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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Villes ouvertes. La flânerie dans les images urbaines de Chris Marker / Opend cities. flânerie in Chris Marker's city images

Azuma, Shiho 06 December 2014 (has links)
Chris Marker, (1921-2012) qui photographie et filme des lieux divers dans le monde entier, avait pour thème de prédilection la ville. En effet, ce lieu de circulation et de mobilité, dépassant toutes les clôtures, se prête particulièrement aux œuvres markériennes, caractérisées par l’entrecroisement de différents espace-temps, et par l’expérience de l’altérité. En étant à la fois cinéaste et voyageur, les images de la ville capturées par Marker se caractérisent par le déplacement, en particulier par l’expérience de la flânerie, qui constitue un élément essentiel de la réflexion philosophique sur la ville moderne de Walter Benjamin (1892-1940). Pour cette raison, cette thèse est consacrée à l’analyse des œuvres de Marker autour du thème de la flânerie. Ainsi, au cours de trois parties, nous travaillerons des concepts reliées à la flânerie : le seuil, l’allégorie, et le chiffonnier. Ces travaux thématiques nous aideront à comprendre la stratification complexe de l’espace-temps, le caractère transitoire, et l’art de l’assemblage dans les images markériennes. Ces recherches sont finalement élargies à la notion de la navigation comme version renouvelée de flânerie, pour analyser l’espace de L’Ouvroir, le monde virtuel crée sur Second Life par Marker dans sa dernière période. Par conséquence, à la lumière des problématiques abordées par la flânerie, on comprend que la création artistique de Marker est fondée sur la quête continuelle de nouvelles expérience visuelles qui remettent en question la modernité et la représentation cinématographique. / Chris Marker (1921-2012) is a filmmaker, who took photos and filmed various places by travelling all over the world. The city had been one of the important subjects for Marker’s works. Suppose every metropolis is essentially a limitless place, filled with flow and mobility, Marker’s works, described as intersection of different time and space and “otherness,” can be said that they inherit the nature of metropolis. Being filmmaker and traveler, Marker’s images of city are often characterized by “moving”, particularly by the experience of flânerie (stroll), which constitutes element of philosophical reflection of modern city by Walter Benjamin (1892-1940). In order to make this point clear, this dissertation deals with the films of Marker using Benjamin’s concept flânerie, as a major analyzing concept. Using four key concepts, threshold, allegory, and rag-and-bone man related to the experience of flânerie, this dissertation dissects the complex stratification of “space-time”, the “ephemeral character”, and the “art of collecting” in the images of Marker. Also, bringing the new concept “navigation”, as a renewed version of flânerie, the space of L’Ouvroir, the territorialities of Second Life, created in Marker’s last years of his life is analyzed. As a result, in the light of the issues raised by flânerie, we understand that Chris Marker problematizes the modernity and the system of cinematic representation based on the continual search for new visual experience.
32

The Mechanism Of Fragility Of The BCL2 And HOX11 Breakpoint Regions During t(14;18) And t(10;14) Chromosomal Translocations In Lymphoid Cancers

Nambiar, Mridula 05 1900 (has links) (PDF)
Haematological cancers like leukemia and lymphoma are characterized by genetic abnormalities, specifically chromosomal translocations. Analyses of the translocation breakpoint regions in patients have shown that some loci in the genome are more susceptible to breakage than others. However, very little is known about the mechanism of generation of many such chromosomal translocations. In the present study, we have attempted to understand the mechanism of fragility of three regions, which are prone to breaks during translocations in follicular lymphoma (FL) and T-cell leukemia. The t(14;18) translocation in FL is one of the most common chromosomal translocations. Most breaks on chromosome 18 are located at the 3’ UTR of the BCL2 gene and are broadly classified into three clusters, namely major breakpoint region (mbr), minor breakpoint cluster region (mcr) and the intermediate cluster region (icr). The RAG complex has been shown to cleave BCL2 mbr by recognizing an altered DNA structure. In the present study, by using a gel based assay, nature of the non-B DNA structure at BCL2 mbr was identified as parallel intramolecular G-quadruplex. Various studies including circular dichroism (CD), mutagenesis, DMS modification assay and 1H NMR showed the presence of three guanine tetrads in the structure. Further, evidence was also found for the formation of such a G-quadruplex structure within mammalian cells. In an effort to characterize the mechanism of fragility of mcr, a unique pattern of RAG cleavage was observed in a sequence dependent manner. Three independent nicks of equal efficiency were generated by RAGs at the cryptic sequence, “CCACCTCT”, at mcr and at a cytosine upstream of it, unlike a single specific nick at the 5’ of heptamer during V(D)J rearrangement. Interestingly, RAG nicking at mcr occured in the presence of both Mg2+ and Mn2+. Using recombination assay, followed by sequencing of the junctions, we find that mcr can recombine with standard RSS in vivo, albeit at a very low frequency. Mutations to this novel motif abolish recombination at the mcr within the cells. In order to determine the prevalence of t(14;18) translocation in the healthy Indian population, nested PCR approach followed by Southern hybridization was used. Results showed 34% prevalence of t(14;18) translocation in the Indian population. Although, no gender based difference was observed, an age dependent increase was found in adults. Further, presence of the t(14;18) transcripts was also detected. The mechanism underlying the fragility of the t(10;14) translocation involving HOX11 gene in T-cell leukemia is not known. Using primer extension assays on a plasmid DNA containing HOX11 breakpoint region, presence of consistent pause sites corresponding to two G-quadruplex forming regions, flanking the patient breakpoints, were detected. These replication blocks were dependent on K+ ions. Native gel shift assays, mutation analysis, S1 nuclease and CD, further revealed formation of intermolecular G-quadruplexes, unlike the BCL2 mbr. Further, sodium bisulfite modification assay indicated the presence of such structures in the genomic DNA within cells. Hence, we propose that two independent G-quadruplex structures formed in the HOX11 gene could interact with each other, thereby resulting in fragility of the intervening sequences, where majority of the patient breakpoints are mapped. Overall, this study has attempted to understand the role of both sequence and structure of DNA, in generating chromosomal fragility during t(14;18) translocation in FL and t(10;14) translocation in T-cell leukemia. These results may facilitate future studies in unraveling the mechanism leading to genomic instability in other lymphoid cancers.
33

Återbrukets estetik - Uppländska trasryor : Förekomst, tillverkning, funktion och värde

Hakanen, Eva January 2020 (has links)
Since the beginning of the early 20th century bed rugs have been interesting research objects, but only in passing researchers have paid attention to rugs woven with rags. Noone has taken a closer look upon the reasons why people have woven these rugs. What does the materials of the rag – like recycled garments and interior textiles in the form of clothing rags – have to tell about the times when these rugs were woven? Did the rag rugs have any specific function or were the materials available and therefore used? The main sources of information are 21 rag rugs from Roslagen in Uppland, with a varied amount of rags. They were woven during the latter half of 19th century, and estate inventories from Väddö- and Häverö Ship District have altogether given some answers to the primary question of this paper: in wich way can the examined bed rugs bear witness to the use and value of recycled textile materials and the view of these in the context of the community where they were manufactured and used? This research doesn´t give an answer to whether these rugs have any particular function or not. Instead these rag rugs can be looked upon as representing a general development of the society towards an increasing amount of textiles surplus material. This being due an increasing consumption of factory-made clothing and textiles, manufactured in factories, as well as the paper mills development from producing paper made of cellulose rather than textile waste. To this we can add a principle lingering on from the 19th century, of domestic production and a thrift of resources. This resulted in an obvious recycling of discarded textiles. The home weaving of interior textiles was still strong by the end of the 19th century, and in Rosagen there was also a long tradition of weaving and of using rugs in the beds. At the same time there was, in the coastal regions of Roslagen, a local need for warming covers in boats and boat houses. This demand was related to the shooting of seals and other hunting in the coastal areas, as well as in the fishing- and maritime trades.
34

RAG-based data extraction : Mining information from second-life battery documents

Edström, Jesper January 2024 (has links)
With the constant evolution of Large Language Models (LLMs), methods for minimizing hallucinations are being developed to provide more truthful answers. By using Retrieval-Augmented Generation (RAG), external data can be provided to the model on which its answers should be based. This project aims at using RAG for a data extraction pipeline specified for second-life batteries. By pre-defining the prompts the user may only provide the documents that are wished to be analyzed, this is to ensure that the answers are in the correct format for further data processing. To process different document types, initial labeling takes place before more specific extraction suitable for the document can be applied. Best performance is achieved by grouping questions that allow the model to reason around what the relevant questions are so that no hallucinations occur. Regardless of whether there are two or three document types, the model performs equally well, and it is clear that a pipeline of this type is well suited to today's models. Further improvements can be achieved by utilizing models containing a larger context window and initially using Optical Character Recognition (OCR) to read text from the documents.
35

Review of subnational credit rating methodologies and their applicability in South Africa / Erika Fourie

Fourie, Erika January 2015 (has links)
The objectives of the research study are to review existing subnational credit rating methodologies and their applicability in the South African context, to develop the quantitative parts of credit rating methodologies for two provincial departments (Department of Health and Department of Education) that best predict future payment behaviour, to test the appropriateness of the proposed methodologies and to construct the datasets needed. The literature study includes background information regarding the uniqueness of South Africa’s provinces and credit rating methodologies in general. This is followed by information on subnational credit rating methodologies, including a review of existing subnational credit rating methodologies and an assessment of the applicability of the information provided in the South African context. Lastly, the applicable laws and regulations within the South African regulatory framework are provided. The knowledge gained from the literature study is applied to the data that have been collected to predict the two departments’ future payment behaviour. Linear regression modelling is used to identify the factors that best predict future payment behaviour and to assign weights to the identified factors in a scientific manner. The resulting payment behaviour models can be viewed as the quantitative part of the credit ratings. This is followed by a discussion on further investigations to improve the models. The developed models (both the simple and the advanced models) are tested with regard to prediction accuracies using RAG (Red, Amber or Green) statuses. This is followed by recommendations regarding future model usage that conclude that the department-specific models outperform the generic models in terms of prediction accuracies. / PhD (Risk analysis), North-West University, Potchefstroom Campus, 2015
36

Review of subnational credit rating methodologies and their applicability in South Africa / Erika Fourie

Fourie, Erika January 2015 (has links)
The objectives of the research study are to review existing subnational credit rating methodologies and their applicability in the South African context, to develop the quantitative parts of credit rating methodologies for two provincial departments (Department of Health and Department of Education) that best predict future payment behaviour, to test the appropriateness of the proposed methodologies and to construct the datasets needed. The literature study includes background information regarding the uniqueness of South Africa’s provinces and credit rating methodologies in general. This is followed by information on subnational credit rating methodologies, including a review of existing subnational credit rating methodologies and an assessment of the applicability of the information provided in the South African context. Lastly, the applicable laws and regulations within the South African regulatory framework are provided. The knowledge gained from the literature study is applied to the data that have been collected to predict the two departments’ future payment behaviour. Linear regression modelling is used to identify the factors that best predict future payment behaviour and to assign weights to the identified factors in a scientific manner. The resulting payment behaviour models can be viewed as the quantitative part of the credit ratings. This is followed by a discussion on further investigations to improve the models. The developed models (both the simple and the advanced models) are tested with regard to prediction accuracies using RAG (Red, Amber or Green) statuses. This is followed by recommendations regarding future model usage that conclude that the department-specific models outperform the generic models in terms of prediction accuracies. / PhD (Risk analysis), North-West University, Potchefstroom Campus, 2015
37

Automated Generation of Round-robin Arbitration and Crossbar Switch Logic

Shin, Eung Seo 25 November 2003 (has links)
The objective of this thesis is to automate the design of round-robin arbiter logic. The resulting arbitration logic is more than 1.8X times faster than the fastest prior state-of-the-art arbitration logic the author could find reported in the literature. The generated arbiter implemented in a single chip is fast enough in 0.25ьm CMOS technology to achieve terabit switching with a single chip computer network switch. Moreover, this arbiter is applicable to crossbar (Xbar) arbitration logic. The generated Xbar, customized according to user specifications, provides multiple communication paths among masters and slaves. As the number of transistors on a single chip increases rapidly, there is a productivity gap between the number of transistors available in a chip and the number of transistors per hour a chip designer designs. One solution to reduce this productivity gap is to increase the use of Silicon Intellectual Property (SIP) cores. However, a SIP core should be customized before being used in a system different than the one for which it was designed. Thus, to reconfigure the SIP core, either an engineer must spend significant effort altering the core by hand or else an enhanced CAD tool can automatically customize the core according to customer specifications. In this thesis, we present SIP generator tools for arbiter and Xbar generation. First, we introduce a Round-robin Arbiter Generator (RAG). The RAG can generate a hierarchical Bus Arbiter (BA) which is faster than all known previous approaches. RAG can also generate a hierarchical Switch Arbiter (SA) which is faster than all known previous approaches. Using a 0.25ьm TSMC standard cell library from LEDA Systems, we show the arbitration time of a 32x32 SA and demonstrate that our SA meets the time constraint to achieve terabit throughput. Furthermore, using a novel token-passing hierarchical arbitration scheme, our 32x32 SA performs better than the Ping-Pong Arbiter and Programmable Priority Encoder by factors of 1.8X and 2.3X, respectively, with less power dissipation. Finally, we present an Xbar switch Generator (X-Gt) tool that automatically configures a crossbar for a multiprocessor System-on-a-Chip (SoC). An Xbar is generated in Register Transfer Level (RTL) Verilog HDL.
38

Modélisation des réactions de gonflement interne des bétons avec prise en compte des couplages poro-mécaniques et chimiques / Modelling of concrete internal swelling reactions with poro-chemo-mechanical complings

Morenon, Pierre 14 November 2017 (has links)
Les réactions de gonflements internes (RGI) sont des pathologies qui dégradent le béton de certains ouvrages tels que des barrages en étant à l'origine de gonflements. Electricité De France (EDF) doit assurer la sûreté des personnes et des biens situés à l'aval de ses structures. Ce travail a pour but d'améliorer la modélisation des phénomènes physiques liés à ces dégradations notamment l'interaction entre le produit gonflant et le squelette solide. La contrainte intraporeuse générée par la pression du produit peut créer un endommagement. Dans le modèle proposé, la fissuration peut avoir lieu à deux échelles : - Au niveau microscopique c'est le produit gonflant qui comble le volume libre autour du site de réaction avant de mettre en traction le matériau jusqu'à fissuration, ce qui provoque une baisse des caractéristiques du matériau (résistances en traction et en compression, module d'Young). Un critère de plasticité anisotrope et une loi d'écrouissage positif sont proposés pour modéliser ce phénomène. - Au niveau macroscopique, des gradients de gonflements peuvent se développer à l'intérieur d'ouvrages dont les états de contraintes et les conditions d'humidité et de température ne sont pas homogènes. Une fissuration localisée peut alors s'initier. Elle est la source de risques de dislocations des structures pouvant mener à leur ruine, de concentrations de contraintes dans les aciers structuraux, de chemins facilités pour les agents agressifs extérieurs et pour l'eau, composé essentiel au développement rapide de ces pathologies. La prise en compte des couplages hydro-poro-mécaniques est nécessaire à la simulation de ces phénomènes. Cette fissuration est modélisée par un critère plastique de Rankine anisotrope dont l'énergie dissipée par la fissuration est régularisée par la méthode d'Hillerborg. Après avoir présenté ce modèle, il est validé et appliqué à différentes échelles pour des états de contraintes et des conditions environnementales diverses, sur : - des éprouvettes soumises à des contraintes et des blocages multi-axiaux, - des poutres de laboratoire plus ou moins armées subissant des gradients d'humidité importants, - des barrages dans des conditions réelles construits dans les années 1950. Les résultats obtenus avec le modèle permettent de retrouver les déplacements, les contraintes et les résistances de ces structures après vieillissement. Pour les poutres atteintes de réaction alcali-silice, les résultats numériques obtenus montrent notamment une prise en compte réaliste des contraintes induites par la présence d'armatures, ce qui est confirmé par la validation du comportement à rupture. Néanmoins, des difficultés de calage subsistent pour les poutres subissant la réaction sulfatique interne. Elles sont issues des grandes amplitudes d'expansion et des couplages diffusion-fissuration qui rendent spécifique le comportement de ces structures par rapport à des structures subissant des expansions moins importantes. Ce modèle est un outil pour la requalification des ouvrages dans le but d'assurer leur sûreté. Il peut également servir de base de calcul à la simulation de diverses réhabilitations et travaux de confortements. / Internal swelling reactions (ISR) damage the concrete of structures such as dams. Electricité De France (EDF) must ensure the safety of the people and goods located below the dam. This work aims to improve the modeling of the physical phenomena related to these damages, especially the interaction between the swelling product and the solid skeleton. The intraporous stress generated by the product pressure can create cracking, which, in the proposed model, can occur at two scales: - At a microscopic scale, the swelling product fills the gaps around the reaction site, which induces cracking and a decrease of the materials' characteristics (tensile and compression strengths, Young's modulus). Numerically, an anisotropic plastic criteria and a hardening law allow modelling this phenomenon. - At a macroscopic level, swelling gradients can develop inside concrete structures whose stress states and climatic conditions (humidity and temperature) are not homogeneous. A localized cracking can begin. It is a source of structure dislocation risks and stress concentrations in structural reinforcement. It may ease the way in for outside aggressive agents and water, an essential component for these reactions. Hydro-poro-mechanical couplings need to be taken into account when simulating these phenomena. The cracking is modelled by a Rankine plastic criterion whose dissipated energy is regularized by the Hillerborg's method. After presenting the model, several stress states and environmental conditions are applied to the model in order to validate it on: - samples under multi-axial stresses and restraints, - plain and reinforced beams submitted to moisture gradients in laboratory, - 1950s dams in real conditions. The results of the model make it possible to reproduce the displacements, the stresses and residual strength of these structures after aging. For the beams submitted to alkali aggregate reaction, the numerical results show a relevant prediction of the stress induced by reinforcement, confirmed by the failure behaviour. Nevertheless, the model encounters calibration difficulties for beams affected by delayed ettringite formation. They come from large swelling amplitude and diffusion-cracking coupling which are inherent to these structure behaviours. This model is a tool for concrete structure requalification in order to ensure their safety. It can also be a basis for diverse rehabilitations and reinforcement works simulation.
39

Towards Attribute Grammars for Metamodel Semantics

Bürger, Christoff, Karol, Sven 15 August 2011 (has links)
Of key importance for metamodelling are appropriate modelling formalisms. Most metamodelling languages permit the development of metamodels that specify tree-structured models enriched with semantics like constraints, references and operations, which extend the models to graphs. However, often the semantics of these semantic constructs is not part of the metamodel, i.e., it is unspeci ed. Therefore, we propose to reuse well-known compiler construction techniques to specify metamodel semantics. To be more precise, we present the application of reference attribute grammars (RAGs) for metamodel semantics and analyse commonalities and differences. Our focus is to pave the way for such a combination, by exemplifying why and how the metamodelling and attribute grammar (AG) world can be combined and by investigating a concrete example - the combination of the Eclipse Modelling Framework (EMF) and JastAdd, an AG evaluator generator.
40

L’IL-7 et les cellules dendritiques dans le développement et l’homéostasie des lymphocytes T

Mohamed Moutuou, Moutuaata 08 1900 (has links)
Les cellules dendritiques (CD) et l'interleukine-7 (IL-7) sont deux facteurs essentiels au développement et à l'homéostasie des lymphocytes T. Une anomalie de la production ou de la signalisation de l’IL-7 est associée à un défaut de la thymopoïèse en plus d’une profonde lymphopénie. Parallèlement, la déficience des CD, entraine une rupture de la tolérance au soi menant au développement de maladies auto-immunes et une altération de l’homéostasie des Lymphocyte T. Dans le cadre de cette thèse, nous nous sommes intéressés globalement à la contribution de l’IL-7 et des CD dans la reconstitution et l'homéostasie des lymphocytes dans deux contextes thérapeutiques différents. Premièrement, il a été démontré que le traitement avec l'imatinib (médicament utilisé pour traiter la leucémie myéloïde chronique (LMC)) induisait une diminution du nombre de lymphocytes T chez les patients atteints de LMC. À partir de notre étude in vitro sur des cellules mononuclées du sang périphérique (peripheral blood mononuclear cells) (PBMC) humaines cultivées en présence d’imatinib avant d’être stimuler par l’IL-7 à différentes concentrations, nous avons mis en évidence une perturbation de la signalisation de l’IL-7 dans les lymphocytes T suite à une interférence avec l’imatinib. À l’aide de notre modèle murin traité à l’imatinib, nous avons également montré in vivo, une altération de l’homéostasie des lymphocyte T. La modulation négative de l’homéostasie des LT par l’imatinib est également accompagnée d’une diminution dramatique de la proportion des CD, ce qui pourrait également faire décliner le pool des lymphocyte T. Deuxièmement, dans un contexte de greffe de moelle osseuse (MO) syngénique, nous avons analysé la contribution de l’IL-7 produite par les CD, dans la thymopoïèse et l’homéostasie des lymphocyte T. Pour évaluer la contribution de l’IL-7 produite par les cellules hématopoïétiques dans la reconstitution et l’homéostasie lymphocytaire T, nous avons généré des chimères de MO avec une production d’IL-7 exclusivement limitée aux cellules stromales, par greffe de MO IL-7-/- dans des souris Rag -/-. Les souris Rag -/- transplantées avec des cellules de MO IL-7 - /- développent une maladie auto-immune systémique létale à 4-5 semaines post greffe. Nos résultats suggèrent fortement une contribution cruciale de l’IL-7 produite par les CSH (Cellules Souches Hématopoïétiques) dans la reconstitution immunitaire après greffe de MO. L’ensemble de nos travaux contribue à élargir la compréhension de la biologie de l'axe IL-7/ IL-7Rα et des CD dans le développement et l’homéostasie des lymphocytes T. / Dendritic cells (DCs) and interleukin-7 (IL-7) are two factors essential for the development and homeostasis of T lymphocytes. An abnormality in the production or signaling of IL-7 is associated with a defective thymopoiesis and severe lymphopenia. DCs deficiency leads to a breakdown in self-tolerance leading to the development of autoimmune diseases and impaired T cells homeostasis. In this thesis, we have focused on the contribution of IL-7 and DCs in the reconstitution and homeostasis of lymphocytes in two different therapeutic contexts. Firstly, imatinib (drug used to treat chronic myeloid leukemia (CML)) has been shown to induce a decrease of T lymphocytes number in patients with CML. From our in vitro study on human peripheral blood mononuclear cells (PBMCs) cultured in the presence of imatinib before stimulation by IL-7 at different concentrations, we demonstrated a disruption of IL-7 signaling in T cells following interference with imatinib. Using our imatinib-treated mouse model, we also showed in vivo impaired T cells homeostasis. The negative modulation of T lymphocytes homeostasis by imatinib is also accompanied by a dramatic decrease in the proportion of DCs, which could also decline T cells pool. Secondly, we used murine syngeneic bone marrow transplantation (BMT) models to study the contribution of IL-7 produced by DCs in thymopoiesis and T cells homeostasis. To assess the role of IL-7 produced by DCs in T cell reconstitution and homeostasis, we generated BM chimeras with IL-7 production exclusively limited to stromal cells, by BMT of IL-7 - / - into Rag - / - mice. Rag - / - mice transplanted with IL-7 -/- BM cells develop a lethal systemic autoimmune disease post-transplant at 4-5 weeks post-BMT. Our results strongly suggest a major contribution of Hematopoietic stem cells (HSC)-produced IL-7 in immune reconstitution after BM transplantation. Our work contributes to expanding our understanding of the biology of the IL-7 / IL-7Rα axis and DCs in T cell development and homeostasis.

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