Data-driven impostor selection for T-norm score normalisation and the background dataset in SVM-based speaker verification

A data-driven background dataset refinement technique was recently proposed for SVM based speaker verification. This method selects a refined SVM background dataset from a set of candidate impostor examples after individually ranking examples by their relevance. This paper extends this technique to the refinement of the T-norm dataset for SVM-based speaker verification. The independent refinement of the background and T-norm datasets provides a means of investigating the sensitivity of SVM-based speaker verification performance to the selection of each of these datasets. Using refined datasets provided improvements of 13% in min. DCF and 9% in EER over the full set of impostor examples on the 2006 SRE corpus with the majority of these gains due to refinement of the T-norm dataset. Similar trends were observed for the unseen data of the NIST 2008 SRE.

Creating and enabling opportunities for increased student participation in experience based learning in professional practice

This paper explores models for enabling increased participation in experience based learning in legal professional practice. Legal placements as part of “for-credit” units offer students the opportunity to develop their professional skills in practice, reflect on their learning and job performance and take responsibility for their career development and planning. In short, work integrated learning (WIL) in law supports students in making the transition from university to practice. Despite its importance, WIL has traditionally taken place in practical legal training courses (after graduation) rather than during undergraduate law courses. Undergraduate WIL in Australian law schools has generally been limited to legal clinics which require intensive academic supervision, partnerships with community legal organisations and government funding. This paper will propose two models of WIL for undergraduate law which may overcome many of the challenges to engaging in WIL in law (which are consistent with those identified generally by the WIL Report). The first is a virtual law placement in which students use technology to complete a real world project in a virtual workplace under the guidance of a workplace supervisor. The second enables students to complete placements in private legal firms, government legal offices, or community legal centres under the supervision of a legal practitioner. The units complement each other by a) creating and enabling placement opportunities for students who may not otherwise have been able to participate in work placement by reason of family responsibilities, financial constraints, visa restrictions, distance etc; and b) enabling students to capitalise on existing work experience. This paper will report on the pilot offering of the units in 2008, the evaluation of the models and changes implemented in 2009. It will conclude that this multi-pronged approach can be successful in creating opportunities for, and overcoming barriers to participation in experiential learning in legal professional practice.

Moving towards a knowledge city : Brisbane's experience in knowledge-based urban development

In the global knowledge economy, knowledge-intensive industries and knowledge workers are extensively seen as the primary factors to improve the welfare and competitiveness of cities. To attract and retain such industries and workers, cities produce knowledge-based urban development strategies, where such strategising is also an important development mechanism for cities and their economies. This paper investigates Brisbane’s knowledge-based urban development strategies that support generation, attraction, and retention of investment and talent. The paper provides a clear understanding on the policy frameworks, and relevant applications of Brisbane’s knowledge-based urban development experience in becoming a prosperous knowledge city.

Factors related to the presentation of thin and thick nodular melanoma from a population-based cancer registry in Queensland Australia

Purpose: Worldwide, the incidence of thick melanoma has not declined, and the nodular melanoma (NM) subtype accounts for nearly 40% of newly-diagnosed thick melanoma. To assess differences between patients with thin (≤2.00 mm) and thick (≥2.01 mm) nodular melanoma, we evaluated factors such as demographics, melanoma detection patterns, tumor visibility, and physician screening for NM alone and compared clinical presentation and anatomic location of NM with superficial spreading melanoma (SSM). Methods We utilized data from a large population-based study of Queensland (Australia) residents diagnosed with melanoma. Queensland residents aged 20 to 75 years with histologically confirmed first primary invasive cutaneous melanoma were eligible for the study, and all questionnaires were conducted by telephone (response rate 77.9%). Results During this four-year period, 369 patients with nodular melanoma were interviewed, of whom 56.7% were diagnosed with tumors ≤ 2.00 mm. Men, older individuals, and those who had not been screened by a physician in the past three years were more likely to have nodular tumors of greater thickness. Thickest nodular melanoma (4 mm+) was also most common in persons who had not been screened by a doctor within the past three years (OR 3.75; 95% CI 1.47-9.59). Forty-six percent of patients with thin nodular melanoma (≤ 2.00 mm) reported a change in color, compared with 64% of patients with thin SSM and 26% of patients with thick nodular melanoma (>2.00 mm). Conclusion Awareness of factors related to earlier detection of potentially fatal nodular melanomas, including the benefits of a physician examination, should be useful in enhancing public and professional education strategies. Particular awareness of clinical warning signs associated with thin nodular melanoma should allow for more prompt diagnosis and treatment of this subtype.

Minimising speaker verification utterance length through confidence based early verification decisions

This paper presents a novel approach of estimating the confidence interval of speaker verification scores. This approach is utilised to minimise the utterance lengths required in order to produce a confident verification decision. The confidence estimation method is also extended to address both the problem of high correlation in consecutive frame scores, and robustness with very limited training samples. The proposed technique achieves a drastic reduction in the typical data requirements for producing confident decisions in an automatic speaker verification system. When evaluated on the NIST 2005 SRE, the early verification decision method demonstrates that an average of 5–10 seconds of speech is sufficient to produce verification rates approaching those achieved previously using an average in excess of 100 seconds of speech.

Walking and sitting in the Australian Antarctic Territory : mobility and imperial space

In 1995 and 1997, two major Australian expeditions travelled to Antarctica. They were the most heavily-reported Antarctican events of their two years: they were charged with the public production of Australian Antarctic spatiality. Both published exploration narratives: Don and Margie McIntyre’s Expedition Icebound generated an illustrated coffee-table book, Two Below Zero: A Year Alone in Antarctica, and the Spirit of Australia South Pole Expedition published its narrative as a video titled Walking on Ice: The History-Making Expedition to the South Pole. Yet, despite the fact that the two polar trips took place during the same period, their spatialities are markedly different. Walking on Ice is a mobile narrative of imperial exploration, while Two Below Zero is a static spatial story of colonial settlement. How polar mobility and relative immobility figure in Australia’s perceptions of, and claim to, nearly half of Antarctica is the focus of this chapter.

Identity-based strong designated verifier signature schemes: Attacks and new construction

A strong designated verifier signature scheme makes it possible for a signer to convince a designated verifier that she has signed a message in such a way that the designated verifier cannot transfer the signature to a third party, and no third party can even verify the validity of a designated verifier signature. We show that anyone who intercepts one signature can verify subsequent signatures in Zhang-Mao ID-based designated verifier signature scheme and Lal-Verma ID-based designated verifier proxy signature scheme. We propose a new and efficient ID-based designated verifier signature scheme that is strong and unforgeable. As a direct corollary, we also get a new efficient ID-based designated verifier proxy signature scheme.

Conceptions of school based youth health nursing : a phenomenographic study

The School Based Youth Health Nurse Program was established in 1999 by the Queensland Government to fund school nurse positions in Queensland state high schools. Schools were required to apply for a School Based Youth Health Nurse during a five-phase recruitment process, managed by the health districts, and rolled out over four years. The only mandatory selection criterion for the position of School Based Youth Health Nurse was registration as a General Nurse and most School Based Youth Health Nurses are allocated to two state high schools. Currently, there are approximately 115 Full Time Equivalent School Based Youth Health Nurse positions across all Queensland state high schools. The literature review revealed an abundance of information about school nursing. Most of the literature came from the United Kingdom and the United States, who have a different model of school nursing to school based youth health nursing. However, there is literature to suggest school nursing is gradually moving from a disease-focused approach to a social view of health. The noticeable number of articles about, for example, drug and alcohol, mental health, and contemporary sexual health issues, is evidence of this change. Additionally, there is a significant the volume of literature about partnerships and collaboration, much of which is about health education, team teaching and how school nurses and schools do health business together. The surfacing of this literature is a good indication that school nursing is aligning with the broader national health priority areas. More particularly, the literature exposed a small but relevant and current body of research, predominantly from Queensland, about school based youth health nursing. However, there remain significant gaps in the knowledge about school based youth health nursing. In particular, there is a deficit about how School Based Youth Heath Nurses understand the experience of school based youth health nursing. This research aimed to reveal the meaning of the experience of school based youth health nursing. The research question was How do School Based Youth Health Nurses’ understand the experience of school based youth health nursing? This enquiry was instigated because the researcher, who had a positive experience of school based youth health nursing, considered it important to validate other School Based Youth Health Nurses’ experiences. Consequently, a comprehensive use of qualitative research was considered the most appropriate manner to explore this research question. Within this qualitative paradigm, the research framework consists of the epistemology of social constructionism, the theoretical perspective of interpretivism and the approach of phenomenography. After ethical approval was gained, purposeful and snowball sampling was used to recruit a sample of 16 participants. In-depth interviews, which were voluntary, confidential and anonymous, were mostly conducted in public venues and lasted from 40-75 minutes. The researcher also kept a researchers journal as another form of data collection. Data analysis was guided by Dahlgren and Fallsbergs’ (1991, p. 152) seven phases of data analysis which includes familiarization, condensation, comparison, grouping, articulating, labelling and contrasting. The most important finding in this research is the outcome space, which represents the entirety of the experience of school based youth health nursing. The outcome space consists of two components: inside the school environment and outside the school environment. Metaphorically and considered as whole-in-themselves, these two components are not discreet but intertwined with each other. The outcome space consists of eight categories. Each category of description is comprised of several sub-categories of description but as a whole, is a conception of school based youth health nursing. The eight conceptions of school based youth health nursing are: 1. The conception of school based youth health nursing as out there all by yourself. 2. The conception of school based youth health nursing as no real backup. 3. The conception of school based youth health nursing as confronted by many barriers. 4. The conception of school based youth health nursing as hectic and full-on. 5. The conception of school based youth health nursing as working together. 6. The conception of school based youth health nursing as belonging to school. 7. The conception of school based youth health nursing as treated the same as others. 8. The conception of school based youth health nursing as the reason it’s all worthwhile. These eight conceptions of school based youth health nursing are logically related and form a staged hierarchical relationship because they are not equally dependent on each other. The conceptions of school based youth health nursing are grouped according to negative, negative and positive and positive conceptions of school based youth health nursing. The conceptions of school based youth health nursing build on each other, from the bottom upwards, to reach the authorized, or the most desired, conception of school based youth health nursing. This research adds to the knowledge about school nursing in general but especially about school based youth health nursing specifically. Furthermore, this research has operational and strategic implications, highlighted in the negative conceptions of school based youth health nursing, for the School Based Youth Health Nurse Program. The researcher suggests the School Based Youth Health Nurse Program, as a priority, address the operational issues The researcher recommends a range of actions to tackle issues and problems associated with accommodation and information, consultations and referral pathways, confidentiality, health promotion and education, professional development, line management and School Based Youth Health Nurse Program support and school management and community. Strategically, the researcher proposes a variety of actions to address strategic issues, such as the School Based Youth Health Nurse Program vision, model and policy and practice framework, recruitment and retention rates and evaluation. Additionally, the researcher believes the findings of this research have the capacity to spawn a myriad of future research projects. The researcher has identified the most important areas for future research as confidentiality, information, qualifications and health outcomes.

A distributed knowledge management infrastructure based on a Topic Map grid

Modern enterprise knowledge management systems typically require distributed approaches and the integration of numerous heterogeneous sources of information. A powerful foundation for these tasks can be Topic Maps, which not only provide a semantic net-like knowledge representation means and the possibility to use ontologies for modelling knowledge structures, but also offer concepts to link these knowledge structures with unstructured data stored in files, external documents etc. In this paper, we present the architecture and prototypical implementation of a Topic Map application infrastructure, the ‘Topic Grid’, which enables transparent, node-spanning access to different Topic Maps distributed in a network.

Treadmill adaptation and verification of self-selected walking speed : a protocol for children

The term self-selected (i.e., individual or comfortable walking pace or speed) is commonly used in the literature (Frost, Dowling, Bar-Or, & Dyson, 1997; Jeng, Liao, Lai, & Hou, 1997; Wergel-Kolmert & Wohlfart, 1999; Maltais, Bar-Or, Pienynowski, & Galea, 2003; Browning & Kram, 2005; Browning, Baker, Herron, & Kram, 2006; Hills, Byrne, Wearing, & Armstrong, 2006) and is identified as the most efficient walking speed, with increased efficiency defined by lower oxygen uptake (VO^sub 2^) per unit mechanical work (Hoyt & Taylor, 1981; Taylor, Heglund, & Maloiy, 1982; Hreljac, 1993). [...] assessing individual and group differences in metabolic energy expenditure using oxygen uptake requires individuals to be comfortable with, and able to accommodate to, the equipment.

Within- and between-day repeatability and variability in children's physiological responses during submaximal treadmill exercise

The purpose of this study was to verify within- and between-day repeatability and variability in children's oxygen uptake (VO^sub 2^), gross economy (GE; VO^sub 2^ divided by speed) and heart rate (HR) during treadmill walking based on self-selected speed (SS). Fourteen children (10.1 ± 1.4 years) undertook three testing sessions over 2 days in which four walking speeds, including SS were tested. Within- and between-day repeatability were assessed using the Bland and Altman method, and coefficients of variability (CV) were determined for each child across exercise bouts and averaged to obtain a mean group CV value for VO^sub 2^, GE, and HR per speed. Repeated measures analysis of variance showed no statistically significant differences in within- or between-day CV for VO^sub 2^, GE, or HR at any speed. Repeatability within- and between-day for VO^sub 2^, GE, and HR for all speeds was verified. These results suggest that submaximal VO^sub 2^ during treadmill walking is stable and reproducible at a range of speeds based on children's SS.

Tag based collaborative filtering for recommender systems

Collaborative tagging can help users organize, share and retrieve information in an easy and quick way. For the collaborative tagging information implies user’s important personal preference information, it can be used to recommend personalized items to users. This paper proposes a novel tag-based collaborative filtering approach for recommending personalized items to users of online communities that are equipped with tagging facilities. Based on the distinctive three dimensional relationships among users, tags and items, a new similarity measure method is proposed to generate the neighborhood of users with similar tagging behavior instead of similar implicit ratings. The promising experiment result shows that by using the tagging information the proposed approach outperforms the standard user and item based collaborative filtering approaches.

Collaborative Filtering Recommender Systems based on Popular Tags

The social tags in web 2.0 are becoming another important information source to profile users' interests and preferences for making personalized recommendations. However, the uncontrolled vocabulary causes a lot of problems to profile users accurately, such as ambiguity, synonyms, misspelling, low information sharing etc. To solve these problems, this paper proposes to use popular tags to represent the actual topics of tags, the content of items, and also the topic interests of users. A novel user profiling approach is proposed in this paper that first identifies popular tags, then represents users’ original tags using the popular tags, finally generates users’ topic interests based on the popular tags. A collaborative filtering based recommender system has been developed that builds the user profile using the proposed approach. The user profile generated using the proposed approach can represent user interests more accurately and the information sharing among users in the profile is also increased. Consequently the neighborhood of a user, which plays a crucial role in collaborative filtering based recommenders, can be much more accurately determined. The experimental results based on real world data obtained from Amazon.com show that the proposed approach outperforms other approaches.

Design of self-turning controllers for two terminal HVDC link

This paper presents the design of self-tuning controllers for a two terminal HVDC link. The controllers are designed utilizing a novel discrete-time converter model based on multirate sampling. The nature of converter firing system necessitates the development of a two-step ahead self-tuning control strategy. A two terminal HVDC system study has been carried out to show the effectiveness of the control strategies proposed which include the design of minimum variance controller, pole assigned controller and PLQG controller. The coordinated control of a two terminal HVDC system has been established deriving the signal from inverter end current and voltage which has been estimated based on the measurements of rectifier end quantities only realized through the robust reduced order observer. A well known scaled down sample system data has been selected for studies and the controllers designed have been tested for worst conditions. The performance of self-tuning controllers has been evaluated through digital simulation.

Measurement properties of the Australian Women's Activity Survey

Purpose: The Australian Women’s Activity Survey (AWAS) was developed based on a systematic review and qualitative research on how to measure activity patterns of women with young children (WYC). AWAS assesses activity performed across five domains (planned activities, employment, childcare, domestic responsibilities and transport), and intensity levels (sitting, light-intensity, brisk walking, moderate-intensity and vigorous-intensity) in a typical week in the past month. The purpose of this study was to assess the test-retest reliability and criterion validity of the AWAS. Methods: WYC completed the AWAS on two occasions 7-d apart (test-retest reliability protocol) and/or wore an MTI ActiGraph accelerometer for 7-d in between (validity protocol). Forty WYC (mean age 35 ± 5yrs) completed the test-retest reliability protocol and 75 WYC (mean age 33 ± 5yrs) completed the validity protocol. Interclass Correlation Coefficients (ICC) between AWAS administrations and Spearman’s Correlation Coefficients (rs) between AWAS and MTI data were calculated. Results: AWAS showed good test-retest reliability (ICC=0.80 (0.65-0.89)) and acceptable criterion validity (rs= 0.28, p=0.01) for measuring weekly health-enhancing physical activity. AWAS also provided repeatable and valid estimates of sitting time (test-retest reliability ICC=0.42 (0.13-0.64), and criterion validity (rs= 0.32, p=0.006)). Conclusion: The measurement properties of the AWAS are comparable to those reported for existing self-report measures of physical activity. However, AWAS offers a more comprehensive and flexible alternative for accurately assessing different domains and intensities of activity relevant to WYC. Future research should investigate whether the AWAS is a suitable measure of intervention efficacy by examining its sensitivity to change.