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Corrosion Resistance Of Electrified Railway Tunnels Made Of Steel Fibre Reinforced Concrete, Kangkang Tang, Stephen Wilkinson Jan 2020

Corrosion Resistance Of Electrified Railway Tunnels Made Of Steel Fibre Reinforced Concrete, Kangkang Tang, Stephen Wilkinson

University of Wollongong in Dubai - Papers

Steel fibre reinforced concrete (SFRC) has been widely used in the construction of buildings, roads and bridges where high compressive and/or tensile strength is preferred. From a structural perspective, SFRC is an ideal substitute for conventional steel reinforcement in railway tunnel construction. However, it is still not clear whether discontinuous steel fibres can pick up and transfer stray current, especially stray alternating current (AC), and lead to similar corrosive attacks as occur in conventional steel reinforcement. The development of suitable approaches for the assessment of the corrosion susceptibility of SFRC under stray AC conditions is a primary aim of this …

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Sustainability Report Practices In Indonesia: Context, Policy, And Readability, Iman Harymawan, Fajar Putra, Tanaya Agni, Khairul Kamarudin Jan 2020

Sustainability Report Practices In Indonesia: Context, Policy, And Readability, Iman Harymawan, Fajar Putra, Tanaya Agni, Khairul Kamarudin

University of Wollongong in Dubai - Papers

Considering sustainability disclosure become one important issue, while still there no universal agreement for the guidance, this study aims to examine Indonesia's Sustainability Disclosure trend using GRI as quantity dimension, KLD for the quality, and readability and PROPER to measure how well they communicate. This study uses a sample of 224 firm-year observation from 2013 to 2017 based on GRI database. Descriptive analytic employed to figure disclosure trend in general, year to year, and industry base, and Pearson to explain correlation between measurements. There are three important issue discovered in this research. First, Indonesia's sustainability disclosure is generally low but …

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Flexible Co-Planar Waveguide (Cpw)-Fed Y-Shaped Patch Uwb Antenna For Off-Body Communication, S Kassim, Hasliza Rahim, Ping Soh, Mohd Fareq Abdul Malek, Muzammil Jusoh, Mohd Jamaluddin, N Sabli, M Yassin, T Sabapathy, F Wee, M Osman, N L. Ismail Jan 2020

Flexible Co-Planar Waveguide (Cpw)-Fed Y-Shaped Patch Uwb Antenna For Off-Body Communication, S Kassim, Hasliza Rahim, Ping Soh, Mohd Fareq Abdul Malek, Muzammil Jusoh, Mohd Jamaluddin, N Sabli, M Yassin, T Sabapathy, F Wee, M Osman, N L. Ismail

University of Wollongong in Dubai - Papers

2020 IOP Publishing Ltd. All rights reserved. This paper intends to design an Ultra-Wideband (UWB) antenna for future Internet of Things (IoT) applications for off-body Wireless Body Area Networks (WBAN) communication. An antenna based on the Y-shaped patch fed using co-planar waveguide (CPW) line, with a full ground plane is designed. It is implemented on two different substrates, namely a 5mm thick Rogers RO4350B and a 5-mm-thick felt textile. Parametric analysis of antenna is performed by changing its critical dimensions and monitoring parameters such as gain, bandwidth, efficiency, radiation pattern when using both substrates. Besides that, the bending effects towards …

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Pursuit Learning-Based Joint Pilot Allocation And Multi-Base Station Association In A Distributed Massive Mimo Network, Naufan Raharya, Wibowo Hardjawana, Obada Al Khatib, Branka Vucetic Jan 2020

Pursuit Learning-Based Joint Pilot Allocation And Multi-Base Station Association In A Distributed Massive Mimo Network, Naufan Raharya, Wibowo Hardjawana, Obada Al Khatib, Branka Vucetic

University of Wollongong in Dubai - Papers

2013 IEEE. Pilot contamination (PC) interference causes inaccurate user equipment (UE) channel estimations and significant signal-to-interference ratio (SINR) degradations. Pilot allocation and multi-base-station (BS) association have been used to combat the PC effect and to maximize the network spectral efficiency. However, current approaches solve the pilot allocation and multi-BS association separately. This leads to a sub-optimal solution. In this paper, we propose a parallel pursuit-learning-based joint pilot allocation and multi-BS association. We first formulate the pilot allocation and multi-BS association problem as a joint optimization function. To solve the optimization function, we use a parallel optimization solver, based on a …

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An Artificial Intelligence Based Crowdsensing Solution For On-Demand Accident Scene Monitoring, May El Barachi, Faouzi Kamoun, Jannatul Ferdaos, Mouna Makni, Imed Amri Jan 2020

An Artificial Intelligence Based Crowdsensing Solution For On-Demand Accident Scene Monitoring, May El Barachi, Faouzi Kamoun, Jannatul Ferdaos, Mouna Makni, Imed Amri

University of Wollongong in Dubai - Papers

Road traffic crashes have a devastating impact on societies by claiming more than 1.35 million lives each year and causing up to 50 million injuries. Improving the efficiency of emergency management systems constitutes a key measure to reduce road traffic deaths and injuries. In this work, we propose a comprehensive crowdsensing-based solution for the real-time collection and the analysis of accident scene intelligence as a means to improve the efficiency of the emergency response process and help reduce road fatalities. The solution leverages sensory, mobile, web technologies for the real-time monitoring of accident scenes, employs Artificial Intelligence for the automatic …

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Expanding Customer Engagement: The Role Of Negative Engagement, Dual Valences And Contexts, Kay Naumann, Jana Bowden, Mark Gabbott Jan 2020

Expanding Customer Engagement: The Role Of Negative Engagement, Dual Valences And Contexts, Kay Naumann, Jana Bowden, Mark Gabbott

University of Wollongong in Dubai - Papers

2020, Kay Naumann, Jana Bowden and Mark Gabbott. Purpose: The purpose of this study is to operationalise and measure the effects of negative customer engagement (CE) in conjunction with positive CE. Both valences are explored through affective, cognitive and behaviour dimensions, and, in relation to the antecedent of involvement and outcome of word-of-mouth (WOM). It also explores the moderating influence of service context by examining engagement within a social service versus a social networking site (SNS). Engagement with the dual focal objects of a service brand and a service community are also examined. Design/methodology/approach: Structural equation modelling is used to …

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A Novel Pre-Class Learning Content Approach For The Implementation Of Flipped Classrooms, Soly Mathew Biju, Ayodeji Salau, Joy Eneh, Vincent Sochima, Izuchukwu Ozue Jan 2020

A Novel Pre-Class Learning Content Approach For The Implementation Of Flipped Classrooms, Soly Mathew Biju, Ayodeji Salau, Joy Eneh, Vincent Sochima, Izuchukwu Ozue

University of Wollongong in Dubai - Papers

The nascent recognition of computing in curriculum across countries is also accompanied by several pedagogic inefficiencies especially concerning insufficient time available for teacher-student interaction. In this paper, a flipped classroom concept was identified as an effective approach to teaching students at various levels in the academia including Higher Education. Preparing the pre-class content and considering the format used to deliver it has not gained much consideration. There are several ways in which this content could be provided to students to prepare them before an in-class activity where a flipped-classroom approach can be implemented. The present study analyzed the success of …

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Investigations Of The Effects Of Particle Morphology On Granular Material Behaviors Using A Multi-Sphere Approach, Shiva Kodicherla, Guobin Gong, Lei Fan, Stephen Wilkinson, Charles Moy Jan 2020

Investigations Of The Effects Of Particle Morphology On Granular Material Behaviors Using A Multi-Sphere Approach, Shiva Kodicherla, Guobin Gong, Lei Fan, Stephen Wilkinson, Charles Moy

University of Wollongong in Dubai - Papers

This article studies the influences of particle morphology on the behaviors of granular materials at both macroscopic and microscopic levels based on the discrete element method (DEM). A set of numerical tests under drained triaxial compression was performed by controlling two morphological descriptors, i.e. ratio of the smallest to the largest pebble diameter, ξ, and the maximum pebble-pebble intersection angle, β. These descriptors are vital in generating particle geometry and surface textures. It was found that the stress responses of all assemblies exhibited similar behavior and showed post-peak strain-softening. The normalized stress ratio and volumetric strains flatten off and tended …

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Extreme Return-Volume Relationship In Cryptocurrencies: Tail Dependence Analysis, Muhammad Naeem, Kashif Saleem, Sheraz Ahmed, Naeem Muhammad, Faisal Mustafa Jan 2020

Extreme Return-Volume Relationship In Cryptocurrencies: Tail Dependence Analysis, Muhammad Naeem, Kashif Saleem, Sheraz Ahmed, Naeem Muhammad, Faisal Mustafa

University of Wollongong in Dubai - Papers

2020 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license. We explore extreme return-volumes dependence among different cryptocurrencies such as Bitcoin, Ethereum, Ripple, and Litecoin by using the Copula approach. We use Student-t, Frank, Clayton, Survival Clayton, Gumbel, and SJC copulas. We filter out margins by using the EGARCH model for return series and GARCH model for volume series. Evidence of significant symmetric dependence between return-volume is not found due to insignificance of student-t and Frank copula parameters. In a return-volume relationship, coefficients of lower tail dependence are significant for Bitcoin, Ripple, and …

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A Hybrid Modified Method Of The Sine Cosine Algorithm Using Latin Hypercube Sampling With The Cuckoo Search Algorithm For Optimization Problems, Siti Rosli, Hasliza Rahim, Khairul Najmy Abdul Rani, Ruzelita Ngadiran, R Ahmad, Nor Yahaya, Mohd Fareq Abdul Malek, Muzammil Jusoh, Mohd Yasin, Thennarasan Sabapathy, Allan Andrew Jan 2020

A Hybrid Modified Method Of The Sine Cosine Algorithm Using Latin Hypercube Sampling With The Cuckoo Search Algorithm For Optimization Problems, Siti Rosli, Hasliza Rahim, Khairul Najmy Abdul Rani, Ruzelita Ngadiran, R Ahmad, Nor Yahaya, Mohd Fareq Abdul Malek, Muzammil Jusoh, Mohd Yasin, Thennarasan Sabapathy, Allan Andrew

University of Wollongong in Dubai - Papers

The metaheuristic algorithm is a popular research area for solving various optimization problems. In this study, we proposed two approaches based on the Sine Cosine Algorithm (SCA), namely, modification and hybridization. First, we attempted to solve the constraints of the original SCA by developing a modified SCA (MSCA) version with an improved identification capability of a random population using the Latin Hypercube Sampling (LHS) technique. MSCA serves to guide SCA in obtaining a better local optimum in the exploitation phase with fast convergence based on an optimum value of the solution. Second, hybridization of the MSCA (HMSCA) and the Cuckoo …

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Crystal Structure And Site-Directed Mutagenesis Of Circular Bacteriocin Plantacyclin B21ag Reveals Cationic And Aromatic Residues Important For Antimicrobial Activity, Mian Gor, Ben Vezina, Roisín Mcmahon, Gordon King, Santosh Panjikar, Bernd H. Rehm, Jennifer L. Martin, Andrew Smith Jan 2020

Crystal Structure And Site-Directed Mutagenesis Of Circular Bacteriocin Plantacyclin B21ag Reveals Cationic And Aromatic Residues Important For Antimicrobial Activity, Mian Gor, Ben Vezina, Roisín Mcmahon, Gordon King, Santosh Panjikar, Bernd H. Rehm, Jennifer L. Martin, Andrew Smith

Deputy Vice-Chancellor (Research and Innovation) Papers

© 2020, The Author(s). Plantacyclin B21AG is a circular bacteriocin produced by Lactiplantibacillus plantarum B21 which displays antimicrobial activity against various Gram-positive bacteria including foodborne pathogens, Listeria monocytogenes and Clostridium perfringens. It is a 58-amino acid cyclised antimicrobial peptide, with the N and C termini covalently linked together. The circular peptide backbone contributes to remarkable stability, conferring partial proteolytic resistance and structural integrity under a wide temperature and pH range. Here, we report the first crystal structure of a circular bacteriocin from a food grade Lactobacillus. The protein was crystallised using the hanging drop vapour diffusion method and the structure …

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Evaluation Of The Ptw Microdiamond In Edge-On Orientation For Dosimetry In Small Fields, Owen Brace, Sultan Alhujaili, Jason Paino, Duncan Butler, Dean Wilkinson, Bradley M. Oborn, Anatoly B. Rosenfeld, Michael L. F Lerch, Marco Petasecca, Jeremy A. Davis Jan 2020

Evaluation Of The Ptw Microdiamond In Edge-On Orientation For Dosimetry In Small Fields, Owen Brace, Sultan Alhujaili, Jason Paino, Duncan Butler, Dean Wilkinson, Bradley M. Oborn, Anatoly B. Rosenfeld, Michael L. F Lerch, Marco Petasecca, Jeremy A. Davis

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine Purpose: The PTW microDiamond has an enhanced spatial resolution when operated in an edge-on orientation but is not typically utilized in this orientation due to the specifications of the IAEA TRS-483 code of practice for small field dosimetry. In this work the suitability of an edge-on orientation and advantages over the recommended face-on orientation will be presented. Methods: The PTW microDiamond in both orientations was compared on a Varian TrueBeam linac for: machine output factor (OF), …

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Modeling A Thick Hydrogenated Amorphous Silicon Substrate For Ionizing Radiation Detectors, Jeremy A. Davis, Maurizio Boscardin, Michele Crivellari, Livio Fano, Matthew Large, Mauro Menichelli, Arianna Morozzi, Francesco Moscatelli, Maria Movileanu-Ionica, Daniele Passeri, Marco Petasecca, Mauro Piccini, Alessandro Rossi, Andrea Scorzoni, Bailey Thompson, Giovanni Verzellesi, Nicolas Wyrsch Jan 2020

Modeling A Thick Hydrogenated Amorphous Silicon Substrate For Ionizing Radiation Detectors, Jeremy A. Davis, Maurizio Boscardin, Michele Crivellari, Livio Fano, Matthew Large, Mauro Menichelli, Arianna Morozzi, Francesco Moscatelli, Maria Movileanu-Ionica, Daniele Passeri, Marco Petasecca, Mauro Piccini, Alessandro Rossi, Andrea Scorzoni, Bailey Thompson, Giovanni Verzellesi, Nicolas Wyrsch

Faculty of Engineering and Information Sciences - Papers: Part B

© Copyright © 2020 Davis, Boscardin, Crivellari, Fanò, Large, Menichelli, Morozzi, Moscatelli, Movileanu-Ionica, Passeri, Petasecca, Piccini, Rossi, Scorzoni, Thompson, Verzellesi and Wyrsch. There is currently a renewed interest in hydrogenated amorphous silicon (a-Si:H) for use in particle detection applications. Whilst this material has been comprehensively investigated from a numerical perspective within the context of photovoltaic and imaging applications, the majority of work related to its application in particle detection has been limited to experimental studies. In this study, a material model to mimic the electrical and charge collection behavior of a-Si:H is developed using the SYNOPSYS©Technology Computer Aided Design (TCAD) …

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A Novel Monte Carlo-Based Neural Network Model For Electricity Load Forecasting, Binbin Yong, Zijian Xu, Jun Shen, Huaming Chen, Jianqing Wu, Fucun Li, Qingguo Zhou Jan 2020

A Novel Monte Carlo-Based Neural Network Model For Electricity Load Forecasting, Binbin Yong, Zijian Xu, Jun Shen, Huaming Chen, Jianqing Wu, Fucun Li, Qingguo Zhou

Faculty of Engineering and Information Sciences - Papers: Part B

The ongoing rapid growth of electricity over the past few decades greatly promotes the necessity of accurate electricity load forecasting. However, despite a great number of studies, electricity load forecasting is still an enormous challenge for its complexity. Recently, the developments of machine learning technologies in different research areas have demonstrated its great advantages. General Vector Machine (GVM) is a new machine learning model, which has been proven very effective in time series prediction. In this article, we firstly review the basic concepts and implementation of GVM. Then we apply it in electricity load forecasting, which is based on the …

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Apex2s: A Two-Layer Machine Learning Model For Discovery Of Host-Pathogen Protein-Protein Interactions On Cloud-Based Multiomics Data, Huaming Chen, Jun Shen, Lei Wang, Chi-Hung Chi Jan 2020

Apex2s: A Two-Layer Machine Learning Model For Discovery Of Host-Pathogen Protein-Protein Interactions On Cloud-Based Multiomics Data, Huaming Chen, Jun Shen, Lei Wang, Chi-Hung Chi

Faculty of Engineering and Information Sciences - Papers: Part B

No abstract provided.

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Aggregatable Certificateless Designated Verifier Signature, Pairat Thorncharoensri, Willy Susilo Jan 2020

Aggregatable Certificateless Designated Verifier Signature, Pairat Thorncharoensri, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part B

In recent years, the Internet of Things (IoT) devices have become increasingly deployed in many industries and generated a large amount of data that needs to be processed in a timely and efficient manner. Using aggregate signatures, it provides a secure and efficient way to handle large numbers of digital signatures with the same message. Recently, the privacy issue has been concerned about the topic of data sharing on the cloud. To provide the integrity, authenticity, authority, and privacy on the data sharing in the cloud storage, the notion of an aggregatable certificateless designated verifier signature scheme (ACLDVS) was proposed. …

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Quantitative Verification For Monitoring Event-Streaming Systems, Guoxin Su, Li Liu, Minjie Zhang, David Rosenblum Jan 2020

Quantitative Verification For Monitoring Event-Streaming Systems, Guoxin Su, Li Liu, Minjie Zhang, David Rosenblum

Faculty of Engineering and Information Sciences - Papers: Part B

IEEE High-performance data streaming technologies are increasingly adopted in IT companies to support the integration of heterogeneous and possibly distributed service systems and applications. Compared with the traditional message queuing middleware, a streaming platform enables the implementation of event-streaming systems (ESS) which include not only complex queues but also applications that transform and react to the streams of data. By analysing the centralised data streams, one can evaluate the Quality-of-Service for other systems and components that produce or consume the streams. We consider the exploitation of probabilistic model checking as a performance monitoring technique for ESS systems. Probabilistic model checking …

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The Mechanism And Effects Of Subgrade Fluidisation Under Ballasted Railway Tracks, Buddhima Indraratna, Mandeep Singh, Thanh Trung Nguyen Jan 2020

The Mechanism And Effects Of Subgrade Fluidisation Under Ballasted Railway Tracks, Buddhima Indraratna, Mandeep Singh, Thanh Trung Nguyen

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020, The Author(s). The rapid growth in railway infrastructure and the construction of high-speed heavy-haul rail network, especially on ground that is basically unsuitable, poses challenges for geotechnical engineers because a large part of the money invested in the development of railway lines is often spent on track maintenance. In fact around the world, the mud pumping of subgrade fines is one of the common reasons why track performance deteriorates and track stability is hindered. This article presents a series of laboratory tests to examine following aspects of mud pumping: (1) the mechanisms of subgrade fluidisation under undrained condition, …

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Synthesis And Characterization Of Additive Graphene Oxide Nanoparticles Dispersed In Water: Experimental And Theoretical Viscosity Prediction Of Non-Newtonian Nanofluid, Yang Xu, Quyen Nguyen, Omid Malekahmadi, Ramin Hadi, Zahra Jokar, Ali Mardani, Arash Karimipour, Ramin Ranjbarzadeh, Zhixiong Li, Quang Bach Jan 2020

Synthesis And Characterization Of Additive Graphene Oxide Nanoparticles Dispersed In Water: Experimental And Theoretical Viscosity Prediction Of Non-Newtonian Nanofluid, Yang Xu, Quyen Nguyen, Omid Malekahmadi, Ramin Hadi, Zahra Jokar, Ali Mardani, Arash Karimipour, Ramin Ranjbarzadeh, Zhixiong Li, Quang Bach

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 John Wiley & Sons, Ltd. Graphene oxide (GO) is a mixture of carbon, oxygen, and hydrogen. GO sheets used to make tough composite materials, thin films, and membranes. GO-water nanofluid's rheological behavior was investigated in this research. Various mass fractions: 1.0, 1.5, 2.0, 2.5, and 3.5 mg/ml; different temperature ranges: 25°C, 30°C, 35°C, 40°C, 45°C, and 50°C; and several shear ranges: 12.23, 24.46, 36.69, 61.15, 73.38, and 122.3 s−1 were studied. X-ray diffraction analysis (XRD), energy dispersive X-ray analysis (EDX), dynamic light scattering analysis (DLS), and Fourier-transform infrared (FTIR) tests studied to analyze phase and structure. Field emission …

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Enhanced Interface Strength In Steel-Nickel Bimetallic Component Fabricated Using Wire Arc Additive Manufacturing With Interweaving Deposition Strategy, Bintao Wu, Zhijun Qiu, Zengxi Stephen Pan, Kristin R. Carpenter, Tong Wang, Donghong Ding, Stephen Van Duin, Hui Jun Li Jan 2020

Enhanced Interface Strength In Steel-Nickel Bimetallic Component Fabricated Using Wire Arc Additive Manufacturing With Interweaving Deposition Strategy, Bintao Wu, Zhijun Qiu, Zengxi Stephen Pan, Kristin R. Carpenter, Tong Wang, Donghong Ding, Stephen Van Duin, Hui Jun Li

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 Realizing improved strength in composite metallic materials remains a challenge using conventional welding and joining systems due to the generation and development of brittle intermetallic compounds caused by complex thermal profiles during solidification. Here, wire arc additive manufacturing (WAAM) process was used to fabricate a steel-nickel structural component, whose average tensile strength of 634 MPa significantly exceeded that of feedstock materials (steel, 537 MPa and nickel, 455 MPa), which has not been reported previously. The as-fabricated sample exhibited hierarchically structural heterogeneity due to the interweaving deposition strategy. The improved mechanical response during tensile testing was due to the …

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Lane Work-Schedule Of Toll Station Based On Queuing Theory And Pso-Lstm Model, Peng Wang, Jiandong Zhao, Yuan Gao, Miguel Sotelo, Zhixiong Li Jan 2020

Lane Work-Schedule Of Toll Station Based On Queuing Theory And Pso-Lstm Model, Peng Wang, Jiandong Zhao, Yuan Gao, Miguel Sotelo, Zhixiong Li

Faculty of Engineering and Information Sciences - Papers: Part B

© 2013 IEEE. A reasonable lane work-schedule in each time period can not only guarantee the traffic efficiency of toll stations, but also reduce the operating cost of toll stations. This paper proposes a comprehensive solution for lane work plan. Firstly, the average queue length is selected as a good index for measuring the congestion of toll station. And then, based on the queuing theory, the service level of toll station is divided into four levels according to the relationship between the average queue length and traffic capacity. Secondly, based on the toll data, a toll station congestion prediction model …

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A Review Of Secondary Flow In Inertial Microfluidics, Qianbin Zhao, Dan Yuan, Jun Zhang, Weihua Li Jan 2020

A Review Of Secondary Flow In Inertial Microfluidics, Qianbin Zhao, Dan Yuan, Jun Zhang, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 by the authors. Inertial microfluidic technology, which can manipulate the target particle entirely relying on the microchannel characteristic geometry and intrinsic hydrodynamic effect, has attracted great attention due to its fascinating advantages of high throughput, simplicity, high resolution and low cost. As a passive microfluidic technology, inertial microfluidics can precisely focus, separate, mix or trap target particles in a continuous and high-flow-speed manner without any extra external force field. Therefore, it is promising and has great potential for a wide range of industrial, biomedical and clinical applications. In the regime of inertial microfluidics, particle migration due to inertial …

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Thermal Conductivity Enhancement Of Nanofluid By Adding Multiwalled Carbon Nanotubes: Characterization And Numerical Modeling Patterns, Congcong Du, Quyen Nguyen, Omid Malekahmadi, Ali Mardani, Zahra Jokar, Elmira Babadi, Annunziata D'Orazio, Arash Karimipour, Zhixiong Li, Quang Bach Jan 2020

Thermal Conductivity Enhancement Of Nanofluid By Adding Multiwalled Carbon Nanotubes: Characterization And Numerical Modeling Patterns, Congcong Du, Quyen Nguyen, Omid Malekahmadi, Ali Mardani, Zahra Jokar, Elmira Babadi, Annunziata D'Orazio, Arash Karimipour, Zhixiong Li, Quang Bach

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 John Wiley & Sons, Ltd. Nanofluid is divided in two major section, mono nanofluid (MN) and hybrid nanofluid (HN). MN is created when a solid nanoparticle disperses in a fluid, whereas HN has more than one solid nanomaterial. In this research, iron (III) oxide (Fe3O4) is MN, and Fe3O4 plus multiwalled carbon nanotube (MWCNT) is HN, whereas both are mixed and dispersed into the water basefluid. Thermal conductivity (TC) of Fe3O4/water and MWCNT/Fe3O4/water was measured after preparation and numerical model performed on the resulted data. After that, field emission scanning electron microscope (FESEM) was studied for microstructural observation …

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Influence Of Backward-Facing Step On The Mixing Efficiency Of Multi Microjets At Supersonic Flow, Zhixiong Li, R Moradi, Seyed Marashi, Houman Babazadeh, Gautam Choubey Jan 2020

Influence Of Backward-Facing Step On The Mixing Efficiency Of Multi Microjets At Supersonic Flow, Zhixiong Li, R Moradi, Seyed Marashi, Houman Babazadeh, Gautam Choubey

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 IAA The injection of the fuel is a highly important process for the enhancement of the scramjets. In this article, the presence of the backward-facing step on the mixing of the multi-fuel jets is expansively studied. The primary attention of this article is to scrutinize the flow feature of the fuel jet under the backward-facing step. The mixing mechanism of the fuel is also studied to compare this injection system with conventional methods. To do this, a 3-dimensional model is chosen to consider the real physic of the problem. Reynolds Average Navier-Stocks equations are solved with a computational …

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Influence Of White Etching Layer On Rolling Contact Behavior At Wheel-Rail Interface, Qinglin Lian, Guanyu Deng, Hongtao Zhu, Hui Jun Li, Xi Wang, Zhiming Liu Jan 2020

Influence Of White Etching Layer On Rolling Contact Behavior At Wheel-Rail Interface, Qinglin Lian, Guanyu Deng, Hongtao Zhu, Hui Jun Li, Xi Wang, Zhiming Liu

Faculty of Engineering and Information Sciences - Papers: Part B

The existence of narrow and brittle white etching layers (WELs) on the rail surface is often linked with the formation of rail defects such as squats and studs, which play the key roles in rail surface degradation and tribological performance. In the present study, a systematic investigation on stress/strain distribution and fatigue life of the WEL during wheel-rail rolling contact was conducted based on a numerical model considering the realistic wheel geometry. This is the first study considering the influence of rail materials, loading pressure, frictional condition, WEL geometry (a/b), and slip ratio (Sr) in the practical service conditions at …

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Numerical Assessment On The Hydrothermal Behavior And Irreversibility Of Mgo-Ag/Water Hybrid Nanofluid Flow Through A Sinusoidal Hairpin Heat-Exchanger, Zhixiong Li, Amin Shahsavar, Kavian Niazi, Abdullah Al-Rashed, Sara Rostami Jan 2020

Numerical Assessment On The Hydrothermal Behavior And Irreversibility Of Mgo-Ag/Water Hybrid Nanofluid Flow Through A Sinusoidal Hairpin Heat-Exchanger, Zhixiong Li, Amin Shahsavar, Kavian Niazi, Abdullah Al-Rashed, Sara Rostami

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 Elsevier Ltd The aim of this work is to study the hydrothermal and irreversibility characteristics in forced convection flow of Ag-MgO/water hybrid nanofluid through a sinusoidal hairpin heat-exchanger, numerically. The impact of nano-additive concentration (φ), Reynolds number (Re) and amplitude of the sinusoidal tube are investigated on the heat-exchanger performance form both the first law and second law points of view. The considered performance matrices are heat transfer rate, total heat transfer coefficient, heat-exchanger effectiveness, pressure loss, pumping power as well as the irreversibilities due to flow friction and heat transfer. The findings indicated that boosting the Re …

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Design Of (Hf,Ta)Fe2/Fe Composite With Zero Thermal Expansion Covering Room Temperature, Dongyu Cen, Bin Wang, Ruixue Chu, Yuanyuan Gong, Guizhou Xu, Fenghua Chen, Feng Xu Jan 2020

Design Of (Hf,Ta)Fe2/Fe Composite With Zero Thermal Expansion Covering Room Temperature, Dongyu Cen, Bin Wang, Ruixue Chu, Yuanyuan Gong, Guizhou Xu, Fenghua Chen, Feng Xu

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 Acta Materialia Inc. MgZn2-type (Hf,Ta)Fe2 is a typical negative-thermal-expansion system, which expands during the establishment of ferromagnetic ordering in cooling. This abnormal behavior suggests that (Hf,Ta)Fe2 is a potential ingredient to produce a composite with zero thermal expansion. In this work, we find that the as-cast (Hf,Ta)Fe2 have Fe-rich grain boundaries, which disappear after annealing. It inspires us to produce a (Hf,Ta)Fe2/Fe composite by adding extra Fe in nonstoichiometric composition without annealing. After carefully tuning Hf/Ta ratio and Fe concentration, room-temperature zero-thermal-expansion is achieved in the sample with a composition of Hf0.80Ta0.20Fe2.5.

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Effect Of Copper Nanoparticles On Thermal Behavior Of Water Flow In A Zig-Zag Nanochannel Using Molecular Dynamics Simulation, Yu Jiang, Sadegh Dehghan, Arash Karimipour, Davood Toghraie, Zhixiong Li, Iskander Tlili Jan 2020

Effect Of Copper Nanoparticles On Thermal Behavior Of Water Flow In A Zig-Zag Nanochannel Using Molecular Dynamics Simulation, Yu Jiang, Sadegh Dehghan, Arash Karimipour, Davood Toghraie, Zhixiong Li, Iskander Tlili

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 Elsevier Ltd Molecular dynamics (MD) simulation is one of the most common simulation methods which predict the dynamical and thermodynamical properties of atomic structures based on classical Newton's laws. In this study, the effect of copper nanoparticles on the thermal behavior of the fluid in zig-zag nanochannel was investigated using molecular dynamics simulation. In our simulations, water molecules were used to model the base fluid, and platinum atoms were used to model the nanochannel walls. To investigate the effects of copper nanoparticles on the base fluid, physical quantities such as potential energy, density, velocity, temperature profiles, and finally, …

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Disaggregated Level Child Morbidity In Bangladesh: An Application Of Small Area Estimation Method, Sumonkanti Das, Bappi Kumar, Luthful Kawsar Jan 2020

Disaggregated Level Child Morbidity In Bangladesh: An Application Of Small Area Estimation Method, Sumonkanti Das, Bappi Kumar, Luthful Kawsar

Faculty of Engineering and Information Sciences - Papers: Part B

2020 Das et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Acute respiratory infection (ARI) and diarrhoea are two major causes of child morbidity and mortality in Bangladesh. National and regional level prevalence of ARI and diarrhoea are calculated from nationwide surveys; however, prevalence at micro-level administrative units (say, district and sub-district) is not possible due to lack of sufficient data at those levels. In such a case, small area estimation (SAE) methods …

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Conditions For The Existence, Identification And Calculus Rules Of The Threshold Of Prox-Boundedness, Chayne Planiden Jan 2020

Conditions For The Existence, Identification And Calculus Rules Of The Threshold Of Prox-Boundedness, Chayne Planiden

Faculty of Engineering and Information Sciences - Papers: Part B

2020, Springer-Verlag GmbH Germany, part of Springer Nature. This note advances knowledge of the threshold of prox-boundedness of a function; an important concern in the use of proximal point optimization algorithms and in determining the existence of the Moreau envelope of the function. In finite dimensions, we study general prox-bounded functions and then focus on some useful classes such as piecewise functions and Lipschitz continuous functions. The thresholds are explicitly determined when possible and bounds are established otherwise. Some calculus rules are constructed; we consider functions with known thresholds and find the thresholds of their sum and composition.

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