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Resilience And Sustainability In The Management Of Landslides, Phillip N. Flentje, Robin N. Chowdhury Jan 2018

Resilience And Sustainability In The Management Of Landslides, Phillip N. Flentje, Robin N. Chowdhury

Faculty of Engineering and Information Sciences - Papers: Part A

There are many regions worldwide which are susceptible to landslides, which cause loss of life and adverse impacts to infrastructure, environment and communities. Landslides are often triggered by exceptional rainfall and large-magnitude earthquakes. A range of strategies and methods have been developed to mitigate the occurrence of landslides and to reduce their impact, including risk to human safety. The adopted approaches and systems must be sustainable and resilient in relation to the communities that are at risk. This paper refers to an Australian regional case study of urban landslide management in the Wollongong region, New South Wales. The research carried ...


Residual Stress Effects On Fatigue Crack Growth From A T-Butt Weld Toe, Alan K. Hellier, H. Li, B. G. Prusty, G. M. Pearce, M. Reid, A. M. Paradowska Jan 2018

Residual Stress Effects On Fatigue Crack Growth From A T-Butt Weld Toe, Alan K. Hellier, H. Li, B. G. Prusty, G. M. Pearce, M. Reid, A. M. Paradowska

Faculty of Engineering and Information Sciences - Papers: Part A

A350 grade black mild steel is one of the most widely used structural materials in the world, being commonly found in buildings, bridges and offshore structures.Welding is commonly used to join two plates of structural steel and this often takes the form of a T-butt.In addition, other more complex geometrical joints are often simplified for stress analysis purposes by approximating them as 2-D T-butt plate models (e.g. skewed T-joints, cruciform welded joints, tubular welded joints, pipe–plate joints, etc.).However, all such welds are potentially susceptible to fatigue crack initiation and slow but accelerating growth arising as ...


Fracture Toughness Of Cast And Extruded Al6061/15%Al2o3p Metal Matrix Composites, Alan K. Hellier, A. G. Crosky, H. A. Hassan, J. J. Lewandowski Jan 2018

Fracture Toughness Of Cast And Extruded Al6061/15%Al2o3p Metal Matrix Composites, Alan K. Hellier, A. G. Crosky, H. A. Hassan, J. J. Lewandowski

Faculty of Engineering and Information Sciences - Papers: Part A

Particulate reinforced metal matrix composites (PRMMCs) are of interest owing to the low cost of their raw materials and their ease of fabrication, making them suitable for applications requiring relatively high-volume production. The improved properties of PRMMCs result from the addition of hard ceramic particles (such as Al2O3 or SiC); the size, shape, volume fraction, interfacial properties and distribution of these (together with the fabrication method) determine the mechanical behaviour of the composite. However, PRMMCs have inferior ductility, toughness and low-cycle fatigue properties compared with unreinforced alloys, often limiting their usefulness in practice. Reinforcements of between 15 volume % and 25 ...


Bots Without Borders: How Anonymous Accounts Hijack Political Debate, Katina Michael Jan 2017

Bots Without Borders: How Anonymous Accounts Hijack Political Debate, Katina Michael

Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.


Linearization Of Ebt3 Film Dose Response And Virtual Film Dosimetry For Sbrt Quality Assurance, Meng Cai, Ben Archibald-Heeren, Yang Wang, Peter E. Metcalfe Jan 2017

Linearization Of Ebt3 Film Dose Response And Virtual Film Dosimetry For Sbrt Quality Assurance, Meng Cai, Ben Archibald-Heeren, Yang Wang, Peter E. Metcalfe

Faculty of Engineering and Information Sciences - Papers: Part A

EBT3 film offers high spatial resolution and low energy dependence, making it a suitable choice for quality assurance where high dose gradients are present, such as the case for SBRT. This work presents a simple method to adjust scanner settings so that dose response becomes linear. This linearity eliminates the need to obtain a calibration curve and associated uncertainties in curve fitting. Relative dosimetry can be performed after dose normalization to a reference point. Linearity is also a more robust condition than calibration curve with respect to scanner warm-up conditions, resulting in reduced uncertainty in dose measurement. An in-house developed ...


Monte Carlo Characterisation Of The Dose Magnifying Glass For Proton Therapy Quality Assurance, Aaron Merchant, Susanna Guatelli, Marco Petasecca, Michael A. Jackson, Anatoly B. Rosenfeld Jan 2017

Monte Carlo Characterisation Of The Dose Magnifying Glass For Proton Therapy Quality Assurance, Aaron Merchant, Susanna Guatelli, Marco Petasecca, Michael A. Jackson, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part A

A Geant4 Monte Carlo simulation study was carried out to characterise a novel silicon strip detector, the Dose Magnifying Glass (DMG), for use in proton therapy Quality Assurance. We investigated the possibility to use DMG to determine the energy of the incident proton beam. The advantages of DMG are quick response, easy operation and high spatial resolution. In this work we theoretically proved that DMG can be used for QA in the determination of the energy of the incident proton beam, for ocular and prostate cancer therapy. The study was performed by means of Monte Carlo simulations Experimental measurements are ...


Selection Bias In The Reported Performances Of Ad Classification Pipelines, Alex F. Mendelson, Maria A. Zuluaga, Marco Lorenzi, Brian F. Hutton, Sebastien Ourselin Jan 2017

Selection Bias In The Reported Performances Of Ad Classification Pipelines, Alex F. Mendelson, Maria A. Zuluaga, Marco Lorenzi, Brian F. Hutton, Sebastien Ourselin

Faculty of Engineering and Information Sciences - Papers: Part A

The last decade has seen a great proliferation of supervised learning pipelines for individual diagnosis and prognosis in Alzheimer's disease. As more pipelines are developed and evaluated in the search for greater performance, only those results that are relatively impressive will be selected for publication. We present an empirical study to evaluate the potential for optimistic bias in classification performance results as a result of this selection. This is achieved using a novel, resampling-based experiment design that effectively simulates the optimisation of pipeline specifications by individuals or collectives of researchers using cross validation with limited data. Our findings indicate ...


Superior Mechanical Properties Of Microalloyed Steels Processed Via A New Technology Based On Austenite Conditioning Followed By Warm Deformation, Andrii Kostryzhev, Olexandra Marenych Jan 2017

Superior Mechanical Properties Of Microalloyed Steels Processed Via A New Technology Based On Austenite Conditioning Followed By Warm Deformation, Andrii Kostryzhev, Olexandra Marenych

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper we introduce the AC2WD-technology, which stands for Austenite Conditioning – Accelerated Cooling – Warm Deformation. This technology was tested in laboratory conditions using a Gleeble thermomechanical simulator. Two microalloyed steels processed via this technology have shown a superior combination of mechanical properties, compared to those obtained via the conventional thermomechanical processing routes.


Quantum Beam Science-Applications To Probe Or Influence Matter And Materials, Klaus-Dieter Liss Jan 2017

Quantum Beam Science-Applications To Probe Or Influence Matter And Materials, Klaus-Dieter Liss

Faculty of Engineering and Information Sciences - Papers: Part A

The concept of quantum beams unifies a multitude of different kinds of radiation that can be considered as both waves and particles, according to the quantum mechanical model. Examples include light, in the form of X-rays and synchrotron radiation, as well as neutrons, electrons, positrons, muons, protons, ions, and photons. While the past century saw the discovery of these types of radiation and particles along with the investigations of their physical properties and their fundamental interaction with matter, the current century focuses extensively on their applications to characterize and understand materials in their broadest context, under all imaginable conditions. X-rays ...


Equivalence And Stable Isomorphism Of Groupoids, And Diagonal-Preserving Stable Isomorphisms Of Graph C*-Algebras And Leavitt Path Algebras, Toke Meier Carlsen, Efren Ruiz, Aidan Sims Jan 2017

Equivalence And Stable Isomorphism Of Groupoids, And Diagonal-Preserving Stable Isomorphisms Of Graph C*-Algebras And Leavitt Path Algebras, Toke Meier Carlsen, Efren Ruiz, Aidan Sims

Faculty of Engineering and Information Sciences - Papers: Part A

We prove that ample groupoids with σ-compact unit spaces are equivalent if and only if they are stably isomorphic in an appropriate sense, and relate this to Matui's notion of Kakutani equivalence. We use this result to show that diagonal-preserving stable isomorphisms of graph C*-algebras or Leavitt path algebras give rise to isomorphisms of the groupoids of the associated stabilised graphs. We deduce that the Leavitt path algebras LZ(E2) and LZ(E2-) are not stably *-isomorphic.


Full Scale Co-Digestion Of Wastewater Sludge And Food Waste: Bottlenecks And Possibilities, Long D. Nghiem, Konrad Koch, David Bolzonella, Jörg E. Drewes Jan 2017

Full Scale Co-Digestion Of Wastewater Sludge And Food Waste: Bottlenecks And Possibilities, Long D. Nghiem, Konrad Koch, David Bolzonella, Jörg E. Drewes

Faculty of Engineering and Information Sciences - Papers: Part A

Wastewater treatment plants in many countries use anaerobic digesters for biosolids management and biogas generation. Opportunities exist to utilise the spare capacity of these digesters to co-digest food waste and sludge for energy recovery and a range of other economic and environmental benefits. This paper provides a critical perspective for full-scale implementation of co-digestion of food waste and wastewater sludge. Data compiled from full-scale facilities and the peer-reviewed literature revealed several key bottlenecks hindering full-scale implementation of co-digestion. Indeed, co-digestion applications remain concentrated mostly in countries or regions with favourable energy and waste management policies. Not all environmental benefits from ...


Innovative Detectors For Quality Assurance Dosimetry In Sbrt Of Stationary And Movable Targets, Matthew Newall, Marco Petasecca, Mitchell Duncan, Iolanda Fuduli, Khalsa Al Shukaili, Jeremy T. Booth, Paul J. Keall, Stephanie Corde, V Pereveratylo, Michael L. F Lerch, Anatoly B. Rosenfeld Jan 2017

Innovative Detectors For Quality Assurance Dosimetry In Sbrt Of Stationary And Movable Targets, Matthew Newall, Marco Petasecca, Mitchell Duncan, Iolanda Fuduli, Khalsa Al Shukaili, Jeremy T. Booth, Paul J. Keall, Stephanie Corde, V Pereveratylo, Michael L. F Lerch, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part A

The high spatial and temporal resolution 2D monolithic silicon detector arrays M512 and DUO for quality assurance (QA) in real time motion adaptive radiotherapy (ART) have been developed. The DUO array possesses a spatial resolution of 0.2 mm and has demonstrated agreement within 5% with EBT3 film measurements of 6MV linac beam profiles for field sizes 1 × 1 cm2 and SRS cone diameter 0.5 cm. Dynamic characterisation of the M512 for QA in real time ART evaluated the performance of M512 for small fields while the detector experiences periodic motion. It was demonstrated with M512 that MLC ...


Fracture Toughness Measurement For Aluminium 6061-T6 Using Notched Round Bars, Alan K. Hellier, P. P. Chaphalkar, B. G. Prusty Jan 2017

Fracture Toughness Measurement For Aluminium 6061-T6 Using Notched Round Bars, Alan K. Hellier, P. P. Chaphalkar, B. G. Prusty

Faculty of Engineering and Information Sciences - Papers: Part A

Current standard testing methods for determining plane strain fracture toughness (KIc), such as ASTM E399 and ASTM E1820, require a prior estimate of KIc, plus the specimens are large, involve a lot of machining and need fatigue pre-cracking. There is therefore a desire to develop new testing techniques which are simple, as well as cost and time effective. While the use of tensile notched round bars (NRB) test pieces is not novel, dating back to a conference paper by Brown in 1975, relatively few authors have so far attempted this.


Effect Of Scattered Electrons On The 'Magic Plate' Transmission Array Detector Response, Z A. Alrowaili, Michael L. F Lerch, Marco Petasecca, Martin G. Carolan, Anatoly B. Rosenfeld Jan 2017

Effect Of Scattered Electrons On The 'Magic Plate' Transmission Array Detector Response, Z A. Alrowaili, Michael L. F Lerch, Marco Petasecca, Martin G. Carolan, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part A

Transmission type detectors can provide a measure of the energy fluence and if they are real-time systems that do not significantly attenuate the radiation beam have a distinct advantage over the current method as Quality Assurance (QA) could in principle be done during the actual patient treatment. The use of diode arrays in QA holds much promise due to real-time operation and feedback when compared to other methods e.g. films which are not real-time. The goal of this work is to describe the characterization of the radiation response of a silicon diode array called the Magic Plate (MP) when ...


Development Of Microencapsulated Phase Change Material For Solar Thermal Energy Storage, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis Jan 2017

Development Of Microencapsulated Phase Change Material For Solar Thermal Energy Storage, Weiguang Su, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper a novel microencapsulated phase change material (MF-3) has been developed and tested for solar assisted hot water storage systems. Even though the morphology of the sample was affected by the type of emulsifier used for fabrication it recorded the highest energy storage capacity of 126 kJ/kg with encapsulation efficiency of 97.4% as compared with other developed samples. For the purpose of assessing its thermal effectiveness it was theoretically evaluated in a compacted fixed bed TES unit and found to be capable of achieving a higher energy storage density as well as relatively smaller physical storage ...


A Torsional Mre Joint For A C-Shaped Robotic Leg, M D. Christie, Shuaishuai Sun, Donghong Ning, Haiping Du, Shiwu Zhang, Weihua Li Jan 2017

A Torsional Mre Joint For A C-Shaped Robotic Leg, M D. Christie, Shuaishuai Sun, Donghong Ning, Haiping Du, Shiwu Zhang, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

Serving to improve stability and energy efficiency during locomotion, in nature, animals modulate their leg stiffness to adapt to their terrain. Now incorporated into many locomotive robot designs, such compliance control can enable disturbance rejection and improved transition between changing ground conditions. This paper presents a novel design of a variable stiffness leg utilizing a magnetorheological elastomer joint in a literal rolling spring loaded inverted pendulum (R-SLIP) morphology. Through the semi-active control of this hybrid permanent-magnet and coil design, variable stiffness is realized, offering a design which is capable of both softening and stiffening in an adaptive sort of way ...


Development Of A Dynamic Model For A Hybrid Photovoltaic Thermal Collector - Solar Air Heater With Fins, Wenke Fan, Georgios Kokogiannakis, Zhenjun Ma, Paul Cooper Jan 2017

Development Of A Dynamic Model For A Hybrid Photovoltaic Thermal Collector - Solar Air Heater With Fins, Wenke Fan, Georgios Kokogiannakis, Zhenjun Ma, Paul Cooper

Faculty of Engineering and Information Sciences - Papers: Part A

A dynamic model for a hybrid Photovoltaic Thermal Collector-Solar Air Heater (PVT-SAH) with longitudinal fins was developed to enable assessment of the potential of the system to provide high temperature outlet air (60-90 °C) under dynamic boundary conditions. The model description includes the method for discretising the system into a number of control volumes, the energy balance equations for each control volume and the implementation of the numerical solution. Model validation has been successfully undertaken by using empirical verification of model predictions with an experimental facility and by comparing the model outputs with the reference data from the literature. The ...


An Efficient And Provably Secure Rfid Grouping Proof Protocol, Shu Cheng, Vijay Varadharajan, Yi Mu, Willy Susilo Jan 2017

An Efficient And Provably Secure Rfid Grouping Proof Protocol, Shu Cheng, Vijay Varadharajan, Yi Mu, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part A

RFID Grouping proof convinces an offline verifier that multiple tags are simultaneously scanned. Various solutions have been proposed but most of them have security and privacy vulnerabilities. In this paper, we propose an elliptic-curve-based RFID grouping proof protocol. Our protocol is proven secure and narrow-strong private. We also demonstrate that our grouping proof can be batch verified to improve the efficiency for large-scale RFID systems and it is suitable for low-cost RFID tags.


Introducing Dynamic Dosimaging: Potential Applications For Mri-Linac, Peter E. Metcalfe, Sarah Alnaghy, Matthew Newall, Maegan Gargett, Mitchell Duncan, Gary P. Liney, Jarrad Begg, Bradley M. Oborn, Marco Petasecca, Michael L. F Lerch, Anatoly B. Rosenfeld Jan 2017

Introducing Dynamic Dosimaging: Potential Applications For Mri-Linac, Peter E. Metcalfe, Sarah Alnaghy, Matthew Newall, Maegan Gargett, Mitchell Duncan, Gary P. Liney, Jarrad Begg, Bradley M. Oborn, Marco Petasecca, Michael L. F Lerch, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part A

The new era of intra-fraction dose tracking in radiation therapy delivery demands new dosimetry methods, whereby a moving frame of reference as a function of time may be required. This introduces a new paradigm into radiation therapy dose verification. The term we propose to describe this is dynamic dosimaging, which by our definition is tracking the location of a dosimeter array in real time during on-line radiation dose acquisition.


History Of International Workshop On Mini-Micro- And Nano- Dosimetry (Mmnd) And Innovation Technologies In Radiation Oncology (Itro), Anatoly B. Rosenfeld, Marco Zaider, J Yamada, M Zelefsky Jan 2017

History Of International Workshop On Mini-Micro- And Nano- Dosimetry (Mmnd) And Innovation Technologies In Radiation Oncology (Itro), Anatoly B. Rosenfeld, Marco Zaider, J Yamada, M Zelefsky

Faculty of Engineering and Information Sciences - Papers: Part A

The biannual MMND (former MMD) - IPCT workshops was founded in collaboration between the Centre for Medical Radiation Physics, University of Wollongong and the Memorial Sloan Kettering Cancer Center (MSKCC) in 2001 and has become an important international multidisciplinary forum for the discussion of advanced quality assurance (QA) dosimetry technology for radiation therapy and space science, as well as advanced technologies for clinical cancer treatment.


Parallel Gpu-Based Collision Detection Of Irregular Vessel Wall For Massive Particles, Binbin Yong, Jun Shen, Hongyu Sun, Huaming Chen, Qingguo Zhou Jan 2017

Parallel Gpu-Based Collision Detection Of Irregular Vessel Wall For Massive Particles, Binbin Yong, Jun Shen, Hongyu Sun, Huaming Chen, Qingguo Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we present a novel GPU-based limit space decomposition collision detection algorithm (LSDCD) for performing collision detection between a massive number of particles and irregular objects, which is used in the design of the ADS (Accelerator Driven Sub-Critical) system. Test results indicate that, the collisions between ten million particles and the vessel can be detected on a general personal computer in only 0.5 second per frame. With this algorithm, the collision detection of maximum sixty million particles are calculated in 3.488030 seconds. Experiment results show that our algorithm is promising for fast collision detection.


Fractal Spectral Triples On Kellendonk's C*-Algebra Of A Substitution Tiling, Michael Mampusti, Michael F. Whittaker Jan 2017

Fractal Spectral Triples On Kellendonk's C*-Algebra Of A Substitution Tiling, Michael Mampusti, Michael F. Whittaker

Faculty of Engineering and Information Sciences - Papers: Part A

.We introduce a new class of noncommutative spectral triples on Kellendonk's C*-algebra associated with a nonperiodic substitution tiling. These spectral triples are constructed from fractal trees on tilings, which define a geodesic distance between any two tiles in the tiling. Since fractals typically have infinite Euclidean length, the geodesic distance is defined using Perron-Frobenius theory, and is self-similar with scaling factor given by the Perro-Frobenius eigenvalue. We show that each spectral triple is θ-summable, and respects the hierarchy of the substitution system. To elucidate our results, we construct a fractal tree on the Penrose tiling, and explicitly show ...


Blind Adaptive Multi-User Detection For Under-Ice Acoustic Communications With Mobile Interfering Users, Jingwei Yin, Guang Yang, Defeng (David) Huang, Lu Jin, Qinghua Guo Jan 2017

Blind Adaptive Multi-User Detection For Under-Ice Acoustic Communications With Mobile Interfering Users, Jingwei Yin, Guang Yang, Defeng (David) Huang, Lu Jin, Qinghua Guo

Faculty of Engineering and Information Sciences - Papers: Part A

The Least Mean Squares Blind Adaptive Multi-user Detection algorithm, the Recursive Least Squares Blind Adaptive Multi-user Detection algorithm, and the Kalman Filter Blind Adaptive Multi-user Detection algorithm, for under-ice communication networks with rising and diving interfering users, are investigated in this paper. Under-ice random asynchronous multi-user communication experiments with rising and diving interfering users were carried out (7 users, 15.7 bit/s per user, 1.2 km under-ice acoustic channels in the Bohai Sea). Good experimental results verified the feasibility and effectiveness of the proposed algorithms in mitigating inter-symbol interference and multiple access interference.


Effects Of Fabrication Technique On Tensile Properties Of Fiber Reinforced Polymer, Thong M. Pham, Muhammad N. S Hadi, Jim Youssef Jan 2017

Effects Of Fabrication Technique On Tensile Properties Of Fiber Reinforced Polymer, Thong M. Pham, Muhammad N. S Hadi, Jim Youssef

Faculty of Engineering and Information Sciences - Papers: Part A

This study investigated the effects of fabrication technique on the tensile properties of fiber reinforced polymer (FRP) flat coupon tests. A total of 20 FRP flat coupons were prepared by two different techniques, which were tested in tension until failure. The first technique of preparing the FRP coupons was based on the recommendation of ASTM D7565/D7565M-10, named the “Cutting Technique,” while the second technique, named the “Folding Technique,” was proposed by this study. Experimental results from this study indicated that preparing FRP coupons using the Cutting Technique resulted in a reduction in the tensile properties as compared to coupons ...


Pricing Credit Default Swaps Under A Multi-Scale Stochastic Volatility Model, Wenting Chen, Xin-Jiang He Jan 2017

Pricing Credit Default Swaps Under A Multi-Scale Stochastic Volatility Model, Wenting Chen, Xin-Jiang He

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we consider the pricing of credit default swaps (CDSs) with the reference asset driven by a geometric Brownian motion with a multi-scale stochastic volatility (SV), which is a two-factor volatility process with one factor controlling the fast time scale and the other representing the slow time scale. A key feature of the current methodology is to establish an equivalence relationship between the CDS and the down-and-out binary option through the discussion of "no default" probability, while balancing the two SV processes with the perturbation method. An approximate but closed-form pricing formula for the CDS contract is finally ...


Flexural Behaviour Of Gfrp Reinforced High Strength And Ultra High Strength Concrete Beams, Matthew Goldston, Alex M. Remennikov, M Neaz Sheikh Jan 2017

Flexural Behaviour Of Gfrp Reinforced High Strength And Ultra High Strength Concrete Beams, Matthew Goldston, Alex M. Remennikov, M Neaz Sheikh

Faculty of Engineering and Information Sciences - Papers: Part A

FRP bars are considered alternatives to steel bars for reinforcing concrete structures in harsh environments. FRP bars are non-corrosive, light weight, non-magnetic and have high longitudinal strength and low thermal and electric conductivity. This paper experimentally investigated the flexural behaviour of high strength concrete (HSC) and ultra-high strength concrete (UHSC) beams reinforced with glass fiber reinforced polymer (GFRP) bars that has not been addressed in the literature before. Beams of 2400 mm long, 100 mm wide and 150 mm high were tested under quasi-static loading (three point loading). Influence of reinforcement ratio and compressive strength of concrete (HSC and UHSC ...


Micromechanics-Based Investigation Of Fouled Ballast Using Large-Scale Triaxial Tests And Discrete Element Modeling, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn Jan 2017

Micromechanics-Based Investigation Of Fouled Ballast Using Large-Scale Triaxial Tests And Discrete Element Modeling, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

Railway ballast comprises unbounded discrete grains that are often used to form a load-bearing platform for tracks. Ballast degradation as trains pass over the tracks and infiltration of external fines including slurried (pumped) fine subgrade soils are two of the main reasons for ballast fouling. Fouling causes tracks to settle and also reduces the load-bearing capacity, which is associated with a reduction in internal friction and increased lateral spreading of the ballast layer. This paper presents a study of mobilized friction angle, volumetric behavior, and associated evolutions of contact and fabric anisotropy of fouled ballast subjected to monotonic triaxial loading ...


Factors Governing Mass Transfer During Membrane Electrodialysis Regeneration Of Licl Solution For Liquid Desiccant Dehumidification Systems, Ali Hussein Al-Jubainawi, Zhenjun Ma, Yi Guo, Long D. Nghiem, Paul Cooper, Weihua Li Jan 2017

Factors Governing Mass Transfer During Membrane Electrodialysis Regeneration Of Licl Solution For Liquid Desiccant Dehumidification Systems, Ali Hussein Al-Jubainawi, Zhenjun Ma, Yi Guo, Long D. Nghiem, Paul Cooper, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

This study investigates the mass transfer mechanisms and the performance of membrane electrodialysis (ED) for regenerating lithium chloride (LiCl) solution commonly used in liquid desiccant dehumidification systems. Experiments were conducted using an ED experimental system while numerical simulation was performed using COMSOL Multiphysics. The results showed that the water flux transfer due to osmosis and electro-osmosis during ED regeneration of LiCl liquid desiccant was significant and could not be ignored. The water flux due to osmosis and electro-osmosis is directly associated with the osmotic gradient and the applied current between the cathode and anode, respectively. The average flux of water ...


Performance Evaluation Of High Strength Concrete And Steel Fibre High Strength Concrete Columns Reinforced With Gfrp Bars And Helices, Hayder Alaa Hasan, M Neaz Sheikh, Muhammad N. S Hadi Jan 2017

Performance Evaluation Of High Strength Concrete And Steel Fibre High Strength Concrete Columns Reinforced With Gfrp Bars And Helices, Hayder Alaa Hasan, M Neaz Sheikh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

This study presents the results of an experimental investigation on high strength concrete (HSC) and steel fibre high strength concrete (SFHSC) circular column specimens reinforced longitudinally and transversely with Glass Fibre-Reinforced Polymer (GFRP) bars and helices, respectively. The Influence of the type of the reinforcement (steel and GFRP), the pitch of the transverse reinforcement, the addition of the steel fibres and the loading condition (concentric, eccentric and four-point loading) on the performance of the specimens was investigated. The study showed that the GFRP bar reinforced HSC (GFRP-HSC) specimen is as efficient as the steel bar reinforced HSC (steel-HSC) specimen in ...


Improvement Of Microstructure And Properties In Twin-Roll Casting 7075 Sheet By Lower Casting Speed And Compound Field, G Chen, Jintao Li, Z K. Yin, G M. Xu Jan 2017

Improvement Of Microstructure And Properties In Twin-Roll Casting 7075 Sheet By Lower Casting Speed And Compound Field, G Chen, Jintao Li, Z K. Yin, G M. Xu

Faculty of Engineering and Information Sciences - Papers: Part A

Well-developed dendrites and severe macro and micro segregations in 7075 sheet produced by horizontal twin-roll casting (TRC) deteriorates the hot-workability and properties of the sheet, which makes an obstacle for the successful use of this technology. In this paper, lower casting speed and a pulsed electric-magnetostatic compound field are used to refine microstructure and abate segregation in TRC 7075 sheet. The dendrite arm space decreases from 20 ¿m to 8¿13 ¿m and the micro-segregation degree of Mg, Zn and Cu decreases when casting speed decreases from 1.5 m/min to 0.75 m/min. The center macro-segregation belt ...