• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 38
  • 25
  • 21
  • 10
  • 4
  • 3
  • 1
  • Tagged with
  • 114
  • 114
  • 50
  • 43
  • 39
  • 32
  • 27
  • 25
  • 19
  • 19
  • 18
  • 17
  • 17
  • 16
  • 15
  • 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.
101

Mateřská škola v Příboře / Kindergarten in Příbor

Murgašová, Dominika Unknown Date (has links)
The subject of this master’s thesis is a project documentation for development of a nursery school. The nursery school is situated on the outskirts of the city Příbor. The school is designed as a two-storey building and includes 4 classrooms, with total capacity reaching 60 pupils. The perimeter wall consists of Porotherm clay block walling system. The ceiling framework uses a combination of two systems; the prestress hollow core slabs Spiroll and reinforced concrete monolithic blocks. The roof is designed as a single skin cladding with a flat, green roof. The external thermal insulation composite system (Etics) is proposed for the insulation of the building. The outer walls are partially cladded with timber. Additionally, the combination of white rendering and timber cladding will form a modern looking building that fits within a new housing development. Furthermore, the plan includes an outside playground, with allotments and parking spaces on the premises for the use of a nursery school.
102

Studies of particle and atom manipulation using free space light beams and photonic crystal fibres

Gherardi, David Mark January 2009 (has links)
Light can exert optical forces on matter. In the macroscopic world these forces are minuscule, but on the microscopic or atomic scale, these forces are large enough to trap and manipulate particles. They may even be used to cool atoms to a fraction of a degree above absolute zero. This thesis details a number of experiments concerned with the optical manipulation of atoms and micron-size particles using free space light beams and photonic crystal fibres. Two atom guiding experiments are described. In the first experiment, a spatial light modulator is used to generate higher blue-detuned azimuthal Laguerre-Gaussian LG) beams, which are annular beams with a hollow core. These LG beams are then used to guide laser cooled rubidium-85 atoms within the dark core over a distance of 30 mm. The second atom guiding experiment involves attempting to guide laser cooled and thermal rubidium atoms through a hollow-core photonic crystal fibre using red-detuned light. Hollow-core photonic crystal fibres are fibres that are able to guide light with low attenuation within a hollow core. For this experiment a hot wire detection system was designed, along with a number of complex vacuum systems. The first dual-beam fibre trap for micron-size particles constructed using endlessly single-mode photonic crystal fibre (ESM-PCF) is described. The characteristics of dual-beam fibre traps are governed by the fibres used. As ESM-PCF has considerably different properties in comparison to conventional single- or multimode fibres, this dual beam ESM-PCF trap exhibits some novel characteristics. I show that the dual beam ESM-PCF trap can form trapping, repulsive and line potentials; an interference-free ‘white light’ trap; and a dual-wavelength optical conveyor belt.
103

Génération de paires de photons corrélés par mélange à quatre ondes spontané dans des fibres microstructurées à coeur liquide / Generation of correlated photon pairs by spontaneous four-wave mixing in liquid-filled hollow-core photonic crystal fibres

Barbier, Margaux 13 November 2014 (has links)
Une technique couramment employée pour développer les sources de paires de photons corrélés indispensables au domaine des télécommunications quantiques repose sur le processus non linéaire de mélange à quatre ondes, qui peut avoir lieu directement dans le cœur d’une fibre optique. Cette architecture fibrée permet de s’adapter au mieux aux besoins des réseaux de communications quantiques (en particulier en minimisant les pertes par couplage lors de la connexion de la source aux autres composants du réseau). L’utilisation d’une fibre microstructurée plutôt que d’une fibre de silice conventionnelle permet d’ajuster les propriétés de dispersion de la fibre et d’optimiser l’efficacité du processus non linéaire. Cependant, les sources fibrées usuelles, à cœur de silice, présentent une limitation majeure : leur pureté quantique est fortement dégradée par la diffusion Raman spontanée, qui survient elle aussi dans le cœur en silice de la fibre. Pour s’affranchir de ce problème, notre idée est de remplacer le cœur en silice par un cœur liquide, en utilisant une fibre microstructurée à cœur creux rempli d’un liquide non linéaire. Nos recherches nous ont ainsi conduits à faire la première démonstration expérimentale de génération de paires de photons corrélés dans une fibre à cœur liquide, et à montrer que, grâce aux propriétés Raman particulières des liquides (dont le spectre Raman se présente en général sous la forme de raies très fines), il était possible de réduire de plusieurs ordres de grandeur le niveau de diffusion Raman spontanée dans la source. Ce travail ouvre donc la voie au développement de sources de paires de photons corrélés fibrées de très haute qualité quantique. / Quantum telecommunication technologies rely on correlated photon pair sources, which are often based on the third-order nonlinear process of spontaneous four-wave mixing in silica-core photonic crystal fibres. A fibred architecture is advantageous because it minimizes the coupling losses between the optical source and the other components of quantum communication networks. Moreover, using a photonic crystal fibre rather than a conventional silica fibre offers the possibility of improving the photon generation (thanks to a small effective core area) and extending the wavelength coverage (thanks to dispersion management through the microstructuration design). However, the performances of silica-core photonic crystal fibre sources are limited in terms of quantum purity, because of the ubiquitous spontaneous Raman scattering process, which is a source of uncorrelated broadband noise photons in silica. We propose an original solution to this Raman problem by replacing the silica core by a liquid core, thanks to a hollow-core photonic crystal fibre filled with a nonlinear liquid. We actually performed the first experimental demonstration of the generation of correlated photon pairs in a liquid-core fibre, and demonstrated that, thanks to the specific Raman properties of liquids (which usually exhibit thin-line Raman spectra), it is possible to reduce the Raman noise level by several orders of magnitude. This work opens the way for the development of high quantum quality correlated photon pair fibred sources.
104

Sources lasers innovantes à base de micro-capsules photoniques et par nano-structuration de milieux gazeux / Innovative laser sources based on pohotonic micro-cells aand by nano-structuration of gaz media

Chafer, Matthieu 19 September 2018 (has links)
Depuis leur avènement, les fibres à cristal photonique à cœur creux ont prouvé leur capacité à convertir des fréquences avec une haute efficacité, notamment en jouant sur le phénomène de diffusion Raman stimulée. Dans le cadre d’un contrat CIFRE entre la société GLOphotonics et l’institut de recherche Xlim, ce projet de thèse a consisté à développer ces fibres afin d’améliorer leurs performances optiques pour cibler deux voies d’applications: une industrielle pour proposer un laser compact multi-ligne dans le visible et dans l’UV et une seconde plus fondamentale pour réaliser un synthétiseur d’onde optique. L’amélioration de ces performances repose sur l’exacerbation de l’inhibition du couplage entre le mode du coeur d’air et les modes de silice de la gaine. Pour cela deux types de micro-structures ont été explorées à savoir une maille Kagomé et une maille tubulaire. Plusieurs fibres ont été alors fabriquées démontrant des performances records sur toute une gamme de longueurs d’onde (8,5 dB/km à 1 µm, 7,7 dB/km à 750 nm, 13,8 dB/ km à 549 nm, et autour de 70 dB/km à 355 nm). Concernant la fonctionnalisation de ces fibres, des micro-capsules photoniques ont été conçues et réalisées permettant à la fois de palier au problème de la perméabilité de la silice au gaz (stabilité de la conversion dépassant 12 mois) et de démontrer une conversion de 26 lignes dans le visible. Un produit industriel nommé CombLas a alors été produit puis appliqué à une étude de cytométrie en flux pour étudier l’influence du taux de répétition du laser de pompe. Ce produit a également été étendu à la gamme spectrale de l’UV avec la génération de 24 lignes entre 225-400 nm. Enfin, des travaux plus fondamentaux ont été réalisés consistant à développer un synthétiseur d’onde optique à base de génération Raman dans ces fibres creuses. Une nouvelle dynamique a été observée démontrant le piégeage de molécules d’hydrogène par un réseau optique auto-assemblé de puits de potentiel ultra-profonds et nanométriques. Cela permis de générer un régime Lamb-Dicke de la diffusion Raman stimulée. Des signatures sub-Doppler usuellement vues dans les atomes froids ont été mesurées avec des largeurs de bandes plus étroites de plus de 5 ordres de grandeurs par rapport à ce qui est prédit dans la littérature. Finalement, cette largeur de bande a été optimisée d’un ordre de grandeur en jouant sur la longueur de la fibre et la pression de l’hydrogène. / Since their advent, hollow-core photonic crystal fibers have proved to be highly efficient for frequency conversion, especially via by playing with stimulated Raman scattering. Within the frame work of a CIFRE contract between the firm GLOphotonics and the Xlim research institute, this thesis project has consisted in developing these fibers to enhance their optical performances, in order to target two different field of applications: an industrial one to offer a a compact multi-line laser in the visible and UV and a second more fundamental one to realize a optical wave synthesizer. The amelioration of these performances relies on the exacerbation of the inhibition of the coupling between the air core mode and the silica cladding modes. Two types of micro-structures have been explored, a Kagomé and a tubular lattice. Several fibers have been fabricated demonstrating record performances on all a wavelength range (8.5 dB/km at 1 µm, 7.7 dB/km at 750 nm, 13.8 dB/km at 549 nm, and around 70 dB/km at 355 nm). Concerning the functionalization of the fibers, photonic micro-cells have been designed and realized enabling to overcome the problem the permeability of silica to gas (conversion stability over 12 months) and demonstrate a conversion to 26 lines in the visible. An industrial product coined CombLas has been made and used for flow cytometry in order to study the influence of the repetition rate of the pump laser. This product has also been extended to the UV range with 24 lines generated between 225-400 nm. Also, more fundamental research has been realized consisting in developing an optical wave synthesizer based on Raman generation in hollow core fibres where a new dynamic has been observed demonstrating the trapping of hydrogen molecules by an auto-assembled optical lattice of ultra-deep and nano-metric potential wells. This configuration has enabled to generate a Lamb-Dicke regime of stimulated Raman scattering. Sub-Doppler signatures usually found in cold atoms have been measured with linewidths narrower than 5 orders of magnitude than what is predicted in the literature. Finally, this linewidth has been optmised of an order of magnitude by plaing on the length of the fiber and the pressure of hydrogen.
105

Laser-Induced Damage and Ablation of Dielectrics with Few-Cycle Laser Pulses

Talisa, Noah Brodzik January 2020 (has links)
No description available.
106

Mateřská škola / Kindergarten

Berényiová, Christiána January 2019 (has links)
The subject of this diploma thesis is design and project documentation of a kindergarten in Velké Pavlovice. It is a separately standing structure with two floors and partial basement located in slightly sloping terrain. The building is constructed of sand-lime blocks with contact thermal insulation, supported by strip foundations. Ceiling construction is made of prestressed hollow-core slabs. This object is roofed by a simple, flat, extensive roof. This kindergarten is designed for 40 children divided into two sections which are located right in the 1st floor together with food delivery. The technical room is in the basement. The common room, multipurpose classroom and headquarters are situated on the 2nd floor. Disposition is proposed in accordance with operation of kindergarten.
107

Mateřská škola / Kindergarten

Ambrožová, Martina January 2020 (has links)
The final thesis is focused on design of functional unit od Kindergarten in Křenovice (district Vyškov). The object is subdivided to 3 functional parts. The middle part is designed as a two-storey, remaining two parts are single-storey. Whole object is without cellart. This object is formed from two separate class for fifteen children each and the middle part is design for technical facilities . For every class are two teachers and in total one a head teacher. For the preparation food a cleaningup there are three employees. In the object is one office of speech therapy with barrier free access. The roofing of object is design as a warm vegetation flats roofs. The object is design as a masonry system of sand-lime block with contact thermal insulation system.
108

Mateřská škola / Kindergarten

Neradová, Barbora January 2020 (has links)
The subjekt of this diploma thesis is design and project documentation of a kindergarten in city Jihlava. New building is situated in the western part of the city HorníKosov. The kindergarten is designed for preschool education 48 children from 3 to 7 years. The building is without cellar. The building has two floors. In the 1st floor there are two separate classes with sanitary facilities and facilities for teachers. Two separate classes have a common dining room with kachen facilities and sanitary facilities for her employees. In the second floor there is lenguage class for 12 children, storage, directors office, office of speech therapy and sanitary facilities. The object is base on concrete foundation strips. The vertical load-bearing constructions are made of ceramics bricks. The walls are insulated with combination of contact thermal insulation system and ventilated facade with facade cladding of cement-bonded particle board. Ceiling construction is made of prestressed hollow-core slabs. Roof construction over single-storey parts of the building is designed as a vegetation flat roof. Roof construction over the two-storey part of the building is designed as a warm flat roof. Next to the object is situated parking slots for cars. Altogether is designed 13 places, which 1 is designed for disabled people.
109

Centrum volnočasových aktivit / Center of leisure activities

Kaňovský, Michal Unknown Date (has links)
This diploma thesis presents a project documentation for construction of a center of leisure activities. It's construction site located on the outskirts of town Třebíč, "Na Kopcích" street. The building is composed from the two visual and three service parts which are connected to each other. On the left side in first floor there is a bowling with services and the second floor will serve for sport activities of jumping, spinning or relax massages. On the right side of building will be usable for education or for leisure activities. The building is designed as a two floors with partial basement. The construction system is formed by longitudinal wall system with precast hollow core slab or reinforced concrete slab. The structure is based on strip foundations with walls of permanent formwork. External wall is based on clay brick of therm type. The staircase is designed as prefabricated element or cast-in-place reinforced concrete. The roof is constructed as warm flat green roof with expanded polystyrene with screed to fall.
110

Základní škola / Elementary school

Králíková, Zuzana January 2015 (has links)
Diploma thesis solves the design of the elementary school. The building is situated in Letohrad in region Pardubice. The design of the school building contains small sport hall for pupils and for possible public access. Dinning room and the kitchen are the parts of the building. The object is designed as structural masonry system, ceramic bricks with external thermal insulation composite system. Building does not have a basement. The object is divided to three parts, teaching part, dining room with kitchen and sports hall with facilities. The building has two-storey in the teaching part, the remaining part is a single-storey with vegetation roof. All roofs are designed as a warm flat roof. The building is designed for capacity 150 pupils. Building ventilation is provided by air-conditioning equipment. Entrance to the building is barrier-free, it is installed a building elevator inside.

Page generated in 0.0408 seconds