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Full-Text Articles in Physical Sciences and Mathematics
Applying A Novel Combination Of Techniques To Develop A Predictive Model For Diabetes Complications, Mohsen Sangi, Khin Than Win, Farid Shirvani, Mohammad-Reza Namazi-Rad, Nagesh Shukla
Applying A Novel Combination Of Techniques To Develop A Predictive Model For Diabetes Complications, Mohsen Sangi, Khin Than Win, Farid Shirvani, Mohammad-Reza Namazi-Rad, Nagesh Shukla
Nagesh Shukla
No abstract provided.
Synthesis And Hydrolytic Evaluation Of Acid-Labile Imine-Linked Cytoxic Isatin Model Systems, Lidia Matesic, Julie Locke, Kara Perrow, Marie Ranson, John Bremner, Danielle Skropeta
Synthesis And Hydrolytic Evaluation Of Acid-Labile Imine-Linked Cytoxic Isatin Model Systems, Lidia Matesic, Julie Locke, Kara Perrow, Marie Ranson, John Bremner, Danielle Skropeta
Danielle Skropeta
In this study a series of isatin-based, pH-sensitive aryl imine derivatives with differing aromatic substituents and substitution patterns were synthesised and their acid-catalysed hydrolysis evaluated. These derivatives were functionalised at the C3 carbonyl group of a potent N-substituted isatin cytotoxin and were stable at physiological pH but readily cleaved at pH 4.5. Observed rates of hydrolysis for the embedded imine-acid moiety were in the order para-phenylpropionic acid>phenylacetic acid (para>meta)>benzoic acid (meta>para). The ability to fine-tune hydrolysis rates in this way has potential implications for optimising imine linked, tumour targeting cytotoxin-protein conjugates
Analysis Of A Chemostat Model With Variable Yield Coefficient: Contois Kinetics., Rubayyi Alqahtani, Mark Nelson, Annette Worthy
Analysis Of A Chemostat Model With Variable Yield Coefficient: Contois Kinetics., Rubayyi Alqahtani, Mark Nelson, Annette Worthy
Associate Professor Annette Worthy
Food processing wastewaters and slurries typically contain high concentrations of biodegradable organic matter. Before the wastewater can be discharged, the pollutant concentration must be reduced. One way to achieve this is by using a biological species (biomass) that consumes the organic matter (substrate). We investigate an unstructured kinetic model for a bioreactor with a variable yield coefficient, taking into account the death rate of the microorganisms. The growth rate is given by a Contois expression, which is often used to model the growth of biomass in wastewaters containing biodegradable organic materials. The analysis shows that the system has natural oscillations …
Analysis Of A Chemostat Model With Variable Yield Coefficient: Contois Kinetics., Rubayyi Alqahtani, Mark Nelson, Annette Worthy
Analysis Of A Chemostat Model With Variable Yield Coefficient: Contois Kinetics., Rubayyi Alqahtani, Mark Nelson, Annette Worthy
Associate Professor Mark Nelson
Food processing wastewaters and slurries typically contain high concentrations of biodegradable organic matter. Before the wastewater can be discharged, the pollutant concentration must be reduced. One way to achieve this is by using a biological species (biomass) that consumes the organic matter (substrate). We investigate an unstructured kinetic model for a bioreactor with a variable yield coefficient, taking into account the death rate of the microorganisms. The growth rate is given by a Contois expression, which is often used to model the growth of biomass in wastewaters containing biodegradable organic materials. The analysis shows that the system has natural oscillations …
A Mathematical Model For The Biological Treatment Of Industrial Wastewaters In A Cascade Of Four Reactors, Annette Worthy, Mark Nelson, Rubayyi Turki Alqahtani
A Mathematical Model For The Biological Treatment Of Industrial Wastewaters In A Cascade Of Four Reactors, Annette Worthy, Mark Nelson, Rubayyi Turki Alqahtani
Associate Professor Mark Nelson
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 …
A Two Dimensional, Reaction-Diffusion Model Of Compost Piles, T Luangwilai, H Sidhu, M Nelson
A Two Dimensional, Reaction-Diffusion Model Of Compost Piles, T Luangwilai, H Sidhu, M Nelson
Associate Professor Mark Nelson
We consider the self heating process in a two dimensional spatially dependent model of a compost pile which incorporates terms that account for self heating due to both biological and oxidation mechanisms. As moisture is a crucial factor in both the degradation process and spontaneous ignition within a compost pile, this model consists of four mass-balance equations, namely, energy, oxygen, vapour and liquid water concentrations. Analyses are undertaken for different initial water contents within the compost pile. We show that when the water content is too low, the reaction is almost negligible; whereas when it is too high, the reaction …
A Spatially Uniform Model Of Oxidative Self-Heating In Compost Piles, Mark Nelson, Xiao Dong Chen, Harvinder Sidhu
A Spatially Uniform Model Of Oxidative Self-Heating In Compost Piles, Mark Nelson, Xiao Dong Chen, Harvinder Sidhu
Associate Professor Mark Nelson
In this paper we model the thermal behaviour of compost heaps in the presence of micro-organism undergoing oxidative exothermic reactions. For simplicity we consider a spatially uniform model in which oxidative reactions of the cellulosic components is ignored. We use singularity theory to investigate the generic properties of the model. We show that there are two generic steady-state diagrams including one in which the temperature-response curve is the standard S-shaped curve familiar from combustion problems. Such a steady-state diagram contains an elevated temperature branch, which is the feature of practical interest in facilities such as industrial compost heaps and municipal …
Enhanced Learner Model For Adaptive Mobile Learning, Ahmed Alhmouz, Jun Shen, Jun Yan, Rami Al-Hmouz
Enhanced Learner Model For Adaptive Mobile Learning, Ahmed Alhmouz, Jun Shen, Jun Yan, Rami Al-Hmouz
Dr Jun Yan
Personalisation and learner modelling are becoming more important in the area of mobile learning applications, taking into consideration learners' interests, preferences and contextual information. Students nowadays are able to learn anywhere and at any time. Mobile learning application content is one of several factors within various contexts that play an important role in the success of the adaptation process. The vast amount of data involved in any successful adaptation process creates complexity and poses serious challenges. This paper focuses on how to model the learner and all possible contexts in an extensible way that can be used for personalisation in …
An Extended Dual Concern Model For Partner Selection In Multi-Agent Systems, Minjie Zhang, Jun Yan, Fenghui Ren
An Extended Dual Concern Model For Partner Selection In Multi-Agent Systems, Minjie Zhang, Jun Yan, Fenghui Ren
Dr Jun Yan
No abstract provided.
Improved Certificateless Signature Scheme Provably Secure In The Standard Model, Yong Yu, Yi Mu, Guilin Wang, Q Xia, B Yang
Improved Certificateless Signature Scheme Provably Secure In The Standard Model, Yong Yu, Yi Mu, Guilin Wang, Q Xia, B Yang
Dr Guilin Wang
Certificateless cryptography shares many features of identity-based cryptography and partially solves the problem of key escrow. Three certificateless signature schemes without random oracles were found in the literature. However, all the schemes suffer from some common drawbacks. First, by obtaining a signature on a message and replacing the public key of a signer, an adversary can forge valid signatures on the same message under the replaced public key. Secondly, all the schemes require a relatively large size of public parameters. The authors propose a new certificateless signature scheme, which exhibits an improvement on the existing schemes. Compared with the previous …
What Has My Classifier Learned? Visualizing The Classification Rules Of Bag-Of-Feature Model By Support Region Detection, Lingqiao Liu, Lei Wang
What Has My Classifier Learned? Visualizing The Classification Rules Of Bag-Of-Feature Model By Support Region Detection, Lingqiao Liu, Lei Wang
Dr Lei Wang
In the past decade, the bag-of-feature model has established itself as the state-of-the-art method in various visual classification tasks. Despite its simplicity and high performance, it normally works as a black box and the classification rule is not transparent to users. However, to better understand the classification process, it is favorable to look into the black box to see how an image is recognized. To fill this gap, we developed a tool called Restricted Support Region Set (RSRS) Detection which can be utilized to visualize the image regions that are critical to the classification decision. More specifically, we define the …
Enhanced Learner Model For Adaptive Mobile Learning, Ahmed Alhmouz, Jun Shen, Jun Yan, Rami Al-Hmouz
Enhanced Learner Model For Adaptive Mobile Learning, Ahmed Alhmouz, Jun Shen, Jun Yan, Rami Al-Hmouz
Dr Jun Shen
Personalisation and learner modelling are becoming more important in the area of mobile learning applications, taking into consideration learners' interests, preferences and contextual information. Students nowadays are able to learn anywhere and at any time. Mobile learning application content is one of several factors within various contexts that play an important role in the success of the adaptation process. The vast amount of data involved in any successful adaptation process creates complexity and poses serious challenges. This paper focuses on how to model the learner and all possible contexts in an extensible way that can be used for personalisation in …
Bilateral Single-Issue Negotiation Model Considering Nonlinear Utility And Time Constraint, Fenghui Ren, Minjie Zhang, John Fulcher
Bilateral Single-Issue Negotiation Model Considering Nonlinear Utility And Time Constraint, Fenghui Ren, Minjie Zhang, John Fulcher
Dr Fenghui Ren
Bilateral single-issue negotiation is studied a lot by researchers as a fundamental research issue in agent negotiation. During a negotiation with time constraint, a negotiation decision function is usually predefined by negotiators to express their expectations on negotiation outcomes in different rounds. By combining the negotiation decision function with negotiators' utility functions, offers can be generated accurately and efficiently to satisfy negotiators expectations in each round. However, such a negotiation procedure may not work well when negotiators' utility functions are nonlinear. For example, if negotiators' utility functions are non-monotonic, negotiators may find several offers that come with the same utility; …
Simamph: An Agent-Based Simulation Model For Exploring The Use Of Psychostimulants And Related Harm Amongst Young Australians, Pascal Perez, Anne Dray, David Moore, Paul Dietze, Gabriele Bammer, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan Hudson, Lisa Maher
Simamph: An Agent-Based Simulation Model For Exploring The Use Of Psychostimulants And Related Harm Amongst Young Australians, Pascal Perez, Anne Dray, David Moore, Paul Dietze, Gabriele Bammer, Rebecca Jenkinson, Christine Siokou, Rachael Green, Susan Hudson, Lisa Maher
Professor Pascal Perez
Background: Computer simulations provide a useful tool for bringing together diverse sources of information in order to increase understanding of the complex aetiology of drug use and related harm, and to inform the development of effective policies. In this paper, we describe SimAmph, an agent-based simulation model for exploring how individual perceptions, peer influences and subcultural settings shape the use of psychostimulants and related harm amongst young Australians. Methods: We present the conceptual architecture underpinning SimAmph, the assumptions we made in building it, the outcomes of sensitivity analysis of key model parameters and the results obtained when we modelled a …
Simreef: An Agent-Based Model To Address Coastal Management Issues In The Yucatan Peninsula, Mexico, Pascal Perez, A Dray, Deborah Cleland, Jesus Ernesto Arias-Gonzalez
Simreef: An Agent-Based Model To Address Coastal Management Issues In The Yucatan Peninsula, Mexico, Pascal Perez, A Dray, Deborah Cleland, Jesus Ernesto Arias-Gonzalez
Professor Pascal Perez
The northernmost part of the Mesoamerican Barrier Reef (MBR) runs along the eastern Yucatan peninsula (Mexico). Over two decades, sprawling coastal tourism development and over-exploitation of marine resources have considerably reduced fringing reef’s ecological functions. SimReef is an interactive model designed to better understand the interactions between regional and local drivers strongly influencing the health of coral reefs. SimReef’s development follows a collective design approach and an inductive process whereby dynamics are represented by data-driven relationships. Experts and stakeholders participate to the designing phase in order to help calibrating the model and to support a consensual validation of the results.
Are Drug Detection Dogs And Mass-Media Campaigns Likely To Be Effective Policy Responses To Psychostimulant Use And Related Harm? Results From An Agent-Based Simulation Model, David Moore, Lisa Maher, Christine Siokou, Rachael Green, Anne Dray, Rebecca Jenkinson, Susan Hudson, Gabriele Bammer, Pascal Perez, Paul Dietze
Are Drug Detection Dogs And Mass-Media Campaigns Likely To Be Effective Policy Responses To Psychostimulant Use And Related Harm? Results From An Agent-Based Simulation Model, David Moore, Lisa Maher, Christine Siokou, Rachael Green, Anne Dray, Rebecca Jenkinson, Susan Hudson, Gabriele Bammer, Pascal Perez, Paul Dietze
Professor Pascal Perez
Background Agent-based simulation models can be used to explore the impact of policy and practice on drug use and related consequences. In a linked paper (Perez et al., 2011), we described SimAmph, an agent-based simulation model for exploring the use of psychostimulants and related harm amongst young Australians. Methods In this paper, we use the model to simulate the impact of two policy scenarios on engagement in drug use and experience of drug-related harm: (i) the use of passive-alert detection (PAD) dogs by police at public venues and (ii) the introduction of a mass-media drug prevention campaign. Results The findings …
Assessment Of Length Distributions Between Non-Coding And Coding Sequences Amongst Two Model Organisms, Ren Zhang, Rachel Caldwell, Yan-Xia Lin
Assessment Of Length Distributions Between Non-Coding And Coding Sequences Amongst Two Model Organisms, Ren Zhang, Rachel Caldwell, Yan-Xia Lin
Associate Professor Yan-Xia Lin
No abstract provided.
Model-Based Fuzzy Control For Buildings Installed With Magneto-Rheological Dampers, Haiping Du, Nong Zhang
Model-Based Fuzzy Control For Buildings Installed With Magneto-Rheological Dampers, Haiping Du, Nong Zhang
Dr Haiping Du
No abstract provided.
The Analysis Of Longitudinal Data Using Mixed Model L-Splines, S. Welham, Brian Cullis, M. Kenward, R Thompson
The Analysis Of Longitudinal Data Using Mixed Model L-Splines, S. Welham, Brian Cullis, M. Kenward, R Thompson
Professor Brian Cullis
L-splines are a large family of smoothing splines defined in terms of a linear differential operator. This article develops L-splines within the context of linear mixed models and uses the resulting mixed model L-spline to analyze longitudinal data from a grassland experiment. In the spirit of time-series analysis, a periodic mixed model L-spline is developed, which partitions data into a smooth periodic component plus smooth long-term trend.
A Comparison Of Mixed Model Splines For Curve Fitting, S Welham, Brian Cullis, M Kenward, R Thompson
A Comparison Of Mixed Model Splines For Curve Fitting, S Welham, Brian Cullis, M Kenward, R Thompson
Professor Brian Cullis
Three types of polynomial mixed model splines have been proposed: smoothing splines, Psplines and penalized splines using a truncated power function basis. The close connections between these models are demonstrated, showing that the default cubic form of the splines differs only in the penalty used. A general definition of the mixed model spline is given that includes general constraints and can be used to produce natural or periodic splines. The impact of different penalties is demonstrated by evaluation across a set of functions with specific features, and shows that the best penalty in terms of mean squared error of prediction …
A Networked Virtual Environment Communications Model Using Priority Updating, Yang-Wai Chow, Ronald Pose, Matthew Regan
A Networked Virtual Environment Communications Model Using Priority Updating, Yang-Wai Chow, Ronald Pose, Matthew Regan
Dr Yang-Wai Chow
Networked virtual environments have been used in a variety of applications ranging from military training simulations to collaborative teleconferencing, and have recently become increasingly popular in the field of entertainment especially in online gaming. As the size, distribution and number of participants of these virtual world systems increases, so do the demands placed on the limited networking resources. This has presented networked virtual environment system developers with the problem of having to design efficient network communication models in order to reduce the amount of network traffic and bandwidth utilization, while at the same time not compromising on the real-time interactive …
Model-Based Direct Estimation Of Small-Area Distributions, Nicola Salvati, Hukum Chandra, Ray Chambers
Model-Based Direct Estimation Of Small-Area Distributions, Nicola Salvati, Hukum Chandra, Ray Chambers
Dr Raymond Chambers
"Much of the small-area estimation literature focuses on population totals and means. However, users of survey data are often interested in the finite-population distribution of a survey variable and in the measures (e.g. medians, quartiles, percentiles) that characterize the shape of this distribution at the small-area level. In this paper we propose a model-based direct estimator (MBDE, Chandra and Chambers) of the small-area distribution function. The MBDE is defined as a weighted sum of sample data from the area of interest, with weights derived from the calibrated spline-based estimate of the finite-population distribution function introduced by Harms and Duchesne, under …
Small Area Estimation Using A Nonparametric Model-Based Direct Estimator, Raymond Chambers, Nicola Salvati, M. Giovanna Ranalli, Hukum Chandra
Small Area Estimation Using A Nonparametric Model-Based Direct Estimator, Raymond Chambers, Nicola Salvati, M. Giovanna Ranalli, Hukum Chandra
Dr Raymond Chambers
Nonparametric regression is widely used as a method of characterizing a non-linearrelationship between a variable of interest and a set of covariates. Practical application ofnonparametric regression methods in the field of small area estimation is fairly recent,and has so far focussed on the use of empirical best linear unbiased prediction under amodel that combines a penalized spline (p-spline) fit and random area effects. The conceptof model-based direct estimation is used to develop an alternative nonparametric approachto estimation of a small area mean. The suggested estimator is a weighted average of thesample values from the area, with weights derived from a …
Flexible Free-Standing Carbon Nanotube Films For Model Lithium-Ion Batteries, Jun Chen, Sau Yen Chew, See How Ng, Jiazhao Wang, Hua Liu, P Novak, F Krumeich, Shulei Chou
Flexible Free-Standing Carbon Nanotube Films For Model Lithium-Ion Batteries, Jun Chen, Sau Yen Chew, See How Ng, Jiazhao Wang, Hua Liu, P Novak, F Krumeich, Shulei Chou
Shulei Chou
No abstract provided.
Chemical Cross-Linking Of The Chloroplast Localized Small Heat-Shock Protein, Hsp21, And The Model Substrate Citrate Synthase, Emma Ahrman, W Lambert, Andrew Aquilina, C V Robinson, Cs Emanuelsson
Chemical Cross-Linking Of The Chloroplast Localized Small Heat-Shock Protein, Hsp21, And The Model Substrate Citrate Synthase, Emma Ahrman, W Lambert, Andrew Aquilina, C V Robinson, Cs Emanuelsson
J. A. Aquilina
The molecular mechanism whereby the small heat-shock protein (sHsp) chaperones interact with and prevent aggregation of other proteins is not fully understood. We have characterized the sHsp-substrate protein interaction at normal and increased temperatures utilizing a model substrate protein, citrate synthase (CS), widely used in chaperone assays, and a dodecameric plant sHsp, Hsp21, by chemical cross-linking with 3,3'-Dithiobis[sulfosuccinimidylpropionate] (DTSSP) and mass spectrometric peptide mapping. In the absence of CS, the cross-linker captured Hsp21 in dodecameric form, even at increased temperature (47 degrees C). In the presence of equimolar amounts of CS, no Hsp21 dodecamer was captured, indicating a substrate-induced Hsp21 …