Submitted by Kamila Costa (kamilavasconceloscosta@gmail.com) on 2015-06-18T20:37:32Z No. of bitstreams: 1 Dissertação-Euderley de C Nunes.pdf: 25821021 bytes, checksum: 4f3d1be54be4ba8e8d8c720131d61fb6 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-06T17:47:02Z (GMT) No. of bitstreams: 1 Dissertação-Euderley de C Nunes.pdf: 25821021 bytes, checksum: 4f3d1be54be4ba8e8d8c720131d61fb6 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-06T17:54:01Z (GMT) No. of bitstreams: 1 Dissertação-Euderley de C Nunes.pdf: 25821021 bytes, checksum: 4f3d1be54be4ba8e8d8c720131d61fb6 (MD5) / Made available in DSpace on 2015-07-06T17:54:32Z (GMT). No. of bitstreams: 1 Dissertação-Euderley de C Nunes.pdf: 25821021 bytes, checksum: 4f3d1be54be4ba8e8d8c720131d61fb6 (MD5) Previous issue date: 2015-03-04 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aiming to contribute to the teaching of basic education, this work will present a simple approach through the use of a well-known technique in antiquity, which is the stereographic projection. This paper will deal with the studies developed by Georg Friedrich Bernhard Riemann (1826-1866), which demonstrates how to design stereographically a sphere on a plane, called the complex plane. For this, we will show that the use of complex numbers has great relevance for understanding of the techniques commonly used in the development of cartography and other areas. We will present the set of complex numbers and then de ne the stereographic projection and some of its main properties, where we use the Geogebra software version 5.0, seeing that the software produces 3D animations, which will support in understanding the stereographic projection and of their properties by the high school students and teachers. Thus, this research will serve as a motivating element for students and teachers that seek to improve their knowledge because the study by Riemann is based on complex numbers which are studied in the course of primary education. / Com o objetivo de contribuir com o ensino da educação básica, este trabalho apresentará através de uma abordagem simples o uso de uma técnica muito conhecida na antiguidade, que é a projeção estereográ ca. Este trabalho abordará os estudos desenvolvidos por Georg Friedrich Bernhard Riemann (1826-1866), que demonstra como projetar estereogra camente uma esfera sobre um plano, denominado de plano complexo. Para isso, mostraremos que o uso dos números complexos terá grande relevância para compreendermos uma das técnicas mais usadas no desenvolvimento da cartogra a e outras áreas. Apresentaremos o conjunto dos números complexos e em seguida de niremos a projeção estereográ ca e algumas de suas principais propriedades, onde faremos o uso do software Geogebra versão 5.0, visto que este software produz animações em 3D, que servirão de suporte para a compreensão da projeção estereográ ca e de suas respectivas propriedades por parte dos alunos e professores do ensino médio. Com isso, esta pesquisa servirá de elemento motivador para alunos e professores que busquem aprimorar seus conhecimentos, pois o estudo desenvolvido por Riemann tem como base os números complexos que são estudados no decorrer do ensino básico.

A reconstrução tomográfica de imagens com ruído Poisson tem grandes aplicações em medicina nuclear. A demanda por informações mais complexas, como por exemplo, várias secções de um órgão, e a necessidade de reduzir a dosagem radioativa a que o paciente é submetido, requerem métodos adequados para a reconstrução de imagem com baixa contagem, no caso, baixa relação sinal/ruído. A abordagem estatística, utilizando a máxima verossimilhança (ML) e o algoritmo Expectation-Maximization (EM), produz melhores resultados do que os métodos tradicionais, pois incorpora a natureza estatística do ruído no seu modelo. A presente tese apresenta uma solução alternativa, considerando também o modelo de ruído Poisson, que produz resultados comparáveis ao do ML-EM, porém com custo computacional bem menor. A metodologia proposta consiste, basicamente, em se estimar as projeções considerando o modelo de formação das projeções ruidosas, antes do processo da reconstrução. São discutidos vários estimadores otimizados, inclusive Bayesianos. Em especial, é mostrado que a transformação de ruído Poisson em ruído aditivo Gaussiano e independente do sinal (transformação de Anscombe), conjugada à estimativa, produz bons resultados. Se as projeções puderem ser consideradas, aproximadamente, transformadas de Radon da imagem a ser reconstruída, então pode ser aplicado um dos métodos da transformada para a reconstrução tomográfica. Dentre estes métodos, o da aplicação direta da transformada de Fourier foi avaliado mais detalhadamente devido ao seu grande potencial para reconstruções rápidas com processamento vetorial e processamento paralelo. A avaliação do método proposto foi realizada através de simulações, onde foram geradas as imagens originais e as projeções com ruído Poisson. Os resultados foramcomparados com métodos clássicos como a filtragem-retroprojeção, o ART e o ML-EM. Em particular, a transformação de Anscombe conjungada ao estimador heurístico (filtro de Maeda), mostrou resultados próximos aos do ML-EM, porém com tempo de processamento bem menor. Os resultados obtidos mostram a viabilidade da presente proposta vir a ser utilizada em aplicações clínicas na medicina nuclear. / Tomographic reconstruction of images with Poisson noise is in important problem in nuclear medicine. The need for more complete information, like the reconstruction of several sections of an organ, and the necessity to reduce patient absorbed radioactivity, suggest better methods to reconstruct images with low-count and low signal-to-noise ratio. Statistical approaches using Maximum Likelihood (ML) and the Expectation-Maximization (EM) algorithm lead to better results than classical methods, since ML-EM considers in its model the stochastic nature of the noise. This thesis presents an alternative solution, also using a Poisson noise model, that produces similar results as compared to ML-EM, but with much less computational cost. The proposed technique basically consists of projection estimation before reconstruction, taking into account a model for the formation of the noisy projections. Several optimal and Bayesian estimators are analysed. It is shown that the transformation of Poisson noise into Gaussian additive and independent noise (Anscombe Transformation), followed by estimation, yields good results. If the projection can be assumed as Radon transform of the image to be reconstructed, then it is possible to reconstruct using one of the transform methods. Among these methods, the Direct Fourier Method was analysed in detail, due to its applicability for fast reconstruction using array processors and parallel processing. Computer simulations were used in order to access this proposed technique. Phantoms and phantom projections with Poisson noise were generated. The results were compared with traditional methods like Filtering-Backprojection, Algebraic Rconstruction Technique (ART) and ML-EM. Specifically, the Anscombe transformation together with a heuristic estimator (Maeda\'s filter) produced results comparable to ML-EM, but spending only a fraction of the processing time.

Deteriorating air quality is one of the major problems faced worldwide and in particular in Asia. The world's most polluted megacities are located in Asia highlighting the urgent need for efforts to improve the air quality. New Delhi (India), one of the world's most polluted cities, was the host of the Common Wealth Games during the period of 4-14 October 2010. This high profile event provided a good opportunity to accelerate efforts to improve air quality. Computational advances now allow air quality forecast models to fully couple the meteorology with chemical constituents within a unified modeling system that allows two-way interactions. The WRF-Chem model is used to simulate air quality in New Delhi. The thesis focuses on evaluating air quality and meteorology feedbacks. Four nested domains ranging from South Asia, Northern India, NCR Delhi and Delhi city at 45km, 15km, 5km and 1.67km resolution for a period of 20day (26thsep-15thoct, 2010) are used in the study. The predicted mean surface concentrations of various pollutants show similar spatial distributions with peak values in the middle of the domain reflecting the traffic and population patterns in the city. Along with these activities, construction dust and industrial emissions contribute to high levels of criteria pollutants. The study evaluates the WRF-Chem capabilities using a new emission inventory developed over Delhi at a fine resolution of 1.67km and evaluating the results with observational data from 11 monitoring sties placed at various Game venues. The contribution of emission sectors including transportation, power, industry, and domestic to pollutant concentrations at targeted regions are studied and the results show that transportation and domestic sector are the major contributors to the pollution levels in Delhi, followed by industry. Apart from these sectors, emissions outside of Delhi contribute 20-50% to surface concentrations depending on the species. This indicates that pollution control efforts should take a regional perspective. Air quality projections in Delhi for 2030 are investigated. The Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model is used to generate a 2030 future emission scenario for Delhi using projections of air quality control measures and energy demands. Net reductions in CO concentrations by 50%, and increases of 140% and 40% in BC and NOx concentrations, respectively, are predicted. The net changes in concentration are associated with increases in transport and industry sectors. The domestic sector still has a significant contribution to air pollutant levels. The air quality levels show a profound effect under this scenario on the environment and human health. The increase in pollution from 2010 to 2030 is predicted to cause an increase in surface temperature by ~0.65K. These increasing pollution levels also show effects on the radiative forcing. The high aerosols loading i.e. BC, PM2.5 and PM10 levels show strong influence on the short and longwave fluxes causing strong surface dimming and strong atmosphere heating due to BC. These results indicate transport and domestic sectors should be targeted for air quality and climate mitigations.

Orientador: Elias Leite Mendonça / Resumo: Neste trabalho propomos uma base de operadores de projeção e transição de spin para tensores de rank-3. Utilizaremos essa base para determinar os coeficientes da densidade de lagrangiana do modelo de Singh-Hagen (SH). Forneceremos uma expressão geral para obtenção do propagador para teorias de rank-3 via tensor totalmente simétrico sem quebra de paridade. Além disso, realizaremos o processo de Imersão de Calibre de Noether (ICN) no modelo SH em D dimensões e verificaremos seu conteúdo físico. Por fim iremos verificar o conteúdo físico de um novo modelo de dubleto de spin-3 de sexta ordem obtido pelo processo de solda dos modelos auto-duais de quinta e sexta ordem que não necessitam de campos auxiliares. / Abstract: In this work we suggest a basis of spin projection and transition operators for rank-3 tensors. We use it in order to determine the coefficients of the Singh-Hagen model. We also provide a general expression for obtaining the propagator for rank-3 theories via full symmetric tensor without parity breaking. In addition, we perform the Noether Gauge Embendment (NGE) procedure on the SH model in D dimensions and verify its particle content. Finally we analyze the unitarity of a new sixth-order spin-3 doublet model obtained through the soldering approach of the fifth and sixth order self-dual models which do not require auxiliary fields. / Mestre

Abstract Purpose: The purpose of this paper is to quantify if using an average intensity projection (AIP) scan or a 30% phase (mid-ventilation surrogate, MidV) scan as the reference image for patient position verification affects reproducibility of lung cancer patient alignment under free-breathing cone beam computed tomography (CBCT) image guidance and to analyze the effects of common clinical issues on registration variability. Methods: AIPs were retrospectively created for 16 lung patients (14 SBRT, 2 conventional treatments) originally planned/treated using the 30% phase MidV surrogate scan as reference. The study included 3-5 CBCTs from each patient. Registrations were performed between the AIP-CBCT and between the MidV-CBCT by 5 individuals (student, medical physics resident, medical resident, medical physicist, and attending physician) using MIM 6.2 image registration platform (Beachwood, OH). The images were rigidly registered, internal tumor volume (ITV) contours were displayed, and no rotational adjustments were allowed to reflect real treatment conditions. Additionally, the registrations for AIP-CBCT and MidV-CBCT were repeated 3 times by one individual for intra-observer variability assessment. Patient setup rotations, tumor volume, tumor motion, and breathing variability were estimated for correlation with registration variability. Results: The magnitude of the average intra-observer standard deviations from the lateral (LAT), anterior-posterior (AP), and superior-inferior (SI) directions for the AIP/CBCT and MidV/CBCT registrations were 0.9 mm and 1.2 mm, respectively. The magnitude of the average inter-observer standard deviations for the AIP/CBCT and MidV/CBCT were 1.7 mm and 1.8 mm, respectively. Average discrepancies over the whole population were found to be small; however, some individual patients presented high variability. Patient-specific cases with high variability were analyzed and observations on its potential causes are discussed. Conclusion: The differences in alignment using AIP versus MidV as the reference images are, when averaged over the population studied, very small and clinically irrelevant for PTV margins > 5mm; however, individual patients may be impacted in a clinically relevant manner if smaller margins, 3 mm and below, are used instead.

Optoelectronic devices operating in the mid-wave (3-5 Μm) and long-wave (8-12 Μm) infrared (IR) regions of the electromagnetic spectrum are of a great interest for academic and industrial applications. Due to the lack of atmospheric absorption, devices operating within these spectral bands are particularly useful for spectroscopy, imaging, and dynamic scene projection. Advanced IR imaging systems have created an intense need for laboratory-based infrared scene projector (IRSP) systems which can be used for accurate simulation of real-world phenomena occurring in the IR. These IRSP systems allow for reliable, reproducible, safe, and cost-effective calibration of IR detector arrays. The current state-of-the-art technology utilized for the emitter source of IRSP systems is thermal pixel arrays (TPAs) which are based on thin film resistor technology. Thermal pixel array technology has fundamental limitations related to response time and maximum simulated apparent temperature, making them unsuitable for emulation of very hot (> 700 K) and rapidly evolving scenes. Additionally, there exists a need for dual wavelength emitter arrays for IRSP systems dedicated to calibration of dual wavelength detector arrays. This need is currently met by combining the spectral output from two separate IRSP systems. This configuration requires precise alignment of the output from both systems and results in the maximum radiance being limited to approximately half that of the capability of a given emitter array due to the optics used to combine the outputs. The high switching speed inherent to IR light-emitting diodes (LEDs) and the potential for high power output makes them an appealing candidate to replace the thermal pixel arrays used for IRSP systems. To this end, research has been carried out to develop and improve the device performance of IR LEDs based on InAs/GaSb type-II superlattices (T2SLs). A common method employed to achieve high brightness from LEDs is to incorporate multiple active regions, coupled by tunnel junctions. Tunnel junctions must provide adequate barriers to prevent carrier leakage, while at the same time remain low in tunneling resistance to prevent unwanted heating. The performance of two tunnel junction designs are compared in otherwise identical four stage InAs/GaSb superlattice LED (SLED) devices for application in IRSP systems. This research culminated in the development of a 48 Μm pitch, 512$times512 individually addressable mid-wave IR LED array based on a sixteen stage, InAs/GaSb T2SL device design. This array was hybridized to a read-in integrated circuit and exhibited a pixel yield greater than 95 %. Projections based on single element emitter results predict this array will be able to achieve a peak apparent temperature of 1350 K within the entire 3-5 Μm band. These results demonstrate the feasibility of emitter arrays intended for IRSP systems based on InAs/GaSb SLED devices. Additionally, a dual wavelength 48 Μm pitch, 8x8 emitter array based on InAs/GaSb T2SL LEDs was developed and demonstrated. This design incorporates two separate, 16 stage InAs/GaSb SL active regions with varying InAs layer thicknesses built into a single vertical heterostructure. The device architecture is a three terminal device allowing for independent control of the intensity of each emission region. Each emitter region creates a contiguous pixel, capable of being planarized and mated to drive electronics.

This dissertation models K-12 enrollment within an urban school district using two grade progression ratio (gpr)-based and two housing choice methods. The housing choice methods provide, for the first time, a new spatio-demographic model for projecting school enrollments by grade for any flexibly defined set of individual catchment areas. All methods use the geocoded pattern of individual, address-matched, enrollments within the study district but are different in the way they model this data to estimate key parameters. The conventional method projects the intra-urban pattern of enrollment by assuming no change in grade progression ratios (gprs), which are themselves functions of enrollment change. The adaptive kernel ratio estimation (KRE) of local gprs successfully predicts local changes in gprs from three preceding two-year periods of gpr change. The two housing choice methods are based on different mixtures of a generalized linear and a periodic model, each of which use housing counts and characteristics. Results are clearly sensitive to these differences. Using the above predictions of gpr change, the adaptive KRE enrollment projections are 4.1% better than those made using the conventional model. The two housing choice models were 2.0% less accurate than the conventional model for the first three years of the projection but were 5.1% more accurate than this model for the fourth and fifth years of the projection. Limitations are discussed. These findings help close a major gap in the literature of small-area enrollment projections, shed new light on spatial dynamics collected at areas below the scale of the school district, and permit new kinds of investigations of urban/suburban school district demography.

A visual investigation into the lighting, scenic and projection design work of Lucas P. Ingram during his training at the University of Iowa from 2013 – 2016.

This thesis outlines the development of a mathematical model which can be used to perform 3D reconstruction of a target object from surveillance images. 3D reconstruction is a common procedure in photogrammetry, but performing 3D reconstruction from surveillance images can be more difficult than typical photogrammetry applications. Surveillance images are generally captured in an unsystematic manner because there is no control over the target that is being photographed. Surveillance images can have a wide variety of fields of view, are often captured with uncalibrated cameras, and typically the targets are objects for which there is no other a priori information. For these reasons, performing 3D reconstruction from surveillance images may not be possible using standard photogrammetric methods, especially when the angular fields of view of the images are rather narrow.

The NASA Airborne Topographic Mapper (ATM) is a laser scanning instrument which is used mainly to collect dense topographic data over much of the conterminous US coastline. The inclusion of two digital cameras in consonance with the ATM instrument now gives 3-band (RGB) imagery apart from a very rich topographic data. This imagery, in its crude form, has limited applications due to it being not georeferenced and having a heavy camera lens distortions. As thesis, a processing system - Park-View - is developed to bring this imagery into a more suitable format for the scientists for analytical and interpretational purposes. Park-View utilizes the well gridded elevation data from layer four of another processing system called LaserMap for georeferencing the digital camera images. Camera lens behavior is modeled using a 2D grid image and all of its intrinsic parameters ascertained. These parameters are then incorporated into correcting the lens distortions of georeferenced images. Errors in time-stamping of images and in the mounting angles of the camera are calculated using well known tie-points. Georeferenced images can be stored either in GeoTiff format or jpeg format. Individual images can be georeferenced or put in a mosaic form with the mosaic color equalized for adjoining images. Park-View also provides the main GUI displaying the entire surveyed area, mapper GUI for a batch processing of all the images and a display window for displaying georeferenced images or mosaics. Additional capabilities could be added to the processing system for performing some specific image processing operations on the images such as edge detection and image enhancement.