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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

Strength and Performance of Steel Fiber Reinforced Concrete Post-Tensioned Flat Plates

Rosenthal, Joshua Thomas 06 August 2019 (has links)
Load testing was performed on a one-third scale model steel fiber reinforced concrete post-tensioned flat plate. The specimen had nine 10ft x 10ft x 3in. bays along with a 2ft-6in. overhang. Distributed loading was applied with a whiffle tree loading system at each bay and overhang section. Throughout the test, crack widths, crack locations, deflections, concrete strains, and reinforcing bar strains were monitored. The post-tensioned flat plate was designed to just meet the maximum allowable stress requirements of ACI 318. Minimal quantities of hairline cracks were observed after stressing the slab, and up through service-level loads, the cracks grew slightly in length and width. The slab behaved elastically through service-level loading. As factored-level loading was approached, the slab began to behave inelastically as indicated by both the load-deflection plots and the load-strain plots. A total ultimate load of 282psf (174psf of applied load) was reached when concrete crushing occurred. A 0.20in. wide full-length crack was observed running on the bottom surface of the slab between column lines 1 and 2, and a full-length crack was observed at column line 2 on the top surface of the slab. These two cracks were the leading contributors to the slab's failure. The performance of the SFRC post-tensioned flat plate indicated that considerations should be made to remove requirements for negative moment reinforcement in post-tensioned flat plates when SFRC is used. Also, the requirements for positive moment reinforcement should be modified. Additionally, the SFRC post-tensioned flat plate exhibited excellent levels of ductility. More experimentation should be conducted to determine if the maximum tensile stress in ACI 318 can be increased for post-tensioned flat plates with SFRC. / Master of Science / Load testing was performed on a one-third scale model steel fiber reinforced concrete (SFRC) post-tensioned flat plate. Post-tensioned flat plates are a type of concrete structural system typically used as flooring. This system typically employs high-strength steel strands, which are stretched to introduce compression into the concrete, which helps prevent the onset of cracking. The specimen had nine 10ft x 10ft x 3in. bays along with a 2ft-6in. overhang. Distributed loading was applied with a whiffle tree loading system at each bay and overhang section. The whiffle tree loading system was used to allow actuators to spread out the vertical loading on the slab. During the test, crack widths, crack locations, deflections, concrete strains, and reinforcing bar strains were monitored. The post-tensioned flat plate was designed to just meet the maximum allowable stress requirements of the governing standard, ACI 318. Minimal quantities of hairline cracks were observed after stressing the slab, and up through service-level loads, the cracks grew slightly in length and width. As larger loads were applied, the cracks grew and the effects of these cracks on the slab were evidenced in the deflection and strain measurements. A total ultimate load of 282psf (174psf of applied load) was reached when concrete crushing occurred. A 0.20in. wide full-length crack was observed running on the bottom surface of the slab between column lines 1 and 2, and a full-length crack was observed at column line 2 on the top surface of the slab. These two cracks were a driving force in the slab’s failure. The performance of the SFRC post-tensioned flat plate indicated that considerations should be made to change the requirements for negative and positive moment reinforcement in post-tensioned flat plates when SFRC is used. Additionally, the SFRC post-tensioned flat plate exhibited great performance after significant cracking was present. More experimentation should be conducted to determine if the maximum allowable tensile stress in ACI 318 can be increased for post-tensioned flat plates with SFRC.
42

Práva a povinnosti člena společenství vlastníků jednotek / Rights and duties of a member of the association of owners of (residential) units

Šebesta, David January 2012 (has links)
Rights and duties of the member of Flat owners association The purpose of my thesis is to focus on applicable law in the Czech Republic, particularly the Flat Ownership Act 72/1994 Coll. and analyze the rights and duties of the members of Unit owners association. The reason for my research is that the flat ownership and housing is one of the most important sector which affects the general public. The thesis is composed of three chapters, each of them dealing with aspects of flat ownership. Chapter one informs about historical context of housing and tries to introduce the flat ownership in general. Thesis provides information about contemporary regulation and also about relevant provisions of new coming civil code which will be applicable by 1 January 2014. Next chapter is introductory to Flat owners association and defines basic terminology. It explains a legal framework regulating the legal entity of the association and regulation of common property management. Including the internal structure and describes some relevant issues in respect with Flat owners association. Last chapter is most significant part of the thesis. The main aim is to analyze the rights and duties of flat owners and especially the members of flat owners association. The thesis concentrates on problems resulting from this...
43

IMRT and Rotational IMRT (mARC) Using Flat and Unflat Photon Beams

Sheta, Amal 16 August 2016 (has links) (PDF)
For more than 50 years attening filters have been inserted into the beam path oflinacs to produce a uniform energy fluence distribution of the photon beam and make it suitable for clinical use. Recently, linacs without flattening fifilter (Flattening FilterFree - FFF) are increasingly used in radiotherapy because of its benefifits, e.g. high dose rate (2000 MU/min), reduced scattered and leakage radiation. Hypofractionated radiotherapy is interested in the high dose rate of FFF beams to shorten the treatment delivery time (TDT) especially the FFF beams have acceptable flatness at small fifieldsizes. Radiotherapy techniques that deliver intensity-modulated beams (IMBs), e.g.Tomotherapy, intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT), deal with the non-uniformity of the FFF beam profifile and produce homogeneous dose to the target as FF beams do. Siemens modified the Artiste linac in order to enable photon beam delivery with and without a flattening fifilter. The VMAT version developed by Siemens for Artiste linacs as a novel radiation technique is a modulated arc therapy (mARC). mARC technique is available with single, double and multiple complete or partial arcs. The aims of the current study were the determination of the main characteristics of 7 MV and 11 MV FFF photon beams in comparison with their corresponding 6 MV and 10 MV FF photon beams from Artiste digital linacs. Furthermore, IMRT planning comparisons using FF and FFF photon beams were performed using an Oncentra planning system. The performance of various mARC techniques were estimated and compared with Step and Shoot (S&S) IMRT by using a RayStation planning system. The mARC plans created by FF and FFF beams were evaluated to know which technique is the best. All the treatment plans were created for simple and complex shaped target volumes. The treatment plans are compared using two parameters - plan quality and treatment effi ciency. In addition to the planning study, the plan quality assurance of IMRT and mARC plans were performed using two difffferent volumetric quality assurance devices, Delta4 and Octavius 4D. Removal of the flattening fifilter causes changes in the dosimetric features of photon beams. IMRT plans with and without flattening fifilter were clinically acceptable where both plans have similar quality. In comparison with IMRT-FF, IMRT-FFF plansrequire more MUs and for some clinical cases require longer TDT. mARC technique can deliver dose distributions that are comparable to S&S-IMRT and could be an alternative with a potential to improve the effi ciency of the IMRT treatment delivery.
44

Development of a Flat Panel Detector with Avalanche Gain for Interventional Radiology

Wronski, Maciej 03 March 2010 (has links)
A number of interventional procedures such as cardiac catheterization, angiography and the deployment of endovascular devices are routinely performed using x-ray fluoroscopy. To minimize the patient’s exposure to ionizing radiation, each fluoroscopic image is acquired using a very low x-ray exposure (~ 1 uR at the detector). At such an exposure, most semiconductor-based digital flat panel detectors (FPD) are not x-ray quantum noise limited (QNL) due to the presence of electronic noise which substantially degrades their imaging performance. The goal of this thesis was to investigate how a FPD based on amorphous selenium (a-Se) with internal avalanche multiplication gain could be used for QNL fluoroscopic imaging at the lowest clinical exposures while satisfying all of the requirements of a FPD for interventional radiology. Towards this end, it was first determined whether a-Se can reliably provide avalanche multiplication gain in the solid-state. An experimental method was developed which enabled the application of sufficiently large electric field strengths across the a-Se. This method resulted in avalanche gains as high as 10000 at an applied field of 105 V/um using optical excitation. This was the first time such high avalanche gains have been reported in a solid-state detector based on an amorphous material. Secondly, it was investigated how the solid-state a-Se avalanche detector could be used to image X-rays at diagnostic radiographic energies (~ 75 kVp). A dual-layered direct-conversion FPD architecture was proposed. It consisted of an x-ray drift region and a charge avalanche multiplication region and was found to eliminate depth-dependent gain fluctuation noise. It was shown that electric field strength non-uniformities in the a-Se do not degrade the detective quantum efficiency (DQE). Lastly, it was determined whether the solid-state a-Se avalanche detector satisfies all of the requirements of interventional radiology. Experimental results have shown that the total noise produced by the detector is negligible and that QNL operation at the lowest fluoroscopic exposures is indeed possible without any adverse effects occurring at much larger radiographic exposures. In conclusion, no fundamental obstacles were found preventing the use of avalanche a-Se in next-generation solid-state QNL FPDs for use in interventional radiology.
45

Development of a Flat Panel Detector with Avalanche Gain for Interventional Radiology

Wronski, Maciej 03 March 2010 (has links)
A number of interventional procedures such as cardiac catheterization, angiography and the deployment of endovascular devices are routinely performed using x-ray fluoroscopy. To minimize the patient’s exposure to ionizing radiation, each fluoroscopic image is acquired using a very low x-ray exposure (~ 1 uR at the detector). At such an exposure, most semiconductor-based digital flat panel detectors (FPD) are not x-ray quantum noise limited (QNL) due to the presence of electronic noise which substantially degrades their imaging performance. The goal of this thesis was to investigate how a FPD based on amorphous selenium (a-Se) with internal avalanche multiplication gain could be used for QNL fluoroscopic imaging at the lowest clinical exposures while satisfying all of the requirements of a FPD for interventional radiology. Towards this end, it was first determined whether a-Se can reliably provide avalanche multiplication gain in the solid-state. An experimental method was developed which enabled the application of sufficiently large electric field strengths across the a-Se. This method resulted in avalanche gains as high as 10000 at an applied field of 105 V/um using optical excitation. This was the first time such high avalanche gains have been reported in a solid-state detector based on an amorphous material. Secondly, it was investigated how the solid-state a-Se avalanche detector could be used to image X-rays at diagnostic radiographic energies (~ 75 kVp). A dual-layered direct-conversion FPD architecture was proposed. It consisted of an x-ray drift region and a charge avalanche multiplication region and was found to eliminate depth-dependent gain fluctuation noise. It was shown that electric field strength non-uniformities in the a-Se do not degrade the detective quantum efficiency (DQE). Lastly, it was determined whether the solid-state a-Se avalanche detector satisfies all of the requirements of interventional radiology. Experimental results have shown that the total noise produced by the detector is negligible and that QNL operation at the lowest fluoroscopic exposures is indeed possible without any adverse effects occurring at much larger radiographic exposures. In conclusion, no fundamental obstacles were found preventing the use of avalanche a-Se in next-generation solid-state QNL FPDs for use in interventional radiology.
46

Městský polyfunkční dům na ulici Křížová, Brno / Multipurpose Town House on Křížová Street, Brno

Jakůbková, Magdalena January 2011 (has links)
The project deals with the development of a gap site which forms the front line of a street in a city block. The building consists of two parts: in the southern corner a five-storey administrative building with a café and a patio is situated; the second, larger part is a block of flats with a commercial parterre connected with a pedestrain zone. The block of flats is – in accordance with the surrounding built-up area – designed as a house with access galleries, the majority of flats contain two storeys. Parking spaces are provided in the form of two underground storeys accessible from the inner block.
47

Retracing the Journey of Franz Schubert’s Wanderer: Musical Fingerprints in the B-flat Sonata, D. 960

Roggero, Amanda Marie 01 July 2004 (has links)
No description available.
48

Městský dům - architektura kombinace funkcí / City House – Mixet Use Architecture

Salva, Martin January 2013 (has links)
The project deals with completion a REC block buildings in Brno – Zábrdovice, defined by local roads. For the design of mass was used a porosity principle, when the site was covered with maximum static mass cutted by dynymic communication-optimal connections through the object. Object has five floors and a basement with garages and technical facilities. In the 1st floor and the part of 2nd floor are business premises, on the 2nd and 3rd level are administrative premises. On the part of a 3rd floor and in 4NP and 5th floor there are apartments. The foundations of an object is the reinforced concrete slab, the constuction systém is formed by reinforced-concrete columns with brick walls. Ceilings and staircases are monolithic reinforced concrete. Object is topped by a flat roof, part of the roof is greened.
49

Nájemné bytu a faktory, které je ovlivňují ve městě Prostějov. / Apartment rent and the factors that influence it in the city of Prostějov

Novák, Tomáš January 2015 (has links)
This thesis is focused on the analysis and comparison of rental apartments in Prostejov and all the factors that have the level of rents in the area of influence. The work presents textual and graphical part of a designated location according to the amount of rent in various parts of the city Prostejov flats of sizes 1 + 1, 1 + KK, 2 + 1, 2 + KK, 3 + 1, 3 + KK. These dispositions are examined and appreciation is shown in tables and graphs. The result is a calculation and comparison of individual dispositions rent flats and assess the factors that have influence on the price.
50

Cobertura das folhas de soja utilizando diferentes pontas de pulverização /

Moniz, Arianne January 2020 (has links)
Orientador: Ulisses Rocha Antuniassi / Resumo: Para uma aplicação de pesticidas com qualidade e segurança, é necessário a escolha adequada da ponta de pulverização, espectro de gotas e volume de calda. O objetivo dessa pesquisa foi avaliar a interação entre os formatos dos jatos de pulverização, com espectro de gotas similares e volumes de calda na cobertura nas folhas de soja. A pesquisa foi realizada na Faculdade de Ciências Agronômicas – UNESP/Botucatu e na Fazenda Fiorelli, Tejupá/SP. Para verificar se as pontas de pulverização utilizadas no ensaio possuíam o espectro de gotas similares, foi realizado um pré-ensaio, através da análise do espectro de gotas no analisador de partículas por imagem e em tempo real VisiSize Portable (Oxford Lasers Ltd/UK). A avaliação de cobertura das folhas foi conduzida em dois esquemas fatoriais 3x2, sendo um esquema fatorial utilizando as folhas do extrato superior da planta e outro no extrato médio/inferior e o delineamento em blocos casualisados, com cinco repetições. Os tratamentos foram compostos por três pontas de pulverização com formato do jato plano, jato plano duplo e jato plano angulado e dois volumes de caldas (100 e 200 L ha-1), na pressão de trabalho de 200 kPa. As caldas de pulverização foram preparadas utilizando o fungicida Sphere Max®, Aureo® e o corante Luxcor LRM 100. Para a avaliação da cobertura das folhas foram realizadas as aplicações no estádio R1 da soja, utilizando o pulverizador Columbia AD18, com velocidade de deslocamento de 7,8 e 3,9 km h-1 para os volumes ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: For a pesticide application with quality and safety, it is necessary to choose the correctly spray nozzle, droplet spectrum and volume of spray solution. The aim of this research was to evaluate interaction between the spray nozzles shaped, with a similar droplet spectrum and volume of spray solution in the coverage in soybean leaves. The research was perform in the Faculdade de Ciências Agronômicas - UNESP/Botucatu and at Fazenda Fiorelli, Tejupá/SP. To verify if the nozzles used in the experiment had a similar droplet spectrum was carry out a pre-test, through the analysis of the droplet spectrum using the VisiSize Portable real-time particle analyzer. The evaluation of leaves coverage was conducted in two 3x2 factorial schemes, one factorial scheme using the leaves of the upper portion of a plant canopy and another in the medium/lower portion of a plant canopy and was use randomized block design, with five replications. The treatments consisted of three spray nozzles with different shaped: pre-orifice low drift flat fan, pre-orifice low drift double flat fan and angled flat fan and two volume of spray solution (100 and 200 L ha-1), at a working pressure of 200 kPa. The spray solutions were prepared using the mixture with Sphere Max® fungicide, Aureo® and Luxcor LRM 100 dye. For the evaluation of the leaves coverage, the applications were perform at the soybean R1 stage, using the Columbia AD18 sprayer, with the spray velocity of 7.8 and 3.9 km h-1 for the volume of spray s... (Complete abstract click electronic access below) / Mestre

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