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Full-Text Articles in Engineering
Metamorphic Robustness Testing: Exposing Hidden Defects In Citation Statistics And Journal Impact Factors, Zhi Q. Zhou, T.H. Tse, Matt Witheridge
Metamorphic Robustness Testing: Exposing Hidden Defects In Citation Statistics And Journal Impact Factors, Zhi Q. Zhou, T.H. Tse, Matt Witheridge
Faculty of Engineering and Information Sciences - Papers: Part B
We propose a robustness testing approach for software systems that process large amounts of data. Our method usesmetamorphic relations to check software output for erroneous input in the absence of a tangible test oracle. We use this technique to testtwo major citation database systems: Scopus and the Web of Science. We report a surprising finding that the inclusion of hyphensin paper titles impedes citation counts, and that this is a result of the lack of robustness of the citation database systems in handlinghyphenated paper titles. Our results are valid for the entire literature as well as for individual fields such …
Vacancy-Type Defects Study On Ultra-Fine Grained Aluminium Processed By Severe Plastic Deformation, Li-Jun Su, C Lu, Guanyu Deng, A Kiet Tieu, L C. Zhang, P Guagliardo, S N. Samarin, J F. Williams
Vacancy-Type Defects Study On Ultra-Fine Grained Aluminium Processed By Severe Plastic Deformation, Li-Jun Su, C Lu, Guanyu Deng, A Kiet Tieu, L C. Zhang, P Guagliardo, S N. Samarin, J F. Williams
Faculty of Engineering and Information Sciences - Papers: Part A
Vacancy-type defects play an important role in the metal materials deformed by severe plastic deformation (SPD). The present work use positron annihilation lifetime spectroscopy (PALS) to test the vacancy-type defects in aluminium alloys processed by equal channel angular pressing (ECAP) and accumulative roll bonding (ARB). ECAP at room temperature and cryogenic temperature was conducted to AA1050 and ARB with 200 C preheating was conducted to AA1050 and AA6061 to produce laminated AA1050 sheets, AA6061 sheets and AA1050/AA6061 composites. High fraction of vacancy-type defects were detected in all the deformed samples. Vacancies associated with dislocations and bulk mono-vacancies have been identified …
Defects Induced Ferromagnetism In Plasma-Enabled Graphene Nanopetals, Zengji Yue, Donghan Seo, Kostya Ostrikov, Xiaolin Wang
Defects Induced Ferromagnetism In Plasma-Enabled Graphene Nanopetals, Zengji Yue, Donghan Seo, Kostya Ostrikov, Xiaolin Wang
Faculty of Engineering and Information Sciences - Papers: Part A
Ferromagnetism in graphene is fascinating, but it is still a big challenge for practical applications due to the weak magnetization. In order to enhance the magnetization, here, we design plasma-enabled graphene nanopetals with ultra-long defective edges of up to 105 m/g, ultra-dense lattice vacancies, and hydrogen chemisorptions. The designed graphene nanopetals display robust ferromagnetism with large saturation magnetization of up to 2 emu/g at 5 K and 1.2 emu/g at room temperatures. This work identifies the plasma-enabled graphene nanopetals as a promising candidate for graphene-based magnetic devices. 2014 AIP Publishing LLC.
Occurrence Of Surface Defects On Strips During Hot Rolling Process By Fem, Hai-Liang Yu, Kiet Tieu, Cheng Lu, Guan-Yu Deng, Xiang-Hua Liu
Occurrence Of Surface Defects On Strips During Hot Rolling Process By Fem, Hai-Liang Yu, Kiet Tieu, Cheng Lu, Guan-Yu Deng, Xiang-Hua Liu
Faculty of Engineering and Information Sciences - Papers: Part A
During a hot rolling process, surface defects on strips can severely affect the quality of the rolled product, particularly for two conditions: (1) there are initial defects on continuous casting slabs that propagate and/or are inherited from those on the surface of rolled steels from upstream rolling processes; and (2) there are no initial defects on continuous casting slabs, and they consequently appear on the surface of rolled steels due to improper rolling technologies. In this paper, the authors present a new 3D finite element model coupled with constrained node failure to understand better the initiation and growth of surface …
Simulation Of Defects In Micro-Deep Drawing Of An Aluminium Alloy Foil, Syamsul Hadi, Hai-Liang Yu, Kiet Tieu, Cheng Lu
Simulation Of Defects In Micro-Deep Drawing Of An Aluminium Alloy Foil, Syamsul Hadi, Hai-Liang Yu, Kiet Tieu, Cheng Lu
Faculty of Engineering and Information Sciences - Papers: Part A
Micro-forming refers to the application of conventional forming processes to manufacture products from ultra-thin sheet materials. While attempting to meet the increasing demand for cost-effective manufacturing of micro-formed components, it is very important to reduce the defects in the products. In this paper, we report a number of Finite Element (FE) simulations of the micro-deep drawing process with various sample thicknesses and eccentric distances. The simulations indicated that when the sample thickness is nearly equal to the gap between the plunger and the die, the sample is likely to develop fractures at the bottom corner. When the sample thickness is …
Solidification And The Δ/Γ Phase Transformation Of Steels In Relation To Casting Defects, Suk Chun Moon, Rian Dippenaar, Sang-Hyeon Lee
Solidification And The Δ/Γ Phase Transformation Of Steels In Relation To Casting Defects, Suk Chun Moon, Rian Dippenaar, Sang-Hyeon Lee
Faculty of Engineering and Information Sciences - Papers: Part A
Many advanced steels fall within the peritectic composition range, which are notoriously difficult to cast due to cracking and breakout problems in the continuous casting process especially at high casting speeds. In this study an attempt was made to obtain practical understanding of the solidification and the δ→γ phase transformation of various commercial steels using high-temperature laser-scanning confocal microscopy. Under rapid cooling conditions the transformation morphology showed a massive-type of transition rather than a classical diffusion-controlled transformation.