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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.
71

Smoke Movement Analysis (Smoke Transport Within a Corridor)

Cummings, W. Mark 18 November 2004 (has links)
"A series of full-scale fire tests were performed, using a fire compartment and an adjoining long (30+ m) corridor, as part of an effort to quantify the dynamics associated with smoke transport within a corridor. The tests were performed at the U.S. Coast Guard Research and Development Center’s Fire and Safety Test Detachment in Mobile, Alabama on board the Test Vessel Mayo Lykes. The resulting empirical data was analyzed in an effort to develop a method that could be used to estimate the movement of smoke within a corridor. The objective is to potentially incorporate this method into a smoke movement analysis “tool” that could, in turn, be used in conjunction with a fire safety analysis methodology previously developed by the U.S. Coast Guard; the Ship fire Safety Engineering Methodology (SFSEM). The goal is to develop a smoke movement analysis “module” that can be utilized in conjunction with the SFSEM when conducting an overall fire safety analysis of a ship. Of particular interest is the speed at which the smoke propagates along the length of the corridor. The focus of a smoke movement module would be life safety. A conservative assumption is made that if smoke is present in sufficient quantities to fill a corridor, then the corridor is to be considered untenable and not available as a means of egress. No attempt is made to address toxicity or density issues associated with smoke. This analysis developed correlations for the corridor smoke velocity, both as a function of the heat release rate of the associated fire and the upper layer temperatures within the fire compartment. Problems associated with the data collection and the narrow range of fire sizes used had a detrimental impact on the confidence level in the correlation based on heat release rate. The data do appear to confirm the results of previous efforts that indicated a weak relationship between the heat release rate and smoke velocity, on the order of the one-third to one-fourth power. The temperature data tended to be less problematic. This correlation shows promise for potential use with both the SFSEM and other existing computer models/routines. However, unlike previous studies of this relationship, the results of these data suggest that the velocity-temperature relationship is linear and not a square-root function. The test data were compared to predictive results using the CORRIDOR routine within FPETOOL. In general, the CORRIDOR results provided a reasonable good correlation to the tests data. Both the wave depth and temperature loss within the wave, as a function of distance, were consistently over-predicted. The velocity results were mixed, but were generally within 20 percent of the test data. The results of this study show promise, with respect to developing a correlation that can be used a method for predicting smoke movement in a corridor. However, due to the questionable nature of some of the data estimates, coupled with both a lack of sufficient number of tests and a limited range of fire sizes used, additional test data will be required to further validate the accuracy and refine the correlation(s) suggested by this work."
72

Parameterization analysis and inversion for orthorhombic media

Masmoudi, Nabil 05 1900 (has links)
Accounting for azimuthal anisotropy is necessary for the processing and inversion of wide-azimuth and wide-aperture seismic data because wave speeds naturally depend on the wave propagation direction. Orthorhombic anisotropy is considered the most effective anisotropic model that approximates the azimuthal anisotropy we observe in seismic data. In the framework of full wave form inversion (FWI), the large number of parameters describing orthorhombic media exerts a considerable trade-off and increases the non-linearity of the inversion problem. Choosing a suitable parameterization for the model, and identifying which parameters in that parameterization could be well resolved, are essential to a successful inversion. In this thesis, I derive the radiation patterns for different acoustic orthorhombic parameterization. Analyzing the angular dependence of the scattering of the parameters of different parameterizations starting with the conventionally used notation, I assess the potential trade-off between the parameters and the resolution in describing the data and inverting for the parameters. In order to build practical inversion strategies, I suggest new parameters (called deviation parameters) for a new parameterization style in orthorhombic media. The novel parameters denoted ∈d, ƞd and δd are dimensionless and represent a measure of deviation between the vertical planes in orthorhombic anisotropy. The main feature of the deviation parameters consists of keeping the scattering of the vertical transversely isotropic (VTI) parameters stationary with azimuth. Using these scattering features, we can condition FWI to invert for the parameters which the data are sensitive to, at different stages, scales, and locations in the model. With this parameterization, the data are mainly sensitive to the scattering of 3 parameters (out of six that describe an acoustic orthorhombic medium): the horizontal velocity in the x1 direction, ∈1 which provides scattering mainly near the zero offset in the x1-x3 vertical plane, and ∈d, which is the ratio of the horizontal velocity squared in the x1 and x2 direction. Since, with this parameterization, the radiation pattern for the horizontal velocity is azimuth independent, we can perform an initial VTI inversion for two parameters (velocity and ∈1), then use ∈d to fit the azimuth variation in the data. This can be done at the reservoir level or any region of the model.
73

Endommagement localisé dans les roches tendres. Expérimentation par mesure de champs / Localized damage in soft rock : experiments with field measurement techniques

Nguyen, Tuong Lam 23 February 2011 (has links)
Le travail de recherche que nous présentons dans cette thèse concerne, tout d'abord, une étude expérimentale sur le processus de fissuration sous compression uniaxiale d'échantillons de roche ayant des entailles rectilignes inclinées. Ensuite, nous présentons une étude de l'évolution de la localisation des déformations vers la rupture dans des échantillons ayant une géométrie particulière à encoches arrondies ; cette géométrie (inspirée par les travaux de Meuwissen et al. (1998) sur les métaux) favorise la localisation de la déformation de cisaillement en compression uniaxiale avant l'apparition de fissures. Notre étude expérimentale a été réalisée sur deux matériaux différents: une roche naturelle d'origine volcanique (le Tuf de Naples) et une « roche » artificielle (le CPIR09). Nous utilisons dans cette thèse une combinaison de trois techniques de mesure de champs : (i) la corrélation d'images numériques (Digital Image Correlation, DIC) pour les mesures des champs cinématiques à la surface d'échantillons; (ii) l'enregistrement d'Emissions Acoustiques (EA) et la localisation des sources des EA, qui permettent de suivre l'endommagement dans un échantillon au cours du chargement; (iii) la tomographie à Rayons-X, avant et après chaque essai, afin de caractériser les défauts et les discontinuités préexistants dans le volume des éprouvettes et de mieux comprendre la fissuration dans le volume. / The research presented in this thesis concerns, firstly, an experimental study on the process of fracture in uniaxial compression of rock samples containing narrow, rectilinear notches inclined with respect to the axis of loading. Secondly, we study the evolution of shear strain localisation towards fracturing and failure in specimens of the same materials with a particular geometry, involving two rounded notches. This geometry, inspired by the work of Meuwissen et al. (1998) for tension tests on metals,promotes the localisation of shear strain in simple compression before fracture. Two different materials were studied: a natural rock of volcanic origin (Neapolitan Tuff) and an artificial “rock” (CPIR09).In the studies presented, three full-field measurement techniques have been employed in combination: (i) the Digital Image Correlation (DIC), for measurement of kinematic fields at a sample's surface; (ii)acoustic Emission measurements (AE) and AE source location, to follow the evolution of damage insamples during loading; (iii) X-ray tomography (pre-and post-mortem studies), to characterise preexisting defects and discontinuities in the specimens and to better understand the fracturing in 3D.
74

An Examination of the Community School Model in an Urban School Setting

Nicely, Tanna H 01 May 2016 (has links)
The topic of educating today’s youth has become an increasing multi-faceted task with rigorous accountability metrics handed down from all of the different branches of government. Schools are faced with providing more than just instructing the three R’s; they are taxed with educating the whole child. This qualitative study explored the community schools model in an urban elementary school. Specifically, the study attempted to understand the perceived impact this model has on community members, parents, and administrators at one particular elementary school. Data were collected through a series of open-ended interviews and coded for inductive analysis. There were four emerging themes: impact of leader, hub of the community, safe environment, and education of the whole child, which surfaced from the data analysis of the open-ended interviews. A document review also provided additional information that was included in the findings. The need for additional quantitative and qualitative research was also suggested.
75

Determinantes de la percepción del nivel de endeudamiento de los individuos y hogares chilenos

Medel Manríquez, Elisa María 11 1900 (has links)
TESIS PARA OPTAR AL GRADO DE MAGISTER EN FINANZAS FULL TIME / Actualmente, las instituciones financieras utilizan un set acotado de criterios de selección para proveer crédito a terceros, en particular, a personas y hogares, en donde, dichas evaluaciones se caracterizan por estar basadas sobre variables objetivas o cuantificables respecto a su medición, tales como, la renta líquida mensual, edad, educación, colaterales, entre otras. Sin embargo, a principios de los noventa, se fortaleció la literatura de behavioural finance o finanzas conductuales, respecto a la relevancia de considerar sobre este set, variables subjetivas o no cuantificables al momento de seleccionar a los individuos que se les asignaba o no crédito; ya que éstas revelan información pasada sobre las actitudes y motivaciones para demandar o incrementar la necesidad de recursos sobre estas entidades. Ahora bien, en conjunto, las utilizaciones de ambos grupos de información conforman el historial de comportamiento relevante de un individuo, el que puede ser colapsado como la percepción de endeudamiento. Este resultado cognitivo, el cual es conocido en el presente, estará determinado tanto por las características objetivas como subjetivas del entrevistado y, dado dicho conocimiento de esta evaluación individual, se podrá predecir la trayectoria del comportamiento futuro del consumidor de deuda. Por ello, conocer cuáles son los determinantes de la percepción del nivel de endeudamiento, permitirá construir una mejor herramienta de selección (escala métrica de default y de morosidad) tanto para agentes financieros, quienes podrán utilizarla en el otorgamiento de recursos a los solicitante reduciendo así, el riesgo de crédito de las instituciones financieras, como para los académicos, quienes podrán usar esta herramienta en estimaciones del acceso al crédito, demanda de crédito y morosidad que presenten sesgo de selección o problemas de endogeneidad.
76

Survival Strategies for Small Independent Full-Service Restaurants

Nizam, Haitham 01 January 2017 (has links)
Small businesses play a vital role in the modern economy. They represent the main catalyst for economic development. However, small businesses fail at a high rate, especially small independent restaurants. Around 25% of small independent restaurants fail within the first year of operation, and around 60% do not survive for more than 3 years. The purpose of this multiple case study was to explore what strategies small independent full-service restaurant owners in the Al Rehab District, Cairo, Egypt implemented to sustain operations for more than 5 years. The restaurant viability model provided the conceptual framework for this study. The population of this study comprised of 14 owners of small independent full-service restaurant with less than 50 employees in the Al Rehab District, Cairo, Egypt, who sustained their businesses operations for more than 5 years. The data sources included semistructured interviews, restaurant review websites, and social media platforms. Based on methodological triangulation of the data sources, open coding, analyzing the data using qualitative data analysis software, and member checking, 5 themes emerged: restaurant infrastructure strategies, marketing strategies, operations strategies, management strategies, and emotive strategies. The potential implications for positive social change include increasing the success rate of small independent restaurant owners, which in return will create wealth for the owners, generate employment opportunities, increase the government tax revenues, and contribute to the growth of the Egyptian economy.
77

Halltider : Eskilstunas handboll- och innebandyföreningars tillgång till 40x20 planer

Petersson, Petrus January 2010 (has links)
<p>For youths leisure activity the organized sport is vital. Young people become increasingly sedentary</p><p>and the healths of young people are the various municipalities responsibility. In Eskilstuna, the</p><p>handball is very popular but there are only three grounds that meet the standards of the dimensions of</p><p>a handball pitch, 40x20 meters. The same dimensions are used by floorball. Eskilstuna municipality</p><p>owns one of these, the other two is privately built and owned and the municipality rents time in the</p><p>halls.</p><p>IF Guif and HK Eskil are two handballclubs in the central part of Eskilstuna. They have access to only</p><p>one 40x20 meters pitch that they have to share between their 45 teams. Hence forth the handball</p><p>player’s in Eskilstuna rarely has the opportunity to practise at full-size pitches before they reach junior</p><p>age. In the part of Eskilstuna called Torshälla, the situations for another handballclubb is much better.</p><p>Gökstens BK uses the full-sized Ellfolkarenan together with Torshälla IBK, a floorballclub. The new</p><p>built Ellfolkarenan has been a big boast for Gökstens BK and they are now pleased white their access</p><p>to practice areas.</p><p>Floorballclubs in Eskilstuna have, due to private construction, access to two full-sized halls. In</p><p>addition, they are practising in halls which are just below the authorized dimensions. Despite this, they</p><p>have difficulties to get access to the new hall times to expand their club by starting up new teams with</p><p>practise at attractive times of the day.</p><p>With only three full-sized halls, Eskilstuna is among the big-sized municipalities in Sweden with most</p><p>people per full-sized hall. If a new multipurposearena with three pitches would be built in Eskilstuna,</p><p>the municipality would count themselves by those of the big-seized municipalities that are below</p><p>average of people per full-sized hall.</p>
78

A survey of pastors regarding their physical health /

Park, Woo Sung, January 2005 (has links)
Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Translated from Korean. Includes bibliographical references (leaves 181-185).
79

[A survey of pastors regarding their physical health] /

Park, Woo Sung, January 2005 (has links)
Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Includes bibliographical references (leaves 178-181).
80

Increasing knowledge of the biblical basis for accomplishing relief ministries /

Yoo, Hwacheong, January 2005 (has links)
Applied research project (D. Min.)--School of Theology and Missions, Oral Roberts University, 2005. / Includes abstract and vita. Includes bibliographical references (leaves 189-196).

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