Engineering Commons^™

Confinement Of Monolithic Stationary Phases In Targeted Regions Of 3d-Printed Titanium Devices Using Thermal Polymerization, Marta Passamonti, Ischa L. Bremer, Suhas H. Nawada, Sinead A. Currivan, Andrea F.G. Gargano, Peter J. Schoenmakers

Articles

Abstract

In this study, we have prepared thermally initiated polymeric monolithic stationary phases within discrete regions of 3D-printed titanium devices. The devices were created with controllable hot and cold regions. The monolithic stationary phases were first locally created in capillaries inserted into the channels of the titanium devices. The homogeneity of the monolith structure and the interface length were studied by scanning a capacitively coupled conductivity contactless detector (C4D) along the length of the capillary. Homogeneous monolithic structures could be obtained within a titanium device equipped with a hot and cold jacket connected to two water baths. The confinement method …

Microfluidic Flow Direction And Rate Vector Sensor Based On A Partially Gold-Coated Tfbg, Changyu Shen, Dejun Liu, Xiaokang Lian, Tingting Lang, Chunliu Zhao, Yuliya Semenova, Jacques Albert

Articles

In microfluidic chips applications, the monitoring of the rate and the direction of a microfluidic flow is very important. Here, we demonstrate a liquid flow rate and a direction sensor using a partially gold-coated tilted fiber Bragg grating (TFBG) as the sensing element. Wavelength shifts and amplitude changes of the TFBG transmission resonances in the near infrared reveal the direction of the liquid flowing along the fiber axis in the vicinity of the TFBG due to a nanoscale gold layer over part of the TFBG. For a device length of 10 mm (and a diameter of 125 µm for easy …

In Situ Image Processing And Data Binning Strategy For Particle Engineering Applications, Toufic El Arnaout, Patrick J. Cullen

Articles

Crystallization control can be improved through real-time monitoring technologies. Here, a workflow is demonstrated on rapid batch cooling crystallization of L-glutamic acid. First, in situ images were generated using video microscopy sensors and analyzed, by employing a single, rapid macro code to extract particle data descriptors. A binning procedure (over time) was performed, where every data point represented the counts of particles within a specific size or shape range per 100 images. This binning method was found more informative in tracking of the populations compared to whole image averages or individual particle datapoints. This study provides a step-by-step guide towards …

Cognitive Performance In Midlife Type 2 Diabetes: Results Form The Enbind Study, A. H. Dyer, L. Mckenna, G. Gamage, N. M. Bourke, Isabelle Killane, M. Widdowson, C. P. Woods, J. Gibney, R. Reilly, D. O'Neill, S. P. Kennelly

Articles

Aims: To establish the impact of uncomplicated type 2 diabetes on cognitive and neuropsychological performance in midlife. Methods: We performed a cross-sectional study of middle-aged adults with uncomplicated type 2 diabetes and a cohort of healthy control participants. General cognition was assessed using the Montreal Cognitive Assessment test and neuropsychological assessment was undertaken using a detailed neuropsychological assessment battery. Results: A total of 152 participants (102 with type 2 diabetes and 50 controls) were recruited (mean age 52 ± 8 years, 51% women). Participants with midlife type 2 diabetes were more than twice as likely to make an error on …

Comparison Of Rans Turbulence Models In Predicting Wake Development In A 2-Dimensional Actuator Disk Model, Chee Meng Pang, David Kennedy, Fergal O'Rourke Dr

Conference Papers

One of the most popular methodologies used to predict the wake of a tidal stream turbine (TST) is the RANS turbulence models coupled with the actuator disk method. This methodology has been widely adopted in the in the wind industry, since the mid-1990s, to predict wake development of wind turbines. Moreover, the reason for its popularity is its capability to give accurate results at an affordable computational cost, and the application of 2-dimensional actuator disk approach could further reduce the computational cost. In this paper, a number of RANS turbulence models represented by a porous disk were used to simulate …

Accounting For The Local Field When Determining The Dielectric Loss Spectra Of Metals In The Region Of The Frequencies Of Volume, Surface And Localized Plasmon Oscillations, Tatiana Perova, Igor Shaganove, Kevin Berwick

Articles

The optical constant of bulk metal is used to determine the dispersion of the local field under one-dimensional (1D), two-dimensional (2D) and three-dimensional (3D) confinement. 3D confinement, expressed as ε mic 2 (ω3D), corresponds to the dielectric loss spectra of spherical particles with a diameter, d, much less than the wavelength of the beam used to measure the spectrum (d << λ). Excellent agreement with the results of Mie theory and experimental data for solid colloids within alkali halide crystals was observed. The function expressed as ε mic 2 (ω1D) allows the measurement of spectral micro-characteristics in the frequency range of the longitudinal collective motion of the free electrons. This corresponds to the spectrum of dielectric losses of bulk plasma oscillations. The function ε mic 2 (ω2D) describes the spectra of the dielectric losses of surface plasma oscillations in thin metal films. It is shown that the peak positions of ε mic 2 (ω3D), ε mic 2 (ω2D) and ε mic 2 (ω1D) spectra for simple metals, viz. alkali metals as well as Al, Be, Mg, Ga, In, Sn and Si, are in agreement with experimental results from electron-energy-loss spectroscopy and various optical techniques.

Performance Investigation Of Peak Shrinking And Interpolating The Papr Reduction Technique For Lte-Advance And 5g Signals, Somayeh Mohammady, Ronan Farrell, David Malone, John Dooley

Articles

Orthogonal frequency division multiplexing (OFDM) has become an indispensable part of waveform generation in wideband digital communication since its first appearance in digital audio broadcasting (DAB) in Europe in 1980s, and it is indeed in use. As has been seen, the OFDM based waveforms work well with time division duplex operation in new radio (NR) systems in 5G systems, supporting delay-sensitive applications, high spectral efficiency, massive multiple input multiple output (MIMO) compatibility, and ever-larger bandwidth signals, which has demonstrated successful commercial implementation for 5G downlinks and uplinks up to 256-QAM modulation schemes. However, the OFDM waveforms suffer from high peak …

Self-Similar Pcosecond Pulse Compression For Supercontinuum Generation At Mid-Infrared Wavelength In Silicon Strip Waveguides, Yujun Cheng, Jinhui Yuan, Chao Mei, Feng Li, Zhe Kang, Binbin Yan, Xian Zhou, Qiang Wu, Kuiru Wang, Xinzhu Sang, Keping Long, Chongxiu Yu, Gerald Farrell

Articles

Self-similar pulse compression has important application in highly coherent supercontinuum (SC) generation. In this paper, we numerically present the mid-infrared self-similar picosecond pulse compression in a tapered suspended silicon strip waveguide, which is designed with exponentially decreasing dispersion profile along the direction of propagation. When the variation of the Kerr nonlinear coefficient ��(z), linear and nonlinear losses, higher-order nonlinearity, and higher-order dispersion are taken into consideration, the simulation result shows that a 1 ps input pulse centered at wavelength 2.8 μm could be self-similarly compressed to 47.06 fs in a 3.9-cm waveguide taper, along with a compression factor ��c of …

Applications Of Artificial Intelligence To Cryptography, Jonathan Blackledge, Napo Mosola

Articles

This paper considers some recent advances in the field of Cryptography using Artificial Intelligence (AI). It specifically considers the applications of Machine Learning (ML) and Evolutionary Computing (EC) to analyze and encrypt data. A short overview is given on Artificial Neural Networks (ANNs) and the principles of Deep Learning using Deep ANNs. In this context, the paper considers: (i) the implementation of EC and ANNs for generating unique and unclonable ciphers; (ii) ML strategies for detecting the genuine randomness (or otherwise) of finite binary strings for applications in Cryptanalysis. The aim of the paper is to provide an overview on …

Reformulating The Binary Masking Approach Of Adress As Soft Masking, Ruairí De Fréin

Articles

Binary masking forms the basis for a number of source separation approaches that havebeen successfully applied to the problem of de-mixing music sources from a stereo recording.A well-known problem with binary masking is that, when music sources overlap in the time-frequencydomain, only one of the overlapping sources can be assigned the energy in a particulartime-frequency bin. To overcome this problem, we reformulate the classical pan-pot source separationproblem for music sources as a non-negative quadratic program. This reformulation gives rise toan algorithm, called Redress, which extends the popular Adress algorithm. It works by definingan azimuth trajectory for each source based on …

A Wide Frequency Scanning Printed Bruce Array Antenna With Bowtie And Semi-Circular Elements, Zeeshan Ahmed, Patrick Mcevoy, Max Ammann

Articles

A printed edge-fed counterpart of the wire Bruce array antenna, for frequency scanning applications, is presented in this paper. The unit-cell of the proposed antenna consists of bowtie and semi-circular elements to achieve wide bandwidth from below 22 GHz to above 38 GHz with open-stopband suppression. The open-stopband suppression enables a wide seamless scanning range from backward, through broadside, to forward endfire. A sidelobe threshold level of −10 dB is maintained to evaluate efficient scanning performance of the antenna. The antenna peak realized gain is 15.30 dBi, and, due to its compact size, has the ability to scan from −64° …

Spectral Dependence Of Transmission Losses In High-Index Polymer Coated No-Core Fibers, Xiaokang Lian, Gerald Farrell, Qiang Wu, Wei Han, Changyu Shen, Youqiao Ma, Yuliya Semenova

Articles

A high-index polymer coated no-core fiber (PC-NCF) is effectively a depressed core fiber, where the light is guided by the anti-resonant, inhibited coupling and total internal reflection effects and the dispersion diagram shows periodic resonant and anti-resonant bands. In this paper, the transmission spectra of the straight and bent PC-NCFs (length > 5 cm) are measured and analyzed from a modal dispersion perspective. For the purpose of the study, the PC-NCFs are contained within a fiber hetero-structure using two single-mode fiber (SMF) pigtails forming a SMF-PC-NCF-SMF structure. The anti-resonance spectral characteristics are suppressed by the multimode interference in the PC-NCF with …

The Effect Of High Background And Dead Time Of An Ingaas/Inp Single-Photon Avalanche Photodiode On The Registration Of Microsecond Range Near-Infrared Luminescence, P. S. Parfenov, A. P. Litvin, D. A. Onishchuk, K. A. Gonchar, Kevin Berwick, A. V. Fedorov, A. V. Baranov

Articles

The effects of a high background count and a microsecond dead time interval on a gated InGaAs/InP single-photon avalanche photodiode (SPAD) during microsecond luminescence decay registration are discussed. It is shown that the background count rate of the SPAD limits its use for time-resolved and steady-spectral measurements, and that a “pile-up” effect appears in the microsecond range.

Carbon-Based Interlayers In Perovskite Solar Cells, Aleksandr P. Litvin, Xiaoyu Zhang, Kevin Berwick, Anatoly V. Fedorov, Weitao Zheng, Alexander V. Baranov

Articles

Perovskites are solution-processed, high-performance semiconductors of interest in low-cost photovoltaics. The interfaces between the perovskite photoactive layers and the top and bottom contacts are crucial for efficient charge transport and minimizing trapping. Control of the collection of charge carriers at these interfaces is decisive to device performance. Here, we review recent progress in the realization of efficient perovskite solar cells using cheap, easily processed, stable, carbon-based interlayers. Interface materials including graphene, carbon nanotubes, fullerenes, graphene quantum dots and carbon dots are introduced and their influence on device performance is discussed.

The Missing Parameter In Renewable Energy Power Quality Analysis, I.E. The Coefficient Of Variation: Case Study Of A 3-Mw On-Site Wind Turbine Project In Ireland, Tony Kealy

Articles

Businesses are employing distributed generation techniques, such as wind turbines, to decarbonise their electrical energy supply by reducing their dependence on fossil-fuel-generated energy. This study investigates the effectiveness of a company making a €3,500,000 investment in a 3-MW on-site wind turbine to supply some or all of their factory electrical loads. The results should benefit the investing company and other potential investors by evaluating the economic, environmental, and social outcomes of the investment. A case study methodology was used. The study found that the payback period was six and a half years, and the turbine installation benefited the environment by …

Ambiqual: Towards A Quality Metric For Headphone Rendered Compressed Ambisonic Spatial Audio, Miroslaw Narbutt, Jan Skoglund, Andrew Allen, Michael Chinen, Dan Barry, Andrew Hines

Articles

Spatial audio is essential for creating a sense of immersion in virtual environments. Efficient encoding methods are required to deliver spatial audio over networks without compromising Quality of Service (QoS). Streaming service providers such as YouTube typically transcode content into various bit rates and need a perceptually relevant audio quality metric to monitor users’ perceived quality and spatial localization accuracy. The aim of the paper is two-fold. First, it is to investigate the effect of Opus codec compression on the quality of spatial audio as perceived by listeners using subjective listening tests. Secondly, it is to introduce AMBIQUAL, a full …

Brexit Election: Forecasting A Conservative Party Victory Through The Pound Using Arima And Facebook's Prophet, James Usher, Pierpaolo Dondio

Conference papers

On the 30th October, 2019, the markets watched as British Prime Minister, Boris Johnson, took a massive political gamble to call a general election to break the Withdrawal Agreement stalemate in the House of Commons to “Get BREXIT Done”. The pound had been politically sensitive owing to BREXIT uncertainty. With the polls indicating a Conservative win on 4thDecember, 2019, the margin of victory could be observed through increases in the pound. The outcome of a Conservative party victory would benefit the pound by removing the current market turbulence. We look to provide a short-term forecast of the pound. Our approach …

Android Compcache Based On Graphics Processing Unit, Muder Almi'ani, Abdu Razaque, Saleh Atiewi, Mohammed Alweshah, Ayman Al-Dmour, Basel Magableh

Conference papers

Android systems have been successfully developed to meet the demands of users. The following four methods are used in Android systems for memory management: backing swap, CompCache, traditional Linux swap, and low memory killer. These memory management methods are fully functioning.
However, Android phones cannot swap memory into solid-state drives, thus slowing the processor and reducing storage lifetime. In addition, the compression and decompression processes consume additional energy and latency. Therefore, the CompCache requires an extension. An extended Android CompCache using a graphics processing unit to compress and decompress memory pages on demand and reduce the latency is introduced in …

Classification And Biological Identity Of Complex Nano Shapes, Luca Boselli, Hender Lopez, Wei Zhang, Qi Cai, Valeria A. Giannone, Jingji Li, Alirio Moura, João M. De Araujo, Jennifer Cookman, Valentina Castagnola, Yan Yan, Kenneth A. Dawson

Articles

Everywhere in our surroundings we increasingly come in contact with nanostructures that have distinctive complex shape features on a scale comparable to the particle itself. Such shape ensembles can be made by modern nano-synthetic methods and many industrial processes. With the ever growing universe of nanoscale shapes, names such as “nanoflowers” and “nanostars” no longer precisely describe or characterise the distinct nature of the particles. Here we capture and digitise particle shape information on the relevant size scale and create a condensed representation in which the essential shape features can be captured, recognized and correlated. We find the natural emergence …

A Framework For Sustainable Procurement Practice In The Irish Construction Industry, Duga Jamus Ewuga

Doctoral

The Architectural, Engineering and Construction (AEC) sector has been called upon to develop innovative strategies to drive sustainability. Despite the efforts and commitments made, their performance is still observed to be low, this has been linked to the low level of understanding of practitioners. Also noted was the lack of interest by firms due to the uncertainty of the benefits of committing to long term investments. Nevertheless, academic literature and reports have stated that firms nowadays utilise their procurement mechanism to drive their sustainability practice. However, there is a gap in understanding how construction firms adopt and embed sustainability in …

Dynamic Blood-Brain Barrier Regulation In Mild Traumatic Brain Injury, Eoin O'Keeffe, Eoin Kelly, Yuzhe Liu, Chiara Giordano, Eugene Wallace, Mark Hynes, Stephen Tiernan, Aidan Meagher, Chris Greene, Stephanie Hughes, Tom Burke, John Kealy, Niamh Doyle, Alison Hay, Michael Farrell, Gerald A. Grant, Alon Friedman, Ronel Veksler, Michael G. Molloy, James F. Meaney, Niall Pender, David Camarillo, Colin P. Doherty, Matthew Campbell

Articles

Whereas the diagnosis of moderate and severe traumatic brain injury (TBI) is readily visible on current medical imaging paradigms (magnetic resonance imaging [MRI] and computed tomography [CT] scanning), a far greater challenge is associated with the diagnosis and subsequent management of mild TBI (mTBI), especially concussion which, by definition, is characterized by a normal CT. To investigate whether the integrity of the blood-brain barrier (BBB) is altered in a high-risk population for concussions, we studied professional mixed martial arts (MMA) fighters and adolescent rugby players. Additionally, we performed the linear regression between the BBB disruption defined by increased gadolinium contrast …

Using Machine Learning Classification Methods To Detect The Presence Of Heart Disease, Nestor Pereira

Dissertations

Cardiovascular disease (CVD) is the most common cause of death in Ireland, and probably, worldwide. According to the Health Service Executive (HSE) cardiovascular disease accounting for 36% of all deaths, and one important fact, 22% of premature deaths (under age 65) are from CVD.

Using data from the Heart Disease UCI Data Set (UCI Machine Learning), we use machine learning techniques to detect the presence or absence of heart disease in the patient according to 14 features provide for this dataset. The different results are compared based on accuracy performance, confusion matrix and area under the Receiver Operating Characteristics (ROC) …

Energy Performance Certification: Misassessment Due To Assuming Default Heat Losses, Ciara Ahern, Brian Norton

Articles

Energy Performance Certificates (EPCs) are issued when dwellings are constructed, sold or leased in the EU. Where the cost of obtaining the required data is prohibitive, EPC assessors use nationally applicable default-values. To ensure that dwellings are not assigned a wrongly-higher EPC rating, a standardised thermal bridging transmittance coefficient (Y-value) is typically adopted for all existing dwellings while worst-case overall heat loss coefficients (U-values) are used. Default U-values are applied to a specific building element type (roof, wall, floor etc.) based on building codes and regulations applicable at time of construction. Due to significant building fabric upgrades, default U-values are …

Factor Analysis Of Mixed Data (Famd) And Multiple Linear Regression In R, Nestor Pereira

Dissertations

In the previous projects, it has been worked to statistically analysis of the factors to impact the score of the subjects of Mathematics and Portuguese for several groups of the student from secondary school from Portugal.

In this project will be interested in finding a model, hypothetically multiple linear regression, to predict the final score, dependent variable G3, of the student according to some features divide into two groups. One group, analyses the features or predictors which impact in the final score more related to the performance of the students, means variables like study time or past failures. The second …

A-Step 2030 – New Research Project Presents A Picture Of The Skills Needed For Engineers To Solve The Sustainable Development Goals (Sdgs)., Una Beagon

Articles

Communication and Technical Skills will still be the most important attributes required of engineers in the future, according to a new study by the A-STEP 2030 Erasmus+ funded project. The project which is led by ENSTA Bretagne, France and has academic partners in TU Dublin, Metropolia University of Applied Sciences in Finland and Aalborg University in Denmark aims to develop innovative teaching approaches for engineering students which will attract a more diverse student body to the engineering profession.

Contextual Influences On Human Resources Development: Considerations And Evaluations On The Various External And Internal Factors That Shape And Influence Hrd In Organisations, Charles Alves De Castro

Articles

This article aims to briefly understand and evaluate the main external and internal factors that impact directly on human resources development area within the organisations, mainly related to multinational companies. Also, it discusses the various aspects and influences on HRD-(Human Resources Development) such as societal, organisational/local, global, that impacts on costs, environment, regulations, policies, culture, beliefs, technology and values. This research was carried out by way of a literature review. This is important to demonstrate, explain and evaluate the current existent literature about this specific theme covered in this article. Furthermore, through this review we compared previous research on HRD. …

Experimental Investigation Of Flow Pulsation Waveforms In Rectangular Mesochannels For High Heat Flux Electronics Cooling, Jaakko Mcevoy, Sajad Alimohammadi, Tim Persoons

Articles

The ever rising heat fluxes encountered in electronic devices present a challenging thermal engineering problem. Not only is heat transfer enhancement a goal but more recently control of the enhancement is desired, especially in large scale data facilities where the heated outlet coolant fluid may be of use. Flow pulsation is one of the most common active heat transfer enhancement methods studied across all heat sink sizes. While the effects of pulsation have been shown to increase heat transfer under certain conditions there is still disagreement upon its merit for practical applications, with the majority of previous research has been …

A Generalisable Bottom-Up Methodology For Deriving A Residential Stock Model From Large Empirical Databases, Ciara Ahern, Brian Norton

Articles

Specifying representative reference buildings as a prerequisite for calculating cost-optimal energy performance requirements for buildings and building elements. Appropriate characterisation is prerequisite data for an overall national building energy consumption model to produce valid outcomes. Energy Performance Certificates (EPCs) are issued in the EU, for dwellings whenever they are constructed, sold or leased. Where acquiring data for an EPC would be prohibitively costly, nationally applicable default-values are employed for the building envelope thermal transmittance coefficients. Significant levels of retrofits led to the default-values used now being higher than is typical in reality, leading to characterisations of reference dwellings based on …

Using Phenomenography In Engineering Education, Una Beagon

Other resources

A phenomenographic study of academic conceptions of professional skills in engineering programmes in Ireland

Thermal Energy Refurbishment Status Of The Irish Housing Stock, Ciara Ahern, Brian Norton

Articles

Energy Performance Certificates (EPCs) are issued for buildings constructed, sold or leased across the EU. Using a generalizable methodology this work exploits Ireland's EPC national dwelling stock database to determine the thermal refurbishment status of Ireland's housing stock. It is estimated in 2014 that; i) 58% of walls were insulated at a mean overall heat loss coefficient or U-value of 0.66 W/m²K, ii) 67% of roofs were insulated at a mean U-value 0.37 W/m²K, iii) 97% of windows were double-glazed, and iv) 53% of floors were insulated to a mean U-value of 0.59 W/m²K. …