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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.
521

Cremona Symmetry in Gromov-Witten Theory / Cremona Symmetry in Gromov-Witten Theory

Gholampour, Amin, Karp, Dagan, Payne, Sam 25 September 2017 (has links)
We establish the existence of a symmetry within the Gromov-Witten theory of CPn and its blowup along points. The nature of this symmetry is encoded in the Cremona transform and its resolution, which lives on the toric variety of the permutohedron. This symmetry expresses some difficult to compute invariants in terms of others less difficult to compute. We focus on enumerative implications; in particular this technique yields a one line proof of the uniqueness of the rational normal curve. Our method involves a study of the toric geometry of the permutohedron, and degeneration of Gromov-Witten invariants. / En este trabajo establecemos la existencia de una simetra en el marco de la teora de Gromov-Witten para CPn y su explosion a lo largo de puntos. La naturaleza de esta simetra queda codicada en la transformacion de Cremona y su resolucion en una variedad torica del permutoedro. Esta simetra expresa algunos invariantes difciles de calcular junto con otros que no lo son tanto. Nos centramos en implicaciones enumerativas; en particular esta tecnica ofrece una prueba enuna lnea de la unicidad de la curva racional normal. Nuestro metodo involucra un estudio de la geometra torica del permutoedro, as como el de la degeneracion de los invariantes de Gromov-Witten.
522

Narcolepsia: muito além do sono; eficácia adaptativa do ego, equilíbrio psíquico e destinações inconscientes / Narcolepsy: way beyond sleep; ego\'s adaptive efficiency, psychological equilibrium and unconscious destinations

Carmen Sylvia de Alcantara Oliveira Proença 08 August 2003 (has links)
Narcolepsia é uma doença neurológica crônica caracterizada por sonolência diurna excessiva e ataques de sono. Ocorre na população de uma para cada mil pessoas. Fenômenos de sono REM (rapid eye movement), cataplexia, paralisia do sono e alucinações hipnagógicas podem também ocorrer. Afeta todos os aspectos da vida e pode causar dificuldades para os pacientes em manter seus empregos, nos relacionamentos interpessoais e riscos de acidentes devido à sonolência excessiva e à cataplexia. Acredita-se que seja causada por um interjogo de fatores genéticos e ambientais. O risco para familiares de primeiro grau é estimado em de 1-2%. Recentemente foi demonstrado que os pacientes com narcolepsia têm uma deficiência de hipocretina também chamada de orexina na parte lateral do hipotálamo. O presente trabalho teve como objetivos: a) caracterizar os aspectos psicodinâmicos mais freqüentes da amostra; b) verificar a eficácia adaptativa do ego; c) verificar o equilíbrio e o funcionamento psíquico e relacionar com aspectos clínicos dos pacientes. A amostra foi de 23 pacientes portadores de narcolepsia, 15 mulheres e 8 homens, com média de idade de 44 anos. Eles foram avaliados através da Escala Diagnóstica Adaptativa Operacionalizada (EDAO), de R. Simon. O Questionário do Sono, de Giglio, foi utilizado para levantar os principais problemas no sono e as conseqüências na qualidade de vida dos pacientes. A Escala de Sonolência Epworth avaliou a intensidade da sonolência diurna. A dinâmica do funcionamento mental foi avaliada através do Teste das Relações Objetais de Phillipson (TRO), segundo os pressupostos teóricos da psicanálise. Os resultados mostraram que: 1) a narcolepsia está associada a sério prejuízo na eficácia adaptativa, com diagnóstico de Adaptação Ineficaz Moderada e Severa na maioria dos sujeitos; 2) sonolência severa excessiva diurna, ataques de sono e sono noturno fracionado; 3) a análise do funcionamento psíquico revelou que estes pacientes apresentam respostas, as quais, na maioria das vezes, impedem seu desenvolvimento. Os principais mecanismos de defesa, mais freqüentes, são pertinentes à posição esquisoparanóide, medo de rejeição e abandono e desejo de proteção e contato. Revelou também dificuldades em relação aos vínculos interpessoais, com mecanismos de fuga e evitação principalmente nas situações grupais e de três pessoas. / Narcolepsy is a chronic brain disorder characterized by excessive daytime sleepiness and sleep attacks. It affects up to one in a thousand people. Rapid eye movement (REM) sleep phenomena such as cataplexy, sleep paralysis and hypnagogic hallucinations can also occur. The condition impinges on every aspect of life, and can make it difficult for sufferers to keep their jobs as well as personal relationships. There can be accident risks caused by the excessive sleepiness and cataplexy. It is believed to be caused by an interplay between genetic and environmental factors. The risk to first-degree relatives is estimated at 1-2%. Patients with narcolepsy have recently been shown to be deficient in hypocretin, also called orexin, in the cerebrospinal fluid and have a reduction in hipocretin cells in the lateral hypothalamus. The present study characterizes a sample of 23 patients suffering from narcolepsy, of which 15 female and 8 male patients, 44 years-old in average. They had their adaptive efficiency evaluated by R. Simon\'s Adaptive and Operationalised Diagnostic Scale (AODS). Major sleep disorders and their effects on patient\'s life quality were surveyed by Giglio\'s Sleep Questionnaire. Intensity of sleepiness was evaluated through Epworth Sleepiness Scale. Mind functioning dynamics was assessed by Phillips on Test (ORT) obeying psychoanalytic theoretical presuppositions. Up to the moment, results show that: 1) narcolepsy is associated to serious damage to adaptive efficiency, with moderate and severe inefficient adaptation, prevailing in most patients; 2) severe excessive daytime sleepiness, sleep attacks and fractioned nocturnal sleep are frequent in most of patients even when medicated with stimulants; 3) the analysis through ORT showed that these patients presented responses that for most of the time, impede their progress Paranoid-schizoid position defense mechanisms were frequent, with fears of being rejected and abandoned. The Object Relations Test revealed interpersonal links impairment, mainly in group and triangular situations.
523

Purity relative to classes of finitely presented modules

Mehdi, Akeel Ramadan January 2013 (has links)
Any set of finitely presented left modules defines a relative purity for left modules and also apurity for right modules. Purities defined by various classes are compared and investigated,especially in the contexts of modules over semiperfect rings and over tame hereditary, andmore general, finite-dimensional algebras. Connections between the indecomposable relativelypure-injective modules and closure in the full support topology (a refinement of theZiegler spectrum) are described.Duality between left and right modules is used to define the concept of a class of leftmodules and a class of right modules forming an almost dual pair. Definability of suchclasses is investigated, especially in the case that one class is the closure of a set of finitelypresented modules under direct limits. Elementary duality plays an important role here.Given a set of finitely presented modules, the corresponding proper class of relativelypure-exact sequences can be used to define a relative notion of cotorsion pair, which weinvestigate.The results of this thesis unify and extend a wide range of results in the literature.
524

La structure des représentations des algèbres de Temperley-Lieb affines sur la chaîne de spins XXZ

Pinet, Théo 08 1900 (has links)
Ce mémoire révèle la structure des représentations des algèbres de Temperley-Lieb affines aTLN(β) sur les espaces propres CN(q,v,d) (du spin total Sz) des chaînes de spins XXZ périodiques. En particulier, on y démontre que ces représentations, introduites dans Martin/Saleur et Morin-Duchesne/Saint-Aubin, admettent toujours une structure similaire à celle des représentations de Feigin-Fuchs de l’algèbre de Virasoro Vir et que les différentes possibilités, pour la structure d’un Vir-module de Feigin-Fuchs, sont toutes réalisées par un espace propre donné. On introduit aussi une pléthore d’applications aTLN(β)-linéaires entre différents espaces propres en considérant une action naturelle de l’extension de Lusztig LUqsl2 sur les chaînes XXZ périodiques et on caractérise entièrement le noyau ainsi que l’image de ces applications à l’aide de longues suites exactes et d’une décomposition de Clebsch-Gordan généralisée. Finalement, on identifie l’image du morphisme iNd(q,v) défini par Morin-Duchesne/Saint-Aubin et on donne également une nouvelle réalisation explicite pour les couvertures projectives de la catégorie modLUqsl2. / This master’s thesis reveals the structure of the representations of the affine Temperley-Lieb algebras aTLN(β) on the eigenspaces CN(q,v,d) (of the total spin Sz) of the periodic XXZ spin chains. In particular, we show that these representations, introduced by Martin/Saleur and Morin-Duchesne/Saint-Aubin, always admit a structure akin that of the Feigin-Fuchs representations of the Virasoro Vir algebra and that the different possibilities, for the structure of a Feigin-Fuchs Vir-module, are all realized by a given eigenspace. We also give a plethora of aTLN(β)-linear maps between different eigenspaces by considering a natural action of the Lusztig extension LUqsl2 on the periodic XXZ chains and we then fully characterize the kernel and image of these morphisms by means of long exact sequences and a generalized Clebsch-Gordan decomposition. Finally, we explicitly give the image of the intertwiner iNd(q,v) defined by Morin-Duchesne/Saint-Aubin and we also introduce a new explicit realization for the projective covers in the category modLUqsl2.
525

Équidistribution des zéros de sections holomorphes aléatoires par rapport à des mesures modérées / Equidistribution of zeros of random holomorphic sections for moderate measures

Shao, Guokuan 24 June 2016 (has links)
Cette thèse étudie les équidistributions de zéros de sections holomorphesaléatoires de fibrés en droites pour les mesures modérées. Elle consiste en deuxparties.Dans la première partie, nous construisons une famille étendue de mesuressingulières modérées sur des espaces projectifs. Ces mesures sont générées pardes fonctions quasi-plurisousharmoniques avec les potentiels höldériens.Le deuxième partie traite une propriété d' équidistribution dans un contextegénéral. Nous établissons un théorème d'équidistribution dans le cas dequelques fibrés en droites gros munis de métriques singulières. Une vitesse deconvergence précise pour l'équidistribution est obtenue. / This thesis investigates the equidistributions of zeros of random holomorphic sections of line bundles for moderate measures. It consists of two parts. In the first part, we construct a large family of singular moderate measures on projective spaces. These measures are generated by quasi-plurisubharmonic functions with Holder potentials.The second part deals with an equidistribution property in general settings. We establish an equidistribution theorem in the case of several big line bundles endowed with singular metrics. A precise convergence speed for the equidistribution is obtained.
526

Uniform Marker Field na válci / Uniform Marker Field on a Cylinder

Kříž, Radim January 2013 (has links)
This work presents a new extension for Uniform Marker Field, which is able to detect UMF on the cylinder. First part of the text deals with Augmented reality and focuses on systems using markers. It discusses the actual state-of-the-art systems and its possibilities. After that it focuses more deeply on the marker system Uniform marker field and its grayscale variants. Next part of the work describes properties of the cylinder projected in real space. Important properties for detecting are discussed in detail. Then the proposal and description of detection algorithm is presented. Implementation of algorithm is tested and evaluated on the very end of this thesis.
527

Gestaltbegeleidingsprogram ten einde smartiewerk as projeksietegniek in lewensvaardighede met die kind te benut

Van Heerden, S. J. 02 1900 (has links)
Summary in English and Afrikaans / This study focus on a Gestalt guidance programme in order to utilize smartiewerk as projection technique in life skills with children The strategy used in the research was case studies. An in depth literature review guided the study‟s theoretical background. A specific focus on the gestalt therapeutic process and gestalt play therapy as such was given to the study. Further literature reviews on the child and life skills was done. In the completion of this study the researcher made use of case studies. The sample existed of non-probability sampling with criteria for inclusion focusing on the child with emotional distress and some form of loss without coping skills as such. The researcher conducted between seven and eight sessions with the three children. In all three case studies it was evident that smartiewerk as projective technique had value in dealing with life skills. / Hierdie studie is onderneem om „n Gestalt begeleidingsprogram te ontwikkel waarbinne smartiewerk™ as projeksietegniek in lewensvaardighede met kinders benut kan word. Die strategie wat vir die navorsing gevolg is, het gevallestudies behels. Daar is ook „n literatuurstudie onderneem wat spesifiek op die Gestalt-terapeutiese benadering en Gestaltspelterapie gefokus het. Verdere literatuurstudie oor die kind en lewensvaardighede is onderneem. In die uitvoering van hierdie studie is daar drie gevallestudies beskryf en die steekproef het berus op „n nie-waarskynlikheid-doelgerigte steekproeftrekking. Die kriteria vir insluiting tot die studie was kind er swat emosionele nood in die vorm van verlies ervaar en gevolglik nie effektief hul eie balans kon herstel nie. Daar is tussen sewe en agt sessie met hierdie kind ers terapeuties gewerk. In al drie gevalle het dit na vore gekom dat smartiewerk™ as projeksietegniek benuttingswaarde het ten einde lewensvaardighede vir die hantering van disekwilibrium by die kind te herstel. / M. Diac. (Spelterapie)
528

Weighted Composition Operators on Spaces of Analytic Functions

Gomez Orts, Esther 30 May 2022 (has links)
[ES] El objetivo de esta tesis es estudiar distintas propiedades de los operadores de composición ponderados en diferentes espacios ponderados de funciones analíticas. Dado un peso v estrictamente positivo y continuo en el disco complejo, consideramos unos ciertos espacios de Banach de funciones analíticas en el discto complejo. Estos espacios son los conjuntos de las funciones holomorfas en el disco f tales que el supremo, de los z en el disco, de v(z)|f(z)| es finito. También consideramos los espacios de las funciones holorfas f que cumplen que v(z)|f(z)| tiende a cero cuando |z| se acerca a 1. Dada una sucesión de pesos, trabajamos con los espacios formados por las intersecciones y uniones de los espacios de Banach ponderados determinados por los pesos de la sucesión. El espacio resultante de la intersección es un espacio de Fréchet y es el límite proyectivo de los espacios de Banach citados. Este espacio está provisto de la topología del límite proyectivo. El espacio resultante de la unión es un espacio LB (límite de Banach), y es el límite inductivo de los espacios citados, con la topología del límite inductivo. Cuando la sucesión de pesos viene determinada por los pesos (1-|z|)^n con n natural, el espacio resultante de la unión se llama espacio de Korenblum, que también es un límite inductivo. En la tesis estudiamos la continuidad, compacidad e invertibilidad de los operadores de composición ponderados en los espacios descritos arriba. También estudiamos algunas propiedades de su espectro y de su espectro puntual. / [CA] L'objectiu d'aquesta tesi és estudiar distintes propietats dels operadors de composició ponderats en diferents espais ponderats de funcions analítiques. Donat un pes v estrictament positiu i continu en el disc del pla complex, considerem uns certs espais de Banach de funcions analítiques en el disc complex. Aquests espais són els conjunts de les funcions holomorfes en el disc f tals que el suprem, dels z en el disc, de v(z)|f(z)| és finit. També considerem els espai de les funcions que verifiquen que v(z)|f(z)| tendeix a zero quan |z| s'apropa a 1. Donada una successió de pesos, treballem amb els espais formats per les interseccions i unions dels espais de Banach ponderats determinats pels pesos de la successió. L'espai resultant de la intersecció és un espai de Fréchet, i és el límit projectiu dels espais de Banach esmentats. Aquest espai està prove ̈ıt de la topologia del l ́ımit projectiu. L'espai resultant de la unió és un espai LB (límit de Banach), i és el límit inductiu dels espais esmentats, amb la topologia del límit inductiu. Quan la successió de pesos està determinada pels pesos (1-|z|)^n amb n natural, l'espai resultant de la unió s'anomena espai de Korenblum, que també és un límit inductiu. En al tesi estudiem la continu ̈ıtat, , compacitat i invertibilitat de l'operador de composició ponderat en els espais descrits abans. També estudiem algunes propietats del seu espectre i del seu espectre puntual. / [EN] The aim of this thesis is to study some properties of the weighted composition operators on different weighted spaces of analytic functions. Given a weight v strictly positive and continuous on the complex disc, we consider certain Banach spaces of analytic functions on the complex disc. These spaces are the sets of the holomorphic functions on the disc f such that the supremum, when z is in the disc, of v(z)|f(z)| is finite. We also consider the spaces of the holomorphic functions f such that v(z)|f(z)| tends to 0 whenever |z| goes to 1. Given a sequence of weights, we work with the spaces described by the intersection or union of the weighted Banach spaces determined by the weights in the sequence. The space of the intersection is a Fréchet space and it is the projective limit of the mentioned Banach spaces. This space is endowed with the projective limit topology. The space given by the union is an LB-space (limit of Banach), and it is the inductive limit of the mentioned spaces, with the inductive limit topology. When the sequence is given by the weights (1-|z|)^n with n natural, the space of the union is called Korenblum space, which is also an inductive limit. In the thesis we study the continuity, compactness and invertibility of the weighted composition operators on the spaces described above. We also study some properties of the spectrum and point spectrum. / Gomez Orts, E. (2022). Weighted Composition Operators on Spaces of Analytic Functions [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/183028
529

Réalisme pictural : pour une étude anthropo-comparative transculturelle sur l'expérience esthétique / Pictorial realism : for an anthropo-comparative transcultural study on the aesthetic experience

Hwang, Ju-Yeon 01 June 2018 (has links)
Le réalisme pictural peut être conçu, par-delà la pensée ontologique dualiste, comme expérience perceptive cognitive du spectateur d’avoir l’impression de voir le « réel » dans une configuration imagée picturale. Cette impression de réel n’est pas illusoire, mais subjectivement factuelle, sans être nécessairement consciente. Elle pourrait résulter de la facilité perceptive ou de la fluidité opérationnelle du processus perceptif cognitif. Lorsque l’activité perceptive cognitive opérante dans l’expérience du réalisme pictural est régulée par la valence hédonique immanente à cette fluidité opérationnelle sous-jacente à l’impression de réel, cette expérience « subjective » peut être également « esthétique » pour cette autosuffisance fonctionnelle de la « conduite cognitive » du spectateur. Cependant, l’expérience du réalisme pictural comporte une dimension anthropo-transculutrelle, comme on peut le constater notamment dans les récits littéraires des spectateurs coréens du 18e siècle qui illustrent leurs expériences visuelles des peintures occidentales « illusionnistes » réalisées par des missionnaires jésuites à Pékin. La culture est néanmoins opérante dans l’expérience « esthétique » du réalisme pictural. Son effet est double. D’une part, la culture fonctionne comme une des variables de la fonction complexe de l’apprentissage perceptif qui pourrait modifier la dynamique du processus perceptif cognitif ainsi que l’attention perceptive visuelle. D’autre part, elle pourrait opérer un effet dans la valence hédonique globale en participant à la modélisation de l’« affect idéal » distingué de l’« affect effectif ». / The pictorial realism can be conceived, beyond ontological dualistic thought, as beholder’s perceptual cognitive experience to have the impression of seeing the “real” in a picture. This impression or feeling of real is not illusory, but subjectively factual, without being necessarily conscious. It may result from perceptual easiness or from perceptual cognitive processing fluency. When the perceptual cognitive activity working in the pictorial realism experience is regulated by hedonic valence immanent in this processing fluency that underlies the impression of real, this subjective experience can also be “aesthetic” by functional self-sufficiency of beholder’s “cognitive conduct”. However, the experience of pictorial realism contains an anthropo-transcultural dimension, as we can observe especially in the stories written by 18th century Korean beholders, which illustrate their visual experiences of the western “illusionist” paintings produced by jesuit missionary painters in Beijing. Nevertheless, the culture comes into play in the “esthetic experience” of pictorial realism. Its effect is double. On the one hand, the culture acts as one of the variables of the complexe function of perceptual learning which could make difference in the perceptual cognitive processing dynamics and in the visual or perceptual attention. On the other hand, the culture might influence the global state of hedonic valence by participating in the modeling of “ideal affect” distinguished from “actual affect”.
530

Géométrie des variétés de Fano : sous-faisceaux du fibré tangent et diviseur fondamental / Geometry of Fano varieties : subsheaves of the tangent bundle and fundamental divisor

Liu, Jie 26 June 2018 (has links)
Cette thèse est consacrée à l'étude de la géométrie des variétés de Fano complexes en utilisant les propriétés des sous-faisceaux du fibré tangent et la géométrie du diviseur fondamental. Les résultats principaux compris dans ce texte sont : (i) Une généralisation de la conjecture de Hartshorne: une variété lisse projective est isomorphe à un espace projectif si et seulement si son fibré tangent contient un sous-faisceau ample.(ii) Stabilité du fibré tangent des variétés de Fano lisses de nombre de Picard un : à l'aide de théorèmes d'annulation sur les espaces hermitiens symétriques irréductibles de type compact M, nous montrons que pour presque toute intersection complète générale dans M, le fibré tangent est stable. La même méthode nous permet de donner une réponse sur la stabilité de la restriction du fibré tangent de l'intersection complète à une hypersurface générale.(iii) Non-annulation effective pour des variétés de Fano et ses applications : nous étudions la positivité de la seconde classe de Chern des variétés de Fano lisses de nombre de Picard un. Ceci nous permet de montrer un théorème de non-annulation pour les variétés de Fano lisses de dimension n et d'indice n-3. Comme application, nous étudions la géométrie anticanonique des variétés de Fano et nous calculons les constantes de Seshadri des diviseurs anticanoniques des variétés de Fano d'indice grand.(iv) Diviseurs fondamentaux des variétés de Moishezon lisses de dimension trois et de nombre de Picard un : nous montrons l'existence d'un diviseur lisse dans le système fondamental dans certain cas particulier. / This thesis is devoted to the study of complex Fano varieties via the properties of subsheaves of the tangent bundle and the geometry of the fundamental divisor. The main results contained in this text are:(i) A generalization of Hartshorne's conjecture: a projective manifold is isomorphic to a projective space if and only if its tangent bundle contains an ample subsheaf.(ii) Stability of tangent bundles of Fano manifolds with Picard number one: by proving vanishing theorems on the irreducible Hermitian symmetric spaces of compact type M, we establish that the tangent bundles of almost all general complete intersections in M are stable. Moreover, the same method also gives an answer to the problem of stability of the restriction of the tangent bundle of a complete intersection on a general hypersurface.(iii) Effective non-vanishing for Fano varieties and its applications: we study the positivity of the second Chern class of Fano manifolds with Picard number one, this permits us to prove a non-vanishing result for n-dimensional Fano manifolds with index n-3. As an application, we study the anticanonical geometry of Fano varieties and calculate the Seshadri constants of anticanonical divisors of Fano manifolds with large index.(iv) Fundamental divisors of smooth Moishezon threefolds with Picard number one: we prove the existence of a smooth divisor in the fundamental linear system in some special cases.

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