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Full-Text Articles in Engineering

Improved Performance Of Ballasted Tracks Under Impact Loading By Recycled Rubber Mats, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn Jan 2019

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 …


Use Of Geogrids And Recycled Rubber In Railroad Infrastructure For Enhanced Performance, Buddhima Indraratna, Yujie Qi, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Tim Neville, Fernanda Bessa Ferreira, Amir Shahkolahi Jan 2019

Use Of Geogrids And Recycled Rubber In Railroad Infrastructure For Enhanced Performance, Buddhima Indraratna, Yujie Qi, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Tim Neville, Fernanda Bessa Ferreira, Amir Shahkolahi

Faculty of Engineering and Information Sciences - Papers: Part B

Railway tracks are conventionally built on compacted ballast and structural fill layers placed above the natural (subgrade) foundation. However, during train operations, track deteriorations occur progressively due to ballast degradation. The associated track deformation is usually accompanied by a reduction in both load bearing capacity and drainage, apart from imposing frequent track maintenance. Suitable ground improvement techniques involving plastic inclusions (e.g., geogrids) and energy absorbing materials (e.g., rubber products) to enhance the stability and longevity of tracks have become increasingly popular. This paper presents the outcomes from innovative research and development measures into the use of plastic and rubber elements …


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 Jan 2019

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 …


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 Jan 2019

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 …


Frequency Domain Characterization And Performance Bounds Of Alms Loop For Rf Self-Interference Cancellation, Anh Tuyen Le, Le Chung Tran, Xiaojing Huang, Y J. Guo, J (Yiannis) Vardaxoglou Jan 2019

Frequency Domain Characterization And Performance Bounds Of Alms Loop For Rf Self-Interference Cancellation, Anh Tuyen Le, Le Chung Tran, Xiaojing Huang, Y J. Guo, J (Yiannis) Vardaxoglou

Faculty of Engineering and Information Sciences - Papers: Part B

Analog Least Mean Square (ALMS) loop is a promising method to cancel self-interference (SI) in in-band fullduplex (IBFD) systems. In this paper, the steady state analyses of the residual SI powers in both analog and digital domains are firstly derived. Eigenvalue decomposition is then utilized to investigate the frequency domain characteristics of the ALMS loop. Our frequency domain analyses prove that the ALMS loop has an effect of amplifying the frequency components of the residual SI at the edges of the signal spectrum in the analog domain. However, the matched filter in the receiver chain will reduce this effect, resulting …


Performance Simulation And Evaluation Of Net Zero Energy Buildings In An Australian Coastal Climate, Joel Anderson, Duane A. Robinson, Zhenjun Ma Jan 2019

Performance Simulation And Evaluation Of Net Zero Energy Buildings In An Australian Coastal Climate, Joel Anderson, Duane A. Robinson, Zhenjun Ma

Faculty of Engineering and Information Sciences - Papers: Part B

Net zero energy buildings (NZEB) are becoming more common, and as new energy saving designs and technologies become available, the ability to estimate overall energy use and understand the impact on operation of building appliances will become important. This paper outlines simulation results of performance improvements achieved by modifying various components (glazing, lighting, thermal comfort settings) of two tertiary education NZEBs and a typical modern commercial building. The DesignBuilder models' thermal performance and energy consumption were validated using real data from case study buildings. The work shows validating models of smaller, less conven-tional, buildings is more difficult than for larger …


Dual Effects Of Tisio4composite Nanoparticles On Dispersionstability And Lubrication Performance Of Vegetable Oil‐In‐Water Emulsions, Reza Taheri, Buyung Kosasih, Hongtao Zhu, Anh Kiet Tieu Jan 2019

Dual Effects Of Tisio4composite Nanoparticles On Dispersionstability And Lubrication Performance Of Vegetable Oil‐In‐Water Emulsions, Reza Taheri, Buyung Kosasih, Hongtao Zhu, Anh Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part B

Vegetable oil-in-water emulsions are potential metal-working lubricants. These emulsions are susceptible to oil-water phase separation due to the oil droplets' coalescence. In this study, we enhance the dispersion stability and lubricity of such emulsions with TiSiO4 nanoparticles (NPs). With 1 vol% soybean oil, stable emulsions are obtained with 0.25 to 0.75 wt% NPs, attributed to formation of shielding layers of NPs around the droplets. Lowest friction and wear are obtained without and with 0.25 wt% NPs, respectively. With increasing the NPs' mass fraction, NP-shielded droplets become less attracted to metal surfaces. Association of NPs within boundary film is also found …


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 Jan 2019

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 …


Study On Performance Evaluation Of Co2 Heat Pump System Integrated With Thermal Energy Storage For Space Heating, Zhihua Wang, Yuxin Zheng, Fenghao Wang, Mengjie Song, Zhenjun Ma Jan 2019

Study On Performance Evaluation Of Co2 Heat Pump System Integrated With Thermal Energy Storage For Space Heating, Zhihua Wang, Yuxin Zheng, Fenghao Wang, Mengjie Song, Zhenjun Ma

Faculty of Engineering and Information Sciences - Papers: Part B

CO2 heat pumps have drawn a great deal of attention owing to their advantages of high efficiency and environmental friendly for heating water under low ambient temperature. However, the system performance is not desirable and shows a lower COP for space heating, especially for a radiator as heating terminal, due to the higher inlet water temperature at the gas cooler, which causes a large throttle loss when the refrigerant flow through the throttling device. To tackle this issue, a transcritical CO2 heat pump system integrated with thermal energy storage (TES) systems was developed in this paper. The heating performance of …


Influence Of Soil Clogging On The Performance Of Jute Fibre Drains Installed In Ballina Clay, Thanh Trung Nguyen, Buddhima Indraratna, John Philip Carter Jan 2019

Influence Of Soil Clogging On The Performance Of Jute Fibre Drains Installed In Ballina Clay, Thanh Trung Nguyen, Buddhima Indraratna, John Philip Carter

Faculty of Engineering and Information Sciences - Papers: Part B

Biodegradable prefabricated vertical drains (BPVD) made from naturally occurring materials such as jute and coconut (coir) fibre not only have favourable engineering characteristics but also not detri-mental to the natural environment thanks to their biodegradability. Although the use of these natural fibre drains has been proposed for several decades, their application is still very limited. One of major reasons for this is because they are usually composed of individual fibres with large openings which can trap fine soils while discharging pore pressure, consequently reducing the hydraulic conductivity of the drain. This study therefore aims to clarify how soil can clog …


Improved Performance Of Ballasted Tracks At Transition Zones: A Review Of Experimental And Modelling Approaches, Buddhima Indraratna, Muhammad Babar Sajjad, Ngoc Trung Ngo, A Correia, Richard B. Kelly Jan 2019

Improved Performance Of Ballasted Tracks At Transition Zones: A Review Of Experimental And Modelling Approaches, Buddhima Indraratna, Muhammad Babar Sajjad, Ngoc Trung Ngo, A Correia, Richard B. Kelly

Faculty of Engineering and Information Sciences - Papers: Part B

Track transitionssuch as bridge approaches, road crossings and shifts from slab track to ballasted track are common locations wheretrack degradation accelerates due to dynamic and high impact forces; as a consequence there is higher differential settlement. Thesetypes of discontinuities cause an abrupt change in the structural responseof the track due mainly tovariations in stiffness and track damping. Track transitionzones are prone to an accelerated deterioration of track material and geometrythat leads to increased maintenance costs.Track deteriorationalso leads to vehicle degradation due to enhanced acceleration, low frequency oscillation, and high frequency vibrations. While ballastdeterioration is amajor factor affecting thestability and longevity …


Speech Interfaces And Pilot Performance: A Meta-Analysis, Kenneth A. Ward Jan 2019

Speech Interfaces And Pilot Performance: A Meta-Analysis, Kenneth A. Ward

International Journal of Aviation, Aeronautics, and Aerospace

As the aviation industry modernizes, new technology and interfaces must support growing aircraft complexity without increasing pilot workload. Natural language processing presents just such a simple and intuitive interface, yet the performance implications for use by pilots remain unknown. A meta-analysis was conducted to understand performance effects of using speech and voice interfaces in a series of pilot task analogs. The inclusion criteria selected studies that involved participants performing a demanding primary task, such as driving, while interacting with a vehicle system to enter numbers, dial radios, or enter a navigation destination. Compared to manual system interfaces, voice interfaces reduced …