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Using quality of family life factors to explore parents’ experience of educational provision for children with developmental disabilities in rural Australia
No full textAustralian education service provision includes the delivery of quality educational programmes to rural and remote living children. However, according to their parents, many children with developmental disabilities (such as Down Syndrome and Autism Spectrum Disorders) who are living in rural country areas in New South Wales (NSW) still do not have access to an acceptable education programme. This study aimed to use quality of life factors via a family quality of life scale to explore 51 parents’ experience of educational service provision for their children with developmental disabilities in rural NSW. The results indicated that successful engagement with the school system is strongly affected by the views, assumptions, expertise and prejudices of teaching and care professionals. Further research into how local educational service providers may assist rural Australian families with a child with IDD in rural and remote locations is warranted.17 page(s
One size does not fit all : monitoring faecal glucocorticoid metabolites in marsupials
No full textMarsupial research, conservation, and management can benefit greatly from knowledge about glucocorticoid (GC) secretion patterns because GCs influence numerous aspects of physiology and play a crucial role in regulating an animal's response to stressors. Faecal glucocorticoid metabolites (FGM) offer a non-invasive tool for tracking changes in GCs over time. To date, there are relatively few validated assays for marsupials compared with other taxa, and those that have been published generally test only one assay. However, different assays can yield very different signals of adrenal activity. The goal of this study was to compare the performance of five different enzyme immunoassays (EIAs) for monitoring adrenocortical activity via FGM in 13 marsupial species. We monitored FGM response to two types of events: biological stressors (e.g., transport, novel environment) and pharmacological stimulation (ACTH injection). For each individual animal and assay, FGM peaks were identified using the iterative baseline approach. Performance of the EIAs for each species was evaluated by determining (1) the percent of individuals with a detectable peak 0.125–4.5 days post-event, and (2) the biological sensitivity of the assay as measured by strength of the post-event response relative to baseline variability (Z-score). Assays were defined as successful if they detected a peak in at least 50% of the individuals and the mean species response had a Z⩾2. By this criterion, at least one assay was successful in 10 of the 13 species, but the best-performing assay varied among species, even those species that were closely related. Furthermore, the ability to confidently assess assay performance was influenced by the experimental protocols used. We discuss the implications of our findings for biological validation studies.11 page(s
Three essays on investor confidence: a new measure, empirical application and experimental evidence
No full textTheoretical thesis."A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in a cotutelle agreement between CMMU, College of Management, Mahidol University, Bangkok, Thailand; Faculty of Business and Economics, Macquarie University, Sydney, Australia" -- title page.Bibliography: pages 141-152.1 Introduction -- 2 Aggregate invesor confidence in the stock market -- 3 Aggregate investor confidence, price momentum and asset pricing -- 4 Investor overconfidence in experimental asset markets across market states -- 5 Conclusion.This PhD research is committed to contributing to the literature on investor overconfidence, one of the most robust findings in the field of behavioural finance. Overconfidence, a cognitive bias where decision makers tend to be overly optimistic not only about their aptitudes and skills, but also about the precision of their forecasts and information, is associated with poor decision making. Individuals suffering from overconfidence tend to be excessive stock traders, Chief Executive Officers (CEOs) who rush into mergers and acquisitions, risky drivers, naïve entrepreneurs and sloppy retirement planners. The literature yields the many attempts to link stock market phenomena to overconfidence. However, existing measures that have been used to test these hypotheses are typically only loosely related to the overconfidence of investors in their own abilities, or use proxies that lack a formal model of cognitive psychology. In the first of three research projects, I propose a measure of aggregate investor confidence that is based on a cross-disciplinary model containing determinants of confidence. The measure captures major economic events intuitively, and is statistically distinct from exiting proxies. Using a 1926-2011United States (US) sample, I find that the new measure is a better predictor of aggregate trading activity than past stock returns, which have been used in prior studies.The second research project explores the role of aggregate investor confidence in asset pricing factors. Empirical tests reveal interesting patterns. Firstly, and in line with a behavioural model by Daniel, Hirshleifer, and Subrahmanyam (1998), aggregate investor confidence partially explains variations in the profitability of momentum strategies. Additionally, aggregate investor confidence appears to play a key role in the size factor, complementing an early hypothesis by Roll (1981). Indeed, investors seem to systematically change their risk perceptions which ultimately impacts on market outcome. The third research project takes a qualitative stance. Using a new methodology proposed by Glaser, Langer, and Weber (2013), we utilise the ability to assess time series variations of individual overconfidence levels in an experimental asset market. We find that arriving signals that strongly support prior decisions cause overconfidence to prevail, while strongly opposing signals cause the effect to vanish 'overconfidence crashes'. However, previously lost overconfidence can re-emerge when these opposing signals reverse .Additionally, we find strong evidence in favour of the hypothesis by Hongaund Stein (2007) which states that investors interpret arriving information differently with opposing feedback having particularly strong effects. We also find measurement bias in the methodology proposed by Glaser et al. (2013). This is consistent with methodological concerns documented by Langnickeland Zeisberger (2016) and Biais, Hilton, Mazurier, and Pouget (2005) who report that assessment tasks using confidence intervals typically yield inflated overconfidence scores, as individuals tend to be insensitive to confidence levels in their estimations.Mode of access: World wide web1 online resource (viii, 152 pages) graphs, table
An extension of model selection curves framework to accelerated failure time models
No full textEmpirical thesis.Bibliography: pages 147-154.1. Introduction -- 2. Accelerated failure time models for survival analysis -- 3. Model selection framework -- 4. Simulation study -- 5. A tool in R for AFT model selection -- 6. A case study using the model selection framework -- 7. Conclusion -- Appendices -- Bibliography.In most existing model selection criteria, a constant penalty multiplier is usually paired with a penalty function. A model selection criterion based on a single value of penalty multiplier, such as Akaike information criterion (AIC) and Bayesian information criterion (BIC), can be "unstable" as a different model may be selected if the penalty multiplier changes even by a small arbitrary amount. This thesis extends a recently developed model selection approach for (generalised) linear models, known as model selection curves (MSC), to accelerated failure time (AFT) models for survival data. In this approach, penalty multiplier in a predetermined range, instead of a single value, is considered. Model selection criteria based on this approach are thus considered more stable as the selected model is the least likely not to be selected even when the penalty multiplier changes. In addition to the two recently introduced longest cathetus criterion and longest hypotenuse criterion, a new criterion, called the triangle area criterion, is proposed in this thesis. Under some conditions, these three criteria are consistent in selecting a specified AFT model, similar to BIC. It is shown that the consistency result seems to hold even when sample size is only reasonably large using simulations. A model selection framework including these three MSC based criteria, as well as BIC and AIC, is proposed for AFT models of survival data.The framework was investigated through simulations considering survival data of various sizes and censoring proportions from different specified models. Moreover, the performance of those model selection criteria based on the MSC was examined in comparison to AIC and BIC. The results indicate that those criteria have the potential to outperform AIC and BIC in selecting the correct model. The model selection framework has also been applied to several real world survival data. A tool in R program is developed to visualise the results from applying the framework.Mode of access: World wide web1 online resource (xviii, 154 pages) graphs, table
Experimental implementations of multidimensional multi-photon states
No full textEmpirical thesis.Bibliography: pages 137-145.1. Introduction -- 2. Spontaneous parametric down conversion -- 3. Experimental setup -- 4. Spatial entanglement detection using raster scan with a phase-slit -- 5. Direct detection of the moments of spatial probability distribution -- 6. Spatial entanglement: towards 4-photon momentum entangled states -- 7. Conclusion -- References.Multi-particle entangled states are becoming more and more interesting for different applications in quantum information, such as quantum multi-particle teleportation, entangled based cryptography and quantum communication schemes based on multi-particle states, but also for fundamental reasons such as testing local realism by means of the Greenberger-Horne-Zeilinger states (GHZ) arguments . The advantage of multiparticle entanglement versus the most common two particle one lies in the fact that the greater the number of particles involved in the entangled state, the more clearly the quantum effects are exhibited. Our final goal is to exploit the multi-photon entangled states for quantum metrology. By the interaction of those states with nanostructures (mostly nanoholes, but in a future also nanospheres), we expect to reach sub-wavelength sensitivity phase measurements beating the Standard Quantum Limit as well as to detect plasmonic effects.In this thesis we present our work consisting on designing and building an experimental setup for the generation of states of 4-photon entangled in the transverse linear momentum. In the first part we explain some basics in the form of a technical introduction. We then adapt a general theoretical model to our particular case, explaining the physics of the process of generation of entangled states of photons. We proceed explaining the details of our setup, as well as the procedure of measurement. We then present the results of our tests in a "standard" 2-photon regime to show the correct functioning of the setup itself. Some more sophisticated measurements using structured light in the form of a first-order Hermite-Gaussian mode has been performed to generate entanglement in higher spatial modes are also presented. We conclude with theoretical and experimental details regarding the 4-photon experiments feasible with our setup.Our source is based on Spontaneous Parametric Down-Conversion (SPDC). In the last two decades it has been extensively studied for the generation of two-photon entangled states, since Kwiat et al. published in 1995 the new scheme based on polarization entangled photons. Most of the studies regarding entangled states involving more than two photons are indeed based on quantum correlations in the polarization or in the path of the down converted beams. The great advantage of entangling a spatial degree of freedom (as we do) is related to the dimensionality of the Hilbert space in which the state is defined. In the particular case of linear momentum, which is a continuous variable, we are dealing with infinite dimensions. Since in each dimension of the state one quanta of information can be encoded, the advantage of having multidimension entanglement for the field of quantum communication and computing is clear.The specs of our setup include a periodically-poled KTP crystals offering high conversion efficiency and cut for type-0 SPDC. The photons generated are well known to be inherently entangled in different degrees of freedom such as polarization, energy-time, linear momentum, and orbital angular momentum. Since each single SPDC event generates one photon pair, in order to reach four photon we entangle two consecutive SPDC events per each state. Furthermore, it is possible to manipulate (to enhance) the dimensionality of the entanglement by properly tailoring the pump spatial profile.The key point for the generation of four-photon entangled states is that, under some conditions, two consecutive pairs generated via SPDC cannot be described as two independent pairs but necessarily as a four-photon state showing genuine entanglement. This can happen when using a pulsed laser to generate the entangled photons; in particular, in the regime in which the coherence time of the down-converted photons τc is (much) longer than the temporal length of the pumping pulse Δt. In this condition the emission of a second pair is stimulated by the presence of the first one. That effect can be ultimately seen as a constructive multi-particle interference effect, the deep origin of which has to be sought in the boson statistic of photons.Mode of access: World wide web1 online resource (xviii, 145 pages) colour illustration
Transmission-line modelling of microstrip antennas and their application in fixed-frequency beam steering
No full textEmpirical thesis.Bibliography: pages 181-199.1 Introduction -- 2 Reconfigurable antennas: Background -- 3 Rectangular microstrip antennas: A transmission-line approach -- 4 Arbitrary position of a shorting post: Modelling and effects -- 5 Active rectangular microstrip antenna: Limitations of the model -- 6 Active antenna beam steering: Voltage controlled scanning - 7 New reconfigurable meta-surfaces: Transmission-line modelling -- 8 Periodic 3D array of square plates: EM energy transport -- 9 Fixed-frequency broadside-endfire scanning: A new antenna -- Conclusions and future work.Planar antennas are paramount in today's world because they can be embedded easily into portable devices such as laptops, mobile phones, etc. Beam or the radiation with directivity is important beacause it gives a suitable range advantage than omnidirectionally radiating antennas with the same power. Steerability can provide the flexibility of the omnidirectional antenna and the benefit of a directional antenna; provided that multiplexing is possible. Reconfigurable antennas that can radiate multiple patterns at a single frequency or a single spectrum are necessary for modern telecommunication systems. The requirements for increased functionalities like direction finding, beam steering, radar, control and command, within a confined volume place a greater burden on today's transmitting and receiving systems. Reconfigurable antennas offer an exceptional solution to this complex engineering problem.This thesis contains the design of two particular fixed frequency beam-steerable antennas. The antennas are cost effective from the industrial perspective, and reliable for long term maintenance free use. The first one is a fixed frequency active phased array antenna. The relevant chapter showcases the layouts and results for two 1 x 2 variants and one 2 x 2 variant. Initial development of accurate transmission line models gave the insight of developing a fixed frequency active phased array antenna. Initial chapters outline the transmission-line modelling of single tunable and reconfigurable rectangular microstrip antenna elements. Analytically obtained values reasonably agree with the results achieved from measurements and simultaions, for numerous designs based on multiple substrates. The active phased array antenna can steer its beam up to 25°.The limitations of the phased array antennas led to the design of the second fixed frequency beam-steerable antenna. The second beanm-steerable relies on a switchable ground plane that can reflect or transmit electromagnetic waves. The second antenna has a steerable beam that radiates either in the broadside or endfire region. The antenna can cove up to 133° in the H-plane. Later chapters in this thesis discuss the transmission-line modelling of the reconfigurable surface with numerous examples, and its operation as a surface waveguide. The examples for the transmission-line model demonstrate reasonable agreement with simulation results for different substrate thickness and with or without a dielectric cover.The thesis presents a comprehensive overview of simulation and measurement results for multiple antenna designs backed by a reliable transmission-line model insight. Substantial area coverage is possible with the proposed antennas. Behavioural modelling software can benefit from the models discussed to create quick design solutions without wasting time for full-wave numerical calculations.Mode of access: World wide web1 online resource (xxxii, 199 pages) illustrations (some colour
English language teachers’ perceptions and the impact of a standardised professional development program in Sabah, Malaysia: a mixed methods study
No full textTheoretical thesis.Bibliography: pages 365-375.Chapter 1. Introduction -- Chapter 2. Literature review -- Chapter 3. Research methodology -- Chapter 4. What teachers want in a professional development program -- Chapter 5. Teachers' perceptions of the proELT -- Chapter 6. Teachers' experiences with the proELT -- Chapter 7. The proELT coursebook -- Chapter 8. Discussion -- Chapter 9. Conclusion -- References -- Appendices.Professional development of language teachers can be of enormous benefit if conducted in an effective way, but can sometimes result in unsatisfactory outcomes and sub-optimal use of resources. This study investigates EFL teachers’ perceptions and the impact of the ProELT (Professional Up-skilling of English Language Teachers) which was a nationwide, one-year program designed and conducted by the British Council Malaysia. A review of previous studies revealed a paucity of research focusing on large scale, standardised teacher professional development programs that involved participation of EFL teachers from both heterogeneous teaching levels (i.e. primary and secondary schools) and heterogeneous districts (i.e. urban and rural). The limited published studies available have been critical of this mode of professional development for a number of reasons, and the purpose of this study was to investigate these issues in the Malaysian context. A mixed methods explanatory sequential design was adopted, which utilised a questionnaire survey, interviews and focus groups with the teachers and District English Language Officers (DELOs), and a coursebook content analysis.Four major weaknesses of the ProELT were identified. First, the selection method of the program participants was ineffective because it did not align with the program objectives. The selection was based solely on a measure of the participants’ language proficiency, but no attempt was made to assess the teachers’ instructional competency. It resulted in the experienced teachers feeling dissatisfied that their teaching experiences were disregarded and some of them were negatively and emotionally affected. In addition, the standardised program coursebook was mostly irrelevant to the teachers’ curriculum specifications, with the outcome that the majority of the teachers interviewed failed to implement the program resources in their lessons. Finally, there was no follow-up from the program trainers in the form of classroom observations and visits, and meetings, amongst others, at the end of the program. Participants also reported a lack of support and communication from the Malaysian Ministry of Education who was the program provider.The findings of the study further problematise the application of standardised or “one-size-fits-all” professional development programs in the EFL context in the developing world such as Malaysia which places high emphasis on enhancing teachers’ and students’ English proficiency by allocating RM135 million (AUD44 million) for English language enhancement programs, and have theoretical and practical implications for PD on a broader scale.Mode of access: World wide web1 online resource (xxii, 425 pages) colour illustration
Ultra-low power FFT processor design for IoT devices
No full textEmpirical thesis.Bibliography: pages 44-45.Chapter 1. Introduction -- Chapter 2. The characteristics of IEEE 802.11ah WiFi standard and its requirements for an FFT processor -- Chapter 3. Fast Fourier Transform : the algorithms and architecture that define it -- Chapter 4. MATLAB and VHDL implementation -- Chapter 5. Verification and evaluation -- Conclusions and future work -- Abbreviations -- Appendices -- Bibliography.In a world where sensor data can be collected through smart grid and sensor backup applications, reducing power consumption has become one of the most important factors for data transmission. FFT processing is capable of low power, high throughput sensor data collecting. The IEEE 802.11ah standard is designed with the physical layer (PHY) and the medium access control (MAC). This paper discusses developing an FFT processor for this new standard. A simulation of the FFT processor is created in MATLAB, along with a VHDL component that handles the FFT architecture. These two are then tested for competency and validity, before then testing each other for evaluation and results.Mode of access: World wide web.1 online resource (xv, 45 pages diagrams, graphs, tables
Air flow and heat transfer study in a computer for domestic use
No full textEmpirical thesis.Bibliography: pages 68-71.Chapter 1. Introduction -- Chapter 2.Literature review -- Chapter 3. Methodology -- Chapter 4. Meshing and convergence tests -- Chapter 5. Simulation results and discussion -- Chapter 6. Thesis solution -- Chapter 7. Conclusions and future work -- Abbreviations -- References -- Appendix.The influence of computers on several aspects of our lives has been increasing continuously since the last decade. More attention to their safety and persistent operation is deemed necessary and has become an important matter. Personal computers (PCs) play a major role in industrial and domestic applications due to their wide applications. One of the major concerns faced by PCs s is their overheating issue. Overheated PCs might lead to several operational errors and safety problems, and might also lead to the loss of important data which is unable to be recovered in some circumstances. Cooling systems which typically consist of inlet air and exhaust fan play a vital role in removing heat from the main sources of heat generation, such as the motherboard within the PC. This study examines the mechanisms of the cooling process in typical PCs used in the market using a computational fluid dynamics (CFD) approach. A number of models have been created using AutoCAD and exported to an ANSYS package, where the fluid flow and thermal performance are investigated. The most realistic models have been identified and subsequent simulation results are conducted and discussed based on these models. Parametric studies by varying flow rates the magnitude of heat fluxes are performed in order to study the thermal characteristics within the PCs under different scenarios. Temperature distribution, which is the main focus in this work, is studied extensively at different air flow rates. Fan modelling is included in this study as the key recommendation to the investigated models. Optimum configuration of fan speed and heat flux is identified and proposed in this thesis.Mode of access: World wide web.1 online resource (73 pages illustrations (some colour)
A multi-valenced investigation of customer engagement within a social service
No full textThesis by publication.Bibliography: pages 328-345.Chapter One. Research objectives, contributions and context -- Chapter Two. Theoretical foundations for the study of customer engagement -- Chapter Three. Qualitative investigation and analysis -- Chapter Four. Guiding the inquiry -- Chapter Five. Analysis of the structural model and research hypotheses -- Chapter Six. Integrated conclusions, contributions and implications -- Appendices -- Bibliography.The literature on customer engagement continues to favour its positive valence, leaving limited research on the negative valences of consumer engagement and the detrimental impact they have on service relationships. This thesis explores positive engagement, disengagement and negative engagement to provide a more encompassing perspective of customers' service experiences. This thesis is the first study to explore three valences of engagement concurrently within a social service relationship, and uncover their affective, gognitive and behavioural dimensions. In addition, consumer engagement (CE) has seldom been applied in a social service context, despite the importance and centrality of social services to customers' lives. This thesis therefore explores positive, negative and disengaged valences of CE within a social service, being Australian local governments. Further, the literature has rarely considered how consumers engage with other touch points or objects, outside their direct interactions with a brand.As such, this thesis explores multiple valences of CE in relation to dual engagement objects, being a focal service organisation, and a service community. In order the examine the degrees to which CE is generalisable or contextually contingent, the thesis tests an empirical model of positive and negative CE across two contrasting service sectors: Australian local governments and social networking sites.The qualitative phase employed four focus groups and one in-depth interview to uncover the nature and characteristics of each engagement valence. Disengagement was characterised by passive, yet negatively-valenced responses of distrust, frustration, rejection and neglect. Negative engagement was more active and persistent, and involved anger, confrontive coping and collective complaining. Positive engagement was highly social, and manifested through trust, altruism and autonomous co-creation. Interestingly, consumer disengagement and negative CE were directed exclusively at the 'service organisation' object, being respondents' local governing body, whereas positive CE manifested exclusively towards their 'community' object, being the local community.The second, quantitative phase comprised of an empirical survey (n=625) administered to customers of Australian Local Government areas, and, users of the Social Networking Sites (Facebook, LinkedIn and Twitter). Structural Equation Modelling using AMOS 24 was employed. The results revealed involvement to be a strong antecedent of positive CE, and, positive CE to be a strong driver of WOM. These relationships were consistent across the dual objects and service types, suggesting the process of positive CE is generalisable across different foci and service contexts. Conversely, involvement had a moderately negative impact on negative CE, whereas negative CE acted as a positive driver of WOM. These relationships were revealed to have context specificity, as the negative impact of involvement on negative CE was stronger within the social service compared to Social Networking Sites. Further, negative CE was a stronger driver of WOM for the 'organisation' object in the social service. This suggests that negative feelings such as hatred and contempt, and anti-brand behaviours such as boycotting and blogging may be more relevant indicators of negative CE in local governments compared to social media platforms.The findings of this thesis provide several new insights into the nature of CE. Firstly, it clarifies how engagement can manifest through multiple valences by exploring customer disengagement and negative CE in conjunction with positive engagement. This illustrates that engagement is not exclusively positive, but, can adopt a range of valences that have both positive and negative impacts on service relationships. Secondly, this study elucidates the dynamic nature of engagement by exploring how it manifests towards two key aspects of a service relationship. Lastly, this thesis uncovers the contextual generalisability of CE by firstly, applying it within a new and unique social service setting, and secondly, testing its operation across two contrasting service types.Mode of access: World wide web1 online resource (xv, 345 pages) table