Social and Behavioral Sciences Commons^™

Speech Enhancement With An Acoustic Vector Sensor: An Effective Adaptive Beamforming And Post-Filtering Approach, Yuexian Zou, Peng Wang, Yong Wang, Christian Ritz, Jiangtao Xi

Faculty of Engineering and Information Sciences - Papers: Part A

Speech enhancement has an increasing demand in mobile communications and faces a great challenge in a real ambient noisy environment. This paper develops an effective spatialfrequency domain speech enhancement method with a single acoustic vector sensor (AVS) in conjunction with minimum variance distortionless response (MVDR) spatial filtering and Wiener post-filtering (WPF) techniques. In remote speech applications, the MVDR spatial filtering is effective in suppressing the strong spatial interferences and the Wiener postfiltering is considered as a popular and powerful estimator to further suppress the residual noise if the power spectral density (PSD) of target speech can be estimated properly. With …

Identity-Based Chameleon Hashing And Signatures Without Key Exposure, Xiaofeng Xiaofeng Chen, Fangguo Zhang, Willy Susilo, Haibo Tian, Jin Li, Kwangjo Kim

Faculty of Engineering and Information Sciences - Papers: Part A

The notion of chameleon hash function without key exposure plays an important role in designing secure chameleon signatures. However, all of the existing key-exposure free chameleon hash schemes are presented in the setting of certificate-based systems. In 2004, Ateniese and de Medeiros questioned whether there is an efficient construction for identity-based chameleon hashing without key exposure. In this paper, we propose the first identity-based chameleon hash scheme without key exposure based on the three-trapdoor mechanism, which provides an affirmative answer to the open problem. Moreover, we use the proposed chameleon hash scheme to design an identity-based chameleon signature scheme, which …

Purely Infinite Partial Crossed Products, Thierry Giordano, Adam Sierakowski

Faculty of Engineering and Information Sciences - Papers: Part A

Let (A, G, alpha) be a partial dynamical system. We show that there is a bijective corespondence between G-invariant ideals of A and ideals in the partial crossed prroduct A xalpha, r G provided the action is exact and residually topologically free.

Free Vibrations Of Interspersed Railway Track Systems In Three-Dimensional Space, Sakdirat Kaewunruen, Alexander Remennikov, Akira Aikawa, Hirotaka Sakai

Faculty of Engineering and Information Sciences - Papers: Part A

Statistically, the actual loading conditions for railway tracks are rather dynamic and transient. The dynamic loadings due to train and track interactions redistribute from the rails to the rail pad, from the rail pad to the railway sleeper, and from the railway sleeper to the underlying ground. Commonly, railway sleeper in track systems is modeled as a beam on elastic foundation. This study makes use of a calibrated finite element model of railway sleepers in a track system, in order to investigate the resonant frequencies and associated mode shapes of railway components in interspersed track systems. The numerical model takes …

Too Many Loads On Our Roads When Rail Is The Answer, Philip Laird

Faculty of Engineering and Information Sciences - Papers: Part A

“Without trucks, Australia stops” is now a fact of modern life. But when all costs are considered, road freight is an expensive way of moving large amounts of freight. And, as shown by ongoing fatal crashes involving large trucks, road freight can also be dangerous.

The main beneficiaries of road freight are not the truck drivers who work hard in a dangerous occupation, but the companies that choose to consign large quantities of freight by road. Road freight has seen strong growth, in part, due to good service levels and major road improvements that include highways with dual carriageways and …

Exact And Approximate Solutions For Options With Time-Dependent Stochastic Volatility, Joanna Goard

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper it is shown how symmetry methods can be used to find exact solutions for European option pricing under a time-dependent 3/2-stochastic volatility model View the MathML source. This model with A(t) constant has been proven by many authors to outperform the Heston model in its ability to capture the behaviour of volatility and fit option prices. Further, singular perturbation techniques are used to derive a simple analytic approximation suitable for pricing options with short tenor, a common feature of most options traded in the market.

Closure To "Deformation Of Coal Fouled Ballast Stabilized With Geogrid Under Cyclic Load" By Buddhima Indraratna, Ngoc Trung Ngo, And Cholachat Rujikiatkamjorn, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

The writers highly appreciate the keen feedback provided by the discusser and also for raising some other important aspects of the experimental program. While the writers are in general agreement with the discusser’s comments, some points warrant further clarification.

Nonlinear Analysis Of Axially Loaded Cicular Concrete-Filled Stainless Steel Tubular Short Columns, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

The experiments indicate that stainless steels in tension deform plastically more than stainless steels in compression. Therefore, the strain hardening of stainless steels in compression is much faster than that of stainless steels in tension. The full-range two-stage constitutive model for stainless steels assumes that stainless steels follow the same stress-strain behavior in compression and tension, which may underestimate the compressive strength of stainless steel tubes. This paper presents a fiber element model incorporating the recently developed full-range three-stage stress-strain relationships based on experimentally observed behavior for stainless steels for the nonlinear analysis of circular concrete-filled stainless steel tubular (CFSST) …

Analysis Of Subsynchronous Torsional Interaction Of Hvdc System Integrated Hydro Units With Small Generator-To-Turbine Inertia Ratios, Yin Chin Choo, Ashish Agalgaonkar, Kashem M. Muttaqi, Sarath Perera, Michael Negnevitsky

Faculty of Engineering and Information Sciences - Papers: Part A

The constant current controllers at high voltage direct current (HVDC) rectifier stations and the outer loops which set the reference to the current controller have potential to introduce negative damping on the nearby generating units. It is therefore vital to investigate the torsional interaction behavior between turbine-generator (TG) units and the HVDC systems over a frequency range of interest. In this paper, subsynchronous torsional interaction (SSTI) phenomenon for hydroelectric TG units with small generator-to-turbine inertia (GTI) ratios interconnected to an HVDC system has been investigated. The sensitivity of different system parameters, such as generating capacity and loading, DC power flow, …

Retrofitting Nonseismically Detailed Exterior Beam-Column Joints Using Concrete Covers Together With Cfrp Jacket, Muhammad N. S Hadi, Tung Minh Tran

Faculty of Engineering and Information Sciences - Papers: Part A

This paper introduces a new method for retrofitting reinforced concrete (RC) exterior beamcolumn T joints, using segmental circular concrete covers together with Carbon Fibre Reinforced Polymer (CFRP). Two RC T connections without transverse reinforcement at the joints were cast and tested. The first connection (Strengthened specimen, TS) was glued with the concrete covers around the column at the joint area to modify it from a square to a circular section and then it was wrapped with CFRP to strengthen its capacity. A load was first applied on the second connection (Repaired specimen, TR) to cause a serious failure then it …

Potassium-Uracil/Thymine Ring Cleavage Enhancement As Studied In Electron Transfer Experiments And Theoretical Calculations, D Almeida, M.-C. Bacchus-Montabonel, F Ferreira Da Silva, G Garcia, P Limao-Vieira

Faculty of Engineering and Information Sciences - Papers: Part A

We report experimental and theoretical studies on ring cleavage enhancement in collisions of potassium atoms with uracil/thymine in order to further increase the understanding of the complex mechanisms yielding such fragmentation pathways. In these electron transfer processes time-of-flight (TOF) negative ion mass spectra were obtained in the collision energy range 13.5 – 23.0 eV. We note that CNO– is the major ring breaking anion formed and its threshold formation is discussed within the collision energy range studied. Such decomposition process is supported by the first theoretical calculations in order to clarify how DNA/RNA pyrimidine bases fragmentation is enhanced in electron …

Role Of Microstructure In Susceptibility To Hydrogen Embrittlement Of X70 Microalloyed Steel, Daniel Hejazi, Ahmed Saleh, Ayesha Haq, Druce Dunne, Andrzej Calka, Azdiar A. Gazder, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of phases and steel processing on hydrogen uptake (diffusible and residual), surface and internal damage were evaluated using optical and scanning electron microscopy. The results have shown the fastest formation of blisters in ferrite-pearlite microstructure of strip, followed by equaixed ferrite-pearlite microstructure in normalised condition, then by ferrite-bainite microstructure. No blistering was observed in heat affected zone samples for up to 24 hrs charging. Analysis of hydrogen-induced cracking using electron back scattering diffraction has revealed that crack propagation has predominantly intragranular character without a clear preference on {001}, {110}, {112} and {123} planes and is independent of the …

Coherent And Tunable Terahertz Radiation From Graphene Surface Plasmon Polaritons Excited By An Electron Beam, Shenggang Liu, Chao Zhang, Min Hu, Xiaoxing Chen, Ping Zhang, Sen Gong, Tao Zhao, Renbin Zhong

Faculty of Engineering and Information Sciences - Papers: Part A

Although surface plasmon polaritons (SPPs) resonance in graphene can be tuned in the terahertz regime, transforming such SPPs into coherent terahertz radiation has not been achieved. Here, we propose a graphene-based coherent terahertz radiation source with greatly enhanced intensity. The radiation works at room temperature, it is tunable and can cover the whole terahertz regime. The radiation intensity generated with this method is 400 times stronger than that from SPPs at a conventional dielectric or semiconducting surface and is comparable to that from the most advanced photonics source such as a quantum cascade laser. The physical mechanism for this strong …

A New Version Of The Lupin Detector: Improvements And Latest Experimental Verification, M Caresana, C Cassell, M Ferrarini, E Hohmann, G P. Manessi, S Mayer, M Silari, V Varoli

Faculty of Engineering and Information Sciences - Papers: Part A

LUPIN-II is an upgraded version of LUPIN, a novel rem counter first developed in 2010 specifically conceived to work in pulsed neutron fields (PNFs). The new version introduces some modifications that improve the performance of the detector, in particular extending its upper detection limit in PNFs. This paper discusses the characteristics and the performance of the instrument. Measurements have been carried out in radiation fields characterized by very different conditions: the detector has first been exposed in PNFs with intensity up to 5 μSv per burst, where it could keep the H*(10) underestimation below 20% up to 500 nSv per …

An Adaptive Neuro Fuzzy Hybrid Control Strategy For A Semiactive Suspension With Magneto Rheological Damper, Pipit Wahyu Nugroho, Weihua Li, Haiping Du, Gursel Alici, Jian Yang

Faculty of Engineering and Information Sciences - Papers: Part A

The main function of a vehicle suspension system is to isolate the vehicle body from external excitation in order to improve passenger comfort and road holding and to stabilise its movement. This paper considers the implementation of an adaptive neuro fuzzy inference system (ANFIS) with a fuzzy hybrid control technique to control a quarter vehicle suspension system with a semiactive magneto rheological (MR) damper. A quarter car suspension model is set up with an MR damper and a semiactive controller consisting of a fuzzy hybrid skyhook-groundhook controller and an ANFIS model is also designed. The fuzzy hybrid controller is used …

Semi-Analytical Solutions For The Reversible Selkov Model With Feedback Delay, Khaled. Al Noufaey, Timothy Marchant

Faculty of Engineering and Information Sciences - Papers: Part A

Semi-analytical solutions for the reversible Selkov, or glycolytic oscillations model, are considered. The model is coupled with feedback at the boundary and considered in one-dimensional reaction-diffusion cell. This experimentally feasible scenario is analogous to feedback scenarios in a continuously stirred tank reactor. The Galerkin method is applied, which approximates the spatial structure of both the reactant and autocatalyst concentrations. This approach is used to obtain a lower-order, ordinary differential equation model for the system of governing equations. Steady-state solutions, bifurcation diagrams and the region of parameter space, in which Hopf bifurcations occur, are all found. The effect of feedback strength …

A Captcha Scheme Based On The Identification Of Character Locations, Duc Vu Nguyen, Yang-Wai Chow, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part A

CAPTCHAs are a standard security mechanism used on many websites to protect online services against abuse by automated programs, or bots. The purpose of a CAPTCHA is to distinguish whether an online transaction is being carried out by a human or a bot. Unfortunately, to date many existing CAPTCHA schemes have been found to be vulnerable to automated attacks. It is widely accepted that state-of-the-art in text-based CAPTCHA design requires that a CAPTCHA be resistant against segmentation. In this paper, we examine CAPTCHA usability issues and current segmentation techniques that have been used to attack various CAPTCHA schemes. We then …

A Decision Support Tool To Optimize Imrt Qa Workflow In A Multi-Vendor Equipment Environment, Sankar Arumugam, Aitang Xing, Philip Vial, Lois Holloway

Faculty of Engineering and Information Sciences - Papers: Part A

Development of a software tool to ease the Intensity Modulated Radiation Therapy (IMRT) pre-treatment Quality Assurance process is presented in this study. The delivery of IMRT involves equipment from multiple vendors. The limitations of the equipment involved in this chain will impact on the best choice of equipment. This often results in the user needing to use multiple pieces of equipment before determining the most appropriate choices to optimise the QA work flow. This is a time consuming process and potentially delays the start of patient treatment. Software was developed in-house to assist the decision making process, validating deliverability of …

The Resolvent Cocycle In Twisted Cyclic Cohomology And A Local Index Formula For The Podle's Sphere, Adam Rennie, Roger Senior

Faculty of Engineering and Information Sciences - Papers: Part A

We continue the investigation of twisted homology theories in the context of dimension drop phenomena. This work unifies previous equivariant index calculations in twisted cyclic cohomology. We do this by proving the existence of the resolvent cocycle, a finitely summable analogue of the JLO cocycle, under weaker smoothness hypotheses and in the more general setting of 'modular' spectral triples. As an application we show that using our twisted resolvent cocycle, we can obtain a local index formula for the Podles sphere. The resulting twisted cyclic cocycle has non-vanishing Hochschild class which is in dimension 2.

Total Electron Scattering Cross Sections For Pyrimidine And Pyrazine As Measured Using A Magnetically Confined Experimental System, M Fuss, A Sanz, Francisco Blanco, J C. Oller, Paulo Limao-Vieira, M J. Brunger, Gustavo García

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, a recently constructed apparatus for measuring electron scattering cross sections while applying a strong axial magnetic field is utilized for determining total scattering cross sections. The first molecules studied with this setup are pyrimidine (1,3-diazine) and pyrazine (1,4-diazine), whose total cross sections are obtained for the incident electron energy range of 8-500 eV. Quite good agreement with earlier theoretical predictions is found after accounting for the angular acceptance (angular resolution for forward scattering) of the apparatus. However, no other experimental total cross sections for electron scattering from pyrimidine or pyrazine have been found in the literature for …

Closure To "Active Shear Planes Of Bolted Connections Failing In Block Shear" By Drew D. A. Clements And Lip H. Teh, Drew Clements, Lip H. Teh

Faculty of Engineering and Information Sciences - Papers: Part A

The writers thank the discusser for the interest in the original paper and for the discussion, which provides the opportunity to clarify and reiterate a few points made in the original paper. The writers agree with the discusser that the behavior of bolted connections is not as simple as they appear to be to the casual observer, which is one reason why many structural collapses have been associated with connection failures. Furthermore, a substantial number of code equations for various ultimate limit states of bolted connections lead to considerable errors on either side of conservatism (Teh and Clements 2012; Teh …

The Path Space Of A Directed Graph, Samuel B. G Webster

Faculty of Engineering and Information Sciences - Papers: Part A

We construct a locally compact Hausdorff topology on the path space of a directed graph E and identify its boundary-path space ∂E as the spectrum of a commutative C*-subalgebra DE of C*(E). We then show that ∂E is homeomorphic to a subset of the infinite-path space of any desingularisation F of E. Drinen and Tomforde showed that we can realise C*(E) as a full corner of C*(F), and we deduce that DE is isomorphic to a corner of DF. Lastly, we show that this isomorphism implements the homeomorphism between the boundary-path spaces.

Smart Home Electricity Management In The Context Of Local Power Resources And Smart Grid, Weiliang Zhao, Lan Ding, Paul Cooper, Pascal Perez

Faculty of Engineering and Information Sciences - Papers: Part A

This work proposes a smart home electricity management approach that can predict and schedule electricity demand and supply by considering: the 'state' of the smart grid, local power generation capacity, and electrical consumption of household appliances. The prediction of weather conditions and the immediate and longer-term plans of the residential home occupants are crucial parameters in the smart home decision-making system that acts on behalf of the occupants. This paper provides a motivation example and associated scenarios, electrical energy supply/demand models, formalization of the cost optimization problem, and scheduling schemes for a smart home electricity management system in the context …

Relating Rejection Of Trace Organic Contaminants To Membrane Properties In Forward Osmosis: Measurements, Modelling And Implications, Ming Xie, Long D. Nghiem, William E. Price, Menachem Elimelech

Faculty of Engineering and Information Sciences - Papers: Part A

This study elucidates the relationship between membrane properties and the rejection of trace organic contaminants (TrOCs) in forward osmosis (FO). An asymmetric cellulose triacetate (CTA) and a thin-film composite (TFC) polyamide FO membrane were used for this investigation. The effective average pore radius (rp), selective barrier thickness over porosity parameter (l/ε), surface charge, support layer structural parameter (S), pure water permeability coefficient (A) and salt (NaCl) permeability coefficient (B) of the two membranes were systematically characterised. Results show that measured rejection of TrOCs as a function of permeate water flux can be well described by the pore hindrance transport model. …

A Review On The Occurrence Of Micropollutants In The Aquatic Environment And Their Fate And Removal During Wastewater Treatment, Yunlong Luo, Wenshan Guo, Huu Hao Ngo, Long Duc Nghiem, Faisal Ibney Hai, Jian Zhang, Shuang Liang, Xiaochang C. Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Micropollutants are emerging as a new challenge to the scientific community. This review provides a summary of the recent occurrence of micropollutants in the aquatic environment including sewage, surface water, groundwater and drinking water. The discharge of treated effluent from WWTPs is a major pathway for the introduction of micropollutants to surface water. WWTPs act as primary barriers against the spread of micropollutants. WWTP removal efficiency of the selected micropollutants in 14 countries/regions depicts compound-specific variation in removal, ranging from 12.5 to 100%. Advanced treatment processes, such as activated carbon adsorption, advanced oxidation processes, nanofiltration, reverse osmosis, and membrane bioreactors …

Identity Based Identification From Algebraic Coding Theory, Guomin Yang, Chik How Tan, Yi Mu, Willy Susilo, Duncan S. Wong

Faculty of Engineering and Information Sciences - Papers: Part A

Cryptographic identification schemes allow a remote user to prove his/her identity to a verifier who holds some public information of the user, such as the user public key or identity. Most of the existing cryptographic identification schemes are based on number-theoretic hard problems such as Discrete Log and Factorization. This paper focuses on the design and analysis of identity based identification (IBI) schemes based on algebraic coding theory. We first revisit an existing code-based IBI scheme which is derived by combining the Courtois-Finiasz-Sendrier signature scheme and the Stern zero-knowledge identification scheme. Previous results have shown that this IBI scheme is …

A New Payment System For Enhancing Location Privacy Of Electric Vehicles, Man Ho Au, Joseph K. Liu, Junbin Fang, Zoe L. Jiang, Willy Susilo, Jianying Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

An electric vehicle (EV) is a promising and futuristic automobile propelled by electric motors, using electrical energy stored in batteries or another energy storage device. Due to the need for the battery to be recharged, the cars will be required to visit a recharging infrastructure very frequently. This may disclose the users' private information, such as their location and, thus, compromise users' privacy. In this paper, we propose a new payment system that is suitable for EVs. Our system not only supports privacy protection (location privacy) but supports traceability in the case where the cars are stolen as well. Our …

Use Of A Large Multiparent Wheat Mapping Population In Genomic Dissection Of Coleoptile And Seedling Growth, Greg J. Rebetzke, Arunas P. Verbyla, Klara L. Verbyla, Matthew K. Morell, Colin R. Cavanagh

Faculty of Engineering and Information Sciences - Papers: Part A

Identification of alleles towards the selection for improved seedling vigour is a key objective of many wheat breeding programmes. A multiparent advanced generation intercross (MAGIC) population developed from four commercial spring wheat cultivars (cvv. Baxter, Chara, Westonia and Yitpi) and containing ca. 1000 F2-derived, F6:7 RILs was assessed at two contrasting soil temperatures (12 and 20 °C) for shoot length and coleoptile characteristics length and thickness. Narrow-sense heritabilities were high for coleoptile and shoot length (h2 = 0.68-0.70), indicating a strong genetic basis for the differences among progeny. Genotypic variation was large, and distributions of genotype means were approximately Gaussian …

Evaluating The Influence Of Virtual Reality-Based Training On Workers' Competencies In The Mining Industry, Shiva Pedram, Pascal Perez, Stephen Palmisano

Faculty of Engineering and Information Sciences - Papers: Part A

The Australian mining industry has achieved remarkable performance and safety results through continuous improvement of its training standards. Interactive virtual reality-based training is the most recent technology used to enhance workers' competencies in a safe and controlled environment that allows for replicable testing of extreme event scenarios. Like any other training method, VR-based training needs to be assessed in order to evaluate the advantages and limitations of this innovative technology, compared with more traditional approaches. Our research aims to design and implement an evaluation framework that can be used to assess VR-based training programs developed, amongst other training methods, by …

Improving Online Banking Quality In Developing Nations: A Libyan Case, Fouad Elgahwash, Mark Freeman, Alison E. Freeman

Faculty of Engineering and Information Sciences - Papers: Part A

While the global banking sector is one of the most up-to-date industries with regard to the use of the Internet and mobile technologies, developing countries (such as Libya) have not broadly adopted these technologies. For example, online banking is not offered or provided on a restricted basis by many banks in Libya. As developing countries now seek to catch up with the global environment, both banks and customers are likely to face challenges. Understanding the perceptions of customers with regard to online banking quality in developing countries is useful for informing future adoption strategies and hence improving relationships between banks …