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

Engineering Commons™

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

Technological University Dublin

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1171 - 1200 of 4606

Full-Text Articles in Engineering

Mode Analysis And Applications Of Three-Layer Step-Index And Depressed-Core Optical Fibers, Xiaokang Lian Oct 2020

Mode Analysis And Applications Of Three-Layer Step-Index And Depressed-Core Optical Fibers, Xiaokang Lian

Doctoral

Optical fibersplay important roles in telecommunication, imaging, sensing, lasers and amplifiers. The rapid development of fiberopticsover the past decades has beenunderpinnedbyvarious designs of the optical fibers and bythe rapid improvement of the understanding of the waveguiding mechanismsand associated models. According to the cross-section refractive index distribution, optical fibers can be generally classified into four basic types: two-layer step-index fiber, three-layer step-index fiber, three-layer depressed-core fiber and hollow-core fiber.Among these four basic fibertypes,the modeproperties and the applications of the three-layer step-index and depressed-core fibers have notbeensufficiently investigated. This thesis presents a detailedmode analysis in three-layer step-index and depressed-core fibers and their …


Cleanpage: Fast And Clean Document And Whiteboard Capture, Jane Courtney Oct 2020

Cleanpage: Fast And Clean Document And Whiteboard Capture, Jane Courtney

Articles

The move from paper to online is not only necessary for remote working, it is also significantly more sustainable. This trend has seen a rising need for the high-quality digitization of content from pages and whiteboards to sharable online material. However, capturing this information is not always easy nor are the results always satisfactory. Available scanning apps vary in their usability and do not always produce clean results, retaining surface imperfections from the page or whiteboard in their output images. CleanPage, a novel smartphone-based document and whiteboard scanning system, is presented. CleanPage requires one button-tap to capture, identify, crop, and …


An Outline Of The Roles Of The Principle Participants In The ‘Traditional’ Construction Procurement Process, Tony Cunningham Sep 2020

An Outline Of The Roles Of The Principle Participants In The ‘Traditional’ Construction Procurement Process, Tony Cunningham

Other Resources

The construction industry is a complex and fragmented industry comprised of a wide range of participants. This study examines the roles of principle participants in the process, and focusses on the role of the client, the contracting organisation, the architect and design and management professionals including the quantity surveyor. Other parties who are indirectly involved in the industry including the regulatory authorities, the wider property sector and end users are commented upon, but are not examined in great detail. The study has identified that effective teamwork is crucial to successfully achieving the goals of delivering the project safely, to the …


Stacked Convolutional Recurrent Auto-Encoder For Noise Reduction In Eeg, Eoghan Keegan Sep 2020

Stacked Convolutional Recurrent Auto-Encoder For Noise Reduction In Eeg, Eoghan Keegan

Dissertations

Electroencephalogram (EEG) can be used to record electrical potentials in the brain by attaching electrodes to the scalp. However, these low amplitude recordings are susceptible to noise which originates from several sources including ocular, pulse and muscle artefacts. Their presence has a severe impact on analysis and diagnoses of brain abnormalities. This research assessed the effectiveness of a stacked convolutional-recurrent auto-encoder (CR-AE) for noise reduction of EEG signal. Performance was evaluated using the signal-to-noise ratio (SNR) and peak signal-to-noise ratio (PSNR) in comparison to principal component analysis (PCA), independent component analysis (ICA) and a simple auto-encoder (AE). The Harrell-Davis quantile …


Sustainable Development Competencies For Achieving The Sdgs: Engineering Students And Industry Requirements, Klara Kövesi, Brad Tabas, Christiane Gillet, Una Beagon, Brian Bowe Sep 2020

Sustainable Development Competencies For Achieving The Sdgs: Engineering Students And Industry Requirements, Klara Kövesi, Brad Tabas, Christiane Gillet, Una Beagon, Brian Bowe

Conference Papers

This paper will provide an insight into how French engineering students and employers perceive the competencies needed to meet the UN Sustainable Development Goals (SDG). It draws on the findings of two exploratory focus group studies carried out in the context of the A-STEP 2030 European Project. Our results indicate significant differences in the awareness of sustainability goals among respondents, but a relatively high level of convergence around the skills and competencies that appear most necessary for attaining sustainable development. The respondents considered that technical knowledge and skills were adequately included within French engineering school curricula, yet they felt that …


Discover Influential Mental Workload Attributes Impacting Learners Performance In Third-Level Education, Amisha Mehta Sep 2020

Discover Influential Mental Workload Attributes Impacting Learners Performance In Third-Level Education, Amisha Mehta

Dissertations

Human Mental Workload is an intervening variable and a fundamental concept in the discipline of Ergonomics. It is deduced from variations in performance. High or low mental workload leads to hampering of performance. Mental workload in an educational setting has been extensively researched. It is applied in instructional design but it is obscure as to which factors are majorly driving mental workload in learners. This dissertation investigates the importance of the features used in the the NASA-Task Load Index mental workload assessment instrument and their impact on the performance of learners as assessed by multiple-choice tests conducted in classrooms of …


Bs News September/October Sep 2020

Bs News September/October

Building Services Engineering

No abstract provided.


The Entanglement Of Influential Technology Channels In Practice And Design, Ciarán O'Leary Sep 2020

The Entanglement Of Influential Technology Channels In Practice And Design, Ciarán O'Leary

Doctoral

Design for academic practice is an important phenomenon in Higher Education. This is the practice through which informal, non-professional designers operating in a variety of roles in academic institutions carry out the design of systems, resources, activities and processes that are intended to enhance academic practice. Despite its importance, the area has not received sufficient attention in studies of academic practice, quality enhancement and digital transformation. This thesis argues that the absence of insight into how designers for academic practice engage with digital technology in their design practice contributes to the mismatch between the ambitions for digital transformation in higher …


Social Enterprise And Sustainability: Key Factors That Lead To The Successful Establishment Of Sustainable Development Initiatives In Ireland, Gerard Doyle Sep 2020

Social Enterprise And Sustainability: Key Factors That Lead To The Successful Establishment Of Sustainable Development Initiatives In Ireland, Gerard Doyle

Doctoral

International research points to the positive impact that social enterprises with an environmental focus (also referred to as sustainable development initiatives) perform in the transition to low carbon societies. This thesis examines the capacities required for the establishment and maintenance of sustainable development initiatives in Ireland. The thesis is based on five pieces of research which are either published in international peer-reviewed publications or of a publishable standard. One of the published pieces provides an explanatory framework addressing the reasons why the social enterprise sector in Ireland is less developed than in a number of European countries, details a number …


Detection Of Software Vulnerability Communication In Expert Social Media Channels: A Data-Driven Approach, Andrei Lima Queiroz Sep 2020

Detection Of Software Vulnerability Communication In Expert Social Media Channels: A Data-Driven Approach, Andrei Lima Queiroz

Doctoral

Conceptually, a vulnerability is: "A flaw or weakness in a system’s design, implementation,or operation and management that could be exploited to violate the system’s security policy".Some of these flaws can go undetected and exploited for long periods of time after soft-ware release. Although some software providers are making efforts to avoid this situ-ation, inevitability, users are still exposed to vulnerabilities that allow criminal hackersto take advantage. These vulnerabilities are constantly discussed in specialised forumson social media. Therefore, from a cyber security standpoint, the information found inthese places can be used for countermeasures actions against malicious exploitation ofsoftware. However, manual inspection …


The Irish Construction Industry’S State Of Readiness For A Bim Mandate In 2020, Barry Mcauley, Alan V. Hore, Roger P. West Aug 2020

The Irish Construction Industry’S State Of Readiness For A Bim Mandate In 2020, Barry Mcauley, Alan V. Hore, Roger P. West

Conference papers

It was recently announced that a BIM mandate for the Irish public sector is not imminent, suggesting that the sector is not yet ready for what such a mandate implies. Following on from a forward-looking BIM Roadmap for Ireland in 2017 and the publication by the authors of a detailed BIM in Ireland study in 2017 and 2019, what is the actual state of readiness for a more general BIM mandate in Ireland? This paper will review recent publications, seminars and industry initiatives on this topic of interest supported by an online survey to assess the current state of readiness …


Thermodynamic Cement Hydration Modelling Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer Aug 2020

Thermodynamic Cement Hydration Modelling Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

Thermodynamics have been successfully applied to the field of cement hydration science to predict the formation of phase assemblages and pore solution chemistry. For any cement hydration model to be accepted, it must provide accurate forecasts of which solids may form and how the cement will dissolve over time. This is particularly important for the ongoing development of new sustainable cements and understanding their hydration behaviour in service. HYDCEM is a cement hydration model that simulates volumetric changes of cement and gypsum dissolution and product growth that, up to now, assumed which solids would form. In order to improve its …


Effects Of Accelerated Carbonation Curing On Co2 Sequestration And On The Compressive Strength Of Concrete Masonry Units, Barry Gilroy, Leon Black, David Thompson, Ronan Hogan, Niall Holmes Aug 2020

Effects Of Accelerated Carbonation Curing On Co2 Sequestration And On The Compressive Strength Of Concrete Masonry Units, Barry Gilroy, Leon Black, David Thompson, Ronan Hogan, Niall Holmes

Conference papers

The global consumption of Portland cement has risen to over 4 billion tonnes per annum. Its manufacture is energy and carbon intensive and approximately 900 kg of CO2 is emitted into the atmosphere for each tonne of Portland cement produced. The International Energy Agency (IEA) roadmap sets out a goal to reduce emissions due to cement production to 18 % below 2006 levels by 2050. Concrete has the potential to re-absorb CO2 by the process of carbonation, where it reacts with CaO in the concrete to form calcium carbonate. Accelerated carbonation curing (ACC) is a technique for curing fresh concrete …


The Use Of Three-Dimensional Conjugate Cfd To Enhance Understanding Of, And To Verify, Multi-Modal Heat Transfer In Dynamic Laboratory Test Walls, Rakshit D. Muddu, Timothy Patrick O'Leary, Ronan Hogan, Anthony James Robinson, Aimee Byrne Aug 2020

The Use Of Three-Dimensional Conjugate Cfd To Enhance Understanding Of, And To Verify, Multi-Modal Heat Transfer In Dynamic Laboratory Test Walls, Rakshit D. Muddu, Timothy Patrick O'Leary, Ronan Hogan, Anthony James Robinson, Aimee Byrne

Articles

This work describes the use of conjugate computational fluid dynamics (C-CFD) to simulate controlled laboratory based dynamic heat transfer tests on building components. This study proposes that conjugate CFD simulation can be used to evaluate the influence of combined convective and conductive heat transfer in multi-state building components. To this end, a solid wall and cavity wall were tested with a Calibrated Hotbox and subject to variable temperature conditions leading to combined convective and conductive heat transfer. The varying temperature of the heat source was monitored and used as the input boundary condition in the simulation model, which included a …


Predicting Mortar Compressive Strength Using Hydcem, Ewoma Ogoro, Niall Holmes, Denis Kelliher, Mark Tyrer Aug 2020

Predicting Mortar Compressive Strength Using Hydcem, Ewoma Ogoro, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

The compressive strength of mortar is a significant property that will influence its performance in concrete or masonry. Being able to accurately model and predict the mortar compressive strength would be of great benefit to suppliers and end users alike that could possibly reduce the need for multiple physical testing. A section of the original HYDCEM cement hydration model (amoungst others) has been partitioned to focus on predicting the compressive strength of Portland cement and cement-limestone mortars, entitled HYDCEM_CompressiveStrength. The model uses the cement/binder oxide composition along with other inputs to predict the compressive strength development over time. This paper …


Characterization And Performance Of Cement-Based Thermoelectric Materials, Ruchita Jani, Niall Holmes, Roger P. West, Kevin Gaughan, Xiaoli Liu, Esther Orisakwee, Conrad Johnston, Ming Qu, Jorge Kohanoff, Lorenzo Stella, Hongxi Yin Aug 2020

Characterization And Performance Of Cement-Based Thermoelectric Materials, Ruchita Jani, Niall Holmes, Roger P. West, Kevin Gaughan, Xiaoli Liu, Esther Orisakwee, Conrad Johnston, Ming Qu, Jorge Kohanoff, Lorenzo Stella, Hongxi Yin

Conference papers

Thermoelectric materials enable direct conversion of thermal energy to electricity. Ambient heat energy harvesting could be an effective route to convert buildings from being energy consumers to energy harvesters, thus making them more sustainable. There exists a relatively stable temperature gradient (storing energy) between the internal and external walls of buildings which can be utilized to generate meaningful energy (that is, electricity) using the thermoelectric principle. This could ultimately help reduce the surface temperatures and energy consumption of buildings, especially in urban areas. In this paper, ongoing work on developing and characterizing a cement-based thermoelectric material is presented. Samples are …


Measurement And Simulation Of Head Impacts In Mixed Martial Arts, Aidan Meagher Aug 2020

Measurement And Simulation Of Head Impacts In Mixed Martial Arts, Aidan Meagher

Doctoral

No abstract provided.


Bim Research In Irish Academic Institutions 2015-19, Barry Mcauley, Alan V. Hore, Roger P. West Aug 2020

Bim Research In Irish Academic Institutions 2015-19, Barry Mcauley, Alan V. Hore, Roger P. West

Conference papers

The use of BIM in the Irish construction industry has become pervasive in the last decade and it is an essential element in improving productivity in the market. The developments in BIM education and training in supporting the increase in Ireland’s BIM maturity has been well documented in recent years, principally through the proceedings of the BIM Gatherings and the BIM in Ireland 2017 and 2019 reviews. Similarly, the public and private sectors have been surveyed to establish their readiness for digital transformation on their BIM journey. However, BIM research undertaken by Irish academics, while individually strong, has not been …


Towards A Sociotechnical Reconfiguration Of Engineering And An Education For Ethics : A Critical Realist Investigation Into The Patterns Of Education And Accreditation Of Ethics In Engineering Programmes In Ireland, Diana Adela Martin Jul 2020

Towards A Sociotechnical Reconfiguration Of Engineering And An Education For Ethics : A Critical Realist Investigation Into The Patterns Of Education And Accreditation Of Ethics In Engineering Programmes In Ireland, Diana Adela Martin

Doctoral

The focus of this thesis is on the provision and evaluation of ethics in engineeringprogrammes in Ireland, by placing this examinationin the wider cultural context of engineering education.The study benefitted from the support of the national accrediting body Engineers Ireland, and included 23 engineering programmes from 2 institutes of technology and 4 universities in Ireland which underwent accreditation between 2017-2019.By using a Critical Realistframe, the study undertakes a multi-layeredinvestigation of the engineering education system that takes into consideration theindividual level of single agents such as instructors and evaluators, the institutional level comprised of engineering programmes, as well as the policy …


Bs News July/August Jul 2020

Bs News July/August

Building Services Engineering

No abstract provided.


Red Blood Cell Dynamics On Non-Uniform Grids Using A Lattice Boltzmann Flux Solver And A Spring-Particle Red Blood Cell Model, Brendan Walsh Jul 2020

Red Blood Cell Dynamics On Non-Uniform Grids Using A Lattice Boltzmann Flux Solver And A Spring-Particle Red Blood Cell Model, Brendan Walsh

Doctoral

The Computational Haemodynamics Research Group (CHRG) in Technological University Dublin is developing a computational fluid dynamics (CFD) software package aimed specifically at physiologically-realistic modelling of blood flow. A physiologically-realistic model of blood flow involves calculating the deformation of individual red blood cells (RBCs) and the contribution of this deformation to the overall blood flow. The CHRG has developed an enhanced spring-particle RBC structural model that is capable of modelling the full stomatocyte-discocyteechinocyte (SDE) transformation. This RBC model, incorporated into a fluid dynamics solver, will provide a physiologically-realistic blood flow model. In this work the overall plasma flow is modelled using …


Long-Term Durability Of Solar Photovoltaic Modules, Chibuisi Chinasaokwu Okorieimoh, Brian Norton Jun 2020

Long-Term Durability Of Solar Photovoltaic Modules, Chibuisi Chinasaokwu Okorieimoh, Brian Norton

Conference papers

Solar photovoltaic (PV) panels experience long-term performance degradation resulting in lower like-per-like efficiencies and performance ratios when compared with their initial performance. Manufacturers of solar photovoltaic modules usually guarantee the life span for more than 20 years. It is therefore necessary to track and mitigate degradation of PV modules over this period to satisfy such guarantees and beyond this period to identify maintenance and repair requirements. Degradation of solar PV modules makes them less efficient, less reliable and, ultimately, inoperative. This paper reviews relevant literature to discuss:

  • Causes of efficiency reductions in photovoltaic cells

  • Ways to achieve long-term durability of …


Moving Targets: Addressing Concept Drift In Supervised Models For Hacker Communication Detection, Susan Mckeever, Brian Keegan, Andrei Quieroz Jun 2020

Moving Targets: Addressing Concept Drift In Supervised Models For Hacker Communication Detection, Susan Mckeever, Brian Keegan, Andrei Quieroz

Conference papers

Abstract—In this paper, we are investigating the presence of concept drift in machine learning models for detection of hacker communications posted in social media and hacker forums. The supervised models in this experiment are analysed in terms of performance over time by different sources of data (Surface web and Deep web). Additionally, to simulate real-world situations, these models are evaluated using time-stamped messages from our datasets, posted over time on social media platforms. We have found that models applied to hacker forums (deep web) presents an accuracy deterioration in less than a 1-year period, whereas models applied to Twitter (surface …


What The Post-Coronavirus University Will Look Like, Thomas Power Jun 2020

What The Post-Coronavirus University Will Look Like, Thomas Power

Articles

The opportunity of a crisis is that it forces an industry to re-examine its policies and practices. Since the coronavirus pandemic university leadership teams have been forced to re-examine its policies and practices on teaching, learning, research and funding.


Share Buybacks And Income Inequality, Thomas Power Jun 2020

Share Buybacks And Income Inequality, Thomas Power

Articles

Should you care what companies do with their profits? Two U.S. democratic senators, Chuck Schumer and Bernie Sanders, in an article in the New York Times, argue that we should all care because what companies do with their profits can damage the economy and jobs.


A Proactive-Restoration Technique For Sdns, Ali Malik, Ruairí De Fréin Jun 2020

A Proactive-Restoration Technique For Sdns, Ali Malik, Ruairí De Fréin

Conference papers

Failure incidents result in temporarily preventing the network from delivering services properly. Such a deterioration in services called service unavailability. The traditional fault management techniques, i.e. protection and restoration, are inevitably concerned with service unavailability due to the convergence time that is required to achieve the recovery when a failure occurs. However, with the global view feature of software-defined networking a failure prediction is becoming attainable, which in turn reduces the service interruptions that originated by failures. In this paper, we propose a proactive restoration technique that reconfigure the vulnerable routes which are likely to be affected if the …


Intelligent Sdn Traffic Classification Using Deep Learning: Deep-Sdn, Ali Malik, Ruairí De Fréin, Mohammed Al-Zeyadi, Javier Andreu-Perez Jun 2020

Intelligent Sdn Traffic Classification Using Deep Learning: Deep-Sdn, Ali Malik, Ruairí De Fréin, Mohammed Al-Zeyadi, Javier Andreu-Perez

Conference papers

Accurate traffic classification is fundamentally important for various network activities such as fine-grained network management and resource utilisation. Port-based approaches, deep packet inspection and machine learning are widely used techniques to classify and analyze network traffic flows. However, over the past several years, the growth of Internet traffic has been explosive due to the greatly increased number of Internet users. Therefore, both port-based and deep packet inspection approaches have become inefficient due to the exponential growth of the Internet applications that incurs high computational cost. The emerging paradigm of software-defined networking has reshaped the network architecture by detaching the control …


Trades And Apprenticeship Survey 2020: Focus On Wet Trades, Roisin Murphy Jun 2020

Trades And Apprenticeship Survey 2020: Focus On Wet Trades, Roisin Murphy

Reports

CIF commissioned the Trades and Apprenticeship Survey 2020 – Focus on Wet Trades report to investigate the causes and implications of the low numbers entering wet trades (Bricklaying, floor and wall tiling, Painting and Decorating and Plastering). The objective for commissioning expert research was to fully understand whether the current model is appropriate for the sector or simply requires a new approach.

The research, carried out by Dr. Róisín Murphy, undertook a multi-stakeholder analysis, to determine the causes and challenges facing wet trades and apprenticeship in Ireland.

The report proposes six recommendations and addresses an Apprenticeship model review, Education and …


Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin Jun 2020

Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin

Conference papers

Commercially recorded music since the 1950s has been mixed down from many input sound sources to a two- channel reproduction of these sources. The effect of this approach is to assign sources to locations in a stereo field using a pan- position for each source. The Adress algorithm is a popular way of extracting individual music sound sources from a stereo mixture. A drawback of the Adress algorithm is that when time- frequency components in the stereo mixture are shared between two or more sources, calculating the inter-aural intensity scaling parameter for each source for that time-frequency component is challenging. …


New Robust Lpc-Based Method For Time-Resolved Morphology Of High-Noise Multiple Frequency Signals, Jin Xu, Ruairí De Fréin, Mark Davis Jun 2020

New Robust Lpc-Based Method For Time-Resolved Morphology Of High-Noise Multiple Frequency Signals, Jin Xu, Ruairí De Fréin, Mark Davis

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 low Signal-to-noise Ratio (SNR) signals comprising multiple frequency components. One of the challenges of the time-resolved spectral method is that they are limited by the Heisenberg-Gabor uncertainty principle. Consequently, there is a trade-off between the temporal and spectral resolution. Most of the previous studies are time-averaged methods. The proposed method is a parameterisation method which can directly extract the dominant formants. The method is based on a z-plane analysis of the poles …