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Error entropy model based determination of minimum detactable deformation magnitude of terrestrial laser scanning
No full textDeformation is typically estimated by comparing scans of terrestrial laser scanner (TLS) over the same area but at different time instants. However, such a method can only estimate the difference between two successive surveys, which may be caused by instrumental error and registration error instead of the real deformation, affecting the reliability of deformation monitoring. In order to improve the reliability of TLS-based deformation monitoring, it is necessary to estimate the errors in TLS measurements and determine the precursory displacements that can be detected. In this paper, the error entropy model is exploited for inspecting the threshold value in deformation monitoring, i.e. the minimum detectable deformation magnitude of a TLS. The experimental results demonstrate that deformation greater than the threshold calculated by the proposed error entropy based method can be reliably detected.4 page(s
Harmonic balance method used for harmonics calculation and prediction in power systems
No full textIn power systems harmonic distortion is mainly caused by non-linear loads and power electronics used in different devices and distributed renewable energy systems. In recent years, the presence of non-linear loads and the increasing number of distributed energy resource (DER) units in electrical grids contribute significantly to change the characteristics of voltage and current waveforms in power systems. This paper proposes a novel accurate and effective harmonic analysis method entitled: Harmonic Balance Method (HBM) for power system and distributed energy system (DES). This method can calculate all forms of harmonics generated from nonlinear inductive loads, DER units and saturated transformers; therefore it can provide accurate prediction of harmonic components for active power filters (APFs) and control systems.6 page(s
Secure data-centric access control for smart grid services based on publish/subscribe systems
No full textThe communication systems in existing smart gridsmainly take the request/reply interaction model, in which data access is under the direct control of data producers. This tightly controlled interaction model is not scalable to support complex interactions among smart grid services. On the contrary, the publish/subscribe system features a loose coupling communication infrastructure and allows indirect, anonymous and multicast interactions among smart grid services. The publish/subscribe system can thus support scalable and flexible collaboration among smart grid services. However, the access is not under the direct control of data producers, it might not be easy to implement an access control scheme for a publish/subscribe system. In this article, we propose a Data-Centric Access Control Framework (DCACF) to support secure access control in a publish/subscribe model. This framework helps to build scalable smart grid services, while keeping features of service interactions and data confidentiality at the same time. The data published in our DCACF is encrypted with a fully homomorphic encryption scheme, which allows in-grid homomorphic aggregation of the encrypted data. The encrypted data is accompanied by bloom-filter encoded control policies and access credentials to enable indirect access control. We have analyzed the correctness and security of our DCACF and evaluated its performance in a distributed environment.17 page(s
New geochronology constraints on timing and depth of the ancient earthquakes along the Longmen Shan fault belt, eastern Tibet
No full textPseudotachylyte is an ideal target to directly date ancient earthquake associated with regional faulting. Here we perform step-heating ⁴⁰Ar/³⁹Ar, clay mineral K-Ar, and zircon fission track (ZFT) analyses on the pseudotachylyte samples collected from the Yingxiu-Beichuan coseismic rupture of the Longmen Shan fault belt (LSFB) to provide time constraints for the tectonic evolution of the LSFB during the Indosinian orogeny. ⁴⁰Ar/³⁹Ar results from the matrix show that the frictional melting occurred 226–235 Ma ago. Combined with mylonite dating of the host rock, the age of the ancient earthquakes is constrained at 231–238 Ma, with a formation depth of 10–14 km. As a response to the earthquakes, a series of soft-sediment deformation structures are widely preserved in the Middle and Late Triassic strata along the Yingxiu-Beichuan fault (YBF), indicating that the LSFB was seismically active since the Late Anisian and persisted episodically until the end of the Indosinian orogeny. Both clay mineral K-Ar and ZFT analyses record a younger deformation or alteration with an age of approximately 195 Ma, corresponding to a postcollisional orogeny. These new data represent the first direct evidence of the regional thrusting (YBF) in the central LSFB during the Indosinian orogeny, concurrent with the initial ductile deformation of the western boundary fault. Tectonic inheritance then strongly influenced the evolution of the LSFB as most of the Mesozoic faults are reactivated by major Tertiary tectonic deformations.26 page(s
"It's like DNA you know?": analysing genealogies of listening in Australian hip hop
No full textTheoretical thesis.Bibliography: pages 210-230.Chapter 1. Architects and blueprints -- Chapter 2. Are you listening? -- Chapter 3. Referencing "credible sources" -- Chapter 4. Community, identity, & events -- Chapter 5. Race, skip hop, and diversity -- Chapter 6. Australian hip hop or hip hop in Australia? -- Chapter 7. Facilitating dialogues & directions.From 2011-2016, Australian hip hop has diversified, welcoming local and international attention, in a period some believe is the ‘Golden Age’ (Ziegler 2016) of the genre. Using an ethnographic approach, this thesis provides an exploration of the events and artists involved within this ‘Golden Age’ and analyses the key issues in Australian hip hop, including; identity, race, gender, community, global traits of the genre and local influences. Ten Australian MCs and four key community events provide reference points which demonstrate distinct genealogies of listening that inform analysis, giving a unique snapshot of the genre within an Australian geography. The thesis highlights that the Australian hip hop scene is in a transitional period, as it becomes more mainstream and inclusive of both artists and fans. The result is a distinct local scene that, while building on a core cultural centre shared by hip hop communities worldwide, provides a more inclusive environment of cultural production. Such inclusion is demonstrated through the lack of tension and separation between those who consider hip hop to be a broader culture, and those who engage with hip hop specifically as a genre of music. The thesis documents that even those Australian MCs who do not strongly identify with hip hop culture are embraced by those that do. Inclusion is also demonstrated by accepting approaches to race and gender purported by key artists within the scene. In analysing the shared listening histories of Australian hip hop artists, the thesis exemplifies the importance of genealogies of listening within the genre, demonstrating how hip hop is used by artists in the formation of their identities, whilst also producing unifying traits that define Australian hip hop as it matures and continues to develop as a distinct local hip hop scene.Mode of access: World wide web1 online resource (vi, 283 pages) illustration
Longitudinal fibular deficiency: lower limb function and quality of life of children and young people
No full textTheoretical thesis.Bibliography: pages 60-67.Chapter One. Introduction to longitudinal fibular deficiency -- Chapter Two. Functional consequences of longitudinal fibular deficiency -- Chapter Three. Longitudinal fibular deficiency : a cross-sectional study comparing lower limb function and quality of life of children and young people with unaffected peers -- Chapter Four. Discussion -- References -- Appendices.This thesis builds upon the small evidence-base for longitudinal fibular deficiency in children and young people, specifically in terms of lower limb function and quality of life.To date, research on individuals with longitudinal fibular deficiency has focused on impairments of body functions and structures with minimal investigation of activity limitations and participation restrictions. Studies suggest that affected adults have similar quality of life to published normative values, but little is known about quality of life and lower limb function of children and young people with this condition.Therefore, a cross-sectional study was undertaken exploring these outcomes in 17 affected children compared to 213 unaffected peers. Children and young people reported, on average, significantly reduced lower limb function and quality of life compared to unaffected peers. Knee function in younger children was significantly reduced, however, in young adults it was closer to normal. Ankle function was reduced in children and young people when compared to unaffected peers.Early and individualised clinical assessment of these outcomes appears to be warranted. Further research assessing the effectiveness of treatment interventions, longitudinal studies assessing individual changes over time, and qualitative investigations of a child's function and quality of life are recommended.Mode of access: World wide web1 online resource (x, 89 pages) colour illustration
How does online therapy work?: Exploring skills usage as a mechanism of change in internet-delivered cognitive-behavioural therapy for depression and anxiety
No full textEmpirical thesis.At foot of title: eCentreClinic, Department of Psychology, School of Human Sciences, Macquarie University.Bibliography: pages 150-185.Chapter One. Introduction -- Chapter Two. Study I: Development and preliminary psychometric assessment of a measure of CBT skills usage frequency -- Chapter Three. Study II: Evaluation of the psychometric properties of the FATS in a treatment sample : a single-group open-trial of internet-delivered cognitive-behavioural therapy for depression and general anxiety symptoms -- Chapter Four. Study III: Does skills usage mediate reductions in depression and general anxiety symptoms? A randomised controlled trial of iCBT and mediation analysis -- Chapter Five. Study IV: Predictors and moderators of skills usage in iCBT for depression and anxiety -- Chapter Six. General discussion -- References.Major depression and generalised anxiety disorder (GAD) are common disorders that are often comorbid. Cognitive-Behavioural Therapy (CBT) is an efficacious treatment, which can be delivered online (iCBT), but little is known about its mechanism of therapeutic change. Understanding mechanisms will help improve treatment efficacy and efficiency. A core feature of CBT is teaching patients skills that promote adaptive cognitions and behaviours. However, there is limited evidence indicating that skills usage is a mechanism of change during CBT. The present thesis aims to evaluate the mechanistic role of CBT skills usage on symptoms of depression and GAD during iCBT. The aim of study one was to develop a brief questionnaire assessing CBT skills usage suitable for mechanism research. Responses from 661 participants were subjected to exploratory and confirmatory factor analysis yielding a 12-item measure of CBT skills usage, the Frequency of Actions and Thoughts Scale (FATS). In study two, the FATS was administered during an iCBT course for depression and anxiety (n = 125). Large increases in FATS scores were observed from pre-treatment to post-treatment (d = 0.90), and residualised change scores correlated significantly with residual change scores of symptoms (rs = .28 - .30). The third study utilised a randomised controlled trial investigating the causal relationship between treatment and skills usage. Results indicated that patients receiving iCBT for depression and anxiety (n = 65) reported significantly greater FATS scores (d = 0.58) at the end of treatment compared with a wait-list control group (n = 66). Mediation analysis revealed that symptom reduction was mediated by increased skills usage at the end of treatment. Study four pooled the data from studies two and three, which was used to explore predictors of skills usage. Overall, the results from this research suggest that skills usage is an important mechanism of change in iCBT for depression and GAD.Mode of access: World wide web1 online resource (x, 192 pages
Effects of donor conception, secrecy and anonymity
No full textEmpirical thesis.Running title: Effects of donor conception, secrecy and anonymity.Bibliography: pages 91-116.Donor conception has increasingly become an accepted method to conceive a child. Despite gaining popularity, little attention has been given to the long-term psychosocial implications of the clandestine practice. Previous research has relied on parent reports, young samples, or has other methodological limitations that restrict the generalisability of findings.This study established the effects of donor conception, secrecy and anonymity by surveying 72 donor-conceived adults (9 male, 53 female, 9 unspecified) online. The study first investigated the demographic characteristics of the sample, circumstances of disclosure, and relationships with parents. This study then investigated what motivated donor-conceived people to seek information about, and contact with, their donor. Finally, quality of life, identity, genealogical bewilderment, feelings towards donor conception, and feelings towards information and disclosure, were investigated, including how demographic characteristics, circumstances around disclosure, and relationships impacted each using a series of logistic regressions.The majority of donor-conceived people had sought information about their donor, while a smaller group had sought contact. The most common motivation for doing to was to obtain an accurate medical history. This was particularly important among those who had known of their conception longer. Meanwhile, having a positive relationship with the biological parent was associated with less genealogical bewilderment and positive feelings towards donor conception, while coming from anon-co-parented household was associated with feeling more positively towards disclosure and access to information.The study informs the direction of future research, which can extend the existing findings and increase reliability and generalisability, particularly among males, and persons born from egg and embryo donation. In addition, longitudinal research with donor-conceived people over the course of their lifespan will contribute to understanding the effects at various stages of development.Mode of access: World wide web1 online resource (148 pages) graphs, table
A reverse-genetics approach to low-oxygen tolerance in Arabidopsis
No full textThesis by publication.Bibliography: pages 60-64.1. Introduction -- 2. Materials and methods -- 3. Results -- 4. Discussion -- 5. Conclusion -- References -- Supplementary material.Anoxia causes an energy crisis in plants because oxygen is required to generate ATP. In anoxia-sensitive species, cell death occurs after sustained anoxia through loss of membrane integrity because insufficient energy is available for proton pumping. Arabidopsis vacuolar H+- pyrophosphatase proton pumps (AVP1) reputedly improve survival in anoxia because pyrophosphate substitutes for ATP to maintain proton pumping. Plants overexpressing AVP1 were grown on medium containing 1% or 0.1% sucrose then in anoxia for up to 2 days. RNA was extracted for qPCR during anoxia or plants were given two weeks in normoxia to recover. Survival and dry weight of roots and shoots after two weeks, and resumption of shoot and root growth, were measured over this period. Survival rates post-anoxia were higher on high-sucrose medium but overexpression of AVP1 in roots increased survival, regardless of sucrose supply. However, biomass was only enhanced by AVP1 overexpression in normoxia. AVP1 expression was strongly induced in roots by anoxia, especially on 0.1% sucrose plates, while exogenous sucrose probably inhibited AVP1 induction. AVP1 is a critical component of acclimation to anaerobiosis as its induction in anoxic roots enhances shoot function during an energy crisis. This is an ideal gene target for improved flood tolerance.Mode of access: World wide web1 online resource (73 pages) illustrations (some colour