969 resultados para implementation method


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This communications describes an electromagnetic model of a radial line planar antenna consisting of a radial guide with one central probe and many peripheral probes arranged in concentric circles feeding an array of antenna elements such as patches or wire curls. The model takes into account interactions between the coupling probes while assuming isolation of radiating elements. Based on this model, computer programs are developed to determine equivalent circuit parameters of the feed network and the radiation pattern of the radial line planar antenna. Comparisons are made between the present model and the two-probe model developed earlier by other researchers.

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The role of sunscreens in preventing skin cancer and melanoma is the focus of ongoing research. Currently, there is no objective measure which can be used in field studies to determine whether a person has applied sunscreen to their skin, and researchers must use indirect assessments such as questionnaires. We sought to develop a rapid, non-invasive method for identifying sunscreen on the skin for use in epidemiological studies. Our basic method is to swab the skin, elute any residues which have been adsorbed onto the swab by rinsing in ethanol, and submit the eluted washings for spectrophotometric analysis. In a controlled study, we applied 0.1 ml of sunscreen to a 50 cm(2) grid on both forearms of 21 volunteers. Each forearm was allocated one of 10 different sunscreen brands. The skin was swabbed after intervals of 20 min, 1 h, 2 h and 4 h. In a field study conducted among 12 children aged 2-4 years attending a child care centre, sunscreen was applied to the faces of half the children. Swabs were then taken from the face and back of all children without knowledge of sunscreen status. In the controlled study, sunscreen was clearly detectable up to 2 h after application for all brands containing organic sunscreen, and marginally detectable at 4 h. In the field study, this method correctly identified all children with and without sunscreen. We conclude that spectrophotometric analysis of skin swabs can reliably detect the presence of sunscreen on the skin for up to 2 It after application. (C) 2002 Elsevier Science B.V. All rights reserved.

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Frequency deviation is a common problem for power system signal processing. Many power system measurements are carried out in a fixed sampling rate assuming the system operates in its nominal frequency (50 or 60 Hz). However, the actual frequency may deviate from the normal value from time to time due to various reasons such as disturbances and subsequent system transients. Measurement of signals based on a fixed sampling rate may introduce errors under such situations. In order to achieve high precision signal measurement appropriate algorithms need to be employed to reduce the impact from frequency deviation in the power system data acquisition process. This paper proposes an advanced algorithm to enhance Fourier transform for power system signal processing. The algorithm is able to effectively correct frequency deviation under fixed sampling rate. Accurate measurement of power system signals is essential for the secure and reliable operation of power systems. The algorithm is readily applicable to such occasions where signal processing is affected by frequency deviation. Both mathematical proof and numerical simulation are given in this paper to illustrate robustness and effectiveness of the proposed algorithm. Crown Copyright (C) 2003 Published by Elsevier Science B.V. All rights reserved.

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This paper continues the development of a new approach for the design of shim and gradient coils, used in magnetic resonance imaging (MRI) applications. A cylindrical primary coil of radius a and length 2L is placed inside a co-axial shield cylinder of radius b. An active shielding strategy is used to create a desired target field at an arbitrarily specified (cylindrical) location within the primary coil, and to annul the field at a certain radius outside the shield. The form of the interior target field may be chosen arbitrarily by the designer, although zonal and tesseral harmonics are typically used in MRI applications. The method presented here designs coil windings on both the primary and shielding cylinders, to produce fields that conform to the specified interior target field and the annulled field exterior to the shield. An additional feature of the method presented here is that the target field inside the primary coil is matched at two different radii, to improve overall accuracy. The method is illustrated by designing several shielded shim coils, for creating higher order tesseral fields located asymmetrically within the coil. The simpler case of pure zonal fields is discussed separately and applied to the design of some higher order shielded coils.

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A Combined Genetic Algorithm and Method of Moments design methods is presented for the design of unusual near-field antennas for use in Magnetic Resonance Imaging systems. The method is successfully applied to the design of an asymmetric coil structure for use at 190MHz and demonstrates excellent radiofrequency field homogeneity.

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This study aimed to develop a practical method of estimating energy expenditure (EE) during tennis. Twenty-four elite female tennis players first completed a tennis-specific graded test in which five different intensity levels were applied randomly. Each intensity level was intended to simulate a game of singles tennis and comprised six 14 s periods of activity alternated with 20 s of active rest. Oxygen consumption (VO2) and heart rate (HR) were measured continuously and each player's rate of perceived exertion (RPE) was recorded at the end of each intensity level. Rate of energy expenditure (EEVO2) during the test was calculated using the sum of VO2 during play and the 'O-2 debt' during recovery, divided by the duration of the activity. There were significant individual linear relationships between EEVO2 and RPE, EEVO2 and HR, (rgreater than or equal to0.89 rgreater than or equal to0.93; p

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Conventional methods to determine surface diffusion of adsorbed molecules are proven to be inadequate for strongly adsorbing vapors on activated carbon. Knudsen diffusion permeability (B-k) for strongly adsorbing vapors cannot be directly estimated from that of inert gases such as helium. In this paper three models are considered to elucidate the mechanism of surface diffusion in activated carbon. The transport mechanism in all three models is a combination of Knudsen diffusion, viscous flow and surface diffusion. The collision reflection factor f (which is the fraction of molecules undergoing collision to the solid surface over reflection from the surface) of the Knudsen diffusivity is assumed to be a function of loading. It was found to be 1.79 in the limit of zero loading, and decreases as loading increases. The surface diffusion permeability increases sharply at very low pressures and then starts to decrease after it has reached a maximum (B(mum)s) at a threshold pressure. The initial rapid increase in the total permeability is mainly attributed to surface diffusion. Interestingly the B(mum)s for all adsorbates appear at the same volumetric adsorbed phase concentration, suggesting that the volume of adsorbed molecules may play an important role in the surface diffusion mechanism in activated carbon. (C) 2003 Elsevier Ltd. All rights reserved.

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A new wavelet-based adaptive framework for solving population balance equations (PBEs) is proposed in this work. The technique is general, powerful and efficient without the need for prior assumptions about the characteristics of the processes. Because there are steeply varying number densities across a size range, a new strategy is developed to select the optimal order of resolution and the collocation points based on an interpolating wavelet transform (IWT). The proposed technique has been tested for size-independent agglomeration, agglomeration with a linear summation kernel and agglomeration with a nonlinear kernel. In all cases, the predicted and analytical particle size distributions (PSDs) are in excellent agreement. Further work on the solution of the general population balance equations with nucleation, growth and agglomeration and the solution of steady-state population balance equations will be presented in this framework. (C) 2002 Elsevier Science B.V. All rights reserved.

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We develop a method for determining the elements of the pressure tensor at a radius r in a cylindrically symmetric system, analogous to the so-called method of planes used in planar systems [B. D. Todd, Denis J. Evans, and Peter J. Daivis, Phys. Rev. E 52, 1627 (1995)]. We demonstrate its application in determining the radial shear stress dependence during molecular dynamics simulations of the forced flow of methane in cylindrical silica mesopores. Such expressions are useful for the examination of constitutive relations in the context of transport in confined systems.

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A Embrapa, na inten????o de operacionalizar a gest??o dos seus planos estrat??gicos (Plano Diretor da Embrapa ??? PDE e Planos Diretores das Unidades ??? PDUs) desenvolveu a metodologia Mogest para a implementa????o do seu Modelo de Gest??o Estrat??gica (MGE), no ??mbito corporativo e de suas 40 unidades de neg??cio, com base na modifica????o do m??todo Balanced Scorecard ??? BSC, de Kaplan. Posteriormente, ap??s a implementa????o dos MGEs, no per??odo de 1999 at?? os dias atuais, inicia-se e desenvolve-se a fase de acompanhamento por meio da elabora????o do m??todo MGE/Acompanha. Este trabalho aborda, de forma modificada, o uso do diagrama elaborado por Norton, apud Coutinho (2002), para acompanhar/avaliar a implementa????o do BSC para uma organiza????o orientada ?? estrat??gia, inserido no m??todo MGE/Acompanha (2000), elaborado pela Equipe MGE e aplicado em uma das unidades de neg??cio da Embrapa. Os resultados mostraram a efici??ncia do m??todo e proporcionaram a internaliza????o do conceito ???painel de bordo???, desenvolvido no software Oracle BSC (OBSC).

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A institui????o do Programa Pr??-equidade de G??nero ?? o reconhecimento p??blico da desigualdade de tratamento e de oportunidades, que ainda permanece entre mulheres e homens. A implementa????o ?? consolidada com a coloca????o em pr??tica dos planos de a????es firmados entre a Secretaria Especial de Pol??ticas para as Mulheres (SPM) e as organiza????es aderentes. A pesquisa explorat??ria teve como objetivo apresentar o programa e discuti-lo com base no modelo "policy cycle como aprendizado", de Silva e Melo (2000). Os resultados subsidiar??o pesquisa futura sobre a avalia????o do programa. Dentro da estrat??gia adotada, a coleta de dados ocorreu em documentos institucionais e dados bibliogr??ficos em mar??o de 2009, com o seguinte resultado: a avalia????o n??o trata de forma clara da efetividade e da sustentabilidade do programa. Este trabalho est?? dividido em seis partes: descri????o do m??todo utilizado; apresenta????o do Programa Pro-equidade de G??nero; avalia????o de suas duas primeiras edi????es; breve contextualiza????o das pol??ticas p??blicas no Brasil e o modelo "policy cicle como aprendizado"; rela????es entre o programa e o modelo; e considera????es finais.

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Utiliza-se o método coordenada geradora Hartree-Fock para gerar bases Gaussianas adaptadas para os átomos de Li (Z=3) até Xe (Z=54). Neste método, integram-se as equações de Griffin-Hill-Wheeler-Hartree-Fock através da técnica de discretização integral. Comparam-se as funções de ondas geradas neste trabalho com as funções de ondas Roothaan-Hartree-Fock de Clementi e Roetti (1974) e com outros conjuntos de bases relatados na literatura. Para os átomos estudados aqui, os erros em nossas energias totais relativos aos limites numéricos Hartree-Fock são sempre menores que 7,426 milihartree.

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Este estudo analisa a evolução das parcerias na implementação da Politica de Assistência Social no município de Serra, Espírito Santo (ES), contribuindo para a discussão sobre a complementariedade das ações previstas na Política Nacional de Assistência Social (PNAS). Trata-se de um estudo qualitativo, referenciado no método crítico-dialético. A estratégia metodológica baseou-se na pesquisa bibliográfica e documental. Os dados empíricos resultam do levantamento e análise dos Relatórios das Conferências Nacionais de Assistência Social; dos Planos e Relatórios Municipais de Gestão na área da Assistência Social; dos termos de convênio estabelecidos com as entidades em 2013. O crescimento das parcerias para execução da PNAS tem relação com a tendência nacional de focalização, descentralização e privatização das políticas sociais. Isso ajuda-nos a compreender essa tendência a nível municipal. As ideias que justificam a realização das parcerias relacionam-se com o neoliberalismo e a reforma do Estado e, também, com a perspectiva de fortalecimento da participação social a partir do contexto do debate que antecede a conformação da Constituição de 1988. O próprio histórico da assistência no Brasil revela que muitas das entidades já executavam ações antes da Lei Orgânica da Assistência Social (LOAS) e apenas se adaptaram à nova legislação. No caso do município pesquisado, o crescimento registrado no número de entidades entre 2001 e 2012 foi de 133,3%. Observamos, ainda, que as entidades não governamentais tem se constituído como a forma primeira de prestação dos serviços socioassistenciais. A maior parte das entidades é de cunho religioso e atua em apenas um âmbito da proteção social. A pesquisa reforça a importância do monitoramento e avaliação das parcerias realizadas e a necessidade da garantia da transparência e publicização das informações na área da assistência, de modo a contribuir com o controle social.