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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.
61

Learning Embeddings for Fashion Images

Hermansson, Simon January 2023 (has links)
Today the process of sorting second-hand clothes and textiles is mostly manual. In this master’s thesis, methods for automating this process as well as improving the manual sorting process have been investigated. The methods explored include the automatic prediction of price and intended usage for second-hand clothes, as well as different types of image retrieval to aid manual sorting. Two models were examined: CLIP, a multi-modal model, and MAE, a self-supervised model. Quantitatively, the results favored CLIP, which outperformed MAE in both image retrieval and prediction. However, MAE may still be useful for some applications in terms of image retrieval as it returns items that look similar, even if they do not necessarily have the same attributes. In contrast, CLIP is better at accurately retrieving garments with as many matching attributes as possible. For price prediction, the best model was CLIP. When fine-tuned on the dataset used, CLIP achieved an F1-Score of 38.08 using three different price categories in the dataset. For predicting the intended usage (either reusing the garment or exporting it to another country) the best model managed to achieve an F1-Score of 59.04.
62

Технико-экономическое сравнение способов усиления железобетонных колонн : магистерская диссертация / Technical and economic comparison of ways to strengthen reinforced concrete columns

Давыдов, М. Ю., Davydov, M. Yu. January 2022 (has links)
Проведено сравнение технико-экономических показателей известных методов усиления железобетонных колонн для различной категории технического состояния. / The comparison of technical and economic indicators of known methods of strengthening reinforced concrete columns for various categories of technical condition is carried out.
63

Interacción cardiovascular angiotensina II- péptido natriurético en la hipertensión arterial experimental

Ortiz Ruiz, Antonio José 31 July 1998 (has links)
Hemos inducido en ratas wistar dos modelos de hipertensión arterial (HTA): hipertensión vasculorrenal 2 riñones-1 clip (2R-1C) e hipertensión por déficits crónico de óxido nítrico (NO). La angiotensina II (AII) participa en el desarrollo y mantenimiento de la hipertensión vasculorrenal y por déficit crónico de NO. La administración crónica de losartán, aún previniendo el desarrollo de la hipertensión por déficit crónico de NO, no confiere protección completa frente a las alteraciones hemodinámicas que dicha hipertensión conlleva. Los bloqueantes de los receptores de la AII, saralasina y losartán, poseen efectos hemodinámicos similares, aunque de distinta potencia, sobre los grupos de HTA. En condiciones normales, los efectos hemodinámicos del péptido natriurético auricular (PNA) no son modulados por los receptores de AII. La HTA potencia los efectos hemodinámicos del PNA por un efecto en el que intervienen los receptores de AII. / We have induced in Wistar rats two models of experimental hypertension: two kidney-one clip hypertension (2K-1C) and hypertension induced by chronic inhibition of nitric oxide production (L-NAME-induced hypertension). In both, angiotensin II (AII) participates in the development and maintenance of the hypertension. Chronic administration of losartan prevents the development of the L-NAME-induced hypertension, although it does not confer complete protection to the hemodynamic alterations that this hypertension causes. The AII receptor antagonists, saralasin and losartan, have similar hemodynamic effects on the hypertensive groups, although in different degrees. Moreover, the hemodynamic effects of the atrial natriuretic peptide (ANP) under normal conditions are not modulated by the AII receptor. However, hypertension increases the hemodynamic effects of the ANP by an effect partially due to the AII receptors
64

Etude thermomécanique expérimentale et numérique d'un module d'électronique de puissance soumis à des cycles actifs de puissance / Thermo-mechanical study of a power module under active power cycling by means of experiments and simulations

Durand, Camille 23 January 2015 (has links)
De nos jours, la durée de vie des modules d’électronique de puissance est désormais limitée par les technologies standards de conditionnement, telles que le câblage par fils et le brasage. Ainsi une optimisation des technologies actuellement employées n’est pas suffisante pour satisfaire les futures exigences de fiabilité. Pour dépasser ces limites, un nouveau module de puissance remplaçant les fils de connexion par des clips en cuivre a été développé. Ce design innovant vise à améliorer la fiabilité du module puisqu’il empêche la dégradation des fils de connexion, constituant bien souvent la principale source de défaillance. La contrepartie de ce gain de fiabilité réside dans la complexification de la structure interne du module. En effet, l’emploi d’un clip en cuivre nécessite une brasure supplémentaire fixant le clip à la puce. Ainsi, le comportement thermomécanique et les différents modes de rupture auxquels le composant est soumis lors de son utilisation doivent être caractérisés. Cette étude utilise la simulation numérique pour analyser avec précision le comportement de chaque couche de matériaux lors des cycles actifs de puissance. De plus, une étude de sensibilité à la fois expérimentale et numérique concernant les paramètres de tests est réalisée. Les zones critiques du module ainsi que les combinaisons critiques des paramètres de tests pour les différents modes de rupture sont mis en évidence. Par ailleurs, une analyse en mécanique de la rupture est conduite et la propagation des fissures à différentes zones clés est analysée en fonction des différents paramètres de tests. Les résultats obtenus permettent la définition de modèles de prédiction de durée de vie. / Today a point has been reached where safe operation areas and lifetimes of power modules are limited by the standard packaging technologies, such as wire bonding and soft soldering. As a result, further optimization of used technologies will no longer be sufficient to meet future reliability requirements. To surpass these limits, a new power module was designed using Cu clips as interconnects instead of Al wire bonds. This new design should improve the reliability of the module as it avoids wire bond fatigue failures, often the root cause of device failures. The counterpart for an improved reliability is a quite complicated internal structure. Indeed, the use of a Cu clip implies an additional solder layer in order to fix the clip to the die. The thermo-mechanical behavior and failure mechanisms of such a package under application have to be characterized. The present study takes advantage of numerical simulations to precisely analyze the behavior of each material layer under power cycling. Furthermore an experimental and numerical sensitivity study on tests parameters is conducted. Critical regions of the module are pointed out and critical combinations of tests parameters for different failure mechanisms are highlighted. Then a fracture mechanics analysis is performed and the crack growth at different locations is analyzed in function of different tests parameters. Results obtained enable the definition of lifetime prediction models.
65

Etude de polymères pour l'utilisation en membranes de piles à combustible / Study of proton conducting polymeric membranes for use in fuel cells

Besson, Arthur 17 December 2014 (has links)
Les piles à combustible sont une technologie en pleine expansion dans le domaine du transport automobile.Les membranes polymères les plus utilisées actuellement dans ces systèmes sont celles à base de Nafion.Leur principal point faible se trouve dans leurs performances limitées au-delà de 80°C, où la membranedevient défaillante et l'eau ne peut plus assurer la conduction protonique. Le projet EUBECELL se proposede résoudre ce problème en mettant au point un système de pile à combustible fonctionnant à l'éthanol et àplus de 120°C. Cette thèse s'inscrit dans ce projet et se concentre sur l'élaboration de nouvelles membranespolymères conductrices de protons. Deux voies sont envisagées : l'amélioration des propriétés du Nafion àhaute température et le remplacement du Nafion par un polymère haute performance auquel on donne uneconductivité.L'amélioration du Nafion se fait par l'ajout de conducteurs liquides ioniques protiques (CLIPs), produitsayant donc une conductivité protonique venant s'ajouter à celle du Nafion. Un premier CLIP est synthétisé,caractérisé puis ajouté au Nafion et les performances des membranes obtenues mesurées. Les résultatsencourageants obtenus incitent à synthétiser d'autres CLIPs à partir de la même amine et en variant le contreion.D'autres mélanges Nafion-CLIPs sont ainsi synthétisés et caractérisés.Les polymères hautes performances étudiés ici pour remplacer le Nafion sont dans un premier temps despolysulfones sulfonées. Les polysulfones étant des polymères qui résistent aux températures élevées et lasulfonation leur donnant une conductivité. Pour conserver de meilleures propriétés après sulfonation, nousprocédons à une extrusion du film polymère suivi d'une sulfonation. Nous mettons donc au point unprotocole de sulfonation hétérogène. Les membranes obtenues sont ensuite caractérisées et leursperformances mesurées. Dans un deuxième temps nous travaillons sur des membranes macroporeuses, àforte tenue mécanique, que nous remplissons avec les CLIPs utilisés auparavant. Les membranes sont alorsaussi caractérisées et leurs performances mesurées. / Fuel cells are an ever-expanding technology in the field of automotive transport. The polymer membranesthat are currently the most widely used are Nafion-based membranes. Their weakest point is their drastic lossof performances beyond the threshold of 80°C, where the membranes fails and water cannot ensure protonconduction anymore. The EUBECELLproject sets to achieve making a fuel cell system functioning above120°C and using ethanol as a fuel. This thesis is part of the project and focus on elaborating new protonconductingpolymer membranes. Two main ways are explored: improving the performances of Nafion athigh temperature and replacing Nafion with conductivity-added high-performance polymers.Improving Nafion's performances is achieved by adding proton conducting ionic liquids (PCILs), productsthat have a proton conductivity that adds to Nafion's own. A first PCIL is synthesized, characterized and thenadded to Nafion, the resulting membranes' performances then measured. The encouraging results that weobtain makes us synthesize more PCILs, from the same amine than the first, varying the counter-ion. OtherNafion-PCIL mixes are made and then characterized.The high-performance polymer investigated for replacing Nafion are, first, sulfonated polysulfones.Polysulfones are high-temperature resistant polymers and sulfonation gives them conductivity. To keep betterproperties after the sulfonation, we proceed to extrude the films before sulfonating them. We elaborate anheterogeneous sulfonation protocol for them. The resulting membranes are then characterized and theirperformances measured. Second, we work on macroporous membranes, with high mechanical strength,which we fill with the PCILs that we previously used. The membranes are then also characterized and theirperformances measured.
66

Modelový animovaný klip pro projektovou výuku výtvarné a hudební výchovy na 2. stupni ZŠ\nl(prakticko-teoretická práce) / Model animated clip for project teaching of Arts and Music at secondary basic schools(practical-theoretical thesis)

MÁŠOVÁ, Anna January 2015 (has links)
This diploma thesis deals with animated clip and its application in teaching process, in particular in arts and music classes at secondary basic school, by means of project methodology. The theoretical part, besides project method, which is the center point of this work, also focuses on history of animated film, together with animated clip and its asset. Subsequently, the final section of the practical part applies the findings of the theoretical part. The final section of this diploma thesis is a model animated clip Adebars Reise "The Flight of a Stork" and a draft for the project education in arts and music education at secondary basic school, on the topic of animated clip.
67

Webový editor audia / Web Based Audio Editor

Kadlčík, Stanislav January 2013 (has links)
The Web Based Audio Editor thesis deals with the requirements specification, selection of technologies and with the implementation itself. The thesis uses modern approaches of HTML5 standards and is divided into the client and the server parts. Both the web application and the server are implemented in JavaScript. The Web based audio editor allows basic editing features like cut, shifting, deleting. All this in multiple audio tracks. The application runs in recent versions of the most widely used web browsers.
68

The Dynamic Fate of the Exon Junction Complex

Patton, Robert Dennison 13 November 2020 (has links)
No description available.
69

Optimalizace uložení projektorové čočky / Placement Optimization of Projector Lens

Bezděk, Matěj January 2014 (has links)
This diploma thesis deals with the creation of engineering design of holder of projector lens. The thesis is created in cooperation with department of development in Varroc Lighting Systems, s.r.o. Initial part provides a brief description of the development of lighting technology used in car´s headlamps. The following part describes solutions currently used in clamping the lens in holder. The main part of the thesis focuses on the design of holder of projector lens itself. Projector lenses testing provide critical values of cohesive failure of the lens material, which cannot be exceed during the process of lens fitting and its subsequent clamping. In the final part the engineering design is verified and optimized using finite element analysis.
70

Úloha vybraných vazoaktivních systémů v rozvoji chronického onemocnění ledvin / Contribution of particular vasoactive systems in the development of chronic kidney disease

Drábková, Natálie January 2019 (has links)
Chronic kidney disease (CKD) is a life-threating disease which arises as a frequent consequence of diabetes and hypertension. Since it is going on silently, CKD often progresses to the end-stage renal disease. It is therefore necessary to combat this disease especially due to the fact that the world population is growing old. The aim of this work was to determine the contribution of selected vasoactive systems contributing to the maintenance of high blood pressure in the developmental and established phase of CKD. Two models of CKD were used: 5/6 nephrectomy in Ren-2 transgenic rats (TGR) and stenosis of renal artery (2K1C) in Wistar rats. We demonstrated that renin-angiotensin system does not play so important role in blood pressure maintenance in both CKD models. By contrast, a more important role has sympathetic nervous system. During both the developmental and established phase of CKD, vasoconstrictor systems prevail above vasodilator NO-synthase effects. In fact, the role of NO-dependent vasodilation gradually decreased in nephrectomized TGR rats, while it was unchanged in Wistar rats with 2K1C hypertension.

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