de TSH luego del consumo concomitante no se considera clínicamente significativa pues no representa riesgo para el paciente. Son necesarios estudios clínicos aleatorizados y evaluar el efecto en los niveles de T4 libre.

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El presente estudio de caso tiene como objetivo analizar la influencia de la gobernación de Tokio en la formulación de la política exterior de Japón durante la disputa territorial por las islas Senkaku/Diaoyu. Para ello, se identifican los puntos más relevantes de la política exterior de seguridad de Japón después de la Segunda Guerra Mundial. Se hace un énfasis en la política bilateral de seguridad sino-japonesa, con el fin de ubicar el conflicto territorial por las islas Senkaku/Diaoyu como un punto importante en la agenda internacional de seguridad de ambos países. Se estudia y analiza el concepto de paradiplomacia; articulado, a su vez, por los conceptos de identidad y rol en política exterior de la perspectiva teórica del Constructivismo de las Relaciones Internacionales, para así analizar la influencia de Tokio en el manejo de la política exterior de Japón en el marco del conflicto territorial por las islas Senkaku/Diaoyu.

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Stroke stands for one of the most frequent causes of death, without distinguishing age or genders. Despite representing an expressive mortality fig-ure, the disease also causes long-term disabilities with a huge recovery time, which goes in parallel with costs. However, stroke and health diseases may also be prevented considering illness evidence. Therefore, the present work will start with the development of a decision support system to assess stroke risk, centered on a formal framework based on Logic Programming for knowledge rep-resentation and reasoning, complemented with a Case Based Reasoning (CBR) approach to computing. Indeed, and in order to target practically the CBR cycle, a normalization and an optimization phases were introduced, and clustering methods were used, then reducing the search space and enhancing the cases re-trieval one. On the other hand, and aiming at an improvement of the CBR theo-retical basis, the predicates` attributes were normalized to the interval 0…1, and the extensions of the predicates that match the universe of discourse were re-written, and set not only in terms of an evaluation of its Quality-of-Information (QoI), but also in terms of an assessment of a Degree-of-Confidence (DoC), a measure of one`s confidence that they fit into a given interval, taking into account their domains, i.e., each predicate attribute will be given in terms of a pair (QoI, DoC), a simple and elegant way to represent data or knowledge of the type incomplete, self-contradictory, or even unknown.

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O presente estudo apresenta as qualidades psicométricas do Questionário de Cooperação Organizacional (QCO). A amostra é constituída por 300 funcionários camarários, dos departamentos de Atendimento e Urbanismo, de 70 Câmaras Municipais de Portugal Continental. Recorreu-se a procedimentos de Análise Factorial Exploratória, método de Máxima Verosimilhança, Scree Test, com método de rotação Varimax with Kaiser Normalization. Os resultados demonstram que o QCO é capaz de medir 3 dimensões da cooperação organizacional, explicando 49,36% da variância total. Os valores de consistência interna foram bastante satisfatórios, com a dimensão 1 “Cooperação configurada por regulamentações formais" a apresentar um Alpha de Cronbach de 0,875, a dimensão 2, "Cooperação decorrente da interdependência de indivíduos únicos articulados entre si" com 0,864 e a dimensão 3 "Cooperação através da orientação para a sociedade dos contributos singulares" com 0,787. /ABSTRACT: This study presents the analysis of psychometric properties of the Questionário de Cooperação Organizacional (QCO) (Organizational Cooperation Questionnaire). lt was applied to a sample of 300 employees from the Reception and Urbanization departments of 70 continental portuguese town-halls. Procedures of Exploratory Factorial Analysis, Maximum Likelihood extraction method and Varimax with Kaiser Normalization rotation method were performed. Results indicate that the QCO is capable of measuring 3 organizational cooperation dimensions, which explain 49,36% of the total variance. Reliability statistics were very satisfactory, in which dimension 1 "Cooperation structured by formal regulamentation" has a Cronbach's Alpha of 0,875, dimension 2, "The cooperation originated from the interdependence by the articulation amongst unique individuals" 0,864, and dimension 3 "Orientation to society of singular contribution through cooperation" 0,787.

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As descrições de produtos turísticos na área da hotelaria, aviação, rent-a-car e pacotes de férias baseiam-se sobretudo em descrições textuais em língua natural muito heterogénea com estilos, apresentações e conteúdos muito diferentes entre si. Uma vez que o sector do turismo é bastante dinâmico e que os seus produtos e ofertas estão constantemente em alteração, o tratamento manual de normalização de toda essa informação não é possível. Neste trabalho construiu-se um protótipo que permite a classificação e extracção automática de informação a partir de descrições de produtos de turismo. Inicialmente a informação é classificada quanto ao tipo. Seguidamente são extraídos os elementos relevantes de cada tipo e gerados objectos facilmente computáveis. Sobre os objectos extraídos, o protótipo com recurso a modelos de textos e imagens gera automaticamente descrições normalizadas e orientadas a um determinado mercado. Esta versatilidade permite um novo conjunto de serviços na promoção e venda dos produtos que seria impossível implementar com a informação original. Este protótipo, embora possa ser aplicado a outros domínios, foi avaliado na normalização da descrição de hotéis. As frases descritivas do hotel são classificadas consoante o seu tipo (Local, Serviços e/ou Equipamento) através de um algoritmo de aprendizagem automática que obtém valores médios de cobertura de 96% e precisão de 72%. A cobertura foi considerada a medida mais importante uma vez que a sua maximização permite que não se percam frases para processamentos posteriores. Este trabalho permitiu também a construção e população de uma base de dados de hotéis que possibilita a pesquisa de hotéis pelas suas características. Esta funcionalidade não seria possível utilizando os conteúdos originais. ABSTRACT: The description of tourism products, like hotel, aviation, rent-a-car and holiday packages, is strongly supported on natural language expressions. Due to the extent of tourism offers and considering the high dynamics in the tourism sector, manual data management is not a reliable or scalable solution. Offer descriptions - in the order of thousands - are structured in different ways, possibly comprising different languages, complementing and/or overlap one another. This work aims at creating a prototype for the automatic classification and extraction of relevant knowledge from tourism-related text expressions. Captured knowledge is represented in a normalized/standard format to enable new services based on this information in order to promote and sale tourism products that would be impossible to implement with the raw information. Although it could be applied to other areas, this prototype was evaluated in the normalization of hotel descriptions. Hotels descriptive sentences are classified according their type (Location, Services and/or Equipment) using a machine learning algorithm. The built setting obtained an average recall of 96% and precision of 72%. Recall considered the most important measure of performance since its maximization allows that sentences were not lost in further processes. As a side product a database of hotels was built and populated with search facilities on its characteristics. This ability would not be possible using the original contents.