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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.
361

New systems for heterogeneous catalytic epoxidation

Ho-Hune, Patricia January 2005 (has links)
Epoxides are very useful key intermediates in the construction of synthetically challenging molecules. Owing to their strategic importance in organic synthesis, novel polymer-supported iminium salts were investigated for the catalytic oxidation of unfunctionalised alkenes. A solid-phase methodology was initiated and then developed for the evaluation of several heterogeneous catalysts. In an initial approach, immobilised iminium salts were prepared by condensation of 2-(bromoethyl)benzaldehyde with commercially available aminomethyl resins. These materials were shown to be able to successfully catalyse the epoxidation of 1-phenylcyclohexene. The epoxidation reactions were performed in a triphasic system using Oxone® as the oxidising agent and 25 mol% of the catalyst. For all the resin type employed, namely NovaSyn TG, NovaGel, ArgoGel or PEGA, complete conversion of the alkenes to their respective epoxides was obtained.
362

An investigation of the 'soft' features of sustainable and healthy housing design : exploring stakeholder preferences and their provision in new housing developments

Prochorskaite, A. January 2016 (has links)
Despite the widely recognised importance of the impact that built environment has on health and well-being, the concept of sustainable housing is still regarded largely in terms of environmental sustainability. However, given the urgent need to increase the quantity and sustainability of new homes in the UK, it is essential that the design and delivery of sustainable housing does not neglect health and well-being aspects that are essential for enhancing the quality of life and the development of sustainable communities. This study focuses on the ‘soft’ features of sustainable housing, that is, the non-technological components of housing and neighbourhood design that can affect occupants’ health and well-being as well as their satisfaction with their homes. The research aims to conceptualise and identify these ‘soft’ features of housing design and establish whether the opinions of housing users regarding their importance are aligned with those of the housing providers. Using a case study approach, the study also assesses the extent to which such features are being provided by new housing developments. The research begins with a review of literature of the sustainable housing and healthy housing concepts, which lead to the development of a framework for sustainable housing design with an emphasis on health and well-being. Building on this foundation, three phases of the methodology were developed to address the aims of the research: Firstly, a content analysis of sustainable housing standards is carried out, followed by a survey to ascertain the relative importance that housing stakeholders attach to these ‘soft’ features, and lastly, six housing developments are evaluated with regards to their provision of these features. The findings reveal that housing user preferences are not always aligned with those of housing providers, and indeed, a number of notable differences in opinion are also found between the private sector and social housing providers. Lastly, assessment of the six case studies indicates a low level of provision of such features new housing developments. These findings indicate that a more comprehensive approach is necessary for addressing and providing for the softer features of housing and neighbourhood design.
363

A computerized tendering model for the civil engineering construction company.

January 1984 (has links)
by Zen Wei-peu. / Bibliography : leaf 112 / Thesis (M.B.A.)--Chinese University of Hong Kong, 1984
364

Material control information system: construction industry : research report.

January 1981 (has links)
by Choi Wai-ming. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1981. / Bibliography: leaves 134-135.
365

Computer modeling and analyses of multisection distributed feedback lasers.

January 1995 (has links)
by So-kuen C. Liew. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves [40-45, 3rd gp.]) and index. / Abstract --- p.ii / Acknowledgments --- p.iv / Table of Contents --- p.v / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Distributed Feedback Lasers --- p.1 / Chapter 1.2 --- Computer Model --- p.6 / Chapter 1.3 --- Analyses --- p.8 / Chapter 1.4 --- Organization of Thesis --- p.11 / Chapter 2 --- Computer Model --- p.13 / Chapter 2.1 --- Comparison of Theoretical Models --- p.15 / Chapter 2.2 --- Assumptions and Approximations --- p.17 / Chapter 2.2.1 --- Longitudinal Spatial Hole Burning --- p.17 / Chapter 2.2.2 --- Spontaneous Emission --- p.18 / Chapter 2.2.3 --- Nonlinear Gain Saturation --- p.19 / Chapter 2.2.4 --- Carrier-Induced Index Change --- p.20 / Chapter 2.2.5 --- Single-mode Operation Assumption --- p.22 / Chapter 2.2.6 --- Otbers --- p.22 / Chapter 2.3 --- Theories and Approaches --- p.25 / Chapter 2.3.1 --- Coupled Wave Theory --- p.25 / Description --- p.25 / Stop-Band --- p.29 / Second-Order DFB Laser --- p.30 / DFB Designs To Improve SMSR --- p.30 / Chapter 2.3.2 --- Transfer Matrix Approach --- p.32 / Chapter 2.4 --- Above-Threshold Model --- p.34 / Chapter 2.4.1 --- Introduction --- p.34 / Chapter 2.4.2 --- Formalism --- p.36 / Facet Output Power and Optical Spectrum --- p.39 / Photon Density Distribution --- p.41 / Variance of Photon Density Distribution --- p.42 / Nearfield Distribution --- p.42 / Surface Emission --- p.43 / Power-Current Characteristics --- p.44 / Optical spectrum --- p.45 / Subthreshold Analysis --- p.47 / Linear Yield Analysis --- p.47 / Chapter 2.4.3 --- Computer Implementation --- p.48 / Flowchart --- p.48 / Subroutines --- p.52 / "Runtime, Numerical Stability" --- p.56 / Chapter 2.5 --- "Discussion,Summary and Future Work" --- p.59 / Chapter 2.5.1 --- Validation of the DFB Model --- p.59 / Chapter 2.5.2 --- Summary --- p.67 / Chapter 2.5.3 --- Topics for Future Work in Theoretical Modeling --- p.68 / Chapter 3 --- Analysis of DFBDBR Laser --- p.72 / Chapter 3.1 --- Introduction --- p.72 / Chapter 3.2 --- Subthreshold Analysis --- p.78 / Chapter 3.2.1 --- Introduction --- p.78 / Chapter 3.2.2 --- Results --- p.81 / Symmetric End-Sections --- p.81 / Asymmetric End-Sections --- p.85 / Chapter 3.3 --- Above-threshold Analysis --- p.88 / Chapter 3.3.1 --- Analysis --- p.89 / Chapter 3.3.2 --- Length Ratio --- p.92 / Chapter 3.3.3 --- Design Plot --- p.99 / Chapter 3.3.4 --- Longitudinal Spatial Hole Burning --- p.102 / Chapter 3.3.5 --- Effective Linewidth Enhancement Factor --- p.104 / Chapter 3.3.6 --- Asymmetric DFBDBR --- p.107 / Chapter 3.4 --- Conclusion --- p.109 / Chapter 4 --- Analysis of Complex-Coupled DFB --- p.110 / Chapter 4.1 --- Introduction --- p.110 / Chapter 4.2 --- Laser Structure --- p.113 / Chapter 4.2.1 --- Grating Layer --- p.114 / Chapter 4.2.2 --- Parameter Values --- p.119 / Chapter 4.3 --- Above-Threshold Analysis of CCDFB --- p.122 / Chapter 4.3.1 --- Threshold Current --- p.122 / Grating Duty Cycle = 0.36 --- p.122 / Grating Duty Cycle = 0.15 --- p.128 / Chapter 4.3.2 --- Power Efficiency --- p.131 / Grating Duty Cycle = 0.36 --- p.131 / Grating Duty Cycle = 0.15 --- p.136 / Chapter 4.3.3 --- Summary --- p.137 / Chapter 4.4 --- Yield Analysis of LCDFB and QWDFB --- p.138 / Chapter 4.4.1 --- Introduction --- p.138 / Chapter 4.4.2 --- Method --- p.140 / Chapter 4.4.3 --- Results --- p.141 / Facet Phase Angle --- p.141 / Quarterwave Phase-Shifted DFB Laser --- p.144 / Loss-Coupled DFB Laser --- p.148 / Chapter 4.5 --- Conclusion --- p.154 / Chapter 5 --- Summary and Conclusion --- p.157 / Chapter 5.1 --- Summary --- p.157 / Chapter 5.1.1 --- Summary of Major Contributions --- p.157 / Chapter 5.1.2 --- Summary of Modeling and Validation --- p.159 / Chapter 5.1.3 --- Summary of Model Applications --- p.160 / DFBDBR Laser --- p.161 / Loss-Coupled DFB Laser --- p.162 / Chapter 5.2 --- Topics for Future Studies --- p.163 / References --- p.R-l / Appendices --- p.A-l / Chapter A. --- Derivations --- p.A-l / Chapter A.1 --- Noise Power --- p.A-l / Chapter A.2 --- Product of Field Vector and Its Adjoint --- p.A-2 / Chapter A.3 --- Gain-Coupling Coefficient --- p.A-5 / Chapter B. --- Subroutines in Computer Program --- p.A-8 / Chapter B.l --- Subroutines in 'drive.f' --- p.A-8 / Chapter B.2 --- Subroutines in 'Core.f' --- p.A-9 / Chapter B.3 --- Subroutines in 'initiaLf' --- p.A-13 / Chapter B.4 --- Subroutines in ´بmisc.f' --- p.A-14 / Chapter C. --- List of Figures --- p.A-17 / Chapter D. --- List of Tables --- p.A-22 / Chapter E. --- List of Abbreviations and Acronyms --- p.A-23 / Chapter F. --- List of Symbols --- p.A-24 / Chapter G. --- List of Publications --- p.A-27 / Index --- p.I-1
366

Wireless broadcast with physical-layer network coding. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Feng, Shen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 84-88). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
367

Multi-spectra artificial compound eyes, design, fabrication and applications. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Yao, Yupei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 58-60). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
368

Pocket-type reinforced brickwork retaining walls

Tellett, John January 1984 (has links)
From the literature survey it is clear that reinforced brickwork pocket type retaining walls are a well established form of construction in the USA, however, only a small number have been built in the UK. This is surprising since coat studies have consistently indicated that pocket type construction la more economical than fair-faced concrete walls. The available and forthcoming design guidance on reinforced brickwork is reviewed. The main aim of this research was to Investigate the structural performance of pocket type walls in relation to the requirement of the Draft Code for Reinforced Masonry. Reported within are the method and results of an experimental research programme. In all six walls and fifteen beams were tested. The parameters examined were brick type, percentage of reinforcement, slenderness and shear span ratio. Flexural failure occurred in all the walls and in the medlum-1ightly reinforced beams whilst only the heavily reinforced beams failed in shear. The experimental results were predicted accurately when analysed using the flexural design equations in the Draft Code. However the Code requirements for shear appear to be unduly conservative. Concurrent with the experimental work a finite element program was developed to analyse pocket type walls. In spite of the many assumptions made in the modelling of material properties there was good agreement between analytical and experimental results. Subsequently a parametric survey was undertaken. The variables selected for examination were slenderness, pocket spacing, panel thickness percentage of reinforcement and arching action in the panels. Both rectangular and flanged sections were investigated. The results indicated that the Draft Code gave good predictions when flexural failure of the stem occurred. But when panel failure developed neither yield line analysis nor arching theory was able to predict collapse. Guidance is given on the sizing of panels. It is concluded that pocket type walls, when designed to the requirements of the Draft Code, perform adequately at serviceability and ultimate design loads for pocket spacings up to 1.0m. Further experimental work is necessary to establish whether the guidance given in the Code is applicable to walls with pocket spacings greater than 1.0m.
369

The changing use of materials in construction of the vernacular Thai house

Punpairoj, Poomchai January 2013 (has links)
Due to the processes of modernization, the existing traditional Thai houses have been changed from tradition to contemporary. Contemporary vernacular houses in the central Thailand are categorised as transforming and reproduction houses. This study focused on three types of vernacular houses in the central region: the traditional Thai house; the transforming Thai house; and the reproduction Thai house. This study examined the features in these contemporary vernacular houses which have been influenced by changing use of materials and construction methods. The study was conducted by examining the changes of vernacular houses in three locations in Ayutthaya province: the urban district village, the rural village and the motorway buffer area. Data were collected with the uses of materials, construction types, and features of construction elements. The data obtained were analyzed and discussed through typological analysis and constant comparative analysis to reveal the differences of vernacular houses among the studied locations. The findings show the ways in which vernacular traditions have been integrated with modern influences. The development and change of use of materials are indicated for reflecting the evolution of vernacular Thai houses. The results reveal that, from the earliest period of modern Thai industry, contemporary vernacular Thai housing has been influenced by materials available and construction methods employed. Industrial materials have been used to improve the performance and change the appearance of the traditional Thai houses. Because of the availability of early industrial materials and construction methods, the transforming Thai houses will therefore continue to be sustained by their current owners. Traditional and modern materials are applied to the reproduction Thai houses with updated construction techniques. Vernacular Thai houses are confirmed as a continuous process and appreciated in the context of the present. The results of this study offers some clues to support an understanding of living heritage, and thus promoting conservation of vernacular buildings in Thailand.
370

Precast-prestressed building systems and elements

Hyde, Douglas W. January 2010 (has links)
Typescript, etc. / Digitized by Kansas Correctional Industries

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