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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.
11

DETERMINATION OF KNOWN EXHALATION VALVE LEAKAGE USING THE RESPIFIT <sup>TM</sup> IRRITANT SMOKE TEST KIT

SNYDER, ERIN MARIE 11 October 2001 (has links)
No description available.
12

Metodologia para estudo da caracterização estrutural de painéis de madeira laminada colada cruzada / Methodology for the study of structural characterization of wood panels of cross laminated timber (CLT)

Pereira, Marcos Cesar de Moraes 30 January 2015 (has links)
O CLT (Cross Laminated Timber) ou MLCC (Madeira Laminada Colada Cruzada) é um painel compósito estrutural formado por lamelas de madeira unidas com adesivos próprios para uso estrutural, com as camadas montadas de maneira perpendicular à camada anterior. É utilizado como elemento estrutural principal em edificações térreas e multipavimentos por ter características estruturais semelhantes ao concreto armado. Os objetivos gerais deste trabalho foram desenvolver uma metodologia de ensaios para a caracterização estrutural de painéis de MLCC visando a contribuição para a normatização do produto no Brasil e o estudo da rigidez de um painel modelo. Foi fabricado um painel com dimensões estruturais utilizando madeira de Pinus elliotti e adesivo estrutural à base de melamina-ureia formaldeído. Os ensaios mecânicos realizados foram adequados para caracterização estrutural de painéis de MLCC e podem compor uma futura normatização. Os valores de rigidez para o painel avaliado apresentaram módulo de elasticidade abaixo dos especificados pela norma americana ANSI/APA PGR 320 e pela especificação técnica europeia ETA06/0138, porém os módulos de rigidez do rolling shear e de compressão obtiveram valores similares aos recomendados. / The CLT (Cross Laminated Timber) is a structural composite panel formed by wooden slats together with own stickers for structural use, with the layers mounted perpendicular to the previous layer. It is used as the main structural element in single-story buildings with one or more floors for having structural features similar to reinforced concrete. The aims of this study were to develop a test methodology for structural characterization of MLCC panels aimed at contributing to the standardization of the product in Brazil and the study of rigidity of a panel model. A panel with structural dimensions using wood of Pinus elliotti and structural adhesive melamine urea formaldehyde base was manufactured. The mechanical tests were suitable for structural characterization of MLCC panels and can compose a future standardization. The stiffness values reported for the modulus of elasticity panel presented below specified by the US standard ANSI/APA PGR 320 and the European Technical Specification ETA06/0138, but the stiffness of the rolling shear and compression modules obtained similar to recommended values.
13

Product Requirements for Fabric Sofa Covers in Accordance with Customer Life Situation at Home

Yusuf Kocer, Ahmet, Mahmood Zubair, Muhammad January 2010 (has links)
IKEA is a unique home furnishing retailer in selling water washable slip covers for living room sofa.The aim of this research is to set product requirements for sofa covers in accordance with the usage at home by customers.This was done by conducting consumer survey to understand need, reviewing existing quality, test methods and proposal of new requirements and test methods. The overall objective is every day quality guarantee and better communication with customers in store. / Program: Magisterutbildning i Applied Textile Management
14

Utilização de métodos não destrutivos e semi destrutivos na avaliação de pontes de concreto. / Use of non-destructive methods and semi-destructive evaluation of concrete bridges.

Choquepuma Sahuinco, Melquiades Hermógenes 12 August 2011 (has links)
As estruturas de concreto, especialmente as pontes de concreto, estão sujeitas a um conjunto de ações que leva ao seu envelhecimento devido aos processos de deterioração, muitas vezes deixando de responder às exigências para as quais foram projetadas. Tal situação, em muitos casos, é agravada pela falta de conhecimento dos processos e mecanismos de degradação assim como o uso de técnicas tradicionais para inspeção de estruturas, estas muitas vezes se mostram limitadas quando são aplicadas isoladamente. Este trabalho mostra uma comparação entre a inspeção visual (usada há décadas) e a aplicação de métodos de ensaios não destrutivos e semi-destrutivos na avaliação da condição estrutural atual de pontes. Enquanto a inspeção visual mostra uma condição qualitativa, os métodos de ensaios não destrutivos são quantitativos e apresentam o potencial de determinar os danos no interior da estrutura que não são visíveis a olho nu. Portanto, visando alertar para o problema da degradação das pontes, busca-se integrar a inspeção visual com a avaliação através do uso de métodos de ensaio. Assim, neste trabalho é feito um estudo de caso da ponte sobre o rio Jaguari. Este estudo visa determinar a condição atual da estrutura através de ensaios não destrutivos e semi-destrutivos, estabelecendo uma correlação entre os resultados destes ensaios e a avaliação da inspeção visual. Dessa forma, procura-se apresentar uma alternativa na avaliação de pontes de concreto. / Concrete structures, particularly concrete bridges, are subjected to a set of actions that leads to aging due to the processes of deterioration, and many times these structures do not respond to the demands for which they have been designed. This situation, in many cases, is exacerbated by lack of knowledge of processes and mechanisms of degradation and by the use of traditional techniques for inspection of structures, these techniques are limited when applied alone. This work shows a comparison between the visual inspection (used for decades) and the application of nondestructive testing methods and semi-destructive on the evaluation of current structural condition of bridges. While visual inspection shows a qualitative condition, the methods of nondestructive testing are quantitative and have the potential to determine the damage inside the structure that are not visible with a simple view. Therefore, in order to draw attention to the problem of deterioration of bridges, we seek to integrate the visual inspection with the assessment through the use of test methods. Thus, in this work a case study of the bridge about the river Jaguari is done. This study aims at determining the current condition of the structure through nondestructive and semi-destructive methods, establishing a correlation between the results of these tests and the evaluation of visual inspection. We seek to present an alternative in the assessment of concrete bridges.
15

Methods for Testing Concurrent Software

Radnoci, Ramon January 2009 (has links)
<p> </p><p>Most software today is concurrent and are used in everything from cell-</p><p>phones, washing machines, cars to aircraft control systems. The reliability</p><p>of the concurrent software may be more or less critical, depending on which</p><p>a.o. domain it is functioning in. Irrespective of domain, the concurrent</p><p>software must be sufficiently reliable.</p><p>It is therefore interesting to study how adaptable test methods for sequential</p><p>software are to test concurrent software. Novel test methods for concurrent</p><p>software can be developed by adapting test methods for sequential software.</p><p>In this dissertation, adaptability factors have been identified by conducting</p><p>a literature survey over state-of-the-art test methods. Directions taken in</p><p>the research of concurrent software testing is described by the survey. The</p><p>survey also demonstrates differences and similarities between test methods.</p><p>Three research contributions has been achieved by this dissertation. First,</p><p>this dissertation presents a survey over state-of-the-art-test methods. The</p><p>second contribution is the identified adaptability factors that should be</p><p>added to a test method for sequential software, that will be adapted to test</p><p>concurrent software. Finally, the third contribution to the field of concurrent</p><p>software testing is the identified future work in areas where test methods for</p><p>concurrent software has not been researched much or at all.</p><p> </p>
16

Developing and Evaluating Rapid Test Methods for Measuring the Sulphate Penetration Resistance of Concrete in Relation to Chloride Penetration Resistance

Karkar, Ester 12 December 2011 (has links)
External sulphate attack on concrete can lead to cracking, expansion and sometimes loss of cohesiveness of hardened cement paste. Therefore, aside from using sulphate resistant cementitious binders, it is important to design concrete which can resist sulphate penetration. In this research, both ASTM C1202 and NT Build 492 electrical migration tests were modified such that sulphate rather than chloride penetration resistances were measured. Modifications included exposing concrete specimens to Na2SO4 rather than NaCl solutions and measuring the depth of sulphate penetration visually using BaCl2+KMnO4 rather than AgNO3 solution. Nine concrete mixtures of varying w/cm, slag replacement and cement types were tested in both original standard tests and modified tests to evaluate the influence of these material variables on test results and compare chloride to sulphate results. It was found that while migration coefficients and total charge passing were lower for sulphate, the influence of material variables were relatively similar.
17

Smoke off the water : determination of mass emission rates from off-gassing surfaces

Rutgers, Gordon W. P. 28 October 2013 (has links)
A flux chamber is an effective and recognized means of sampling off gassing surfaces, such as landfills and settling ponds. Because there has been little discussion on the survey patterns used for deploying flux chambers. This thesis looks into developing a scalable survey pattern as part of a flux chamber test methodology that can accurately give a representative sample of the emission components and the emission rate of the entire area of interest. The test methodology evolved out of literature review and experiences of two case studies which are discussed within this thesis.
18

Developing and Evaluating Rapid Test Methods for Measuring the Sulphate Penetration Resistance of Concrete in Relation to Chloride Penetration Resistance

Karkar, Ester 12 December 2011 (has links)
External sulphate attack on concrete can lead to cracking, expansion and sometimes loss of cohesiveness of hardened cement paste. Therefore, aside from using sulphate resistant cementitious binders, it is important to design concrete which can resist sulphate penetration. In this research, both ASTM C1202 and NT Build 492 electrical migration tests were modified such that sulphate rather than chloride penetration resistances were measured. Modifications included exposing concrete specimens to Na2SO4 rather than NaCl solutions and measuring the depth of sulphate penetration visually using BaCl2+KMnO4 rather than AgNO3 solution. Nine concrete mixtures of varying w/cm, slag replacement and cement types were tested in both original standard tests and modified tests to evaluate the influence of these material variables on test results and compare chloride to sulphate results. It was found that while migration coefficients and total charge passing were lower for sulphate, the influence of material variables were relatively similar.
19

Termisk cykling provuppställning konstruktion och provning av TBCs för dieselmotorapplikation / Thermal cycling test setup design and testing of TBCs for diesel engine application

Bhoje, Sourabh January 2017 (has links)
Thermal barrier coatings (TBCs) thermally insulate the substrate from high temperature exposure. This work attempted to simulate real engine thermal cyclic conditions by designing a test method to evaluate the thermal cyclic fatigue (TCF) performance of different coatings applied inside exhaust manifold of a diesel engine. The coatings investigated in this work comprised of two plasmas-sprayed TBCs (conventional 8YSZ and nanostructured 8YSZ) and one bond coat (NiCoCrAlY). Additionally, these coatings were exposed to isothermal testing and their oxidation behavior was evaluated.   All the coatings along with only substrate were exposed to temperature around 525°C for 150 cycles in thermal cyclic testing carried out on Scania’s heavy-duty diesel engine. For isothermal testing, all coatings along with only substrate material were exposed to 650°C and 750°C for 168 hours respectively. Microstructural analysis by SEM/EDS was carried out to compare the microstructural evolution of the tested coatings with the as sprayed TBCs. In the case of thermal cyclic test, all coatings showed no failure and no TGO growth up to 150 cycles. In the EDS analysis for isothermally tested coatings, oxidation of the substrate at bond coat- substrate interface instead of TGO growth was observed. Bond coat showed lowest oxide layer thickness at 650°C and 750°C followed by conventional YSZ and then nanostructured YSZ. But, conventional YSZ showed microcracks in top coat near top coat- bond coat interface after isothermal testing. Thermal cyclic and isothermal exposure test results showed that bond coated substrate and nanostructured YSZ have the potential to be implemented inside the real manifold.
20

Metodologia para estudo da caracterização estrutural de painéis de madeira laminada colada cruzada / Methodology for the study of structural characterization of wood panels of cross laminated timber (CLT)

Marcos Cesar de Moraes Pereira 30 January 2015 (has links)
O CLT (Cross Laminated Timber) ou MLCC (Madeira Laminada Colada Cruzada) é um painel compósito estrutural formado por lamelas de madeira unidas com adesivos próprios para uso estrutural, com as camadas montadas de maneira perpendicular à camada anterior. É utilizado como elemento estrutural principal em edificações térreas e multipavimentos por ter características estruturais semelhantes ao concreto armado. Os objetivos gerais deste trabalho foram desenvolver uma metodologia de ensaios para a caracterização estrutural de painéis de MLCC visando a contribuição para a normatização do produto no Brasil e o estudo da rigidez de um painel modelo. Foi fabricado um painel com dimensões estruturais utilizando madeira de Pinus elliotti e adesivo estrutural à base de melamina-ureia formaldeído. Os ensaios mecânicos realizados foram adequados para caracterização estrutural de painéis de MLCC e podem compor uma futura normatização. Os valores de rigidez para o painel avaliado apresentaram módulo de elasticidade abaixo dos especificados pela norma americana ANSI/APA PGR 320 e pela especificação técnica europeia ETA06/0138, porém os módulos de rigidez do rolling shear e de compressão obtiveram valores similares aos recomendados. / The CLT (Cross Laminated Timber) is a structural composite panel formed by wooden slats together with own stickers for structural use, with the layers mounted perpendicular to the previous layer. It is used as the main structural element in single-story buildings with one or more floors for having structural features similar to reinforced concrete. The aims of this study were to develop a test methodology for structural characterization of MLCC panels aimed at contributing to the standardization of the product in Brazil and the study of rigidity of a panel model. A panel with structural dimensions using wood of Pinus elliotti and structural adhesive melamine urea formaldehyde base was manufactured. The mechanical tests were suitable for structural characterization of MLCC panels and can compose a future standardization. The stiffness values reported for the modulus of elasticity panel presented below specified by the US standard ANSI/APA PGR 320 and the European Technical Specification ETA06/0138, but the stiffness of the rolling shear and compression modules obtained similar to recommended values.

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