abstract: A simulation study was conducted to explore the influence of partial loading invariance and partial intercept invariance on the latent mean comparison of the second-order factor within a higher-order confirmatory factor analysis (CFA) model. Noninvariant loadings or intercepts were generated to be at one of the two levels or both levels for a second-order CFA model. The numbers and directions of differences in noninvariant loadings or intercepts were also manipulated, along with total sample size and effect size of the second-order factor mean difference. Data were analyzed using correct and incorrect specifications of noninvariant loadings and intercepts. Results summarized across the 5,000 replications in each condition included Type I error rates and powers for the chi-square difference test and the Wald test of the second-order factor mean difference, estimation bias and efficiency for this latent mean difference, and means of the standardized root mean square residual (SRMR) and the root mean square error of approximation (RMSEA). When the model was correctly specified, no obvious estimation bias was observed; when the model was misspecified by constraining noninvariant loadings or intercepts to be equal, the latent mean difference was overestimated if the direction of the difference in loadings or intercepts of was consistent with the direction of the latent mean difference, and vice versa. Increasing the number of noninvariant loadings or intercepts resulted in larger estimation bias if these noninvariant loadings or intercepts were constrained to be equal. Power to detect the latent mean difference was influenced by estimation bias and the estimated variance of the difference in the second-order factor mean, in addition to sample size and effect size. Constraining more parameters to be equal between groups—even when unequal in the population—led to a decrease in the variance of the estimated latent mean difference, which increased power somewhat. Finally, RMSEA was very sensitive for detecting misspecification due to improper equality constraints in all conditions in the current scenario, including the nonzero latent mean difference, but SRMR did not increase as expected when noninvariant parameters were constrained. / Dissertation/Thesis / Masters Thesis Educational Psychology 2016

abstract: The study of subwavelength behavior of light and nanoscale lasing has broad potential applications in various forms of computation i.e. optical and quantum, as well as in energy engineering. Although this field has been under active research, there has been little work done on describing the behaviors of threshold and saturation. Particularly, how the gain-molecule behavior affects the lasing behavior has yet to be investigated. In this work, the interaction of surface-plasmon-polaritons (SPPs) and molecules is observed in lasing. Various phenomenologies are observed related to the appearance of the threshold and saturation regions. The lasing profile, as a visual delimiter of lasing threshold and saturation, is introduced and used to study various parametrical dependencies of lasing, including the number-density of molecules, the molecular thickness and the frequency detuning between the molecular transition frequency and the SPP resonant frequency. The molecular population distributions are studied in terminal and dynamical methods and are found to contain unexpected and theoretically challenging properties. Using an average dynamical analysis, the simulated spontaneous emission cascade can be clearly seen. Finally, theoretical derivations of simple 1D strands of dipoles are presented in both the exact and mean-field approximation, within the density matrix formalism. Some preliminary findings are presented, detailing the observed behaviors of some simple systems. / Dissertation/Thesis / Masters Thesis Chemical Engineering 2017

Submitted by Maike Costa (maiksebas@gmail.com) on 2017-07-03T13:42:30Z No. of bitstreams: 1 arquivototal.pdf: 2175297 bytes, checksum: 0d32244b68ce823204f52f4f1ca022de (MD5) / Made available in DSpace on 2017-07-03T13:42:30Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2175297 bytes, checksum: 0d32244b68ce823204f52f4f1ca022de (MD5) Previous issue date: 2017-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Genomic islands (GIs) are regions of the bacterial and archaeal genomes that were acquired through the phenomenon of horizontal transfer. Usually, these regions provide important adaptations to these organisms, such as antibiotic resistance and pathogenicity, whose effects can be harmful to other species. For these reasons, many computational methodologies have been proposed for their prediction, however, none of them are capable to precisely identify the whole repertoire of islands present in a given genomic sequence. Therefore, the development of new approaches that explore different aspects of these regions is timely, allowing the identification of those not known. In this paper, it is proposed a novel method for the identification of GIs, built based on mean shift clustering algorithm, with the automatic bandwidth calculation, necessary to its operation. Test results with genomic island inserted in bacterial genomes show that the method is capable of identifying these regions, with sensitivity rates above 99%. Tests performed with bacterial genomes with known GIs revealed the potential of the method for their identification and for the discovery of new island. The detailed study of the new islands content pointed the presence of typical GIs elements, confirming its effectiveness in the prediction of these regions. / Ilhas genômicas (IGs) são regiões do genoma de bactérias e arqueas adquiridas por meio do fenômeno da transferência horizontal. Frequentemente, essas regiões proporcionam importantes adaptações a esses organismos, como resistência a antibióticos e patogenicidade, cujos efeitos podem ser danosos a outras espécies. Por essa razão, diversas metodologias computacionais foram propostas para a sua predição, porém nenhuma capaz de identificar o repertório completo de ilhas presentes em uma determinada sequência genômica. Portanto, torna-se oportuno o desenvolvimento de novas abordagens que explorem diferentes aspectos dessas regiões, permitindo a identificação daquelas não conhecidas. Nesse trabalho, propõe-se um novo método para a identificação de IGs, construído com base no algoritmo de agrupamento mean shift, com o cálculo automático da largura de banda, indispensável para o seu funcionamento. Resultados dos testes com ilhas genômicas inseridas em genomas de bactérias mostram que o método é capaz de identificar essas regiões com taxas de acerto acima de 99%. Testes realizados com genomas de bactérias com IGs conhecidas revelaram o potencial do método para a sua identificação e para a descoberta de novas ilhas. O estudo detalhado do conteúdo das novas ilhas apontou a presença de elementos típicos de IGs, confirmando a eficácia do método na predição dessas regiões.

Made available in DSpace on 2015-05-14T12:14:21Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2227394 bytes, checksum: 05a68822cdf04f42c1f50d5c368cac63 (MD5) Previous issue date: 2011-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / wide range of pathogens are transmitted by a combination of horizontal and vertical transmission; among these are microsporodians, helminths, bacteria and viruses of plants and animals, including important human pathogens such as HIV, HTLV-1, cytomegalovirus, several hepatitis viruses and herpes simplex [Proc. R. Soc. Lond. B 260: 321-327]. In this work, the vertical parasite spreading from parent to offspring and horizontal transmission through infection in a population of moving individuals are discussed using a probabilistic cellular automata implemented on a square lattice. In our model, we generalize the automata proposed in [J. Phys. A : Math. Gen. 27: 1585-1597] to include the vertical transmission. The local rule consists of two subrules: the first one, applied synchronously, models infection, birth and death processes; the second, applied sequentially, describes the motion of individuals. In this model, endemic states may occur (susceptible and infected individuals coexisting) or a disease-free state (without infected). It is worth mentionins that a state in which the entire population becomes infective is possible in the case of perfect vertical transmission, i.e. infected parents give birth only to infected offspring. Moreover, the stability of these states may be analised using a mean-field approximation or grafically verified from the numerical simulations. / Uma ampla faixa de patógenos são propagados por uma combinação de transmissão horizontal e vertical, dentre os quais podemos destacar: microesporídeos, helmintos, bactérias, fungos e vírus de plantas e animais, incluindo importantes microorganismos parasitas de humanos como o HIV, HTLV-1, cytomegalovírus, vários tipos de hepatite e herpes simples [Proc. R. Soc. Lond. B 260: 321-327 (1995)]. Neste trabalho, a transmissão vertical (infecção do genitor para os filhos) e a transmissão horizontal (infecção por contágio) numa população de indivíduos em movimento são discutidos usando um autômato celular probabilístico implementado numa rede quadrada. Em tal modelo, generalizamos o autômato proposto em [J. Phys. A : Math. Gen. 27: 1585-1597 (1994)] para incluir a transmissão vertical. A regra local consiste de duas subregras: a primeira modela de maneira sincronizada os nascimentos, as mortes e as infecções; já a segunda, aplicada sequencialmente, descreve o movimento dos indivíduos. Neste modelo é possível um estado endêmico (suscetíveis coexistindo com infectados) ou um estado livre de doenças (sem infectados). Salienta-se que um estado em que toda a população torna-se infectada é possível no caso de transmissão vertical perfeita, i.e. pais infectados possuem apenas descendentes infectados. Inclusive, a estabilidade destes estados pode ser analizada na aproximação de campo médio para este modelo, ou verificada através dos gráficos dos resultados das simulações numéricas.

Resumo: A quantificação do vapor d'água integrado na atmosfera (IWV - Integrated Water Vapor), ao contrário de outras variáveis meteorológicas, é algo que ainda se apresenta como um grande desafio para as Ciências Atmosféricas. Diversos mecanismos, envolvendo diferentes técnicas, têm sido empregados e testados para esse fim em diferentes regiões do globo por pesquisa dores das mais variadas áreas da ciência. Essa tese apresenta uma contribuição a esse tema ao empregar receptores GPS (Global Positioning System) em bases terrestres, localizados no Brasil, envolvendo instituições de pesquisa na área de Geodésia e de Meteorologia. Os objetivos principais desse trabalho são validar os valores do IWV obtidos a partir das observações GPS e contribuir com a viabilização da utilização de redes ativas de receptores GPS, existentes atualmente e futuras, no monitoramento do IWV como suporte às atividades da Meteorologia e Climatologia no Brasil. Os resultados obtidos mostram que, com a efetivação desse processo, poderá ser obtida uma fonte adicional de informações da umidade para Previsão Numérica de Tempo (PNT). Além disso, é mostrado também que a alta resolução temporal dos valores do IWV obtidos a partir das observações GPS pode contribuir para a melhoria dos resultados gerados por outras técnicas empregadas na mesma tarefa. Em contrapartida, um modelo de PNT é utilizado para gerar previsões da influência da troposfera nos sinais GPS, visando beneficiar aplicações GPS em tempo real. Os resultados gerados nesse trabalho são frutos da sinergia entre as duas áreas envolvidas e mostram que, atualmente, há boas perspectivas para essa parceria no Brasil. / Abstract: Quantification of Integrated Water Vapor (IWV), unlike other meteorological variables, still represents a significant challenge to the Atmospheric Sciences. In this task several techniques using different mechanisms have been employed and tested in different regions of the planet. Many researchers from several areas of science have been involved in this process. This thesis presents a contribution to this theme, employing ground-based GPS receivers installed on Brazilian territory, involving Geodesy and Meteorology research institutes. The main aim of this work is to contribute in order to make enable the use of the existing networks of continuously operating GPS receivers, and those that will be installed in the future, in IWV monitoring to support meteorological and climatological activities in Brazil. The results generated show that in this process it is possible to obtain an additional source of humidity information for Numerical Weather Prediction (NWP). Furthermore, the prospect of using the ground-based GPS receivers to monitor atmospheric water vapor is promising because thehigh temporal resolution of IWV values from GPS observations can improve the results generated from other techniques employed in the same task. At the same time, a NWP model is applied to generate predictions of the atmosphere's influence over radiofrequency signals, to improve real time GPS applications. The results of this work stem from the synergy between the two areas of science involved. They show that the current outlook for this partnership in Brazil is good, and that both Meteorology and Geodesy will benefit. / Orientador: João Francisco Galera Monico / Coorientador: João Augusto Toledo Machado / Banca: José Antonio Aravequia / Banca: Paul J. de Jonge / Banca: José Tadeu Garcia Tommaselli / Banca: Paulo de Oliveira Camargo / Doutor

Made available in DSpace on 2015-05-15T11:46:15Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 577287 bytes, checksum: 05b66c45fbee6c87496fa2601f5736ea (MD5) Previous issue date: 2013-05-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / We study two types of Neumann problem related to Capillary problem and to the evolution of graphs under mean curvature flow in Riemannian manifolds endowed with a Killing vector field. In particular, we prove the existence of Killing graphs with prescribed mean curvature and prescribed boundary conditions. / Estudamos dois tipos de problemas relacionados com a Neumann problema capilar e à evolução dos gráficos sob fluxo de curvatura média em variedades Riemannianas dotados com um campo de vetores Killing. Em particular, provamos a existência de Matar gráficos prescrito com curvatura média e condições de contorno prescritas.

Submitted by Clebson Anjos (clebson.leandro54@gmail.com) on 2015-05-19T19:39:45Z No. of bitstreams: 1 arquivototal.pdf: 2901630 bytes, checksum: d49c78ad5c7d463bdc9e8f53c093d865 (MD5) / Approved for entry into archive by Clebson Anjos (clebson.leandro54@gmail.com) on 2015-05-19T19:39:55Z (GMT) No. of bitstreams: 1 arquivototal.pdf: 2901630 bytes, checksum: d49c78ad5c7d463bdc9e8f53c093d865 (MD5) / Made available in DSpace on 2015-05-19T19:39:55Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2901630 bytes, checksum: d49c78ad5c7d463bdc9e8f53c093d865 (MD5) Previous issue date: 2013-07-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work we present some constructions of the regular pentagon, the main one is a construction of Euclid found in his book The Elements. We also present some applications of this construction. / Neste trabalho, apresentamos algumas construções do pentágono regular, sendo a principal delas uma construção de Euclides encontrada no seu livro Os Elementos. Apresentamos, também, algumas aplicações desta construção.

Neste trabalho apresentamos condições suficientes para a existência de gráficos de curvatura média constante (CMC) com bordo em dois planos paralelos. Também são feitas estimativas para a altura de superfícies CMC com vetor normal orientado para fora limitadas por um cilindro ou horocilindro. / In this work we present su cient existence conditions for constant mean curvature (CMC) graphs with boundary in two parallel planes. We also make height estimates for outwards-oriented CMC surfaces bounded by a cylinder or horocylinder.

Este trabalho estuda o problema de seleção de carteiras de variância mínima com base em uma recente metodologia para otimização de carteiras com restrições nas normas das exposições brutas proposta por Fan, Zhang e Yu (2012). Para esse propósito, consideram-se diferentes estimadores da matriz de covariâncias condicional e incondicional. A grande contribuição deste artigo é de natureza empírica para o mercado de ações brasileiro. Avaliam-se índices de desempenho fora da amostra das carteiras construídas para um conjunto de 61 ações negociadas na Bolsa de Valores de São Paulo (BM&FBovespa). Os resultados mostraram que as restrições nas normas dos vetores de alocação (restrição de exposição bruta) geram ganhos substanciais em relação às carteiras restringidas para venda a descoberto, aumentando o retorno médio ajustado pelo risco e diminuindo o turnover dos portfólios. / This paper studies the problem of minimum variance portfolio selection based on a recent methodology for portfolio optimization restricting the allocation vector proposed by Fan, Zhang e Yu (2012). To achieve this, different conditional and inconditional covariance matrix estimators are considered. The great contribuition of this paper is one of empirical nature for the brazilian stock market. We evaluate out-of-sample performance indexes for the portfolios constructed for a set with 61 different sotcks traded in the São Paulo stock exchange (BM&FBovespa). The results show that the restrictions on the norms of the allocation vector generate substantial gains compared to the no short-sale portfolio, raising the average return adjusted by the risk and lowering the portfolio turnover.

The emission legislations and the new On Board Diagnostics (OBD) legislations are becoming more strict and making the demands on control and fault detection higher. One way to control and diagnose the engine is to use a control/diagnose strategy based on physical models and therefore better models are necessary. Also, to be competitive and meet the markets demand of higher power, longer durability and better fuel economy, the models needs to be improved continuously. In this thesis a mean value model of the intake system that predicts the charge air temperature has been developed. Three models of different complexity for the intercooler heat-exchanger have been investigated and validated with various results. The suggested intercooler heat-exchanger model is implemented in the mean value model of the intake system and the whole model is validated on three different data sets. The model predicts the intake manifold temperature with a maximum absolute error of 10.12 K.