Le récit enchâssé émerge comme concept au début du XXe siècle, à la faveur des travaux formalistes sur le recueil de nouvelles. Il ne se développe véritablement que dans les années soixante, sous la plume de Todorov et de Genette. Mais alors, il est moins étudié qu’effleuré. Aucune définition consensuelle ne se dégage chez les narratologues. On prête au dispositif une origine millénaire, sans bien expliquer la persistance intacte d'un procédé d'écriture depuis l'Inde ancienne. Le récit enchâssé a été davantage un mythe critique qu'un objet d'étude. Cette thèse se propose de reprendre la conceptualisation là où elle s'est arrêtée : à l'intuition que certains textes contiennent des récits en surplus. Par des décrochages typographiques, par un changement d'énonciateur, par une variation temporelle, par une série de marquages spécifiques, un récit peut être mis en relief dans l'espace textuel. L'enchâssement, alors, ne serait que le fait de cette mise en relief, qu'elle s'effectue ou non dans un texte littéraire, qu'elle porte ou non sur un texte narratif. Y a-t-il légitimité, dès lors, à parler d'un « récit enchâssé » ? A-t-il existé dans l'histoire une technique homogène de mise en relief d'un récit ? En posant cette question sur les récits courts du XIXe siècle (1800-1890), cette thèse s'efforce également d'expliquer l'apparition de la notion. Car c'est au XIXe siècle que, pour la première fois, le recueil de nouvelles est comparé à une fiction indépendante, en l'occurrence, une nouvelle. Analyser ce rapprochement permet de découvrir comment a été préparée la possibilité de penser le « récit enchâssé ». / At the beginning of the twentieth century, embedded narrative emerged as a concept, thanks to the research that Russian formalists had carried out on a collection of short stories. But the category came into bloom only in the 1960s, under Todorov and Genette's pens. At that time though, the subject was broached rather than dealt with in depth. No definition based on consensus ever arose from narratology; and the seamless persistence of this narrative technique, dating back to Ancient India, has never been well accounted for. Embedded narrative has always been a critical myth rather than a subject to be studied. The aim of this dissertation is to start where the first tentative conceptualization stopped: the feeling that some texts do contain extra narratives. Inserted stories can be enhanced through typography layouts, changes of narratee, time-related alterations, or by sets of specific markings. Embedding might then mean emphasizing rather than inserting. Is it then legitimate to comment on 'embedded narratives' as such? Was there ever a consistent technique to emphasize narratives? By raising these issues, this dissertation aims at getting to the root of the notion, and addresses the topic by drawing on a large number of short stories published between 1800 and 1890. For during the nineteenth century short stories collections came for the first time closer to independent fiction, precisely to short story. Analyzing this rapprochement will enable us to discover how the very notion of 'embedded narrative’ could come up.

Diese Dissertation präsentiert neue Techniken der Integration für verschiedene Probleme der Finanzmathematik und einige Anwendungen in der Wahrscheinlichkeitstheorie. Zu Beginn entwickeln wir zwei Zugänge zur robusten stochastischen Integration. Der erste, ähnlich der Ito’schen Integration, basiert auf einer Topologie, erzeugt durch ein äußeres Maß, gegeben durch einen minimalen Superreplikationspreis. Der zweite gründet auf der Integrationtheorie für rauhe Pfade. Wir zeigen, dass das entsprechende Integral als Grenzwert von nicht antizipierenden Riemannsummen existiert und dass sich jedem "typischen Preispfad" ein rauher Pfad im Ito’schen Sinne zuordnen lässt. Für eindimensionale "typische Preispfade" wird sogar gezeigt, dass sie Hölder-stetige Lokalzeiten besitzen. Zudem erhalten wir Verallgemeinerungen von Föllmer’s pfadweiser Ito-Formel. Die Integrationstheorie für rauhe Pfade kann mit dem Konzept der kontrollierten Pfade und einer Topologie, welche die Information der Levy-Fläche enthält, entwickelt werden. Deshalb untersuchen wir hinreichende Bedingungen an die Kontrollstruktur für die Existenz der Levy-Fläche. Dies führt uns zur Untersuchung von Föllmer’s Ito-Formel aus der Sicht kontrollierter Pfade. Para-kontrollierte Distributionen, kürzlich von Gubinelli, Imkeller und Perkowski eingeführt, erweitern die Theorie rauher Pfade auf den Bereich von mehr-dimensionale Parameter. Wir verallgemeinern diesen Ansatz von Hölder’schen auf Besov-Räume, um rauhe Differentialgleichungen zu lösen, und wenden die Ergebnisse auf stochastische Differentialgleichungen an. Zum Schluß betrachten wir stark gekoppelte Systeme von stochastischen Vorwärts-Rückwärts-Differentialgleichungen (FBSDEs) und erweitern die Theorie der Existenz, Eindeutigkeit und Regularität der sogenannten Entkopplungsfelder auf Markovsche FBSDEs mit lokal Lipschitz-stetigen Koeffizienten. Als Anwendung wird das Skorokhodsche Einbettungsproblem für Gaußsche Prozesse mit nichtlinearem Drift gelöst. / In this thesis new robust integration techniques, which are suitable for various problems from stochastic analysis and mathematical finance, as well as some applications are presented. We begin with two different approaches to stochastic integration in robust financial mathematics. The first one is inspired by Ito’s integration and based on a certain topology induced by an outer measure corresponding to a minimal superhedging price. The second approach relies on the controlled rough path integral. We prove that this integral is the limit of non-anticipating Riemann sums and that every "typical price path" has an associated Ito rough path. For one-dimensional "typical price paths" it is further shown that they possess Hölder continuous local times. Additionally, we provide various generalizations of Föllmer’s pathwise Ito formula. Recalling that rough path theory can be developed using the concept of controlled paths and with a topology including the information of Levy’s area, sufficient conditions for the pathwise existence of Levy’s area are provided in terms of being controlled. This leads us to study Föllmer’s pathwise Ito formulas from the perspective of controlled paths. A multi-parameter extension to rough path theory is the paracontrolled distribution approach, recently introduced by Gubinelli, Imkeller and Perkowski. We generalize their approach from Hölder spaces to Besov spaces to solve rough differential equations. As an application we deal with stochastic differential equations driven by random functions. Finally, considering strongly coupled systems of forward and backward stochastic differential equations (FBSDEs), we extend the existence, uniqueness and regularity theory of so-called decoupling fields to Markovian FBSDEs with locally Lipschitz continuous coefficients. These results allow to solve the Skorokhod embedding problem for a class of Gaussian processes with non-linear drift.

INTRODUÇÃO: A punção aspirativa por agulha fina guiada por ecoendoscopia (PAAF-EE) é método consagrado para o diagnóstico de lesões sólidas de pâncreas. A aplicação de pressão negativa (PN) durante a PAAF-EE tem objetivo de manter o tecido junto à ponta cortante da agulha durante sua passagem através da lesão, resultando no desprendimento e retenção de células. A capilaridade (CP) é outra técnica que utiliza a retirada gradual do estilete durante a PAAF-EE e parece ser igualmente eficaz, além de evitar aspiração indesejada de hemácias e coágulos. OBJETIVO: Analisar o rendimento da ecopunção de lesões sólidas pancreáticas utilizando PN versus (vs) CP e os aspectos citológicos qualitativos e semiquantitativos da celularidade e contaminação por sangue dos grupos estudados. MÉTODO: No estudo, foram randomizados 50 pacientes com lesões sólidas de pâncreas para realização de PAAF-EE. Cada paciente foi submetido a quatro punções, intercalando as duas técnicas. A ordem das punções foi randomizada por computador. O grupo A (PN, CP, PN, CP) e o grupo B (CP, PN, CP, PN). RESULTADOS: As sensibilidade, especificidade e acurácia da PN vs CP foram 95,2% vs 92,3%; 100% vs 100%; 95,7% vs 93%, respectivamente. Quando foi considerada a associação das duas técnicas (PN+CP), os resultados da sensibilidade, especificidade e acurácia foram 95,6%, 100% e 96%. O valor preditivo positivo (VPP) foi alto para todas técnicas (100%) e os valores preditivos negativos (VPN) para PN, CP e associação dos métodos foram de 66,7% vs 57,1% vs 66,7%, respectivamente. Não houve diferença estatística no rendimento diagnóstico entre a PN e CP: 88% vs 80% (p=0,344), entretanto as técnicas somadas (PN+CP) foi superior à CP isolada: 94% vs 80% (p=0,016). A avaliação citológica qualitativa e semi-quantitativa de celularidade e contaminação por sangue no esfregaço e emblocado pelas técnicas de PN e CP não apresentou diferença estatística (p>0,05). CONCLUSÃO: O rendimento diagnóstico da PAAF-EE pela técnica de PN versus CP de massas sólidas de pâncreas não apresenta diferença estatística, entretanto a utilização das técnicas combinadas é superior, particularmente em relação à CP isolada. A celularidade e contaminação por sangue é semelhante independente da técnica utilizada (PN ou CP) ou do tipo de preparação citológica (esfregaço ou emblocado) / BACKGROUND: Endoscopic ultrasound fine needle aspiration (EUS-FNA) is an established diagnostic method for solid pancreatic masses. Application of negative pressure (NP) during EUS-FNA has the purpose of holding tissue against the cutting edge of the needle as it is moved through the lesion leading to cell detachment and drawing them up. Capillary (CP) sampling is another technique that removes the needle stylet gradually and continuously during the EUS-FNA and seems to have comparable results with less blood and clot aspiration. AIM: Analyze diagnostic yield of EUS-FNA of pancreatic solid mass using NP versus CP and evaluate cytological qualitative and semi-quantitative features of cellularity and blood contamination of each group. METHOD: A total of 50 patients were randomized for NP or CP EUSFNA with a standard 22G needle. Each patient had four passes using NP and CP in an alternate fashion. Computer randomization generated two groups. Group A (NP, CP, NP, CP) and group B (CP, NP, CP, NP). RESULTS: Diagnostic yield of NP versus CP had no statistical difference (p=0.344). Both techniques (NP+CP) was superior to CP alone (p=0.016), but not to NP alone (p=0.25). Sensitivity, specificity and accuracy of NP vs CP were 95.2% vs 92.3%; 100% vs 100%; 95.7% vs 93%, respectively. Results for sensitivity, specificity and accuracy of both NP+CP were 95.6%, 100% and 96%. Positive predictive value was high for all techniques (100%) and Negative predictive value for NP, CP and both techniques were 66.7%, 57.1% and 66.7%, respectively. NP and CP smears and cell blocks had no statistical differences in qualitative and semi-quantitative citological evaluation for cellularity and bloodiness (p > 0.05). CONCLUSIONS: NP versus CP in EUS-FNA of solid pancreatic mass yielded similar overall outcomes in terms of diagnostic performance, however the combination of both techniques is superior, particularly compared to CP alone. Cellularity and bloodiness are equivalent no matter which technique (NP or CP) or type of cytological preparation (smear or cell block) is used

A family of Natural Language Processing (NLP) tasks such as part-of- speech (PoS) tagging, Named Entity Recognition (NER), and Multiword Expression (MWE) identification all involve assigning labels to sequences of words in text (sequence labeling). Most modern machine learning approaches to sequence labeling utilize word embeddings, learned representations of text, in which words with similar meanings have similar representations. Quite recently, contextualized word embeddings have garnered much attention because, unlike pretrained context- insensitive embeddings such as word2vec, they are able to capture word meaning in context. In this thesis, I evaluate the performance of different embedding setups (context-sensitive, context-insensitive word, as well as task-specific word, character, lemma, and PoS) on the three abovementioned sequence labeling tasks using a deep learning model (BiLSTM) and Portuguese datasets. v

Cloud Infrastructure-as-a-Service (IaaS) is a form of utility computing which has emerged with the recent innovations in the service computing and data communication technologies. Regardless of the fact that IaaS is attractive for application service providers, satisfying user requests while ensuring cloud operational objectives is a complicated task that raises several resource management challenges. Among these challenges, limited controllability over network services delivered to cloud consumers is prominent in single datacenter cloud environments. In addition, the lack of seamless service migration and optimization, poor infrastructure utilization, and unavailability of efficient fault tolerant techniques are noteworthy challenges in geographically distributed datacenter clouds. Initially in this thesis, a datacenter resource management framework is presented to address the challenge of limited controllability over cloud network traffic. The proposed framework integrates network virtualization functionalities offered by software defined networking (SDN) into cloud ecosystem. To provide rich traffic control features to IaaS consumers, control plane virtualization capabilities offered by SDN have been employed. Secondly, a quality of service (QoS) aware seamless service migration and optimization framework has been proposed in the context of geo-distributed datacenters. Focus has been given to a mobile end-user scenario where frequent cloud service migrations are required to mitigate QoS violations. Finally, an SDN-based dynamic fault restoration scheme and a shared backup-based fault protection scheme have been proposed. The fault restoration has been achieved by introducing QoS-aware reactive and shared risk link group-aware proactive path computation algorithms. Shared backup protection has been achieved by optimizing virtual and backup link embedding through a novel integer linear programming approach. The proposed solutions significantly improve bandwidth utilization in inter-datacenter networks while recovering from substrate link failures.

We investigate various relationships between categories of functors. The major examples are given by extending some duality to a larger structure, such as an adjunction or a recollement of abelian categories. We prove a theorem which provides a method of constructing recollements which uses 0-th derived functors. We will show that the hypotheses of this theorem are very commonly satisfied by giving many examples. In our most important example we show that the well-known Auslander-Gruson-Jensen equivalence extends to a recollement. We show that two recollements, both arising from different characterisations of purity, are strongly related to each other via a commutative diagram. This provides a structural explanation for the equivalence between two functorial characterisations of purity for modules. We show that the Auslander-Reiten formulas are a consequence of this commutative diagram. We define and characterise the contravariant functors which arise from a pp-pair. When working over an artin algebra, this provides a contravariant analogue of the well-known relationship between pp-pairs and covariant functors. We show that some of these results can be generalised to studying contravariant functors on locally finitely presented categories whose category of finitely presented objects is a dualising variety.

Durant cette thèse, nous avons introduit les problèmes de Bin Covering avec Contrainte de Distance (BCCD) et de Bin Packing avec Contrainte de Distance (BPCD), qui trouvent leur application dans les réseaux de grande échelle, tel Internet. L'étude de ces problèmes que nous effectuons dans des espaces métriques quelconques montre qu'il est impossible de travailler dans un tel cadre sans avoir recours à de l'augmentation de ressources, un procédé qui permet d'élaborer des algorithmes construisant des solutions moins contraintes que la solution optimale à laquelle elles sont comparées. En plus de résultats d'approximation intéressants, nous prouvons la difficulté de ces problèmes si ce procédé n'est pas utilisé. Par ailleurs, de nombreux outils ont pour objectif de plonger les grands réseaux qui nous intéressent dans des espaces métriques bien décrits. Nous avons alors étudié nos problèmes dans plusieurs espaces métriques spécifiques, et, en particulier, ceux générés par certains de ces outils, comme Vivaldi et Sequoia. / During this Ph.D we introduced Bin Covering under Distance Constraint (BCCD in French) and Bin Packing under Distance Constraint (BPCD in French). Those two problems find their applications in the context of large scale networks, like Internet. We studied those problems in general metric spaces, and proved that using resource augmentation is mandatory. Resource augmentation allows to build algorithms working on solutions with less constraints than the optimal solution to which it is compared to. We found interesting approximations algorithms using this relaxation, and proved the necessity of this resource augmentation. However many tools are used to embed large networks we are interested in in specific metric spaces. Thus we studied those problems in different specific metric spaces, in particular those generated by the use of Vivaldi and Sequoia, two of those tools.

Cette thèse présente de nouvelles méthodes de synthèse de texture basées sur l'exemple pour les problèmes de prédiction d'images (c'est à dire, codage prédictif) et d'inpainting d'images. Les principales contributions de cette étude peuvent aussi être vues comme des extensions du template matching. Cependant, le problème de synthèse de texture tel que nous le définissons ici se situe plutôt dans un contexte d'optimisation formalisée sous différentes contraintes. Le problème de prédiction d'images est d'abord situé dans un contexte de représentations parcimonieuses par l'approximation du template sous contraintes de parcimonie. La méthode de prédiction proposée avec les dictionnaires adaptés localement montrent de meilleures performances par rapport aux dictionnaires classiques (tels que la transformée en cosinus discrète (TCD)), et à la méthode du template matching. Le problème de prédiction d'images est ensuite placé dans un cadre d'apprentissage de dictionnaires en adaptant les méthodes traditionnelles d'apprentissage pour la prédiction de l'image. Les observations expérimentales montrent une meilleure performance comparativement à des méthodes de prédiction parcimonieuse et des prédictions intra de type H.264/AVC. Enfin un cadre neighbor embedding est proposé pour la prédiction de l'image en utilisant deux méthodes de réduction de dimensionnalité: la factorisation de matrice non négative (FMN) et le locally linear embedding (LLE). Ce cadre est ensuite étendu au problème d'inpainting d'images. Les évaluations expérimentales démontrent l'efficacité des idées sous-jacentes pour la compression via la prédiction d'images et l'inpainting d'images.

<p>The main result in this thesis is the generalisation of Bergman's diamond lemma for ring theory to power series rings. This generalisation makes it possible to treat problems in which there arise infinite descending chains. Several results in the literature are shown to be special cases of this diamond lemma and examples are given of interesting problems which could not previously be treated. One of these examples provides a general construction of a normed skew field in which a custom commutation relation holds.</p><p>There is also a general result on the structure of totally ordered semigroups, demonstrating that all semigroups with an archimedean element has a (up to a scaling factor) unique order-preserving homomorphism to the real numbers. This helps analyse the concept of filtered structure. It is shown that whereas filtered structures can be used to induce pretty much any zero-dimensional linear topology, a real-valued norm suffices for the definition of those topologies that have a reasonable relation to the multiplication operation.</p><p>The thesis also contains elementary results on degree (as of polynomials) functions, norms on algebras (in particular ultranorms), (Birkhoff) orthogonality in modules, and construction of semigroup partial orders from ditto quasiorders.</p>

The main result in this thesis is the generalisation of Bergman's diamond lemma for ring theory to power series rings. This generalisation makes it possible to treat problems in which there arise infinite descending chains. Several results in the literature are shown to be special cases of this diamond lemma and examples are given of interesting problems which could not previously be treated. One of these examples provides a general construction of a normed skew field in which a custom commutation relation holds. There is also a general result on the structure of totally ordered semigroups, demonstrating that all semigroups with an archimedean element has a (up to a scaling factor) unique order-preserving homomorphism to the real numbers. This helps analyse the concept of filtered structure. It is shown that whereas filtered structures can be used to induce pretty much any zero-dimensional linear topology, a real-valued norm suffices for the definition of those topologies that have a reasonable relation to the multiplication operation. The thesis also contains elementary results on degree (as of polynomials) functions, norms on algebras (in particular ultranorms), (Birkhoff) orthogonality in modules, and construction of semigroup partial orders from ditto quasiorders.