Discriminative optimisation of the figure of merit for phonetic spoken term detection

This work proposes to improve spoken term detection (STD) accuracy by optimising the Figure of Merit (FOM). In this article, the index takes the form of phonetic posterior-feature matrix. Accuracy is improved by formulating STD as a discriminative training problem and directly optimising the FOM, through its use as an objective function to train a transformation of the index. The outcome of indexing is then a matrix of enhanced posterior-features that are directly tailored for the STD task. The technique is shown to improve the FOM by up to 13% on held-out data. Additional analysis explores the effect of the technique on phone recognition accuracy, examines the actual values of the learned transform, and demonstrates that using an extended training data set results in further improvement in the FOM.

Phylogeographic reconstruction of a bacterial species with high levels of lateral gene transfer

Background Phylogeographic reconstruction of some bacterial populations is hindered by low diversity coupled with high levels of lateral gene transfer. A comparison of recombination levels and diversity at seven housekeeping genes for eleven bacterial species, most of which are commonly cited as having high levels of lateral gene transfer shows that the relative contributions of homologous recombination versus mutation for Burkholderia pseudomallei is over two times higher than for Streptococcus pneumoniae and is thus the highest value yet reported in bacteria. Despite the potential for homologous recombination to increase diversity, B. pseudomallei exhibits a relative lack of diversity at these loci. In these situations, whole genome genotyping of orthologous shared single nucleotide polymorphism loci, discovered using next generation sequencing technologies, can provide very large data sets capable of estimating core phylogenetic relationships. We compared and searched 43 whole genome sequences of B. pseudomallei and its closest relatives for single nucleotide polymorphisms in orthologous shared regions to use in phylogenetic reconstruction. Results Bayesian phylogenetic analyses of >14,000 single nucleotide polymorphisms yielded completely resolved trees for these 43 strains with high levels of statistical support. These results enable a better understanding of a separate analysis of population differentiation among >1,700 B. pseudomallei isolates as defined by sequence data from seven housekeeping genes. We analyzed this larger data set for population structure and allele sharing that can be attributed to lateral gene transfer. Our results suggest that despite an almost panmictic population, we can detect two distinct populations of B. pseudomallei that conform to biogeographic patterns found in many plant and animal species. That is, separation along Wallace's Line, a biogeographic boundary between Southeast Asia and Australia. Conclusion We describe an Australian origin for B. pseudomallei, characterized by a single introduction event into Southeast Asia during a recent glacial period, and variable levels of lateral gene transfer within populations. These patterns provide insights into mechanisms of genetic diversification in B. pseudomallei and its closest relatives, and provide a framework for integrating the traditionally separate fields of population genetics and phylogenetics for other bacterial species with high levels of lateral gene transfer.

Measuring driver responses at railway level crossings

Railway level crossings are amongst the most complex of road safety control systems, due to the conflicts between road vehicles and rail infrastructure, trains and train operations. Driver behaviour at railway crossings is the major collision factor. The main objective of the present paper was to evaluate the existing conventional warning devices in relation to driver behaviour. The common conventional warning devices in Australia are a stop sign (passive), flashing lights and a half boom-barrier with flashing lights (active). The data were collected using two approaches, namely: field video recordings at selected sites and a driving simulator in a laboratory. This paper describes and compares the driver response results from both the field survey and the driving simulator. The conclusion drawn is that different types of warning systems resulted in varying driver responses at crossings. The results showed that on average driver responses to passive crossings were poor when compared to active ones. The field results were consistent with the simulator results for the existing conventional warning devices and hence they may be used to calibrate the simulator for further evaluation of alternative warning systems.

Grassroots leaders: Reclaiming 'Native Leadership' as content for enhancing formal leadership preparation

It is almost a truism that persons who occupy formal bureaucratic positions in schools may not actually be leaders if they were not role incumbents in a bureaucracy. It is also clear from studies of grassroots leaders that without the qualities of skills of leadership no one would follow them because they have no formal, hierarchical role upon which others were dependent to them. One of the reasons for re-examining the nature of grassroots leaders is to attempt to recapture those tactics or strategies which might be reconceptualized and utilized within more formal settings so that role dependent leadership becomes more effectual and trustworthy than one that is totally dependent on role authority. This reasoning is especially a critical need if there is a desire to work towards more democratic and collaborative working arrangements between leaders and followers, and where more flexible and dynamic relationships promise higher levels of commitment and productivity. Hecksher (1994) speaks of such a reconceptualization as part of a shift from an emphasis on power to one centered on influence. This paper examines the nature of leadership before it was subjected to positivistic science and later behavioural studies. This move follows the advice of Heilbrunn (1996) who trenchantly observed that for leadership studies to grow as a discipline, “it will have to cast a wider net” (p.11). Willis et. Al. (2008) make a similar point when they lament that social scientist have forced favoured understanding bureaucracies rather than grassroots community organizations, yet much can be gained by being aware of the tactics and strategies used by grassroots leaders who depend on influence as opposed to power. This paper, then, aims to do this by posing a tentative model of grassroots leadership and then considering how this model might inform and be used by those responsible for developing school leaders.

Mothers of young children with special health care needs : maternal well-being and engagement in work

This thesis reports research focused on the well-being and employment experiences of mothers who have a child with special health care needs. Data are drawn from Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC). This is a public access database. The thesis uses the social ecological theory of Bronfenbrenner (1984) and the work of Zubrick et al. (2000) on human and social capital to inform the conceptual framework developed for the research. Four studies are reported. LSAC has a nationally representative sample of Australian children and their families. The study is tracking the development of 10,000 children, with data collected every two years, from 2004 to 2018. This thesis uses data from the Kindergarten Cohort of LSAC. The 4,983 children in the Kindergarten Cohort were aged 4 years at recruitment into the study in 2004. The analyses in this thesis use child and family data from Wave 1 (2004) and Wave 2 (2006) for a subsample of the children who are identified as having special health needs. This identification is based on a short screening questionnaire included in the Parent 1 Interview at each wave of the data collection. It is the children who are identified as having special health care needs which can be broadly defined as chronic health conditions or developmental difficulties. However, it is the well-being and employment experiences of the mothers of these children that are the primary focus in three of the four studies reported in this thesis.

Property law and practice in Queensland : being a commentary on the Property Law Act 1974

A Commentary on the Property Law Act 1974 Queensland

Industry branding : attracting talent to weaker profile industries

There is global competition for engineering talent with some industries struggling to attract quality candidates. The ‘brands’ of industries and organisations are important elements in attracting talent in a competitive environment. Using brand equity and signalling theory, this paper reports a quantitative study examining factors that attract graduating engineers and technicians to engineering careers in a weak brand profile industry. The survey measures graduating engineers’ preferences for career benefits and their perceptions of the rail industry, which has identified a significant skilled labour shortfall. Knowledge of young engineers’ preferences for certain benefits and segmenting preferences can inform branding and communications strategies. The findings have implications for all industries and organisations, especially those with a weaker brand profile and issues with attracting talent.