Engineering Commons^™

Nanostructured Apatite-Mullite Glass-Ceramics For Enhanced Primary Human Osteoblast Cell Response, Gordon Cooke, Conor Dunne, Sarah Keane, Daithi De Faoite, Seamas Donnelly, Kenneth Stanton

Articles

This work investigates the difference in viability of primary human foetal osteoblast cells on a glass-ceramic surface with nanoscale topography relative to viability on a smooth glass-ceramic surface containing a bioactive phase. Apatite-mullite glass-ceramics containing bioactive fluorapatite (Ca₁₀(PO₄)₆F₂) and bioinert mullite (Si₂Al₆O₁₃) were synthesised and subsequent heat-treatment was optimised to form nano-sized fluorapatite crystals. Etching was used to selectively remove the bioactive phase, producing a surface with disordered nanoscale topography. Cells were seeded onto a smooth polished glass-ceramic substrate with the bioactive phase intact, an etched …

Into The Deep: The Role Of Paradigms In Understanding Engineering Education For Sustainable Development, Iacovos Nicolaou, Eddie Conlon, Brian Bowe

Articles

This article presents summary findings of a mixed methods research project exploring the provision of education for sustainable development (SD) in seven Irish engineering degree programmes. Drawing on Sterling’s (2004) iceberg metaphor and Critical Realism it seeks to identify the underlying socio-cultural barriers preventing a holistic integration of SD in engineering education. It argues that the current focus is predominantly on the environmental dimension of SD and that there are a set of reinforcing mechanisms facilitating the provision of disciplinary education aimed at producing technically proficient, employable graduates in which the social dimension of SD is marginalised. This is underwritten …

Reliability-Based Designs Procedure Of Earth Retaining Walls In Geotechnical Engineering, Juan Camilo Viviescas, Juan Pablo Osorio, Julio E. Canon

Articles

The design and construction of foundations, retaining structures and slopes are usually based on deterministic formulations that do not allow the distinction between the natural variability and the inherent dispersion in the geotechnical parameters. Due to the inherent variability of the soil properties, there is a growing trend to implement reliability-based designs in geotechnical engineering to reduce design uncertainties by probabilistic methods. The reliability designs require the definition of the probability density functions of the geotechnical properties, as well as knowledge of the spatial variability of soils. This paper identifies the procedures, type of soil investigations, simulations and the most …

Modelling Tree Contribution In Susceptibility Analysis Of Shallow Llandslides, Roberto José Marín Sánchez, Juan Pablo Osorio

Articles

In this paper an assessment of shallow landslides susceptibility in a tropical and mountainous terrain is made. A method that allows to model slope stability over large areas is used. Tree contribution is quantified by means of three parameters: rainfall interception, root reinforcement and tree surcharge. A rainfall interception model is used to determine the rain available for infiltration and its temporal distribution during the simulation. The hydrological models included in TRIGRS are described, which allows to determine the pore water pressure depending on the initial conditions. This pore water pressure is used in the revised infinite slope stability model, …

Advances In Diamond Nanofabrication For Ultrasensitive Devices, Stefania Castelletto, Lorenzo Rosa, Jonathan Blackledge, Mohammed Zaher Al Abri, Albert Boretti

Articles

This paper reviews some of the major recent advances in single-crystal diamond nanofabrication and its impact in nano- and micromechanical, nanophotonics and optomechanical components. These constituents of integrated devices incorporating specific dopants in the material provide the capacity to enhance the sensitivity in detecting mass and forces as well as magnetic field down to quantum mechanical limits and will lead pioneering innovations in ultrasensitive sensing and precision measurements in the realm of the medical sciences, quantum sciences and related technologies.

K-Bit-Swap: A New Operator For Real-Coded Evolutionary Algorithms, Aram Ter-Sarkisov, Stephen Marsland

Articles

There has been a variety of crossover operators proposed for Real-Coded Genetic Algorithms (RCGAs), which recombine values from the same location in pairs of strings. In this article we present a recombination operator for RC- GAs that selects the locations randomly in both parents, and compare it to mainstream crossover operators in a set of experiments on a range of standard multidimensional optimization problems and a clustering problem. We present two variants of the operator, either selecting both bits uniformly at random in the strings, or sampling the second bit from a normal distribution centered at the selected location in …

Design And Planned Obsolescence. Theories And Approaches For Designing Enabling Technologies, Matteo Zallio, Damon Berry

Articles

We are currently living in a decade where smart objects and Internet of Things (IoT)-based devices are becoming part of daily life in different contexts. This research seeks to investigate and verify, by using a formal literature review methodology, the most visible aspects of technological development, within the Industry 4.0 and IoT scenario, in relation to the theories of the so called “Planned Obsolescence”.

This study covers a defined number of works on Design theories and practices on how to face the issue of built-in obsolescence of devices in the era of the Connected Devices. The majority of the works …

An Evaluation Of The Efficiency Of Compartmented Alginate Fibres Encapsulating Rejuvenator As Asphalt Pavement Healing System, Amir Tabakovic, Luke Schuyffel, Aleksandar Karac, Erik Schlangen

Articles

This paper explores the potential methods for evaluating a healing system for asphalt pavements. The healing system under investigation involves compartmented calcium-alginate fibres encapsulating an asphalt binder healing agent (rejuvenator). This system presents a novel method of incorporating rejuvenators into asphalt pavement mixtures. The compartmented fibres are used to distribute the rejuvenator throughout the pavement mixture, thereby overcoming some of the problems associated with alternate asphalt pavement healing methods, i.e., spherical capsules and hollow fibres. The asphalt healing efficiency methods to be evaluated in this paper include: (i) standard test methods for asphalt pavements, such as the Indirect Tensile Strength …

Magnetic Field Sensor Based On A Combination Of A Microfiber Coupler Covered With Magnetic Fluid And A Sagnac Loop, Fangfang Wei, Arun Mallik, Dejun Liu, Qiang Wu, Gang-Ding Peng, Gerald Farrell, Yuliya Semenova

Articles

This paper proposes a novel magnetic field sensor based on a microfiber coupler (MFC) combined with a magnetic fluid (MF) in a Sagnac loop formed from a polarization maintaining fiber (PMF). Thanks to the small (~2.6μm) waist diameter of the MFC, the resulting interference is strongly influenced by the presence of the MF and this leads to the desirable high sensitivity of the structure to the applied magnetic field. The maximum magnetic field sensitivities of −100pm/mT and −488pm/mT have been experimentally demonstrated with the PMF lengths of 75cm and 20cm respectively in the range of magnetic field strengths from 0 …

Broadband Acoustic Measurement Of The Agar-Based Tissue Mimicking Material – A Longitudinal Study, Adela Rabell-Montiel, Jacinta Browne, Stephen Pye, Tom Anderson, Carmel Moran

Articles

Commercially available ultrasound quality assurance test phantoms rely upon the long-term acoustic stability of tissue-mimicking-materials (TMMs). The measurement of the acoustic properties can be technically challenging and it is important to ensure its stability. The standard technique is to film-wrap samples of TMM and to measure the acoustic properties in a water bath. In this study, a modified technique is proposed whereby the samples of TMM are measured in a preserving fluid that is intended to maintain their characteristics. The acoustic properties were evaluated using a broadband pulse-echo substitution technique over the frequency range of 4.5 – 50 MHz at …

Ferric Chloride Assisted Plasma Pretreatment Of Lignocellulose, Rajeev Ravindran, Chaitanya Sarangapani, Swarna Jaiswal, Patrick Cullen, Amit Jaiswal

Articles

In this study, a novel pretreatment for spent coffee waste (SCW) has been proposed which combines two techniques viz. atmospheric air plasma and FeCl₃ to create a superior pretreatment that involves Fenton chemistry. The pretreatment was optimised employing Taguchi Design of Experiments, and five parameters were taken into consideration viz. biomass loading, FeCl₃ concentration, H₂SO₄ concentration, plasma discharge voltage and treatment time. The composition analysis of the pretreated SCW revealed substantial amounts of lignin removal, with a maximum for process conditions of 70kV for 2min in an acidic environment containing 1% H₂SO_{4 …}

A Comparative Analysis Of Pretreatment Strategies On The Properties And Hydrolysis Of Brewers’ Spent Grain, Rajeev Ravindran, Swarna Jaiswal, Nissreen Abu-Ghannam, Amit Jaiswal

Articles

In this study, brewer’s spent grain (BSG) was subjected to a range pretreatments to study the effect on reducing sugar yield. Glucose and xylose were found to be the predominant sugars in BSG. Brewers spent grain was high in cellulose (19.21g/100g of BSG) and lignin content (30.84g/100g of BSG). Microwave assisted alkali (MAA) pretreatment was found to be the most effective pretreatment for BSG, where the pretreatment was conducted at 400W for 60s. A maximum reducing yield was observed with high biomass loading (1g/10ml), cellulase (158.76 μl/10ml), hemicellulase (153.3 μl/10ml), pH (5.4) and an incubation time (120h). Upon enzymatic hydrolysis, …

Effects Of Vegetation On Slope Stability: A Review, Roberto José Marín Sánchez, Juan Pablo Osorio

Articles

Slope stability is usually affected by factors that reduce soil strength and increase driving forces acting on the slope material, sometimes generating mass movements. Among these factors, vegetation has an important role related to hydrological (e.g. evapotranspiration and infiltration) and mechanical (e.g. tree surcharge and root reinforcement provided by trees) mechanisms. In this review, vegetation influences associated to slope stability are identified, describing the mechanisms involved in the occurrence of mass movements. Finally, the way these factors affect slope stability is explained according to soil properties, climatic conditions and environmental characteristics.

Two-Step Sequential Pretreatment For The Enhanced Enzymatic Hydrolysis Of Coffee Spent Waste, Rajeev Ravindran, Swarna Jaiswal, Nissreen Abu-Ghannam, Amit Jaiswal

Articles

In the present study, eight different pretreatments of varying nature (physical, chemical and physico-chemical) followed by a sequential, combinatorial pretreatment strategy was applied to spent coffee waste to attain maximum sugar yield. Pretreated samples were analysed for total reducing sugar, individual sugars and generation of inhibitory compounds such as furfural and hydroxymethyl furfural (HMF) which can hinder microbial growth and enzyme activity. Native spent coffee waste was high in hemicellulose content. Galactose was found to be the predominant sugar in spent coffee waste. Results showed that sequential pretreatment yielded 350.12mg of reducing sugar/g of substrate, which was 1.7-fold higher than …

Irish Bim Study 2017, Barry Mcauley, Alan Hore, Roger West

Articles

The Construction IT Alliance (CitA) recently published its Global BIM Study as part of its BIM Innovation Capability Programme (BICP). The study sought to identify how BIM was being currently addressed in 27 countries across the globe. The study sought to identify the presence of three key ingredients in these countries:

1. Regulatory requirement for BIM

2. Champions driving BIM

3. Noteworthy publications

The report identified a number of recurring themes that would help to shape Ireland’s BIM programme. The report concluded that Ireland should adopt a programme of partnership between industry and the Irish Government in order to affect …

Effect Of Sky Conditions On Light Transmission Through A Suspended Particle Device Switchable Glazing, Aritra Ghosh, Brian Norton, Aidan Duffy

Articles

A suspended particle device (SPD) switchable glazing changes its state from opaque to transparent in the presence of a power supply. SPD glazing's near normal transmission varies with incident angle and clearness index. Due to a lower diffuse component, higher glazing transmission ensues at higher clearness indices. Transmittance values for different azimuthal incident angle for a SPD glazing for its “transparent” and “opaque” states have been determined. In Dublin, below 0.5 clearness index, isotropic diffuse transmittance was prevailed while transmission of direct insolation was dominant above 0.5 clearness index. For south facing vertical plane SPD glazing transmittance in its transparent …

Stakeholder Outcomes In A Wind Turbine Investment; Is The Irish Energy Policy Effective In Reducing Ghg Emissions By Promoting Small-Scale Embedded Turbines In Sme's?, Tony Kealy

Articles

As a member state of the European Union (EU), Ireland has adopted an energy policy which includes promoting wind powered electricity generators as an economically viable, GHG-reducing, alternative to environmentally damaging fossil-fuel driven electrical generators. This longitudinal, inductive in-depth study investigates the outcomes for the government and other stakeholders involved in a wind turbine project investment by a Small-to-Medium-Enterprise (SME) based in rural Ireland. A case study research methodology is used to acquire and analyse quantitative numerical data from multiple sources including electrical power and energy meters, historical electricity bills and company sustainability reports. The study found that the installation …

Determination Of Reliable Fatigue Life Predictors For Magnetorheological Elastomers Under Dynamic Equi-Biaxial Loading, Yangen Zhou, Liang Jiang, Shaojuan Chen, Jianwei Ma, Tony Betts, Stephen Jerrams

Articles

Fatigue life prediction is of great significance in ensuring magnetorheological elastomer (MRE) based rubber components exhibit reliability and do not compromise safety under complex loading and this necessitates the development of plausible fatigue life predictors for MREs. In this research, silicone rubber based MREs were fabricated by incorporating soft carbonyl iron magnetic particles. Equi-biaxial fatigue behaviour of the fabricated MREs was investigated by using the bubble inflation method. The relationship between fatigue life and maximum engineering stress, maximum strain and strain energy density were studied. The results showed that maximum engineering stress and stored energy density can be used as …

Characterization Of The Sub-Micrometer Hierarchy Levels In The Twist-Bend Nematic Phase With Nanometric Helices Via Photopolymerization: Explanation For The Sign Reversal In The Polar Response, Vitaly Panov, Sithara Sreenilayam, Yuri Panarin, Jagdish Vij, Chris Welch, Georg Mehl

Articles

Photopolymerization of a reactive mesogen mixed with a mesogenic dimer, shown to exhibit the twist-bend nematic phase (NTB), reveals the complex structure of the self-deformation patterns observed in planar cells. The polymerized reactive mesogen retains the structure formed by liquid crystalline molecules in the twist bend phase, thus enabling its observation by scanning electron microscopy (SEM). Hierarchical ordering scales ranging from tens of nanometers to micrometers are imaged in detail. Submicron features, anticipated from earlier X-ray experiments, are visualized directly. In the self-deformation stripes formed in the NTB phase, the average director field is found tilted in …

Hybrid Graphene–Copper Uwb Array Sensor For Brain Tumor Detection Via Scattering Parameters In Microwave Detection System, Mohd Aminudin Jamlos, Abdul Hafiizh Ismail, Mohd Faizal Jamlos, Adam Narbudowicz

Articles

Hybrid graphene–copper ultra-wideband array sensor applied to microwave imaging technique is successfully used in detecting and visualizing tumor inside human brain. The sensor made of graphene coated film for the patch while copper for both the transmission line and parasitic element. The hybrid sensor performance is better than fully copper sensor. Hybrid sensor recorded wider bandwidth of 2.0–10.1 GHz compared with fully copper sensor operated from 2.5 to 10.1 GHz. Higher gain of 3.8–8.5 dB is presented by hybrid sensor, while fully copper sensor stated lower gain ranging from 2.6 to 6.7 dB. Both sensors recorded excellent total efficiency averaged …

Development Of Ferroelectricity In The Smectic Phases Of 4-Cyanoresorcinol Derived Achiral Bent-Core Liquid Crystals With Long Terminal Alkyl Chains, Sithara Pavithran Sreenilayam, J. K. Vij, Yuri Panarin, Anne Lehman

Articles

Bent-core molecules can form numerous polar and symmetry broken liquid crystalline phases with fascinating properties. Here we report the characteristics of a previously unknown polar synclinic smectic phase, Sm C S P X , found in the phase sequence of an achiral bent-core material with a 4-cyanoresorcinol bisbenzoate core, terminated by long linear alkyl chains ( n = 18 ) on both ends. This phase exists over a narrow range of temperatures and is sandwiched in between the random polar synclinic smectic phase ( Sm C S P R ) and polar synclinic ferroelectric ( Sm C S P F …

Magnetic Field Sensor Based On A Combination Of A Microfiber Coupler Covered With Magnetic Fluid And A Sagnac Loop, Fangfang Wei, Arun Mallik, Dejun Liu, Qiang Wu, Gang-Ding Peng, Gerald Farrell, Yuliya Semenova

Articles

This paper proposes a novel magnetic field sensor based on a microfiber coupler (MFC) combined with a magnetic fluid (MF) in a Sagnac loop formed from a polarization maintaining fiber (PMF). Thanks to the small (~2.6 μm) waist diameter of the MFC, the resulting interference is strongly influenced by the presence of the MF and this leads to the desirable high sensitivity of the structure to the applied magnetic field. The maximum magnetic field sensitivities of −100 pm/mT and −488 pm/mT have been experimentally demonstrated with the PMF lengths of 75 cm and 20 cm respectively in the range of …

Multi-Band Antenna Array Based On Double Negative Metamaterial For Multi Automotive Applications, Mohd Jamlos, Abdulrahman Alqadami,, Imtiaz Islam, Ping Soh, Rizalman Mamat, Khairil Khairi, Adam Narbudowicz

Articles

Nowadays, the demand for antennas in wireless communication system for automotive applications is rising at a rapid rate [1, 2]. Their usage includes collision avoidance system (CAS), Vehicle-to-vehicle communications, pre-crash safety systems, Global Positioning Systems (GPS), tyre pressure monitoring system (TPMS), Wireless Local Area Network (WLAN), etc. To enhance its effectiveness in these new applications, a small, multi-band, multi-functional antenna is required instead of conventional single band antennas [2, 3]. Such multifunctional antennas with favourable radiation characteristics are more practical in addressing modern antenna design requirements. However, the achievement of the above mentioned antenna’s features using conventional materials and structures …

Application Of Phase Shifting Electronic Speckle Pattern Interferometry In Studies Of Photoinduced Shrinkage Of Photopolymer Layers, Mohesh Moothanchery, Viswanath Bavigadda, Manojit Pramanik, Vincent Toal, Izabela Naydenova

Articles

Photoinduced shrinkage occurring in photopolymer layers during holographic recording was determined by Phase Shifting Electronic Speckle Pattern Interferometry. Phase maps were calculated from the changes in intensity at each pixel due to the phase differences introduced between object and reference beams. Shrinkage was then obtained from the changes in phase as recording proceeded. The technique allows for whole field measurement of the dimensional changes in photopolymers during holographic recording.

Strengthening The Development Of The Short-Rotation Plantations Bioenergy Sector: Policy Insights From Six European Countries, Carlos Parra-Lopez, Martin Holley, Kevin Lindegaard, Samir Sayadi, Gonzalo Esteban-Lopez, Victor Duran-Zuazo, Christoph Knauer, Hans-Georg Von Engelbrechten, Ralf Winterber, Annika Henriksson, Annette Lamley, Anders Nylander, Susanne Paulrud, Pauline Leonard, Patrick Daly, Lukasz Drzewaszewski, Wojciech Rzewuski

Articles

This paper, based on a participatory methodological framework involving expert stakeholders and researchers from six European countries (Germany, Ireland, Poland, Spain, Sweden and UK), analyses the priority issues for the development of short-rotation plantations (SRP), and proposes a series of policy strategies to strengthen this development. The results indicate that there is a lack of awareness of the multifaceted benefits of SRP at the level of farmers, policy makers and public authorities. More research is required to put a value on the multifunctionality of SRP and justify its public support. Small-scale projects using established technologies are also required with energy …

Reneb - Running The European Network Of Biological Dosimetry And Physical Retrospective Dosimetry, Ulrike Kulka, Michael Abend, Liz Ainsbury, Christophe Badie, Joan-Francesc Barquinero, Leonardo Barrios, Christina Beinke, Emanuela Bortolin, Alexandra Cucu, Fiona Lyng

Articles

Purpose: A European network was initiated in 2012 by 23 partners from 16 European countries with the aim to significantly increase individualized dose reconstruction in case of large-scale radiological emergency scenarios.

A Packaged Whispering Gallery Mode Strain Sensor Based On A Polymer Wire Cylindrical Micro Resonator, Vishnu Kavungal, Gerald Farrell, Qiang Wu, Arun Mallik, Yuliya Semenova

Articles

We propose a whispering gallery mode (WGM) strain sensor formed by a polymer-wire cylindrical micro resonator for strain measurement applications. WGMs are generated by evanescently coupling light into the polymer-wire resonator from a silica fiber taper fabricated by the micro heater brushing technique. Accurate and repeatable measurements of a strains up to one free spectral range (FSR) shift of the WGMs (corresponding to 0.33 % of the polymer-wire elongation, 3250 μɛ) are demonstrated experimentally with the proposed sensor. Practical packaging method for the proposed strain sensor on a glass microscope slide has also been realized making the sensor portable and …

Precision Control Of Flow Rate In Microfluidic Channels Using Photoresponsive Soft Polymer Actuators, Colm Delaney, Peter Mccluskey, Simon Coleman, Jeffrey Whyte, Nigel Kent, Dermot Diamond

Articles

A novel approach that allows control of flow in microfluidic channels with unsurpassed performance using light is described. Valve structures have been created using photoresponsive hydrogels based on spiropyran-functionalised pNIPAAm hydrogels photopolymerised around pillar structures within the channels. Valve actuation is controlled from outside the fluidic system using externally located LEDs. Highly precise and accurate flow rates can be selected by passing real-time flow rate measurements into a PID algorithm. The optimised algorithm also minimises overshoot of the selected flow rate, eliminates flow rate drift, and improves the system response time. In addition to the dramatic improvements in flow rate …

Adaptive Linear Prediction For Optimal Control Of Wind Turbines, Mahinsasa Narayana, Keith Sunderland, Ghanim Putrus, Michael Conlon

Articles

In order to obtain maximum power output of a Wind Energy Conversion System (WECS), the rotor speed needs to be optimised for a particular wind speed. However, due to inherent inertia, the rotor of a WECS cannot react instantaneously according to wind speed variations. As a consequence, the performance of the system and consequently the wind energy conversion capability of the rotor are negatively affected. This study considers the use of a time series Adaptive Linear Prediction (ALP) technique as a means to improve the performance and conversion efficiency of wind turbines. The ALP technique is introduced as a real …

Compact Facility For Testing Steady And Transient Thermal Performance Of Building Walls, Aimee Byrne, Gerard Byrne, Anthony Robinson

Articles

Energy efficiency retrofit of buildings represents a key effort in reducing EU energy demand by 20% by 2020. However, predictions tend to overestimate savings by large percentages. The shortfall in savings can be attributed to incorrect predictive techniques, comfort takeback along with other behavioural and workmanship variables. Common predictive techniques related to heat loss tend to be based on the U-value of the building envelope. This paper presents the design of a more straightforward and compact version of the traditional Hot-Box apparatus (measures U-value) which instead determines the thermal resistance of samples of building envelope. U-value includes the need to …