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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.
181

Nosná ŽB konstrukce objektu hotelu / Load bearing RC structure of hotel building

Macourková, Klára January 2014 (has links)
The thesis deals with the static solution of monolitic reinforced concrete concstruction of hotel building. Subject of the solutions is reinforced concrete monolithic point – supported ceiling slab, columns, foundations and staircase. Assesment of these structures by the first ultimate state – carrying capacity.
182

Chráněné bydlení Rajhrad - stavebně technologický projekt / Sheltered housing Rajhrad - construction technology project

Kubišová, Jana January 2016 (has links)
The aim of thesis is construction-technology project of sheltered housing in Rajhrad. Parts of the thesis are technical report of site facilities, technological prescription for monolithic ceiling construction, inspection and test plan for monolithic ceiling construction, proposal of mechanical assemblies and transport relations, occupational safety and health, environmental plan, compared of monolithic and prefabricated staircases, the draft contract for work and binding rules for use of the building, financing construction cost, schedule.
183

Wellness penzion / Wellness pension

Pokorný, David January 2022 (has links)
The subject of the diploma thesis is the processing of project documentation for the construction of wellness pension. This building is designed in a medium sloping terrain on the edge part of the Rajhrad city. The building has 3 floors and garage in the basement. Object is divided into 2 parts, the first part consists a restaurant and 2 floors for temporary accommodation in 14 rooms for 45 customers. The second part consists wellness for accommodated and also for other outside customers. The roof is designed single skin with vegetation area (extensive). The project includes a solution of paved areas and access to the underground garage, fencing, water connection, sewage connection, rainwater conection including a retention tank and overflow into the rainwater sewerage. The construction system of the building is based on reinforced concrete footings connected to foundation strips in the places of the cladding, follow up reinforced concrete columns. The ceiling structures, including hidden girders and stairs, are made of monolithic, reinforced concrete. Vertical load-bearing structures are designed from POROTHERM ceramic blocks. The vertical structures of the basement are designed from lost formwork. The building's ventilation system is divided into four parts, the first part is for wellness, the second part is for restaurant and pension, third part is for kitchen, last part is for fire protected escape route.
184

Obvodní oddělení policie ČR v Brně - Bohunicích, příprava realizace stavby / District Police Department of the Czech Republic in Brno-Bohunice, Preparation for Construction

Dubecký, Tomáš January 2022 (has links)
The aim of the diploma thesis is to prepare the construction called the District Police Department of the Czech Republic in Brno, Bohunice. The diploma thesis contains a technical report on the construction technology project, which deals with architectural and construction design solutions, coordination situation and transport routes, where critical points are assessed time and financial plan of construction, where all construction objects are described with their time and financial schedule, a study of the implementation of the main construction stages, which addresses the various stages of construction. The diploma thesis contains a technical report, item budget, plan for the establishment and liquidation of buildings and drawings of construction site equipment for each stage, design of the main construction machinery for the construction. A detailed time plan of the main building, a plan of its supply of materials for the rough construction was prepared for the given construction. Furthermore, the work contains a technological regulation for a reinforced concrete monolithic staircase, which is related to the control and test plan for a reinforced concrete monolithic staircase. The next assignment deals with the item budget of the main building for the rough construction, the drawing of the formwork for the reinforced concrete monolithic staircase and the economic assessment and evaluation of construction cranes.
185

Planetárium s kavárnou / Planetarium with coffee

Vlčková, Sabina January 2016 (has links)
Thesis on "Planetarium with coffee" is processed in the form of project documentation for construction. The proposed facility is designed as a two-storeyed without basement with the main ground plan dimensions of 52,8 x 27,47 m and is located near the village Lošov close to Olomouc. The building is operationally divided into a part intended for public entrance and a part for operation and maintenance. Loadbearing structural system is reinforced concrete monolithic skeleton based on monolithic reinforced concrete foundation footings. Ceiling structure consists of reinforced concrete, monolithic, locally supported, cross reinforced floor slab. Vertical external walls are made of ceramic blocks with contact thermal insulation system. Part of the front rounded facade is designed as glass fronted. The building is covered by a warm flat roof. Roof cladding consists of vegetation layers, walkable terrace or non-walkable structure of roof cladding. The planetarium itself is covered by a reinforced concrete dome with a thermal insulation layer of plates of foamed glass. Fillings of doors and windows are made of aluminum profiles with isolating triple glazing. The building meets the requirements for barrier-free use of buildings.
186

Onduleur triphasé à structure innovante pour application aéronautique / Innovative three-phase Inverter structure for aircraft applications

Guepratte, Kevin 14 March 2011 (has links)
En aéronautique, les contraintes sont telles que la masse des filtres peut représenterjusqu'à 50% de la masse totale du convertisseur. Ces dernières années, les convertisseursmulticellulaires parallèles entrelacés et magnétiquement couplés ont conduit à améliorer lesperformances des convertisseurs (densité de puissance, efficacité, dynamique,...). Denombreuses topologies de filtrages entrelacés existent, l'objectif principal de cette étude est detrouver parmi ces topologies celles qui sont les mieux adaptées à la réalisation d’un onduleurde tension 110Veff / 400Hz triphasé 25kVA. Il est démontré que le choix du type de matériaumagnétique a un impact déterminant sur le poids, le volume et les pertes du convertisseur. Quidit parallélisation, dit multiplication du nombre de semi-conducteurs. Ces nouvelles structuresdoivent garantir à la fois un rendement élevé, une masse faible et une continuté defonctionnement, même en cas de panne d’un semiconducteur de puissance ou de sacommande. Mais coupler les phases entre elles, impose un lien indissociable qui peut êtrenuisible au fonctionnement de la structure en cas de dysfonctionnement. Des solutionsexistent et sont abordées dans l’étude. Enfin, la réalisation pratique d'un prototype semiindustrielde convertisseur triphasé utilisant des transformateurs interphases est présentée. Ils’agit d’un onduleur réseau avionique triphasé avec reconstruction de neutre pour fonctionneren déséquilibré. Les résultats expérimentaux démontrent l’avantage d’un convertisseur / In aeronautics field, the constraints are such as the mass of the filters can represent upto 50% of the total mass of the converter. During the last years, magnetic coupled interleavedconverters enhances performances (power density, efficiency, transient response). It existeseveral possibilities for use interleaved coupled topologies that use inter-phase transformerexist, the main objective of this study is to find among these topologies the best adaptedconfiguration in the context of a three-phase voltage inverter 110Veff/400Hz 25kVA. Thechoice of the magnetic material type has a great impact on determining the weight, thevolume and the losses of the converter. Parallelization leads to increase the semiconductornumber. These new structures must guarantee at the same time a raised efficiency, a low massand a great reliability, even in the event of case of breakdown of a power semiconductor orhis driver circuit. But coupleing the phases between themselve, imposes a dangerous stronglink on the structure operation in event of default. Solutions exist and are presented in thestudy. Lastly, the implementation of a semi-industrial of three-phase converter using interphasestransformers is performed. This inverter has been desinging to be use on a three-phaseavionics inverter network with rebuilding of neutral in case of unbalancing. Experimentalresults show the advantage of an interleaved converter compared with a conventional solution.
187

Nouvelle formulation monolithique en élément finis stabilisés pour l'interaction fluide-structure / Novel monolithic stabilized finite element method for fluid-structure interaction

El Feghali, Stéphanie 28 September 2012 (has links)
L'Interaction Fluide-Structure (IFS) décrit une classe très générale de problème physique, ce qui explique la nécessité de développer une méthode numérique capable de simuler le problème FSI. Pour cette raison, un solveur IFS est développé qui peut traiter un écoulement de fluide incompressible en interaction avec des structures différente: élastique ou rigide. Dans cet aspect, le solveur peut couvrir une large gamme d'applications.La méthode proposée est développée dans le cadre d'une formulation monolithique dans un contexte Eulérien. Cette méthode consiste à considérer un seul maillage et résoudre un seul système d'équations avec des propriétés matérielles différentes. La fonction distance permet de définir la position et l'interface de tous les objets à l'intérieur du domaine et de fournir les propriétés physiques pour chaque sous-domaine. L'adaptation de maillage anisotrope basé sur la variation de la fonction distance est ensuite appliquée pour assurer une capture précise des discontinuités à l'interface fluide-solide.La formulation monolithique est assurée par l'ajout d'un tenseur supplémentaire dans les équations de Navier-Stokes. Ce tenseur provient de la présence de la structure dans le fluide. Le système est résolu en utilisant une méthode élément fini et stabilisé suivant la formulation variationnelle multiéchelle. Cette formulation consiste à décomposer les champs de vitesse et pression en grande et petite échelles. La particularité de l'approche proposée réside dans l'enrichissement du tenseur de l'extra contraint.La première application est la simulation IFS avec un corps rigide. Le corps rigide est décrit en imposant une valeur nul du tenseur des déformations, et le mouvement est obtenu par la résolution du mouvement de corps rigide. Nous évaluons le comportement et la précision de la formulation proposée dans la simulation des exemples 2D et 3D. Les résultats sont comparés avec la littérature et montrent que la méthode développée est stable et précise.La seconde application est la simulation IFS avec un corps élastique. Dans ce cas, une équation supplémentaire est ajoutée au système précédent qui permet de résoudre le champ de déplacement. Et la contrainte de rigidité est remplacée par la loi de comportement du corps élastique. La déformation et le mouvement du corps élastique sont réalisés en résolvant l'équation de convection de la Level-Set. Nous illustrons la flexibilité de la formulation proposée par des exemples 2D. / Numerical simulations of fluid-structure interaction (FSI) are of first interest in numerous industrial problems: aeronautics, heat treatments, aerodynamic, bioengineering... Because of the high complexity of such problems, analytical study is in general not sufficient to understand and solve them. FSI simulations are then nowadays the focus of numerous investigations, and various approaches are proposed to treat them. We propose in this thesis a novel monolithic approach to deal with the interaction between an incompressible fluid flow and rigid/ elastic material. This method consists in considering a single grid and solving one set of equations with different material properties. A distance function enables to define the position and the interface of any objects with complex shapes inside the volume and to provide heterogeneous physical properties for each subdomain. Different anisotropic mesh adaptation algorithms based on the variations of the distance function or on using error estimators are used to ensure an accurate capture of the discontinuities at the fluid-solid interface. The monolithic formulation is insured by adding an extra-stress tensor in the Navier-Stokes equations coming from the presence of the structure in the fluid. The system is then solved using a finite element Variational MultiScale (VMS) method, which consists of decomposition, for both the velocity and the pressure fields, into coarse/resolved scales and fine/unresolved scales. The distinctive feature of the proposed approach resides in the efficient enrichment of the extra constraint. In the first part of the thesis, we use the proposed approach to assess its accuracy and ability to deal with fluid-rigid interaction. The rigid body is prescribed under the constraint of imposing the nullity of the strain tensor, and its movement is achieved by solving the rigid body motion. Several test case, in 2D and 3D with simple and complex geometries are presented. Results are compared with existing ones in the literature showing good stability and accuracy on unstructured and adapted meshes. In the second, we present different routes and an extension of the approach to deal with elastic body. In this case, an additional equation is added to the previous system to solve the displacement field. And the rigidity constraint is replaced with a corresponding behaviour law of the material. The elastic deformation and motion are captured using a convected level-set method. We present several 2D numerical tests, which is considered as classical benchmarks in the literature, and discuss their results.
188

Etude de l'influence de la structure et de la composition de matériaux hybrides monolithiques sur les propriétés optiques (luminescence et absorption non-linéaire) / Study of structure and composition influence of monolithic hybrid materials on optical properties (luminescence and non-linear absorption)

Chateau, Denis 09 July 2013 (has links)
Le procédé sol-gel permet la réalisation de matériaux optiquement performants et la possibilité d’intégrer diverses molécules dans ces systèmes ouvre les portes à des applications dans de nombreux domaines. Nous nous sommes intéressés en particulier à la réalisation de matériaux sol-gel monolithiques, fortement dopés avec des molécules actives, dans le cadre de la réalisation de limiteurs optiques performants dans le visible et dans l’infrarouge.La mise au point de procédés et de matrices sol-gel compatibles avec divers types de chromophores a tout d’abord été effectuée. Une investigation des paramètres expérimentaux et de la nature des précurseurs influençant la microstructure des matériaux a été réalisée, ainsi que la mise au point de méthodes de gélification accélérée capables de piéger efficacement les chromophores dans les matrices sol-gel même à de très hautes concentrations.Le dopage des matrices obtenues avec différents chromophores pour la limitation optique dans le visible et dans l’infrarouge s’en est suivi, avec une étude de l’impact des matrices sur les propriétés optiques des dopants. L’évaluation des performances en limitation a révélé les performances exceptionnelles des systèmes étudiés dans le visible, et des résultats prometteurs pour l’infrarouge.Enfin, la synthèse de nanoparticules d’or isotropes et anisotropes et leur incorporation dans les matériaux préparés a permis de mettre en évidence des effets d’exaltation importants sur les propriétés non-linéaires des chromophores au sein des matrices sol-gel et permettent d’améliorer les performances en limitation de manière considérable. / Sol-gel chemistry is a potent approach for the realization of optical materials, and enables chromophores incorporation in materials making the soft process a gateway for many applications. In this work, we focused on monolithic sol-gel materials, heavily doped with optically active chromophores for the realization of solid-sate optical power limiting devices in the visible and near-infrared range.The elaboration and optimization of compatibles sol-gel matrices with those chromophores was the first step. An investigation of the different synthesis parameters and the nature of the precursors on the materials nanostructure were done, together with the creation of high speed gelation processes to enable the incorporation of very high chromophores contents.Using these approaches, the preparation of highly doped materials for optical power limiting in the visible and the near infrared range was successful, and the impact of the matrices on chromophores properties was studied. Evaluation of optical limiting properties of these materials revealed exceptional performance in the visible range and promising results for the NIR range.Finally, isotropic and anisotropic gold spheres were prepared and incorporated inside the materials. The resulting composites showed enhancements of the non-linear properties of the chromophores inside the matrix, and dramatic improvement of the optical power limiting efficiency was achieved.
189

Titanium Dioxide Based Microtubular Cavities for On-Chip Integration

Madani, Abbas 03 March 2017 (has links) (PDF)
Following the intensive development of isolated (i.e., not coupled with on-chip waveguide) vertically rolled-up microtube ring resonators (VRU-MRRs) for both active and passive applications, a variety of microtube-based devices has been realized. These include microcavity lasers, optical sensors, directional couplers, and active elements in lab-on-a-chip devices. To provide more advanced and complex functionality, the focus of tubular geometry research is now shifting toward (i) refined vertical light transfer in 3D stacks of multiple photonic layers and (ii) to make microfluidic cooling system in the integrated optoelectronic system. Based on this motivation, this PhD research is devoted to the demonstration and the implementation of monolithic integration of VRU-MRRs with photonic waveguides for 3D photonic integration and their optofluidic applications. Prior to integration, high-quality isolated VRU-MRRs on the flat Si substrate are firstly fabricated by the controlled release of differentially strained titanium-dioxide (TiO2) bilayered nanomembranes. The fabricated microtubes support resonance modes for both telecom and visible photonics. The outcome of the isolated VRU-MRRs is a record high Q (≈3.8×10^3) in the telecom wavelength range with optimum tapered optical fiber resonator interaction. To further study the optical modes in the visible and near infrared spectral range, μPL spectroscopy is performed on the isolated VRU-MRRs, which are activated by entrapping various sizes of luminescent nanoparticles (NPs) within the windings of rolled-up nanomembranes based on a flexible, robust and economical method. Moreover, it is realized for the first time, in addition to serving as light sources that NPs-aggregated in isolated VRU-MRRs can produce an optical potential well that can be used to trap optical resonant modes. After achieving all the required parameters for creating a high-quality TiO2 VRU-MRR, the monolithic integration of VRU-MRRs with Si nanophotonic waveguides is experimentally demonstrated, exhibiting a significant step toward 3D photonic integration. The on-chip integration is realized by rolling up 2D pre-strained TiO2 nanomembranes into 3D VRU-MRRs on a microchip which seamlessly expanded over several integrated waveguides. In this intriguing vertical transmission configuration, resonant filtering of optical signals at telecom wavelengths is demonstrated based on ultra-smooth and subwavelength thick-walled VRU-MRRs. Finally, to illustrate the usefulness of the fully integrated VRU-MRRs with photonic waveguides, optofluidic functionalities of the integrated system is investigated. In this work, two methods are performed to explore optofluidic applications of the integrated system. First, the hollow core of an integrated VRU-MRR is uniquely filled with a liquid solution (purified water) by setting one end of the VRU-MRRs in contact with a droplet placed onto the photonic chip via a glass capillary. Second, the outside of an integrated VRU-MRR is fully covered with a big droplet of liquid. Both techniques lead to a significant shift in the WGMs (Δλ≈46 nm). A maximum sensitivity of 140 nm/refractive index unit, is achieved. The achievements of this PhD research open up fascinating opportunities for the realization of massively parallel optofluidic microsystems with more functionality and flexibility for analysis of biomaterials in lab-on-a-tube systems on single chips. It also demonstrates 3D photonic integration in which optical interconnects between multiple photonic layers are required.
190

Cromatografia a líquido por injeção sequencial para a determinação de herbicidas triazínicos e metabólitos da atrazina explorando o uso de cela de longo caminho óptico e monitoramento on-line em estudos de adsorção / Sequential injection liquid chromatography for the determination of triazine herbicides and metabolites of atrazine exploring the use of long optical pathlength flow cell and on line monitoring of adsorption studies

Urio, Ricardo de Prá 16 May 2011 (has links)
Estudou-se o emprego da Cromatografia a Líquido por Injeção Seqüencial (SIC) explorando o uso de uma cela de longo caminho óptico com guia de onda (LCW) de 100 cm para a melhora dos limites de detecção (LOD) e quantificação (LOQ) na determinação de atrazina (ATR), propazina (PRO) e simazina (SIM). Para isto, utilizou-se uma fase móvel com composição de 44:56 (v v-1) metanol : tampão acetato de amônio 1,25 mM, pH 4,7, coluna monolítica e a detecção espectrofotométrica em 238 nm. Obtiveram-se valores de LOD e LOQ, respectivamente, de 1,76 e 5,86 µg L-1 para ATR, 4,51 e 15 µg L-1 para PRO e 2,25 e 7,5 µg L-1 para SIM. Com o emprego da cela de longo caminho óptico os valores de LOD ficaram abaixo dos recomendados pela US-EPA, que permite para águas potáveis uma concentração de 3 µg L-1 para ATR, 4 µg L-1 para SIM e 10 µg L-1 para PRO. Realizaram-se estudos de adsorção de SIM, PRO e ATR e seus metabólitos desisopropilatrazina (DIA), desetilatrazina (DEA) e 2-hidroxiatrazina (HAT) em solo, ácido húmico e solo modificado com ácido húmico. Para isso foi utilizado um sistema de monitoramento on-line composto por um filtro tangencial e uma bomba peristáltica para circulação da suspensão. Foram realizados estudos cinéticos em duas etapas e, em ambas, foi utilizado um mix dos compostos com concentração inicial de 1,0 mg L-1 e gradiente de eluição passo a passo para a separação dos compostos utilizando três fases móveis com composições de 15 ou 28, 40 e 50% (v v-1) metanol : tampão acetato de amônio 1,25 mM pH 4,7. Na primeira etapa o tempo de contato entre triazinas e adsorventes foi de 90 min. Na segunda etapa foi utilizado apenas o solo como adsorvente e o tempo de contato foi de 24 h. Para a primeira etapa do estudo só foi possível aplicar modelo cinético de pseudo-segunda ordem, o qual permitiu estimar os valores de massa adsorvida de triazina por massa de adsorvente, sendo que o ácido húmico é o material com maior capacidade adsortiva (1470 ± 43µg g-1 para DIA a 2380 ± 51 µg g-1 para PRO). O composto mais adsorvido em solo é PRO (26,5 ± 0,1 µg g-1). A presença de ácido húmico no solo aumentou a adsorção de ATR (de 19,4 ± 0,7 para 23 ± 2 µg g-1), de HAT (10,9 ± 0,7 para 18 ± 2 µg g-1) e de PRO (26,5 ± 0,7 para 29,8 ±0,2 µg g-1), mas diminuiu a adsorção de SIM e não afetou DIA e DEA. No estudo com tempo de contato de 24 h foi possível aplicar modelos de pseudo-primeira e segunda ordem. Os resultados obtidos confirmaram a maior adsorção de PRO, seguidos da ATR. HAT, SIM, DEA e DIA apresentaram as menores taxas de adsorção em solo, sendo que os dois últimos apresentaram uma tendência de dessorção após 4 h de contato, tendo maior potencial de lixiviação para corpos d\'água próximos aos locais de aplicação. / This work describes the use of Sequential Injection Liquid Chromatography (SIC) coupled to a long path length optical flow cell with 100 cm long Liquid Core Waveguide (LCW) to improve the limits of detection (LOD) and quantification (LOQ) for determination of atrazine (ATR), propazine (PRO) and simazine (SIM). Separation was achieved with a mobile phase composition of 44:56 (v v-1) methanol:1.25 mM ammonium acetate buffer, pH 4.7, monolithic column and spectrophotometric detection at 238 nm. The values of LOD and LOQ were, respectively, 1.76 and 5.86 µg L-1 for ATR, 4.51 and 15 µg L-1 for PRO and 2.25 and 7.5 µg L-1 for SIM. The LOD values achieved with the employment of long optical path cell were lower than those recommended by US-EPA, which allows for drinking water, maximum concentration levels of 3 µg L-1 for ATR, 4 µg L-1 for SIM and 10 µg L-1 for PRO. Adsorption of SIM, PRO and ATR, as well as their metabolites desisopropylatrazine (DIA), desethylatrazine (DEA) and 2-hidroxyatrazine (HAT) on soil, humic acid and soil modified with humic acidic was studied. An on-line monitoring system was assembled, composed of a tangential filter and a peristaltic pump for circulation of the suspension. Kinetic studies were carried out in two steps, and in both, it was used a mix of compounds with initial concentration of 1,0 mg L-1 and a stepwise gradient elution for separation of the compounds using three mobile phases with compositions of 15 or 28, 40 and 50% (v v-1) methanol: 1.25 mM ammonium acetate buffer, pH 4.7. In the first step the contact time between triazines and adsorbents was 90 minutes. In a second study made only with soil, the contact time was 24 h. Data obtained in the first stage of the study was only fitted to pseudo-second order kinetic equation, which allowed one to estimate the values of the adsorbed mass of triazine per mass of adsorbent. Humic acid was the material with higher adsorptive capacity (from 1470 ± 43 µg g-1 for DIA to 2380 ± 50 µg g-1 for PRO). In soil, PRO exhibited the highest adsorption (26.5 ± 0.1 µg g-1). The presence of humic acid in the soil increased adsorption of ATR (19.4±0.7 to 23±2 µg g-1), HAT (10.9 ± 0.7 to 18 ± 2 µg g-1) and PRO (26.5 ± 0.7 to 29.8 ± 0.2 µg g-1), but decreased adsorption of SIM, not affecting DIA and DEA. In the study with contact time of 24 h, it was possible apply pseudo-first and pseudo-second order equations for SIM, ATR and PRO. The results confirmed the greatest adsorption of PRO, followed by ATR. HAT, SIM, DEA and DIA had low rates of adsorption on soil, the latter two showed a trend of desorption after 4 h of contact, having the greatest potential for leaching to water bodies near to the places of application.

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