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Full-Text Articles in Social and Behavioral Sciences

Event-Triggered H∞ Control For Active Seat Suspension Systems Based On Relaxed Conditions For Stability, Wenxing Li, Haiping Du, Donghong Ning, Weihua Li, Shuaishuai Sun, Jumei Wei Jan 2021

Event-Triggered H∞ Control For Active Seat Suspension Systems Based On Relaxed Conditions For Stability, Wenxing Li, Haiping Du, Donghong Ning, Weihua Li, Shuaishuai Sun, Jumei Wei

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Elsevier Ltd An event-triggered H∞ controller is designed for an active seat suspension in this paper, where the continuous event-trigger scheme is applied to transfer the dynamic system states to the controller only at event-triggered time instants. Delay-dependent stability criteria in the form of linear matrix inequality (LMI) are presented to guarantee the asymptotic stability of the seat suspension system. One Lyapunov function is chosen where some matrices are introduced with relaxed conditions. Two tight inequalities are applied to prove the positive definiteness of the Lyapunov function and stability of the system, which reduces the conservatism of the …


Seismic Performance Of Concrete-Filled Shs Column-To-Beam Connections With Slip-Critical Blind Bolts, Weifeng Jiao, Wei Wang, Yiyi Chen, Lip H. Teh Jan 2020

Seismic Performance Of Concrete-Filled Shs Column-To-Beam Connections With Slip-Critical Blind Bolts, Weifeng Jiao, Wei Wang, Yiyi Chen, Lip H. Teh

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Elsevier Ltd This paper investigates the use of slip-critical blind bolts to connect I-beams to concrete-filled steel square hollow section (SHS) columns. The strength and stiffness of the resulting joints are determined experimentally for the purpose of classifying them according to the Eurocode. Their suitability for use in special moment frames is also assessed through cyclic bending tests. Three types of beam sections are tested, being a compact welded section, a reduced beam (flange) section, and a reduced beam section with concrete slab at the top. All tested joints are full strength according to the Eurocode, allowing the …


Recent Advancements In G-C3n4-Based Photocatalysts For Photocatalytic Co2reduction: A Mini Review, Runlu Liu, Zhixin Chen, Yao Yao, Yao Li, Waqas A. Cheema, Dawei Wang, Shenmin Zhu Jan 2020

Recent Advancements In G-C3n4-Based Photocatalysts For Photocatalytic Co2reduction: A Mini Review, Runlu Liu, Zhixin Chen, Yao Yao, Yao Li, Waqas A. Cheema, Dawei Wang, Shenmin Zhu

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 The Royal Society of Chemistry. Carbon dioxide (CO2) is a very important micro-molecular resource. Using CO2 captured from the atmosphere for high-output synthesis of chemicals as raw materials has great significance and potential for various industrial applications. Since the industrial revolution in the 18th century, manmade CO2 emission has increased by 45%, which negatively impacts the planetary climate by the so-called greenhouse effect. Therefore, high-efficiency photocatalysis and photocatalysts for CO2 conversion have become the most important challenges and milestones throughout the world. In consideration of this, various catalysts have been explored. Among these, graphitic carbon nitride (g-C3N4) as …


Using Cost-Sensitive Learning And Feature Selection Algorithms To Improve The Performance Of Imbalanced Classification, Fang Feng, Kuan-Ching Li, Jun Shen, Qingguo Zhou, Xuhui Yang Jan 2020

Using Cost-Sensitive Learning And Feature Selection Algorithms To Improve The Performance Of Imbalanced Classification, Fang Feng, Kuan-Ching Li, Jun Shen, Qingguo Zhou, Xuhui Yang

Faculty of Engineering and Information Sciences - Papers: Part A

Imbalanced data problem is widely present in network intrusion detection, spam filtering, biomedical engineering, finance, science, being a challenge in many real-life data-intensive applications. Classifier bias occurs when traditional classification algorithms are used to deal with imbalanced data. As already known, the General Vector Machine (GVM) algorithm has good generalization ability, though it does not work well for the imbalanced classification. Additionally, the state-of-the-art Binary Ant Lion Optimizer (BALO) algorithm has high exploitability and fast convergence rate. Based on these facts, we have proposed in this paper a Cost-sensitive Feature selection General Vector Machine (CFGVM) algorithm based on GVM and …


Automatic Ventricular Nuclear Magnetic Resonance Image Processing With Deep Learning, Binbin Yong, Chen Wang, Jun Shen, Fucun Li, Hang Yin Jan 2020

Automatic Ventricular Nuclear Magnetic Resonance Image Processing With Deep Learning, Binbin Yong, Chen Wang, Jun Shen, Fucun Li, Hang Yin

Faculty of Engineering and Information Sciences - Papers: Part A

Cardiovascular diseases (CVD) seriously threaten the health of human beings, and they have caused widespread concern in recent years. At present, the diagnosis of CVD is mainly conducted by computed tomography (CT), echocardiography and nuclear magnetic resonance (NMR) technologies. NMR imaging technology is widely used in medical applications owing to its characteristics of high resolution and very low radiation. However, manual NMR image segmentation is time-consuming and error-prone, which has led to the research on automatic NMR image segmentation technologies. Researchers tend to explore the ventricular NRM image segmentation to improve the accuracy of CVD diagnosis. In this study, based …


An In Situ Synchrotron Study Of The Localized B2↔B19' Phase Transformation In An Ni-Ti Alloy Subjected To Uniaxial Cyclic Loading-Unloading With Incremental Strains, Xiaohui Bian, Ahmed A. Saleh, Peter Lynch, Christopher Davies, Azdiar Adil Gazder, Elena V. Pereloma Jan 2020

An In Situ Synchrotron Study Of The Localized B2↔B19' Phase Transformation In An Ni-Ti Alloy Subjected To Uniaxial Cyclic Loading-Unloading With Incremental Strains, Xiaohui Bian, Ahmed A. Saleh, Peter Lynch, Christopher Davies, Azdiar Adil Gazder, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020. High-resolution in situ synchrotron X-ray diffraction was applied to study a cold-drawn and solution-treated 56Ni-44Tiwt% alloy subjected to uniaxial cyclic loading-unloading with incremental strains. The micro-mechanical behaviour associated with the partial and repeated B2↔B19' phase transformation at the centre of the sample gauge length was studied with respect to the macroscopic stress-strain response. The lattice strains of the (110)B2 and different B19' grain families are affected by (i) the transformation strain, the load-bearing capacity of both phases and the strain continuity maintained at/near the B2-B19' interfaces at the centre of the gauge length, and (ii) the extent of …


Microstructural Evolution Of Hybrid Aluminum Matrix Composites Reinforced With Sic Nanoparticles And Graphene/Graphite Prepared By Powder Metallurgy, Jiangshan Zhang, Qing Liu, Shufeng Yang, Zhixin Chen, Qiang Liu, Zhengyi Jiang Jan 2020

Microstructural Evolution Of Hybrid Aluminum Matrix Composites Reinforced With Sic Nanoparticles And Graphene/Graphite Prepared By Powder Metallurgy, Jiangshan Zhang, Qing Liu, Shufeng Yang, Zhixin Chen, Qiang Liu, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Chinese Materials Research Society The dispersion of ceramic nanoparticles is of significance to the microstructure and properties of particulate reinforced metal matrix composites. In this study, two hybrid enhancers, SiC-graphite and SiC-graphene nanosheets (GNSs), were incorporated into aluminum matrix composites using powder metallurgy. The dispersion of the reinforcements and microstructural evolution of the composites were characterized by using Scanning Electron Microscopy, X-Ray Diffraction, Transmission Electron Microscopy, and Raman spectroscopy. The results show that thin GNSs accelerated the deformation of the aluminum particles, and defects were introduced into the carbonaceous phases during the ball milling process. Al4C3 needles generated …


Hybrid Translation And Language Model For Micro Learning Material Recommendation, Jiayin Lin Jan 2020

Hybrid Translation And Language Model For Micro Learning Material Recommendation, Jiayin Lin

Faculty of Engineering and Information Sciences - Papers: Part A

As an emerging pedagogy, micro learning aims to make use of people’s fragmented spare time and provide personalized online learning service, for example, by pushing fragmented knowledge to specific learners. In the context of big data, the recommender system is the key factor for realizing the online personalization service, which significantly determines what information will be fmally accessed by the target learners. In the education discipline, due to the pedagogical requirements and the domain characteristics, ranking recommended learning materials is essential for maintaining the outcome of the massive learning scenario. However, many widely used recommendation strategies in other domains showed …


Autonomous Control Strategy For Microgrid Operating Modes Smooth Transition, Yaran Li, Long Fu, Ke Meng, Zhao Dong, Kashem M. Muttaqi, Wenli Du Jan 2020

Autonomous Control Strategy For Microgrid Operating Modes Smooth Transition, Yaran Li, Long Fu, Ke Meng, Zhao Dong, Kashem M. Muttaqi, Wenli Du

Faculty of Engineering and Information Sciences - Papers: Part A

© 2013 IEEE. Microgrid transition between standalone and grid-connected modes is a promising alternative to provide the grid with increasing flexibility and availability. However, transition smoothness relies heavily on control topologies and corresponding parameters, which thus remains challengeable. Existing microgrid transition strategies have two major deficiencies: 1) Inverter control mode alters subjected to microgrid operating mode, for instance, the inverter in current control will switch to voltage control when microgrid disconnects to the utility grid; 2) Controller parameters are selected based on practice and experience, where a systematic and efficient approach does not exist. Motivated by these limitations, in this …


Thermionic Emission In Nodal-Ring Semimetals, Suguo Chen, Sunchao Huang, Wenye Duan, Wei Shi, C Zhang Jan 2020

Thermionic Emission In Nodal-Ring Semimetals, Suguo Chen, Sunchao Huang, Wenye Duan, Wei Shi, C Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Author(s). We theoretically investigate the thermionic emission from nodal-ring semimetals. The thermionic emission is found to be anisotropic in the x- and y-directions. The anisotropic emission can be enhanced by increasing the radius of nodal-ring b. The main feature of nodal-ring semimetals not only results in anisotropic thermionic emission but also affects the value of thermionic emission current density (TECD). The TECD of the lower branch of the energy-momentum dispersion increases with b, while the TECD of the upper branch decreases with b. Unlike in conventional materials, the TECD in nodal-ring semimetals depends on Fermi energy that is …


Reachable Set Estimation For Neutral Markovian Jump Systems With Mode-Dependent Time-Varying Delays, Xiangli Jiang, Guihua Xia, Zhiguang Feng, Zhengyi Jiang Jan 2020

Reachable Set Estimation For Neutral Markovian Jump Systems With Mode-Dependent Time-Varying Delays, Xiangli Jiang, Guihua Xia, Zhiguang Feng, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 John Wiley & Sons Ltd This study, under zero initial condition, aims to characterize the reachable set bound for a class of neutral Markovian jump systems (NMJSs) with interval time-varying delays and bounded disturbances. To begin with, the time-delays are considered to be mode-dependent while delay mode and system mode are different. By utilizing free-weighting matrix method and reciprocally convex combination technique, an ellipsoid-like bound is characterized for the concerned NMJS with completely known transition probabilities. Based on the provided analytical framework, the case of same delay mode and system mode is also handled. Then, benefitting from a …


A 3d Printed Modular Soft Gripper For Conformal Grasping, Charbel Tawk, Rahim Mutlu, Gursel Alici Jan 2020

A 3d Printed Modular Soft Gripper For Conformal Grasping, Charbel Tawk, Rahim Mutlu, Gursel Alici

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 IEEE. In this work, a 3D printed modular soft gripper with highly conformal soft fingers was developed. A soft auxetic structure with compliant ribs is 3D printed simultaneously with each soft pneumatic finger for conformal grasping. The fingers of the soft gripper were printed monolithically, without requiring support material and postprocessing, using a low-cost and open-source fused deposition modeling (FDM) 3D printer that employs a commercially available thermoplastic polyurethane (TPU). The soft fingers of the gripper were optimized using finite element modeling (FEM). The FE simulations accurately predicted the performance of the fingers in terms of deformation and …


Pressure-Drop Modelling In The Softening And Melting Test For Ferrous Burden, Subhasish Mitra, Xinliang Liu, Tom Honeyands, Geoffrey Evans, Damien O'Dea, Paul Zulli Jan 2020

Pressure-Drop Modelling In The Softening And Melting Test For Ferrous Burden, Subhasish Mitra, Xinliang Liu, Tom Honeyands, Geoffrey Evans, Damien O'Dea, Paul Zulli

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 ISIJ The softening and melting (SM) under load test is routinely conducted to assess the quality of ferrous burden materials and to predict their possible performance in blast furnace. Due to complex phase interactions coupled with chemical reactions at an elevated temperature range (~973 to 1 873 K), the flow dynamics in the test system are quite complex. This study systematically investigates the contraction behaviour and associated pressure drop in a SM test bed for sinter, lump (NBLL, Newman Blend Lump) and a mixture of these two types of ore (21 wt% NBLL + 79 wt% sinter). To …


Model-Free Adaptive Iterative Learning Control Of Melt Pool Width In Wire Arc Additive Manufacturing, Chunyang Xia, Zengxi Stephen Pan, Shiyu Zhang, Hui Jun Li, Yanling Xu, Shanben Chen Jan 2020

Model-Free Adaptive Iterative Learning Control Of Melt Pool Width In Wire Arc Additive Manufacturing, Chunyang Xia, Zengxi Stephen Pan, Shiyu Zhang, Hui Jun Li, Yanling Xu, Shanben Chen

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020, Springer-Verlag London Ltd., part of Springer Nature. Wire arc additive manufacturing (WAAM) is a Direct Energy Deposition (DED) technology, which utilize electrical arc as heat source to deposit metal material bead by bead to make up the final component. However, issues like the lack of assurance in accuracy, repeatability and stability hinder the further application in industry. Therefore, a Model Free Adaptive Iterative Learning Control (MFAILC) algorithm was developed to be applied in WAAM process in this study. The dynamic process of WAAM is modelled by adaptive neuro fuzzy inference system (ANFIS). Based on this ANFIS model, simulations …


Effect Of Quantum Reflection Over The Barrier On Thermionic Refrigeration, Zeyu Zhang, Zelong Peng, Zhongshui Ma, C Zhang Jan 2020

Effect Of Quantum Reflection Over The Barrier On Thermionic Refrigeration, Zeyu Zhang, Zelong Peng, Zhongshui Ma, C Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Author(s). We study the effect of quantum reflection over the barrier (ROB) in a thermionic cooling device. We find that the performance of refrigerators can be enhanced by the ROB effect if the bias voltage and the lattice thermal resistance of the semiconductor in the barrier region are both sufficiently high. Furthermore, the figure of merit Z T can be higher due to the ROB effect if the workfunction of the cathode is low and the lattice thermal resistance is high. The overall optimum Z T calculated with and without the ROB effect are 6.5 and 7.1, respectively. …


High Sensitivity Face Shear Magneto-Electric Composite Array For Weak Magnetic Field Sensing, Yun Lu, Zhenxiang Cheng, Jianguo Chen, Weihua Li, Shujun Zhang Jan 2020

High Sensitivity Face Shear Magneto-Electric Composite Array For Weak Magnetic Field Sensing, Yun Lu, Zhenxiang Cheng, Jianguo Chen, Weihua Li, Shujun Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Author(s). A magnetic field sensor is designed and fabricated using a piezoelectric face shear mode Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT)/Metglas magneto-electric (ME) composite. An outstanding ME coupling coefficient up to 1600 V/(cm Oe) was experimentally achieved, being ∼50% higher than the value from the extensional PMN-PT/Metglas ME composite with the same volume. The detection limit was found to be 2 × 10-6 Oe for the DC magnetic field, while it was 2 × 10-8 Oe for the AC magnetic field. The sensitivity of the face shear mode PMN-PT/Metglas ME composite is about one order of magnitude higher than that of a …


Beyond Covariance: Sice And Kernel Based Visual Feature Representation, Jianjia Zhang, Lei Wang, Luping Zhou, Wanqing Li Jan 2020

Beyond Covariance: Sice And Kernel Based Visual Feature Representation, Jianjia Zhang, Lei Wang, Luping Zhou, Wanqing Li

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020, Springer Science+Business Media, LLC, part of Springer Nature. The past several years have witnessed increasing research interest on covariance-based feature representation. Originally proposed as a region descriptor, it has now been used as a general representation in various recognition tasks, demonstrating promising performance. However, covariance matrix has some inherent shortcomings such as singularity in the case of small sample, limited capability in modeling complicated feature relationship, and a single, fixed form of representation. To achieve better recognition performance, this paper argues that more capable and flexible symmetric positive definite (SPD)-matrix-based representation shall be explored, and this is attempted …


Comparison Of A Laboratory-Scale Coke And A Pilot-Scale Coke From Matched Coal, Hannah Lomas, Richard Roest, Adam Wells, Tizshauna Thorley, Hui Wu, Zhengyi Jiang, Richard Sakurovs, Robert Fetscher, Xing Xing, Merrick Mahoney Jan 2020

Comparison Of A Laboratory-Scale Coke And A Pilot-Scale Coke From Matched Coal, Hannah Lomas, Richard Roest, Adam Wells, Tizshauna Thorley, Hui Wu, Zhengyi Jiang, Richard Sakurovs, Robert Fetscher, Xing Xing, Merrick Mahoney

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Institute of Materials, Minerals and Mining. A coke produced using a custom-built sole-heated oven and a coke prepared in a pilot-scale oven from a matched coal, were compared using a range of analytical techniques. The aim of this comparison was to assess to what extent the small-scale sole-heated oven can successfully replicate the production of pilot-scale oven cokes, and thus be used to rapidly prepare and screen a wide range of cokes for particular characteristics, e.g. abrasion resistance. The techniques applied included conventional methods and novel methods developed by our research team. These included microstructural and microtextural analyses …


Towards Mr-Guided Electron Therapy: Measurement And Simulation Of Clinical Electron Beams In Magnetic Fields, R Kueng, Bradley M. Oborn, N Roberts, Trent Causer, M Stampanoni, P Manser, P Keall, M Fix Jan 2020

Towards Mr-Guided Electron Therapy: Measurement And Simulation Of Clinical Electron Beams In Magnetic Fields, R Kueng, Bradley M. Oborn, N Roberts, Trent Causer, M Stampanoni, P Manser, P Keall, M Fix

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Associazione Italiana di Fisica Medica Purpose: In the current era of MRI-linac radiotherapy, dose optimization with arbitrary dose distributions is a reality. For the first time, we present new and targeted experiments and modeling to aid in evaluating the potential dose improvements offered with an electron beam mode during MRI-linac radiotherapy. Methods: Small collimated (1 cm diameter and 1.5 × 1.5 cm2 square) electron beams (6, 12 and 20 MeV) from a clinical linear accelerator (Varian Clinac 2100C) are incident perpendicular and parallel to the strong and localized magnetic fields (0–0.7 T) generated by a permanent magnet device. …


An International Survey On The Clinical Use Of Rigid And Deformable Image Registration In Radiotherapy, Johnson Yuen, Jeffrey Barber, Anna C. Ralston, Alison Gray, Amy L. Walker, Nicholas G. Hardcastle, Laurel Schmidt, Kristie Harrison, Joel Poder, Jonathan Sykes, Michael G. Jameson Jan 2020

An International Survey On The Clinical Use Of Rigid And Deformable Image Registration In Radiotherapy, Johnson Yuen, Jeffrey Barber, Anna C. Ralston, Alison Gray, Amy L. Walker, Nicholas G. Hardcastle, Laurel Schmidt, Kristie Harrison, Joel Poder, Jonathan Sykes, Michael G. Jameson

Faculty of Engineering and Information Sciences - Papers: Part A

Objectives: Rigid image registration (RIR) and deformable image registration (DIR) are widely used in radiotherapy. This project aims to capture current international approaches to image registration. Methods: A survey was designed to identify variations in use, resources, implementation, and decision-making criteria for clinical image registration. This was distributed to radiotherapy centers internationally in 2018. Results: There were 57 responses internationally, from the Americas (46%), Australia/New Zealand (32%), Europe (12%), and Asia (10%). Rigid image registration and DIR were used clinically for computed tomography (CT)-CT registration (96% and 51%, respectively), followed by CT-PET (81% and 47%), CT-CBCT (84% and 19%), CT-MR …


Information Security Governance Challenges And Critical Success Factors: Systematic Review, Sultan Safar A Al Ghamdi, Khin Than Win, Elena Vlahu-Gjorgievska Jan 2020

Information Security Governance Challenges And Critical Success Factors: Systematic Review, Sultan Safar A Al Ghamdi, Khin Than Win, Elena Vlahu-Gjorgievska

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Elsevier Ltd Information security is a critical aspect and plays a significant role in protecting an organization's business. Organizations are required to safeguard their information and assets to sustain their value and reputation. The systematic literature review presented in this paper aims to introduce information security governance as a comprehensive solution for alignment between information security policies and the organization's objectives. The review identified the need for developing a holistic framework for the information security governance that (1) connects the organization's objectives and its protection, (2) addresses each aspect of strategy, control, and regulation, (3) ensures compliance of …


Ecological, Economical And Technological Perspectives Based Sustainability Assessment In Hybrid-Cooling Assisted Machining Of Ti-6al-4 V Alloy, Munish Gupta, Qinghua Song, Zhanqiang Liu, Murat Sarikaya, Muhammad Jamil, Mozammel Mia, Vinod Kushvaha, Anil Singla, Zhixiong Li Jan 2020

Ecological, Economical And Technological Perspectives Based Sustainability Assessment In Hybrid-Cooling Assisted Machining Of Ti-6al-4 V Alloy, Munish Gupta, Qinghua Song, Zhanqiang Liu, Murat Sarikaya, Muhammad Jamil, Mozammel Mia, Vinod Kushvaha, Anil Singla, Zhixiong Li

Faculty of Engineering and Information Sciences - Papers: Part A

© 2020 Elsevier B.V. Ti-6Al-4 V alloy is a well-acknowledged standard material for the application of modern aerospace, surgical equipment, and prosthetic body parts owing to its stable thermo-physical properties at elevated temperature. However, this structure stability imparts its low thermal conductivity that leads to buildup of heat at tool-workpiece interface during machining which subsequently has a damaging effect on the tool cutting edge. Several biodegradable cutting fluids have already been attempted controlling the heat generation, environmental footprints to improve the overall machinability. In this endeavor, the effectiveness of dry, liquid nitrogen (LN2) and hybrid cryogenic and minimum quantity lubrication …


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 …


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.


Vibration-Induced Aerodynamic Loads On Large Horizontal Axis Wind Turbine Blades, Xiong Liu, Cheng Lu, Shi Liang, Ajit R. Godbole, Yan Chen Jan 2017

Vibration-Induced Aerodynamic Loads On Large Horizontal Axis Wind Turbine Blades, Xiong Liu, Cheng Lu, Shi Liang, Ajit R. Godbole, Yan Chen

Faculty of Engineering and Information Sciences - Papers: Part A

The blades of a large Horizontal Axis Wind Turbine (HAWT) are subjected to significant vibrations during operation. The vibrations affect the dynamic flow field around the blade and consequently alter the aerodynamic forces on the blade. In order to better understand the influence of blade vibrations on the aerodynamic loads, the dynamic stall characteristics of an S809 airfoil undergoing translational motion as well as pitching motion were investigated using Computational Fluid Dynamics (CFD) techniques. Simulation results indicated that both the out-of-plane and in-plane translational motions of the airfoil affect the unsteady aerodynamic forces significantly. In order to investigate the effects …


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 …


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 …


Thin-Film Composite Forward Osmosis Membranes Functionalized With Graphene Oxide-Silver Nanocomposites For Biofouling Control, Andreia Faria, Caihong Liu, Ming Xie, Francois Perreault, Long D. Nghiem, Jun Ma, Menachem Elimelech Jan 2017

Thin-Film Composite Forward Osmosis Membranes Functionalized With Graphene Oxide-Silver Nanocomposites For Biofouling Control, Andreia Faria, Caihong Liu, Ming Xie, Francois Perreault, Long D. Nghiem, Jun Ma, Menachem Elimelech

Faculty of Engineering and Information Sciences - Papers: Part A

Innovative approaches to prevent bacterial attachment and biofilm growth on membranes are critically needed to avoid decreasing membrane performance due to biofouling. In this study, we propose the fabrication of anti-biofouling thin-film composite membranes functionalized with graphene oxide-silver nanocomposites. In our membrane modification strategy, carboxyl groups on the graphene oxide-silver nanosheets are covalently bonded to carboxyl groups on the surface of thin-film composite membranes via a crosslinking reaction. Further characterization, such as scanning electron microscopy and Raman spectroscopy, revealed the immobilization of graphene oxide-silver nanocomposites on the membrane surface. Graphene oxide-silver modified membranes exhibited an 80% inactivation rate against attached …


Liquid Desiccant Lithium Chloride Regeneration By Membrane Distillation For Air Conditioning, Hung Duong, Faisal I. Hai, Ali Aljubainawi, Zhenjun Ma, Tao He, Long D. Nghiem Jan 2017

Liquid Desiccant Lithium Chloride Regeneration By Membrane Distillation For Air Conditioning, Hung Duong, Faisal I. Hai, Ali Aljubainawi, Zhenjun Ma, Tao He, Long D. Nghiem

Faculty of Engineering and Information Sciences - Papers: Part A

Liquid desiccant air conditioning (LDAC) has emerged as an attractive technology for improving indoor air quality and thermal comfort. Regeneration of liquid desiccants is critical to sustain the process efficiency of LDAC. This study explores membrane distillation (MD) for regeneration of lithium chloride (LiCl) desiccant solution commonly used in LDAC. The results demonstrate the viability of MD for LiCl regeneration. The MD process at the feed temperature of 65 °C could increase the LiCl concentration up to 29 wt.% without any observable LiCl loss. Given the high concentration of the LiCl solution feed, unlike traditional desalination applications, the impact of …


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 …