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Amblard, Pierre-Olivier. "Statistiques d'ordre supérieur pour les signaux non gaussiens, non linéaires, non stationnaires." Grenoble INPG, 1994. http://www.theses.fr/1994INPG0002.
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Durant les trente dernieres annees, trois hypotheses fondamentales geraient les theories developpees en traitement du signal: gaussiannite, linearite et stationnarite. Le bien fonde de ces proprietes est verifie dans bon nombre d'applications reelles. Toutefois, certaines situations ne peuvent etre etudiees en utilisant ces proprietes, et toutes ou partie doivent etre ecartees. Ce memoire a pour objet l'etude d'outils adaptes pour la description des signaux non gaussiens, non lineaires et/ou non stationnaires. Dans un premier temps, l'hypothese de gaussiannite est levee, et les statistiques d'ordre superieur a deux pour les signaux non gaussiens a valeurs complexes sont introduites. Nous etudions tout particulierement l'influence de la stationnarite sur ces outils pour arriver aux definitions des multicorrelations et multispectres. Comme non-gaussiannite et non-linearite sont liees, nous etudions ensuite une classe particuliere de systemes non lineaires: les filtres de volterra. Leurs definitions en temps et frequence continus sont rappelees avant de presenter la definition et l'implantation de leurs versions discretes. L'identification de ces systemes en moyenne quadratique est alors appliquee a la methode de soustraction de bruit, etude validee sur des signaux issus d'une experience reelle. Enfin, pour pouvoir traiter des signaux non gaussiens non stationnaires, nous presentons la theorie des representations temps-frequence d'ordre superieur a deux. Cette theorie, developpee d'une facon deductive pour les signaux deterministes, est etendue aux signaux aleatoires. Des discussions sur la complexite des outils obtenus sont menees, et une application a la detection de signaux transitoires est proposee
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Fontenot, Anthony. "Non-Design and the Non-Planned City." Thesis, Princeton University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3597482.
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This study seeks to understand the larger cultural context that gave rise to what is referred to as "non-design," a term designated to denote a particular aesthetic that is characterized by a suspicion of, and/or rejection of, "conscious" design, while embracing various phenomenon that emerge without "intention" or "deliberate human design." The study traces the phenomenon of "non-design" in British and American design culture of the postwar period. The author argues that following Friedrich von Hayek's theories of the "undesigned" nature of social institutions and his concept of a "spontaneous order" of the 1940s, non-design first emerged in design discourse and practice in the early 1950s in England, particularly in the work of certain members of the Independent Group, and by the mid-1960s it gained currency in the United States in the architectural and urban theories of Charles Moore, Robert Venturi and Denise Scott Brown, and particularly in Reyner Banham's writing on American urbanism. While rarely made explicit, this dissertation argues that the concept of non-design played an important role in design and urban debates of the postwar period.
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Schittenkopf, Christian, Georg Dorffner, and Engelbert J. Dockner. "Non-linear versus non-gaussian volatility models." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 1999. http://epub.wu.ac.at/724/1/document.pdf.
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One of the most challenging topics in financial time series analysis is the modeling of conditional variances of asset returns. Although conditional variances are not directly observable there are numerous approaches in the literature to overcome this problem and to predict volatilities on the basis of historical asset returns. The most prominent approach is the class of GARCH models where conditional variances are governed by a linear autoregressive process of past squared returns and variances. Recent research in this field, however, has focused on modeling asymmetries of conditional variances by means of non-linear models. While there is evidence that such an approach improves the fit to empirical asset returns, most non-linear specifications assume conditional normal distributions and ignore the importance of alternative models. Concentrating on the distributional assumptions is, however, essential since asset returns are characterized by excess kurtosis and hence fat tails that cannot be explained by models with suffcient heteroskedasticity. In this paper we take up the issue of returns' distributions and contrast it with the specification of non-linear GARCH models. We use daily returns for the Dow Jones Industrial Average over a large period of time and evaluate the predictive power of different linear and non-linear volatility specifications under alternative distributional assumptions. Our empirical analysis suggests that while non-linearities do play a role in explaining the dynamics of conditional variances, the predictive power of the models does also depend on the distributional assumptions. (author's abstract)Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"
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Villa, Maria Cristina. "L'Italia non vede, non sente, non parla? il cinema italiano della deportazione razziale /." Diss., Restricted to subscribing institutions, 2006. http://proquest.umi.com/pqdweb?did=1362521431&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Thesis (Ph. D.)--UCLA, 2006.Vita. Filmografia generale sul cinema della deportazione razziale-- fiction (leaves 470-481). Filmografia del cinema italiano della deportazione razziale (leaves 482-490). Includes bibliographical references (leaves 491-510).
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McDermott, Elizabeth Clare. "Non-social teaching for non-social learners: a non-social and non-interactive verb-learning paradigm for children with ASD." Thesis, Boston University, 2014. https://hdl.handle.net/2144/21216.
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Thesis (M.S.) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.Children with ASD suffer from language deficits that are in part due to impaired social abilities. In the current study, we test a non-social and noninteractive method for teaching word meanings. If successful, this technique will expand the ways we teach early vocabulary that would shape intervention and improve the quality of life and the future prospects of children with ASD. First, the participants (ages 26.09 - 47.37) listen to a series of transitive or intransitive sentences while watching an unrelated silent animation. These sentence types carry different meanings; transitive verbs describe causative actions, and intransitive verbs describe synchronous actions. Then they are asked to map the verb to meaning by finding the relevant action out of two candidate scenes. We analyze the children’s direction of gaze. The results revealed that children with ASD in this sample who heard transitive sentences in maximally non-social and non-interactive contexts did not show a significant preference for the causative scene in either test condition. Additional data will reveal whether children with ASD can learn from non-social presentation of novel words if given multiple exposures to the test scenes. This work will provide insight into the mechanisms underlying word learning in children with ASD and, if successful, provide the foundation for research into a new kind of non-social intervention that capitalizes on these children’s strengths.
2031-01-01
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Welnetz, Katie. "Non-response and non-respondents in survey research." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0004/NQ41600.pdf.
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Moran, Fidelma. "Non-invasive ventilation in non cystic fibrosis bronchiectasis." Thesis, University of Ulster, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445062.
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Delbourgo, Daniel. "Non-Archimedean L-series at non-ordinary primes." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627094.
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Adigwe, Obi Peter. "Non-medical prescribing in chronic non-malignant pain." Thesis, University of Leeds, 2012. http://etheses.whiterose.ac.uk/12675/.
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Introduction: Chronic non-malignant pain poses considerable risk to patients and the health service but its management is still inadequate. The introduction of prescribing for nurses and pharmacists suggests that non-medical prescribing can improve some important aspects of healthcare services. Aim: To provide new insights and theory regarding how nurses and pharmacists prescribe for chronic pain, together with how the service is perceived by chronic pain patients and to uncover barriers and facilitators encountered when this group is prescribed for. Method: A mixed methods strategy was employed in this study. A grounded theory approach was used to collect data from non-medical prescribers and patients. Non-medical prescribes were then surveyed to confirm the emerging theory and determine barriers and facilitators. Findings: The theory ‘safety and support within the prescribing environment’ explains the relationship that non-medical prescribers have with colleagues, patients and other factors in their prescribing environment in their prescribing for chronic pain. Non-medical prescribers are motivated by various factors and may adopt an innovative or conservative approach in their prescribing. Nurses were more likely to engage in informal mentoring relationships, but were limited by their lack of medication knowledge. Pharmacists were limited by a lack of experience with patients, inaccessibility to formal CPD in paid work time and the threats introduced by concerns around ‘second checking'. Chronic pain patients had strategies to maintain relationships with their prescribers and this relationship influenced the likelihood of considering other measures to cope with their pain. Conclusion: Nurses and pharmacists who qualified as prescribers would be more likely to prescribe for chronic pain if they perceived certain essential elements in their prescribing environment. This theory can facilitate assessment of non-medical prescribers’ support, involvement of patients and the development of resources to encourage prescribing.
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Labat, David. "Non-linéarité et non stationnarité en hydrologie karstique." Toulouse, INPT, 2000. http://www.theses.fr/2000INPT043H.
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Nous nous intéressons dans cette étude à l'analyse du fonctionnement de bassins fortement hétérogènes présentant un réseau souterrain important. Ces bassins dits "karstiques" possèdent de grandes réserves d'eaux de très grande qualité mais demeurent cependant dans la plupart des cas peu ou mal exploités. Cette étude vise principalement à mettre en évidence les principales difficultés de la modélisation de ces bassins hétérogènes et à proposer de nouvelles méthodes d'analyses et de simulations de pluies et de débits de sources. Ces techniques sont ensuite validées sur des données mesurées sur quatre systèmes karstiques des Pyrénées (Ariège) et douze zones situées dans les Causses du Larzac sont analysés dans cette étude. Les séries de pluies et de débits ont été enregistrées à divers pas d'échantillonnage, depuis le pas journalier (sur des périodes de trente ans) jusqu'au pas semi-horaire (sur des périodes de un an environ). Dans une première partie, ce travail a consisté à analyser et mettre en évidence les limitations des modèles de type "boîte noire" dans l'étude de la relation pluie-débits. Ainsi, un modèle linéaire et stationnaire de convolution est proposé et utilisé en identification et simulation. Il est alors mis en évidence que ce modèle statique linéaire ne permet pas de reproduire les évènements extrêmes (crues et étiages). Pour ces raisons, un modèle non linéaire de type Volterra est proposé. Dans une deuxième partie, la non-stationnarité des signaux pluies et débits est mise en évidence par l'introduction d'un nouvel outil d'analyse : l'analyse en ondelettes. Cette transformation permet d'obtenir une vision "temps-échelle" des phénomènes hydrologiques. Celle-ci se décompose en deux méthodes principales : l'analyse en ondelettes continue et l'analyse multirésolution. Une interprétation statistique de ces coefficients en ondelettes est aussi proposé avec l'introduction du spectre global en ondelettes, simple et croisé. L'introduction de ces nouvelles techniques a notamment permis de proposer des interprétations plus fines de la relation pluie-débits. Nous avons ainsi pu mettre en évidence des échelles temporelles caractéristiques dans le fonctionnement de ces systèmes. Dans une dernière partie, deux autres techniques sont introduites afin de préciser le comportement des systèmes karstiques en fonction de ces échelles caractéristiques. Ce sont l'analyse fractale et l'analyse multifractale. Tous les résultats obtenus doivent maintenant être introduits dans les modèles de simulation.
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Zhou, Jianying. "Non-repudiation." Thesis, Royal Holloway, University of London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286077.
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GUALTIERI, MARTINA MARIA MACARENA. "Non Recognition." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2019. http://hdl.handle.net/10281/241155.
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Il non riconoscimento nel diritto internazionale il non riconoscimento presenta diverse questioni che devono essere risolte sia alla luce della sua natura, sia del suo contenuto sia dei suoi effetti. La prassi internazionali offre diversi esempi di non riconoscimento. Il presente lavoro cerca di dare ordine a questa varietà di casi cercando di capire come un’analisi di caso in caso sia l’approccio migliore per riaffermare l’importanza del non riconoscimento. Il fatto che esso presenti un contenuto diverso in base alla situazione non determina la sua non importanza. Esso anzi è uno strumento imprescindibile per garantire la tenuta dell’ordine internazionale.Non-recognition in international law presents several questions that need to be resolved both in the light of its nature, its content and its effects. International practice offers several examples of non-recognition. The present work tries to give order to this variety of cases trying to understand how a case by case analysis is the best approach to reaffirm the importance of non-recognition. The fact that it presents a different content according to the situation which is the object of non-recognition does not determine its irrelevance. In fact, it turns out to be an indispensable tool to guarantee the preservation of the international order.
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Fosséprez, Marc Fosseprez Marc. "Topologie et comportement des circuits non linéaires non réciproques /." [S.l.] : [s.n.], 1988. http://library.epfl.ch/theses/?nr=730.
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Ben, Mahjoub Otman. "Non-local dynamics and intermittency in non-homogeneous flows." Doctoral thesis, Universitat Politècnica de Catalunya, 2000. http://hdl.handle.net/10803/6572.
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.La tesi analitza les dinàmiques no locals i la intermitència en fluids no homogenis i no isotròpics tant en experiments de laboratori com en dades geogràfiques. Després de l'estudi sobre els models que descriuen la intermitència en fluids homogenis i isotròpics, presentem un model per fluids no homogenis i no isotropics. El model es basa en l'anàlisi de la jerarquia de transmissió d'energia. S'utilitza la tècnica de la Extended Self Similarity amb l'objectiu d'estudiar l'escala de lleis de les funcions estructurals de velocitat. Els resultats experimentals de tres tipus de fluids que s'han comparat amb el model per fluids no homogenis i no isotròpics són els següents: turbulència generada per un cilindre en un canal de vent i turbulència generada per una reixa i per un jet en un canal d'aigua. S'analitza la turbulència geogràfica del Delta de l'Ebre i del Knebel Vig i els resultats són comparats amb els del model anteriorment esmentat. La contribució principal és el descobriment d'un paràmetre aparentment relacionat amb la jerarquia de transmissió d'energia en el rang inercial que juga un paper clau en la comprensió de les dinàmiques dels fluids no homogenis.
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The thesis analyze the non-local dynamics and intermittency in non-homogeneous and non-isotropic flows both in the laboratory experiments and geophysical data. After a review on models describing intermittency in homogeneous and isotropic flows, a different model for non-homogeneous and non-isotropic flows is introduced. A model is based on the analysis of the energy transfer hierarchy. The technique of Extended Self Similarity is used to study the scaling laws of the velocity structure functions. Experimental results of three type of flows cylinder wake turbulence in wind tunnel, grid and jet turbulence in water channel are presented and compared with the model. The geophysical turbulence in the Ebro Delta and Knebel Vig are analyzed and the results are compared with the model. The important contribution is the discovery of a new apparently parameter related to the energy transfer hierarchy in the inertial range which plays a key role in the understanding of the dynamics of the non-homogeneous flows.
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Castellví, Fernández Quim. "Non-focal non-thermal electrical methods for cancer treatment." Doctoral thesis, Universitat Pompeu Fabra, 2017. http://hdl.handle.net/10803/586217.
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Most physical ablation modalities for cancer treatment are focal and are based on thermal damage. Despite their regular clinical use as an alternative to surgical resection, their thermal principle of operation entails risks regarding the preservation of neighboring vital structures, such as large vessels, critical ducts or nerves. In addition, being focal, their use is unpractical in cases where multiple nodules are present or tumors are difficult to reach with the applicators.
This thesis explores non-thermal electrical treatments which can be applied in a non-focal manner. Two treatments have been investigated: the first treatment, proposed by others a few years ago, is based on the permanent application of low magnitude alternating electric fields through surface electrodes. Here, this treatment has been in vivo studied to evaluate its efficacy as well as to discern whether it is non-thermally mediated. The second electrical treatment is based on the electroporation phenomenon and targets liver tumor nodules.
Electroporation-based therapies employ brief high magnitude electric fields. These pulsed fields, alone or in combination with chemotherapeutic drugs, are able to kill cells by increasing their membrane permeability. Current electroporation-based therapies for internal tumors are local and are delivered through needle-shaped electrodes. Rather than using needle electrodes to treat liver tumors, here it is explored a novel treatment in which large plate electrodes are used to deliver the field across the whole liver in a non local fashion. The treatment aims at simultaneously destroying all tumors while preserving healthy tissue. Its efficacy is based on selectively enhancing the electric field over the tumors by infusing a solution with high electrical conductivity.
The proposed treatment for liver tumors requires a high performance generator which is not currently available. The work presented here includes the design of a new generator topology able to fulfill the requirements.La majoria del mètodes físics d'ablació tumoral es basen en produir dany tèrmic de manera focalitzada. Tot i ser considerats una alternativa habitual a la resecció quirúrgica, el principi tèrmic de funcionament, comporta un risc per la preservació d'estructures vitals adjacents a la zona de tractament, tals com grans vasos o nervis. A més, el fet de ser focals, fa impracticable la seva aplicació en cas de múltiples nòduls o tumors de difícil accés. Aquesta tesi explora tractaments elèctrics no basats en temperatura, capaços de ser aplicats de manera no focal. S'han investigat dos tractaments: El primer, proposat per altres fa pocs anys, està basat en aplicar permanentment camps elèctrics alterns de baixa magnitud a través d'elèctrodes superficials. Aquí, aquest tractament s'ha estudiat in vivo tant per avaluar la seva eficàcia com per discernir si aquesta resideix en la temperatura. El segon tractament es basa en el fenomen d'electroporació i persegueix el tractament de nòduls hepàtics. En els tractaments basats en electroporació, s’apliquen breus camps elèctrics de gran magnitud per tal de permeabilitzar la membrana cel·lular. Això permet la penetració d’agents quimioterapèutics o produeix directament la mort cel·lular. En lloc d'utilitzar, com és habitual, agulles per tal d'aplicar el tractament, aquí s'explora tractar tot el fetge de forma no localitzada, fent servir grans elèctrodes plans i paral·lels. Utilitzant solucions d'alta conductivitat elèctrica, es pretén magnificar selectivament el camp elèctric sobre els tumors, sent així capaços de destruir tots els tumors i alhora preservar el teixit sà. El tractament proposat per els tumors hepàtics, requereix d'un equip generador actualment no disponible. El presentat treball inclou el disseny d'una nova topologia de generadors capaç de complir amb els requisits.
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Torres, Ledesma César Enrique. "Non linear ellipter equations with non-local regional operators." Tesis, Universidad de Chile, 2013. http://www.repositorio.uchile.cl/handle/2250/115927.
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Doctor en Ciencias de la Ingeniería, Mención Modelación MatemáticaEsta tesis consiste de cinco partes. En la primera parte se considera el problema de Dirichlet lineal y no lineal con una difusi\'on no local regional definido implicitamente por \!\!donde $0< \alpha < 1$, $\rho \in C(\overline)$ y $\lambda dist(x,\partial \Omega) \leq \rho (x) \leq dist(x, \partial \Omega)$ con $\lambda \in (0,1]$, $x\in \Omega$. Haciendo uso del teorema de Lax-Milgran y el Teorema del paso de la monta\~na se demuestra la existencia de soluciones d\'ebiles. En la segunda parte, se considera la ecuaci\'on de Schr\"odinger no lineal con difusi\'on no local regional {\small \begin{eqnarray}\label{Aeq04-} \epsilon^{2\alpha} (-\Delta)_{\rho}^{\alpha}u + u = f(u) \quad \mbox{in}\quad \mathbb{R}^{n},\quad u \in H^{\alpha}(\mathbb{R}^{n}), \end{eqnarray}} \!\!donde $0< \alpha <1$, $\epsilon>0$, $n\geq 2$ y $f:\mathbb{R} \to \mathbb{R}$ es super-lineal y tiene un crecimiento sub-critico. El operador $(-\Delta)_{\rho}^{\alpha}$ es el laplaciano no local regional, con rango de alcance determinado por una funci\'on positiva $\rho \in C(\mathbb{R}^{n}, \mathbb{R}^{+})$ y definido por {\small \begin{eqnarray}\label{Aeq05-} \int_{\mathbb{R}^{n}} \!\!\!\!(-\Delta)_{\rho}^{\alpha} uvdx = \int_{\mathbb{R}^{n}}\!\!\int_{B(0,\rho (x))} \!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\frac{[u(x+z) - u(x)][v(x+z) - v(x)]}{|z|^{n+2\alpha}}dzdx. \end{eqnarray}} \!\!Se prueba la existencia de soluci\'on d\'ebil para (\ref{Aeq04-}) aplicando el Teorema del paso de la monta\~na al funcional $I_{\rho}$ definido en $H_{\rho}^{\alpha}(\mathbb{R}^{n})$, combinado con un argumento de comparaci\'on creado por Rabinowitz. El objetivo principal de la tercera parte es estudiar el comportamiento de concentraci\'on de la soluci\'on d\'ebil de la ecuaci\'on (\ref{Aeq04-}) con $f(s) = s^{p}$, cuando $\epsilon \to 0$. En la cuarta parte se estudia el resultado de simetr\'ia para las soluciones ground state de (\ref{Aeq04-}). Para tal prop\'osito, se combina los rearreglos de funciones con los m\'etodos variacionales. Finalmente, se considera un sistema Hamiltoniano fraccionario {\small \begin{eqnarray}\label{Aeq08-} _{t}D_{\infty}^{\alpha}(_{-\infty}D_{t}^{\alpha}u(t)) + L(t)u(t) = & \nabla W(t,u(t)) \end{eqnarray}} \!\!donde $\alpha \in (1/2,1)$, $t\in \mathbb{R}$, $u\in \mathbb{R}^{n}$, $L\in C(\mathbb{R}, \mathbb{R}^{n\times n})$ es una matriz sim\'etrica positiva definida para todo $t\in \mathbb{R}$, $W\in C^{1}(\mathbb{R} \times \mathbb{R}^{n}, \mathbb{R})$ y $\nabla W (t,u)$ es el gradiente de $W$ en $u$. Se demuestra que (\ref{Aeq08-}) posee al menos una soluci\'on no trivial via el Teorema del paso de la monta\~na.
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Nabti, Abderrazak. "Non linear, non-local evolution equations : theory and application." Thesis, La Rochelle, 2015. http://www.theses.fr/2015LAROS032.
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Cette thèse concerne l’étude qualitative (existence locale, existence globale, explosion en temps fini) de quelques équations de Schrödinger non-linéaires non-locales. Dans le cas où les solutions explosent en temps fini, l’estimation du temps maximal d’existence des solutions sera présentée. Le chapitre 1 concerne l’étude d’une équation de Schrödinger non-linéaire sur RN. On s’intéresse à l’existence locale d’une solution pour toute condition initiale donnée dans L2(RN). De plus, on montre que la norme-L2 de la solution explose en temps fini T < 1. Les démonstrations reposent essentiellement sur le théorème de point fixe de Banach et les estimations de Strichartz, et aussi sur le choix convenable de la fonction test dans la formulation faible du problème. Dans le chapitre 2, on considère une équation de Schrödinger non-linéaire non-locale en temps, et on démontre que les solutions de notre problème explosent en temps fini ; ensuite on obtient des conditions nécessaires d’existence globale. Finalement, on obtient une borne inférieure du temps maximal d’existence de la solution. Le chapitre 3 porte sur la non-existence de solutions d’une équation de Schrödinger non-linéaire posée dans RN. Dans un premier temps, sous certaines conditions sur la donnée initiale, on montre qu’il n’existe pas de solution faible globale ; puis on donne une estimation du temps maximal d’existence de la solution. Enfin, on établit des conditions d’existence locale, ou globale de l’équation considérée. En plus, on généralise les résultats précédents au cas d’un système 2 _ 2. Le dernier chapitre traite une équation de Schrödinger non-linéaire non-locale en temps sur le groupe de Heisenberg H. En utilisant la méthode de la fonction test, on démontre que l’équation n’admet pas de solution faible globale. De plus, on obtient, sous certaines conditions sur les données initiales, une estimation inférieure du temps maximal d’existence de la solutionOur objective in this thesis is to study the existence of local solutions, existence global and blow up of solutions at a finite time to some nonlinear nonlocal Schrödinger equations. In the case when a solution blows-up at a finite time T < 1, we obtain an upper estimate of the life span of solutions. In the first chapter, we consider a nonlinear Schrödinger equation on RN. We first prove local existence of solution for any initial condition in L2 space. Then we prove nonexistence of a nontrivial global weak solution. Furthermore, we prove that the L2-norm of the local intime L2-solution blows up at a finite time. The second chapter is dedicated to study an initial value problem for the nonlocal intime nonlinear Schrödinger equation. Using the test function method, we derive a blow-up result. Then based on integral inequalities, we estimate the life span of blowing-up solutions. In the chapter 3, we prove nonexistence result of a space higher-order nonlinear Schrödinger equation. Then, we obtain an upper bound of the life span of solutions. Furthermore, the necessary conditions for the existence of local or global solutions are provided. Next, we extend our results to the 2 _ 2-system. Our method of proof rests on a judicious choice of the test function in the weak formulation of the equation. Finally, we consider a nonlinear nonlocal in time Schrödinger equation on the Heisenberg group. We prove nonexistence of non-trivial global weak solution of our problem. Furthermore, we give an upper bound of the life span of blowing up solutions
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Deser, Andreas. "Lie algebroids, non-associative structures and non-geometric fluxes." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-160487.
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In the first part of this thesis, basic mathematical and physical concepts are introduced. The notion of a Lie algebroid is reviewed in detail and we explain the generalization of differential geometric structures when the tangent bundle is replaced by a Lie algebroid. In addition, Lie bi-algebroids and Courant algebroids are defined. This branch of mathematics finds its application in deformation quantization, which in string theory is the dynamics of open strings in the presence of a background B-field. We explain how the Moyal-Weyl star product arises for constant background fields and how this can be generalized to arbitrary backgrounds and non-associative products. Non-commutative or even non-associative spaces are expected to play a role also in closed string theory: Starting with a compactification on toroidal backgrounds with non-trivial H-flux, T-duality leads on the one hand to configurations with geometric f-flux, but on the other hand to spaces which are only locally geometric in case of Q-flux, or even non-commutative or non-associative in case of the R-flux. We describe the action of T-duality in detail and review the motivation and structure of non-geometric fluxes. It will turn out, that in the local description of non-geometric backgrounds, a bi-vector $\beta$ is more appropriate than the original B-field.
Based on these foundations, we will describe our results in the second part. On the world-sheet level, we will analyse closed string theory with flat background and constant H-flux. The correct choice of left- and right-moving currents allows for a conformal field theory description of this background up to linear order in the H-flux. It is possible to define tachyon vertex operators and T-duality is implemented as a simple reflection of the right-moving sector. In analogy to the open string case, correlation functions allow to extract information on the algebra of observables on the target space. We observe a non-vanishing three-coordinate correlator and after the application of an odd number of T-dualities, we are able to extract a three-product which has a structure similar to the Moyal-Weyl product.
We then focus on the target space and the local structure of the H-,f-,Q- and R-fluxes. An algebra based on vector fields is proposed, whose structure functions are given by the fluxes and Jacobi-identities allow for the computation of Bianchi-identities. Based on the latter, we give a proof for a special Courant algebroid structure on the generalized tangent bundle $TM \oplus T^*M$, where the fluxes are realized by the commutation relations of a basis of sections.
As was reviewed in the first part of this work, in the description of non-geometric Q- and R-fluxes, the B-field gets replaced by a bi-vector $\beta$, which is supposed to serve as the dual object to B under T-duality. A natural question is about the existence of a differential geometric framework allowing the construction of actions manifestly invariant under coordinate- and gauge transformations, which couple the $\beta$-field to gravity. It turns out that we have to use the language of Lie algebroids to extend differential geometry from the tangent bundle of the target space to its cotangent bundle, equipped with a twisted version of the Koszul-Schouten bracket, to answer this question positively. This construction enables us to formulate covariant derivatives, torsion, curvature and gauge symmetries and culminates in an Einstein-Hilbert action for the metric and $\beta$-field. We observe that this action is related to standard bosonic low energy string theory by a field redefinition, which was discovered by Seiberg and Witten and which we described in detail in the first part. Furthermore it turns out, that the whole construction can be extended to higher order corrections in $\alpha'$ and to the type IIA superstring.
We conclude by giving an outlook on future directions. After clarifying the relation of Lie algebroids to non-geometry, we speculate about the application of Lie algebroid constructions to supersymmetry and the extension to the case of Filippov three-algebroids, which could play a role in M-theory.
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Billson, Duncan Robert. "Advanced non-contacting ultrasonic techniques for non-destructive testing." Thesis, University of Warwick, 1994. http://wrap.warwick.ac.uk/107577/.
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This thesis describes research towards the development of ultrasonic methods to test samples that are difficult to test using conventional techniques, with particular emphasis being given to non-contacting methods. The samples investigated in detail were adhesively bonded structures and zircalloy (a zirconium-niobium alloy). The adhesively bonded structures were investigated ultrasonically using an ultrasonic resonance technique (referred to as ultrasonic spectroscopy) to analyse suitable ultrasonic waveforms. This thesis starts by explaining a new approach to ultrasonic spectroscopy, and then describes a number of transduction techniques (both contacting and non-contacting) that were devised to obtain waveforms suitable for spectroscopic analysis. These including conventional piezoelectric transducers, laser generation of ultrasound, EMAT reception of ultrasound, and a novel couplant-free transducer. Tests were undertaken on a variety of samples under a number of different conditions, with the experimental results comparing well with those predicted by theory. Zircalloy was investigated next in an effort to evaluate non-destructively the concentration of hydride in the alloy. This was performed using velocity-temperature measurements (at temperatures up to 500°C) for both shear and longitudinal waves, and by dilatometry (thermal expansion) measurements. Both sets of tests successfully determined the hydride concentrations of test samples. A separate chapter is devoted to the description of some of the novel transducers developed during the course of this research, including a couplant-free transducer, and several transducers for airborne ultrasound. These transducers were found to operate well, the couplant-free transducer being particularly successful (subsequently finding a number of industrial applications). The final experimental chapter describes the building of both a photoelastic, and a schlieren rig that were used to visualise ultrasound, with the intention of giving an insight into some of the ultrasonic phenomena that were associated with the rest of the work. The results obtained were invaluable in analysing the results from previous chapters.
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de, Cabo Portugal Sebastian. "Non Visuals : Material exploration of non-visual interaction design." Thesis, Umeå universitet, Designhögskolan vid Umeå universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-182466.
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Design is all about visuals, or that is what I have found out during this thesis, from the process materials to the outcome our main entry point to any problem is how will we solve it visually so it’s understandable for the general user. This aspect is problematic in itself due to the fact that we, as humans, understand the world and the things around using all our senses continuously, even though we can forget as visuals are so overpowering. There is a huge opportunity area in exploring our other senses and bringing them back to technology, and this can be seen in works in the past like Tangible Interactions [1] or Natural User Interfaces [2]. But in this moment in time, where all these new technologies like VR/AR and IoT are about to enter our lives and change them forever, this topic is more important than ever. We have already seen what happens when we turn humans into mere machines with some fingers as interactive inputs, and barely any senses to process all the information given to us. Now that these technologies are still young and malleable, we can direct the future to where we want it instead of being guided by the technology itself. To do this we need to reimagine the design process, not reinvent the wheel, but add experts which we currently leave behind and I argue are key to unlock these technologies, experts not only of the technological side of things but on the human side too, like physiotherapists and dancers. Add also people who we never think about when we think of VR like visually impaired users, which could make these technologies inclusive since early on, instead of as an afterthought like we usually do. Not only people, but we also need to add new materials to understand how we use our senses and explore ways that we can understand and explore them differently; like bodystorming and improv theatre because when things aren’t visual, how do you sketch it? A sketch turns into a video about movement. The end result provides a wide breadth of examples of the types of innovations that can come out of using these new design materials, and to open new frontiers. From a VR game with no visuals whatsoever to an AR location based story game, to a home sized multimodal operating system containing several different apps controlled through physical movement. The examples open up the space instead of closing into a single solution. This is just the tip of the iceberg, a hope that others will be inspired by it and continue with this journey that has just started, to guide the future into one that is more technological and at the same time more human than ever before. What we know is that VR does not equate Visual Reality.
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Benitez, Federico. "Non Perturbative Renormalization Group : from equilibrium to non-equilibrium." Paris 6, 2013. http://www.theses.fr/2013PA066009.
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Un grand nombre de problèmes ouverts parmi les plus importants en mécanique statistique sont liés aux systèmes hors de l'équilibre thermique. Dans ce travail, nous utilisons des méthodes de théorie de champs pour étudier certains de ces systèmes. Pour ce faire, nous introduisons une représentation de type théorie de champs pour les systèmes d'intérêt, ainsi que le formalisme spécifique utilisé partout dans ce travail, le groupe de renormalisation non perturbatif (NPRG). Ce formalisme a émergé dans les dernières années comme un moyen très efficace pour étudier les systèmes fortement corrélés, et il a été appliqué avec succès à certains problèmes dans et hors de l'équilibre thermique. Avant de traiter les systèmes qui nous intéressent, nous développons de nouveaux outils et méthodes dans le cadre du NPRG, et nous les testons dans le cas relativement simple d'une théorie de champ scalaire, appartenant à la classe d'universalité d'Ising. Celui ci nous permet d'obtenir la fonction d'échelle du modèle d'Ising en d = 3, sans avoir à fixer aucun paramètre libre. En outre, afin de faire face de manière efficace à la physique des systèmes hors d'équilibre, nous étudions en détail certains aspects formels de leur passage à une représentation de type théorie des champs, ainsi que les équivalences entre les différentes voies possibles pour mettre en oeuvre ce passage. Après ces préliminaires, nous nous concentrons sur les transitions de phase hors d'équilibre dans des systèmes de réaction-diffusion, et en particulier dans la sous-classe connue sous le nom de marches aléatoires avec branchement et annihilation (BARW). Parmi d'autres résultats, nous utilisons le NPRG pour trouver une solution exacte pour un des cas les plus simples de système de réaction-diffusion, connu comme l'annihilation pure. Avec cette solution, nous analysons certaines propriétés des systèmes BARW à bas taux de branchement, en utilisant un développement autour de l'annihilation pure. Ce développement perturbatif, qui est réalisé autour d'un modèle non trivial, nous permet de trouver des résultats exacts pour certaines des plus importantes classes d'universalité de ces systèmesMany of the most important open problems in statistical mechanics are related with systems out of thermal equilibrium. In this work we use field theory methods to study some of these systems. To do so, we first introduce a field theory representation for the systems of interest, as well as the specific formalism to be used throughout, the so-called non perturbative renormalization group (NPRG). This formalism has emerged in the last years as a very efficient way to deal with strongly correlated systems, and has been applied with success to problems both in and out of equilibrium. Before treating the actual systems of interest, we develop some new tools and methods within the NPRG context, and test them in a simple scalar field theory, belonging to the Ising universality class. We are able to obtain results for the momentum-dependent scaling function of the d=3 Ising model, without having to fix any free parameter. Also, in order to tackle in an efficient way the physics of out of equilibrium systems, we study in detail some formal aspects of their passage to a field theory representation, as well as the equivalences between different possible ways to perform this passage. After these preliminaries, we concentrate in out of equilibrium active-to-absorbing phase transitions in reaction-diffusion systems, and in particular in the subclass known as branching and annihilating random walks (BARW). Among other results, we use the NPRG to find an exact solution to any vertex in a simple system, known as pure annihilation. With this, we analyze some properties of BARW at low branching rates, by means of an expansion in the branching rate around pure annihilation. This perturbative expansion, which is performed around a nontrivial model, allows us to find some striking exact results for some of the most important universality classes in these systems
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CARPENTIER, RIOU ANNE-MARIE. "Dix cas de polyarthrite rhumatoide non dr1 non dr4." Lyon 1, 1992. http://www.theses.fr/1992LYO1M233.
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Ghoul, Tej-eddine. "Etude de solutions non globales d’équations d’évolution non linéaires." Paris 13, 2011. http://scbd-sto.univ-paris13.fr/intranet/edgalilee_th_2012_ghoul.pdf.
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Dans ce mémoire, nous nous intéressons au phénomène d’explosion en temps fini de solutions qui changent de signe de l’équation suivante :[. . . ] Ce résultat étend un résultat similaire obtenu par Cazenave, Dickstein, et Weissler [. . . ]In this memory, we study the phenomenon of explosion in finite time for sign changing solution of the following equation : [. . . ] This result extends a similar result of Cazenave, Dickstein, and Weissler [. . . ]
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BECHAH, ABDELHAK. "Systemes elliptiques non lineaires dans des ouverts non bornes." Toulouse 3, 2000. http://www.theses.fr/2000TOU30037.
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Cette these est consacree a l'etude de quelques systemes elliptiques quasilineaires dans des domaines non bornes. Nous nous interessons en particulier a des systemes elliptiques comportant l'operateur p-laplacien qui est defini par pu = div(|*u| p - 2*u). Cet operateur apparait en mecanique des fluides, en mecanique des solides, dans les milieux poreux, ainsi que dans d'autres domaines. La premiere partie de cette these est consacree a l'etude variationnelle d'un systeme derivant d'un potentiel. Nous montrons l'existence des solutions strictement positives dans differents cas : sur-homogene, sous-homogene et critique. Grace a un raisonnement assez semblable a celui utilise par clement, fleckinger, stavrakakis et de thelin pour la simplicite de la valeur propre nous obtenons une condition necessaire et suffisante pour l'existence de la solution strictement positive pour un systeme homogene perturbe par un terme sous-homogene. En meme temps nous montrons que la solution obtenue est unique, enfin, nous employons des methodes iteratives dues a serrin pour etablir des estimations locales et globales de la solution. L'objet de la seconde partie est l'etude non variationnelle d'un systeme homogene. Nous nous interessons en particulier a la methode du blow up introduite par gidas et spruck qui nous permet d'utiliser le theoreme du degre topologique de leray schauder et d'obtenir l'existence des solutions classiques.
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Rhomari, Noureddine. "Filtrage non parametrique pour les processus non markoviens. Applications." Paris 6, 1994. http://www.theses.fr/1994PA066246.
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Un important probleme, qui n'a pas ete largement discute, dans l'etude et l'analyse des processus est l'estimation des valeurs manquantes, qui pour certaines raisons ne peuvent pas etre observees ou sont aberrantes. Un interpolateur similaire aux predicteurs est etudie. D'autre part les predicteurs non parametriques usuels consistent a estimer l'esperance conditionnelle de la variable a predire connaissant un nombre fini des dernieres variables observees. Ce qui suppose que la memoire du processus est de taille finie et connue, donc le processus est markovien. Cette hypothese est tres restrictive. De plus en pratique le choix de cette taille depend, souvent, du nombre d'observations. Dans ce travail on s'interesse a l'estimation non parametrique de ces interpolateur et predicteur, en choisissant la longueur de la memoire dependante du nombre d'observations. Dans le cadre des processus melangeants nous etablissons la consistance et la loi asymptotique des estimateurs proposes. Des resultats sont egalement obtenus pour des fonctionnelles de l'erreur de prediction ou d'interpolation. On etudie, en particulier, ses moments centres, ses fonctions de repartition et de quantile. Ce travail permet donc de proposer un choix de la taille de la memoire, lorsque celle-ci n'est pas connue (ou infinie) a priori. On propose un critere de detection de valeurs aberrantes
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Henry, Marie-Louise. "Non-thyroid malignancies in familial non-medullary thyroid cancer." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555088063551251.
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RUGGIERI, SOPHIE. "Traitement des cancers du poumon non anaplasiques, non resecables, non metastatiques : a propos de 505 cas." Angers, 1989. http://www.theses.fr/1989ANGE1084.
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Chikhi, Mohamed. "Modélisation non paramétrique des processus stochastiques : analyse non paramétrique de la non linéarité de l'indice CAC40." Montpellier 1, 2001. http://www.theses.fr/2001MON10024.
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Dans ce travail, nous nous intéressons à la modélisation dynamique non paramétrique des processus stochastiques. Nous tentons de dépasser la vision traditionnelle traitant les fluctuations observées sur le marché boursier parisien en cherchant à identifier la série de l'indice CAC 40 tout en tenant compte de la méthode du noyau. Dans le chapitre 1, nous précisons la théorie de l'efficience informationnelle des marchés boursiers en distinguant les trois catégories usuelles de l'efficience et étudions les anomalies sur les marchés boursiers. Au chapitre 2, nous testons l'hypothèse d'efficience au sens faible par le biais de divers tests classiques de marché aléatoire et d'autocorrélation. Ensuite, nous appliquons deux tests non paramétriques plus puissants : le test de Mizrach et le test de BDS. Dans un dernier temps, nous testons s'il existe un type de dépendance à long terme en testant le coefficient d'intégration fractionnaire et la mémoire longue. Le chapitre 3 présente des résultats théoriques concernant les prédicteurs non paramétriques et la méthode du noyau. Au chapitre 4, l'étude est consacrée à une mise en œuvre pratique des processus autorégressifs fonctionnels et l'analyse de la volatilité des rendements boursiers avec la présence d'un effet ARCH non paramétrique qu fournit une estimation du risque. Plus spécifiquement, nous nous attachons à déterminer si le modèle NAR-ARCH non paramétrique peut battre la marche aléatoireIn this work, we are interested in the nonparametric dynamic modelling of the stochastic processes. We try to exceed the traditional vision treating the observed fluctuations on the Parisian stock exchange market while seeking to identify the stock exchange CAC 40 series while holding account of the kernel method. In chapter 1, we specify the informational efficiency theory of the stock exchange markets by distinguishing the three usual categories of efficiency and study the anomalies in the stock exchange markets. In chapter 2, we test the weak from efficiency hypothesis by the various traditional tests of random walk and autocorrelation. Then, we apply two more powerful nonparametric tests : Mizrach and BDS tests. In a last time, we test if there is a type of long-term dependence by testing the fractional coefficient of integration and the long memory. .
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Beaulieu, Frédéric. "Réduction non-linéaire du bruit et détection de non-stationnarité." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ53921.pdf.
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Harursampath, Dineshkumar. "Non-classical non-linear effects in thin-walled composite beams." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/12501.
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El, Ouafdi Ahmed Fouad. "Méthodes primales-duales pour la programmation non linéaire non convexe." Mémoire, Université de Sherbrooke, 2003. http://savoirs.usherbrooke.ca/handle/11143/4589.
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La modélisation sous forme de systèmes non linéaires avec ou sans contrainte apparaît régulièrement dans les problèmes de mathématiques appliqués en optimisation. Dans ce mémoire, nous décrivons en premier lieu le principe de base de certaines méthodes de résolution de problèmes d'optimisation dans le cas non linéaire. La différence principale entre ces méthodes se situe au niveau de la technique de globalisation adoptée, à savoir la technique de région de confiance ou la technique de recherche linéaire. Les deux approches de globalisation utilisent des fonctions de mérite ou un filtre pour renforcer la convergence globale vers des points critiques. Nous établissons ensuite un cadre général qui permet de calculer la direction de recherche pour ces méthodes. Enfin, nous présentons un algorithme primal-dual de pénalité mixte qui utilise la technique de globalisation de recherche linéaire et une fonction de mérite primale-duale pour renforcer la convergence globale vers un point stationnaire de première ordre.
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Holmes, Dale Christopher. "Abstract realism : non-anthropocentric strategies for constructing non-relational artworks." Thesis, Sheffield Hallam University, 2013. http://shura.shu.ac.uk/19821/.
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This thesis investigates the neighbourhoods of artistic abstraction and philosophical realism towards developing a new material philosophy and practice led research methodology based upon a series of 'non-anthropocentric strategies' (following Fredric Jameson) for constructing, staging and encountering artworks as 'non-relational' (following Francois Laruelle) 'totalities' (following Carl Einstein) within the cultural-economic-socio-political reality of'capitalist realism' (following Mark Fisher).The thesis is presented over two 'sectors'. Each sector demonstrates the practical application of the material philosophy of abstract realism; investigating the nonrelational, construction and spatial claims of the research. The first sector is the written text titled An Asymmetrical and Angular Architectonic Arrangement. This sector gathers together eleven distinct 'zones' of research activity that have been carried out across the period of this project. The second sector is a new original artwork constructed using the 'toolkit' of abstract realism, titled 'Blackplastic.' This project concludes by proposing a number of contributions; first, a re-orientation of Jencksian adhocism away from any idealisms of'openness' and the 'whole' (Jencks) towards a focus on its practical application and constructive methodology, second, the development of the method 'glossary' as a contemporary anti-razor, third, the claim that the application of abstract realism to the curation and staging of artworks leads to asymmetrical encounters, fourth, the transferability of abstract realism beyond fine art studio practice. These are followed by the main contribution to knowledge which encapsulates the above and asserts that abstract realism is a re-positioned artistic abstraction; a non-representational material philosophy in itself and a new methodology for practice led research. The project culminates with a manifesto for abstract realism.
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Ireka, Ikenna Ebubechukwu. "Computational analysis of non-isothermal flow of non-Newtonian fluids." Doctoral thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/15590.
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The dynamics of complex fluids under various conditions is a model problem in bio-fluidics and in process industries. We investigate a class of such fluids and flows under conditions of heat and/or mass transfer. Experiments have shown that under certain flow conditions, some complex fluids (e.g. worm-like micellar solutions and some polymeric fluids) exhibit flow instabilities such as the emergence of regions of different shear rates (shear bands) within the flow field. It has also been observed that the reacting mixture in reaction injection molding of polymeric foams undergoes self-expansion with evolution of heat due to exothermic chemical reaction. These experimental observations form the foundation of this thesis. We explore the heat and mass transfer effects in various relevant flow problems of complex fluids. In each case, we construct adequate mathematical models capable of describing the experimentally observed flow phenomena. The mathematical models are inherently intractable to analytical treatment, being nonlinear coupled systems of time dependent partial differential equations. We therefore develop computational solutions for the model problems. Depending on geometrical or mathematical complexity, finite difference or finite volume methods will be adopted. We present the results from our numerical simulations via graphical illustrations and validate them (qualitatively) against' similar' results in the literature; the quotes being necessary in keeping in mind the novelties introduced in our investigations which are otherwise absent in the existing literature. In the case where experimental data is available, we validate our numerical simulations against such experimental results.
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Chang, Richard. "Etude des réseaux de caméras non synchronisées ou non calibrées." Paris 6, 2009. http://www.theses.fr/2009PA066024.
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Les systèmes de vision multi-caméras sont de plus en plus utilisées afin notamment de couvrir des scènes larges. La multiplication du nombre de capteurs introduit alors de nouvelles contraintes pour les traitements de vision par ordinateur. Les réseaux de caméras sont généralement considérés comme une simple combinaison des données provenant de capteurs. Notre approche permet d’exploiter le réseau comme un capteur unique. Une méthode de synchronisation entre les images des séquences, basée un objet non-déformable de la scène, est présentée. L’utilisation d’un vocabulaire commun entre les caméras permet de déterminer la topologie globale du réseau. Une nouvelle représentation des caméras simplifie la gestion du réseau en le réduisant à différentes informations codifiées. Cette représentation est calculée à partir d'une structure multi-couches permettant d’extraire les informations principales et de caractériser la trajectoire des objets de la scène.
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Mouzaoui, Lounès. "Régimes asymptotiques pour l'équation de Schrödinger non linéaire non locale." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20241/document.
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Cette thèse est consacrée à l'étude de quelques régimes asymptotiques de l'équation de Schrödinger semi-classique, en présence d'une non-linéarité non-locale de type Hartree. Elle comporte 3 parties, sous forme de 4 chapitres et une annexe. L'objet de la première partie, constituée du premier et deuxième chapitre, est l'étude du comportement asymptotique du modèle précédent pour un noyau singulier autour de l'origine, pour une condition initiale asymptotiquement de type WKB, en régime faiblement non-linéaire. Dans le premier chapitre nous montrons que sous certaines conditions de régularité sur la condition initiale, la solution est encore de type WKB à l'ordre principal, un résultat que nous obtenons dans le cadre fonctionnel de l'algèbre de Wiener. Nous donnons une preuve alternative au résultat précédent dans le cas particulier de l'équation de Schrödinger-Poisson dans le cadre fonctionnel d'espace de Sobolev rescalé, où la considération de correcteurs est nécessaire pour construire une solution approchée et pouvoir décrire la solution à l'ordre principal. La deuxième partie de cette thèse, objet du troisième chapitre, est consacrée à l'étude de la propagation de paquets d'onde pour un système couplé d'équations de Hartree en régime semi-classique, en présence de potentiels extérieurs sous-quadratiques. Nous décrivons analytiquement et numériquement le comportement asymptotique à l'ordre principal des fonctions d'onde solution du système, lorsqu'elles sont soumises à une condition initiale en forme de paquets d'onde, pour différentes tailles de non-linéarité. La dernière partie est constituée du quatrième chapitre et de l'annexe. Dans le quatrième chapitre nous considérons le problème de Cauchy de l'équation de Hartree avec noyau homogène ou dont la transformée de Fourier est dans un espace de Lebesgue, dans le cadre fonctionnel de l'algèbre de Wiener. Nous montrons quelques résultats sur le caractère bien posé du problème pour les noyaux considérés, dans des espaces faisant intervenir l'algèbre de Wiener. Nous concluons par une annexe dans laquelle nous considérons le problème de Cauchy de l'équation de Schrödinger-Poisson, en présence d'un potentiel extérieur indépendant du temps, dans les espaces de Sobolev pondérés. Nous étendons des résultats déjà obtenus sur l'existence de solutions globales dans les espaces de Sobolev sans poids lorsque le potentiel extérieur est nul, en montrant l'existence de solutions globales en temps dans les espaces de Sobolev pondérés pour toute régularitéThis thesis is devoted to the study of some asymptotic regimes of the semi-classical Schrödinger equation, in the presence of a nonlocal nonlinearity of Hartree-type . The purpose of the first part, consisting of the first and second chapter is the study of the asymptotic behavior of the previous model with a singular kernel around the origin for an initial data asymptotically of WKB-type, in a weakly nonlinear regime. In the first chapter we show that under some regularity conditions on the initial data, the solution still is of WKB-type at leading order, a result that we get in the functional framework of the Wiener algebra . We give an alternative proof to the previous result in the particular case of the Schrödinger-Poisson equation in the functional framework of rescaled Sobolev space, where the consideration of correctors is necessary to construct an approximate solution to describe the solution at leading order.The second part of this thesis, the subject of the third chapter is devoted to the study the propagation of wave packets for a coupled system of Hartree equations in a semi-classical regime , in the presence of sub-quadratic external potentials. We describe analytically and numerically the asymptotic behavior of the leading order of the wave functions solution of the system, for an initial data in the form of wave packets for different sizes of nonlinearity.The final part consists of the fourth chapter and appendix.In the fourth chapter we consider the Cauchy problem of the Hartree equation with a homogeneous kernel or of Fourier transform in a Lebesgue space, in the functional framework of the Wiener algebra. We show some results on the well-posedness of the problem for the considered kernels, in spaces involving the Wiener algebra.We conclude with an appendix in which we consider the Cauchy problem for the Schrödinger-Poisson equation in the presence of a time independent external potential in the weighted Sobolev spaces. We extend the results already obtained on the existence of global solutions in Sobolev spaces without weight when the external potential is reduced to zero, by showing the existence of global solutions in time in the weighted Sobolev spaces for all regularity
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El, Ouafdi Ahmed Fouad. "Méthodes primales-duales pour la programmation non linéaire non convexe." Sherbrooke : Université de Sherbrooke, 2003.
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Pechenik, Leonid. "Pattern formation and non-linear dynamics of non-equilibrium systems /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9970653.
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Alshaalan, Rasha. "Non-invasive diagnostic methods for non-alcoholic fatty liver disease." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119567.
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Background: NAFLD is one of the most common causes of liver disease worldwide. It is a spectrum of disease characterized by macrovesicular steatosis of the liver that ranges from simple fatty liver (steatosis), to non-alcoholic steatohepatitis (NASH). NASH may eventually evolve to cirrhosis and end stage complication. Liver biopsy has long been considered the gold standard of reference to diagnose NAFLD but it is costly and invasive. Recently, non-invasive methods have been proposed. Aims and methods: The aim of this study was to investigate the accuracy of non-invasive methods including (Ultrasound, computed tomography scan, Xenon-133 scan, Hepatic steatosis index, Fibroscan, NAFLD fibrosis score, APRI index, and FIB-4 index) and their combination to diagnose steatosis and to diagnose significant liver fibrosis (>F2) and cirrhosis (F4) as compared to liver biopsy. We conducted a retrospective study of 114 NASH patients (79 males, mean age 49.6±10.6). All had adequate liver histology. Results: The distribution of fibrosis stage was as follows: F0-F1= 50%, F2=16.8%, F3=19.2%, F4=14%. The distribution of steatosis grade was as follows: grade 0-1=16%, grade2=53.3%, grade3=30.7%. The following tests correlated with fibrosis: APRI index (r=0.554), FIB-4(r=0.555), NAFLD fibrosis score (r=0.473), Fibroscan(r=0.586) and Hepatic Steatosis Index (HSI) (r=0.245). The FIB-4 and APRI index showed the best diagnostic accuracy for significant fibrosis as indicated by an Area Under the Curve (AUC) of 0.801 and 0.782, respectively. The FIB-4 showed the best AUC= 0.886 for cirrhosis. None of the following tests US, CT, HSI, and xenon-133 scan were considered correlated significantly. The best combination algorithm for the detection of cirrhosis was gender and FIB-4 with an AUC of 0.8937. Conclusion: this study demonstrates that non-invasive methods for liver fibrosis are accurate to diagnose >F2 and F4. Severe steatosis cannot be reliably diagnosed by non-invasive methods. Notably, a combination of FIB-4 and gender significantly improves the performance of the single method for cirrhosis. These methods may help reducing the number of liver biopsies stratifying NASH patients that should start a screening program for HCC and esophageal varices.Contexte : La stéatose hépatique non alcoolique (SHNA) est l'une des causes les plus répandues des maladies du foie à l'échelle mondiale. Il s'agit d'un spectre de maladies qui se caractérise par une stéatose hépatique macrovésiculaire allant de la stéatose hépatique simple (stéatose) à la stéatohépatite non alcoolique (NASH). La NASH peut éventuellement évoluer vers une cirrhose et des complications en phase terminale. La biopsie du foie a longtemps été considérée comme la norme de référence par excellence pour le diagnostic de la SHNA, mais elle est coûteuse et invasive. Des méthodes non invasives ont récemment été proposées. Objectifs et méthodes : La présente étude avait pour objectif d'évaluer la précision de certaines méthodes non invasives (notamment les ultrasons [US], la tomographie par ordinateur [TO], la scintigraphie au xénon 133, l'indice de stéatose hépatique (ISH), la technique Fibroscan, le score de fibrose de SHNA, l'indice de ratio entre l'aspartate aminotransférase et les plaquettes [APRI] et l'indice FIB-4) et de l'utilisation combinée de ces méthodes pour le diagnostic de la stéatose et pour le diagnostic d'une fibrose hépatique significative (> F2) et de la cirrhose (F4), par comparaison à la biopsie du foie. Nous avons réalisé une étude rétrospective sur 114 patients atteints de NASH (79 patients de sexe masculin, âge moyen de 49,6 ans ± 10,6). Tous ces patients présentaient une histologie hépatique adéquate.Résultats : La répartition des stades de fibrose était la suivante : F0 F1 = 50 %, F2 = 16,8%, F3 = 19,2 %, F4 = 14 %. La répartition des stades de stéatose était la suivante : stade 0-1 = 16 %, stade 2 = 53,3 %, stade 3 = 30,7 %. Les tests suivants ont été mis en corrélation avec la fibrose : l'indice APRI (r = 0,554), l'indice FIB-4 (r = 0,555), le score de fibrose de SHNA (r = 0,473), la technique Fibroscan (r = 0,586) et l'indice de stéatose hépatique (r = 0,245). L'indice FIB-4 et l'indice APRI ont offert la meilleure précision diagnostique en ce qui concerne la fibrose significative, comme l'indiquent la surface sous la courbe (SSC) de 0,801 et la SSC de 0,782 respectivement. L'indice FIB-4 a présenté la meilleure SSC, soit 0,886, pour ce qui est de la cirrhose. Aucun des tests suivants, c'est à dire les tests aux US, la TO, l'ISH, et la scintigraphie au xénon 133, n'était considéré comme étant corrélé significativement. Le meilleur algorithme de combinaison pour le dépistage de la cirrhose était le sexe et l'indice FIB-4 avec une surface sous la courbe de 0,8937. Conclusion: cette étude démontre que les méthodes non invasives de diagnostic de la fibrose hépatique sont précises en ce qui concerne les stades > F2 et F4. La Stéatose sévère ne peut être diagnostiqué de façon fiable par des méthodes non invasives Notamment, une combinaison de l'indice FIB-4 et du sexe améliore considérablement le rendement de la méthode unique en ce qui a trait à la cirrhose. Ces méthodes pourraient aider à réduire le nombre de biopsies du foie visant à stratifier les patients atteints de NASH qui devraient entreprendre un programme de dépistage du carcinome hépatocellulaire (CHC) et des varices œsophagiennes.
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Ltaief, Ali. "Synthèse d'observateurs pour les systèmes non linéaires, non uniformément observables." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMC211/document.
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Les résultats présentés dans cette thèse s’articulent autour de la synthèse d’observateurs de type grand gain pour des classes de systèmes non linéaires multi-entrées, multi-sorties non uniformément observables. Dans un premier temps, la classe de systèmes considérées est telle que la dynamique des variables d’état est décrite par la somme de deux termes. Le premier correspond à une partie affine en l’état décrite par le produit d’une matrice, dont les entrées (fonctions non linéaires de l’état) ont une structure triangulaire, par le vecteur d’état. Le deuxième terme est composé par les non linéarités du système qui ont aussi une structure triangulaire. Le gain de l’observateur proposé est issu de la résolution d’une équation différentielle ordinaire de type Lyapunov.La convergence exponentielle de l’erreur d’observation sous-jacente est établie sous une une certaine condition d’excitation persistante dépendant de l’entrée du système et de l’état de l’observateur.Dans un deuxième temps, la synthèse de cet observateur est étendue à une classe plus large de systèmes non linéaires où des états peuvent intervenir de manière non triangulaire.La notion d’indices caractéristiques associés à ces états est alors introduite et elle a permis de définir une structure triangulaire étendue pour la quelle la synthèse de l’observateur a aussi été effectuée.Enfin, il a été établi que les observateurs proposés peuvent être utiliséscomme observateurs adaptatifs pour l’estimation simultanée de l’état et de certains paramètres et une forme adaptative de ces observateurs a été générée.Les performances des différents observateurs proposés ont été illustrées à travers des exemples en simulationThe results given in this thesis deal with the design of high gain observers for some classes on Multi Input Multi Output non uniformly observable nonlinear systems. In a first step, the class of considered systems is such that the dynamics of the state variables is the sum of two terms. The first term is affine in the state and is composed by the product of a matrix, whose entries are nonlinear functions of the state with a triangular structure, by the state vector. The second term describes the system nonlinearities which also assume a triangular structure. The gain of the proposed observer is issued from the resolution of a Lyapunov ordinary differential equation. The exponential convergence of the underlying observation error is established under a persistent excitation condition involving the system inputs and the state of the observer. In a second step, the observer design has been extended to a larger class of nonlinear systems where some state variables may intervene in a non triangular way. The notion of the characteristic indices associated to these state variables is then introduced and it allowed to define an extended triangular structure for which a high gain observer has been designed. Finally, it has been established that the proposed observers can be used as adaptive ones to jointly estimate the system state together with some unknown parameters and an adaptive form of these observers has been derived. The performance and main properties of the proposed observers have been illustrated in simulation by considering many examples throughout this thesis
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Frazer, Gordon John. "Aspects of time-varying non Gaussian non-linear signal analysis." Thesis, Queensland University of Technology, 1996. https://eprints.qut.edu.au/105546/1/T%28BE%26E%29%201032%20Aspects%20of%20time-varying%20non-Gaussian%20non-linear%20signal%20analysis.pdf.
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This thesis addresses problems in the field of time-varying, non-Gaussian, non-linear signal processing. It concentrates on developing results in the areas of time-frequency signal analysis and higher-order spectra which are linked by the developing area of time-varying higher-order spectra. Motivation comes from applying procedures developed to underwater acoustic signals. Reviews of time-frequency analysis and higher-order spectra precede the research contributions. Three appendices cover: a review of the
multiple-window spectrum estimation method, an improved procedure for computing analytic signals frequently used in time-frequency signal analysis, and an updated approach for computing Slepian sequences necessary for the multiple-window spectrogram.
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Gondek, David. "Non-redundant clustering /." View online version; access limited to Brown University users, 2005. http://wwwlib.umi.com/dissertations/fullcit/3174612.
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Pop, Cristina-Maria. "Non-equilibrium relaxation." Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-151719.
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Ross, Skyler W. "Non-Euclidean Geometry." Fogler Library, University of Maine, 2000. http://www.library.umaine.edu/theses/pdf/RossSW2000.pdf.
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Dowrick, Nigel. "Non-peturbative QCD." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236231.
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Jones, Claire. "Probabilistic non-determinism." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/413.
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Much of theoretical computer science is based on use of inductive complete partially ordered sets (or ipos). The aim of this thesis is to extend this successful theory to make it applicable to probabilistic computations. The method is to construct a "probabilistic powerdomain" on any ipo to represent the outcome of a probabilistic program which has outputs in the original ipo. In this thesis it is shown that evaluations (functions which assign a probability to open sets with various conditions) form such a powerdomain. Further, the powerdomain is a monadic functor on the categoy Ipo. For restricted classes of ipos a powerdomain of probability distributions, or measures which only take values less than one, has been constructed (by Saheb-Djahromi). In the thesis we show that this powerdomain may be constructed for continuous ipos where it is isomorphic to that of evaluations. The powerdomain of evaluations is shown to have a simple Stone type duality between it and sets of upper continuous functions. This is then used to give a Hoare style logic for an imperative probabilistic language, which is the dual of the probabilistic semantics. Finally the powerdomain is used to give a denotational semantics of a probabilistic metalanguage which is an extension of Moggi's lambda-c-calculus for the powerdomain monad. This semantics is then shown to be equivalent to an operational semantics.
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Stainton, Robert James Harold. "Non-sentential assertions." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12501.
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Egan, Andrew M. (Andrew Michael) 1970. "Non-standard features." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/30114.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Linguistics and Philosophy, February 2004.Includes bibliographical references (p. 107-109).
The dissertation is composed of three papers on properties and their relatives. "Second-Order Predication and the Metaphysics of Properties" argues that giving a happy account of second-order predication motivates us to identify properties with functions from
by Andrew M. Egan.
Ph.D.
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Sequeiros, Víctor Agustín. "Non omnis moriar." Doctoral thesis, Universidad Nacional de Cuyo. Facultad de Filosofía y Letras, 2011. http://bdigital.uncu.edu.ar/9196.
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Lin, Shang-Hsiang, and 林上襄. "non." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/83096482275931265937.
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Liao, Kae-hung, and 廖啟宏. "non." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/72636715899115304920.
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