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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.
421

[en] EGO-HISTORIES: THEORETICAL ALTERNATIVES REPERTOIRES / [pt] EGO-HISTÓRIAS: REPERTÓRIOS TEÓRICOS ALTERNATIVOS

FLAVIA PINTO LEIROZ 28 March 2019 (has links)
[pt] A tese Ego-histórias: repertórios teóricos alternativos, dedicada à investigação de novos discursos autobiográficos situados nos limiares entre historiografia, biografia e ficção, tem por objetivo a construção de ferramentas teóricas a partir da análise crítica de quadros conceituais vigentes. Na ótica de novas questões, são tematizadas e reavaliadas, de um lado, posições tradicionais ancoradas na unidade do sujeito, na autenticidade de sua fala e na ilusão referencial, legitimadas pela oposição dicotômica de pares conceituais, como real/ficcional, autenticidade/encenação, sujeito/objeto. Por outro lado, são oferecidos modelos analíticos e estratégias descritivas que permitem entender a escrita autobiográfica atual como gênero híbrido, de configuração plural, que desafia pactos autobiográficos fundados sobre a identidade entre as instâncias autoral, narrativa e ficcional. Os próprios processos autorreflexivos subjacentes à escrita de si são problematizados à luz de novas convicções epistemológicas construtivistas (S. SCHMIDT; H. MATURANA) e de molduras sistêmicas entendidas como catalisadores de complexidade. No horizonte dessas concepções, são discutidas, entre outras, formas de autoanálise (P. BOURDIEU) e projetos autobiográficos (E. SAID) convergindo ambos na produção de ego-histórias responsáveis pela transformação de teorias em narrativa e permitindo aos teóricos a fusão entre observador e objeto observado, baseada no conceito de observação de segunda ordem. Desse modo, são ensaiados novos vínculos entre suas ideias particulares e a inserção delas no contexto contemporâneo que escapam a relações tradicionais de causalidade e acentuam a responsabilidade dos próprios produtores. Em perspectiva paralela, é analisada a relação entre corpo e escrita e entre emoção e experiência, vigorosamente presentes e ressonantes como propostas conceituais que não perdem sua força interpelativa pela transformação em meras abstrações filosóficas, mas exibem seu poder pela opção construtora de uma vida no mundo. Em seu conjunto, a tese representa uma contribuição inovadora para a construção de repertórios teóricos alternativos que permitem elaborar um saber adequado às novas configurações de escritos autobiográficos. / [en] The thesis Ego-histories: theoretical alternatives repertoires, dedicated to research into new autobiographical discourses situated in the thresholds between historiography, biography and fiction, aims to build theoretical tools from the review of existing conceptual frameworks. In the analysis of new issues, are highlighted and reevaluated, on the one hand, traditional positions anchored in the unity of the subject, the authenticity of its discourse and referential illusion, legitimized by the dichotomous opposition of conceptual pairs such as real/fictional, authenticity/staging, subject/object. On the other hand, are offered analytical models and descriptive strategies that allow to understand the current autobiographical writing as a hybrid genre, with plural configurations that challenge the autobiographical pact based on the identity between instances of authorship, narrative and the fictional. The very processes underlying the self-reflexive writing itself, are analyzed in the light of new constructivist epistemological convictions (S. SCHMIDT; H. MATURANA) and systemic frames understood as a catalyst of complexity. In the perspective of these concepts are discussed, among others, forms of self-analysis (P. BOURDIEU) and autobiographical projects (E. SAID) converging both in the production of ego-histories responsible for transforming theories in narratives and thus allowing the theoretical melting between observer and observed object, based on the concept of second-order observation. Thus, are tested new links between their particular ideas and insertion them in the contemporary context that escape of traditional relations of causality and emphasize the responsibility of their producers. In a parallel perspective, is analyzed the relation between body and writing and between emotion and experience, vigorously present and resonant as conceptual proposals that do not lose its strength of interpellation by transforming them into mere philosophical abstractions, but they exhibit their power by the option of building a life in the world. Overall, the thesis represents an innovative contribution to the construction of alternative theoretical repertoires that allow to draw up a knowledge appropriate to produce a new settings of autobiographical writings.
422

Multi-objective Control on Inverter-Based Microgrids

Gonzales Zurita, Óscar Omar 10 March 2024 (has links)
[ES] El aumento en el uso de combustibles fósiles para la generación de energía ha contribuido significativamente a la crisis del calentamiento global. Diferentes lugares alejados de la infraestructura eléctrica emplean generadores a base de gasolina que aumentan la contaminación ambiental. En este contexto, la introducción masiva de microrredes en la sociedad ha traído oportunidades para la generación de energía de forma distribuida, beneficiando a personas en todo el mundo. Por ejemplo, las microrredes pueden brindar electricidad a poblaciones vulnerables que viven en áreas remotas con acceso limitado a infraestructuras de transmisión y distribución. Además, las microrredes promueven el uso de recursos renovables, reduciendo el impacto ambiental en comparación con los métodos tradicionales de generación de electricidad, como las plantas de energía térmica o las instalaciones nucleares. Además, las microrredes permiten la generación de electricidad a pequeña escala, lo que permite que las familias logren la independencia energética y vendan el exceso de energía a la compañía eléctrica local. Cualquier inversor en una microrred necesita un algoritmo de control para realizar una regulación en bucle cerrado. En este contexto, el control por modos deslizantes de segundo orden es una estrategia de control robusta que ha ganado atención en las aplicaciones de inversores de microrredes. Mediante el uso de este enfoque, el inversor puede lograr un control preciso y rápido, incluso en presencia de incertidumbres y perturbaciones. El uso de estrategias de control robustas mejora la estabilidad y el rendimiento general del sistema de microrredes, asegurando una gestión de energía óptima. El proceso de ajuste es esencial para los algoritmos de control en bucle cerrado, ya que modifica la respuesta del controlador para alcanzar los objetivos de control. La optimización por enjambre de partículas (PSO por sus siglas en inglés) es un eficiente algoritmo de optimización empleado en controladores en lazo cerrado que puede resolver de manera efectiva problemas multi-objetivo formulados en una sola función de costo. Los parámetros de control del inversor de la microrred pueden ser optimizados mediante la utilización de PSO para lograr los objetivos deseados, ajustando de manera eficiente una estrategia de control. Para controladores por modos deslizantes, algunas estrategias de ajuste se basan en técnicas heurísticas. La función de costo única resuelve varios problemas en una microrred, pero existen dificultades cuando diferentes objetivos en un proceso no pueden ser mejorados simultáneamente debido a su relación conflictiva. Estrategias como Algoritmos Genéticos Multi-Objetivo (MOGA por sus siglas en inglés), Evolución Diferencial Multi-Objetivo (MODE por sus siglas en inglés) y Algoritmo Artificial de Ovejas Multi-Objetivo (MOASA por sus siglas en inglés), han demostrado su capacidad para mejorar el rendimiento del inversor mediante la optimización de objetivos conflictivos. Estos algoritmos pueden equilibrar de manera efectiva objetivos como la reducción del tiempo de respuesta y la minimización del sobreimpulso en la señal de salida del inversor. En consecuencia, el rendimiento general y la eficiencia de los inversores de la microrred pueden mejorar. La integración de algoritmos de control multi-objetivo en los inversores de la microrred tiene un gran potencial para abordar los desafíos de gestión de energía y optimizar el rendimiento. Los inversores de la microrred pueden lograr una mayor estabilidad, eficiencia y confiabilidad utilizando técnicas como el control por modos deslizantes de segundo orden y algoritmos de optimización como PSO, MOGA, MODE y MOASA. Al adoptar estos enfoques, se presenta una nueva metodología para un futuro energético más sostenible y resiliente, al tiempo que se mitigan los efectos adversos del calentamiento global causado por el consumo de combustibles fósiles en la generación convencional de energía. / [CA] L'augment en l'ús de combustibles fòssils per a la generació d'energia ha contribuït significativament a la crisi de l'escalfament global. Diferents llocs allunyats de la infraestructura elèctrica empleen generadors a base de gasolina que augmenten la contaminació ambiental. En aquest context, la introducció massiva de microxarxes a la societat ha comportat oportunitats per a la generació d'energia de forma distribuïda, beneficiant persones arreu del món. Per exemple, les microxarxes poden proporcionar electricitat a poblacions vulnerables que viuen en àrees remotes amb accés limitat a infraestructures de transmissió i distribució. A més, les microxarxes promouen l'ús de recursos renovables, reduint l'impacte ambiental en comparació amb els mètodes tradicionals de generació d'electricitat, com les plantes d'energia tèrmica o les instal·lacions nuclears. A més a més, les microxarxes permeten la generació d'electricitat a petita escala, la qual cosa permet que les famílies aconsegueixin la independència energètica i venguen l'excedent d'energia a la companyia elèctrica local. Qualsevol inversor en una microxarxa necessita un algoritme de control per a realitzar una regulació en bucle tancat. En aquest context, el control per modes lliscants de segon ordre és una estratègia de control robusta que ha guanyat atenció en les aplicacions d'inversors de microxarxes. Mitjançant l'ús d'aquest enfocament, l'inversor pot aconseguir un control precís i ràpid, fins i tot en presència d'incerteses i pertorbacions. L'ús d'estratègies de control robustes millora l'estabilitat i el rendiment general del sistema de microxarxes, assegurant una gestió d'energia òptima. El procés d'ajust és essencial pels algoritmes de control en bucle tancat, ja que modifica la resposta del controlador per a aconseguir els objectius de control. L'optimització per enjambre de partícules (PSO per les seues sigles en anglés) és un eficient algoritme d'optimització emprat en controladors en bucle tancat que pot resoldre de manera efectiva problemes multi-objectiu formulats en una sola funció de cost. Els paràmetres de control de l'inversor de la microxarxa poden ser optimitzats mitjançant l'utilització de PSO per a aconseguir els objectius desitjats, ajustant de manera eficient una estratègia de control. Per a controladors per modes lliscants, algunes estratègies d'ajust es basen en tècniques heurístiques. La funció de cost única resol diversos problemes en una microxarxa, però existeixen dificultats quan diferents objectius en un procés no poden ser millorats simultàniament a causa de la seua relació conflictiva. Estratègies com Algorismes Genètics Multi-Objectiu (MOGA per les seues sigles en anglés), Evolució Diferencial Multi-Objectiu (MODE per les seues sigles en anglés) i Algorisme Artificial de Xais Multi-Objectiu (MOASA per les seues sigles en anglés), han demostrat la seua capacitat per a millorar el rendiment de l'inversor mitjançant l'optimització d'objectius conflictius. Aquests algorismes poden equilibrar de manera efectiva objectius com la reducció del temps de resposta i la minimització del sobreguiny a la senyal de sortida de l'inversor. En conseqüència, el rendiment general i l'eficiència dels inversors de la microxarxa poden millorar. La integració d'algorismes de control multi-objectiu en els inversors de la microxarxa té un gran potencial per a abordar els desafiaments de gestió d'energia i optimitzar el rendiment. Els inversors de la microxarxa poden aconseguir una major estabilitat, eficiència i fiabilitat utilitzant tècniques com el control per modes lliscants de segon ordre i algorismes d'optimització com PSO, MOGA, MODE i MOASA. En adoptar aquests enfocaments, es presenta una nova metodologia per a un futur energètic més sostenible i resilient, al mateix temps que es mitiguen els efectes adversos de l'escalfament global causat pel consum de combustibles fòssils en la generació convencional d'energia. / [EN] The increase in fossil fuel usage for power generation has significantly contributed to the global warming crisis. Various remote areas, detached from electrical infrastructure, rely on gasoline-based generators that escalate environmental pollution. In this context, the widespread implementation of microgrids in society has brought forth opportunities for distributed energy generation, benefiting people worldwide. For instance, microgrids can provide electricity to vulnerable populations in remote areas with limited access to transmission and distribution infrastructures. Furthermore, these microgrids advocate for using renewable resources, diminishing environmental impact compared to traditional methods such as thermal power plants or nuclear facilities. Additionally, microgrids enable small-scale electricity generation, empowering families to achieve energy independence and sell surplus energy to local power companies. Any investor in a microgrid requires a closed-loop control algorithm. In this realm, the second-order sliding mode control is a robust strategy garnering attention in microgrid inverter applications. Through this approach, the inverter can achieve precise and rapid control despite uncertainties and disturbances. Using robust control strategies enhances microgrid systems' stability and overall performance, ensuring optimal energy management. Adjustment processes are pivotal for closed-loop control algorithms, modifying the controller's response to meet control objectives. Particle Swarm Optimization (PSO) is an efficient optimization algorithm employed in closed-loop controllers that can effectively solve multi-objective problems formulated in a single cost function. Control parameters of the microgrid inverter can be optimized using PSO to attain desired objectives, efficiently fine-tuning a control strategy. For sliding mode controllers, some adjustment strategies rely on heuristic techniques. While a single cost function resolves various issues within a microgrid, difficulties arise when different objectives in a process cannot be simultaneously improved due to conflicting relationships. Strategies like Multi-Objective Genetic Algorithms (MOGA), Multi-Objective Differential Evolution (MODE), and Multi-Objective Artificial Sheep Algorithm (MOASA) have proven their ability to enhance inverter performance by optimizing conflicting objectives. These algorithms effectively balance objectives like reducing response time and minimizing overshoot in the inverter's output signal. Consequently, the overall performance and efficiency of microgrid inverters can be enhanced. Integrating multi-objective control algorithms into microgrid inverters holds significant potential in addressing energy management challenges and optimizing performance. Microgrid inverters can achieve greater stability, efficiency, and reliability by utilizing second-order sliding mode control and optimization algorithms like PSO, MOGA, MODE, and MOASA. By embracing these approaches, a new methodology emerges for a more sustainable and resilient energy future while mitigating the adverse effects of global warming caused by conventional fossil fuel consumption in power generation. / Gonzales Zurita, ÓO. (2024). Multi-objective Control on Inverter-Based Microgrids [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/203120
423

Differential effects of script system acquisition and social immersion experience on face perception / Evidence from event-related brain potentials

Ma, Xiaoli 19 January 2023 (has links)
Informelle Berichte zeigten größere Amplituden der durch Gesichter ausgelösten N170 Komponente im Ereigniskorrelierten Potenzial (EKP) bei asiatischen als bei kaukasischen Probanden. Als mögliche Ursache vermutete ich unterschiedliche Erfahrungen mit logographischen bzw. alphabetischen Schriftsystemen (Schriftsystem-Hypothese) oder die verstärkte Exposition mit unbekannten Gesichtern während der Immersion in eine neue soziale oder ethnische Umgebung (soziale Immersions-Hypothese). Zur Überprüfung dieser Hypothesen führte ich zwei kulturvergleichende Studien mit Erwachsenen bzw. Kindern durch. In Studie 1 untersuchte ich einheimische Chinesen und nicht-chinesische Auswärtige in Hongkong und deutsche Einheimische und chinesische Auswärtige in Berlin. Die Auswärtigen an beiden Orten zeigten größere N170 Amplituden auf Gesichter als die Einheimischen. Außerdem zeigten Deutsche, die erst kurze Zeit in Berlin lebten ähnliche Amplituden wie langjährige Einheimische. Insgesamt unterstützt Studie 1 die soziale Immersions-Hypothese, dass die Immersion in eine neue ethnische Umgebung zu einer Vergrößerung der N170 führt. Studie 2 untersuchte die Schriftsystem-Hypothese bei chinesischen und deutschen Erstlesern am Ende der ersten oder zu Beginn des zweiten Schuljahres an ihrem jeweiligen Heimatort. Die Ergebnisse unterstützen die Schriftsystem-Hypothese, dass chinesische Kinder eine größere N170 auf Gesichter zeigen als deutsche. Insgesamt konnte die vorliegende Dissertation zwei neue Einfluss-Faktoren auf das Gesichterverarbeitungs-System nachweisen, das erworbene Schriftsystem (logographische versus alphabetisch) und die Erfahrung sozialer Immersion in eine neue ethnische Umgebung. Diese Effekte zu ganz unterschiedlichen Zeitpunkten der Entwicklung (Kindheit vs. junges Erwachsenen-Alter) zeigen, dass das Gesichterverarbeitungs-System über lange Zeit seine Plastizität behält. / Informal reports have shown larger face-elicited N170 component of event-related potential (ERP) in Asians than Caucasians participants. I proposed that different experience with logographic versus alphabetic scripts (script system hypothesis) or by exposure to abundant novel faces during the immersion into a new social and/or ethnic environment (social immersion hypothesis) as a possible cause. To test these hypotheses, I conducted two cross-cultural ERP studies with adults and Children. In Study 1, I examined Chinese locals and non-Chinese foreigners in Hongkong, and German locals and Chinese foreigners in Berlin. It turned out that the foreigners in both locations showed larger N170 amplitudes to faces than the locals. In addition, Germans who had only lived in Berlin for a short time showed similar face N170 amplitudes as long-term Berlin residents. In sum, Study 1 supports the social immersion hypothesis that immersing into a new ethnic environment drives an increase of face N170. Study 2 investigated the scripts system hypothesis in Chinese and German early readers assessed at the end of the first-grade or at the beginning of the second grade in their respective home towns. The findings support the script system hypothesis that Chinese children showed larger face N170 amplitudes than German children. Overall, the present thesis demonstrated two new influencing factors on the face processing system, the acquired script system (logographic vs. alphabetic) and the social immersion experience in a new ethnic environment. More specifically, learning to read a visually complex logographic Chinese script or immersing into an other-ethnic social environment facilitates early perceptual processing of faces. These effects acquired at different stages of development (early childhood versus young adulthood) show that the face processing system retains its plasticity over a long period of time.
424

The development of a therapist through participation in a reflecting team

Hanford, Ann Dowie 30 November 2004 (has links)
This thesis is a study of the development of a group of students during the time they spentworking as a reflecting team in family therapy. Due to an increase in the number of students enrolled for the Masters degree in Educational Psychology in the years from 2001, there was concern about the students experience of family therapy, since they would not all be likely to counsel a family. The study, which was undertaken over a period of two years, allows a comparison of two different experiences of being part of a reflecting team. The first year the whole group formed a single team, whereas, the group in the second year split into two teams, working on a fortnightly basis. The growth of the students as therapists was assessed by means of questionnaires and an interview with the trainer in terms of self-reflection, willingness to risk. / Social work / MA(SS)(Mental Health)
425

Law in 3-Dimensions

2013 March 1900 (has links)
This project, overall, involves a theory of law as dimensions. Throughout the history of the study of law, many different theoretical paradigms have emerged proffering different and competing ways to answer the question ‘what is law’? Traditionally, many of these paradigms have been at irreconcilable odds with one another. Notwithstanding this seeming reality, the goal of this project was to attempt to take three of the leading paradigms in legal theory and provide a way to explain how each might fit into a single coherent theory of law. I set out to accomplish this by drawing on the field of theoretical physics and that field’s use of spatial dimensions in explaining various physical phenomena. By engaging in a dimensional analysis of law, I found that I was able to place each paradigm within its own dimension with that dimension being defined by a specific element of time, and in doing so much of the conflict between the paradigms came to be ameliorated. The project has been divided into two main parts. PART I discusses the fundamentals of legal theory (Chapter 1) and the fundamentals of dimensions (Chapter 2). These fundamentals provide a foundation for a dimensional analysis of law which takes place throughout PART II. In Chapter 3, I argue that the three fundamental theses of Positivism coalesce with the 1st-dimension of law, which is defined as law as it exists at any one point in time. From there, I argue in Chapter 4 that the 2nd-dimension of law, being law as it exists between two points in time (i.e. when cases are adjudicated), is characterized by Pragmatism. I then turn, in Chapter 5, to argue that the 3rd-dimension of law, being law as it exists from the very first point in legal time to the ever changing present day, coalesces with the fundamental theses of Naturalism. Ultimately then, I argue that a theory of law as dimensions, through the vantage points of the specific elements of time, provides a more complete account of the nature of law.
426

Making sense of sudden personal transformation: a qualitative study on people’s beliefs about the facilitative factors and mechanisms of their abrupt and profound inner change.

Ilivitsky, Susan 21 June 2011 (has links)
Sudden personal transformation (SPT) was defined as a subjectively reported, positive, profound, and lasting personal change that follows a relatively brief and memorable inner experience. Although such change has been described in numerous biographies, works of fiction, and religious and scholarly texts, a consistent definition and systematic program of research is lacking in the psychological literature. Moreover, almost nothing is known about what causes such change from the subjective point of view of individuals who have experienced it first hand. This study used semi-structured interviews and thematic analysis to explore the common beliefs of three participants about the factors that facilitated and the mechanisms that caused their SPT. Findings reveal that all participants reported a life transition, feeling miserable, feeling exhausted, feeling unable to resolve adverse circumstances, reaching a breaking point, and support from others facilitated their individual SPT’s. All participants also indicated that a formalized activity or ceremony as well as a process outside of their conscious control (either a higher power or a deep inner wisdom) produced or caused their SPT’s. Implications for future research and counselling practice are discussed. / Graduate
427

The development of a therapist through participation in a reflecting team

Hanford, Ann Dowie 30 November 2004 (has links)
This thesis is a study of the development of a group of students during the time they spentworking as a reflecting team in family therapy. Due to an increase in the number of students enrolled for the Masters degree in Educational Psychology in the years from 2001, there was concern about the students experience of family therapy, since they would not all be likely to counsel a family. The study, which was undertaken over a period of two years, allows a comparison of two different experiences of being part of a reflecting team. The first year the whole group formed a single team, whereas, the group in the second year split into two teams, working on a fortnightly basis. The growth of the students as therapists was assessed by means of questionnaires and an interview with the trainer in terms of self-reflection, willingness to risk. / Social work / MA(SS)(Mental Health)
428

Quelques résultats sur les équations rétrogrades et équations aux dérivées partielles stochastiques avec singularités. / Some results on backward equations and stochastic partial differential equations with singularities

Piozin, Lambert 23 June 2015 (has links)
Cette thèse est consacrée à l'étude de quelques problèmes dans le domaine des équations différentielles stochastiques rétrogrades (EDSR), et leurs applications aux équations aux dérivées partielles.Dans le premier chapitre, nous introduisons la notion d'équation différentielle doublement stochastique rétrograde (EDDSR) avec condition terminale singulière. Nous étudions d’abord les EDDSR avec générateur monotone, et obtenons ensuite un résultat d'existence par un schéma d'approximation. Une dernière section établit le lien avec les équations aux dérivées partielles stochastiques, via l'approche solution faible développée par Bally, Matoussi en 2001.Le deuxième chapitre est consacré aux EDSR avec condition terminale singulière et sauts. Comme dans le chapitre précédent la partie délicate sera de prouver la continuité en T. Nous formulons des conditions suffisantes sur les sauts afin d'obtenir cette dernière. Une section établit ensuite le lien entre solution minimale de l'EDSR et équations intégro-différentielles. Enfin le dernier chapitre est dédié aux équations différentielles stochastiques rétrogrades du second ordre (2EDSR) doublement réfléchies. Nous avons établi l'existence et l'unicité de telles équations. Ainsi, il nous a fallu dans un premier temps nous concentrer sur le problème de réflexion par barrière supérieure des 2EDSR. Nous avons ensuite combiné ces résultats à ceux existants afin de donner un cadre correct aux 2EDSRDR. L'unicité est conséquence d'une propriété de représentation et l'existence est obtenue en utilisant les espaces shiftés, et les distributions de probabilité conditionnelles régulières. Enfin une application aux jeux de Dynkin et aux options Israëliennes est traitée dans la dernière section. / This thesis is devoted to the study of some problems in the field of backward stochastic differential equations (BSDE), and their applications to partial differential equations.In the first chapter, we introduce the notion of backward doubly stochastic differential equations (BDSDE) with singular terminal condition. A first work consists to study the case of BDSDE with monotone generator. We then obtain existing result by an approximating scheme built considering a truncation of the terminal condition. The last part of this chapter aim to establish the link with stochastic partial differential equations, using a weak solution approach developed by Bally, Matoussi in 2001.The second chapter is devoted to the BSDEs with singular terminal conditions and jumps. As in the previous chapter the tricky part will be to prove continuity in T. We formulate sufficient conditions on the jumps in order to obtain it. A section is then dedicated to establish a link between a minimal solution of our BSDE and partial integro-differential equations.The last chapter is dedicated to doubly reflected second order backward stochastic differential equations (2DRBSDE). We have been looking to establish existence and uniqueness for such equations. In order to obtain this, we had to focus first on the upper reflection problem for 2BSDEs. We combined then these results to those already existing to give a well-posedness context to 2DRBSDE. Uniqueness is established as a straight consequence of a representation property. Existence is obtained using shifted spaces, and regular conditional probability distributions. A last part is then consecrated to the link with some Dynkin games and Israeli options.
429

Řešení stability prutových konstrukcí / Stability solution of framed structures

Baxant, Radek January 2015 (has links)
This diploma thesis deals with the subject of slenderness bars’ stability assessment, especially in the steel structures. Before the assessment of bars in the frame constructions, we search for the influence of the computational model’s settings on the final result. The initial geometrical imperfections are examined on the model of Euler’s bar. The influence of the rigidity of girders on the poles’ buckling length is examined on the basic frame construction. The buckling lengths are assessed in the comparison with the figures we got from the statistical tables and the computational software. The influence of construction’s initial tilt and its replacement by the system of outer forces is examined on the frame structure. Three-hinged frame structure with variable cross-section member is designed then and the influence of non-linear calculations on the inner forces is studied. In the complex frame assessment, the influence of the number of parts of variable cross-section member on the bars’ buckling length is examined.
430

Mathematical modelling of image processing problems : theoretical studies and applications to joint registration and segmentation / Modélisation mathématique de problèmes relatifs au traitement d'images : étude théorique et applications aux méthodes conjointes de recalage et de segmentation

Debroux, Noémie 15 March 2018 (has links)
Dans cette thèse, nous nous proposons d'étudier et de traiter conjointement plusieurs problèmes phares en traitement d'images incluant le recalage d'images qui vise à apparier deux images via une transformation, la segmentation d'images dont le but est de délimiter les contours des objets présents au sein d'une image, et la décomposition d'images intimement liée au débruitage, partitionnant une image en une version plus régulière de celle-ci et sa partie complémentaire oscillante appelée texture, par des approches variationnelles locales et non locales. Les relations étroites existant entre ces différents problèmes motivent l'introduction de modèles conjoints dans lesquels chaque tâche aide les autres, surmontant ainsi certaines difficultés inhérentes au problème isolé. Le premier modèle proposé aborde la problématique de recalage d'images guidé par des résultats intermédiaires de segmentation préservant la topologie, dans un cadre variationnel. Un second modèle de segmentation et de recalage conjoint est introduit, étudié théoriquement et numériquement puis mis à l'épreuve à travers plusieurs simulations numériques. Le dernier modèle présenté tente de répondre à un besoin précis du CEREMA (Centre d'Études et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement) à savoir la détection automatique de fissures sur des images d'enrobés bitumineux. De part la complexité des images à traiter, une méthode conjointe de décomposition et de segmentation de structures fines est mise en place, puis justifiée théoriquement et numériquement, et enfin validée sur les images fournies. / In this thesis, we study and jointly address several important image processing problems including registration that aims at aligning images through a deformation, image segmentation whose goal consists in finding the edges delineating the objects inside an image, and image decomposition closely related to image denoising, and attempting to partition an image into a smoother version of it named cartoon and its complementary oscillatory part called texture, with both local and nonlocal variational approaches. The first proposed model addresses the topology-preserving segmentation-guided registration problem in a variational framework. A second joint segmentation and registration model is introduced, theoretically and numerically studied, then tested on various numerical simulations. The last model presented in this work tries to answer a more specific need expressed by the CEREMA (Centre of analysis and expertise on risks, environment, mobility and planning), namely automatic crack recovery detection on bituminous surface images. Due to the image complexity, a joint fine structure decomposition and segmentation model is proposed to deal with this problem. It is then theoretically and numerically justified and validated on the provided images.

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