Sequential decision fusion of multibiometrics applied to text-dependent speaker verification for controlled errors

Reliability of the performance of biometric identity verification systems remains a significant challenge. Individual biometric samples of the same person (identity class) are not identical at each presentation and performance degradation arises from intra-class variability and inter-class similarity. These limitations lead to false accepts and false rejects that are dependent. It is therefore difficult to reduce the rate of one type of error without increasing the other. The focus of this dissertation is to investigate a method based on classifier fusion techniques to better control the trade-off between the verification errors using text-dependent speaker verification as the test platform. A sequential classifier fusion architecture that integrates multi-instance and multisample fusion schemes is proposed. This fusion method enables a controlled trade-off between false alarms and false rejects. For statistically independent classifier decisions, analytical expressions for each type of verification error are derived using base classifier performances. As this assumption may not be always valid, these expressions are modified to incorporate the correlation between statistically dependent decisions from clients and impostors. The architecture is empirically evaluated by applying the proposed architecture for text dependent speaker verification using the Hidden Markov Model based digit dependent speaker models in each stage with multiple attempts for each digit utterance. The trade-off between the verification errors is controlled using the parameters, number of decision stages (instances) and the number of attempts at each decision stage (samples), fine-tuned on evaluation/tune set. The statistical validation of the derived expressions for error estimates is evaluated on test data. The performance of the sequential method is further demonstrated to depend on the order of the combination of digits (instances) and the nature of repetitive attempts (samples). The false rejection and false acceptance rates for proposed fusion are estimated using the base classifier performances, the variance in correlation between classifier decisions and the sequence of classifiers with favourable dependence selected using the 'Sequential Error Ratio' criteria. The error rates are better estimated by incorporating user-dependent (such as speaker-dependent thresholds and speaker-specific digit combinations) and class-dependent (such as clientimpostor dependent favourable combinations and class-error based threshold estimation) information. The proposed architecture is desirable in most of the speaker verification applications such as remote authentication, telephone and internet shopping applications. The tuning of parameters - the number of instances and samples - serve both the security and user convenience requirements of speaker-specific verification. The architecture investigated here is applicable to verification using other biometric modalities such as handwriting, fingerprints and key strokes.

The health information practices of people living with chronic health conditions: Implications for health literacy

The reduction of the health literacy concept to a functional relationship with text, does not acknowledge the range of information sources that people draw from in order to make informed decision about their health and treatment. Drawing from two studies that explored how people with two different but complex and life-threatening chronic health conditions, chronic kidney disease and HIV, a socio-cultural understanding of the practise of health literacy is described. Health information is experienced by patients as a chronic health condition landscape, and develops from three information sources; namely epistemic, social and corporeal sources. Participants in both studies used activities that involved orienting, sharing and creating information to map this landscape which was used to inform their decision-making. These findings challenge the traditional conceptions of health literacy and suggest an approach that views the landscape of chronic illness as being socially, physically and contextually constructed. This approach necessitates a recasting of health literacy away from a sole interest in skills and towards understanding how information practices facilitate people becoming health literate.

Mapping local solutions to entrenched transport problems: Key lessons regarding the use of geographical information technologies in community mapping with disadvantaged communities

There is an increasing interest in the use of information technology as a participatory planning tool, particularly the use of geographical information technologies to support collaborative activities such as community mapping. However, despite their promise, the introduction of such technologies does not necessarily promote better participation nor improve collaboration. In part this can be attributed to a tendency for planners to focus on the technical considerations associated with these technologies at the expense of broader participation considerations. In this paper we draw on the experiences of a community mapping project with disadvantaged communities in suburban Australia to highlight the importance of selecting tools and techniques which support and enhance participatory planning. This community mapping project, designed to identify and document community-generated transport issues and solutions, had originally intended to use cadastral maps extracted from the government’s digital cadastral database as the foundation for its community mapping approach. It was quickly discovered that the local residents found the cadastral maps confusing as the maps lacked sufficient detail to orient them to their suburb (the study area). In response to these concerns and consistent with the project’s participatory framework, a conceptual base map based on resident’s views of landmarks of local importance was developed to support the community mapping process. Based on this community mapping experience we outline four key lessons learned regarding the process of community mapping and the place of geographical information technologies within this process.

On effective accounting information systems in a dynamic business environment : the role of complementing capabilities

The global business environment is witnessing tough times, and this situation has significant implications on how organizations manage their processes and resources. Accounting information system (AIS) plays a critical role in this situation to ensure appropriate processing of financial transactions and availability to relevant information for decision-making. We suggest the need for a dynamic AIS environment for today’s turbulent business environment. This environment is possible with a dynamic AIS, complementary business intelligence systems, and technical human capability. Data collected through a field survey suggests that the dynamic AIS environment contributes to an organization’s accounting functions of processing transactions, providing information for decision making, and ensuring an appropriate control environment. These accounting processes contribute to the firm-level performance of the organization. From these outcomes, one can infer that a dynamic AIS environment contributes to organizational performance in today’s challenging business environment.

Cone signals and activity in myopia and emmetropia

Myopia (short-sightedness) is a common ocular disorder of children and young adults. Studies primarily using animal models have shown that the retina controls eye growth and the outer retina is likely to have a key role. One theory is that the proportion of L (long-wavelength-sensitive) and M (medium-wavelength-sensitive) cones is related to myopia development; with a high L/M cone ratio predisposing individuals to myopia. However, not all dichromats (persons with red-green colour vision deficiency) with extreme L/M cone ratios have high refractive errors. We predict that the L/M cone ratio will vary in individuals with normal trichromatic colour vision but not show a systematic difference simply due to refractive error. The aim of this study was to determine if L/M cone ratios in the central 30° are different between myopic and emmetropic young, colour normal adults. Information about L/M cone ratios was determined using the multifocal visual evoked potential (mfVEP). The mfVEP can be used to measure the response of visual cortex to different visual stimuli. The visual stimuli were generated and measurements performed using the Visual Evoked Response Imaging System (VERIS 5.1). The mfVEP was measured when the L and M cone systems were separately stimulated using the method of silent substitution. The method of silent substitution alters the output of three primary lights, each with physically different spectral distributions to control the excitation of one or more photoreceptor classes without changing the excitation of the unmodulated photoreceptor classes. The stimulus was a dartboard array subtending 30° horizontally and 30° vertically on a calibrated LCD screen. The m-sequence of the stimulus was 215-1. The N1-P1 amplitude ratio of the mfVEP was used to estimate the L/M cone ratio. Data were collected for 30 young adults (22 to 33 years of age), consisting of 10 emmetropes (+0.3±0.4 D) and 20 myopes (–3.4±1.7 D). The stimulus and analysis techniques were confirmed using responses of two dichromats. For the entire participant group, the estimated central L/M cone ratios ranged from 0.56 to 1.80 in the central 3°-13° diameter ring and from 0.94 to 1.91 in the more peripheral 13°-30° diameter ring. Within 3°-13°, the mean L/M cone ratio of the emmetropic group was 1.20±0.33 and the mean was similar, 1.20±0.26, for the myopic group. For the 13°-30° ring, the mean L/M cone ratio of the emmetropic group was 1.48±0.27 and it was slightly lower in the myopic group, 1.30±0.27. Independent-samples t-test indicated no significant difference between the L/M cone ratios of the emmetropic and myopic group for either the central 3°-13° ring (p=0.986) or the more peripheral 13°-30° ring (p=0.108). The similar distributions of estimated L/M cone ratios in the sample of emmetropes and myopes indicates that there is likely to be no association between the L/M cone ratio and refractive error in humans.

Speaker attribution of Australian broadcast news data

Speaker attribution is the task of annotating a spoken audio archive based on speaker identities. This can be achieved using speaker diarization and speaker linking. In our previous work, we proposed an efficient attribution system, using complete-linkage clustering, for conducting attribution of large sets of two-speaker telephone data. In this paper, we build on our proposed approach to achieve a robust system, applicable to multiple recording domains. To do this, we first extend the diarization module of our system to accommodate multi-speaker (>2) recordings. We achieve this through using a robust cross-likelihood ratio (CLR) threshold stopping criterion for clustering, as opposed to the original stopping criterion of two speakers used for telephone data. We evaluate this baseline diarization module across a dataset of Australian broadcast news recordings, showing a significant lack of diarization accuracy without previous knowledge of the true number of speakers within a recording. We thus propose applying an additional pass of complete-linkage clustering to the diarization module, demonstrating an absolute improvement of 20% in diarization error rate (DER). We then evaluate our proposed multi-domain attribution system across the broadcast news data, demonstrating achievable attribution error rates (AER) as low as 17%.

Information and Learning Experiences in the Cube: Vision, Implementation and Interaction

Executive Summary This project has commenced an exploration of learning and information experiences in the QUT Cube. Understanding learning in this environment has the potential to inform current implementations and future project development. In this report, we present early findings from the first phase of an investigation into what makes learning possible in the context of a giant interactive multi-media display such as the QUT Cube, which is an award-winning configuration that hosts several projects.

Taming the terabytes : a human-centered approach to surviving the information deluge

A fear of imminent information overload predates the World Wide Web by decades. Yet, that fear has never abated. Worse, as the World Wide Web today takes the lion’s share of the information we deal with, both in amount and in time spent gathering it, the situation has only become more precarious. This chapter analyses new issues in information overload that have emerged with the advent of the Web, which emphasizes written communication, defined in this context as the exchange of ideas expressed informally, often casually, as in verbal language. The chapter focuses on three ways to mitigate these issues. First, it helps us, the users, to be more specific in what we ask for. Second, it helps us amend our request when we don't get what we think we asked for. And third, since only we, the human users, can judge whether the information received is what we want, it makes retrieval techniques more effective by basing them on how humans structure information. This chapter reports on extensive experiments we conducted in all three areas. First, to let users be more specific in describing an information need, they were allowed to express themselves in an unrestricted conversational style. This way, they could convey their information need as if they were talking to a fellow human instead of using the two or three words typically supplied to a search engine. Second, users were provided with effective ways to zoom in on the desired information once potentially relevant information became available. Third, a variety of experiments focused on the search engine itself as the mediator between request and delivery of information. All examples that are explained in detail have actually been implemented. The results of our experiments demonstrate how a human-centered approach can reduce information overload in an area that grows in importance with each day that passes. By actually having built these applications, I present an operational, not just aspirational approach.

Sensemaking and sustainable practicing: Functional affordances of information systems in green transformations

This paper explores how a world-wide operating software solutions provider implemented environmentally sustainable business practices in response to emerging environmental concerns. Through an interpretive case study, we develop a theoretical framework that identifies four important functional affordances originating in information systems, which are required in environmental sustainability transformations as they create an actionable context in which (1) organizations can engage in a sensemaking process related to understanding emerging environmental requirements, and (2) individuals can implement environmentally sustainable work practices. Through our work, we provide several contributions, including a better understanding of IS-enabled organizational change and the types of functional affordances of information systems that are required in sustainability transformations. We describe implications relating to (1) how information systems can contribute to the creation of environmentally sustainable organizations, (2) the design of information systems to create required functional affordances, (3) the management of sustainability transformations, and (4) the further development of the concept of functional affordances in IS research.

Protocol for a randomised blocked design study using telephone and text-messaging to support cardiac patients with diabetes : a cross cultural international collaborative project

Background The prevalence of type 2 diabetes is rising internationally. Patients with diabetes have a higher risk of cardiovascular events accounting for substantial premature morbidity and mortality, and health care expenditure. Given healthcare workforce limitations, there is a need to improve interventions that promote positive self-management behaviours that enable patients to manage their chronic conditions effectively, across different cultural contexts. Previous studies have evaluated the feasibility of including telephone and Short Message Service (SMS) follow up in chronic disease self-management programs, but only for single diseases or in one specific population. Therefore, the aim of this study is to evaluate the feasibility and short-term efficacy of incorporating telephone and text messaging to support the care of patients with diabetes and cardiac disease, in Australia and in Taiwan. Methods/design A randomised controlled trial design will be used to evaluate a self-management program for people with diabetes and cardiac disease that incorporates the use of simple remote-access communication technologies. A sample size of 180 participants from Australia and Taiwan will be recruited and randomised in a one-to-one ratio to receive either the intervention in addition to usual care (intervention) or usual care alone (control). The intervention will consist of in-hospital education as well as follow up utilising personal telephone calls and SMS reminders. Primary short term outcomes of interest include self-care behaviours and self-efficacy assessed at baseline and four weeks. Discussion If the results of this investigation substantiate the feasibility and efficacy of the telephone and SMS intervention for promoting self management among patients with diabetes and cardiac disease in Australia and Taiwan, it will support the external validity of the intervention. It is anticipated that empirical data from this investigation will provide valuable information to inform future international collaborations, while providing a platform for further enhancements of the program, which has potential to benefit patients internationally.

Health Information Literacy and the Experience of 65 to 79 Year Old Australians

Information literacy is presented here from a relational perspective, as people’s experience of using information to learn in a particular context. A detailed practical example of such a context is provided, in the health information literacy experience of 65–79 year old Australians. A phenomenographic investigation found five qualitatively distinct ways of experiencing health information literacy: Absorbing (intuitive reception), Targeting (a planned process), Journeying (a personal quest), Liberating (equipping for independence) and Collaborating (interacting in community). These five ways of experiencing indicated expanding awareness of context (degree of orientation towards their environment), source (breadth of esteemed information), beneficiary (the scope of people who gain) and agency (amount of activity), across HIL core aspects of information, learning and health. These results illustrate the potential contribution of relational information literacy to information science.

Understanding and measuring information security culture in developing countries : case of Saudi Arabia

The purpose of the current study was to develop a measurement of information security culture in developing countries such as Saudi Arabia. In order to achieve this goal, the study commenced with a comprehensive review of the literature, the outcome being the development of a conceptual model as a reference base. The literature review revealed a lack of academic and professional research into information security culture in developing countries and more specifically in Saudi Arabia. Given the increasing importance and significant investment developing countries are making in information technology, there is a clear need to investigate information security culture from developing countries perspective such as Saudi Arabia. Furthermore, our analysis indicated a lack of clear conceptualization and distinction between factors that constitute information security culture and factors that influence information security culture. Our research aims to fill this gap by developing and validating a measurement model of information security culture, as well as developing initial understanding of factors that influence security culture. A sequential mixed method consisting of a qualitative phase to explore the conceptualisation of information security culture, and a quantitative phase to validate the model is adopted for this research. In the qualitative phase, eight interviews with information security experts in eight different Saudi organisations were conducted, revealing that security culture can be constituted as reflection of security awareness, security compliance and security ownership. Additionally, the qualitative interviews have revealed that factors that influence security culture are top management involvement, policy enforcement, policy maintenance, training and ethical conduct policies. These factors were confirmed by the literature review as being critical and important for the creation of security culture and formed the basis for our initial information security culture model, which was operationalised and tested in different Saudi Arabian organisations. Using data from two hundred and fifty-four valid responses, we demonstrated the validity and reliability of the information security culture model through Exploratory Factor Analysis (EFA), followed by Confirmatory Factor Analysis (CFA.) In addition, using Structural Equation Modelling (SEM) we were further able to demonstrate the validity of the model in a nomological net, as well as provide some preliminary findings on the factors that influence information security culture. The current study contributes to the existing body of knowledge in two major ways: firstly, it develops an information security culture measurement model; secondly, it presents empirical evidence for the nomological validity for the security culture measurement model and discovery of factors that influence information security culture. The current study also indicates possible future related research needs.

A social matching system : using implicit and explicit information for personalized recommendation in online dating service

Online dating websites enable a specific form of social networking and their efficiency can be increased by supporting proactive recommendations based on participants' preferences with the use of data mining. This research develops two-way recommendation methods for people-to-people recommendation for large online social networks such as online dating networks. This research discovers the characteristics of the online dating networks and utilises these characteristics in developing efficient people-to-people recommendation methods. Methods developed support improved recommendation accuracy, can handle data sparsity that often comes with large data sets and are scalable for handling online networks with a large number of users.

Hybrid antibacterial fabrics with extremely high aspect ratio Ag/AgTCNQ nanowires

This study reports the synthesis of extremely high aspect ratios (>3000) organic semiconductor nanowires of Ag–tetracyanoquinodimethane (AgTCNQ) on the surface of a flexible Ag fabric for the first time. These one-dimensional (1D) hybrid Ag/AgTCNQ nanostructures are attained by a facile, solution-based spontaneous reaction involving immersion of Ag fabrics in an acetonitrile solution of TCNQ. Further, it is discovered that these AgTCNQ nanowires show outstanding antibacterial performance against both Gram negative and Gram positive bacteria, which outperforms that of pristine Ag. The outcomes of this study also reflect upon a fundamentally important aspect that the antimicrobial performance of Ag-based nanomaterials may not necessarily be solely due to the amount of Ag+ ions leached from these nanomaterials, but that the nanomaterial itself may also play a direct role in the antimicrobial action. Notably, the applications of metal-organic semiconducting charge transfer complexes of metal-7,7,8,8-tetracyanoquinodimethane (TCNQ) have been predominantly restricted to electronic applications, except from our recent reports on their (photo)catalytic potential and the current case on antimicrobial prospects. This report on growth of these metal-TCNQ complexes on a fabric not only widens the window of these interesting materials for new biological applications, it also opens the possibilities for developing large-area flexible electronic devices by growing a range of metal-organic semiconducting materials directly on a fabric surface.

Conference Keynote: Information literacy research and practice: An experiential perspective

In this paper I will explore some experience-based perspectives on information literacy research and practice. The research based understanding of what information literacy looks like to those experiencing it, is very different from the standard interpretations of information literacy as involving largely text based information searching, interpretation, evaluation and use. It also involves particular understandings of the interrelation between information and learning experiences. In following this thread of the history of information literacy I will reflect on aspects of the past, present and future of information literacy research. In each of these areas I explore experiential, especially phenomenographic approaches to information literacy and information literacy education, to reveal the unfolding understanding of people’s experience of information literacy stemming from this orientation. In addressing the past I will look in particular at the contribution of the seven faces of information literacy and some lessons learned from attending to variation in experience. I will explore important directions and insights that this history may help us to retain; including the value of understanding peoples’ information literacy experience. In addressing the present, I will introduce more recent work that adopts the key ideas of informed learning by attending to both information and learning experiences in specific contexts. I will look at some contemporary directions and key issues, including the reinvention of the phenomenographic, or relational approach to information literacy as informed learning or using information to learn. I will also provide some examples of the contribution of experiential approaches to information literacy research and practice. The evolution and development of the phenomenographic approach to information literacy, and the growing attention to a dual focus on information and learning experiences in this approach will be highlighted. Finally, in addressing the future I will return to advocacy, the recognition and pursuit of the transforming and empowering heart of information literacy; and suggest that for information literacy research, including the experiential, a turn towards the emancipatory has much to offer.