Chow, Yuk Pui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 83-87). / Abstracts in English and Chinese. / Chapter 1. --- Introduction --- p.13-16 / Chapter 1.1. --- Motivation --- p.13 / Chapter 1.2 --- Objectives --- p.14-15 / Chapter 1.3 --- Thesis Organization --- p.16 / Chapter 2. --- Related Works --- p.17-24 / Chapter 2.1 --- Axial and the Free Form Deformation --- p.17 / Chapter 2.1.1 --- The Free-Form Deformation --- p.18 / Chapter 2.1.2 --- The Lattice-based Representation --- p.18 / Chapter 2.1.3 --- The Axial Deformation --- p.19-20 / Chapter 2.1.4 --- Curve Pair-based Representation --- p.21-22 / Chapter 2.2 --- Self Intersection Detection --- p.23-24 / Chapter 3. --- Axial Deformation with Controllable LCFs --- p.25-46 / Chapter 3.1 --- Related Methods --- p.25 / Chapter 3.2 --- Axial Space --- p.26-27 / Chapter 3.3 --- Definition of Local Coordinate Frame --- p.28-29 / Chapter 3.4 --- Constructing Axial Curve with LCFs --- p.30 / Chapter 3.5 --- Point Projection Method --- p.31-32 / Chapter 3.5.1 --- Optimum Reference Axial Curve Point --- p.33 / Chapter 3.6 --- Advantages using LCFs in Axial Deformation --- p.34 / Chapter 3.6.1 --- Deformation with Smooth Interpolated LCFs --- p.34-37 / Chapter 3.6.2 --- Used in Closed-curve Deformation --- p.38-39 / Chapter 3.6.3 --- Hierarchy of Axial Curve --- p.40 / Chapter 3.6.4 --- Applications in Soft Object Deformation --- p.41 / Chapter 3.7 --- Experiments and Results --- p.42-46 / Chapter 4. --- Self Intersection Detection of Axial Curve with LCFs --- p.47-76 / Chapter 4.1 --- Related Works --- p.48-49 / Chapter 4.2 --- Algorithms for Solving Self-intersection Problem with a set of LCFs --- p.50-51 / Chapter 4.2.1 --- The Intersection of Two Plane --- p.52 / Chapter 4.2.1.1 --- Constructing the Normal Plane --- p.53-54 / Chapter 4.2.1.2 --- A Line Formed by Two Planes Intersection --- p.55-57 / Chapter 4.2.1.3 --- Problems --- p.58 / Chapter 4.2.1.4 --- Sphere as Constraint --- p.59-60 / Chapter 4.2.1.5 --- Intersecting Line between Two Circular Discs --- p.61 / Chapter 4.2.2 --- Distance between a Mesh Vertex and a Curve Point --- p.62-63 / Chapter 4.2.2.1 --- Possible Cases of a Line and a Circle --- p.64-66 / Chapter 4.3 --- Definition Proof --- p.67 / Chapter 4.3.1 --- Define the Meaning of Self-intersection --- p.67 / Chapter 4.3.2 --- Cross Product of Two Vectors --- p.68 / Chapter 4.4 --- Factors Affecting the Accuracy of the Algorithm --- p.69 / Chapter 4.3.1 --- High Curvature of the Axial Curve --- p.69-70 / Chapter 4.3.2 --- Mesh Density of an Object. --- p.71-73 / Chapter 4.5 --- Architecture of the Self Intersection Algorithm --- p.74 / Chapter 4.6 --- Experimental Results --- p.75- 79 / Chapter 5. --- Conclusions and Future Development --- p.80-82 / Chapter 5.1 --- Contribution and Conclusions --- p.80-81 / Chapter 5.2 --- Limitations and Future Developments --- p.82 / References --- p.83-87

Tao, Chenjun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 89-97). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Window-oriented Retargeting --- p.1 / Chapter 1.2 --- Abstraction Rendering --- p.4 / Chapter 1.3 --- Thesis Outline --- p.6 / Chapter 2 --- Related Work --- p.7 / Chapter 2.1 --- Video Migration --- p.8 / Chapter 2.2 --- Video Synopsis --- p.9 / Chapter 2.3 --- Periodic Motion --- p.14 / Chapter 2.4 --- Video Tracking --- p.14 / Chapter 2.5 --- Video Stabilization --- p.15 / Chapter 2.6 --- Video Completion --- p.20 / Chapter 3 --- Active Window Oriented Video Retargeting --- p.21 / Chapter 3.1 --- System Model --- p.21 / Chapter 3.1.1 --- Foreground Extraction --- p.23 / Chapter 3.1.2 --- Optimizing Active Windows --- p.27 / Chapter 3.1.3 --- Initialization --- p.29 / Chapter 3.2 --- Experiments --- p.32 / Chapter 3.3 --- Summary --- p.37 / Chapter 4 --- Multi-Style Abstract Image Rendering --- p.39 / Chapter 4.1 --- Abstract Images --- p.39 / Chapter 4.2 --- Multi-Style Abstract Image Rendering --- p.42 / Chapter 4.2.1 --- Multi-style Processing --- p.45 / Chapter 4.2.2 --- Layer-based Rendering --- p.46 / Chapter 4.2.3 --- Abstraction --- p.47 / Chapter 4.3 --- Experimental Results --- p.49 / Chapter 4.4 --- Summary --- p.56 / Chapter 5 --- Interactive Abstract Videos --- p.58 / Chapter 5.1 --- Abstract Videos --- p.58 / Chapter 5.2 --- Multi-Style Abstract Video --- p.59 / Chapter 5.2.1 --- Abstract Images --- p.60 / Chapter 5.2.2 --- Video Morphing --- p.65 / Chapter 5.2.3 --- Interactive System --- p.69 / Chapter 5.3 --- Interactive Videos --- p.76 / Chapter 5.4 --- Summary --- p.77 / Chapter 6 --- Conclusions --- p.81 / Chapter A --- List of Publications --- p.83 / Chapter B --- Optical flow --- p.84 / Chapter C --- Belief Propagation --- p.86 / Bibliography --- p.89

隨著互聯網上3D模型的大量增加，產生了開發3D模型搜索引擎的需求。本論文提出了一個基於草圖和3D模型的3D模型搜索引擎。 / 對於使用3D模型作檢索條件的搜索系統，我們提出了兩種新的3D模型描述子，分別叫做Sphere Image 描述子和Bag-of-View-Words (BoVW)描述子。Sphere Image描述子是由一系列投影圖的特徵組成。我們將每一個視角看到的圖形都當作是一個"像素"，把視角的位置看作像素點的位置，把所看到的圖形的特徵值看作是像素值。我們同時也提出了一種基於概率圖的3D模型匹配算法，並開發了一個3D模型檢索系統來檢測我們的算法。BoVW描述子通過3D模型投影圖出現的次數來描述3D模型。我們用一種自適應的聚類算法，對3D模型的所有投影圖進行分類，然後用一個多層次的柱狀圖來描述一個3D模型。我們同時提出一種新的金字塔匹配算法來比較3D模型。我們使用SHREC和普林斯頓的3D模型庫來檢驗我們的系統，實驗結果證明我們的系統在檢索效率和精度上都優與現今的3D模型檢索系統。 / 對於使用草圖作檢索條件的3D模型搜索系統，我們提出Bigger ExposureOpportunity Views (BEOV) 描述子來表示3D模型，同時提出Shape-Ring描述子來表示草圖。BEOV描述子是由一些特徵圖組成，這些圖的特點是更容易被人們看到。Shape-Ring描述子保留了圖形的輪廓和內部特徵。我們使用SHREC2012草圖數據庫來檢驗我們的系統，實驗結果證明我們的系統在精度和計算複雜度上都優與現今的3D模型檢索系統。 / The large number of 3D models on the Internet encourages us to develop 3D model search engines. In this dissertation, we present a 3D model retrieval system using both the 3D model query and the sketch query. / For 3D model query based retrieval system, we propose two new 3D model descriptors, named the Sphere Image and the Bag-of-View-Words (BoVW) descriptor. The Sphere Image is defined as a collection of view features. A viewpoint of a 3D model is regarded as a "pixel": (1) The position of the viewpoint is denoted as the coordinate of the "pixel". (2) The feature descriptor of the projected view is denoted as the value of the "pixel". We also propose a probabilistic graphical model for 3D model matching, and develop a 3D model retrieval system to test our approach. The BoVW descriptor describes a 3D model by measuring the occurrences of its projected views. An adaptive clustering method is applied to reduce the redundancy of the projected views of each 3D model. A 3D model is represented by a multi-resolution histogram, which is combined by several BoVW descriptors at different levels. The codebook is obtained by unsupervised learning. We also propose a new pyramid matching method for 3D model comparison. We have conducted experiments based on the SHape REtrieval Contest (SHREC) 2012 Generic 3D model benchmark and the Princeton Shape Benchmark (PSB). Experimental results indicate that our system outperforms some state-of-the-art 3D model retrieval systems with respect to the retrieval precision and the computational cost. / For sketch query based retrieval system, we propose a Bigger Exposure Opportunity Views (BEOV) descriptor and a Shape-Ring descriptor, for representing the 3D model candidates and the sketch query, respectively. The BEOV descriptor represents a 3D model by several characteristic views, which have more chances to be exposed to people. The Shape-Ring descriptor preserves the features of the contour and the inside detail of the sketch query and the BEOV. Experiments have been conducted based on the SHape REtrieval Contest (SHREC) 2012 and SHREC 2013 sketch track data sets. Our approach outperforms the existing 3D model retrieval methods in terms of the retrieval precision and the computational cost. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Ding, Ke. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 107-120). / Abstracts also in Chinese.

BACKGROUND: Calcific aortic valve disease (CAVD) is the most prevalent heart valve disease in the developed world, claiming almost 17,000 deaths annually in the United States. The lack of noninvasive therapeutics to slow or halt the disease warrants the need for further understanding of the pathobiological mechanisms of CAVD. A tri-laminar structure of aortic valve determines the biomechanical properties of its leaflets. Valvular endothelial cells (VECs) and interstitial cells (VICs) are responsible for valve structural integrity. Traditional two-dimensional culture conditions spontaneously activate the pathological differentiation of VICs making in vitro studies challenging. A monolayered three-dimensional (3D) hydrogel platform was recently developed as a novel in vitro culture system to study the phenotypic changes of VICs leading to microcalcification (early stages of calcification). This system, however, did not fully recapitulate the microenvironment of native valve tissues because of the lack of individual layer representations and endothelial coverage. Bioprinting technology, which allows precise and integrated positioning of cells, matrix, and biomolecules, may provide an innovative approach toward building a more biologically relevant 3D culture platform. OBJECTIVE: This study aims to lay the groundwork for building a multilayered 3D-bioprinted culture platform to study CAVD by first validating the use of bioprinting in monolayered cell-laden 3D hydrogel constructs. METHODS: Human VICs were isolated from patients undergoing valve replacement surgeries at Brigham and Women’s Hospital (Boston, MA) according to Institutional Review Board (IRB) protocols. VICs were expanded in culture medium containing growth factors for up to 6 passages and then encapsulated in hydrogels using 3D bioprinting technology. After encapsulation, VIC-laden 3D constructs were cultured in either normal or osteogenic conditions for 21 days. Microcalcification, cell proliferation, and cell apoptosis were evaluated using fluorescent staining and confocal microscopy. Results were compared with results from VIC-laden hydrogels made manually. RESULTS: An increase in microcalcification was observed throughout bioprinted VIC-laden hydrogel constructs cultured in osteogenic conditions for 21 days, whereas normal conditions developed negligible calcification signals. Cell proliferation and apoptosis were not significantly different between normal and osteogenic groups in bioprinted hydrogels. Cell-free hydrogels did not exhibit any microcalcification. Overall, bioprinted hydrogels showed less nonspecific background staining than handmade hydrogels, thus providing a better means for quantitative assessments of 3D culture platforms. CONCLUSION: Based on bioprinting technology, an improved monolayered cell-laden hydrogel platform was successfully established as a first step toward building an in vitro multilayered disease model for studying the pathobiological mechanisms of CAVD. The results in this study were consistent with current literature that proposes calcification as a cell-dependent, apoptotic-independent, and proliferation-independent pathway. / 2019-07-13T00:00:00Z

Introdução: A avaliação endometrial à ultrassonografia, em geral, tem sua aplicação clínica em larga escala dentro do ciclo reprodutivo feminino, porém, (até onde se sabe), sem uma forma padronizada para a realização dessas medidas. Objetivo: O objetivo deste estudo foi avaliar se a padronização do exame ultrassonográfico tridimensional (US-3D) do útero ao modo multiplanar -\"standardization of the multiplanar view\" - (SMV) melhora a confiabilidade intra e interobservador e a concordância em relação às medidas endometriais. Casuística e Métodos: Foram realizados exames utrassonográficos, ao modo bidimensional (US-2D) e tridimensional (US-3D) em 30 mulheres submetidas a tratamento em reprodução assistida. Dois observadores mediram a espessura endometrial utilizando US-2D e US-3D. O volume endometrial foi avaliado por meio do sistema computadorizado VOCAL(TM) em planos longitudinal (A) e coronal (C) utilizando o exame multiplanar de forma não padronizada - \"unmodified multiplanar view\" (UMV) e aquele sob a forma padronizada - \"standardized multiplanar view\" (SMV). O coeficiente de correlação intraclasse (CCI) foi empregado para avaliar a confiabilidade entre as medidas. A concordância foi avaliada colculando-se a média das diferenças e dos \"limites de concordância de Bland-Altman (LoA)\". O grau de facilidade em delimitar e contornar a interface endométrio-miométrio ao plano A ou C foi determinado de forma subjetiva. Resultados: A medida do volume endometrial utilizando o SMV ao plano A mostrou-se mais confiável (IC intra e interobservador 0,979 e 0,975) do que a medida da espessura endometrial utlizando US-2D (CCI = 0,742 e 0,702) ou US-3D (CCI = 0,890 e 0,784). Os limites de concordância interobservadores e confiabilidade intraobservador para medidas do volume endometrial foram maiores ao método padronizado (SMV) utilizando o plano A, do que aquele não padronizado (VUM), tanto ao plano A quanto ao plano C. Chama a atenção os intervalos de confiança serem ainda mais estreitos ao plano A. Não houve diferença significativa com relação à confiabilidade ou concordância entre as medidas realizadas, tanto ao plano A quanto ao plano C, utilizando-se o método padronizado (SMV). No entanto, os observadores concordaram que o delineamento da interface endométrio-miométrio a partir do plano A foi mais fácil (50,0% para o primeiro observador e 46,7% para o segundo observador), ou comparáveis aos planos A e C (50% para o primeiro observador e 53,3% para o segundo observador), mas nunca ao plano A mais difícil do que ao plano C. Conclusões: As medidas do volume endometrial são mais confiáveis do que as da espessura endometrial, sendo melhor realizadas quando utilizado o método padronizado (SMV) ao plano A. / Introduction: Endometrial assessment with ultrasonography usually has its clinical application on a large scale in female reprodutive cycle but (as far as we know) without a standard way to perform these measures. Objective: The objective of this study was to evaluate if standardization of the multiplanar view (SMV) when assessing the uterus using three-dimensional ultrasonography (3D-US) improves the intra- and interobserver reliability and agreement with regard to endometrial measurements. Casuistic and Methods: Ultrasound imaging exams were performed, using the bidimensional ultrasonography (2D US) and 3D-US, in 30 women undergoing assisted reproduction treatment. Endometrial thickness was measured by two observers using 2D-US and 3DUS. Endometrial volume was measured with VOCAL(TM) in the longitudinal (A) and Coronal (C) planes using an unmodified multiplanar view (UMV) and a standardized multiplanar view (SMV). Measurement reliability was evaluated by intraclass correlation coefficient (ICC) and agreement was evaluated by calculating mean difference and limits of agreement (LoA). The ease to contour the endometrial-myometrial interface was compared between the A and C plane using subjective assessment. Results: Endometrial volume measurements using the SMV and A plane were more reliable (Intra- and interobserver IC 0.979 and 0.975) than measurements of endometrial thickness using 2D-US (ICC=0.742 and 0.702) or 3D-US (ICC=0.890 and 0.784). The interobserver agreement and intraobserver reliability for endometrial volume measurements was better using SMV and A plane than UMV using A or C plane LoA being narrower for the former. No significant difference in reliability or agreement was demonstrated between the A and C plane when using SMV. However the observers agreed that delineating the endometrial-myometrial interface using the A plane was easier (50.0% and 46.7%, first and second observer) o \'comparable\' (50% and 53.3%), but never more difficult than using the C plane. Conclusion: Endometrial volume measurements are more reliable than endometrial thickness measurements and are best performed using SMV and A plane.

This thesis works through the design of a radar-based system for imaging snowpacks remotely and over large areas to assist in avalanche prediction. The key to such a system is the ability to image volumes of snow at shallow, spatially-varying angles of incidence. To achieve this prerequisite, the design calls for a ground-based Synthetic Aperture Radar (SAR) capable of generating three-dimensional, ultra-high-resolution images of a snowpack. To arrive at design parameters for this SAR, the thesis works through relevant principles in avalanche mechanics, alpine-snowpack geophysics, and electromagnetic scattering theory. The thesis also works through principles of radar, SAR, antenna, and image processing theory to this end. A preliminary system is implemented to test the feasibility of the overall design. The preliminary system demonstrates ultra-high-resolution, three-dimensional imaging capabilities and the ability to image the volume of multiple alpine snowpacks. Images of these snowpacks display the structural patterns indicative of different layers in the snowpacks. Possible attributions of the patterns to physical properties in the snowpack are explored, but conclusions are not arrived at. Finally, lessons from the implementation of this preliminary system are discussed in terms of opportunities to be capitalized upon and problems to be overcome in future systems that more faithfully realize the complete design set forth in the thesis.

Healthcare costs for treating back pain have risen to 50 billion dollars a year in the past decade. In attempt reduce the risk of back pain; ergonomists use digital human modeling to assess the risks involved in functional tasks. However, current models are limited to analyzing the strength in static position. The overall goal of this study is to provide three-dimensional strength surfaces incorporating both static and dynamic strength for digital human models. Fifteen male and twenty-one female subjects were recruited. The study required two visits, were hip strength testing was performed in one visit and trunk strength testing was performed in the other visit. Hip strength was tested by completing flexion and extension isometric tests and isokinetic tests. Trunk flexion and extension strength was also measured by isometric and isokinetic tests. Isometric and Isokinetic tests were completed for trunk left and right rotation too. The data was analyzed using custom made MATLAB (Mathworks, Inc) programs and the three-dimensional strength surfaces were generated using SigmaPlot (SYSTAT Software, INC). The maximum peak torques were as followed: Hip flexion male 183Nm(57), hip flexion female 106 Nm (38), hip extension male 181 Nm (71), hip extension female 130 Nm (52), trunk flexion male 182 Nm (40.3), trunk flexion female 111.8 Nm (32), trunk extension male 328.5 Nm (52), trunk extension female 197.5 Nm (58), trunk right rotation male 71.6 Nm (20), trunk right rotation female 43 Nm (14), trunk left rotation male 71 Nm (24), and trunk left rotation female (43 Nm (17). Correlations were found between the hip and trunk joints, and the flexion and extension motion. Implementing this data into digital human models will provide realistic static and dynamic human strength parameters. Ultimately, this will help ergonomists predict and reduce high risk back injuries.

The purpose of this work is to study phenotypic craniofacial traits of unaffected parents of individuals with nonsyndromic cleft lip with or without palate (NSCL/P). In order to evaluate these craniofacial traits, three dimensional photographs were obtained and landmarked to compare the sample of unaffected parents with a control sample. The sample was comprised of 40 unaffected fathers, 25 control males, 84 unaffected mothers, and 34 control females. Twenty-four three-dimensional landmarks were exported for analysis for each subject. For the purposes of this study, nine euclidean distances were subjected to a discriminant function analysis to evaluate their ability to discriminate between an unaffected parent and a control. In both the male and female analysis, certain craniofacial measurements correctly and significantly discriminated between unaffected parents and controls. It appears that certain facial traits are subclinical markers for enhanced genetic susceptibility to nonsyndromic cleft lip with or without palate.

Two-dimensional (2-D) micro-autoradiography is typically used to identify the location of a radio-labeled ligand bound to a cellular target in tissue sections. Data, such as a histological image, combined with the autoradiographic data provide a spatial relationship of the radiolabel to cellular structures. However, the disadvantage of 2-D imaging is that it only provides a local distribution of the radiolabel within a tissue slice, and not a volumetric regional distribution in the structure of interest. The development of 3-D autoradiographic/histological visualizations would provide important information not otherwise apparent, such as the ability to visualize the distribution of the labeled agents in subcutaneous tissue. We plan to obtain digital micro-autoradiographic images and fuse them to their corresponding histological images using commercially available software. We plan to create a series of 2-D fused images. This series of 2-D fused images will then form a basis for creating 3-D visualization of autoradiographic/histological images using another commercially available software. These type of fused 3-D images, which we will refer to as micro-autoradiographic fusion tomography (MAFT), are not currently available. We will illustrate the use of MAFT with the distribution of vascular endothelial growth factor (VEGF) in subcutaneous tissue. [14C]-VEGF will be injected into rat subcutaneous tissue. VEGF has been found to stimulate angiogenesis, or the growth of new blood vessels, which could prove beneficial by aiding the function of an implantable blood glucose sensor. The diffusion coefficient for VEGF in subcutaneous tissue has not yet been characterized. MAFT would be an ideal technique to use for this type of study. My thesis will address the following specific aims: 1) To label the nicotine receptors in adult and adolescent rat brains, and to obtain digital micro-autoradiographic images and histological images; 2) To fuse a 2-D digital micro-autoradiographic image with a 2-D histological image; 3) To create a 3-D image from a series of 2-D fusion images; and 4) To assess the increased information value obtained using MAFT.

This study is the first in a series of planned studies on the application of multidimensional visualization of business information and data within the context of accounting. The study's research question is: When is multidimensional visualization of information a better problem representation, improving both the effectiveness and efficiency of a spatial accounting judgment? To examine when multidimensional visualization can assist auditors in configural cue pattern recognition, the study employs the traditional DuPont analysis as the three pieces of key information to be represented on the X, Y, and Z axes of a single 3-D perspective display. To help determine when use of 3-D perspective display is beneficial in combining pieces of information, I rely on Vessey's (1991) Cognitive Fit Theory, and the Proximity Compatibility Principle (PCP) proposed by Wickens and Carswell (1995). The study has two hypotheses. Hypothesis H1 predicted that participants viewing a set of 2-D displays will be the most effective or most efficient in generating hypotheses for what caused the changes in the trend of accounting data or in estimating values. Hypothesis H2 predicted that participants viewing a single 3-D perspective display will be the most effective or most efficient in recognizing patterns of accounting data or in generating hypotheses for what caused the emerged pattern. To test the hypotheses of the study a 3 x 2 between-subjects design (display format x task) is used. The independent variables are display types and task types. Graphical display was manipulated at three levels: no graphical display (table only), 2-D display, and 3-D perspective display. Task was manipulated at two levels: trend analysis and pattern recognition task. The need for a fit between different types of spatial tasks and display formats is demonstrated by the findings of this study: 1) that 2-D displays appear to be more suitable for spatial tasks involving the generation of hypotheses for causes of trends in accounting data, while 2) 3-D perspective displays appear to be more suitable for spatial tasks involving pattern recognition in accounting data.