The purpose of this research is to investigate the relationships between the movement time, travel speed and occupant density during trial evacuations, particularly for theatre-type rooms. The study mainly focuses on crowd movement behaviour within a restricted space and covers aspects of human behaviour and issues needed to be considered in terms of the characteristics of lecture theatres. A set of experiments were carried out in three building blocks at the University of Canterbury in order to obtain the actual data for analysis. The number of students evacuating from each exit and the evacuation time were recorded, and their movement behaviour was monitored by video camera. Based on the experimental data, a numerical analysis was undertaken to formulate an equation for the prediction of evacuation time applying to lecture theatres. The developed equation was compared with other available relationships from the literature. An evacuation model under development, named EvacuatioNZ, was applied to simulate the experiments and the results were compared with the experimental data. The comparison showed that the developed equation showed a better performance in predicting evacuation time of lecture theatres than other available methods however, had some limitations. The EvauctioNZ model was able to be improved by using an alternative geometry input but was still not as accurate as the developed method. A recommended modification of the model was presented for improvement.

No description available.

No description available.

X-ray imaging exams are widely used procedures in medical diagnosis. Whenever an x-ray imaging procedure is performed, it is accompanied by scattered radiation. Scatter is a significant contributor to the degradation of image quality in breast CT. This work uses our understanding of the physics of Compton scattering to overcome the reduction in image quality that typically results from scattered radiation. By measuring the energy of the scattered photons at various locations about the object, an electron density (ρe) image of the object can be obtained. This work investigates a system modeled using a 2D cross-sectional view of a breast CT geometry. The ρe images can be obtained using filtered backprojection over isogonic curves. If the detector has ideal energy and spatial resolution, a single projection will enable a high quality image to be reconstructed. However, these ideal characteristics cannot be achieved in practice and as the detector size and energy resolution diverge from the ideal, the image quality degrades. To compensate for the realistic detector specifications a multi-projection Compton scatter tomography (MPCST) approach was introduced. In this approach an x-ray source and an array of energy sensitive photon counting detectors located just outside the edge of the incident fan-beam, rotate around the object while acquiring scattering data. The ρe image quality is affected by the size of the detector, the energy resolution of the detector and the number of projections. These parameters, their tradeoffs and the methods for the image quality improvement were investigated. The work has shown that increasing the energy and spatial resolution of the detector improves the spatial resolution of the reconstructed ρe image. These changes in the size and energy resolution result in an increase in the noise. Thus optimizing the image quality becomes a tradeoff between blurring and noise. We established that a suitable balance is achieved with a 500 eV energy resolution and 2×2 mm2 detector. We have also established that using a multi-projection approach can offset the increase in the noise.

Intent and aim The primary intent of this thesis is to explore about Compact Urbanism and to define an approach towards low density, mono functional precincts in the city that lie underutilized in their potential towards a positive contribution to the city and to come with new model of compact city that will answer the challenges and problems that are still unanswered. The reconfigured Compact city will built environment at the best possible way to support the best quality of life. Everyone wants to be free of the urban pollution he can directly sense: the smog, smoke, grime, litter, odors, city heat, din, poor water, and the slum conditions. But the environmental degradation associated with urban development can also be measured in terms of disrupted ecosystems and wasteful use of green space and natural resources. The approach illustrates how and why compact city is the way of redesigning an urban environment so as to get rid of these negative aspects and to preserve enhance the qualities of urban life that we have come to accept desirable. Eventually to reconfigure the compact city which will work better than what has been proposed so far. The new model of compact city will make neighborhoods more lively, safe and relevant for children; and so that the city itself becomes a more exciting center for personal interactions in today’s fast-moving world. Main Concerns Concerns rise from the observations that there are city structures that are inefficient and are underutilized areas in the cities which have lower intensity of use and untapped potential to absorb new functions, activities and housing stocks. As of by-product of mono functional use and low density these areas have issues like lack of identity, character and lack of a vibrant public domain. A Renewal process is important for such city precincts that are located near city centers or work centers and occupy large areas at low densities in relation to its location and potential. The notion of the Compact City is a reaction against the city structures in most developed cities-dense cores accommodating most of the cities workplaces, retail, entertainment, commerce, services and amenities and sprawling low-density, single use suburbs-a city structure which by default produces the need to travel and as a product car dependency, energy consumption and pollution. The basis for the debate is the general agreement that the city as we know and inhabit today causes unsustainable environmental stress, is socially stratified & functionally sub-optimal, and is expensive to run.  Challenges The city is a platform where humans meet, interact, collaborate, exchange their views, make new relationship, work and compete with each other. City forms a shell in which all lives survive and develop. It moulds their lives. It is a web where different kind of people varies in religion, ethnicity and race lives together. It interlocks them and makes a mass of variety of living and nonliving objects. All cities are fast growing. People are moving in and out of the cities. Each day somebody is transferred to some other place. Families are breaking up either of transfers of job or splitting of parents. New constructions are planning. Whether the new construction is required or not people are building it up without giving a thought how it will be beneficial to the environment. Because of all these impacts of improper planning, land value in the city is hiking up and eventually people are left with no option but to move outskirts of the city. New tracts of land are occupying. Green places are disappearing. The challenge has to do with conservation. The fast growing encroachment towards the countryside of the city is destroying valuable green fields. They are affecting the farm lands which are essential for human life in order to get food for unstoppable population. There is a need of getting control over the growth of the city. There should be more functional and organized planning which can curtail sprawl. We have to comprehend the significance of land as it is not infinitive, it is limited. The city should be redesigned or proper measures and consideration are to be made in order to conserve land, water, energy and waste. If irregular spreading of city is not stopped and compact cities are not implemented than we will lose valuable lands and will not be able to acquire benefits of natural environment as it will be destructed. Compactness has to be achieved to build environment to support best quality of life. / Literature survey -- Methodology -- Case studies -- Social implications of compact city -- Compact city guiding principles. / Department of Architecture

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No description available.

Switched reluctance motors with fully pitched windings are a relatively recent advancementin motor technology having only been in existences ince the early 1990's. They have been shown previously to offer greater torque per unit copper loss, and hence higher torque density, than conventional switched reluctance machines with short pitched windings. Early work by Mecrow and Barrass has demonstrated operation of prototype machines, developed and assessedv arious methods of control strategy, and made some comparisons of machine efficiency and inverter rating. The results presented here build on this early work by, in essence, examining the aspects of machine design, control strategy and inverter topology that affect drive performance and cost. Detailed comparisons of inverter rating and machine efficiency are made under equal conditions with the various methods of excitation that are possible. This is achieved with results from a test rig, including temperature rise tests, and the use of accurate dynamic simulation. The latter is developed to accurately model the motor with its strong mutual coupling between phases, various inverter topologies and the details of the controller such as digital PWM. As a result comparisons between simulated and measured results are shown to be very good. The fundamentals of machine design are examined with a view to optimising the machine for fully pitched windings. Previous work has indicated that good results are achieved when a conventional machine is simply rewound, however it is shown that further improvements can be made. Proposals are made to improve the drive in terms of both machine performance and power electronic rating. A search method is proposed that optimises current waveshape for either maximum torque per unit copper loss, or smooth torque for lowest loss. The method works over the entire speed range, as the rate of change of flux linkage is taken into account. Three alternative power electronic converters are developed, one of which is also particularly suitable for the short pitched winding machine. Aspects of silicon rating, current controllability, and current sensor requirements are discussed.

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The properties of a new family of carbon structures based on stacked cyclic C6 rings and intercalated cyclic C6 structures: (C6)n and (C6)nMen-1 have been studied theoretically using ab initio DFT (Density Functional Theory). Calculations of the structural, electronic, and vibrational properties of a range of these molecules have been carried out using DFT techniques with the best correspondence to experimental results. The chemical and structural stability of structures based on stacks of cyclic C6 has also been estimated for pure carbon molecules (C6)n and for metal-organic sandwich molecules intercalated with Fe and Ru atoms. These have (C6)nFen-1 and (C6)n Run-1 compositions, respectively These structures are predicted to show a variety of new electronic, vibrational and magnetic properties. Ultra-small diameter tubular molecules are also found to have unique rotational electron states and high atomic orbital pi-sigma hybridization giving rise to a high density of electron states. All phonons in these structures have collinear wave vectors leading to an ultrahigh density of phonon states in dominant modes suggesting that some of these structures may exhibit superconductivity. These properties, as well as a predicted high electron mobility, make these structures promising as components in nanoelectronics. Experiments using femto-second laser pulses for the irradiation of organic liquids suggest that such structures may appear under certain conditions. In particular, a new type of iron carbide has been found in these experiments.