Social and Behavioral Sciences Commons^™

Revisiting An Information Infrastructure For Development: Exploring The Cost Of Information In Pacific Island Development, William J. Tibben

Faculty of Engineering and Information Sciences - Papers: Part A

Information and communication technologies (ICTs) have been associated with development programmes for many decades. A theme of Lamberton's commentary on such initiatives focuses on the lack of attention given to information as a key factor in the development process. His writing reiterated a number of arguments that he saw as being fundamental to the application of an information perspective to development issues. With a focus on agricultural development policy in the Pacific region, the paper uses a number of propositions that are suggested by Lamberton to analyse contemporary development initiatives in Pacific Island agriculture. These propositions focus attention on information …

Waste Activated Sludge Hydrolysis And Acidification: A Comparison Between Sodium Hydroxide And Steel Slag Addition, Ying Zhang, Chaojie Zhang, Xuan Zhang, Leiyu Feng, Yongmei Li, Qi Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

Alkaline treatment with steel slag and NaOH addition were investigated under different pH conditions for the fermentation of waste activated sludge. Better performance was achieved in steel slag addition scenarios for both sludge hydrolysis and acidification. More solubilization of organic matters and much production of higher VFA (volatile fatty acid) in a shorter time can be achieved at pH. 10 when adjusted by steel slag. Higher enzyme activities were also observed in steel slag addition scenarios under the same pH conditions. Phosphorus concentration in the supernatant increased with fermentation time and pH in NaOH addition scenarios, while in contrast most …

Finite Time Singularities For The Locally Constrained Willmore Flow Of Surfaces, James A. Mccoy, Glen Wheeler

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper we study the steepest descent L²-gradient flow of the functional W_λ1,λ2, which is the the sum of the Willmore energy, λ1-weighted surface area, and λ2-weighted enclosed volume, for surfaces immersed in R³. This coincides with the Helfrich functional with zero `spontaneous curvature'. Our first results are a concentration-compactness alternative and interior estimates for the flow. For initial data with small energy, we prove preservation of embeddedness, and by directly estimating the Euler-Lagrange operator from below in L² we obtain that the maximal time of existence is finite. Combining this result …

Thermally Activated Paraffin-Filled Mckibben Muscles, Danial Sangian, Sina Naficy, Geoffrey M. Spinks

Faculty of Engineering and Information Sciences - Papers: Part A

McKibben artificial muscles are one of the most pragmatic contractile actuators, offering performances similar to skeletal muscles. The McKibben muscles operate by pumping pressurized fluid into a bladder constrained by a stiff braid so that tensile force generated is amplified in comparison to a conventional hydraulic ram. The need for heavy and bulky compressors/ pumps makes pneumatic or hydraulic McKibben muscles unsuitable for microactuators, where a highly compact design is required. In an alternative approach, this article describes a new type of McKibben muscle using an expandable guest fill material, such as temperature-sensitive paraffin, to achieve a more compact and …

A Comparison Of Spatial Predictors When Datasets Could Be Very Large, J R. Bradley, Noel A. Cressie, Tao Shi

Faculty of Engineering and Information Sciences - Papers: Part A

In this article, we review and compare a number of methods of spatial prediction, where each method is viewed as an algorithm that processes spatial data. To demonstrate the breadth of available choices, we consider both traditional and more-recently-introduced spatial predictors. Specifically, in our exposition we review: traditional stationary kriging, smoothing splines, negative-exponential distance-weighting, fixed rank kriging, modified predictive processes, a stochastic partial differential equation approach, and lattice kriging. This comparison is meant to provide a service to practitioners wishing to decide between spatial predictors. Hence, we provide technical material for the unfamiliar, which includes the definition and motivation for …

An Evaluation Of The Dynamics Of Diluted Neural Network, Lijuan Wang, Jun Shen, Qingguo Zhou, Zhihao Shang, Huaming Chen, Hong Zhao

Faculty of Engineering and Information Sciences - Papers: Part A

The Monte Carlo adaptation rule has been proposed to design asymmetric neural network. By adjusting the degree of the symmetry of the networks designed by this rule, the spurious memories or unwanted attractors of the networks can be suppressed completely. We have extended this rule to design full-connected neural networks and diluted neural networks. Comparing the dynamics of these two neural networks, the simulation results indicated that the performance of diluted neural network was poorer than the performance of full-connected neural network. As to this point, further research is needed. In this paper, we use the annealed dilution method to …

Shape Optimisation Of Manufacturable And Usable Cold-Formed Steel Singly-Symmetric And Open Columns, Bin Wang, Benoit P. Gilbert, Hong Guan, Lip H. Teh

Faculty of Engineering and Information Sciences - Papers: Part A

This paper aims at incorporating manufacturing and assembly features into a shape optimisation algorithm for cold-formed steel (CFS) profiles. Genetic algorithm (GA) is used as the search algorithm and is combined with the augmented Lagrangian constraint-handling method to avoid ill-conditioning. Manufacturable cross-sections are arbitrarily drawn in the initial generation and subsequently treated as an integral part of the GA. The assembly features considered in the study reflect the ones commonly encountered in the construction industry. They include fastening elements (horizontal flange and vertical web) and allowances for utilities, and are treated as constraints. The algorithm is applied to simply-supported singly-symmetric, …

Nonunital Spectral Triples And Metric Completeness In Unbounded Kk-Theory, Bram Mesland, Adam C. Rennie

Faculty of Engineering and Information Sciences - Papers: Part A

We consider the general properties of bounded approximate units in non-self-adjoint operator algebras. Such algebras arise naturally from the differential structure of spectral triples and unbounded Kasparov modules. Our results allow us to present a unified approach to characterising completeness of spectral metric spaces, existence of connections on modules, self-adjointness and regularity of induced operators on tensor product C⁎-modules and the lifting of Kasparov products to the unbounded category. In particular, we prove novel existence results for quasicentral approximate units in non-self-adjoint operator algebras, allowing us to strengthen Kasparov's technical theorem and extend it to this realm. Finally, we show …

Rolling Force Prediction In Heavy Plate Rolling Based On Uniform Differential Neural Network, Fei Zhang, Yuntao Zhao, Jian Shao

Faculty of Engineering and Information Sciences - Papers: Part A

Accurate prediction of the rolling force is critical to assuring the quality of the final product in steel manufacturing. Exit thickness of plate for each pass is calculated from roll gap, mill spring, and predicted roll force. Ideal pass scheduling is dependent on a precise prediction of the roll force in each pass. This paper will introduce a concept that allows obtaining the material model parameters directly from the rolling process on an industrial scale by the uniform differential neural network. On the basis of the characteristics that the uniform distribution can fully characterize the solution space and enhance the …

Etched Polymer Fibre Bragg Gratings, Kishore Bhowmik, Gang-Ding Peng, Yanhua Luo, Eliathamby Ambikairajah, Ginu Rajan

Faculty of Engineering and Information Sciences - Papers: Part A

Recently we initiated a new research direction for high-sensitivity and high-reflectivity Bragg grating fabrication based on etched polymer optical fibre, here we report the recent research developments on etched polymer fibre Bragg gratings.

Rational And Self-Adaptive Evolutionary Extreme Learning Machine For Electricity Price Forecast, Chixin Xiao, Zhao Y. Dong, Yan Xu, Ke Meng, Xun Zhou, Xin Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

Electricity price forecast is of great importance to electricity market participants. Given the sophisticated time-series of electricity price, various approaches of extreme learning machine (ELM) have been identified as effective prediction approaches. However, in high dimensional space, evolutionary extreme learning machine (E-ELM) is time-consuming and difficult to converge to optimal region when just relying on stochastic searching approaches. In the meanwhile, due to the complicated functional relationship, objective function of E-ELM seems difficult also to be mined directly for some useful mathematical information to guide the optimum exploring. This paper proposes a new differential evolution (DE) like algorithm to enhance …

Pedestrian Lane Detection In Unstructured Scenes For Assistive Navigation, Son Lam Phung, Cuong Le Manh, Abdesselam Bouzerdoum

Faculty of Engineering and Information Sciences - Papers: Part A

Automatic detection of the pedestrian lane in a scene is an important task in assistive and autonomous navigation. This paper presents a vision-based algorithm for pedestrian lane detection in unstructured scenes, where lanes vary significantly in color, texture, and shape and are not indicated by any painted markers. In the proposed method, a lane appearance model is constructed adaptively from a sample image region, which is identified automatically from the image vanishing point. This paper also introduces a fast and robust vanishing point estimation method based on the color tensor and dominant orientations of color edge pixels. The proposed pedestrian …

Water Reclamation And Nitrogen Extraction From Municipal Solid Waste Landfill Leachate, Long D. Nghiem, Faisal I. Hai, Andre Listowski

Faculty of Engineering and Information Sciences - Papers: Part A

This study aims to explore several innovative technologies including electrocoagulation, nanofiltration (NF), membrane distillation (MD), and ion exchange resin for clean water extraction and resource recovery from landfill leachate. Our results demonstrate the technical feasibility of water reuse and ammonia recovery from landfill leachate. Electrocoagulation was effective as a pretreatment step for the NF process and could remove most suspended solids and some organic matter. The results show that the combination of NF and MD can produce high-quality water from landfill leachate suitable for reuse applications with respect to heavy metals (with the exception of arsenic) and pharmaceutically active compounds …

Structural Behaviours Of Railway Prestressed Concrete Sleepers (Crossties) With Hole And Web Openings, Sakdirat Kaewunruen, Erosha Kahawatta Gamage, Alex M. Remennikov

Faculty of Engineering and Information Sciences - Papers: Part A

As the crosstie beam in railway track systems, the prestressed concrete sleepers (or railroad ties) are principally designed in order to carry wheel loads from the rails to the ground. Their design takes into account static and dynamic loading conditions. It is evident that prestressed concrete has played a significant role as to maintain the high endurance of the sleepers under low to moderate repeated impact loads. In spite of the most common use of the prestressed concrete sleepers in railway tracks, there have always been considerable demands from rail and track engineers to improve serviceability and functionality of concrete …

Review Of Geant4-Dna Applications For Micro And Nanoscale Simulations, Sebastien Incerti, Michael Douglass, Scott Penfold, Susanna Guatelli, Eva Bezak

Faculty of Engineering and Information Sciences - Papers: Part A

Emerging radiotherapy treatments including targeted particle therapy, hadron therapy or radiosensitisation of cells by high-Z nanoparticles demand the theoretical determination of radiation track structure at the nanoscale. This is essential in order to evaluate radiation damage at the cellular and DNA level. Since 2007, Geant4 offers physics models to describe particle interactions in liquid water at the nanometre level through the Geant4-DNA Package. This package currently provides a complete set of models describing the event-by-event electromagnetic interactions of particles with liquid water, as well as developments for the modelling of water radiolysis. Since its release, Geant4-DNA has been adopted as …

Development Of A Bio-Inspired Transformable Robotic Fin, Yikun Yang, Yu Xia, Fenghua Qin, Min Xu, Weihua Li, Shiwu Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

Fish swim by oscillating their pectoral fins forwards and backwards in a cyclic motion such that their geometric parameters and aspect ratios change according to how fast or slow a fish wants to swim; these complex motions result in a complicated hydrodynamic response. This paper focuses on the dynamic change in the shape of a fin to improve the underwater propulsion of bio-inspired mechanism. To do this, a novel transformable robotic fin has been developed to investigate how this change in shape affects the hydrodynamic forces acting on the fin. This robotic fin has a multi-link frame and a flexible …

Comprehensive Performance Analysis Of Fully Cooperative Communication In Wbans, Le Chung Tran, Alfred Mertins, Xiaojing Huang, Farzad Safaei

Faculty of Engineering and Information Sciences - Papers: Part A

While relay-based cooperative networks (widely known in the literature as cooperative communication), where relays only forward signals from the sources to the destination, have been extensively researched, fully cooperative systems have not been thoroughly examined. Unlike relay networks, in a fully cooperative network, each node acts as both a source node sending its own data and a relay forwarding its partner's data to the destination. Mutual cooperation between neighboring nodes is believed to improve the overall system error performance, especially when space-time codes are incorporated. However, a comprehensive performance analysis of space-time-coded fully cooperative communication from all three perspectives, namel,y …

Modified Centrifugal Technique For Determining Polymer Demand And Achievable Dry Solids Content In The Dewatering Of Anaerobically Digested Sludge, Vu Hien Phuong To, Tien Vinh Nguyen, Saravanamuthu Vigneswaran, Long D. Nghiem, Sudhir Murthy, Heriberto A. Bustamante, Matthew Higgins

Faculty of Engineering and Information Sciences - Papers: Part A

This study aims to characterize anaerobically digested sludge (ADS) and correlate the sludge characteristics in terms of soluble organic compounds with polymer demand (PD) during sludge conditioning. The PD required to achieve maximum dewatering of the ADS studied is in the range of 8-10 kg polymer/dry ton. The commonly used capillary suction time parameter to evaluate the solid-liquid separation ability was not a reliable indicator for assessing dewatering. Instead, in this study, a modified centrifugal technique proposed by Higgins (Higgins MCT) was used to assess the maximum achievable dry solids content of the biosolids cake. The Higgins MCT is readily …

Response Of Rigid Piles During Passive Dragging, Wei Dong Guo

Faculty of Engineering and Information Sciences - Papers: Part A

This paper develops a three-layer model and elastic solutions to capture nonlinear response of rigid, passive piles in sliding soil. Elastic solutions are obtained for an equivalent force per unit length p_s of the soil movement. They are repeated for a series of linearly increasing p_s (with depth) to yield the nonlinear response. The parameters underpinning the model are determined against pertinent numerical solutions and model tests on passive free-head and capped piles. The solutions are presented in non-dimensional charts and elaborated through three examples. The study reveals the following:

• On-pile pressure in rotationally restrained, sliding layer reduces …

A Review Of Shear Strength Models For Rock Joints Subjected To Constant Normal Stiffness, Sivanathan Thirukumaran, Buddhima Indraratna

Faculty of Engineering and Information Sciences - Papers: Part A

The typical shear behaviour of rough joints has been studied under constant normal load/stress (CNL) boundary conditions, but recent studies have shown that this boundary condition may not replicate true practical situations. Constant normal stiffness (CNS) is more appropriate to describe the stress-strain response of field joints since the CNS boundary condition is more realistic than CNL. The practical implications of CNS are movements of unstable blocks in the roof or walls of an underground excavation, reinforced rock wedges sliding in a rock slope or foundation, and the vertical movement of rock-socketed concrete piles. In this paper, the highlights and …

Comparison Of Setup Accuracy Of Three Different Image Assessment Methods For Tangential Breast Radiotherapy, Vikneswary Batumalai, Penny Phan, Callie Choong, Lois C. Holloway, Geoff P. Delaney

Faculty of Engineering and Information Sciences - Papers: Part A

Introduction

To compare the differences in setup errors measured with electronic portal image (EPI) and cone-beam computed tomography (CBCT) in patients undergoing tangential breast radiotherapy (RT). Relationship between setup errors, body mass index (BMI) and breast size was assessed.

Methods

Twenty-five patients undergoing postoperative RT to the breast were consented for this study. Weekly CBCT scans were acquired and retrospectively registered to the planning CT in three dimensions, first using bony anatomy for bony registration (CBCT-B) and again using breast tissue outline for soft tissue registration (CBCT-S). Digitally reconstructed radiographs (DRR) generated from CBCT to simulate EPI were compared to …

Superstrength Of Nanograined Steel With Nanoscale Intermetallic Precipitates Transformed From Shock-Compressed Martensitic Steel, Hai Liang Yu, Ming Yan, Cheng Lu, Anh Kiet Tieu, Hui Jun Li, Qiang Zhu, Ajit R. Godbole, Jintao Li, Lihong Su, Charlie Kong

Faculty of Engineering and Information Sciences - Papers: Part A

An increasing number of industrial applications need superstrength steels. It is known that refined grains and nanoscale precipitates can increase strength. The hardest martensitic steel reported to date is C0.8 steel, whose nanohardness can reach 11.9 GPa through incremental interstitial solid solution strengthening. Here we report a nanograined (NG) steel dispersed with nanoscale precipitates which has an extraordinarily high hardness of 19.1 GPa. The NG steel (shock-compressed Armox 500T steel) was obtained under these conditions: high strain rate of 1.2 μs⁻¹, high temperature rise rate of 600 Kμs⁻¹ and high pressure of 17 GPa. The mean grain …

Tunable Particle Focusing In A Straight Channel With Symmetric Semicircle Obstacle Arrays Using Electrophoresis-Modified Inertial Effects, Dan Yuan, Chao Pan, Jun Zhang, Sheng Yan, Qianbin Zhao, Gursel Alici, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

In this work, a novel microfluidic platform for tunable particle focusing in a straight channel with symmetric semicircle obstacle arrays using electrophoresis (EP)-modified inertial effects was presented. By exerting an EP force on the charged microparticles, a relative velocity gap between microspheres and fluid in a straight channel with symmetric semicircle obstacle arrays was implemented. The relative velocity and fluid shear will induce shear-slip lift force (Saffman lift force) perpendicular to the mainstream direction. Therefore, the focusing pattern can be altered using the electrophoresis-induced Saffman force. The effects of electric field direction, flow rate, electric field magnitude, and particle size …

A Seat Suspension With A Rotary Magnetorheological Damper For Heavy Duty Vehicles, Shuaishuai Sun, Donghong Ning, Jian Yang, Haiping Du, Shiwu Zhang, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the development of an innovative seat suspension working with a rotary magnetorheological (MR) fluid damper. Compared with a conventional linear MR damper, the well-designed rotary MR damper possesses several advantages such as usage reduction of magnetorheological fluid, low sealing requirements and lower costs. This research starts with the introduction of the seat suspension structure and the damper design, followed by the property test of the seat suspension using an MTS machine. The field-dependent property, amplitudedependent performance, and the frequency-dependent performance of the new seat suspension are measured and evaluated. This research puts emphasis on the evaluation of …

Deadband Control Of Doubly-Fed Induction Generator Around Synchronous Speed, Yingjie Tan, Kashem M. Muttaqi, Lasantha G. Meegahapola, Phil Ciufo

Faculty of Engineering and Information Sciences - Papers: Part A

Semiconductor devices in power electronic converters of the doubly-fed induction generator (DFIG) are susceptible to significant junction temperature variations when operating around synchronous speed, thereby reducing the lifetime of the converters. This is due to the fact that the frequency of the rotor current in a DFIG is determined by the stator flux frequency and rotor speed, and hence will lead to low rotor current frequency when operating closer to the synchronous speed, and ultimately result in significant thermal stress on semiconductor devices. In this paper, a multimode operation control strategy is proposed for the DFIG to prevent operating around …

An Intelligent Driver Alerting System For Real-Time Range Indicator Embedded In Electric Vehicles, Kaveh Sarrafan, Kashem M. Muttaqi, Danny Sutanto, Graham Town

Faculty of Engineering and Information Sciences - Papers: Part A

This paper proposes a state-of-the-art algorithm for a real time charging recommendation for an electric vehicle (EV) driver based on an accurate real-time range indicator system to avoid range anxiety. The charging recommendation algorithm alerts the driver when charging is deemed required for the selected route. This algorithm determines the nearest charging location obtained using GPS based on an accurate estimation of SoC at the destination and when charging determines the optimum charging time required by the battery to have sufficient energy to reach the destination. The graphical user interface (GUI) of the real-time range indicator system is also used …

Development Of Intermediate Cooling Technology And Its Control For Two-Stand Plate Rolling, Fei Zhang, Wei Yu, Tao Liu

Faculty of Engineering and Information Sciences - Papers: Part A

In a plate rolling production line, thermomechanically controlled processing is critical for plate quality. In this paper, a set of intermediate cooling equipment of a two-stand plate mill with super density nozzles, medium pressure, and small flow is developed. Based on a simplified dynamic model, a cooling control scheme with combined feedforward, feedback, and adaptive algorithms is put forward. The new controlled rolling process and the highly efficient control system improve the controlled rolling efficiency by an average of 17.66%. The proposed intermediate cooling system can also effectively inhibit the growth of austenite grain, improve the impact toughness and yield …

Uniqueness Of Solutions To A Nonlinear Elliptic Hessian Equation, Siyuan Li

Faculty of Engineering and Information Sciences - Papers: Part A

Through an Alexandrov-Fenchel inequality, we establish the general Brunn-Minkowski inequality. Then we obtain the uniqueness of solutions to a nonlinear elliptic Hessian equation on Sn.

A Wideband F-Shaped Patch Antenna For S-Band Cubesats Communications, Faisel Em M Tubbal, Raad Raad, Kwan-Wu Chin

Faculty of Engineering and Information Sciences - Papers: Part A

A wideband S-band F-shaped patch antenna is proposed for CubeSats communications. To broaden bandwidth, it uses two arms with different lengths to generate a second resonant frequency. The effect of the arm length and width on the return loss, resonant frequency and impedance bandwidth on a 3U CubeSat is studied. The simulation results show that the antenna achieves a wideband of 1121 MHz (1.606-2.727 GHz) with a return loss below −10 dB over the entire frequency band from 1.606 to 2.727 GHz. The antenna has a high gain of 8.51 dB and a small return loss of −32.85 dB at …

Dipole Antenna Array Cluster For Cubesats, Sining Liu, Raad Raad, Kwan-Wu Chin, Faisel Em M Tubbal

Faculty of Engineering and Information Sciences - Papers: Part A

CubeSats are attracting interest from both the industry and academia because of their affordability. Specifically, they are made from commercial Off-The-Shelf (COTS) electronic circuit chips, and are thus seen as a cost effective replacement for traditional, expensive satellites. Moreover, they are expected to have higher capabilities to better support demanding missions. To date, most CubeSats rely on a single element antenna that usually has a relatively low gain and are not steerable. Thus, they are not suitable for long-distance communications and for use by missions requiring high-speed links and adjustable radiation patterns. Existing single element antennas also increase the probability …