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Articles 991 - 1020 of 14367

Full-Text Articles in Social and Behavioral Sciences

Label Enhanced And Patch Based Deep Learning For Phase Retrieval From Single Frame Fringe Pattern In Fringe Projection 3d Measurement, Jiashuo Shi, Xinjun Zhu, Hongyi Wang, Limei Song, Qinghua Guo Jan 2019

Label Enhanced And Patch Based Deep Learning For Phase Retrieval From Single Frame Fringe Pattern In Fringe Projection 3d Measurement, Jiashuo Shi, Xinjun Zhu, Hongyi Wang, Limei Song, Qinghua Guo

Faculty of Engineering and Information Sciences - Papers: Part B

We propose a label enhanced and patch based deep learning phase retrieval approach which can achieve fast and accurate phase retrieval using only several fringe patterns as training dataset. To the best of our knowledge, it is the first time that the advantages of the label enhancement and patch strategy for deep learning based phase retrieval are demonstrated in fringe projection. In the proposed method, the enhanced labeled data in training dataset is designed to learn the mapping between the input fringe pattern and the output enhanced fringe part of the deep neural network (DNN). Moreover, the training data is …

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Modelling Of The Silicon-On-Insulator Microdosimeter Response Within The International Space Station For Astronauts' Radiation Protection, Stefania Peracchi, James Vohradsky, Susanna Guatelli, David Bolst, Linh T. Tran, Dale A. Prokopovich, Anatoly B. Rosenfeld Jan 2019

Modelling Of The Silicon-On-Insulator Microdosimeter Response Within The International Space Station For Astronauts' Radiation Protection, Stefania Peracchi, James Vohradsky, Susanna Guatelli, David Bolst, Linh T. Tran, Dale A. Prokopovich, Anatoly B. Rosenfeld

Faculty of Engineering and Information Sciences - Papers: Part B

Astronauts are exposed to high-energy cosmic radiation which may have harmful health effects. At the altitude of the International Space Station (ISS), the main radiation sources are Galactic Cosmic Rays (GCRs), Solar Particle Events (SPEs) and trapped protons of the Van Allen Belts. The radiation field mainly consists of protons, helium nuclei and heavy ions with energies up to hundreds of GeV/n. A powerful approach to determine the effect of space radiation on astronauts is microdosimetry. The Centre for Medical Radiation Physics is active in the development of Silicon-On-Insulator (SOI) microdosimeters, as an alternative to Tissue Equivalent Proportional Counters (TEPCs) …

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Degradation Of Diclofenac, Trimethoprim, Carbamazepine, And Sulfamethoxazole By Laccase From Trametes Versicolor: Transformation Products And Toxicity Of Treated Effluent, Sultan Alharbi, Long D. Nghiem, Jason P. Van De Merwe, Frederic Leusch, Muhammad Bilal Asif, Faisal I. Hai, William E. Price Jan 2019

Degradation Of Diclofenac, Trimethoprim, Carbamazepine, And Sulfamethoxazole By Laccase From Trametes Versicolor: Transformation Products And Toxicity Of Treated Effluent, Sultan Alharbi, Long D. Nghiem, Jason P. Van De Merwe, Frederic Leusch, Muhammad Bilal Asif, Faisal I. Hai, William E. Price

Faculty of Engineering and Information Sciences - Papers: Part B

The degradation of diclofenac (DCF), trimethoprim (TMP), carbamazepine (CBZ), and sulfamethoxazole (SMX) by laccase from Trametes versicolor was investigated. Experiments were conducted using the pharmaceuticals individually, or as a mixture at different initial concentrations (1.25 and 5 mg/L each). The initial enzymatic activity of all the treated samples was around 430-460 U (DMP) /L. The removal of the four selected pharmaceuticals tested individually was more effective than when tested in mixtures under the same conditions. For example, 5 mg DCF/L was completely removed to below its detection limit (1 µg/L) within 8 h in the individual experiment vs. after 24 …

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A New Shock-Wave Test Apparatus For Liquid Co2 Blasting And Measurement Analysis, Ying Chen, Hongwei Zhang, Zhijie Zhu, Ting X. Ren, Chen Cao, Feng Zhu, Yunpeng Li Jan 2019

A New Shock-Wave Test Apparatus For Liquid Co2 Blasting And Measurement Analysis, Ying Chen, Hongwei Zhang, Zhijie Zhu, Ting X. Ren, Chen Cao, Feng Zhu, Yunpeng Li

Faculty of Engineering and Information Sciences - Papers: Part B

Liquid CO 2 blasting of coal or rock body technology is widely used for improving permeability, pressure relief, cutting proof, and roadway development. Due to the lack of proper apparatus for blasting measurement, the determination of blasting parameters is often not under scientific basis. A newly designed experimental apparatus is developed to monitor shock-wave pressure of liquid CO 2 blasting. The apparatus mainly consists of testing tube and base bracket. The testing tube is fixed on the base bracket by fixed ring. The base bracket is fixed to the ground by expansion bolts to ensure the stability of the apparatus …

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A Theoretical Model For Total Suction Effects By Tree Roots, Udeshini Pathirage, Buddhima Indraratna, Muditha Pallewattha, Ana Heitor Jan 2019

A Theoretical Model For Total Suction Effects By Tree Roots, Udeshini Pathirage, Buddhima Indraratna, Muditha Pallewattha, Ana Heitor

Faculty of Engineering and Information Sciences - Papers: Part B

Strengthening soft and weak soil by way of root reinforcement is a well-known strategy that is adopted worldwide. In Australia, native gum trees remain evergreen throughout the year and have been utilised to stabilise transportation corridors by way of reinforcement provided by the roots and the suction generated within the root domain as a function of evapotranspiration through the canopy. A mature gum tree can induce a missive total suction pressure exceeding 30MPa through its root water and solute uptake in terms of matric plus osmotic suction. This cumulative effect of matric and osmotic suctions contributes to the overall shear …

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Performance Analysis Of Heat Pump Dryer With Unit-Room In Cold Climate Regions, Ya Yuan, Wenye Lin, Xiang Mao, Weizhao Li, Luwei Yang, Juan Wei, Bo Xiao Jan 2019

Performance Analysis Of Heat Pump Dryer With Unit-Room In Cold Climate Regions, Ya Yuan, Wenye Lin, Xiang Mao, Weizhao Li, Luwei Yang, Juan Wei, Bo Xiao

Faculty of Engineering and Information Sciences - Papers: Part B

This study presents the development and evaluation of a novel partially open-loop heat pump dryer with a unit-room (HPDU). The unit-room was designed to enable the ambient air to be mixed with the return air, thereby reducing the influence of the ambient air on the system performance, while maintaining a high system thermal efficiency. A modelling system for the HPDU was developed and validated based on a real-scale experimental study. By using the modelling system, the system characteristics under different ambient conditions and bypass factors were analyzed. The energy benefit of the proposed HPDU was quantified through a comparative study …

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Analytically Pricing Credit Default Swaps Under A Regime-Switching Model, Wenting Chen, Xinjiang He, Xinzi Qiu Jan 2019

Analytically Pricing Credit Default Swaps Under A Regime-Switching Model, Wenting Chen, Xinjiang He, Xinzi Qiu

Faculty of Engineering and Information Sciences - Papers: Part B

In this paper, we consider the valuation of a CDS (credit default swap) contract when the reference asset is assumed to follow a regime-switching model with the volatility allowed to jump among different states. Our motivation originates from empirical evidence demonstrating the existence of regime-switching in real markets. The default probability is analytically derived first, based on which a closed-form formula for the CDS price is obtained so that it can be easily implemented for practical purposes. Finally, numerical experiments are carried out to show quantitatively some properties of the CDS price under the regime-switching model.

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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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