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Full-Text Articles in Engineering
H∞ Delayed Tracking Protocol Design Of Nonlinear Singular Multi-Agent Systems Under Markovian Switching Topology, Xiangli Jiang, Guihua Xia, Zhiguang Feng, Zhengyi Jiang
H∞ Delayed Tracking Protocol Design Of Nonlinear Singular Multi-Agent Systems Under Markovian Switching Topology, Xiangli Jiang, Guihua Xia, Zhiguang Feng, Zhengyi Jiang
Faculty of Engineering and Information Sciences - Papers: Part B
© 2020 Elsevier Inc. The consensus tracking of singular multi-agent systems (MASs) with Lipschitz-type nonlinearities and exogenous disturbances is researched in this paper. Governed by a Markov chain, the network interaction randomly switches in a directed graph set, where the directed spanning tree is not contained in each graph while exists in the union rooting at the leader node. By utilizing a collection of in-neighbors’ information that involves communication delay, the intention is to design a protocol such that the resultant consensus error system is stochastic admissible with an H∞ disturbance attenuation level. Based on algebraic graph theory, stochastic admissibility …
Numerical Modelling Of Track Behavior Capturing Particle Breakage Under Dynamic Loading, Ngoc Trung Ngo, Buddhima Indraratna
Numerical Modelling Of Track Behavior Capturing Particle Breakage Under Dynamic Loading, Ngoc Trung Ngo, Buddhima Indraratna
Faculty of Engineering and Information Sciences - Papers: Part B
No abstract provided.
Thermal Features Vis A Vis Strain Features Of Fracturing Process In Jointed Rock Layer Under Concentrated Load, Haiqing Yang, Bolong Liu, Shivakumar Karekal
Thermal Features Vis A Vis Strain Features Of Fracturing Process In Jointed Rock Layer Under Concentrated Load, Haiqing Yang, Bolong Liu, Shivakumar Karekal
Faculty of Engineering and Information Sciences - Papers: Part B
In case of earthquakes and crustal movement, the concentration of impounding load over a large region of crust can cause disturbances to the stratum. In order to quantitatively investigate crack initiation, propagation and coalescence processes of jointed stratum based on thermal variations caused by concentrated mechanical loading, a series of indention tests were performed on granite specimens. In the experiment, fracture process and resulting infrared radiation fields of specimens were respectively recorded by synchronized digital image correlation system and infrared camera. Then, thermal characteristics of mixed shear-tensile and tensile conical crack were analyzed. Experimental results indicate that the highlighted temperature …
An Adaptive Feed-Forward Phase Locked Loop For Grid Synchronization Of Renewable Energy Systems Under Wide Frequency Deviations, Aravind Chellachi Kathiresan, Jeyaraj Pandiarajan, Asokan Sivaprakash, Thanikanti Sudhakar Babu, Md Rabiul Islam
An Adaptive Feed-Forward Phase Locked Loop For Grid Synchronization Of Renewable Energy Systems Under Wide Frequency Deviations, Aravind Chellachi Kathiresan, Jeyaraj Pandiarajan, Asokan Sivaprakash, Thanikanti Sudhakar Babu, Md Rabiul Islam
Faculty of Engineering and Information Sciences - Papers: Part B
Synchronization is a crucial problem in the grid-connected inverter’s control and operation. A phase-locked loop (PLL) is a typical grid synchronization strategy, which ought to have a high resistance to power system uncertainties since its sensitivity influences the generated reference signal. The traditional PLL catches the phase and frequency of the input signal via the feedback loop filter (LF). In general, to enhance the steady-state capability during distorted grid conditions generally, a filter tuned for nominal frequency is used. This PLL corrects large frequency deviations around the nominal frequency, which increases the PLL’s locking time. Therefore, this paper presents an …
A Laboratory Study On Fluidization Of Subgrade Under Cyclic Train Loading, Buddhima Indraratna, Mandeep Singh, Thanh Trung Nguyen, Serge Leroueil, Aruni Lakmali Abeywickrama Bamunusing Kankanamge, Richard B. Kelly, Tim Neville
A Laboratory Study On Fluidization Of Subgrade Under Cyclic Train Loading, Buddhima Indraratna, Mandeep Singh, Thanh Trung Nguyen, Serge Leroueil, Aruni Lakmali Abeywickrama Bamunusing Kankanamge, Richard B. Kelly, Tim Neville
Faculty of Engineering and Information Sciences - Papers: Part B
A long term issue that has hampered the efficient operation of heavy haul tracks is the migration of fluidized fines from the shallow soft subgrade to the overlying ballast, i.e., mud pumping. This paper presents a series of undrained cyclic triaxial tests, where realistic cyclic loading conditions were simulated at low confining pressure that is typical of shallow subgrade beneath a ballast track. Subgrade soil specimens with a low plasticity index collected from a field site with recent history of mud pumping were tested at frequencies from 1.0 to 5.0 Hz and a cyclic stress ratio (CSR) from 0.1 to …
Improved Performance Of Ballasted Tracks Under Impact Loading By Recycled Rubber Mats, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn
Improved Performance Of Ballasted Tracks Under Impact Loading By Recycled Rubber Mats, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn
Faculty of Engineering and Information Sciences - Papers: Part B
Ballasted tracks at transition locations such as approaches to bridges and road crossings experience increasing degradation and deformation due to dynamic and high impact forces, a key factor that decreases the stability and longevity of railroads. One solution to minimise ballast degradation at the transition zones is using rubber energy absorbing drainage sheets (READS) manufactured from recycled tyres. When placed beneath the ballast layer, READS distributes the load over wider area and attenuate of the load over a longer duration thus decreasing maximum stress, apart from reducing the energy transferred to the ballast and other substructure components. Subsequently, the track …
Performance Evaluation Of Intermittently Cfrp Wrapped Square And Circularised Square Reinforced Concrete Columns Under Different Loading Conditions, Anh Duc Mai, M Neaz Sheikh, Muhammad N. S Hadi
Performance Evaluation Of Intermittently Cfrp Wrapped Square And Circularised Square Reinforced Concrete Columns Under Different Loading Conditions, Anh Duc Mai, M Neaz Sheikh, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
This paper presents the results of an experimental investigation on square and circularised square rein-forced concrete (RC) columns intermittently wrapped with carbon fibre reinforced polymer (CFRP)under different loading conditions. Twelve RC specimens consisting of eight square RC specimenswith 150mm150mm cross-section and 800mm height and four circularised square RC specimenswith 212mm diameter and 800 mm height were tested under concentric axial load, eccentric axialload and four-point flexural load. The test results showed that intermittent wrapping increased thestrength and ductility of square RC specimens. The test results also showed that circularisation com-bined with intermittent wrapping significantly improved the strength and ductility of …
Experimental And Numerical Studies Of Square Concrete-Filled Double Steel Tubular Short Columns Under Eccentric Loading, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi
Experimental And Numerical Studies Of Square Concrete-Filled Double Steel Tubular Short Columns Under Eccentric Loading, Mizen Ahmed, Qing Quan Liang, Vipulkumar I. Patel, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
Square concrete-filled double steel tubular (CFDST) beam-columns consisting of an internal circular steel tube have increasingly been utilized in composite building structures because of their high structural performance. This paper describes experimental and numerical studies on the structural responses of square thin-walled CFDST columns loaded eccentrically. Tests on twenty short square CFDST columns were undertaken that included sixteen columns under eccentric loading and four columns under concentric loading. The parameters examined in the experiments included the cross-sectional dimensions, the width-to-thickness ratios of outer and internal tubes and loading eccentricity. The measured ultimate strengths, load-shortening responses, load-lateral displacement curves, stress-strain curves …
Performance Evaluation Of Non-Gps Based Localization Techniques Under Shadowing Effects, Ngoc M. Nguyen, Le Chung Tran, Farzad Safaei, Son Lam Phung, Peter James Vial, Nam N. Huynh, Anne N. Cox, Theresa Harada, Johan Barthelemy
Performance Evaluation Of Non-Gps Based Localization Techniques Under Shadowing Effects, Ngoc M. Nguyen, Le Chung Tran, Farzad Safaei, Son Lam Phung, Peter James Vial, Nam N. Huynh, Anne N. Cox, Theresa Harada, Johan Barthelemy
Faculty of Engineering and Information Sciences - Papers: Part B
Non-GPS localization has gained much interest from researchers and industries recently because GPS might fail to meet the accuracy requirements in shadowing environments. The two most common range-based non-GPS localization methods, namely Received Signal Strength Indicator (RSSI) and Angle-of-Arrival (AOA), have been intensively mentioned in the literature over the last decade. However, an in-depth analysis of the weighted combination methods of AOA and RSSI in shadowing environments is still missing in the state-of-the-art. This paper proposes several weighted combinations of the two RSSI and AOA components in the form of pAOA + qRSSI, devises the mathematical model for analyzing shadowing …
Chemical Clogging Of Granular Media Under Acidic Groundwater Conditions-Experimental Simulation, Buddhima Indraratna, Subhani Kanchanama Medawela, Senura Athuraliya, Ana Heitor, Pankaj Baral
Chemical Clogging Of Granular Media Under Acidic Groundwater Conditions-Experimental Simulation, Buddhima Indraratna, Subhani Kanchanama Medawela, Senura Athuraliya, Ana Heitor, Pankaj Baral
Faculty of Engineering and Information Sciences - Papers: Part B
Generation of acidic groundwater attributed to pyrite oxidation in low-lying acid sulfate soil causes substantial damage to the soil-water environment and civil infrastructure. The installation of Permeable Reactive Barrier (PRB) is a frontier technology in the field of acid neutralisation and for removing toxic heavy metal cations, e.g. soluble Fe and Al. This study aims to assess the potential of limestone (calcite) aggregates as the PRB's main reactive material in low-lying pyritic land. During long-term laboratory column experiments, a significant capacity of limestone for removing the contaminant chemical species was observed. Nevertheless, the formation of secondary mineral precipitates upon geochemical …
Maximum Axial Load Carrying Capacity Of Fibre Reinforced-Polymer (Frp) Bar Reinforced Concrete Columns Under Axial Compression, Hayder Alaa Hasan, M Neaz Sheikh, Muhammad N. S Hadi
Maximum Axial Load Carrying Capacity Of Fibre Reinforced-Polymer (Frp) Bar Reinforced Concrete Columns Under Axial Compression, Hayder Alaa Hasan, M Neaz Sheikh, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
In this study, a new equation is proposed to compute the maximum axial load carrying capacity of FRP bar reinforced concrete columns under axial compression. The equation proposed in this study was critically compared with the equations proposed in the previous research studies using a wide range of experimental data taken from the available literature. In general, it was found that computing the contribution of the FRP longitudinal bars in concrete columns based on the modulus of elasticity (stiffness) of the FRP bars provides more rational predictions than computing the contribution of the FRP longitudinal bars based on the ultimate …
Probing Fretting Performance Of Dlc And Mos2 Films Under Fluid Lubrication, Wenhua Zhuang, Hao Li, Wen Li, Xiaoqiang Fan, Jifan He, Zhenbing Cai, Wang Fu, Guangan Zhang, Shanhong Wan, Minhao Zhu
Probing Fretting Performance Of Dlc And Mos2 Films Under Fluid Lubrication, Wenhua Zhuang, Hao Li, Wen Li, Xiaoqiang Fan, Jifan He, Zhenbing Cai, Wang Fu, Guangan Zhang, Shanhong Wan, Minhao Zhu
Faculty of Engineering and Information Sciences - Papers: Part B
Transition from onefold to synergistic lubrication for solving fretting wear and fatigue problems is of great practical significance, because fluids can regulate fretting regime for minimizing wear, solid films can restrain nucleation and formation of crack. Here synergistic lubrication coatings were prepared using diamond-like carbon (DLC) and molybdenum disulfide (MoS2) films as anti-wear/fatigue layer, and high-performance lubricants (including silicone oil, ionic liquids, multialkylated cyclopentanes and perfluoropolyethers (PFPE)) as flowable lubrication layer. Their fretting performance was evaluated in detail and fretting mechanism was revealed by surface/interface analysis techniques. Results determine the synergistic lubrication coatings with good anti-wear and anti-fatigue abilities, deriving …
Fiber Element Simulation Of Interaction Behavior Of Local And Global Buckling In Axially Loaded Rectangular Concrete-Filled Steel Tubular Slender Columns Under Fire Exposure, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi
Fiber Element Simulation Of Interaction Behavior Of Local And Global Buckling In Axially Loaded Rectangular Concrete-Filled Steel Tubular Slender Columns Under Fire Exposure, Ghanim Mohammed Kamil, Qing Quan Liang, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part B
Slender rectangular thin-walled concrete-filled steel tubular (CFST) columns in composite building structures exposed to fire may experience the interaction of local and global buckling. Numerical investigations on the interaction buckling responses of such columns under fire exposure have been rarely reported. This paper describes a fiber-based computational model for the prediction of the fire-resistance and interaction responses of local and global buckling of concentrically-loaded slender CFST columns made of rectangular sections exposed to fire. The thermal analysis is undertaken to calculate the distribution of temperatures in the column cross-section considering the effects of the air gap between concrete and steel, …
Application Of Geoinclusions For Sustainable Rail Infrastructure Under Increased Axle Loads And Higher Speeds, Buddhima Indraratna, Fernanda Bessa Ferreira, Yujie Qi, Ngoc Trung Ngo
Application Of Geoinclusions For Sustainable Rail Infrastructure Under Increased Axle Loads And Higher Speeds, Buddhima Indraratna, Fernanda Bessa Ferreira, Yujie Qi, Ngoc Trung Ngo
Faculty of Engineering and Information Sciences - Papers: Part B
Given the ongoing demand for faster trains for carrying heavier loads, conventional ballasted railroads require considerable upgrading in order to cope with the increasing traffic-induced stresses. During train operations, ballast deteriorates due to progressive breakage and fouling caused by the infiltration of fine particles from the surface or mud-pumping from the underneath layers (e.g. sub-ballast, sub-grade), which decreases the load bearing capacity, impedes drainage and increases the deformation of ballasted tracks. Suitable ground improvement techniques involving geosynthetics and resilient rubber sheets are commonly employed to enhance the stability and longevity of rail tracks. This keynote paper focuses mainly on research …
Vibration Attenuation At Rail Joints Through Under Sleeper Pads, Sakdirat Kaewunruen, Akira Aikawa, Alex M. Remennikov
Vibration Attenuation At Rail Joints Through Under Sleeper Pads, Sakdirat Kaewunruen, Akira Aikawa, Alex M. Remennikov
Faculty of Engineering and Information Sciences - Papers: Part B
Modern railway tracks require electrification to power the trains and signaling systems to detect near real-time location of trains on railway networks. Such systems require the rail to carry and return the residual electricity back to substation, while enable signals to transfer within a track circuit. This track circuit requires rail jo ints to divide and insulate each loop of the circuit. Such the rail joints often generate impact transient dynamics to track systems. This paper presents the filed investigation into the vibration attenuation characteristic of under sleeper pads (USPs), which are the component installed under the concrete sleepers generally …
Use Of Synthetic Inclusions For Enhanced Behaviour Of Railway Ballast Under Impact Loading, Fernanda Bessa Ferreira, Buddhima Indraratna
Use Of Synthetic Inclusions For Enhanced Behaviour Of Railway Ballast Under Impact Loading, Fernanda Bessa Ferreira, Buddhima Indraratna
Faculty of Engineering and Information Sciences - Papers: Part B
Ballasted rail tracks form one of the largest worldwide networks catering to passenger and freight transportation. However, track deterioration associated with severe dynamic wheel loads is inevitable over the years leading to high maintenance costs. Geosynthetics and energy-absorbing rubber mats have increasingly been applied in rail track foundations to improve track stability and reduce the life-cycle cost of the railway system. This paper presents the results of an experimental study carried out using a high-capacity drop-weight impact testing apparatus to investigate the deformation and degradation response of railway ballast under impact loading conditions. The effectiveness of the geogrid reinforcement in …
High Temperature Oxidation Of Indefinite Chill Roll Material Under Dry And Humid Atmospheres, Liang Hao, Zhengyi Jiang, Zhixin Chen, Dongbin Wei, Xiawei Cheng, Jingwei Zhao, Ming Luo, Li Ma, Suzhen Luo, Laizhu Jiang
High Temperature Oxidation Of Indefinite Chill Roll Material Under Dry And Humid Atmospheres, Liang Hao, Zhengyi Jiang, Zhixin Chen, Dongbin Wei, Xiawei Cheng, Jingwei Zhao, Ming Luo, Li Ma, Suzhen Luo, Laizhu Jiang
Faculty of Engineering and Information Sciences - Papers: Part B
In this paper, the isothermal oxidation of the indefinite chill (IC) roll is investigated by using a thermogravimetric analyzer (TGA) from 550 to 700 °C under dry and humid atmospheres. It is found that the oxidation kinetics follow a linear trend and the oxide scale consists of two layers after the oxidation in dry air but three layers in humid air above 600 °C. In dry air, the graphite is covered by the oxide scale above 650 °C. The water vapor accelerates the oxidation of the matrix and the graphite. The graphite is covered by the extension of the oxide …