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- Professor Pascal Perez (2)
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- Associate Professor Kashem Muttaqi (1)
- Associate Professor Mark Nelson (1)
- Associate Professor Minjie Zhang (1)
- Associate Professor Peter Hyland (1)
- B. G. Jones (1)
- Deng-Ke Yang (1)
- Dr Arthur Gilmour (1)
- Dr Janusz Getta (1)
- Dr Jun Yan (1)
- Gordon Wallace (1)
- Heath Ecroyd (1)
- Karin Garrety (1)
- Oleg Lavrentovich (1)
- Professor Brian Cullis (1)
- Professor Song-Ping Zhu (1)
- Robin Selinger (1)
- Satyendra Kumar (1)
- Sugam Sharma (1)
Articles 1 - 26 of 26
Full-Text Articles in Physical Sciences and Mathematics
Towards Querying And Visualization Of Large Spatio-Temporal Databases, Sugam Sharma
Towards Querying And Visualization Of Large Spatio-Temporal Databases, Sugam Sharma
Sugam Sharma
In any database model, data analysis can be eased by extracting a smaller set of the data of interest, called subset, from the mammoth original dataset. Thus, a subset helps enhance the performance of a system by avoiding the iteration through the huge parental data in further analysis. A subset, its specification, or the formal process for its extraction can be complex. In the database community, subsets are extracted through SQL-like queries and through visualization in the Geographic Information System (GIS) community. Both are iterative processes. An SQL query can be a composition of subqueries. Each subquery can be seen …
Ordering And Self-Diffusion In The 1st Molecular Layer At A Liquid-Crystal Polymer Interface, G. P. Crawford, Deng-Ke Yang, S. Zumer, D. Finotello, J. William Doane
Ordering And Self-Diffusion In The 1st Molecular Layer At A Liquid-Crystal Polymer Interface, G. P. Crawford, Deng-Ke Yang, S. Zumer, D. Finotello, J. William Doane
Deng-Ke Yang
H-2 NMR of a liquid crystal confined to submicron cylindrical cavities, in a 17-K interval above the nematic-isotropic transition, reveals a weakly orientationally ordered molecular layer at the cavity wall governed by local interactions. The order (S0 = 0.02) is temperature independent so that a partial wetting is realized with no prewetting transition expected. A molecular exchange rate between the surface layer and the bulk is measured to be approximately 10(3) s-1. The coherence length measuring the order penetrating further into the cavity is described by alpha = 0.4 and xi-0 = 0.6 nm.
Monte Carlo Simulations Of Stable Point Defects In Hybrid Nematic Films, C. Chiccoli, Oleg Lavrentovich, P. Pasini, C. Zannoni
Monte Carlo Simulations Of Stable Point Defects In Hybrid Nematic Films, C. Chiccoli, Oleg Lavrentovich, P. Pasini, C. Zannoni
Oleg Lavrentovich
Monte Carlo (MC) simulations based exclusively on nearest-neighbor intermolecular interactions reveal the existence of stable long-range deformations and topological defects in a thin nematic film confined between two surfaces with antagonistic (normal and tangential) molecular orientations. Thus the MC technique allows one to describe a delicate balance of bulk elasticity and surface energy usually treated only with macroscopic theories.
Critical Behavior At The Nematic To Lamellar Phase Transitions: A Synchrotron X-Ray Scattering Study, S. T. Shin, J. D. Brock, Mark Sutton, J. D. Lister, Satyendra Kumar
Critical Behavior At The Nematic To Lamellar Phase Transitions: A Synchrotron X-Ray Scattering Study, S. T. Shin, J. D. Brock, Mark Sutton, J. D. Lister, Satyendra Kumar
Satyendra Kumar
The nematic (N) to lamellar (Lα) phase transition in binary mixtures of cesium-perfluoro-octanoate (CsPFO) and water has been studied by high-resolution synchrotron x-ray scattering at 46.6 weight % CsPFO. The longitudinal correlation length ξ∥ and the susceptibility σ associated with the lamellar phase fluctuations in the N phase, measured over three decades of reduced temperature, diverge with critical exponents ν∥=0.86±0.04 and γ=1.37±0.11, respectively. These results show that the N to Lα phase transition is quantitatively similar to the N to smectic-A phase transition of thermotropic liquid crystals with a wider nematic range.
Assessing Soil Remobilisation In Catchments Using A 137 Cs-Sediment Hillslope Model, Ava D. Simms, Colin D. Woodroffe, Brian G. Jones, Henk Heijnis, Jennifer Harrison, Rob Mann
Assessing Soil Remobilisation In Catchments Using A 137 Cs-Sediment Hillslope Model, Ava D. Simms, Colin D. Woodroffe, Brian G. Jones, Henk Heijnis, Jennifer Harrison, Rob Mann
B. G. Jones
Soil redistribution studies are important, especially in water supply catchments, because the rate at which denudation is occurring has implications for offsite water quality. However, the extent to which soil is redistributed within the landscape can be difficult to determine. This challenge can be overcome using fallout caesium-137 (137Cs). This paper describes the rates of soil loss and remobilisation in two sub-catchments within the Sydney Basin region, namely Kembla and Kentish Creeks, which drain to the Cordeaux reservoir. The total inventories of 137Cs in catchment soils were determined, a 137Cs-regression equation and a theoretical diffusion and migration model were used …
A Numerical Model For Multiphase Flow Based On The Gmpps Formulation, Part I Kinematics, Song-Ping Zhu, Frank Bierbrauer
A Numerical Model For Multiphase Flow Based On The Gmpps Formulation, Part I Kinematics, Song-Ping Zhu, Frank Bierbrauer
Professor Song-Ping Zhu
The CFD modeling of two dimensional multiphase ows is a useful tool in industry, although accurate modeling itself remains a difficult task. One of the difficulties is to track the complicated topological deformations of the interfaces between di erent phases. This paper describes a marker-particle method designed to track fluid interfaces for fluid ows of at least three phases. The interface-tracking scheme presented in this paper is the first part of a series of papers presenting our complete model based on a one-field Godunov marker-particle projection scheme (GMPPS). In this part, we shall focus on the presentation of the interface-tracking …
Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook
Levetiracetam-Loaded Biodegradable Polymer Implants In The Tetanus Toxin Model Of Temporal Lobe Epilepsy In Rats, Amy J. Halliday, Toni E. Campbell, Timothy S. Nelson, Karen J. Mclean, Gordon G. Wallace, Mark J. Cook
Gordon Wallace
Approximately one-third of people with epilepsy receive insufficient benefit from currently available anticonvulsant medication, and some evidence suggests that this may be due to a lack of effective penetration into brain parenchyma. The current study investigated the ability of biodegradable polymer implants loaded with levetiracetam to ameliorate seizures following implantation above the motor cortex in the tetanus toxin model of temporal lobe epilepsy in rats. The implants led to significantly shorter seizures and a trend towards fewer seizures for up to 1 week. The results of this study indicate that drug-eluting polymer implants represent a promising evolving treatment option for …
Morphology Transition In Lipid Vesicles Due To In-Plane Order And Topological Defects, Linda S. Hirst, Adam Ossowski, Matthew Fraser, Jun Geng, Jonathan Selinger, Robin Selinger
Morphology Transition In Lipid Vesicles Due To In-Plane Order And Topological Defects, Linda S. Hirst, Adam Ossowski, Matthew Fraser, Jun Geng, Jonathan Selinger, Robin Selinger
Robin Selinger
Complex morphologies in lipid membranes typically arise due to chemical heterogeneity, but in the tilted gel phase, complex shapes can form spontaneously even in a membrane containing only a single lipid component. We explore this phenomenon via experiments and coarse-grained simulations on giant unilamellar vesicles of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine. When cooled from the untilted L-alpha liquid-crystalline phase into the L-beta, tilted gel phase, vesicles deform from smooth spheres to disordered, highly crumpled shapes. We propose that this shape evolution is driven by nucleation of complex membrane microstructure with topological defects in the tilt orientation that induce nonuniform membrane curvature. Coarse-grained simulations demonstrate …
A Mathematical Model For The Biological Treatment Of Industrial Wastewaters In A Cascade Of Four Reactors, Annette L. Worthy, Mark I. Nelson, Rubayyi Turki Alqahtani
A Mathematical Model For The Biological Treatment Of Industrial Wastewaters In A Cascade Of Four Reactors, Annette L. Worthy, Mark I. Nelson, Rubayyi Turki Alqahtani
Associate Professor Annette Worthy
Many industrial processes, particularly in the food industry, produce slurriesor wastewaters containing high concentrations of biodegradable organicmaterials. Before these contaminated wastewaters can be dischargedthe concentration of these pollutants must be reduced. A method which has beenextensively employed to remove biodegradable organic matter is biologicaltreatment. In this process the wastewater (or slurry) is passed through abioreactor containing biomass which grows through consumption of thepollutants.The industrial treatment of wastewaters typically employs a reactor cascade.In a reactor cascade of n reactors the effluent stream from the ith reactor inthe cascade acts as the feed stream for the (i+1)th reactor, i.e. the nextreactor. The …
Autoignition Of Hydrocarbons In A Batch Reactor: Analysis Of A Reduced Model, Mark I. Nelson, E Balakrishnan
Autoignition Of Hydrocarbons In A Batch Reactor: Analysis Of A Reduced Model, Mark I. Nelson, E Balakrishnan
Associate Professor Mark Nelson
n the late 1960s Gray and Yang developed the first reduced kinetic model for the oxidation of hydrocarbon fuels that qualitatively described many features observed experimentally. Since then a number of reduced kinetic models have been proposed in the literature. In this contribution we analyse the steady-state behaviour of one such scheme. The chemical component of the model contains four chemical species undergoing six reactions. By making a pool-chemical approximation this system is reduced to three coupled non-linear differential equations: a temperature equation and equations for two reactive chemical intermediates. It is shown that any steady-state solution of this model …
Estimation In A Multiplicative Mixed Model Involving A Genetic Relationship Matrix, Alison M. Kelly, Brian R. Cullis, Arthur R. Gilmour, John A. Eccleston, Robin Thompson
Estimation In A Multiplicative Mixed Model Involving A Genetic Relationship Matrix, Alison M. Kelly, Brian R. Cullis, Arthur R. Gilmour, John A. Eccleston, Robin Thompson
Dr Arthur Gilmour
Genetic models partitioning additive and non-additive genetic effects for populations tested in replicated multi-environment trials (METs) in a plant breeding program have recently been presented in the literature. For these data, the variance model involves the direct product of a large numerator relationship matrix A, and a complex structure for the genotype by environment interaction effects, generally of a factor analytic (FA) form. With MET data, we expect a high correlation in genotype rankings between environments, leading to non-positive definite covariance matrices. Estimation methods for reduced rank models have been derived for the FA formulation with independent genotypes, and we …
Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim
Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim
Associate Professor Minjie Zhang
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 …
Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu
Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu
Dr Jun Yan
The goal of federated identity management is to allow principals, such as identities and attributes, to be shared across trust boundaries based on established policies. Since current Single Sign-On (SSO) mechanism excessively relies on the specifications of Circle of Trust (CoT), the need for service collaboration from different domains is being addressed on CoT. For the motivating issue of the cross-domain SSO mechanism, we need an emergent dynamic trust list for calculating the trust parties, thus, the CoT specifications require an initial effort on enrolling members automatically to adapt to the dynamic open environment. In this paper, we propose a …
A Preliminary Investigation Of Complex Adaptive Systems As A Model For Explaining Organisational Change Caused By The Introduction Of Health Information Systems, Kieren Diment, Ping Yu, Karin Garrety
A Preliminary Investigation Of Complex Adaptive Systems As A Model For Explaining Organisational Change Caused By The Introduction Of Health Information Systems, Kieren Diment, Ping Yu, Karin Garrety
Karin Garrety
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 …
A Spatial Agent-Based Model To Explore Scenarios Of Adaptation To Climate Change In An Alpine Tourism Destination, Stefano Balbi, Pascal Perez, Carlo Giupponi
A Spatial Agent-Based Model To Explore Scenarios Of Adaptation To Climate Change In An Alpine Tourism Destination, Stefano Balbi, Pascal Perez, Carlo Giupponi
Professor Pascal Perez
A vast body of literature suggests that the European Alpine region may be one of the most sensitive to climate change impacts. Adaptation to climate change of Alpine socioecosystems is increasingly becoming an issue of interest for the scientific community while the people of the Alps are often unaware of or simply ignore the problem. ClimAlpTour is a European research project of the Alpine Space Programme, bringing together institutions and scholars from all countries of the Alpine arch, in view of dealing with the expected decrease in snow and ice cover, which may lead to a rethinking of tourism development …
An Ontology-Based Simulation Model Exploring The Social Contexts Of Psychostimulant Use Among Young Australians, Pascal Perez, Anne Dray, Paul Dietze, David Moore, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan L. Hudson, Lisa Maher, Gabriele Bammer
An Ontology-Based Simulation Model Exploring The Social Contexts Of Psychostimulant Use Among Young Australians, Pascal Perez, Anne Dray, Paul Dietze, David Moore, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan L. Hudson, Lisa Maher, Gabriele Bammer
Professor Pascal Perez
The principal anthropogenic factors driving reef degradation have been known for years, if not decades. Overfishing, sedimentation and nutrient loads are just some of the key impacts of human activities in and around reef communities. Therefore, the future of reefs does not rely on generating new knowledge, but rather on implementing and integrating the knowledge we already have. This will require creating effective links between researchers, managers and communities to promote mutual learning, negotiation and collaborative action for reef management. Combining agent-based models and role-play games, through a technique known as Companion Modelling (ComMod), creates a dynamic and interactive setting …
Implementation Of Artificial Intelligence Technique To Model Arc Furnace Responses, A.M.O Haruni, Michael Negnevitsky, M.E Haque, Kashem Muttaqi
Implementation Of Artificial Intelligence Technique To Model Arc Furnace Responses, A.M.O Haruni, Michael Negnevitsky, M.E Haque, Kashem Muttaqi
Associate Professor Kashem Muttaqi
Random variations of the bus voltage and power consumption of an electric arc furnace (EAF) have a significant impact on power generation equipment, transient stability of the power system network and power quality to other interconnected loads. Therefore, an accurate representation of the load's dynamic behaviour under various system disturbances is very important. This paper presents an arc furnace model using adaptive neuro-fuzzy inference system (ANFIS) in order to capture random, non-linear and time-varying load pattern of an arc furnace. To evaluate the performance of the proposed model, several case studies are presented where the outputs of the proposed model …
Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu
Dynamic Trust Model For Federated Identity Management, Hao Gao, Jun Yan, Yi Mu
Professor Yi Mu
The goal of federated identity management is to allow principals, such as identities and attributes, to be shared across trust boundaries based on established policies. Since current Single Sign-On (SSO) mechanism excessively relies on the specifications of Circle of Trust (CoT), the need for service collaboration from different domains is being addressed on CoT. For the motivating issue of the cross-domain SSO mechanism, we need an emergent dynamic trust list for calculating the trust parties, thus, the CoT specifications require an initial effort on enrolling members automatically to adapt to the dynamic open environment. In this paper, we propose a …
Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim
Pbtrust: A Priority-Based Trust Model For Service Selection In General Service-Oriented Environments, Xing Su, Minjie Zhang, Yi Mu, Kwang Mong Sim
Professor Yi Mu
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 …
Combining Outputs From The North American Regional Climate Change Assessment Program By Using A Bayesian Hierarchical Model, Emily L. Kang, Noel Cressie, Stephan R. Sain
Combining Outputs From The North American Regional Climate Change Assessment Program By Using A Bayesian Hierarchical Model, Emily L. Kang, Noel Cressie, Stephan R. Sain
Professor Noel Cressie
We investigate the 20-year-average boreal winter temperatures generated by an ensemble of six regional climate models (RCMs) in phase I of the North American Regional Climate Change Assessment Program. We use the long-run average (20-year integration) to smooth out variability and to capture the climate properties from the RCM outputs. We find that, although the RCMs capture the large-scale climate variation from coast to coast and from south to north similarly, their outputs can differ substantially in some regions. We propose a Bayesian hierarchical model to synthesize information from the ensemble of RCMs, and we construct a consensus climate signal …
Hierarchical Model Building, Fitting, And Checking: A Behind-The-Scenes Look At A Bayesian Analysis Of Arsenic Exposure Pathways, Peter F. Craigmile, Catherine A. Calder, Hongfei Li, Rajib Paul, Noel Cressie
Hierarchical Model Building, Fitting, And Checking: A Behind-The-Scenes Look At A Bayesian Analysis Of Arsenic Exposure Pathways, Peter F. Craigmile, Catherine A. Calder, Hongfei Li, Rajib Paul, Noel Cressie
Professor Noel Cressie
In this article, we present a behind-the-scenes look at a Bayesian hierarchical analysis of pathways of exposure to arsenic (a toxic heavy metal) using the Phase I National Human Exposure Assessment Survey carried out in Arizona. Our analysis combines individual-level personal exposure measurements (biomarker and environmental media) with water, soil, and air observations from the ambient environment. We include details of our model-building exercise that involved a combination of exploratory data analysis and substantive knowledge in exposure science. Then we present our strategies for model fitting, which involved piecing together components of the hierarchical model in a systematic fashion to …
An Assessment Tool For E-Government System Performance: A Citizen-Centric Model, Shatha A. Al-Haddad, Peter Hyland, Geoffrey Hubona
An Assessment Tool For E-Government System Performance: A Citizen-Centric Model, Shatha A. Al-Haddad, Peter Hyland, Geoffrey Hubona
Associate Professor Peter Hyland
Governments worldwide have, increasingly, implemented e-government initiatives for their potential significant benefits; among which, delivering better services to citizens through increasing citizens' convenience, satisfaction, and independence; and saving their time, effort, and cost. Achieving each benefit is an objective to these governments and fulfilling each objective is considered a critical success factors. Hence, governments need to assess the extent to which they were able to obtain their preset goals. This study merely focuses on the citizens' perspective of the evaluation. However, the literature seems to lack studies that propose such a sufficient evaluation tool that has been reliably validated. Therefore, …
Application Of Semistructured Data Model To The Implementation Of Semantic Content-Based Video Retrieval System, Lilac A. E. Al-Safadi, Janusz R. Getta
Application Of Semistructured Data Model To The Implementation Of Semantic Content-Based Video Retrieval System, Lilac A. E. Al-Safadi, Janusz R. Getta
Dr Janusz Getta
Semantic indexing of a video document is a process that performs the identification of elementary and complex semantic units in the indexed document in order to create a semantic index defined as a mapping of semantic units into the sequences of video frames. Semantic content-based video retrieval system is a software system that uses a semantic index built over a collection of video documents to retrieve the sequences of video frames that satisfy the given conditions. This work introduces a new multilevel view of data for the semantic content-based video retrieval systems. At the topmost level, we define an abstract …
Estimation In A Multiplicative Mixed Model Involving A Genetic Relationship Matrix, Alison M. Kelly, Brian R. Cullis, Arthur R. Gilmour, John A. Eccleston, Robin Thompson
Estimation In A Multiplicative Mixed Model Involving A Genetic Relationship Matrix, Alison M. Kelly, Brian R. Cullis, Arthur R. Gilmour, John A. Eccleston, Robin Thompson
Professor Brian Cullis
Genetic models partitioning additive and non-additive genetic effects for populations tested in replicated multi-environment trials (METs) in a plant breeding program have recently been presented in the literature. For these data, the variance model involves the direct product of a large numerator relationship matrix A, and a complex structure for the genotype by environment interaction effects, generally of a factor analytic (FA) form. With MET data, we expect a high correlation in genotype rankings between environments, leading to non-positive definite covariance matrices. Estimation methods for reduced rank models have been derived for the FA formulation with independent genotypes, and we …
The Gleamviz Computational Tool, A Publicly Available Software To Explore Realistic Epidemic Spreading Scenarios At The Global Scale, Wouter Van Den Broeck, Corrado Gioannini, Bruno Goncalves, Marco Quaggiotto, Vittoria Colizza, Alessandro Vespignani
The Gleamviz Computational Tool, A Publicly Available Software To Explore Realistic Epidemic Spreading Scenarios At The Global Scale, Wouter Van Den Broeck, Corrado Gioannini, Bruno Goncalves, Marco Quaggiotto, Vittoria Colizza, Alessandro Vespignani
Alessandro Vespignani
Background: Computational models play an increasingly important role in the assessment and control of public health crises, as demonstrated during the 2009 H1N1 influenza pandemic. Much research has been done in recent years in the development of sophisticated data-driven models for realistic computer-based simulations of infectious disease spreading. However, only a few computational tools are presently available for assessing scenarios, predicting epidemic evolutions, and managing health emergencies that can benefit a broad audience of users including policy makers and health institutions. Results: We present "GLEaMviz", a publicly available software system that simulates the spread of emerging human-to-human infectious diseases across …
Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal
Model For Amorphous Aggregation Processes, Samual Stranks, Heath Ecroyd, Steve Van Sluyter, Elizabeth J. Waters, John A. Carver, Lorenz Von Smekal
Heath Ecroyd
The amorphous aggregation of proteins is associated with many phenomena, ranging from the formation of protein wine haze to the development of cataract in the eye lens and the precipitation of recombinant proteins during their expression and purification. While much literature exists describing models for linear protein aggregation, such as amyloid fibril formation, there are few reports of models which address amorphous aggregation. Here, we propose a model to describe the amorphous aggregation of proteins which is also more widely applicable to other situations where a similar process occurs, such as in the formation of colloids and nanoclusters. As first …