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Articles 1411 - 1440 of 4868

Full-Text Articles in Physical Sciences and Mathematics

Intelligent Load Management In Microgrids, J Kennedy, Philip Ciufo, Ashish Agalgaonkar Jan 2012

Intelligent Load Management In Microgrids, J Kennedy, Philip Ciufo, Ashish Agalgaonkar

Faculty of Informatics - Papers (Archive)

The increased levels of distributed generator (DG) penetration and the customer demand for high levels of reliability have attributed to the formation of the Microgrid concept. The Microgrid concept contains a variety of technical challenges, including load management and anti-islanding protection discrimination strategies. This paper provides a novel scheme in which loads and DG are able to detect the conditions where the load of the island cannot be sufficiently supplied. In these instances, a load shedding algorithm systematically removes loads from the system until an island can be maintained within satisfactory operating limits utilising the local DG. The concept of …


Efficient Fair Conditional Payments For Outsourcing Computations, Xiaofeng Chen, Jin Li, Willy Susilo Jan 2012

Efficient Fair Conditional Payments For Outsourcing Computations, Xiaofeng Chen, Jin Li, Willy Susilo

Faculty of Informatics - Papers (Archive)

The outsourcing computations in distributed environments suffer from the trust problems between the outsourcer and the workers. All existing solutions only assume the rational lazybut- honest workers. In this paper, we first introduce the rational lazy-and-partially-dishonest workers in the outsourcing computation model. In addition, we propose a new fair conditional payment scheme for outsourcing computation that is only based on traditional electronic cash systems. The proposed construction uses a semitrusted third party T to achieve the fairness and efficiency. However, is only involved in the protocol in the exceptional case, namely in the case of disputes. Moreover, since neither the …


Location Privacy Under Dire Threat As 'Uberveillance' Stalks The Streets, Katina Michael, Roger Clarke Jan 2012

Location Privacy Under Dire Threat As 'Uberveillance' Stalks The Streets, Katina Michael, Roger Clarke

Faculty of Informatics - Papers (Archive)

Citizen consent and issues surrounding location-based people-tracking - location-tracking - smart phones - covert tracking - CCTV cameras - mobile phones - warrantless tracking - Australian Mobile Telecommunications Association (AMTA) new industry guidelines - compliance with privacy legislation - need for a location privacy protection act or GPS act.


Editorial: Social Implications Of Technology: "Il Buono, Il Brutto, Il Cattivo", Katina Michael Jan 2012

Editorial: Social Implications Of Technology: "Il Buono, Il Brutto, Il Cattivo", Katina Michael

Faculty of Informatics - Papers (Archive)

Late last year, IEEE SSIT was invited to put together a paper for the centennial edition of the Proceedings of the IEEE for publication in May 2012 [1]. The article, "Social Implications of Technology: Past, Present, and Future," brought together five members of SSIT with varying backgrounds, and involved two intense months of collaboration and exchange of ideas. I personally felt privileged to be working with Karl D. Stephan, Emily Anesta, Laura Jacobs, and M.G. Michael on this project.


Human Rights, Regulation, And National Security (Introduction), Simon Bronitt, Katina Michael Jan 2012

Human Rights, Regulation, And National Security (Introduction), Simon Bronitt, Katina Michael

Faculty of Informatics - Papers (Archive)

Law disciplines technology, though it does so in a partial and incomplete way. This fact is refl ected in the old adage that technology outstrips the capacity of law to regulate it. The rise of new technologies poses a signifi cant threat to human rights. The pervasive use of closedcircuit television (CCTV), as well as mobile CCTV, telecommunications interception, and low-cost audiovisual recording and tracking devices (some of these discreetly wearable), extend the power of the state and corporations to signifi cantly intrude into the lives of citizens.


You Talkin' To Me?, Katina Michael Jan 2012

You Talkin' To Me?, Katina Michael

Faculty of Informatics - Papers (Archive)

Advancing knowledge through robust research is an honourable aim- being scientific, finding the right methodology, executing project phases meticulously, and reporting on the outcomes as objectively and accurately as possible. But may I begin my inaugural editorial by saying that an even higher ideal to advancing knowledge is critiquing it as it happens. Reflective practice is not just something to be done by academics in their teaching- reflective practice is what we should all be doing as we go about undertaking our various day-to-day work tasks. For the engineer engaged in research and development, whether in industry or government, reflective …


Rfid-Enabled Healthcare Applications, Issues And Benefits: An Archival Analysis (1997-2011), S F. Wamba Jan 2012

Rfid-Enabled Healthcare Applications, Issues And Benefits: An Archival Analysis (1997-2011), S F. Wamba

Faculty of Informatics - Papers (Archive)

In this paper, a comprehensive review of articles published between 1997 and 2011 in the Journal of Medical Systems (JMS) on RFID technology is presented. A total of 22 papers are analyzed using a classification framework that has three dimensions: RFID-enabled healthcare applications, RFID-enabled healthcare issues, and RFID-enabled healthcare benefits. In addition, an invitation sent to all authors of the papers accepted for the special issue on RFID for the JMS allows them to position their various papers within the classification framework. Finally, a list of future research directions is presented.


Business Value Of Rfid-Enabled Healthcare Transformation Projects, Anand Abijith, S. F. Wamba Jan 2012

Business Value Of Rfid-Enabled Healthcare Transformation Projects, Anand Abijith, S. F. Wamba

Faculty of Informatics - Papers (Archive)

Purpose – This paper aims to assess the business value realised from radio frequency identification (RFID)-enabled healthcare transformation projects as compared with other industries. The paper starts with a review of RFID technology in the healthcare industry and further extends to an in-depth analysis of mini-case studies collected from RFID Journal, a leading professional journal dedicated to RFID technology, in order to identify the major benefits of the implementation of RFID systems as well as its business value achieved. In addition, there is further analysis that is being carried out on other industries to have an overview of the benefits …


Attrition From Australian Ict Degrees - Why Women Leave, Madeleine R. H Roberts, Tanya J. Mcgill, Peter N. Hyland Jan 2012

Attrition From Australian Ict Degrees - Why Women Leave, Madeleine R. H Roberts, Tanya J. Mcgill, Peter N. Hyland

Faculty of Informatics - Papers (Archive)

Student attrition is of particular concern in the field of ICT because the industry faces staffing shortfalls, generally and a noticeable lack of female employees. This paper explores the reasons female students give for leaving their ICT courses. An online survey of early leavers from four Australian universities was conducted. The results show that, for many students, it is a combination of issues that leads to their withdrawal. Contrary to expectations, few female ex-students had experienced serious life events that necessitated their withdrawal or indicated that negative behaviour or attitudes had contributed to their decision to leave. More commonly female …


Evaluating The Volatility Forecasting Performance Of Best Fitting Garch Models In Emerging Asian Stock Markets, Chaiwat Kosapattarapim, Yan-Xia Lin, Michael Mccrae Jan 2012

Evaluating The Volatility Forecasting Performance Of Best Fitting Garch Models In Emerging Asian Stock Markets, Chaiwat Kosapattarapim, Yan-Xia Lin, Michael Mccrae

Faculty of Informatics - Papers (Archive)

While modeling the volatility of returns is essential for many areas of finance, it is well known that financial return series exhibit many non-normal characteristics that cannot be captured by the standard GARCH model with a normal error distribution. But which GARCH model and which error distribution to use is still open to question, especially where the model that best fits the in-sample data may not give the most effective out-of-sample volatility forecasting ability. Approach: In this study, six simulated studies in GARCH(p,q) with six different error distributions are carried out. In each case, we determine the best fitting GARCH …


A Novel Scheduler For Concurrent Tx/Rx Wireless Mesh Networks With Weighted Links, Kwan-Wu Chin, Sieteng Soh, Chen Meng Jan 2012

A Novel Scheduler For Concurrent Tx/Rx Wireless Mesh Networks With Weighted Links, Kwan-Wu Chin, Sieteng Soh, Chen Meng

Faculty of Informatics - Papers (Archive)

This paper considers the NP-hard problem of scheduling weighted links in concurrent transmit/receive wireless mesh networks. The problem generalizes existing works to links with weight wij ≥ 1. We propose an O(|V|2) algorithm, where V is the set of routers, that is orders of magnitude faster than computationally intensive approaches that use the well-known Goemans-Williamson (GWA)'s maximum cut algorithm and also brute-force. Our algorithm generates schedules, on average, with at most 3% and 9% fewer links than the GWA and brute-force approaches respectively.


Efficient Oblivious Transfers With Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan Jan 2012

Efficient Oblivious Transfers With Access Control, Jinguang Han, Willy Susilo, Yi Mu, Jun Yan

Faculty of Informatics - Papers (Archive)

Oblivious transfer (OT) is a protocol where a receiver can obtain t-out-of-n services from the sender without releasing anything about his choices. OT can be used to protect user’s privacy. In principle, any user can interact with a server to request some services. This might allow some undesirable users to obtain services from the server. How to ensure that only the authorized receivers can obtain services obliviously is a daunting task. In this paper, we introduce oblivious signature based-on envelope (OSBE) to OT and propose two novel OT schemes, which only allow the legitimate receivers to obtain services obliviously. The …


Further Analysis Of A Practical Hierarchical Identity-Based Encryption Scheme, Ying Sun, Yong Yu, Yi Mu Jan 2012

Further Analysis Of A Practical Hierarchical Identity-Based Encryption Scheme, Ying Sun, Yong Yu, Yi Mu

Faculty of Informatics - Papers (Archive)

No abstract provided.


Efficient And Secure Stored-Value Cards With Leakage Resilience, Fuchun Guo, Yi Mu, Willy Susilo Jan 2012

Efficient And Secure Stored-Value Cards With Leakage Resilience, Fuchun Guo, Yi Mu, Willy Susilo

Faculty of Informatics - Papers (Archive)

Stored-value cards (SVCs) are a kind of smartcards that can be used to store monetary values. SVCs have demonstrated a wide range of applications in commerce. SVCs are in general tamper-resistant, but they are very computationally weak and their security mechanisms are also weak against side-channel attacks. In this paper, we propose an efficient and secure stored-value card system. With the help of pre-computations, storedvalue cards in our scheme are only required to perform simple arithmetic operations and bitwise comparisons. Our system especially for SVCs is secure with unbounded computational leakage resilience. Our novel scheme provides a practical solution to …


Frequency Selection In Absolute Phase Maps Recovery With Two Frequency Projection Fringes, Yi Ding, Jiangtao Xi, Yanguang Yu, Wengqing Cheng, Shu Wang, Joe F. Chicharo Jan 2012

Frequency Selection In Absolute Phase Maps Recovery With Two Frequency Projection Fringes, Yi Ding, Jiangtao Xi, Yanguang Yu, Wengqing Cheng, Shu Wang, Joe F. Chicharo

Faculty of Informatics - Papers (Archive)

In a recent published work we proposed a technique to recover the absolute phase maps of two fringe patterns with different spatial frequencies. It is demonstrated that a number of selected frequency pairs can be used for the proposed approach, but the published work did not provide a guideline for frequency selection. In addition, the performance of the proposed technique in terms of its anti-noise capability is not addressed. In this paper, the rules for selecting the two frequencies are presented based on theoretical analysis of the proposed technique. Also, when the two frequencies are given, the anti-noise capability of …


Surface Diffusion Flow Near Spheres, Glen Wheeler Jan 2012

Surface Diffusion Flow Near Spheres, Glen Wheeler

Faculty of Informatics - Papers (Archive)

We consider closed immersed hypersurfaces evolving by surface diffusion flow, and perform an analysis based on local and global integral estimates. First we show that a properly immersed stationary (ΔH ≡ 0) hypersurface in R3 or R4 with restricted growth of the curvature at infinity and small total tracefree curvature must be an embedded union of umbilic hypersurfaces. Then we prove for surfaces that if the L2 norm of the tracefree curvature is globally initially small it is monotonic nonincreasing along the flow.We also derive pointwise estimates for all derivatives of the curvature assuming that its L …


Fault Analysis Of The Katan Family Of Block Ciphers, Shekh Faisal Abdul-Latip, Mohammad Reza Reyhanitabar, Willy Susilo, Jennifer Seberry Jan 2012

Fault Analysis Of The Katan Family Of Block Ciphers, Shekh Faisal Abdul-Latip, Mohammad Reza Reyhanitabar, Willy Susilo, Jennifer Seberry

Faculty of Informatics - Papers (Archive)

In this paper, we investigate security of the KATAN family of block ciphers against differential fault attacks. KATAN consists of three variants with 32, 48 and 64-bit block sizes, called KATAN32, KATAN48 and KATAN64, respectively. All three variants have the same key length of 80 bits. We assume a single-bit fault injection model where the adversary is supposed to be able to corrupt a single random bit of the internal state of the cipher and this fault induction process can be repeated (by resetting the cipher); i.e., the faults are transient rather than permanent. First, we show how to identify …


Estimating Variance Components And Predicting Breeding Values For Eventing Disciplines And Grades In Sport Horses, I D. Stewart, I.M S. White, Arthur R. Gilmour, R Thompson, J A. Woolliams, S Brotherstone Jan 2012

Estimating Variance Components And Predicting Breeding Values For Eventing Disciplines And Grades In Sport Horses, I D. Stewart, I.M S. White, Arthur R. Gilmour, R Thompson, J A. Woolliams, S Brotherstone

Faculty of Informatics - Papers (Archive)

Eventing competitions in Great Britain (GB) comprise three disciplines, each split into four grades, yielding 12 discipline-grade traits. As there is a demand for tools to estimate (co)variance matrices with a large number of traits, the aim of this work was to investigate different methods to produce large (co)variance matrices using GB eventing data. Data from 1999 to 2008 were used and penalty points were converted to normal scores. A sire model was utilised to estimate fixed effects of gender, age and class, and random effects of sire, horse and rider. Three methods were used to estimate (co)variance matrices. Method …


A Polarized Adaptive Schedule Generation Scheme For The Resource-Constrained Project Scheduling Problem, Reza Zamani Jan 2012

A Polarized Adaptive Schedule Generation Scheme For The Resource-Constrained Project Scheduling Problem, Reza Zamani

Faculty of Informatics - Papers (Archive)

This paper presents a hybrid schedule generation scheme for solving the resource-constrained project scheduling problem. The scheme, which is called the Polarized Adaptive Scheduling Scheme (PASS), can operate in a spectrum between two poles, namely the parallel and serial schedule generation schemes. A polarizer parameter in the range between zero and one indicates how similarly the PASS behaves like each of its two poles. The presented hybrid is incorporated into a novel genetic algorithm that never degenerates, resulting in an effective self-adaptive procedure. The key point of this genetic algorithm is the embedding of the polarizer parameter as a gene …


Homology For Higher-Rank Graphs And Twisted C*-Algebras, Alex Kumjian, David Pask, Aidan Sims Jan 2012

Homology For Higher-Rank Graphs And Twisted C*-Algebras, Alex Kumjian, David Pask, Aidan Sims

Faculty of Informatics - Papers (Archive)

We introduce a homology theory for k-graphs and explore its fundamental properties. We establish connections with algebraic topology by showing that the homology of a k-graph coincides with the homology of its topological realisation as described by Kaliszewski et al. We exhibit combinatorial versions of a number of standard topological constructions, and show that they are compatible, from a homological point of view, with their topological counterparts. We show how to twist the C*-algebra of a k-graph by a T-valued 2-cocycle and demonstrate that examples include all noncommutative tori. In the appendices, we construct a cubical set …


Privacy Enhanced Data Outsourcing In The Cloud, Miao Zhou, Yi Mu, Willy Susilo, Jun Yan, Liju Dong Jan 2012

Privacy Enhanced Data Outsourcing In The Cloud, Miao Zhou, Yi Mu, Willy Susilo, Jun Yan, Liju Dong

Faculty of Informatics - Papers (Archive)

How to secure outsourcing data in cloud computing is a challenging problem, since a cloud environment cannot been considered to be trusted. The situation becomes even more challenging when outsourced data sources in a cloud environment are managed by multiple outsourcers who hold different access rights. In this paper, we introduce an efficient and novel tree-based key management scheme that allows a data source to be accessed by multiple parties who hold different rights. We ensure that the database remains secure, while some selected data sources can be securely shared with other authorized parties.


On Formalizing Inter-Process Relationships, Tri A. Kurniawan, Aditya K. Ghose, Lam-Son Le, Hoa Khanh Dam Jan 2012

On Formalizing Inter-Process Relationships, Tri A. Kurniawan, Aditya K. Ghose, Lam-Son Le, Hoa Khanh Dam

Faculty of Informatics - Papers (Archive)

Most medium to large organizations support large collections of process designs, often stored in business process repositories. These processes are often inter-dependent. Managing such large collections of processes is not a trivial task. We argue that formalizing and establishing inter-process relationships play a critical role in that task leading to a machinery approach in the process repository management. We consider and propose three kinds of such relationships, namely part-whole, inter-operation and generalization-specialization, including their formal definitions, permitting us to develop a machinery approach. Analysis of the relationships relies on the semantically effects annotated process model in BPMN. This paper presents …


Positive Semidefinite Metric Learning Using Boosting-Like Algorithms, Chunhua Shen, Junae Kim, Lei Wang, Anton Van Den Hengel Jan 2012

Positive Semidefinite Metric Learning Using Boosting-Like Algorithms, Chunhua Shen, Junae Kim, Lei Wang, Anton Van Den Hengel

Faculty of Informatics - Papers (Archive)

The success of many machine learning and pattern recognition methods relies heavily upon the identification of an appropriate distance metric on the input data. It is often beneficial to learn such a metric from the input training data, instead of using a default one such as the Euclidean distance. In this work, we propose a boosting-based technique, termed BOOSTMETRIC, for learning a quadratic Mahalanobis distance metric. Learning a valid Mahalanobis distance metric requires enforcing the constraint that the matrix parameter to the metric remains positive semidefinite. Semidefinite programming is often used to enforce this constraint, but does not scale well …


Convex Hypersurfaces With Pinched Principal Curvatures And Flow Of Convex Hypersurfaces By High Powers Of Curvature, Ben Andrews, James Mccoy Jan 2012

Convex Hypersurfaces With Pinched Principal Curvatures And Flow Of Convex Hypersurfaces By High Powers Of Curvature, Ben Andrews, James Mccoy

Faculty of Informatics - Papers (Archive)

We consider convex hypersurfaces for which the ratio of principal curvatures at each point is bounded by a function of the maximum principal curvature with limit 1 at infinity. We prove that the ratio of circumradius to inradius is bounded by a function of the circumradius with limit 1 at zero. We apply this result to the motion of hypersurfaces by arbitrary speeds which are smooth homogeneous functions of the principal curvatures of degree greater than one. For smooth, strictly convex initial hypersurfaces with ratio of principal curvatures sufficiently close to one at each point, we prove that solutions remain …


A New Efficient Optimistic Fair Exchange Protocol Without Random Oracles, Qiong Huang, Guomin Yang, Duncan S Wong, Willy Susilo Jan 2012

A New Efficient Optimistic Fair Exchange Protocol Without Random Oracles, Qiong Huang, Guomin Yang, Duncan S Wong, Willy Susilo

Faculty of Informatics - Papers (Archive)

Optimistic fair exchange (OFE) is a kind of protocols to solve the problem of fair exchange between two parties. Most of the previous work on this topic are provably secure in the random oracle model. In this work, we propose a new construction of OFE from another cryptographic primitive, called time capsule signature. The construction is efficient and brings almost no overhead other than the primitive itself. The security of our new construction is based on that of the underlying primitive without relying on the random oracle heuristic. Applying our generic construction to the time capsule signature scheme recently proposed …


An Eigenvalue Approach To Evaluating Minors For Weighing Matrices W(N,N-1), Anna Karapiperi, Marilena Mitrouli, Michael G. Neubauer, Jennifer Seberry Jan 2012

An Eigenvalue Approach To Evaluating Minors For Weighing Matrices W(N,N-1), Anna Karapiperi, Marilena Mitrouli, Michael G. Neubauer, Jennifer Seberry

Faculty of Informatics - Papers (Archive)

In the present paper we concentrate our study on the evaluation of minors for weighing matrices W(n,n-1). Theoretical proofs concerning their minors up to the order of (n-4) x (n-4) are derived introducing an eigenvalue approach. A general theorem specifying the analytical form of any (n-l) x (n-l) minor is developed. An application to the growth problem for weighing matrices is given.


Reaction Attack On Outsourced Computing With Fully Homomorphic Encryption Schemes, Zhenfei Zhang, Thomas Plantard, Willy Susilo Jan 2012

Reaction Attack On Outsourced Computing With Fully Homomorphic Encryption Schemes, Zhenfei Zhang, Thomas Plantard, Willy Susilo

Faculty of Informatics - Papers (Archive)

Outsourced computations enable more efficient solutions towards practical problems that require major computations. Nevertheless, users’ privacy remains as a major challenge, as the service provider can access users’ data freely. It has been shown that fully homomorphic encryption schemes might be the perfect solution, as it allows one party to process users’ data homomorphically, without the necessity of knowing the corresponding secret keys. In this paper, we show a reaction attack against full homomorphic schemes, when they are used for securing outsourced computation. Essentially, our attack is based on the users’ reaction towards the output generated by the cloud. Our …


Wavelet-Based Resampling Techniques, Richard D. Kenderdine Jan 2012

Wavelet-Based Resampling Techniques, Richard D. Kenderdine

Faculty of Informatics - Papers (Archive)

Resampling methods were first developed in the late 1970s with the aim of obtaining estimates of the error in a statistic calculated from a sample. A necessary restriction was that the observations in the sample had to be independent, and various procedures have since been proposed to adapt the methods to dependent observations. Wavelet transforms that permit data to be analysed from a frequency or time viewpoint simultaneously have also been developed over a similar period. In simple terms, a wavelet transform produces coeffcients that are dierences between adjacent averages over increasing scales, and it has been noted that these …


A Fundamental Analysis Of Continuous Flow Bioreactor And Membrane Reactor Models With Non-Competitive Product Inhibition. Iii. Linear Inhibition, Mark I. Nelson, Wei X. Lim Jan 2012

A Fundamental Analysis Of Continuous Flow Bioreactor And Membrane Reactor Models With Non-Competitive Product Inhibition. Iii. Linear Inhibition, Mark I. Nelson, Wei X. Lim

Faculty of Informatics - Papers (Archive)

The steady-state production of a product produced through the growth of microorganisms in a continuous flow bioreactor is presented. A generalised reactor model is used in which both the classic well-stirred bioreactor and the idealised membrane bioreactor are considered as special cases. The reaction is assumed to be governed by Monod growth kinetics subject to non-competitive product inhibition. Inhibition is modelled as a decreasing linear function of the product concentration with a finite cut-off. This reaction scheme is well documented in the literature, although a stability analysis of the governing equations has not previously been presented. The steady-state solutions for …


Multivariate Whole Genome Average Interval Mapping: Qtl Analysis For Multiple Traits And/Or Environments, Arunas P. Verbyla, Brian R. Cullis Jan 2012

Multivariate Whole Genome Average Interval Mapping: Qtl Analysis For Multiple Traits And/Or Environments, Arunas P. Verbyla, Brian R. Cullis

Faculty of Informatics - Papers (Archive)

A major aim in some plant-based studies is the determination of quantitative trait loci (QTL) for multiple traits or across multiple environments. Understanding these QTL by trait or QTL by environment interactions can be of great value to the plant breeder. A whole genome approach for the analysis of QTL is presented for such multivariate applications. The approach is an extension of whole genome average interval mapping in which all intervals on a linkage map are included in the analysis simultaneously. A random effects working model is proposed for the multivariate (trait or environment) QTL effects for each interval, with …