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Full-Text Articles in Engineering
Monte Carlo Study Of The Potential Reduction In Out-Of-Field Dose Using A Patient-Specific Aperture In Pencil Beam Scanning Proton Therapy, Stephen J. Dowdell, Benjamin Clasie, Nicolas Depauw, Peter E. Metcalfe, Anatoly B. Rosenfeld, Hanne M. Kooy, Jacob B. Flanz, Harald Paganetti
Monte Carlo Study Of The Potential Reduction In Out-Of-Field Dose Using A Patient-Specific Aperture In Pencil Beam Scanning Proton Therapy, Stephen J. Dowdell, Benjamin Clasie, Nicolas Depauw, Peter E. Metcalfe, Anatoly B. Rosenfeld, Hanne M. Kooy, Jacob B. Flanz, Harald Paganetti
Faculty of Engineering - Papers (Archive)
This study is aimed at identifying the potential benefits of using a patientspecific aperture in proton beam scanning. For this purpose, an accurate Monte Carlo model of the pencil beam scanning (PBS) proton therapy (PT) treatment head at Massachusetts General Hospital (MGH) was developed based on an existing model of the passive double-scattering (DS) system. The Monte Carlo code specifies the treatment head at MGH with sub-millimeter accuracy. The code was configured based on the results of experimental measurements performed at MGH. This model was then used to compare out-of-field doses in simulated DS treatments and PBS treatments. For the …
How To Achieve Maximum Charge Carrier Loading On Heteroatom-Substituted Graphene Nanoribbon Edges: Density Functional Theory Study, Ting Liao, Chenghua Sun, Ziqi Sun, Aijun Du, Denisa Hulicova-Jurcakova, Sean C. Smith
How To Achieve Maximum Charge Carrier Loading On Heteroatom-Substituted Graphene Nanoribbon Edges: Density Functional Theory Study, Ting Liao, Chenghua Sun, Ziqi Sun, Aijun Du, Denisa Hulicova-Jurcakova, Sean C. Smith
Faculty of Engineering - Papers (Archive)
The practical number of charge carriers loaded is crucial to the evaluation of the capacity performance of carbon-based electrodes in service, and cannot be easily addressed experimentally. In this paper, we report a density functional theory study of charge carrier adsorption onto zigzag edge-shaped graphene nanoribbons (ZGNRs), both pristine and incorporating edge substitution with boron, nitrogen or oxygen atoms. All edge substitutions are found to be energetically favorable, especially in oxidized environments. The maximal loading of protons onto the substituted ZGNR edges obeys a rule of [8-n- 1], where n is the number of valence electrons of the edge-site atom …
Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao
Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao
Faculty of Engineering - Papers (Archive)
The original and high-pressure torsion (HPT) processed Zircaloy-4 materials were hydrided using gaseous hydrogen charging at different hydrogen pressures (10, 15 and 20 atm). The phase and microstructural evolutions of the samples during hydriding were characterized. It showed that when hydriding at the identical conditions, more hydrides tended to form in the HPT samples compared to that of the original ones. At a hydrogen pressure of 20 atm, the HPT sample was completely converted to ε-ZrH2 while some δ-ZrH1.66 hydrides (volume fraction ~5.73%) were present in the material without HPT preprocessing. The HPT samples exhibited high potential for the hydride …
A Laboratory Study Of Railway Ballast Behaviour Under Various Fouling Degree, Cholachat Rujikiatkamjorn, Buddhima Indraratna, Ngoc Trung Ngo, Matthew Coop
A Laboratory Study Of Railway Ballast Behaviour Under Various Fouling Degree, Cholachat Rujikiatkamjorn, Buddhima Indraratna, Ngoc Trung Ngo, Matthew Coop
Faculty of Engineering - Papers (Archive)
This paper presents a laboratory study of interface behavior between ballast and geogrid under various degree of fouling by coal fines. The stress-displacement behaviour of fresh and fouled ballast with geogrid was investigated through a series of large-scale direct shear tests where the fouling degree varied from 0% to 95% Void Contamination Index (VCI), at normal stresses ranging from 15kPa to 75kPa. The results showed that geogrid enhances the shear strength and increases apparent angle of shearing resistance, while only slightly reduces the vertical displacement of the composite geogrid-ballast system. However, when ballast was contaminated by coal fines, the influences …
Importance Of The Relative Advantage Of Rfid As Enabler Of Asset Management In The Healthcare: Results From A Delphi Study, Samuel Fosso Wamba, Eric W. T Ngai
Importance Of The Relative Advantage Of Rfid As Enabler Of Asset Management In The Healthcare: Results From A Delphi Study, Samuel Fosso Wamba, Eric W. T Ngai
Faculty of Engineering and Information Sciences - Papers: Part A
Compared with bar coding technology, what is the importance of the relative advantage of radio frequency identification (RFID) in the healthcare sector? What is the effect of RFID technology on asset management-related processes in healthcare? What are the top-ranked asset management-related processes associated with the adoption and use of RFID technology in this sector? To answer these questions, a three-round Delphi study was conducted among experts working on RFID technology. In the study, a list of 12 processes related to the relative advantage of RFID and 10 processes related to RFID-enabled asset management applications in the healthcare sector were derived …
Experimental Study On Chain-Die Forming For Ultrahigh Strength Steel (Uhss), Yuankun Zhang, Shichao Ding
Experimental Study On Chain-Die Forming For Ultrahigh Strength Steel (Uhss), Yuankun Zhang, Shichao Ding
Faculty of Engineering and Information Sciences - Papers: Part A
With the increasing applications of UHSS for the automotive industry, it becomes more and more important to develop a new forming technology as an alternative or even a replacement to roll forming to overcome the difficulties and problems of manufacturing the UHSS. With the increase of material's strength and decrease of its thickness, the springback of the material becomes more difficult to predict, which directly affects the application of roll forming in UHSS. Chain-die Forming, as an alternative to roll forming proposed and developed recently in Australia, is expected to be a solution to the problems addressed. It has been …
Experimental Study On Adhesion Of Oxide Scale On Hot-Rolled Steel Strip, Xianglong Yu, Dongbin Wei, Xiaodong Wang, Zhengyi Jiang
Experimental Study On Adhesion Of Oxide Scale On Hot-Rolled Steel Strip, Xianglong Yu, Dongbin Wei, Xiaodong Wang, Zhengyi Jiang
Faculty of Engineering - Papers (Archive)
An experimental method was developed to study the adherence properties of the oxide scale formed on microalloyed low carbon steel after hot strip rolling. The evolution of the oxide scale during laminar cooling was investigated using Gleeble 3500 Thermal-Mechanical Simulator connected with a humid air generator. After the sample cooled down to ambient temperature, the oxide scale was protected by lacquer to prevent the scale from losing. Physicochemical characteristics of the oxide scale were examined and the adherence mechanism was discussed. Decomposed wustite a mixture of α-iron and magnetite (Fe3O4), can substantially improve the integrity of …
Charge Carrier Exchange At Chemically Modified Graphene Edges: A Density Functional Theory Study, Ting Liao, Chenghua Sun, Aijun Du, Ziqi Sun, Denisa Hulicova-Jurcakova, Sean Smith
Charge Carrier Exchange At Chemically Modified Graphene Edges: A Density Functional Theory Study, Ting Liao, Chenghua Sun, Aijun Du, Ziqi Sun, Denisa Hulicova-Jurcakova, Sean Smith
Faculty of Engineering - Papers (Archive)
Heteroatom doping on the edge of graphene may serve as an effective way to tune chemical activity of carbon-based electrodes with respect to charge carrier transfer in an aqueous environment. In a step towards developing mechanistic understanding of this phenomenon, we explore herein mechanisms of proton transfer from aqueous solution to pristine and doped graphene edges utilizing density functional theory. Atomic B-, N-, and O- doped edges as well as the native graphene are examined, displaying varying proton affinities and effective interaction ranges with the H3O+ charge carrier. Our study shows that the doped edges characterized by more dispersive orbitals, …
Study On A Seawater Hydraulic Piston Pump With Check Valves For Underwater Tools, X He, B Zhu, Y Liu, Z Jiang
Study On A Seawater Hydraulic Piston Pump With Check Valves For Underwater Tools, X He, B Zhu, Y Liu, Z Jiang
Faculty of Engineering - Papers (Archive)
The aim of this study is to develop a seawater hydraulic piston pump for the power pack of an underwater tool system. A pump with check valves and oil–water-separated structure was selected for the purpose of improving its tolerance to particles when applied in open-circuit system. A novel ‘anti-loosening’ structure was introduced for the piston/shoe assembly. To improve the anti-wear and anti-corrosion performances of the piston and sleeve pairs under seawater lubrication, carbon fibre-reinforced polyetheretherketone was injected as an inner of the sleeve, and synthesized WC was formed on the piston with improved surface hardness. The unbalance problem of the …
Study Of Vacancy-Type Defects By Positron Annihilation In Ultrafine-Grained Aluminum Severely Deformed At Room And Cryogenic Temperatures, L H. Su, Cheng Lu, Lizi He, L C. Zhang, P Guagliardo, A K. Tieu, S N. Samarin, J F. Williams, H J. Li
Study Of Vacancy-Type Defects By Positron Annihilation In Ultrafine-Grained Aluminum Severely Deformed At Room And Cryogenic Temperatures, L H. Su, Cheng Lu, Lizi He, L C. Zhang, P Guagliardo, A K. Tieu, S N. Samarin, J F. Williams, H J. Li
Faculty of Engineering - Papers (Archive)
"Commercial-purity aluminum was processed by equal-channel angular pressing (ECAP) at room temperature (RT-ECAP) and cryogenic temperature (CT-ECAP) with liquid nitrogen cooling between two successive passes.It was found that the RT-ECAPed samples showed equiaxed microstructure after 4 and 8 ECAP passes, while the CT-ECAPed samples displayed slightly elongated microstructure and slightly smaller grain size.Moreover, the CT-ECAPed samples had higher hardness values than the RT-ECAPed samples subjected to the same amount of deformation.Positron annihilation lifetime spectroscopy (PALS) was used to investigate the evolution of vacancy-type defects during the ECAP deformation process.The results showed that three types of defects existed in the ECAPed …
Large Area Silicon Microdosimeter For Dosimetry In High Let Space Radiation Fields: Charge Collection Study, Jayde Livingstone, Dale A. Prokopovich, Michael L. F Lerch, Marco Petasecca, Mark I. Reinhard, Hiroshi Yasuda, Marco Zaider, James F. Ziegler, Vincent L. Pisacane, John F. Dicello, Vladimir L. Perevertaylo, Anatoly B. Rosenfeld
Large Area Silicon Microdosimeter For Dosimetry In High Let Space Radiation Fields: Charge Collection Study, Jayde Livingstone, Dale A. Prokopovich, Michael L. F Lerch, Marco Petasecca, Mark I. Reinhard, Hiroshi Yasuda, Marco Zaider, James F. Ziegler, Vincent L. Pisacane, John F. Dicello, Vladimir L. Perevertaylo, Anatoly B. Rosenfeld
Faculty of Engineering - Papers (Archive)
Silicon microdosimeters for the characterisation of mixed radiation fields relevant to the space radiation environment have been under continual development at the Centre for Medical Radiation Physics for over a decade. These devices are useful for the prediction of single event upsets in microelectronics and for radiation protection of spacecraft crew. The latest development in silicon microdosimetry is a family of large-area n-SOI microdosimeters for real-time dosimetry in space radiation environments. The response of n-SOI microdosimeters to 2 MeV H and 5.5 MeV He ions has been studied to investigate their charge collection characteristics. The studies have confirmed 100% yield …
Hot Deformation Of Cast And Extruded Tial: An In-Situ Diffraction Study, Thomas Schmoelzer, Klaus-Dieter Liss, Svea Mayer, Kun Yan, Mark H. Reid, Rian J. Dippenaar, Matthew Peel, Helmut Clemens
Hot Deformation Of Cast And Extruded Tial: An In-Situ Diffraction Study, Thomas Schmoelzer, Klaus-Dieter Liss, Svea Mayer, Kun Yan, Mark H. Reid, Rian J. Dippenaar, Matthew Peel, Helmut Clemens
Faculty of Engineering - Papers (Archive)
Intermetallic TiAl alloys are a class of innovative high-temperature materials which are developed to replace the substantially denser Ni-base alloys in low-pressure turbine blades of jet engines. By streamlining the production process of these parts, a substantial decrease in production costs can be achieved. To this end, a profound knowledge of the microstructural processes occurring during hot deformation is a prerequisite. To investigate the microstructural development during forming operations, cast and extruded as well as only cast specimens were hot-deformed and the microstructural development investigated in-situ by means of a novel diffraction method. This powder diffraction method utilizes the behavior …
Study On Surface Roughness And Friction During Hot Rolling Of Stainless Steel 301, Dongbin Wei, Zhengyi Jiang, Junxia Huang, Aiwen Zhang, Xu Shi, Sihai Jiao
Study On Surface Roughness And Friction During Hot Rolling Of Stainless Steel 301, Dongbin Wei, Zhengyi Jiang, Junxia Huang, Aiwen Zhang, Xu Shi, Sihai Jiao
Faculty of Engineering and Information Sciences - Papers: Part A
A well-defined boundary condition is important for generating an accurate model for simulating metal forming process. It is important to characterize the features of the oxide scale in hot rolling of stainless steel strip. Short time oxidation tests in humid air with water vapor content of 7.0 vol. % were carried out using Gleeble 3500 thermo-mechanical simulator. The deformation, surface morphology of oxide scale, and the friction in hot rolling were studied by conducting hot rolling tests. The results show that the surface roughness decreases with an increase of reduction. The effect of oxide scale on friction and surface roughness …
The Benefits Of Introducing Electronic Health Records In Residential Aged Care Facilities: A Multiple Case Study, Yiting Zhang, Ping Yu, Jun Shen
The Benefits Of Introducing Electronic Health Records In Residential Aged Care Facilities: A Multiple Case Study, Yiting Zhang, Ping Yu, Jun Shen
Faculty of Engineering and Information Sciences - Papers: Part A
Purpose: Information and communications technology solutions have been introduced into the residential aged care system in order to improve the effectiveness and efficiency of aged care, however to date, the actual benefits have not been systematically analysed. The aim of this study was to identify the benefits of electronic health records (EHR) in residential aged care services and to examine how the benefits have been achieved. Method: A qualitative interview study was conducted in nine residential aged care facilities (RACFs) belonging to three organisations in the Australian Capital Territory (ACT), New South Wales (NSW) and Queensland, Australia. A longitudinal investigation …
A Comparison Study Of Chain-Die Forming And Roll Forming By Forming A Top Hat Section, Yuankun Zhang, Shichao Ding
A Comparison Study Of Chain-Die Forming And Roll Forming By Forming A Top Hat Section, Yuankun Zhang, Shichao Ding
Faculty of Engineering and Information Sciences - Papers: Part A
Chain-die Forming, a novel sheet metal forming method, has been proposed and developed recently to overcome the problems that arose in roll forming. As an extension to roll forming, Chain-die Forming has been proposed to elongate the deformation length by increasing the virtual roll radii, and employing discrete profiled die-blocks which move on a track board with the desired large radii to im-plement or simulate the rotation of the virtual large rolls. The roll radii are so large and the forming length is so long that all redundant strain components occurring in roll forming are significantly reduced or even eliminated.
Dynamic Characteristics Of A Hybrid Microgrid With Inverter And Non- Inverter Interfaced Renewable Energy Sources: A Case Study, A V. Jayawardena, L G. Meegahapola, S Perera, D A. Robinson
Dynamic Characteristics Of A Hybrid Microgrid With Inverter And Non- Inverter Interfaced Renewable Energy Sources: A Case Study, A V. Jayawardena, L G. Meegahapola, S Perera, D A. Robinson
Faculty of Engineering and Information Sciences - Papers: Part A
Microgrids are becoming important constituents of electric power distribution networks. Microgrids are typically comprised of both inverter interfaced (e.g. double-fed induction generator (DFIG), solar-photovoltaic (PV) system) and non-inverter interfaced (e.g. synchronous generator) renewable energy generators (REGs), hence their dynamic characteristics are significantly different from the conventional grids comprised of centralised synchronous generators. Different inherent characteristics of REGs, power dispatch levels, relative REG capacities, and external grid characteristics are some of the important features of significant interest in relation to microgrid dynamic behaviour. For this study a microgrid model was developed in DIgSILENT Power Factory based on the IEEE-13 bus system …
Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer
Hollow Nitrogen Containing Core/Shell Fibrous Carbon Nanomaterials As Support To Platinum Nanocatalysts And Their Tem Tomography Study, Cuifeng Zhou, Zongwen Liu, Xusheng Du, David Rg Mitchell, Yiu-Wing Mai, Yushan Yan, Simon Peter Ringer
Australian Institute for Innovative Materials - Papers
Core/shell nanostructured carbon materials with carbon nanofiber (CNF) as the core and a nitrogen (N)-doped graphitic layer as the shell were synthesized by pyrolysis of CNF/polyaniline (CNF/PANI) composites prepared by in situ polymerization of aniline on CNFs. High-resolution transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared and Raman analyses indicated that the PANI shell was carbonized at 900 degress C. Platinum (Pt) nanoparticles were reduced by formic acid with catalyst supports. Compared to the untreated CNF/ PANI composites, the carbonized composites were proven to be better supporting materials for the Pt nanocatalysts and showed superior performance as catalyst …
Physicochemical Study Of Spiropyran-Terthiophene Derivatives: Photochemistry And Thermodynamics, Michele Zanoni, Simon Coleman, Kevin J. Fraser, Robert P. Byrne, Klaudia K. Wagner, Sanjeev Gambhir, David L. Officer, Gordon G. Wallace, D Diamond
Physicochemical Study Of Spiropyran-Terthiophene Derivatives: Photochemistry And Thermodynamics, Michele Zanoni, Simon Coleman, Kevin J. Fraser, Robert P. Byrne, Klaudia K. Wagner, Sanjeev Gambhir, David L. Officer, Gordon G. Wallace, D Diamond
Australian Institute for Innovative Materials - Papers
The photochemistry and thermodynamics of two terthiophene (TTh) derivatives bearing benzospiropyran (BSP) moieties, 1-(3,3''-dimethylindoline-6'-nitrobenzospiropyranyl)-2-ethyl 4,4''-didecyloxy-2,2':5',2''-terthiophene-30-acetate (BSP-2) and 1-(3,3''-dimethylindoline-6'- nitrobenzospiropyranyl)-2-ethyl 4,4''-didecyloxy-2,2':5',2''-terthiophene-30-carboxylate (BSP-3), differing only by a single methylene spacer unit, have been studied. The kinetics of photogeneration of the equivalent merocyanine (MC) isomers (MC-2 and MC-3, respectively), the isomerisation properties of MC-2 and MC-3, and the thermodynamic parameters have been studied in acetonitrile, and compared to the parent, non-TTh-functionalised, benzospiropyran derivative, BSP-1. Despite the close structural similarity of BSP-2 and BSP-3, their physicochemical properties were found to differ significantly; examples include activation energies (Ea(MC-2) = 75.05 kJ mol-1, …
Methane Activation On Fe4 Cluster: A Density Functional Theory Study, Qiao Sun, Zhen Li, Meng Wang, Aijun Du, Sean C. Smith
Methane Activation On Fe4 Cluster: A Density Functional Theory Study, Qiao Sun, Zhen Li, Meng Wang, Aijun Du, Sean C. Smith
Australian Institute for Innovative Materials - Papers
We report a comprehensive theoretical study on reaction of methane by Fe4 cluster. This Letter gains insight into the mechanism of the reaction and indicate the Fe4 cluster has strong catalytic effect on the activation reaction of methane. In detail, the results show the cleavage of the first C-H bond is both an energetically and kinetically favourable process and the breaking of the second C-H is the rate-determining step. Moreover, our Letter demonstrates that the different cluster size of iron can not only determine the catalytic activity of methane but also control the product selectivity.
Parameters Controlling Emission Of Terahertz Frequency Electromagnetic Radiation From Inas And Gaas: An Ensemble Monte Carlo Simulation Study, David Laurence Cortie, Roger A. Lewis
Parameters Controlling Emission Of Terahertz Frequency Electromagnetic Radiation From Inas And Gaas: An Ensemble Monte Carlo Simulation Study, David Laurence Cortie, Roger A. Lewis
Australian Institute for Innovative Materials - Papers
The generation, manipulation and detection of terahertz-frequency electromagnetic radiation are topics of great current theoretical and experimental interest. In particular, the coherent generation and detection of ultrashort pulses of terahertz radiation has opened up the field of terahertz time-domain spectroscopy, which permits the simultaneous measurement of amplitude and phase of the terahertz electric field. In this paper, the emission of terahertz radiation from bare semiconductor surfaces following photoexcitation by ultrashort pulses of near-infrared radiation is studied using ensemble Monte Carlo simulations. The simulation allows us to examine separately distinct scattering mechanisms and to vary the materials parameters of bandgap, absorption …