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Faculty of Informatics - Papers (Archive)

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Articles 121 - 150 of 2013

Full-Text Articles in Physical Sciences and Mathematics

3d Face Recognition Based On A Modified Icp Method, Kankan Zhao, Jiangtao Xi, Yanguang Yu, Joe F. Chicharo Jan 2011

3d Face Recognition Based On A Modified Icp Method, Kankan Zhao, Jiangtao Xi, Yanguang Yu, Joe F. Chicharo

Faculty of Informatics - Papers (Archive)

3D face recognition technique has gained much more attention recently, and it is widely used in security system, identification system, and access control system, etc. The core technique in 3D face recognition is to find out the corresponding points in different 3D face images. The classic partial Iterative Closest Point (ICP) method is iteratively align the two point sets based on repetitively calculate the closest points as the corresponding points in each iteration. After several iterations, the corresponding points can be obtained accurately. However, if two 3D face images with different scale are from the same person, the classic partial …

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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 Jan 2011

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

Faculty of Informatics - Papers (Archive)

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 …

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Application Of Microsimulation To Disease Transmission And Control, A Green, Y Zhang, I Piper, Daniel Keep Jan 2011

Application Of Microsimulation To Disease Transmission And Control, A Green, Y Zhang, I Piper, Daniel Keep

Faculty of Informatics - Papers (Archive)

In this paper, we present an extension of our novel microsimulation technique, as applied to biological infection spread, to estimate the underlying causal parameters driving an infectious process. The underlying simulation framework, Simulacron, was developed in order to understand the development and course of, response to and recovery from single and multiple threats on community populations. Such threats include a range of natural (such as disease spread in communities, fire, flood etc.) and manmade events (such as terrorism, including the use of biological agents, money laundering, smuggling as well as accidents etc.). These threats can cause serious disruption to modern …

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Propagation Of Optical Spatial Solitary Waves In Bias-Free Nematic-Liquid-Crystal Cells, Antonmaria A. Minzoni, Luke W. Sciberras, Noel F. Smyth, Annette L. Worthy Jan 2011

Propagation Of Optical Spatial Solitary Waves In Bias-Free Nematic-Liquid-Crystal Cells, Antonmaria A. Minzoni, Luke W. Sciberras, Noel F. Smyth, Annette L. Worthy

Faculty of Informatics - Papers (Archive)

The propagation of a bulk optical solitary wave in a rectangular cell filled with a nematic liquid crystal—a nematicon—is mathematically modelled. In order to overcome the Freédricksz threshold the cell walls are rubbed to pretilt the nematic. A modulation theory, based on a Lagrangian formulation, is developed for the (2+1)-dimensional propagation of the solitary wave beam down the cell. This modulation theory is based on two different formulations of the director distribution. The relative advantages and disadvantages of these two methods are discussed. A previously unexplored method based on images is found to possess significant advantages. Excellent agreement with full …

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Using A Multi-Experimental Approach To Assess The Fate Of Angled-And-Released Yellowtail Kingfish (Seriola Lalandi), Lachlan W. Roberts, Paul A. Butcher, Matt K. Broadhurst, Brian R. Cullis Jan 2011

Using A Multi-Experimental Approach To Assess The Fate Of Angled-And-Released Yellowtail Kingfish (Seriola Lalandi), Lachlan W. Roberts, Paul A. Butcher, Matt K. Broadhurst, Brian R. Cullis

Faculty of Informatics - Papers (Archive)

Yellowtail kingfish (Seriola lalandi) are angled throughout their global distribution and released in large numbers under the unsubstantiatedassumption of few impacts. The validity of this supposition was tested for southeastern Australian stocks. In all, 54 fishwere angled and released into cages with 36 controls and monitored for 5 d. Of the angled fish, 15% died, mostly as a consequenceof gill-hooking and the associated physiological and mechanical damage. A biotelemetry experiment was then performed to determineif cutting the line on gill-hooked fish could improve their post-release fate. The attachment of transmitters was validated in anaquarium experiment before 12 jaw- and 10 …

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Optimization Of Task Processing Schedules In Distributed Information Systems, Janusz R. Getta Jan 2011

Optimization Of Task Processing Schedules In Distributed Information Systems, Janusz R. Getta

Faculty of Informatics - Papers (Archive)

The performance of data processing in distributed information systems strongly depends on theefficient scheduling of the applications that access data at the remote sites. This work assumes atypical model of distributed information system where a central site is connected to a number ofremote and highly autonomous remote sites. An application started by a user at a central site isdecomposed into several data processing tasks to be independently processed at the remote sites.The objective of this work is to find a method for optimization of task processing schedules at acentral site. We define an abstract model of data and a system …

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Exploring Teleconsultation Acceptance: A Comparison Study Between Emergency And Non-Emergency Setting, Nurazean Maarop, Khin Than Win, Maslin Masrom, Sukdershan Singh Hazara Singh Jan 2011

Exploring Teleconsultation Acceptance: A Comparison Study Between Emergency And Non-Emergency Setting, Nurazean Maarop, Khin Than Win, Maslin Masrom, Sukdershan Singh Hazara Singh

Faculty of Informatics - Papers (Archive)

This research explores the acceptance of teleconsultation technology among healthcare providers of public hospitals in Malaysia. Primary constructs from Davis' Technology Acceptance Model (TAM) are employed for this purpose. Further, the study also compares the level of user acceptance between emergency and non-emergency setting. This study is based on descriptive statistic and correlation analysis served as preliminary exploration of the acceptance of the technology understudy. The study reports a high level of acceptance of teleconsultation technology in both emergency and non-emergency settings thus exhibits no significant difference in acceptance the acceptance of teleconsultation technology for both respective settings. The results …

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Initial Values In Estimation Procedures For State Space Models (Ssms), Raed Alzghool, Yan-Xia Lin Jan 2011

Initial Values In Estimation Procedures For State Space Models (Ssms), Raed Alzghool, Yan-Xia Lin

Faculty of Informatics - Papers (Archive)

In this paper, we will focus on State Space Models(SSMs), especially the stochastic volatility model, and lookfor a standard approach for assigning initial values in theQuasi-Likelihood (QL) and Asymptotic Quasi-Likelhood (AQL)estimation procedures.

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A Spectral-Collocation Method For Pricing Perpetual American Puts With Stochastic Volatility, Song-Ping Zhu, Wenting Chen Jan 2011

A Spectral-Collocation Method For Pricing Perpetual American Puts With Stochastic Volatility, Song-Ping Zhu, Wenting Chen

Faculty of Informatics - Papers (Archive)

Based on the Legendre pseudospectral method, we propose a numerical treatment for pricing perpetual American put option with stochastic volatility. In this simple approach, a nonlinear algebraic equation system is first derived, and then solved by the Gauss–Newton algorithm. The convergence of the current scheme is ensured by constructing a test example similar to the original problem, and comparing the numerical option prices with those produced by the classical Projected SOR (PSOR) method. The results of our numerical experiments suggest that the proposed scheme is both accurate and efficient, since the spectral accuracy can be easily achieved within a small …

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Threshold Anonymous Announcement In Vanets, Guilin Wang, L Chen, S. L. Ng Jan 2011

Threshold Anonymous Announcement In Vanets, Guilin Wang, L Chen, S. L. Ng

Faculty of Informatics - Papers (Archive)

Vehicular ad hoc networks (VANETs) allow wireless communications between vehicles without the aid of a central server. Reliable exchanges of information about road and traffic conditions allow a safer and more comfortable travelling environment. However, such profusion of information may allow unscrupulous parties to violate user privacy. On the other hand, a degree of auditability is desired for law enforcement and maintenance purposes. In this paper we propose a Threshold Anonymous Announcement service using direct anonymous attestation and one-time anonymous authentication to simultaneously achieve the seemingly contradictory goals of reliability, privacy and auditability.

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Efficient Strong Designated Verifier Signature Schemes Without Random Oracle Or With Non-Delegatability, Q Huang, G Yang, D S Wong, Willy Susilo Jan 2011

Efficient Strong Designated Verifier Signature Schemes Without Random Oracle Or With Non-Delegatability, Q Huang, G Yang, D S Wong, Willy Susilo

Faculty of Informatics - Papers (Archive)

Designated verifier signature (DVS) allows a signer to convince a designated verifier that a signature is generated by the signer without letting the verifier transfer the conviction to others, while the public can still tell that the signature must be generated by one of them. Strong DVS (SDVS) strengthens the latter part by restricting the public from tellingwhether the signature is generated by one of them or by someone else. In this paper, we propose two new SDVS schemes. Compared with existing SDVS schemes, the first new scheme has almost the same signature size and meanwhile, is proven secure in …

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Experimental Investigation Of The Vibration Characteristics Of A Magnetorheological Elastomer Sandwich Beam Under Non-Homogeneous Small Magnetic Fields, Guoliang Hu, Miao Guo, Weihua Li, Haiping Du, Gursel Alici Jan 2011

Experimental Investigation Of The Vibration Characteristics Of A Magnetorheological Elastomer Sandwich Beam Under Non-Homogeneous Small Magnetic Fields, Guoliang Hu, Miao Guo, Weihua Li, Haiping Du, Gursel Alici

Faculty of Informatics - Papers (Archive)

In this study, a magnetorheological elastomer (MRE) was manufactured and tested, and a MRE sandwich beam was also fabricated from a MRE between two thin aluminum layers. An experimental test rig was set up to investigate the vibration response of the MRE sandwich beam under a non-homogeneous magnetic field. The experimental results show that the first natural frequency of the MRE sandwich beam decreased as the magnetic field applied to the beam was moved from the clamped end of the beam to the free end of the beam. It is also noted that the MRE sandwich beam had the capability …

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Offline Programming For A Complex Welding System Using Delmia Automation, Joseph Polden, Zengxi Pan, Nathan P. Larkin, Stephen Van Duin, John Norrish Jan 2011

Offline Programming For A Complex Welding System Using Delmia Automation, Joseph Polden, Zengxi Pan, Nathan P. Larkin, Stephen Van Duin, John Norrish

Faculty of Informatics - Papers (Archive)

This paper presents an offline programming (OLP) system for a complex robotic welding cell using DELMIA Automation. The goals of this research are aimed at investigating the feasibility of taking a commercially available robotic simulation package, DELMIA, and to use a Visual Basic Automation interface to reduce the programming time by creating automated ‘modules’ to carry out some of the tasks in the OLP process. The paper first investigates and presents the structure of OLP as a discreet method of individual steps. These steps are then evaluated for their potential as an automation candidate. The methods in which these steps …

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Improving Bdd Cryptosystems In General Lattices, Willy Susilo, Thomas V. Plantard, Michael Rose Jan 2011

Improving Bdd Cryptosystems In General Lattices, Willy Susilo, Thomas V. Plantard, Michael Rose

Faculty of Informatics - Papers (Archive)

No abstract provided.

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Age Estimation Based On Extended Non-Negative Matrix Factorization, Ce Zhan, Wanqing Li, Philip Ogunbona Jan 2011

Age Estimation Based On Extended Non-Negative Matrix Factorization, Ce Zhan, Wanqing Li, Philip Ogunbona

Faculty of Informatics - Papers (Archive)

Previous studies suggested that local appearance-based methods are more efficient than geometric-based and holistic methods for age estimation. This is mainly due to the fact that age information are usually encoded by the local features such as wrinkles and skin texture on the forehead or at the eye corners. However, the variations of theses features caused by other factors such as identity, expression, pose and lighting may be larger than that caused by aging. Thus, one of the key challenges of age estimation lies in constructing a feature space that could successfully recovers age information while ignoring other sources of …

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Lifespan Theorem For Simple Constrained Surface Diffusion Flows, Glen Wheeler Jan 2011

Lifespan Theorem For Simple Constrained Surface Diffusion Flows, Glen Wheeler

Faculty of Informatics - Papers (Archive)

We consider closed immersed hypersurfaces in R3 and R4 evolving by a special class of constrainedsurfacediffusionflows. This class of constrainedflows includes the classical surfacediffusionflow. In this paper we present a LifespanTheoremfor these flows, which gives a positive lower bound on the time for which a smooth solution exists, and a small upper bound on the total curvature during this time. The hypothesis of the theorem is that the surface is not already singular in terms of concentration of curvature. This turns out to be a deep property of the initial manifold, as the lower bound on maximal time obtained depends …

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Threshold Ring Signature Without Random Oracles, Tsz Hon Yuen, Joseph K. Liu, Man Ho Allen Au, Willy Susilo, Jianying Zhou Jan 2011

Threshold Ring Signature Without Random Oracles, Tsz Hon Yuen, Joseph K. Liu, Man Ho Allen Au, Willy Susilo, Jianying Zhou

Faculty of Informatics - Papers (Archive)

In this paper, we present the notion and construction of threshold ring signature without random oracles. This is the first scheme in the literature that is proven secure in the standard model. Our scheme extends the Shacham-Waters signature from PKC 2007 in a non-trivial way. We note that our technique is specifically designed to achieve a threshold ring signature in the standard model. Interestingly, we can still maintain the signature size to be the same as the Shacham-Waters signature, while only a tiny computation cost is added.

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Electronic Cash With Anonymous User Suspension, Man Ho Au, Willy Susilo, Yi Mu Jan 2011

Electronic Cash With Anonymous User Suspension, Man Ho Au, Willy Susilo, Yi Mu

Faculty of Informatics - Papers (Archive)

Electronic cash (E-cash) is the digital counterpart of cash payment. They allow users to spend anonymously unless they “double spend” their electronic coins. However, it is not possible to prevent users from misbehaving under some other subjective definitions of misbehavior, such as money laundering. One solution is to incorporate a trusted third party (TTP), which, upon complaint, uses its power to deanonymize the suspected user. This solution, known as fair e-cash, is not fully satisfactory since additional measure has to be taken to stop misbehaving users from further abusing the system after they have been identified. We present a e-cash …

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Pricing Of Volatility Derivatives Using 3/2-Stochastic Models, Joanna Goard Jan 2011

Pricing Of Volatility Derivatives Using 3/2-Stochastic Models, Joanna Goard

Faculty of Informatics - Papers (Archive)

Analytic solutions are found for prices of both variance and volatility swaps and VIX options under new 3/2- stochastic models for the dynamics of the underlying assets. The main features of the new stochastic differential equations are an empirically validated cv3/2 diffusion term, a nonlinear drift providing a balancing effect of a stronger mean reversion with high volatility, and for the case of the variance and volatility swaps, a free function of time as a moving target in the reversion term, allowing additional flexibility for model calibration against market data.

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The Effect Of Incomplete Mixing Upon The Performance Of A Membrane-Coupled Anaerobic Fermentor, Ahmed Hussein Msmali, Mark I. Nelson, John M. Kavanagh Jan 2011

The Effect Of Incomplete Mixing Upon The Performance Of A Membrane-Coupled Anaerobic Fermentor, Ahmed Hussein Msmali, Mark I. Nelson, John M. Kavanagh

Faculty of Informatics - Papers (Archive)

We consider a model to describe the performance of a membrane-coupled anaerobic fermentor which was developed and calibrated using experimental data by Kim and Chung (2010). The model consists of six differential equations, modelling the concentration of five biochemical species and the rate of gasification. In the original work it was assumed that reactor is well-mixed. We use a two parameter mixing model to investigate the effect of incomplete mixing upon the performance of this process. The parameters in the mixing mode are the size of the stagnant region and a parameter controlling the degree of mixing between the regions. …

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Ontology Based Search Mechanism In Bilingual Database Resource, Norasykin Mohd Zaid, Sim Kim Lau Jan 2011

Ontology Based Search Mechanism In Bilingual Database Resource, Norasykin Mohd Zaid, Sim Kim Lau

Faculty of Informatics - Papers (Archive)

The focus of our research is to investigate how ontology based search system can help a novice researcher in literature search in an online academic database. In this paper, we will describe ontology construction which is based on the existing relational database system. We will demonstrate three solutions using this ontology to resolve our problems in synonym relation, short-form-term and full-term search, and bilingual retrieval.

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Vibration Control Of Seat Considering Vehicle Suspension And Human-Body Models, Haiping Du, Weihua Li, Nong Zhang Jan 2011

Vibration Control Of Seat Considering Vehicle Suspension And Human-Body Models, Haiping Du, Weihua Li, Nong Zhang

Faculty of Informatics - Papers (Archive)

Vehicle seat suspension is one of very important components to provide ride comfort, in particular, commercial vehicles, to reduce driver fatigue due to long hours driving. This paper presents a study on active control of seat suspension to reduce vertical vibration transmitted from uneven road profile to driver body. The control problem will be firstly studied by proposing an integrated seat suspension model which includes vehicle chassis suspension, seat suspension, and driver body model. This is a new concept in the field of study because most of the current active and semi-active seat suspension studies only consider seat suspension or …

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Partially Overlapped Range Images Registration Based On Fringe Pattern Profilometry, Xiaochen He, Jiangtao Xi, Yanguang Yu Jan 2011

Partially Overlapped Range Images Registration Based On Fringe Pattern Profilometry, Xiaochen He, Jiangtao Xi, Yanguang Yu

Faculty of Informatics - Papers (Archive)

Registration of two three-dimensional (3-D) point sets is a fundamental problem of 3-D shape measurement and modeling pipeline. This paper investigates the automatic pair-wise method to register partially overlapped range images generated by self-developed fringe pattern profilometry (FPP) system. The method is based on the classic iterative closest point (ICP) algorithm but combined with several extensions to adapt to the experimental data. Firstly, the distance function for correspondence finding is modified to be the weighted linear combination of positions and Euclidean invariant features for improving the probability of convergence. In addition, outliers can be discarded through robust statistics and adaptive …

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Heaven And Hell: Visions For Pervasive Adaptation, Ben Paechter, Jeremy Pitt, Nikola Serbedzija, Katina Michael, Jennifer Willies, Ingi Helgason Jan 2011

Heaven And Hell: Visions For Pervasive Adaptation, Ben Paechter, Jeremy Pitt, Nikola Serbedzija, Katina Michael, Jennifer Willies, Ingi Helgason

Faculty of Informatics - Papers (Archive)

With everyday objects becoming increasingly smart and the "info-sphere" being enriched with nano-sensors and networked to computationally-enabled devices and services, the way we interact with our environment has changed significantly, and will continue to change rapidly in the next few years. Being user-centric, novel systems will tune their behaviour to individuals, taking into account users' personal characteristics and preferences. But having a pervasive adaptive environment that understands and supports us "behaving naturally" with all its tempting charm and usability, may also bring latent risks, as we seamlessly give up our privacy (and also personal control) to a pervasive world of …

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Modelling Pattern Formation In Plants, M P. Edwards, S Pereverzyev, R S. Anderssen Jan 2011

Modelling Pattern Formation In Plants, M P. Edwards, S Pereverzyev, R S. Anderssen

Faculty of Informatics - Papers (Archive)

Performing simulations with simple models is a key activity in the recovery of information about the mechanisms which underlie the observed dynamics of biological processes, such as the posi- tioning of the hairs (trichomes) on the leaves of plants. The discovery of a robust representative model is a highly non-trivial process. Without appropriate constraints to regularize the choice of a model, the non-uniqueness of possibilities is vast. As acknowledged by Young (1983) in his modelling of pea leaf development, the degree of non-uniqueness can be reduced by constraining the model to reproduce the patterns observed in mutants as well as …

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The Application Of Location Based Services In National Emergency Warning Systems: Sms, Cell Broadcast Services And Beyond, Anas Aloudat, Katina Michael Jan 2011

The Application Of Location Based Services In National Emergency Warning Systems: Sms, Cell Broadcast Services And Beyond, Anas Aloudat, Katina Michael

Faculty of Informatics - Papers (Archive)

Location-based services can be broadly defined as any service that provides information pertinent to the current location of an active mobile handset at a specific window of time, regardless of the underlying delivery technology used to convey its information. To date, the short message service and cell broadcast service have been utilised by several countries during emergencies, however the future indicates that these services while cost-effective today, will almost certainly be superseded in the next five to ten years by newer more powerful capabilities. The path forward in location-based emergency services in Australia is given against a backdrop of the …

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Optimistic Fair Exchange Of Ring Signatures, Lie Qu, Guilin Wang, Yi Mu Jan 2011

Optimistic Fair Exchange Of Ring Signatures, Lie Qu, Guilin Wang, Yi Mu

Faculty of Informatics - Papers (Archive)

An optimistic fair exchange (OFE) protocol is an effective tool helping two parties exchange their digital items in an equitable way with assistance of a trusted third party, called arbitrator, who is only required if needed. In previous studies, fair exchange is usually carried out between individual parties. When fair exchange is carried our between two members from distinct groups, anonymity of the signer in a group could be necessary for achieving better privacy. In this paper, we consider optimistic fair exchange of ring signatures (OFERS), i.e. two members from two different groups can exchange their ring signatures in …

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Towards Greater Systemisation In Ci Research: An Exploration Of Social Development As A Framework For Comparison And Understanding, William Tibben Jan 2011

Towards Greater Systemisation In Ci Research: An Exploration Of Social Development As A Framework For Comparison And Understanding, William Tibben

Faculty of Informatics - Papers (Archive)

The theme of complexity alludes to the difficulties community informatics (CI) researchers face when analysing use of ICTs by communities. In response, de Moor (2009a, 2009b) and Stillman (2010) identify the need for greater systemisation of CI research that enables complex socio-technical processes to be analysed over multiple cases. The principle by which such systemisation should occur is open to debate. It seems improbable that a single theoretical approach, at least in the short term, is going to satisfy everyone as greater systemisation is pursued. The paper suggests that, as a first step, efforts should be devoted to better appreciation …

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A Mathematical Model For The Biological Treatment Of Industrial Wastewater In A Reactor Cascade, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy Jan 2011

A Mathematical Model For The Biological Treatment Of Industrial Wastewater In A Reactor Cascade, Rubayyi Turki Alqahtani, Mark I. Nelson, Annette L. Worthy

Faculty of Informatics - Papers (Archive)

Many industrial processes, particularly in the food industry, produce slurries or wastewaters containing high concentrations of biodegradable organic materials. Before these contaminated wastewaters can be discharged the concentration of the biodegradable organic pollutant must be reduced. One way to do this is to pass the wastewater through a bioreactor containing biomass which grows through consumption of the pollutant. Anaerobic conditions are often favoured for the processing of waste materials with high levels of biodegradable organic pollutants as these can be removed with low investment and operational costs. We investigate the steady state effluent concentration leaving a cascade of two reactors. …

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Development Of A Peer-To-Peer Information Sharing System Using Ontologies, Ghassan Beydoun, Graham Low, Numi Tran, Paul Bogg Jan 2011

Development Of A Peer-To-Peer Information Sharing System Using Ontologies, Ghassan Beydoun, Graham Low, Numi Tran, Paul Bogg

Faculty of Informatics - Papers (Archive)

Most existing agent-oriented methodologies ignore system extensibility, interoperability and reusability issues. Ontologies have been found to play a significant role in facilitating interoperability, reusability, MAS development activities (including MAS analysis and agent knowledge modeling) and MAS run-time operation (including agent communication and reasoning). However, most of the existing AOSE methodologies do not provide support for ontology-based MAS development. We present software engineering requirements for ontology-based development for MAS and examine an existing methodology, MOBMAS - a "Methodology for Ontology-Based MASs", which makes use of ontologies as a modeling tool. In this examination, we highlight how MOBMAS can be extended to …

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