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Full-Text Articles in Social and Behavioral Sciences

Selection Of Forward Osmosis Draw Solutes For Subsequent Integration With Anaerobic Treatment To Facilitate Resource Recovery From Wastewater, Ashley J. Ansari, Faisal I. Hai, Wenshan Guo, Hao H. Ngo, William E. Price, Long D. Nghiem Jan 2015

Selection Of Forward Osmosis Draw Solutes For Subsequent Integration With Anaerobic Treatment To Facilitate Resource Recovery From Wastewater, Ashley J. Ansari, Faisal I. Hai, Wenshan Guo, Hao H. Ngo, William E. Price, Long D. Nghiem

Faculty of Engineering and Information Sciences - Papers: Part A

Forward osmosis (FO) can be used to extract clean water and pre-concentrate municipal wastewater to make it amenable to anaerobic treatment. A protocol was developed to assess the suitability of FO draw solutes for pre-concentrating wastewater for potential integration with anaerobic treatment to facilitate resource recovery from wastewater. Draw solutes were evaluated in terms of their ability to induce osmotic pressure, water flux, and reverse solute flux. The compatibility of each draw solute with subsequent anaerobic treatment was assessed by biomethane potential analysis. The effect of each draw solute (at concentrations corresponding to the reverse solute flux at ten-fold pre-concentration ...


Oxide Scale Characterization Of Ferritic Stainless Steel And Its Deformation And Friction In Hot Rolling, Xiawei Cheng, Zhengyi Jiang, Dongbin Wei, Liang Hao, Jingwei Zhao, Laizhu Jiang Jan 2015

Oxide Scale Characterization Of Ferritic Stainless Steel And Its Deformation And Friction In Hot Rolling, Xiawei Cheng, Zhengyi Jiang, Dongbin Wei, Liang Hao, Jingwei Zhao, Laizhu Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

The oxidation kinetics of ferritic stainless steel 430 was studied in dry and humid air at 1090 °C by Thermo Gravimetric Analysis (TGA). Different atmospheres and heating times were adopted for reheating to obtain different compositions and thickness of the oxide scale. Hot rolling was performed on a 2-high Hille 100 experimental rolling mill at various reductions. Oxide scale thickness and composition were analysed with optical microscopy (OM), scanning electron microscope (SEM) and X-ray diffraction (XRD). The surface profiles were examined by a digital microscope, and the topographic features of the thin oxide scale surface were examined with an atomic ...


A Multi-Objective Design Optimization Strategy For Vertical Ground Heat Exchangers, Su Huang, Zhenjun Ma, Fenghao Wang Jan 2015

A Multi-Objective Design Optimization Strategy For Vertical Ground Heat Exchangers, Su Huang, Zhenjun Ma, Fenghao Wang

Faculty of Engineering and Information Sciences - Papers: Part A

A multi-objective design optimization strategy for vertical U-tube ground heat exchangers (GHEs) is presented to minimize the system upfront cost and entropy generation number simultaneously. Five design variables of vertical U-tube GHEs, including borehole number, borehole depth, borehole radius, U-tube outer radius and fluid mass flow rate, are first selected via a global sensitivity analysis method, and then optimized by a genetic algorithm (GA) optimizer implemented in MATLAB. Based on the Pareto frontier obtained from the GA optimization, a decision-making strategy is then used to determine a final solution. Two case studies are presented to validate the effectiveness of the ...


Crystal Plasticity Finite Element Method Modelling Of Indentation Size Effect, Mao Liu, Cheng Lu, A Kiet Tieu Jan 2015

Crystal Plasticity Finite Element Method Modelling Of Indentation Size Effect, Mao Liu, Cheng Lu, A Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part A

A crystal plasticity finite element method (CPFEM) model has been developed to investigate the indentation size effect (ISE) of aluminium single crystal during nano-indentation. The simulated results have been validated by comparison with experimental observations. The load-hardness curves from simulation are consistent with the experimental results. The mathematic relationship between load and indentation depth has been built to investigate indentation size effect. In addition, the Mises stress, critical resolved shear stress, stress and shear strain rates for a selected element and the lattice curvature have been studied to explain indentation size effect.


Optimisation Of Coal Wash-Slag Blend As A Structural Fill, Gabriele Chiaro, Buddhima Indraratna, S.M.Ali Tasalloti, Cholachat Rujikiatkamjorn Jan 2015

Optimisation Of Coal Wash-Slag Blend As A Structural Fill, Gabriele Chiaro, Buddhima Indraratna, S.M.Ali Tasalloti, Cholachat Rujikiatkamjorn

Faculty of Engineering and Information Sciences - Papers: Part A

Coal wash (CW) and basic oxygen steel slag fines (BOS) are by-products of the coal mining and steel industries, respectively. Their effective reuse and recycling through large-scale geotechnical projects, such as port reclamation, is economically beneficial and environmentally sustainable. In this study, CW and BOS were blended in order to explore the possibility to obtain synthetic fills having geotechnical properties similar or superior to conventional fills, therefore suitable as a structural fill for the Port Kembla Outer Harbour reclamation near Wollongong City, Australia. A framework with four levels of acceptance is proposed in this paper to select granular waste as ...


Facilitating An Ant Colony Algorithm For Multi-Objective Data-Intensive Service Provisions, Lijuan Wang, Jun Shen, Junzhou Luo Jan 2015

Facilitating An Ant Colony Algorithm For Multi-Objective Data-Intensive Service Provisions, Lijuan Wang, Jun Shen, Junzhou Luo

Faculty of Engineering and Information Sciences - Papers: Part A

The explosion of enormous sources of digital data has led to greater dependence on data-intensive services. Applications based on data-intensive services have become one of the most challenging applications in cloud computing. The service provision, and in particular service composition, will face new challenges as the services and data grow. In this paper, we will evaluate an ant colony system to resolve the multi-objective data-intensive service composition problem. The algorithm for a multi-objective context will get a set of Pareto-optimal solutions considering two objectives at the same time: the total cost and the total execution time of a composite service.


Ambiguous Optimistic Fair Exchange: Definition And Constructions, Qiong Huang, Guomin Yang, Duncan Wong, Willy Susilo Jan 2015

Ambiguous Optimistic Fair Exchange: Definition And Constructions, Qiong Huang, Guomin Yang, Duncan Wong, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part A

Optimistic fair exchange (OFE) is a protocol for solving the problem of exchanging items or services in a fair manner between two parties, a signer and a verifier, with the help of an arbitrator which is called in only when a dispute happens between the two parties. In almost all the previous work on OFE, after obtaining a partial signature from the signer, the verifier can present it to others and show that the signer has indeed committed itself to something corresponding to the partial signature evenprior to the completion of the transaction. In some scenarios, this capability given to ...


Efficient Algorithms For Secure Outsourcing Of Bilinear Pairings, Xiaofeng Chen, Willy Susilo, Jin Li, Duncan Wong, Jianfeng Ma, Shaohua Tang, Qiang Tang Jan 2015

Efficient Algorithms For Secure Outsourcing Of Bilinear Pairings, Xiaofeng Chen, Willy Susilo, Jin Li, Duncan Wong, Jianfeng Ma, Shaohua Tang, Qiang Tang

Faculty of Engineering and Information Sciences - Papers: Part A

The computation of bilinear pairings has been considered the most expensive operation in pairing-based cryptographic protocols. In this paper, we first propose an efficient and secure outsourcing algorithm for bilinear pairings in the two untrusted program model. Compared with the state-of-the-art algorithm, a distinguishing property of our proposed algorithm is that the (resource-constrained) outsourcer is not required to perform any expensive operations, such as point multiplications or exponentiations. Furthermore, we utilize this algorithm as a subroutine to achieve outsource-secure identity-based encryptions and signatures.


A Short Identity-Based Proxy Ring Signature Scheme From Rsa, Maryam Rjabzadeh Asaar, Mahmoud Salmasizadeh, Willy Susilo Jan 2015

A Short Identity-Based Proxy Ring Signature Scheme From Rsa, Maryam Rjabzadeh Asaar, Mahmoud Salmasizadeh, Willy Susilo

Faculty of Engineering and Information Sciences - Papers: Part A

Identity-based proxy ring signature concept was introduced by Cheng et al. in 2004. This primitive is useful where the privacy of proxy signers is required. In this paper, the first short provably secure identity-based proxy ring signature scheme from RSA assumption has been proposed. In addition, the security of the proposed scheme tightly reduces to the RSA assumption, and therefore, the proposed scheme has a proper advantage in security reduction compared to the ones from RSA. The proposed scheme not only outperforms the existing schemes in terms of efficiency and practicality, but also does not suffer from the proxy key ...


Enhanced Tensile Properties Of Aluminium Matrix Composites Reinforced With Graphene Encapsulated Sic Nanoparticles, Alireza Fadavi Boostani, S Tahamtan, Zhengyi Jiang, Dongbin Wei, Siamak Yazdani, R Azari Khosroshahi, R Taherzadeh Mousavian, Jianzhong Xu, X M. Zhang, Dianyao Gong Jan 2015

Enhanced Tensile Properties Of Aluminium Matrix Composites Reinforced With Graphene Encapsulated Sic Nanoparticles, Alireza Fadavi Boostani, S Tahamtan, Zhengyi Jiang, Dongbin Wei, Siamak Yazdani, R Azari Khosroshahi, R Taherzadeh Mousavian, Jianzhong Xu, X M. Zhang, Dianyao Gong

Faculty of Engineering and Information Sciences - Papers: Part A

Due to a high propensity of nano-particles to agglomerate, making aluminium matrix composites with a uniform dispersion of the nano-particles using liquid routes is an exceptionally difficult task. In this study, an innovative approach was utilised to prevent agglomeration of nano-particle by encapsulating SiC nano-particles using graphene sheets during ball milling. Subsequently, the milled mixture was incorporated into A356 molten alloy using non-contact ultrasonic vibration method. Two different shapes for graphene sheets were characterised using HRTEM, including onion-like shells encapsulating SiC particles and disk-shaped graphene nanosheets. This resulted in 45% and 84% improvement in yield strength and tensile ductility, respectively ...


High Strength And Ductility Of Ultrathin Laminate Foils Using Accumulative Roll Bonding And Asymmetric Rolling, Hailiang Yu, A Kiet Tieu, Syamsul Hadi, Cheng Lu, Ajit R. Godbole, Charlie Kong Jan 2015

High Strength And Ductility Of Ultrathin Laminate Foils Using Accumulative Roll Bonding And Asymmetric Rolling, Hailiang Yu, A Kiet Tieu, Syamsul Hadi, Cheng Lu, Ajit R. Godbole, Charlie Kong

Faculty of Engineering and Information Sciences - Papers: Part A

As product miniaturization is becoming widely popular, many microparts are being produced by microforming of sheets/foils, whose strength needs to be able to maintain structural stability of the micro-components. In addition, their strength and ductility of foils generally reduce with a reduction in the thickness due to the size effect. In this paper, we report the fabrication of an aluminum laminate foil using a combined process of accumulative roll bonding (ARB) and asymmetric rolling (AR). It was found that this improves both strength and ductility. TEM results show that the laminate structures produced by ARB develop an inhomogeneous microstructure ...


A Multi-Bead Overlapping Model For Robotic Wire And Arc Additive Manufacturing (Waam), Donghong Ding, Zengxi Pan, Dominic Cuiuri, Huijun Li Jan 2015

A Multi-Bead Overlapping Model For Robotic Wire And Arc Additive Manufacturing (Waam), Donghong Ding, Zengxi Pan, Dominic Cuiuri, Huijun Li

Faculty of Engineering and Information Sciences - Papers: Part A

Wire and arc additive manufacturing (WAAM) is a promising alternative to traditional subtractive manufacturing for fabricating large aerospace components that feature high buy-to-fly ratio. Since the WAAM process builds up a part with complex geometry through the deposition of weld beads on a layer-by-layer basis, it is important to model the geometry of a single weld bead as well as the multi-bead overlapping process in order to achieve high surface quality and dimensional accuracy of the fabricated parts. This study firstly builds models for a single weld bead through various curve fitting methods. The experimental results show that both parabola ...


Excellent Melt Lubrication Of Alkali Metal Polyphosphate Glass For High Temperature Applications, A Kiet Tieu, Shanhong Wan, Ning Kong, Qiang Zhu, Hongtao Zhu Jan 2015

Excellent Melt Lubrication Of Alkali Metal Polyphosphate Glass For High Temperature Applications, A Kiet Tieu, Shanhong Wan, Ning Kong, Qiang Zhu, Hongtao Zhu

Faculty of Engineering and Information Sciences - Papers: Part A

A new class of high temperature lubricant of inorganic alkali metal polyphosphate was developed for hot metal forming, which involved a fundamental knowledge of melt lubrication. At elevated temperature a 55% reduction in friction and a 50% decrease in wear were achieved by the presence of the molten polyphosphate lubrication, as well as the excellent anti-oxidation capability at the rubbing steel/steel interface, which closely correlated with the tribo-induced hierarchical structure at the rubbing interface. This inorganic polyphosphate lubricant can be called a smart polymeric material, which will be an eco-friendly alternative for high temperature applications. This journal is


Urinary Continence Care In Australian Nursing Homes, Ping Yu, Victoria Traynor, David Hailey Jan 2015

Urinary Continence Care In Australian Nursing Homes, Ping Yu, Victoria Traynor, David Hailey

Faculty of Engineering and Information Sciences - Papers: Part A

Objective Exploring urinary continence (UC) assessment and management practices in Australian nursing homes. Design Mixed method using a questionnaire and interviews. Setting Five nursing homes in Australian metropolitan cities. Subjects Participants 121 staff: mostly female (91%) with a range of roles including personal care assistants (PCAs) (63%), enrolled nurses (ENs) (11%), registered nurses (RNs) (20%) and managers (4%). Main outcomes measure(s) Compliance with and perceptions about UC assessment and management. Results 77% (n=71) of care staff (PCAs, ENs and RNs) were compliant with the UC management protocol of checking for wetness every 2 to 2.5 hours. Toileting ...


The Evaluation Of A 2d Diode Array In "Magic Phantom" For Use In High Dose Rate Brachytherapy Pretreatment Quality Assurance, Anthony A. Espinoza, Marco Petasecca, Iolanda Fuduli, Andrew Howie, Joseph A. Bucci, Stephanie Corde, Michael Jackson, Michael L. F Lerch, Anatoly B. Rosenfeld Jan 2015

The Evaluation Of A 2d Diode Array In "Magic Phantom" For Use In High Dose Rate Brachytherapy Pretreatment Quality Assurance, Anthony A. Espinoza, Marco Petasecca, Iolanda Fuduli, Andrew Howie, Joseph A. Bucci, Stephanie Corde, Michael Jackson, Michael L. F Lerch, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part A

Purpose: High dose rate (HDR) brachytherapy is a treatment method that is used increasingly worldwide. The development of a sound quality assurance program for the verification of treatment deliveries can be challenging due to the high source activity utilized and the need for precise measurements of dwell positions and times. This paper describes the application of a novel phantom, based on a 2D 11 x 11 diode array detection system, named "magic phantom" (MPh), to accurately measure plan dwell positions and times, compare them directly to the treatment plan, determine errors in treatment delivery, and calculate absorbed dose. Methods: The ...


Permeable Reactive Barrier Rejuvenation By Alkaline Wastewater, Laura Banasiak, Buddhima Indraratna, Glenys Lugg, Udeshini Pathirage, Geoffrey Mcintosh, Neil Rendell Jan 2015

Permeable Reactive Barrier Rejuvenation By Alkaline Wastewater, Laura Banasiak, Buddhima Indraratna, Glenys Lugg, Udeshini Pathirage, Geoffrey Mcintosh, Neil Rendell

Faculty of Engineering and Information Sciences - Papers: Part A

Chemical armouring of recycled concrete in a permeable reactive barrier (PRB) used for the neutralisation of acidic groundwater in acid sulfate soil terrain significantly decreases its acid neutralising capacity (ANC) by approximately 50% compared with its theoretical ANC. A long-term column test was conducted under simulated field groundwater conditions to assess the re-conditioning of armoured recycled concrete aggregates with alkaline wastewater, with the aim to restore and enhance the ANC and longevity of the PRB. The benefits of alkaline wastewater injection included sharp but short enhancement of the recycled concretes' ANC, as indicated by an increase in effluent pH (pH ...


Validating The Rejection Of Trace Organic Chemicals By Reverse Osmosis Membranes Using A Pilot-Scale System, Takahiro Fujioka, Stuart Khan, James Mcdonald, Long D. Nghiem Jan 2015

Validating The Rejection Of Trace Organic Chemicals By Reverse Osmosis Membranes Using A Pilot-Scale System, Takahiro Fujioka, Stuart Khan, James Mcdonald, Long D. Nghiem

Faculty of Engineering and Information Sciences - Papers: Part A

A protocol to validate the rejection of organic chemicals of potential health risk by low pressure reverse osmosis (LPRO) membranes was developed for decision making support regarding the monitoring level required for potable water reuse. Ten organic chemicals were selected for evaluation, based on their recorded usage, the scarcity of rejection data, and difficulty in analytical determination at concentrations relevant to their potential impact on human-health. An analytical method was developed for these organic chemicals. The target rejections of 90 and 99% for neutral and charged chemicals respectively were successfully achieved under the standard operating condition with only two exceptions ...


Numerical Simulations Of Response Of Tubular Steel Beams To Close-Range Explosions, Tuan D. Ngo, Damith Mohotti, Alex M. Remennikov, Brian Uy Jan 2015

Numerical Simulations Of Response Of Tubular Steel Beams To Close-Range Explosions, Tuan D. Ngo, Damith Mohotti, Alex M. Remennikov, Brian Uy

Faculty of Engineering and Information Sciences - Papers: Part A

A numerical study of hollow and concrete-filled square tubular steel columns subjected to near-field detonations has been undertaken and validated through the experimental results. The experiments used concrete-filled and hollow square tubular columns (100 x 5 mm SHS Grade C350) made out of cold-formed structural steel hollow sections (SHS) that were simply supported at both ends. High explosives TNT charges were placed above the top surface of the column at two different scaled standoff distances of 0.12 m/kg1/3 and 0.15 m/kg1/3. Failure patterns and permanent mid-span deformations were recorded and compared with the numerical ...


Effective Utilization Of Excess Energy In Standalone Hybrid Renewable Energy Systems For Improving Comfort Ability And Reducing Cost Of Energy: A Review And Analysis, M Ismail Ismail, Mahmoud Moghavvemi, T Mahlia, Kashem M. Muttaqi, S Moghavvemi Jan 2015

Effective Utilization Of Excess Energy In Standalone Hybrid Renewable Energy Systems For Improving Comfort Ability And Reducing Cost Of Energy: A Review And Analysis, M Ismail Ismail, Mahmoud Moghavvemi, T Mahlia, Kashem M. Muttaqi, S Moghavvemi

Faculty of Engineering and Information Sciences - Papers: Part A

One of the features that characterize renewable energy sources is their variability and intermittency. Intermittency covers both the predictable and unpredictable variations of their power outputs and uncertainty in the power availability. To overcome the drawback of intermittency, special design considerations should be taken into account. These additional design considerations increases the overall cost of the renewable energy systems. Adding storage system and/or backup source to the renewable sources is one of the measures used to guarantee the continuity of power supply to the loads, and therefore improve the reliability of the renewable energy systems. The operation of renewable ...


Nonlinear Bilateral Teleoperation Using Extended Active Observer For Force Estimation And Disturbance Suppression, Linping Chan, Fazel Naghdy, David Stirling, Matthew Field Jan 2015

Nonlinear Bilateral Teleoperation Using Extended Active Observer For Force Estimation And Disturbance Suppression, Linping Chan, Fazel Naghdy, David Stirling, Matthew Field

Faculty of Engineering and Information Sciences - Papers: Part A

A novel nonlinear teleoperation algorithm for simultaneous inertial parameters and force estimation at the master and slave sides of the teleoperation system is proposed. The scheme, called Extended Active Observer (EAOB), is an extension of the existing active observer. It provides effective force tracking at the master side with accurate position tracking at the slave side in the presence of inertial parameter variation and measurement noise. The proposed method only requires the measurement of robot position, and as a result significantly reduces the difficulty and cost of implementing bilateral teleoperation systems. The approach is described and its stability is analytically ...


A Variance Inflation Factor And Backward Elimination Based Robust Regression Model For Forecasting Monthly Electricity Demand Using Climatic Variables, Dao Hoang Vu, Kashem M. Muttaqi, Ashish Agalgaonkar Jan 2015

A Variance Inflation Factor And Backward Elimination Based Robust Regression Model For Forecasting Monthly Electricity Demand Using Climatic Variables, Dao Hoang Vu, Kashem M. Muttaqi, Ashish Agalgaonkar

Faculty of Engineering and Information Sciences - Papers: Part A

Selection of appropriate climatic variables for prediction of electricity demand is critical as it affects the accuracy of the prediction. Different climatic variables may have different impacts on the electricity demand due to the varying geographical conditions. This paper uses multicollinearity and backward elimination processes to select the most appropriate variables and develop a multiple regression model for monthly forecasting of electricity demand. The former process is employed to reduce the collinearity between the explanatory variables by excluding the predictor which has highly linear relationship with the other independent variables in the dataset. In the next step, involving backward elimination ...


On Asymptotic Behaviour And W 2, P Regularity Of Potentials In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang Jan 2015

On Asymptotic Behaviour And W 2, P Regularity Of Potentials In Optimal Transportation, Jiakun Liu, Neil Trudinger, Xu-Jia Wang

Faculty of Engineering and Information Sciences - Papers: Part A

© 2014, Springer-Verlag Berlin Heidelberg. In this paper we study local properties of cost and potential functions in optimal transportation. We prove that in a proper normalization process, the cost function is uniformly smooth and converges locally smoothly to a quadratic cost x · y, while the potential function converges to a quadratic function. As applications we obtain the interior W2, p estimates and sharp C1, α estimates for the potentials, which satisfy a Monge–Ampère type equation. The W2, p estimate was previously proved by Caffarelli for the quadratic transport cost and the associated standard Monge–Ampère equation.


Quantum Ratchet In Two-Dimensional Semiconductors With Rashba Spin-Orbit Interaction, Yee Sin Ang, Zhongshui Ma, Chao Zhang Jan 2015

Quantum Ratchet In Two-Dimensional Semiconductors With Rashba Spin-Orbit Interaction, Yee Sin Ang, Zhongshui Ma, Chao Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

Ratchet is a device that produces direct current of particles when driven by an unbiased force. We demonstrate a simple scattering quantum ratchet based on an asymmetrical quantum tunneling effect in two-dimensional electron gas with Rashba spin-orbit interaction (R2DEG). We consider the tunneling of electrons across a square potential barrier sandwiched by interface scattering potentials of unequal strengths on its either sides. It is found that while the intra-spin tunneling probabilities remain unchanged, the inter-spin-subband tunneling probabilities of electrons crossing the barrier in one direction is unequal to that of the opposite direction. Hence, when the system is driven by ...


A Practical Path Planning Methodology For Wire And Arc Additive Manufacturing Of Thin-Walled Structures, Donghong Ding, Zengxi Pan, Dominic Cuiuri, Huijun Li Jan 2015

A Practical Path Planning Methodology For Wire And Arc Additive Manufacturing Of Thin-Walled Structures, Donghong Ding, Zengxi Pan, Dominic Cuiuri, Huijun Li

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a novel methodology to generate deposition paths for wire and arc additive manufacturing (WAAM). The medial axis transformation (MAT), which represents the skeleton of a given geometry, is firstly extracted to understand the geometry. Then a deposition path that is based on the MAT is efficiently generated. The resulting MAT-based path is able to entirely fill any given cross-sectional geometry without gaps. With the variation of step-over distance, material efficiency alters accordingly for both solid and thin-walled structures. It is found that thin-walled structures are more sensitive to step-over distance in terms of material efficiency. The optimal ...


Thermal Stability And Properties Of Deformation-Processed Cu-Fe In Situ Composites, Keming Liu, Zhengyi Jiang, Jingwei Zhao, Jin Zou, Lei Lu, Deping Lu Jan 2015

Thermal Stability And Properties Of Deformation-Processed Cu-Fe In Situ Composites, Keming Liu, Zhengyi Jiang, Jingwei Zhao, Jin Zou, Lei Lu, Deping Lu

Faculty of Engineering and Information Sciences - Papers: Part A

This paper investigated the thermal stability, tensile strength, and conductivity of deformation-processed Cu-14Fe in situ composites produced by thermo-mechanical processing. The thermal stability was analyzed using scanning electronic microscope and transmission electron microscope. The tensile strength and conductivity were evaluated using tensile-testing machine and micro-ohmmeter, respectively. The Fe fibers in the deformation-processed Cu-14Fe in situ composites undergo edge recession, longitudinal splitting, cylinderization, break-up, and spheroidization during the heat treatment. The Cu matrix experiences recovery, recrystallization, and precipitation phase transition. The tensile strength and conductivity first increase with increasing temperature of heat treatment, reach peak values at different temperatures, and then ...


Terahertz Spectroscopy Of 2,4-Dinitrotoluene Over A Wide Temperature Range (7−245 K), Lucia Lepodise, Josip Horvat, R A. Lewis Jan 2015

Terahertz Spectroscopy Of 2,4-Dinitrotoluene Over A Wide Temperature Range (7−245 K), Lucia Lepodise, Josip Horvat, R A. Lewis

Faculty of Engineering and Information Sciences - Papers: Part A

Previous THz spectroscopy of the TNT explosive precursor, 2,4-dinitrotoluene (DNT), has been restricted to room temperature (apart from one set of data at 11 K). Here, for the first time, we investigate the spectrum as the temperature is systematically varied, from 7 to 245 K. Many new features appear in the spectrum on cooling below room temperature. As well as the five absorption lines observed previously, we observe five additional lines. In addition, a new room-temperature line at 8.52 THz (281 cm−1) is observed. Six of the lines red-shift with temperature and four of them blue-shift. The ...


Convexity Estimates For Surfaces Moving By Curvature Functions, Ben Andrews, Mat Langford, James A. Mccoy Jan 2015

Convexity Estimates For Surfaces Moving By Curvature Functions, Ben Andrews, Mat Langford, James A. Mccoy

Faculty of Engineering and Information Sciences - Papers: Part A

We consider the evolution of compact surfaces by fully nonlinear, parabolic curvature ows for which the normal speed is given by a smooth, degree one homogeneous function of the principal curvatures of the evolving surface. Under no further restrictions on the speed function, we prove that initial surfaces on which the speed is positive become weakly convex at a singularity of the flow. This generalises the corresponding result [26] of Huisken and Sinestrari for the mean curvature ow to the largest possible class of degree one homogeneous surface flows.


Gap Phenomena For A Class Of Fourth-Order Geometric Differential Operators On Surfaces With Boundary, Glen Wheeler Jan 2015

Gap Phenomena For A Class Of Fourth-Order Geometric Differential Operators On Surfaces With Boundary, Glen Wheeler

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper we establish a gap phenomenon for immersed surfaces with arbitrary codimension, topology and boundaries that satisfy one of a family of systems of fourth-order anisotropic geometric partial differential equations. Examples include Willmore surfaces, stationary solitons for the surface diffusion flow, and biharmonic immersed surfaces in the sense of Chen. On the boundary we enforce either umbilic or flat boundary conditions: that the tracefree second fundamental form and its derivative or the full second fundamental form and its derivative vanish. For the umbilic boundary condition we prove that any surface with small L2-norm of the tracefree second fundamental ...


A New Approach For Classification And Characterization Of Voltage Dips And Swells Using 3d Polarization Ellipse Parameters, Mollah R. Alam, Kashem M. Muttaqi, Abdesselam Bouzerdoum Jan 2015

A New Approach For Classification And Characterization Of Voltage Dips And Swells Using 3d Polarization Ellipse Parameters, Mollah R. Alam, Kashem M. Muttaqi, Abdesselam Bouzerdoum

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a new method for classification and characterization of voltage dips and swells in electricity networks. The proposed method exploits unique signatures and parameters of three phase voltage signals extracted from the polarization ellipse in three-dimensional (3D) co-ordinates. Five ellipse parameters, which include azimuthal angle, elevation, tilt, semi-minor axis and semi-major axis, are used to classify and characterize voltage dips and swells. Seven types of voltage dips, which include a total of 19 groups of dips incorporating different kinds of balanced (three-phase dips) and unbalanced (single-phase or double-phase) dips, are identified and successfully classified using the 3D polarization ...


3d Printed Terahertz Diffraction Gratings And Lenses, A D. Squires, E Constable, R A. Lewis Jan 2015

3d Printed Terahertz Diffraction Gratings And Lenses, A D. Squires, E Constable, R A. Lewis

Faculty of Engineering and Information Sciences - Papers: Part A

3D printing opens up an inexpensive, rapid, and versatile path to the fabrication of optical elements suited to the terahertz regime. The transmission of the plastics used in 3D printers, while generally decreasing with frequency, is usable over the range 0.1-2 THz. We have designed, fabricated, and tested regular and blazed gratings and aspherical lenses for operation at terahertz frequencies. We find that the measured performance matches our theoretical predictions.