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Full-Text Articles in Engineering

Lateral Load Response Of Semi-Interlocking Mortarless Masonry-Infilled Frames, Sonam Dorji, Hossein Derakhshan, David P. Thambiratnam, Alireza Mohyeddin Mar 2024

Lateral Load Response Of Semi-Interlocking Mortarless Masonry-Infilled Frames, Sonam Dorji, Hossein Derakhshan, David P. Thambiratnam, Alireza Mohyeddin

Research outputs 2022 to 2026

Structural frames infilled with masonry material called masonry-infilled frames (MIFs) are common types of constructions around the world. These structures generally have mortared masonry as infill material which made the buildings stiff during past earthquakes and generated additional torsional forces. With a view to improve the seismic performance of MIFs this paper presents the results of a numerical simulation study on the behaviour of previously-tested MIFs with semi-interlocking masonry (SIM) material. In a simplified micro-modelling approach, the concrete and masonry materials are simulated using Concrete Damaged Plasticity technique and the joints are considered as zero-thickness cohesive interfaces modelled using traction-separation …


On Quantifying Global Carbon Emission From Oil Contaminated Lands Over Centuries, Kaveh Sookhak Lari, Greg B. Davis, Trevor Bastow, John L. Rayner Jan 2024

On Quantifying Global Carbon Emission From Oil Contaminated Lands Over Centuries, Kaveh Sookhak Lari, Greg B. Davis, Trevor Bastow, John L. Rayner

Research outputs 2022 to 2026

Petroleum releases into the subsurface contribute to global soil carbon emissions. Quantifying releases and changes in releases of carbon from soils over the lifetime of a spill is complex. Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) embodies all key mechanisms for transformation to carbon gases and their release from soils including partitioning, transport and degradation of petroleum components. Quantification of the interconnected behaviours of the soil microbiome, fluid flow, multi-component transport, partitioning, and biodegradation is crucial for understanding NSZD. Volatilization from LNAPL, aerobic biodegradation, methanogenesis, and heat production all lead to release of greenhouse gases to …


Effect Of Post-Cured Through Thickness Reinforcement On Disbonding Behavior In Skin-Stringer Configuration, Jimesh D. Bhagatji, Christopher Morris, Yogaraja Sridhar, Bodhisatwa Bhattacharjee, Krishnanand N. Kaipa, Oleksandr G. Kravchenko Jan 2024

Effect Of Post-Cured Through Thickness Reinforcement On Disbonding Behavior In Skin-Stringer Configuration, Jimesh D. Bhagatji, Christopher Morris, Yogaraja Sridhar, Bodhisatwa Bhattacharjee, Krishnanand N. Kaipa, Oleksandr G. Kravchenko

Mechanical & Aerospace Engineering Faculty Publications

An experimental investigation of interlaminar toughness for post-cured through-thickness reinforcement (PTTR) skin-stringer sub-element is presented. The improvement in the crack resistance capability of skin-stringer samples was shown through experimental testing and finite element analysis (FEA) modeling. The performance of PTTR was evaluated on a pristine and initial-disbond of the skin-stringer specimen. A macro-scale pin-spring modeling approach was employed in FEA using a non-linear spring to capture the pin failure under the mixed-mode load. The experimental results showed a 15.5% and 20.9% increase in strength for the pristine-PTTR and initial-disbond PTTR specimens, respectively. The modeling approach accurately represents the overall structural …


Crystalline–Amorphous Nanostructures: Microstructure, Property And Modelling, Binqiang Wei, Lin Li, Lin Shao, Jian Wang Apr 2023

Crystalline–Amorphous Nanostructures: Microstructure, Property And Modelling, Binqiang Wei, Lin Li, Lin Shao, Jian Wang

Department of Mechanical and Materials Engineering: Faculty Publications

Crystalline metals generally exhibit good deformability but low strength and poor irradiation tolerance. Amorphous materials in general display poor deformability but high strength and good irradiation tolerance. Interestingly, refining characteristic size can enhance the flow strength of crystalline metals and the deformability of amorphous materials. Thus, crystalline–amorphous nanostructures can exhibit an enhanced strength and an improved plastic flow stability. In addition, high-density interfaces can trap radiation-induced defects and accommodate free volume fluctuation. In this article, we review crystalline–amorphous nanocomposites with characteristic microstructures including nanolaminates, core–shell microstructures, and crystalline/amorphous-based dual-phase nanocomposites. The focus is put on synthesis of characteristic microstructures, deformation …


Modeling Wealth Distribution In A Society, Dylan Berns, Peihsien Sun, Adrian V. Gheorghe Jan 2023

Modeling Wealth Distribution In A Society, Dylan Berns, Peihsien Sun, Adrian V. Gheorghe

Engineering Management & Systems Engineering Faculty Publications

The interconnectedness of social mood, changing dynamics, income inequality, and wealth distribution underscores the complexity of understanding and addressing these issues. This complexity inspires researchers to develop models and conduct further research to gain insights into the mechanisms driving income inequality and wealth distribution. By studying these phenomena more comprehensively, one can aim to develop strategies and policies that promote a more equitable distribution of wealth and opportunities, thereby fostering social stability and economic prosperity. In the present paper, there was build a model on wealth distribution and income inequality to help people understand the complexities of wealth inequality and …


Employing Discrete Solid Phases To Represent C-S-H Solid Solutions In The Cemdata07 Thermodynamic Database To Model Cement Hydration Using The Phreeqc Geochemical Software, Niall Holmes Dr., Mark Tyrer, Denis Kelliher Oct 2022

Employing Discrete Solid Phases To Represent C-S-H Solid Solutions In The Cemdata07 Thermodynamic Database To Model Cement Hydration Using The Phreeqc Geochemical Software, Niall Holmes Dr., Mark Tyrer, Denis Kelliher

Articles

This paper presents a cement hydration model over time using the cemdata07 thermodynamic database and a series of derived discrete solid phases (DSPs) to represent calcium silicate hydrate (C-S-H) as a binary solid solution with two end-members. C-S-H in cement is amorphous and poorly crystalline with a range of molar Ca/Si ratios from 0.6 to 1.7. It displays strongly incongruent dissolution behaviour, where the release of calcium into solution is several orders of magnitude greater than silicon. It is, therefore, important that any cement hydration model provides a credible account of this behaviour. C-S-H has been described in the cemdata07 …


Modelling The Hydrating Behaviour Of Fly-Ash In Blended Cements Using Thermodynamics, Nikki Shaji, Niall Holmes Dr., Mark Tyrer Sep 2022

Modelling The Hydrating Behaviour Of Fly-Ash In Blended Cements Using Thermodynamics, Nikki Shaji, Niall Holmes Dr., Mark Tyrer

Conference papers

This paper presents a new method to thermodynamically model the hydration behaviour of fly-ash (FA) blended cements by deriving individual phase descriptions depending on the proportion of FA in the blended cement. The predicted hydrated phase assemblage, pore solution chemistries and pH over 1,000 days of hydration and with increasing FA proportions are presented. The thermodynamic data for the FA phases are derived using oxide proportions and mineral compositions are copied directly into the PHREEQC input file. The FA phases take account of all minerals to give a more accurate description of its behaviour during hydration. The calcium aluminosilicate hydrate …


Estimating Flashpoints Of Fuels And Chemical Compounds Using Hybrid Machine-Learning Techniques, Farid Amirkhani, Amir Dashti, Hossein Abedsoltan, Amir H. Mohammadi, Abdoulmohammad Gholamzadeh Chofreh, Feybi Ariani Goni, Jiří Jaromír Klemeš Sep 2022

Estimating Flashpoints Of Fuels And Chemical Compounds Using Hybrid Machine-Learning Techniques, Farid Amirkhani, Amir Dashti, Hossein Abedsoltan, Amir H. Mohammadi, Abdoulmohammad Gholamzadeh Chofreh, Feybi Ariani Goni, Jiří Jaromír Klemeš

Chemical and Biochemical Engineering Faculty Research & Creative Works

Flashpoint of organic materials is a crucial physical property in industrial applications and laboratory experiments, which provides information on safety standards and needed precautions in handling various organic materials. Proposed methods to determine the flashpoint of an organic material suffer from dependency on other physical properties of the chemical or demand complicated calculations which are time-consuming. In this work, a direct system model is proposed to anticipate the flashpoints of organic materials for a wide range of chemical compounds. The following models of genetic algorithm-adaptive neuro-fuzzy inference system, the least-squares version of the support vector machine, particle swarm optimization-adaptive neuro-fuzzy …


Recent Advances In Bone Research 2022 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet May 2022

Recent Advances In Bone Research 2022 Edition, Jean-Philippe Berteau, Laurent Pujo-Menjouet

Publications and Research

More and more scientific and engineering applications in bone research make pivotal advances in treating patients with orthopedics issues. Hence, bone research in the 21st century combines, inter alia, biology, chemistry, mathematics, and mechanics with complementary characteristics that help a holistic approach to bone-related pathologies. Nowadays, it is hard to connect new evidence when jargoning and money remain two significant obstacles to sharing knowledge. “Recent Advances In Bone Research” is a free book – no money involved at any stage - that combines the most recent efforts in bone research from several experts with different backgrounds, every expert seeks to …


Quantifying The Benefits Of In-Time And In-Place Responses To Remediate Acute Lnapl Release Incidents, Kaveh S. Lari, Andrew King, John L. Rayner, Greg B. Davis Jan 2021

Quantifying The Benefits Of In-Time And In-Place Responses To Remediate Acute Lnapl Release Incidents, Kaveh S. Lari, Andrew King, John L. Rayner, Greg B. Davis

Research outputs 2014 to 2021

Acute large volume spills from storage tanks of petroleum hydrocarbons as light non aqueous phase liquids (LNAPLs) can contaminate soil and groundwater and may have the potential to pose explosive and other risks. In consideration of an acute LNAPL release scenario, we explore the value of a rapid remediation response, and the value of installing remediation infrastructure in close proximity to the spill location, in effecting greater recovery of LNAPL mass from the subsurface. For the first time, a verified three-dimensional multi-phase numerical framework and supercomputing resources was applied to explore the significance of in-time and in-place remediation actions. A …


Advancing Ecohydrology In The 21st Century: A Convergence Of Opportunities, Andrew J. Guswa, Doerthe Tetzlaff, John S. Selker, Darryl E. Carlyle-Moses, Elizabeth W. Boyer, Michael Bruen, Carles Cayuela, Irena F. Creed, Nick Van De Giesen, Domenico Grasso, David M. Hannah, Janice E. Hudson, Sean A. Hudson, Shin'ichi Iida, Robert B. Jackson, Gabriel G. Katul, Tomo'omi Kumagai, Pilar Llorens, Flavio Lopes Ribeiro, Beate Michalzik, Kazuki Nanko, Christopher Oster, Diane E. Pataki, Catherine A. Peters, Andrea Rinaldo, Daniel Sanchez Carretero, Branimir Trifunovic, Maciej Zalewski, Marja Haagsma, Delphis F. Levia Jun 2020

Advancing Ecohydrology In The 21st Century: A Convergence Of Opportunities, Andrew J. Guswa, Doerthe Tetzlaff, John S. Selker, Darryl E. Carlyle-Moses, Elizabeth W. Boyer, Michael Bruen, Carles Cayuela, Irena F. Creed, Nick Van De Giesen, Domenico Grasso, David M. Hannah, Janice E. Hudson, Sean A. Hudson, Shin'ichi Iida, Robert B. Jackson, Gabriel G. Katul, Tomo'omi Kumagai, Pilar Llorens, Flavio Lopes Ribeiro, Beate Michalzik, Kazuki Nanko, Christopher Oster, Diane E. Pataki, Catherine A. Peters, Andrea Rinaldo, Daniel Sanchez Carretero, Branimir Trifunovic, Maciej Zalewski, Marja Haagsma, Delphis F. Levia

Engineering: Faculty Publications

Nature-based solutions for water-resource challenges require advances in the science of ecohydrology. Current understanding is limited by a shortage of observations and theories that can further our capability to synthesize complex processes across scales ranging from submillimetres to tens of kilometres. Recent developments in environmental sensing, data, and modelling have the potential to drive rapid improvements in ecohydrological understanding. After briefly reviewing advances in sensor technologies, this paper highlights how improved measurements and modelling can be applied to enhance understanding of the following ecohydrological examples: interception and canopy processes, root uptake and critical zone processes, and up-scaled effects of land …


Using Robotics And Engineering Design Inquiries To Optimize Learning For Middle Level Teachers: A Case Study, Iman Chafik Chahine, Norman Robinson Iii, Kimbeni Mansion May 2020

Using Robotics And Engineering Design Inquiries To Optimize Learning For Middle Level Teachers: A Case Study, Iman Chafik Chahine, Norman Robinson Iii, Kimbeni Mansion

Publications & Research

This exploratory case study reports findings on 20 middle-level science and mathematics teachers’ perceptions of the effectiveness of a one-year project in which teachers engaged in using robotics and engineering design inquiries in their classrooms. Principled by Bandura’s Social Learning Theory (SLT) and using mixed methods approaches, the study measured teachers' efficacy through the Mathematics Teaching Efficacy Belief Instrument (MTEBI) and observation logs before and after the program. The results of this study showed statistically significant differences between PRE MTEBI and POST MTEBI scores. Furthermore, five themes emerged that illuminated potential affordances and constraints that teachers perceive as opportunities and …


Coupled Modelling And Advanced Control For Smooth Operation Of A Grid Connected Linear Electric Generator Based Wave-To-Wire System, Safdar Rasool, Md Rabiul Islam, Kashem M. Muttaqi, Danny Sutanto Jan 2020

Coupled Modelling And Advanced Control For Smooth Operation Of A Grid Connected Linear Electric Generator Based Wave-To-Wire System, Safdar Rasool, Md Rabiul Islam, Kashem M. Muttaqi, Danny Sutanto

Faculty of Engineering and Information Sciences - Papers: Part B

The perpetual oscillations of ocean waves produce potential energy, which can be converted to electrical energy with the help of direct drive linear generators. The fluctuating generated power poses a major challenge when it is supplied to the power grid. In this paper, a supercapacitor provides the short-term energy storage to buffer and smooth out the power fluctuations. A new coupled model of a wave energy converter and a linear generator is proposed for its response characterization under varying system conditions. The developed model and an advanced control strategy is used to exhibit a smooth and stable operation of the …


Numerical Modelling Of Track Behavior Capturing Particle Breakage Under Dynamic Loading, Ngoc Trung Ngo, Buddhima Indraratna Jan 2020

Numerical Modelling Of Track Behavior Capturing Particle Breakage Under Dynamic Loading, Ngoc Trung Ngo, Buddhima Indraratna

Faculty of Engineering and Information Sciences - Papers: Part B

No abstract provided.


Activation Of Biochar From Olive Residues: A Predictive Model For Yield And Surface Area, Franco Berruti, Anastasia Colomba, Cedric Briens Sep 2019

Activation Of Biochar From Olive Residues: A Predictive Model For Yield And Surface Area, Franco Berruti, Anastasia Colomba, Cedric Briens

Bio-Char II: Production, Characterization and Applications

A great amount of work in the literature is dedicated to the kinetic modelling of gasification reactions, while a limited number of authors have paid attention to the evolution of physical parameters, which are very important in the case in which the reaction is applied to the production of activated carbons. The Volume reaction model (VRM) [1], the Shrinking core model (SCM) [2], and the Random pore model (RPM) [3] are unable to provide a relationship between kinetics and the physical properties of the activated carbon and, particularly, between yield and surface area.

Please click Additional Files below to see …


Challenges And Progresses Made On The Microkinetic Description Of Lignin Liquefaction: Application Of Group Contribution Methods, Manuel Garcia-Perez, Evan Terrell, Linda Broadbelt Jun 2019

Challenges And Progresses Made On The Microkinetic Description Of Lignin Liquefaction: Application Of Group Contribution Methods, Manuel Garcia-Perez, Evan Terrell, Linda Broadbelt

Pyroliq 2019: Pyrolysis and Liquefaction of Biomass and Wastes

In this presentation a comprehensive microkinetic modelling framework and experimental tools are used to describe product yield and composition of direct lignin liquefaction processes with and without solvents (See Figure 1). With the framework proposed we aim to develop a unified theory and models capable of describing both dry (pyrolysis) and wet (hydrothermal and solvolysis) lignin liquefaction processes. An important phenomenon that has been shown to occur during lignin pyrolysis (as well as cellulose) is the formation of a liquid intermediate phase, and subsequent ejection of heavy products (>~250 Da) as aerosols from this intermediate. In our presentation we …


Natural Source Zone Depletion Of Lnapl: A Critical Review Supporting Modelling Approaches, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner, Trevor P. Bastow, Geoffrey J. Puzon Jan 2019

Natural Source Zone Depletion Of Lnapl: A Critical Review Supporting Modelling Approaches, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner, Trevor P. Bastow, Geoffrey J. Puzon

Research outputs 2014 to 2021

Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) includes partitioning, transport and degradation of LNAPL components. NSZD is being considered as a site closure option during later stages of active remediation of LNAPL contaminated sites, and where LNAPL mass removal is limiting. To ensure NSZD meets compliance criteria and to design enhanced NSZD actions if required, residual risks posed by LNAPL and its long term behaviour require estimation. Prediction of long-term NSZD trends requires linking physicochemical partitioning and transport processes with bioprocesses at multiple scales within a modelling framework. Here we expand and build on the knowledge …


Consequence Modelling Of Co2 Pipeline Failure, Xiong Liu, Ajit R. Godbole, Cheng Lu, Guillaume Michal, Valerie M. Linton Jan 2019

Consequence Modelling Of Co2 Pipeline Failure, Xiong Liu, Ajit R. Godbole, Cheng Lu, Guillaume Michal, Valerie M. Linton

Faculty of Engineering and Information Sciences - Papers: Part B

This paper describes the experimental investigation and Computational Fluid Dynamics (CFD) simulations of the dispersion of CO2 following high-pressure dense phase CO2 pipeline failure. A full-scale burst test was carried out to simulate a CO2 pipeline failure in the real world. The atmospheric dispersion of the CO2 following the explosive release was measured. The CFD models were validated against the experimental data. The models were then used to estimate the consequence distances related to CO2 dispersion following failure of pipelines with various diameters under different wind speeds. This approach provides a predictive formula for the consequence distances of CO2 transmission …


Improved Performance Of Ballasted Tracks At Transition Zones: A Review Of Experimental And Modelling Approaches, Buddhima Indraratna, Muhammad Babar Sajjad, Ngoc Trung Ngo, A Correia, Richard B. Kelly Jan 2019

Improved Performance Of Ballasted Tracks At Transition Zones: A Review Of Experimental And Modelling Approaches, Buddhima Indraratna, Muhammad Babar Sajjad, Ngoc Trung Ngo, A Correia, Richard B. Kelly

Faculty of Engineering and Information Sciences - Papers: Part B

Track transitionssuch as bridge approaches, road crossings and shifts from slab track to ballasted track are common locations wheretrack degradation accelerates due to dynamic and high impact forces; as a consequence there is higher differential settlement. Thesetypes of discontinuities cause an abrupt change in the structural responseof the track due mainly tovariations in stiffness and track damping. Track transitionzones are prone to an accelerated deterioration of track material and geometrythat leads to increased maintenance costs.Track deteriorationalso leads to vehicle degradation due to enhanced acceleration, low frequency oscillation, and high frequency vibrations. While ballastdeterioration is amajor factor affecting thestability and longevity …


Introducing A New Cement Hydration And Microstructure Model, Niall Holmes, Anselm Griffin, Bernard Enright, Denis Keliher Aug 2018

Introducing A New Cement Hydration And Microstructure Model, Niall Holmes, Anselm Griffin, Bernard Enright, Denis Keliher

Conference papers

This paper presents a new cement hydration model to predict the microstructure evolution of hydrating tricalcium silicate (C3S). The model is written in MATLAB and employs the continuum approach and integrated particle kinetic relationships to show the change in C3S and the growth of Calcium Silicate Hydrate (C-S-H) and Calcium Hydroxide (CH) in the pore space over time.

Cement hydration is a highly complex process. While hydration models should never completely remove experimental analysis, they are an aid to better understand cement hydration and microstructure development by providing a method to analyse a large number of pastes with different cementitious …


Curation Of A Cho Dg44 Genome Scale Model And Application To Support Cell Culture Development Process, Cyrielle Calmels, Laetitia Malphettes, Mikael Rørdam Andersen May 2018

Curation Of A Cho Dg44 Genome Scale Model And Application To Support Cell Culture Development Process, Cyrielle Calmels, Laetitia Malphettes, Mikael Rørdam Andersen

Cell Culture Engineering XVI

Genome scale models (GSM) have become a useful tool to connect different omics dataset into a single computational framework, thus giving a good overview of the flux distribution and metabolites interconnections in a specific environmental condition. A community genome-scale metabolic network reconstruction of Cricetulus griseus and cell line specific models have been recently developed 1. The main objectives with the use of the published CHO DG44 model were to enhance industrial bioprocess performance by suggesting genetic or metabolic targets, as well as strategies for medium optimization, and by bringing more fundamental knowledge about CHO cell metabolism. In a first step, …


Woody And Agricultural Biomass Diversity In Torrefaction: A Complete Study In Solid Conversion And Volatiles Formation On Tga-Gcms, María González Martínez, Capucine Dupont, Xuan Mi Meyer, Christophe Gourdon Aug 2017

Woody And Agricultural Biomass Diversity In Torrefaction: A Complete Study In Solid Conversion And Volatiles Formation On Tga-Gcms, María González Martínez, Capucine Dupont, Xuan Mi Meyer, Christophe Gourdon

Biochar: Production, Characterization and Applications

Nowadays, there is an increasing awareness on the importance of biomass waste as a renewable source of energy, materials and chemicals. In this context, the European project MOBILE FLIP aims at developing and demonstrating mobile conversion processes suitable with various underexploited agro- and forest based biomass resources in order to produce energy carriers, materials and chemicals. One of these processes is torrefaction, which consists in a mild thermal treatment, occurring typically between 200 and 300°C during a few tens of minutes in a default-oxygen atmosphere.

Please click on the file below for full content of the abstract.


Embrace The Unknown: Stop Saying “It’S Too Hard” And Start Embracing Uncertainty In Your Mine Plans, C. Roos Feb 2017

Embrace The Unknown: Stop Saying “It’S Too Hard” And Start Embracing Uncertainty In Your Mine Plans, C. Roos

Mining Engineering

Nearly every input to a mine plan is based on an estimate. The estimates may be from sample data, historical information, models, or personal opinion, but in all cases, these values are simply expected values (means). In real life, we do not get to iterate the exact conditions at our mining operation many times to ensure that that average value is attained. The expected value also tells us nothing about the spread of values that that input might take on. The result is a significant amount of unquantified uncertainty in our mine plans. Unfortunately, it is often too expensive or …


Editorial: Modelling And Simulation In Health Care Systems, Nagesh Shukla, Pascal Perez, Manoj K. Tiwari, Darek Ceglarek, Joana M. Dias Jan 2017

Editorial: Modelling And Simulation In Health Care Systems, Nagesh Shukla, Pascal Perez, Manoj K. Tiwari, Darek Ceglarek, Joana M. Dias

Faculty of Engineering and Information Sciences - Papers: Part A

Increasingly, changes in population demography, technological and medical advancements, and others, have affected the paradigm of health and social care systems worldwide. These changes have direct effect on organisation and working of health care systems whether they are hospitals, general practitioners or long-term care. An efficient and effective health care system is crucial for high quality of the life in the society. In recent times, major challenges faced by health care systems are accurate diagnosis, operational issues (such as bottlenecks, low throughput, low resource utilisation), hospital redesign, workforce planning and scheduling, streamlining of patient flow, performance management, disease monitoring, and …


Application Of Fractional Calculus In Modelling Ballast Deformation Under Cyclic Loading, Yifei Sun, Buddhima Indraratna, John Philip Carter, Timothy R. Marchant, Sanjay Nimbalkar Jan 2017

Application Of Fractional Calculus In Modelling Ballast Deformation Under Cyclic Loading, Yifei Sun, Buddhima Indraratna, John Philip Carter, Timothy R. Marchant, Sanjay Nimbalkar

Faculty of Engineering and Information Sciences - Papers: Part A

Most constitutive models can only simulate cumulative deformation after a limited number of cycles. However, railroad ballast usually experiences a large number of train passages that cause history-dependent long-term deformation. Fractional calculus is an efficient tool for modelling this phenomenon and therefore is incorporated into a constitutive model for predicting the cumulative deformation. The proposed model is further validated by comparing the model predictions with a series of corresponding experimental results. It is observed that the proposed model can realistically simulate the cumulative deformation of ballast from the onset of loading up to a large number of load cycles.


Modelling And Control Of A Novel Walker Robot For Post-Stroke Gait Rehabilitation, Emre Sariyildiz, Hsiao-Ju Cheng, Gokhan M. Yagli, Haoyong Yu Jan 2017

Modelling And Control Of A Novel Walker Robot For Post-Stroke Gait Rehabilitation, Emre Sariyildiz, Hsiao-Ju Cheng, Gokhan M. Yagli, Haoyong Yu

Faculty of Engineering and Information Sciences - Papers: Part B

In this paper, a novel walker robot is proposed for post-stroke gait rehabilitation. It consists of an omni-directional mobile platform which provides high mobility in horizontal motion, a linear motor that moves in vertical direction to support the body weight of a patient and a 6-axis force/torque sensor to measure interaction force/torque between the robot and patient. The proposed novel walker robot improves the mobility of pelvis so it can provide more natural gait patterns in rehabilitation. This paper analytically derives the kinematic and dynamic models of the novel walker robot. Simulation results are given to validate the proposed kinematic …


Gas Reservoir And Emission Modelling To Evaluate Gas Drainage To Control Tailgate Gas Concentrations And Fugitive Emissions, Dennis J. Black Jan 2017

Gas Reservoir And Emission Modelling To Evaluate Gas Drainage To Control Tailgate Gas Concentrations And Fugitive Emissions, Dennis J. Black

Faculty of Engineering and Information Sciences - Papers: Part B

The process of longwall coal extraction coal causes fractures in the overlying and underlying strata and these fractures become pathways for gas released from adjacent coal seams to flow into the mine workings and contaminate the ventilation air. If the rate of gas emission exceeds the diluting capacity of the ventilation air, the gas concentration will increase and exceed the statutory limit resulting in production delays.All potential gas sources within the planned mining area, including coal seams located above and below the working seam, should be identified and sufficient gas data collected and used to determine the specific gas emission …


Flash Sintering Of Srtio3, Fabian Lemke Mar 2016

Flash Sintering Of Srtio3, Fabian Lemke

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Since the first reports of flash sintering in 2010 the community is continuously growing. Several parameters have been identified to be important gaining access to flash sintering, e.g. the temperature change due to joule heating, changes in the microstructure, polarization of defects or other effects on the defect chemistry. Analyzing the process is raised to another level of complexity compared to conventional sintering.

Sintering and grain growth experiments under an electrical field are conducted with SrTiO3. The results are compared to our existing database, implying simulations of the defect-chemistry, to discriminate the most important parameters in the flash sintering process. …


Modelling Water Molecules Inside Cyclic Peptide Nanotubes, Prangsai Tiangtrong, Ngamta Thamwattana, Duangkamon Baowan Jan 2016

Modelling Water Molecules Inside Cyclic Peptide Nanotubes, Prangsai Tiangtrong, Ngamta Thamwattana, Duangkamon Baowan

Faculty of Engineering and Information Sciences - Papers: Part A

Cyclic peptide nanotubes occur during the selfassembly process of cyclic peptides. Due to the ease of synthesis and ability to control the properties of outer surface and inner diameter by manipulating the functional side chains and the number of amino acids, cyclic peptide nanotubes have attracted much interest from many research areas. A potential application of peptide nanotubes is their use as artificial transmembrane channels for transporting ions, biomolecules and waters into cells. Here, we use the Lennard-Jones potential and a continuum approach to study the interaction of a water molecule in a cyclo[(-DAla- L-Ala)4-] peptide nanotube. Assuming that each …


Transient Cfd Modelling Of Low-Temperature Spontaneous Heating Behaviour In Multiple Coal Stockpiles With Wind Forced Convection, Jian Zhang, Yuntao Liang, Ting X. Ren, Zhongwei Wang, Gongda Wang Jan 2016

Transient Cfd Modelling Of Low-Temperature Spontaneous Heating Behaviour In Multiple Coal Stockpiles With Wind Forced Convection, Jian Zhang, Yuntao Liang, Ting X. Ren, Zhongwei Wang, Gongda Wang

Faculty of Engineering and Information Sciences - Papers: Part A

Spontaneous heating of coal stockpile has long been a thermal dynamic hazard during coal storage, processing, and transport. A transient non-equilibrium thermal CFD model has been developed to study the low-temperature self-heating behaviour of coal in multiple stockpiles under different prevailing wind conditions. Modelling results from the initial steady wind flow simulation indicate that a wake region can be induced on the leeward side of each coal stockpile. Pressure coefficient drops when the wind stream encounters or leaves a stockpile and the pressure coefficient profiles of multiple stockpiles tend to have more resemblance with a wider spacing. The first stockpile …