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Complex Adaptive Systems As A Model For Evaluating Organisational Change Caused By The Introduction Of Health Information Systems, Kieren Diment Mr, Ping Yu, K. Garrety Aug 2009

Complex Adaptive Systems As A Model For Evaluating Organisational Change Caused By The Introduction Of Health Information Systems, Kieren Diment Mr, Ping Yu, K. Garrety

Faculty of Informatics - Papers (Archive)

This paper documents the preliminary development of a framework for evaluating organisational change processes during the implementation of an electronic nursing documentation system in residential aged care facilities. It starts with a brief outline of organisational change processes. This is followed by a more detailed exposition of the principles underlying complex adaptive systems (CAS) theory, where we explain how mathematical concepts can be used to illuminate qualitative research approaches. Finally we present some preliminary findings on the facilitators and barriers for the introduction of the electronic documentation system, explained with reference to the CAS theory, based on analysis of interviews …


Rejoinder, Peter Craigmile, Catherine Caldert, Hongfei Li, Rajib Paul, Noel Cressie Jan 2009

Rejoinder, Peter Craigmile, Catherine Caldert, Hongfei Li, Rajib Paul, Noel Cressie

Faculty of Informatics - Papers (Archive)

We agree with Schmidt that it is essential that researchers from many diverse areas have access to affordable, but still trustworthy, software. In this research project, substantial effort went into preparing datasets. Much of the data came from different government agencies, with databases arranged in multiple formats, often including variables that were not immediately relevant to our scientific pursuits. In our work on this project, the use of SAS was essential to producing clean datasets.


Accounting For Uncertainty In Ecological Analysis: The Strengths And Limitations Of Hierarchical Statistical Modeling, Noel Cressie, Catherine Calder, James Clark, Jay Ver Hoef, Christopher Wikle Jan 2009

Accounting For Uncertainty In Ecological Analysis: The Strengths And Limitations Of Hierarchical Statistical Modeling, Noel Cressie, Catherine Calder, James Clark, Jay Ver Hoef, Christopher Wikle

Faculty of Informatics - Papers (Archive)

Analyses of ecological data should account for the uncertainty in the process(es) that generated the data. However, accounting for these uncertainties is a difficult task, since ecology is known for its complexity. Measurement and/or process errors are often the only sources of uncertainty modeled when addressing complex ecological problems, yet analyses should also account for uncertainty in sampling design, in model specification, in parameters governing the specified model, and in initial and boundary conditions. Only then can we be confident in the scientific inferences and forecasts made from an analysis. Probability and statistics provide a framework that accounts for multiple …


Measuring End-Users' Opinions For Establishing A User-Centred Electronic Health Record (Ehr) System From The Perspective Of Nurses, Yung-Yu Su, Khin Than Win, John Fulcher, Herng-Chia Chiu Jan 2009

Measuring End-Users' Opinions For Establishing A User-Centred Electronic Health Record (Ehr) System From The Perspective Of Nurses, Yung-Yu Su, Khin Than Win, John Fulcher, Herng-Chia Chiu

Faculty of Informatics - Papers (Archive)

Establishing an acceptable user-centred electronic health record (EHR) system is a challenging task for healthcare providers due to the need for such systems to meet the requirements of its user population. Concerned nurses are the main end-users of EHR systems. Based on knowledge of evidence-based management (EBM) and the issues (goals and methods) of Health Information Systems (HIS) evaluation, this research was performed in four regional teaching hospitals by adopting a quantitative approach research design to perform “goal-based evaluation” research. The results of Path Analysis indicated that 17 of 21 hypotheses were accepted in this study. In addition, the results …


Application Of Microsimulation To The Modelling Of Terrorist Attacks, Ian Piper, Daniel Keep, Tony Green, Ivy Zhang Jan 2009

Application Of Microsimulation To The Modelling Of Terrorist Attacks, Ian Piper, Daniel Keep, Tony Green, Ivy Zhang

Faculty of Informatics - Papers (Archive)

In this paper, a novel approach to behavioural modelling is presented with reference to biological infection spread in communities. Its potential application to various terrorist-related scenarios is discussed in relation to attack point simulation and interdiction simulation.


Explicit Connections Between Longitudinal Data Analysis And Kernel Machines, N D. Pearce, M. P. Wand Jan 2009

Explicit Connections Between Longitudinal Data Analysis And Kernel Machines, N D. Pearce, M. P. Wand

Faculty of Informatics - Papers (Archive)

Two areas of research - longitudinal data analysis and kernel machines - have large, but mostly distinct, literatures. This article shows explicitly that both fields have much in common with each other. In particular, many popular longitudinal data fitting procedures are special types of kernel machines. These connections have the potential to provide fruitful cross-fertilization between longitudinal data analytic and kernel machine methodology.


Semiparametric Regression During 2003-2007, David Ruppert, M. P. Wand, Raymond J. Carroll Jan 2009

Semiparametric Regression During 2003-2007, David Ruppert, M. P. Wand, Raymond J. Carroll

Faculty of Informatics - Papers (Archive)

Semiparametric regression is a fusion between parametric regression and nonparametric regression that integrates low-rank penalized splines, mixed model and hierarchical Bayesian methodology - thus allowing more streamlined handling of longitudinal and spatial correlation. We review progress in the field over the five-year period between 2003 and 2007. We find semiparametric regression to be a vibrant field with substantial involvement and activity, continual enhancement and widespread application.


Diffusive Growth Of Fullerenes And Carbon Nanotubes, J E. Bunder, James M. Hill Jan 2009

Diffusive Growth Of Fullerenes And Carbon Nanotubes, J E. Bunder, James M. Hill

Faculty of Informatics - Papers (Archive)

The video of a growing fullerene within a carbon nanotube, initiated by a tungsten catalyst, provides a dramatic realization of a complex nanoscale process. While there may be many detailed models which can account for this growth, we propose one of the simplest possible models which is consistent with the major observed features of the growth process. In particular, we assume that the fullerene is immersed in a carbon vapor environment, and that the growth occurs as a consequence of the diffusion of the carbon vapor into the fullerene. Moreover, we assume that the classical diffusion equation applies in the …


Optimal Exercise Price Of American Options Near Expiry, W.-T. Chen, Song-Ping Zhu Jan 2009

Optimal Exercise Price Of American Options Near Expiry, W.-T. Chen, Song-Ping Zhu

Faculty of Informatics - Papers (Archive)

This paper investigates American puts on a dividend-paying underlying whose volatility is a function of both time and underlying asset price. The asymptotic behaviour of the critical price near expiry is deduced by means of singular perturbation methods. It turns out that if the underlying dividend is greater than the risk-free interest rate, the behaviour of the critical price is parabolic, otherwise an extra logarithmic factor appears, which is similar to the constant volatility case. The results of this paper complement numerical approaches used to calculate the option values and the optimal exercise price at times that are not close …


Relative Survival After Hospitalisation For Hip Fracture In Older People In New South Wales, Australia, Diane Hindmarsh, Andrew Hayen, Caroline Finch, Jacqueline Ct Close Jan 2009

Relative Survival After Hospitalisation For Hip Fracture In Older People In New South Wales, Australia, Diane Hindmarsh, Andrew Hayen, Caroline Finch, Jacqueline Ct Close

Faculty of Informatics - Papers (Archive)

Survival after hospitalisation for hip fracture by age group and sex relative to survival in the general population was assessed in people aged 65+. Men had double the risk of death compared with women to 1 year, but age effects lasted only to 3 months. Clinical outcomes need to be improved.We assessed the relative survival of hospitalised fall-related hip fracture patients aged 65+ years leaving hospital in New South Wales, Australia, between July 2000 and December 2003.We carried out a population-based study of all hospital separations for NSW residents with a principal diagnosis of hip fracture (ICD-10-AM S72.0 to S72.2) …


Sampling For Subpopulations In Household Surveys With Application To Maori And Pacific Sampling, Robert Graham Clark, Michael Doherty, Angela Forbes, Robert Templeton Jan 2009

Sampling For Subpopulations In Household Surveys With Application To Maori And Pacific Sampling, Robert Graham Clark, Michael Doherty, Angela Forbes, Robert Templeton

Faculty of Informatics - Papers (Archive)

Many NZ national household surveys have a requirement to produce statistics with adequate precision both for the whole of NZ and for important subpopulations, particularly the Maori and Pacific populations. General population surveys which make no special provision for these groups would generally not achieve sufficient precision for Maori and Pacific estimates when these are of particular interest. Kalton and Anderson (1986) described a range of strategies for sampling subpopulations, where the aim is only to produce statistics about the subpopulation and not national statistics. The purpose of this Official Statistics Research fund project is to extend the methods of …


A Conceptlink Graph For Text Structure Mining, Rowena Chau, Ah Chung Tsoi, Markus Hagenbuchner, Vincent Lee Jan 2009

A Conceptlink Graph For Text Structure Mining, Rowena Chau, Ah Chung Tsoi, Markus Hagenbuchner, Vincent Lee

Faculty of Informatics - Papers (Archive)

Most text mining methods are based on representing documents using a vector space model, commonly known as a bag of word model, where each document is modeled as a linear vector representing the occurrence of independent words in the text corpus. It is well known that using this vector-based representation, important information, such as semantic relationship among concepts, is lost. This paper proposes a novel text representation model called ConceptLink graph. The ConceptLink graph does not only represent the content of the document, but also captures some of its underlying semantic structure in terms of the relationships among concepts. The …


The Graph Neural Network Model, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini Jan 2009

The Graph Neural Network Model, Franco Scarselli, Marco Gori, Ah Chung Tsoi, Markus Hagenbuchner, Gabriele Monfardini

Faculty of Informatics - Papers (Archive)

Many underlying relationships among data in several areas of science and engineering, e.g., computer vision, molecular chemistry, molecular biology, pattern recognition, and data mining, can be represented in terms of graphs. In this paper, we propose a new neural network model, called graph neural network (GNN) model, that extends existing neural network methods for processing the data represented in graph domains. This GNN model, which can directly process most of the practically useful types of graphs, e.g., acyclic, cyclic, directed, and undirected, implements a function tau(G,n) isin IRm that maps a graph G and one of its nodes n …


A Hospital Based Dynamic Platform Workflow Management, Nantika Prinyapol, Joshua P. Fan, S. Lau Jan 2009

A Hospital Based Dynamic Platform Workflow Management, Nantika Prinyapol, Joshua P. Fan, S. Lau

Faculty of Informatics - Papers (Archive)

In this paper, we propose the use of dynamic compilation of web services to support workflow management in a hospital setting. Web services related to work practices belong to an organization that have been designed, built and stored in a web services repository. These web services can be shared with multiple functional units within the organization via the intranet or the Internet. The workflow of a health scenario will be presented. Work practice services that were selected will be compiled logically and optimally using the proposed dynamic compilation platform. The final outcome is presented as a web application. The web …


Construction Of Amicable Orthogonal Designs Of Quaternions, Ying Zhao, Jennifer Seberry, Tianbing Xia, Beata J. Wysocki, Tadeusz A. Wysocki Jan 2009

Construction Of Amicable Orthogonal Designs Of Quaternions, Ying Zhao, Jennifer Seberry, Tianbing Xia, Beata J. Wysocki, Tadeusz A. Wysocki

Faculty of Informatics - Papers (Archive)

This paper introduces some construction methods for amicable orthogonal designs over the real and quaternion domains which have been explored for code design before. The proposed construction methods generate a large number of amicable orthogonal designs of quaternions can be used to construct restricted quaternion orthogonal designs which can be applied to orthogonal space-time polarization block codes for wireless communications.


Customizable Data Exchange Based On Web Service, Jun Xu, Gang Xiao, Jiawei Lu, Qianhui Liang, Jun Shen Jan 2009

Customizable Data Exchange Based On Web Service, Jun Xu, Gang Xiao, Jiawei Lu, Qianhui Liang, Jun Shen

Faculty of Informatics - Papers (Archive)

In this paper, we propose a method of customizable data exchange based on the service-oriented application environment. We highlight the data exchange model of this method, analyze the components and specific functions of the exchange platform and data exchange node in the model, and finally expound the operation principle and specific implementation of customizable data exchange. We demonstrate this is an efficient way to overcome the shortcomings of the original, single and fixed data exchange mode.


Distance Geometry In Quasihypermetric Spaces. I, Peter Nickolas, Reinhard Wolf Jan 2009

Distance Geometry In Quasihypermetric Spaces. I, Peter Nickolas, Reinhard Wolf

Faculty of Informatics - Papers (Archive)

Let (X,d) be a compact metric space and let (X) denote the space of all finite signed Borel measures on X. Define I:(X)→ by ...

and set M(X)=sup I(μ), where μ ranges over the collection of signed measures in (X) of total mass 1.

The metric space (X,d) is quasihypermetric if for all n, all α1,…,αn satisfying ∑ i=1nαi=0 and all x1,…,xnX, …


Coverings Of Skew Products And Crossed Products By Coactions, David A. Pask, John Quigg, Aidan Sims Jan 2009

Coverings Of Skew Products And Crossed Products By Coactions, David A. Pask, John Quigg, Aidan Sims

Faculty of Informatics - Papers (Archive)

Consider a projective limit G of finite groups Gn. Fix a compatible family δn of coactions of the Gn on a C*-algebra A. From this data we obtain a coaction δ of G on A. We show that the coaction crossed product of A by δ is isomorphic to a direct limit of the coaction crossed products of A by the δn. If A=C*(Λ) for some k-graph Λ, and if the coactions δn correspond to skew-products of Λ, then we can say more. We …


Pairwise: A Time Hopping Medium Access Control Protocol For Wireless Sensor Networks, Kwan-Wu Chin Jan 2009

Pairwise: A Time Hopping Medium Access Control Protocol For Wireless Sensor Networks, Kwan-Wu Chin

Faculty of Informatics - Papers (Archive)

The availability of low cost, multifunctional embedded devices have become ubiquitous due to their wide ranging application that includes monitoring Radio Frequency Identification (RFID) tagged objects to ambient conditions such as temperature and humidity. Also, these devices can be equipped with a camera and then deployed in hostile environments. A key characteristic of these devices is that they can communicate wirelessly and form an ad-hoc, Wireless Sensor Network (WSN). Devices in a WSN then collaboratively monitor environment factors or objects, and forward data back to one or more central nodes. A key challenge in WSN is ensuring nodes operate in …


Noncommutative Manifolds From Graph And K-Graph C*-Algebras, David A. Pask, Adam Rennie, Aidan Sims Jan 2009

Noncommutative Manifolds From Graph And K-Graph C*-Algebras, David A. Pask, Adam Rennie, Aidan Sims

Faculty of Informatics - Papers (Archive)

In [PRen] we constructed smooth (1,∞)-summable semfinite spectral triples for graph algebras with a faithful trace, and in [PRS] we constructed (k,∞)-summable semifinite spectral triples for k-graph algebras. In this paper we identify classes of graphs and k-graphs which satisfy a version of Connes’ conditions for noncommutative manifolds.


Faml: A Generic Metamodel For Mas Development, Ghassan Beydoun, Graham Low, Brian Henderson-Sellers, Haralambos Mouratidis, Jorge J. Gomez-Sanz, Juan Pavon, Cesar Gonzalez-Perez Jan 2009

Faml: A Generic Metamodel For Mas Development, Ghassan Beydoun, Graham Low, Brian Henderson-Sellers, Haralambos Mouratidis, Jorge J. Gomez-Sanz, Juan Pavon, Cesar Gonzalez-Perez

Faculty of Informatics - Papers (Archive)

In some areas of software engineering research, there are several metamodels claiming to capture the main issues. Though it is profitable to have variety at the beginning of a research field, after some time, the diversity of metamodels becomes an obstacle, for instance to the sharing of results between research groups. To reach consensus and unification of existing metamodels, metamodel-driven software language engineering can be applied. This paper illustrates an application of software language engineering in the agent-oriented software engineering research domain. Here, we introduce a relatively generic agent-oriented metamodel whose suitability for supporting modeling language development is demonstrated by …


3d Spatial Interaction With The Wii Remote For Head-Mounted Display Virtual Reality, Yang-Wai Chow Jan 2009

3d Spatial Interaction With The Wii Remote For Head-Mounted Display Virtual Reality, Yang-Wai Chow

Faculty of Informatics - Papers (Archive)

This research investigates the design of a low-cost 3D spatial interaction approach using the Wii Remote for immersive Head-Mounted Display (HMD) virtual reality. Current virtual reality applications that incorporate the Wii Remote are either desktop virtual reality applications or systems that use large screen displays. However, the requirements for an HMD virtual reality system differ from such systems. This is mainly because in HMD virtual reality, the display screen does not remain at a fixed location. The user views the virtual environment through display screens that are in front of the user’s eyes and when the user moves his/her head, …


Analysis Of An Immobilised Enzyme Reactor With Catalysts Activation, Mark Nelson, Harvinder Sidhu, Soji Adesina Jan 2009

Analysis Of An Immobilised Enzyme Reactor With Catalysts Activation, Mark Nelson, Harvinder Sidhu, Soji Adesina

Faculty of Informatics - Papers (Archive)

We investigate the behavior of a reaction described by Michaelis-Menten kinetics in an immobilized enzyme reactor (IER). The IER is treated as a well stirred flow reactor, in which the immobilized bounded and unbounded enzyme species are constrained to remain within the reaction vessel. The product species leaves the IER in the reactor outflow. Before the substrate can react with the enzyme, the enzyme must first be activated by absorption of an activator. We use steady state analysis to identify the best operating conditions or the reactor. To this end, we show that the concentration of product is maximized at …


Identity-Based Universal Designated Verifier Signature Proof System, Xiaofeng Chen, Guomin Chen, Fangguo Zhang, Baodian Wei, Yi Mu Jan 2009

Identity-Based Universal Designated Verifier Signature Proof System, Xiaofeng Chen, Guomin Chen, Fangguo Zhang, Baodian Wei, Yi Mu

Faculty of Informatics - Papers (Archive)

The notion of Universal Designated Verifier Signature (UDVS), introduced by Steinfeld et al. in Asiacrypt 2003, allows any holder of a signature to convince any designated verifier that the signer indeed generated the signature without revealing the signature itself, while the verifier cannot transfer the proof to convince anyone else of this fact. Such signature schemes can protect the privacy of signature holders and have applications in certification systems. Very recently, as pointed out by Baek et al. in Asiacrypt 2005, one significant inconvenience of all existing UDVS schemes is that they require the designated verifier to create a public …


Controller Design For Time-Delay Systems Using Genetic Algorithms, Haiping Du, Nong Zhang Jan 2009

Controller Design For Time-Delay Systems Using Genetic Algorithms, Haiping Du, Nong Zhang

Faculty of Informatics - Papers (Archive)

This paper presents a new approach to design controllers for time-delay systems by using genetical gorithms (GAs) together with the solvability of linear matrix inequalities (LMIs). Both of the state- feedback controller and the static output feedback controller can be designed with this approach. It is confirmed by numerical examples that this approach achieves less conservative results than previouslyexisting methods on the given examples.


Certificate-Based Signatures Revisited, Wei Wu, Yi Mu, Willy Susilo, Xinyi Huang Jan 2009

Certificate-Based Signatures Revisited, Wei Wu, Yi Mu, Willy Susilo, Xinyi Huang

Faculty of Informatics - Papers (Archive)

Certificate-based encryption was introduced in Eurocrypt'03 to solve the certificate management problem in public key encryption. Recently, this idea was extended to certificate-based signatures. Several new schemes and security models of certificate-based signatures have been proposed. In this paper, we first take a closer look at the certificate-based signature by comparing it with digital signatures in other popular public key systems. We introduce a new security model of certificate-based signature, which defines several new types of adversaries against certificate-based signatures, along with the security model of certificate-based signatures against them. The new model is clearer and more elaborated compared with …


Optical Feedback Self-Mixing Interferometry With A Large Feedback Factor C: Behavior Studies, Yanguang Yu, Jiangtao Xi, Joe F. Chicharo, Thierry Bosch Jan 2009

Optical Feedback Self-Mixing Interferometry With A Large Feedback Factor C: Behavior Studies, Yanguang Yu, Jiangtao Xi, Joe F. Chicharo, Thierry Bosch

Faculty of Informatics - Papers (Archive)

This paper studies the behavior of optical feedback self-mixing interferometric (OFSMI) systems, where the semiconductor lasers operate at a single mode (perturbed external cavity mode) with a large optical feedback factor C. Based on analysis of the spectral linewidth associated with all the possible lasing modes at different C values, a set of mode jumping rules are proposed following the minimum linewidth mode competition principle proposed in . According to the rules, the C factor can be classified into different regions, on which an OFSMI system will exhibit distinct phenomena. In particular, for the same amount of displacement associated …


Robust Controller Design For Vehicle Semi-Active Suspensions With Electroheologocal Dampers, Haiping Du, Nong Zhang Jan 2009

Robust Controller Design For Vehicle Semi-Active Suspensions With Electroheologocal Dampers, Haiping Du, Nong Zhang

Faculty of Informatics - Papers (Archive)

This paper presents a robust control approach for semi-active suspensions with electrorheological (ER) dampers considering system parameter uncertainties and control input constraint. By representing the suspension with parameter uncertainties in a polytopic form and applying a norm-bounded approach to handle control input constraint, the design of this controller is derived as solving a finite number of linear matrix inequalities (LMIs) with optimised H performance on ride comfort. Numerical simulations on a quarter-car suspension with an ER damper are performed to validate the effectiveness of the proposed approach. The obtained results show that the designed controller can achieve good suspension …


Using Social Networking And Collections To Enable Video Semantics Acquisition, S. J. Davis, Christian H. Ritz, I. Burnett Jan 2009

Using Social Networking And Collections To Enable Video Semantics Acquisition, S. J. Davis, Christian H. Ritz, I. Burnett

Faculty of Informatics - Papers (Archive)

Video content both professionally and user generated is now a prime driver of Internet usage and activity; Simultaneously, the Internet has seen the rise of social networking sites and activity. This paper brings together video content and social networking to solve the problem of gathering metadata which describes user interaction, usage and opinion of video content. The paper explores mechanisms by which implied and explicit semantics can be garnered from users interacting with media within social networks. This leads to the gathering of individual user interaction metadata which is then aggregated to form semantic metadata for a given video. The …


Improving Software Testing Cost-Effectiveness Through Dynamic Partitioning, Zhiquan Zhou, Arnaldo Sinaga, Lei Zhao, Willy Susilo, Kai-Yuan Cai Jan 2009

Improving Software Testing Cost-Effectiveness Through Dynamic Partitioning, Zhiquan Zhou, Arnaldo Sinaga, Lei Zhao, Willy Susilo, Kai-Yuan Cai

Faculty of Informatics - Papers (Archive)

We present a dynamic partitioning strategy that selects test cases using online feedback information. The presented strategy differs from conventional approaches. Firstly, the partitioning is carried out online rather than off-line. Secondly, the partitioning is not based on program code or specifications; instead, it is simply based on the fail or pass information of previously executed test cases and, hence, can be implemented in the absence of the source code or specification of the program under test. The cost-effectiveness of the proposed strategy has been empirically investigated with three programs, namely SPACE, SED, and GREP. The results show that the …