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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.
81

[en] BREAKUP OF TWO-LAYER LIQUID FILMS / [pt] QUEBRA DE UM FILME DE LÍQUIDO COMPOSTO POR DUAS CAMADAS

PEDRO HENRIQUE SOUZA CALDERANO 23 August 2021 (has links)
[pt] Filmes finos de líquido estão presentes em uma variedade de sistemas e aplicações. Estamos interessados em filmes compostos por duas camadas, que são comuns no processo de revestimento por cortina. No revestimento por cortina, o líquido cai de uma matriz formando uma cortina formada por um filme fino antes de molhar o substrato em movimento. Um dos limites mais importantes do processo é a ruptura da cortina, que define um limite inferior para a vazão do líquido de revestimento. Consequentemente, este limite inferior da vazão define a espessura mínima viável do filme depositado. Evidências experimentais mostraram que o uso de uma cortina compostas por duas camadas, com uma das camadas sendo mais fina e viscoelástica, pode atrasar a ruptura da cortina para taxas de fluxo mais baixas. A quebra de filmes líquidos de duas camadas, compostas por um líquido newtoniano e um viscoelástico, é estudado por meio da resolução das equações diferenciais que descrevem a evolução da configuração do filme até seu rompimento. O efeito de diferentes parâmetros no tempo de ruptura é determinado. Os resultados mostram o mesmo comportamento observado experimentalmente, a fina camada de líquido viscoelástico retarda o rompimento, estabilizando o filme líquido. / [en] Thin liquid sheets are present in a variety of systems and applications. Here, we are interested in double-layered sheets, which are common in the curtain coating process. In curtain coating, the liquid falls from a die forming a thin curtain before wetting the moving substrate. One of the most important process limits is the curtain breakup, which sets a lower limit for the coating liquid flow rate. Consequently, this flow rate lower limit defines the feasible minimum deposited film thickness. Experimental evidence have shown that using a two-layer curtain, with a viscoelastic thin layer, may delay the curtain breakup to lower flow ratios. The breakup of two-layer liquid sheets, composed of a Newtonian and a viscoelastic liquid, is studied by solving the differential equations that describe the evolution of the liquid sheet configuration until breakup. The effect of different parameters on the breakup time is determined. The results show the same behavior observed experimentally, thin viscoelastic liquid layer delays the breakup, stabilizing the liquid sheet.
82

Treize Etudes Pour L'Orchestre

Constantinidis, MariaSilvia Castillo 01 January 2008 (has links)
Treize Etudes Pour L?Orchestre is a thirteen-movement symphonic work for full contemporary orchestra. The purpose of this work has been to develop a sonic exploration of textural possibilities through the orchestral medium. The motivic materials of the whole piece were first utilized in pieces for one piano, piano and cello and two pianos combinations These smaller pieces ahs been included in the appendix section of this work. The orchestral work does not represent an orchestration of the smaller pieces, but an expansion of the material into different textural studies. Preparation for this work includes the study of twelve different bird sounds, first recorded and later musically transcribed to create thematic materials and secondary materials for this work; the study of production of fabric of sounds representing color spectrums and intensity through sound tapestries, and the sonic representation of water, a starry dark night and the jungle. The Treize Etudes Pour L?Orchestre is formally a through-composed work. The different musical materials created as motive unity of the whole work have been developed throughout it by means of using a variety of compositional devices and techniques including Schoenberg?s Klangfarbenmelodie, Messiaen?s ?Language Musicale?, Ives? quadraphonic effect, and Samuel Adler?s sound curtain technique, and, the use of folk-like materials; all within the parameters of acoustic instrumentation.
83

Modélisation des écoulements d’air et des transferts de chaleur dans un camion frigorifique : Etude des performances d’un dispositif de rideau d’air innovant pour le maintien de la chaîne du froid et la réduction des pertes à l’ouverture des portes / Modeling of airflow, heat and mass transfers in a refrigerated truck : Study of an innovative air curtain device to protect the cold chain and to reduce energy losses at the door opening

Lafaye de Micheaux, Téo 09 June 2016 (has links)
La préservation de la chaîne du froid est un paramètre particulièrement important dans le cadre de la distribution urbaine, où les fréquentes ouvertures de portes induisent une charge thermique d’infiltration. Afin de réduire les transferts de masse et de chaleur et de protéger l’ouverture, des rideaux d’air ont récemment été installés au niveau de l’ouverture des camions frigorifiques. L’objet de la présente étude est d’étudier ce type confinement. Deux modèles CFD ont été développés pour simuler les champs de températures et de vitesses dans un camion réfrigéré clos. Ils ont permis de montrer que la variation de la vitesse de soufflage ne modifie pas de manière significative la structure des écoulements. Différents conduits d’air sont modélisés. Les résultats numériques montrent que la configuration avec un conduit ouvert améliore fortement le renouvellement d’air. Puis, une étude numérique est réalisée dans le but d’étudier les infiltrations de chaleur et de masse au cours de l’ouverture des portes. Ces écoulements sont bien prédits par le modèle CFD, excepté à la transition entre les deux régimes d’infiltration. Une caisse expérimentale a été équipée d’un dispositif de rideau d’air composé d’un jet ambiant, d’un jet froid ou d’un jet double. En parallèle, un modèle numérique CFD a été développé pour étudier l’influence de différents paramètres. Une bonne concordance entre les résultats numériques et expérimentaux a été observée. L’efficacité du rideau d’air ambiant est maximale lorsque le point d’impact du rideau se situe dans le plan de l’ouverture. Le rideau double maintient efficacement l’homogénéité de la température pour de courtes ouvertures. Le rideau d’air froid est la meilleur configuration, il limite fortement l’augmentation de température de l’enceinte et permet des gains énergétiques importants. / Cold chain safety is a key parameter for urban distribution where the frequent door-opening induces a heat infiltration. In order to reduce heat and mass transfer, air curtain have recently been installed to protect the doorway of refrigerated truck. The aim of this work is to study this type of door insulation. Two CFD numerical models were developed to simulate the temperature and velocity fields in a closed refrigerated truck. These models showed that modifying the blowing velocity does not modify the air flow structure inside the cavity. Different air chutes were modelled. Numerical results demonstrate that the configuration with a convergent and an open duct strongly improves the air renewal. A numerical investigation was performed in order to study heat and mass infiltration rates during the opening. The infiltration flow rate is well predicted by the CFD model, except at the transition between both flow regimes. An experimental truck was equipped with an air curtain setup, composed by an ambient air jet, a cold air jet or a double jet. In parallel, a numerical CFD model was developed to study the influence of various parameters. Experimental and numerical results were found to be in good agreement. The maximum efficiency of the ambient air curtain is reached when the impact point of the jet occurs in the door plane at the ground level. This configuration is only relevant for short opening times. The double air curtain efficiently maintains the temperature homogeneity for short openings. The cold air curtain is the best configuration which strongly limits the temperature increase during the opening and allows important energy savings.
84

Nové brněnské hlavní nádraží a jeho veřejná prostranství / Brno New Train Station and its Public Spaces

Sedláček, Jakub January 2020 (has links)
The topic of the Diploma thesis is a design of the New train station in Brno. The plot is located on the boundary of three city districts – Komárov, Štýřice and Trnitá. This area includes the railway structure for the new train station and also its public spaces, which are very close to the river Svratka. The railway structure is designed as bridge construction, that rises all platforms and rail tracks to 7,65 metres above the ground level. So all of the railways do not become a barrier in the city. The main concept extends a longitudinal axis of the city boulevard through the train station, which creates a high-rise building in the southern part of the plot. This axis is written not only to the layout but also to the roof design. The train station includes two underground levels, ground floor and first floor. Underground levels consist of P+R parking, deliveries only area, technical facilities and subway terminal. The ground floor is the main traffic centre. There is an entrance hall, shopping area, bus terminal and public corridors. The first floor includes platforms for train departures and arrivals. There are also public spaces in the entrance hall. The basic structural system consists of two parts. The first part is a massive reinforced concrete structure of the railway bridge deck and all underground levels. This structure is based on reinforced concrete foundation pads with drilled piles. The second part is a steel frame structure of the roof. That includes steel columns and truss girders for the structure of the lower area. The higher part of the roof is designed as a steel-truss bridge with the characteristic profile. The new train station supposes to create a new gate to the city of Brno, that connects contemporary districts with the historical city center.
85

Nové brněnské hlavní nádraží a jeho veřejná prostranství / Brno New Train Station and its Public Spaces

Velfl, Martin January 2020 (has links)
The topic discussed in Brno for several decades is certainly the building of the new main railway station and its location. Countless architectural and urban studies have been done especially in 2018, which examined three possible locations of the station. After considering the possibilities, it was decided to place a new railway station near by the Svratka river. The advantage of the chosen location is the possibility of constructing a high-speed track, which is not possible in the current position of the station. Furthermore, this area allows the construction of a station on a green field, without limiting train traffic during the works. The capacity of the new designed train station represents an increase of 30-40 thousand passengers per day. Total capacity is approximately 100,000 passengers per day. However, construction activity in the area is limited by the flood risk factor. It is an effort to eliminate this risk with elements inspired by nature. These solutions include for example widening profle of the river , determining floodplains in such a way as to maintain access to the river. The diploma thesis offers a possible view of the architectural solution of the new railway station and its public spaces. The entrance hall of the station is located at one end of the visual axis, which is represented by the considered boulevard. The dominant building on the opposite side is the Cathedral of St. Peter and Paul. The requirements and location of the new main station mean an assumption for the creation of a new city icon. The iconic vaulted structure, which runs across the railway bridge, refers to the former glory and fame of the city. The curve of catenary arch used in the profile of vault is a symbol for the new station. The new station represents a significant impulse not only for the development of Brno, but especially for the development of new South district. The construction of the trade fairs complex a hundred years ago had a similer effect.
86

Nové brněnské hlavní nádraží a jeho veřejná prostranství / Brno New Train Station and its Public Spaces

Zrníková, Kamila January 2020 (has links)
The subject of proposal is a new dominant of the city of Brno. It is a building which will affect panorama of the city, a building which will be important part of a new South district and a new Brno Railway Station. The building will become orientation point in long-distance views as well as in the area. The proposal works with a building which is open and alive thanks to mix-use and public access on different height levels. Greenery forms the corner of the building and creates it’s identity. The base for architectural study became urban concept designed as a pre-diploma project. Important element of the concept is axis which draws the greenery from the river Svratka into the area and connects it with the new station. The Europoint – proposed building – becomes termination of the axis. The building is situated on a unique site which requires unique concept. The motive of the house is greenery and future vision of buildings which enrich surroundings in some ways. The basic volume is triangular and uses area of the site on maximum level with corner towards boulevard. This corner becomes the central element, especially from entry and view from the boulevard. I recreated the corner using vegetation into green and living. The green corner gives a new perspective on creating exposed corners, adds value to the urban area and creates identity of the building. The green motive intertwines with the building from entrance hall up to the bar at the highest floor. The volume of the building is defined by the inside usage and then form follows function. When choosing the functions I took into account needs of the area and took advantage of high-rise building. Commercial areas in the ground floor, administration centre of Czech Railways and conference rooms were created. The administrative use is added by co-working in the middle if the building, the upper part offers flats with view over Brno and in the crown is the highest placed bar in Brno.
87

Administrativní budova / Office Building

Světlík, Adam Unknown Date (has links)
The subject of diploma thesis is the elaboration of project documentation of an office building in the northern part of the city of Brno-Medlánky. The office building is designed as a four-storey, without basement. The roofs are flat, and the facade is designed as a glazed curtain wall. The operation of the office building is divided into an administrative part, a commercial part and a cafe. The individual operations do not intersect. Next to the building is a parking lot for customers and employees. The structural system of the building is RC frame with reinforced concrete walls. The internal walls are made of aerated concrete and acoustic lime-sand blocks. The partitions are precast plasterboard. The ceilings are cast-in-place reinforced concrete slabs. The floors are heavy floating with hot water underfloor heating. Most of the flat roofs are green. The drawing part was processed in Revit and AutoCAD.
88

Bytový dům / Residential Building

Štěpánková, Věra January 2013 (has links)
The project addresses the design documentation of a residential building. It is a detached house. The building has one basement and three floors. Residential house is a basement with a flat roof. The structural system consists of reinforced concrete columns and reinforced concrete ceiling. Perimeter and interior masonry infill masonry infill is composed of blocks YTONG. The roof is a single casing. The construction is based on the foundation footings and passports.
89

Administrativní budova Brno-Bystrc / Office building Brno-Bystrc

Dokulil, Martin January 2014 (has links)
The master´s thesis deals with a project documentation of a office building with fitness center in Brno-Bystrc. The object is designed as a detached building with four floors and with one basement. Floor plan of the building is regular, staffed by sloping terrain. In basement is situated underground garage and technical rooms of building. In the first floor is fitness center and garage for a customers. In other floors are office spaces for private company. Above the roof is a engine rooms of ventilation. The structural system is reinforced concrete skeleton, facade is designed as a curtain walling. The object is covered with a flat roof.
90

Autosalon se servisem / Car dealership with auto repair shop

Wilkonský, Roman January 2015 (has links)
This diploma thesis is being solved for documentation of building in the stage of execution. The building is designed as a showroom with car repair shop. The building site is located in the land registry of Ostrava – Vítkovice. Project documentation is designed accordingly to the valid Czech Republic’s laws, bills and building standards. The building is divided into two objects the first one is showroom with administration and the second one is the car repair shop with washing room and restrooms. These two objects are structurally and operationally connected. The largest plan dimensions are 68,56 x 38,36 m. The building is designed as a reinforced concrete frame in the administrative part and a reinforced concrete wall system in the car repair part. The roof is in both cases realized by using steel trusses. The reinforced concrete frame is lined with aerated concrete masonry. In the roof part it is cladded with sandwich steel panels. The building is founded on reinforced concrete foundation pads with combination of strip foundations. The car repair shop is designed as one floor building, whereas the administrative part is designed as two floor.

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