Engineering Commons^™

Multi-Objective Layout Optimization Of A Generic Hybrid-Cooled Data Centre Blade Server, Assel Sakanova, Sajad Alimohammadi, Jaakko Mcevody, Sara Battaglioli, Tim Persoons

Articles

The rapid global increase in energy consumption by data centres requires new improved cooling solutions and techniques to be developed and implemented. In a typical data centre, approximately a third of the total power consumption is needed for the cooling infrastructure, resulting in high power usage effectiveness (PUE) values. The main culprits of raised PUE are legacy air-cooled data centres, exhausting only low grade waste heat for which capture and re-use is challenging. This study investigates numerically the potential for energy recuperation by a server-level internal layout optimization for a hybrid air/liquid-cooled server. The approach combines multi-objective genetic algorithm (MOGA) …

Ka-Band Planar Vivaldi Antenna With A Core For High-Gain, Manh Ha Hoang, Kansheng Yang, Matthias John, Patrick Mcevoy, Max Ammann

Articles

A planar Vivaldi antenna structure with a core element is proposed for high gain. Techniques to achieve a significant gain improvement over the full Ka (24-40 GHz) band are implemented; including a frequency-independent excitation method, the introduction of logarithmic ripple on the lateral edges and enclosing the antenna in a dielectric material.

Preliminary Findings Of A Phenomenographic Research Study Into Academic Conceptions Of The Term Professional Skills, Una Beagon, Brian Bowe

Other resources

This presentation outlines preliminary findings of a phenomenographic study of academic conceptions of the term professional skills.

Temperature-Compensated Magnetic Field Sensing With A Dual-Ring Structure Consisting Of Microfiber Coupler-Sagnac Loop And Fiber Bragg Grating - Assisted Resonant Cavity, Fangfang Wei, Dejun Liu, Arun Kumar Mallik, Gerald Farrell, Qiang Wu, Gang-Ding Peng, Yuliya Semenova

Articles

A novel temperature-compensated magnetic field sensor based on a ring erbium-doped fiber laser combined with a fiber Bragg grating (FBG) and a Sagnac loop containing a microfiber coupler (MFC) and magnetic fluid is proposed and investigated. Thanks to the dual-ring structure of the MFC-Sagnac loop and the FBG-assisted resonant cavity, the output of the structure has two distinct laser peaks. In addition to the magnetic field sensing capability, the proposed structure can simultaneously provide temperature information. The maximum experimentally demonstrated sensitivity to a magnetic field determined from the spectral shift of one laser peak is 102 pm/mT in the magnetic …

Microwave Self-Healing Technology As Airfield Porous Asphalt Friction Course Repair And Maintenance System, Amir Tabakovic, Declan O'Prey, Drew Mckenna, David Woodward

Research and Innovation - Articles

A problem increasingly faced by airport authorities is the maintenance of runways. Due to their large aircraft loadings associated with take-off and landing operations, runways experience surface deterioration. Poor quality runway surfaces cannot be tolerated in such an environment. Maintenance issues must be carried out to maximise safety and minimise the risk of aircraft damage. A recent development has been the introduction of self-healing technologies such as rejuvenator encapsulation, induction and microwave heating to address these issues. This paper summarises a laboratory investigation to determine the effectiveness of microwave self-healing for crack repair of Porous Friction Course (PFC) used for …

Air Quality Modelling For Ireland, Aoife Donnelly, Bruce Misstear, Brian Broderick

Reports

Air pollution is the primary environmental cause of premature death in the EU (European Commission, 2013) and the most problematic pollutants across Europe have consistently been oxides of nitrogen (e.g. nitrogen dioxide (NO₂)), particulate matter (e.g. PM₁₀, PM_2.5) and ozone (O₃). While measurements form an important aspect of air quality assessment, on their own they are unlikely to be sufficient to provide an accurate spatial and temporal description of the pollutant concentrations for exposure assessment and moreover they cannot provide information regarding future air quality. Annex XVI of 2008/50/EC requires member states …

Standardisation In Construction Cost Control (A Method Of Approach), Charles Mitchell

Other Resources

As construction projects became larger and more complex the need to control their costs became greater. As a result, cost control professions such as the cost manager and the quantity surveyor emerged. Cost control mechanisms have evolved with changes in the construction sectors. It is now apparent that the output of the construction sector plays an important part in the economic stability and growth of both national and international economies. Recently a coalition was formed to produce an international construction measurement standard (ICMS). All member organisations of the ICMS have pledged to mandate the standard amongst their membership and seek …

Standardisation In Construction Cost Control, Charles Mitchell

Other Resources

Poster presentation submitted as to the School of Surveying and Construction Management Research and Innovation Industry Evening, March 2019.

Bs News March/April

Building Services Engineering

No abstract provided.

The Influence Of Asphalt Ageing On Induction Healing Effect On Porous Asphalt Concrete, Shi Xu, Xueyan Liu, Amir Tabakovic, Erik Schlangen

Articles

Induction healing is a proven technology which is able to improve the self‐healing capacity of asphalt concrete. Healing is achieved via electromagnetic current produced by passing induction machine, where steel asphalt constituents heat up which in turn soften the bitumen in the asphalt layer, allowing it to flow and close cracks, repairing the damage. This paper reports on the study which investigated the influence of ageing on the healing capacity of Porous Asphalt (PA) concrete. Porous Asphalt concrete mix was prepared first, then subjected to an accelerated (laboratory) ageing process using a ventilated oven. In order to further evaluate the …

Visualising The Complex Features Of Source Code, Ivan Bacher

Doctoral

Software development is a complex undertaking composed of several activities that include reading, writing, and modifying source code. Indeed, previous studies have shown that the majority of the effort invested in software development is dedicated to understanding code. This includes understanding the static structure, dynamic behaviour, and evolution of the code. Given these particular characteristics, as well as the high complexity of source code, it is reasonable to consider how visualisation can facilitate source code understanding. This work proposes to extend existing software development tools with visualisations that can be used to encode the various complex features within a source …

Discussion: Effect Of Bentonite Slurry Pressure On Interface Friction Of Pipe Jacking, Ciaran Reilly, Trevor Orr

Articles

Pipe jacking is a technique used to construct tunnels by pushing prefabricated pipes through the ground from an entrance shaft to an exit shaft. This technique is referred as microtunneling in U.S. terminology, therefore, in the rest of the text, pipejacking and microtunneling will be used as having the same meaning. Pipe jacking is a more economical alternative to segmental lined tunnels. However, the main limitation of pipe jacking is the jacking distance, which is directly dependent on the friction between the pipe and the soil. Therefore, reducing the friction between the pipe and soil is a critical issue in …

Introducing The Default Effect: Reducing The Gap Between Theoretical Prediction And Actual Energy Consumed By Dwellings Through Characterising Data More Representative Of National Dwellings Stocks, Ciara Ahern

Doctoral

Dwelling stock models that include the renovation status of the dwelling stock enable energy analyses of the stock. Using Ireland’s predominant single‐family housing typology as a case study dwelling, the overarching objective of this research is to define a transparent generalisable methodology to create a stock model from a large empirical Energy Performance Certification (EPC) database, employing reference dwellings (RDs) defined using a ‘bottom‐up’ approach. RDs are to be reported in compliance with Regulation No. (EU) 244/2012. The generalisable methodology defined allows for the development of stock models from EPC datasets. Where obtaining the required data would be prohibitively costly, …

Level Of Service And The Transit Neighbourhood: Observations From Dublin City And Surburbs, David O'Connor, Brian Caulfield

Articles

Few studies have looked at the impact Level-of-Service (LOS) might have on the distances people walk to public transport. The relationship, if any, has implications for transit-oriented-development and the viability of different transit modes serving suburban areas. This paper examines pedestrian catchment areas and LOS across a light rail, a metro rail and two bus corridors in Dublin. Public transport users have been surveyed at 17 stops around the city and their trip origin identified. Catchment areas for bus services with high levels of service were found to be comparable and often greater than those for LRT or metro …

Optimization Of The Calcium Alginate Capsules For Self-Healing Asphalt, Shi Xu, Amir Tabakovic, Xueyan Liu, Damian Palin, Erik Schlangen

Research and Innovation - Articles

Featured Application: This self-healing technology for asphalt pavements has the potential to greatly disrupt asphalt production methods (which have been stable over the past 100 years).This paper presents a development process of ‘calcium-alginate microcapsules encapsulating an asphalt bitumen rejuvenator’. The encapsulated rejuvenator is released when required (on demand) which rejuvenates the aged binder. Once crack is initiated and starts propagating it encounters a microcapsule, energy at tip of the crack opens the microcapsule, releasing the rejuvenator (healing agent). The rejuvenator will infuse into the aged binder soften it, allowing to flow, two broken edges to get into a contact and …

A Framework For Evaluating Model-Driven Self-Adaptive Software Systems, Basel Magableh

Articles

In the last few years, Model Driven Development (MDD), Component-based Software Development (CBSD), and context-oriented software have become interesting alternatives for the design and construction of self-adaptive software systems. In general, the ultimate goal of these technologies is to be able to reduce development costs and effort, while improving the modularity, flexibility, adaptability, and reliability of software systems. An analysis of these technologies shows them all to include the principle of the separation of concerns, and their further integration is a key factor to obtaining high-quality and self-adaptable software systems. Each technology identifies different concerns and deals with them separately …

A Deep Recurrent Q Network Towards Self-Adapting Distributed Microservices Architecture (In Press), Basel Magableh

Articles

One desired aspect of microservices architecture is the ability to self-adapt its own architecture and behaviour in response to changes in the operational environment. To achieve the desired high levels of self-adaptability, this research implements the distributed microservices architectures model, as informed by the MAPE-K model. The proposed architecture employs a multi adaptation agents supported by a centralised controller, that can observe the environment and execute a suitable adaptation action. The adaptation planning is managed by a deep recurrent Q-network (DRQN). It is argued that such integration between DRQN and MDP agents in a MAPE-K model offers distributed microservice architecture …

Context Oriented Software Middleware, Basel Magableh

Articles

This article proposes a new paradigm for building an adaptive middleware that supports software systems with self-adaptability and dependability. In this article, we wish to explore how far we can support the engineering of self- adaptive applications using a generic and platform-independent middleware architecture provided by non-specialised programming languages such as Context-Oriented Programming (COP), and Aspect-Oriented Programming (AOP), and not limited to a specific platform or framework. This gives the software developers the flexibility to construct a self-adaptive application using a generic and reusable middleware components that employ popular design patterns, instead of forcing the software developers to use a …

Deep Q Learning For Self Adaptive Distributed Microservices Architecture (In Press), Basel Magableh

Articles

One desired aspect of a self-adapting microservices architecture is the ability to continuously monitor the operational environment, detect and observe anomalous behavior, and provide a reasonable policy for self-scaling, self-healing, and self-tuning the computational resources in order to dynamically respond to a sudden change in its operational environment. The behaviour of a microservices architecture is continuously changing overtime, which makes it a challenging task to use a statistical model to identify both the normal and abnormal behaviour of the services running. The performance of the microservices cluster could fluctuate around the demand to accommodate scalability, orchestration and load balancing demands. …

The Effect Of Impact Location On Brain Strain, Stephen Tiernan, Gary Byrne Mr

Articles

Objective: To determine the effect of impact direction on strains within the brain.

Research design: Laboratory drop tests of hybrid III head-form and finite element simulation of impacts.

Methods and procedures: A head-form instrumented with accelerometers and gyroscopes was dropped from 10 different heights in four orientations: front, rear, left and right hand side. Twelve impacts with constant impact energy were chosen to simulate, to determine the effect of impact location. A finite element head model was used to simulate these impacts, using 6 degrees of freedom. Following this a further set of simulations were performed, where the same acceleration …

Cross-Correlation Template Matching For Liver Localisation In Computed Tomography, Patrick Leyden, Martin O'Connell, Derek Greene, Kathleen Curran

Session 5: Medical and Biomedical Imaging

Many of the current approaches to automatic organ localisation in medical imaging require a large amount of labelled patient data to train systems to accurately identify specific anatomical features. Cross- Correlation, also known as template matching, is a statistical method of assessing the similarity between a template image and a target image. This method has been modified and presented here to localize the liver in Computed Tomography volume images in the Coronal and Sagital planes to achieve a mean positioning error of approximately 11 mm and 20 mm respectively based on between 1 and 25 datasets to create the template …

A New Era For Reuse Social Enterprises In Ireland? The Capacities Required For Achieving Sustainability, Gerard Doyle

Articles

The conventional linear relationship between production and consumption is no longer sustainable. A key component of the transition towards a more sustainable society is the continuation in use of products for longer and the development of a repair and reuse culture. Reuse social enterprises contribute to addressing a range of environmental, economic and social issues facing urban areas. This paper is concerned with, firstly, the motivations for citizens to establish reuse social enterprises in Ireland. Secondly, the paper examines the factors that contribute to reuse social enterprises in Ireland becoming sustainable.

The research points to the necessity of reuse social …

Distribution Of Tm 3+ And Ni 2+ In Chalcogenide Glass Ceramics Containing Ga2s3 Nanocrystals: Influence On Photoluminescence Properties, Xiaosong Lu, Zhiqiang Lai, Jing Ren, Lukas Strizik, Tomas Wagner, Yanqiu Du, Gerald Farrell, Pengfei Wang

Articles

The distribution of Tm3+ and Ni2+ ions is unambiguously exhibited in 80GeS2-20Ga2S3 chalcogenide glass ceramics (GCs) containing Ga2S3 nanocrystals (NCs) by using advanced analytical transmission electron microscopy. Distinctively different distribution patterns of Tm3+ and Ni2+ ions are observed in the GCs obtained by controlled crystallization. The distribution of the dopants imposes strong influence on their optical properties which are revealed by absorption and photoluminescence (PL) spectra. Detailed discussions are given of the mechanisms of the crystallization-induced PL enhancement and quenching of the Tm3+ mid-infrared and Ni2+ near-infrared emissions, respectively.

Improving Unsupervised Learning With Exemplar Cnns, Eric Arazo, Noel E. O'Connor, Kevin Mcguinness

Session 3: Deep Learning for Computer Vision

Most recent unsupervised learning methods explore alternative objectives, often referred to as self-supervised tasks, to train convolutional neural networks without the supervision of human annotated labels. This paper explores the generation of surrogate classes as a self-supervised alternative to learn discriminative features, and proposes a clustering algorithm to overcome one of the main limitations of this kind of approach. Our clustering technique improves the initial implementation and achieves 76.4% accuracy in the STL-10 test set, surpassing the current state-ofthe- art for the STL-10 unsupervised benchmark. We also explore several issues with the unlabeled set from STL-10 that should be considered …

Eulerian Video Magnification Adaptation For Live Cell Microscopy Analysis, Paul Leamy, Jane Courtney

Session 5: Medical and Biomedical Imaging

In this paper an adaptation of the Eulerian Video Magnification technique is described for use with .TIFF files produced by a photo-conversion time lapse protocol for live cell microscopy, specifically for research into Acquired Immune Deficiency Syndrome. The tracking and characterisation of a protein found in Human Immunodeficiency Virus, to determine its dynamics and pathways is a key determinant in understanding the protein’s function. The aim of this algorithm is to process an image sequence in the temporal direction with the result being that changes in fluorescence for particular pixel locations, or regions of interest, are tracked and filtered thereby …

Visualizing And Interpreting Feature Reuse Of Pretrained Cnns For Histopathology, Mara Graziani, Vincent Andrearczyk, Henning Muller

Session 6: Applications, Architecture and Systems Integration

Reusing the parameters of networks pretrained on large scale datasets of natural images, such as ImageNet, is a common technique in the medical imaging domain. The large variability of objects and classes is, however, drastically reduced in most medical applications where images are dominated by repetitive patterns with, at times, subtle differences between the classes. This paper takes the example of finetuning a pretrained convolutional network on a histopathology task. Because of the reduced visual variability in this application domain, the network mostly learns to detect textures and simple patterns. As a result, the complex structures that maximize the channel …

Object Position Labelling In Video Using Prbs Audio Multilateration, Padraic Mcevoy, Paul Leamy, Damon Berry, David Dorran, Ted Burke

Session 4: 2D, 3D Scene Analysis and Visualisation

Supervised machine learning approaches for tracking objects’ positions in video typically require a large set of images in which the positions are labelled. Human labelling is time-consuming and automatic position labelling using visual markers is generally not possible because visible markers would corrupt the data. Here, we present an approach in which an object is tracked using a hidden tag that emits a PRBS audio signal. Four microphones arranged in a planar cross formation capture parallel recordings of the PRBS signal. Multilateration, using the time difference of arrival (TDoA) of the PRBS at each microphone, is used to estimate the …

An Investigation Into The Predictive Capability Of Customer Spending In Modelling Mortgage Default, Donal Finn [Thesis]

Dissertations

The mortgage arrears crisis in Ireland was and is among the most severe experienced on record and although there has been a decreasing trend in the number of mortgages in default in the past four years, it still continues to cause distress to borrowers and vulnerabilities to lenders. There are indications that one of the main factors associated with mortgage default is loan affordability, of which the level of disposable income is a driver. Additionally, guidelines set out by the European Central Bank instructed financial institutions to adopt measures to further reduce and prevent loans defaulting, including the implementation and …

A Novel Approach Towards Investigating The Performance Of Different Pvt Configurations Integrated On Test Cells: An Experimental Study, Vivek Tomar, Brian Norton, G. N. Tiwari

Articles

This study elaborates the theoretical and experimental analysis for the effectiveness of different photovoltaic thermal (PVT) configurations along with their building implications. An experiment was performed on especially designed four identical prototype test cells emphasise the building integration photovoltaic thermal (BiPVT) systems. A comparative analysis of four different possible PVT configurations integrated on identical test cells namely; Case 1: Glass-to-glass PV with duct integrated on a test cell, Case 2: Glass-to -glass PV without duct integrated on a test cell, Case 3: Glass to tedlar PV with duct integrated on a test cell and Case 4: Glass to tedlar PV …

Fused Silica Capillary Interferometer With A Layer-By-Layer Functional Coating For The Analysis Of Chemicals Content In Aqueous Solutions, Arun Kumar Mallik, Gerald Farrell, Qiang Wu, Yuliya Semenova

Articles

A simple fused silica capillary interferometric (FSCI) sensor has been proposed and investigated for the detection and analysis of multiple chemical compounds content in aqueous solutions. The sensor was fabricated by splicing a commercially available fused silica capillary (FSC) with two single mode fibers to create a 0.7 cm long air cavity. The fiber surface was functionalized with two different polymers: poly (allylamine hydrochloride) (PAH) and sol-gel silica in sequence using a layer-by-layer deposition method. The operating principle of the sensor relies on light interference in the fused silica capillary cavity due to adhesion of the different chemical compounds on …