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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

CODA CONSONANT CLUSTER PATTERNS IN THE ARABIC NAJDI DIALECT

Alkhonini, Omar Ahmed 01 May 2014 (has links)
This study examines the coda clusters in Classical Arabic and how Najdi speakers, modern inhabitants of the central area of Saudi Arabia, pronounce them. Fourteen Najdi participants were asked to read a list of thirty-one words that took into account falling, equal, and rising sonority clusters, consisting of obstruents, nasals, liquids, and glides. The instrument contained one, two, and three steps of sonority for each level of sonority (falling and rising) to determine the minimal sonority distance used in Najdi Arabic. Specifically, obstruent + nasal, nasal + liquid, and liquid + glide were included for falling sonority clusters of one step, obstruent + liquid and nasal + glide were used for falling sonority clusters of two steps, and only obstruent + glide for falling sonority clusters of three steps. To test the rising sonority clusters, the elements in the clusters were transposed for each combination; for example, instead of using obstruent + nasal, clusters of nasal + obstruent were considered. However, for equal sonority clusters, only obstruent + obstruent and nasal + nasal were examined. Obstruents were dealt with separately in the instrument at first to see whether they caused any difference in the results. The results showed that the subjects added epenthesis in the rising sonority clusters and equal sonority clusters containing sonorants. However, they did not add epenthesis in the falling sonority clusters or equal sonority clusters containing obstruents. Thus, no matter the distance in sonority between the two segments in the rising sonority clusters (one, two, or three steps), the participants always epenthesized them. In addition, no matter how many sonority steps there were between the two segments in the falling sonority clusters, the participants always produced them without modification. In case of equal sonority, when the two segments of the cluster were sonorants, the participants added epenthesis; however, when the two segments of the cluster were obstruents, the participants produced them without modification.
152

Uma análise dos vocoides altos em português brasileiro : relações entre silabificação e atribuição do acento

Simioni, Taíse January 2011 (has links)
Neste trabalho, buscamos observar como os vocoides altos se comportam, no que diz respeito à silabificação e à atribuição do acento, em português brasileiro (PB). O termo “vocoide” é aqui empregado para designar um segmento subjacente que pode se realizar como vogal ou como glide. Nosso objetivo, então, é o de verificar em que contextos a realização se dará com uma ou com outro. Para a análise que tem como pressuposto teórico a Teoria de Otimidade (Prince e Smolensky (1993), McCarthy e Prince (1993b)), tomamos como ponto de partida as hipóteses de que o glide pós-vocálico localiza-se na coda silábica, enquanto o glide pré-vocálico forma núcleo complexo com a vogal seguinte. O principal argumento para a primeira hipótese é o fato de que o glide não coocorre com um (outro) segmento em coda. Fundamentando a segunda hipótese, há o fato de que o glide pré-vocálico possui um papel a desempenhar na atribuição do acento, uma vez que não existem palavras em PB nas quais o acento “pula” uma sílaba constituída por ditongo crescente na penúltima posição (*ídioma). Em uma análise não derivacional, não é possível interpretar tal ausência como consequência do fato de que, em uma etapa anterior de silabificação, o vocoide alto ocupa a posição de núcleo, o que significa que o acento não pode incidir em uma sílaba à sua esquerda, pois estaria sendo violada a restrição da “janela de três sílabas”. Propomos, então, um ranqueamento que dá conta das diferentes estruturas silábicas de vogal mais glide pós-vocálico e de glide pré-vocálico mais vogal. No que diz respeito à atribuição do acento, foi possível observar que, de maneira geral, o vocoide alto só receberá acento se for acentuado no input. Se o acento não estiver presente no input ou se outro segmento receber acento no input, haverá uma preferência pela realização do vocoide alto como glide, uma vez que tal realização permite a satisfação simultânea das restrições relativas à silabificação e à atribuição do acento. / In this work, we aim to analyze the way high vocoids behave in relation to syllabification and stress assignment in Brazilian Portuguese (BP). The term “vocoid” is used here to express a subjacent segment that can surface as vowel or glide. Our objective is to verify in which contexts will surface one or the other. Based on Optimality Theory (Prince and Smolensky (1993), McCarthy and Prince (1993b)), we take as starting point the hypothesis that the postvocalic glide is placed in the syllabic coda whereas the prevocalic glide forms a complex nucleus with the following vowel. In relation to the first hypothesis, the main argument refers to the fact that the glide does not co-occur with another coda segment. Concerning the second hypothesis, our argument refers to the fact that the prevocalic glide has to play a role in the stress assignment, since there are not words in BP in which the stress “jumps” a syllable constituted by rising diphthong in the penultimate position (*ídioma). In a non-derivational analysis, it is not possible to interpret this absence as a consequence of an anterior stage of syllabification, where the high vocoid was placed in the nucleus position, and stress placement on a syllable on its left would mean a “three syllable window” violation. Therefore, we propose a ranking that deals with the different syllabic structures of vowel plus postvocalic glide and prevocalic glide plus vowel. In relation to stress assignment, in a general way, we observed that the high vocoid will be stressed only if it is stressed in the input. If the stress is not present in the input or if other segment is stressed in the input, there will be a preference for the realization of a high vocoid as glide, since this realization allows a simultaneous satisfaction of the constraints relating to syllabification and to stress assignment.
153

Condições sequenciais de otimalidade / Sequential optimality conditions

Haeser, Gabriel 09 April 2009 (has links)
Orientador: Jose Mario Martinez / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-08-14T02:27:22Z (GMT). No. of bitstreams: 1 Haeser_Gabriel_D.pdf: 1980596 bytes, checksum: 34e962c907bf0b544d52deba5e4555e6 (MD5) Previous issue date: 2009 / Resumo: Estudamos as condições de otimalidade provenientes dos algoritmos de penalidade externa, penalidade interna, penalidade interna-externa e restauração inexata, e mostramos relações com a CPLD, uma nova condição de qualificação estritamente mais fraca que a condição de Mangasarian-Fromovitz e a condição de posto constante de Janin. Estendemos o resultado do clássico Lema de Carathéodory, onde mostramos um limitante para o tamanho dos novos multiplicadores. Apresentamos novas condições de otimalidade relacionadas à condição AGP (Approximate Gradient Projection). Quando há um conjunto extra de restrições lineares, definimos uma condição do tipo AGP e provamos relações com a CPLD e as equações KKT. Resultados similares são obtidos quando há um conjunto extra de restrições convexas. Mostramos também algumas generalizações e relações com um algoritmo de restauração inexata. / Abstract: We study optimality conditions generated by the external penalty, internal penalty, internal-external penalty and inexact restoration algorithms, and we show relations with the CPLD, a new constraint qualification strictly weaker than the Mangasarian-Fromovitz condition and the constant rank condition of Janin. We extend the result of the classical Carathéodory's Lemma, where we show a bound for the size of the new multipliers. We present new optimality conditions related to the Approximate Gradient Projection condition (AGP). When there is an extra set of linear constraints, we define an AGP type condition and prove relations with CPLD and KKT conditions. Similar results are obtained when there is an extra set of convex constraints. We provide some further generalizations and relations to an inexact restoration algorithm. / Doutorado / Otimização / Doutor em Matemática Aplicada
154

Condições suficientes de otimalidade para o problema de controle de sistemas lineares estocásticos / Sufficient optimality conditions for the control problem of linear stochastic systems

Madeira, Diego de Sousa 20 August 2018 (has links)
Orientador: João Bosco Ribeiro do Val / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-20T16:10:11Z (GMT). No. of bitstreams: 1 Madeira_DiegodeSousa_M.pdf: 382775 bytes, checksum: d75575b4a57a5bb98739210edef9b5c7 (MD5) Previous issue date: 2012 / Resumo: As principais contribuições deste trabalho são a obtenção de condições necessárias e suficientes de otimalidade para o problema de controle de sistemas lineares determinísticos discretos e para certas classes de sistemas lineares estocásticos. Adotamos o método de controle por realimentação de saída, um horizonte de controle finito e um funcional de custo quadrático nas variáveis de estado e de controle. O problema determinístico é solucionado por completo, ou seja, provamos que para qualquer sistema MIMO as condições necessárias de otimalidade são também suficientes. Para tanto, uma versão do Princípio do Máximo Discreto é utilizada. Além disso, analisamos o caso estocástico com ruído aditivo e provamos que o princípio do máximo discreto fornece as condições necessárias de otimalidade para o problema, embora não garanta suficiência. Por fim, em um cenário particular com apenas dois estágios, empregamos uma técnica de parametrização do funcional de custo associado ao sistema linear estocástico com ruído aditivo e provamos que, no caso dos sistemas SISO com matrizes C (saída) e B (entrada) tais que CB = 0, as condições necessárias de otimalidade são também suficientes. Provamos que o mesmo também é válido para a classe dos Sistemas Lineares com Saltos Markovianos (SLSM), no contexto especificado. Com o objetivo de ilustrar numericamente os resultados teóricos obtidos, alguns exemplos numéricos são fornecidos / Abstract: The main contributions of this work are that the necessary and sufficient optimality conditions for the control problem of discrete linear deterministic systems and some classes of linear stochastic systems are obtained. We adopted the output feedback control method, a finite horizon control and a cost function that is quadratic in the state and control vectors. The deterministic problem is completely solved, that is, we prove that for any MIMO system the necessary optimality conditions are also sufficient. To do so, a formulation of the Discrete Maximum Principle is used. Furthermore, we analyze the stochastic case with additive noise and prove that the discrete maximum principle provides the necessary optimality conditions, though they are not sufficient. Finally, in a particular two-stage scenario, we apply a parametrization technique of the cost function associated with the linear stochastic system with additive noise and prove that, for SISO systems with orthogonal matrices C (output) and B (input) so that CB = 0, the necessary optimality conditions are sufficient too. We prove that under the underlined context the previous statement is also valid in the case of the Markov Jump Linear Systems (MJLS). In order to illustrate the theoretical results obtained, some numerical examples are given / Mestrado / Automação / Mestre em Engenharia Elétrica
155

A metrical analysis of Blackfoot nominal accent in optimality theory

Kaneko, Ikuyo 05 1900 (has links)
Blackfoot (Siksika), an Algonquian language spoken in Southern Alberta and in Northwestern Montana, is claimed to have a pitch-accent system (Frantz 1991). However, no complete analysis of the Blackfoot word accent system is available in the literature. This thesis examines Blackfoot nominal accent by means of metrical analysis (Halle and Vergnaud 1987) in Optimality Theory (OT) (Prince and Smolensky 1993). All of the data in this thesis are elicited from native speakers of Blackfoot. Regardless of noun type, every word contains one and only one pitch peak. Bare nouns (mono-morphemic nouns) and relational nouns (dependent nouns) show that Blackfoot has a mixed predictable and lexical accent system. Accent is quantity-sensitive, i.e. a heavy syllable attracts accent, while in nouns which contain no heavy syllable or more than one heavy syllable, it is lexically specified. An interesting contrast is found in long vowels - they contrast a high-level pitch, a falling pitch, and a rising pitch. Derived nouns (compounds) demonstrate four kinds of accent patterns, depending on the status (free vs. bound) and the accentual property (accented vs. unaccented) of morphemes. The leftmost accent of the compound members is retained, but the accent shifts to the juncture of them if it is word-final. If compound members are unaccented, the accent is assigned to word-final position by default. Speaker variation also occurs. One speaker systematically changes vowel length depending on the type of accented syllable, while the other speaker shows a wide variety of accent patterns. This thesis concludes that all the accent patterns can be accounted for by a single ranking of constraints in an OT analysis, in spite of the fact that the accent system is both lexical and predictable. Addition of constraints is needed specifically for compounds! Speaker variation is accounted for by reranking the same set of constraints. Priority is given to constraints that refer to the predictable accent in the grammar of one speaker. The lexical information is more respected in the other speaker's grammar. In addition to the analysis of general pitch-accent patterns, four types of irregular patterns are examined. The conclusions reached in this thesis demonstrate that the accent system interacts with other phonological properties of Blackfoot. / Arts, Faculty of / Linguistics, Department of / Graduate
156

Codon bias confers stability to human mRNAs / コドンバイアスがヒトmRNAを安定化する

Hia, Fabian 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22356号 / 医博第4597号 / 新制||医||1042(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 萩原 正敏, 教授 岩田 想, 教授 齊藤 博英 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
157

Multi-criteria decision making using reinforcement learning and its application to food, energy, and water systems (FEWS) problem

Aishwarya Vikram Deshpande (11819114) 20 December 2021 (has links)
<p>Multi-criteria decision making (MCDM) methods have evolved over the past several decades. In today’s world with rapidly growing industries, MCDM has proven to be significant in many application areas. In this study, a decision-making model is devised using reinforcement learning to carry out multi-criteria optimization problems. Learning automata algorithm is used to identify an optimal solution in the presence of single and multiple environments (criteria) using pareto optimality. The application of this model is also discussed, where the model provides an optimal solution to the food, energy, and water systems (FEWS) problem.</p>
158

A formação de adjetivos e processos morfofonológicos no Português Arcaico : uma análise segundo a Teoria da Otimalidade /

Mielo, Tamires Costa e Silva. January 2018 (has links)
Orientador: Daniel Soares da Costa / Banca: Luiz Carlos Cagliari / Banca: Juliana Bertucci Barbosa / Resumo: O presente trabalho tem como objetivo analisar, por meio da Teoria da Otimalidade, os processos morfofonológicos desencadeados pela formação de adjetivos no Português Arcaico. Para tal, foi feito o levantamento de 269 adjetivos, retirados das 100 primeiras Cantigas de Santa Maria, documento representativo do período do Português Arcaico. Depois de selecionados, os adjetivos foram divididos em primitivos e derivados, de modo que os derivados totalizaram 191 vocábulos. A partir daí, foi feita, primeiramente, uma análise morfológica, verificando quais são os tipos de formação de adjetivos existentes no Português Arcaico, sendo a sufixação o mais recorrente entre eles. Em seguida, verificamos também que o sufixo -do é o mais produtivo de adjetivos nesse período da língua, seguido do sufixo -oso, também bastante produtivo. Em um segundo momento, foi feita a análise fonológica dos vocábulos que sofreram algum tipo de adaptação morfofonológica em seu processo de formação segundo a Teoria da Otimalidade. Essa análise mostrou que a restrição que proíbe formação de hiato é alta na hierarquia das restrições do Português Arcaico, fato que explica o grande número de supressão ou queda de vogais temáticas da base na formação de novos vocábulos. Ademais, tentamos encontrar uma hierarquia de restrições que desse conta do maior número de vocábulos e de adaptações sofridas por eles. / Abstract: This paperwork aims to analyze, through the Optimality Theory, the morphophonological processes unleashed by the formation of adjectives in Ancient Portuguese. To do so, 269 were collected from the first 100 Cantigas de Santa Maria, important document from the Ancient Portuguese period. After collected, the adjectives were divided between primitive and derived. The derived adjectives totalized 191. After that, a morphological analysis was done, to verify what are the existing adjectives formation processes in Ancient Portuguese, being the suffixation the most common among them. We verified next that the suffix -do is the most productive of adjectives in this period, followed by suffix -oso, also very productive. Thereafter, we did the phonological analysis in the words that suffered some kind of morphophonological adaptation in its formation process, through the Optimality Theory. This analysis showed that the constraint that forbids the hiatus formation is high in the ranking of constraints in Ancient Portuguese, what explains the great number of theme vowels suppression in the base form during the formation of new words. Furthermore, we tried to find a ranking of constraints valid for the greatest number of adjectives and of adaptations suffered by them / Mestre
159

Sharp oracle inequalities in aggregation and shape restricted regression / Inégalités d'oracle exactes pour l'agrégation et la régression sous contrainte de forme

Bellec, Pierre C. 28 June 2016 (has links)
Deux sujet sont traités dans cette thèse: l'agrégation d'estimateurs et la régression sous contrainte de formes.La régression sous contrainte de forme étudie le problème de régression (trouver la fonction qui représente un nuage de points),avec la contrainte que la fonction en question possède une forme spécifique.Par exemple, cette fonction peut être croissante ou convexe: ces deux contraintes de forme sont les plus étudiées. Nous étudions en particulier deux estimateurs: un estimateur basé sur des méthodes d'agrégation et l'estimateur des moindres carrés avec une contrainte de forme convexe. Des inégalités d'oracle sont obtenues, et nous construisons aussi des intervalles de confiance honnêtes et adaptatifs.L'agrégation d'estimateurs est le problème suivant. Lorsque plusieurs méthodes sont proposées pour le même problème statistique, comment construire une nouvelle méthode qui soit aussi performante que la meilleure parmi les méthodes proposées? Nous étudierons ce problème dans trois contextes: l'agrégation d'estimateurs de densité, l'agrégation d'estimateurs affines et l'aggrégation sur le chemin de régularisation du Lasso. / This PhD thesis studies two fields of Statistics: Aggregation of estimatorsand shape constrained regression.Shape constrained regression studies the regression problem (find a function that approximates well a set of points) with an underlying shape constraint, that is, the function must have a specific "shape". For instance, this function could be nondecreasing of convex: These two shape examples are the most studied. We study two estimators: an estimator based on aggregation methods and the Least Squares estimator with a convex shape constraint. Oracle inequalities are obtained for both estimators, and we construct confidence sets that are adaptive and honest.Aggregation of estimators studies the following problem. If several methods are proposed for the same task, how to construct a new method that mimics the best method among the proposed methods? We will study these problems in three settings: aggregation of density estimators, aggregation of affine estimators and aggregation on the regularization path of the Lasso.
160

Experimental Evaluation of Error bounds for the Stochastic Shortest Path Problem

Abdoulahi, Ibrahim 14 December 2013 (has links)
A stochastic shortest path (SSP) problem is an undiscounted Markov decision process with an absorbing and zero-cost target state, where the objective is to reach the target state with minimum expected cost. This problem provides a foundation for algorithms for decision-theoretic planning and probabilistic model checking, among other applications. This thesis describes an implementation and evaluation of recently developed error bounds for SSP problems. The bounds can be used in a test for convergence of iterative dynamic programming algorithms for solving SSP problems, as well as in action elimination procedures that can accelerate convergence by excluding provably suboptimal actions that do not need to be re-evaluated each iteration. The techniques are shown to be effective for both decision-theoretic planning and probabilistic model checking.

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