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Full-Text Articles in Social and Behavioral Sciences

A Simple Proof Of Euler's Continued Fraction Of E^{1/M}, Joseph Tonien Jan 2016

A Simple Proof Of Euler's Continued Fraction Of E^{1/M}, Joseph Tonien

Faculty of Engineering and Information Sciences - Papers: Part A

A continued fraction is an expression of the form

f0+ g0

f1+g1

f2+g2

and we will denote it by the notation [f0, (g0, f1), (g1, f2), (g2, f3), … ]. If the numerators gi are all equal to 1 then we will use a shorter notation [f0, f1, f2, f3, … ]. A simple continued fraction is a continued fraction with all the …


Effects Of Salinity Build-Up On The Performance Of An Anaerobic Membrane Bioreactor Regarding Basic Water Quality Parameters And Removal Of Trace Organic Contaminants, Xiaoye Song, James A. Mcdonald, William E. Price, Stuart J. Khan, Faisal I. Hai, Hao H. Ngo, Wenshan Guo, Long D. Nghiem Jan 2016

Effects Of Salinity Build-Up On The Performance Of An Anaerobic Membrane Bioreactor Regarding Basic Water Quality Parameters And Removal Of Trace Organic Contaminants, Xiaoye Song, James A. Mcdonald, William E. Price, Stuart J. Khan, Faisal I. Hai, Hao H. Ngo, Wenshan Guo, Long D. Nghiem

Faculty of Engineering and Information Sciences - Papers: Part A

The effects of elevated inorganic salt concentration on anaerobic membrane bioreactor (AnMBR) treatment regarding basic biological performance and trace organic contaminant (TrOC) removal were investigated. A set of 33 TrOCs were selected to represent pharmaceuticals, steroids, and pesticides in municipal wastewater. Results show potential adverse effects of increase in the bioreactor salinity to 15 g/L (as NaCl) on the performance of AnMBR with respect to chemical oxygen demand removal, biogas production, and the removal of most hydrophilic TrOCs. Furthermore, a decrease in biomass production was observed as salinity in the bioreactor increased. The removal of most hydrophobic TrOCs was high …


Statistical Bias And Variance For The Regularized Inverse Problem: Application To Space-Based Atmospheric Co2 Retrievals, Noel A. Cressie, R Wang, Michael M. Smyth, Charles E. Miller Jan 2016

Statistical Bias And Variance For The Regularized Inverse Problem: Application To Space-Based Atmospheric Co2 Retrievals, Noel A. Cressie, R Wang, Michael M. Smyth, Charles E. Miller

Faculty of Engineering and Information Sciences - Papers: Part A

Remote sensing of the atmosphere is typically achieved through measurements that are high-resolution radiance spectra. In this article, our goal is to characterize the first-moment and second-moment properties of the errors obtained when solving the regularized inverse problem associated with space-based atmospheric CO2 retrievals, specifically for the dry air mole fraction of CO2 in a column of the atmosphere. The problem of estimating (or retrieving) state variables is usually ill posed, leading to a solution based on regularization that is often called Optimal Estimation (OE). The difference between the estimated state and the true state is defined to be the …


Student Rules: Exploring Patterns Of Students' Computer-Efficacy And Engagement With Digital Technologies In Learning, Sarah Katherine Howard, Jun Ma, Jie Yang Jan 2016

Student Rules: Exploring Patterns Of Students' Computer-Efficacy And Engagement With Digital Technologies In Learning, Sarah Katherine Howard, Jun Ma, Jie Yang

Faculty of Engineering and Information Sciences - Papers: Part A

Teachers' beliefs about students' engagement in and knowledge of digital technologies will affect technologically integrated learning designs. Over the past few decades, teachers have tended to feel that students were confident and engaged users of digital technologies, but there is a growing body of research challenging this assumption. Given this disparity, it is necessary to examine students' confidence and engagement using digital technologies to understand how differences may affect experiences in technologically integrated learning. However, the complexity of teaching and learning can make it difficult to isolate and study multiple factors and their effects. This paper proposes the use of …


Ambient Controlled Synthesis Of Advanced Core-Shell Plasmonic Ag@Zno Photocatalysts, Jinyan Xiong, Qiao Sun, Jun Chen, Zhen Li, S X. Dou Jan 2016

Ambient Controlled Synthesis Of Advanced Core-Shell Plasmonic Ag@Zno Photocatalysts, Jinyan Xiong, Qiao Sun, Jun Chen, Zhen Li, S X. Dou

Faculty of Engineering and Information Sciences - Papers: Part A

Plasmonic Ag@ZnO core-shell hybrids, including hetero-nanowires and hetero-nanoparticles, have been synthesized at room temperature for application in photocatalysis. The morphology, size, crystal structure, and composition of the products were investigated by X-ray diffraction, scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, and ultraviolet-visible spectroscopy. It was found the concentration of Zn(NO3)2·6H2O and the amount of water play crucial roles in the formation of Ag@ZnO core-shell hybrids. The resultant Ag@ZnO core-shell hybrids exhibit much higher photocatalytic activity and stability towards degradation of organic contaminants than pure ZnO nanocrystals under solar light irradiation. The one-dimensional (1D) core-shell hetero-nanowires prepared under optimal conditions …


A Review On Numerical Solutions To Self-Heating Of Coal Stockpile: Mechanism, Theoretical Basis, And Variable Study, Jian Zhang, Ting X. Ren, Yuntao Liang, Zhongwei Wang Jan 2016

A Review On Numerical Solutions To Self-Heating Of Coal Stockpile: Mechanism, Theoretical Basis, And Variable Study, Jian Zhang, Ting X. Ren, Yuntao Liang, Zhongwei Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Self-heating or even spontaneous combustion of stockpiled coal, which is likely to outbreak under favourable circumstances during its transport, process, and storage, is a long-standing thermal dynamic hazard. This hazard is harmful in diverse aspects: causing loss of coal resource and caking property, raising safety concerns upon occurrence of open fire, and giving off noxious/greenhouse effect gases. Due to the complexity of involved physical process (e.g. heat and mass transport) and chemical process (e.g. coal oxidation), formulating an analytical solution to the problem with or even without a transient approach would be a daunting task and the problem is thus …


Functorial Properties Of Putnam's Homology Theory For Smale Spaces, Robin J. Deeley, D. Brady Killough, Michael F. Whittaker Jan 2016

Functorial Properties Of Putnam's Homology Theory For Smale Spaces, Robin J. Deeley, D. Brady Killough, Michael F. Whittaker

Faculty of Engineering and Information Sciences - Papers: Part A

We investigate functorial properties of Putnam's homology theory for Smale spaces. Our analysis shows that the addition of a conjugacy condition is necessary to ensure functoriality. Several examples are discussed that elucidate the need for our additional hypotheses. Our second main result is a natural generalization of Putnam's Pullback Lemma from shifts of finite type to non-wandering Smale spaces.


Quantum Private Set Intersection Cardinality And Its Application To Anonymous Authentication, Runhua Shi, Yi Mu, Hong Zhong, Shun Zhang, Jie Cui Jan 2016

Quantum Private Set Intersection Cardinality And Its Application To Anonymous Authentication, Runhua Shi, Yi Mu, Hong Zhong, Shun Zhang, Jie Cui

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we proposed an unconditionally secure quantum Private Set Intersection Cardinality (PSI-CA) protocol. Compared with classical PSI-CA protocols, the proposed protocol can dramatically reduce the communication complexity, because it only requires O(1) communication cost, which is fully independent of the size of the sets. Furthermore, based on the proposed quantum PSI-CA protocol, we constructed a novel anonymous authentication scheme. This scheme can not only achieve two basic secure goals: secure authentication and anonymity, but can also dynamically update the authorized clients. When revoking any authorized client or adding a new client, it only needs to simply compute several …


Outlier Robust Small-Area Estimation Under Spatial Correlation, Timo Schmid, Nikos Tzavidis, Ralf Munnich, Raymond L. Chambers Jan 2016

Outlier Robust Small-Area Estimation Under Spatial Correlation, Timo Schmid, Nikos Tzavidis, Ralf Munnich, Raymond L. Chambers

Faculty of Engineering and Information Sciences - Papers: Part A

Modern systems of official statistics require the estimation and publication of business statistics for disaggregated domains, for example, industry domains and geographical regions. Outlier robust methods have proven to be useful for small-area estimation. Recently proposed outlier robust model-based small-area methods assume, however, uncorrelated random effects. Spatial dependencies, resulting from similar industry domains or geographic regions, often occur. In this paper, we propose an outlier robust small-area methodology that allows for the presence of spatial correlation in the data. In particular, we present a robust predictive methodology that incorporates the potential spatial impact from other areas (domains) on the small …


Modelling Water Molecules Inside Cyclic Peptide Nanotubes, Prangsai Tiangtrong, Ngamta Thamwattana, Duangkamon Baowan Jan 2016

Modelling Water Molecules Inside Cyclic Peptide Nanotubes, Prangsai Tiangtrong, Ngamta Thamwattana, Duangkamon Baowan

Faculty of Engineering and Information Sciences - Papers: Part A

Cyclic peptide nanotubes occur during the selfassembly process of cyclic peptides. Due to the ease of synthesis and ability to control the properties of outer surface and inner diameter by manipulating the functional side chains and the number of amino acids, cyclic peptide nanotubes have attracted much interest from many research areas. A potential application of peptide nanotubes is their use as artificial transmembrane channels for transporting ions, biomolecules and waters into cells. Here, we use the Lennard-Jones potential and a continuum approach to study the interaction of a water molecule in a cyclo[(-DAla- L-Ala)4-] peptide nanotube. Assuming that each …


Threshold Broadcast Encryption With Keyword Search, Shiwei Zhang, Yi Mu, Guomin Yang Jan 2016

Threshold Broadcast Encryption With Keyword Search, Shiwei Zhang, Yi Mu, Guomin Yang

Faculty of Engineering and Information Sciences - Papers: Part A

Many users store their data in a cloud, which might not be fully trusted, for the purpose of convenient data access and sharing. For efficiently accessing the stored data, keyword search can be performed by the cloud server remotely with a single query from the user. However, the cloud server cannot directly search the data if it is encrypted. One of solutions could be to allow the user to download the encrypted data, in order to carry out a search; however, it might consume huge network bandwidth. To solve this problem, the notion of keyword search on encrypted data (searchable …


The Impact Of Electronic Health Records On Risk Management Of Information Systems In Australian Residential Aged Care Homes, Tao Jiang, Ping Yu, David M. Hailey, Jun Ma, Jie Yang Jan 2016

The Impact Of Electronic Health Records On Risk Management Of Information Systems In Australian Residential Aged Care Homes, Tao Jiang, Ping Yu, David M. Hailey, Jun Ma, Jie Yang

Faculty of Engineering and Information Sciences - Papers: Part A

To obtain indications of the influence of electronic health records (EHR) in managing risks and meeting information system accreditation standard in Australian residential aged care (RAC) homes. The hypothesis to be tested is that the RAC homes using EHR have better performance in meeting information system standards in aged care accreditation than their counterparts only using paper records for information management. Content analysis of aged care accreditation reports from the Aged Care Standards and Accreditation Agency produced between April 2011 and December 2013. Items identified included types of information systems, compliance with accreditation standards, and indicators of failure to meet …


Drained And Undrained Shear Behavior Of Compacted Coal Wash, Ana Heitor, Buddhima Indraratna, Chazath Kaliboullah, Cholachat Rujikiatkamjorn, Geoffrey Mcintosh Jan 2016

Drained And Undrained Shear Behavior Of Compacted Coal Wash, Ana Heitor, Buddhima Indraratna, Chazath Kaliboullah, Cholachat Rujikiatkamjorn, Geoffrey Mcintosh

Faculty of Engineering and Information Sciences - Papers: Part A

Coal wash is a granular waste material that is readily available in the vicinity of coal mining operations. While its potential use in structural fills has been recognized in the past, the effects of particle breakage on the geomechanical performance of the material have not been thoroughly investigated. In this paper, an experimental study on a selected coal wash is undertaken to characterize the influence of compaction and particle breakage on its corresponding stress-strain behavior. Particular emphasis is given to the role of compaction energy level and associated breakage incurred during compaction on the drained and undrained shearing behavior. The …


Shape Optimisation Of Cold-Formed Steel Columns With Manufacturing Constraints Using The Hough Transform, Bin Wang, Benoit P. Gilbert, Adrien M. Molinier, Hong Guan, Lip H. Teh Jan 2016

Shape Optimisation Of Cold-Formed Steel Columns With Manufacturing Constraints Using The Hough Transform, Bin Wang, Benoit P. Gilbert, Adrien M. Molinier, Hong Guan, Lip H. Teh

Faculty of Engineering and Information Sciences - Papers: Part A

This paper introduces manufacturing constraints into a recently developed evolutionary algorithm for shape optimisation of CFS profiles. The algorithm is referred to as "self-shape optimisation" and uses Genetic Algorithm (GA) together with the Augmented Lagrangian (AL) method to avoid ill-conditioned problems. Simple manufacturing rules derived from the limitations of current cold-forming processes, i.e. a limited ability to form continuously curved surfaces without discrete bends, are described in the paper and incorporated into the algorithm. The Hough transform is used to detect straight lines and transform arbitrarily drawn cross-sections into manufacturable ones. Firstly, the algorithm is verified against a known optimisation …


Robustness Of Ipsa Optimized High-Dose-Rate Prostate Brachytherapy Treatment Plans To Catheter Displacements, Joel Poder, May Whitaker Jan 2016

Robustness Of Ipsa Optimized High-Dose-Rate Prostate Brachytherapy Treatment Plans To Catheter Displacements, Joel Poder, May Whitaker

Faculty of Engineering and Information Sciences - Papers: Part A

Purpose: Inverse planning simulated annealing (IPSA) optimized brachytherapy treatment plans are characterized with large isolated dwell times at the first or last dwell position of each catheter. The potential of catheter shifts relative to the target and organs at risk in these plans may lead to a more significant change in delivered dose to the volumes of interest relative to plans with more uniform dwell times. Material and methods: This study aims to determine if the Nucletron Oncentra dwell time deviation constraint (DTDC) parameter can be optimized to improve the robustness of high-dose-rate (HDR) prostate brachytherapy plans to catheter displacements. …


Membrane Distillation And Membrane Electrolysis Of Coal Seam Gas Reverse Osmosis Brine For Clean Water Extraction And Naoh Production, Hung Duong, Mikel C. Duke, Stephen Gray, Bart Nelemans, Long D. Nghiem Jan 2016

Membrane Distillation And Membrane Electrolysis Of Coal Seam Gas Reverse Osmosis Brine For Clean Water Extraction And Naoh Production, Hung Duong, Mikel C. Duke, Stephen Gray, Bart Nelemans, Long D. Nghiem

Faculty of Engineering and Information Sciences - Papers: Part A

Membrane distillation (MD) and membrane electrolysis (ME) were evaluated for simultaneous fresh water extraction and NaOH production from a mixture of NaCl and NaHCO3 to simulate the composition of coal seam gas (CSG) reverse osmosis (RO) brine. Experimental results demonstrate the potential of MD for producing fresh water and simultaneously concentrating CSG RO brine prior to the ME process. MD water flux was slightly reduced by the increased feed salinity and the decomposition of bicarbonate to CO2 during the concentration of CSG RO brine. MD operation of CSG RO brine at a concentration factor of 10 (90% water recovery) was …


Pore Pressure Based Method To Quantify Smear Around A Vertical Drain, Kirti Choudhary, Buddhima Indraratna, Cholachat Rujikiatkamjorn Jan 2016

Pore Pressure Based Method To Quantify Smear Around A Vertical Drain, Kirti Choudhary, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

Radial consolidation testing of Ballina clay (New South Wales, Australia) was carried out using a large-scale consolidometer 650 mm in diameter. In this study, the characteristics of the smear zone were evaluated on the basis of hydraulic gradient changes derived from the measured excess pore pressure data in the radial direction. The extent of the smear zone determined using this technique is compared with past approaches, where the variations in water content and lateral permeability were adopted to evaluate smear. The approach proposed herein based on the change of hydraulic gradient coincides with the previous two methods, and the smear …


Orthogonal Polynomial-Based Nonlinearity Modeling And Mitigation For Led Communications, Weikang Zhao, Qinghua Guo, Jun Tong, Jiangtao Xi, Yanguang Yu, Pingjuan Niu, Xiaohong Sun Jan 2016

Orthogonal Polynomial-Based Nonlinearity Modeling And Mitigation For Led Communications, Weikang Zhao, Qinghua Guo, Jun Tong, Jiangtao Xi, Yanguang Yu, Pingjuan Niu, Xiaohong Sun

Faculty of Engineering and Information Sciences - Papers: Part A

The light-emitting diode (LED) is the major source of nonlinearity in LED communications, and the nonlinearity needs to be effectively modeled and thereby mitigated through predistortion or postdistortion to avoid degradation of communication performance. A memory polynomial is often used for LED nonlinearity modeling and mitigation in the literature. However, the estimation of memory polynomial coefficients suffers from numerical instability, resulting in inaccurate modeling and poor performance in nonlinearity mitigation. In this paper, we propose an orthogonal polynomial-based nonlinearity modeling and mitigation technique for LED communications with pulse amplitude modulation (PAM) signaling and show that the proposed technique significantly outperforms …


Iterates Of Holomorphic Self-Maps On Pseudoconvex Domains Of Finite And Infinite Type In Cn, Tran Vu Khanh, Ninh Van Thu Jan 2016

Iterates Of Holomorphic Self-Maps On Pseudoconvex Domains Of Finite And Infinite Type In Cn, Tran Vu Khanh, Ninh Van Thu

Faculty of Engineering and Information Sciences - Papers: Part A

Using the lower bounds on the Kobayashi metric established by the first author, we prove a Wolff-Denjoy-type theorem for a very large class of pseudoconvex domains in Cn. This class includes many pseudoconvex domains of finite type and infinite type.


Soft Soil Stabilisation Through Native Vegetation Along Rail Corridors, Udeshini Pathirage, Buddhima Indraratna, Ana Heitor Jan 2016

Soft Soil Stabilisation Through Native Vegetation Along Rail Corridors, Udeshini Pathirage, Buddhima Indraratna, Ana Heitor

Faculty of Engineering and Information Sciences - Papers: Part A

The 'green corridor' concept along the railway lines is an emerging research area in bio-engineering as form of subgrade soil stabilization. Native trees grown along rail corridors increase the matric suction of the subgrade through the root water uptake associated with the evapo-transpiration by the tree canopy. One of the most important aspects in subsoil improvement through native vegetation is the effect of osmotic suction attributed to solute uptake by active root hairs. The current study offers to capture the effect of matric and osmotic suction to overcome the existing empirical relations which are applicable mainly for site-specific controlled conditions. …


General Purpose Cement With Increased Limestone Content In Australia, Iman Mohammadi, Warren J. South Jan 2016

General Purpose Cement With Increased Limestone Content In Australia, Iman Mohammadi, Warren J. South

Faculty of Engineering and Information Sciences - Papers: Part A

This paper discusses the effects of an increase in the maximum allowable limestone content of general purpose (GP) cement from 7.5 up to 12%. The substitution of a higher content of clinker with limestone will allow for a lower embodied energy and emissions associated with the manufacture of GP cement. Fresh and hardened properties of normal-grade concrete (N20 and N32) prepared with GP cement containing limestone contents in the range of 5 to 12% were investigated. The compliance of test results were checked and confirmed against the requirements of cement and concrete specifications. In addition, the test results were statistically …


Edit Distance Based Encryption And Its Application, Phuong Viet Xuan Tran, Guomin Yang, Willy Susilo, Kaitai Liang Jan 2016

Edit Distance Based Encryption And Its Application, Phuong Viet Xuan Tran, Guomin Yang, Willy Susilo, Kaitai Liang

Faculty of Engineering and Information Sciences - Papers: Part A

Edit distance, also known as Levenshtein distance, is a very useful tool to measure the similarity between two strings. It has been widely used in many applications such as natural language processing and bioinformatics. In this paper, we introduce a new type of fuzzy public key encryption called Edit Distance-based Encryption (EDE). In EDE, the encryptor can specify an alphabet string and a threshold when encrypting a message, and a decryptor can obtain a decryption key generated from another alphabet string, and the decryption will be successful if and only if the edit distance between the two strings is within …


Contraction Of Convex Surfaces By Nonsmooth Functions Of Curvature, Ben H. Andrews, James A. Mccoy Jan 2016

Contraction Of Convex Surfaces By Nonsmooth Functions Of Curvature, Ben H. Andrews, James A. Mccoy

Faculty of Engineering and Information Sciences - Papers: Part A

We consider the motion of convex surfaces with normal speed given by arbitrary strictly monotone, homogeneous degree one functions of the principal curvatures (with no further smoothness assumptions). We prove that such processes deform arbitrary uniformly convex initial surfaces to points in finite time, with spherical limiting shape. This result was known previously only for smooth speeds. The crucial new ingredient in the argument, used to prove convergence of the rescaled surfaces to a sphere without requiring smoothness of the speed, is a surprising hidden divergence form structure in the evolution of certain curvature quantities.


Cloud Computing Services Adoption In Australian Smes: A Firm-Level Investigation, Salim Al Isma'ili, Mengxiang Li, Qiang He, Jun Shen Jan 2016

Cloud Computing Services Adoption In Australian Smes: A Firm-Level Investigation, Salim Al Isma'ili, Mengxiang Li, Qiang He, Jun Shen

Faculty of Engineering and Information Sciences - Papers: Part A

Cloud computing services can boost the competitiveness of Small and Medium-sized Enterprises (SMEs) and leverage countries' economies. In the Australian context, there is an emerging trend that SMEs begin to embrace cloud technology in their traditional business activities. However, prior studies did not pay much attention to investigating the factors that influence the cloud computing adoption among Australian SMEs. To fill the research gap, this paper investigates the influential factors that affect the decision on adopting cloud computing services for Australian SMEs. Protocol data collected from fifteen firm-level semi-structured interviews with practitioners are presented and discussed. The protocol analysis indicates …


Cloud Computing Adoption Determinants: An Analysis Of Australian Smes, Salim Al Isma'ili, Mengxiang Li, Jun Shen, Qiang He Jan 2016

Cloud Computing Adoption Determinants: An Analysis Of Australian Smes, Salim Al Isma'ili, Mengxiang Li, Jun Shen, Qiang He

Faculty of Engineering and Information Sciences - Papers: Part A

In Australia, there is an emerging tendency among SMEs towards the adoption of cloud computing. However, there are limited studies investigating the factors that influence cloud computing adoption within Australian SMEs. To fill the research vacuum, we developed a research model based on the diffusion of innovation theory (DOI), the technology-organisation-environment (TOE) framework, and our prior exploratory study to investigate the determinants that influence the adoption of cloud computing. An organizational-level survey was conducted across Australia to collect data from technology decision makers in SMEs. Data collected from 203 firms are used to test the related hypotheses. This study contributes …


Implementation Of Health Technology Assessment Work In A Hospital In Kazakhstan, Lyazzat Kosherbayeva, David M. Hailey, Kural Kurakbaev, Aleksey Tsoy, Ormanbek Zhuzzhanov, Abilay Donbay, Ainur Kumar, Kamalzhan Nadyrov Jan 2016

Implementation Of Health Technology Assessment Work In A Hospital In Kazakhstan, Lyazzat Kosherbayeva, David M. Hailey, Kural Kurakbaev, Aleksey Tsoy, Ormanbek Zhuzzhanov, Abilay Donbay, Ainur Kumar, Kamalzhan Nadyrov

Faculty of Engineering and Information Sciences - Papers: Part A

Objectives: The aim of this study was to implement health technology assessment (HA) in the First General City Hospital in Astana, Kazakhstan. Methods: We organized trainings to familiarize hospital staff with the purpose and details of HTA. An HTA committee was established, with representation from hospital physicians and managers, and criteria for prioritization of health technologies determined. Clinical departments of the hospital were asked to prepare applications for new technologies for their services. Results: The HTA committee reviewed five applications and selected a technology from one of these, on single incision laparoscopic surgery (SILS), for assessment. A short HTA report …


Performance Improvement Of Rail Track Substructure Using Artificial Inclusions - Experimental And Numerical Studies, Buddhima Indraratna, Sanjay Nimbalkar, Ngoc Trung Ngo, Tim Neville Jan 2016

Performance Improvement Of Rail Track Substructure Using Artificial Inclusions - Experimental And Numerical Studies, Buddhima Indraratna, Sanjay Nimbalkar, Ngoc Trung Ngo, Tim Neville

Faculty of Engineering and Information Sciences - Papers: Part A

Large and frequent loads from heavy freight and passenger trains often lead to the progressive track deterioration. The excessive deformation and degradation of ballast and unacceptable differential settlement of track and/or pumping of underlying soft subgrade soils necessitates frequent and costly track maintenance. However, artificial inclusions such as geogrids and shockmats can mitigate ballast degradation and improve track performance. A quantitative assessment of the influence of breakage, fouling, and the effects of artificial inclusions on the shear behaviour of ballast can be performed either experimentally or numerically. Numerical modelling can simulate these aspects subject to various types of loading and …


Determination Of Stress State In Rock Mass Using Strain Gauge Probes Ccbo, Petr Waclawik, Stas Lubomir, Jan Nemcik, Petr Konicek, Tomas Kalab Jan 2016

Determination Of Stress State In Rock Mass Using Strain Gauge Probes Ccbo, Petr Waclawik, Stas Lubomir, Jan Nemcik, Petr Konicek, Tomas Kalab

Faculty of Engineering and Information Sciences - Papers: Part A

The strain gauge probes of different construction are typically used for determination of stress state rock mass. The modified overcoring method known as the Compact Conical ended Borehole Overcoring method (CCBO) for stress state determination in rock mass was designed in Institute of Geonics of the CAS (IGN) in cooperation with Kumamoto University in Japan. The implemented adjustment of the overcoring method consists mainly in omitting the overcoring phase (stress relief phase). The probe is glued directly to the conically shaped end of a borehole. The data logger located within the conical probe enables continual strain monitoring directly in the …


An Elasto-Plastic Method For Analysing The Deformation Of The Railway Ballast, Qideng Sun, Buddhima Indraratna, Sanjay Nimbalkar Jan 2016

An Elasto-Plastic Method For Analysing The Deformation Of The Railway Ballast, Qideng Sun, Buddhima Indraratna, Sanjay Nimbalkar

Faculty of Engineering and Information Sciences - Papers: Part A

In this study, a series of monotonically drained triaxial tests were conducted using the large-scale cylindrical triaxial apparatus. The effect of particle breakage and confining pressure on the mechanical behaviour of ballast were investigated. Based on the experimental findings, mathematical expressions for critical state stress ratio and specific volume are proposed to incorporate the evolution of particle breakage during monotonic shearing. An elasto-plastic constitutive model is formulated within the critical state soil mechanics framework in order to capture the stress-strain behaviour and degradation of ballast. The non-linear variation of shear strength envelope at a given range of confining pressures is …


Mineral Phase Formation And Zinc Removal During Sintering Of Filter Cake Wastes, Zhe Wang, David J. Pinson, Sheng Chew, Brian J. Monaghan, Harold P. Rogers, Guangqing Zhang Jan 2016

Mineral Phase Formation And Zinc Removal During Sintering Of Filter Cake Wastes, Zhe Wang, David J. Pinson, Sheng Chew, Brian J. Monaghan, Harold P. Rogers, Guangqing Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

A large amount of filter cake wastes are produced from the gas cleaning systems of blast furnace (BF) ironmaking and basic oxygen furnace (BOF) steelmaking processes. The filter cake wastes cannot be directly recycled through the ironmaking process due to the high zinc contents and are therefore, predominantly, stockpiled. The storage of filter cake wastes presents a long- Term environmental issue but also an opportunity to extract or recover the iron content, motivating a search for processes or technologies to allow their cost-effective recycling. In this study, two filter cake wastes from BlueScope Ltd. were sintered at 1 100-1 300°C …