Assessing of circuit breaker restrike risks using computer simulation and wavelet analysis

A breaker restrike is an abnormal arcing phenomenon, leading to a possible breaker failure. Eventually, this failure leads to interruption of the transmission and distribution of the electricity supply system until the breaker is replaced. Before 2008, there was little evidence in the literature of monitoring techniques based on restrike measurement and interpretation produced during switching of capacitor banks and shunt reactor banks in power systems. In 2008 a non-intrusive radiometric restrike measurement method and a restrike hardware detection algorithm were developed by M.S. Ramli and B. Kasztenny. However, the limitations of the radiometric measurement method are a band limited frequency response as well as limitations in amplitude determination. Current restrike detection methods and algorithms require the use of wide bandwidth current transformers and high voltage dividers. A restrike switch model using Alternative Transient Program (ATP) and Wavelet Transforms which support diagnostics are proposed. Restrike phenomena become a new diagnostic process using measurements, ATP and Wavelet Transforms for online interrupter monitoring. This research project investigates the restrike switch model Parameter „A. dielectric voltage gradient related to a normal and slowed case of the contact opening velocity and the escalation voltages, which can be used as a diagnostic tool for a vacuum circuit-breaker (CB) at service voltages between 11 kV and 63 kV. During current interruption of an inductive load at current quenching or chopping, a transient voltage is developed across the contact gap. The dielectric strength of the gap should rise to a point to withstand this transient voltage. If it does not, the gap will flash over, resulting in a restrike. A straight line is fitted through the voltage points at flashover of the contact gap. This is the point at which the gap voltage has reached a value that exceeds the dielectric strength of the gap. This research shows that a change in opening contact velocity of the vacuum CB produces a corresponding change in the slope of the gap escalation voltage envelope. To investigate the diagnostic process, an ATP restrike switch model was modified with contact opening velocity computation for restrike waveform signature analyses along with experimental investigations. This also enhanced a mathematical CB model with the empirical dielectric model for SF6 (sulphur hexa-fluoride) CBs at service voltages above 63 kV and a generalised dielectric curve model for 12 kV CBs. A CB restrike can be predicted if there is a similar type of restrike waveform signatures for measured and simulated waveforms. The restrike switch model applications are used for: computer simulations as virtual experiments, including predicting breaker restrikes; estimating the interrupter remaining life of SF6 puffer CBs; checking system stresses; assessing point-on-wave (POW) operations; and for a restrike detection algorithm development using Wavelet Transforms. A simulated high frequency nozzle current magnitude was applied to an Equation (derived from the literature) which can calculate the life extension of the interrupter of a SF6 high voltage CB. The restrike waveform signatures for a medium and high voltage CB identify its possible failure mechanism such as delayed opening, degraded dielectric strength and improper contact travel. The simulated and measured restrike waveform signatures are analysed using Matlab software for automatic detection. Experimental investigation of a 12 kV vacuum CB diagnostic was carried out for the parameter determination and a passive antenna calibration was also successfully developed with applications for field implementation. The degradation features were also evaluated with a predictive interpretation technique from the experiments, and the subsequent simulation indicates that the drop in voltage related to the slow opening velocity mechanism measurement to give a degree of contact degradation. A predictive interpretation technique is a computer modeling for assessing switching device performance, which allows one to vary a single parameter at a time; this is often difficult to do experimentally because of the variable contact opening velocity. The significance of this thesis outcome is that it is a non-intrusive method developed using measurements, ATP and Wavelet Transforms to predict and interpret a breaker restrike risk. The measurements on high voltage circuit-breakers can identify degradation that can interrupt the distribution and transmission of an electricity supply system. It is hoped that the techniques for the monitoring of restrike phenomena developed by this research will form part of a diagnostic process that will be valuable for detecting breaker stresses relating to the interrupter lifetime. Suggestions for future research, including a field implementation proposal to validate the restrike switch model for ATP system studies and the hot dielectric strength curve model for SF6 CBs, are given in Appendix A.

Data mining traditional Chinese medicine (TCM) lessons learnt from mining in law and allopathic medicine

Key decisions at the collection, pre-processing, transformation, mining and interpretation phase of any knowledge discovery from database (KDD) process depend heavily on assumptions and theorectical perspectives relating to the type of task to be performed and characteristics of data sourced. In this article, we compare and contrast theoretical perspectives and assumptions taken in data mining exercises in the legal domain with those adopted in data mining in TCM and allopathic medicine. The juxtaposition results in insights for the application of KDD for Traditional Chinese Medicine.

The use of computerised simulators for training of transthoracic and transoesophageal echocardiography. The future of echocardiographic training?

Echocardiography is the commonest form of non-invasive cardiac imaging and is fundamental to patient management. However, due to its methodology, it is also operator dependent. There are well defined pathways in training and ongoing accreditation to achieve and maintain competency. To satisfy these requirements, significant time has to be dedicated to scanning patients, often in the time pressured clinical environment. Alternative, computer based training methods are being considered to augment echocardiographic training. Numerous advances in technology have resulted in the development of interactive programmes and simulators to teach trainees the skills to perform particular procedures, including transthoracic and transoesophageal echocardiography. 82 sonographers and TOE proceduralists utilised an echocardiographic simulator and assessed its utility using defined criteria. 40 trainee sonographers assessed the simulator and were taught how to obtain an apical 2 chamber (A2C) view and image the superior vena cava (SVC). 100% and 88% found the simulator useful in obtaining the SVC or A2C view respectively. All users found it easy to use and the majority found it helped with image acquisition and interpretation. 42 attendees of a TOE training day utilising the simulator assessed the simulator with 100% finding it easy to use, as well as the augmented reality graphics benefiting image acquisition. 90% felt that it was realistic. This study revealed that both trainee sonographers and TOE proceduralists found the simulation process was realistic, helped in image acquisition and improved assessment of spatial relationships. Echocardiographic simulators may play an important role in the future training of echocardiographic skills.

Preparing culturally and linguistically diverse nursing students for clinical practice in the health care setting

The number of culturally and linguistically diverse (CALD) students seeking enrollment in higher education courses in Western countries where English is the predominant language has grown considerably in the past decade, especially in undergraduate health care courses. When enrolled in nursing courses, students are required to complete clinical placements. Such experiences can create significant challenges for CALD students where language, cultural differences, and interpretation of cultural norms complicate the learning process. To assist CALD nursing students to transition successfully, an extracurricular integrated curriculum program was developed and implemented at a university in Queensland, Australia. The program is a series of interactive workshops based on the principles of caring pedagogy and student-centered learning. The program applies strategies that combine small-group discussions with peers, role-plays, and interactions with final-year nursing student volunteers. Evaluation of the program suggests it has assisted most of the students surveyed to be successful in their clinical studies.

Criminal desistance : life opportunities and hermeneutic circles of self-definition

The emic perspective of criminal desistance (ex-offenders’ personal explanations of how they gave up crime) is largely ignored by criminology. This thesis attempts to address this absence of the storyteller’s perspective by inviting desisters to participate in the exploration and interpretation of their individual desistance journeys. Significant attention is drawn to the importance of philosophical self-enquiry to personal change. This detailed journey through the desistance stories of five ex-offenders has produced an emphatic re-statement of the need for the non-judgemental listener as the beginning point of cathartic healing in damaged lives.

Synthesizing form and data : developing practices for student engagement and learning

We explore the relationship between form and data as a design agenda and learning strategy for novice visual information designers. Our students are university seniors in digital, visual design but novices to information design, manipulation and interpretation. We describe design strategies developed to scaffold sophisticated aesthetic and conceptual engagement despite limited understanding of the domain of designing with information. These revolve around an open-ended design project where students created a physical design from data of their choosing and research. The accompanying learning strategies concern this relationship between data and form to investigate it materially, formally and through ideation. Exemplifying student works that cross media and design domains are described.

Better half-dead than read? The Mezzomorto cases and their implications for literary culture in the 1930s

This article focusses on the two libel cases arising from Brian Penton's review of Vivian Crockett's novel Mezzomorto for the Bulletin in 1934, viewing them as points of entry into Australian literary politics in the 1930s, and as windows on to one of the most enduring and interesting feuds in Australian literary culture, that between P.R. 'Inky' Stephensen, self-styled 'Bunyip Critic,' and Brian Penton, arch exponent of 'destructive criticism' and scourge of parochial pretension. The cases are particularly interesting for what they reveal about the evolving positions of two influential figures in Australian writing of the 1930s and 1940s. They also play in to contemporary debates about the state and status of 'literature' in Australia. And while Penton's biographer Patrick Buckridge avers that the cases did not impact on any of the larger contemporary literary issues (meaning censorship and free speech), a case may be made for the significance of the libel actions in the context of attempts to establish an industrial and cultural presence for a diverse range of Australian writing.

The effect of repeated loading and freeze-thaw cycling on immature bovine thoracic motion segment stiffness

There is growing interest in the biomechanics of ‘fusionless’ implant constructs used for deformity correction in the thoracic spine, however, there are questions over the comparability of in vitro biomechanical studies from different research groups due to the various methods used for specimen preparation, testing and data collection. The aim of this study was to identify the effect of two key factors on the stiffness of immature bovine thoracic spine motion segments: (i) repeated cyclic loading and (ii) multiple freeze-thaw cycles, to aid in the planning and interpretation of in vitro studies. Two groups of thoracic spine motion segments from 6-8 week old calves were tested in flexion/extension, right/left lateral bending, and right/left axial rotation under moment control. Group (A) were tested with continuous repeated cyclic loading for 500 cycles with data recorded at cycles 3, 5, 10, 25, 50, 100, 200, 300, 400 and 500. Group (B) were tested after each of five freeze-thaw sequences, with data collected from the 10th load cycle in each sequence. Group A: Flexion/extension stiffness reduced significantly over the 500 load cycles (-22%; P=0.001), but there was no significant change between the 5th and 200th load cycles. Lateral bending stiffness decreased significantly (-18%; P=0.009) over the 500 load cycles, but there was no significant change in axial rotation stiffness (P=0.137). Group B: There was no significant difference between mean stiffness over the five freeze-thaw sequences in flexion/extension (P=0.813) and a near significant reduction in mean stiffness in axial rotation (-6%; P=0.07). However, there was a statistically significant increase in stiffness in lateral bending (+30%; P=0.007). Comparison of in vitro testing results for immature thoracic bovine spine segments between studies can be performed with up to 200 load cycles without significant changes in stiffness. However, when testing protocols require greater than 200 cycles, or when repeated freeze-thaw cycles are involved, it is important to account for the effect of cumulative load and freeze-thaw cycles on spine segment stiffness.

Conceptualisation and enactment of critical literacy for senior high school EAL learners in Queensland, Australia : commitments, constraints and contradictions

This case study examined four teachers' understandings and teaching of Critical Literacy with senior English as an Additional Language (EAL) learners in two Queensland high schools. Despite continuous, rapid curriculum change in Australia and efforts to diminish Critical Literacy, the four teachers continued to feature it successfully in their teaching with often marginalised learners. They used critical literacy to provide access to and critique dominant language codes, and to draw on learners' diverse experiences. To a lesser extent, the teachers created opportunities for redesigning dominant texts. Implications are important for policy production and interpretation, school planning and teacher professional development.

How to plan and implement an environmental education program for a conservation area : lessons from Australia and Borneo

The Augo Wetland Forest Park, along with other conservation areas around the world, provides an opportunity for a personal connection with the natural world - an opportunity for creating ways to convince people to reverse the degradation of the planet. In this presentation I use the settings approach, as used by the World Health Organisation in health promotion, as a framework. The WHO’s 1986 Ottawa Charter states that "Health is created and lived by people within the settings of their everyday life; where they learn, work, play, and love." I argue that, similarly, a conservation area provides a setting for people to connect with environmental issues and can be the place where positive behaviours and actions for the environment are created and enacted. In a wired and virtual world, such settings may be the only opportunity some people, especially children, get to connect with the environment. An evidence-based, intentionally designed and implemented environmental education program enhances the opportunities for the personal connection and subsequent action. Planning and implementing an Environmental education program for a conservation area requires an understanding of the principles of three domains: • Environmental Communication • Environmental Education • Environmental Interpretation In this presentation I define these domains and demonstrate how they become interdependent within the context of a particular setting such as a conservation area. I outline the principles of each domain and demonstrate how they can be enacted with reference to environmental education program case studies from settings in Australia and Borneo. The first case study is based around a proposal for a planned residential community at Eden’s Crossing, in Brisbane’s high growth Western corridor. The setting featured a number of important natural and heritage conservation characteristics and the developer wanted to be pro-active in informing the market what this development aims to achieve in terms of innovative community and environmental objectives. By designing an education and interpretation program in line with best practice education and interpretation principles the developers would be assisted in their efforts to build community, preserve heritage, and facilitate environmentally sensitive lifestyles for the future residents of Eden’s Crossing. Above all, the strategy focused on advancing sustainability in a way that made the Eden’s Crossing greenfield development significantly greener. It did this by interacting with prospective purchasers, and building knowledge about sustainability with a view to shaping the future community of Eden’s Crossing in terms of attitudes and behaviours. The second case study is based around the development of the Rainforest Interpretation Centre (RIC), now renamed the Rainforest Discovery Centre, an environmental education facility managed by the Sabah Forestry Department (SFD) and located at the edge of the Kabili-Sepilok Forest Reserve in the East Malaysian state of Sabah (Borneo). This setting is of paramount importance for biodiversity conservation and research and a vital habitat for orang utan. As an Environmental Education Consultant I was tasked with developing an environmental education program for this setting as part of the SFD’s long- term strategy towards sustainable forest management. By employing the principles of Environmental Education and Environmental Interpretation I designed and implemented a program with three major components: • an environmental education component for visiting primary and secondary school groups. • an environmental education component for in-service and pre-service teachers and teacher educators. • a public awareness and environmental interpretation component which caters for the general public and tourists. From these modest beginnings the program has expanded and new facilities have been developed to meet the demands of visitors, teachers and students. The effectiveness of the program can be traced back to the grounding in the principles of best practice environmental education, communication and interpretation.

Male and female cyclist and driver perceptions of crash risk

Many drivers and non-cyclists perceive cycling as an extremely risky activity with women in particular being concerned about the risk of injury. The low rates of cycling participation by women pose a threat to the achievement of government targets for cycling participation and restrict the potential transport, health and environmental benefits that increased levels of cycling could provide. This study seeks to extend earlier research in gender and cycling by comparing the risks perceived by female and male cyclists and drivers in specific on-road situations while accounting for other potentially gender-related factors such as travel patterns and experience, perceived skill, and risk taking behaviors. In an online survey, 444 regular cyclists and 151 (non-cyclist) car drivers rated the level of risk in six situations: Failing to yield; Going through a red light; Not signaling when turning; Swerving; Tailgating; and Not checking traffic. The study found that the higher levels of risk perceived by women are not completely accounted for by differences in cycling patterns or perceptions of skill. Compared to their male counterparts, female cyclists and car drivers had similarly elevated perceptions of risk suggesting that these gender differences are not specific to cycling, but reflect wider differences in risk perception. Not all of the gender differences were consistent across cyclists and drivers. Higher levels of perceived skill were evident for male cyclists but not for male car drivers. Further research is needed to explore the robustness and interpretation of this finding.

Reliability and criterion-related validity with a smartphone used in timed-up-and-go test

Background The capacity to diagnosys, quantify and evaluate movement beyond the general confines of a clinical environment under effectiveness conditions may alleviate rampant strain on limited, expensive and highly specialized medical resources. An iPhone 4® mounted a three dimensional accelerometer subsystem with highly robust software applications. The present study aimed to evaluate the reliability and concurrent criterion-related validity of the accelerations with an iPhone 4® in an Extended Timed Get Up and Go test. Extended Timed Get Up and Go is a clinical test with that the patient get up from the chair and walking ten meters, turn and coming back to the chair. Methods A repeated measure, cross-sectional, analytical study. Test-retest reliability of the kinematic measurements of the iPhone 4® compared with a standard validated laboratory device. We calculated the Coefficient of Multiple Correlation between the two sensors acceleration signal of each subject, in each sub-stage, in each of the three Extended Timed Get Up and Go test trials. To investigate statistical agreement between the two sensors we used the Bland-Altman method. Results With respect to the analysis of the correlation data in the present work, the Coefficient of Multiple Correlation of the five subjects in their triplicated trials were as follows: in sub-phase Sit to Stand the ranged between r = 0.991 to 0.842; in Gait Go, r = 0.967 to 0.852; in Turn, 0.979 to 0.798; in Gait Come, 0.964 to 0.887; and in Turn to Stand to Sit, 0.992 to 0.877. All the correlations between the sensors were significant (p < 0.001). The Bland-Altman plots obtained showed a solid tendency to stay at close to zero, especially on the y and x-axes, during the five phases of the Extended Timed Get Up and Go test. Conclusions The inertial sensor mounted in the iPhone 4® is sufficiently reliable and accurate to evaluate and identify the kinematic patterns in an Extended Timed Get and Go test. While analysis and interpretation of 3D kinematics data continue to be dauntingly complex, the iPhone 4® makes the task of acquiring the data relatively inexpensive and easy to use.

In-vehicle filming of driver fatigue on YouTube: Vlogs, crashes and bad advice

Background: Driver fatigue contributes to 15-30% of crashes, however it is difficult to objectively measure. Fatigue mitigation relies on driver self-moderation, placing great importance on the necessity for road safety campaigns to engage with their audience. Popular self-archiving website YouTube.com is a relatively unused source of public perceptions. Method: A systematic YouTube.com search (videos uploaded 2/12/09 - 2/12/14) was conducted using driver fatigue related search terms. 442 relevant videos were identified. In-vehicle footage was separated for further analysis. Video reception was quantified in terms of number of views, likes, comments, dislikes and times duplicated. Qualitative analysis of comments was undertaken to identify key themes. Results: 4.2% (n=107) of relevant uploaded videos contained in-vehicle footage. Three types of videos were identified: (1) dashcam footage (n=82); (2) speaking directly to the camera - vlogs (n=16); (3) passengers filming drivers (n=9). Two distinct types of comments emerged, those directly relating to driver fatigue and those more broadly about the video or its uploader. Driver fatigue comments included: attribution of behaviour cause, emotion experienced when watching the video and personal advice on staying awake while driving. Discussion: In-vehicle footage related to driver fatigue is prevalent on YouTube.com and is actively engaged with by viewers. Comments were mixed in terms of criticism and sympathy for drivers. Willingness to share advice on staying awake suggests driver fatigue may be seen as a common yet controllable occurrence. This project provides new insight into driver fatigue perception, which may be considered by safety authorities when designing education campaigns.

Site and gender specificity of inheritance of bone mineral density

Differences in genetic control of BMD by skeletal sites and genders were examined by complex segregation analysis in 816 members of 147 families with probands with extreme low BMD. Spine BMD correlated more strongly in male-male comparisons and hip BMD in female-female comparisons, consistent with gender- and site-specificity of BMD heritability. Introduction: Evidence from studies in animals and humans suggests that the genetic control of bone mineral density (BMD) may differ at different skeletal sites and between genders. This question has important implications for the design and interpretation of genetic studies of osteoporosis. Methods: We examined the genetic profile of 147 families with 816 individuals recruited through probands with extreme low BMD (T-score < −2.5, Z-score < −2.0). Complex segregation analysis was performed using the Pedigree Analysis Package. BMD was measured by DXA at both lumbar spine (L1-L4) and femoral neck. Results: Complex segregation analysis excluded purely monogenic and environmental models of segregation of lumbar spine and femoral neck BMD in these families. Pure polygenic models were excluded at the lumbar spine when menopausal status was considered as a covariate, but not at the femoral neck. Mendelian models with a residual polygenic component were not excluded. These models were consistent with the presence of a rare Mendelian genotype of prevalence 3–19 %, causing high BMD at the hip and spine in these families, with additional polygenic effects. Total heritability range at the lumbar spine was 61–67 % and at the femoral neck was 44–67 %. Significant differences in correlation of femoral neck and lumbar spine BMD were observed between male and female relative pairs, with male-male comparisons exhibiting stronger lumbar spine BMD correlation than femoral neck, and female-female comparisons having greater femoral neck BMD correlation than lumbar spine. These findings remained true for parent-offspring correlations when menopausal status was taken into account. The recurrence risk ratio for siblings of probands of a Z-score < −2.0 was 5.4 at the lumbar spine and 5.9 at the femoral neck. Conclusions: These findings support gender- and site-specificity of the inheritance of BMD. These results should be considered in the design and interpretation of genetic studies of osteoporosis.

Style and Readability in Football Texts

Tutkielmassa tarkastellaan jalkapallokieltä erikoiskielenä tyylintutkimuksen näkökulmasta. Tutkimusaineistoksi on valittu kuusi noin 2000 sanan pituista otosta erilaisista jalkapalloa käsittelevistä teksteistä, joista kolme on kirjoitettu suomeksi ja kolme englanniksi. Työssä pyritään selvittämään, mitä eroa yleiskieltä lähestyvillä ja erikoiskieliksi katsottavilla jalkapalloteksteillä on ja kuinka jalkapallokieli erikoiskielenä vertautuu muihin erikoiskieliin. Tutkimukseen sisältyy lisäksi tutkittuja tekstejä koskeva kyselyosio. Lopuksi pohditaan sitä, mitä merkitystä saadulla tiedolla on kääntämiselle. Käytetty tutkimustapa on luonteeltaan melko kvantitatiivinen, ja se pohjautuu pitkälti käsityksiin hyvästä luettavuudesta. Ensin teksteistä lasketaan keskimääräinen lausepituus, eri sanaluokkien frekvenssejä sekä aktiivi- ja passiivimuodossa olevien verbien suhde. Tämän jälkeen pohditaan, mitä merkitystä tuloksilla voisi olla tekstien tyylille ja luettavuudelle. Tekstit annetaan vielä luettaviksi koehenkilöille, jotka vastaavat tekstit luettuaan tyyliä ja luettavuutta koskevaan kyselyyn. Lopulta kyselyn tuloksia verrataan tyylianalyysin avulla saatuihin tuloksiin. Analysoiduista teksteistä saadut tulokset eivät vastaa aiemmin erikoiskielistä saatuja tuloksia, eikä jalkapallon erikoiskielestä synny kiistatonta kokonaiskuvaa. Substantiivien määrä etenkin suomenkielisissä jalkapalloteksteissä on niin suuri, että se vaikuttaa tekstien luettavuuteen ja tyyliin. Teksteissä käytetyt virkkeet eivät toisaalta ole kovin pitkiä tai monimutkaisia, mikä yhdistää jalkapallokieltä ja muissa urheilulajeissa käytettyä kieltä. Englanninkielisissä teksteissä käytetään enemmän adjektiiveja ja anaforista viittausta kuin suomenkielisissä, mikä on huomionarvoista käännöksissä, koska suomalaisilla kirjoittajilla vaikuttaisi analysoitujen tekstien perusteella todellakin olevan taipumusta substantiivien liialliseen käyttöön. Kyselystä saadut tulokset eivät vastaa frekvenssianalyyseistä saatuja tuloksia, ja kysely paljastaa myös sen, ettei lukunopeus ole aina luotettava luettavuuden mittari. Jos aihetta tutkittaisiin lisää, olisi tutkimusaineiston syytä olla laajempi, jotta saataisiin kouriintuntuvampia tuloksia. Mikäli tutkitaan myös tekstien luettavuutta, on syytä ottaa huomioon, ettei lukunopeuden mittaaminen ole välttämättä luotettava menetelmä luettavuuden toteamiseksi. Avainsanat Nyckelord Keywords Tyyli, luettavuus, rekisteri, tekstilaji, erikoiskielet, tyylintutkimus Säilytyspaikka Förvaringställe Where deposited Käännöstieteen laitoksen kirjasto