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2019

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Articles 25471 - 25500 of 31916

Full-Text Articles in Social and Behavioral Sciences

Reconstructing Directed Graphs From Generalized Gauge Actions On Their Toeplitz Algebras, Nathan D. Brownlowe, Marcelo Laca, David I. Robertson, Aidan Sims Jan 2019

Reconstructing Directed Graphs From Generalized Gauge Actions On Their Toeplitz Algebras, Nathan D. Brownlowe, Marcelo Laca, David I. Robertson, Aidan Sims

Faculty of Engineering and Information Sciences - Papers: Part B

We show how to reconstruct a finite directed graph E from its Toeplitz algebra, its gauge action, and the canonical finite-dimensional abelian subalgebra generated by the vertex projections. We also show that if E has no sinks, then we can recover E from its Toeplitz algebra and the generalized gauge action that has, for each vertex, an independent copy of the circle acting on the generators corresponding to edges emanating from that vertex. We show by example that it is not possible to recover E from its Toeplitz algebra and gauge action alone.

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Marginal Maximum Likelihood Estimation Of Conditional Autoregressive Models With Missing Data, Thomas F. Suesse, Andrew Zammit-Mangion Jan 2019

Marginal Maximum Likelihood Estimation Of Conditional Autoregressive Models With Missing Data, Thomas F. Suesse, Andrew Zammit-Mangion

Faculty of Engineering and Information Sciences - Papers: Part B

Maximum likelihood (ML) estimation of spatial autocorrelation models is well established for the case where each node in the graph is directly observed. When one or more nodes are not observed, the user has a variety of computational tools at her or his disposal ranging from the expectation-maximization algorithm, which has become a standard for missing‐data problems, to marginal likelihood estimation methods and to fully Bayesian approaches. In this article, we give a comprehensive overview of likelihood‐based computational frameworks for parameter estimation of the conditional autoregressive model, and we establish connections with several algorithms in the literature that are iterative …

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A 3d-Printed Omni-Purpose Soft Gripper, Charbel Tawk, Andrew Gillett, Marc In Het Panhuis, Geoffrey M. Spinks, Gursel Alici Jan 2019

A 3d-Printed Omni-Purpose Soft Gripper, Charbel Tawk, Andrew Gillett, Marc In Het Panhuis, Geoffrey M. Spinks, Gursel Alici

Faculty of Engineering and Information Sciences - Papers: Part B

Numerous soft grippers have been developed based on smart materials, pneumatic soft actuators, and underactuated compliant structures. In this article, we present a three-dimensional (3-D) printed omni-purpose soft gripper (OPSOG) that can grasp a wide variety of objects with different weights, sizes, shapes, textures, and stiffnesses. The soft gripper has a unique design that incorporates soft fingers and a suction cup that operate either separately or simultaneously to grasp specific objects. A bundle of 3-D-printable linear soft vacuum actuators (LSOVA) that generate a linear stroke upon activation is employed to drive the tendon-driven soft fingers. The support, fingers, suction cup, …

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Explicit Finite Difference Analysis Of An Unsteady Magnetohydrodynamics Heat And Mass Transfer Micropolar Fluid Flow In The Presence Of Radiation And Chemical Reaction Through A Vertical Porous Plate, R Biswas, M Mondal, Kazi Shanchia, Rubel Ahmed, S Samad, S Ahmmed Jan 2019

Explicit Finite Difference Analysis Of An Unsteady Magnetohydrodynamics Heat And Mass Transfer Micropolar Fluid Flow In The Presence Of Radiation And Chemical Reaction Through A Vertical Porous Plate, R Biswas, M Mondal, Kazi Shanchia, Rubel Ahmed, S Samad, S Ahmmed

Faculty of Engineering and Information Sciences - Papers: Part B

The investigation of this paper is undertaken to study of the problem of chemical reaction on MHD unsteady heat and mass transfer effects of micropolar fluid flow through a vertical plate. Different effects such as thermal diffusion, Soret and Dufour effects in the presence of radiation and chemical reaction are permitted in this observation. Firstly, the governing partial differential equations (PDEs) are transformed into a system of dimensionless coupled partial differential equations by the procedure of mathematical transformation. Then the obtained dimensionless equations are solved by explicit finite difference method (EFDM). Further, the momentum, temperature and concentration distributions are permitted …

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Measurement And Prediction Of Granite Damage Evolution In Deep Mine Seams Using Acoustic Emission, Sunwen Du, Guorui Feng, Zhixiong Li, T Sarkodie-Gyan, Jianmin Wang, Zhenjun Ma, Weihua Li Jan 2019

Measurement And Prediction Of Granite Damage Evolution In Deep Mine Seams Using Acoustic Emission, Sunwen Du, Guorui Feng, Zhixiong Li, T Sarkodie-Gyan, Jianmin Wang, Zhenjun Ma, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part B

With unceasing increase of mining depth and development intensity, mining disasters such as rock burst have been increasing frequently, which often result in catastrophic accidents. Therefore, it is imperative to accurately forecast underground disasters. Previous research has suggested that the combination of drill-hole pressure relief and acoustic emission (AE) monitoring serves as an effective measure method towards the forecasting and prevention of disastrous accidents. However, the AE evolution mechanism of underground rock damages remains a challenge; more specifically, the relationships among the drilling hole positions, depths and diameters, and the stress-strain and AE characteristics of the rocks are discussed little …

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Cooperative Secondary Voltage Control Of Static Converters In A Microgrid Using Model-Free Reinforcement Learning, Edward Smith, Duane A. Robinson, Ashish P. Agalgaonkar Jan 2019

Cooperative Secondary Voltage Control Of Static Converters In A Microgrid Using Model-Free Reinforcement Learning, Edward Smith, Duane A. Robinson, Ashish P. Agalgaonkar

Faculty of Engineering and Information Sciences - Papers: Part B

Agent-based secondary voltage regulation in an islanded MicroGrid is complicated by non-linear system dynamics, state couplings and uncertain communication network topology information. This paper proposes an off-policy learning algorithm for cooperative secondary voltage control which can synthesize an optimal feedback controller in real-time without knowledge of the system model. A simulation model has been developed using MATLAB/Simulink, which demonstrates a working controller. Results from the simulations are included, and practical considerations regarding implementation on a real system discussed.

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Error Compensation Method Of Large Size Steel Sheet Measurement Based On Control Field, Lei Geng, Fucai Yao, Wen Wang, Jiangtao Xi, Yaru Li Jan 2019

Error Compensation Method Of Large Size Steel Sheet Measurement Based On Control Field, Lei Geng, Fucai Yao, Wen Wang, Jiangtao Xi, Yaru Li

Faculty of Engineering and Information Sciences - Papers: Part B

Aiming at the problem of low accuracy of large size sheet edge, a method of sheet size error measurement based on control field is proposed. Firstly, an error compensation model of the measuring system based on control field is established by analyzing the causes of the errors of the measuring system. A grid standard plate is designed and the error distribution on the grid line is obtained by using the measurement results of the standard plate. Secondly, the error curve is established according to the distribution, and the trig function theorem is used to project the curve into the image …

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Towards A General Prediction System For The Primary Delay In Urban Railways, Jianqing Wu, Luping Zhou, Chen Cai, Fang Dong, Jun Shen, Geng Sun Jan 2019

Towards A General Prediction System For The Primary Delay In Urban Railways, Jianqing Wu, Luping Zhou, Chen Cai, Fang Dong, Jun Shen, Geng Sun

Faculty of Engineering and Information Sciences - Papers: Part B

Nowadays a large amount of data is collected from sensor devices across the cyber-physical networks. Accurate and reliable primary delay predictions are essential for rail operations management and planning. However, very few existing 'big data' methods meet the specific needs in railways. We propose a comprehensive and general data-driven Primary Delay Prediction System (PDPS) framework, which combines General Transit Feed Specification (GTFS), Critical Point Search (CPS), and deep learning models to leverage the data fusion. Based on this framework, we have also developed an open source data collection and processing tool that reduces the barrier to the use of the …

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Protecting The Visual Fidelity Of Machine Learning Datasets Using Qr Codes, Yang-Wai Chow, Willy Susilo, Jianfeng Wang, Richard Buckland, Joon Sang Baek, Jongkil Kim, Nan Li Jan 2019

Protecting The Visual Fidelity Of Machine Learning Datasets Using Qr Codes, Yang-Wai Chow, Willy Susilo, Jianfeng Wang, Richard Buckland, Joon Sang Baek, Jongkil Kim, Nan Li

Faculty of Engineering and Information Sciences - Papers: Part B

Machine learning is becoming increasingly popular in a variety of modern technology. However, research has demonstrated that machine learning models are vulnerable to adversarial examples in their inputs. Potential attacks include poisoning datasets by perturbing input samples to mislead a machine learning model into producing undesirable results. Such perturbations are often subtle and imperceptible from a human's perspective. This paper investigates two methods of verifying the visual fidelity of image based datasets by detecting perturbations made to the data using QR codes. In the first method, a verification string is stored for each image in a dataset. These verification strings …

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Numerical Analysis Of Behavior Of Glass Fiber-Reinforced Polymer Bar-Reinforced Concrete Beams Under Impact Loads, Zein Saleh, M Neaz Sheikh, Alex M. Remennikov, Abheek Basu Jan 2019

Numerical Analysis Of Behavior Of Glass Fiber-Reinforced Polymer Bar-Reinforced Concrete Beams Under Impact Loads, Zein Saleh, M Neaz Sheikh, Alex M. Remennikov, Abheek Basu

Faculty of Engineering and Information Sciences - Papers: Part B

This paper numerically investigates the behavior of glass fiber-reinforced polymer (GFRP) bar-reinforced concrete beams (GFRP-RC beams) under low-velocity impact loads. A finite element model has been developed and calibrated against the experimental investigation results of six GFRP-RC beams. The results of the numerical analysis have been found in very good agreement with the experimental investigation results. The finite element model captured the failure modes, crack profiles, midspan deflection, impact and reaction forces, and dynamic strain of the GFRP-RC beams. Moreover, a parametric study has been carried out to investigate the influence of the reinforcement ratio, compressive strength of concrete, drop …

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Bayesian Atmospheric Tomography For Detection And Quantification Of Methane Emissions: Application To Data From The 2015 Ginninderra Release Experiment, Laura Cartwright, Andrew Zammit-Mangion, Sangeeta Bhatia, Ivan Schroder, Frances A. Phillips, Trevor Coates, Karita Negandhi, Travis A. Naylor, Martin Kennedy, Steve Zegelin, Nick Wokker, Nicholas M. Deutscher, Andrew Feitz Jan 2019

Bayesian Atmospheric Tomography For Detection And Quantification Of Methane Emissions: Application To Data From The 2015 Ginninderra Release Experiment, Laura Cartwright, Andrew Zammit-Mangion, Sangeeta Bhatia, Ivan Schroder, Frances A. Phillips, Trevor Coates, Karita Negandhi, Travis A. Naylor, Martin Kennedy, Steve Zegelin, Nick Wokker, Nicholas M. Deutscher, Andrew Feitz

Faculty of Engineering and Information Sciences - Papers: Part B

Detection and quantification of greenhouse-gas emissions is important for both compliance and environment conservation. However, despite several decades of active research, it remains predominantly an open problem, largely due to model errors and assumptions that appear at each stage of the inversion processing chain. In 2015, a controlled-release experiment headed by Geoscience Australia was carried out at the Ginninderra Controlled Release Facility, and a variety of instruments and methods were employed for quantifying the release rates of methane and carbon dioxide from a point source. This paper proposes a fully Bayesian approach to atmospheric tomography for inferring the methane emission …

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Cyclic Transition Of Deformation In {1 2 3} <6 3 4> Single Crystal Processed By Accumulative Roll-Bonding, Hui Wang, Cheng Lu, Anh Kiet Tieu Jan 2019

Cyclic Transition Of Deformation In {1 2 3} <6 3 4> Single Crystal Processed By Accumulative Roll-Bonding, Hui Wang, Cheng Lu, Anh Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part B

In this study, the crystal plasticity finite element method model was used to study the deformation in a single crystal aluminium processed by accumulative roll-bonding (ARB). The predicted textures match well with the experimental observations up to nine cycles. The texture and slip activities in representative layers were investigated, and cyclic transition of them was observed. It was found that the thickness position change caused by cutting and stacking was a basic reason for the cyclic transition. Finally, the effect of shear deformation to this transition was discussed.

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Improving Positioning Accuracy Of The Mobile Laser Scanning In Gps-Denied Environments: An Experimental Case Study, W I. Liu, Zhixiong Li, Shuaishuai Sun, Reza Malekian, Zhenjun Ma, Weihua Li Jan 2019

Improving Positioning Accuracy Of The Mobile Laser Scanning In Gps-Denied Environments: An Experimental Case Study, W I. Liu, Zhixiong Li, Shuaishuai Sun, Reza Malekian, Zhenjun Ma, Weihua Li

Faculty of Engineering and Information Sciences - Papers: Part B

The positioning accuracy of the mobile laser scanning (MLS) system can reach the level of centimeter under the conditions where GPS works normally. However, in GPS-denied environments this accuracy can be reduced to the decimeter or even the meter level because the observation mode errors and the boresight alignment errors of MLS cannot be calibrated or corrected by the GPS signal. To bridge this research gap, this paper proposes a novel technique that appropriately incorporates the robust weight total least squares (RWTLS) and the full information maximum likelihood optimal estimation (FIMLOE) to improve the positioning accuracy of the MLS system …

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Finite Element Analysis Of Forward Slip In Micro Flexible Rolling Of Thin Aluminium Strips, Feijun Qu, Jianzhong Xu, Zhengyi Jiang Jan 2019

Finite Element Analysis Of Forward Slip In Micro Flexible Rolling Of Thin Aluminium Strips, Feijun Qu, Jianzhong Xu, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part B

This study delineates a novel finite element model to consider a pattern of process parameters affecting the forward slip in micro flexible rolling, which focuses on the thickness transition area of the rolled strip with thickness in the micrometre range. According to the strip marking method, the forward slip is obtained by comparison between the distance of the bumped ridges on the roll and that of the markings indented by the ridges, which not only simplifies the calculation process, but also maintains the accuracy as compared with theoretical estimates. The simulation results identify the qualitative and quantitative variations of forward …

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Effects Of Foot Orthoses On Dynamic Balance And Basketball Free-Throw Accuracy Before And After Physical Fatigue, Wing-Kai Lam, Winson Lee, Siu-On Ng, Yi Zheng Jan 2019

Effects Of Foot Orthoses On Dynamic Balance And Basketball Free-Throw Accuracy Before And After Physical Fatigue, Wing-Kai Lam, Winson Lee, Siu-On Ng, Yi Zheng

Faculty of Engineering and Information Sciences - Papers: Part B

While it is not uncommon for athletes to use foot orthoses to relieve pain and improve sports performance, little has been known about their effects on basketball performance. Free-throw basketball shooting is very important. However, fatigue deteriorates postural balance which might decrease free-throw shooting performance. This study investigated the effects of foot orthoses on dynamic balance and accuracy performance during free-throw shooting before and after physical fatigue was induced. Thirteen male recreational basketball players were tested with two foot orthoses (medial-arch support versus flat control) and fatigue conditions (before and after fatigue), when they performed standard free-throw shooting on a …

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Crystal Plasticity Modelling Of Microbands In A Rolled Aluminium Single Crystal, Hui Wang, Cheng Lu, Anh Kiet Tieu Jan 2019

Crystal Plasticity Modelling Of Microbands In A Rolled Aluminium Single Crystal, Hui Wang, Cheng Lu, Anh Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part B

In this study, an aluminium single crystal was deformed by roll-bonding, and the through-thickness texture and microstructure were characterized by electron backscattered diffraction (EBSD). Matrix bands and transition bands developed at the macro-scale, and microbands formed at the lower scale. Moreover, the crystal plasticity finite element method (CPFEM) was used to model the experimentally observed macro- and micro-subdivision. Matrix bands were captured in the Globalmodel that had a coarse mesh, and Submodel was adopted to predict microbands by refining the mesh. Two smaller regions of interest were selected from the Globalmodel and they were reconstructed in the Submodel. The Submodel …

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A Nanomechanical Analysis Of Deformation Characteristics Of 6h-Sic Using An Indenter And Abrasives In Different Fixed Methods, Jisheng Pan, Qiusheng Yan, Weihua Li, Xiaowei Zhang Jan 2019

A Nanomechanical Analysis Of Deformation Characteristics Of 6h-Sic Using An Indenter And Abrasives In Different Fixed Methods, Jisheng Pan, Qiusheng Yan, Weihua Li, Xiaowei Zhang

Faculty of Engineering and Information Sciences - Papers: Part B

The super-precise theory for machining single crystal SiC substrates with abrasives needs to be improved for its chemical stability, extremely hard and brittle. A Berkovich indenter was used to carry out a systematic static stiffness indentation experiments on single crystal 6H-SiC substrates, and then these substrates were machined by utilizing fixed, free, and semi-fixed abrasives, and the nanomechanical characteristics and material removal mechanisms using abrasives in different fixed methods were analyzed theoretically. The results indicated that the hardness of C faces and Si faces of single crystal 6H-SiC under 500 mN load were 38.596 Gpa and 36.246 Gpa respectively, and …

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A Derivative-Free Vu-Algorithm For Convex Finite-Max Problems, Warren L. Hare, Chayne Planiden, Claudia Sagastizabal Jan 2019

A Derivative-Free Vu-Algorithm For Convex Finite-Max Problems, Warren L. Hare, Chayne Planiden, Claudia Sagastizabal

Faculty of Engineering and Information Sciences - Papers: Part B

The VU-algorithm is a superlinearly convergent method for minimizing nonsmooth, convex functions. At each iteration, the algorithm works with a certain V-space and its orthogonal u-space, such that the nonsmoothness of the objective function is concentrated on its projection onto the V-space, and on the U-space the projection is smooth. This structure allows for an alternation between a Newton-like step where the function is smooth, and a proximal-point step that is used to find iterates with promising VU-decompositions. We establish a derivative-free variant of the VU-algorithm for convex finite-max objective functions. We show global …

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Thermionic Enhanced Heat Transfer In Electronic Devices Based On 3d Dirac Materials, Sunchao Huang, R A. Lewis, C Zhang Jan 2019

Thermionic Enhanced Heat Transfer In Electronic Devices Based On 3d Dirac Materials, Sunchao Huang, R A. Lewis, C Zhang

Faculty of Engineering and Information Sciences - Papers: Part B

We calculate the heat transfer from electronic devices based on three-dimensional Dirac materials without and with thermionic cooling. Without thermionic cooling, the internal temperature of the devices is at best equal to and usually higher than the temperature of the surrounding environment. However, when thermionic cooling is employed to transport heat, the internal temperature can be considerably lower than the environmental temperature. In the proposed thermionic cooling process, the energy efficiency can be as high as 75% of the Carnot efficiency.

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Full-Duplex Ofdm Relaying Systems With Energy Harvesting In Multipath Fading Channels, Jiaman Li, Le Chung Tran, Farzad Safaei Jan 2019

Full-Duplex Ofdm Relaying Systems With Energy Harvesting In Multipath Fading Channels, Jiaman Li, Le Chung Tran, Farzad Safaei

Faculty of Engineering and Information Sciences - Papers: Part B

In this paper, the performance of in-band fullduplex OFDM relaying systems with energy-harvesting and selfinterference cancellation in the polarization domain is analyzed. Specifically, we use the time switching-based relaying protocol to implement energy harvesting. The harvested energy is used by the relay to forward the transmitted information from the source. To cancel the self-interference, the polarization-enabled digital self-interference cancellation scheme is deployed at the relay. Our simulation results show that the full-duplex OFDM energy harvesting relaying system almost doubles the throughput, while maintaining the same bit error performance by a modest increase in the signal-to-noise ratio compared to the half-duplex …

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A Study On The Local Corrosion Behavior And Mechanism Of Electroless Ni-P Coatings Under Flow By Using A Wire Beam Electrode, Yi-Rong Tang, Qin-Ying Wang, Rui Pei, Yu-Chen Xi, Li-Jin Dong, Shu-Lin Bai, Shanhong Wan Jan 2019

A Study On The Local Corrosion Behavior And Mechanism Of Electroless Ni-P Coatings Under Flow By Using A Wire Beam Electrode, Yi-Rong Tang, Qin-Ying Wang, Rui Pei, Yu-Chen Xi, Li-Jin Dong, Shu-Lin Bai, Shanhong Wan

Faculty of Engineering and Information Sciences - Papers: Part B

The local corrosion behavior and mechanism of Ni-P coatings in a 3.5 wt% sodium chloride solution with different flow speeds (0 m s-1, 0.5 m s-1, 1 m s-1) were investigated through a wire beam electrode (WBE) with morphological, elemental and electrochemical analyses as well as numerical simulations. It was found that the microstructure of the Ni-P coating was in the shape of broccoli and possessed satisfactory compactness and uniformity. The numerical simulations showed that the speed increased and the static pressure decreased at the local area. Combined with WBE, it was found that …

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A Semianalytical Formula For European Options Under A Hybrid Heston-Cox-Ingersoll-Ross Model With Regime Switching, Xinjiang He, Wenting Chen Jan 2019

A Semianalytical Formula For European Options Under A Hybrid Heston-Cox-Ingersoll-Ross Model With Regime Switching, Xinjiang He, Wenting Chen

Faculty of Engineering and Information Sciences - Papers: Part B

In this paper, we consider the pricing of European options under a regime-switching Heston-Cox-Ingersoll-Ross (CIR) hybrid model, where the mean-reversion levels of both the stochastic volatility and interest rate are assumed to change among different states. Albeit difficult, we have still managed to derive an semianalytical pricing formula for European options after the generalized moment generating function of this particular model is worked out. Numerical experiments are also carried out to demonstrate the accuracy of the newly derived formula as well as the influence of the introduction of the regime-switching mechanics on option prices. Finally, through a preliminary empirical study, …

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In-Situ Cu Coating On Steel Surface After Oxidizing At High Temperature, Na Li, Ruizhi Jia, Hongmei Zhang, Wei Sha, Yan Li, Zhengyi Jiang Jan 2019

In-Situ Cu Coating On Steel Surface After Oxidizing At High Temperature, Na Li, Ruizhi Jia, Hongmei Zhang, Wei Sha, Yan Li, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part B

Almost all copper in scrap steel is recovered, so research on copper-bearing steel has profound practical significance. The surface enrichment of copper occurs in all copper-bearing steels studied in this paper after being heated at high temperature. In-situ oxidation-induced copper coatings were discovered on the descaled copper-bearing steels after heating at around 1150 °C for 2 h in air. Scattered copper precipitates in or under rust after heating at a lower temperature. A new concept was created using in-situ composites prepared by direct oxidation of matrix, and there was no bonding problem found between the coating and the matrix. The …

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Mechanical Properties Of Aluminium Metal Matrix Nanocomposites Manufactured By Assisted-Flake Powder Thixoforming Process, Saud Almotairy, Alireza Fadavi Boostani, M Hassani, Dongbin Wei, Zhengyi Jiang Jan 2019

Mechanical Properties Of Aluminium Metal Matrix Nanocomposites Manufactured By Assisted-Flake Powder Thixoforming Process, Saud Almotairy, Alireza Fadavi Boostani, M Hassani, Dongbin Wei, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part B

This study discusses the superior effect of thixoforming process on enhancing the tensile properties of aluminium matrix composite produced using flake metallurgy route. The flake metallurgy process was utilised to manufacture aluminium matrix composites followed by thixoforming process. Microstructural investigations carried out using transmission electron microscope have shown the synergic effect of thixoforming process on rendering uniform distribution of SiC nanoparticles associated with lower porosity content. X-ray diffraction characterisations have revealed the promising effect of uniform dispersion of SiC nanoparticles on restricting the grain growth of aluminium matrix within nanoscale regime (90 nm) even at high semi-solid thixoforming temperatures (575 …

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A Crystal Plasticity Fem Investigation Of A Cu Single Crystal Processed By Accumulative Roll-Bonding, Hui Wang, Cheng Lu, Anh Kiet Tieu Jan 2019

A Crystal Plasticity Fem Investigation Of A Cu Single Crystal Processed By Accumulative Roll-Bonding, Hui Wang, Cheng Lu, Anh Kiet Tieu

Faculty of Engineering and Information Sciences - Papers: Part B

In this study, texture modelling of a copper single crystal processed by accumulative roll-bonding (ARB) was conducted for the first time. A crystal plasticity finite element method (CPFEM) model was developed, and the predicated textures were validated by the experimental observations conducted by another research group. A heterogeneous through-thickness deformation was revealed. Two types of matrix bands formed through the thickness after the first ARB cycle, and different crystal rotation, slip system activation, and shear strain evolved in matrix bands. Due to the cutting, stacking and roll-bonding involved in ARB, transition of deformation behaviours has been found after a position …

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Flexible Surface Electrodes Targeting Biopotential Signals From Forearm Muscles For Control Of Prosthetic Hands: Part 1 - Characterisation Of Semg Electrodes, Siobhan O'Brien, Thomas Searle, Gursel Alici Jan 2019

Flexible Surface Electrodes Targeting Biopotential Signals From Forearm Muscles For Control Of Prosthetic Hands: Part 1 - Characterisation Of Semg Electrodes, Siobhan O'Brien, Thomas Searle, Gursel Alici

Faculty of Engineering and Information Sciences - Papers: Part B

This study is Part 1 of two studies which investigate the use of various flexible surface sensors as an alternative to the gold standard Ag/AgCl surface electromyography (sEMG) electrodes in identifying movement intention from a user during common hand gestures. Three conductive textiles, two commercial conductive elastomers and one E-skin elastomer produced on site were tested as biopotential electrodes to establish the efficacy of each in gathering movement intention from the human brain at the level of the muscle. Testing was performed in vivo on two participants across three hand gestures, with results demonstrating that sEMG electrodes made from a …

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3d Printable Vacuum-Powered Soft Linear Actuators, Charbel Tawk, Geoffrey M. Spinks, Marc In Het Panhuis, Gursel Alici Jan 2019

3d Printable Vacuum-Powered Soft Linear Actuators, Charbel Tawk, Geoffrey M. Spinks, Marc In Het Panhuis, Gursel Alici

Faculty of Engineering and Information Sciences - Papers: Part B

Soft robots which are made of highly deformable materials are ideal to operate in unstructured environments and to interact safely with humans. This work presents directly 3D printed linear soft vacuum actuators (LSOVA), that are manufactured in a single step without requiring any post-processing and support material, using a low-cost and open-source fused deposition modeling 3D printer. LSOVA have multiple advantages such as high bandwidths (~6.49Hz), high output forces (~27N) and long lifetimes (~21,500 cycles). Finite element models and analytical models are developed to accurately predict the performance of LSOVA in terms of blocked force and linear stroke. The LSOVAs …

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Secondary Students' Ideas About Scientific Concepts Underlying Climate Change, Lorna E. Jarrett, George J. Takacs Jan 2019

Secondary Students' Ideas About Scientific Concepts Underlying Climate Change, Lorna E. Jarrett, George J. Takacs

Faculty of Engineering and Information Sciences - Papers: Part B

We present ideas about concepts underlying climate change, held by students in years 9 and 10. Misconceptions about climate change are common among students, and may be due to misconceptions about underlying concepts. To investigate this, we developed the Climate Change Concept Inventory (CCCI), and trialed it with 229 students; corroborating findings through focus group interviews. Our interview method and data analysis methods are described. Findings included overestimation of human contributions to atmospheric carbon inputs, ultra violet radiation in sunlight, and greenhouse gases in the atmosphere. Students were unaware that CO2 dissolves in water, and of the role of oceans …

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Evaluation Of Different B-Values In Dwi And 1h Mrs For Pancreatic Cancer And Pancreatitis: A Rabbit Model, Liguo Hao, Lijie Liu, Xin Meng, Guanghao Yu, Enbang Li, Hongqian Gu Jan 2019

Evaluation Of Different B-Values In Dwi And 1h Mrs For Pancreatic Cancer And Pancreatitis: A Rabbit Model, Liguo Hao, Lijie Liu, Xin Meng, Guanghao Yu, Enbang Li, Hongqian Gu

Faculty of Engineering and Information Sciences - Papers: Part B

Pancreatic cancer is a common malignant tumor with high incidence of metastasis. Currently, there is no absolute standard for the choice of b-value for diffusion-weighted imaging (DWI) for pancreatic cancer. The b-value is rarely reported in animal model study, especially in pancreatic cancer/mass pancreatitis rabbit models. The authors' aim was to determine the different b-values to differentiate the diagnosis of pancreatic cancer and mass pancreatitis in rabbit models using DWI. When comparing the effect of different b-values in diagnostic process, the pathological results could be regarded as the gold standard. In this research, 30 healthy New Zealand rabbits were selected …

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On Matrix Completion-Based Channel Estimators For Massive Mimo Systems, Mingjun Ding, Xiaodong Yang, Rui Hu, Zhitao Xiao, Jun Tong, Jiangtao Xi Jan 2019

On Matrix Completion-Based Channel Estimators For Massive Mimo Systems, Mingjun Ding, Xiaodong Yang, Rui Hu, Zhitao Xiao, Jun Tong, Jiangtao Xi

Faculty of Engineering and Information Sciences - Papers: Part B

Large-scale symmetric arrays such as uniform linear arrays (ULA) have been widely used in wireless communications for improving spectrum efficiency and reliability. Channel state information (CSI) is critical for optimizing massive multiple-input multiple-output(MIMO)-based wireless communication systems. The acquisition of CSI for massive MIMO faces challenges such as training shortage and high computational complexity. For millimeter wave MIMO systems, the low-rankness of the channel can be utilized to address the challenge of training shortage. In this paper, we compared several channel estimation schemes based on matrix completion (MC) for symmetrical arrays. Performance and computational complexity are discussed and compared. By comparing …

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