Engineering Commons^™

Physics Workshop Tutorials: Views Of Life-Science Students, Roger A. Lewis

Faculty of Engineering - Papers (Archive)

[extract] Physics workshop tutorials, their implementation, and the purpose of this research: Workshop tutorials involve small groups of students using hands-on demonstrations and answering questions under the auspices of a tutor. Physics education research underpinned the development of workshop tutorials (Sharma, Millar and Seth 1999; Wilson, Peseta, Sharma and Millar 2002). Greater attendance at workshop tutorials is correlated with better examination marks (Sharma et al. 1999).

Status Of Outburst Research At The University Of Wollongong, Najdat I. Aziz, F. Sereshki, Dieter Bruggemann

Faculty of Engineering - Papers (Archive)

There has been an ongoing research on coal and gas outburst for the past two decades at the School of Civil, Mining and Environmental Engineering, University of Wollongong. Research study began with a humble beginning, initially conducting basic laboratory studies on the coal and gas properties, progressing into the determination of gas content of coal by sorption technique and the effect of gas pressures on coal strength. The present laboratory facilities and research interests are extended to include the study of coal permeability and shrinkage properties and their effect of gas drainage characteristics with respect to gas type, and pressures. …

Spectroscopy Of Acceptor States In Znse, R.A. Lewis, R.E.M Vickers, H. Nakata, Y.-J. Wang

Faculty of Engineering - Papers (Archive)

ZnSe is of growing technological interest for applications as diverse as blue LEDs and THz emitters.

Fem Analysis Of The Head Bending In Narrow Strip Hot Rolling, Limei Yang, Zhengyi Jiang, A. K. Tieu

Faculty of Engineering - Papers (Archive)

Head bending is a problem in narrow strip hot rolling, which causes a difficulty for strip to enter the next rolling pass of the tandem mills and affects the quality of products. A 2D FEM coupled thermal-stress analysis was employed to simulate the rolling process. The effects of the temperature difference, friction coefficient, reduction and the rolling speed on the head bending are discussed in the paper. Simulation results are in agreement with the measured values.

Supporting Collaboration And Multiple Views Of Building Models In Virtual Worlds, Mary Lou Maher, Mike A. Rosenman, Lan Ding, Gregory J. Smith, David Marchant, Andy Dong

Faculty of Engineering - Papers (Archive)

Collaboration in virtual environments has the potential to support communication and collaboration in multi-disciplinary teams. Current software for documenting and developing models of buildings focuses on supporting a single user who is a specialist in the specific software used within their own discipline. In this paper we report on the research, and a proposed approach, in supporting multiple disciplines in virtual worlds. We emphasise that the views and models are founded on the functional concerns of designers and the concerns are discipline specific. An agentbased approach to representing multiple views is described, along with a virtual world environment that supports …

Adaptive Battle Agents: Emergence In Artificial Life Combat Models, Thomas J. A. Baker, Matthew Botting, Matthew J. Berryman, Alex Ryan, Anne-Marie Grisogono, Derek Abbott

Faculty of Engineering - Papers (Archive)

We explore emergent behavior in an agent-based model of a complex system. The particular complex system we consider is a battlefield simulation. These agents are modeled in the RePast agent-based modeling environment. We will explore how agents of various capabilities and differing task sets affect the outcome of a battle. The capabilities of these agents include, but are not limited to, the ability to maneuver on the battlefield, receive and understand messages, formulate and send messages and attack enemy agents.

Who Wrote The Letter To The Hebrews? - Data Mining For Detection Of Text Authorship, Madeleine Sabordo, Shong Y. Chai, Matthew J. Berryman, Derek Abbott

Faculty of Engineering - Papers (Archive)

This paper explores the authorship of the Letter to the Hebrews using a number of different measures of rela,tionship between different texts of the New Testament. The methods used in the study include file zipping and compression techniques, prediction by the partial matching technique and the word recurrence interval technique. The long term motivation is that the techniques employed in this study may find applicability in future generation web search engines, email authorship identification, detection of plagiarism and terrorist email traffic filtration.

Thermomechanical Testing Of Nickel Base Superalloy Single Crystals, S S. Babu, J M. Vitek, S A. David, M Murugananth

Faculty of Engineering - Papers (Archive)

Thermomechanical response of single crystal superalloys during weld heating and cooling will affect cracking behavior in the heat-affected-zone (HAZ) and weld-metal (WM) regions. Thermomechanical response of these superalloys will depend on the phase fractions of ordered am ma-prime precipitates in the am ma matrix. During weld heating, the am ma-prime precipitates will dissolve as they approach the solvus temperature and some liquation may occur in the interdendritic regions. On cooling, the single-phase gamma matrix will decompose to a mixture of am ma and am ma-prime phases. In this work we evaluated the strength, ductility and reduction in area as a …

Application Of Computational Thermodynamic And Kinetic Models To Laser Surface Alloying, S S. Babu, S M. Kelly, R P. Martukanitz, M Murugananth

Faculty of Engineering - Papers (Archive)

Surface physical and mechanical properties can be tailored to different needs by the laser surface alloying process. These property modifications are made by localized melting of substrate material by laser beams with addition of alloying elements as well as hard particles. Through selection of proper hard particles, modification of underlying microstructure through rapid cooling and controlled alloying addition, one can tailor these surfaces for required properties. However, these processes are developed through extensive experimental trial-anderror methodology. This research shows an alternate design methodology by which these processes can be designed through computational thermodynamic and kinetic models.

Implementation Of A New Monte Carlo Simulation Tool For The Development Of A Proton Therapy Beam Line And Verification Of The Related Dose Distributions, G A. P Cirrone, G Cuttone, S Guatelli, S Lo Nigro, B Mascialino, M G. Pia, L Raffaele, G Russo, M G. Sabini

Faculty of Engineering - Papers (Archive)

Using the Monte Carlo simulation tool GEANT4 we simulated the hadron-therapy beam line of the CATANA center. CATANA is the unique italian hadron-therapy facility in which 62 AMeV proton beams are used for the radiotherapeutic treatment of choroidal and iris melanomas. All the elements, such as diffusers, range shifters, collimators and detectors, typical of a proton-therapy line were modelled. The CATANA beam line provides an ideal environment for the experimental testing and validation of the software developed. The software architecture was developed, and now the validation of the software is in its final stage. Simulated ranges, energy distribution, depth and …

The Need For Greater Standardisation In Utility Power Quality Measurements, Sean Elphick, Victor Gosbell

Faculty of Engineering - Papers (Archive)

The methodology and reasoning behind power quality monitoring by electricity utilities has undergone large scale changes in the past several years. In the past, power quality monitoring has been carried out in a reactive manner; that is, as a result of a specific problem and was usually only conducted in a localised area. Power quality monitoring instrumentation developed to suit fault finding applications and in many cases design was based upon customer requirements rather than a standard specification. While fault finding is still an essential facet of power quality monitoring, the fact that regulatory authorities are now taking an interest …

Flow Resistance And Bed Form Geometry In A Wide Alluvial Channel, Shu-Qing Yang, Soon-Keat Tan, Siow-Yong Lim

Faculty of Engineering - Papers (Archive)

This paper explores the underlying mechanism of flow resistance in a wide alluvial channel with bed forms. On the basis of published data, it is shown that the grain roughness can be taken as equal to 2 times the median diameter of the bed sediment. An empirical equation for the bed form roughness has been proposed, and it depends on the bed form height and bed form steepness. The influence of the bed form length and height on the total bed shear stress and energy slope is deliberated, and empirical expressions for the length of the separation zone behind the …

On-Site Nutrient Removal Using A 5-Stage Biological Reactor, Mohammed J. Mowlaei, Dharmappa Hagare, Muttucumaru Sivakumar

Faculty of Engineering - Papers (Archive)

Attempts to remove nutrients from municipal wastewater have traditionally been undertaken through physical, chemical and biological methods. However, not many efforts have been made to remove nutrients in on-site wastewater treatment systems. This paper represents the experimental results of an on-site biological nutrient removal process with the potential of wastewater reuse. The performance of this pilot-scale on-site biological reactor was evaluated according to Biochemical oxygen demand (BOD5) Total suspended solid (TSS), Total nitrogen (TN) and Total phosphorus (TP) removal efficiencies. The data revealed that this form of onsite wastewater treatment system is capable of removing up to 94% of BOD5, …

Defluroridation Using A Continuous Electrocoagulation (Ec) Reactor, Mohammad Emamjomeh, Muttucumaru Sivakumar

Faculty of Engineering - Papers (Archive)

Electrocoagulation (EC) is a process of passing a steady electric current through liquid using aluminium or iron electrodes to remove impurities in water. When aluminium electrodes are used, the aluminium goes into solution at the anode and hydrogen gas is released at the cathode and dissolution of A1 anodes produces aqueous aluminium species. Experiments were undertaken to investigate the effects of the different parameters such as: current density (12.5-50 A/m2), flow rate (150-400 mL/min), initial pH (4-8), and initial fluoride concentration (5-15 mg/L) on the fluoride removal efficiency in a continuous flow electrocoagulator. The experimental results showed that for an …

Magnetospectroscopy To 18 T Of Phosphorous Donor In Silicon, R. A. Lewis, R.E.M Vickers, Y.-J. Wang

Faculty of Engineering - Papers (Archive)

the intentional introduction of impurity atoms into high-quality semiconductor crystals is the basis of the electronic technology that underpins much of the modern information economy.

3d Finite Element Analysis Of Surface Roughness And Friction In Hot Strip Rolling, Zhengyi Jiang, A. K. Tieu

Faculty of Engineering - Papers (Archive)

Surface roughness of oxide scale and strip in hot strip rolling has a significant influence on the friction and lubrication conditions. In this paper, the authors present the measured surface roughness of oxide scale and strip by Atomic Force Microscope (AFM) and Surface Profilometer respectively for hot rolled strip on a Hille 100 experimental rolling mill. Based on the friction coefficient determined through a sensor roll on the rolling mill, a 3D rigid visco-plastic finite element simulation was carried out, and the relationship between the surface roughness and friction coefficient was investigated. Results show that the lubrication in hot strip …

Sliding Mode Control Of A Piezoelectric Actuator With Neural Network Compensating Rate-Dependent Hysteresis, Shuanghe Yu, Bijan Shirinzadeh, Gursel Alici, Julian Smith

Faculty of Engineering - Papers (Archive)

Piezoelectric actuators (PEA) are the fundamental elements for high-precision high-speed positioning/tracking task in many nanotechnology applications. However, the intrinsic hysteresis observed in PEAs has impaired their potential, specially, the motion accuracy. In this paper, the complicated nonlinear dynamics of PEA including hysteresis, creep, drift and time-delay etc. are treated as a black-box system exhibited as rate-dependent hysteresis. The multi-valued hysteresis is analyzed as a single-valued function so that a neural network (NN) can be built to model the hysteresis and its inversion. A sliding mode controller (SMC) augmented with inverse hysteresis model is then developed to compensate the hysteretic behavior, …

Piezospectroscopy Of The I Lines Of Gallium In Germanium, P. Fisher, R. E.M Vickers, P. S. Bowdler

Faculty of Engineering - Papers (Archive)

Piezospectra have been obtained for the closely spaced I lines of Ga in Ge. Small, homogeneous stresses have been obtained by abrading the optical faces. The symmetries of the final states of some of these lines have been deduced.

Effect Of Helical Pitch And Tensile Reinforcement Ratio On The Concrete Cover Spalling Off Load And Ductility Of Hsc Beams, Nuri M. Elbasha, Muhammad N. S Hadi

Faculty of Engineering - Papers (Archive)

[extract] In recent years a marked increase in the use of High Strength Concrete (HSC) has been evident in Australian building construction despite the fact that the current Australian design standard, AS3600 provides no design rules. HSC has been used extensively in civil construction projects world wide because it reduces the cross section and the weight for long construction members.

High strength concrete and high strength steel are used together to increase the load capacity and reduce the beams' cross section. Using these two materials to design over reinforced beams will lead to huge reduction of cost, which is a …

Greywater Recycling By Direct Ultrafiltration: Understanding Fouling, Long Nghiem, Nadine Oschmann, Andrea Schaefer

Faculty of Engineering - Papers (Archive)

Greywater is no doubt a valuable resource that can be used to alleviate water shortage and increase water conservation in individual households. It is particularly important for arid and semiarid regions like Australia. Treated greywater can also be used for many activities within the household such as toilet flushing, garden watering, car washing, or pavement cleansing. This study examines the fouling behaviour of submerged ultrafiltration membranes in greywater recycling under concentration variation of common greywater constituents. The results indicate that the use of ultrafiltration directly for greywater recycling in individual households is promising. As expected, increase in particulate matter concentration …

Efficiency Of Ideally Filtered Thermionic Devices, Mark F. O'Dwyer, T. E. Humphrey, C. Zhang, R. A. Lewis

Faculty of Engineering - Papers (Archive)

No abstract provided.

In Pursuit Of High-Force/High-Stroke Conducting Polymer Actuators, Geoffrey M. Spinks, Binbin Xi, Toni E. Campbell, Philip G. Whitten, Vahid Mottaghitalab, Mehrdad Bahrami Samani, G G. Wallace

Faculty of Engineering - Papers (Archive)

Conducting polymer actuators are being investigated for a number of applications. Both linear contracting/expanding and bending type actuators can be constructed that utilise the redox-induced volume changes in the conducting polymer. Improved actuator performance has been demonstrated by modifications to our helix-tube design. The pitch of the helix and bundling the actuators have increased the strain and force generated. Short-term improvements to the strain were also generated using new dopants, but cycle life was poor in this case. Further studies on the mechanism of actuation have continued to focus attention on the influence of the elastic modulus on the actuation …

Superconducting And Microstructural Properties Of Two Types Of Mgb2 Films Prepared By Pulsed Laser Deposition, Y. Zhao, M. Ionescu, M. Roussel, A. V. Pan, J. Horvat, S. X. Dou

Faculty of Engineering - Papers (Archive)

Significant differences in superconducting and microstructural properties between two types of MgB₂ films prepared by pulsed laser deposition were determined. A very high H_c2-T slope of 1.1 T/K was achieved in the in situ film. The J_c-H curves of the in situ film also show a much weaker field dependence than that of the ex situ film. The magneto-optical (MO) images show that at 4 K the flux penetrates the in situ MgB₂ film through random paths, while for the ex situ film, the flux penetration pattern is mostly repeatable, indicating a defect-controlled flux …

Absence Of Ferromagnetism And Strong Spin-Orbital Coupling In Polycrystalline In And Co Codoped Zn/Sub 1-X/Co/Sub 0.075/In /Sub X/O Oxide, Germanas Peleckis, Xiaolin Wang, S X. Dou

Faculty of Engineering - Papers (Archive)

Polycrystalline samples of In and Co codoped ZnO (Zn_1-xIn_xCo_0.075O; 0.010≤x≤0.020) oxide were prepared by solid-state synthesis technique. Phase purity and structure refinement done by means of the Rietveld analysis technique shows that both Co and In substitute properly into Zn positions. In doping, increased bulk conductivity of the samples at room temperature indicates an increase of charge carrier concentration. All samples showed paramagnetic behavior following Curie-Weiss law at close to room temperatures, with short range antiferromagnetic interaction with Θ≈-200 K. Effective magnetic moment (μ_eff) calculations showed a strong orbital contribution to the …