Physical Sciences and Mathematics Commons^™

A Real-Time Facial Expression Recognition System For Online Games, Ce Zhan, Wanqing Li, Philip Ogunbona, Farzad Safaei

Faculty of Informatics - Papers (Archive)

Multiplayer online games (MOGs) have become increasingly popular because of the opportunity they provide for collaboration, communication, and interaction. However, compared with ordinary human communication, MOG still has several limitations, especially in communication using facial expressions. Although detailed facial animation has already been achieved in a number of MOGs, players have to use text commands to control the expressions of avatars. In this paper, we propose an automatic expression recognition system that can be integrated into an MOG to control the facial expressions of avatars. To meet the specific requirements of such a system, a number of algorithms are studied, …

The Theory Of Quaternion Orthogonal Designs, Jennifer Seberry, K. Finlayson, S. Spense Adams, Tadeusz A. Wysocki, Tianbing Xia, Beata J. Wysocki

Faculty of Informatics - Papers (Archive)

Over the past several years, there has been a renewed interest in complex orthogonal designs for their application in space-time block coding. Motivated by the success of this application, this paper generalizes the definition of complex orthogonal designs by introducing orthogonal designs over the quaternion domain. This paper builds a theory of these novel quaternion orthogonal designs, offers examples, and provides several construction techniques. These theoretical results, along with the results of preliminary simulations, lay the foundation for developing applications of these designs as orthogonal space-time-polarization block codes.

Formative Versus Reflective Measurement Models: Two Applications Of Formative Measurement, T. Coltman, T. M. Devinney, D. F. Midgley, S. Venaik

Faculty of Informatics - Papers (Archive)

This paper presents a framework that helps researchers to design and validate both formative and reflective measurement models. The framework draws from the existing literature and includes both theoretical and empirical considerations. Two important examples, one from international business and one from marketing, illustrate the use of the framework. Both examples concern constructs that are fundamental to theory-building in these disciplines, and constructs that most scholars measure reflectively. In contrast, applying the framework suggests that a formative measurement model may be more appropriate. These results reinforce the need for all researchers to justify, both theoretically and empirically, their choice of …

In Pursuit Of A Sustainable Supply Chain: Insights From Westpac Banking Corporation, Byron Keating, Ali Quazi, Anton Kriz, Tim Coltman

Faculty of Informatics - Papers (Archive)

Purpose – The aim of this paper is to provide clues to industry and academia on how best to approach the challenge of developing a sustainable supply chain.

Design/methodology/approach – A case study was undertaken of the Westpac Banking Corporation – one of the world's most socially responsible banks – to examine how they approached the challenge of managing corporate social responsibility (CSR) in their supply chain.

Findings – This paper highlights some of the challenges and opportunities associated with extending corporate governance beyond the firm boundary. Specific attention is given to a discussion of assessment and governance tools.

Research …

Flicker Attenuation—Part I: Response Of Three-Phase Induction Motors To Regular Voltage Fluctuations, S. Tennakoon, S. Perera, D. Robinson

Faculty of Informatics - Papers (Archive)

Voltage fluctuations leading to lamp flicker that originate in one place in a power system tend to propagate to other parts of the network with some level of attenuation depending on the network impedances and the loads connected. Numerous subsynchronous- type frequency components exist in these voltage fluctuations that are responsible for lamp flicker. The rudimentary theory and the experimental measurements support the idea that industrial load bases, which contain a large percentage of mains-connected induction motors, tend to attenuate flicker better compared to residential load bases having mainly passive loads. This paper reports on the response of three-phase induction …

Application Of Quasi-Orthogonal Space-Time-Frequency Codes In Mb-Ofdm Uwb, Alfred Mertins, Le Chung Tran

Faculty of Informatics - Papers (Archive)

This paper examines the application of Quasi-Orthogonal Space-Time-Frequency Codes (QOSTFCs) to advance either data rate or error performance in recently proposed Space-Time-Frequency Coded Multiband OFDM Ultra-Wideband (STFC MB-OFDM UWB) communications systems. It is shown that QOSTFCs can provide significantly 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. In other words, QOSTFCs can provide higher data rates with the same error performance, compared to OSTFCs.

Issues In Australian Ict Education, Tony J. Koppi, Fazel Naghdy, Joe F. Chicharo

Faculty of Informatics - Papers (Archive)

This session at the Australian Software Engineering Conference is concerned with ICT education from the holistic perspective of preparation in high schools, the university experience, transition to the workforce, and the contribution by industry, government, and professional bodies. The project to ascertain the issues and challenges facing the national ICT education sector is supported by the Carrick institute as a discipline-based initiative. Consultations to date with various stakeholders have revealed numerous concerns that include: the dispersed nature of the ICT sector; erroneous perceptions of ICT disciplines; decline in enrolments; gender imbalance; lack of industry involvement; and balancing knowledge with generic …

Application Of Fuzzy Narx To Human Gait Modelling And Identification, Seyed Hesami, Fazel Naghdy, David A. Stirling, Harold C. Hill

Faculty of Informatics - Papers (Archive)

A new modelling and classification approach for human gait is proposed. Body movements are obtained using a sensor suit recording inertial signals that are subsequently modelled on a humanoid frame with 23 degrees of freedom (DOF). Measured signals include position, velocity, acceleration, orientation, angular velocity and angular acceleration. The identification and modelling method segments the stream of non–linear movement data on the basis of the features extracted from the sensor signals. A model is then created for the movement of every individual. This model is used as a dynamic finger print for that specific individual. In the future stages of …

3d Geometric Modelling Of Hand-Woven Textile, Hooman Shidanshidi, Fazel Naghdy, Golshah Naghdy, Diana Wood Conroy

Faculty of Informatics - Papers (Archive)

Geometric modeling and haptic rendering of textile has attracted significant interest over the last decade. A haptic representation is created by adding the physical properties of an object to its geometric configuration. While research has been conducted into geometric modeling of fabric, current systems require time-consuming manual recognition of textile specifications and data entry. The development of a generic approach for construction of the 3D geometric model of a woven textile is pursued in this work. The geometric model would be superimposed by a haptic model in the future work. The focus at this stage is on hand-woven textile artifacts …

Evaluating The Implementation Of Emr Systems From The Perspective Of Health Professionals, Yung-Yu Su, John A. Fulcher, Khin Than Win, Herng-Chia Chiu, Gui-Fen Chiu

Faculty of Informatics - Papers (Archive)

In health informatics, the "updated DeLone and McLean IS success model" is reviewed as a mature model in measuring health information system (HIS) success. This research provided an evaluation model to estimate the implementation of electronic medical records (EMR) systems from a health professional perspective by combined the updated DeLone and McLean IS success model, data quality management model, and EMR systems safety attributes. Based on evidence-based management (EBM), this research could be regarded as an empirical example for further EMR systems research since it not only provided a model to measure the Taiwanese EMR systems in two hospitals by …

On Binary Reflected Gray Codes And Functions, Martin W. Bunder, Keith P. Tognetti, Glen Wheeler

Faculty of Informatics - Papers (Archive)

The Binary Reflected Gray Code function b is defined as follows: If m is a nonnegative integer, then b(m) is the integer obtained when initial zeros are omitted from the binary reflected Gray code of length m. This paper examines this Gray code function and its inverse and gives simple algorithms to generate both. It also simplifies Conder’s result that the jth letter of the kth word of the binary reflected Gray code of length n, is

(2ⁿ − 2^n−j − 1

[2ⁿ − 2^n−j−1 − k/2]) mod 2,

by replacing the binomial coefficient by

[(k-1)/(2 …

An Energy-Aware Multilevel Clustering Algorithm For Wireless Sensor Networks, Xinfang Yan, Jiangtao Xi, Joe F. Chicharo, Yanguang Yu

Faculty of Informatics - Papers (Archive)

Clustering sensors nodes as the basic of routing is an efficient mechanism for prolonging the lifetime of wireless sensor networks. In this paper, the high-efficient multilevel clustering is abstracted as a root tree which has the performances of the minimal relay set and the maximal weight according to graph theory. A mathematical model for the clustering virtual backbone is built. Based on the model, an algorithm called energy-aware multilevel clustering (EAMC) is proposed. The EAMC can reduce the number of relays used for data transmission by minimizing the amount of the nodes in the root tree (that is cluster-head). Furthermore, …

Ontology-Based Knowledge Representation For A P2p Multi-Agent Distributed Intrusion Detection System, Dayong Ye, Quan Bai, Minjie Zhang

Faculty of Informatics - Papers (Archive)

Many research efforts on application of ontology in network security have been done in the past decade. However, they mostly stop at initial proposal or focus on framework design without detailed representation of intrusion or attack and relevant detection knowledge with ontology. In this paper, the design and implementation of ontology-based knowledge representation for a peer-to-peer multi-agent distributed intrusion detection system (ontology-based MADIDS) are introduced. An example which demonstrates the representation of an attack with ontology and the relevant detection process is also presented. In ontology-Based MADIDS, ontology technique enables peers in the system and agents in one peer to …

Varieties Of Abelian Topological Groups And Scattered Spaces, Carolyn E. Mcphail, Sidney A. Morris

Faculty of Informatics - Papers (Archive)

The variety of topological groups generated by the class of all abelian k_omega-groups has been shown to equal the variety of topological groups generated by the free abelian topological group on [0,1]. In this paper it is proved that the free abelian topological group on a compact Hausdorff space, X, generates the same variety if and only if X is not scattered.

When To Use A Multi Agent System?, Paul Bogg, Ghassan Beydoun, Graham Low

Faculty of Informatics - Papers (Archive)

The decision of which development approach to adopt (e.g. traditional, object oriented, agent oriented) is often taken after identifying the specific features of the problem. If agent oriented software engineering (AOSE) is to be taken seriously as a software engineering paradigm, then a clearly identifiable set of criteria of when to apply it, as distinguished from other alternatives such as object-oriented practices, is necessary. The paper is part of an effort to determine when is best to adopt a Multi Agent System approach, identifying a number of critical factors to include in a decision framework.

Comment On "General Equilibrium Shape Equations Of Polymer Chains", Ngamta Thamwattana, James M. Hill

Faculty of Informatics - Papers (Archive)

In this Comment, we point out that the Euler-Lagrange equations, which are referred to as the general equilibrium shape equations presented by Zhang et al. [Phys. Rev. E 70, 051902 (2004)] are incorrect, along with equations derived from them. The correct equations are provided here and they are cross-checked using certain energy functions previously presented in the literature. Further, with the use of the correct equations, we present new numerical results, which for the values of the constants given by Zhang et al. do not give rise to the physical behavior observed for DNA by those authors. However, the correct …

Calculation Of A Risk Measure For The Net System Load Profile, Ken Russell, Pietro Cerone, Vivien Challis

Faculty of Informatics - Papers (Archive)

No abstract provided.

Design And Analysis Of Clustered, Unmatched Resource Selection Studies, Robert Graham Clark, Tanya Strevens

Faculty of Informatics - Papers (Archive)

Studies which measure animals’ positions over time are a vital tool in understanding the process of resource selection by animals. By comparing a sample of locations that are used by animals with a sample of available points, the types of locations that are preferred by animals can be analysed by using logistic regression. Random-effects logistic regression has been proposed to deal with the repeated measurements that are observed for each animal, but we find that this is not feasible in studies where the sample of available points cannot readily be matched to specific animals. Instead, we investigate the use of …

Parameters Estimation For Ssms: Ql And Aql Approaches, Raed Alzghool, Yan-Xia Lin

Faculty of Informatics - Papers (Archive)

This paper considers parameter estimation for state-space models (SSMs). We propose quasi-likelihood (QL) and asymptotic quasilikelihood (AQL) approaches for the estimation of state-space models. The asymptotic quasi-likelihood (AQL) utilises a nonparametric kernel estimator of the conditional variance covariances matrix Σt to replace the true Σt in the standard quasi-likelihood. The kernel estimation avoids the risk of potential miss-specification of Σt and thus make the parameter estimator more robust. This has been further verified by empirical studies carried out in this paper.

A Supervised Learning Approach For Imbalanced Data Sets, Giang H. Nguyen, Abdesselam Bouzerdoum, Son Lam Phung

Faculty of Informatics - Papers (Archive)

This paper presents a new learning approach for pattern classification applications involving imbalanced data sets. In this approach, a clustering technique is employed to resample the original training set into a smaller set of representative training exemplars, represented by weighted cluster centers and their target outputs. Based on the proposed learning approach, four training algorithms are derived for feed-forward neural networks. These algorithms are implemented and tested on three benchmark data sets. Experimental results show that with the proposed learning approach, it is possible to design networks to tackle the class imbalance problem, without compromising the overall classification performance.

Collisionless Shock Resolution In Nematic Liquid Crystals, Gaetano Assanto, Timothy R. Marchant, Noel Smyth

Faculty of Informatics - Papers (Archive)

The diffractive resolution on a collisionless shock formed along the spatial profile of a beam in a nematic liquid crystal is considered, this material being an example of a self-focusing, nonlocal medium. It is found that the shock is resolved through the formation of an undular bore structure which persists for experimentally relevant propagation distances due to nonlocality delaying the onset of modulational instability. Both 1+1 and 2+1 dimensional bores with circular symmetry are considered (termed line and circular bores, respectively). A semianalytical solution is developed for the line undular bore, approximating it as a train of uniform solitary waves. …

Combined User Multiplexing And Data Modulation Through Non-Binary Turbo Codes For Uwb, Keni Popovski, Tadeusz A. Wysocki, Beata J. Wysocki

Faculty of Informatics - Papers (Archive)

With significant research being conducted in Ultra Wideband communications to increase error performance, this paper proposes a combination of user multiplexing and data encoding to achieve a BER improvement. Through the use of non-binary turbo coding, data is modulated to form a time hopping code which is applied to a time-reversed UWB system. Comparative results with conventional binary coding are given, showing the possibility for BER improvements in systems with a low number of users. Slight performance degradations for a large number of users exist. The effects of a user applying turbo coding on other users not applying forward error …

Hierarchical Identity-Based Online/Offline Encryption, Zhongren Liu, Li Xu, Zhide Chen, Yi Mu, Fuchun Guo

Faculty of Informatics - Papers (Archive)

The notion of identity-based online/offline encryption (IBOOE) was recently introduced by Guo, Mu and Chen in FC 2008. In an IBOOE system, the encryption is split into online and offline phases. The offline phase is performed prior to the arrival of a message and the recipient's public key (or,identity). The online phase is performed very efficiently after knowing the message and public key. The IBOOE scheme is particularly useful for devices that have very low computation power since partof computation is conducted while the device is not busy. In this paper, we extend the notion of IBOOE to the hierarchical …

Mobile Ad-Hoc Network Key Management With Certificateless Cryptography, Zhenfei Zhang, Willy Susilo, Raad Raad

Faculty of Informatics - Papers (Archive)

In this paper, we present an idea of adopting certificateless public key encryption (CL-PKE) schemes over mobile ad hoc network (MANET), which has not been explored before. In current literature, essentially there exists two main approaches, namely the public key cryptography and identity-based (ID-based) cryptography. Unfortunately, they both have some inherent drawbacks. In the public key cryptography system, a certificate authority (CA) is required to issue certificates between users' public keys and private keys to ensure their authenticity, whilst in an ID-based cryptography system, users' private keys are generated by a key generation center (KGC), which means the KGC knows …

Model Eco-Systems: Preliminary Work, Aditya K. Ghose, George Koliadis

Faculty of Informatics - Papers (Archive)

Modeling is core software engineering practice. Conceptual models are constructed to establish an abstract understanding of the domain among stakeholders. These are then refined into computational models that aim to realize a conceptual specification. The refinement process yields sets of models that are initially incomplete and inconsistent by nature. The aim of the engineering process is to negotiate consistency and completeness toward a stable state sufficient for deployment / implementation. This paper presents the notion of a model ecosystem, which permits the capability to guide analyst edits toward stability by computing consistency and completeness equilibria for conceptual models during periods …

Making Carrier Frequency Offset An Advantage For Orthogonal Frequency Division Multiplexing, Xiaojing Huang

Faculty of Informatics - Papers (Archive)

Contrary to the common belief that the carrier frequency offset (CFO) in an orthogonal frequency division multiplexing (OFDM) system would adversely impact on system performance, this paper shows that the CFO actually has the effect of linear precoding among transmitted data symbols and hence can be exploited to improve the diversity performance over frequency-selective fading channels. With both analysis and Monte Carlo simulation, it is proved that an OFDM system with CFO equal to half of the subcarrier spacing can potentially achieve the performance of diversity order four by the maximum-likelihood detection and demonstrate a 5 dB improvement using the …

Analytical Study Of The Rotation Spreading Matrix Of Block Spread Ofdm With Mmse Equalization, Ibrahim S. Raad, Xiaojing Huang

Faculty of Informatics - Papers (Archive)

This paper presents an analytical study on the new spreading matrix for block spread OFDM known as the rotation spreading matrix and simulates the BER performance in the MMSE equation. In (I. Raad et al., 2006) a new spreading matrix was presented for block spread OFDM (BSOFDM) known as the rotation spreading matrix. It was shown to greatly improve on the existing spreading matrices such as the Hadamard and the rotated Hadamard matrices in frequency selective channels such as the ultra wide band and slow fading channels. This paper studies the effect of increasing the block size in BSOFDM using …

A New Link Scheduling Algorithm For Concurrent Tx/Rx Wireless Mesh Networks, Kwan-Wu Chin

Faculty of Informatics - Papers (Archive)

Wireless routers equipped with smart antennas are capable of forming beams to neighboring devices to transmit/receive multiple packets simultaneously, hence achieving high network capacity. This however is dependent on the link scheduling algorithm employed by these routers. To this end, we describe a simple link activation algorithm that tradeoffs path length to increase network capacity. We show via analysis and simulation that the proposed algorithm improves network capacity and lowers end-to-end delay despite a slight increase in path length.

A Generic Construction Of Identity-Based Online/Offline Signcryption, Dongdong Sun, Yi Mu, Willy Susilo

Faculty of Informatics - Papers (Archive)

Signcryption has clear advantage over traditional sign-then-encrypt schemes. However, the computational overhead for signcryption is still too heavy when it is applied to resource-constraint systems. In this paper, we propose a generic construction of the identity-based online/offline signcryption, where most of computations are carried out when the associated message is still unavailable and the online part of our scheme does not require any exponent computations and therefore is very efficient. Our scheme isgeneric and identity-based, in the sense it is independent of the selection of signature and encryption algorithms. Our scheme possesses the properties of ciphertext indistinguishability (IND-gCCA2) and existentially …

Using A Novel Variable Block Size Image Compression Algorithm For Hiding Secret Data, F. Keissarian

Faculty of Informatics - Papers (Archive)

This paper presents a data hiding scheme that hides the data in the compression domain of a digital image. A quadtree decomposition algorithm decomposes the host image into blocks of variable sizes according to histogram analysis of the block residuals. Variable block sizes are then encoded at different rates based on their visual activity levels. The majority of secrete data are embedded into the smooth area of the image, while a small portion of the secret data are hidden in the compression codes of the high detailed blocks. Experimental results confirm that the proposed scheme can embed a large amount …