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Full-Text Articles in Social and Behavioral Sciences
Superposition Coded Modulation With Peak-Power Limitation, Jun Tong, Li Ping, Xiao Ma
Superposition Coded Modulation With Peak-Power Limitation, Jun Tong, Li Ping, Xiao Ma
Faculty of Engineering and Information Sciences - Papers: Part A
We apply clipping to superposition coded modulation (SCM) systems to reduce the peak-to-average power ratio (PAPR) of the transmitted signal. The impact on performance is investigated by evaluating the mutual information driven by the induced peak-power-limited input signals. It is shown that the rate loss is marginal for moderate clipping thresholds if optimal encoding/decoding is used. This fact is confirmed in examples where capacityapproaching component codes are used together with the maximum a posteriori probability (MAP) detection. In order to reduce the detection complexity of SCM with a large number of layers, we develop a suboptimal soft compensation (SC) method …
A Terahertz System Of Units, R A. Lewis
A Terahertz System Of Units, R A. Lewis
Faculty of Engineering and Information Sciences - Papers: Part A
It is proposed that a system of units based on the THz frequency and the properties of the THz photon has both aesthetic and technical advantages.
Bauschinger Effect In Nb And V Alloyed Line-Pipe Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis
Bauschinger Effect In Nb And V Alloyed Line-Pipe Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis
Faculty of Engineering and Information Sciences - Papers: Part A
The UOE process is used for cold forming of large diameter steel line-pipes. Pipe strength has been found to increase (work hardening) or decrease (Bauschinger effect) after the UOE process compared to the plate depending on the steel grade, plate and pipe processing history. The steel chemistry, through the presence of microalloy precipitates, and prior processing, through the size and distribution of microalloy precipitates and presence of retained work hardening, affects the magnitude of the Bauschinger effect. In this paper the microstructures of two (Nb and Nb-V alloyed) steel plates, in terms of (Nb,V)(C,N) particle distributions and dislocation densities, have …
Developments In Coal Mine Methane Drainage And Utilisation In Australia, Dennis John Black, Naj Aziz
Developments In Coal Mine Methane Drainage And Utilisation In Australia, Dennis John Black, Naj Aziz
Faculty of Engineering and Information Sciences - Papers: Part A
In recent years there has been significant development in the field of coalbed and coal mine methane drainage and utilisation in Australia. This development has, in part, been necessitated by the rapid increase in mine production capacity and the need to maintain the safety of the mine and its employees through effective management of coal seam gas emission and outburst risk. The increased awareness of the contribution of coal mine gas emission, estimated to account for 4-5% of Australia's 559 million tonnes of CO2 equivalent (MtCO2-e) annual greenhouse gas (GHG) emissions, is placing additional pressure on operators to increase coal …
A Control Strategy For Output Maximisation Of A Pmsg-Based Variable-Speed Wind Turbine, M E. Haque, K M. Muttaqi, M Negnevitsky
A Control Strategy For Output Maximisation Of A Pmsg-Based Variable-Speed Wind Turbine, M E. Haque, K M. Muttaqi, M Negnevitsky
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a control strategy for output maximisation of a direct drive permanent magnet synchronous generator (PMSG)-based small-scale variable-speed wind turbine. The control topology uses a single switch three-phase switch-mode rectifi er and the generator torque, and power is controlled by controlling the switch duty cycle of the switch. To extract maximum power from the wind, the torque reference of the PMSG is calculated from generator speed and wind turbine characteristics. From this torque reference, a current reference is calculated using measured DC link voltage and generator speed. The current error is then used to control the duty cycle …
Bolt Profile Configuration And Load Transfer Capacity Optimisation, Naj Aziz, Jan Nemcik, Chen Cao, Hossein Jalalifar
Bolt Profile Configuration And Load Transfer Capacity Optimisation, Naj Aziz, Jan Nemcik, Chen Cao, Hossein Jalalifar
Faculty of Engineering and Information Sciences - Papers: Part A
Both bolt profile shape and spacing (rib spacing) have been found to influence the bonding capacity of the grouted rock bolt. The bolt surface profile configuration has greater importance to rock bolting in strata reinforcement in mining than the steel rebar used in civil engineering construction. This is because a rock bolt in mining usually is subjected to greater dynamic loading than the steel rebar in civil engineering construction. The increased bonding capacity of a bolt is important when supported ground is either heavily fractured, faulted or the supported ground is of soft formation, typically that of coal measure rocks. …
Editorial: Special Issue Contributed From Chemeca 2008 - Mathematical Modeling, Mark Nelson, Brent Young, Harvinder Sidhu
Editorial: Special Issue Contributed From Chemeca 2008 - Mathematical Modeling, Mark Nelson, Brent Young, Harvinder Sidhu
Faculty of Engineering and Information Sciences - Papers: Part A
The papers in this issue of Chemical Product and Process Modeling are substantially those that arose from special sessions on "mathematical modeling" at the 36th Australasian Chemical Engineering Conference (held between 28th September to 1st October 2008, in Newcastle, Australia).
Low Temperature Graphene Growth, Shailesh Kumar, N Mcevoy, T. Lutz, G. Keeley, Nicholas Whiteside, Werner Blau, G. Duesberg
Low Temperature Graphene Growth, Shailesh Kumar, N Mcevoy, T. Lutz, G. Keeley, Nicholas Whiteside, Werner Blau, G. Duesberg
Faculty of Engineering and Information Sciences - Papers: Part A
We demonstrate the growth of graphene films on nickel substrates by chemical vapour deposition using acetylene at temperatures as low as 750 degrees celsius, opening a viable route for its scalable production. Raman spectroscopy was used to confirm defect-free mono and multilayer graphene at and above this temperature, and of defective graphene at lower temperatures. Atomic force microscopy and scanning electron microscopy performed directly on the films give an indication of graphene flake size, morphology and also the topography on substrate. An unexpected dependence of graphene thickness on precursor dwell time is reported. This together with low temperature growth suggests …
Security Vulnerability Of Id-Based Key Sharing Schemes, Jung Yeon Hwang, Taek-Young Youn, Willy Susilo
Security Vulnerability Of Id-Based Key Sharing Schemes, Jung Yeon Hwang, Taek-Young Youn, Willy Susilo
Faculty of Engineering and Information Sciences - Papers: Part A
Recently, several ID-based key sharing schemes have been proposed, where an initiation phase generates users' secret key associated with identities under the hardness of integer factorization. In this letter, we show that, unfortunately any key sharing scheme with this initiation phase is intrinsically insecure in the sense that the collusion of some users enables them to derive master private keys and hence, generating any user's secret key.
Statistical Analysis Of Overvoltages Due To The Energisation Of A 132 Kv Underground Cable, M Z. Daud, P Ciufo, S Perera
Statistical Analysis Of Overvoltages Due To The Energisation Of A 132 Kv Underground Cable, M Z. Daud, P Ciufo, S Perera
Faculty of Engineering and Information Sciences - Papers: Part A
Analysis by means of simulation studies is essential for providing useful information to distribution engineers and researchers regarding high frequency switching transients in cable systems. The behaviour of transients due to switching is strongly dependent on the pole closing span of the circuit breaker and also the closing angle of the power frequency voltage. This behaviour requires the study of overvoltage magnitude distributions to be carried out using a statistical approach. This paper presents an analysis of overvoltage sensitivity due to circuit breaker operations when energising an unloaded 132 kV underground cable system. Based on two approaches, the overvoltage values …
Numerical Study On Self-Similar Pulses In Mode-Locking Fiber Laser By Coupled Ginzburg-Landau Equation Model, Ting Lei, Chenghou Tu, Fuyun Lu, Yixin Deng, Enbang Li
Numerical Study On Self-Similar Pulses In Mode-Locking Fiber Laser By Coupled Ginzburg-Landau Equation Model, Ting Lei, Chenghou Tu, Fuyun Lu, Yixin Deng, Enbang Li
Faculty of Engineering and Information Sciences - Papers: Part A
A theoretical model is established to study the self-similar pulses in nonlinear polarization evolution (NPE) mode-locked fiber lasers. The propagation of pulse in single mode fibers and gain fibers are described by coupled Ginzburg- Landau equation (GLE). Two wave plates and a polarizer are considered to realize the NPE mechanism in simulation. This model describes the laser completely and provides some useful pulses' information. In our simulation the laser generates high quality self-similar pulses output. The region of steady self-similar pulses operation is found. The polarization states of different parts across the pulse are simulated along the laser cavity. It …
Influence Of Edge Rolling Reduction On Plate-Edge Stress Distribution During Finish Rolling, Hai-Liang Yu, Xiang-Hua Liu, Li-Qing Chen, Chang-Sheng Li, Ying Zhi, Xin-Wen Li
Influence Of Edge Rolling Reduction On Plate-Edge Stress Distribution During Finish Rolling, Hai-Liang Yu, Xiang-Hua Liu, Li-Qing Chen, Chang-Sheng Li, Ying Zhi, Xin-Wen Li
Faculty of Engineering and Information Sciences - Papers: Part A
Dimensions of one kind of stainless steel plate before finish rolling were obtained through analysis of the rough rolling processes by finite element method and updated geometrical method. The FE models of finish rolling process with a front edge roll were built, and influences of the edge rolling reduction on the stress change in the plate edge during finish rolling were analyzed. The results show that when the edge rolling reduction is increased from 0 mm to 2 mm, the compressive stress in plate corner clearly increases in edge rolling process, and the zone of tensile stress during whole rolling …
Novel Redesign Of A Pressure Leach Autoclave By A South African Platinum Producer, Joseph O. Roux, Madeleine Du Toit, David Shklaz
Novel Redesign Of A Pressure Leach Autoclave By A South African Platinum Producer, Joseph O. Roux, Madeleine Du Toit, David Shklaz
Faculty of Engineering and Information Sciences - Papers: Part A
The Impala Platinum Limited Base Metals Refinery in Springs, South Africa, refines convertor matte containing base metals and PGM's (platinum group metals) using a hydrometallurgical process. In addition to a PGM-rich concentrate that is further refined, the Base Metals Refinery produces nickel (in powder or briquette form), copper cathodes and cobalt powder. Five leaching stages are utilized to remove the base metals and impurities from the PGM concentrate. The project described in this paper involves a radical redesign of the second stage leach autoclave with the aim of reducing maintenance costs and downtime, increasing throughput and ensuring a safer working …
Adoption Of Dynamic Simulation For Energy Performance Rating Tool For Korean Residential Buildings: Edem-Samsung, Saeeta Ghauri, Cameron Johnstone, Jaemin Kim, Georgios Kokogiannakis, Paul Tuohy, Kyung-Hun Woo
Adoption Of Dynamic Simulation For Energy Performance Rating Tool For Korean Residential Buildings: Edem-Samsung, Saeeta Ghauri, Cameron Johnstone, Jaemin Kim, Georgios Kokogiannakis, Paul Tuohy, Kyung-Hun Woo
Faculty of Engineering and Information Sciences - Papers: Part A
Currently, there is a high emphasis on reducing the energy consumption and carbon emissions of buildings worldwide. Korea is facing an emerging issue of energy savings in buildings in perspective of new green economic policy. In this context, various policy measures including the energy efficiency ratings for buildings are being implemented for domestic and non-domestic buildings. In practice, design teams tend to prefer easy to use assessment tools to optimise energy performance and carbon ratings while they are concerned about calculation accuracy and the accurate representation of the dynamics involved associated with the characteristics of Korean residential buildings. This paper …
Observations Of Decomposition Of Martensite During Heat Treatment Of Steels Using Atom Probe Tomography, Elena V. Pereloma, Simon Peter Ringer, Ilana B. Timokhina, Peter D. Hodgson
Observations Of Decomposition Of Martensite During Heat Treatment Of Steels Using Atom Probe Tomography, Elena V. Pereloma, Simon Peter Ringer, Ilana B. Timokhina, Peter D. Hodgson
Faculty of Engineering and Information Sciences - Papers: Part A
The decomposition of martensite during tempering or ageing is an important phenomenon as it leads to changes in the mechanical properties. These changes could take place during both steel manufacturing or in-service. Thus, their understanding is required to predict the material performance. Recent advances in the development of local electrode atom probes has led to a significant increase in the analysed volume of material (up to 100 millions of atoms) and at the same time reduced the acquisition times. This allows improvement in data statistics when investigating fine nanoscale features, such as solute segregation, clustering and ultrafine precipitation. Selected results …
E-Learning Barriers In The United Arab Emirates: Preliminary Results From An Empirical Investigation, Lejla Vrazalic, Robert C. Macgregor, D Behl, Jean Fitzgerald
E-Learning Barriers In The United Arab Emirates: Preliminary Results From An Empirical Investigation, Lejla Vrazalic, Robert C. Macgregor, D Behl, Jean Fitzgerald
Faculty of Engineering and Information Sciences - Papers: Part A
E-learning is relatively new to the United Arab Emirates. Most tertiary institutions have allocated ICT resources to provide alternatives to the previously used teacher-centred "chalk and talk" approach to learning and teaching. However we have not yet developed a comprehensive understanding of the application of e-learning methods and resources in the tertiary education sector in the UAE. This paper describes a collaborative research project which empirically investigated the perceived barriers to e-learning for students studying at tertiary institutions in the UAE using an online questionnaire. The paper analyses the associations between e-learning barriers and students' age and gender. The ease …
Action Research In Emerging Technologies In Health Information Systems: Creating A Mobile Information Environment In A Hospital Ward, Linda Dawson, Julie Fisher, Stephen Weeding, Liza Heslop, Andrew Howard
Action Research In Emerging Technologies In Health Information Systems: Creating A Mobile Information Environment In A Hospital Ward, Linda Dawson, Julie Fisher, Stephen Weeding, Liza Heslop, Andrew Howard
Faculty of Engineering and Information Sciences - Papers: Part A
Wireless networks, mobile devices and associated applications are key emerging technologies ideal for nomadic workers such as clinicians in hospital ward settings. These mobile information environments can potentially enhance clinicians' use of patient management and clinical systems by providing decision support and clinical information at the bedside or point of care. Such technologies need to be critically assessed in a hospital environment for their wider potential and application for delivery of information at the point of care. This paper describes the use of action research methods in a project which analysed an existing clinical Information Communication Technology (ICT) environment in …
Understanding It Adoption And Consumption Within The Social Structure Of A Consumer's Economy, Sherman Ting, Linda Dawson, Chris Dubelaar
Understanding It Adoption And Consumption Within The Social Structure Of A Consumer's Economy, Sherman Ting, Linda Dawson, Chris Dubelaar
Faculty of Engineering and Information Sciences - Papers: Part A
Research into adoption, acceptance and consumption of Information Technology (IT) within its diffusion cycle has been extensively studied in Information Systems (IS) and marketing. However, research often focused too narrowly on technology adoption rates and drivers leading to technology adoption and acceptance. This paper discusses how understanding the social structure of a consumer's economy, a consumer's portfolio of capital resources, can reveal the individual's approach and experiences towards technology adoption and consumption present and future. It provides a novel multi-disciplinary and practical approach into understanding the technology consumer by looking at how economic, cultural, social, educational, technological and political capital …
Measuring The Success Of Intervention Programmes Designed To Increase The Participation Rate By Women In Computing, Annemieke Craig, Linda Dawson, Julie Fisher
Measuring The Success Of Intervention Programmes Designed To Increase The Participation Rate By Women In Computing, Annemieke Craig, Linda Dawson, Julie Fisher
Faculty of Engineering and Information Sciences - Papers: Part A
Many intervention programmes to encourage greater female participation in computer education and careers have been conducted in the last twenty years. These intervention programmes take considerable time, effort and money to design and implement. If success were to be measured by an increase in the percentage of female students undertaking computing courses then these programmes would have to be considered a failure. This paper describes a research project which examined fourteen intervention programmes in detail. From the perspective of the programme champions each of the intervention programmes was considered successful, even when this success was restricted to specific areas or …
A Method For Reducing Wave Based Teleoperator Reflections, L H. Bate, C D. Cook, Z Li
A Method For Reducing Wave Based Teleoperator Reflections, L H. Bate, C D. Cook, Z Li
Faculty of Engineering and Information Sciences - Papers: Part A
Wave variables guarantee stability for delayed teleoperation. They also introduce reflections which can prove very disorientating for an operator. This paper presents a new method for reducing the wave reflections when operating in nonlinear and unknown environments. Simulations and laboratory experiments shows the new method does not only guarantee stability but also reduce wave reflections allowing for improved velocity tracking and force feedback.
Experimental Study Of Using Renewable Energy In Yemen, Hani S. Alganahi, Kamaruzzaman S, Mohamed A, Ahmed M. Haidar, Ahmed Abdalla
Experimental Study Of Using Renewable Energy In Yemen, Hani S. Alganahi, Kamaruzzaman S, Mohamed A, Ahmed M. Haidar, Ahmed Abdalla
Faculty of Engineering and Information Sciences - Papers: Part A
During the last decade, there has been an increased interest to develop renewable energy technologies that could contribute to ever-increasing energy needs. This paper proposes a new PV array-wind-diesel generator hybrid system model to determine the optimal configuration of power systems relevant to different regions in Yemen, Sana’a and Aden. Various renewable and nonrenewable energy sources, energy storage and their applicability in terms of cost and performance are discussed. The collected data for the wind, solar radiation and diesel price were obtained from Civil Aviation & Meteorology Authority in Yemen. The Sensitivity analysis was carried out using Homer program. The …
Towards Problem Solving Methods In Multi-Agent Systems, Paul Bogg, Ghassan Beydoun, Graham Low
Towards Problem Solving Methods In Multi-Agent Systems, Paul Bogg, Ghassan Beydoun, Graham Low
Faculty of Engineering and Information Sciences - Papers: Part A
Problem Solving Methods (PSM) are abstract structures that describe specific reasoning processes employed to solve a set of similar problems and have proved very effective at enhancing reuse and extensibility in developing knowledge-based systems. We envisage that off-the-shelf PSMs can similarly assist in the development of agent-oriented solutions using Multi-Agent Systems (MAS). A challenge towards the effective use of PSMs in MAS is that current approaches to formulating PSMs do not adequately address the complexity of problems to which agent-oriented systems are suited. Towards addressing this, this paper focuses on providing an approach to guide developers in adequately formulating PSMs …
User-Driven Lossy Compression For Images And Video, Nathan Brewer, Nianjun Liu, Li Cheng, Lei Wang
User-Driven Lossy Compression For Images And Video, Nathan Brewer, Nianjun Liu, Li Cheng, Lei Wang
Faculty of Engineering and Information Sciences - Papers: Part A
In any given scene, a human observer is typically more interested in some objects than others, and will pay more attention to those objects they are interested in. This paper aims to capture this attention focusing behavior by selectively merging a fine-scale oversegmentation of a frame so that interesting regions are segmented into smaller regions than uninteresting regions. This results in a new type of image partitioning which reflects in the image the amount of attention we pay to a particular image region. This is done using a novel, interactive method for learning merging rules for images and videos based …
Pavement Scene Interpretation And Obstacle Detection By Large Margin Image Labeling, Ke Jia, Nianjun Liu, Lei Wang, Li Cheng
Pavement Scene Interpretation And Obstacle Detection By Large Margin Image Labeling, Ke Jia, Nianjun Liu, Lei Wang, Li Cheng
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a novel discriminative approach for pave-ment scene understanding and obstacle detection in real-world images. It overcomes the heavy constraints in previous systems such as a simple background, a specic obstacle, etc. The approach we exploited extends the bundle method to incorporate pairwise correlations among neighboring pixels, and adopts graph-cuts as the inference engine to attain the approximation efficiently. A set of robust features on both local and multi-scale level is also introduced that captures the general statistical properties of pavements and obstacles. The proposed approach is validated on real-world image database, and outperforms the current state-of-the-art visioned-based …
Frp Composites In Structures: Some Recent Research, J G. Teng, L Lam, J F. Chen, J G. Dai, T Yu
Frp Composites In Structures: Some Recent Research, J G. Teng, L Lam, J F. Chen, J G. Dai, T Yu
Faculty of Engineering and Information Sciences - Papers: Part A
An on-going research programme led by the first author at The Hong Kong Polytechnic University (PolyU) has addressed many issues in the application of fibre-reinforced polymer (FRP) composites in civil engineering structures. While the main focus of the programme has been on the behaviour and modelling of reinforced concrete (RC) and metallic structures strengthened with bonded FRP reinforcement, increasing attention has also been devoted to the use of FRP composites in new construction. This paper presents a brief summary of some of the latest advances of the research programme, covering the strengthening of RC structures with bonded FRP reinforcement, seismic …
Axial Compression Tests On Frp-Jacketed Circular Concrete-Filled Thin Steel Tubes, Y M. Hu, T Yu, J G. Teng
Axial Compression Tests On Frp-Jacketed Circular Concrete-Filled Thin Steel Tubes, Y M. Hu, T Yu, J G. Teng
Faculty of Engineering and Information Sciences - Papers: Part A
Fibre-reinforced polymer (FRP) jackets have been widely used to confine concrete columns to enhance their load-carrying capacity and ductility. More recently, the use of FRP jackets to improve the performance of hollow steel tubes and concrete-filled steel tubes has also been explored. This paper presents the results of a recent experimental study in which the behaviour of FRP-confined circular concrete-filled thin steel tubes under axial compression was examined. The experimental study included three series of tests and was focussed on the effects of the diameter-to-thickness ratio of the steel tube and the confinement stiffness of the FRP jacket. The test …
Regularity In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang
Regularity In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang
Faculty of Engineering and Information Sciences - Papers: Part A
In this talk, we give some estimates for solutions to the Monge-Amp`ere equation arising in optimal transportation. The Monge-Amp`ere equation under consideration has the following type
Pricing Variance Swaps With Stochastic Volatility, Song-Ping Zhu, Guang-Hua Lian
Pricing Variance Swaps With Stochastic Volatility, Song-Ping Zhu, Guang-Hua Lian
Faculty of Engineering and Information Sciences - Papers: Part A
Following the pricing approach proposed by Zhu & Lian [19], we present an exact solution for pricing variance swaps with the realized variance in the payoff function being a logarithmic return of the underlying asset at some pre-specified discrete sampling points. Our newly-found pricing formula is based on the Heston's [8] two-factor stochastic volatility model. The discovery of this exact and closed-form solution has significantly improved the computational efficiency involved in computing the value of variance swaps with discrete sampling points.
Survey Response As Organisational Behaviour: An Analysis Of The Annual Enterprise Survey, 2003-2007, Walter R. Davis, Nathaniel Pihama
Survey Response As Organisational Behaviour: An Analysis Of The Annual Enterprise Survey, 2003-2007, Walter R. Davis, Nathaniel Pihama
Faculty of Engineering and Information Sciences - Papers: Part A
Non-response is a matter of great concern to national statistical offices and a key issue for any survey because it can introduce bias to survey estimation. However, in this presentation, we focus on a business's decision to participate in a survey as an example of organisational behaviour and draw on basic organisational theory to explain why businesses may not respond to surveys (eg Tomaskovic-Devey et al 1994). The data are drawn from the Statistics New Zealand Respondent Management System, which links the response history of individual businesses in all Statistics NZ surveys with information from the Statistics NZ Business Frame. …
Spectral Flow Invariants And Twisted Cyclic Theory For The Haar State On Suq(2), A L. Carey, A Rennie, K Tong
Spectral Flow Invariants And Twisted Cyclic Theory For The Haar State On Suq(2), A L. Carey, A Rennie, K Tong
Faculty of Engineering and Information Sciences - Papers: Part A
In [A.L. Carey, J. Phillips, A. Rennie, Twisted cyclic theory and an index theory for the gauge invariant KMS state on Cuntz algebras. arXiv:0801.4605], we presented a K-theoretic approach to finding invariants of algebras with no non-trivial traces. This paper presents a new example that is more typical of the generic situation. This is the case of an algebra that admits only non-faithful traces, namely SUq.2/ and also KMS states. Our main results are index theorems (which calculate spectral flow), one using ordinary cyclic cohomology and the other using twisted cyclic cohomology, where the twisting comes from the generator of …