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In this thesis, a load path caused by arching action in reinforced concrete slabs is described and validated using a three-dimensional model. Currently, the CHBDC enforces a 4 meter girder spacing requirement in the design of deck slabs. The aim of this thesis is to investigate the load path induced by arching action in deck slabs with a wide range of girder spacing. To do this, a two-dimensional model was developed to examine the path of horizontal stress and was validated using a FEM. A parametric study showed that girder spacing does not affect the development of restraining stress while cantilever width does. As well, cracking of the slab is necessary for arching action to occur. These results help with future development of a rational model to be used by bridge designers.

<p>In this day and age when 3D cinema is ever increasing in popularity and 3D television sets on the verge of becoming a reality in our homes, the media production companies are interested in looking at how they can start producing stereoscopic format media for this exciting medium. This thesis proposes a solution to parts of the stereoscopic production pipeline by examining and proposing the extent of the requirements of a plug-in to aid in the setting up and rendering of stereo pairs and ultimately proposing such a plug-in and modifying it to suit the proposed requirements. With a high emphasis on ensuring that the plug-in is capable of producing enjoyable stereoscopic content, the plug-in is tested by rendering a demanding scene previously used in factual production work. The findings of these tests ultimately lead to the evaluation of the plug-ins usefulness as a tool for not only the production studio involved but for anyone interested in generating material for this exciting medium.</p>

ABSTRACT Three-dimensional modeling on the aerodynamics of airflow and diffusion of air pollutants in a longitudinal-ventilated traffic tunnel was carried out. The model takes ventilation fans, traffic flow rate, speed, emission factor and piston effect of moving vehicles into consideration. Turbulent flow and dispersion of gaseous pollutants in road tunnels were solved numerically using the finite volume method. Traffic emissions were accordingly modeled as banded line sources along the tunnel floor. The effects of fan ventilation, roughness and piston effect of moving vehicles on the air flow and pollutant dilution are examined. Concentrations of gaseous pollutants CO, NOX, SO2 and THC (total hydrocarbons) at three axial locations in the tunnel, together with traffic flow rate, traffic speed and types of vehicle were measured. Case study was conducted on the Cross-Harbor Tunnel and the Chungcheng Tunnel in which on-site measurements of traffic flow were also conducted concurrently to provide traffic emission data to the tunnel environment for numerical simulation and comparisons. The aim of this study was to understand the spatial variation of air pollutants generated by traffic emissions and evaluation of ventilation performance and piston effect of moving vehicles on dilution of air pollutants in these tunnels. The results show that the major emission sources of CO are passenger cars and motorcycles, while major emission sources of NOx are trucks. Pollutants convect downstream with the wind generated either by longitudinal ventilation fans and/or moving vehicles, thus causing increasing pollutants concentrations with increasing downstream distance. The piston effect of moving vehicle alone can provide 64% ~ 85% increase of wind speed in Chungchen Tunnel and 13% ~ 20% in Cross-Harbor Tunnel. When all fans are on, showing 185% ~ 328% and 120% ~ 182% increases in Chungchen Tunnel and Cross-Harbor Tunnel, respectively. The piston effect of moving vehicle alone can provide 14% ~ 32% dilution of air pollutants in the Chungcheng Tunnel. The piston effect of moving vehicles is compounded with ventilation fans, showing a 47% ~ 66% dilution effect when all fans are on. For the Cross-Harbor Tunnel, the piston effect of moving vehicle alone can provide 9% ~ 23% dilution of air pollutants and 36% ~ 74% dilution effect when all fans are on. The results reveal that cross-sectional concentrations are non-uniformly distributed and that concentrations rise with downstream distance. When all fans were turned off, wind speed in tunnels would be considered as constant, and gaseous pollutants concentration agree with linearly alone the tunnel.

In this thesis, a load path caused by arching action in reinforced concrete slabs is described and validated using a three-dimensional model. Currently, the CHBDC enforces a 4 meter girder spacing requirement in the design of deck slabs. The aim of this thesis is to investigate the load path induced by arching action in deck slabs with a wide range of girder spacing. To do this, a two-dimensional model was developed to examine the path of horizontal stress and was validated using a FEM. A parametric study showed that girder spacing does not affect the development of restraining stress while cantilever width does. As well, cracking of the slab is necessary for arching action to occur. These results help with future development of a rational model to be used by bridge designers.

In this day and age when 3D cinema is ever increasing in popularity and 3D television sets on the verge of becoming a reality in our homes, the media production companies are interested in looking at how they can start producing stereoscopic format media for this exciting medium. This thesis proposes a solution to parts of the stereoscopic production pipeline by examining and proposing the extent of the requirements of a plug-in to aid in the setting up and rendering of stereo pairs and ultimately proposing such a plug-in and modifying it to suit the proposed requirements. With a high emphasis on ensuring that the plug-in is capable of producing enjoyable stereoscopic content, the plug-in is tested by rendering a demanding scene previously used in factual production work. The findings of these tests ultimately lead to the evaluation of the plug-ins usefulness as a tool for not only the production studio involved but for anyone interested in generating material for this exciting medium.

Drug delivery systems (DDS) are essentially pharmaceutical products for human therapy, typically involving a mixture of active ingredients and excipients. Based upon quantitative characterization of structure, the thesis introduces the concept of classifying the architecture of DDS into four levels by their spatial scale and the life time period. The primary level is recognised as the static structure of the whole dosage form with a size from μm to cm with the final structure generated by formulation design. The secondary level categorises the structures of particles or sub-units to form a DDS with sizes from nm to mm as key units in processing such as mixing, grinding, granulation and packing; The tertiary level represents the dynamic structures of DDS during the drug release phase in vitro or in vivo incorporating the structure size range from nm to mm, which undergo changes during dissolution, swelling, erosion or diffusion. The spatial scale for the quaternary level is defined as the meso or micro scale architecture of active and non-active molecules within a DDS with sizes from Å to μm for the molecular structure of drug and excipients. Methods combining X-ray tomography, image processing, and 3D reconstructions have been devised and evaluated to study systematically pharmaceutical structures and correlate them with drug release kinetics of DDS. Based on the quantitative structural information of pharmaceutical intermediates and dosage forms, it is possible now to correlate structures with production processing, behaviour and function, and the static and dynamic structures of DDS with the release kinetics. Thus, a structure-guided methodology has been established for the research of DDS. / Chinese Academy of Sciences

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