Physical Sciences and Mathematics Commons^™

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 …

The 230 V Cbema Curve - Preliminary Studies, Sean T. Elphick, Victor W. Smith

Faculty of Informatics - Papers (Archive)

The ITI, formerly CBEMA, curve was developed by the Information Technology Industry Council of the United States of America. The curve describes an AC input voltage envelope which typically can be tolerated by most Information Technology (IT) Equipment. Although the curve ostensibly applies only to IT equipment it is often used throughout the electricity supply industry to provide an indication of the input voltage tolerance of a wide range of equipment. In spite of the fact that the curve was designed to apply to equipment supplied at 120 V 60 Hz nominal voltages it is widely used in Australia which …

Proof-Of-Knowledge Of Representation Of Committed Value And Its Applications, Willy Susilo, Yi Mu, Man Ho Allen Au

Faculty of Informatics - Papers (Archive)

We present a zero-knowledge argument system of representation of a committed value. Specifically, for commitments C = Commit1(y), D = Commit₂(x), of value y and a tuple x = (x₁, . . . , x_L), respectively, our argument system allows one to demonstrate the knowledge of (x, y) such that x is a representation of y to bases h₁, . . . , h_L. That is, y = h^x1₁ · · · h^xL_L . Our argument system is zero-knowledge and hence, it does not reveal anything …

An Estimation Method For Feedback Level Factor C Of A Self-Mixing Interferometry System, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Joe F. Chicharo

Faculty of Informatics - Papers (Archive)

This paper presents a fast estimation method for feedback level factor C of a self-mixing interferometry (SMI) system. The reconstruction of a displacement waveform using a SMI signal needs to know a C value. However, it is difficult to maintain a constant C value during the reconstruction process. We study the features of the reconstructed displacement waveforms incorporating different pre-set C values and classify waveforms into two types. Bisection method is introduced in our method for fast estimating C value. The effectiveness of our proposed method has been verified by both simulation and experimental data.

Planetary-Scale Rfid Services In An Age Of Uberveillance, Katina Michael, George Roussos, George Q. Huang, Arunabh Chattopadhyay, Rajit Gadh, B S. Prabhu, Peter Chu

Faculty of Informatics - Papers (Archive)

Radio-frequency identification has a great number of unfulfilled prospects. Part of the problem until now has been the value proposition behind the technology- it has been marketed as a replacement technique for the barcode when the reality is that it has far greater capability than simply non-line-of-sight identification, towards decision-making in strategic management and reengineered business processes. The vision of the Internet of Things has not eventuated but a world in which every object you can see around you carries the possibility of being connected to the internet is still within the realm of possibility. However incremental innovations may see …

Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim

Faculty of Informatics - Papers (Archive)

How to choose the best service provider (agent), which a service consumer can trust in terms of the quality and success rate of the service in an open and dynamic environment, is a challenging problem in many service-oriented applications such as Internet-based grid systems, e-trading systems, as well as service-oriented computing systems. This paper presents a Priority-Based Trust (PBTrust) model for service selection in general service-oriented environments. The PBTrust is robust and novel from several perspectives. (1) The reputation of a service provider is derived from referees who are third parties and had interactions with the provider in a rich …

Ste3d-Cap: Stereoscopic 3d Captcha, Willy Susilo, Yang-Wai Chow, Huayu Zhou

Faculty of Informatics - Papers (Archive)

We present STE3D-CAP (pronounced as “steed-cap” /'stidkæp/), a text-based CAPTCHA that is built from stereoscopic 3D images. This is a completely new direction in CAPTCHA techniques. Our idea is to incorporate stereoscopic 3D images in order to present the CAPTCHA challenge in 3D, which will be easy for humans to read (as the text stands out in the 3D scene) but hard for computers. The main idea is to produce a stereo pair, two images of the distorted 3D text objects generated from two different camera/eye viewpoints, that are presented to a human user’s left and right eyes, respectively. When …

Monitoring Intelligent Distribution Power Systems: A Power Quality Plan, Neil R. Browne, Timothy J. Browne, Sean T. Elphick

Faculty of Informatics - Papers (Archive)

Power system monitoring capabilities and requirements are evolving rapidly. The traditional monitoring framework in Australian distribution networks involves biannual readings of maximum demand at each distribution substation. As utilities respond to developments in metering and communications technology, automated collection and retrieval of quasi-real-time system data between substations and central repositories is now feasible. This gives network managers a significantly increased understanding of distribution network dynamic activity such as daily and seasonal load profiles. This leads to the increased ability of utilities to exploit metering data for power quality analysis purposes. This paper examines the scope for, and challenges associated with, …

Information Retrieval And Social Tagging For Digital Libraries Using Formal Concept Analysis, Peter W. Eklund, Peter Goodall, Timothy Wray

Faculty of Informatics - Papers (Archive)

This paper reports a novel semantic web application developed to deliver a collaborative tagging system for a digital on-line museum. The key features of our application – called the Virtual Museum of the Pacific – concern the browsing and retrieval interface based on Formal Concept Analysis, the extensible distributed data model to support collaborative tagging and its web services implementation.

On The Combination Of Local Texture And Global Structure For Food Classification, Zhimin Zong, Duc Thanh Nguyen, Philip O. Ogunbona, Wanqing Li

Faculty of Informatics - Papers (Archive)

This paper proposes a food image classification method using local textural patterns and their global structure to describe the food image. In this paper, a visual codebook of local textural patterns is created by employing Scale Invariant Feature Transformation (SIFT) interest point detector with the Local Binary Pattern (LBP) feature. In addition to describing the food image using local texture, the global structure of the food object is represented as the spatial distribution of the local textural structures and encoded using shape context. We evaluated the proposed method on the Pittsburgh Fast-Food Image (PFI) dataset. Experimental results showed that the …

On Optimising Route Discovery For Multi-Interface And Power-Aware Nodes In Heterogeneous Manets, Huda Alaamri, Mehran Abolhasan, Tadeusz A. Wysocki, Justin Lipman

Faculty of Informatics - Papers (Archive)

This paper presents a new routing discovery strategy for heterogeneous MANETs. Node heterogeneity is modeled in terms of: types and number of different interfaces, power, and transmission ranges. Our proposed route discovery algorithm is implemented on the top of On-demand Tree-based Routing Protocol (OTRP) and hence it is called OTRP Heterogeneity-Aware (OTRP HA). OTRP HA utilizes node heterogeneity and optimizes route discovery to reduce overheads and ensures connectivities between different types of nodes with different interfaces. Each node makes its own decision to participate in the route discovery process according to its location, local density, and available resources. Simulation results …