Physical Sciences and Mathematics Commons^™

Using In-Air Acoustic Vector Sensors For Tracking Moving Speakers, Muawiyath Shujau, Christian H. Ritz, I. Burnett

Faculty of Informatics - Papers (Archive)

This paper investigates the use of an Acoustic Vector Sensor (AVS) for tracking a moving speaker in real time through estimation of the Direction of Arrival (DOA). This estimation is obtained using the MUltiple SIgnal Classification (MUSIC) [1] algorithm applied on a time-frame basis. The performance of the AVS is compared with a SoundField Microphone which has similar polar responses to the AVS using time-frames ranging from 20 ms to 1 s. Results show that for 20 ms frames, the AVS is capable of estimating the DOA for both mono-tone and speech signals, which are both stationary and moving, with …

Efficient Rfid Authentication Scheme For Supply Chain Applications, Fei Bi, Yi Mu

Faculty of Informatics - Papers (Archive)

Radio Frequency Identification (RFID) technology has been widely used in supply chains to track and manage shipments. By tagging shipments with RFID tags, which can be remotely accessed by RFID readers, shipments can be identified and tracked in a supply chain. Security issues in RFID have been major concerns, since passive RFID tags have very weak computational power to support authentication. Sound authentication between tag and reader remains a challenging problem. In this paper, we provide a novel authentication scheme to protect tags from being tracked and identified by unauthorized readers and protect authorized readers against bogus tags. Our scheme …

Classification Cervical Cancer Using Histology Images, Rahmadwati, Golshah Naghdy, Montserrat Ros, Catherine Todd, E. Norachmawati

Faculty of Informatics - Papers (Archive)

This papers reports on methodologies and outcome of a study aiming at developing robust tool to evaluate and classify histology images of cervical cancer. Using the histology images acquired from the pathology laboratories in an Indonesian hospital, this study aims to classify cervical biopsy images based on four well known discriminatory features a) the ratio of nuclei to cytoplasm b) diameter of nuclei c) shape factor and d) roundness of nuclei. In this study, the cervical histology images are classified into three categories: 1) normal, 2) pre cancer and 3) malignant. The final system will take as input a biopsy …

Demystifying The Number Of The Beast In The Book Of Revelation: Examples Of Ancient Cryptology And The Interpretation Of The “666” Conundrum, M G. Michael

Faculty of Informatics - Papers (Archive)

As the year 2000 came and went, with the suitably forecasted fuse-box of utopian and apocalyptic responses, the question of "666" (Rev 13:18) was once more brought to our attention in different ways. Biblical scholars, for instance, focused again on the interpretation of the notorious conundrum and on the Traditionsgeschichte of Antichrist. For some of those commentators it was a reply to the outpouring of sensationalist publications fuelled by the millennial mania. This paper aims to shed some light on the background, the sources, and the interpretation of the “number of the beast”. It explores the ancient techniques for understanding …

Modelling Process For The Development Of Learning Content For Tertiary Education, Zhengui Wu, Parviz Doulai

Faculty of Informatics - Papers (Archive)

Along with the development of Internet technology, e-Learning as a flexible and convenient educational method has been widely accepted in tertiary education institutions to enhance and facilitate learning. By avoiding costly duplication and enabling the rapid creation of online courses, the employment of Learning Objects (LOs) and their reusability can benefit any educational institution when developing digital learning content for e-Learning. This paper proposes a learning content development target model utilizing LOs and related technologies to help content authors to design, develop and publish learning content at a minimized cost. The proposed model consists of identified variables that directly or …

A Network-Aware Virtual Machine Placement And Migration Approach In Cloud Computing, Jingtai Piao, Jun Yan

Faculty of Informatics - Papers (Archive)

Cloud computing represents a major step up in computing whereby shared computation resources are provided on demand. In such a scenario, applications and data thereof can be hosted by various networked virtual machines (VMs). As applications, especially data-intensive applications, often need to communicate with data frequently, the network I/O performance would affect the overall application performance significantly. Therefore, placement of virtual machines which host an application and migration of these virtual machines while the unexpected network latency or congestion occurs is critical to achieve and maintain the application performance. To address these issues, this paper proposes a virtual machine placement …

Graphs Of C*-Correspondences And Fell Bundles, Valentin Deaconu, Alexander Kumjian, David A. Pask, Aidan Sims

Faculty of Informatics - Papers (Archive)

We define the notion of a ˄-system of C*-correspondences associated to a higher-rank graph ˄. Roughly speaking, such a system assigns to each vertex of ˄ a C*- algebra, and to each path in ˄ a C*-correspondence in a way which carries compositions of paths to balanced tensor products of C*-correspondences. Under some simplifying assumptions, we use Fowler’s technology of Cuntz-Pimsner algebras for product systems of C*-correspondences to associate a C*-algebra to each ˄-system. We then construct a Fell bundle over the path groupoid G˄ and show that the C*-algebra of the ˄-system coincides with the reduced cross-sectional algebra of …

Connecting Museum Collections And Creator Communities: The Virtual Museum Of The Pacific Project, Frank Howarth, Peter Eklund

Faculty of Informatics - Papers (Archive)

[extract] “I’m interested in what you can’t see in collections...where this has been, what its function could be and how it still exists today...artists have a perspective that may assist in keeping some of these things in the way these objects always were made, but [also] ensuring that they evolve as well because that's part of the culture”. Artist Latai Taumopeau talking about a Ngatu, a traditional bark cloth from Tonga, in the Australian Museum collection.

Generalised Score And Wald Tests, Paul Rippon, J. C. W Rayner

Faculty of Informatics - Papers (Archive)

The generalised score and Wald tests are described and related to their nongeneralised versions. Two interesting applications are discussed. In the first a new test for the Behrens-Fisher problem is derived. The second is testing homogeneity of variances from multiple univariate normal populations.

Wavelet Based Nonlocal-Means Super-Resolution For Video Sequences, H Zheng, A Bouzerdoum, S L. Phung

Faculty of Informatics - Papers (Archive)

Video sequence resolution enhancement became a popular research area during the last two decades. Although traditional super-resolution techniques have been successful in dealing with image sequences, many constraints such as global translation between frames, have to be imposed to obtain good performance. In this paper, we present a new wavelet-based nonlocal-means (WNLM) framework to bypass the motion estimation stage. It can handle complex motion changes between frames. Compared with the nonlocal-means (NLM) super-resolution framework, the proposed method provides better result in terms of PSNR and faster processing.

Using Task Analysis To Design Intuitive Online Grocery Systems, Mark Freeman, Alison Freeman

Faculty of Informatics - Papers (Archive)

This paper presents a normative task model for modelling user interactions with online grocery stores. It is envisaged that using task models will aid system developers in building better systems to meet users’ needs, and hereby creating better system design processes. This paper will discuss the three main areas of user experience when completing the process of adding a product to an online trolley: attempting to retrieve the product, receiving the results of the retrieval attempt, and adding the product to the trolley. The normative task model presented is expected to help in the future design of online grocery systems …

Multi-Resolution Mean-Shift Algorithm For Vector Quantization, P L. M Bouttefroy, A Bouzerdoum, A Beghdadi, S L. Phung

Faculty of Informatics - Papers (Archive)

The generation of stratified codebooks, providing a subset of vectors at different scale levels, has become necessary with the emergence of embedded coder/decoder for scalable image and video formats. We propose an approach based on mean-shift, invoking the multi-resolution framework to generate codebook vectors. Applied to the entire image, mean-shift is slow because it requires each sample to converge to a mode of the distribution. The procedure can be sped up with three simple assumptions: kernel truncation, code attraction and trajectory attraction. Here we propose to apply the mean-shift algorithm to the four image subbands generated by a DWT, namely …

Usability As A Panacea, Mark Freeman, Matthew Bowden

Faculty of Informatics - Papers (Archive)

After implementation of a web-based application in a tertiary education environment, an expert review of this application was conducted. An analysis of the processes and results of the expert review of the web-based application is presented. The owners of the system implemented the recommendations of this expert review to resolve system issues. Through two rounds of expert evaluations, system modifications were made based on recommendations from the initial expert review. The concern that usability evaluations are used as a ‘cure-all solution’ to demonstrate to users that system owners are trying to resolve issues with the system is discussed. It should …

Adaptive Regularization For Image Restoration Using A Variational Inequality Approach, Matthew Kitchener, Abdesselam Bouzerdoum, Son Lam Phung

Faculty of Informatics - Papers (Archive)

In this paper, a generalized image restoration method is formulated as a variational inequality problem, whose solution is obtained using a dynamic system approach. In this method, the restored image and the regularization parameter are obtained simultaneously. In particular, the optimum regularization parameter is determined adaptively, depending on noise and image content. The restoration problem is presented in a generalized form so that it maybe be implemented using different norms; only L1 and L2 norms have been implemented in this paper. A comparison based on experimental results shows that the proposed method achieves comparable if not better performance as some …

Decoupled-Dfig Fault Ride-Through Strategy For Enhanced Stability Performance During Grid Faults, Lasantha G. Meegahapola, Damian Flynn, Tim Littler

Faculty of Informatics - Papers (Archive)

This paper proposes a decoupled fault ride-through strategy for a doubly fed induction generator (DFIG) to enhance network stability during grid disturbances. The decoupled operation proposes that a DFIG operates as an induction generator (IG) with the converter unit acting as a reactive power source during a fault condition. The transition power characteristics of the DFIG have been analyzed to derive the capability of the proposed strategy under various system conditions. The optimal crowbar resistance is obtained to exploit the maximum power capability from the DFIG during decoupled operation. The methods have been established to ensure proper coordination between the …

The Co-Universal C*-Algebra Of A Row-Finite Graph, Aidan Sims

Faculty of Informatics - Papers (Archive)

Let $E$ be a row-finite directed graph. We prove that there exists a $C^*$-algebra $\Cr{E}$ with the following co-universal property: given any $C^*$-algebra $B$ generated by a Toeplitz-Cuntz-Krieger $E$-family in which all the vertex projections are nonzero, there is a canonical homomorphism from $B$ onto $\Cr{E}$. We also identify when a homomorphism from $B$ to $\Cr{E}$ obtained from the co-universal property is injective. When every loop in $E$ has an entrance, $\Cr{E}$ coincides with the graph $C^*$-algebra $C^*(E)$, but in general, $\Cr{E}$ is a quotient of $C^*(E)$. We investigate the properties of $\Cr{E}$ with emphasis on the utility of co-universality …

Some Remarks On Hadamard Matrices, Jennifer Seberry, Marilena Mitrouli

Faculty of Informatics - Papers (Archive)

In this note we use combinatorial methods to show that the unique, up to equivalence, 5 × 5 (1, −1)-matrix with determinant 48, the unique, up to equivalence, 6 × 6 (1,−1)-matrix with determinant 160, and the unique, up to equivalence, 7 × 7 (1,−1)-matrix with determinant 576, all cannot be embedded in the Hadamard matrix of order 8. We also review some properties of Sylvester Hadamard matrices, their Smith Normal Forms, and pivot patterns of Hadamard matrices when Gaussian Elimination with complete pivoting is applied on them. The pivot values which appear reconfirm the above non-embedding results.

Overview On The Profile Measurement Of Turbine Blade And Its Developm, Huang Junhui, Wang Zhao, Gao Jianmin, Yanguang Yu

Faculty of Informatics - Papers (Archive)

Turbine machinery has an extraordinary wide range of applications in the aviation, aerospace, automotive, energy and many other industries. The turbine blade is one of the most important parts of turbine machinery, and the characteristic parameters, pressure ratio of the engine and rotating speed of the turbine are all related to the shape and size of blades. Therefore, the profile measurement of turbine blade is an essential issue in the blade machining processing, however, it is difficult and particular to establish the profile measurement of turbine blade because of its complicated shapes and space angles of the blades, and the …

Quasi-Orthogonal Space-Time-Frequency Codes In Mb-Ofdm Uwb, Le Chung Tran, Alfred Mertins, Tadeusz A. Wysocki

Faculty of Informatics - Papers (Archive)

Quasi-Orthogonal Space-Time-Frequency Codes (QOSTFCs) will be examined in this paper to advance either data rate or error performance in recently proposed Space-Time-Frequency Coded Multiband OFDM Ultra-Wideband (STFC MB-OFDM UWB) communication systems. It is shown that QOSTFCs can provide signi¯cantly better error performance, compared to the conventional MB-OFDM UWB (without STFCs) and to the Orthogonal STFCs (OSTFCs) of the same order, at the same data rate, without increasing the total transmission power. Another form of the enhancement would be that QOSTFCs can provide higher data rates with the same error performance, compared to OSTFCs.

Dynamic Modelling, Validating And Fine-Tuning Of Engineering Curriculum, Fazel Naghdy

Faculty of Informatics - Papers (Archive)

The undergraduate Engineering schools in Australia are required to embed and assess the Competency Standards defined by the Engineers Australia in their curriculum. At the same time, embedding graduate attributes in the curriculum has become an important element in the quality assurance processes of universities. The embedding and mapping are only the first step in a long term process. The mapping should be validated empirically and reviewed in a repeating cycle towards an effective and optimal curriculum. This will require a rigorous action learning process for creating and cyclic validation of a living curriculum. The conceptual development and early stages …

The Case For Ict Work-Integrated Learning From Graduates In The Workplace, Anthony J. Koppi, Sylvia L. Edwards, Judy Sheard, Fazel Naghdy, Wayne Brookes

Faculty of Informatics - Papers (Archive)

An online survey of recent ICT graduates in the workplace was carried out as part of a recent project funded by the Australian Learning and Teaching Council. The survey was concerned with the ICT curriculum in relation to workplace job requirements and university preparation for these requirements. The survey contained quantitative and qualitative components and findings from the former have been published (Koppi et al., 2009). This paper reports on a quantitative comparison of responses from graduates who had workplace experience and those who did not, and a qualitative analysis of text responses from all ICT graduates to open-ended questions …

Fuzzy Stability Control Of Robotic Manipulator With Input Delays, Haiping Du, Fazel Naghdy, David A. Stirling

Faculty of Informatics - Papers (Archive)

This paper studies the stabilisation control problem of a robotic manipulator with input delays. To deal with the highly nonlinear dynamics of a robotic manipulator, the model-based Takagi-Sugeno (T-S) fuzzy control strategy is applied. With representing the nonlinear robotic manipulator model as a T-S fuzzy model, sufficient conditions for designing a controller such that the system is stabilised with given decay rate are derived by constructing a less conservative Lyapunov-Krasovskii functional and using a tighter bounding technology for cross terms and the free weighting matrix approach. With appropriate derivation, all the required conditions are expressed as linear matrix inequalities (LMIs). …

C*-Algebras Of Tilings With Infinite Rotational Symmetry, Michael F. Whittaker

Faculty of Informatics - Papers (Archive)

A tiling with infinite rotational symmetry, such as the Conway– Radin Pinwheel Tiling, gives rise to a topological dynamical system to which an etale equivalence relation is associated. A groupoid C¤-algebra for a tiling is produced and a separating dense set is exhibited in the C*-algebra which encodes the structure of the topological dynamical system. In the case of a substitution tiling, natural subsets of this separating dense set are used to define an AT-subalgebra of the C*-algebra. Finally our results are applied to the Pinwheel Tiling.

Building A System For Managing Clinical Pathways Using Digital Pens, Linda L. Dawson, Virginia Plummer, Stephen Weeding, Terri Harlem, Bob Ribbons, David Waterhouse

Faculty of Informatics - Papers (Archive)

Background: A research team from Monash University and Peninsula Health, Victoria is undertaking a trial of digital pen and paper technology for clinical pathway management. Digital pen and paper allows for the capture of images of handwritten documents using an embedded camera in the pen which is matched with special patterns of dots on the paper. These digitised images can be uploaded to a database for analysis. Objectives: Clinical pathways have been adopted in most Australian hospitals to document and manage multidisciplinary care across a variety of acute care environments. Analysis of the information collected in paper-based clinical pathway documents …

Estimates Of Probable Dementia Prevalence From Population-Based Surveys Compared With Dementia Prevalence Estimates Based On Meta-Analyses, Kaarin J. Anstey, Richard A. Burns, Carole Birrell, David G. Steel, Kim M. Kiely, Mary A. Luszcz

Faculty of Informatics - Papers (Archive)

Background: National data on dementia prevalence are not always available, yet it may be possible to obtain estimates from large surveys that include dementia screening instruments. In Australia, many of the dementia prevalence estimates are based on European data collected between 15 and 50 years ago. We derived populationbased estimates of probable dementia and possible cognitive impairment in Australian studies using the Mini-Mental State Examination (MMSE), and compared these to estimates of dementia prevalence from meta-analyses of European studies.

Methods: Data sources included a pooled dataset of Australian longitudinal studies (DYNOPTA), and two Australian Bureau of Statistics National …

Investigation Of Relative Risk Estimates From Studies Of The Same Population With Contrasting Response Rates And Designs, Nicole M. Mealing, Emily Banks, Louisa R. Jorm, David G. Steel, Mark S. Clements, Kris D. Rogers

Faculty of Informatics - Papers (Archive)

Background: There is little empirical evidence regarding the generalisability of relative risk estimates from studies which have relatively low response rates or are of limited representativeness. The aim of this study was to investigate variation in exposure-outcome relationships in studies of the same population with different response rates and designs by comparing estimates from the 45 and Up Study, a population-based cohort study (self-administered postal questionnaire, response rate 18%), and the New South Wales Population Health Survey (PHS) (computer-assisted telephone interview, response rate ~60%).

Methods: Logistic regression analysis of questionnaire data from 45 and Up Study participants (n …

An Approach To Studying Location-Based Services Regulation In Australia, Roba Abbas

Faculty of Informatics - Papers (Archive)

Location-based Services (LBS) afford a means of positioning, tracing and tracking individuals and objects, for purposes such as emergency management, employee monitoring, and consumer convenience. This paper reviews the present LBS setting and expected developments in this space, with a particular focus on the implications for Australian research and regulatory efforts. The origins of LBS in the mobile-commerce field are explored, incorporating an appraisal of the underlying positioning technology, the stakeholders in the LBS value chain, and the regulatory environment in which these services are employed. There is an evident disparity between the implementation of LBS technologies and the introduction …

Some Mathematical Models Arising In Nano- And Bio-Technology, Yue Chan

Faculty of Informatics - Papers (Archive)

In this thesis, three mechanical models arising from nanoscale and biological systems are investigated, namely the dynamics of various nanostructures, the axial buckling of carbon nanotubes and nanopeapods, and the worm-like chain model for stretched semi-flexible molecules and the utilization of such a model for investigating molecular stretching in the connective tissue extracellular matrix.

Analyst-Mediated Contextualization Of Regulatory Policies, George Koliadis, Nirmit V. Desai, Nanjangud C. Nerandra, Aditya K. Ghose

Faculty of Informatics - Papers (Archive)

Increasing legislative and regulatory concerns have fueled an interest in effective and efficient tools for managing business process compliance within organizations. In particular, the key challenge is to understand high-level compliance policies in natural language, and interpret them for a particular usage context. These interpreted policies can then be represented in a formal language, and used to (for example) automatically verify compliance of business process executions against these policies. In this paper, we focus on the first part of this problem: interpreting regulatory policies — called contextualization. We employ a natural language parser to extract key phrases from the natural …

Action Recognition Based On A Bag Of 3d Points, Wanqing Li, Zhenyu Zhang, Zicheng Liu

Faculty of Informatics - Papers (Archive)

This paper presents a method to recognize human actions from sequences of depth maps. Specifically, we employ an action graph to model explicitly the dynamics of the actions and a bag of 3D points to characterize a set of salient postures that correspond to the nodes in the action graph. In addition, we propose a simple, but effective projection based sampling scheme to sample the bag of 3D points from the depth maps. Experimental results have shown that over 90% recognition accuracy were achieved by sampling only about 1% 3D points from the depth maps. Compared to the 2D silhouette …