Engineering Commons^™

Leveraging Depolarization To Increase The Link Reliability For Wireless Sensors Operating In Hyper-Rayleigh Environments, Jeff Frolik, Vit Sipal, David J. Edwards

Articles

Wireless communications within enclosed environments such as aircraft and vehicles have been shown to experience fading with statistics that are worse than Rayleigh. Motivated by low-cost, low-complexity systems (e.g., wireless sensors) that may be deployed in such environments, this work explores the benefits of polarization diversity using very large data sets collected over a small area and over the 5-6 GHz band. The results also demonstrate that antennas capable of capturing depolarized signal components can significantly mitigate the harshest of fading environments.

Footwear Antennas For Body Area Telemetry, Domenico Gaetano, Patrick Mcevoy, Max Ammann, Jacinta Browne, Louise Keating, Frances Horgan

Articles

Antennas designed to link footwear sensors within body centric networks are introduced with two small UWB antennas, one directional and another quasi-omnidirectional. The radiating characteristics are evaluated for three positions on a sample sports shoe using a detailed simulation model and measurements with a homogenous foot phantom. Antenna performance is assessed for resilience to close proximity loading by the footwear materials and the phantom foot.

Small Wind Turbines In Turbulent (Urban) Environments: A Consideration Of Normal And Weibull Distributions For Power Prediction, Keith Sunderland, Thomas Woolmington, Jonathan Blackledge, Michael Conlon

Articles

The urban terrain and the associated morphological complexities therein, present significant challenges for the deployment of small wind turbines. In particular, a considerable amount of uncertainty is attributable to the lack of understanding concerning how turbulence within urban environments affects turbine productivity. Current wind turbine power output measurements (particularly for small/micro wind turbines) are based on an average wind speed over an observation period; with limited accountability of the variability of wind speed within the observation time frame. This paper however, presents two models that can instead accurately consider such wind speed variation and how it affects the turbine, based …

Feed‐In Tariff Design For Domestic Scale Grid‐Connected Pv Systems Using High Resolution Household Electricity Demand Data, Lacour Ayompe, Aidan Duffy

Articles

The advent of large samples of smart metering data allows policymakers to design Feed‐in Tariffs which are more targeted and efficient. This paper presents a methodology which uses these data to design FITs for domestic scale gridconnected PV systems in Ireland. A sample of 2,551 household electricity demand data collected at ½‐hourly intervals, electricity output from a 2.82 kWp PV system over the same time interval as well as PV system costs and electricity tariffs were used to determine the required FIT to make it worthwhile for the households to invest in the PV system. The methodology shows that it …

Dual Band Lte Planar Inverted-F Antenna For M2m Applications, Abraham Loutridis, Matthias John, Max Ammann

Articles

A Planar Inverted-F Antenna for M2M applications is presented. The antenna is located on a rectangular ground plane and operates across both LTE frequency bands (690-960 MHz) and (1710-2690 MHz). The low cost antenna has omni-directional characteristics. The efficiency is better than 86% in both bands and the gain is more than 1.38 dBi across the whole frequency range. A parametric study of key geometrical parameters is reported.

Experimental Microwave Breast Cancer Detection With Oil-On-Gelatin Phantom, Giuseppe Ruvio, Raffaele Solimene, Antonio Cuccaro, Jacinta Browne, Domenico Gaetano, Max Ammann

Articles

This paper presents a 2-D breast phantom which was realized with oil-in-gelatin materials for the evaluation of three different tumor detection methods operated in the microwave spectrum 1 – 3 GHz. A planar monopole antenna was used to scan the phantom in a multi-monostatic configuration across 36 angular locations. Results show a better performance of an Interferometric-MUSIC approach when compared to Non-coherent Migration and Wide Band MUSIC.

Dual Circularly-Polarized Patch Antenna Using Even And Odd Feed-Line Modes, Adam Narbudowicz, Xiulong Bao, Max Ammann

Articles

This paper proposes a new patch antenna with dual circularly polarized capability at 2.575 GHz. The design exploits the even and odd modes in a coplanar waveguide transmission line and enables simultaneous right- and left-handed circular polarization, with two individual excitation ports. A patch antenna is fed by multimode transmission line and the advantages and disadvantages are discussed. A prototyped antenna realized up to 20 dB isolation between ports with S21 < -10dB bandwidth of 87 MHz. Realized gains for the two modes of operation are 5.77 and 7.23 dBic. The proposed structure is compact and easy to manufacture.

Maximising Value Of Electrical Networks For Wave Energy Converter Arrays, Fergus Sharkey, Elva Bannon, Michael Conlon, Kevin Gaughan

Articles

Currently there are the beginnings of a commercial wave energy industry and the ultimate ambition will be to deploy Wave Energy Converters (WECs) in arrays, or wave farms, in a similar fashion to offshore wind. These arrays will require electrical networks to collect and export the generated electrical power to shore and onto the electrical grid. For large scale wind farms the inter-array and export electrical networks can represent more than 20% of the project’s capital expenditure. Submarine power cables account for a large proportion of this cost. The same is expected to be the same for WEC arrays.

This …

Analysis Of The Thermal Performance Of A Solar Water Heating System With Flat Plate Collectors In A Temperate Climate, Lacour Ayompe, Aidan Duffy

Articles

The thermal performance of a solar water heating system with 4 m² flat plate collectors in Dublin, Ireland is presented in this paper. The experimental setup consisted of a commercially available forced circulation domestic scale system fitted with an automated sub‐system that controlled hot water draw‐offs and the operation of an auxiliary immersion heater. The system was tested over a year and the maximum recorded collector outlet fluid temperature was 70.4 ^oC while the maximum water temperature at the bottom of the hot water tank was 59.9 ^oC. The annual average daily energy collected was 19.6 MJ/d, …

Single-Mode Tunable Laser Emission In The Single-Exciton Regime From Colloidal Nanocrystals, Christos Grivas, Chunyong Li, Peristera Andreakou, Pengfei Wang, Ming Ding, Gilberto Brambilla, Liberato Manna, Pavlos Lagoudakis

Articles

Whispering-gallery-mode resonators have been extensively used in conjunction with different materials for the development of a variety of photonic devices. Among the latter, hybrid structures, consisting of dielectric microspheres and colloidal core/shell semiconductor nanocrystals as gain media, have attracted interest for the development of microlasers and studies of cavity quantum electrodynamic effects. Here we demonstrate single-exciton, single-mode, spectrally tuned lasing from ensembles of optical antenna-designed, colloidal core/shell CdSe/CdS quantum rods deposited on silica microspheres. We obtain singleexciton emission by capitalizing on the band structure of the specific core/shell architecture that strongly localizes holes in the core, and the two-dimensional quantum …

Resource-Induced Voltage Flicker For Wave Energy Converters – Assessment Tools, Fergus Sharkey, Joe Macenri, Elva Bannon, Michael Conlon, Kevin Gaughan

Articles

For wave energy converters, the input resource has a typical period of 5–20 s depending on the site location and dominant seastates. Wave energy converters generally produce mechanical power twice per wave cycle and therefore depending on the storage available, the electrical power output has half the period of the input resource. These regular power changes induce a voltage change at the point of connection (POC) which is proportional to the amplitude of the power change and at the same frequency. Therefore the coupling of the input resource to the output power of a wave energy converter will cause voltage …

Footwear-Centric Body Area Network With Directional Uwb Antenna, Domenico Gaetano, Vit Sipal, Patrick Mcevoy, Max Ammann, C Brannigan, Louise Keating, Frances Horgan

Articles

A footwear-centric body area network employing a directional antenna is compared with waist-centric systems using omnidirectional and directional antennas. The impact of body movements on path gain is analysed for two bands at 3.99 GHz and 7.99 GHz. The path gain and data rate results demonstrate that footwear-centric configurations are equivalent or better than waist-centric body area networks.

Adaptive Ofdm For Wireless Interconnect In Confined Enclosures, Vit Sipal, Javier Gelabert, Christopher J. Stevens, Ben Allen, David Edwards

Articles

This letter considers and recommends OFDM with adaptive subcarrier modulation as a suitable candidate for wireless UWB communication in computer chassis. A rigorous measurement campaign studies the guaranteed spectral efficiency. It concludes that enhancement of the existing WiMedia OFDM systems with a bandwidth of 528 MHz in order to support adaptive OFDM would enable data-rates above 1 Gbps over short ranges, i.e. the spectral efficiency would be doubled. Moreover, the guaranteed spectral efficiency is shown to increase with bandwidth, i.e. the guaranteed data-rate increases better than linearly with bandwidth.

Kinetics Of Tomato Peroxidase Inactivation By Atmospheric Pressure Cold Plasma Based On Dielectric Barrier Discharge, Patrick Cullen, Shashi Pankaj, N. Misra

Articles

Atmospheric pressure cold plasma technology is an emerging nonthermal food technology for microbiological decontamination of food and bio-materials. This study demonstrates the applicability of in-package cold plasma technology as a novel means to inactivation of enzymes. The kinetics of inactivation of tomato peroxidase as a model enzyme was studied at 30, 40 and 50kV, for up to 5’ of atmospheric air dielectric barrier discharge plasma treatments. The enzyme activity was found to decrease with both treatment time and voltage, the former variable exhibiting a more pronounced effect. Kinetic models viz. first-order, Weibull and logistic models were fitted to the experimentally …

Comparison Of Non-Coherent Linear Detection Algorithms Applied To A 2-D Numerical Breast Model, Giuseppe Ruvio, Raffaele Solimene, Antonio Cuccaro, Max Ammann

Articles

A comparative analysis of an imaging method based on a multifrequency Multiple Signal Classification (MUSIC) approach against two common linear detection algorithms based on noncoherent migration is made. The different techniques are tested using synthetic data generated through CST Microwave Studio and a phantom developed from MRI scans of a mostly fat breast. The multifrequency MUSIC approach shows an overall superior performance compared to the noncoherent techniques. This letter reports that this highly performing algorithm does not require any antenna calibration or phase response estimation and allows the use of efficient and complex antenna geometries without difficult algorithm redefinitions.

Engineering Performance Of A New Siloxane-Based Corrosion Inhibitor, Niall Holmes, R. O'Brien, P. A. M. Basheer

Articles

This paper presents an evaluation of a new non-toxic corrosion inhibitor on selected engineering properties of concrete mixes with different cementitious materials following a corrosion and durability study on concrete samples. Corrosion inhibitors consist of powders or solutions which are added to concrete when mixed to prevent or delay corrosion of steel by their reaction with ferrous ions to form a stable and passive ferric oxide film on the steel surface. The new inhibitor functions slightly differently and its corrosion inhibition effect is due to the formation of a siloxane coating on the steel surface. Therefore, the performance of the …

Lean Integrated Design And Production: A Contractor's Perspective, Fiacra Mcdonnell

Articles

The scenario I have chosen for my paper concentrates on my experiences while employed as a senior estimator with Aidan Elliott Construction Ltd in 2009. Aidan Elliott Construction Ltd was a medium sized building contractor based in the Republic of Ireland. The company in question had an annual turnover of €15m, and was engaged in procuring construction contracts through competitive tendering. The contracts in question ranged in value between €200,000 and €12m. My responsibilities included pricing individual tenders, and compiling all the necessary documentation surrounding the procurement process for that company.As a company, we were pricing work on a competitive …

Developing A Collaborative Virtual Learning Environment Between Students In Cross Disciplines In The Built Environment., Fiacra Mcdonnell, Ruairi Hayden

Articles

Integrated Project Delivery is a rapidly developing approach to Design and Construction.This approach uses business structures, new technologies, and newly developing practices to collaboratively utilise the talents and contributions of all participants in the Design and Construction process.This project replicated this approach by creating a collaborative project between the School of Construction and the School of Real Estate and Construction Economics. The term “collaborative learning” refers to a method of delivery in which students at various performance levels work together in small groups towards a common goal. The students were responsible for one another’s learning as well as their own. …

Cereal Grain Combustion In Domestic Boilers, Andrew Keppel, John Finnan, Bernard Rice, Philip Owende, Kevin Macdonnell

Articles

This study compared the combustion characteristics and the combustion behaviour of oats, barley, triticale and wheat to that of wood pellets. Sustained grain combustion in domestic boilers was feasible but problematic, the main impediment being clinker formation with ash agglomeration. Clinker formation was lowest for oats which burned easily with fewer operational problems. Triticale displayed reasonably good combustion characteristics and also ignited easily. In contrast, barley and wheat proved difficult to ignite while barley combustion was prone to self-extinguish. Thermal and combustion efficiency and heat output were considerably higher at a grain moisture content of 15% compared to a moisture …

Environmental Consequences Of A Power Plant Shut-Down: A Three-Dimensional Water Quality Model Of Dublin Bay, Zeinab Bedri, Michael Bruen, Aodh Dowley, Barthelomew Masterson

Articles

A hydro-environmental model is used to investigate the effect of cessation of thermal discharges from a power plant on the bathing water quality of Dublin Bay. Before closing down, cooling water from the plant was mixed with sewage effluent prior to its discharge, creating a warmer, less-saline buoyant pollutant plume that adversely affects the water quality of Dublin Bay. The model, calibrated to data from the period prior to the power-plant shut-down (Scenario 1), assessed the water quality following its shut-down under two scenarios; (i) Scenario 2: continued abstraction of water to dilute sewage effluents before discharge, and (ii) Scenario …

Professional Skills Portfolio For A Progressive Engineering Education, Dermot Mcgarthy, David Kennedy

Articles

At the 2013 launch of the return to work scheme, “Springboard” in Dublin, it was stated that employers were seeking staff with enhanced language, presentation, communication, coping, and team-working skills. Graduates without these skills were finding it more difficult to gain permanent employment and were more likely to find themselves out of work unless they developed these skills. Enhancing personal development skills in education requires a revision of existing programmes. Not alone will these skills open new doors of opportunity for those who have lost their jobs during the recession, but should help sustain them going forward. The education of …

Estimating The Wind Resource In An Urban Area: A Case Study Of Micro Wind Generation Potential In Dublin, Ireland, Keith Sunderland, Gerald Mills, Michael Conlon

Articles

The micro-turbine wind market in cities faces significant challenges due to the complexities associated with the urban terrain but, if a renewable solution to increasing energy demand is to be achieved, energy conversion systems where populations are concentrated, that is cities, must be considered. This research evaluates the urban wind resource by employing a physically-based empirical model to link wind observations at a conventional meteorological site to those acquired at urban sites. The approach is based on urban climate research that has examined the effects of varying surface roughness on the wind-field between and above buildings. Here, this is applied …

Detecting Point-Like Sources Of Unknown Frequency Spectra, Raffaele Solimene, Giuseppe Ruvio, Angela Dell’Aversano, Antonio Cuccaro, Max Ammann, Rocco Pierri

Articles

The problem of detecting point-like sources whose frequency spectrum is unknown is addressed. Limitations of single-frequency approaches are identified by analytical as well as numerical arguments. To overcome these limits, different multifrequency approaches which combine frequency data incoherently are compared. In particular, a novel multifrequency MUSIC-like algorithm based on interferometric concepts is proposed. Results show that the algorithm outperforms other methods under comparison.

Thermal Performance Analysis Of A Solar Water Heating System With Heat Pipe Evacuated Tube Collector Using Data From A Field Trial, Lacour Ayompe, Aidan Duffy

Articles

This paper presents an analysis of the thermal performance of a solar water heating system with heat pipe evacuated tube collector using data obtained from a field trial installation over a year in Dublin, Ireland. An automated sub‐system was developed and incorporated to control the hot water draw‐offs and electric immersion heater to mimic the operation of solar water heating systems in domestic dwellings. The maximum recorded collector outlet fluid temperature was 70.3^oC while the water temperature at the bottom of the hot water tank was 59.5^oC. The annual average daily energy collected was 20.4 MJd …

Integrating Emotional Attachment And Sustainability In Electronic Product Design, Alex Lobos, Callie W. Babbitt

Articles

Current models for Information and Communication Technology (ICT) products encourage frequent product replacement with newer versions that offer only minor incremental improvements. This pattern, named planned obsolescence, diminishes user experience and shortens product lifespan. This paper presents the conceptual basis for a two-part integrated approach to combating planned obsolescence in ICT devices. First, design for emotional attachment, which creates products that users enjoy, value, and use for longer. Second, technological adaptability, which anticipates product upgrades and repairs as new technologies emerge. A model interdisciplinary design course in industrial design and sustainability, also described herein, trains students to apply this approach …

The Effects Of Physical Activity On Greenhouse Gas Emissions For Common Transport Modes In European Countries, Aidan Duffy, Robert Crawford

Articles

This paper applies a life cycle methodology to estimate activity-related contributions of transport modes to GHG emissions. The methodology uses national input-output tables, environmental accounts, household budget data and nutritional data to derive food-sector GHG coefficients of consumption for ten European countries. The food energy requirements for each mode of transport are estimated taking account of the modal activity level and energy requirements. Walking, cycling, driving and bus travel are considered. Typical national food energy-related emissions for walking, cycling, and driving ranged from 25.6 - 77.3 gCO2-eq/pass.km, 10.4 - 31.4 gCO2-eq/pass.km and 1.7 - 5.2 gCO2-eq/pass.km; passenger transport was found …

Advances In The Synthesis Of Zno Nanomaterials For Varistor Devices, Suresh Pillai, John M. Kelly, Raghavendra Ramesh, Declan Mccormack

Articles

ZnO based varistors are widely used for overvoltage protection in many electrical and electronic circuits, at voltages ranging from a few to over a million volts. By careful control of the microstructure, through nanostructuring by chemical routes, it should be possible to produce varistors with high breakdown voltage (Vc), as this is proportional to the number of active grain boundaries in the sintered body. This property is particularly important for the production of the small-sized varistors needed for modern electronic instruments such as tablet computers and mobile phones. The current review will outline the recent advances in the chemical processing …

Anti-Bacterial Activity Of Indoor Light Activated Photocatalysts, Suresh Pillai, Michael Seery, Damian Synnott, Stephen Hinder, Georg Michlits

Articles

Nanocrystalline photocatalysts, prepared under ambient conditions using a microwave assisted syn-thesis, show indoor light photocatalytic activity for the degradation of Staphylococcus aureus and Escherichia coli. The zinc sulphide (ZnS) nanomaterials, prepared by a microwave assisted synthesis, are shown to be cubic blende structure with an average crystallite size of 4–6 nm. The anti-bacterial activ-ity of these nanomaterials is investigated under irradiation from a 60 W light bulb and photocatalytic activity is revealed to be due to the defects present in the crystal structure. The ZnS shows anti-bacterial action as both a bacteriostatic and bacteriocidal (88% reduction in the amount of …

Evaluation Of Time Series Techniques To Characterise Domestic Electricity Demand, Fintan Mcloughlin, Aidan Duffy, Michael Conlon

Articles

This paper discusses time series approaches, often used by Transmission System Operators (TSOs) to forecast system demand, and applies them at an individual dwelling level. In particular, two techniques, Fourier transforms and Gaussian processes were evaluated and used to characterise individual household electricity demand. The performance of the characterisation approaches were evaluated based on Pearson correlation coefficient, descriptive statistics and paired sample t-tests for electrical parameters: Total Electricity Consumption, Maximum Demand, Load Factor and Time of Use of maximum electricity demand. Finally, a number of time series tests were carried out to ensure certain properties remained between the original and …

State Of The Irish Housing Stock - Modelling The Heat Losses Of Ireland’S Existing Detached Rural Housing Stock & Estimating The Benefit Of Thermal Retrofit Measures On This Stock, Ciara Ahern, Philip Griffiths, Micheal O'Flaherty

Articles

Ireland’s housing stock has been identified as being amongst the least energy efficient in Northern Europe. Consequently, atmospheric emissions are greater than necessary. Government funded schemes have been introduced to incentivise the uptake of thermal retrofit measures in the domestic Irish market. A study of Ireland’s housing highlights the dominance of detached houses (43%), 72% of which are rurally located and are predominantly heated with fuel oil. This paper investigates the economic and carbon case for thermal retrofit measures to the existing detached, oil centrally heated, rural housing stock. The study found the case for energy efficiency measures to be …