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Full-Text Articles in Engineering
Contextual Effects In Modeling For Small Domain Estimation, Mohammad-Reza Namazi-Rad, David G. Steel
Contextual Effects In Modeling For Small Domain Estimation, Mohammad-Reza Namazi-Rad, David G. Steel
SMART Infrastructure Facility - Papers
Many different Small Area Estimation (SAE) methods have been proposed to overcome the challenge of findingreliable estimates for small domains. Often, the required data for various research purposes are available at differentlevels of aggregation. Based on the available data, individual-level or aggregated-level models are used in SAE.However, parameter estimates obtained from individual and aggregated level analysis may be different, in practice.This may happen due to some substantial contextual or area-level effects in the covariates which may be misspecifiedin individual-level analysis. If small area models are going to be interpretable in practice, possible contextualeffects should be included. Ignoring these effects leads …
Investigating The Effects Of Pounding For Inelastic Base Isolated Adjacent Buildings Under Earthquake Excitations, Mehmet Uz, Muhammad N. S Hadi
Investigating The Effects Of Pounding For Inelastic Base Isolated Adjacent Buildings Under Earthquake Excitations, Mehmet Uz, Muhammad N. S Hadi
Faculty of Engineering - Papers (Archive)
In this study, an investigation is carried out to analyse the earthquake induced pounding be-tween two insufficiently separated base isolated buildings considering the inelastic behaviour of the struc-tures’ response. The buildings are modelled as a four-story and a three-story system to simulate the structural behaviour. The resulting systems of second order constant coefficient equations are reformulated as a system of first order ordinary differential equations and solved using the ordinary differential equation solver of MATLAB. Numerical study revealed that pounding behaviour of the buildings has considerable influence on the behaviour of the lighter building causing substantial amplification of the response …
Development And Validation Of Calibration Methods For Discrete Element Modelling, Andrew Grima, Peter W. Wypych
Development And Validation Of Calibration Methods For Discrete Element Modelling, Andrew Grima, Peter W. Wypych
Faculty of Engineering - Papers (Archive)
Discrete element method (DEM) is proving to be a reliable and increasingly used tool to study and predict the behaviour of granular materials. Numerous particlescale mechanisms influence the bulk behaviour and flow of bulk materials. It is important that the relevant measurable input parameters for discrete element models bemeasured by laboratory equipment or determined by physical calibration experiments for rational results. This paper describes some of the bench-scale experiments that have been developed to calibrate the DEM simulations to reflect actual dynamic behaviour. Relevant parameters such as static and rolling coefficients of friction, coefficient of restitution and interparticle cohesion forces …
A Real-Time Measuring Technology For Studying Distortion Of Hydraulic Turbine Blade Castings During Heat Treatment Process, Hailiang Yu, Jinwu Kang, Gang Nie, Haimin Long, Xiaokun Hao, Tianyou Huang
A Real-Time Measuring Technology For Studying Distortion Of Hydraulic Turbine Blade Castings During Heat Treatment Process, Hailiang Yu, Jinwu Kang, Gang Nie, Haimin Long, Xiaokun Hao, Tianyou Huang
Faculty of Engineering - Papers (Archive)
During heat treatment process, the distortion behavior inevitably appears in hydraulic turbine blade castings. In this research, a technology was developed for real-time measurement of the distortion in hydraulic turbine blade castings at the still air cooling and forced air cooling stages during heat treatment process. The method was used to measure the distortion behavior at the cooling stages in both normalizing and tempering processes. At the normalization, the distortion at the blade corner near outlet side undergoes four stages with alternating bending along positive and negative directions. At the tempering stage, the distortion could be divided into two steps. …
Design Of Water Holding Bulkheads For Coal Mines, Verne Mutton, Alexander Remennikov
Design Of Water Holding Bulkheads For Coal Mines, Verne Mutton, Alexander Remennikov
Faculty of Engineering - Papers (Archive)
Water control has been and remains a fundamentally important aspect of underground coal mine design and operation worldwide. Mining in the vicinity of large bodies of water, below a worked out coal seam or under confined aquifer or abandoned water logged workings is always fraught with the possibility of the danger of inundation. Inrush control is now part the Fatal Hazard Protocols which is a risk based process in all operations. In modern Australian underground coal mines, in which panel layouts have been extended and production rates are approaching 10 Mtpa, there is much focus on the control of water …
Graphene V2o5 Nh2o Xerogel Composite Cathodes For Lithium Ion Batteries, Guodong Du, Kuok Hau Seng, Zaiping Guo, Jun Liu, Wenxian Li, D Z. Jia, Christopher D. Cook, Z Liu, Hua-Kun Liu
Graphene V2o5 Nh2o Xerogel Composite Cathodes For Lithium Ion Batteries, Guodong Du, Kuok Hau Seng, Zaiping Guo, Jun Liu, Wenxian Li, D Z. Jia, Christopher D. Cook, Z Liu, Hua-Kun Liu
Faculty of Engineering - Papers (Archive)
A layer structured V2O5·nH2O xerogel was synthesized via a simple green hydrothermal technique by dissolving commercial V2O5 powder in de-ionized water and hydrogen peroxide. Graphene–V2O5·nH2O xerogel composites were then prepared by mixing and filtration of as-prepared V2O5·nH2O xerogel and graphene in the desired ratio. The method is a cost effective and energy saving way to prepare nanostructured composites. Structure and morphology were investigated by X-ray diffraction, thermogravimetric analysis, field emission scanning electron microscopy, …
Review Of Gas Emission Prediction And Control Methods For Multi-Seam Mining In Chinese Coal Mines, Zhongwei Wang, Ting Ren, Lei Zhang
Review Of Gas Emission Prediction And Control Methods For Multi-Seam Mining In Chinese Coal Mines, Zhongwei Wang, Ting Ren, Lei Zhang
Faculty of Engineering - Papers (Archive)
In China, the practice of multi-seam mining with high gas emission rates is common, and many coal mines are suffering from major gas management issues. To deal with these problems, empirical formulas for gas emission prediction and gas control methods suitable for site-specific conditions are developed. Specifically, the statistical method and split–source-method are widely used for gas emission prediction. In addition to ventilation, various gas control methods, including cross-measure boreholes, directional long-holes, dedicated roadways and surface goaf wells are used for gas drainage. Techniques for integrated extraction of coal and coal seam gas have been developed in these coal mines, …
A Decision Support Methodology For Remediation Planning Of Concrete Bridges, Maria Rashidi, Brett P. Lemass
A Decision Support Methodology For Remediation Planning Of Concrete Bridges, Maria Rashidi, Brett P. Lemass
Faculty of Engineering - Papers (Archive)
Bridges are critical and valuable components in any road and rail transportation network. Therefore bridge remediation has always been a top priority for asset managers and engineers, but identifying the nature of true defect deterioration and associated remediation treatments remains a complex task. Nowadays Decision Support Systems (DSS) are widely used to assist decision makers across an extensive spectrum of unstructured decision environments. The main objective of this research is to develop a requirements-driven methodology for bridge monitoring and maintenance which has the ability to assess the bridge condition and find the best remediation treatments using Simple Multi Attribute Rating …
Advanced Directional Drilling Technology For Gas Drainage And Exploration In Australian Coal Mines, Fangtian Wang, Ting Ren, Frank Hungerford, Shihao Tu, Najdat I. Aziz
Advanced Directional Drilling Technology For Gas Drainage And Exploration In Australian Coal Mines, Fangtian Wang, Ting Ren, Frank Hungerford, Shihao Tu, Najdat I. Aziz
Faculty of Engineering - Papers (Archive)
With the continuing technology innovation, directional drilling technology has provided the coal mining industry with effective and practical options for pre- and post-drainage and exploration in Australia. In the past thirty years, in-mine borehole steering equipment has been developed from the single shot camera survey systems to the advanced Directional Drill Monitor utilizing Modular Electrically Connected Cable Assembly (DDM-MECCA) survey instruments, which provides rapid and easy underground borehole survey measurements whilst drilling. The presence of coal seam gas such as methane poses a significant safety hazard to underground coal mining all over the world. However, gas can be captured using …
Development Of A Water-Mist Based Venturi System For Dust Control From Maingate Chocks And Bsl, Ting Ren, Graeme Cooper, Srinivasa Yarlagadda
Development Of A Water-Mist Based Venturi System For Dust Control From Maingate Chocks And Bsl, Ting Ren, Graeme Cooper, Srinivasa Yarlagadda
Faculty of Engineering - Papers (Archive)
Advances in modern longwall (LW) technology have resulted in high production faces with more powerful chocks and shearers that can advance at faster rates. As longwall chocks (supports) advance, crushed roof coal and/or rock can fall from the top of the chock canopy into the face ventilation airflow. Dust survey showed that chock movement is a significant source of dust exposure for shearer operators, accounting for about 47% of total LW face dust make during the cutting cycle. 3D CFD models have been developed to understand the behaviour of longwall dust particles from various sources including maingate (MG) chocks and …
Practice And Prospect Of Fully Mechanised Mininig Technology For Thin Coal Seams Under Complex Conditions In China, Shihao Tu, Fangtian Wang, Yan Lu, Qi Wu, Qingsheng Bai
Practice And Prospect Of Fully Mechanised Mininig Technology For Thin Coal Seams Under Complex Conditions In China, Shihao Tu, Fangtian Wang, Yan Lu, Qi Wu, Qingsheng Bai
Faculty of Engineering - Papers (Archive)
In China, thin coal seam are rich in resources and complex in conditions, however, the characteristics such as narrow mining space, the low level of mechanised technology, bad working environment and the high cost of mining, directly restrict the development of mining safety and high-efficiency. In thin coal seams with hard gangue which contains concretions of pyrite, LS-DYNA is applied to calculate the rational blasting parameters and carry out the deep-hole pre-splitting blasting technology, the hard gangue is fractured effectively, hence advancing the productivity of thin coal seam mining. In addition, the mining rate is sped up in thin protective …
Simultaneous Activated Carbon Adsorption Within A Membrane Bioreactor For An Enhanced Micropollutant Removal, Xueqing Li, Faisal I. Hai, Long Nghiem
Simultaneous Activated Carbon Adsorption Within A Membrane Bioreactor For An Enhanced Micropollutant Removal, Xueqing Li, Faisal I. Hai, Long Nghiem
Faculty of Engineering - Papers (Archive)
Significant adsorption of sulfamethoxazole and carbamazepine to powdered activated carbon (PAC) was confirmed by a series of adsorption tests. In contrast, adsorption of these micropollutants to the sludge was negligible. The removal of these compounds in membrane bioreactor (MBR) was dependent on their hydrophobicity and loading as well as the PAC dosage. Sulfamethoxazole exhibited better removal rate during operation under no or low (0.1 g/L) PAC dosage. When the PAC concentration in MBR was raised to 1.0 g/L, a sustainable and significantly improved performance in the removal of both compounds was observed – the removal efficiencies of sulfamethoxazole and carbamazepine …
Vortex Dynamics For Low- Type-Ii Superconductors, X B Xu, H Fangohr, Z H Wang, M Gu, S.L. Liu, Dongqi Shi, S. X. Dou
Vortex Dynamics For Low- Type-Ii Superconductors, X B Xu, H Fangohr, Z H Wang, M Gu, S.L. Liu, Dongqi Shi, S. X. Dou
Faculty of Engineering - Papers (Archive)
Based on a model appropriate for “marginally type-II” superconducting system, we study the dynamics of vortices with competing interactions by Langevin dynamics simulation. In addition to pinned states and plastic flow, we find that the moving vortex system forms ordered bubble configurations and stripe structures, depending on pinning strength and driving force. The vortex system exhibits a marked hysteresis in its velocity-force characteristic, which results from a dynamical stripe reordering due to intervortex attraction.