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    Concurrent Viola Jones classifiers on a portable Beowulf cluster : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University
    (Massey University, 2008) Chemudugunta, Ravi Kiran
    Real-time Computer Vision is an interesting application for supercomputing, real-time applications (vision processing in particular) employ special purpose hardware such as DSPs to achieve high performance. This thesis explores parallel computers particularly commodity general purpose hardware. We also build a prototype to better understand the economics of supercomputing, specifically related to mobile computing - low power, rugged design by building a mobile computer. A new communication layer is built, where by the nature of the locality of the nodes allows one to optimise the protocols to reduce the latency comparably. Finally a study and in depth results of the algorithm, the Viola Jones Object detector in parallel are presented followed by reflection and future work based on the current results and platform.
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    The influence of mindfulness in attention based tasks : a thesis presented in partial fulfillment of the requirements for the degree of Master of Arts in Psychology at Massey University
    (Massey University, 2008) Marshall, Alana Brandy
    Mindfulness, defined as the self-regulation of attention so that it is maintained on immediate experience, has demonstrated clinical efficacy for the treatment of a diverse range of mental and physical health concerns. This study sought firstly, to determine whether the mindfulness attention awareness scale (MAAS) developed by Brown and Ryan (2003) in America would be applicable for use with an adult sample in New Zealand. Secondly, this study investigated whether mindfulness, as measured by the MAAS, could be linked to enhanced attentional processing using attentional paradigms from cognitive psychology, including inattentional blindness (IB) and change blindness (CB) tasks. The results support the use of the MAAS with adults in New Zealand. The results also show that participants in the high mindfulness group detected the unexpected event in the IB task and reported changes in the CB task significantly more often than participants in the low mindfulness group. This finding provides support for the prediction that mindfulness and the MAAS would be associated with improvements in sustained attention and switching, in addition to facilitating the identification of objects in unexpected contexts. The results suggest the use and development of mindfulness as a tool to enhance attentional processing for a variety of psychotherapy, occupational, and sporting processes. The discussion considers these issues along with some reservations regarding the use of the MAAS, limitations of the study, and suggestions for future research.
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    Disinhibition in human vision : being a thesis submitted as a partial requirement for the degree of Master of Science with Massey University
    (Massey University, 1981) Scheirlinck, Joanne Gemma Maria
    Recent electrophysiological and psychophysical data have suggested that within the human visual system there exists specialised neural units which respond maximally to specific orientations. This suggestion is based upon electrophysiological data recorded from orientation specific neurons in the cortex of the cat and monkey, and psychophysical studies of normal observers. Following a review of this literature three psychophysical paradigms (masking, aftereffect, and dichoptic aftereffect) were utilized to investigate disinhibition of orientation analyzers in humans. Chapter two examined the spatial selectivity of the disinhibition function with successive presentation of two masking gratings. The results indicated that, for a vertical test stimulus, disinhibition was maximal when the orientations of M1 and M2 were similar and was minimal when the orientational difference was greater than 15 deg. Chapter three investigated disinhibition in the orientation aftereffect, following both successive and simultaneous presentation of two adaptation gratings. The results showed that regardless of the temporal sequencing the addition of a second grating could either disinhibit or summate the magnitude of the aftereffect. Generally, interaction was maximal when when the orientation difference between the gratings was 15 deg. Dichoptic presentation of stimuli (chapter four) demonstrated that orientation disinhibition may be a high level effect at least parallel to that of binocular rivalry. The results indicated firstly that disinhibition and summation were maximal when the orientation difference between the gratings was 15 deg and secondly that these functions could not be disrupted by binocular rivalry. The results of this thesis are in keeping with a lateral inhibition explanation of orientation disinhibition. This lateral inhibition system is consistent with a general feature detection model of visual perception which is known to exist in humans.