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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.
111

Alternative characterizations of weak infinite-dimensionality and their relation to a problem of Alexandroff's /

Rohm, Dale M. January 1987 (has links)
Thesis (Ph. D.)--Oregon State University, 1987. / Typescript (photocopy). Includes bibliographical references (leaves 97-101). Also available on the World Wide Web.
112

Modelling ocean circulation with large-scale semi-geostrophic equations

Shepherd, James Robert January 1999 (has links)
The Large-scale Semi-Geostrophic Equations (LSGE, Salmon[73]) are three-dimensional equations valid for an ocean with a rigid lid and length scales much greater than the internal deformation radius (about 40km). In this thesis I reduce the LSGE to a pair of two-dimensional equations via the ansatz that the temperature is independent of the vertical co-ordinate. I refer to these as the Depth-Independent-Temperature (DIT) equations. Whilst this is regarded as a paradigm for the entire ocean, the reduction is similar in spirit to that utilised by many authors for modelling the mixed layer of the ocean. The equations of this thesis differ from the work of such mixed layer models because they involve no ad hoc vertical averaging and so solutions to these equations are also solutions to the full three-dimensional LSGE. The DIT are arguably the simplest equations for ocean circulation to include the effects of inertia, topography and baroclinicity. The DIT are studied both analytically and numerically. It is shown that the model exhibits baroclinic instabilities and analogies are drawn with classical Rayleigh-Benard convection. It is shown that both viscosity and thermal diffusivity are required to avert an ultra-violet catastrophe. Numerical simulations of turbulence demonstrate that the long-time behaviour resembles barotropic flow and that the temperature is reduced to the role of a passive tracer unless large-scale thermal structure is imposed externally on the flow. One of the advantages of the current model over the more widely used quasi-geostrophic models is that there is no restriction on the vertical extent of the bottom topography. This allows the simulation of idealised oceanic basin circulations in which the depth of the ocean vanishes smoothly at boundaries. These ocean simulations are used to study the sensitivity of the model to the Rossby Number, Ekman Number and forcing parameters. Comparison of a barotropic and a DIT ocean reveals the influence of baroclinicity in the latter model. Characteristic features of the Gulf Stream such as meandering, recirculation gyres and the shedding of warm and cold core rings are reproduced by the DIT model and the simple nature of the equations permits an interpretation of these features.
113

An evaluation of 3D building modelling and visualisation packages for enhancing public participation within the planning process

Mantle, Emma Jane January 2007 (has links)
This thesis will look at the importance of 3D Visualization within the planning process and addresses the issue of improving public participation within urban regeneration. The main aim of this research is therefore to discover what type of model the public require in terms of understanding future developments, which may in turn help them engage in the planning process. In order to achieve the main aim several other aims need to be established, such as; identifying the capacity of the profession in Wales to deliver 3D models of urban environments, evaluating software solutions to create 3D models of urban environments, and to explore emerging techniques that might contribute to the efficiency and economy of producing models of urban environments. These aims were realised through conducting surveys which targeted the Building Design Profession (BDP) and established which software packages were being used and for what purpose. A second survey was also conducted by means of an exhibition, which aimed to establish what the public require in regards to being presented with proposed developments. Other aims were realized through conducting trials. These examined the usability of different 3D CAD packages and the possibility of integrating CAD data with GIS, and how it could be used to quicken the modeling process. Results from these trials showed that through the use of workarounds there are possibilities of integrating CAD and GIS data. The research reported here indicates that members of the public have trouble understanding 2D Plans and Elevations and the data consistently demonstrates that more than 40% of participants chose 3D technology as a more understandable method of being shown future developments. The results from the two surveys show that although the majority (42.4%) of participants selected 3D technology as their preferred option, only 28% of participating Building Design Professionals in Wales use 3D computer packages, albeit not for presenting propose urban regeneration projects to the public. From the outset of this research the purpose has been to evaluate whether public participation will be increased if 3D technologies are provided to showcase proposed developments. The more efficient the modelling process, the more feasible and likely it will be that 3D CAD will one day be a paramount tool within the Planning Process. Numerous techniques were included to examine this efficiency.
114

3D imaging in forensic odontology

Evans, Sam January 2012 (has links)
This work describes the investigation of a new 3D capture method for acquisition and subsequent forensic analysis of bite mark injuries on human skin. When documenting bite marks with standard 2D cameras, errors in photographic technique can occur if best practice is not followed. Subsequent forensic analysis of the mark is problematic when a 3D structure is recorded in a 2D space. A 3D image capture and processing system might avoid the problems resulting from the 2D reduction process, simplifying the guidelines and reducing errors. The proposed solutions in this work are: conducting a review of the current 2D and three 3D capture methods, also a series of benchmarks for system assessment. Followed by a series of performance evaluations of the existing current 2D and two 3D methods. Further proposed solutions include, the design of a system specification for the practical reproducible acquisition of bite mark injuries. Finally a review of the validation process for forensic evidence presented to the courts. The results of the work are as follows: A 3D system is required to produce the correct 3D data of a bite mark and suspect dentition for forensic analysis. Such a system should be practical and consistent, if it is to replace the current de facto 2D systems. The MAVIS hardware can be considered a practical and consistent solution for producing the required 3D image of a bite mark for analysis; however, the MAVIS hardware cannot produce a satisfactory 3D image of a dental cast. At present a laser scanner is required to produce satisfactory results of a dental cast. Angular distortion and errors created by the user in 2D image capture can hinder the digital measurement process. 3D capture therefore introduces less operator error in the form of angular distortion.
115

Vliv teploty ovzduší na množství vyprodukovaného tepla a elektrické energie v podniku Teplárny Brno, a.s.

Vinklerová, Markéta January 2011 (has links)
No description available.
116

Análise da dimensionalidade e modelagem multimensional pela TRI no antigo ENEM

Costa, Carlos Eduardo Sousa January 2015 (has links)
Dissertação (mestrado profissional) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Métodos e Gestão em Avaliação, Florianópolis, 2015. / Made available in DSpace on 2016-10-19T13:05:28Z (GMT). No. of bitstreams: 1 338285.pdf: 2513554 bytes, checksum: fdded9a350387a19f94cadf3fa640b4d (MD5) Previous issue date: 2015 / No presente estudo utilizou-se uma modelagem multidimensional do Exame Nacional do Ensino Médio (ENEM), por meio da Teoria da Resposta ao Item multidimensional (TRIM) com o objetivo de melhor compreender o aprendizado do avaliado. O ENEM (1998-2008) era um exame interdisciplinar estruturado por cinco competências expressas por 21 habilidades. Assim, por ser uma avaliação em que não podemos, a priori, considerar unidimensional, realizou-se uma análise da dimensionalidade e interpretação de suas dimensões. Inicialmente foi analisado o conjunto de 63 itens da prova amarela do ENEM 2001 em uma amostra de 10.000 respondentes. Nessa fase foi abordada a dimensionalidade da prova e a escolha do modelo que melhor se ajustava aos dados. Em seguida, foi ajustado um modelo multidimensional da TRI, com cinco dimensões, e foi feita uma relação das competências da prova do ENEM com os fatores, por meio da analise dos itens da prova. Nesta relação ficou evidenciada uma relação mais expressiva das cinco competências com somente três dimensões. Por último, foi feita uma comparação dos avaliados que acertaram 40, 50 e 60 itens na prova, através da analise da porcentagem do número de acerto em cada competência e escores, estimados por meio dos modelos multidimensionais da TRI, em cada uma das cinco dimensões, com a finalidade de interpretar o desempenho desses avaliados.<br> / Abstract : In the present study we used a multi-dimensional modeling of the National Examination of Secondary Education (ENEM), through multidimensional item response theory (MIRT) in order to better understand the learning assessed. The ENEM (1998-2008) was an interdisciplinary examination structured for five competencies expressed by 21 skills. So, being an assessment, we can not, a priori, to consider one-dimensional, there was an analysis of dimensionality and interpretation of its dimensions. Initially we analyzed the set of 63 items Yellow proof of ENEM 2001 on a sample of 10,000 respondents. In this phase it addressed the dimensionality of proof and choosing the model that best fit the data. Then a multidimensional model of TRI was adjusted with five dimensions, and was made a list of ENEM proof competencies with the factors through the analysis of the test items. This relationship was evidenced a more significant relationship of the five competencies with only three dimensions. Finally, a comparison of the assessed was made that hit 40, 50 and 60 items in the race through the analysis of the percentage of the hit number in each jurisdiction and scores, estimated by the multidimensional IRT models in each of the five dimensions in order to interpret the performance of these reviews.
117

LAD - linguagem para analise dimensional

Ferrari, Jose Osvaldo 14 July 2018 (has links)
Orientador: Nelson Castro Machado / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Ciencia da Computação / Made available in DSpace on 2018-07-14T09:04:20Z (GMT). No. of bitstreams: 1 Ferrari_JoseOsvaldo_M.pdf: 4174313 bytes, checksum: 025764adfbdcc61583d5b3e5747ea4d9 (MD5) Previous issue date: 1973 / Resumo: O presente trabalho descreve o Sistema LAD (Linguagem para Análise Dimensional) destinado à solução de problemas ligados à Análise Dimensional através da utilização de um computador digital de grande porte em "time-sharing". Problemas envolvendo conversão de unidades ou cálculo de relações entre grandezas podem ser rapidamente resolvidos em modo conversacional pelo sistema que fornece ainda opções para: saída de resultados em vários formatos, listagem de programas fonte ou armazenamento de programas para uso futuro. Os comandos, cuja forma é bastante próxima à notação usada em Análise Dimensional, são poucos e simples, tornando extremamente fácil seu aprendizado e utilização por pessoas não especializadas era computação. / Abstract: Not informed. / Mestrado / Mestre em Ciência da Computação
118

Homotopy string links over surfaces

Yurasovskaya, Ekaterina 11 1900 (has links)
In his 1947 work "Theory of Braids" Emil Artin asked whether the braid group remained unchanged when one considered classes of braids under linkhomotopy, allowing each strand of a braid to pass through itself but not through other strands. We generalize Artin's question to string links over orientable surface M and show that under link-homotopy surface string links form a group PBn(M), which is isomorphic to a quotient of the surface pure braid group PBn(M). Surface braid groups and their properties are an area of active research by González-Meneses, Paris and Rolfsen, Goçalves and Guaschi, and our work explores the geometric and visual beauty of this subject. We compute a presentation of PBn(M) in terms of the generators and relations and discuss the orderability of the group in the case when the surface in question is a unit disk D. / Science, Faculty of / Mathematics, Department of / Graduate
119

Efficiency of statistics of stereology

Downie, Alan Stewart January 1991 (has links)
No description available.
120

Utilisation des données 3D pour la reconnaissance du visage / Utilization of 3D data in face recognition

Erdogmus, Nesli 20 March 2012 (has links)
Avec l’augmentation des applications de sécurité, un sujet particulier a attiré plus d’attention que de nombreux autres domaines en reconnaissance de formes : la biométrie – la reconnaissance des personnes en fonction de leur physique et/ou de leurs traits comportementaux. Parmi ces traits, le visage se distingue par un compromis favorable entre accessibilité et fiabilité. Dans cette thèse, nous avons principalement travaillé sur une modalité relativement plus récente en reconnaissance du visage : la forme 3D. Plus avantageuse que son homologue en 2D, car intrinsèquement invariant aux changements d’illumination de pose, l’analyse 3D du visage se heurte encore à des défis majeurs tels que les déformations de surface du visage dues aux expressions ou occultations. En conséquence, une étude approfondie est effectuée sur ce sujet incluant le prétraitement des données 3D du visage, l’annotation automatique, la simulation d’altération et d’expressions en 3D, l’extraction de caractéristiques 3D et l’analyse locale de surface. / As the need and investment for security applications grow vastly, one particular topic has certainly been attracting higher attention than many other pattern recognition fields: biometrics – recognition of humans based on their physical and/or behavioral traits. Among those traits, face stands out with its favorable reconcilement between accessibility and reliability. In this doctoral dissertation, we principally investigate 3D shape which is a relatively more recent modality in face recognition. Being advantageous to its 2D counterpart for being intrinsically invariant to illumination and pose changes, 3D face recognition still encounters major challenges such as acquisition inadequacy or facial surface deformations due to expressions or occlusion. Bearing those in mind, a thorough study is carried out on this topic, including pre-processing of 3D facial data, automatic landmarking, facial expression and alteration simulations in 3D, 3D feature extraction and 3D regional surface analysis.

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