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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Three dimensional stereo display systems.

January 1992 (has links)
by Li Lung Ming. / Thesis (M.Sc.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 33-34). / Chapter 0. --- Abstract --- p.3 / Chapter 1. --- Introduction --- p.4 / Chapter 1.1 --- Stereoscopic Applications --- p.4 / Chapter 1.2 --- How to perceive 3-D image --- p.6 / Chapter 1.2.1 --- Monocular Cues --- p.6 / Chapter 1.2.2 --- Binocular cues --- p.7 / Chapter 2 --- Background --- p.9 / Chapter 2.1 --- True 3 -D Display --- p.9 / Chapter 2.1.1 --- Stereoscopic Systems --- p.9 / Chapter 2.1.2 --- Head-Mounted Display --- p.11 / Chapter 2.1.3 --- Varifocal-mirror Display --- p.12 / Chapter 2.1.4 --- Holographic Systems --- p.13 / Chapter 2.2 --- Generation of real-time Stereoscopic Views --- p.15 / Chapter 3. --- A Stereoscopic System --- p.21 / Chapter 3.1 --- Design Considerations --- p.21 / Chapter 3.2 --- The Set-up --- p.22 / Chapter 4. --- Results --- p.26 / Chapter 5. --- Discussions --- p.27 / Chapter 5.1 --- Advantages of the set-up --- p.29 / Chapter 5.2 --- Disadvantages of the set-up --- p.30 / Chapter 6. --- Conclusion --- p.31 / Chapter 7. --- References --- p.33
162

Diseño e implementación de un sistema automático de medición de volumen de cajas de 5cm a 20cm de lado basado en sensores de proximidad

Llallico Tovar, Vladimir Edmundo, Jiménez Carpio, Juan Diego, Herrera Jiménez, José Alejandro 08 August 2015 (has links)
Actualmente, debido al crecimiento exorbitante de comercio de productos de consumo masivo, las industrias tienen la necesidad de contar con una mejor organización, gestión y control de los procesos en el ámbito logístico, para poder asegurar el uso de manera eficiente, eficaz y efectiva de los recursos materiales, financieros y humanos con los que cuenta. Un aspecto importante en el área logística de las empresas es el almacenamiento de las existencias, donde se requiere controlar y sistematizar de manera adecuada y segura la utilización de las instalaciones, pues representan buena parte de los gastos que tienen que realizar las empresas. Asimismo, el transporte de los productos es otro factor que interviene y determina el desarrollo y evolución de la logística, pues las industrias necesitan conocer e identificar los volúmenes exactos de productos que requerirá de sus proveedores o entregará a sus clientes para poder calcular los costos y usar de manera eficiente los recursos de este rubro. Por otra parte, las empresas requieren de un sistema de control de calidad de sus productos, para la detección y control de errores que se pueden presentar en ellos. El presente trabajo propone una solución alternativa a la deficiente supervisión de los procesos involucrados en las industrias de fabricación de productos de consumo masivo, para ello se diseñará e implementará un sistema de dimensionamiento automático de cajas, que sirven para el empaque de los productos, con el objetivo de identificar y calcular los volúmenes de espacio requeridos por la empresa, costos de los procesos de almacenamiento y transporte, e implementar un sistema de control de calidad de las existencias para poder asegurar la entrega de un producto bueno y terminado a los clientes. / Tesis
163

Yield and reliability enhancement for 3D-stacked ICs. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Jiang, Li. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 149-155). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
164

Biomechanical investigations of bend running technique in athletic sprint events

Churchill, Sarah January 2012 (has links)
For sprint events longer than 100 m, more than half the race is run on the bend, yet bend sprinting has received little attention in biomechanics literature. The aim of this thesis was to understand the effect of the bend on maximal effort sprint performance and technique, using bend radii and surfaces typical of outdoor competition. Three empirical studies were undertaken with experienced bend sprinters. Initial 3D kinematics investigations revealed an approximately 5% velocity decrease on the bend compared to the straight. However, step characteristic changes contributing to this reduction were different for the left and right steps. For the left step there were significant decreases in step frequency (p < 0.05), due to increased ground contact time, which agreed with previously proposed theoretical models. For the right step, however, a significantly reduced flight time resulted in a significant reduction in step length (p < 0.05). Maintaining step length and an ‘active touchdown’ were closely related to an athlete’s ability to better maintain straight line velocity on the bend. Generally, velocity decreased as bend radius decreased, with mean differences of up to 2.3% between lanes 8 and 2. However, changes to athletes’ technique due to different lanes were not conclusive. Ground reaction forces revealed between-limb differences during bend sprinting. Furthermore, frontal plane forces were up to 2.6 times larger on the bend than on the straight. Overall, asymmetries were identified between left and right steps for several performance, technique and force variables, suggesting that bend sprinting induces different functional roles between left and right legs, with the left step contributing more to turning to remain on the bend trajectory. The differences in kinematic and kinetic characteristics between the bend and straight, and between-limb asymmetries mean that athletes should apply the principle of specificity to bend sprinting training and conditioning, without sacrificing straight line technique.
165

Harmonious Storm

DOU, JIAYUN January 2011 (has links)
The intention with this imaginary storm in the form of a decorative lamp ‘Harmonious Storm’ is meant to hang from the ceiling, sculptural and often glowing with artificial light. Meanwhile it enhances the attractive value in the specific public space. The relation between importance of aesthetics and interior public environment is discussed in this thesis, with a purpose of achieving emotional and social needs that are excitement and happiness. / Program: Konstnärligt masterprogram i mode- och textildesign
166

Growth rate of 3-manifold homologies under branched covers

Cornish, James Stevens January 2018 (has links)
Over the last twenty years, a main focus of low-dimensional topology has been on categorified knot invariants such as knot homologies. This dissertation studies the case of two such homologies under the iteration of branched covering maps. In the first part, we find a spectral sequence on the sutured annular Khovanov homology of periodic links of period $r=2^i$. In the second part, we study the asymptotic growth rate of Heegaard Floer homology of cyclic branched covers of a knot as the branching number increases.
167

Three-dimensional reconstruction outside of the laboratory

Bennett, Stuart Charles January 2014 (has links)
No description available.
168

Simultaneous modelling and clustering of visual field data

Jilani, Mohd Zairul Mazwan Bin January 2017 (has links)
In the health-informatics and bio-medical domains, clinicians produce an enormous amount of data which can be complex and high in dimensionality. This scenario includes visual field data, which are used for managing the second leading cause of blindness in the world: glaucoma. Visual field data are the most common type of data collected to diagnose glaucoma in patients, and usually the data consist of 54 or 76 variables (which are referred to as visual field locations). Due to the large number of variables, the six nerve fiber bundles (6NFB), which is a collection of visual field locations in groups, are the standard clusters used in visual field data to represent the physiological traits of the retina. However, with regard to classification accuracy of the data, this research proposes a technique to find other significant spatial clusters of visual field with higher classification accuracy than the 6NFB. This thesis presents a novel clustering technique, namely, Simultaneous Modelling and Clustering (SMC). SMC performs clustering on data based on classification accuracy using heuristic search techniques. The method searches a collection of significant clusters of visual field locations that indicate visual field loss progression. The aim of this research is two-fold. Firstly, SMC algorithms are developed and tested on data to investigate the effectiveness and efficiency of the method using optimisation and classification methods. Secondly, a significant clustering arrangement of visual field, which highly interrelated visual field locations to represent progression of visual field loss with high classification accuracy, is searched to complement the 6NFB in diagnosis of glaucoma. A new clustering arrangement of visual field locations can be used by medical practitioners together with the 6NFB to complement each other in diagnosis of glaucoma in patients. This research conducts extensive experiment work on both visual field and simulated data to evaluate the proposed method. The results obtained suggest the proposed method appears to be an effective and efficient method in clustering visual field data and 3 improving classification accuracy. The key contributions of this work are the novel model-based clustering of visual field data, effective and efficient algorithms for SMC, practical knowledge of visual field data in the diagnosis of glaucoma and the presentation a generic framework for modelling and clustering which is highly applicable to many other dataset/model combinations.
169

Intuitive freeform modeling using subdivision surfaces.

January 2005 (has links)
Lai Yuen-hoo. / Thesis submitted in: November 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 100-102). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.ii / Acknowledgment --- p.iii / List of Figures --- p.iv / Table of Content --- p.vii / Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- Problem Definition --- p.1 / Chapter 1.2. --- Proposed Solution --- p.2 / Chapter 1.3. --- Thesis Contributions --- p.2 / Chapter 2. --- Modeling Approaches --- p.4 / Chapter 2.1. --- Polygon Modeling --- p.4 / Chapter 2.2. --- Patch Modeling --- p.6 / Chapter 2.3. --- Freehand Sketch-based Modeling --- p.7 / Chapter 2.4. --- Template Based Modeling --- p.8 / Chapter 2.5. --- Curve Interpolation Method --- p.9 / Chapter 3. --- Surface Operations --- p.11 / Chapter 3.1. --- Surface Blending --- p.11 / Chapter 3.2. --- Surface Trimming --- p.13 / Chapter 3.3. --- Boolean Operations --- p.14 / Chapter 4. --- Subdivision Surface --- p.16 / Chapter 4.1. --- Basic Principle --- p.16 / Chapter 4.2. --- Catmull-Clark Surface --- p.17 / Chapter 5. --- Modeling Algorithm Overview --- p.21 / Chapter 6. --- Subdivision Surface Generation --- p.23 / Chapter 6.1. --- Input Curves --- p.23 / Chapter 6.2. --- Surface Sweeping --- p.24 / Chapter 6.3. --- Subdivision Surface Fitting --- p.29 / Chapter 7. --- Surface Blending --- p.32 / Chapter 7.1. --- Introduction --- p.32 / Chapter 7.2. --- Problem Definition --- p.32 / Chapter 7.3. --- Algorithm Overview --- p.36 / Chapter 7.4. --- Blend Region Detection --- p.39 / Chapter 7.4.1. --- Collision Detection --- p.40 / Chapter 7.4.2. --- Result and Analysis --- p.42 / Chapter 7.5. --- "Mesh Refinement, Surface Fitting and Region Removal" --- p.46 / Chapter 7.5.1. --- Mesh Refinement --- p.46 / Chapter 7.5.1.1. --- Adaptive Subdivision --- p.46 / Chapter 7.5.1.2. --- Additional Subdivision Constraint --- p.47 / Chapter 7.5.2. --- Surface Fitting --- p.49 / Chapter 7.5.2.1. --- General Approach --- p.49 / Chapter 7.5.2.2. --- Surface Point Correspondence --- p.50 / Chapter 7.5.2.3. --- Numerical Fitting Method --- p.51 / Chapter 7.5.3. --- Unwanted Region Removal --- p.55 / Chapter 7.5.4. --- Result and Analysis --- p.56 / Chapter 7.6. --- Boundary Smoothing --- p.58 / Chapter 7.6.1. --- General Approach --- p.59 / Chapter 7.6.2. --- Constraint on Deformation Direction of Vertex --- p.61 / Chapter 7.6.3. --- Result and Analysis --- p.63 / Chapter 7.7. --- Blend Curves --- p.65 / Chapter 7.7.1. --- Problem Definition --- p.65 / Chapter 7.7.2. --- Proposed Solution Overview --- p.66 / Chapter 7.7.3. --- Maintenance of Regular Vertex Valence along Blend Curve --- p.67 / Chapter 7.7.3.1. --- Pairing Up Blend Boundary Vertices --- p.70 / Chapter 7.7.4. --- Minimization of Distortion Caused by Extraordinary Vertices --- p.72 / Chapter 7.7.5. --- Blend Vertex Position Optimization Function --- p.74 / Chapter 7.7.5.1. --- Face Normal Expression --- p.74 / Chapter 7.7.5.2. --- Face Normal Difference Energy Function --- p.77 / Chapter 7.7.5.3. --- Midpoint Distance Energy Function --- p.78 / Chapter 7.7.5.4. --- Weighted Least Square Energy Minimization --- p.78 / Chapter 8. --- Implementation --- p.81 / Chapter 8.1. --- Data Structure --- p.81 / Chapter 8.2. --- User Interface --- p.82 / Chapter 9. --- Results --- p.83 / Chapter 9.1. --- Surface Generation --- p.83 / Chapter 9.2. --- Surface Blending --- p.86 / Chapter 9.2.1. --- Ideal Case --- p.86 / Chapter 9.2.2. --- Angle of Insertion --- p.87 / Chapter 9.2.3. --- Surface Feature Near Intersection --- p.88 / Chapter 9.2.4. --- Comparison --- p.89 / Chapter 9.2.5. --- Other Examples --- p.92 / Chapter 9.3. --- Overall Performance --- p.94 / Chapter 9.4. --- Limitations --- p.97 / Chapter 9.4.1. --- Limitation on Generated Shape --- p.97 / Chapter 9.4.2. --- Limitation on Input Surfaces --- p.98 / Chapter 10. --- Conclusion and Future Work --- p.99 / References --- p.100
170

Study of interface plasmon in low-dimensional silicon nanostructures. / 低維硅納米結構表界面等離激元之研究 / CUHK electronic theses & dissertations collection / Study of interface plasmon in low-dimensional silicon nanostructures. / Di wei gui na mi jie gou biao jie mian deng li ji yuan zhi yan jiu

January 2010 (has links)
In this thesis study, the surface/interface plasmon excitations in different Si nanostructures were revealed through the EELS study in TEM/STEM. In the case of the planar boundary such as the wedge-like specimen, the spatially resolved EELS results disclose the dependence of the intensity and the position of the interface plasmon peak on the sample thickness. In the case of the Si-core/ SiO2-shell nanoparticles, we found that the SP/IP peak will firstly red-shifts with the increase of the SiO2 shell thickness and eventually levels off . As the aspect ratio of the Si nanoparticles increases, (from spherical particle to nanorod and nanowire), the SP/IP will split into two branches: transverse and longitudinal modes. We also found the intensity ratio of the transverse/longitudinal mode excitations depends on the diameter of the Si core size in the nanostructures. In the one-dimensional interacting Si nanoparticle chains, the Si nanoparticles were embedded in the SiO 2 shell, the splitting of the SP excitation into transverse and longitudinal modes was also observed. As the inter-particle distance reduces to several nanometers, the coupling of the IP excitation between the adjacent particles becomes significant, and results in the local field enhancement in-between the two particles. This is directly visualized using EFTEM imaging in TEM/STEM. / Surface/interface plasmons (SP/IP) are the plasmons confined at specific boundaries, describing the surface/interface charge density oscillation. They are generated when the scattered electromagnetic wave with its scattering vector component parallel to the boundary propagates along the surface/interface. Study of surface plasmon resonance in noble metals such as gold and silver nanoparticles have started decades ago, and recent interests are focused on the plasmonic properties of individual nanoparticles, as enabled by the size/shape control in the nanostructure growth and advances made in the characterization methodologies. Besides the noble metals, semiconductor such as silicon also attracts much attention for its plasmonic behavior. The surface/interface plasmon resonance frequency of Si-based nanostructures occurs at relatively higher energies (compared to Au and Ag), making it a perfect system to be studied using electron energy loss spectroscopy (EELS) based techniques. When performed in a scanning transmission electron microscope (STEM), such a technique enjoys excellent spatial resolution, and can map the local plasmonic properties of individual nanostructures. / The plasmon excitation depends sensitively on not only the material dielectric properties but also the geometrical configurations of the material. In the present thesis work, silicon-based nanostructures with planar, spherical, and cylindrical boundaries were investigated using both experimental and theoretical approaches, with focus on the plasmon oscillation originating from the Si/SiO 2 interface. The specimens employed include silicon/silica thin films, Si-core/SiO2-shell nanoparticles with different aspect ratios and spherical-shaped nanoparticle chains, as well as Si-core/SiO2-shell nanocables. / Wang, Xiaojing = 低維硅納米結構表界面等離激元之研究 / 王笑靜. / Adviser: Li Quan. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 118-122). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Wang, Xiaojing = Di wei gui na mi jie gou biao jie mian deng li ji yuan zhi yan jiu / Wang Xiaojing.

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