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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.
1001

Osvětlovací systémy v ostrovních aplikacích / Lighting systems in off-grid applications

Lengyel, Ladislav January 2015 (has links)
Aim of the master's thesis is at first to explain appropriate light sources and lighting systems; secondly present suitable light sources selection for lighting a small space and design of an off-grid system. The last part consists of an overview about alternative energy transformations to light energy. The first of these three major themes focuses on the analysis of light sources suitable for use in applications with accumulation together with data on energy efficiency and the utilization efficiency associated with them, concentrating on their consumption and possible energy saving lighting within small applications. It ends with a description and calculations of electricity energy indicators for different types of rooms. The second and main part of the thesis is focusing on suitable light sources selection for off-grid systems and impacts on humans and the environment associated with it. An object representing a small application has been created in RELUX® software with suitable light sources installed in it. For this scene, appropriate parts of off-grid systems were selected, which could be used to power the proposed lighting. The last theme consists of a brief about alternative sources, most of which are still in development or existing only at a theoretical level. All of these alternative sources are having a possible application in the future.
1002

Energetické hodnocení budov / Energy assessment of buildings

Velísková, Eva January 2012 (has links)
The master’s thesis deals with energy assessment of buildings according to a current valid legislature. In the first part the energy assessments problems are solved. The next part solves the energy concept of the educational building, Pavilion P4, AdMaS centre of Faculty of Civil Engineering of BUT, in the form of project documentation. In the part of thesis there is a simulation characterizing dynamic behavior of building. The thesis point is the evaluation of energy balance and a draft of measures leading to the power consumption decrease.
1003

Horský hotel / Mountain hotel

Kyceltová, Lucie January 2014 (has links)
The theme of this work is the building design, brand new mountain hotel with wellness services in Spindleruv Mlyn. The plot is located in a quiet part of town, near a wooded area and form a river Labe.V designed hotel is located three floors above ground level of the building is solved attic space. Roofed by a wooden roof false hip roof. Ground unsophisticated form a geometric shape, which layout is divided into sections. On the ground floor wellness facilities, a portion of the input dopňkovými with hotel services, floor is done mainly for accommodation, as well as the attic. Hotel is equipped with a slightly sloping plot in the construction of houses and other hotels. All living spaces are naturally ventilated and illuminated. The supporting structure consists Liapor system. The appearance of the hotel is in line with the surroundings.
1004

Simulace vlnění vody v reálném čase / Simulation of Water Waves in Real-Time

Pilch, Martin January 2011 (has links)
Task of this thesis is creation of real-time simulation of the water waves. It is implemented on Mac OS X platform using OpenGL. This thesis is based on height map surface. Heigh map is computed by suming of sinusoids with complex, time-based amplitudes. Fast Fourier transformation, Phillips spectrum and gauss random generator are used to solve this problem. The thesis is also implemented on iOS platform and optimized to run on mobile devices thanks to using programmable graphic pipeline and other drawing and computing optimizations.
1005

Návrh opatření pro snížení energetické náročnosti prodejny potravin / Proposal of measures for reducing energy demands of food stores

Julinová, Patricie January 2016 (has links)
The master thesis deals with measures to reduce energy performance of grocery store building. Model of the grocery store is evaluated according to a recommended energy values specified by Czech standards and according to the real values of the actual consumption. These values are compared. Final building analysis for a proposal measures to reduce energy consumption is based on the invoices of the real consumption and on the experimental assignments. Experimental measurements are the Blower door test of the tightness of the building envelope, the measures with the thermovision camera and the measuring of the illumination intensity. The most efficient proposal is extended to the whole model network of the food shops in the Czech Republic.
1006

Denní osvětlení prostor světlovody / Daylighting of spaces with light guides

Machová, Petra January 2016 (has links)
This thesis deals with the illuminance space through light guide. It describes it's basic principles, technical features and ways of differentiation between the technologies. The thesis also includes latest methods for evaluation of illumination of space supported by various computer simulations.
1007

Großflächige Abscheidung organischer Leuchtdioden und Nutzung optischer Verfahren zur in situ Prozesskontrolle

Eritt, Michael 11 November 2010 (has links)
In der vorliegenden Arbeit wird die großflächige Abscheidung von organischen Leuchtdioden (OLED) für Beleuchtungsanwendungen in einer neuartigen Beschichtungsanlage vorgestellt. Ausgehend von den speziellen Anforderungen an gleichförmige Schichtdickenverteilung und hohe Abscheideraten für die organischen Schichten, sind die Verfahren der thermischen Vakuumverdampfung (VTE) und der organischen Dampfphasenabscheidung (OVPD) auf Substraten der Größe 370 x 470 mm² unter Fertigungsbedingungen kombiniert. Die Quellensysteme der Anlage wurden hinsichtlich der Verteilung des Materialauftrages und der Oberflächenrauigkeit qualifiziert. Die Kontrolle der Schichteigenschaften ist bei der organischen Dampfphasenabscheidung durch Variation der Parameter Substrattemperatur und Abscheiderate in einem weiten Bereich möglich. Die in situ Kontrolle der Schichtdicke mittels spektroskopischer Reflektometrie wird vorgestellt. Ein Messsystem ist in die Beschichtungsanlage integriert und abgeschiedene Schichten charakterisiert worden. Die Arbeit zeigt, dass die genaue Bestimmung der Dicke einzelner Schichten oder ganzer Schichtstapel mit diesem Verfahren möglich ist und zur ex situ Ellipsometrie vergleichbare Ergebnisse liefert. Um robuste OLED-Bauelemente herzustellen, wird eine organische Kurzschlussunterdrückungsschicht eingeführt, die konform mittels der OVPD-Technologie abgeschieden wird. Die strombegrenzenden Eigenschaften dieser Schicht wirken Defektströmen innerhalb der OLED entgegen. Die reproduzierbare Herstellung von 100 x 100 mm² großen, weißes Licht emittierenden OLED-Modulen mit mittleren Leistungseffizienzen von über 13 lm/W zeigt das Potential dieser Technologie. / The thesis deals with the large area deposition of organic light-emitting diodes (OLED) for lighting applications with a novel deposition tool. The special needs of film thicknesses homogeneity and high deposition rates for organic layers request the combination of thermal vacuum deposition (VTE) and organic vapour phase deposition (OVPD) processes to fabricate OLEDs on 370 x 470 mm² substrates. The deposition sources are qualified regarding layer homogeneity and morphology of the deposition processes. The layer properties are controlled in a wide range by the variation of the organic vapour phase deposition parameters: substrate temperature and deposition rate. The in situ determination of the substrate thickness is shown by the application of spectroscopic reflectometry. The thesis demonstrates the thickness analysis of single and multi-layer stacks by reflectometry. The data fit well to ex situ ellipsometry. Robust OLED devices with an additional short-circuit protection layer deposited by OVPD technology are introduced. The current limiting properties of this layer reduce the leakage currents in the OLED device. The fabrication of 100 x 100 mm² white emitting OLED modules with power efficiencies about 13 lm/W shows the great potential of the manufacturing technology.
1008

Extraction and Integration of Physical Illumination in Dynamic Augmented Reality Environments

A'aeshah Abduallah Alhakamy (9371225) 16 December 2020 (has links)
Although current augmented, virtual, and mixed reality (AR/VR/MR) systems are facing advanced and immersive experience in the entertainment industry with countless media forms. Theses systems suffer a lack of correct direct and indirect illumination modeling where the virtual objects render with the same lighting condition as the real environment. Some systems are using baked GI, pre-recorded textures, and light probes that are mostly accomplished offline to compensate for precomputed real-time global illumination (GI). Thus, illumination information can be extracted from the physical scene for interactively rendering the virtual objects into the real world which produces a more realistic final scene in real-time. This work approaches the problem of visual coherence in AR by proposing a system that detects the real-world lighting conditions in dynamic scenes, then uses the extracted illumination information to render the objects added to the scene. The system covers several major components to achieve a more realistic augmented reality outcome. First, the detection of the incident light (direct illumination) from the physical scene with the use of computer vision techniques based on the topological structural analysis of 2D images using a live-feed 360<sup>o</sup> camera instrumented on an AR device that captures the entire radiance map. Also, the physics-based light polarization eliminates or reduces false-positive lights such as white surfaces, reflections, or glare which negatively affect the light detection process. Second, the simulation of the reflected light (indirect illumination) that bounce between the real-world surfaces to be rendered into the virtual objects and reflect their existence in the virtual world. Third, defining the shading characteristic/properties of the virtual object to depict the correct lighting assets with a suitable shadow casting. Fourth, the geometric properties of real-scene including plane detection, 3D surface reconstruction, and simple meshing are incorporated with the virtual scene for more realistic depth interactions between the real and virtual objects. These components are developed methods which assumed to be working simultaneously in real-time for photo-realistic AR. The system is tested with several lighting conditions to evaluate the accuracy of the results based on the error incurred between the real/virtual objects casting shadow and interactions. For system efficiency, the rendering time is compared with previous works and research. Further evaluation of human perception is conducted through a user study. The overall performance of the system is investigated to reduce the cost to a minimum.
1009

Opportunities from Disaster: The Case for Using The Circular Economy in Debris Management

Toy W Andrews (11176893) 23 July 2021 (has links)
Following a grounded theory research model, the research uncovered and presented the state of debris recycling to a national association of demolition contractors to measure their willingness and attitudes towards the growing trend in the circular economy and adapting their business models to incorporate it into their own contracts. The first part was finding the deficiencies in the current model based on government reports and through interviews with county-level emergency managers. Second, successful businesses that already use the circular economy design in their operations were used as exemplars to emulate and their opinions and suggestions were discussed. The outputs of the emergency managers and the successful businesses was folded into the third phase of the research with surveys to the membership of the National Demolition Association (NDA) with multiple-choice, scalar questions and open-ended, opinion-heavy questions throughout. The findings were reported back to the head of the partnering organization, the NDA, to focus outreach, training, and policy advocacy concentration for the national organization as a whole, but to related and tangentially-connected industries to their own.
1010

OLEDs: Light-emitting thin film thermistors revealing advanced selfheating effects

Fischer, Axel, Koprucki, Thomas, Glitzky, Annegret, Liero, Matthias, Gärtner, Klaus, Hauptmann, Jacqueline, Reineke, Sebastian, Kasemann, Daniel, Lüssem, Björn, Leo, Karl, Scholz, Reinhard 29 August 2019 (has links)
Large area OLEDs show pronounced Joule self-heating at high brightness. This heating induces brightness inhomogeneities, drastically increasing beyond a certain current level. We discuss this behavior considering 'S'-shaped negative differential resistance upon self-heating, even allowing for 'switched-back' regions where the luminance finally decreases (Fischer et al., Adv. Funct. Mater. 2014, 24, 3367). By using a multi-physics simulation the device characteristics can be modeled, resulting in a comprehensive understanding of the problem. Here, we present results for an OLED lighting panel considered for commercial application. It turns out that the strong electrothermal feedback in OLEDs prevents high luminance combined with a high degree of homogeneity unless new optimization strategies are considered.

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