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A Hybrid Unsupervised Clustering-Based Anomaly Detection Method, Guo Pu, Lijuan Wang, Jun Shen, Fang Dong Jan 2021

A Hybrid Unsupervised Clustering-Based Anomaly Detection Method, Guo Pu, Lijuan Wang, Jun Shen, Fang Dong

Faculty of Engineering and Information Sciences - Papers: Part B

In recent years, machine learning-based cyber intrusion detection methods have gained increasing popularity. The number and complexity of new attacks continue to rise; therefore, effective and intelligent solutions are necessary. Unsupervised machine learning techniques are particularly appealing to intrusion detection systems since they can detect known and unknown types of attacks as well as zero-day attacks. In the current paper, we present an unsupervised anomaly detection method, which combines Sub-Space Clustering (SSC) and One Class Support Vector Machine (OCSVM) to detect attacks without any prior knowledge. The proposed approach is evaluated using the well-known NSL-KDD dataset. The experimental results demonstrate …


An Edge Based Multi-Agent Auto Communication Method For Traffic Light Control, Qiang Wu, Jianqing Wu, Jun Shen, Binbin Yong, Qingguo Zhou Jan 2020

An Edge Based Multi-Agent Auto Communication Method For Traffic Light Control, Qiang Wu, Jianqing Wu, Jun Shen, Binbin Yong, Qingguo Zhou

Faculty of Engineering and Information Sciences - Papers: Part B

With smart city infrastructures growing, the Internet of Things (IoT) has been widely used in the intelligent transportation systems (ITS). The traditional adaptive traffic signal control method based on reinforcement learning (RL) has expanded from one intersection to multiple intersections. In this paper, we propose a multi-agent auto communication (MAAC) algorithm, which is an innovative adaptive global traffic light control method based on multi-agent reinforcement learning (MARL) and an auto communication protocol in edge computing architecture. The MAAC algorithm combines multi-agent auto communication protocol with MARL, allowing an agent to communicate the learned strategies with others for achieving global optimization …


Ensemble Neural Network Method For Wind Speed Forecasting, Binbin Yong, Fei Qiao, Chen Wang, Jun Shen, Yongqiang Wei, Qingguo Zhou Jan 2019

Ensemble Neural Network Method For Wind Speed Forecasting, Binbin Yong, Fei Qiao, Chen Wang, Jun Shen, Yongqiang Wei, Qingguo Zhou

Faculty of Engineering and Information Sciences - Papers: Part B

Wind power generation has gradually developed into an important approach of energy supply. Meanwhile, due to the difficulty of electricity storage, wind power is greatly affected by the real-time wind speed in wind fields. Generally, wind speed has the characteristics of nonlinear, irregular, and non-stationary, which make accurate wind speed forecasting a difficult problem. Recent studies have shown that ensemble forecasting approaches combining different sub-models is an efficient way to solve the problem. Therefore, in this article, two single models are ensembled for wind speed forecasting. Meanwhile, four data pre-processing hybrid models are combined with the reliability weights. The proposed …


A Method Of Uncertainty Analysis For Whole-Life Embodied Carbon Emissions (Co2-E) Of Building Materials Of A Net-Zero Energy Building In Australia, Mehdi Robati, Daniel J. Daly, Georgios Kokogiannakis Jan 2019

A Method Of Uncertainty Analysis For Whole-Life Embodied Carbon Emissions (Co2-E) Of Building Materials Of A Net-Zero Energy Building In Australia, Mehdi Robati, Daniel J. Daly, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part B

The construction of new buildings requires the use of a substantial amount of materials, which have an associated embodied energy for manufacturing, transport, construction and end-of-life disposal. A number of inventories have been developed to collate the typical embodied energy or carbon emissions associated with different building materials and activities, and these can be used to quantify the environmental impacts of different construction methods. However, uncertainty exists in the estimation of embodied CO2-e emissions and other environmental impact results, due to i) inconsistencies in typical embodied carbon emissions values in inventories; ii) errors in estimations of material quantities; iii) assumptions …


Human Action Segmentation Based On A Streaming Uniform Entropy Slice Method, Cheng Peng, Sio-Long Lo, Jie Huang, Ah Chung Tsoi Jan 2018

Human Action Segmentation Based On A Streaming Uniform Entropy Slice Method, Cheng Peng, Sio-Long Lo, Jie Huang, Ah Chung Tsoi

Faculty of Engineering and Information Sciences - Papers: Part B

Segmentation of human actions is a major research problem in video understanding. A number of existing approaches demonstrate that performing action segmentation before action recognition results in better recognition performance. In this paper, we address the problem of action segmentation in an online manner. We first extend the clustering-based image segmentation approach into a temporal one, where hierarchical supervoxel levels for action segmentation are generated accordingly. We then propose a streaming approach to flatten the hierarchical levels into one based on Uniform Entropy Slice (UES), in order to preserve important information in the video. The flattened level contains the silhouette …


Design Of Geopolymer Concrete With Ggbfs At Ambient Curing Condition Using Taguchi Method, Muhammad N. S Hadi, Nabeel Farhan, M Neaz Sheikh Jan 2017

Design Of Geopolymer Concrete With Ggbfs At Ambient Curing Condition Using Taguchi Method, Muhammad N. S Hadi, Nabeel Farhan, M Neaz Sheikh

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, the Taguchi method has been used to design optimum mix proportions for geopolymer concrete with ground granulated blast furnace slag (GGBFS) as aluminosilicate source at ambient curing condition. The influences of binder content, alkaline activator to binder content (Al/Bi) ratio, sodium silicate to sodium hydroxide (SS/SH) ratio, and sodium hydroxide (SH) concentration on the geopolymer concrete were investigated. A total of nine mix designs were evaluated. It was found that specimens with a binder content of 450 kg/m3, Al/Bi ratio of 0.35, SS/SH ratio of 2.5, and SH concentration of 14 M produced the highest …


Integrated Condition Monitoring And Prognosis Method For Incipient Defect Detection And Remaining Life Prediction Of Low Speed Slew Bearings, Wahyu Caesarendra, Tegoeh Tjahjowidodo, Buyung Kosasih, Anh Kiet Tieu Jan 2017

Integrated Condition Monitoring And Prognosis Method For Incipient Defect Detection And Remaining Life Prediction Of Low Speed Slew Bearings, Wahyu Caesarendra, Tegoeh Tjahjowidodo, Buyung Kosasih, Anh Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents an application of multivariate state estimation technique (MSET), sequential probability ratio test (SPRT) and kernel regression for low speed slew bearing condition monitoring and prognosis. The method is applied in two steps. Step (1) is the detection of the incipient slew bearing defect. In this step, combined MSET and SPRT is used with circular-domain kurtosis, time-domain kurtosis, wavelet decomposition (WD) kurtosis, empirical mode decomposition (EMD) kurtosis and the largest Lyapunov exponent (LLE) feature. Step (2) is the prediction of the selected features' trends and the estimation of the remaining useful life (RUL) of the slew bearing. In …


Simulation Of The Melting Process Of Ice Slurry For Energy Storage Using A Two-Fluid Lattice Boltzmann Method, Qi Lin, Shugang Wang, Zhenjun Ma, Jihong Wang, Tengfei Zhang Jan 2017

Simulation Of The Melting Process Of Ice Slurry For Energy Storage Using A Two-Fluid Lattice Boltzmann Method, Qi Lin, Shugang Wang, Zhenjun Ma, Jihong Wang, Tengfei Zhang

Faculty of Engineering and Information Sciences - Papers: Part B

Ice slurry can be used as the thermal storage media in latent cool storage systems for both residential and commercial buildings. This paper presents the investigation of the phase change characteristics of the ice slurry using a two-fluid Lattice Boltzmann Method (TFLBM). The melting and migration processes of the ice slurry are simulated by improving the equilibrium distribution function and matching the relevant parameters such as the kinetic viscosity of ice particle cluster and cross-collision coefficient. The sensitivity analysis of the ice slurry viscosity and cross-collision coefficient are achieved through six numerical experiments, and the ice melting in the internal-melt …


Thermal Performance Evaluation Of An Integrated Photovoltaic Thermal-Phase Change Material System Using Taguchi Method, Haoshan Ren, Wenye Lin, Zhenjun Ma, Wenke Fan Jan 2017

Thermal Performance Evaluation Of An Integrated Photovoltaic Thermal-Phase Change Material System Using Taguchi Method, Haoshan Ren, Wenye Lin, Zhenjun Ma, Wenke Fan

Faculty of Engineering and Information Sciences - Papers: Part B

This paper presents the performance evaluation of an integrated photovoltaic thermal (PVT) collector-phased change material (PCM) thermal energy storage (TES) system. The PVT collectors can generate both electricity and low-grade thermal energy during the daytime, and the thermal energy generated can be temporarily stored in the PCM TES unit and used for space heating during the night-time. Taguchi method and analysis of variance are used for the simulation design and data analysis, respectively. The thermal performance of the proposed system was evaluated in terms of the useful energy stored in the TES system. The results showed that the outlet air …


Modeling Behaviour Of Railway Ballast In Prismoidal Apparatus Using Discrete Element Method, Gino O. Calderon Vizcarra, Sanjay Nimbalkar, Michele Dal Toe Casagrande Jan 2016

Modeling Behaviour Of Railway Ballast In Prismoidal Apparatus Using Discrete Element Method, Gino O. Calderon Vizcarra, Sanjay Nimbalkar, Michele Dal Toe Casagrande

Faculty of Engineering and Information Sciences - Papers: Part A

This article presents the results of numerical simulations of loading tests conducted on coarse particles that simulate railroad ballast. The objective of this study was to evaluate the deformation of ballast under vertical loading and to study the influence of the two different particle size distributions. One of them was according to particle size distribution recommended by Indraratna and co-workers in the past as an improvement to Australian Standard and the other was prepared in accordance with Brazilian standard. The discrete element method offers a new means of studying the response characteristics of railway ballast. The basic idea of discrete …


An Elasto-Plastic Method For Analysing The Deformation Of The Railway Ballast, Qideng Sun, Buddhima Indraratna, Sanjay Nimbalkar Jan 2016

An Elasto-Plastic Method For Analysing The Deformation Of The Railway Ballast, Qideng Sun, Buddhima Indraratna, Sanjay Nimbalkar

Faculty of Engineering and Information Sciences - Papers: Part A

In this study, a series of monotonically drained triaxial tests were conducted using the large-scale cylindrical triaxial apparatus. The effect of particle breakage and confining pressure on the mechanical behaviour of ballast were investigated. Based on the experimental findings, mathematical expressions for critical state stress ratio and specific volume are proposed to incorporate the evolution of particle breakage during monotonic shearing. An elasto-plastic constitutive model is formulated within the critical state soil mechanics framework in order to capture the stress-strain behaviour and degradation of ballast. The non-linear variation of shear strength envelope at a given range of confining pressures is …


Finite Element Method Analysis Of Surface Roughness Transfer In Micro Flexible Rolling, Feijun Qu, Haibo Xie, Zhengyi Jiang Jan 2016

Finite Element Method Analysis Of Surface Roughness Transfer In Micro Flexible Rolling, Feijun Qu, Haibo Xie, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

Micro flexible rolling aims to fabricate submillimeter thick strips with varying thickness profile, where the surface quality of products is mainly determined by initial workpiece surface roughness and subsequent surface asperity flattening process, which is affected by process parameters during rolling. This paper shows a 3D finite element model for flexible rolling of a 250 μm thick workpiece with reduction of 20 to 50%, and rolling phase with thinner thickness indicates a better ability to decrease the surface roughness. Four types of initial workpiece surface roughness are studied in the simulation, and the influences of process parameters, such as friction …


Thermal Performance Evaluation And Optimal Design Of Buildings With Integrated Air-Based Photovoltaic Thermal Collectors And Phase Change Materials Using The Hooke-Jeeves Pattern Search Method, Wenye Lin, Zhenjun Ma, Paul Cooper Jan 2016

Thermal Performance Evaluation And Optimal Design Of Buildings With Integrated Air-Based Photovoltaic Thermal Collectors And Phase Change Materials Using The Hooke-Jeeves Pattern Search Method, Wenye Lin, Zhenjun Ma, Paul Cooper

Faculty of Engineering and Information Sciences - Papers: Part A

Over the last several decades, many low energy technologies have been developed and deployed to reduce building energy consumption. Among various solutions, solar photovoltaic thermal (PVT) collectors and phase change materials (PCMs) are among the most promising methods receiving increasing attention. This paper presents a thermal performance evaluation and optimal design of buildings integrated with air-based solar PVT collectors and PCMs embedded in the building envelope by using The Hooke-Jeeves pattern search method. The Hooke-Jeeves generalized pattern search is used to search for optimal solutions of the optimization problem. The variables optimized include the PVT air flow rate, additional wall …


Study On Micro Hydro-Mechanical Deep Drawing Using Finite Element Method, Xiaoguang Ma, Jingwei Zhao, Wei Du, Xin Zhang, Laizhu Jiang, Zhengyi Jiang Jan 2016

Study On Micro Hydro-Mechanical Deep Drawing Using Finite Element Method, Xiaoguang Ma, Jingwei Zhao, Wei Du, Xin Zhang, Laizhu Jiang, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part B

A numerical model was established to investigate the micro hydro-mechanical deep drawing process of austenitic stainless steel 304 foil (0.05 mm thickness). Due to the miniaturisation of the specimen size, the effect of grain size, gap distance and radial pressure during drawing process could be prominent. The results indicate that the appropriate radial pressure and gap distance could improve the limit drawing ratio (LDR) of manufactured cylindrical cups by reducing the friction resistance. The maximum LDR obtained in the present work reaches 3.2, which is much higher than that obtained by conventional deep drawing process.


Simple Method For Measuring The Linewidth Enhancement Factor Of Semiconductor Lasers, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Ginu Rajan, Qinghua Guo, Jun Tong Jan 2015

Simple Method For Measuring The Linewidth Enhancement Factor Of Semiconductor Lasers, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Ginu Rajan, Qinghua Guo, Jun Tong

Faculty of Engineering and Information Sciences - Papers: Part A

A simple method for measuring the linewidth enhancement factor (LEF) of semiconductor lasers (SLs) is proposed and demonstrated in this paper. This method is based on the self-mixing effect when a small portion of optical signal intensity emitted by the SL reflected by the moving target re-enters the SL cavity, leading to a modulation in the SL's output power intensity, in which the modulated envelope shape depends on the optical feedback strength as well as the LEF. By investigating the relationship between the light phase and power from the well-known Lang and Kobayashi equations, it was found that the LEF …


Coupled Discrete Element-Finite Difference Method For Analysing The Load-Deformation Behaviour Of A Single Stone Column In Soft Soil, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Scott W. Sloan Jan 2015

Coupled Discrete Element-Finite Difference Method For Analysing The Load-Deformation Behaviour Of A Single Stone Column In Soft Soil, Buddhima Indraratna, Ngoc Trung Ngo, Cholachat Rujikiatkamjorn, Scott W. Sloan

Faculty of Engineering and Information Sciences - Papers: Part A

Experimental studies and numerical modelling of the deformation of soft clay stabilised by stone columns have been conducted over the past few decades. Continuum-based numerical models have provided valuable insight into the prediction of settlement, lateral deformation, and stress and strain-rate dependent behaviour of stone columns at a macroscopic scale, but because they consist of granular material such as crushed rock, gravel, and waste rock aggregates, their behaviour is influenced by inter-particle micromechanics and cannot be modelled properly using these models. In this paper a novel coupled model of the discrete element method (DEM) and finite difference method (FDM) is …


A Study Of The Behaviour Of Fresh And Coal Fouled Ballast Reinforced By Geogrid Using The Discrete Element Method, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn Jan 2015

A Study Of The Behaviour Of Fresh And Coal Fouled Ballast Reinforced By Geogrid Using The Discrete Element Method, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

Geogrids are widely used in ballasted rail tracks for reinforcement and stabilisation. During train operation, ballast becomes contaminated or fouled due to infiltration of fines from the surface, mud pumping from the subgrade, and degradation, which decreases the performance of the geogrids. This paper presents the results of a laboratory and numerical simulation to study the effect that coal fines have on the interface between ballast and geogrid. The stress-strain behaviour of fresh and fouled ballast reinforced by geogrid was investigated via a series of large scale direct shear tests in the laboratory and numerical simulations using the Discrete Element …


Sensitivity Of Collapsed Arc Qa Method For Delivery Errors In Volumetric Modulated Arc Therapy (Vmat), Tony Young, Aitang Xing, Philip J. Vial, David Thwaites, Lois C. Holloway, Sankar Arumugam Jan 2015

Sensitivity Of Collapsed Arc Qa Method For Delivery Errors In Volumetric Modulated Arc Therapy (Vmat), Tony Young, Aitang Xing, Philip J. Vial, David Thwaites, Lois C. Holloway, Sankar Arumugam

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper the sensitivity of an Electronic Portal Imaging Device (EPID) to detecting introduced Volumetric Arc Therapy (VMAT) treatment errors was studied using the Collapsed Arc method. Two clinical Head and Neck (H& N) and Prostate treatment plans had gantry dependent dose and MLC errors introduced to the plans. These plans were then delivered to an Elekta Synergy Linear Accelerator EPID and compared to the original treatment planning system Collapsed Arc dose matrix. With the Collapsed Arc technique the EPID was able to detect MLC errors down to 2mm and dose errors of down to 3% depending on the …


Phase Unwrapping Method Based On Multiple Fringe Patterns Without Use Of Equivalent Wavelengths, Limei Song, Yulan Chang, Jiangtao Xi, Qinghua Guo, Xin-Jun Zhu, Xiaojie Li Jan 2015

Phase Unwrapping Method Based On Multiple Fringe Patterns Without Use Of Equivalent Wavelengths, Limei Song, Yulan Chang, Jiangtao Xi, Qinghua Guo, Xin-Jun Zhu, Xiaojie Li

Faculty of Engineering and Information Sciences - Papers: Part A

In order to decrease the noise enhancement in the process of phase unwrapping, we present a new phase unwrapping approach for multiple wavelength phase shift profilometry. In this approach, a series of fringe images with only three wavelengths are captured by the 3D measurement system, and it does not need to calculate the equivalent wavelengths and the equivalent phases. As a result, the noise enhancement is avoided, leading to improved precision in the absolute phase map recovery. Experiment results demonstrate that the proposed method is more robust and effective compared to the existing TWPSP method.


A Tensor-Based Subspace Wall Clutter Mitigation Method For Through-The-Wall Radar Imaging, Fok Hing Chi Tivive, Abdesselam Bouzerdoum Jan 2015

A Tensor-Based Subspace Wall Clutter Mitigation Method For Through-The-Wall Radar Imaging, Fok Hing Chi Tivive, Abdesselam Bouzerdoum

Faculty of Engineering and Information Sciences - Papers: Part A

In through-the-wall radar imaging, targets behind the wall reflect weak electromagnetic signals that are obscured by the strong returns from exterior wall, rendering the detection and classification of indoor stationary targets very difficult. In this paper, a tensor-based subspace method is proposed for wall clutter mitigation. The radar signals received from the antenna array are transformed into a data tensor. Higher-order singular value decomposition is used to segregate the wall reflections from the target returns. Simulation and experimental results show that the proposed method is effective in removing reflections backscattered from both homogeneous and heterogeneous walls.


Improved Method For Estimation Of Multiple Parameters In Self-Mixing Interferometry, Yan Gao, Yanguang Yu, Jiangtao Xi, Qinghua Guo, Jun Tong, Sheng Tong Jan 2015

Improved Method For Estimation Of Multiple Parameters In Self-Mixing Interferometry, Yan Gao, Yanguang Yu, Jiangtao Xi, Qinghua Guo, Jun Tong, Sheng Tong

Faculty of Engineering and Information Sciences - Papers: Part A

There are two categories of applications for self-mixing interference (SMI)-based sensing: (1) estimation of parameters associated with a semiconductor laser (SL) and (2) measurement of the metrological quantities of the external target. To achieve high resolution sensing, each category of applications requires knowledge from the other. This paper proposes an improved method that can simultaneously measure the parameters of an SL and the target movement in arbitrary form. Starting with the existing SMI model, we derive a new matrix equation for the measurement. The measurement matrix is built by employing all the available data samples obtained from an SMI signal. …


Shadow Removal Method For Phase-Shifting Profilometry, Lei Lu, Jiangtao Xi, Yanguang Yu, Qinghua Guo, Yongkai Yin, Limei Song Jan 2015

Shadow Removal Method For Phase-Shifting Profilometry, Lei Lu, Jiangtao Xi, Yanguang Yu, Qinghua Guo, Yongkai Yin, Limei Song

Faculty of Engineering and Information Sciences - Papers: Part A

In a typical phase-shifting profilometry system for the three-dimensional (3D) shape measurement, shadows often exist in the captured images as the camera and projector probe the object from different directions. The shadow areas do not reflect the fringe patterns which will cause errors in the measurement results. This paper proposed a new method to remove the shadow areas from taking part in the 3D measurement. With the system calibrated and the object reconstructed, the 3D results are mapped on a point-by-point basis into the corresponding positions on the digital micro-mirror device (DMD) of the projector. A set of roles are …


Study On Surface Asperity Flattening In Cold Quasi-Static Uniaxial Planar Compression By Crystal Plasticity Finite Element Method, Hejie Li, Zhengyi Jiang, Dongbin Wei, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong, Jingtao Han Jan 2015

Study On Surface Asperity Flattening In Cold Quasi-Static Uniaxial Planar Compression By Crystal Plasticity Finite Element Method, Hejie Li, Zhengyi Jiang, Dongbin Wei, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong, Jingtao Han

Faculty of Engineering and Information Sciences - Papers: Part A

In order to study the surface asperity flattening in a quasi-static cold uniaxial planar compression, the experimental results of atomic force microscope and electron backscattered diffraction have been employed in a ratedependent crystal plasticity model to analyze this process. The simulation results show a good agreement with the experimental results: in this quasi-static deformation process, lubrication can hinder the surface asperity flattening process even under very low deformation rate. However, due to the limitation of the model and some parameters, the simulation results cannot predict all the properties in detail such as S orientation {123}and the maximum stress in sample …


An Application Of Mathematical Morphology Operators As Features Extraction Method For Low Speed Slew Bearing Condition Monitoring, Wahyu Caesarendra, Dwi B. Wibowo, Mochammad Ariyanto, Joga D. Setiawan Jan 2015

An Application Of Mathematical Morphology Operators As Features Extraction Method For Low Speed Slew Bearing Condition Monitoring, Wahyu Caesarendra, Dwi B. Wibowo, Mochammad Ariyanto, Joga D. Setiawan

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a new application of mathematical morphology (MM) operators for low speed slew bearing condition monitoring. The MM operators were used as a signal processing step and feature extraction method for bearing vibration signals. Four basic MM operators; erosion, dilation, closing and opening, were studied. This paper also investigates another potential MM operator, namely gradient operator. Two common time domain features in bearing condition monitoring, namely root mean square (RMS) and kurtosis, were extracted from the processed signal. The study shows that the changes in bearing condition can be clearly detected from the extracted features (RMS and kurtosis) …


A Practical Tuning Method For The Robust Pid Controller With Velocity Feed-Back, Emre Sariyildiz, Haoyong Yu, Kouhei Ohnishi Jan 2015

A Practical Tuning Method For The Robust Pid Controller With Velocity Feed-Back, Emre Sariyildiz, Haoyong Yu, Kouhei Ohnishi

Faculty of Engineering and Information Sciences - Papers: Part B

Proportional-Integral-Derivative (PID) control is the most widely used control method in industrial and academic applications due to its simplicity and efficiency. Several different control methods/algorithms have been proposed to tune the gains of PID controllers. However, the conventional tuning methods do not have sufficient performance and simplicity for practical applications, such as robotics and motion control. The performance of motion control systems may significantly deteriorate by the nonlinear plant uncertainties and unknown external disturbances, such as inertia variations, friction, external loads, etc., i.e., there may be a significant discrepancy between the simulation and experiment if the robustness is not considered …


A Novel Tuning Method For Advanced Line Drop Compensator And Its Application To Response Coordination Of Distributed Generation With Voltage Regulating Devices, Kashem M. Muttaqi, An D. T Le, Michael Negnevitsky, Gerard Ledwich Jan 2014

A Novel Tuning Method For Advanced Line Drop Compensator And Its Application To Response Coordination Of Distributed Generation With Voltage Regulating Devices, Kashem M. Muttaqi, An D. T Le, Michael Negnevitsky, Gerard Ledwich

Faculty of Engineering and Information Sciences - Papers: Part A

Nowadays, integration of small-scale electricity generators, known as Distributed Generation (DG), into distribution networks has become increasingly popular. This tendency together with the falling price of DG units has a great potential in giving the DG a better chance to participate in voltage regulation process, in parallel with other regulating devices already available in the distribution systems. The voltage control issue turns out to be a very challenging problem for distribution engineers, since existing control coordination schemes need to be reconsidered to take into account the DG operation. In this paper, a control coordination approach is proposed, which is able …


Finite Element Method Analysis Of Micro Cross Wedge Rolling Of Metals, Zhengyi Jiang, Haina Lu, Dongbin Wei, Kezhi Linghu, Xianming Zhao, Xiaoming Zhang, Di Wu Jan 2014

Finite Element Method Analysis Of Micro Cross Wedge Rolling Of Metals, Zhengyi Jiang, Haina Lu, Dongbin Wei, Kezhi Linghu, Xianming Zhao, Xiaoming Zhang, Di Wu

Faculty of Engineering and Information Sciences - Papers: Part A

A newly developed manufacturing technology - micro cross wedge rolling technology is an appropriate method to produce micro axisymmetric components such as micro stepped shafts. The development of this classic cold forming process is limited by a lack of sufficient understanding of geometric and material effects due to the size reduction of the components. In this study, a numerical model is proposed to simulate micro cross wedge rolling where the grain size effect is taken into account. Pure copper is chosen as the raw material. A finite element simulation is implemented where the diameter of the cylindrical workpiece is 0.8 …


A Combined Experimental And Simulation Method For Appraising The Energy Performance Of Green Roofs In Ningbo's Chinese Climate, Georgios Kokogiannakis, Jo Darkwa, Kate Yuan Jan 2014

A Combined Experimental And Simulation Method For Appraising The Energy Performance Of Green Roofs In Ningbo's Chinese Climate, Georgios Kokogiannakis, Jo Darkwa, Kate Yuan

Faculty of Engineering and Information Sciences - Papers: Part A

A passive means of lowering the energy demand of buildings is the application of green roofs. The complexity between heat and moisture exchanges in green roof layers and the large variations of green roof types make the need for experimental or simulation assessments necessary for quantifying the energy benefits from green roofs. The current treatment of green roofs in simulation programs is either over-simplistic, for example by ignoring heat and moisture exchanges such as evapotranspiration, or the more advanced models have limitations and require inputs that are rarely available in practice. In this paper a combination of experimental and modelling …


Estimating The Magnitude Of Method Bias On Account Of Text Similarity Using A Natural Language Processing-Based Technique, Rajeev Sharma, Murad Safadi, Megan Andrews, Philip O. Ogunbona, Jeff Crawford Jan 2014

Estimating The Magnitude Of Method Bias On Account Of Text Similarity Using A Natural Language Processing-Based Technique, Rajeev Sharma, Murad Safadi, Megan Andrews, Philip O. Ogunbona, Jeff Crawford

Faculty of Engineering and Information Sciences - Papers: Part A

A number of potential biases have been identified that may contribute a spurious component to the observed correlation between variables. One such potential bias is the manner in which items are worded. This paper presents a technique and a program of research to estimate the magnitude of method bias arising from item wording. We hypothesize that the greater the level of text similarity between items employed to capture predictor and criterion variables, the greater the magnitude of the observed effect size between them. Two samples will be employed; one investigating the perceived usefulness-use correlations reported in the TAM literature and …


Grainscan: A Low Cost, Fast Method For Grain Size And Colour Measurements, Alex P. Whan, Alison Smith, C R. Cavanagh, Jean-Philippe F. Ral, Lindsay M. Shaw, Crispin A. Howitt, Leanne Bischof Jan 2014

Grainscan: A Low Cost, Fast Method For Grain Size And Colour Measurements, Alex P. Whan, Alison Smith, C R. Cavanagh, Jean-Philippe F. Ral, Lindsay M. Shaw, Crispin A. Howitt, Leanne Bischof

Faculty of Engineering and Information Sciences - Papers: Part A

Background: Measuring grain characteristics is an integral component of cereal breeding and research into genetic control of seed development. Measures such as thousand grain weight are fast, but do not give an indication of variation within a sample. Other methods exist for detailed analysis of grain size, but are generally costly and very low throughput. Grain colour analysis is generally difficult to perform with accuracy, and existing methods are expensive and involved. Results: We have developed a software method to measure grain size and colour from images captured with consumer level flatbed scanners, in a robust, standardised way. The accuracy …