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A LIDAR-compatible approach to remote sensing of water temperature using Raman spectroscopy
No full textEmpirical thesis.Bibliography: pages 193-203.Chapter 1. Introduction -- Chapter 2. Experimental and analysis methods -- Chapter 3. Raman spectroscopy as a technique for natural water temperature determination -- Chapter 4. LIDAR-compatible multichannel Raman spectrometer using green (532 nm) excitation light 97 -- Chapter 5. LIDAR-compatible multichannel Raman spectrometer using blue (473 nm) excitation light 132 -- Chapter 6. Conclusions and future outlook -- Bibliography -- Appendices.The measurement of water temperature provides essential information for the understanding of the water column dynamics, being important for research fields including oceanography, climate change, marine ecology, fisheries and coastal management. Traditional in situ measurements provide accurate depth-resolved information at limited spatial and temporal scales. As an alternative suitable for large scales studies, researchers may rely on remote sensing tools such as passive satellite sensors and active LIDAR (Light Detection and Ranging) methods. However, satellite-derived sea surface data are restricted to the first micrometres of the water column, not providing information regarding vertical structure and stratification. LIDAR methods employ active excitation and fast time-resolved detectors, allowing for depth-resolved measurements performed from airborne or ship-based platforms and, when coupled to spectroscopic measurements, have the potential to assess subsurface water temperature.The aim of this research work is to develop LIDAR-compatible spectroscopic methods for monitoring water temperature based on the inelastic Raman scattering of photons in water. Raman scattering in water exhibits a temperature-dependent behaviour, which can be used to estimate temperature markers for remote sensing predictions. The analysis of Raman spectra from natural water samples, which were acquired by using a commercial Raman spectrometer (532 nm excitation) indicated that the presence of other optical signals in natural waters, such as fluorescence, may compromise the accuracy of Raman temperature sensing. In order to circumvent this issue, I proposed methods for spectral correction which resulted in temperature determination with improved accuracy.I designed and assembled multichannel LIDAR-compatible Raman spectrometers integrated to excitation lasers having green and blue wavelengths. The design allowed for simultaneous collection of unpolarised and polarised Raman signals, enabling the calculation of four temperature markers carrying different types of temperature information.Each marker was analysed in terms of accuracy of temperature predictions, sensitivities and percentage errors associated with signal-to-noise ratios. A novel linear combination method was employed to use all four temperature markers and was effective in enabling enhanced temperature predictions.The relative merits of using green and blue excitation were considered in the context of laboratory studies and proposed field implementation. The work presented in this thesis represents a major step forward in the quest for a LIDAR-based optical system to measure subsurface water temperature with an accuracy of ±0.5°C and depth resolution of 0.5 m in near real-time.Mode of access: World wide web1 online resource (243 pages) graphs, table
Visual ecology of Australian flathead
No full textThesis by publication.Bibliography: pages 30-36.I. Acknowledgements -- II. Abstract -- III. Introduction -- IV. Methodology -- V. Results -- VI. Discussion -- VII. Conclusion -- VIII. References -- IX. Appendix I -- X. Appendix II.Despite our growing understanding of fish visual ecology, the visual systems of relatively few benthic marine species have been described in detail. Flatfish are one of the largest groups of benthic fish, and in the New South Wales (NSW) region of the East coast of Australia, the Platycephalidae (flatheads) are the predominant and most diverse flatfish family. Flatheads are also important economically, accounting for $2.1 million in NSW fisheries revenue annually. The aim of this study was to investigate the anatomy and spectral sensitivity of the eyes of flatheads to identify correlations with habitat and behaviour, using one or more of the species found in NSW waters. Microspectrophotometry (MSP) was used to measure the spectral absorbance properties of the visual pigments in the rod and cone photoreceptors of the dusky flathead (Platycephalus fuscus) and blue-spotted flathead (Platycephalus caeruleopuntatus). The MSP data show that P. fuscus, which predominantly occupies shallow estuarine habitats, possesses multiple cone visual pigments with peak sensitivities in the short ('blue') to medium ('green') wavelength range of the spectrum. MSP data of P. caeruleopuntatus, which predominantly occupy deeper water marine habitats, shows that they possess similar multiple cone visual pigments to P. fuscus, but with a noticeable shorter wavelength shift in the single cone visual pigment. Spectrophotometry of the ocular media of both species reveals that the spectral absorbance of the lens limits the transmission of short wavelength light to the retina and effectively blocks wavelengths below about 400 nm. The topographic distribution of retinal neurons was also measured to establish the areas of the visual field sampled with high resolution. P. fuscus and P. caeruleopuntatus display a similar distributional topography with an elongated area present in the dorsal retina. The results of this study are compared with findings for other benthic fish species.Mode of access: World wide web1 online resource (38 pages) colour illustration
What's in a name?: Nomina Sacra and social semiosis in early Christian textual practice
No full textTheoretical thesis.Bibliography: pages 249-282Part One: Nomina Sacra in early Christian literature -- 1 Viewing Words and Reading Images -- 2 Sacred Signs in Human Script(ure)s --3 Signed with an "X" -- Part Two: Nomina Sacra in "everyday writing" -- 4 "Greetings in the L(or)d" -- 5 "For I Could Not Identify the Syllables" -- 6 "Not by Incantations, but by the Name of Jesus" -- ConclusionThe practice of abbreviating and supralineating certain sacred words, known as nomina sacra, is a remarkably widespread phenomenon across the spectrum of early Christian textual practice, appearing in materials from sacred literature to personal letters and learning exercises. While this practice has received considerable attention in the last century, approaches have generally been deductive and descriptive, and furthermore have largely been isolated to single genres of source material, with particular emphasis on their presence in literary manuscripts. Drawing on theories of social semiotics and multimodality, the present study takes an inductive and interpretive approach by analyzing particular instantiations of this practice across the broad range of materials in which it is employed. The study is divided into two parts. Part One examines the nomina sacra in early Christian literary culture. The nomina sacra are first positioned as visually and socially oriented signifiers of communal identity and expression; attention is then turned to their use in three particular Christian literary manuscripts; and finally, an answer is explored in regard to questions raised by the sacral treatment of "cross" and "crucify"and the use of the staurogram. Part Two presents case studies to address the use of nomina sacra in the "everyday writing" of early Christians-that is, in their letters,learning exercises, and amulets. Throughout the study, it is argued that the nomina sacra are best understood not as static signifiers with a standard set of forms and meanings, but as traces of dynamic and creative lived material practices by social/semiotic agents.1 online resource ( 282 pages
Parenting factors associated with children’s school-related anxiety: a preliminary study of parental overprotection and family accommodation
No full textThesis by publication.Bibliography: pages 66-76.1. Review paper - Parenting factors associated with childhood anxiety : a narrative review of parental overprotection and family accommodation -- 2. Empirical paper – Parenting factors associated with children’s school-related anxiety : a preliminary study of parental overprotection and family -- References -- Appendices.Childhood anxiety disorders are associated with significant distress and functional impairment that can lead to subsequent psychopathology persisting across the lifespan. Parental overprotection has been consistently implicated in the development and maintenance of childhood anxiety disorders. Similarly, family accommodation of anxious and avoidant child behaviours is linked with increased anxiety symptoms, lower functioning and poorer treatment outcomes in children with anxiety disorders. To date, the literature has largely focused on the relationship between parenting factors and associated child internalising distress and impairment within clinical populations, with minimal attention being given to pre-morbid or non-clinical samples experiencing heightened anxiety symptoms. This study examines the relationship between an overprotective parenting style and accommodating parental behaviours with children’s anxiety to stressors typically occurring within Australian primary schools. A sample of 52 male primary-school students between 8 and 11 years of age, and their parents were recruited from an independent primary school in a major Australian city. Self-report measures of parental overprotection and accommodation of children’s anxiety-related behaviours were analysed as predictors of children’s anxiety symptoms in relation to typical school-related stressors. Consistent with previous research within clinical populations, these results provide support for a moderate association between family accommodation and child anxiety related distress, although this relationship was not found when controlling for children’s trait anxiety. Parental overprotection was not found to be related to children’s anxiety symptoms in this study. Results are discussed with respect to models of child anxiety and empirical evidence regarding the roles of both child and parent factors in the development and maintenance of child anxiety. The limitations of the current study are reviewed and directions for further research are suggested.Mode of access: World wide web1 online resource (93 pages) diagrams, table
'I don't like it': A comparative analysis of emotions in the political rhetoric of Pauline Hanson from 1996-1998 and 2016-2018
No full textTheoretical thesis.Bibliography: pages 53-61Introduction -- Chapter 1: Out of the fish and chip shop and into Parliament: A literature review -- Chapter 2: Methodology and Preliminary Results -- Chapter 3: 1996-1998: Establishing a Regime -- Chapter 4: 2016-2018: Expanding a Regime -- Chapter 5 : Discussion and Conclusions -- Appendix -- References.In Australian politics and popular culture, few politicians have ever been considered as controversial as Pauline Hanson. From 60 Minutes to Pauline Pantsdown, from The House of Representatives to Dancing With the Stars and The Celebrity Apprentice, Hanson has barely left the public imagination since her explosive entrance into politics in the 1996 federal election. Hanson's successful 2016 election to the Senate has once again brought her firmly into the spotlight and raised questions of how Hanson succeeded a second time. While Hanson has been discredited on both the political left and right as the 'ignorant' and 'racist' voice of a minority, our most outcast members of the Government can show us surprising cultural truths. This thesis explores how Pauline Hanson's political discourse has changed over the last 18 years and the role that emotions play in her speeches. Through a content and an applied thematic analysis of Hanson's Parliamentary speeches from 1996-1998 and 2016-2018, this thesis will highlight the mirroring of emotional regimes of the radical populist right in the Australian political sphere.1 online resource (61 pages) illustration
Morphisms of 2-dimensional structures with applications
No full textEmpirical thesis."Centre of Australian Category Theory (CoACT), Department of Mathematics" -- title page.Bibliography: pages 103-106.1. Introduction and overview -- 2. Strictification tensor product of 2-categories -- 3. Cauchy completeness and causal spaces -- 4. Comonadic base change -- 5. Conclusion and outlook -- Appendices.This thesis consists of three chapters providing solutions to three problems. All of them involve morphisms of bicategories: lax functors, enriched categories, and categories enriched on two sides.The first problem was to obtain explicit constructions for various 2-categories which represent 2-categorical concepts involving monads and comonads. We considered lax functors (these are the morphisms of bicategories in the sense of Bénabou) between 2-categories C and D and define strictification tensor product for them. Let Lax (C,D) denote the 2-category of lax functors, lax natural transformations and modifications, and [C,D]lnt its full sub-2-category of (strict) 2-functors. Since monads can be seen as lax functors from 1 (the terminal category), the bicategory of monads in D, denoted Mnd(D), is isomorphic to Lax(1,D). A concise way of defining distributive laws is as monads in Mnd(D).The second problem involves enriching in a monoidal category similar to the one used by Lawvere to obtain (generalized) metric spaces. He expressed Cauchy completeness in purely categorical terms which led to the possibility of applying it to an arbitrary base; for example, an ordinary category is Cauchy complete when all its idempotents split. What we do is to obtain spaces of relativistic events as enriched categories and show that they are always Cauchy complete in the categorical sense. We then see this as a more general phenomenon by providing conditions on the base monoidal category which ensure Cauchy completeness of those enriched categories having all idempotents splitting in the underlying category. The splitting condition was not seen in the case of our partially ordered base since the only idempotents are identities.Finally, in order to analyse Cauchy modules for categories enriched in graded and differential graded Abelian groups (GAb and DGAb), we consider two-sided enriched categories between bicategories, forming a tricategory Caten. The construction of DGAb from Ab, which exists in the literature, can be factored via GAb, and we prove that it is an instance of semidirect product of Hopf bimonoids, applicable to an arbitrary base symmetric monoidal category. To extend this approach to the bicategories of modules, we considered a generalization from Hopf bimonoids in a symmetric monoidal category to Hopf comonads in Caten. The crucial property of such comonads is that the forgetful functor creates left Kan extensions,which generalizes creation of duals and cohoms in the monoidal category case, and adjoints in the bicategory case.Mode of access: World wide web1 online resource (xiv, 106 pages) diagram
Characterisation of music, photo and object evoked autobiographical memories in healthy elderly people
No full textEmpirical thesis."Department of Psychology & Australian Research Council Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, Australia" -- title page.Bibliography: pages 46-49.Introduction -- AM triggers -- The current study -- Method -- Results -- Discussion -- Conclusion -- References -- Tables -- Appendices.Recent literature suggests that autobiographical memories can be evoked involuntarily, and in detail, with the use of music and objects – producing evidence across groups of healthy adults and even clinical groups with memory impairments. However, neither music nor objects have been compared with other stimuli amongst healthy elderly people. This thesis compares the incidence of music-evoked autobiographical memories (MEAMs), photo-evoked autobiographical memories (PEAMs) and object-evoked autobiographical memories (OEAMs). Twelve participants (six male and six female) reported memories following exposure to: (1) 16 famous songs across 1930-2010 (rated number one in Australian music charts for the longest duration); (2) 17 photos (of famous events), two from each decade 1930-2010; and (3) 16 iconic household objects, two from each decade 1930-2010. Memories were reported via oral questionnaires. Statistical analyses revealed that there was a significantly lower proportion of MEAMs relative to PEAMs and OEAMs, with the number of PEAMs and OEAMs being statistically similar. There was no significant correlation between the frequency of MEAMs or OEAMs and familiarity ratings, but there was a significant positive correlation between PEAMs and familiarity ratings. There was a clearly defined reminiscence bump for MEAMs, but an extended reminiscence bump for PEAMs/OEAMs. This investigation is the first to characterise and compare autobiographical memories evoked by music, photos and objects amongst a healthy elderly population group. Results are discussed in view of research on age-related memory decline, and the potential to re-activate memories using carefully selected triggers.Mode of access: World wide web1 online resource (55 pages) graphs, table
Decision-making and action selection in honeybees: a theoretical and experimental study
No full textEmpirical thesis.Bibliography: pages 177-214.1. Introduction -- 2. Literature review -- 3. The role of inhibition in decision making -- 4. Is honeybee decision-making described by a drift-diffusion process? -- 5. A computational model of decision-making -- 6. Future work and conclusions -- Appendices.Decision-making is an integral part of everyday life for animals of all species. Some decisions are rapid and based on sensory input alone, others rely on factors such as context and internal motivation. The possibilities for the experimental investigation of choice behaviour in mammals, especially in humans, are seemingly endless. However, neuroscience has struggled to define the neural circuitry behind decision-making processes due to the complex structure of the mammalian brain.For this work we turn to the honeybee for inspiration. With a brain composed of approximately 10 to the power of 6 neurons and sized at a tiny 1mm to the power of 3, it may be assumed that such an insect produces mere `programmed' behaviours, yet, the honeybee exhibits a rich, elaborate behavioural repertoire and a large capacity for learning in a variety of different paradigms. Indeed, the honeybee has been identified as a powerful model for decision-making.Sequential sampling models, originating in psychology, have been used to explain rapid decision-making behaviours. Such models assume that noisy sensory evidence is integrated over time until a threshold is reached, whereby a decision is made. These models have proven popular because they are able to fit biological data and are furthermore supported by neural evidence. Additionally, they explain the speed-accuracy trade-off, a behavioural phenomenon also demonstrated in bees.For this work we examine honeybee choice behaviour in different levels of satiation, and show that hungry bees are faster and less accurate than partially satiated bees in a simple choice task. We suggest that differences in choice behaviour may be attributed to a simple mechanism which alters the level of the decision threshold according to how satiated the bee is. We further speculate that the honeybee olfactory system may be a drift-diffusion channel, and develop a simple computational model, based on honeybee neurobiology ,with simulations that match behavioural results.Mode of access: World wide web1 online resource (214 pages) diagrams, graphs, table
Understanding SME employees' security behaviours when performing work tasks using BYOD from multiple work locations
No full textTheoretical thesis.Bibliography: pages 68-85.1. Introduction -- 2. Review of the literature -- 3.Theoretical framework -- 4. Research design and methodology -- 5. Data analysis and results -- 6. Discussion -- 7. Conclusion -- Appendices.The focus of this study is to examine the security behaviours of SME employees who unintentionally misuse information systems or do not comply with security policies when working from multiple locations using BYOD. SMEs underestimate the security risk their employees may encounter when working from locations other than a central office location. SMEs have resource constraints (human and financial capital) that preclude them from focusing on protecting information assets. At the same time, SMEs attract talent by offering flexible work arrangements such as working from home, a co-working centre or other locations other than the office (anywhere working). This study investigated factors that explain SME employees’ security behaviour. The constructs for the theoretical model were developed from protection motivation theory, the theory of planned behaviour, habit, hardiness and stress. The constructs were empirically validated using data collected from 294 SME employees. The results of the study show that hardiness, stress and habit have a significant impact on employee’s security intentions when working from multiple locations using BYOD. The study contributes to information security study by highlighting the importance of an employee’s hardiness personality trait in framing their positive security behaviour.1 online resource (xi, 95 pages : illustrations
Age and professional identity: EFL teachers at tertiary institutions in Japan
No full textTheoretical thesis.Bibliography: pages 76-85.1. Age in academia -- 2. Literature review -- 3. Methodology -- 4. Findings : life histories -- 5. Findings : themes -- 6. Discussion -- 7. Conclusion -- Appendices -- References.This qualitative study, which uses a narrative inquiry approach, presents data from in-depth interviews with seven participants working in EFL at tertiary institutions throughout Japan. This thesis contributes to the field of language teacher identity by expanding it to include a focus on the construct of age as a key component of identity. It was found that the participants’ age identities were co-constructive of their professional development; that they constructed their age contextually, relative to the ages of their students and other teachers; the participants’ age identities were chronologically framed by their institutions and used to manage their professional opportunities.1 online resource (85 pages) diagrams, table