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Ryder, Justin. "Three-dimensional Body Scanning| A Novel Technique for Body Composition Assessment." Thesis, University of Missouri - Columbia, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13850748.
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INTRODUCTION: Accurate body composition assessment is crucial for determining health consequences due to excess body fat (BF). While several techniques exist there are few that are accurate, non-invasive, fast, and comfortable for subjects. The Three Dimensional (3D) body scanner is a new body composition assessment method that might serve as another option for investigators and practitioners. The purpose of this study was to determine the accuracy of the 3D body scanner at measuring body composition using dual energy x-ray absorptiometry (DXA) and Air displacement plethysmography (Bod Pod) as criterion measures. The 3D body scanner was evaluated on its ability to work with differences in normal versus overweight subjects as determined by BMI. Also, a new prediction equation was created and compared to that of an existing equation used by the 3D body scanner developed by the Department of Defense (DoD).
METHODS: Eighty-Five male subjects (21.70 ± 2.28 yr old; 81.00 ± 12.21 kg; 25.37 ± 3.40 kg/m2) completed all body composition assessment techniques on the same day. Tests preformed included: DXA, Bod Pod, and 3D body scanning. Subjects did not eat or drink 2 hr previous to testing and did not exercise 4 hr previous to testing. Data was analyzed using SPSS version 17.0. Bland-Altmand plots, Pearson correlations, and a oneway ANOVA comparing means were performed. A prediction equation (3D MU) was created using a stepwise regression based on correlation to DXA.
RESULTS: Mean comparison of body composition techniques were as follows: DXA BF 16.30 ± 4.67; Bod Pod 12.17± 7.19; DoD 13.53 ± 6.43; 3D MU 16.49 ± 4.16. 3D MU had a SEE=3.09 over the entire sample compared to DoD SEE=3.67 and Bod Pod SEE=2.45. Although body volumes of Bod Pod and 3D Scanner were highly correlated (r = 0.984; p =0.001), the 3D Scanner underestimated body volume. Improvement in making consistent estimations of head, hand, and feet are necessary for the 3D body scanner to be used for body composition assessment.
CONCLUSION: Although the 3D body scanner shows promise as a method of evaluating BF, more work is needed before it can be considered an acceptable laboratory method of assessment. A 3D MU prediction equation was created that appears to be more accurate for young men than the current DoD equation. 3D body scanning shows potential as a method for determining body composition in overweight subjects.
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Chiu, Chuang-Yuan. "Rapid three-dimensional photonic scanning system for body volume measurement and body shape visualization." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/22003.
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Traditional three-dimensional (3D) photonic scanning (3DPS) can be used to obtain body volume data and to enable visualization of 3D body shape in one rapid scan, which is helpful for determining people’s obesity level, health risk and sport performance as well as motivating individuals to reduce weight efficiently. Nevertheless, traditional 3DPS is restricted to expensive and fixed hardware and specific software that requires specialist interpretation in laboratory settings, which reduces possible applications. Therefore, the purpose of this research was to develop a fast, inexpensive, portable and automatic 3DPS system to measure body volume data and to display body shape in 3D. To ensure that the system could be used for monitoring changes over time, the accuracy and reliability of the estimated body volumes were also established. Four studies and one technical description were conducted to achieve the purpose of this research. In the first three studies, a new technique, DScan, was developed that could generate individual 3D human models and calculate body volume. In Study 1, the reliability of the body dimension features obtained by four extraction methods was compared to find an appropriate method to improve the quality of extracted body dimension features. In Study 2, two different parameter groups were compared to enable subsequent selection of appropriate parameters to generate realistic 3D human models. A procedure and a program were presented which can set the parameters to match the extracted features and generate individual 3D human models effectively. In Study 3, Blender scripts and shell scripts were used to develop a customized program which can obtain body volume data from generated 3D human models. In Study 4, the accuracy and the reliability of the body volume data acquired from DScan were examined by comparing with the traditional 3DPS and the geometric modelling technique, elliptical zone (E-Zone). In the technical description, a Body Shape Monitoring System (BSMS) which can help non-expert users complete the DScan procedure and visualize body shape changes was introduced. The processing speed, cost and portability of the introduced BSMS were also shown in the technical description. The accuracy of the BSMS for whole-body volume indicated by an inter-method relative technical error of measurement was within 5% of that obtained from the traditional 3DPS. The repeated reliability expressed as an intra-method relative technical error of measurement was under 3% for whole-body volume. The accuracy and the reliability of the BSMS for segmental volumes (upper torso, lower torso, upper arm, lower arm, thigh and shank) indicated by inter-method and intra-method relative technical error of measurements were less than 10% and 5% respectively. These were similar to those obtained by the E-Zone. The BSMS reduces the requirement of hardware, software and expert knowledge as well as the processing time compared to other techniques of quantifying whole-body volume and segmental volumes. The GUI of the BSMS enables it to be used without specific training in computer programing or machine operation. The system is highly portable, and its components are inexpensive (under £700). Each analysis can be completed in three minutes without requiring subjective interpretations. The results showed that the system has the potential to be applied in the domains of health and medicine, the fashion industry, ergonomics, and sports science. Further studies should be conducted to develop a complete system which is consequently suitable for home use.
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Simão, Bruno Rodrigo. "Determinação de área, volume e massa em animais de interesse zootécnico." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/152324.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A fim de utilizar a modelagem tridimensional (3D) para estimar área, volume e massa, bem como avaliar o impacto dos desvios envolvidos nas equações empíricas disponíveis na literatura, em animais, foram utilizados seis ovinos Corriedale tosqueados com massa entre 10 e 105 kg e cinco bovinos Nelore com massa entre 600 a 800 kg. Os animais foram treinados utilizando os princípios de habituação e condicionamento, a fim de reduzir a reatividade dos animais. Para medição da área de superfície, utilizaram-se basicamente três procedimentos: equação empírica (EE) para cada espécie, instrumento manual de medição (IMM) e modelagem 3D do animal por fotogrametria (AR) e escaneamento com sensor kinect (AS_KS). Foi realizada uma análise de covariância, sendo a massa a covariável e uma análise de regressão não linear foi ajustada como uma função potência (alometria). Analisando as médias de área de superfície, para ovinos, em relação aos procedimentos utilizados não houve diferença entre IMM e modelos 3D, bem como entre os modelos 3D, enquanto entre IMM e EE houve diferença significativa. Para os bovinos, observou-se que os procedimentos 3D foram, em média, superiores às estimativas de área de superfície pela EE (a=5%). Quando se plotou os dados de área de superfície, de ovinos, dos métodos testados em função da massa corporal, obteve-se aproximações empíricas distintas daquelas estimadas pela EE em mais de 11% para animais acima de 100kg, enquanto que para os bovinos a diferença média entre os modelos 3D e EE foi de mais de 18%. Como os ajustes das equações com IMM e por modelos 3D tiveram taxas de crescimento muito próximas e os desvios entre elas foram inferiores a 2%, constatou-se que o uso de modelos 3D foi ratificado. Quando se plotou os dados de ambas as espécies, observou-se excelentes ajustes (R²=0.99) e estimativas consistentes com aquelas obtidas pelas equações específicas para cada raça, com desvios inferiores a 3,2%. Outras relações, como volume em função da área de superfície, foram estabelecidas, resultando em aproximações consistentes quando utilizada para estimar o volume do animal. Quando se considerou o animal como um Cilindro Horizontal Padrão (CHP), sua área de superfície foi estimada, em média, 36% abaixo daquelas observadas para os modelos 3D e IMM. Por meio da simulação da transferência de calor por convecção, obteve-se uma diferença de mais 56% na taxa de convecção quando se considerou o animal como um CHP em relação aos modelos 3D e cilindro horizontal completo (CHC). Quando se relacionou as informações das imagens bidimensionais (2D) com as informações dos modelos 3D, foi possível encontrar equações para estimar área, volume e massa dos animais. Outra abordagem que ficou constatada foi a utilização de modelos 3D para avaliação em melhoramento genético, como pelo método EPMURAS. O uso de modelos 3D para estimar a área de superfície e volume em animais foi validado. O método parece ser o melhor meio para estimar a área de superfície e volume, e certamente aparece como uma ferramenta para melhorar as pesquisas envolvendo transferência de calor e massa, bem como o melhoramento genético.
In order to use three-dimensional (3D) modeling to estimate area, volume and mass, as well as to evaluate the impact of the deviations involved in the empirical equations available in the literature, in livestock, six shorn Corriedale sheep were weighed with mass between 10 and 105 kg and five Nelore cattle with mass between 600 and 800 kg. The animals were trained using the principles of habituation and conditioning in order to reduce the reactivity of the animals. For the measurement of the surface area, three procedures were used: empirical equation (EE) for each species, manual measurement instrument (IMM) and 3D animal modeling by photogrammetry (AR) and kinect sensor (AS_KS) scanning. A covariance analysis was performed, with the mass being covariable and a non-linear regression analysis was adjusted as a power function (allometry). Analyzing the surface area averages for sheep, in relation to the procedures used there was no difference between IMM and 3D models, as well as between 3D models, while between IMM and EE there was a significant difference. For cattle, it was observed that the 3D procedures were, on average, higher than the surface area estimates by EE (a=5%). When data were plotted on the surface area of sheep and the methods tested for body mass, empirical approximations were obtained, different from those estimated by EE in more than 11% for animals over 100 kg, while for cattle the difference between 3D and EE models was over 18%. As the adjustments of the equations with IMM and 3D models had very close growth rates and deviations between them were lower than 2%, it was verified that the use of 3D models was ratified. When plotting the data of both species, we observed excellent adjustments (R² = 0.99) and estimates consistent with those obtained by the specific equations for each breed, with deviations lower than 3.2%. Other relationships, such as volume versus surface area, were established, resulting in consistent approximations when used to estimate the volume of the animal. When the animal was considered as a Standard Horizontal Cylinder (CHP), its surface area was estimated, on average, 36% lower than those observed for the 3D and IMM models. Simulation of the heat transfer by convection gave a difference of 56% in the convection rate when the animal was considered as a CHP in relation to the 3D models and the full horizontal cylinder (HCC). When the information of the two-dimensional images (2D) was related to the information of the 3D models, it was possible to find equations to estimate area, volume and mass of the animals. Another approach that was verified was the use of 3D models for evaluation in genetic improvement, as by the EPMURAS method. The use of 3D models to estimate surface area and volume in animals was validated. The method seems to be the best medium for estimating surface area and volume, and it certainly appears as a tool to improve research involving heat and mass transfer as well as genetic improvement.
CAPES 1367458
CAPES 1443570
CAPES 1707637
CNPq 166449/2017-2
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Sabo, Stanislav. "Tvorba 3D modelu budovy s využitím laserového skenování." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-390227.
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The aim of this thesis is to scan the part of the interior and exterior of the Faculty of Electrical Engineering and Communication building using the FARO Focus3D X 130 scanner, and the creation of a 3D model in the WGS 84 system. Subsequently, methods, status and utilization research of this technology and point cloud processing software is provided. The collected data are processed in the SCENE. Three-dimensional model is designed using the Pointfuse and Microstation V8i programs. In the end, the registration accuracy of the scans and the resulting 3D model accuracy are evaluated.
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Schilling, Bradley Wade Jr. "Three-Dimensional Fluorescence Microscopy by Optical Scanning Holography." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/29829.
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As three-dimensional (3D) imaging and fluorescence techniques become standard in optical microscopy, novel approaches to 3D fluorescence microscopy are emerging. One such approach is based on the incoherent holography technique called optical scanning holography (OSH). The main advantage of OSH-based microscopy is that only a single two-dimensional (2D) scan is required to record 3D information, whereas most current 3D microscopes rely on sectioning techniques. To acquire a 3D representation of an object, current microscopes must physically scan the specimen in a series of 2D sections along the z-axis.
In order to record holograms by OSH, the fluorescent specimen is scanned with an optically heterodyned laser field consisting of a Fresnel zone pattern. A unique acousto-optic modulator configuration is employed to generate a suitable heterodyne frequency for excitation of the fluorescent object. The optical response of a solution containing a high concentration of 15 um fluorescent latex beads to this type of excitation field has been recorded. In addition, holograms of the same beads have been recorded and reconstructed. To demonstrate the 3D imaging capability of the technique, the hologram includes beads with longitudinal separation of about 2 mm.
A detailed comparison of 3D fluorescence microscopy by OSH and the confocal approach was conducted. Areas for comparison were 3D image acquisition time, resolution limits and photobleaching. The analysis shows that an optimized OSH-based fluorescence microscope can offer improved image acquisition time with equal lateral resolution, but with degraded longitudinal resolution when compared to confocal scanning optical microscopy (CSOM). For the photobleaching investigation, the parameter of concern is the fluence received by the specimen during excitation, which takes into account both the irradiance level and the time of illumination. Both peak and average fluence levels are addressed in the comparison. The analysis shows that during a 3D image acquisition, the OSH system will deliver lower peak fluence but higher average fluence levels to the specimen when compared to CSOM.Ph. D.
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Javid, Shawn Farhang. "Three-dimensional image processing using voxels." Thesis, University College London (University of London), 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312149.
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Honiball, Marike. "Three-dimensional scanning as a means of archiving sculptures." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2011. http://hdl.handle.net/11462/149.
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Thesis (M. Tech. Design technology) -- Central University of Technology, Free State, 2011This dissertation outlines a procedural scanning process using the portable ZCorporation ZScanner® 700 and provides an overview of the developments surrounding 3D scanning technologies; specifically their application for archiving Cultural Heritage sites and projects. The procedural scanning process is structured around the identification of 3D data recording variables applicable to the digital archiving of an art museum’s collection of sculptures. The outlining of a procedural 3D scanning environment supports the developing technology of 3D digital archiving in view of artefact preservation and interactive digital accessibility. Presented in this paper are several case studies that record 3D scanning variables such as texture, scale, surface detail, light and data conversion applicable to varied sculptural surfaces and form. Emphasis is placed on the procedural documentation and the anomalies associated with the physical object, equipment used, and the scanning environment. In support of the above, the Cultural Heritage projects that are analyzed prove that 3D portable scanning could provide digital longevity and access to previously inaccessible arenas for a diverse range of digital data archiving infrastructures. The development of 3D data acquisition via scanning, CAD modelling and 2D to 3D data file conversion technologies as well as the aesthetic effect and standards of digital archiving in terms of the artwork – viewer relationship and international practices or criterions of 3D digitizing are analysed. These projects indicate the significant use of optical 3D scanning techniques and their employ on renowned historical artefacts thus emphasizing their importance, safety and effectiveness. The aim with this research is to establish that the innovation and future implications of 3D scanning could be instrumental to future technological advancement in an interdisciplinary capacity to further data capture and processing in various Cultural Heritage diagnostic applications.
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Redpath, Steven F. "Crack detection in a three dimensional body." Diss., Click here for available full-text of this thesis, 2006. http://library.wichita.edu/digitallibrary/etd/2006/t072.pdf.
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Brown, William Ray. "A three-dimensional quantitative biomechanical analysis of left handed scanning." [Ames, Iowa : Iowa State University], 2007.
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Khmaladze, Alexander. "Three-dimensional microscopy by laser scanning and multi-wavelength digital holography." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002638.
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McVey, Alexander Ferguson. "Three-dimensional imaging of bacterial microcolonies." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/15774.
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Previous research into microbial colonies and biofilms shows a significant gap in our current understanding of how bacterial structures develop. Despite the huge body of research undertaken into the formation, genetic makeup, composition, and optimal growth conditions of colonies, no study has been successful in identifying all individual bacteria in a colony in three-dimensions as a function of time. This lack of bacterial cell lineage in such a simple class of organisms is conspicuous in the light of what is known about other organisms, such as Caenorhabditis elegans [1]. In this thesis I show that using laser scanning confocal microscopy in conjunction with developments in sample preparation and post acquisition image analysis, it is possible to fully reconstruct all individual bacteria within an Escherichia coli (E. coli ) microcolony grown in viscoelastic media. Additionally, I show that by further pushing the resolution of confocal microscopes, commercial systems are capable of extracting three-dimensional information on protein structures inside bacteria at early stages of growth. This thesis is in three parts. The first part shows that by pushing the resolution of a commercial laser scanning confocal microscope system it is possible to achieve single cell resolution of a bacterial colony growing in three dimensions in a viscoelastic medium (agarose) from a seed bacterium. The growth of individual bacteria is examined as the concentration of agarose in the media is altered. Results show there is a nonlinear dependence between the rate of growth of a bacterium and the concentration of the agarose in the media with a peak in growth rate at 3% (weight) concentrations of agarose in M9 media. The second part of this work presents a study of how an initially two-dimensional colony growing between a glass slide and agarose gel suddenly invades the third spatial dimension by buckling. The results show that the cells within the centre of the colony flex and buckle, due to confinement by their neighbours, creating additional layers. Indeed, flexing is not limited to the buckling event but occurs throughout the early growth cycle of a colony. The final part of this thesis shows that by further pushing the resolution of confocal microscopes, commercial systems are capable of extracting three-dimensional information about the temporal evolution of the spatial distribution of the FtsZ septation ring within the cell. As the bacterial colony grows from a seed bacterium to a microcolony, the error in placing the division accurately at the cell centre is seen to increase as the number of bacteria within the colony increases and spatial confinement occurs.
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Liu, Hang. "Studies of the Nuclear Three-Body System with Three Dimensional Faddeev Calculations." Ohio University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1127332785.
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Yan, Hongmei. "Computations of fully nonlinear three-dimensional wave-body interactions." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61616.
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Thesis (Ph. D. in Ocean Engineering)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references.
Nonlinear effects in hydrodynamics of wave-body interaction problems become critically important when large-amplitude body motions and/or extreme surface waves are involved. Accurate prediction and understanding of these fully nonlinear effects are still challenges in the design of surface ships and marine structures, owing to the complexity of the hydrodynamic problem itself and limited computational facilities. This research is focused on: (i) development of a highly efficient numerical scheme for the computation of fully-nonlinear three-dimensional wave-body interactions; and (ii) investigation of several highly nonlinear wave-body interaction problems for understanding associated key nonlinear effects. A highly efficient high-order boundary element method is developed based on the framework of the quadratic boundary element method (QBEM) for the boundary integral equation and using the pre-corrected fast Fourier transform (PFFT) algorithm to accelerate the evaluation of far-field influences of source and/or normal dipole distributions on boundary elements. The resulting numerical scheme reduces the computational effort of solving the boundary-value problem from O(N 2 ~3) (with the traditional boundary element methods) to O(N ln N) where N represents the total number of boundary unknowns. Combining with the mixed-Eulerian-Lagrangian (MEL) approach for nonlinear free surface tracking, we develop an efficient and accurate initial boundary value problem (IBVP) solver, PFFT-QBEM, which allows for practical simulations of fully nonlinear three-dimensional wave-body interaction problems. Three nonlinear wave-body interaction problems, which are of scientific interest and practical importance, are investigated in detail: water surface impact of threedimensional objects, cavity dynamics in water entries, and coupled unstable motions of floating structures in waves. For the water impact problem, with the development of an adaptive jet flow treatment and an effective approach for accurately tracking water-body separation point/line, we obtain a thorough understanding of the gravity effect on the characteristics of slamming pressure/load on the object and free-surface profiles. For the cavity problem, we investigate the formation and evolution of an air cavity behind an object dropped into water (from air) at relatively low Froude numbers where the inertia and gravity effects are comparable. A theoretical solution is newly derived based on a matched asymptotic approach and a fully nonlinear numerical simulation is carried out, for the description of the kinematics and dynamics of the air cavity. Satisfactory quantitative comparisons are obtained among the theoretical predictions, numerical simulations, and existing experimental measurements for the dependence of cavity shape and closure time/height on Froude number and body geometry. For floating structures in waves, our focus is on the understanding of the fundamental mechanism and basic characteristics for coupled unstable heave-pitch motions of floating platforms/vessels. Through stability analyses, we identify that the second-order difference-frequency interaction between surface waves and body motions is the key mechanism for the excitation of unstable resonant motions. Fully nonlinear simulations are conducted to study the development of large-amplitude body motions and investigate quantitatively the dependence of the instability on related physical parameters, such as incident wave amplitude and phase, frequency detuning, body geometry, and system damping. Theoretical analyses and numerical simulations are verified by comparison to available experiments for the coupled unstable motions of a deep draft caisson vessel (DDCV).
by Hongmei Yan.
Ph.D.in Ocean Engineering
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Zhang, Xin, and 张鑫. "Sectional image reconstruction in optical scanning holography." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B4476487X.
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Majola, Khwezi. "Three-Dimensional Body Volume Measurement From Two-Dimensional Images: Towards A Smartphone Application." Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/32797.
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Obesity poses a public health threat worldwide and is associated with a higher mortality, increased likelihood of diabetes, and an increased risk of cancer. When treating obesity, regular monitoring of metrics such as body mass index (BMI) and waist circumference has been found to result in improved health outcomes for patients. Three-dimensional (3D) scanners provide a useful tool to provide body measurements based on 3D images in obesity management. However, such scanners are often inaccessible due to cost. A smartphone image-based method able to produce 3D images may provide a more accessible measuring tool. As a step towards developing such a smartphone application, this project developed a method for 3D reconstruction of body images from two-dimensional (2D) images, using a full body 3D Gaussian process morphable model (GPMM). Separate GPMMs were trained to learn the shape of female and male human bodies. Gaussian process regression of the three-dimensional (3D) GPMM models onto two-dimensional (2D) images is performed. Corresponding landmarks on the 3D shapes and in the 2D images are employed in reconstruction. Measurements of body volume, waist circumference and height are then performed to extract information that is useful in obesity management. Different model configurations (shape model with arms; modified shape model with arms; shape model without arms; marginalised shape model without arms; shape model with different landmarks) were used to ascertain the most promising approach for the reconstruction. Each reconstructed body was tested for accuracy using the surface-tosurface distance per vertex, modified Hausdorff distance, and assessment of the measurements. Tests were performed using data from the same dataset used to build the model and generalised data from a different dataset. In all test cases, the best performing approach used shape models without arms when considering surface distances. However, the surface-to-surface distances errors were larger than those seen in literature. For body measurements, the best performing models varied with different models performing best for different measurements. For the measurements, the errors were larger than the allowable errors and larger than those found in literature. Landmark positions were evaluated separately and found to be imprecise. There are a few sources that contribute towards the reconstruction errors. Possible sources of error include an inability to interpret pose and landmark position errors. The major recommendations for future work are to use a model that incorporates both shape and pose and to use automatic landmarking methods. Regarding a pathway to a smartphone app, camera parameter information should be considered to improve processing of the images and smartphone orientation information should be considered to correct for distortions due to a tilted phone.
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Smith, Nicholas E. "Acquiring three-dimensional data from small mammalian teeth laser scanning Eocene marsupials /." Huntington, WV : [Marshall University Libraries], 2007. http://www.marshall.edu/etd/descript.asp?ref=779.
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Cosgriff, Eireann Catherine. "Image formation mechanisms in three-dimensional aberration-corrected scanning transmission electron microscopy." Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:e7ddeaf7-4d16-47d3-9248-3b2cfa7d0a6b.
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This thesis considers the theory and calculations of image formation mechanisms for various modes of three-dimensional imaging in aberration-corrected scanning transmission electron microscopy. Discrete tomography is used to determine and refine the three-dimensional structure of molecular nanowire bundles. The structure determination is expedited by the use of annular dark-field imaging, an incoherent imaging mode which provides directly interpretable images. The development of spherical aberration correctors and the subsequent reduction in probe sizes, including the depth of field, has made optical depth sectioning a feasible technique. The localisation in three dimensions of substitutional impurity atoms in zone-axis imaging is discussed. Both the channelling of the probe and the pre-focussing effect of the atomic column play an important role in determining the depth response of the impurity atom. Interband scattering within a sample is shown to be influential in imaging crystals containing dislocations and optical depth sectioning is explored as a possible option for overcoming surface relaxation effects in the imaging of screw dislocations end-on. The possibility of extending the optical depth sectioning approach using aberration-corrected scanning confocal electron microscopy is discussed. The coherent and incoherent imaging modes, involving elastically and inelastically scattered electrons respectively, are investigated.
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Worasawate, Denchai. "Electromagnetic scattering from an arbitrarily shaped three-dimensional chiral body." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2002. http://wwwlib.umi.com/cr/syr/main.
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Stewart, Gregory B. "A computer based method to record three-dimensional body postures." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-02132009-171127/.
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Tombazis, Nicholas. "Effects of three-dimensional disturbances on bluff body near wakes." Thesis, Imperial College London, 1993. http://hdl.handle.net/10044/1/61139.
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The three-dimensionality of the near wake of bluff bodies at high Reynolds numbers is studied experimentally. Measurements were carried out in a 0.9Imx 0.91m wind tunnel (for Re=20000 to 60000) and flow visualisation in a 0.6mx 0.6m water flume (for Re=25(X)). The main purpose is to identify inherent three-dimensional features that may also arise in nominally two-dimensional flows. In order to fix the three-dimensional effects in both time and space, a mild, periodic, geometrical disturbance was imposed on the otherwise two-dimensional geometry of a model with a blunt trailing edge. The trailing edge thus followed a sinusoidal pattern, but a straight edge model was also studied for comparison purposes. Quantitative measurements and flow visualisation revealed that a dual shedding frequency characteristic prevails in the wake of the sinusoidal model. Base drag shows a noticeable drop (in comparison to the straight edge model). Most of the activity seems to happen in the region of the peak, where the dual frequency characteristic is more apparent and also the base drag shows its largest variations. Flow visualisation showed different modes of vortex shedding to exist. Vortical structures in the x- and z- directions were observed for both models. Og vortices are present in the near wake. It is believed that the observed vortices are responsible for the intense base pressure fluctuations and gradients, and also for thin "wisps" appearing between Karman vortices in flow visualisation. A model for the dynamics of the formation region is proposed, by considering the interaction of mean, time-averaged quantities. It is suggested that forming vortices have a tendency to straighten-out. A concept is proposed which links the vortex formation length to other wake parameters, most notably wake width and base pressure. Wake similarity arguments are used in order to explain the shedding frequency variations along the span. The dynamics of vortex dislocations are also discussed. A mechanism is proposed which explains the significance of a characteristic dislocation frequency, fd in the near wake dynamics. It is suggested that fd is a result of the geometrical properties of the vortex filaments and that a link exists between the dislocation frequency and fluctuations in base pressure, vortex strengths and spanwise dislocation position.
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Grierson, Yvonne Martha. "A three-dimensional whole body model for dynamic motion analysis." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/12768.
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Zhao, Feng. "An O̳(N̳) algorithm for three-dimensional N̳-body simulations." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14717.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1988.Double underscored characters appear as italic on title page.
Bibliography: leaves 130- 131.
by Feng Zhao.
M.S.
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Kim, Taegeun. "Optical Three-Dimensional Image Matching Using Holographic Information." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/28362.
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We present a three-dimensional (3-D) optical image matching technique and location extraction techniques of matched 3-D objects for optical pattern recognition. We first describe the 3-D matching technique based on two-pupil optical heterodyne scanning. A hologram of the 3-D reference object is first created and then represented as one pupil function with the other pupil function being a delta function. The superposition of each beam modulated by the two pupils generates a scanning beam pattern. This beam pattern scans the 3-D target object to be recognized. The output of the scanning system gives out the 2-D correlation of the hologram of the reference object and that of the target object. When the 3-D image of the target object is matched with that of the reference object, the output of the system generates a strong correlation peak. This theory of 3-D holographic matching is analyzed in terms of two-pupil optical scanning. Computer simulation and optical experiment results are presented to reinforce the developed theory.
The second part of the research concerns the extraction of the location of a 3-D image matched object. The proposed system basically performs a correlation of the hologram of a 3-D reference object and that of a 3-D target object, and hence 3-D matching is possible. However, the system does not give out the depth location of matched 3-D target objects directly because the correlation of holograms is a 2-D correlation and hence not 3-D shift invariant. We propose two methods to extract the location of matched 3-D objects directly from the correlation output of the system. One method is to use the optical system that focuses the output correlation pattern along depth and arrives at the 3-D location at the focused location. However, this technique has a drawback in that only the location of 3-D targets that are farther away from the 3-D reference object can be extracted. Thus, in this research, we propose another method in which the extraction of a location for a matched 3-D object is possible without the aforementioned drawback. This method applies the Wigner distribution to the power fringe-adjusted filtered correlation output to extract the 3-D location of a matched object. We analyze the proposed method and present computer simulation and optical experiment results.Ph. D.
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Hasanovic, Moamer. "Electromagnetic scattering from an arbitrarily shaped three-dimensional inhomogeneous chiral body." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2006. http://proquest.umi.com/login?COPT=REJTPTU0NWQmSU5UPTAmVkVSPTI=&clientId=3739.
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Chapman, D. A. "Theory for three dimensional dynamic simulation of towed cable-body systems." Thesis, University of Bath, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378147.
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Mei, Chong. "Electromagnetic scattering from an arbitrarily shaped three dimensional inhomogeneous bianisotropic body." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2007. http://wwwlib.umi.com/cr/syr/main.
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Xue, Ming 1967. "Three-dimensional fully-nonlinear simulations of waves and wave body interactions." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10216.
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Reichstein, Georg A. "Estimation of axial compressor body forces using three-dimensional flow computations." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/47806.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2009.Includes bibliographical references (p. 77-78).
This thesis presents an examination of body force distributions in a single stage low speed compressor. The body force distributions are developed using two different computational procedures, an axisymmetric streamline curvature calculation and an unsteady, three-dimensional flow simulation. A two-dimensional body force representation is defined as a benchmark to evaluate the departures of the computed forces from two-dimensional behavior. The most important contribution to this departure (for both the streamline curvature calculation and the three-dimensional simulation) is identified as the change in streamtube height across the blade rows. The magnitude of the departures increase with blade loading and, for the compressor examined, are smaller than five per cent of the two-dimensional estimate at design but show values up to 50 per cent near stall.
by Georg A. Reichstein.
S.M.
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Bellotti, Filipe Furlan. "Two- and three- dimensional few-body systems in the universal regime." Instituto Tecnológico de Aeronáutica, 2014. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=3074.
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Macro properties of cold atomic gases are driven by few-body correlations, even if the gas has thousands of particles. Quantum systems composed of two and three particles with attractive zero-range pairwise interactions are considered for general masses and interaction strengths in two and three dimensions (2D and 3D). The Faddeev decomposition is used to derive the equations for the bound state, which is the starting point for the investigation of universal properties of few-body systems, i.e. those that all potentials with the same physics at low energy are able to describe in a model-independent form. In 2D, the number of bound states in a three-body system increases without bound as the mass of one particle becomes much lighter than the other two. The analytic form of an effective potential between the heavy particles explains the mass-dependence on the number of bound energy levels. An exact analytic expression for the large-momentum asymptotic behavior of the spectator function in the Faddeev equation is presented. The spectator function and its asymptotic form define the two- and three-body contact parameters. The two-body parameter is found to be independent of the quantum state in some specific 2D systems. The 2D and 3D momentum distributions have a distinct sub-leading form whereas the 3D term depends on the mass of the particles. A model that interpolates between 2D and 3D is proposed and a sharp transition in the energy spectrum of three-body systems is found.
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Schurch, Brandt Roger. "Three-dimensional imaging and analysis of electrical trees." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/threedimensional-imaging-and-analysis-of-electrical-trees(73e032f6-3e6b-4ee9-9cc1-953a11f36cb3).html.
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Electrical trees are micrometre-size tubular channels of degradation in high voltage polymeric insulation, a precursor to failure of electrical power plant. Hence, electrical trees critically affect the reliability of power systems and the performance of new insulation designs. Imaging laboratory-grown electrical trees has been an important tool for studying how trees develop. Commonly, electrical trees prepared in transparent or translucent polymers are imaged using traditional optical methods. Consequently, most of the analysis has been based on two-dimensional (2D) images of trees, thus, valuable information may be lost. However, electrical trees are complex interconnected structures that require a tree-dimensional (3D) approach for more complete analysis. This thesis investigates a method for imaging and analysis of electrical trees to characterise their 3D structure and provide a platform for further modelling. Laboratory created electrical trees were imaged using X-ray Computed Tomography (XCT) and Serial Block-Face Scanning Electron Microscopy (SBFSEM), 3D imaging techniques that provide sub-micrometre spatial resolution. Virtual replicas of the trees, which are the 3D geometrical models representing the real electrical trees, were generated and new indices to characterise the 3D structure of electrical trees were developed. These parameters were indicative of differences in tree growth and thus, they can be used to investigate patterns and classify the structure of electrical trees. The progression of the tree was analysed using cross-sections of the tree that are orthogonal to the growth: the number of tree channels and area covered by them were measured. The fractal dimension of the tree was calculated from the 3D model and from the 2D projections, the latter being lower for all the tree-type structures studied. Parameters from the skeleton of the tree such as number of nodes, segment length, tortuosity and branch angle were measured. Most of the mean segment lengths ranged 6-13 µm, which is in accordance to the 10µm proposed by various tree-growth models. The capabilities of XCT and SBFSEM imaging techniques were evaluated in their application to electrical trees. Bush and branch trees, including early-growth electrical trees (of length 20-40 µm), were analysed and compared using the comprehensive tool of visualisation and characterisation developed. A two-stage tree-growth experiment was conducted to analyse the progression and development of tree branches using XCT: tree channels after the second stage of growth were wider than after the first, while the fractal dimension remained the same. The capabilities of XCT and SBFSEM were tested for imaging electrical trees in optically-opaque materials such as micro and nano-filled epoxy compounds. The general structure of trees in epoxy filled up to 20 wt% micro-silica was observed using both techniques. The use of a virtual replica as the 3D geometrical model for the simulation of the electric field distribution using Finite Element Analysis (FEA) was preliminary explored. A combination of the imaging techniques is proposed for a more complete structural analysis of trees. It is believed that a great impact towards understanding electrical treeing will be achieved using the 3D technical platform developed in this thesis.
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Monshi, Nasrollah. "Three-dimensional librational dynamics and control of multi-body tethered satellite systems." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61311.
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The first analytical method that is used for the development of reel rate laws is the Liapunov's second method. In this work it is shown that the Hamiltonian can be used as a Liapunov function. A reel rate law is devised that stabilizes the in-plane and out-of-plane librations at the same time, for two-body systems. However, since the resulting motion has some deficiencies, this reel rate law is not extended to multi-body systems.For overcoming these deficiencies, two new reel rate laws are proposed and their performances are examined through the energy dissipation approach together with the averaging method. The resulting motions with all the reel rate laws, including the one from Liapunov approach, are limit cycle oscillations. The reel rate laws obtained from the energy dissipation approach perform efficient retrievals with sufficiently small out-of-plane limit cycle amplitudes. These reel rate laws are extended to multi-body systems. For multi-body systems a station-keeping stage is added that brings the system to a final desired configuration. An analysis on the effects of different parameters and gains on the resulting motion has also been performed. (Abstract shortened by UMI.)
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Brackston, Rowan. "Feedback control of three-dimensional bluff body wakes for efficient drag reduction." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/52406.
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The wakes of bluff bodies, such as automotive vehicles, exhibit complex behaviour due to three-dimensionality and high Reynolds numbers, and are furthermore responsible for significant aerodynamic drag. There are significant environmental and economic incentives for reducing drag, however practicalities limit the extent to which this can be achieved through changes to the vehicle shape. This motivates the use of active feedback control methods that modify the flow directly, without significant geometric changes. In this thesis we develop feedback control strategies for two generic three-dimensional bluff bodies, a bullet-shaped body and the widely used Ahmed body. After first applying an extremum-seeking controller to a pre-existing open-loop strategy, we then examine the control of specific coherent structures within the wakes. Two such structures understood to be related to the drag are the static symmetry breaking (SB) mode and the quasi-oscillatory vortex shedding. The former of these is observed as a large-scale asymmetry within the recirculating region. We find, through simultaneous surface pressure and wake velocity measurements, that both the SB mode and vortex shedding may be observed in real-time using practical pressure sensors. Through the use of forcing flaps, we further demonstrate that we are able to strongly interact with both these coherent structures. Statically deflected flaps also prove effective at drag reduction under cross-wind conditions. In order to guide feedback controller design, we develop stochastic models for each of the coherent structures, describing their dynamics and response to forcing. Controllers are then implemented, achieving an efficient drag reduction of 2% when suppressing the asymmetry of the SB mode. Vortex shedding control proved ineffective at drag reduction, despite the suppression of measured fluctuations around the frequency at which oscillations are observed.
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Hutchinson, Erin B. "Estimation of kinetics using a three-dimensional model of the human body." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/33499.
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Jones, Robert Stephen. "The one-dimensional three-body problem and selected waveguide problems : solutions of the two-dimensional Helmholtz equation /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487843688957746.
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Fagerström, Viktor. "Structure from Motion, a Cheaper Alternative for Three-Dimensional Modeling in Earth Science." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-352372.
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In this report, two methods for three-dimensional modeling are evaluated against each other. The first method is terrestrial laser scanning (LiDAR) that uses a laser beam to record the surrounding environment, and the second one is called Structure from Motion (SfM). The SfM technique works on the same bases as photogrammetry, which is that an object of interest is photographed from multiple angles with overlapping images and mutual points are identified and used to create a three- dimensional model. Since both the equipment and the software used to produce LiDAR models are very expensive the main thought of this project was to produce the SfM model using a cellphone camera and free open source software. The study was carried out in such a way that a “before and after” -model was generated of a small snowy mound to see how well the SfM method performed compared to the LiDAR method. The final result revealed that SfM method deviated with approximately 8mm from the LiDAR method. One of the main difficulties during this project was to correctly reference the models against exact coordinate, which also could have been one reason to why the two models differed the way they did. Taking into consideration the user-friendliness and the low cost of the SfM method, it is a very promising tool for earth science related field research.I denna rapport så kommer två metoder för att framställa tredimensionella modeller att jämföras mot varandra. Den ena metoden är markbunden laserscanning (LiDAR), vilket använder sig av en scanner som skickar ut en laserstråle som scannar av omgivningen. Den andra metoden använder en teknik som kallas för ”Structure-from- Motion” (SfM). SfMs grunder bygger på samma teknik som används inom fotogrammetri, vilket är att objektet av intresse fotograferas, med en vanlig kamera, med ett flertal överlappande bilder och gemensamma punkter i dessa bilder används för att producera en tredimensionell modell. Då både utrustning och programvaran för att producera laserscanningar är mycket kostsamma så är grundtanken med denna undersökning att endast använda en mobiltelefonkamera och gratis öppen källkod programvara för att producera SfM modellen. Själva undersökningen gick till på så sätt att en ”före och efter” modell skapades av en snöhög med båda teknikerna för att se hur bra SfM förhöll sig mot LiDAR metoden. Resultatet visade sig att SfM metoden avvek från LiDAR-resultatet med ungefär 8mm. En av de största svårigheterna med detta projekt var att korrekt referera modellerna till exakta koordinater, vilket även kan vara en av orsakerna till att modellerna inte korrelerade med varandra helt och hållet. Med tanke på användarvänligheten och kostnaden för SfM metoden så är detta ett mycket lovande verktyg för användning inom geovetenskap.
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Anicio, de Magalhaes Fabricio <1980>. "Three-dimensional joint kinematics of swimming using body-worn inertial and magnetic sensors." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6595/.
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Wearable inertial and magnetic measurements units (IMMU) are an important tool for underwater motion analysis because they are swimmer-centric, they require only simple measurement set-up and they provide the performance results very quickly. In order to estimate 3D joint kinematics during motion, protocols were developed to transpose the IMMU orientation estimation to a biomechanical model. The aim of the thesis was to validate a protocol originally propositioned to estimate the joint angles of the upper limbs during one-degree-of-freedom movements in dry settings and herein modified to perform 3D kinematics analysis of shoulders, elbows and wrists during swimming. Eight high-level swimmers were assessed in the laboratory by means of an IMMU while simulating the front crawl and breaststroke movements. A stereo-photogrammetric system (SPS) was used as reference. The joint angles (in degrees) of the shoulders (flexion-extension, abduction-adduction and internal-external rotation), the elbows (flexion-extension and pronation-supination), and the wrists (flexion-extension and radial-ulnar deviation) were estimated with the two systems and compared by means of root mean square errors (RMSE), relative RMSE, Pearson’s product-moment coefficient correlation (R) and coefficient of multiple correlation (CMC). Subsequently, the athletes were assessed during pool swimming trials through the IMMU. Considering both swim styles and all joint degrees of freedom modeled, the comparison between the IMMU and the SPS showed median values of RMSE lower than 8°, representing 10% of overall joint range of motion, high median values of CMC (0.97) and R (0.96). These findings suggest that the protocol accurately estimated the 3D orientation of the shoulders, elbows and wrists joint during swimming with accuracy adequate for the purposes of research. In conclusion, the proposed method to evaluate the 3D joint kinematics through IMMU was revealed to be a useful tool for both sport and clinical contexts.
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Chatelain, Philippe Leonard Anthony. "Contributions to the three-dimensional vortex element method and spinning bluff body flows /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-02012005-061553.
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Byczkowski, Tomasz. "A stereo-based system with inertial navigation for three dimensional scanning of outdoor objects and architecture." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28051.
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Three-dimensional scanning is a topic which, in recent years, has gained significant attention from several research fields, including industrial design, reverse engineering and prototyping (e.g., CAD), body imaging (e.g., fashion and health care), computer vision ( e.g., world mapping), entertainment (e.g., gaming, visual effects and animation), photo tourism, forensics and documentation of cultural artifacts. Currently, 3D scanning is an involved process that generally requires special hardware and procedures, and is therefore frequently limited to a laboratory environment. However, there is a world full of potential subjects to digitize, most of which cannot be relocated to a laboratory without considerable expense, or at all.
In this thesis, we introduce a 3D scanning system suitable for scanning objects and architecture using a mobile stereoscopic camera combined with an inertial navigation sensor. The inertial navigation system acts as a coarse estimator for rapid registration and camera localization. Our scanning apparatus is assembled entirely using commercially available hardware, and the scanning process itself requires no technical skill and our system may be adapted to a wide variety of scanning conditions. We also introduce a set of heuristics for multi view data registration that aim to produce reliable and repeatable convergence despite the diversity of potential subjects, and different types of motions that may be executed by the operator during the scanning process. A surface reconstruction technique is used to generate a mesh, and subsequent texturing of the model is done through interpolation of the per vertex colour information extracted from the rectified colour images recorded by the camera. By texturing the surface of an object in a 3D application, the realism of the product is greatly increased. The results presented will show that our system is a viable solution for reproducing fully textured polygonal models with low surface deviation and realistic visual appearance.
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Shen, Wei. "Image based body dimension measurement /." View abstract or full-text, 2010. http://library.ust.hk/cgi/db/thesis.pl?MECH%202010%20SHEN.
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Slater, Thomas Jack Alfred. "Three dimensional chemical analysis of nanoparticles using energy dispersive X-ray spectroscopy." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/three-dimensional-chemical-analysis-of-nanoparticles-using-energy-dispersive-xray-spectroscopy(3eb607a2-eb03-4d45-b9eb-71b0ca45c2db).html.
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The aim of this thesis is to investigate the methodology of three dimensional chemical imaging of nanoparticles through the use of scanning transmission electron microscope (STEM) – energy dispersive X-ray (EDX) spectroscopy. In this thesis, an absorption correction factor is derived for spherical nanoparticles that can correct X-ray absorption effects. Quantification of EDX spectra of nanoparticles usually neglects X-ray absorption within the nanoparticle but may lead to erroneous results, thus an absorption correction is important for accurate compositional quantification. The absorption correction presented is verified through comparison with experimental data of Au X-ray peaks in spherical Au nanoparticles and is found to agree excellently. This absorption correction allows accurate compositional quantification of large ( > 100 nm) particles with STEM-EDX.Three dimensional chemical mapping is achievable through the use of EDX spectroscopy with electron tomography. Here, the methodology of STEM-EDX tomography is fully explored, with a focus on how to avoid artefacts introduced through detector shadowing and low counts per pixel. A varied-time acquisition scheme is proposed to correct for detector shadowing that is shown to provide a more constant intensity over a series of projections, allowing a higher fidelity reconstruction. The STEM-EDX tomography methodology presented is applied to the study of AgAu nanoparticles synthesized by the galvanic replacement reaction. The elemental distribution as a function of the composition of the as-synthesized nanoparticles is characterised and a reversal in the element segregated to the surface of the nanoparticles is found. The composition at which the reversal takes place is shown to correlate with a peak in the catalytic yield of a three component coupling reaction. It is hypothesized that a continuous Au surface results in the optimum catalytic conditions for the reaction studied, which guides the use of galvanically prepared AgAu nanoparticles as catalysts.
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Zhao, Yihua. "FROM CARDIAC OPTICAL IMAGING DATA TO BODY SURFACE ECG: A THREE DIMENSIONAL VENTRICLE MODEL." UKnowledge, 2014. http://uknowledge.uky.edu/cbme_etds/21.
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Understanding the mechanisms behind unexplained abnormal heart rhythms is important for diagnosis and prevention of arrhythmias. Many studies have investigated the mechanisms at organ, tissue, cellular and molecular levels. There is considerable information available from tissue level experiments that investigate local action potential properties and from optical imaging to observe activity propagation properties at an organ level. By combining those electrophysiological properties together, in the present study we developed a simulation model that can help in estimation of the resulting body surface potentials from a specific electrical activity pattern within the myocardium. Some of the potential uses of our model include: 1) providing visualization of an entire electrophysiological event, i.e. surface potentials and associated source which would be optical imaging data, 2) estimation of QT intervals resulting from local action potential property changes, 3) aiding in improving defibrillation therapy by determining optimal timing and location of shocks.
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Kwong, C.-M. "Three-dimensional separated flow prediction on fusiform body using Euler and boundary layer methods." Thesis, University of Salford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234623.
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Funatomi, Takuya. "Three dimensional shape modeling of human body in various postures by light stripe triangulation." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/59294.
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Moura, Lincoln de Assis. "A system for the reconstruction, handling and display of three-dimensional medical structures." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47192.
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Manuel, Melissa Barnes Ulrich Pamela V. Connell Lenda Jo. "Using 3D body scan measurement data and body shape assessment to build anthropometric profiles of tween girls." Auburn, Ala, 2009. http://hdl.handle.net/10415/1585.
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Tam, Chung-yan Candy. "Study of rock joint roughness using 3D laser scanning technique." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/b40203487.
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Tam, Chung-yan Candy, and 譚頌欣. "Study of rock joint roughness using 3D laser scanning technique." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40203487.
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Lewark, Erick A. "Automated techniques in anthropometry using a three dimensional laser scanner." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176485676.
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Mahajan, Aarti Y. Ulrich Pamela V. Connell Lenda Jo. "Comparing self and others' perceptions of adolescent girls' body size using figural stimuli and 3d body scans." Auburn, Ala, 2009. http://hdl.handle.net/10415/1586.
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Mandal, Rahul. "Calibration and adjustment of coherence scanning interferometry." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/17357.
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Coherence scanning interferometry (CSI) is a non-contacting optical technique which is widely used for the measurement of surface topography. CSI combines the lateral resolution of a high power microscope with the axial resolution of an interferometer. As with any other metrology instrument, CSI is calibrated to define measurement uncertainty. The traditional calibration procedure, as recommended by instrument manufacturers, consists of calibration of the axial and lateral scales of the instrument. Although calibration in this way provides uncertainties for the measurement of rectilinear artefacts, it does not give information about tilt-related uncertainty. If an object with varying slope is measured, significant errors are observed as the surface gradient increases. In this thesis a novel approach of calibration and adjustment for CSI using a spherical object is introduced. This new technique is based on three dimensional linear filtering theory. According to linear theory, smooth surface measurement in CSI can be represented as a linear filtering operation, where the filter is characterised either by point spread function (PSF) in space domain or by transfer function (TF) in spatial frequency domain. The derivation of these characteristics usually involves making the Born approximation, which is strictly only applicable for weakly scattering objects. However, for the case of surface scattering and making use of the Kirchhoff approximation, the system can be considered linear if multiple scattering is assumed to be negligible. In this case, the object is replaced by an infinitely thin foil-like object, which follows the surface topography and, therefore, is called the foil model of the surface. For an ideal aberration free instrument, the linear characteristics are determined by the numerical aperture of the objective lens and the bandwidth of the source. However, it is found that the PSF and TF of a commercial instrument can depart significantly from theory and result in a significant measurement error. A new method, based on modified inverse filter to compensate the phase and amplitude-related errors in the system PSF/TF, is demonstrated. Finally, a method based on de-warping to compensate distortion is discussed. The application of the linear theory as well as modified inverse filter is dependent on the assumption of the shift invariance. As distortion introduces a field dependent magnification, the presence of distortion for CSI with relatively large field of view, restricts the applicability of the linear theory. Along with this restriction, distortion also introduces erroneous height measurement for objects with gradients. This new approach, based on de-warping, resolves the problems associated with distortion.