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Full-Text Articles in Physical Sciences and Mathematics

Force Distribution For Double-Walled Carbon Nanotubes, Duangkamon Baowan, James M. Hill Jan 2006

Force Distribution For Double-Walled Carbon Nanotubes, Duangkamon Baowan, James M. Hill

Faculty of Informatics - Papers (Archive)

Advances in technology have led to the creation of many nano-scale devices and carbon nanotubes are representative materials to construct these devices. Double-walled carbon nanotubes with the inner tube oscillating can be used as gigahertz oscillators and form the basis of possible nano-electronic devices. Such gigahertz oscillating devices made from carbon nanotubes might be instrumental in the micro-computer industry, which is predominantly based on electron transport phenomena. There are many experiments and molecular dynamics simulations which show that a wave is generated on the outer cylinder by the oscillation of the carbon nanotubes and that the frequency of this wave …


Arbitrary Ratio Sample Rate Conversion Using B-Spline Interpolation For Software Defined Radio, Xiaojing Huang Jan 2006

Arbitrary Ratio Sample Rate Conversion Using B-Spline Interpolation For Software Defined Radio, Xiaojing Huang

Faculty of Informatics - Papers (Archive)

Arbitrary ratio sampling rate conversion (SRC) structure using B-spline interpolation is proposed for software defined radio (SDR) in this paper. By combining SRC with SDR’s transmitter/receiver filter, the constraint on SRC reconstruction filter can be relaxed, and an overall computational reduction can be achieved. The mixed-width B-spline is introduced so that both antiimaging and anti-aliasing requirements for SRC are satisfied. The passband droop introduced by the B-spline interpolation is compensated by a linear phase digital filter incorporated in the SRC structure so that the overall frequency response approaches the desired frequency response of the SDR’s transmitter/receiver filter. To make the …


Facial Expression Recognition For Multiplayer Online Games, Ce Zhan, Wanqing Li, Philip O. Ogunbona, Farzad Safaei Jan 2006

Facial Expression Recognition For Multiplayer Online Games, Ce Zhan, Wanqing Li, Philip O. Ogunbona, Farzad Safaei

Faculty of Informatics - Papers (Archive)

The Multiplayer Online Game (MOG) becomes more popular than any other types of computer games for its collaboration, communication and interaction ability. However, compared with the ordinary human communication, the MOG still has many limitations, especially in communication using facial expressions. Although detailed facial animation has already been achieved in a number of MOGs, players have to use text commands to control avatars expressions. In this paper, we briefly review the state of the art in facial expression recognition and propose an automatic expression recognition system that can be integrated into a MOG to control the avatar’s facial expressions. We …


An Ontology-Based Approach For Expert And Knowledge Mining In Complex Multi-Agent Systems, Minjie Zhang, Xijin Tang, Quan Bai, Jifa Gu Jan 2006

An Ontology-Based Approach For Expert And Knowledge Mining In Complex Multi-Agent Systems, Minjie Zhang, Xijin Tang, Quan Bai, Jifa Gu

Faculty of Informatics - Papers (Archive)

Complex problems require diverse expertise and multiple techniques to solve. In order to solve such problems, complex multi-agent systems include numbers of heterogeneous agents, which may include both of human experts and autonomous agents, to work together toward some complex problems. Most complex multi-agent systems are working in open domains. Due to heterogeneities and dynamic working environments, expertise and capabilities of agents might not be well estimated and presented in the system. Therefore, how to discover useful knowledge from human and autonomous experts, make more accurate estimation for experts' capabilities and to find out suitable expert(s) to solve incoming problems …


Generic Scheduling Framework And Algorithm For Time-Varying Wireless Networks, Gengfa Fang, Yi Sun, Jihua Zhou, Jinglin Shi, Eryk Dutkiewicz Jan 2006

Generic Scheduling Framework And Algorithm For Time-Varying Wireless Networks, Gengfa Fang, Yi Sun, Jihua Zhou, Jinglin Shi, Eryk Dutkiewicz

Faculty of Informatics - Papers (Archive)

In this paper, the problem of scheduling multiple users sharing a time varying wireless channel is studied, in networks such as in 3G CDMA and IEEE 802.16. We propose a new generic wireless packet scheduling framework (WPSF), which takes into account not only the quality of service (QoS) requirements but also the wireless resource consumed. The framework is generic in the sense that it can be used with different resource constraints and QoS requirements depending on the traffic flow types. Subsequently, based on this framework a minimum rate and channel aware (MRCA) scheduling algorithm is presented. MRCA attempts to greedily …


Sava: A Novel Self-Adaptive Vertical Handoff Algorithm For Heterogeous Wireless Networks, Min Liu, Zhong-Cheng Li, Xiao-Bing Guo, Eryk Dutkiewicz, Ming-Hui Wang Jan 2006

Sava: A Novel Self-Adaptive Vertical Handoff Algorithm For Heterogeous Wireless Networks, Min Liu, Zhong-Cheng Li, Xiao-Bing Guo, Eryk Dutkiewicz, Ming-Hui Wang

Faculty of Informatics - Papers (Archive)

The next generation wireless networking (4G) is envisioned as a convergence of different wireless access technologies with diverse levels of performance. Vertical handoff (VHO) is the basic requirement for convergence of different access technologies and has received tremendous attention from the academia and industry all over the world. During the VHO procedure, handoff decision is the most important step that affects the normal working of communication. In this paper, we propose a novel vertical handoff decision algorithm, self- adaptive VHO algorithm (SAVA), and compare its performance with conventional algorithms. SAVA synthetically considers the long term movement region and short term …


Mathematical Modelling For A C60 Carbon Nanotube Oscillator, Barry J. Cox, Ngamta Thamwattana, James M. Hill Jan 2006

Mathematical Modelling For A C60 Carbon Nanotube Oscillator, Barry J. Cox, Ngamta Thamwattana, James M. Hill

Faculty of Informatics - Papers (Archive)

The discovery of fullerenes C60 and carbon nanotubes has created an enormous impact on nanotechnology. Because of their unique mechanical and electronic properties, such as low weight, high strength, flexibility and thermal stability, fullerenes C60 and carbon nanotubes are of considerable interest to researchers from many scientific areas. One problem that has attracted much attention is the creation of gigahertz oscillators. While there are difficulties for micromechanical oscillators, or resonators, to reach a frequency in the gigahertz range, it is possible for nanomechanical systems to achieve this. A number of studies have found that the sliding of the …


A System For The 3d Reconstruction Of The Human Face Using The Structured Light Approach, Dean Mcguire, Prashan Premaratne Jan 2006

A System For The 3d Reconstruction Of The Human Face Using The Structured Light Approach, Dean Mcguire, Prashan Premaratne

Faculty of Informatics - Papers (Archive)

This paper will describe a computer vision system under development with the aim of use in robust facial recognition applications. The system employs the structured light approach to solve the correspondence problem. The system has been designed with ease of use in mind with calibration procedures designed to be simple enough to be carried out without the use of precision measuring equipment, but robust enough to provide good quality 3D reconstructions. The hardware in use is of consumer grade and is being used in an unmodified form. Early reconstructions of faces based on the projection of a striped pattern have …


Wfms-Based Data Integration For E-Learning, Jianming Yong, Jun Yan, Xiaodi Huang Jan 2006

Wfms-Based Data Integration For E-Learning, Jianming Yong, Jun Yan, Xiaodi Huang

Faculty of Informatics - Papers (Archive)

As more and more organisations and institutions are moving towards the e-learning strategy, more and more disparate data are distributed by different e-learning systems. How to effectively use this vast amount of distributed data becomes a big challenge. This paper addresses this challenge and works out a new mechanism to implement data integration for e-learning. A workflow management system based (WFMS-based) data integration model is contributed to the e-learning.


Sampling Patchily Distributed Taxa: A Case Study Using Cost-Benefit Analyses For Sponges And Ascidians In Coastal Lakes Of New South Wales, Australia, P. B. Barnes, A. R. Davis, D. E. Roberts Jan 2006

Sampling Patchily Distributed Taxa: A Case Study Using Cost-Benefit Analyses For Sponges And Ascidians In Coastal Lakes Of New South Wales, Australia, P. B. Barnes, A. R. Davis, D. E. Roberts

Faculty of Science - Papers (Archive)

Estuaries worldwide are under increasing threat from human impacts. Because much of their fauna remains unstudied and in many cases undescribed, these systems present real challenges for effective management. In eastern Australia the study of estuarine fauna is often further complicated by its patchy distributions. This is particularly the case for assemblages of sessile invertebrates in coastal saline lakes. This study quantified distributions of sponges and ascidians at a hierarchy of spatial scales in the seagrass meadows of 2 coastal saline lakes in New South Wales, Australia. Nine species of sponge, many of which were undescribed, and 3 species of …


Targeting C-Reactive Protein For The Treatment Of Cardiovascular Disease, Mark B. Pepys, Gideon M. Hirschfield, Glenys A. Tennent, J Ruth Gallimore, Melvyn C. Kahan, Vittorio Bellotti, Philip N. Hawkins, Rebecca M. Myers, Martin D. Smith, Alessandra Polara, Alexander J. A Cobb, Steven V. Ley, J. Andrew Aquilina, Carol V. Robinson, Isam Sharif, Gillian A. Gray, Caroline A. Sabin, Michelle C. Jenvey, Simon E. Kolstoe, Darren Thompson, Stephen P. Wood Jan 2006

Targeting C-Reactive Protein For The Treatment Of Cardiovascular Disease, Mark B. Pepys, Gideon M. Hirschfield, Glenys A. Tennent, J Ruth Gallimore, Melvyn C. Kahan, Vittorio Bellotti, Philip N. Hawkins, Rebecca M. Myers, Martin D. Smith, Alessandra Polara, Alexander J. A Cobb, Steven V. Ley, J. Andrew Aquilina, Carol V. Robinson, Isam Sharif, Gillian A. Gray, Caroline A. Sabin, Michelle C. Jenvey, Simon E. Kolstoe, Darren Thompson, Stephen P. Wood

Faculty of Science - Papers (Archive)

Complement-mediated inflammation exacerbates the tissue injury of ischaemic necrosis in heart attacks and strokes, the most common causes of death in developed countries. Large infarct size increases immediate morbidity and mortality and, in survivors of the acute event, larger non-functional scars adversely affect long-term prognosis. There is thus an important unmet medical need for new cardioprotective and neuroprotective treatments. We have previously shown that human C-reactive protein (CRP), the classical acute-phase protein that binds to ligands exposed in damaged tissue and then activates complement1, increases myocardial and cerebral infarct size in rats subjected to coronary or cerebral artery ligation, respectively2,3. …


Carbon Nanotubes: Enhancing The Polymer Building Blocks For Intelligent Materials, Marc In Het Panhuis Jan 2006

Carbon Nanotubes: Enhancing The Polymer Building Blocks For Intelligent Materials, Marc In Het Panhuis

Faculty of Science - Papers (Archive)

Electroactive polymers can be engineered at the molecular level to recognise external stimuli, they are conductive and they are capable of localised processing. These are properties which make them ideal building blocks for intelligent materials. This article investigates the suitability of carbon nanotubes of enhancing (polymer) building blocks for intelligent materials.


Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, J F. Muller, T Blumenstock, Nicholas B. Jones, David W. Griffith, C P Rinsland, E Mahieu, S Wood, R De Beek, P Demoulin, M Buchwitz, P Duchatelet, C Frankenberg, A Gloudemans, T Kerzenmacher, I Kramer, J Mellqvist, H Shrijver, A Strandberg, D Smale, W Stremme, A G. Straume, R Sussmann, M Van Den Broek, T Wagner, K Strong, Aldona Wiacek, J R. Taylor, Hans Fast, Thorsten Warneke, Richard L. Mittermeier, Justus Notholt, Voltaire A. Velazco Jan 2006

Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, J F. Muller, T Blumenstock, Nicholas B. Jones, David W. Griffith, C P Rinsland, E Mahieu, S Wood, R De Beek, P Demoulin, M Buchwitz, P Duchatelet, C Frankenberg, A Gloudemans, T Kerzenmacher, I Kramer, J Mellqvist, H Shrijver, A Strandberg, D Smale, W Stremme, A G. Straume, R Sussmann, M Van Den Broek, T Wagner, K Strong, Aldona Wiacek, J R. Taylor, Hans Fast, Thorsten Warneke, Richard L. Mittermeier, Justus Notholt, Voltaire A. Velazco

Faculty of Science - Papers (Archive)

Total column amounts of CO, CH4, CO2 and N2O retrieved from SCIAMACHY nadir observations in its near-infrared channels have been compared to data from a ground-based quasi-global network of Fourier-transform infrared (FTIR) spectrometers. The SCIAMACHY data considered here have been produced by three different retrieval algorithms, WFM-DOAS (version 0.5 for CO and CH4 and version 0.4 for CO2 and N2O), IMAP-DOAS (version 1.1 and 0.9 (for CO)) and IMLM (version 6.3) and cover the January to December 2003 time period. Comparisons have been made for individual data, as well as for monthly averages. To maximize the number of reliable coincidences …


Detection Of Moisture Stress In Eucalyptus Camaldulensis Using Leaf-Level Spectral Reflectance: Implications For Remote Sensing, Laurie A. Chisholm Jan 2006

Detection Of Moisture Stress In Eucalyptus Camaldulensis Using Leaf-Level Spectral Reflectance: Implications For Remote Sensing, Laurie A. Chisholm

Faculty of Science - Papers (Archive)

Foliage moisture stress may be detectable by remote sensing using high resolution spectral data, but meaningful diagnosis requires that plant water status be assessed on the ground under controlled conditions. Design parameters of an experimental plantation of E. camaldulensis (River red gum), were used to examine tree-level responses to moisture stress, as measured by xylem water potential, and relationships to physiological parameters including spectral reflectance, chlorophyll flurescence, and cholorphyll across a range of stress categories.


Fitness Evaluation For Structural Optimisation Genetic Algorithms Using Neural Networks, Koren Ward, Timothy J. Mccarthy Jan 2006

Fitness Evaluation For Structural Optimisation Genetic Algorithms Using Neural Networks, Koren Ward, Timothy J. Mccarthy

Faculty of Informatics - Papers (Archive)

This paper relates to the optimisation of structural design using Genetic Algorithms (GAs) and presents an improved method for determining the fitness of genetic codes that represent possible design solutions by using a neural network to generalize fitness. Two problems that often impede design optimization using genetic algorithms are expensive fitness evaluation and high epistasis. In this paper we show that by using a neural network as a fitness approximator, optimal solutions to certain design problems can be achieved in significantly less generations and with considerably less fitness evaluations.


Application Of Surrogate Methods For Assessing The Bioavailability Of Pahs In Sediments To A Sediment Ingesting Bivalve, Stuart L. Simpson, Victoria L. Burston, Dianne F. Jolley, Kim Chau Jan 2006

Application Of Surrogate Methods For Assessing The Bioavailability Of Pahs In Sediments To A Sediment Ingesting Bivalve, Stuart L. Simpson, Victoria L. Burston, Dianne F. Jolley, Kim Chau

Faculty of Science - Papers (Archive)

The usefulness of two surrogate methods for rapidly determining the bioavailability of PAHs in hydrocarbon-contaminated marine sediments was assessed. Comparisons are made between the PAHs accumulated by the benthic bivalve, Tellina deltoidalis, and the extractable-PAHs determined using a 6-h XAD-2 resin desorption method and a 4-h gut fluid mimic (GFM) extraction method. There were significant positive relationships between PAH bioaccumulation by the bivalves and sediment PAH concentrations. These relationships were not improved by normalising the sediment PAH concentrations to the organic carbon concentration. The average percentage lipid content of the bivalves was 1.47 ± 0.22% and BSAFs for total-PAHs ranged …


Aeolian-Fluvial Interaction: Evidence For Late Quaternary Channel Change And Wind-Rift Linear Dune Formation In The Northwestern Simpson Desert, Australia, Gerald C. Nanson, Brian G. Jones, David M. Price, Tim Pietsch, C Bristow, Cameron B. Hollands Jan 2006

Aeolian-Fluvial Interaction: Evidence For Late Quaternary Channel Change And Wind-Rift Linear Dune Formation In The Northwestern Simpson Desert, Australia, Gerald C. Nanson, Brian G. Jones, David M. Price, Tim Pietsch, C Bristow, Cameron B. Hollands

Faculty of Science - Papers (Archive)

In central Australia the most easterly extent of the MacDonnell Ranges borders the northwestern Simpson Desert where widely spaced strike ridges intercept the regional linear dunefield. Topographic basins have disrupted regional drainage lines and isolated dune sets from the main dunefield. In the western part of Camel Flat basin large, red coloured linear dunes of fine sand, ~ 74 ka and older, are oriented almost due north. Through gaps in the ranges the Todd River traversed the eastern part of the basin until ~25 ka when it apparently avulsed ~25 km eastwards to its present position. Subsequently, linear dunes, smaller, …