925 resultados para post-Newtonian approximation to general relativity
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The exchange energy of an arbitrary collinear-spin many-body system in an external magnetic field is a functional of the spin-resolved charge and current densities, E(x)[n(up arrow), n(down arrow), j(up arrow), j(down arrow)]. Within the framework of density-functional theory (DFT), we show that the dependence of this functional on the four densities can be fully reconstructed from either of two extreme limits: a fully polarized system or a completely unpolarized system. Reconstruction from the limit of an unpolarized system yields a generalization of the Oliver-Perdew spin scaling relations from spin-DFT to current-DFT. Reconstruction from the limit of a fully polarized system is used to derive the high-field form of the local-spin-density approximation to current-DFT and to magnetic-field DFT.
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We obtain adjustments to the profile likelihood function in Weibull regression models with and without censoring. Specifically, we consider two different modified profile likelihoods: (i) the one proposed by Cox and Reid [Cox, D.R. and Reid, N., 1987, Parameter orthogonality and approximate conditional inference. Journal of the Royal Statistical Society B, 49, 1-39.], and (ii) an approximation to the one proposed by Barndorff-Nielsen [Barndorff-Nielsen, O.E., 1983, On a formula for the distribution of the maximum likelihood estimator. Biometrika, 70, 343-365.], the approximation having been obtained using the results by Fraser and Reid [Fraser, D.A.S. and Reid, N., 1995, Ancillaries and third-order significance. Utilitas Mathematica, 47, 33-53.] and by Fraser et al. [Fraser, D.A.S., Reid, N. and Wu, J., 1999, A simple formula for tail probabilities for frequentist and Bayesian inference. Biometrika, 86, 655-661.]. We focus on point estimation and likelihood ratio tests on the shape parameter in the class of Weibull regression models. We derive some distributional properties of the different maximum likelihood estimators and likelihood ratio tests. The numerical evidence presented in the paper favors the approximation to Barndorff-Nielsen`s adjustment.
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The Birnbaum-Saunders regression model is becoming increasingly popular in lifetime analyses and reliability studies. In this model, the signed likelihood ratio statistic provides the basis for testing inference and construction of confidence limits for a single parameter of interest. We focus on the small sample case, where the standard normal distribution gives a poor approximation to the true distribution of the statistic. We derive three adjusted signed likelihood ratio statistics that lead to very accurate inference even for very small samples. Two empirical applications are presented. (C) 2010 Elsevier B.V. All rights reserved.
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Cdc25 phosphatases involved in cell cycle checkpoints are now active targets for the development of anti-cancer therapies. Rational drug design would certainly benefit from detailed structural information for Cdc25s. However, only apo- or sulfate-bound crystal structures of the Cdc25 catalytic domain have been described so far. Together with previously available crystalographic data, results from molecular dynamics simulations, bioinformatic analysis, and computer-generated conformational ensembles shown here indicate that the last 30-40 residues in the C-terminus of Cdc25B are partially unfolded or disordered in solution. The effect of C-terminal flexibility upon binding of two potent small molecule inhibitors to Cdc25B is then analyzed by using three structural models with variable levels of flexibility, including an equilibrium distributed ensemble of Cdc25B backbone conformations. The three Cdc25B structural models are used in combination with flexible docking, clustering, and calculation of binding free energies by the linear interaction energy approximation to construct and validate Cdc25B-inhibitor complexes. Two binding sites are identified on top and beside the Cdc25B active site. The diversity of interaction modes found increases with receptor flexibility. Backbone flexibility allows the formation of transient cavities or compact hydrophobic units on the surface of the stable, folded protein core that are unexposed or unavailable for ligand binding in rigid and densely packed crystal structures. The present results may help to speculate on the mechanisms of small molecule complexation to partially unfolded or locally disordered proteins.
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Esta tese estuda as competências essenciais requeridas dos profissionais em vendas de bens perecíveis diante das mudanças ambientais e novas estratégias de relacionamento entre as indústrias de alimentação e seus canais de marketing. Há revisões teóricas sobre marketing e venda pessoal no lado da Administração e sobre competências no lado da Psicologia. Da revisão teórica foram selecionadas 16 competências chave para compor um dicionário, convenientes ao atual contexto de relacionamento entre comprador e vendedor. A pesquisa foi conduzida entre participantes de comitês do Movimento ECR Brasil, funcionários de supermercados e de indústrias de alimentação (n = 192). Empregaram-se as técnicas estatísticas da análise fatorial exploratória e da análise fatorial confirmatória e o modelo teórico foi gerado com três dimensões - suporte à competitividade, relacionamento eficaz e integração operacional - abrangendo 12 competências essenciais. Foram testadas as validades convergente, discriminante e nomológica dos constructos do modelo teórico. Quanto às medidas de ajustamento global do modelo teórico mais o índice esperado de validação cruzada (ECVI) foi possível constatar que o modelo demonstrou consistência com os dados e teve uma boa aproximação da população (X² = 68,15, DF = 51, p = 0,054, RMSEA = 0,042). A avaliação dos resultados do modelo de medidas revelou evidência parcial quanto à validade dos constructos e baixa fidedignidade quanto aos indicadores do modelo teórico.
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A inserção do princípio da eficiência na Constituição Federal de 1988 vem provocando a necessidade de melhor atuação e aperfeiçoamento dos Tribunais de Contas no Brasil, visando ao melhor atendimento das demandas da sociedade. O desenvolvimento de ações para o acompanhamento dessas demandas é de suma importância para o fortalecimento dos órgãos de controle externo, cuja credibilidade depende da eficiência e da eficácia com que respondem às demandas sociais. A presente pesquisa analisou até que ponto o uso de tecnologia de informação emprestou eficiência ao atendimento de demandas da sociedade pelo Tribunal de Contas do Estado de Pernambuco. Quanto à metodologia, a pesquisa foi descritiva, de campo e estudo de caso. O universo foi composto pelos servidores do Tribunal de Contas do Estado de Pernambuco, sendo utilizadas duas populações amostrais. Os dados foram coletados por entrevistas e questionário e tratados com abordagem qualitativa e estatística descritiva. Verificou-se que, apesar dos avanços já alcançados na gestão administrativa do órgão, inclusive com a disseminação do uso de tecnologia de informação, há uma carência de aprimoramento no recebimento e no acompanhamento das demandas recebidas. Identificou-se que a disponibilização de informações gerenciais sobre essas demandas repercutirá na eficiência administrativa da instituição. O estudo sugere um conjunto de ações que podem ser implantadas e desenvolvidas no Tribunal de Contas do Estado de Pernambuco, com o objetivo de elevar a sua eficiência administrativa no atendimento às demandas sociais. Para identificação de um referencial de boas práticas, visando à implementação de mudanças, foi utilizada a tecnologia de gestão benchmarking. A unidade que serviu como parâmetro foi a Ouvidoria do próprio Tribunal, com realização de benchmarking interno e de processo
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Esta tese é uma reflexão sobre a construção de escritas da História do Brasil em museus, a partir da década de 1920, momento fulcral para o estabelecimento de uma “pedagogia da nacionalidade” republicana, que tem por suporte o discurso museal. Alguns dos esforços político-pedagógicos dessas instituições foram observados, com o objetivo de compreender as principais características de um paradigma educativo para o saber histórico nos museus. Assim, a análise das comemorações cívicas, dos guias de divulgação e das exposições permitiu uma aproximação das ativações memoriais ensejadas pelos atores dos museus, com atenção para as continuidades, as negociações e as transformações dos projetos, especialmente em sua dimensão pedagógica. O Museu Mariano Procópio foi selecionado para a realização de um estudo de caso, tanto por suas especificidades, que nos induzem a pensar o “concerto” dos museus nacionais a partir do interior do país como pela relevância de seu acervo e pela intensidade de ações educativas desenvolvidas na gestão de Geralda Armond (1944-1980). A gestão Armond é o foco da tese, sendo marcada pela defesa da continuidade institucional e do enquadramento da memória da família Lage; pela luta pela sustentação material do Museu, inclusive com uma forte aproximação com o regime civil e militar; e pela busca da profissionalização de quadros e do dinamismo das ações. Os resultados atentam para a multiplicidade e fragilidade na construção identitária do Museu, associada ao fato de ser um museu “municipal”. Uma situação que explica, ao menos em parte, seu esquecimento no cenário nacional a despeito de seu acervo expressivo e das articulações encetadas com o sistema escolar, por meio do fortalecimento do sentido cívico de suas ações pedagógicas.
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Esta tese teve como objetivo identificar qual o valor social considerado pelo Comitê de Pronunciamentos Contábeis (CPC) na emissão de seus pronunciamentos contábeis: aproximação ou distanciamento das normas contábeis brasileiras às internacionais. A contabilidade mundial se encontra em um momento histórico, marcado pelo processo de convergência das normas contábeis e da criação de uma linguagem universal. No processo, cada país tem uma abordagem, que pode variar da convergência, onde os países mantêm suas instituições normativas, ao endosso, onde é efetuada uma tradução dos pronunciamentos contábeis. No Brasil, o processo é conduzido pelo CPC, formado sob a égide de seis instituições privadas brasileiras, cada uma representando um diferente grupo de agentes econômicos. O CPC emite um pronunciamento, que entra em audiência pública por no mínimo 30 dias. A nova versão é resultado da análise das sugestões recebidas. Utilizamos na tese a Teoria Tridimensional do Direito, de Miguel Reale, composta por norma, fato e valor, que estão sempre presentes e correlacionados de maneira funcional e dialética, e sofrem interferência do Poder, que determina quais os valores positivos, a serem preservados, e quais os valores negativos, a serem proibidos. Foram utilizados os pronunciamentos contábeis emitidos pelo CPC no que diz respeito a Conceituação Geral e Evidenciação, antes e depois da audiência pública, a norma internacional em que se baseia o pronunciamento brasileiro e as sugestões recebidas pelo CPC sobre os pronunciamentos contábeis. Os resultados apontam para uma forte associação entre sugestões que tinham como finalidade a aproximação das normas internacionais e a aceitação por parte do CPC. Além disso, os atores envolvidos no processo passam a aceitar a aproximação dos pronunciamentos contábeis brasileiros aos internacionais como realidade e aprenderam que o caminho para modificação de algum ponto do pronunciamento brasileiro é a alteração do pronunciamento do IASB.
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This work aims to analyze the interaction and the effects of administered prices in the economy, through a DSGE model and the derivation of optimal monetary policies. The model used is a standard New Keynesian DSGE model of a closed economy with two sectors companies. In the first sector, free prices, there is a continuum of firms, and in the second sector of administered prices, there is a single firm. In addition, the model has positive trend inflation in the steady state. The model results suggest that price movements in any sector will impact on both sectors, for two reasons. Firstly, the price dispersion causes productivity to be lower. As the dispersion of prices is a change in the relative price of any sector, relative to general prices in the economy, when a movement in the price of a sector is not followed by another, their relative weights will change, leading to an impact on productivity in both sectors. Second, the path followed by the administered price sector is considered in future inflation expectations, which is used by companies in the free sector to adjust its optimal price. When this path leads to an expectation of higher inflation, the free sector companies will choose a higher mark-up to accommodate this expectation, thus leading to higher inflation trend when there is imperfect competition in the free sector. Finally, the analysis of optimal policies proved inconclusive, certainly indicating that there is influence of the adjustment model of administered prices in the definition of optimal monetary policy, but a quantitative study is needed to define the degree of impact.
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Trabalho apresentado no XXXV CNMAC, Natal-RN, 2014.
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Content marketing refers to marketing format that involves the creation and sharing of media and publishing content in order to acquire customers. It is focused not on selling, but on communicating with customers and prospects. In today world´s, a trend has been seen in brands becoming publishers in order to keep up with their competition and more importantly to keep their base of fans and followers. Content Marketing is making companies to engage consumers by publishing engaging and value-filled content. This study aims to investigate if there is a link between brand engagement and Facebook Content Marketing practices in the e-commerce industry in Brazil. Based on the literature review, this study defines brand engagement on Facebook as the numbers of "likes" "comments" and "shares" that a company receives from its fans. These actions reflect the popularity of the brand post and leads to engagement. The author defines a scale where levels of Content Marketing practices are developed in order to analyze brand posts on Facebook of an ecommerce company in Brazil. The findings reveal that the most important criterion for the company is the one regarding the picture of the post, where it examines whether the photo content is appealing to the audience. Moreover, it was perceived that the higher the level of these criterion in a post, the greater the number of likes, comments and shares the post receives. The time when a post is published does not present a significant role in determining customer engagement and the most important factor within a publication is to reach the maximum level in the Content Marketing Scale.
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Although formal methods can dramatically increase the quality of software systems, they have not widely been adopted in software industry. Many software companies have the perception that formal methods are not cost-effective cause they are plenty of mathematical symbols that are difficult for non-experts to assimilate. The Java Modelling Language (short for JML) Section 3.3 is an academic initiative towards the development of a common formal specification language for Java programs, and the implementation of tools to check program correctness. This master thesis work shows how JML based formal methods can be used to formally develop a privacy sensitive Java application. This is a smart card application for managing medical appointments. The application is named HealthCard. We follow the software development strategy introduced by João Pestana, presented in Section 3.4. Our work influenced the development of this strategy by providing hands-on insight on challenges related to development of a privacy sensitive application in Java. Pestana’s strategy is based on a three-step evolution strategy of software specifications, from informal ones, through semiformal ones, to JML formal specifications. We further prove that this strategy can be automated by implementing a tool that generates JML formal specifications from a welldefined subset of informal software specifications. Hence, our work proves that JML-based formal methods techniques are cost-effective, and that they can be made popular in software industry. Although formal methods are not popular in many software development companies, we endeavour to integrate formal methods to general software practices. We hope our work can contribute to a better acceptance of mathematical based formalisms and tools used by software engineers. The structure of this document is as follows. In Section 2, we describe the preliminaries of this thesis work. We make an introduction to the application for managing medical applications we have implemented. We also describe the technologies used in the development of the application. This section further illustrates the Java Card Remote Method Invocation communication model used in the medical application for the client and server applications. Section 3 introduces software correctness, including the design by contract and the concept of contract in JML. Section 4 presents the design structure of the application. Section 5 shows the implementation of the HealthCard. Section 6 describes how the HealthCard is verified and validated using JML formal methods tools. Section 7 includes some metrics of the HealthCard implementation and specification. Section 8 presents a short example of how a client-side of a smart card application can be implemented while respecting formal specifications. Section 9 describes a prototype tools to generate JML formal specifications from informal specifications automatically. Section 10 describes some challenges and main ideas came acrorss during the development of the HealthCard. The full formal specification and implementation of the HealthCard smart card application presented in this document can be reached at https://sourceforge.net/projects/healthcard/.
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This survey has to general objective to evaluate the Food Safety Policy implemented by Restaurantes Populares do Rio Grande do Norte. The survey is qualitative of type exploratory and descriptive. The universe of survey is all Units of Food and Nutrition (UAN) of the Restaurantes Populares do Rio Grande do Norte. To collects of data were used two instruments: interview and form. The interviews were intended to analyze the four axes of the Food Safety: access, food quality, production and marketing of food and organizational arrangement. The form was used to check the quality of nutrition and sanitary-hygienic food served. We used two types of forms: a spreadsheet with the weekly menu and the portions served to verify that the meals serve the nutritional needs proposed by the program; and the check-list of ANVISA to verify the sanitary-hygienic conditions in each unit. Through the survey data and analyses made observe that the access category have some problems such as lack of registration, lack of advertising of Restaurants and wastage of public resources, making policy that should be of included in a policy of exclusion. In the nutritional aspect there is neglect on the daily nutritional goal, because it is not accomplished nutritional analysis of menu offered, the nutritionists do not know what should be the nutritional value of meals served; in the hygienic-health aspect trough the problems identified is concludes that there is no guarantee of food quality hygienic-sanitary, committing the program as a Food Safety Program. About the production and marketing of food is observed some problems as: the goal of sale of meals is not achieved in full, the purchase of genres does not stimulate the local economy, nor generates jobs and income, and inefficient performance of the MEIOS's supervision. In the analysis of organizational arrangement is concluded that the partnerships are beneficial, despite some negative points, therefore, are these partnerships the problems of non-compliance, as both the MEIOS and Nutriti of important criteria established in the partnership. Therefore, it is understood that the Programa Restaurantes Populares in its original formulation is proposed to be a food safety policy, but has some problems that impossible to meet its goal, making it unprofitable like Food Safety Policy
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The current study presents the characteristics of self-efficacy of students of Administration course, who work and do not work. The study was conducted through a field research, descriptive, addressed quantitatively using statistical procedures. Was studied a population composed of 394 students distributed in three Higher Education Institutions, in the metropolitan region of Belém, in the State of Pará. The sampling was not probabilistic by accessibility, with a sample of 254 subjects. The instrument for data collection was a questionnaire composed of a set of questions divided into three sections: the first related to sociodemographic data, the second section was built to identify the work situation of the respondent and the third section was built with issues related to General Perceived Self-Efficacy Scale proposed by Schwarzer and Jerusalem (1999). Sociodemographic data were processed using methods of descriptive statistics. This procedure allowed characterizing the subjects of the sample. To identify the work situation, the analysis of frequency and percentage was used, which allowed to classify in percentage, the respondents who worked and those that did not work, and the data related to the scale of self-efficacy were processed quantitatively by the method of multivariate statistics using the software of program Statistical Package for Social Sciences for Windows - SPSS, version 17 from the process of Exploratory Factor Analysis. This procedure allowed characterizing the students who worked and the students who did not worked. The results were discussed based on Social Cognitive Theory from the construct of self-efficacy of Albert Bandura (1977). The study results showed a young sample, composed the majority of single women with work experience, and indicated that the characteristics of self-efficacy of students who work and students who do not work are different. The self-efficacy beliefs of students who do not work are based on psychological expectations, whereas the students who work demonstrated that their efficacy beliefs are sustained by previous experiences. A student who does not work proved to be reliant in their abilities to achieve a successful performance in their activities, believing it to be easy to achieve your goals and to face difficult situations at work, simply by invest a necessary effort and trust in their abilities. One who has experience working proved to be reliant in their abilities to conduct courses of action, although know that it is not easy to achieve your goals, and in unexpected situations showed its ability to solve difficult problems
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O lactofen, herbicida do grupo dos difenil éteres, é indicado para uso na cultura da soja, em pós-emergência, devido sua eficácia no controle de plantas daninhas latifoliadas. No presente trabalho, conduzido em casa-de-vegetação, foram utilizadas as cultivares de soja Foscarin-31, IAC-8 e IAC-9, tratadas com lactofen nas doses 0,018 e 0,36 kg de lactofen i.a./ha, aplicadas quando as plantas apresentavam a Segunda folha composta totalmente expandida. Aos quatro e doze dias após as aplicações, foram analisadas e descritos os sinais macroscópicos e microscópicos de intoxicação nos folíolos das folhas. Os resultados indicaram que o lactofen ocasionou expressivas alterações morfológicas externas e internas das folhas, nos locais onde foi depositado, e que a dose maior acentua os efeitos do produto sobre as plantas, sendo que as cultivares de soja apresentaram diferentes graus de sensibilidade ao produto.