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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.
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Showing 1 to 8 of 8 (0.013 seconds)| 1 |
Vad kan kamerans perspektiv och illustrationens komposition ha för effekt för hur karaktären från League of legends är iscensatt? : Vad kameravinklar kan uttrycka i film och bild berättande / What effect can the camera's perspective and the composition of the illustration have on how the character from League of legends is staged? : What camera angles can express in film and image storytellingVikman, Elvira January 2022 (has links)
Uppsatsen analyserar kameravinklar i förhållande till illustrationer som finns i ett onlinespel. Diskussion förs kring fyra bilder. Detta görs utifrån en bildanalys med inslag av semiotisk analys. Undersökningen kunde inte visa på om kameravinklar i sig själva kan uttrycka visuellt berättande eller ej. Dock visar studien att kameravinklar kan öka det visuella berättandet som en bild har. / The essay analyzes camera angles in relation to illustrations found in an online game. Discussion is conducted around four pictures. This is done on the basis of an image analysis with elements of semiotic analysis. The study could not show whether camera angles in themselves can express visual narrative or not. However, the study shows that camera angles can increase the visual narrative meaning of an image.
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Ordre de rayure des cuprates supraconducteurs dans le modèle de HubbardMercure-Boissonnault, Pierre January 2015 (has links)
Ce mémoire contient l'essentiel de la recherche de Pierre Mercure-Boissonnault sur l'ordre de rayure dans les cuprates supraconducteurs. Cette recherche consistait à vérifier à l'aide du modèle de Hubbard et de méthodes numériques (VCA et CDMFT) si l'ordre de rayure est présent dans les plans cuivre-oxygène de ces matériaux et comment l'ordre de rayure interagit avec la supraconductivité. De plus, plusieurs amas différents sont utilisés dans le but de permettre l'observation de différentes formes d''ordre de rayure (centré sur les sites, centré sur les liens et diagonal). Finalement, les paramètres du modèle de Hubbard sont modifiés afin d'observer l'effet sur l'ordre de rayure par rapport à l'antiferromagnétisme.
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Elektronicky řiditelné aktivní prvky k realizaci oscilátorů a funkčních generátorů / Electronically adjustable active elements for the realization of oscillators and function generatorsBokůvka, Tomáš January 2014 (has links)
This thesis is focused on the design, analysis and realization of new oscillator and generator circuits using electronically adjustable active elements. In the opening discussion the aspects of distribution, proposal, properties and oscillation conditions of generators and oscillators are theoretically described. Next, there are presented some electronically adjustable active elements which appear to be suitable for construction of the oscillators and generators. This covers in particular the Operational Transconductance Amplifier OTA, Voltage Control Amplifier VCA and Digitally Adjustable Current Amplifier DACA. Using these elements the six oscillators and two functional generators are presented. Simulation results and design methods are included. Next part is focused on practical realization and measurement. At the end of the thesis the measurement and simulation results are discussed and compared.
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Shaping the Climate Action trajectory within the Fashion Industry : a case study of a Small Medium Sized EnterpriseKristjónsdóttir, Marta Karen January 2019 (has links)
The apparel and footwear industry’s contribution to global greenhouse gas (GHG) emissions is one of the fifth largest per industry, equal to that of livestock, after electricity and heat, oil and gas, agriculture, and transportation (Ellen MacArthur Foundation, 2017). For industry-wide emissions reduction, investing in renewable energy and energy efficiency programs across highest impacting life cycle phases offer the most effective solution. However, identifying the highest impacting life cycles phases shows varied results depending on the particular type of business model under examination. This paper responds to the lack of existing data and empirical research on how to accurately measure, report and reduce carbon emissions across the highly complex and globally interconnected apparel value chain. This is done through a single case study investigation of an Icelandic fashion brand. A hybrid approach of a standard Life Cycle Assessment (LCA) and the Sustainable Global Value Chain (SGVC) functions to produce a Hotspot Identification Tool (HIT) to establish a holistic portrayal of business operations in relation to emission impacts and level of controllability across Scopes. The conceptual analysis and qualitative results identify the most relevant emission hotspots to lie within the company’s privately owned manufacturing facilities, as well as the procurement phase, due to its direct connection with and influence on material production, user phase, and end-of-life. The main obstacle in this pursuit is identified as restriction of resources in terms of time, capital and expertise. It is suggested that this be overcome by joining a Multi-Stakeholder Initiative where resources and expertise is pooled in a pre-competitive manner to reach common objectives. The investigation further suggests a need for global fashion brands to leverage their influential position on down- and upstream activities across the value chain, i.e. with their supply chain partners and consumers. I argue that fashion brands play an integral role in supporting local efforts to build a decarbonisation pathway towards climate neutral economies on a global scale.
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Advanced Cluster Methods for Correlated-Electron SystemsFischer, André 12 January 2016 (has links) (PDF)
In this thesis, quantum cluster methods are used to calculate electronic properties of correlated-electron systems. A special focus lies in the determination of the ground state properties of a 3/4 filled triangular lattice within the one-band Hubbard model. At this filling, the electronic density of states exhibits a so-called van Hove singularity and the Fermi surface becomes perfectly nested, causing an instability towards a variety of spin-density-wave (SDW) and superconducting states. While chiral d+id-wave superconductivity has been proposed as the ground state in the weak coupling limit, the situation towards strong interactions is unclear.
Additionally, quantum cluster methods are used here to investigate the interplay of Coulomb interactions and symmetry-breaking mechanisms within the nematic phase of iron-pnictide superconductors. The transition from a tetragonal to an orthorhombic phase is accompanied by a significant change in electronic properties, while long-range magnetic order is not established yet. The driving force of this transition may not only be phonons but also magnetic or orbital fluctuations. The signatures of these scenarios are studied with quantum cluster methods to identify the most important effects.
Here, cluster perturbation theory (CPT) and its variational extention, the variational cluster approach (VCA) are used to treat the respective systems on a level beyond mean-field theory. Short-range correlations are incorporated numerically exactly by exact diagonalization (ED). In the VCA, long-range interactions are included by variational optimization of a fictitious symmetry-breaking field based on a self-energy functional approach. Due to limitations of ED, cluster sizes are limited to a small number of degrees of freedom.
For the 3/4 filled triangular lattice, the VCA is performed for different cluster symmetries. A strong symmetry dependence and finite-size effects make a comparison of the results from different clusters difficult. The ground state in the weak-coupling limit is superconducting with chiral d+id-wave symmetry, in accordance to previous renormalization group approaches. In the regime of strong interactions SDW states are preferred over superconductivity and a collinaer SDW state with nonuniform spin moments on a quadrupled unit cell has the lowest grand potential. At strong coupling, inclusion of short-range quantum fluctuations turns out to favor this collinear state over the chiral phase predicted by mean-field theory. At intermediate interactions, no robust conclusion can be drawn from the results.
Symmetry-breaking mechanisms within the nematic phase of the iron-pnictides are studied using a three-band model for the iron planes on a 4-site cluster. CPT allows a local breaking of the symmetry within the cluster without imposing long-range magnetic order. This is a crucial step beyond mean-field approaches to the magnetically ordered state, where such a nematic phase cannot easily be investigated. Three mechanisms are included to break the fourfold lattice symmetry down to a twofold symmetry. The effects of anisotropic magnetic couplings are compared to an orbital ordering field and anisotropic hoppings. All three mechanisms lead to similar features in the spectral density. Since the anisotropy of the hopping parameters has to be very large to obtain similar results as observed in ARPES, a phonon-driven transition is unlikely.
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Advanced Cluster Methods for Correlated-Electron SystemsFischer, André 27 October 2015 (has links)
In this thesis, quantum cluster methods are used to calculate electronic properties of correlated-electron systems. A special focus lies in the determination of the ground state properties of a 3/4 filled triangular lattice within the one-band Hubbard model. At this filling, the electronic density of states exhibits a so-called van Hove singularity and the Fermi surface becomes perfectly nested, causing an instability towards a variety of spin-density-wave (SDW) and superconducting states. While chiral d+id-wave superconductivity has been proposed as the ground state in the weak coupling limit, the situation towards strong interactions is unclear.
Additionally, quantum cluster methods are used here to investigate the interplay of Coulomb interactions and symmetry-breaking mechanisms within the nematic phase of iron-pnictide superconductors. The transition from a tetragonal to an orthorhombic phase is accompanied by a significant change in electronic properties, while long-range magnetic order is not established yet. The driving force of this transition may not only be phonons but also magnetic or orbital fluctuations. The signatures of these scenarios are studied with quantum cluster methods to identify the most important effects.
Here, cluster perturbation theory (CPT) and its variational extention, the variational cluster approach (VCA) are used to treat the respective systems on a level beyond mean-field theory. Short-range correlations are incorporated numerically exactly by exact diagonalization (ED). In the VCA, long-range interactions are included by variational optimization of a fictitious symmetry-breaking field based on a self-energy functional approach. Due to limitations of ED, cluster sizes are limited to a small number of degrees of freedom.
For the 3/4 filled triangular lattice, the VCA is performed for different cluster symmetries. A strong symmetry dependence and finite-size effects make a comparison of the results from different clusters difficult. The ground state in the weak-coupling limit is superconducting with chiral d+id-wave symmetry, in accordance to previous renormalization group approaches. In the regime of strong interactions SDW states are preferred over superconductivity and a collinaer SDW state with nonuniform spin moments on a quadrupled unit cell has the lowest grand potential. At strong coupling, inclusion of short-range quantum fluctuations turns out to favor this collinear state over the chiral phase predicted by mean-field theory. At intermediate interactions, no robust conclusion can be drawn from the results.
Symmetry-breaking mechanisms within the nematic phase of the iron-pnictides are studied using a three-band model for the iron planes on a 4-site cluster. CPT allows a local breaking of the symmetry within the cluster without imposing long-range magnetic order. This is a crucial step beyond mean-field approaches to the magnetically ordered state, where such a nematic phase cannot easily be investigated. Three mechanisms are included to break the fourfold lattice symmetry down to a twofold symmetry. The effects of anisotropic magnetic couplings are compared to an orbital ordering field and anisotropic hoppings. All three mechanisms lead to similar features in the spectral density. Since the anisotropy of the hopping parameters has to be very large to obtain similar results as observed in ARPES, a phonon-driven transition is unlikely.
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Geochemie Porifera-reicher Mud Mounds und Mikrobialithe des Mittel- und Oberdevons (Westaustralien, Nordfrankreich) / Geochemistry of Porifera-rich mud mounds and microbialites of the Middle and Upper Devonian (Western Australia, Northern France)Hühne, Cathrin 07 November 2005 (has links)
No description available.
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Postglazialer Anstieg des Meeresspiegels, Paläoklima und Hydrographie, aufgezeichnet in Sedimenten der Bermuda inshore waters / Postglacial rise of sea level, palaeoclimate and hydrography, recorded in sediments of the Bermuda inshore watersVollbrecht, Rüdiger Dr. 13 January 1997 (has links)
No description available.
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