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

Digital Commons Network™

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

2021

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 41491 - 41520 of 42406

Full-Text Articles in Entire DC Network

Towards An Improved Understanding Of Biogeochemical Processes Across Surface-Groundwater Interactions In Intermittent Rivers And Ephemeral Streams, Lluís Gómez-Gener Jan 2021

Towards An Improved Understanding Of Biogeochemical Processes Across Surface-Groundwater Interactions In Intermittent Rivers And Ephemeral Streams, Lluís Gómez-Gener

Articles

Surface-groundwater interactions in intermittent rivers and ephemeral streams (IRES), waterways which do not flow year-round, are spatially and temporally dynamic because of alternations between flowing, non-flowing and dry hydrological states. Interactions between surface and groundwater often create mixing zones with distinct redox gradients, potentially driving high rates of carbon and nutrient cycling. Yet a complete understanding of how underlying biogeochemical processes across surface-groundwater flowpaths in IRES differ among various hydrological states remains elusive. Here, we present a conceptual framework relating spatial and temporal hydrological variability in surface water-groundwater interactions to biogeochemical processing hotspots in IRES. We combine a review of …

Go to article

Socio-Economic Factors Associated With The Incidence Of Shiga-Toxin Producing Escherichia Coli (Stec) Enteritis And Cryptosporidiosis In The Republic Of Ireland, 2008–2017, Eiimear Cleary, Martin Boudou, Coilín Oscar Óhaiseadha, Patricia Garvey, Paul Mckeown, Jean O'Dwyer, Paul Hynds Jan 2021

Socio-Economic Factors Associated With The Incidence Of Shiga-Toxin Producing Escherichia Coli (Stec) Enteritis And Cryptosporidiosis In The Republic Of Ireland, 2008–2017, Eiimear Cleary, Martin Boudou, Coilín Oscar Óhaiseadha, Patricia Garvey, Paul Mckeown, Jean O'Dwyer, Paul Hynds

Articles

The Republic of Ireland (ROI) currently reports the highest incidence rates of Shiga-toxin producing Escherichia coli (STEC) enteritis and cryptosporidiosis in Europe, with the spatial distribution of both infections exhibiting a clear urban/rural divide. To date, no investigation of the role of socio-demographic profile on the incidence of either infection in the ROI has been undertaken. The current study employed bivariate analyses and Random Forest classification to identify associations between individual components of a national deprivation index and spatially aggregated cases of STEC enteritis and cryptosporidiosis. Classification accuracies ranged from 78.2% (STEC, urban) to 90.6% (cryptosporidiosis, rural). STEC incidence was …

Go to article

Development Of A Situational Judgement Test And An Assessment Of Its Efficacy As A Stimulus Of Metacognitive Behaviour In Engineering Students, Darren Carthy Jan 2021

Development Of A Situational Judgement Test And An Assessment Of Its Efficacy As A Stimulus Of Metacognitive Behaviour In Engineering Students, Darren Carthy

Doctoral

Metacognition entails the conscious evaluation and control of one's cognitive processes. This meta-level control of cognitive process is not essential for all activities, but in the domain of problem solving and the development of new expertise, conscious control of mental functioning is essential to success. Previous studies have shown a relationship between metacognitive knowledge & skills and student self-regulated learning, self-efficacy and more generally, with success in academic and non-academic endeavours; they represent critical skills for an aspiring engineer to possess for their future employability. Metacognition can be stimulated by allowing students to engage and reflect on the problem-solving process. …

Go to article

Preparing Teachers To Teach In K-12 Blended Environments: A Systematic Mapping Review Of Research Trends, Impact, And Themes, Cecil R. Short, Charles R. Graham, Theresa Holmes, Laura Oviatt, Hannah Bateman Jan 2021

Preparing Teachers To Teach In K-12 Blended Environments: A Systematic Mapping Review Of Research Trends, Impact, And Themes, Cecil R. Short, Charles R. Graham, Theresa Holmes, Laura Oviatt, Hannah Bateman

Faculty Publications

No abstract provided.

Go to article

Reducing Energy Demand In China And The United Kingdom: The Importance Of Energy Literacy, D. R.E. Cotton, J. Zhai, W. Miller, L. Dalla Valle, J. Winter Jan 2021

Reducing Energy Demand In China And The United Kingdom: The Importance Of Energy Literacy, D. R.E. Cotton, J. Zhai, W. Miller, L. Dalla Valle, J. Winter

School of Engineering, Computing and Mathematics

As the impacts of climate change become increasingly visible across the globe, awareness of the need for cleaner energy and demand reduction is growing. Energy literacy offers a strong potential for explaining and predicting energy-related behaviours, yet research and policies focused on this topic remain limited. In this study, energy literacy was measured in a sample of 2806 university students in the United Kingdom and China, in addition to their wider environmental attitudes using the New Ecological Paradigm scale. Findings indicate that energy literacy was relatively high overall, but there were significant differences between the knowledge, attitudes and behavioural intentions …

Go to article

An Univariate Extreme Sea State And Extreme Wind Speed For An Offshore Wind Turbine Off The South Coast Of Jamaica, A White, M Hann, J Miles, R Rawlinson-Smith, D Greaves Jan 2021

An Univariate Extreme Sea State And Extreme Wind Speed For An Offshore Wind Turbine Off The South Coast Of Jamaica, A White, M Hann, J Miles, R Rawlinson-Smith, D Greaves

School of Engineering, Computing and Mathematics

Offshore wind turbines are exposed to hydrodynamic and wind forces, which must be evaluated when designing them. One of the fundamental steps in the determination of these forces is the calculation of the return levels for significant wave height (Hs), peak wave period (Tp) and 10 m mean wind speed (u10). This paper explored the development of a univariate extreme value-analysis (EVA) sea state(Hs and Tp) and extreme wind speed, within the Caribbean Sea. These results will be used as inputs to a numerical model of a floating offshore wind turbine (FOWT). The Hs and wind speed were determined by …

Go to article

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.

Go to article

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 …

Go to article

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.

Go to article

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.

Go to article

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.

Go to article

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 …

Go to article

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, …

Go to article

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.

Go to article

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 …

Go to article

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 …

Go to article

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.

Go to article

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 …

Go to article

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 …

Go to article

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.

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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.

Go to article

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.

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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.

Go to article

First Prev Next Last