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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.
41

Světlo a osvětlení / Light and lighting

Malá, Veronika January 2011 (has links)
MALÁ V. Light and Lighting /Thesis/ Prague 2010. Charles University, Faculty of education, Department of Art education 109 pages My diploma thesis is focused on a light, lighting and their space effect. The aim of this work was to describe use of light and lighting in photographs, films, scenography and in architecture; also it deals with the Czech design of light and lighting with applications of unconventional materials. The second part of this thesis is comprised of my very own lamp design and the use of light theme in art lessons.
42

Experimentální ovlivnění líhnutí diapauzujících stádií perloočky Daphnia obtusa / Influence of experimental conditions on hatching of diapausing stages of the cladoceran Daphnia obtusa

Sailerová, Martina January 2010 (has links)
Diapause is often an adaptation for survival during periods of harsh environmental conditions. Some diapausing stages do not terminate the dormancy once the favourable conditions are restored. Such prolonged diapause may be enforced by environment if a diapausing stage cannot be reached by the cues inducing termination of dormancy. However, it may also be an advantageous bet-hedging strategy to allow only a fraction of dormant stages produced in any given season to hatch the next time conditions become favourable. I tested whether such strategy can be observed in hatching patterns of dormant eggs of Daphnia obtusa - a cladoceran occurring in small Central European temporary waters. I investigated the influence of intensity of illumination on hatching success, and effect of isolating the eggs encased in ephippia from the sediment. Fraction of eggs terminating diapause, fraction of embryos successfully leaving the egg membranes, and timing of the response were assessed at 15 ˚C under four intensities of illumination (100% = 35µmol.m2 .s-1 , 75%, 50%, 25%; photoperiod 12h light: 12h dark) and in complete darkness for 21 days. My results support previous suggestions that there is no genetically-fixed bet-hedging strategy in D. obtusa. I observed high proportion of eggs which terminated diapause in all...
43

Evoluční algoritmy pro návrh optické části svítidla / Evolutionary Algorithms for the Design of Luminaire Optics

Drázdová, Zuzana January 2021 (has links)
The goal of this thesis was to explore the possibilities of using evolutionary algorithms to design components with specific purpose. We examined the process of designing an optimal shape of reflector from a highly reflective metal sheet. The main goal of this reflector is to evenly distribute light from a light emitting diode. We created a simplified model of the environment, where our component should be used. Then we used the evolutionary approach to find a suitable reflector shape for an existing device. One selected solution was manufactured and its properties measured. We also used the developed program to search for a design of an optical part for a completely new device proposal. Both tasks were accompanied by a number of problems that originated in an inaccurate task specification and general disparity between the fields of evolutionary computation and industrial components development. We provided an analysis of issues we encountered and presented solutions that can be applied to other similar tasks.
44

Minimalistický objektově orientovaný "ray tracer" / Minimalistic Object-Oriented Ray Tracer

Roženský, Mário January 2008 (has links)
This thesis brings an overview about scene rendering using the ray tracing method. It describes aspects used when creating the application which uses this method such as intersection computation, lighting and shading models etc. It also describes the basic algorithm used for rendering one frame. Each class of the object oriented design is described. There is also detail explanation what is the purpose of the each class in the model and what are the most important used methods. The work also contains demonstration application showing the usage of model in practice.
45

Zpětný výpočet křivek svítivosti svítidel určených pro osvětlování komunikací / Reverse calculation of the luminous intensity curves of street lighting luminaires

Knápková, Dagmar January 2019 (has links)
This master´s thesis deals with the reverse calculation of luminous curves for roads according to ČSN EN 13201. The thesis is divided into the theoretical and the practical part. The theoretical part describes the basic requirements and procedures for calculating the luminous curves. The practical part describes the program, created in the Matlab environment, which is designed for the practical calculation of the ideal luminous curve, for each situation given by the user. Further particular example of the calculation is given.
46

Využití jasového analyzátoru pro kvantifikaci umělého světla v nočním prostředí / Use of Luminance Analyser for the Quantification of Artificial Light at Night

Novák, Filip January 2021 (has links)
This diploma thesis deals with obtrusive light and its measurement, especially with the help of luminance analyzers. In particular, the necessary theoretical basis for the design of a measuring methodology for obtrusive light or veil brightness of the sky is laid here. This mainly includes the division of obtrusive light and its manifestations, a description of the effects of obtrusive light on the environment, selected organisms and the human body. Also described herein are the biological mechanisms of the human body that are affected by light as such. Attention is also paid to streetlights, its classification and methods of reducing obtrusive light, as well as methods of measuring brightness and brightness analyzers. Last but not least, the night sky is also measured using the LumiDISP luminance analyzer and subsequent data are evaluated using the proposed method.
47

Stanovení spotřeby elektrické energie pro veřejné osvětlení / Analysis of Electric Power Consumption of Public Lighting

Varmuža, Jan January 2011 (has links)
The thesis deals with analysis of the public lighting system from the point of view of light sources and luminaries. It focuses on the specifics of the lighting systems such as lighting for pedestrian crossings or decorative lighting. It analyzes the energy consumption depending on daylight and how it manifests a shift sunrise and sunset on the consumption of electricity. The work clarifies how the model can be simplified sunrise, sunset for the entire Czech Republic. Based on the distribution of municipalities with population over 10,000 and modeling of sunrise and sunset calculation is carried out power consumption of lighting systems and compared to the total consumption of the Czech Republic. Simplification is an estimate of the consumption of electricity to villages to 10 000 people on the basis of the estimate, the final consumption of electricity for public lighting for the entire Czech Republic.
48

Ekonomická efektivnost a finanční proveditelnost projektu realizovaného obcí / Economic Efficiency and Financial Feasibility of Project Realized by Municipality

Vik, Vladimir January 2014 (has links)
This diploma thesis deals with a public lighting and its direct impact on the financial management of the municipality. Within this analysis the basic methods and ways, which the municipality use in the field of a management and a maintenance of the public lighting system, were described. The eventual form of the reconstruction of the public lighting in the Černožice village was also proposed. In a response to this proposal possible ways of financing this investment project were subsequently outlined. The secondary aim of this thesis was to create a concise database of implemented projects of the reconstruction in other municipalities and comparison of these results.
49

Moderní techniky realistického osvětlení v reálném čase / Modern Methods of Realistic Lighting in Real Time

Szentandrási, István January 2011 (has links)
Fyzikálně přijatelné osvětlení v reálném čase je často dosaženo použitím aproximací. Současné metody často aproximují globální osvětlení v prostoru obrazu s využitím schopností moderních grafických karet. Dva techniky z této kategorie, screen-space ambient occlusion a screen-space directional occlusion jsou popsány detailněji v této práci. Screen-space directional occlusion je zobecněná verze screen-space ambient occlusion s podporou jednoho difúzního odrazu a závislostí na směrové informaci světla. Hlavním cílem projektu bylo experimentování s těmito metodami. Pro uniformní distribuci náhodných vzorek pro obě metody byla použita Halton sekvence. Pro potlačení šumu je použita bilaterální filtrace, která bere do úvahy geometrické vlastnosti scény. Metody jsou dál zrychleny použitím nižších rozlišení pro výpočet. Rekonstrukce výsledků do původní velikosti pro vytvoření konečného obrazu je realizována pomoci joint bilateral upsamplingu. Kromě metod globálního osvětlení byly v práci použity aj metody pro mapování stínů a HDR osvětlení.
50

Měření kvality osvětlení na operačních sálech / Measurement of operating room lights quality

Rovná, Tereza January 2016 (has links)
This thesis is focused on measuring the quality of lighting in operating rooms. Operating lights are very demanding in terms of quality requirements for each parameter, so it is important to specify exactly these parameters and check them regurarly. To measure the quality of the light source, was used a special kit from Maquet. Measurement procedure was not as accurate as it was for operating lighting need, therefore, this work includes a proposal to improve the measurement of quality lighting in operating theaters. In cooperation with University Hospital Brno Bohunice University Hospital Motol and the company Maquet measured nine operating lights, each light were compared in terms of parameters such as maximum light intensity, light distribution in the surgical field. In each category were selected several lighting, which reached the best results. The various parameters were compared with values declared by the manufacturer.

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