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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.
651

A Statistical Analysis of the Lake Levels at Lake Neusiedl

Leodolter, Johannes January 2008 (has links) (PDF)
A long record of daily data is used to study the lake levels of Lake Neusiedl, a large steppe lake at the eastern border of Austria. Daily lake level changes are modeled as functions of precipitation, temperature, and wind conditions. The occurrence and the amount of daily precipitation are modeled with logistic regressions and generalized linear models.
652

Dépôts alignés de nanofils d'argent au sein de films multicouches pour des propriétés conductrices et optiques / Multilayer films of aligned silver nanowires for optical and conductive properties

Lemaire, Vincent 07 November 2017 (has links)
Cette thèse est consacrée à l’élaboration de films de nanofils d’argent orientés à l’aide de la technique de pulvérisation à incidence rasante. Couplée à la technique de dépôt couche-par-couche, il est possible de réaliser des films composés de plusieurs couches de nanofils d’argent orientées dans des directions différentes. Les films ainsi formés sont étudiés pour réaliser d’une part des supports conducteurs et transparents ordonnés et d’autre part pour réaliser des structures chirales aux propriétés optiques particulières. Une première étude est menée sur l’influence des différents paramètres de pulvérisation. Ils seront optimisés pour réaliser, dans un premier temps les échantillons transparents et conducteurs, puis dans un second, des structures chirales. Une seconde partie consiste à l’étude de structures hélicoïdales composées de plusieurs couches orientées de nanofils d’argent. Le dichroïsme circulaire de ces échantillons est étudié en fonction de différents paramètres de structure. Enfin une étude consistera à comparer les performances en tant que surface transparente et conductrice, de films orientés et d’argent sans ordre de nanofils. / This study consist in the elaboration of aligned films of silver nanowires by the Grazing Incidence Spraying (GIS) technique. Combined with the Layer-by-Layer (LbL) technique, it is possible to generate films composed of several aligned layers of silver nanowires with different directions of orientation. Optical and conductive properties of these films will be investigated to highlight the impact of these 3D ordered structures. The influence of different parameters of the GIS will be studied. These parameters will be optimized in ordrer to design samples for conductive and transparent films and to elaborate chiral structures. Chiral structures will be realized and their circular dichroism will be investigated in function of structural parameters. A last study will be realized about the influence of order for transparent and conductive electrodes by measuring performances of films with aligned and randomly deposed silver nanowires.
653

The Advent of an Artist-Composer Movement Exemplified by the Works of Saxophonists Colin Stetson, Evan Parker, and Contemporaries

Herald, Christopher R., Herald, Christopher R. January 2017 (has links)
Arising out of the avant-garde jazz tradition, a particular genre of solo saxophone music has emerged that combines stylistic attributes of avant-garde jazz and improvisation with minimalism, and is dependent on circular breathing, harmonic manipulation, and other techniques. To distinguish the music and the saxophonists and composers associated with it I have referred to this genre as "post avant-garde." With its roots ultimately in avant-garde jazz of the 1960s, this genre arose through the solo improvisation work of Evan Parker from the 1970s to present, and the music has since been an influence on the work of Colin Stetson and other artists, as well as composers including Gordon Fitzell and Alex Mincek. This document examines a previously unacknowledged but distinct genre of solo saxophone music, as well as the music of associated artists and composers.
654

Améliorations des performances d'outils de coupe pour la première transformation du bois / Cutting tools performances amelioration for sawmilling industry

Simonin, Guillaume 10 November 2010 (has links)
La société SIAT-BRAUN, premier de sciage résineux de France, présente une problématique industrielle liée à ses outils de coupe. Les scies débitant le bois doivent être les plus fines possibles afin de préserver la matière d'oeuvre, mais aussi très robustes pour supporter les conditions de coupe qui ne cessent de se durcir. La maîtrise de la matière première ainsi que des paramètres de réglage des machines sont des conditions sine-qua-none du bon travail des outils. Ainsi, nous arrivons à des situations limites où les règles actuelles ne répondent pas correctement aux exigences recherchées. Le mémoire comporte une étude technico-économique de la scierie et de son évolution, ainsi que du matériau bois employé. L'explication du fonctionnement de la ligne de sciage de l'entreprise, une des plus modernes, d'Europe, achève cette présentation.L'analyse des connaissances actuelles englobe les différents paramètres et calculs relatifs à l'usinage du bois, ainsi que les divers éléments composant une scie circulaire et ses géométries associées. Les interactions entre tous ces éléments sont aussi présentées. Le métier d'affûteur, personne en charge de la maintenance des outils et garante de leur bon fonctionnement, est présenté ainsi que des améliorations mises en place au niveau de la méthode ainsi que des machines de l'atelier.Pendant cette thèse, de nombreuses améliorations ont été réalisées sur les différents outils de coupe, afin de répondre aux exigences de la production en gardant une fiabilité la plus importante possible. La dernière partie proposera les améliorations restant à valider sur l'adéquation entre les matériaux et la géométrie angulaire des scies circulaires / SIAT-BRAUN is the largest industrial sawmill in France and faces typical industrial challenges with its sawing technologies.Wood saws must be as thin as possible, in order to maximize yield and save raw material and robust enough to endure tougher and tougher sawing conditions. Good raw material control and optimized machine parameterization are critical to ensure good results. The current theoretical background, does not always match these requirements and we are therefore always testing its limits.An economical and technical analysis of the sawmill and its evolution makes up the first part of this thesis. We will be detailing the key operations of one of the most modern sawmill in Europe.Current knowledge analysis must include the various parameters and calculations necessary to machine wood, as well as the different blade components and their geometric specifications. We will discuss the interactions between these elements. The job of the filer (the person in charge of tool maintenance) will also be discussed, as well as several improvements implemented in the workshop.Many improvements have been suggested and implemented while working on this thesis, in order to react to production needs while preserving reliability. In the last section of this thesis we will discuss several improvements that remain to be validated on how to best match appropriate cutting materials and blade geometry
655

Closed-loop supply chain : En studie av svenska detaljhandelsföretag inom modebranschen

Norberg, Filip, Carlsson, Niklas January 2017 (has links)
Den globala uppvärmningen anses idag vara ett av de största hoten mot vår planet. Vi människor är en stor bidragande orsak, efter årtionden av ständigt ökande utsläpp och gränslös konsumtion. Åtgärder måste genomföras inom samtliga sektorer i vårt samhälle. En av dessa sektorer är textilindustrin som årligen producerar mängder med nya produkter för att täcka kunders behov av ständig förnyelse. Som ett steg bort från det linjära slit-och-släng-samhället har företag börjat implementera cirkulära försörjningskedjor, s.k. closed-loop supply chains (CLSC). Denna studie undersöker hur svenska detaljhandelsföretag inom modebranschen arbetar med CLSC för att minska sin klimatpåverkan men även för att skaffa sig konkurrensfördelar. Detta görs genom en teorigenomgång som ligger till grund för en empirisk studie av fyra företag, där två av företagen studeras djupgående genom intervjuer med representanter från företagen. De två andra företagen har studerats på grundare nivå genom granskning av företagens hållbarhetsredovisning och hemsidor. Författarna undersöker även vilka drivkrafter och hot som företag ser med CLSC.
656

Interactions nanoparticules-protéines : caractérisation de la couronne protéique / Interactions nanoparticles-proteins : characterization of the protein corona

Capomaccio, Robin 18 December 2015 (has links)
De nos jours, les nanomatériaux sont utilisés dans de très nombreux domaines allant de l’agroalimentaire à la santé en passant par l’industrie automobile et le textile. Dans ce contexte, de nombreuses disciplines comme la métrologie et la nanotoxicologie se sont fortement développées. Dans les milieux biologiques, les protéines interagissent avec les nanoparticules pour former une couronne de protéines. Cette couronne de protéines joue un rôle important dans les interactions des nanoparticules avec leur environnement. Comprendre et caractériser les interactions des nanoparticules avec les protéines permettraient d’améliorer l’utilisation des nanoparticules dans différents domaines, notamment dans celui de la santé. Nous avons d’abord mis au point une méthode de purification des nanoparticules permettant de préserver la structure et la composition de la couronne protéique (Asymmetric flow field-flow fractionation, AF4). Nous avons ensuite caractérisé la couronne protéique associée à ces nanoparticules par plusieurs méthodes telles que la sédimentation centrifuge différentielle, la microscopie électronique, des méthodes basées sur la diffusion de la lumière (diffusion dynamique de la lumière (DLS) et la résonance plasmonique de surface localisée ou non), le dichroïsme circulaire classique et le Synchrotron Radiation Circular Dichroism (SRCD, Diamond, UK). Nous avons montré qu’une couronne d’albumine sérique humaine provoque une augmentation du diamètre hydrodynamique des nanoparticules d’or de 14 à 25,3 nm et une diminution de la densité d’un facteur 2. Ceci nous a permis de calculer que 19 molécules d’albumine en moyenne interagissent avec une nanoparticule. Les spectres de dichroïsme circulaire ont permis d’estimer que l’albumine conserve environ 70% de ses structures hélicoïdales lorsqu’elle est complexée avec les nanoparticules. Nous avons estimé l’affinité avec laquelle les nanoparticules d’or interagissent qui est d’environ 351 nM pour l’albumine et 513 nM pour la transthyrétine qui est riche en brins béta. Nous avons également optimisé une méthode de couplage de l’AF4 à un appareil de mesure de la diffusion dynamique de la lumière (DLS) pour améliorer la précision de la mesure du diamètre hydrodynamique des nanoparticules. Cette méthode précise et flexible permettra de caractériser de nombreuses modifications de surface des nanoparticules comme l’ajout de polyéthylène glycol, utilisées pour la conception de nano-médicaments / Nowadays, nanomaterials are used in numerous areas ranging from food to health through cars and textile engineering. In this context, many disciplines such as metrology and nanotoxicology, have been developed. In biological fluids, proteins interact with nanoparticles to form the protein corona, which plays an important role in mediating the interactions of the nanoparticles with their environment. Understanding and characterizing the interactions of nanoparticles with proteins and the corona structure would improve their use in various fields and particularly in the health sector. We have first developed a method based on Asymmetric Flow Field Flow Fractionation (AF4) for purifying gold nanoparticles preserving the structure and composition of the protein corona. Then we have characterized the protein corona associated to these nanoparticles by differential centrifugal sedimentation, electron microscopy, light scattering (dynamic light scattering, DLS), surface plasmon resonance (SPR) and localized SPR and by circular dichroism (classical CD and Synchrotron Radiation Circular Dichroism, SRCD, Diamond, UK). We have shown that human serum albumin corona increased the hydrodynamic diameter of the gold nanoparticles from 14 to 25.3 nm and decreases their density by a factor of 2. This enabled us to calculate that 19 albumin molecules on average interact with a nanoparticle. We have estimated by circular dichroism that albumin maintains about 70% of its helical structures when complexed with nanoparticles. The affinity between gold nanoparticles and proteins, is about 351 nM for albumin and 513 nM for transthyretin, which are enriched in helices and beta strands respectively. We have also optimized a coupling method between the AF4 system and the dynamic light scattering apparatus to improve the measurement accuracy of the hydrodynamic diameter of the nanoparticles. This accurate and flexible method will be helpful to characterize many surface modifications of the nanoparticles such as the addition of polyethylene glycol used for the design of nanodrugs
657

Investigating Early Village Community Formation and Development at Kolomoki (9ER1)

West, Shaun Eric 03 November 2016 (has links)
In southeastern North America, the Woodland period (ca. 1000 B.C. to A.D. 1050) was arguably witness to the first early village societies, and Kolomoki—located in southwestern Georgia—is among the largest villages during this interval. Though archaeologists recognize these communities as seminal developments in the course of human history, little attention has been paid to how they develop and vary internally. This thesis seeks to address these issues by focusing on the development and social construction of the early village community at Kolomoki. The results of an excavation program carried out within Kolomoki’s South Village affords a clearer picture of this understudied area, and provides supplemental collections to previous work at the site. New radiocarbon dates suggest a dynamic developmental sequence of Kolomoki’s village, starting as a relatively compact village sometime around the second century A.D., and growing to a massive scale around the seventh or eighth century A.D. Comparisons of various classes of material cultural provide evidence for contrasts between occupation along Kolomoki’s northern and southern enclosures, interpreted as differing uses of space by an internally differentiated community.
658

Deformation mechanisms beneath shallow foundations

McMahon, Brendan January 2013 (has links)
Shallow foundations can provide the most economical solution for supporting small-scale structures. The design approach is quite simple considering the ultimate bearing capacity and working-load settlement. Research has shown that settlement calculations, determined using a linear-elastic approach, usually govern the design but this approach is inappropriate because soil is highly non-linear, even at small strains. The result is that signifi cant discrepancies are observed between predicted and actual settlements. This uncertainty has seen the development of settlement-based approaches such as Mobilisable Strength Design (MSD). MSD uses an assumed undrained mechanism and accounts for soil non-linearity by scaling a triaxial stress-strain curve to make direct predictions of footing load-settlement behaviour. Centrifuge experiments were conducted to investigate the mechanisms governing the settlement of shallow circular foundations on clay and saturated sand models. Clay model tests were performed on soft or rm kaolin beds, depending on its pre-consolidation. Sand model tests were performed on relatively loose Hostun sand saturated with methyl-cellulose to slow consolidation. One-dimensional actuators were developed to apply footing loads through dead-weight or pneumatic loading. A Perspex window in the centrifuge package allowed digital images to be captured of a central cross-section, during and after footing loading. These were used to deduce soil displacements by Particle Image Velocimetry which were consistent with footing settlements measured directly. Deformation mechanisms are presented for undrained penetration, consolidation due to transient flow, as measured by pore pressure transducers, and creep. A technique was developed for discriminating consolidation settlements from the varying rates of short and long-term creep of clay models. Using MSD, a method for predicting the undrained penetration of a spread foundation on clay was proposed, using database results alone, which then provided estimates of creep and consolidation settlements that follow. The importance of the undrained penetration necessitated further investigation by using the observed undrained mechanism as the basis of an ellipsoidal cavity expansion model. An upper-bound energy approach was used to determine the load-settlement behaviour of circular shallow foundations on linear-elastic and non-linear clays, with yield defined using the von Mises' yield criterion. Linear-elastic soil results were consistent with those obtained from nite element analyses. The non-linear model, as described by a power-law, showed good agreement with both centrifuge experiment results and some real case histories. The single design curve developed through this model for normalised footing pressure and settlement could be used by practising engineers based on existing soil correlations or site investigations.
659

Applications Of Method Of Characteristics And Upper Bound Limit Analysis To Different Bearing Capacity Problems

Ghosh, Priyanka 12 1900 (has links) (PDF)
No description available.
660

Conjugate Natural Convection In Horizontal Annuli

Narambhatla Sambamurthy, * 10 1900 (has links) (PDF)
No description available.

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