1000 resultados para Multidimensional. Desenvolvimento. Converg


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Multidimensional spatiotemporal parametric simultons (simultaneous solitary waves) are possible in a nonlinear chi((2)) medium with a Bragg grating structure, where large effective dispersion occurs near two resonant band gaps for the carrier and second-harmonic field, respectively. The enhanced dispersion allows much reduced interaction lengths, as compared to bulk medium parametric simultons. The nonlinear parametric band-gap medium permits higher-dimensional stationary waves to form. In addition, solitons can occur with lower input powers than conventional nonlinear Schrodinger equation gap solitons. In this paper, the equations for electromagnetic propagation in a grating structure with a parametric nonlinearity are derived from Maxwell's equation using a coupled mode Hamiltonian analysis in one, two, and three spatial dimensions. Simultaneous solitary wave solutions are proved to exist by reducing the equations to the coupled equations describing a nonlinear parametric waveguide, using the effective-mass approximation (EMA). Exact one-dimensional numerical solutions in agreement with the EMA solutions are also given. Direct numerical simulations show that the solutions have similar types of stability properties to the bulk case, providing the carrier waves are tuned to the two Bragg resonances, and the pulses have a width in frequency space less than the band gap. In summary, these equations describe a physically accessible localized nonlinear wave that is stable in up to 3 + 1 dimensions. Possible applications include photonic logic and switching devices. [S1063-651X(98)06109-1].

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We consider the quantum theory of three fields interacting via parametric and repulsive quartic couplings. This can be applied to treat photonic chi((2)) and chi((3)) interactions, and interactions in atomic Bose-Einstein condensates or quantum Fermi gases, describing coherent molecule formation together with a-wave scattering. The simplest two-particle quantum solitons or bound-state solutions of the idealized Hamiltonian, without a momentum cutoff, are obtained exactly. They have a pointlike structure in two and three dimensions-even though the corresponding classical theory is nonsingular. We show that the solutions can be regularized with a momentum cutoff. The parametric quantum solitons have much more realistic length scales and binding energies than chi((3)) quantum solitons, and the resulting effects could potentially be experimentally tested in highly nonlinear optical parametric media or interacting matter-wave systems. N-particle quantum solitons and the ground state energy are analyzed using a variational approach. Applications to atomic/molecular Bose-Einstein condensates (BEC's) are given, where we predict the possibility of forming coupled BEC solitons in three space dimensions, and analyze superchemistry dynamics.

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Recent advances in the control of molecular engineering architectures have allowed unprecedented ability of molecular recognition in biosensing, with a promising impact for clinical diagnosis and environment control. The availability of large amounts of data from electrical, optical, or electrochemical measurements requires, however, sophisticated data treatment in order to optimize sensing performance. In this study, we show how an information visualization system based on projections, referred to as Projection Explorer (PEx), can be used to achieve high performance for biosensors made with nanostructured films containing immobilized antigens. As a proof of concept, various visualizations were obtained with impedance spectroscopy data from an array of sensors whose electrical response could be specific toward a given antibody (analyte) owing to molecular recognition processes. In addition to discussing the distinct methods for projection and normalization of the data, we demonstrate that an excellent distinction can be made between real samples tested positive for Chagas disease and Leishmaniasis, which could not be achieved with conventional statistical methods. Such high performance probably arose from the possibility of treating the data in the whole frequency range. Through a systematic analysis, it was inferred that Sammon`s mapping with standardization to normalize the data gives the best results, where distinction could be made of blood serum samples containing 10(-7) mg/mL of the antibody. The method inherent in PEx and the procedures for analyzing the impedance data are entirely generic and can be extended to optimize any type of sensor or biosensor.

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The aim of this study was to identify the psycho-musical factors that govern time evaluation in Western music from baroque, classic, romantic, and modern repertoires. The excerpts were previously found to represent variability in musical properties and to induce four main categories of emotions. 48 participants (musicians and nonmusicians) freely listened to 16 musical excerpts (lasting 20 sec. each) and grouped those that seemed to have the same duration. Then, participants associated each group of excerpts to one of a set of sine wave tones varying in duration from 16 to 24 sec. Multidimensional scaling analysis generated a two-dimensional solution for these time judgments. Musical excerpts with high arousal produced an overestimation of time, and affective valence had little influence on time perception. The duration was also overestimated when tempo and loudness were higher, and to a lesser extent, timbre density. In contrast, musical tension had little influence.

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We consider solutions to the second-harmonic generation equations in two-and three-dimensional dispersive media in the form of solitons localized in space and time. As is known, collapse does not take place in these models, which is why the solitons may be stable. The general solution is obtained in an approximate analytical form by means of a variational approach, which also allows the stability of the solutions to be predicted. Then, we directly simulate the two-dimensional case, taking the initial configuration as suggested by the variational approximation. We thus demonstrate that spatiotemporal solitons indeed exist and are stable. Furthermore, they are not, in the general case, equivalent to the previously known cylindrical spatial solitons. Direct simulations generate solitons with some internal oscillations. However, these oscillations neither grow nor do they exhibit any significant radiative damping. Numerical solutions of the stationary version of the equations produce the same solitons in their unperturbed form, i.e., without internal oscillations. Strictly stable solitons exist only if the system has anomalous dispersion at both the fundamental harmonic and second harmonic (SH), including the case of zero dispersion at SH. Quasistationary solitons, decaying extremely slowly into radiation, are found in the presence of weak normal dispersion at the second-harmonic frequency.

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This study (a) examined the multidimensionality of both group cohesion and group performance, (b) investigated the relationship between group-level task and social cohesion and group effectiveness, and (c) examined the longitudinal changes in cohesion and performance and the direction of effect between cohesion and performance. First, the authors hypothesized that both task and social cohesion would predict positively all dimensions of group performance. Second, that a stronger relationship would be observed between task cohesion and task effectiveness and between social cohesion and system viability. Third, that all dimensions of cohesion and performance would increase over time. Finally, that cohesion would be both the antecedent and the consequence of performance but that the performance-cohesion relationship would be stronger than the cohesion-performance relationship. Results supported the hypothesized one-to-one relationship between specific dimensions of group cohesion and group performance. Task cohesion was the sole predictor of self-rated performance at both Time 1 and Time 2, whereas social cohesion was the only predictor of system viability at Time 1 and the stronger predictor at Time 2. Social cohesion at Time 2 predicted performance on group task. However, no longitudinal changes were found in cohesion or performance. Finally, group cohesion was found to be the antecedent, but not the consequence, of group performance.

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Sensitivity of output of a linear operator to its input can be quantified in various ways. In Control Theory, the input is usually interpreted as disturbance and the output is to be minimized in some sense. In stochastic worst-case design settings, the disturbance is considered random with imprecisely known probability distribution. The prior set of probability measures can be chosen so as to quantify how far the disturbance deviates from the white-noise hypothesis of Linear Quadratic Gaussian control. Such deviation can be measured by the minimal Kullback-Leibler informational divergence from the Gaussian distributions with zero mean and scalar covariance matrices. The resulting anisotropy functional is defined for finite power random vectors. Originally, anisotropy was introduced for directionally generic random vectors as the relative entropy of the normalized vector with respect to the uniform distribution on the unit sphere. The associated a-anisotropic norm of a matrix is then its maximum root mean square or average energy gain with respect to finite power or directionally generic inputs whose anisotropy is bounded above by a≥0. We give a systematic comparison of the anisotropy functionals and the associated norms. These are considered for unboundedly growing fragments of homogeneous Gaussian random fields on multidimensional integer lattice to yield mean anisotropy. Correspondingly, the anisotropic norms of finite matrices are extended to bounded linear translation invariant operators over such fields.

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O ??ndice de Desenvolvimento da Educa????o B??sica (Ideb) ?? um indicador que combina informa????es de fluxo e de desempenho dos alunos, criado para promover um sistema de accountability visando a melhoria da qualidade da educa????o no pa??s. Ao elaborar metas detalhadas para cada rede e escola ??? com as quais governadores e prefeitos se comprometeram por meio do Compromisso Todos Pela Educa????o ??? ao calcular e divulgar amplamente os resultados do Ideb, o Instituto Nacional de Estudos e Pesquisas Educacionais An??sio Teixeira (Inep) possibilitou que os atores educacionais pudessem ser responsabilizados pelos resultados de sua unidade e que o Minist??rio da Educa????o (MEC) identificasse e premiasse as escolas que atingem as metas, mas tamb??m oferecesse assist??ncia t??cnica e financeira para as redes com piores resultados. Entre os principais resultados j?? alcan??ados, pode-se destacar que o Ideb do pa??s para os anos iniciais do ensino fundamental cresceu de 3,8, em 2005, para 4,2, em 2007

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Em dezembro de 2001, o Proeta foi criado pela Empresa Brasileira de Pesquisa Agropecu??ria (Embrapa) com apoio financeiro do Fundo Multilateral de Investimentos do Banco Interamericano de Desenvolvimento (Fumin/BID), por meio de um acordo de coopera????o t??cnica n??o-reembols??vel. O programa tem o objetivo de contribuir para a transfer??ncia de tecnologias e conhecimentos gerados pela Embrapa para empreendimentos de base tecnol??gica, mediante a utiliza????o do processo de incuba????o de empresas. Para concretizar a iniciativa, foram estabelecidas experi??ncias-piloto em cinco unidades de pesquisa da Embrapa, estrategicamente situadas nas regi??es Nordeste, Centro-Oeste e Sudeste. Entre os resultados e avan??os obtidos merecem destaque 21 tecnologias disponibilizadas, 14 conv??nios firmados com incubadoras, 16 propostas de neg??cios apresentadas, 14 empresas pr??-selecionadas e incubadas, e uma empresa graduada. A consolida????o das alian??as e parcerias no processo de incuba????o resultou em um sistema de inova????o que auxilia o desenvolvimento sustent??vel da cadeia produtiva do agroneg??cio, gerando benef??cios para a sociedade em geral

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O estudo de caso trata da implementa????o do Bolsa Fam??lia, um programa de transfer??ncia de renda para fam??lias pobres, condicionada ao atendimento de exig??ncias espec??ficas por parte dos benefici??rios (comumente conhecida como ???transfer??ncia condicionada de renda???). Ap??s a descri????o dos antecedentes, apontando experi??ncias em n??vel local que inspiraram a pol??tica nacional, o autor apresenta as fases de implementa????o do programa, identificando dificuldades, cr??ticas recebidas e solu????es encontradas pelo governo federal. Em seguida, documenta impactos na redu????o da pobreza e da desigualdade social, e analisa a expans??o do espa??o p??blico originada da experi??ncia do Bolsa Fam??lia. O caso ilustra situa????o que suscita reflex??o e an??lise dos alunos com rela????o ao desenho e desenvolvimento de programa complexo de pol??tica social, podendo se desdobrar em novas pesquisas sobre o Bolsa Fam??lia, seus fatores cr??ticos e de sucesso

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Gerenciar pesquisa, desenvolvimento tecnol??gico e inova????o no Brasil ?? um grande desafio. S?? no ano de 2004, a ind??stria brasileira desembolsou cerca de US$ 4 bilh??es, em royalties, pelo uso de tecnologias importadas. Com a Lei n. 9.991/00, as empresas do Setor El??trico Brasileiro (SEB) obrigaram-se a investir, anualmente, o m??nimo de 1% da Receita Operacional L??quida (ROL) em Projetos de Pesquisa e Desenvolvimento Tecnol??gico (P&D). O processo do Programa Eletronorte de Pesquisa e Desenvolvimento Tecnol??gico (PEPD) ?? inovador e foi estruturado utilizando redes de conhecimentos e parceiros na gest??o profissional da P&D. Esse trabalho avalia como o PEPD gerou uma verdadeira revolu????o empresarial a partir da GTI, Gest??o da Tecnologia e da Inova????o, tornando-se uma importante estrat??gia de competitividade e desempenho. O PEPD possibilitou a obten????o de expressivos resultados como o aumento de tr??s vezes dos recursos investidos em P&D, solu????o de problemas empresariais cr??ticos, redu????o de custos e adiamento de investimentos, aumento das inser????es tecnol??gica e social, aumento do n??mero de titula????es (gradua????o, p??s-gradua????o, mestrado e doutorado). O que ratifica a nova dimens??o assumida pela GTI na transforma????o da ind??stria de energia el??trica brasileira

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O caso versa sobre a coopera????o entre o Canad?? e a Jord??nia no desenvolvimento de uma estrat??gia denominada ???Educa????o para o Emprego e Capacita????o T??cnica e Vocacional (E-TVET)???. Dentro do Minist??rio do Trabalho jordaniano, ??rg??o que liderava a a????o, foi criada uma unidade de coordena????o, para qual foi disponibilizada pela coopera????o canadense uma assessora com expertise em educa????o, Brenda Cooke. Sua tarefa era apoiar o estabelecimento e a operacionaliza????o dessa unidade, conforme termo de refer??ncia. Contando com a boa assist??ncia t??cnica da consultora, o projeto deu certo e gerou li????es importantes que s??o descritas no caso, como a administra????o adequada das expectativas dos atores envolvidos, abordagem participativa para estabelecer as regras de funcionamento da unidade etc. O caso presta-se ao ensino de temas como coopera????o internacional, lideran??a, gest??o de projetos e outros

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O caso retrata a situa????o de um especialista em pol??ticas p??blicas e gest??o governamental (EPPGG), rec??m-empossado, sem experi??ncia no setor p??blico e que ?? nomeado em cargo de coordena????o em um minist??rio. Ele dever?? gerenciar uma equipe respons??vel pelo acompanhamento de projetos em ??mbito nacional que apresenta baixos resultados. A equipe ?? heterog??nea quanto ?? capacita????o, situa????o funcional e sal??rios, al??m de apresentar pontos de conflito. Ap??s avaliar a situa????o, o gestor apresenta aos superiores sugest??es de a????es visando melhorar o desempenho da equipe

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O Programa de Reabilita????o Profissional (PRP) no Hospital de Cl??nicas de Porto Alegre visa ?? reinser????o laboral dos trabalhadores afastados por adoecimento e com restri????es quanto ao desempenho de suas fun????es, respeitando suas necessidades e demandas institucionais. O PRP ?? constitu??do por profissionais das ??reas de Gest??o de Pessoas, Medicina Ocupacional, Psicologia e Servi??o Social. A equipe avalia cada funcion??rio, a atividade a ser exercida e as caracter??sticas da ??rea de trabalho. O trabalhador ?? sistematicamente acompanhado pela equipe durante o per??odo de inser????o na nova atividade. Em 2004, 79% dos trabalhadores conclu??ram o treinamento. O trabalho integrado da equipe aliado ??s pol??ticas institucionais possibilita o acompanhamento sistem??tico e individual desses trabalhadores, a sensibiliza????o ?? tem??tica da reabilita????o e dos processos de sa??de e adoecimento no trabalho e a efetiva????o de um conjunto de a????es institucionais de preven????o

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O setor el??trico brasileiro, historicamente, possui modelo autorit??rio de planejamento e implanta????o dos empreendimentos. Os grandes projetos desenvolvimentistas s??o oriundos do per??odo dos governos militares. Popula????es atingidas por impactos de barragens sempre reivindicaram pol??ticas articuladas de compensa????o por parte das empresas e do governo. A partir de 2003, a Eletronorte adotou o planejamento participativo para elabora????o de um plano de desenvolvimento regional ??? PPDJUS ??? como compensa????o pelos impactos da UHE Tucuru?? nos cinco munic??pios a Jusante, iniciativa sem precedentes no Brasil. O PPDJUS hoje articula as pol??ticas de planejamento e gest??o do territ??rio e de recursos h??dricos do Minist??rio do Desenvolvimento Agr??rio (MDA), do Minist??rio do Meio Ambiente (MMA), do Minist??rio da Integra????o Nacional (MIN), da Secretaria Especial de Abastecimento e Pre??os (Seap), da Ag??ncia de Desenvolvimento da Amaz??nia (ADA) e da Eletronorte, entre outros ??rg??os. Possui conselhos gestores regional e municipais e c??maras t??cnicas, avan??ado modelo de gest??o participativa