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Computational imaging presents opportunities to overcome conventional imaging limits, such as a trade-off between image resolution and system z-height. Optical design and image processing are developed in parallel to optimise imaging system properties for a given application. These properties can be quantified and it is shown that the image quality of a multichanneled imaging system, relying on superresolution (SR) image reconstruction, is dependent on object depth due to interference of sampling phases. A novel multichannel imaging system that does not rely on SR reconstruction, yet achieves a reduction of system height by a factor of two, is presented. The mitigation of SR reconstruction reduces computational effort, offering an attractive option for a computational imaging device in the mobile handset market. The image reconstruction framework required for the reduced height multichanneled imager is proposed in a general form so that it is applicable to many multi-aperture geometries, making it compatible with commercial interests, i.e. it is sensible to develop something with a wide application space. A second novel imaging system is also described in this thesis: A snapshot hyperspectral imaging (HSI) camera, comprising of a square array of miniature camera modules, makes use of the multiple imaging channels to record spectrally distinct images. The generalised image processing framework is applied to the image reconstruction problem to generate the spectral data-cubes. This approach to hyperspectral imaging presents opportunities to gain performance advantages over other snapshot HSI technologies and do so at a significant reduction in cost.

This thesis investigates the use of X-ray Excited Optical Luminescence (XEOL) and Time Resolved X-ray Excited Optical Luminescence (TR XEOL) within the Earth sciences. The project contains two primary objectives, the first of which is the design and building of a high-resolution luminescence spectroscopy facility. This includes the installation and commissioning of the facility on the I18 microfocus beamline at Diamond, the UK's national synchrotron facility. In describing the system's design and commissioning, I explore many implications of the technique. The second objective is using this new facility to investigate a suite of minerals to develop new analytical techniques utilizing XEOL and TR XEOL spectroscopy for applications within the Earth sciences. An aspect of this investigation is to explore the potential of Time Resolved Optically Derived X-ray Absorption Spectroscopy (TR OD XAS) of substitute trace elements in minerals. To date CW OD XAS has been shown to have very limited application within the Earth sciences. (Soderholm et al., 1998-120) The thesis explores differences between photoluminescence (PL) and XEOL responses in mineral systems, and investigates how these differences can be exploited. Luminescence, the phenomenon upon which the thesis is based, is a complex and poorly utilised phenomena within Earth sciences, it is however, orders of magnitude more sensitive, than many of the more accepted techniques used for the detection of trace elements, on this basis alone I would suggest it deserves further consideration. Luminescence techniques have developed much further in other disciplines; I therefore have incorporated many descriptions, models, and interpretations from other disciplines in order to identify methodologies and techniques that have the potential to be utilized in the study and interpretation of luminescence within the Earth sciences. The thesis demonstrates that luminescence in minerals with measured lifetimes, as fast as ~ 20 ps exist. Previously the recorded luminescent lifetimes, for minerals, in the literature are measured in ns. This finding leads to the novel concept that the measurement of TR XEOL with ps resolution combined with the measurement of the intensity of a luminescent signal as a function of excitation can provide significant new insights into the nature of the emission and the luminescent processes. I explore and demonstrate the potential of using dose dependence techniques of continuous wave and TR XEOL as a new analytical technique. I also demonstrate the use of a technique used extensively within Biology has an application with Earth sciences. The methodology incorporates the calculation of the natural lifetime of an emission through the relationship between the absorption and emission coefficients. (Strickler and Berg, 1962). I discuss how knowledge of the natural lifetime of an emission allows quantification of luminescence through measurement of a modified lifetime of emission. The quantification of a luminescent emission has significant potential within the geosciences one example being the identification of disputed emissions. I also consider the potential to use TR XEOL techniques in mapping complex heterogeneous rocks and minerals.

This research addresses the problem of populating Building Information Model databases with information on building construction materials using a new classification method which uses multi-spectral laser scanning intensity and geometry data. Research in multi-spectral laser scanning will open up a new era in survey and mapping; the 3D surface spectral response sensitive to the transmitted wavelengths could be derived day or night in complex environments using a single sensor. At the start of this research a commercial multi-spectral sensor did not exist, but a few prototype level instruments had been developed; this work wished to get ahead of the hardware development and assess capability and develop applications from multi-spectral laser scanning. These applications could include high density topographic surveying, seamless shallow water bathymetry, environmental modelling, urban surface mapping, or vegetative classification. This was achieved by using from multiple terrestrial laser scanners, each with a different laser wavelength. The fused data provided a spectral and geometric signature of each material which was subsequently classified using a supervised neural network. The multi-spectral data was created by precise co-positioning of the scanner optical centres and sub-centimetre registration using common sphere targets. A common point cloud, with reflected laser intensity values for each laser wavelength, was created from the data. The three intensity values for each point were then used as input to the classifier; ratios of the actual intensities were used to reduce the effect of range and incidence angle differences. Analysis of five classes of data showed that they were not linearly separable; an artificial neural network classifier was the chosen classifier has been shown to separate this type of data. The classifier training dataset was manually created from a small section of the original scan; five classes of building materials were selected for training. The performance of the classification was tested against a reference point cloud of the complete scene. The classifier was able to distinguish the chosen test classes with a mean rate of 84.9% and maximum for individual classes of 100%. The classes with the highest classification rate were brick, gravel and pavement. The success rate was found to be affected by several factors, among these the most significant, inter-scan registration, limitation on available wavelengths and the number of classes of material chosen. Additionally, a method which included a measure of texture through variations in intensity was tested successfully. This research presents a new method of classifying materials using multi-spectral laser scanning, a novel method for registering dissimilar point clouds from different scanners and an insight into the part played by laser speckle interpretation of reflected intensity.

The questions that this project poses are centred on an examination of photography's relationship to modernist architectural space. Polarising the melancholic and the utopian, the definition of photography is extended to include its manifestation across a number of diverse sites and processes. What is the connection between the processes and technology of photography and its representation of modernist space? How can these relationships inform and articulate a photographic practice? This thesis comprises five key areas of investigation, with each theoretical chapter being followed by a complementary sequence of photographic images. The first section considers the process of `fragmentation' in relation to a body of photographs which I have termed `fragments'. These images reveal the aspirational or utopian content of modernist architecture as a condition of loss or melancholy. The second section develops the notion of the `fragment' in relation to `allegory', which I argue, opens photography to metaphoric interpretation thus taking on the duality of meaning. The third section uses W. G. Sebald's novel Austerlitz and Kracauer's work on history, to locate this duality within Husserl's Lebenswelt. The fourth section shifts the emphasis of inquiry towards an examination of how the utopian emerges within specific aspects of the photo-reprographic process, such as the error of misregistration in colour printing. This forms the basis for a development of the practice into the field of the photographic representation of colour. The fifth section looks at how colour has been added to the monochromatic image in a series of postcards of modernist architecture from the 1930's thus suggesting a site of utopian investment With reference to Kristeva and Benjamin I develop the notion of colour as an excess of meaning indicative of utopian aspiration. The conclusion of the project is firmly located in the practice outcome and a body of work, which I have termed `constructed images'. Representing a convergence of the five themes, these reveal the ability of photography to uniquely articulate the utopian-melancholy polarity, a transformative process, intervening into architectural space to indicate new ways of thinking about it.

The aim of the research that this thesis is based on is to explore the theoretical problems raised by the concept of photographic abstraction. These consist in the tension between the two aspects of the photographic sign, the indexical and iconic, and are examined in the context of the particular exploration of the empty space in abstract photography which I have pursued through my practice.

In the digital age, there has been a phenomenal rise in the number of photos people capture, share, and manipulate—a trend that shows no sign of slowing. Furthermore, research shows that photos—authentic and manipulated—are powerful; they can change people’s memories for distant and recent experiences, beliefs about past actions, intentions for future actions, and judgements. Yet there is currently limited research exploring the effects of digital photography on memory, cognition, and behaviour. Part One of this thesis comprises of a program of research that examines people’s ability to discriminate between authentic and manipulated images. Advances in digital technology mean that the creation of visually compelling photographic fakes is growing at an incredible speed. Despite the prevalence of manipulated photos in our everyday lives, there is a lack of research directly investigating the applied question of people’s ability to detect photo forgeries. The research in Chapter 3 addresses this question. Across two experiments, people showed an extremely limited ability to detect and locate manipulations of real-world scenes. Chapters 4 and 5 explore ways that might help people to detect image forgeries. Specifically, the research investigates the extent to which people can identify inconsistencies in shadows and reflections. The results suggest that people are reasonably insensitive to shadow and reflection information and indicate that such image properties might not help people to distinguish between authentic images and manipulated ones. Part Two of this thesis examines how the act of taking photos can affect people’s memory. Digital technology has revolutionised the ease with which people capture photos and accordingly there has been a remarkable rise in the number of photos that people take. The results of five experiments and a mini meta-analysis suggest that taking photos has only a small, or plausibly no, effect on people’s memories.

Assay technologies for GPCRs and their associated G-proteins are in demand for drug screening and other biotechnology applications such as biosensors for diagnostic purposes or odorant/flavour assessment as well as for elucidating the remaining controversial mechanisms in G-protein mediated signalling. This study aims to make progress towards developing a TR-FRET assay for G-protein interactions that could be used as a generic assay platform for GPCR signalling that would be fluorescent, homogeneous and amenable to miniaturization. The first chapter of this study investigates the use of small molecule labels, CS124-DTPA-EMCH:Tb and Alexa546 in a TR-FRET assay. This TR-FRET pair had previously been applied to Gα, Gβγ and RGS4 proteins and during the characterization of this assay, the protein CrV2 was observed to interact with the G-protein. Using TR-FRET, it was demonstrated that a high affinity interaction appears to occur between Gαi1 and CrV2 (Apparent Kd 6.2 nM). CrV2 is encoded by a polydnavirus from endoparasitoid wasps, which is thought to mediate immune suppression, and the interaction with Gα could have important implications in the regulation of the immune system of invertebrates. Improvements to the labelling strategy used in this assay are then attempted through the creation of various G-protein subunit fusions with small, genetically encoded lanthanide binding tags (LBTs) or tetracysteine motifs (TCMs) for site-specific labelling with terbium or FlAsH, respectively. The consequence of the fusions on maintaining G-protein subunit integrity and on the affinity of the tags for their labels is characterized, and then the utility of these constructs as TR-FRET partners is demonstrated. TCM:FlAsH complexes could successfully be used as TR-FRET acceptors for CS124-DTPA-EMCH:Tb labelled binding partners. The interaction between Gβγ2-TCM:FlAsH and Gα:Tb could be measured using TR-FRET and generated an apparent Kd of 3.6 nM. Likewise, LBT:Tb complexes could be used as TR-FRET donors to Alexa546 labelled binding partners which was demonstrated using the chimeric, promiscuous Gα subunit, LBT2:Tb-GαS25 and Gβγ:Alexa. Furthermore, the two site-specific labelling strategies can be used together in TR-FRET studies and an interaction between LBT2:Tb-Gα[subscript]S25 and Gβγ₂-TCM:FlAsH was shown to have an apparent Kd of 2.3 nM. The TRFRET assays were further validated using protease treatments and the addition of unlabelled binding partners reduced the TR-FRET signal. Finally, the feasibility of fusing lanthanide binding tags to GPCRs for alternate assay platforms or other applications was investigated. The β₂- adrenergic and M₂-muscarinic receptors were fused to LBTs and the integrity of the receptors determined using ligand binding and [[superscript]35 S]GTPγS signalling assays. Terbium binding to the LBT was then demonstrated. The utility of these constructs in alternative TR-FRET platforms with Gproteins was then explored. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1363937 / Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2009

This thesis examines the relationship between photography and sociology as offering complementary ways of understanding ourselves and the world we live in. Drawing from the work of Pierre Bourdieu and Raymond Williams, I examine the idea of a ‘field’ of photography within the field of cultural production more generally. The practises of documentary photography, photojournalism and fine art photography are explored with specific reference to images of war. In this arena, the politics, aesthetics and ethics of representing the body in pain are addressed.