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Articles 1 - 17 of 17
Full-Text Articles in Physical Sciences and Mathematics
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 …