As the foundation for a new computational implementation, we survey the calculation of the complex electrical conductivity tensor based on the Kubo-Greenwood (KG) formalism (Kubo, 1957; Greenwood, 1958), with emphasis on derivations and technical aspects pertinent to use of projector augmented wave datasets with plane wave basis sets (BIlichl, 1994). New analytical results and a full implementation of the KG approach in an open-source Fortran 90 post-processing code for use with Quantum Espresso (Giannozzi et al., 2009) are presented. Named KGEC ([K]ubo [G]reenwood [E]lectronic [C]onductivity), the code calculates the full complex conductivity tensor (not just the average trace). It supports use of either the original KG formula or the popular one approximated in terms of a Dirac delta function. It provides both Gaussian and Lorentzian representations of the Dirac delta function (though the Lorentzian is preferable on basic grounds). KGEC provides decomposition of the conductivity into intra- and inter band contributions as well as degenerate state contributions. It calculates the dc conductivity tensor directly. It is MPI parallelized over k-points, bands, and plane waves, with an option to recover the plane wave processes for their use in band parallelization as well. It is designed to provide rapid convergence with respect to k-point density. Examples of its use are given.

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Aerospace structural components made from polymer matrix composites (PMCs) offer numerous advantages. Their high stiffness and high strength combined with low densities enable lower fuel consumption coupled with higher payloads. As a result, PMCs provide an important economic advantage over typical metallic airframes. Textile reinforcements for PMCs are made by assembling reinforcement fibres, typically carbon. Then, the textile reinforcements are typically cut into smaller pieces, stacked, draped and assembled into a dry assembly called a preform, the shape of which generally approaches that of the PMC part to be made. This manufacturing process is labour intensive and expensive. Novel thick, net-shape, drapable, high vf textile reinforcements used toward manufacturing aerospace PMCs are being developed at the University of Ottawa. The technology enables the manufacturing of flat, drapable multilayered near net-shape preforms. The bending and in-plane shear behaviours of such novel thick reinforcement textiles was investigated to understand and define the behaviour of such thick fabric reinforcements when formed into required shapes. A bending apparatus was developed for investigating the bending behaviour of these novel thick reinforcement fabrics and an articulated frame shear rig was used for investigating the in-plane shear behaviour. A non-destructive inspection method using infrared imaging was used for investigating and identifying flaws and defects in these thick, dry textile reinforcements, aiming at increasing the quality and reproducibility of the final PMC parts made from these reinforcements.

Technical textiles are increasingly being engineered and used in challenging applications, in areas such as safety, biomedical devices, architecture and others, where they must meet stringent demands including excellent and predictable load bearing capabilities. They also form the bases for one of the most widespread group of composite materials, fibre reinforced polymer-matrix composites (PMCs), which comprise materials made of stiff and strong fibres generally available in textile form and selected for their structural potential, combined with a polymer matrix that gives parts their shape. Manufacturing processes for PMCs and technical textiles, as well as parts and advanced textile structures must be engineered, ideally through simulation, and therefore diverse properties of the textiles, textile reinforcements and PMC materials must be available for predictive simulation. Knowing the detailed geometry of technical textiles is essential to predicting accurately the processing and performance properties of textiles and PMC parts. In turn, the geometry taken by a textile or a reinforcement textile is linked in an intricate manner to its constitutive behaviour. This thesis proposes, investigates and validates a general numerical tool for the integrated and comprehensive analysis of textile geometry and constitutive behaviour as required toward engineering applications featuring technical textiles and textile reinforcements. The tool shall be general with regards to the textiles modelled and the loading cases applied. Specifically, the work aims at fulfilling the following objectives: 1) developing and implementing dedicated simulation software for modelling textiles subjected to various load cases; 2) providing, through simulation, geometric descriptions for different textiles subjected to different load cases namely compaction, relaxation and shear; 3) predicting the constitutive behaviour of the textiles undergoing said load cases; 4) identifying parameters affecting the textile geometry and constitutive behaviour under evolving loading; 5) validating simulation results with experimental trials; and 6) demonstrating the applicability of the simulation procedure to textile reinforcements featuring large numbers of small fibres as used in PMCs. As a starting point, the effects of reinforcement configuration on the in-plane permeability of textile reinforcements, through-thickness thermal conductivity of PMCs and in-plane stiffness of unidirectional and bidirectional PMCs were quantified systematically and correlated with specific geometric parameters. Variability was quantified for each property at a constant fibre volume fraction. It was observed that variability differed strongly between properties; as such, the simulated behaviour can be related to variability levels seen in experimental measurements. The effects of the geometry of textile reinforcements on the aforementioned processing and performance properties of the textiles and PMCs made from these textiles was demonstrated and validated, but only for simple cases as thorough and credible geometric models were not available at the onset of this work. Outcomes of this work were published in a peer-reviewed journal [101]. Through this thesis it was demonstrated that predicting changes in textile geometry prior and during loading is feasible using the proposed particle-based modelling method. The particle-based modelling method relies on discrete mechanics and offers an alternative to more traditional methods based on continuum mechanics. Specifically it alleviates issues caused by large strains and management of intricate, evolving contact present in finite element simulations. The particle-based modelling method enables credible, intricate modelling of the geometry of textiles at the mesoscopic scale as well as faithful mechanical modelling under load. Changes to textile geometry and configuration due to the normal compaction pressure, stress relaxation, in-plane shear and other types of loads were successfully predicted. During simulation, particles were moved randomly until a stable state of minimum strain energy in the system was reached; as particles moved upon iteration, the configuration of fibres in the textile changed under constant boundary conditions. Then boundary conditions were altered corresponding to strains imposed on the textile, and the system was iterated again towards a new state of minimum strain energy. The Metropolis algorithm of the Monte Carlo method was adopted in this specific implementation. The method relies on a statistical approach implemented in computational algorithms. In addition to geometrical modelling, the proposed particle-based modelling method enables the prediction of major elements of the constitutive behaviour of textiles and textile reinforcements. In fact, prediction of the constitutive behaviour is integral to the prediction of the meso-scale geometry. Simulation results obtained from the proposed particle-based modelling method were validated experimentally for yarns, single-layer textiles and multi-layer textiles undergoing compaction. Validation work showed that the particle-based modelling method replicates reality very faithfully, and it also showed the suitability of including Gutowski's function along with Hertz' function for representing lateral compaction of yarns. The procedure and results were accepted in final form for publication in a peer reviewed journal [104]. The capability of the proposed particle-based modelling method towards replicating the time-dependent relaxation and reconfiguration of woven textiles subjected to compaction loading was investigated. The capability, which was demonstrated for single and double-layers of plain woven textiles, is intrinsic to the modelling method. The method is unique in the fact that in contrary to work previously reported in the literature, it models the compaction and the relaxation seamlessly in the same simulations and environment. This work is being finalised towards submission for publication in a peer reviewed journal [103]. The proposed particle-based modelling method was also used for modelling in-plane shear in woven textiles. Simulation results were validated experimentally for a single-layer plain woven textile. Validation work showed that the particle-based modelling method reproduces experimental data and published trends very well. A novel algorithm for modelling friction was introduced, leading to results being obtained from a significantly less computationally demanding procedure in these simulations. This work was submitted for publication in a peer reviewed journal [102]. Finally the thesis discusses early work towards the application of the method to carbon fibre fabrics through the description of expansion algorithm (EA) to be used in modelling textiles made of yarns featuring very large numbers of fibres. Furthermore, additional modelling work is presented towards further manufacturing process involving technical textiles, namely textile bending and punching. The latter part is presented as early steps towards future work.

Conventional rectangular waveguides are commonly used for high power and millimetre wave microwave applications. However their use at lower frequencies has been limited by their bulky nature at these frequencies. A new type of compact waveguide called a partial H-plane waveguide has previously been proposed that has only one quarter of the cross sectional area of a conventional waveguide. However, only limited information relating to the feeding of such waveguides is available. This study focuses on the development of a practical end-launched coaxial and a microstrip to partial H-plane waveguide adapters with similar or larger achievable bandwidths compared to conventional waveguide probe feed adapters. The two proposed waveguide transition geometries are investigated to determine which parameters can be used to optimise the insertion and return losses. The prototype waveguide transitions were optimised using numerous simulations and fabricated in the back-to-back configuration. Simulated single ended and back-to-back S-parameters yield good performance over the entire H-band (3.95 to 5.85 GHz, also known as G-Band). De-embedding techniques are used to measure the approximate single ended response of the two waveguide adapters based on the back-to-back measurements. The measurement and simulation results compare favourably and validate the designs. / Dissertation (MEng)--University of Pretoria, 2014. / tm2015 / Electrical, Electronic and Computer Engineering / MEng / Unrestricted

Detecção automática de regiões planares em nuvens de pontos é um importante passo para muitas aplicações gráficas, de processamento de imagens e de visão computacional. Enquanto a disponibilidade de digitalizadores a laser e a fotografia digital tem nos permitido capturar nuvens de pontos cada vez maiores, técnicas anteriores para detecção de planos são computacionalmente caras, sendo incapazes de alcançar desempenho em tempo real para conjunto de dados contendo dezenas de milhares de pontos, mesmo quando a detecção é feita de um modo não determinístico. Apresentamos uma abordagem determinística para detecção de planos em nuvens de pontos não estruturadas que apresenta complexidade computacional O(n log n) no número de amostras de entrada. Ela é baseada em um método eficiente de votação para a transformada de Hough. Nossa estratégia agrupa conjuntos de pontos aproximadamente coplanares e deposita votos para estes conjuntos em um acumulador esférico, utilizando núcleos Gaussianos trivariados. Uma comparação com as técnicas concorrentes mostra que nossa abordagem é consideravelmente mais rápida e escala significativamente melhor que as técnicas anteriores, sendo a primeira solução prática para detecção determinística de planos em nuvens de pontos grandes e não estruturadas. / Automatic detection of planar regions in point clouds is an important step for many graphics, image processing, and computer vision applications. While laser scanners and digital photography have allowed us to capture increasingly larger datasets, previous techniques are computationally expensive, being unable to achieve real-time performance for datasets containing tens of thousands of points, even when detection is performed in a non-deterministic way. We present a deterministic technique for plane detection in unorganized point clouds whose cost is O(n log n) in the number of input samples. It is based on an efficient Hough-transform voting scheme and works by clustering approximately co-planar points and by casting votes for these clusters on a spherical accumulator using a trivariate Gaussian kernel. A comparison with competing techniques shows that our approach is considerably faster and scales significantly better than previous ones, being the first practical solution for deterministic plane detection in large unorganized point clouds.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2015-12-10T09:55:29Z No. of bitstreams: 1 ricardomiranda.pdf: 11833361 bytes, checksum: 783c039ddbcf08463f32cc25571b6cc6 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2015-12-10T14:03:59Z (GMT) No. of bitstreams: 1 ricardomiranda.pdf: 11833361 bytes, checksum: 783c039ddbcf08463f32cc25571b6cc6 (MD5) / Made available in DSpace on 2015-12-10T14:03:59Z (GMT). No. of bitstreams: 1 ricardomiranda.pdf: 11833361 bytes, checksum: 783c039ddbcf08463f32cc25571b6cc6 (MD5) Previous issue date: 2015-07-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Visando proporcionar uma melhor metodologia para trabalhar os conteúdos matemáticos, de forma a tornar-se compreensível para os alunos, este trabalho apresenta uma forma diferente e criativa de compreender conceitos de áreas e de perímetros de figuras planas, tendo como recurso a utilização do Tangram. O uso de jogos tornam as aulas mais dinâmicas e atraentes, despertando o interesse dos alunos e contribui significativamente na formação de conceitos e conhecimentos. O jogo do Tangram, é um importante recurso como material lúdico no ensino da Matemática, priorizando a Geometria Plana e a sua aplicabilidade no dia-a-dia, apresentamos atividades que, além de trabalhar os conceitos citados acima, visam desenvolver o raciocínio lógico geométrico, a criatividade e habilidades como, a interdisciplinaridade, a disciplina, a concentração, trabalho em equipe, entre outras, importantes para a formação geral do aluno. / In order to provide a better methodology to work the mathematical content in order to become understandable for the students, this work presents a different and creative way to understand concepts of area and perimeter of plane figures, using Tangram. The use of games make the classes more dynamic and attractive, arousing the interest of students and contributes significantly in the formation of concepts and knowledge. The Tangram’s game is an important resource as play material in the teaching of Mathematics. It’s prioritizing the plane geometry and its application in all the classes, in addition to working the concepts mentioned above, aimed at developing the geometric logical reasoning, creativity and skills as interdisciplinarity, discipline, concentration, teamwork, among others, important to the overall education of the student.

Objective: To determine the association of features occlusal with age and gender in children with deciduous dentition of a public educational institution in the district of Ate Vitarte in 2013. Methods: The sample was conformed by 108 children with complete deciduous dentition between 3 and 5 years of the IE Amauta No. 1285-216 located in Ate Vitarte in 2013. All variables were recorded on the data collection form, these were, type of arch, primate spaces, palatine hall relation of molars, bilateral terminal molar relation, bilateral canine relationship, curve of Spee, midline, overjet and overbite. In addition to the age and gender of the scholar. Frequencies were obtained and the chi square test were conducted to determine associations between variables. Results:. Only found statistically significant association between superior primates spaces (p=0.041) and inferior (0.002), bilateral terminal molar relation (p=0.040), lower midline (p=0.032) and age. Conclusions: In this study, was found that most of the children presented normal occlusal characteristics. No association of most occlusal characteristics were found with age and gender. / Objetivo: Determinar la asociación de las características oclusales con la edad y género en niños con dentición decidua de una Institución Educativa Pública del distrito de Ate Vitarte en el año 2013. Métodos: La muestra estuvo conformada por 108 niños con dentición decidua completa entre 3 y 5 años de la IE Amauta Nº 1285-216 ubicado en Ate Vitarte en el 2013. Todas las variables fueron registradas en la ficha de recolección de datos, estas fueron el tipo de arco, los espacios primates, relación vestíbulo palatina de molares, plano terminal bilateral, relación canina bilateral, curva de Spee, línea media, overjet y overbite. Además de la edad y género del escolar. Se obtuvo las frecuencias y se realizó la prueba de chi cuadrado para determinar asociaciones entre las variables. Resultados: Se encontró asociación estadísticamente significativa entre los espacios primates superior (p=0.041) e inferior (p=0.002), plano terminal bilateral (p=0.040) y la línea media inferior con la edad (p=0.032). Conclusiones: Se encontró asociación de los espacios primates superior e inferior, plano terminal bilateral y la línea media inferior con la edad. Palabras Claves: Dentición decidua, relación oclusal, plano terminal, espacios primates / Tesis

This master’s thesis deals with the design of installation of floats for the M-4 Irbis airplane and it’s modification in aim to provide water level landing. Part of this thesis is selection of geometry of floats, weight analysis of the modified version and stress analysis of structural elements. The aim was to perform modification on a float plane which will have a minimal impact on the airframe and to meet the requirements of Certification Specification ASTM F2245 and CS-VLA. In conclusion, the hydrodynamic and aerodynamic characteristics including flight performance is determined. Final part is devoted to the design of the rudder for directional control of the floats.

Title: Effect of Kinesio Taping on the functional condition of the musculoskeletal system The concept of the problem: The kinesiotaping method is currently very popular therapeutic method in sport as well as in physiotherapy. Although this method was primarily developed as therapeutic method, there is only a few studies, in which the kinesiotaping method is used on healthy individuals. Objective: The objective of this thesis is to evaluate the immediate effect of applied kinesio tape on changes in the range of motion of the thoracic spine in the sagittal plane on healthy individuals. Methods: The theoretical part deals with summary of the taping method as well as with anatomical and kinesiological aspects of flexion and extension of the thoracic spine. The practical part as an experiment (single blinded controlled trial) is dedicated to the application of kinesio and placebo tape, the way that both tapes were applied was specifically designed for the purpose of this thesis and for specifically selected individuals. For gathering the data and for the evaluation the changes in the range of motion, the index of thoracic spine mobility was used. Results: For experimental group - kinesio tape there were no statistically significant increase in the range of motion. Vice versa, according to the obtained...