The use of speech and lip modalities for robust speaker verification under adverse conditions

Investigates the use of lip information, in conjunction with speech information, for robust speaker verification in the presence of background noise. We have previously shown (Int. Conf. on Acoustics, Speech and Signal Proc., vol. 6, pp. 3693-3696, May 1998) that features extracted from a speaker's moving lips hold speaker dependencies which are complementary with speech features. We demonstrate that the fusion of lip and speech information allows for a highly robust speaker verification system which outperforms either subsystem individually. We present a new technique for determining the weighting to be applied to each modality so as to optimize the performance of the fused system. Given a correct weighting, lip information is shown to be highly effective for reducing the false acceptance and false rejection error rates in the presence of background noise

Clinical factors and technological barriers as determinants for the intention to use wireless handheld technology in healthcare environment: an Indian case study

Abstract]: Traditional technology adoption models identified ‘ease of use’ and ‘usefulness’ as the dominating factors for technology adoption. However, recent studies in healthcare have established that these two factors are not always reliable on their own and other factors may influence technology adoption. To establish the identity of these additional factors, a mixed method approach was used and data were collected through interviews and a survey. The survey instrument was specifically developed for this study so that it is relevant to the Indian healthcare setting. We identified clinical management and technological barriers as the dominant factors influencing the wireless handheld technology adoption in the Indian healthcare environment. The results of this study showed that new technology models will benefit by considering the clinical influences of wireless handheld technology, in addition to known factors. The scope of this study is restricted to wireless handheld devices such as PDAs, smart phones, and handheld PCs Gururajan, Raj and Hafeez-Baig, Abdul and Gururajan, Vijaya

Can audio-visual speech recognition outperform acoustically enhanced speech recognition in automotive environment?

The use of visual features in the form of lip movements to improve the performance of acoustic speech recognition has been shown to work well, particularly in noisy acoustic conditions. However, whether this technique can outperform speech recognition incorporating well-known acoustic enhancement techniques, such as spectral subtraction, or multi-channel beamforming is not known. This is an important question to be answered especially in an automotive environment, for the design of an efficient human-vehicle computer interface. We perform a variety of speech recognition experiments on a challenging automotive speech dataset and results show that synchronous HMM-based audio-visual fusion can outperform traditional single as well as multi-channel acoustic speech enhancement techniques. We also show that further improvement in recognition performance can be obtained by fusing speech-enhanced audio with the visual modality, demonstrating the complementary nature of the two robust speech recognition approaches.

Conceptualisation of articular cartilage as a giant reverse micelle: A hypothetical mechanism for joint biocushioning and lubrication

Phospholipid (PL) molecules form the main structure of the membrane that prevents the direct contact of opposing articular cartilage layers. In this paper we conceptualise articular cartilage as a giant reverse micelle (GRM) in which the highly hydrated three-dimensional network of phospholipids is electrically charged and able to resist compressive forces during joint movement, and hence loading. Using this hypothetical base, we describe a hydrophilic-hydrophilic (HL-HL) biopair model of joint lubrication by contacting cartilages, whose mechanism is reliant on lamellar cushioning. To demonstrate the viability of our concept, the electrokinetic properties of the membranous layer on the articular surface were determined by measuring via microelectrophoresis, the adsorption of ions H, OH, Na and Cl on phospholipid membrane of liposomes, leading to the calculation of the effective surface charge density. The surface charge density was found to be -0.08 ± 0.002 cm-2 (mean ± S.D.) for phospholipid membranes, in 0.155 M NaCl solution and physiological pH. This value was approximately five times less than that measured in 0.01 M NaCl. The addition of synovial fluid (SF) to the 0.155 M NaCl solution reduced the surface charge density by 30% which was attributed to the binding of synovial fluid macromolecules to the phospholipid membrane. Our experiments show that particles charge and interact strongly with the polar core of RM. We demonstrate that particles can have strong electrostatic interactions when ions and macromolecules are solubilized by reverse micelle (RM). Since ions are solubilized by reverse micelle, the surface entropy influences the change in the charge density of the phospholipid membrane on cartilage surfaces. Reverse micelles stabilize ions maintaining equilibrium, their surface charges contribute to the stability of particles, while providing additional screening for electrostatic processes. © 2008 Elsevier Ireland Ltd. All rights reserved.

Political information choices in a media saturated environment : credibility or convenience?

This thesis examines the ways in which citizens find out about socio-political issues. The project set out to discover how audience characteristics such as scepticism towards the media, gratifications sought, need for cognition and political interest influence information selection. While most previous information choice studies have focused on how individuals select from a narrow range of media types, this thesis considered a much wider sweep of the information landscape. This approach was taken to obtain an understanding of information choices in a more authentic context - in everyday life, people are not simply restricted to one or two news sources. Rather, they may obtain political information from a vast range of information sources, including media sources (e.g. radio, television, newspapers) and sources from beyond the media (eg. interpersonal sources, public speaking events, social networking websites). Thus, the study included both media and non-news media information sources. Data collection for the project consisted of a written, postal survey. The survey was administered to a probability sample in the greater Brisbane region, which is the third largest city in Australia. Data was collected during March and April 2008, approximately four months after the 2007 Australian Federal Election. Hence, the study was conducted in a non-election context. 585 usable surveys were obtained. In addition to measuring the attitudinal characteristics listed above, respondents were surveyed as to which information sources (eg. television shows, radio stations, websites and festivals) they usually use to find out about socio-political issues. Multiple linear regression analysis was conducted to explore patterns of influence between the audience characteristics and information consumption patterns. The results of this analysis indicated an apparent difference between the way citizens use news media sources and the way they use information sources from beyond the news media. In essence, it appears that non-news media information sources are used very deliberately to seek socio-political information, while media sources are used in a less purposeful way. If media use in a non-election context, such as that of the present study, is not primarily concerned with deliberate information seeking, media use must instead have other primary purposes, with political information acquisition as either a secondary driver, or a by-product of that primary purpose. It appears, then, that political information consumption in a media-saturated society is more about routine ‘practices’ than it is about ‘information seeking’. The suggestion that media use is no longer primarily concerned with information seeking, but rather, is simply a behaviour which occurs within the broader set of everyday practices reflects Couldry’s (2004) media as practice paradigm. These findings highlight the need for more authentic and holistic contexts for media research. It is insufficient to consider information choices in isolation, or even from a wider range of information sources, such as that incorporated in the present study. Future media research must take greater account of the broader social contexts and practices in which media-oriented behaviours occur. The findings also call into question the previously assumed centrality of trust to information selection decisions. Citizens regularly use media they do not trust to find out about politics. If people are willing to use information sources they do not trust for democratically important topics such as politics, it is important that citizens possess the media literacy skills to effectively understand and evaluate the information they are presented with. Without the application of such media literacy skills, a steady diet of ‘fast food’ media may result in uninformed or misinformed voting decisions, which have implications for the effectiveness of democratic processes. This research has emphasized the need for further holistic and authentically contextualised media use research, to better understand how citizens use information sources to find out about important topics such as politics.

Modelling travelling waves in spatially constrained environment solutions

In this study, we consider how Fractional Differential Equations (FDEs) can be used to study the travelling wave phenomena in parabolic equations. As our method is conducted under intracellular environments that are highly crowded, it was discovered that there is a simple relationship between the travelling wave speed and obstacle density.

DEM test, visagraph eye movement recordings, and reading ability in children

Purpose. To determine how Developmental Eye Movement (DEM) test results relate to reading eye movement patterns recorded with the Visagraph in visually normal children, and whether DEM results and recorded eye movement patterns relate to standardized reading achievement scores. Methods. Fifty-nine school-age children (age = 9.7 ± 0.6 years) completed the DEM test and had eye movements recorded with the Visagraph III test while reading for comprehension. Monocular visual acuity in each eye and random dot stereoacuity were measured and standardized scores on independently administered reading comprehension tests [reading progress test (RPT)] were obtained. Results. Children with slower DEM horizontal and vertical adjusted times tended to have slower reading rates with the Visagraph (r = -0.547 and -0.414 respectively). Although a significant correlation was also found between the DEM ratio and Visagraph reading rate (r = -0.368), the strength of the relationship was less than that between DEM horizontal adjusted time and reading rate. DEM outcome scores were not significantly associated with RPT scores. When the relative contribution of reading ability (RPT) and DEM scores was accounted for in multivariate analysis, DEM outcomes were not significantly associated with Visagraph reading rate. RPT scores were associated with Visagraph outcomes of duration of fixations (r = -0.403) and calculated reading rate (r = 0.366) but not with DEM outcomes. Conclusions.DEM outcomes can identify children whose Visagraph recorded eye movement patterns show slow reading rates. However, when reading ability is accounted for, DEM outcomes are a poor predictor of reading rate. Visagraph outcomes of duration of fixation and reading rate relate to standardized reading achievement scores; however, DEM results do not. Copyright © 2011 American Academy of Optometry.

Arterial travel time estimation : revisiting the classical procedure

Travel time is an important network performance measure and it quantifies congestion in a manner easily understood by all transport users. In urban networks, travel time estimation is challenging due to number of reasons such as, fluctuations in traffic flow due to traffic signals, significant flow to/from mid link sinks/sources, etc. The classical analytical procedure utilizes cumulative plots at upstream and downstream locations for estimating travel time between the two locations. In this paper, we discuss about the issues and challenges with classical analytical procedure such as its vulnerability to non conservation of flow between the two locations. The complexity with respect to exit movement specific travel time is discussed. Recently, we have developed a methodology utilising classical procedure to estimate average travel time and its statistic on urban links (Bhaskar, Chung et al. 2010). Where, detector, signal and probe vehicle data is fused. In this paper we extend the methodology for route travel time estimation and test its performance using simulation. The originality is defining cumulative plots for each exit turning movement utilising historical database which is self updated after each estimation. The performance is also compared with a method solely based on probe (Probe-only). The performance of the proposed methodology has been found insensitive to different route flow, with average accuracy of more than 94% given a probe per estimation interval which is more than 5% increment in accuracy with respect to Probe-only method.

Scripting versus emergence : issues for game developers and players in game environment design

This paper defines and discusses two contrasting approaches to designing game environments. The first, referred to as scripting, requires developers to anticipate, hand-craft and script specific game objects, events and player interactions. The second, known as emergence, involves defining general, global rules that interact to give rise to emergent gameplay. Each of these approaches is defined, discussed and analyzed with respect to the considerations and affects for game developers and game players. Subsequently, various techniques for implementing these design approaches are identified and discussed. It is concluded that scripting and emergence are two extremes of the same continuum, neither of which are ideal for game development. Rather, there needs to be a compromise in which the boundaries of action (such as story and game objectives) can be hardcoded and non-scripted behavior (such as interactions and strategies) are able to emerge within these boundaries.

Enhancing employment services for people with severe mental illness: the challenge of the Australian service environment

Objectives:  Comparatively few people with severe mental illness are employed despite evidence that many people within this group wish to obtain, can obtain and sustain employment, and that employment can contribute to recovery. This investigation aimed to: (i) describe the current policy and service environment within which people with severe mental illness receive employment services; (ii) identify evidence-based practices that improve employment outcomes for people with severe mental illness; (iii) determine the extent to which the current Australian policy environment is consistent with the implementation of evidence-based employment services for people with severe mental illness; and (iv) identify methods and priorities for enhancing employment services for Australians with severe mental illness through implementation of evidence-based practices. Method:  Current Australian practices were identified, having reference to policy and legal documents, funding body requirements and anecdotal reports. Evidence-based employment services for people with severe mental illness were identified through examination of published reviews and the results of recent controlled trials. Results:  Current policy settings support the provision of employment services for people with severe mental illness separate from clinical services. Recent studies have identified integration of clinical and employment services as a major factor in the effectiveness of employment services. This is usually achieved through co-location of employment and mental health services. Conclusions:  Optimal evidence-based employment services are needed by Australians with severe mental illness. Providing optimal services is a challenge in the current policy environment. Service integration may be achieved through enhanced intersectoral links between employment and mental health service providers as well as by co-locating employment specialists within a mental health care setting.

The PSS : From Flat Maps to Layered Perspectives - the contribution of the Airport Metropolis Planning Support System (PSS) to sub-regional planning in the Brisbane Airport case environment

Conventional planning and decision making, with its sectoral and territorial emphasis and flat-map based processes are no longer adequate or appropriate for the increased complexity confronting airport/city interfaces. These crowed and often contested governance spaces demand a more iterative and relational planning and decision-making approach. Emergent GIS based planning and decision-making tools provide a mechanism which integrate and visually display an array of complex data, frameworks and scenarios/expectations, often in ‘real time’ computations. In so doing, these mechanisms provide a common ground for decision making and facilitate a more ‘joined-up’ approach to airport/city planning. This paper analyses the contribution of the Airport Metropolis Planning Support System (PSS) to sub-regional planning in the Brisbane Airport case environment.

Young children's understandings about "square" in 3D virtual reality microworlds

This paper reports an investigation of primary school children’s understandings about "square". 12 students participated in a small group teaching experiment session, where they were interviewed and guided to construct a square in a 3D virtual reality learning environment (VRLE). Main findings include mixed levels of "quasi" geometrical understandings, misconceptions about length and angles, and ambiguous uses of geometrical language for location, direction, and movement. These have implications for future teaching and learning about 2D shapes with particular reference to VRLE.

A longitudinal study of corporate earnings guidance in Australia’s continuous disclosure environment

Since the introduction of a statutory‐backed continuous disclosure regime (CDR) in 1994, regulatory reforms have significantly increased litigation risk in Australia for failure to disclose material information or for false and misleading disclosure. However, there is almost no empirical research on the impact of the reforms on corporate disclosure behaviour. Motivated by the absence of research and using management earnings forecasts (MEFs) as a disclosure proxy, this study examines (1) why managers issue earnings forecasts, (2) what firm‐specific factors influence MEF characteristics, and (3) how MEF behaviour changes as litigation risk increases. Based on theories in information economics, a theoretical framework for MEF behaviour is formulated which includes antecedent influencing factors related to firms‟ internal and external environments. Applying this framework, hypotheses are developed and tested using multivariate models and a large sample of hand-collected MEFs (7,213) issued by top 500 ASX-listed companies over the 1994 to 2008 period. The results reveal strong support for the hypotheses. First, MEFs are issued to reduce information asymmetry, litigation risk and signal superior performance. Second, firms with better financial performance, smaller earnings changes, and lower operating uncertainty provide better quality MEFs. Third, forecast frequency and quality (accuracy, timeliness and precision) noticeably improve as litigation risk increases. However, managers appear to be still reluctant to disclose earnings forecasts when there are large earnings changes, and an asymmetric treatment of news type continues to prevail (a good news bias). Thus, the findings generally provide support for the effectiveness of the CDR regulatory reforms in improving disclosure behaviour and will be valuable to market participants and corporate regulators in understanding the implications of management forecasting decisions and areas for further improvement.

Facilitating student self-direction in a blended learning environment

Business postgraduate education is rapidly adopting virtual learning environments to facilitate the needs of a time-poor stakeholder community, where part-time students find it difficult to attend face-to-face classes. Creating engaged, flexible learning opportunities in the virtual world is therefore the current challenge for many business academics. However, in the blended learning environment there is also the added pressure of encouraging these students to develop soft managerial or generic skills such as self-reflection. The current paper provides an overview of an action-research activity exploring the experiences of students who were required to acquire the skills of self-reflection within a blended learning unit dominated by on-line learning delivery. We present the responses of students and the changes made to our teaching and learning activities to improve the facilitation of both our face-to-face delivery as well as the on-line learning environment.