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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.
61

Theoretical and numerical treatment of singularities in elliptic boundary value problems

Beagles, A. E. January 1987 (has links)
No description available.
62

Polymerization of 2D gravity models

Howard, Bruce January 1998 (has links)
No description available.
63

The fabrication and assessment of three-dimensional photonic crystals

Sharp, David Neil January 2001 (has links)
No description available.
64

Chemie mezivrstvového prostoru dvojrozměrných zeolitů / Chemistry of the Interlamellar Space of Two-dimensional Zeolites

Mazur, Michal January 2016 (has links)
The presented PhD thesis is focused on the synthesis, characterization, and modifications of zeolites and zeolitic materials. The main interests are two-dimensional (2D) zeolites and modification of their interlamellar space. Presented work was performed at the Department of Synthesis and Catalysis at J. Heyrovský Institute of Physical Chemistry in Prague, Czech Republic under the supervision of Prof. Jiří Čejka. Zeolites are inorganic crystalline solids with a microporous framework structure. They are widely used as catalysts, sorbents, and ion-exchangers. Conventional zeolites have been recognized as three-dimensional (3D) tetrahedrally-connected frameworks. However, some of them are also known to exist in various layered forms (2D zeolites). Recently, the transformation of 3D germanosilicate UTL into layers (IPC-1P) has started a new branch in 2D zeolites chemistry. This chemically selective degradation of UTL framework was performed via acid hydrolysis. In the structure of this germanosilicate, Ge atoms are preferentially located in specific building units, double-four-rings (D4R), which connect dense silica layers. Modifications of the layered precursor IPC-1P led to discovery of the two novel 3D zeolites: IPC-4 (PCR) and IPC-2 (OKO). This novel approach in the zeolite synthesis, called ADOR...
65

3D reconstruction of building site. / 建築物埸景的三維重建 / 3D reconstruction of building site. / Jian zhu wu yi jing de san wei zhong jian

January 2004 (has links)
Tsui Ping Tim = 建築物埸景的三維重建 / 徐秉添. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 82-85). / Text in English; abstracts in English and Chinese. / Tsui Ping Tim = Jian zhu wu yi jing de san wei zhong jian / Xu Bingtian. / Acknowledgement --- p.ii / Abstract --- p.iii / Table of Content --- p.v / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- A Brief Review on 3D Site Reconstruction --- p.1 / Chapter 1.2. --- Approach of the Project --- p.3 / Chapter 1.3. --- Organization of the Thesis --- p.4 / Chapter 1.3.1 --- The 3D Site Reconstruction --- p.4 / Chapter 1.3.2 --- The Conformal Point Theory --- p.5 / Chapter 1.4. --- Notations --- p.6 / Chapter Chapter 2. --- General System Overview --- p.7 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Ground Reconstruction --- p.8 / Chapter 2.2.1 --- Planar Homography --- p.9 / Chapter 2.2.2 --- Determination of the Planar Homography --- p.10 / Chapter 2.3 --- Buildings and Cliff Reconstruction --- p.13 / Chapter 2.3.1 --- Correspondence Extraction --- p.14 / Chapter 2.3.2 --- Self-Calibration --- p.17 / Chapter 2.3.3 --- Extrinsic Parameters Estimation --- p.17 / Chapter 2.3.4 --- Scene Point Coordinates Computation --- p.18 / Chapter 2.3.5 --- Bundle Adjustment --- p.19 / Chapter 2.4 --- Object Assimilation --- p.19 / Chapter 2.5 --- Summary --- p.21 / Chapter Chapter 3. --- Camera Calibration --- p.22 / Chapter 3.1 --- Introduction --- p.22 / Chapter 3.2 --- Chapter Organization --- p.22 / Chapter 3.3 --- Brief Review of Camera Calibration --- p.23 / Chapter 3.4 --- Camera Intrinsic Parameters --- p.23 / Chapter 3.5 --- Difficulty of the Calibration Problem --- p.25 / Chapter 3.6 --- Non-automatic Calibration --- p.26 / Chapter 3.6.1 --- DLT --- p.26 / Chapter 3.6.2 --- Vanishing Points Approach --- p.26 / Chapter 3.6.3 --- Homography Approach --- p.28 / Chapter 3.7 --- Auto-Calibration --- p.29 / Chapter 3.7.1 --- Square Pixel with Known Principal Points --- p.30 / Chapter 3.7.2 --- Constant Camera Matrices --- p.31 / Chapter 3.8 --- Experiment --- p.33 / Chapter 3.8.1 --- Experimental Measurement --- p.33 / Chapter 3.8.2 --- Experimental Results --- p.34 / Chapter 3.9 --- Conclusion --- p.37 / Chapter Chapter 4. --- Bundle Adjustment --- p.38 / Chapter 4.1 --- Introduction --- p.38 / Chapter 4.2 --- Descent Direction and Gradient Method --- p.39 / Chapter 4.3 --- Problem Implementation --- p.40 / Chapter 4.4 --- Newton Method --- p.40 / Chapter 4.5 --- Gauss-Newton and Levenberg-Marquardt Method --- p.41 / Chapter 4.6 --- Linear Line Search --- p.43 / Chapter 4.7 --- Golden Section [38] --- p.44 / Chapter 4.8 --- Experiment --- p.47 / Chapter 4.9 --- Summary --- p.50 / Chapter Chapter 5. --- Site Reconstruction Review --- p.51 / Chapter 5.1. --- Introduction --- p.51 / Chapter 5.2. --- Chapter Organization --- p.51 / Chapter 5.3. --- Road Reconstruction --- p.51 / Chapter 5.4. --- Cliff Reconstruction --- p.54 / Chapter 5.5. --- Building Reconstruction --- p.56 / Chapter 5.6. --- Object Assimilation --- p.60 / Chapter 5.7. --- Gallery --- p.61 / Chapter 5.8. --- Application --- p.64 / Chapter Chapter 6. --- Conformal Point Theory --- p.65 / Chapter 6.1. --- Introduction --- p.65 / Chapter 6.2. --- Chapter Organization --- p.65 / Chapter 6.3. --- Hartley Conformal Point Theory --- p.66 / Chapter 6.3.1 --- Angle Measurement Making Use of the Conformal Point --- p.66 / Chapter 6.3.2 --- Position of the Conformal Point --- p.66 / Chapter 6.3.3 --- Proof of the Metric Measurement with the Conformal Point --- p.67 / Chapter 6.3.4 --- Limitation of Hartley's Theory --- p.69 / Chapter 6.4. --- The Discovery of Vanishing Line from 2 or More Images --- p.69 / Chapter 6.4.1 --- Parallax and Plane Stabilization --- p.70 / Chapter 6.4.2 --- Recovery of Vanishing Point by Ideal Plane Stabilization --- p.71 / Chapter 6.5 --- Determining the Infinite Homography and Angle Measurement --- p.73 / Chapter 6.5.1 --- "Four Corresponding Vanishing Points, 3 of which are of Orthogonal Directions" --- p.73 / Chapter 6.5.2 --- "Three Corresponding Orthogonal Point Pairs, and Known Epipoles" --- p.74 / Chapter 6.5.3 --- Known camera matrix and Four Distant Points --- p.74 / Chapter 6.6 --- Applications --- p.77 / Chapter 6.7 --- Conclusion --- p.77 / Chapter 6.8 --- Notes on Publication --- p.78 / Chapter Chapter 7. --- Conclusions --- p.79 / Chapter 7.1 --- Summary --- p.79 / Chapter 7.2 --- Conclusion and Future Work --- p.80 / Appendix A. References --- p.82 / Appendix B. Experiment Dataset --- p.86 / Chapter B.1. --- Introduction --- p.86 / Chapter B.2. --- Synthetic Dataset 1 (S1) --- p.87 / Chapter B.3. --- Synthetic Dataset 2 (S2) --- p.89 / Chapter B.4. --- Real Dataset 1 (Rl) --- p.91 / Chapter B.5. --- Real Dataset 2 (R2) --- p.92 / Chapter B.6. --- Real Dataset 3 (R3) --- p.93 / Appendix C. Mathematical Proof of Vanishing Line Detection by Infinite Plane Stabilization --- p.94
66

Holographic 3D image display : layer-based method and coarse integrated holograms

Chen, Jhen-Si January 2015 (has links)
No description available.
67

Processamento termo-hidro-mecânico da madeira de Eucalyptus Benthamii (maiden e cambage) / Thermo-hydro-mechanical processing of eucalyptus benthamii (maiden e cambage) wood

Martins, Sabrina Andrade 30 April 2015 (has links)
Tese (doutorado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Florestal, Programa de Pós-Graduação em Ciências Florestais, 2015. / A substituição de materiais não renováveis por aqueles à base de madeira é crucial para o desenvolvimento de uma sociedade sustentável. Assim, o desenvolvimento de técnicas e processos termo-hidro (TH) e termo-hidro-mecânico (THM) para madeira pode ser um fator chave neste contexto. O objetivo desse trabalho foi avaliar o uso e a viabilidade de processos TH e THM da madeira, visando melhorar a estabilidade dimensional e encontrar uma alternativa aos processos convencionais de colagem da madeira de Eucalyptus benthamii. Para tanto foi avaliado o efeito de três diferentes tratamentos térmicos nas propriedades da madeira de E. benthamii e verificada a resistência da soldagem sob diferentes parâmetros. Peças de madeira foram submetidas aos seguintes tratamentos: Plato®, Atmosfera inerte e Oléothermie. Para a caracterização do material tratado e não tratado foram determinadas as propriedades físicas (densidade básica, estabilidade dimensional, teor de umidade de equilíbrio, análise física da parede celular e molhabilidade), mecânicas (módulo de ruptura e módulo de elasticidade), colorimétricas (parâmetros colorimétricos L*, a*, b*, C e h*) e químicas (teor de extrativos, teor de lignina e polissacarídeos). Adicionalmente foi avaliada a resistência da soldagem da madeira, determinada por meio do ensaio de cisalhamento e da avaliação da porcentagem de falha na madeira. Além da resistência foram feitos perfis da densidade na linha de soldagem. O tratamento térmico Plato® melhorou a estabilidade dimensional, reduziu a molhabilidade, o módulo de ruptura e o módulo de elasticidade, e tornou a madeira mais escura. As principais alterações na composição química da madeira tratada nesse sistema foram a redução do teor de hemiceluloses e aumento do teor de extrativos. O tratamento térmico em atmosfera inerte melhorou a estabilidade dimensional, reduziu a molhabilidade e o módulo de ruptura, alterou a cor da madeira, tornando-a mais escura, e a composição química da mesma, com a diminuição dos teores de xilose, arabinose e extrativos. O tratamento térmico Oléothermie não afetou a estabilidade dimensional da madeira, no entanto, reduziu o teor de umidade de equilíbrio. Além disso, reduziu a molhabilidade, alterou a cor da madeira, tornando-a mais escura e a sua composição química, reduzindo o teor de xilose e aumentando a proporção de lignina e extrativos. A resistência média obtida na soldagem foi de 10,30 MPa com uma média de 100% de falha na madeira. A densidade na linha de soldagem foi superior ao da madeira, atingindo valores entre 700 e 800 kg/m3. Diante dos resultados obtidos, conclui-se que o processo de soldagem se mostrou viável para a junção de madeira de E. benthamii e que o tratamento térmico pode alterar as propriedades da madeira de E. benthamii, porém depende do método empregado. O tratamento térmico que proporcionou melhora na estabilidade dimensional, e o menor impacto no modulo de ruptura foi o tratamento realizado em atmosfera inerte. / The replacement of non-renewable material by wood-based material is crucial for the development of a sustainable society. Thus, the development of thermo-hydro and thermo-hydro-mechanical processing techniques might be a key factor in such a context. The goal of this study was to evaluate the usefulness and the viability of those processes, aiming to improve the dimensional stability and to find an alternative to the conventional Eucalyptus benthamii wood bonding processes. In order to accomplish that, the effect of heat treatment on the physical (density, dimensional stability, equilibrium moisture content, cell wall physical analysis and wettability), chemical (extractives, lignin and polysaccharides), mechanical (rupture and elasticity modules) and colorimetric (L*, a*, b*, C e h*) properties was evaluated by three different methods: Plato®, inert atmosphere and Oléothermie. The welding strength was also checked under three different sets of parameters. The strengths of the joints were measured in tension shear and through percentage of wood failure. Moreover, the density profile in welded interfaces was also tested. The Plato® treatment improved dimensional stability, decreased wettability, rupture and elasticity modules and made the wood darker. The main changes in chemical composition were the decrease of hemicellulose content and an increase of extractives. The inert atmosphere treatment improved dimensional stability, decreased wettability and the rupture module, changed wood color, making it darker and changed its chemical composition as well, decreasing xylose, arabinose and extractives values. The Oléothermie treatment did not affect dimensional stability. However, it decreased the equilibrium moisture content and wettability, made the wood darker and changed its chemical composition, decreasing the xylose value and increasing the lignin and extractives rates. The mean strength obtained in welding was 10,30 MPa with 100% wood failure. The welding interface density was superior than that of the wood, attaining maximal values between 700 and 800 kg/m3. Given the results, we conclude that the welding process proved feasible for E. benthamii wood joining and that the heat treatment can change its physical, mechanical, chemical and colorimetric properties, depending on the method employed.
68

3D object reconstruction from 2D and 3D line drawings.

January 2008 (has links)
Chen, Yu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 78-85). / Abstracts in English and Chinese. / Chapter 1 --- Introduction and Related Work --- p.1 / Chapter 1.1 --- Reconstruction from 2D Line Drawings and the Applications --- p.2 / Chapter 1.2 --- Previous Work on 3D Reconstruction from Single 2D Line Drawings --- p.4 / Chapter 1.3 --- Other Related Work on Interpretation of 2D Line Drawings --- p.5 / Chapter 1.3.1 --- Line Labeling and Superstrictness Problem --- p.6 / Chapter 1.3.2 --- CAD Reconstruction --- p.6 / Chapter 1.3.3 --- Modeling from Images --- p.6 / Chapter 1.3.4 --- Identifying Faces in the Line Drawings --- p.7 / Chapter 1.4 --- 3D Modeling Systems --- p.8 / Chapter 1.5 --- Research Problems and Our Contributions --- p.10 / Chapter 1.5.1 --- Recovering Complex Manifold Objects from Line Drawings --- p.10 / Chapter 1.5.2 --- The Vision-based Sketching System --- p.11 / Chapter 2 --- Reconstruction from Complex Line Drawings --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Assumptions and Terminology --- p.15 / Chapter 2.3 --- Separation of a Line Drawing --- p.17 / Chapter 2.3.1 --- Classification of Internal Faces --- p.18 / Chapter 2.3.2 --- Separating a Line Drawing along Internal Faces of Type 1 --- p.19 / Chapter 2.3.3 --- Detecting Internal Faces of Type 2 --- p.20 / Chapter 2.3.4 --- Separating a Line Drawing along Internal Faces of Type 2 --- p.28 / Chapter 2.4 --- 3D Reconstruction --- p.44 / Chapter 2.4.1 --- 3D Reconstruction from a Line Drawing --- p.44 / Chapter 2.4.2 --- Merging 3D Manifolds --- p.45 / Chapter 2.4.3 --- The Complete 3D Reconstruction Algorithm --- p.47 / Chapter 2.5 --- Experimental Results --- p.47 / Chapter 2.6 --- Summary --- p.52 / Chapter 3 --- A Vision-Based Sketching System for 3D Object Design --- p.54 / Chapter 3.1 --- Introduction --- p.54 / Chapter 3.2 --- The Sketching System --- p.55 / Chapter 3.3 --- 3D Geometry of the System --- p.56 / Chapter 3.3.1 --- Locating the Wand --- p.57 / Chapter 3.3.2 --- Calibration --- p.59 / Chapter 3.3.3 --- Working Space --- p.60 / Chapter 3.4 --- Wireframe Input and Object Editing --- p.62 / Chapter 3.5 --- Surface Generation --- p.63 / Chapter 3.5.1 --- Face Identification --- p.64 / Chapter 3.5.2 --- Planar Surface Generation --- p.65 / Chapter 3.5.3 --- Smooth Curved Surface Generation --- p.67 / Chapter 3.6 --- Experiments --- p.70 / Chapter 3.7 --- Summary --- p.72 / Chapter 4 --- Conclusion and Future Work --- p.74 / Chapter 4.1 --- Conclusion --- p.74 / Chapter 4.2 --- Future Work --- p.75 / Chapter 4.2.1 --- Learning-Based Line Drawing Reconstruction --- p.75 / Chapter 4.2.2 --- New Query Interface for 3D Object Retrieval --- p.75 / Chapter 4.2.3 --- Curved Object Reconstruction --- p.76 / Chapter 4.2.4 --- Improving the 3D Sketch System --- p.77 / Chapter 4.2.5 --- Other Directions --- p.77 / Bibliography --- p.78
69

A proteomic study of Pseudomonas putida by two-dimensional gel electrophoresis : establishing quantitative standards for intra-laboratory results /

Fowlkes, Kelly. January 2007 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (leaves 66-68).
70

Homotopy string links over surfaces

Yurasovskaya, Ekaterina 11 1900 (has links)
In his 1947 work "Theory of Braids" Emil Artin asked whether the braid group remained unchanged when one considered classes of braids under linkhomotopy, allowing each strand of a braid to pass through itself but not through other strands. We generalize Artin's question to string links over orientable surface M and show that under link-homotopy surface string links form a group PBn(M), which is isomorphic to a quotient of the surface pure braid group PBn(M). Surface braid groups and their properties are an area of active research by González-Meneses, Paris and Rolfsen, Goçalves and Guaschi, and our work explores the geometric and visual beauty of this subject. We compute a presentation of PBn(M) in terms of the generators and relations and discuss the orderability of the group in the case when the surface in question is a unit disk D.

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