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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.
31

客語打類、忍類及促類動詞中動力學之體現 / Force-Dynamic Manifestations of Verbs of Hitting, Refraining, and Urging in Hakka

強舒媺, Shu-mei Chiang Unknown Date (has links)
本論文「客語打類、忍類及促類動詞中動力學之體現」從物理學中之動力學觀點來審視語言之現象,以Lai (2000)針對客語打類動詞詞彙化類型之研究以及Gao (2001), Gao & Cheng (2002)針對中文與英語中肢體接觸類動詞之研究為基礎,並進一步修正及採用Talmy (2000a)所提出之動力學架構來加以分析客語打類、忍類及促類三類近義動詞。客語之打類動詞涉及內在心理意圖與外在肢體接觸,亦即同時牽涉到心理層面與肢體層面中「力」的作用,忍類動詞中「力」的衝突發生於內在心理層面,亦即本我與自我之間產生衝突,而促類動詞則表現出交互心理層面中「力」的相對關係,亦即藉由溝通等方式與他人產生「力」的對抗。因此,本論文藉由分析此三類動詞,將得已呈現心理肢體(psychophysical),內在心理(intrapsychological)以及交互心理(interpsychological)三個不同層面中動力學之體現,並能夠進一步檢視語意內涵「力」與此三類動詞之句法表現間之相互關係。 / Based on Lai’s (2000) study of verbs of hitting in Hakka and Gao’s (2001) and Gao & Cheng’s (2002) studies of verbs of physical action by impact in English and Mandarin Chinese, this study modifies the force-dynamic model proposed by Talmy (2000a) to analyze Hakka hitting verbs in psychophysical domain, Hakka refraining verbs in intrapsychological domain, and Hakka urging verbs in interpsychological domain. The analysis proposes that two force-dynamic patterns can be generalized from these three groups of verbs, one ONSET CAUSATION pattern, and the other ONSET DESPITE pattern. Moreover, the correlation between the semantic component FORCE and the syntactic manifestation has been examined. This force-dynamic opposition is manifested in syntax as demonstrated by resultative complements, BUN-constructions, LAU-constructions, the potential mode and verb-copying constructions along with the adverbs of duration. In addition, the confirmation of the speaker’s expectation can be achieved by adverbs of evaluation and adverbs of justification. The well-formedness of these syntactic structures and the felicity of the usage of the adverbs depend heavily on the interaction of the Antagonist’s force and the Agonist’s force.
32

Cadeias de Markov Quânticas / Quantum Markov Chains

Raqueline Azevedo Medeiros Santos 05 March 2010 (has links)
Em Ciência da Computação, os caminhos aleatórios são utilizados em algoritmos randômicos, especialmente em algoritmos de busca, quando desejamos encontrar um estado marcado numa cadeia de Markov. Nesse tipo de algoritmo é interessante estudar o Tempo de Alcance, que está associado a sua complexidade computacional. Nesse contexto, descrevemos a teoria clássica de cadeias de Markov e caminhos aleatórios, assim como o seu análogo quântico. Dessa forma, definimos o Tempo de Alcance sob o escopo das cadeias de Markov quânticas. Além disso, expressões analíticas calculadas para o tempo de Alcance quântico e para a probabilidade de encontrarmos um elemento marcado num grafo completo são apresentadas como os novos resultados dessa dissertação. / In Computer Science, random walks are used in randomized algorithms, specially in search algorithms, where we desire to find a marked state in a Markov chain.In this type of algorithm,it is interesting to study the Hitting Time, which is associated to its computational complexity. In this context, we describe the classical theory of Markov chains and random walks,as well as their quantum analogue.In this way,we define the Hitting Time under the scope of quantum Markov chains. Moreover, analytical expressions calculated for the quantum Hitting Time and for the probability of finding a marked element on the complete graph are presented as the new results of this dissertation.
33

Connecting hitting sets and hitting paths in graphs

Camby, Eglantine 30 June 2015 (has links)
Dans cette thèse, nous étudions les aspects structurels et algorithmiques de différents problèmes de théorie des graphes. Rappelons qu’un graphe est un ensemble de sommets éventuellement reliés par des arêtes. Deux sommets sont adjacents s’ils sont reliés par une arête.<p>Tout d’abord, nous considérons les deux problèmes suivants :le problème de vertex cover et celui de dominating set, deux cas particuliers du problème de hitting set. Un vertex cover est un ensemble de sommets qui rencontrent toutes les arêtes alors qu’un dominating set est un ensemble X de sommets tel que chaque sommet n’appartenant pas à X est adjacent à un sommet de X. La version connexe de ces problèmes demande que les sommets choisis forment un sous-graphe connexe. Pour les deux problèmes précédents, nous examinons le prix de la connexité, défini comme étant le rapport entre la taille minimum d’un ensemble répondant à la version connexe du problème et celle d’un ensemble du problème originel. Nous prouvons la difficulté du calcul du prix de la connexité d’un graphe. Cependant, lorsqu’on exige que le prix de la connexité d’un graphe ainsi que de tous ses sous-graphes induits soit borné par une constante fixée, la situation change complètement. En effet, pour les problèmes de vertex cover et de dominating set, nous avons pu caractériser ces classes de graphes pour de petites constantes.<p>Ensuite, nous caractérisons en termes de dominating sets connexes les graphes Pk- free, graphes n’ayant pas de sous-graphes induits isomorphes à un chemin sur k sommets. Beaucoup de problèmes sur les graphes sont étudiés lorsqu’ils sont restreints à cette classe de graphes. De plus, nous appliquons cette caractérisation à la 2-coloration dans les hypergraphes. Pour certains hypergraphes, nous prouvons que ce problème peut être résolu en temps polynomial.<p>Finalement, nous travaillons sur le problème de Pk-hitting set. Un Pk-hitting set est un ensemble de sommets qui rencontrent tous les chemins sur k sommets. Nous développons un algorithme d’approximation avec un facteur de performance de 3. Notre algorithme, basé sur la méthode primal-dual, fournit un Pk-hitting set dont la taille est au plus 3 fois la taille minimum d’un Pk-hitting set. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
34

"Un parent est battu" : les adolescents qui frappent leurs parents / "A parent is beaten" : adolescents who are hitting their parents / "Un progenitor es maltratado" : los adolescentes que pegan a sus padres

Vicente, Cindy 21 November 2013 (has links)
Les adolescents qui frappent leurs parents sont issus de familles dans lesquelles la violence est diffuse. Ceci nous a amenée à l’hypothèse que la problématique des limites était en cause à un niveau intrapsychique, intersubjectif et transpsychique. Pour répondre à cette hypothèse nous avons employé deux approches méthodologiques. La première est quantitative, basée sur l'étude de 52 situations d’adolescents frappeurs qui mettent en avant la perception des professionnels sur ces cas. La seconde méthode s’appuie sur des rencontres cliniques auprès de trois familles, suivies durant plusieurs mois. Les résultats ont mis en évidence que les jeunes frappeurs sont dans une problématique limite, centrale dans leur fonctionnement psychique. Ces limites sont également défaillantes entre les membres de la famille et entre les générations. Ceci est en lien avec un manque de contenance des barrières de pare-excitation. À l’adolescence le fantasme « un enfant est battu » réermerge, le jeune se situe dans une phase précédent celle-ci : « un parent est battu ». Dans une impossibilité à la critique et au meurtre symbolique, l’adolescent reste figé dans un fonctionnement où il met en acte ce fantasme. Le jeune et le parent se retrouvent dans une difficulté en miroir, figés dans cet impossible critique du lien. D’un point de vue familial, l’adolescent prend le rôle de porte-voix des différentes générations et crée par son acte une distance afin de pallier le manque de frontières générationnelles. / Adolescents who are hitting their parents are in families in which violence is abundant. This led us to the hypothesis that the problem of limits was involved, in the intrapsychic problems, intersubjective and transpsychic. To answer at this hypothesis different methods were used. The first is quantitative, it’s from 52 young hitters and highlights the perception of professionals in these situations. The second method is based on clinical encounters with three families, over a period of several months. The results highlights that young hitters are in a limited problems that is central to their psychic function. These limits are also failing between family members and generations. This is caused by a lack of attitude as a barriers and protective shield. At the adolescence age the fantasy "a child being beaten" reappears, the youth is in a phase preceding: "a parent is beaten." In the impossibility to criticism and symbolic murder, the teenager remains frozen in a operation system where he enacts this fantasy. The youth and the parents are in a mirror difficulty frozen in that impossible critical link. From a family point of view, the teen is the spokesman of the different generations and create a distance by his act to overcome the lack of generational boundaries. / Los adolescentes que pegan a sus padres se encuentran en familias donde la violencia es difusa. Esto nos lleva a la hipótesis de que la problemática de los límites está cuestionada, en la problemática intrafísica, intersubjetiva y transpsiquica. Para responder a esta hipótesis diferentes métodos han sido empleados. El primero es cuantitativo, y surge de 52 situaciones de adolescentes maltratadores y prioriza la percepción de los profesionales sobre estas situaciones. El segundo método se basa en los encuentros clínicos a partir de tres familias, seguidas durante varios meses. Los resultados han puesto en evidencia que los jóvenes maltratadores se sitúan en una problemática límite que es central en sus funcionamientos psíquicos. Estos límites también son ineficaces entre los miembros de la familia y entre las generaciones. Éstos están causados por una falta de continencia de las barreras de para- excitación. En la adolescencia la fantasía "un niño maltratado" resurge, el joven se sitúa en una fase precedente a ésta: "un progenitor es maltratado". Dentro de la imposibilidad a la crítica y a la muerte simbólica, el adolescente se mantiene fijado en un funcionamiento donde activa esta fantasía. El joven y el progenitor se reencuentran dentro de una dificultad en espejo fijada dentro de esta imposible crítica del vínculo. Desde un punto de vista familiar, el adolescente se sitúa como porta voz entre las diferentes generaciones y crea a través de su acción una distancia con el fin de suplir la falta de fronteras generacionales.
35

Regression Modeling of Time to Event Data Using the Ornstein-Uhlenbeck Process

Erich, Roger Alan 16 August 2012 (has links)
No description available.
36

Evaluation des risques sismiques par des modèles markoviens cachés et semi-markoviens cachés et de l'estimation de la statistique / Seismic hazard assessment through hidden Markov and semi-Markov modeling and statistical estimation

Votsi, Irène 17 January 2013 (has links)
Le premier chapitre présente les axes principaux de recherche ainsi que les problèmes traités dans cette thèse. Plus précisément, il expose une synthèse sur le sujet, en y donnant les propriétés essentielles pour la bonne compréhension de cette étude, accompagnée des références bibliographiques les plus importantes. Il présente également les motivations de ce travail en précisant les contributions originales dans ce domaine. Le deuxième chapitre est composé d’une recherche originale sur l’estimation du risque sismique, dans la zone du nord de la mer Egée (Grèce), en faisant usage de la théorie des processus semi-markoviens à temps continue. Il propose des estimateurs des mesures importantes qui caractérisent les processus semi-markoviens, et fournit une modélisation dela prévision de l’instant de réalisation d’un séisme fort ainsi que la probabilité et la grandeur qui lui sont associées. Les chapitres 3 et 4 comprennent une première tentative de modélisation du processus de génération des séismes au moyen de l’application d’un temps discret des modèles cachés markoviens et semi-markoviens, respectivement. Une méthode d’estimation non paramétrique est appliquée, qui permet de révéler des caractéristiques fondamentales du processus de génération des séismes, difficiles à détecter autrement. Des quantités importantes concernant les niveaux des tensions sont estimées au moyen des modèles proposés. Le chapitre 5 décrit les résultats originaux du présent travail à la théorie des processus stochastiques, c’est- à-dire l’étude et l’estimation du « Intensité du temps d’entrée en temps discret (DTIHT) » pour la première fois dans des chaînes semi-markoviennes et des chaînes de renouvellement markoviennes cachées. Une relation est proposée pour le calcul du DTIHT et un nouvel estimateur est présenté dans chacun de ces cas. De plus, les propriétés asymptotiques des estimateurs proposés sont obtenues, à savoir, la convergence et la normalité asymptotique. Le chapitre 6 procède ensuite à une étude de comparaison entre le modèle markovien caché et le modèle semi-markovien caché dans un milieu markovien et semi-markovien en vue de rechercher d’éventuelles différences dans leur comportement stochastique, déterminé à partir de la matrice de transition de la chaîne de Markov (modèle markovien caché) et de la matrice de transition de la chaîne de Markov immergée (modèle semi-markovien caché). Les résultats originaux concernent le cas général où les distributions sont considérées comme distributions des temps de séjour ainsi que le cas particulier des modèles qui sont applique´s dans les chapitres précédents où les temps de séjour sont estimés de manière non-paramétrique. L’importance de ces différences est spécifiée à l’aide du calcul de la valeur moyenne et de la variance du nombre de sauts de la chaîne de Markov (modèle markovien caché) ou de la chaîne de Markov immergée (modèle semi-markovien caché) pour arriver dans un état donné, pour la première fois. Enfin, le chapitre 7 donne des conclusions générales en soulignant les points les plus marquants et des perspectives pour développements futurs. / The first chapter describes the definition of the subject under study, the current state of science in this area and the objectives. In the second chapter, continuous-time semi-Markov models are studied and applied in order to contribute to seismic hazard assessment in Northern Aegean Sea (Greece). Expressions for different important indicators of the semi- Markov process are obtained, providing forecasting results about the time, the space and the magnitude of the ensuing strong earthquake. Chapters 3 and 4 describe a first attempt to model earthquake occurrence by means of discrete-time hidden Markov models (HMMs) and hidden semi-Markov models (HSMMs), respectively. A nonparametric estimation method is followed by means of which, insights into features of the earthquake process are provided which are hard to detect otherwise. Important indicators concerning the levels of the stress field are estimated by means of the suggested HMM and HSMM. Chapter 5 includes our main contribution to the theory of stochastic processes, the investigation and the estimation of the discrete-time intensity of the hitting time (DTIHT) for the first time referring to semi-Markov chains (SMCs) and hidden Markov renewal chains (HMRCs). A simple formula is presented for the evaluation of the DTIHT along with its statistical estimator for both SMCs and HMRCs. In addition, the asymptotic properties of the estimators are proved, including strong consistency and asymptotic normality. In chapter 6, a comparison between HMMs and HSMMs in a Markov and a semi-Markov framework is given in order to highlight possible differences in their stochastic behavior partially governed by their transition probability matrices. Basic results are presented in the general case where specific distributions are assumed for sojourn times as well as in the special case concerning the models applied in the previous chapters, where the sojourn time distributions are estimated non-parametrically. The impact of the differences is observed through the calculation of the mean value and the variance of the number of steps that the Markov chain (HMM case) and the EMC (HSMM case) need to make for visiting for the first time a particular state. Finally, Chapter 7 presents concluding remarks, perspectives and future work.
37

Cadeias de Markov Quânticas / Quantum Markov Chains

Santos, Raqueline Azevedo Medeiros 05 March 2010 (has links)
Made available in DSpace on 2015-03-04T18:51:17Z (GMT). No. of bitstreams: 1 dissertacao_raqueline.pdf: 1022175 bytes, checksum: 12f505a41f92171e321e1b57c568631a (MD5) Previous issue date: 2010-03-05 / Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior / In Computer Science, random walks are used in randomized algorithms, specially in search algorithms, where we desire to find a marked state in a Markov chain.In this type of algorithm,it is interesting to study the Hitting Time, which is associated to its computational complexity. In this context, we describe the classical theory of Markov chains and random walks,as well as their quantum analogue.In this way,we define the Hitting Time under the scope of quantum Markov chains. Moreover, analytical expressions calculated for the quantum Hitting Time and for the probability of finding a marked element on the complete graph are presented as the new results of this dissertation. / Em Ciência da Computação, os caminhos aleatórios são utilizados em algoritmos randômicos, especialmente em algoritmos de busca, quando desejamos encontrar um estado marcado numa cadeia de Markov. Nesse tipo de algoritmo é interessante estudar o Tempo de Alcance, que está associado a sua complexidade computacional. Nesse contexto, descrevemos a teoria clássica de cadeias de Markov e caminhos aleatórios, assim como o seu análogo quântico. Dessa forma, definimos o Tempo de Alcance sob o escopo das cadeias de Markov quânticas. Além disso, expressões analíticas calculadas para o tempo de Alcance quântico e para a probabilidade de encontrarmos um elemento marcado num grafo completo são apresentadas como os novos resultados dessa dissertação.
38

Monte Carlo Simulation of Boundary Crossing Probabilities with Applications to Finance and Statistics

Gür, Sercan 04 1900 (has links) (PDF)
This dissertation is cumulative and encompasses three self-contained research articles. These essays share one common theme: the probability that a given stochastic process crosses a certain boundary function, namely the boundary crossing probability, and the related financial and statistical applications. In the first paper, we propose a new Monte Carlo method to price a type of barrier option called the Parisian option by simulating the first and last hitting time of the barrier. This research work aims at filling the gap in the literature on pricing of Parisian options with general curved boundaries while providing accurate results compared to the other Monte Carlo techniques available in the literature. Some numerical examples are presented for illustration. The second paper proposes a Monte Carlo method for analyzing the sensitivity of boundary crossing probabilities of the Brownian motion to small changes of the boundary. Only for few boundaries the sensitivities can be computed in closed form. We propose an efficient Monte Carlo procedure for general boundaries and provide upper bounds for the bias and the simulation error. The third paper focuses on the inverse first-passage-times. The inverse first-passage-time problem deals with finding the boundary given the distribution of hitting times. Instead of a known distribution, we are given a sample of first hitting times and we propose and analyze estimators of the boundary. Firstly, we consider the empirical estimator and prove that it is strongly consistent and derive (an upper bound of) its asymptotic convergence rate. Secondly, we provide a Bayes estimator based on an approximate likelihood function. Monte Carlo experiments suggest that the empirical estimator is simple, computationally manageable and outperforms the alternative procedure considered in this paper.
39

Delaunay Graphs for Various Geometric Objects

Agrawal, Akanksha January 2014 (has links) (PDF)
Given a set of n points P ⊂ R2, the Delaunay graph of P for a family of geometric objects C is a graph defined as follows: the vertex set is P and two points p, p' ∈ P are connected by an edge if and only if there exists some C ∈ C containing p, p' but no other point of P. Delaunay graph of circle is often called as Delaunay triangulation as each of its inner face is a triangle if no three points are co-linear and no four points are co-circular. The dual of the Delaunay triangulation is the Voronoi diagram, which is a well studied structure. The study of graph theoretic properties on Delaunay graphs was motivated by its application to wireless sensor networks, meshing, computer vision, computer graphics, computational geometry, height interpolation, etc. The problem of finding an optimal vertex cover on a graph is a classical NP-hard problem. In this thesis we focus on the vertex cover problem on Delaunay graphs for geometric objects like axis-parallel slabs and circles(Delaunay triangulation). 1. We consider the vertex cover problem on Delaunay graph of axis-parallel slabs. It turns out that the Delaunay graph of axis-parallel slabs has a very special property — its edge set is the union of two Hamiltonian paths. Thus, our problem reduces to solving vertex cover on the class of graphs whose edge set is simply the union of two Hamiltonian Paths. We refer to such a graph as a braid graph. Despite the appealing structure, we show that deciding k-vertex cover on braid graphs is NP-complete. This involves a rather intricate reduction from the problem of finding a vertex cover on 2-connected cubic planar graphs. 2. Having established the NP-hardness of the vertex cover problem on braid graphs, we pursue the question of improved fixed parameter algorithms on braid graphs. The best-known algorithm for vertex cover on general graphs has a running time of O(1.2738k + kn) [CKX10]. We propose a branching based fixed parameter tractable algorithm with running time O⋆(1.2637k) for graphs with maximum degree bounded by four. This improves the best known algorithm for this class, which surprisingly has been no better than the algorithm for general graphs. Note that this implies faster algorithms for the class of braid graphs (since they have maximum degree at most four). 3. A triangulation is a 2-connected plane graph in which all the faces except possibly the outer face are triangles, we often refer to such graphs as triangulated graphs. A chordless-NST is a triangulation that does not have chords or separating triangles (non-facial triangles). We focus on the computational problem of optimal vertex covers on triangulations, specifically chordless-NST. We call a triangulation Delaunay realizable if it is combinatorially equivalent to some Delaunay triangulation. Characterizations of Delaunay triangulations have been well studied in graph theory. Dillencourt and Smith [DS96] showed that chordless-NSTs are Delaunay realizable. We show that for chordless-NST, deciding the vertex cover problem is NP-complete. We prove this by giving a reduction from vertex cover on 3-connected, triangle free planar graph to an instance of vertex cover on a chordless-NST. 4. If the outer face of a triangulation is also a triangle, then it is called a maximal planar graph. We prove that the vertex cover problem is NP-complete on maximal planar graphs by reducing an instance of vertex cover on a triangulated graph to an instance of vertex cover on a maximal planar graph.
40

Perturbed discrete time stochastic models

Petersson, Mikael January 2016 (has links)
In this thesis, nonlinearly perturbed stochastic models in discrete time are considered. We give algorithms for construction of asymptotic expansions with respect to the perturbation parameter for various quantities of interest. In particular, asymptotic expansions are given for solutions of renewal equations, quasi-stationary distributions for semi-Markov processes, and ruin probabilities for risk processes. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Manuscript. Paper 5: Manuscript. Paper 6: Manuscript.</p>

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