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2021

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A Review Of Bast Fibres And Their Composites: Part 4 ~ Organisms And Enzyme Processes, John Summerscales Jan 2021

A Review Of Bast Fibres And Their Composites: Part 4 ~ Organisms And Enzyme Processes, John Summerscales

School of Engineering, Computing and Mathematics

No abstract provided.


Fatigue Crack Growth Of Natural Rubber/Butadiene Rubber Blend Containing Waste Tyre Rubber Powders, Ismawi Hassim Dh Abang, F Abraham, J Summerscales, P Brown Jan 2021

Fatigue Crack Growth Of Natural Rubber/Butadiene Rubber Blend Containing Waste Tyre Rubber Powders, Ismawi Hassim Dh Abang, F Abraham, J Summerscales, P Brown

School of Engineering, Computing and Mathematics

Fatigue crack growth in NR/BR compound and the effect of two different types of recycled rubber powder (RRP) i.e. micronized cryo-ground 74 μm and ambient-ground 400 μm were studied using fracture mechanics approach. Absolute and relative hysteresis losses using single-edge notch tensile (SENT) specimens were determined with a displacement-controlled strain compensating for permanent set of the samples throughout the Fatigue Crack Growth (FCG) experiments. Results indicated a correlation between absolute/relative hysteresis loss and fatigue crack growth rate under specific dynamic strain amplitudes. Differences in relative hysteresis loss showed that additional energy dissipation, due to multiple new crack surfaces at the …


N-Photon Amplitudes In A Plane-Wave Background, James P. Edwards, Christian Schubert Jan 2021

N-Photon Amplitudes In A Plane-Wave Background, James P. Edwards, Christian Schubert

School of Engineering, Computing and Mathematics

We use the worldline formalism to derive master formulas for the one-loop N-photon amplitudes in a plane-wave background, for both scalar and spinor quantum electrodynamics. This generalises previous work by Ilderton and Torgrimsson for the vacuum polarisation case, although with some change in methodology since, instead of evaluating the path integral on the semi-classical trajectory, we use the special kinematics of the plane-wave background to uncover the crypto-gaussian character of this type of worldline path integral.


Application Of Big-Data For Epidemiological Studies Of Refractive Error, James Loughman Jan 2021

Application Of Big-Data For Epidemiological Studies Of Refractive Error, James Loughman

Articles

To examine whether data sourced from electronic medical records (EMR) and a large industrial spectacle lens manufacturing database can estimate refractive error distribution within large populations as an alternative to typical population surveys of refractive error.


A Numerical Investigation Of The Sealing Performance And The Strength Of A Raised Face Metallic Bolted Flange Joint, Muhsin Aljuboury, Md Jahir Rizvi, Stephen Grove, Richard Cullen Jan 2021

A Numerical Investigation Of The Sealing Performance And The Strength Of A Raised Face Metallic Bolted Flange Joint, Muhsin Aljuboury, Md Jahir Rizvi, Stephen Grove, Richard Cullen

School of Engineering, Computing and Mathematics

No abstract provided.


New Algorithm For Optimised Fitting Of Dic Data To Crack Tip Plastic Zone Using The Cjp Model, B Yang, Z Wei, Fa Díaz, Z Liao, Mn James Jan 2021

New Algorithm For Optimised Fitting Of Dic Data To Crack Tip Plastic Zone Using The Cjp Model, B Yang, Z Wei, Fa Díaz, Z Liao, Mn James

School of Engineering, Computing and Mathematics

The work presented in this paper provides guidance in optimally determining the appropriate fitting region used in digital image correlation (DIC) when fitting a crack tip field model to DIC data. In this work, the technique is applied to the CJP crack tip field model and uses the Levenberg-Marguardt (L-M) iterative method to solve for the crack tip position. This is combined with an error analysis of the main term of the Williams series expansion for crack tip stresses and the extrapolation of Saint-Venant’s principle to determine the optimum fitting region for use in DIC fit with the multi-parameter solution …


Limitations Of Small-Scale Yielding For Fatigue Crack Growth, B Marques, Mf Borges, Fv Antunes, Jm Vasco-Olmo, Fa Díaz, Mn James Jan 2021

Limitations Of Small-Scale Yielding For Fatigue Crack Growth, B Marques, Mf Borges, Fv Antunes, Jm Vasco-Olmo, Fa Díaz, Mn James

School of Engineering, Computing and Mathematics

The work described here has led to a simple criterion that defines the boundary of the small-scale yielding, SSY, regime to avoid invalid use of the LEFM parameter, ΔK, as the characterising parameter for fatigue crack growth rate. The approach proposed is based on the analysis of crack tip opening displacement, CTOD, and its separation into elastic and plastic components. SSY conditions are shown to dominate when the elastic component of CTOD is >75% of the total CTOD measured at a distance of 8 μm (the finite element mesh size) behind the crack tip, i.e., Δδe/Δδt > 75%. Large-scale yielding, LSY, …


Cross-Sectional Flattening-Induced Nonlinear Damped Vibration Of Elastic Tubes Subjected To Transverse Loads, Jue Zhu, Wei Bin Yuan, Long Yuan Li Jan 2021

Cross-Sectional Flattening-Induced Nonlinear Damped Vibration Of Elastic Tubes Subjected To Transverse Loads, Jue Zhu, Wei Bin Yuan, Long Yuan Li

School of Engineering, Computing and Mathematics

No abstract provided.


Comparative Mechanical And Microstructural Properties Of High Calcium Fly Ash One-Part Geopolymers Activated With Na2sio3-Anhydrous And Naalo2, Ooi Wan-En, Liew Yun-Ming, Heah Cheng-Yong, Mohd Mustafa Al Bakri Abdullah, Long Yuan Li, Li Ngee Ho, Foo Kai Loong, Ong Shee-Ween, Ng Hui-Teng, Ng Yong-Sing, Nur Ain Jaya Jan 2021

Comparative Mechanical And Microstructural Properties Of High Calcium Fly Ash One-Part Geopolymers Activated With Na2sio3-Anhydrous And Naalo2, Ooi Wan-En, Liew Yun-Ming, Heah Cheng-Yong, Mohd Mustafa Al Bakri Abdullah, Long Yuan Li, Li Ngee Ho, Foo Kai Loong, Ong Shee-Ween, Ng Hui-Teng, Ng Yong-Sing, Nur Ain Jaya

School of Engineering, Computing and Mathematics

This paper investigates the effect of varying solid alkali activators on the fresh and hardened properties and microstructural changes of one-part geopolymers (OPGs). Single and binary solid alkali activators were used to activate high calcium fly ash. The alkali activators were either solely sodium metasilicate (Na2SiO3) or a combination of sodium aluminate (NaAlO2) and sodium metasilicate (Na2SiO3). The OPG activated with anhydrous Na2SiO3 achieved an excellent 28-day compressive strength of 83.6 MPa while OPG activated with NaAlO2 and Na2SiO3 attained a compressive strength of 45.1 MPa. The Na2SiO3-activated OPG demonstrated better fluidity than the OPG activated with NaAlO2 and Na2SiO3 …


The Use Of Cyber Ranges In The Maritime Context: Assessing Maritime-Cyber Risks, Raising Awareness, And Providing Training, Kimberly Tam, Kemedi Moara-Nkwe, Kevin D. Jones Jan 2021

The Use Of Cyber Ranges In The Maritime Context: Assessing Maritime-Cyber Risks, Raising Awareness, And Providing Training, Kimberly Tam, Kemedi Moara-Nkwe, Kevin D. Jones

School of Engineering, Computing and Mathematics

A good defensive strategy against evolving cyber threats and cybercrimes is to raise awareness and use that awareness to prepare technical mitigation and human defense strategies. A prime way to do this is through training. While there are already many sectors employing this strategy (e.g., space, smart buildings, business IT), the maritime sector has yet to take advantage of the available cyber-range technology to assess cyber risks and create appropriate training to meet those risks. Cyber security training can come in 2 forms; the first is so security professionals can raise their awareness on the latest and most urgent issues …


Julian Stander, Katerina Tzioli And Mario Cortina Borja: 200 Years Of Greek Independence… And Pms, J Stander, K Tzioli, Borja M Cortina Jan 2021

Julian Stander, Katerina Tzioli And Mario Cortina Borja: 200 Years Of Greek Independence… And Pms, J Stander, K Tzioli, Borja M Cortina

School of Engineering, Computing and Mathematics

No abstract provided.


Walking Through Virtual Doors: A Study On The Effects Of Virtual Location Changes On Memory, Paul W.L. Watson, Swen Gaudl Jan 2021

Walking Through Virtual Doors: A Study On The Effects Of Virtual Location Changes On Memory, Paul W.L. Watson, Swen Gaudl

School of Engineering, Computing and Mathematics

The spaces we inhabit can shape and influence the way in which we learn or reinforce information. Virtual reality (VR) is a technology that allows us to alter and create designed environments with great freedom over the visual, audio, and narrative elements. This freedom would benefit from further guidelines that detail approaches and implementations to best achieve desired information delivery goals. In this paper we present findings of a study that applies location-based memory strategies to VR environments, with the aim to aid word list recall without the subjects being required to apply any memory strategy themselves. Our findings suggest …


Early Detection Of Alzheimer's Disease With Blood Plasma Proteins Using Support Vector Machines, Chima S. Eke, Emmanuel Jammeh, Xinzhong Li, Camille Carroll, Stephen Pearson, Emmanuel Ifeachor Jan 2021

Early Detection Of Alzheimer's Disease With Blood Plasma Proteins Using Support Vector Machines, Chima S. Eke, Emmanuel Jammeh, Xinzhong Li, Camille Carroll, Stephen Pearson, Emmanuel Ifeachor

Peninsula Medical School

No abstract provided.


A Sph Model With Open Relaxation Boundary For Wave Generation And Absorption, G Zhu, J Hughes, S Zheng, D Greaves Jan 2021

A Sph Model With Open Relaxation Boundary For Wave Generation And Absorption, G Zhu, J Hughes, S Zheng, D Greaves

School of Engineering, Computing and Mathematics

In this paper, a numerical wave tank with open relaxation boundaryfor wave simulation is presented under the framework of weakly compressible Smoothed Particle Hydrodynamics (SPH). The open relaxationboundary consists of open boundaries and relaxation particles. A relaxation function is applied for the relaxation particles which are placed between the inflow/outflow zone and the fluid domain. Open particles lie inthe inflow/outflow regions to avoid kernel truncation. The open particlesand relaxation particles can be created and deleted depending on the fluidmotion around the open boundaries, and the properties of these particlescan be obtained from theoretical resolution or by extrapolating withinthe domain. The …


Path Determination For Network Slicing In Wireless Mesh Disaster Networks, A Seng, U Trick, A Lehmann, B Ghita Jan 2021

Path Determination For Network Slicing In Wireless Mesh Disaster Networks, A Seng, U Trick, A Lehmann, B Ghita

School of Engineering, Computing and Mathematics

No abstract provided.


Role Of Atmospheric Indices In Describing Inshore Directional Wave Climate In The United Kingdom And Ireland, T. Scott, R. J. Mccarroll, G. Masselink, B. Castelle, G. Dodet, A. Saulter, A. A. Scaife, N. Dunstone Jan 2021

Role Of Atmospheric Indices In Describing Inshore Directional Wave Climate In The United Kingdom And Ireland, T. Scott, R. J. Mccarroll, G. Masselink, B. Castelle, G. Dodet, A. Saulter, A. A. Scaife, N. Dunstone

School of Biological and Marine Sciences

Improved understanding of how our coasts will evolve over a range of time scales (years-decades) is critical for effective and sustainable management of coastal infrastructure. A robust knowledge of the spatial, directional and temporal variability of the inshore wave climate is required to predict future coastal evolution and hence vulnerability. However, the variability of the inshore directional wave climate has received little attention, and an improved understanding could drive development of skillful seasonal or decadal forecasts of coastal response. We examine inshore wave climate at 63 locations throughout the United Kingdom and Ireland (1980–2017) and show that 73% are directionally …


Extreme Responses Of A Hinged Raft Type Wave Energy Convertor, T Tosdevin, S Jin, A Caio, D Simmonds, M Hann, D Greaves Jan 2021

Extreme Responses Of A Hinged Raft Type Wave Energy Convertor, T Tosdevin, S Jin, A Caio, D Simmonds, M Hann, D Greaves

School of Engineering, Computing and Mathematics

Much attention has been paid in recent years to the determination of design loads for moored floating structures and the application of established methodologies for fixed structures have been found to be ineffective. This paper experimentally investigates extreme responses of a lazy S moored 1:20 scale model of Mocean Energy’s Blue Star wave energy convertor (WEC) along the 1 year return contour. The device is a hinged raft type WEC and the extreme responses studied include mooring loads and snatch load events. Long irregular wave time series are used in the estimation of extreme value distributions of the mooring load …


A Linear Predictive Coding Filtering Method For Time-Resolved Morphology Of Eeg Activity, Jin Xu, Mark Davis, Ruairí De Fréin Jan 2021

A Linear Predictive Coding Filtering Method For Time-Resolved Morphology Of Eeg Activity, Jin Xu, Mark Davis, Ruairí De Fréin

Conference papers

This paper introduces a new time-resolved spectral analysis method based on the Linear Prediction Coding (LPC) method that is particularly suited to the study of the dynamics of EEG (Electroencephalography) activity. The spectral dynamics of EEG signals can be challenging to analyse as they contain multiple frequency components and are often corrupted by noise. The LPC Filtering (LPCF) method described here processes the LPC poles to generate a series of reduced-order filter transform functions which can accurately estimate the dominant frequencies. The LPCF method is a parameterized time-frequency method that is suitable for identifying the dominant frequencies of multiple-component signals …


Direct Multiplexing Of Low Order Aberration Modes In A Photopolymerbased Holographic Element For Analog Holographic Wavefront Sensing, Emma Branigan, Suzanne Martin, Matthew Sheehan, Kevin Murphy Jan 2021

Direct Multiplexing Of Low Order Aberration Modes In A Photopolymerbased Holographic Element For Analog Holographic Wavefront Sensing, Emma Branigan, Suzanne Martin, Matthew Sheehan, Kevin Murphy

Conference Papers

The fabrication of an analog holographic wavefront sensor, capable of detecting the low order defocus aberration, was achieved in an acrylamide-based photopolymer. While other implementations of holographic wavefront sensors have been carried out digitally, this process utilises a recording setup consisting only of conventional refractive elements so the cost and complexity of holographic optical element (HOE) production could be much reduced. A pair of diffraction spots, corresponding to a maximum and minimum amount of defocus, were spatially separated in the detector plane by multiplexing two HOEs with different carrier spatial frequencies. For each wavefront with a known aberration that was …


Winter Measurements Of Heavy-Duty Vehicles To Characterize The Cold Temperature Effectiveness Of Selective Catalytic Reductions Catalyst In Controlling Oxide Of Nitrogen Emissions, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald Jan 2021

Winter Measurements Of Heavy-Duty Vehicles To Characterize The Cold Temperature Effectiveness Of Selective Catalytic Reductions Catalyst In Controlling Oxide Of Nitrogen Emissions, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald

Fuel Efficiency Automobile Test Publications

No abstract provided.


On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2020, Gary A. Bishop Jan 2021

On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2020, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.


A Novel User Oriented Network Forensic Analysis Tool, Dany Joy Jan 2021

A Novel User Oriented Network Forensic Analysis Tool, Dany Joy

School of Engineering, Computing and Mathematics Theses

In the event of a cybercrime, it is necessary to examine the suspect’s digital device(s) in a forensic fashion so that the culprit can be presented in court along with the extracted evidence(s). But, factors such as existence and availability of anti-forensic tools/techniques and increasing replacement of hard disk drives with solid state disks have the ability to eradicate critical evidences and/or ruin their integrity. Therefore, having an alternative source of evidence with a lesser chance of being tampered with can be beneficial for the investigation. The organisational network traffic can fit into this role as it is an independent …


Assessing Focused Wave Impacts On Floating Wave Energy Converters Using Openfoam, Scott Andrew Brown, Edward Jack Ransley, Deborah M. Greaves Jan 2021

Assessing Focused Wave Impacts On Floating Wave Energy Converters Using Openfoam, Scott Andrew Brown, Edward Jack Ransley, Deborah M. Greaves

School of Engineering, Computing and Mathematics

This study considers focused wave interactions with floating wave energy converters and represents an individual contribution to the CCP-WSI blind test series 2, in which the submitted results are compared against both physical and alternative numerical solutions for varying wave steepness achieved through changes in peak frequency. Reducing the time taken to provide reliable results is critical if computational fluid dynamics (CFD) is to become a routine design tool for offshore renewable energy devices. This can potentially be achieved by simplifying simulation set-up, and hence reduce the required man-hours, through standardised ‘best practice’ procedures. In order to achieve this, it …


A Novel Method Based On Long Short Term Memory Network And Discrete-Time Zeroing Neural Algorithm For Upper-Limb Continuous Estimation Using Semg Signals, Yuanyuan Chai, Keping Liu, Chunxu Li, Zhongbo Sun, Long Jin, Tian Shi Jan 2021

A Novel Method Based On Long Short Term Memory Network And Discrete-Time Zeroing Neural Algorithm For Upper-Limb Continuous Estimation Using Semg Signals, Yuanyuan Chai, Keping Liu, Chunxu Li, Zhongbo Sun, Long Jin, Tian Shi

School of Engineering, Computing and Mathematics

In this paper, a novel closed-loop model based on surface electromyography (sEMG) comprised a long short term memory (LSTM) network and discrete-time zeroing neural algorithm called zeroing neural network (ZNN), which is developed to estimate joint angles and angular velocities of human upper limb with joint damping. The dynamic model of human upper limb with joint damping is set up as the initial equation. Then, the LSTM network is proposed as an open-loop model which described the input-output relationship between the sEMG signals and joint motion intention. Besides, a novel closed-loop model is built via ZNN for eliminating the predicted …


Analytic Integrability Of Certain Resonant Saddle, Colin Christopher, Jaume Giné Jan 2021

Analytic Integrability Of Certain Resonant Saddle, Colin Christopher, Jaume Giné

School of Engineering, Computing and Mathematics

No abstract provided.


On The Relation Between Robustness, Evolvability And Phenotypic Complexity: Insight From Artificial Evolutionary Experiments, Nicola Milano Jan 2021

On The Relation Between Robustness, Evolvability And Phenotypic Complexity: Insight From Artificial Evolutionary Experiments, Nicola Milano

School of Engineering, Computing and Mathematics Theses

This thesis addresses the study of evolutionary methods to achieve robustness and evolvability in artificial systems. Chapter 1 introduces the research area, reviews the state of the art, discusses promising research directions, and presents the two major scientific objectives of the thesis. The first objective, which is covered in Chapter 2, is to verify and exploit the impact of the environmental variations on the evolvability of an artificial system. This is accomplished through the use of two experimental setup: the simulation of digital circuits and the simulation of a robotic agent situated in an external environment. Digital circuits are used …


Solid Waste Management In Developing Countries: Reusing Of Steel Slag Aggregate In Eco-Friendly Interlocking Concrete Paving Blocks Production, Oluwarotimi Olofinnade, Ayoyinka Morawo, Oluwatomisin Okedairo, Boksun Kim Jan 2021

Solid Waste Management In Developing Countries: Reusing Of Steel Slag Aggregate In Eco-Friendly Interlocking Concrete Paving Blocks Production, Oluwarotimi Olofinnade, Ayoyinka Morawo, Oluwatomisin Okedairo, Boksun Kim

School of Engineering, Computing and Mathematics

The needs to meet the global demand for the conservation of non-renewable resources has necessitated the efforts of finding alternative materials. This current study investigates the beneficial utilization of the crushed waste furnace steel slag as a replacement for natural sand in concrete interlocking paving block units’ production for pedestrian and non-traffic applications. A total number of 144 paver samples were cast at replacement percentages of 0, 20, 40, 60, 80 and 100 % by weight of sand using a mix proportion ratio of 1:1.5:3 (cement: sand: granite) at a constant water-cement ratio of 0.5, targeting a strength of 20 …


Improved Htm Spatial Pooler With Homeostatic Plasticity Control, Damir Dobric, Andreas Pech, Bogdan Ghita, Thomas Wennekers Jan 2021

Improved Htm Spatial Pooler With Homeostatic Plasticity Control, Damir Dobric, Andreas Pech, Bogdan Ghita, Thomas Wennekers

School of Engineering, Computing and Mathematics

No abstract provided.


Autonomic Management Of Service Level Agreements In Cloud Computing, Stefan Edwin Karl Frey Jan 2021

Autonomic Management Of Service Level Agreements In Cloud Computing, Stefan Edwin Karl Frey

School of Engineering, Computing and Mathematics Theses

Autonomic Management of Service Level Agreements in Cloud Computing Cloud computing has been one of the major trending topics of recent years in the Information Technology (IT) industry. In contrary to the previous IT service delivery models, where all the services and resources were hosted locally, the idea behind cloud computing is to deliver computing resources or services on-demand over a network on an easy pay-per-use business model. This paradigm change included almost all areas of the modern IT landscape, be it the storage and sharing of data for example with services like Dropbox, Microsoft OneDrive or Google Drive or …


Developmental Neurorobotics Models Of Counting And Numerosity Judgment, Leszek Pecyna Jan 2021

Developmental Neurorobotics Models Of Counting And Numerosity Judgment, Leszek Pecyna

School of Engineering, Computing and Mathematics Theses

This thesis presents novel developmental robotics models of number cognition which take into account the embodied basis of this process. The ability to perceive quantity is undoubtedly crucial for both humans and animals. Nowadays, automation is becoming increasingly important in society; it seems that the way, similar to humans, to perceive and process numbers is one of the pressing issues for the future of robotics. This is important in the context of proper interaction between robots and humans which requires machines - at least on some level - to understand complex/abstract words such as number names. This thesis takes into …