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Full-Text Articles in Engineering

The Variable Resonance Magnetorheological Pendulum Tuned Mass Damper: Mathematical Modelling And Seismic Experimental Studies, Matthew Christie, Shuaishuai Sun, Lei Deng, Donghong Ning, Haiping Du, Shiwu Zhang, Weihua Li Jan 2020

The Variable Resonance Magnetorheological Pendulum Tuned Mass Damper: Mathematical Modelling And Seismic Experimental Studies, Matthew Christie, Shuaishuai Sun, Lei Deng, Donghong Ning, Haiping Du, Shiwu Zhang, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part B

Tuned mass damper technologies are progressively advancing through innovative application of smart materials, facilitating more versatile infrastructure protection. During seismic events, primarily encountered surrounding fault lines, highrise buildings and other civil structures can suffer catastrophic failures if not adequately protected. Where traditional passive structural protection may mitigate such damage, adaptive systems which provide controllable vibration attenuation across a wide range of excitation frequencies have seen growth in use, overcoming the challenges resulting from unpredictable seismic spectrums. As a robust solution to this problem, this article presents and analyses a variable resonance magnetorheological-fluid-based pendulum tuned mass damper which employs a rotary ...


Novel Dtn Mobility-Driven Routing In Autonomous Drone Logistics Networks, Saeid Iranmanesh, Raad Raad, Muhammad Salman Raheel, Faisel Em M Tubbal, Tony Jan Jan 2020

Novel Dtn Mobility-Driven Routing In Autonomous Drone Logistics Networks, Saeid Iranmanesh, Raad Raad, Muhammad Salman Raheel, Faisel Em M Tubbal, Tony Jan

Faculty of Engineering and Information Sciences - Papers: Part B

Drones have become prevalent for the delivery of goods by many retail companies such as Amazon and Dominos. Amazon has an issued patent that describes how drones scan and collect data on their fly-overs while dropping off packages. In this context, we propose a path optimization algorithm for a drone multi-hop communications network that can carry and forward data in addition to its primary function of parcel deliveries. We argue that traditional Delay Tolerant Networking (DTN) based protocols may not be efficient for this purpose. Therefore, this paper proposes a new DTN-based algorithm that optimizes drone flight paths in conjunction ...


Performance Of Ballast Influenced By Deformation And Degradation: Laboratory Testing And Numerical Modeling, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn Jan 2020

Performance Of Ballast Influenced By Deformation And Degradation: Laboratory Testing And Numerical Modeling, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents a study on the deformation and degradation responses of railway ballast using large-scale laboratory testing and computational modeling approaches. A series of large-scale triaxial tests were carried out to investigate the ballast breakage responses under cyclic train loading subjected to varying frequencies, f=10-40  Hz. The role of recycled rubber energy-absorbing mats (REAMs) on reducing ballast breakage was also examined. Laboratory test results show that the ballast experiences significant degradation (breakage) and deformation, while the inclusion of REAMs can reduce the ballast breakage up to about 35%. Numerical modeling using the coupled discrete-continuum approach [coupled discrete-element method-finite-difference ...


Research On Fault Detection For Three Types Of Wind Turbine Subsystems Using Machine Learning, Zuojun Liu, Cheng Xiao, Tieling Zhang, Xu Zhang Jan 2020

Research On Fault Detection For Three Types Of Wind Turbine Subsystems Using Machine Learning, Zuojun Liu, Cheng Xiao, Tieling Zhang, Xu Zhang

Faculty of Engineering and Information Sciences - Papers: Part B

2020 by the authors. In wind power generation, one aim of wind turbine control is to maintain it in a safe operational status while achieving cost-effective operation. The purpose of this paper is to investigate new techniques for wind turbine fault detection based on supervisory control and data acquisition (SCADA) system data in order to avoid unscheduled shutdowns. The proposed method starts with analyzing and determining the fault indicators corresponding to a failure mode. Three main system failures including generator failure, converter failure and pitch system failure are studied. First, the indicators data corresponding to each of the three key ...


Beam-Based Analog Self-Interference Cancellation In Full-Duplex Mimo Systems, Anh Tuyen Le, Le Chung Tran, Xiaojing Huang, Y. Jay Guo Jan 2020

Beam-Based Analog Self-Interference Cancellation In Full-Duplex Mimo Systems, Anh Tuyen Le, Le Chung Tran, Xiaojing Huang, Y. Jay Guo

Faculty of Engineering and Information Sciences - Papers: Part B

Self-interference (SI) cancellation for full-duplex (FD) multiple input multiple output (MIMO) systems is challenging due to both hardware and signal processing complexity. In this paper, a beam-based adaptive filter structure with analog least mean square (ALMS) loops is proposed to significantly reduce the complexity of SI cancellation for FD MIMO systems. With this structure, the number of adaptive filters required for SI cancellation scales linearly with the number of transmit beams rather than quadratically with the number of antennas. Furthermore, to avoid additional transmit chains used to upconvert the beam signals to generate reference signals for the ALMS loops, a ...


Air Void Detection Using Variational Mode Decomposition With Low Rank, Fok Hing Chi Tivive, Abdesselam Bouzerdoum, Shivakumar Karekal Jan 2020

Air Void Detection Using Variational Mode Decomposition With Low Rank, Fok Hing Chi Tivive, Abdesselam Bouzerdoum, Shivakumar Karekal

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents an air-void detection technique for air-coupled radar, which emits electromagnetic waves to interrogate an air-void inside a medium or between two media. The reflections from the air-medium interfaces are usually corrupted by air-coupling, antenna ringing, and internal reflections, rendering air-void detection very difficult or, in certain cases, impossible. The proposed method exploits the low-rank structure of the background clutter to suppress these nuisance signals. A variational mode decomposition model is developed to extract the backscattering at different air-medium interfaces as signal modes. Real experiments are conducted using a stepped frequency radar. The experimental results show that the ...


Attention-Based Residual Network With Scattering Transform Features For Hyperspectral Unmixing With Limited Training Samples, Yiliang Zeng, Christian H. Ritz, Jiahong Zhao, Jinhui Lan Jan 2020

Attention-Based Residual Network With Scattering Transform Features For Hyperspectral Unmixing With Limited Training Samples, Yiliang Zeng, Christian H. Ritz, Jiahong Zhao, Jinhui Lan

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 by the authors. This paper proposes a framework for unmixing of hyperspectral data that is based on utilizing the scattering transform to extract deep features that are then used within a neural network. Previous research has shown that using the scattering transform combined with a traditional K-nearest neighbors classifier (STFHU) is able to achieve more accurate unmixing results compared to a convolutional neural network (CNN) applied directly to the hyperspectral images. This paper further explores hyperspectral unmixing in limited training data scenarios, which are likely to occur in practical applications where the access to large amounts of labeled training ...


On The Energy Efficiency Of Massive Mimo Systems With Low-Resolution Adcs And Lattice Reduction Aided Detectors, Zhitao Xiao, Jincan Zhao, Tianle Liu, Lei Geng, Fang Zhang, Jun Tong Jan 2020

On The Energy Efficiency Of Massive Mimo Systems With Low-Resolution Adcs And Lattice Reduction Aided Detectors, Zhitao Xiao, Jincan Zhao, Tianle Liu, Lei Geng, Fang Zhang, Jun Tong

Faculty of Engineering and Information Sciences - Papers: Part B

As an effective technology for boosting the performance of wireless communications, massive multiple-input multiple-output (MIMO) systems based on symmetric antenna arrays have been extensively studied. Using low-resolution analog-to-digital converters (ADCs) at the receiver can greatly reduce hardware costs and circuit complexity to further improve the energy efficiency (EE) of the system. There are significant research on the design of MIMO detectors but there is limited study on their performance in terms of EE. This paper studies the effect of signal detection on the EE in practical systems, and proposes to apply several signal detectors based on lattice reduction successive interference ...


Attribute-Based Equality Test Over Encrypted Data Without Random Oracles, Yuanhao Wang, Yuzhao Cui, Qiong Huang, Hongbo Li, Jianye Huang, Guomin Yang Jan 2020

Attribute-Based Equality Test Over Encrypted Data Without Random Oracles, Yuanhao Wang, Yuzhao Cui, Qiong Huang, Hongbo Li, Jianye Huang, Guomin Yang

Faculty of Engineering and Information Sciences - Papers: Part B

© 2013 IEEE. Sensitive data would be encrypted before uploading to the cloud due to the privacy issue. However, how to compare the encrypted data efficiently becomes a problem. Public Key Encryption with Equality Test (PKEET) provides an efficient way to check whether two ciphertexts (of possibly different users) contain the same message without decryption. As an enhanced variant, Attribute-based Encryption with Equality Test (ABEET) provides a flexible mechanism of authorization on the equality test. Most of the existing ABEET schemes are only proved to be secure in the random oracle model. Their security, however, would not be guaranteed if random ...


The Contribution Of Electronic Health Records To Risk Management Through Accreditation Of Residential Aged Care Homes In Australia, Ping Yu, Tao Jiang, David M. Hailey, Jun Ma, Siyu Qian Jan 2020

The Contribution Of Electronic Health Records To Risk Management Through Accreditation Of Residential Aged Care Homes In Australia, Ping Yu, Tao Jiang, David M. Hailey, Jun Ma, Siyu Qian

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 The Author(s). Background: The Australian government has implemented a compulsory aged care accreditation system to guide and monitor the risk management approach in registered residential aged care (RAC) homes. This research assessed the contribution of electronic health records (EHR) to risk management in RAC homes in relation to the extent that aged care accreditation fulfils its role. Methods: A convenience sample of 5560 aged care accreditation reports published from 2011 to 2018 was manually downloaded from the Accreditation Agency web site. A mixed-method approach of text data mining and manual content analysis was used to identify any significant ...


Mechanistic-Empirical Permanent Deformation Models: Laboratory Testing, Modelling And Ranking, Ana Ramos, Antonio Gomes, Buddhima Indraratna, Ngoc Trung Ngo, Rui Calcada, Pedro Costa Jan 2020

Mechanistic-Empirical Permanent Deformation Models: Laboratory Testing, Modelling And Ranking, Ana Ramos, Antonio Gomes, Buddhima Indraratna, Ngoc Trung Ngo, Rui Calcada, Pedro Costa

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 Elsevier Ltd Geomaterials exhibit elastoplastic behaviour during dynamic and repeated loading conditions. These loads are induced by the passage of a train or vehicle which then generates recoverable (resilient) deformation and/or permanent (plastic) deformation. Modelling this behaviour is still a challenge for geotechnical engineers as it implies the understanding of the complex deformation mechanism and application of advanced constitutive models. This paper reviews on the major causes of permanent deformation and the factors that influence the long-term performance of materials. It will also present the fundamental concepts of permanent deformation as well as the models and approaches used ...


Advancement Of Rail Ballast Testing Methodologies And Design Implications, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Fernanda Ferreira Jan 2020

Advancement Of Rail Ballast Testing Methodologies And Design Implications, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Fernanda Ferreira

Faculty of Engineering and Information Sciences - Papers: Part B

Given the limited capacity of available railway tracks in Australia to sustain increasingly faster and heavier trains, the development of innovative and sustainable ballasted tracks is essential for Australian transport infrastructure. Upon repeated train loading, ballast aggregates become degraded and fouled owing to the intrusion of external fines either from the subbase or surface, which decreases track drainage potentially leading to track instability. This paper reviews some advancements in testing methodologies and design implications of ballasted tracks stabilized with artificial inclusions, including geocomposites, energy absorbing rubber mats and end-of-life tires. Measured test data shows that the use of these waste ...


Tunable Strong Photo-Mixing In Weyl Semimetals, Jack Zuber, T Zhao, S Gong, M Hu, R Zhong, C Zhang, S Liu Jan 2020

Tunable Strong Photo-Mixing In Weyl Semimetals, Jack Zuber, T Zhao, S Gong, M Hu, R Zhong, C Zhang, S Liu

Faculty of Engineering and Information Sciences - Papers: Part B

We study both the temperature and band-gap dependence of the first-and third-order intraband conductivities of a Weyl semimetal (WSM) as well as the resultant critical field. By a semiclassical model we further explore how different chemical potentials, cone separations, field geometries, and finite relaxation times affect photoresponse. We determine that the band-gap variation is characterized by the Weyl cone separation and observe significant thermal enhancement of the nonlinear response. Universal behaviors of both the linear and nonlinear response have also been observed under certain conditions. Coupled with experimentally accessible critical field values of 104-105 V m-1, our results give strong ...


A Noise Study Of The Psw Signature Family: Patching Drs With Uniform Distribution, Arnaud Sipasseuth, Thomas Plantard, Willy Susilo Jan 2020

A Noise Study Of The Psw Signature Family: Patching Drs With Uniform Distribution, Arnaud Sipasseuth, Thomas Plantard, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part B

At PKC 2008, Plantard et al. published a theoretical framework for a lattice-based signature scheme, namely Plantard-Susilo-Win (PSW). Recently, after ten years, a new signature scheme dubbed the Diagonal Reduction Signature (DRS) scheme was presented in the National Institute of Standards and Technology (NIST) PQC Standardization as a concrete instantiation of the initial work. Unfortunately, the initial submission was challenged by Yu and Ducas using the structure that is present on the secret key noise. In this paper, we are proposing a new method to generate random noise in the DRS scheme to eliminate the aforementioned attack, and all subsequent ...


Influence Of O2 On The Erosion-Corrosion Performance Of 3cr Steels In Co2 Containing Environment, Lei Xia, Yan Li, Leilei Ma, Hongmei Zhang, Nan Li, Zhengyi Jiang Jan 2020

Influence Of O2 On The Erosion-Corrosion Performance Of 3cr Steels In Co2 Containing Environment, Lei Xia, Yan Li, Leilei Ma, Hongmei Zhang, Nan Li, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part B

2020 by the authors. With the introduction of O2 during oil and gas production, the erosion-corrosion rate of tubing steels increases; the objective of this report is to explore the reason for this. Erosion-corrosion experiments were performed in environments of CO2 and CO2-O2, respectively. Macrographs, microstructures, and the compositions of erosion-corrosion scales were investigated using a digital camera, scanning electron microscope (SEM), Kevex-SuperDry energy spectrometer (EDS) and Xray diffraction (XRD). The results show that the erosion-corrosion products are composed of large FeCO3 particles and some amorphous product in the CO2 environment, while they are made up of FeCO3, Fe2O3, Fe3O4 ...


Sparsity-Based Robust Bistatic Mimo Radar Imaging In The Presence Of Array Errors, Wenyu Gao, Jun Li, Daming Zhang, Qinghua Guo Jan 2020

Sparsity-Based Robust Bistatic Mimo Radar Imaging In The Presence Of Array Errors, Wenyu Gao, Jun Li, Daming Zhang, Qinghua Guo

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 Wenyu Gao et al. A sparse recovery method for robust transmit-receive angle imaging in a bistatic MIMO radar is proposed to deal with the effect of array gain-phase errors. The impact of multiplicative array gain-phase errors is changed to be additive through model reformulation, and transmit-receive angle imaging is formulated to a sparse total least square signal problem. Then, an iterative algorithm is proposed to solve the optimization problem. Compared with existing methods, the proposed method can achieve a significant performance gain in the case that the number of snapshots is small. Simulation results verify the effectiveness of the ...


A Judicious Decision-Making Approach For Power Dispatch In Smart Grid Using A Multiobjective Evolutionary Algorithm Based On Decomposition, Chixin Xiao, Danny Sutanto, Kashem M. Muttaqi, Minjie Zhang Jan 2020

A Judicious Decision-Making Approach For Power Dispatch In Smart Grid Using A Multiobjective Evolutionary Algorithm Based On Decomposition, Chixin Xiao, Danny Sutanto, Kashem M. Muttaqi, Minjie Zhang

Faculty of Engineering and Information Sciences - Papers: Part B

© 1972-2012 IEEE. Multiobjective evolutionary algorithm based on decomposition (MOEA/D) is an efficient mathematical strategy for solving multiobjective optimization problems. However, the MOEA/D algorithm has not yet been widely used on the multiobjective optimal power flow (MOPF) problems, which consider several conflicting objectives with varying tradeoff levels. This article proposes a novel differential evolution (DE) strategy based on the MOEA/D framework to quickly determine a set of optimal solutions of MOPFs, in the objective space formed from the different objectives, such as the most optimal economic dispatch, the least environmental emission objectives, and the minimum transmission losses, while ...


An Integrated Energy Management Approach For The Economic Operation Of Industrial Microgrids Under Uncertainty Of Renewable Energy, Ghulam Mohy-Ud-Din, Dao Hoang Vu, Kashem M. Muttaqi, Danny Sutanto Jan 2020

An Integrated Energy Management Approach For The Economic Operation Of Industrial Microgrids Under Uncertainty Of Renewable Energy, Ghulam Mohy-Ud-Din, Dao Hoang Vu, Kashem M. Muttaqi, Danny Sutanto

Faculty of Engineering and Information Sciences - Papers: Part B

© 1972-2012 IEEE. Many modern industries are equipped with onsite renewable generation and are normally connected to the grid. A battery energy storage system (BESS) can complement the intermittency of the available onsite renewable generation. The combination of the BESS and the renewable generation can operate as a microgrid. If the microgrid is properly sized and managed, it is possible to reduce the electricity bill to have a huge saving in the electricity cost. This article proposes an energy management system for such an industrial microgrids. The decisions to charge and discharge the BESS in the proposed energy management are usually ...


From Ideal To Reality: Segmentation, Annotation, And Recommendation, The Vital Trajectory Of Intelligent Micro Learning, Jiayin Lin, Geng Sun, Tingru Cui, Jun Shen, Dongming Xu, Ghassan Beydoun, Ping Yu, David Pritchard, Li Li, Shiping Chen Jan 2020

From Ideal To Reality: Segmentation, Annotation, And Recommendation, The Vital Trajectory Of Intelligent Micro Learning, Jiayin Lin, Geng Sun, Tingru Cui, Jun Shen, Dongming Xu, Ghassan Beydoun, Ping Yu, David Pritchard, Li Li, Shiping Chen

Faculty of Engineering and Information Sciences - Papers: Part B

The soaring development of Web technologies and mobile devices has blurred time-space boundaries of people’s daily activities. Such development together with the life-long learning requirement give birth to a new learning style, micro learning. Micro learning aims to effectively utilize learners’ fragmented time to carry out personalized learning activities through online education resources. The whole workflow of a micro learning system can be separated into three processing stages: micro learning material generation, learning materials annotation and personalized learning materials delivery. Our micro learning framework is firstly introduced in this paper from a higher perspective. Then we will review representative ...


Combined General Vector Machine For Single Point Electricity Load Forecast, Binbin Yong, Yongqiang Wei, Jun Shen, Fucun Li, Xuetao Jiang, Qingguo Zhou Jan 2020

Combined General Vector Machine For Single Point Electricity Load Forecast, Binbin Yong, Yongqiang Wei, Jun Shen, Fucun Li, Xuetao Jiang, Qingguo Zhou

Faculty of Engineering and Information Sciences - Papers: Part B

General Vector Machine (GVM) is a newly proposed machine learning model, which is applicable to small samples forecast scenarios. In this paper, the GYM is applied into electricity load fore­cast based on single point modeling method. Meanwhile, traditional time series forecast models, including back propagation neural network (BPNN), Support Vector Machine (SVM) and Autoregressive Integrated Moving Average Model ( ARIMA), are also experimented for single point electricity load forecast. Further, the combined model based on GYM, BPNN, SVM and ARIMA are proposed and verified. Results show that GYM performs better than these traditional models, and the combined model outperforms any ...


Design And Optimization Of A Novel Dual-Port Linear Generator For Oceanic Wave Energy Conversion, Omar Farrok, Md Rabiul Islam, Kashem M. Muttaqi, Danny Sutanto, Jianguo Zhu Jan 2020

Design And Optimization Of A Novel Dual-Port Linear Generator For Oceanic Wave Energy Conversion, Omar Farrok, Md Rabiul Islam, Kashem M. Muttaqi, Danny Sutanto, Jianguo Zhu

Faculty of Engineering and Information Sciences - Papers: Part B

All the existing linear generators used for oceanic wave energy conversions are basically a single-port linear electrical generators (SPLEGs). The conventional SPLEG transfers electrical power to the load/grid discontinuously due to its working principle and the intermittent nature of oceanic waves. This paper proposes a new dual-port linear electrical generator (DPLEG) topology, which is capable to transfer electrical power with an adequate voltage even at zero vertical velocity of the oceanic wave. The analysis shows that the efficiency and the performance of the DPLEG depend greatly on the stator tooth design. For this reason, the proposed DPLEG is optimized ...


Dtn And Non-Dtn Routing Protocols For Inter-Cubesat Communications: A Comprehensive Survey, Mohamed Atef Madni, Saeid Iranmanesh, Raad Raad Jan 2020

Dtn And Non-Dtn Routing Protocols For Inter-Cubesat Communications: A Comprehensive Survey, Mohamed Atef Madni, Saeid Iranmanesh, Raad Raad

Faculty of Engineering and Information Sciences - Papers: Part B

CubeSats, which are limited by size and mass, have limited functionality. These miniaturised satellites suffer from a low power budget, short radio range, low transmission speeds, and limited data storage capacity. Regardless of these limitations, CubeSats have been deployed to carry out many research missions, such as gravity mapping and the tracking of forest fires. One method of increasing their functionality and reducing their limitations is to form CubeSat networks, or swarms, where many CubeSats work together to carry out a mission. Nevertheless, the network might have intermittent connectivity and, accordingly, data communication becomes challenging in such a disjointed network ...


Upright Radiation Therapy—A Historical Reflection And Opportunities For Future Applications, Sulman Rahim, James Korte, Nicholas G. Hardcastle, Sarah Hegarty, Tomas Kron, Sarah Everitt Jan 2020

Upright Radiation Therapy—A Historical Reflection And Opportunities For Future Applications, Sulman Rahim, James Korte, Nicholas G. Hardcastle, Sarah Hegarty, Tomas Kron, Sarah Everitt

Faculty of Engineering and Information Sciences - Papers: Part B

Since the early days of megavoltage Radiation Therapy (RT), the potential of delivering treatment to a sub group of patients in an upright position has been recognized. Compared to lying horizontally, treating patients in an upright position offers potential benefits in terms of patient comfort especially for patients experiencing dyspnoea and saliva accumulation when lying down. Dosimetric benefits can also be gained from changes in the volume and location of lungs and heart in an upright position, which are potentially advantageous for clinical situations including Hodgkin's disease, lung and breast malignancies. Since the 1950's, upright stabilization mechanisms have ...


Barriers And Facilitators That Influence Telemedicine-Based, Real-Time, Online Consultation At Patients' Homes: Systematic Literature Review, Hassan Almathami, Khin Than Win, Elena Vlahu-Gjorgievska Jan 2020

Barriers And Facilitators That Influence Telemedicine-Based, Real-Time, Online Consultation At Patients' Homes: Systematic Literature Review, Hassan Almathami, Khin Than Win, Elena Vlahu-Gjorgievska

Faculty of Engineering and Information Sciences - Papers: Part B

©Hassan Khader Y Almathami, Khin Than Win, Elena Vlahu-Gjorgievska. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 20.02.2020. BACKGROUND: Health care providers are adopting information and communication technologies (ICTs) to enhance their services. Telemedicine is one of the services that rely heavily on ICTs to enable remote patients to communicate with health care professionals; in this case, the patient communicates with the health care professional for a follow-up or for a consultation about his or her health condition. This communication process is referred to as an e-consultation. In this paper, telemedicine services refer ...


Effect Of Rock Brittleness On Propagation Of Hydraulic Fractures In Shale Reservoirs With Bedding-Planes, Zhaohui Chong, Qiangling Yao, Xuehua Li, Liu Zhu, Chuanjin Tang Jan 2020

Effect Of Rock Brittleness On Propagation Of Hydraulic Fractures In Shale Reservoirs With Bedding-Planes, Zhaohui Chong, Qiangling Yao, Xuehua Li, Liu Zhu, Chuanjin Tang

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 The Authors. Energy Science & Engineering published by the Society of Chemical Industry and John Wiley & Sons Ltd. Hydraulic fracturing forms complex hydraulic fracture networks (HFNs) in shale reservoirs and significantly improves the permeability of shale reservoirs. Although rock brittleness is a major factor in determining whether a shale reservoir can be fractured, the relationship between HFNs and rock brittleness remains unclear. To investigate this relationship in a shale reservoir with bedding planes, this paper presents a series of hydraulic fracturing simulations based on a hydromechanically coupled discrete element model. In addition, we analyzed the sensitivity of the difference in ...


Biogeochemical Clogging Of Permeable Reactive Barriers In Acid-Sulfate Soil Floodplain, Buddhima Indraratna, Subhani Medawela, R Rowe, Ngamta Thamwattana, Ana Heitor Jan 2020

Biogeochemical Clogging Of Permeable Reactive Barriers In Acid-Sulfate Soil Floodplain, Buddhima Indraratna, Subhani Medawela, R Rowe, Ngamta Thamwattana, Ana Heitor

Faculty of Engineering and Information Sciences - Papers: Part B

© 2020 American Society of Civil Engineers. Column experiments that investigate the use of calcitic limestone as a potential material for permeable reactive barriers (PRBs), as well as its clogging behavior, are conducted under conditions that involve continuous acidic flow containing Al, Fe, and acidophilic bacteria. Results show that nonhomogenous biogeochemical clogging occurred toward the outlet, resulting in a 45% reduction of hydraulic conductivity at the inlet and 10% reduction at the outlet after the bicarbonate buffering period. A mathematical model developed to capture the reductions in longevity is presented. The model, which considers the effects of time-varying porosity, hydraulic conductivity ...


Approaches To Dealing With Missing Data In Railway Asset Management, Paul Mcmahon, Tieling Zhang, Richard Dwight Jan 2020

Approaches To Dealing With Missing Data In Railway Asset Management, Paul Mcmahon, Tieling Zhang, Richard Dwight

Faculty of Engineering and Information Sciences - Papers: Part B

The collection of reliable and high-quality data is seen as a prerequisite for effective and efficient rail infrastructure and rolling stock asset management to meet the requirements of asset owners and service providers. In this paper, the importance of recovering missing information in railway asset management is highlighted, and the advanced models and algorithms that have been applied to recovering the missed data are analyzed and discussed. Through making comparisons among these models and algorithms, a procedure is proposed to guide selecting the appropriate models based on different data missing scenarios. Using the newly developed framework with one dataset from ...


Deep Gabor Neural Network For Automatic Detection Of Mine-Like Objects In Sonar Imagery, Hoang Thanh Le, Son Lam Phung, Philip B. Chapple, Abdesselam Bouzerdoum, Christian H. Ritz, Le Chung Tran Jan 2020

Deep Gabor Neural Network For Automatic Detection Of Mine-Like Objects In Sonar Imagery, Hoang Thanh Le, Son Lam Phung, Philip B. Chapple, Abdesselam Bouzerdoum, Christian H. Ritz, Le Chung Tran

Faculty of Engineering and Information Sciences - Papers: Part B

With the advances in sonar imaging technology, sonar imagery has increasingly been used for oceanographic studies in civilian and military applications. High-resolution imaging sonars can be mounted on various survey platforms, typically autonomous underwater vehicles, which provide enhanced speed and improved data quality with long-range support. This paper addresses the automatic detection of mine-like objects using sonar images. The proposed Gabor-based detector is designed as a feature pyramid network with a small number of trainable weights. Our approach combines both semantically weak and strong features to handle mine-like objects at multiple scales effectively. For feature extraction, we introduce a parameterized ...


Capacity Maximized Linear Precoder Design For Spatial-Multiplexing Mimo Vlc Systems, Yanrong Zhai, Hao Chi, Jun Tong, Jiangtao Xi Jan 2020

Capacity Maximized Linear Precoder Design For Spatial-Multiplexing Mimo Vlc Systems, Yanrong Zhai, Hao Chi, Jun Tong, Jiangtao Xi

Faculty of Engineering and Information Sciences - Papers: Part B

© 2013 IEEE. This paper proposes a novel linear precoder design based on the singular value decomposition (SVD) for multi-input multi-output visible light communications (MIMO VLC). We provide an analytical expression on power allocation subject to the function of maximizing the lower bound of capacity according to the optical wireless communication channel model. The expression is rather different from the radio frequency (RF) communications due to the non-negativity of the transmitted signals in VLC. Furthermore, we design an adaptive bit loading scheme for sub-streams with consideration of the tremendous gain difference among subchannels. Performances of the proposed adaptive power and bits ...


Negative Sequence Voltage Compensating For Unbalanced Standalone Brushless Doubly-Fed Induction Generator, Wei Xu, Omer Mohammed Elbabo Mohammed, Yi Liu, Md Rabiul Islam Jan 2020

Negative Sequence Voltage Compensating For Unbalanced Standalone Brushless Doubly-Fed Induction Generator, Wei Xu, Omer Mohammed Elbabo Mohammed, Yi Liu, Md Rabiul Islam

Faculty of Engineering and Information Sciences - Papers: Part B

During the unbalance operation of a standalone brushless doubly-fed induction generator (BDFIG), the negative sequence component causes significant unbalanced effect on the voltage and current of the power winding (PW). In this paper, anew control strategy is proposed to minimize the voltage unbalance effect of a standalone BDFIG under unbalanced loads. The proposed control strategy consists of two parts. The first part represents the conventional direct voltage control (DVC) strategy to control the frequency and magnitude of the positivesequence PW voltage. The second part is the proposed strategy to minimize the negative sequence component in the output voltage of PW ...