Digital Commons Network^™

Converging Voice, Video And Data In Wlan With Qos Support, Hushairi Zen, Daryoush Habibi, Justin Wyatt, Iftekhar Ahmad

Research outputs pre 2011

Providing quality of service (QoS) for converging traffic in wireless local area network (WLAN) is still a major issue for the researchers and industries. Due to the limited bandwidth and exposure to unpredictable interferences in a wireless environment, efficient management and optimization of the access protocols are essential to provide acceptable QoS for real-time traffic and fairness to best-effort traffic. In this paper, we investigate the throughput and delay performance of the legacy IEEE 802.11 and the 802.11e when carrying converging data in WLAN. We evaluate our recently proposed protocol known as wireless token network protocol (WTN) and show that …

Realized Volatility Uncertainty, David E. Allen, Michael Mcaleer, Marcel Scharth

Research outputs pre 2011

The presence of high and time-varying volatility of volatility and leverage effects bring additional uncertainty in the tails of the distribution of asset returns, even though returns standardized by (ex-post) quadratic variation measures are nearly gaussian. We argue that in this setting modeling shocks to volatility is more relevant for applications than extracting more precise predictions of the variable, as point forecasts differences are swamped by the size of the volatility of volatility and rendered less informative by the nongaussianity in the ex-ante distribution of returns. Using S&P 500 data, we document that this volatility of volatility is subject to …

13c And 15n Translocation Within And Among Shoots In Two Posidonia Species From Western Australia, Patricia Prado, Catherine Jane Collier, Paul Lavery

Research outputs pre 2011

Translocation of 13C and 15N was investigated at the spatial scales of within-shoot (i.e. the seagrass clonal unit including leaves and associated vertical rhizome) and among-shoots in a mixed meadow of Posidonia sinuosa and P. australis. Incubation with 13C and 15N was conducted in either the oldest leaf of a shoot (i.e. within-shoot scale) or in the first shoot on the 4th or 5th branch of the main axis (i.e. among-shoots scale) and collected several times within a 1 mo period. We tested the following hypotheses: (1) developmental features in P. australis such as thicker and more open vascular system, …

Bots Trained To Play Like A Human Are More Fun, Bhuman Soni, Philip Hingston

Research outputs pre 2011

Computational intelligence methods are well-suited for use in computer controlled opponents for video games. In many other applications of these methods, the aim is to simulate near-optimal intelligent behaviour. But in video games, the aim is to provide interesting opponents for human players, not optimal ones. In this study, we trained neural network-based computer controlled opponents to play like a human in a popular first-person shooter. We then had gamers play-test these opponents as well as a hand-coded opponent, and surveyed them to find out which opponents they enjoyed more. Our results show that the neural network-based opponents were clearly …

Cultural Factors Affecting Smoking Intentions In Sri Lankan Immigrant Adolescents: An Exploratory Study, Raguragavan Ganeshasundaram, Nadine Henley

Research outputs pre 2011

This paper reports a small exploratory investigation into smoking intentions amongst Sri Lankan immigrant adolescents living in Perth, Western Australia. Four focus group discussions were conducted to explore how cultural values are expressed in this group's beliefs and attitudes towards smoking and non-smoking and how these values may influence their smoking-related behaviour. Females and males attached similar negative values to smoking per se. However, generally, males saw peers' smoking as a way to be cool and popular while females saw peers' smoking as a way to solve stress and other personal problems. Males had strong positive associations with their favourite …

Fast Evaluation Of The Square Root And Other Nonlinear Functions In Fpga, Stefan Lachowicz, Hans-Joerg Pfleiderer

Research outputs pre 2011

The paper presents a novel method of evaluating the square root function in FPGA. The method uses a linear approximation subsystem with a reduced size of a look-up table. The reduction in the size of the lookup table is twofold. Firstly, a simple linear approximation subsystem uses the lookup table only for the node points. Secondly, a concept of a variable step look-up table is introduced, where the node points are not uniformly spaced, but the spacing is determined by how close to the linear function the approximated function is. The proposed method of evaluating nonlinear function and specifically the …

Research Criteria For The Diagnosis Of Alzheimer's Disease: Genetic Risk Factors, Blood Biomarkers And Olfactory Dysfunction, Jonathan Foster, Hamid Sohrabi, Giuseppe Verdile, Ralph Martins

Research outputs pre 2011

No abstract provided.

Supporting Component Selection With A Suite Of Classifiers, Valerie Maxville, Chiou Peng Lam, J Armarego

Research outputs pre 2011

Software selection involves the assimilation of information and results for each candidate to enable a comparison for decisions to be made. The processes and tools developed assist with software selection to enhance quality, documentation and repeatability. The CdCE process aims to retain and document the information used in selection to assist decisions and to document them for reference as the system evolves. This paper describes the CdCE process and our approach to assist the shortlisting of candidates through a suite of classifiers. The application of the suite is illustrated using a selection and evaluation case study. Applying this approach helps …

Dancing Between Diversity And Consistency: Refining Assessment In Postgraduate Degrees In Dance, Maggie Phillips, Cheryl Stock, Kim Vincs

Research outputs pre 2011

Guidelines for best practice in Australian Doctoral and Masters by Research Examination, enc;ompassing the two primary modes of investigation, written and multi-modal theses, their distinctiveness and their potential interplay.

You've Got Mail: Accountability And End User Attitudes To Email Management, Mark Brogan, Susan Vreugdenburg

Research outputs pre 2011

In a pioneering ethnographic study of end user responses to the problem of ‘information overload’ Whittaker and Sidner (1996) found that the design of systems primarily as methods of asynchronous communication, posed significant information management problems for users. In another contemporaneous study, David Bearman (1993) extended understanding of the implications of end user email management behavior by identifying significant accountability implications for organizations arising from the use of email. Recent case studies in the United States and Australia (Leopold, 2008; Raleigh Chronicle, 2008; Strutt, and Taylor, 2007) have once again focused attention on the accountability consequences for Government of email …

Photography After The Incidents: We're Not Afraid, Panizza Allmark

Research outputs pre 2011

This article will look at the use of personal photographs that attempt to convey a sense of social activism as a reaction against global terrorism. Moreover, I argue that the photographs uploaded to the site “We’re Not Afraid”, which began after the London bombings in 2005, presents a forum to promote the pleasures of western cultural values as a defence against the anxiety of terror. What is compelling are the ways in which the Website promotes, seemingly, everyday modalities through what may be deemed as the domestic snapshot. Nevertheless, the aura from the context of these images operates to arouse …

Estimating The Dynamics Of Mutual Fund Alphas And Betas, Harry Mamaysky, Matthew Spiegel, Hong Zhang

Research Collection Lee Kong Chian School Of Business

This article develops a Kalman filter model to track dynamic mutual fund factor loadings. It then uses the estimates to analyze whether managers with market-timing ability can be identified ex ante. The primary findings are as follows: (i) Ordinary least squares (OLS) timing models produce false positives (nonzero alphas) at too high a rate with either daily or monthly data. In contrast, the Kalman filter model produces them at approximately the correct rate with monthly data; (ii) In monthly data, though the OLS models fail to detect any timing among fund managers, the Kalman filter does; (iii) The alpha and …

Less Than Equal: Secularism, Religious Pluralism And Privilege, Anne Aly, Lelia Rosalind Green

Research outputs pre 2011

In its preamble, The Western Australian Charter of Multiculturalism (WA) commits the state to becoming: “A society in which respect for mutual difference is accompanied by equality of opportunity within a framework of democratic citizenship”. One of the principles of multiculturalism, as enunciated in the Charter, is “equality of opportunity for all members of society to achieve their full potential in a free and democratic society where every individual is equal before and under the law”. An important element of this principle is the “equality of opportunity ... to achieve ... full potential”. The implication here is that those who …

Optimized Wlan Mac Protocol For Multimedia Applications, Hushairi Zen, Daryoush Habibi, Alexander Rassau, Iftekhar Ahmad

Research outputs pre 2011

In this paper we propose an optimized WLAN MAC protocol for multimedia applications. The proposed MAC protocol consist of 3 main optimizing architectures, traffic segregation, specific service interval (SI) for voice and video traffic and smaller contention window (CW). Traffic segregation segregates real-time traffic from best-effort traffic while specific service interval provides voice and video traffic with the SI based on its mean arrival rate. In the contention time frame, the CW is made smaller to reduce delay and increase throughput. Ns2 is used as a simulating tool to compare the results of our proposed protocol with the legacy 802.11 …

Diversity: A Longitudinal Study Of How Student Diversity Relates To Resilience And Successful Progression In A New Generation University, Adrianne Kinnear, Mary Boyce, Heather Sparrow, Sharon Middleton, Marguerite Cullity

Research outputs pre 2011

This project used the voices of diverse cohorts of students to describe their learning journeys as they progressed through the later years of their degree and into the workforce. The project combined quantitative data from a large student sample with qualitative data from a series of case study narratives to document the students’ perceptions about their learning experiences, the factors underpinning progression in their studies and their transition into the workplace. The project has attempted to answer the question: does diversity matter? Do students of different diversities progress differently, and are there differences in the factors enhancing progression and developing …

Engaging Academically At Risk Primary School Students In An Ict Mediated After-School Program, Lee Yong Tay, Cher Ping Lim

Research outputs pre 2011

This case study documents how a group of 14 academically at risk Primary 5 students (11 year olds) were engaged in academic related tasks in an after school program mediated by a 3-D Multi-User Virtual Environment (MUVE). Although there was no significant difference in the students' academic performance, they were found to be more engaged in the learning tasks and had acquired a range of information and communication technology (ICT) skills. At the start of the program students attended irregularly, but this improved gradually over the weeks, and other Primary 5 students were attracted to enrol in the program. …

Tunable True-Time Delay Unit Based On Opto-Vlsi Processing, Feng Xiao, Budi Juswardy, Kamal Alameh

Research outputs pre 2011

A novel tunable true-time delay unit is proposed and demonstrated. The unit is based on the use of an Opto-VLSI processor that dynamically selects a single waveband or multiple wavebands from an RF-modulated broadband optical signal and routes them to a high-dispersion fiber for arbitrary time delay synthesis. Experimental results demonstrate continuously tunable time delay of up to 4 ns.

The Osi Network Management Model - Capacity And Performance Management, Chompu Nuangjamnong, Stanislaw P. Maj, David Veal

Research outputs pre 2011

With the rapid growth of large enterprise networks, capacity and performance management issues are becoming increasingly important to both business organizations and the telecommunication industry. Capacity and performance management techniques and methods provide guidance on how to plan, justify and manage network resources. Inappropriate planning for capacity and performance may lead to wasted resources resulting in unnecessary cost, or lack of resources resulting in poor network performance or even the unavailability of IT services. Moreover, it is not uncommon for networks to be equipped with devices from different vendors which potentially add to complexity. Resource management may be assisted by …

Creating A Web-Based Knowledge-Building Team: Design Of Tasks, Scaffolds And Social Affordances, Catherine Mcloughlin, Joseph Luca

Research outputs pre 2011

In a blended learning environment, where students undertake professional skills development in the workplace, a flexible environment is designed in order to support problem solving in project management. The design of the environment, informed by socio-cultural theory, was intended to support knowledge building among students, and in particular to support exchange of ideas, peer review and commentary on solutions presented to problems, and a reflective space for exchange of ideas. The online environment incorporates a number of functional affordances that scaffold knowledge exchange, collaborative tasks and peer commentary. The design features of the online site are described and a proposed …

Doped Iron Garnet Materials For Magnetic Photonic Crystals, Mikhail Vasiliev, Kamal Alameh, Viatcheslav Kotov

Research outputs pre 2011

We have established a set of technologies for the deposition and annealing of magneto-optic garnets for use in photonic crystals. Devices for sensing magnetic fields and polarisation control using reconfigurable photonic crystals are being developed.

The Use Of Neural Networks In The Prediction Of The Stock Exchange Of Thailand (Set) Index, Suchira Chaigusin, Chaiyaporn Chirathamjaree, Judith Clayden

Research outputs pre 2011

Prediction of stock prices is an issue of interest to financial markets. Many prediction techniques have been reported in stock forecasting. Neural networks are viewed as one of the more suitable techniques. In this study, an experiment on the forecasting of the Stock Exchange of Thailand (SET) was conducted by using feedforward backpropagation neural networks. In the experiment, many combinations of parameters were investigated to identify the right set of parameters for the neural network models in the forecasting of SET. Several global and local factors influencing the Thai stock market were used in developing the models, including the Dow …

Magnetic Field Sensors And Visualizers Using Magnetic Photonic Crystals, Mikhail Vasiliev, Kamal Alameh, Viatcheslav Kotov

Research outputs pre 2011

Magneto-optical imaging is widely used to observe the domain patterns in magnetic materials, visualize defects in ferromagnetic objects, and measure the spatial distribution of stray magnetic fields. Optimized 1D magneto-photonic crystals enable a significant increase in the sensitivity of magneto-optical sensors. The properties of such devices based on the optimized reflection (doubled Faraday rotation) mode and the use of 1D magnetic photonic crystals as sensors are discussed. Experimental results of the fabrication and characterization of ferrite-garnet layers possessing uniaxial magnetic anisotropy are shown, and an optimized film structure suitable for magneto-optical imaging is proposed.

Opto-Vlsi-Based Reconfigurable Microwave Photonic Transversal Filter With Positive And Negative Coefficients, Feng Xiao, Budi Juswardy, Kamal Alameh

Research outputs pre 2011

A novel reconfigurable microwave photonic filter structure with positive and negative coefficients is proposed and demonstrated. The filter structure comprises two arrayed waveguide gratings, a custom-made fiber array, high-dispersion fibres, and a reconfigurable opto-VLSI processor. Positive and negative filter weights can flexibly be synthesised to realise arbitrary transfer functions. Experimental results are presented, which demonstrate the principle of the proposed filter structure.

Pax7 Is Requisite For Maintenance Of A Subpopulation Of Superior Collicular Neurons And Shows A Diverging Expression Pattern To Pax3 During Superioir Collicular Development, Jennifer Thompson, Andreas Zembrzycki, Ahmed Mansouri, Melanie Ziman

Research outputs pre 2011

Pax7 encodes a transcription factor well-established as an important determinant of mesencephalic identity and superior collicular development. Pax7 mutant mice, however, present with no obvious morphological impairments to the superior colliculus. This finding is paradoxical and has been attributed to functional redundancy afforded by its paralogue Pax3. Here we utilise Pax7 mutant mice to investigate the precise role of this important developmental regulator during superior collicular development and neuronal specification/differentiation. We also assess its spatiotemporal relationship with Pax3 during embryonic development. Analysis of the superior colliculus of Pax7 mutant and wildtype mice at a variety of developmental timepoints revealed that …

Falls, Depression And Antidepressants In Later Life: A Large Primary Care Appraisal, Ngaire Kerse, Leon Flicker, Jon J. Pfaff, Brian Draper, Nicola T. Lautenschlager, Moira Sim, John Snowdon, Osvaldo P Almeida

Research outputs pre 2011

Background: Depression and falls are common and co-exist for older people. Safe management of each of these conditions is important to quality of life.

Methods: A cross-sectional survey was used to examine medication use associated with injurious and non-injurious falls in 21,900 community-dwelling adults, aged 60 years or over from 383 Australian general practices recruited for the DEPS-GP Project. Falls and injury from falls, medication use, depressive symptoms (Primary Health Questionnaire (PHQ-9)), clinical morbidity, suicidal ideation and intent, health status (SF-12 Health Survey), demographic and lifestyle information was reported in a standardised survey.

Findings: Respondents were 71.8 years (sd 7.7) …

Organisational Survey: Impact Of Healthway Funding On Currently Funded And Previously Funded Sar Organisations, Michael Rosenberg, Sarah French, Jenna Mitchell, Christina Mills, Lisa Wood

Research outputs pre 2011

Since 1992, organisations in receipt of Healthway funding have demonstrated consistently high levels of commitment to sponsorship requirements. In part, the high levels of commitment observed may reflect a trend towards organisations with similar values to Healthway applying for funding. Organisations with different values to Healthway may receive funding once and decide that the sponsorship does riot match the needs of their organisation. This may result in difficulties fo.r Healthway to access hard to reach organisations, or to establish longer-term partnerships with Sports, Arts or Racing (SAR) organisations that target high priority groups. To better understand how Healthway's requirements of …

Towards Automated Test Sequence Generation, Usman Farooq, Chiou Peng Lam, Huaizhong Li

Research outputs pre 2011

The article presents a novel control-flow based test sequence generation technique using UML 2.0 activity diagram, which is a behavioral type of UML diagram. Like other model-based techniques, this technique can be used in the earlier phases of the development process owing to the availability of the design models of the system. The activity diagram model is seamlessly converted into a colored Petri net. We proposed a technique that enables the automatic generation of test sequences according to a given coverage criteria from the execution of the colored Petri nets model. Two types of structural coverage criteria for AD based …

Historical Datasets Of Dugong (Dugong Dugon) Observations In The Kimberley Region Of Western Australia - Data Report - Report No. 2008-03, David K. Holley, R. I.T. Prince

Research outputs pre 2011

Research Need and Objective :

Many sections of the northern WA coastline have become heavily industrialised in the last three decades particularly throughout the Pilbara region where offshore and onshore oil and gas exploration and processing facilities are abundant. There have been recent moves to develop similar industry along the Kimberley coast to access the Browse Basin, a 140,000 Km2 offshore gas field approximately 300km off the Kimberley Coast. This has resulted in extensive debate and the need to define the natural values of this region, which is considered to be one of the world’s most ecologically diverse (WWF 2008). …

Analysis Of Information Remaining On Hand Held Devices For Sale On The Second Hand Market, Andrew Jones, Craig Valli, Iain Sutherland

Research outputs pre 2011

The ownership and use of mobile phones, Personal Digital Assistants and other hand held devices is now ubiquitous both for home and business use. The majority of these devices have a high initial cost, a relatively short period before they become obsolescent and a relatively low second hand value. As a result of this, when the devices are replaced, there are indications that they tend to be discarded. As technology has continued to develop, it has led to an increasing diversity in the number and type of devices that are available, and the processing power and the storage capacity of …

Promoting Healthy Weight In The Preschool Years: A Portfolio And Planning Guide To Address Barriers In Primary Care, Margaret Miller, Renee Campbell-Pope, Lydia Hearn

Research outputs pre 2011

The rapidly rising incidence of overweight and obesity in Australia, particularly among young children has led to an urgent need for effective prevention. Recent figures indicate that 15% of preschool children in Australia are overweight, and a further 6% are obese1,2, with rates rising steadily especially among children from lower socioeconomic groups.

Family, childcare, primary health care, early childhood education and the community are influential environments for young children3-7 with the potential to engage in an integrated approach to promote healthy weight and development of healthy eating and active lifestyle habits during the pre-school years5,8,9.

In 2006, the Child Health …