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Full-Text Articles in Science and Technology Studies
A Round-Robin Test With Thermal Simulation Of The Welding Haz To Draw Cct Diagrams: A Need For Harmonized Procedures And Microconstituent Terminologies, Americo Scotti, Huijun Li, Rosa M. Miranda
A Round-Robin Test With Thermal Simulation Of The Welding Haz To Draw Cct Diagrams: A Need For Harmonized Procedures And Microconstituent Terminologies, Americo Scotti, Huijun Li, Rosa M. Miranda
Faculty of Engineering and Information Sciences - Papers: Part A
Thermal simulations of heat affected zone (HAZ) have been widely used. This is an economic expedite process for phase transformation evaluations in steels when subjected to weld thermal cycles as well as to draw continuous cooling transformation (CCT) diagrams. Different approaches for the simulation and parameter settings have been used by several researchers, yet leading to not always even results. Thus, it was proposed a round-robin test trial performed by different laboratories, aiming to evidence potential sources of error or inadequacy of the approaches. A High Strength Low Alloy (HSLA) steel was used as a case study. Despite the limited …
A Combined Experimental And Simulation Method For Appraising The Energy Performance Of Green Roofs In Ningbo's Chinese Climate, Georgios Kokogiannakis, Jo Darkwa, Kate Yuan
A Combined Experimental And Simulation Method For Appraising The Energy Performance Of Green Roofs In Ningbo's Chinese Climate, Georgios Kokogiannakis, Jo Darkwa, Kate Yuan
Faculty of Engineering and Information Sciences - Papers: Part A
A passive means of lowering the energy demand of buildings is the application of green roofs. The complexity between heat and moisture exchanges in green roof layers and the large variations of green roof types make the need for experimental or simulation assessments necessary for quantifying the energy benefits from green roofs. The current treatment of green roofs in simulation programs is either over-simplistic, for example by ignoring heat and moisture exchanges such as evapotranspiration, or the more advanced models have limitations and require inputs that are rarely available in practice. In this paper a combination of experimental and modelling …
Optimisation Of Size-Controllable Centroidal Voronoi Tessellation For Fem Simulation Of Micro Forming Processes, Liang Luo, Zhengyi Jiang, Haina Lu, Dongbin Wei, Kezhi Linghu, Xianming Zhao, Di Wu
Optimisation Of Size-Controllable Centroidal Voronoi Tessellation For Fem Simulation Of Micro Forming Processes, Liang Luo, Zhengyi Jiang, Haina Lu, Dongbin Wei, Kezhi Linghu, Xianming Zhao, Di Wu
Faculty of Engineering and Information Sciences - Papers: Part A
Voronoi tessellation has been employed to characterise material features in Finite Element Method (FEM) simulation, however, a poor mesh quality of the voronoi tessellations causes problems in explicit dynamic simulation of forming processes. Although centroidal voronoi tessellation can partly improve the mesh quality by homogenisation of voronoi tessellations, small features, such as short edges and small facets, lead to an inferior mesh quality. Further, centroidal voronoi tessellation cannot represent all real micro structures of materials because of the almost equal tessellation shape and size. In this paper, a density function is applied to control the size and distribution of voronoi …
Molecular Dynamics Simulation On Σ5 Grain Boundaries Of Copper Bicrystal Under Tensile And Shear Deformation, Liang Zhang, Cheng Lu, A Kiet Tieu
Molecular Dynamics Simulation On Σ5 Grain Boundaries Of Copper Bicrystal Under Tensile And Shear Deformation, Liang Zhang, Cheng Lu, A Kiet Tieu
Faculty of Engineering and Information Sciences - Papers: Part A
Molecular Dynamics simulation are employed to investigate the structures and mechanical behavior of both symmetric and asymmetric Σ5[0 0 1] tilt grain boundaries (GBs) of copper bicrystal under uniaxial tension and shear deformation. Simulation results indicate that the Σ5 asymmetric GBs can facet into their corresponding symmetric GB structures. The maximum tensile stress of symmetric GBs is higher than the asymmetric ones at both 10 K and 300 K, which suggests the symmetric GBs may have a more stable boundary structures. All the Σ5 GBs investigate in this study can migrate under the shear deformation with different velocity. The migration …
Transmob: An Agent Based Simulation Of Transport Demand And Residential Mobility In South East Sydney, Pascal Perez, Nam N. Huynh, Vu Lam Cao, Rohan Wickramasuriya, Matthew J. Berryman
Transmob: An Agent Based Simulation Of Transport Demand And Residential Mobility In South East Sydney, Pascal Perez, Nam N. Huynh, Vu Lam Cao, Rohan Wickramasuriya, Matthew J. Berryman
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents an agent-based simulation, called TransMob, of transport demand and residential mobility in South East Sydney, Australia. In this model, each agent represents an individual resident of the study area. Each agent is given an initial travel diary. Agents are grouped in various types of household which generate social interdependencies and additional constrains on travel diaries. This initial synthetic population is then allowed to evolve for 20 years, driven by natural growth parameters, social bonding and migration rates. A micro-simulation component calculates daily traffic conditions and individual travel times, allowing for multi-modal journeys. The transport mode choice component …
An Agent Based Model For The Simulation Of Road Traffic And Transport Demand In A Sydney Metropolitan Area, Nam N. Huynh, Vu Cao, Rohan Wickramasuriya Denagamage, Matthew Berryman, Pascal Perez, Johan Barthelemy
An Agent Based Model For The Simulation Of Road Traffic And Transport Demand In A Sydney Metropolitan Area, Nam N. Huynh, Vu Cao, Rohan Wickramasuriya Denagamage, Matthew Berryman, Pascal Perez, Johan Barthelemy
Faculty of Engineering and Information Sciences - Papers: Part A
No abstract provided.
A Study Of Plastic Deformation Behavior During High Pressure Torsion Process By Crystal Plasticity Finite Element Simulation, Peitang Wei, Cheng Lu, A K. Tieu, Guanyu Deng
A Study Of Plastic Deformation Behavior During High Pressure Torsion Process By Crystal Plasticity Finite Element Simulation, Peitang Wei, Cheng Lu, A K. Tieu, Guanyu Deng
Faculty of Engineering and Information Sciences - Papers: Part A
High pressure torsion (HPT) is an efficient technique of producing ultrafine grained materials with exceptional small grain size. In this study, a crystal plasticity finite element method (CPFEM) model has been developed to investigate the plastic deformation behavior of pure aluminum single crystal during the HPT process. The simulation results show that, the distribution and evolution of the macroscopic plastic strain and the accumulative shear strain are similar. The value increases with the increase of the distance from the center as well as the number of revolution. The simulation is capable of reflecting the anisotropic characteristics of HPT deformation, a …
Concept And Simulation Study Of A Novel Localization Method For Robotic Endoscopic Capsules Using Multiple Positron Emission Markers, Trung Duc Than, Gursel Alici, Steven Harvey, Hao Zhou, Weihua Li
Concept And Simulation Study Of A Novel Localization Method For Robotic Endoscopic Capsules Using Multiple Positron Emission Markers, Trung Duc Than, Gursel Alici, Steven Harvey, Hao Zhou, Weihua Li
Faculty of Engineering and Information Sciences - Papers: Part A
Purpose: Over the last decade, wireless capsule endoscope has been the tool of choice for noninvasive inspection of the gastrointestinal tract, especially in the small intestine. However, the latest clinical products have not been equipped with a sufficiently accurate localization system which makes it difficult to determine the location of intestinal abnormalities, and to apply follow-up interventions such as biopsy or drug delivery. In this paper, the authors present a novel localization method based on tracking three positron emission markers embedded inside an endoscopic capsule. Methods: Three spherical 22Na markers with diameters of less than 1 mm are embedded in …
Atomistic Simulation Of Tensile Deformation Behavior Of Σ5 Tilt Grain Boundaries In Copper Bicrystal, Liang Zhang, Cheng Lu, A Kiet Tieu
Atomistic Simulation Of Tensile Deformation Behavior Of Σ5 Tilt Grain Boundaries In Copper Bicrystal, Liang Zhang, Cheng Lu, A Kiet Tieu
Faculty of Engineering and Information Sciences - Papers: Part A
Experiments on polycrystalline metallic samples have indicated that Grain boundary (GB) structure can affect many material properties related to fracture and plasticity. In this study, atomistic simulations are employed to investigate the structures and mechanical behavior of both symmetric and asymmetric ∑5[0 0 1] tilt GBs of copper bicrystal. First, the equilibrium GB structures are generated by molecular statics simulation at 0K. The results show that the ∑5 asymmetric GBs with different inclination angles (φ) are composed of only two structural units corresponding to the two ∑5 symmetric GBs. Molecular dynamics simulations are then conducted to investigate the mechanical response …
Dem Simulation Of The Behaviour Of Geogrid Stabilised Ballast Fouled With Coal, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn
Dem Simulation Of The Behaviour Of Geogrid Stabilised Ballast Fouled With Coal, Ngoc Trung Ngo, Buddhima Indraratna, Cholachat Rujikiatkamjorn
Faculty of Engineering and Information Sciences - Papers: Part A
Geogrids are commonly used in railway construction for reinforcement and stabilisation. When railway ballast becomes fouled due to ballast breakage, infiltration of coal fines, dust and subgrade soil pumping, the reinforcement effect of geogrids decreases significantly. This paper presents results obtained from Discrete Element Method (DEM) to study the interface behaviour of coal-fouled ballast reinforced by geogrid subjected to direct shear testing. In this study, irregularly-shaped aggregates (ballast) were modelled by clumping together 10-20 spheres in appropriate sizes and positions. The geogrid was modelled by bonding a large number of small spheres together to form the desired grid geometry and …
Cellular Automaton Simulation Of Hot Deformation Of Trip Steel, Ying Zhi, Xianghua Liu, Hailiang Yu
Cellular Automaton Simulation Of Hot Deformation Of Trip Steel, Ying Zhi, Xianghua Liu, Hailiang Yu
Faculty of Engineering and Information Sciences - Papers: Part A
The recrystallization process of hot deformed austenite of TRIP steel was predicted using Cellular Automaton (CA) combined with the principles of physical metallurgy. A model was developed for prediction of the dynamic and static recrystallization microstructure evolution and properties of hot deformed austenite for TRIP steel. The theoretical modeling of recrystallization was based on dislocation density. The microstructure evolution of austenite recrystallization of TRIP steel (such as the grain shape and size, volume fraction, kinetics curve of recrystallization) was predicted both visually and quantitatively. The distribution and variation of the dislocation density and flow stress were also obtained, and the …
Behavior Of Fresh And Fouled Railway Ballast Subjected To Direct Shear Testing: Discrete Element Simulation, B Indraratna, N T Ngo, C Rujikiatkamjorn, J S. Vinod
Behavior Of Fresh And Fouled Railway Ballast Subjected To Direct Shear Testing: Discrete Element Simulation, B Indraratna, N T Ngo, C Rujikiatkamjorn, J S. Vinod
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents the three-dimensional discrete element method (DEM) that was used to study the shear behaviour of fresh and coal fouled ballast in direct shear testing. The volumetric changes and stress-strain behaviour of fresh and fouled ballast were simulated and compared with the experimental results. 'Clump logic' in Particle Flow Code (PFC3D) incorporated in a MATLAB Code was used to simulate irregular shaped particles in which groups of ten to twenty spherical balls were clumped together in appropriate sizes to simulate ballast particles. Fouled ballast with various Void Contaminant Index (VCI), ranging from 20%VCI to 70%VCI, were modelled by …
Benchmarking And Validation Of A Geant4-Shadow Monte Carlo Simulation For Dose Calculations In Microbeam Radiation Therapy, Iwan Cornelius, Susanna Guatelli, Pauline Fournier, Jeffrey C. Crosbie, Manuel Sanchez Del Rio, Elke Brauer-Krisch, Anatoly Rosenfeld, Michael Lf Lerch
Benchmarking And Validation Of A Geant4-Shadow Monte Carlo Simulation For Dose Calculations In Microbeam Radiation Therapy, Iwan Cornelius, Susanna Guatelli, Pauline Fournier, Jeffrey C. Crosbie, Manuel Sanchez Del Rio, Elke Brauer-Krisch, Anatoly Rosenfeld, Michael Lf Lerch
Faculty of Engineering and Information Sciences - Papers: Part A
Microbeam radiation therapy (MRT) is a synchrotron-based radiotherapy modality that uses high-intensity beams of spatially fractionated radiation to treat tumours. The rapid evolution of MRT towards clinical trials demands accurate treatment planning systems (TPS), as well as independent tools for the verification of TPS calculated dose distributions in order to ensure patient safety and treatment efficacy. Monte Carlo computer simulation represents the most accurate method of dose calculation in patient geometries and is best suited for the purpose of TPS verification. A Monte Carlo model of the ID17 biomedical beamline at the European Synchrotron Radiation Facility has been developed, including …
Development Of Databases For Facilitating Green Roof Energy Simulation Assessments, Aloysius Decruz, Georgios Kokogiannakis, Jo Darkwa, Kate Yuan, Paul Strachan
Development Of Databases For Facilitating Green Roof Energy Simulation Assessments, Aloysius Decruz, Georgios Kokogiannakis, Jo Darkwa, Kate Yuan, Paul Strachan
Faculty of Engineering and Information Sciences - Papers: Part A
Assessments of the energy performance of green roofs have traditionally been performed with experimental and modelling procedures. Experimental green roof energy studies have significant disadvantages (expensive, time-consuming, cannot be generalised, etc.). On the other hand, modelling studies are often done with over-simplified models (for example, by ignoring the effect of moisture flows in the green roof layers) or with detailed models that require inputs which are often difficult to be obtained in practice and may involve a certain degree of uncertainty. This paper describes the methodologies for the development of databases that include data inputs that could be used within …
Monte Carlo Simulation Of The Transit Dosimetric Response Of An A-Si Electronic Portal Imaging Device, Samuel J. Blake, Aimee Mcnamara, Philip Vial, Lois Holloway, Peter Greer, Zdenka Kuncic
Monte Carlo Simulation Of The Transit Dosimetric Response Of An A-Si Electronic Portal Imaging Device, Samuel J. Blake, Aimee Mcnamara, Philip Vial, Lois Holloway, Peter Greer, Zdenka Kuncic
Faculty of Engineering and Information Sciences - Papers: Part A
Amorphous silicon (a-Si) electronic portal imaging devices (EPIDs) are x-ray detectors frequently used in radiotherapy imaging and dosimetry applicatioins. EPIDs employ a copper plate and gadolinium oxysulfide phosphor screen with an array of a-Si photodiodes to indirectly detect incident radiation. In this study, a previously developed Mote Carlo (MC) model of an a-Si EPID has been extended for transit dosimetry.