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Science and Technology Studies Commons

Open Access. Powered by Scholars. Published by Universities.®

2015

Effect

University of Wollongong

Articles 1 - 9 of 9

Full-Text Articles in Science and Technology Studies

The Bulk-Edge Correspondence For The Quantum Hall Effect In Kasparov Theory, Christopher J. Bourne, Alan L. Carey, Adam C. Rennie Jan 2015

The Bulk-Edge Correspondence For The Quantum Hall Effect In Kasparov Theory, Christopher J. Bourne, Alan L. Carey, Adam C. Rennie

Faculty of Engineering and Information Sciences - Papers: Part A

We prove the bulk-edge correspondence in K-theory for the quantum Hall effect by constructing an unbounded Kasparov module from a short exact sequence that links the bulk and boundary algebras. This approach allows us to represent bulk topological invariants explicitly as a Kasparov product of boundary invariants with the extension class linking the algebras. This paper focuses on the example of the discrete integer quantum Hall effect, though our general method potentially has much wider applications.


Grain Size Effect Of Thickness/Average Grain Size On Mechanical Behaviour, Fracture Mechanism And Constitutive Model For Phosphor Bronze Foil, Zhi Fang, Zhengyi Jiang, Xiaogang Wang, Cunlong Zhou, Dongbin Wei, Xianghua Liu Jan 2015

Grain Size Effect Of Thickness/Average Grain Size On Mechanical Behaviour, Fracture Mechanism And Constitutive Model For Phosphor Bronze Foil, Zhi Fang, Zhengyi Jiang, Xiaogang Wang, Cunlong Zhou, Dongbin Wei, Xianghua Liu

Faculty of Engineering and Information Sciences - Papers: Part A

Size effects play a significant role in microforming process, and any dimensional change can have a great impact on materials' mechanical properties. In this paper, the size effects on deformation behaviour and fracture of phosphor foil were investigated in the form of grain size effect: the ratio of materials' thickness (T) to average grain size (D) by micro tensile tests. The ratio was designed to be closed to but larger than, less than and equal to 1, respectively. The results show that the amount of plastic deformation decreases with the decrease of the ratio of T/D, which indicates that ...


Effect Of Temperature On Microstructure And Deformation Mechanism Of Fe-30mn-3si-4al Twip Steel At Strain Rate Of 700 S-1, Zhiping Xiong, Xue-Ping Ren, Jian Shu, Zhe-Lei Wang, Wei-Ping Bao, Shu-Xia Li Jan 2015

Effect Of Temperature On Microstructure And Deformation Mechanism Of Fe-30mn-3si-4al Twip Steel At Strain Rate Of 700 S-1, Zhiping Xiong, Xue-Ping Ren, Jian Shu, Zhe-Lei Wang, Wei-Ping Bao, Shu-Xia Li

Faculty of Engineering and Information Sciences - Papers: Part A

As twinning-induced plasticity (TWIP) steel is one potential material for shaped charge liner due to the combination of high strength and high plasticity, deformation mechanism at high strain rate and high temperature is required to study. Compression experiments of Fe-30Mn-3Si-4Al TWIP steel were conducted using a Gleeble-1500 thermal simulation machine and a split-Hopkinson pressure bar (SHPB) between 298 and 1073 K at strain rates of 10-3 and 700 s-1, respectively. Microstructures were observed using optical microscopy (OM) and transmission electron microscopy (TEM). Results show that flow stress and densities of deformation twins and dislocations decrease with increasing deformation temperature at ...


The Effect Of Geometry And Material Properties On The Performance Of A Small Hydraulic Mckibben Muscle System, Danial Sangian, Sina Naficy, Geoffrey M. Spinks, Bertrand Tondu Jan 2015

The Effect Of Geometry And Material Properties On The Performance Of A Small Hydraulic Mckibben Muscle System, Danial Sangian, Sina Naficy, Geoffrey M. Spinks, Bertrand Tondu

Faculty of Engineering and Information Sciences - Papers: Part A

Fluidic McKibben artificial muscles are one of the most popular biomimetic actuators, showing similar static and dynamic performance to skeletal muscles. In particular, their pneumatic version offers high-generated force, high speed and high strain in comparison to other actuators. This paper investigates the development of a small-size, fully enclosed, hydraulic McKibben muscle powered by a low voltage pump. Hydraulic McKibben muscles with an outside diameter of 6 mm and a length ranging from 35 mm to 80 mm were investigated. These muscles are able to generate forces up to 26 N, strains up to 23%, power to mass of 30 ...


Effect Of Mesh On Springback In 3d Finite Element Analysis Of Flexible Microrolling, Feijun Qu, Zhengyi Jiang, Haina Lu Jan 2015

Effect Of Mesh On Springback In 3d Finite Element Analysis Of Flexible Microrolling, Feijun Qu, Zhengyi Jiang, Haina Lu

Faculty of Engineering and Information Sciences - Papers: Part A

In flexible microrolling, springback in thickness direction is a critical indicator to determine the forming quality. Accurate prediction of springback is one of the significant aspects in the finite element analysis of flexible microrolling. Meshing is a step of great importance in finite element analysis of manufacturing process as it directly determines the accuracy of the FEA results as well as the requested computational time. This paper presents a numerical study on revealing the mesh effects on the accuracy of springback estimation utilising ABAQUS/Standard for modelling and analyses. Two types of meshes with six mesh sizes for each mesh ...


Effect Of Pre-Quenching Process On Microstructure And Mechanical Properties In A Nb-Microalloyed Low Carbon Q-P Steel, Jun Zhang, Hua Ding, Jingwei Zhao Jan 2015

Effect Of Pre-Quenching Process On Microstructure And Mechanical Properties In A Nb-Microalloyed Low Carbon Q-P Steel, Jun Zhang, Hua Ding, Jingwei Zhao

Faculty of Engineering and Information Sciences - Papers: Part A

A refined microstructure consisting of martensite and retained austenite at room temperature has been produced in a Nb-microalloyed low carbon Si-Mn steel by a novel heat-treatment, pre-quenching prior to quenching and partitioning processes (Q&Q-P). The results showed that compared with the conventional quenching and partitioning steel the mechanical properties of steel obtained by the novel treatment have been significantly improved, with a good combination of ultimate tensile strength (1000MPa) and total elongation (above 30%). Meanwhile, the volume fraction of retained austenite has been increased. It was found that the improvement of mechanical properties was mainly attributed to the enhanced ...


Effect Of Extreme Pressure Additives On The Deformation Behavior Of Oxide Scale During The Hot Rolling Of Ferritic Stainless Steel Strips, Liang Hao, Zhengyi Jiang, Xiawei Cheng, Jingwei Zhao, Dongbin Wei, Laizhu Jiang, Suzhen Luo, Ming Luo, Li Ma Jan 2015

Effect Of Extreme Pressure Additives On The Deformation Behavior Of Oxide Scale During The Hot Rolling Of Ferritic Stainless Steel Strips, Liang Hao, Zhengyi Jiang, Xiawei Cheng, Jingwei Zhao, Dongbin Wei, Laizhu Jiang, Suzhen Luo, Ming Luo, Li Ma

Faculty of Engineering and Information Sciences - Papers: Part A

High-speed steel (HSS) materials are universally used as work rolls for the hot rolling of stainless steels. Their use has increased the output of the rolling mill and decreased roll material consumption and grinding. Sticking defects often occur, however, during the hot rolling process. In this article, extreme pressure (EP) additives were dropped on the HSS samples at high temperature. Zinc dialkyl dithiophosphate (ZDDP) was chosen as the most effective EP additive by scratch tests on the HSS samples. In order to determine the optimum proportion of ZDDP in the lubricant, two reduction rates were tested on a Hille 100 ...


The Effect Of Nb On The Continuous Cooling Transformation Curves Of Ultra-Thin Strip Castrip© Steels, Kristin R. Carpenter, Chris R. Killmore Jan 2015

The Effect Of Nb On The Continuous Cooling Transformation Curves Of Ultra-Thin Strip Castrip© Steels, Kristin R. Carpenter, Chris R. Killmore

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of Nb on the hardenability of ultra-thin cast strip (UCS) steels produced via the unique regime of rapid solidification, large austenite grain size, and inclusion engineering of the CASTRIP© process was investigated. Continuous cooling transformation (CCT) diagrams were constructed for 0, 0.014, 0.024, 0.04, 0.06 and 0.08 wt% Nb containing UCS steels. Phase nomenclature for the identification of lower transformation product in low carbon steels was reviewed. Even a small addition of 0.014 wt% Nb showed a potent effect on hardenability, shifting the ferrite C-curve to the right and expanding the bainitic ...


Improved Correction For The Tissue Fraction Effect In Lung Pet/Ct Imaging, Beverley F. Holman, Vesna Cuplov, Lynn Millner, Brian F. Hutton, Toby M. Maher, Ashley M. Groves, Kris Thielemans Jan 2015

Improved Correction For The Tissue Fraction Effect In Lung Pet/Ct Imaging, Beverley F. Holman, Vesna Cuplov, Lynn Millner, Brian F. Hutton, Toby M. Maher, Ashley M. Groves, Kris Thielemans

Faculty of Engineering and Information Sciences - Papers: Part A

Recently, there has been an increased interest in imaging different pulmonary disorders using PET techniques. Previous work has shown, for static PET/CT, that air content in the lung influences reconstructed image values and that it is vital to correct for this 'tissue fraction effect' (TFE). In this paper, we extend this work to include the blood component and also investigate the TFE in dynamic imaging. CT imaging and PET kinetic modelling are used to determine fractional air and blood voxel volumes in six patients with idiopathic pulmonary fibrosis. These values are used to illustrate best and worst case scenarios ...