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A fundamental challenge in target detection in hyperspectral imagery is spectral variability. In target detection applications, we are provided with a pure target signature; we do not have a collection of samples that characterize the spectral variability of the target. Another problem is that the performance of stochastic detection algorithms such as the spectral matched filter can be detrimentally affected by the assumptions of multivariate normality of the data, which are often violated in practical situations. We address the challenge of lack of training samples by creating two models to characterize the target class spectral variability --the first model makes no assumptions regarding inter-band correlation, while the second model uses a first-order Markovbased scheme to exploit correlation between bands. Using these models, we present two techniques for meeting these challenges-the kernel-based support vector data description (SVDD) and spectral fringe-adjusted joint transform correlation (SFJTC). We have developed an algorithm that uses the kernel-based SVDD for use in full-pixel target detection scenarios. We have addressed optimization of the SVDD kernel-width parameter using the golden-section search algorithm for unconstrained optimization. We investigated a proper number of signatures N to generate for the SVDD target class and found that only a small number of training samples is required relative to the dimensionality (number of bands). We have extended decision-level fusion techniques using the majority vote rule for the purpose of alleviating the problem of selecting a proper value of s 2 for either of our target variability models. We have shown that heavy spectral variability may cause SFJTC-based detection to suffer and have addressed this by developing an algorithm that selects an optimal combination of the discrete wavelet transform (DWT) coefficients of the signatures for use as features for detection. For most scenarios, our results show that our SVDD-based detection scheme provides low false positive rates while maintaining higher true positive rates than popular stochastic detection algorithms. Our results also show that our SFJTC-based detection scheme using the DWT coefficients can yield significant detection improvement compared to use of SFJTC using the original signatures and traditional stochastic and deterministic algorithms.

In 1988, Owen introduced empirical likelihood as a nonparametric method for constructing confidence intervals and regions. Since then, empirical likelihood has been studied extensively in the literature due to its generality and effectiveness. It is well known that empirical likelihood has several attractive advantages comparing to its competitors such as bootstrap: determining the shape of confidence regions automatically using only the data; straightforwardly incorporating side information expressed through constraints; being Bartlett correctable. The main part of this thesis extends the empirical likelihood method to several interesting and important statistical inference situations. This thesis has four components. The first component (Chapter II) proposes a smoothed jackknife empirical likelihood method to construct confidence intervals for the receiver operating characteristic (ROC) curve in order to overcome the computational difficulty when we have nonlinear constrains in the maximization problem. The second component (Chapter III and IV) proposes smoothed empirical likelihood methods to obtain interval estimation for the conditional Value-at-Risk with the volatility model being an ARCH/GARCH model and a nonparametric regression respectively, which have applications in financial risk management. The third component(Chapter V) derives the empirical likelihood for the intermediate quantiles, which plays an important role in the statistics of extremes. Finally, the fourth component (Chapter VI and VII) presents two additional results: in Chapter VI, we present an interesting result by showing that, when the third moment is infinity, we may prefer the Student's t-statistic to the sample mean standardized by the true standard deviation; in Chapter VII, we present a method for testing a subset of parameters for a given parametric model of stationary processes.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-16T14:58:29Z No. of bitstreams: 2 Dissertação - Ali Ahmad Smidi - 2015.pdf: 3816502 bytes, checksum: 2de9ac5a926f797906194c9463dfaeec (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-16T15:01:13Z (GMT) No. of bitstreams: 2 Dissertação - Ali Ahmad Smidi - 2015.pdf: 3816502 bytes, checksum: 2de9ac5a926f797906194c9463dfaeec (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-16T15:01:13Z (GMT). No. of bitstreams: 2 Dissertação - Ali Ahmad Smidi - 2015.pdf: 3816502 bytes, checksum: 2de9ac5a926f797906194c9463dfaeec (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-06-30 / In thisstudy,wesoughttopresentanintroductiontonumericaltechniquesaimedto optimize accessibleelementaryproblemstothestudentsofsecondandthirdyearofhigh school.TheoptimizationtechniquesdiscussedinthisworkweretheFibonacciandthe Golden Sectionmethods.Theworkpresentsanddoesmathematicaldescriptionofsuch techniques,fromaninitialknowledgeandbuildingmethodsinquestion.Inaddressinga real problem,weattemptedtointroducetheinterpretationandmathematicalmodeling of theproblemaswellasitssolutionsanalyticallyandnumerically,usingsoftwares simple touse.Inthisregard,itcanbestatedthatthepresentworkprovidesdidactical approachofmainunimodaloptimizationtechniquestoreduceuncertaintyinterval. / No presentetrabalho,buscou-seapresentarumainiciaçãoàstécnicasnuméricasvol- tadas paraaotimizaçãodeproblemaselementaresacessíveisaosalunosdosegundoe terceiro anodoensinomédio.AstécnicasdeotimizaçãotrabalhadasforamosMétodos de buscadeFibonacciedaSeçãoÁurea.Otrabalhoapresentaedetalhamatemati- camentetaistécnicas,alémdesemprepartirdeumconhecimentoinicialeconstruir os métodosemquestão.Aoabordarumproblemareal,buscou-seintroduzirain- terpretação eamodelagemmatemáticadoproblema,bemcomosuasolução,tanto analítica quantonumérica,utilizandováriossoftwarescomputacionaisdesimplesuti- lização. Nestesentido,pode-seafirmarqueopresentetrabalhotrazumaabordagem didática dasprincipaistécnicasdeotimizaçãounimodalporreduçãodeintervalosde incerteza.

Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-05-11T20:16:35Z No. of bitstreams: 2 Dissertação - Adriana Carvalho Rosa - 2016.pdf: 2874411 bytes, checksum: 9e7584f85cdb29badab59c80b696a8f7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-05-12T10:39:24Z (GMT) No. of bitstreams: 2 Dissertação - Adriana Carvalho Rosa - 2016.pdf: 2874411 bytes, checksum: 9e7584f85cdb29badab59c80b696a8f7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-05-12T10:39:24Z (GMT). No. of bitstreams: 2 Dissertação - Adriana Carvalho Rosa - 2016.pdf: 2874411 bytes, checksum: 9e7584f85cdb29badab59c80b696a8f7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2016-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Technological developments, it increases the interest in techniques that facilitate the understanding of phenomena not previously studied. This is fairly evident when it comes to Engineering and Applied Sciences because with more efficient computers, it is now possible solve problems increasingly complex and difficult to solve. As well when it comes to education, it is possible to realize the great advancement of technology, both as teaching resources in their own daily life of teachers and students, increasingly have access to tools that improve academic development. In this regard, this work shows techniques for solving basic optimization problems that can be presented to students of Basic Education with minimal knowledge about functions. Thus, we present a study about the Golden Section and Genetic Algorithms techniques. Shown examples of possible applications of techniques, with detailed solutions to facilitate understanding of the proposed theme. In this sense, one can say than the present work provides an educational approach to optimization techniques and, is a challenging work with regard to the use of new technologies in education. / Com o avanço tecnológico, é crescente o interesse por técnicas que facilitem a compreensão de fenômenos antes não estudados. Isto é bastante evidente quando se fala em Ciências Aplicadas e Engenharias, pois com computadores cada vez mais eficientes, hoje é possível resolver problemas cada vez mais complexos e de difícil solução. Também no que tange a parte educacional, é possível perceber o grande avanço da tecnologia, tanto nos recursos didáticos quanto no próprio cotidiano de professores e alunos que, possuem cada vez mais acesso a ferramentas que melhoram o desenvolvimento acadêmico. Neste sentido, este trabalho mostra técnicas para a resolução de problemas elementares de otimização que podem ser apresentados para alunos do Ensino Básico com conhecimento mínimo sobre funções. Assim, é feito um estudo acerca das técnicas: Seção Áurea e Algoritmos Genéticos. São mostrados exemplos de possíveis aplicações das técnicas, com resoluções detalhadas para facilitar a compreensão do tema proposto. Neste sentido, pode-se afirmar que o presente trabalho traz uma abordagem didática dessas técnicas de otimização, visando ser um motivador no que diz respeito à utilização de novas tecnologias no ensino.

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O crescimento da utilização de sistemas de reconhecimento no mundo contemporâneo exige processos de detecção cada vez mais robustos e ágeis. Aplicáveis desde sistemas de teleconferência empresarial até mecanismos de segurança e vigilância, a detecção e o reconhecimento de pessoas tornaram-se uma constante. Na tentativa de buscar caminhos alternativos, tanto para os problemas de detecção, quanto para os de reconhecimento, este trabalho propõe a utilização de medidas biométricas, mensuradas em imagens digitalizadas de faces humanas. A partir do estudo de tais medidas, torna-se possível a verificação de proporções existentes na face, especialmente a proporção divina, podendo constituir, no futuro, a base para algoritmos de detecção e/ou reconhecimento que usufruam das informações trazidas por tais proporções. Diante de uma reduzida quantidade de publicações no meio científico que utilizam a proporção divina como meio de detecção e/ou reconhecimento em processamento de imagens, esta investigação vem contribuir com alguns passos nessa direção / The increase of recognition systems in the contemporary world has demanded robust and agile detection processes. From teleconference systems to security and monitoring mechanisms, the detection and recognition of people have became constantly used and applied. In attempt to search for alternative ways to solve both detection and recognition problems, this work proposes the utilization of biometric measures, taken in digital image of human faces. From the study of such measures, it’s possible to verify face proportions, especially the divine proportion, which could allows, in the future, to implement the detection and/or recognition algorithms that utilize such proportions. Due to small amount of scientific publications that use the divine proportion as a way of detection and/or recognition in image processing, this investigation contributes with some steps in this direction

Made available in DSpace on 2016-04-27T16:56:59Z (GMT). No. of bitstreams: 1 dissertacao_olga_corbo.pdf: 11888785 bytes, checksum: 9fd54776e71e1d194c1bd940375f91fc (MD5) Previous issue date: 2005-08-16 / We have conducted this study to contribute to education of future teachers, by proposing the use of golden section as a context to explore the notion of incommensurable magnitudes. We have based our study on the notion of jeux de cadres , introduced by Douady (1986) in Mathematics Didactic, and used the Didactic Engineering research methodology. Our research was developed on the following hypothesis: a teaching sequence about the golden section which favors an interaction among different knowledge domains can advance the comprehension and/or development of the notion of incommensurability of straight line segments . For this study, we have attempted to determine if the process of successive divisions based on Euclids algorithm helped foster the development of the notion of incommensurability of straight line segments in the future teachers. Furthermore, we verified whether they used the jeux de cadres to solve some problems presented in the sequence and how it contributed to develop the notion of golden rectangle and the notion of incommensurable straight line segments. Finally, we determined if they have established a relationship between the golden rectangle characteristics and the notion of incommensurability of straight line segments, by offering a proof of the incommensurability of the sides of the golden rectangle. The results seem to indicate some progress in relation to the answers provided in the pre-test, which allows us to conclude that the golden section can be a favorable context for the comprehension and/or development of the notion of incommensurable straight line segments. The examination of the students performance have also shown that the sequence can promote an interaction among different knowledge domains, allowing a connection between certain geometric constructions and irrational numbers. At the end, we discuss some limitations observed during the development of this study, whose analysis can serve as a starting point for new investigations on the same theme. / O presente estudo foi realizado com o objetivo de contribuir para a formação inicial de professores de Matemática, propondo a utilização da seção áurea como contexto para explorar a noção de incomensurabilidade de segmentos de reta. Tomando como referencial teórico a noção de jogos de quadros , introduzida por Douady (1986) na Didática da Matemática e usando a metodologia de pesquisa denominada Engenharia Didática, desenvolvemos nosso trabalho com base na hipótese de que uma seqüência de ensino sobre a seção áurea, cuja realização favoreça a articulação entre quadros distintos de conhecimentos, pode propiciar a compreensão e/ou desenvolvimento da noção de incomensurabilidade de segmentos de reta . Por este estudo, examinamos se o processo das divisões sucessivas baseado no algoritmo de Euclides propiciou aos sujeitos de nossa pesquisa o desenvolvimento da noção de incomensurabilidade de segmentos de reta. Analisamos, ainda se os participantes recorriam à mudança de quadros para a resolução de algumas das situações apresentadas na seqüência e de que forma essa estratégia contribuiu para introduzir a noção de retângulo áureo e a noção de incomensurabilidade de segmentos de reta. Finalmente, examinamos se estabeleciam uma relação entre as características do retângulo áureo e a noção de incomensurabilidade de segmentos de reta, por meio da elaboração de uma justificativa de que os lados do retângulo áureo são segmentos incomensuráveis entre si. Os resultados indicam que houve um avanço em relação às respostas apresentadas no pré-teste, permitindo-nos concluir que a seção áurea pode ser um contexto favorável à compreensão e/ou desenvolvimento da noção de segmentos incomensuráveis. O exame do desempenho dos estudantes revelou também que a seqüência desenvolvida pode favorecer a inter-relação entre quadros distintos de conhecimentos, possibilitando que seja estabelecido um elo de ligação entre determinadas construções geométricas e números irracionais. Nas considerações finais, são discutidas as limitações observadas durante a realização deste trabalho, cuja análise poderá servir como ponto de partida para novas investigações sobre o mesmo tema.