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Full-Text Articles in Engineering

Properties Of Non-Tilted Bent-Core Orthogonal Smectic Liquid Crystal, S. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, A. Lehmann, C. Tschierske Jan 2012

Properties Of Non-Tilted Bent-Core Orthogonal Smectic Liquid Crystal, S. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, A. Lehmann, C. Tschierske

Articles

We present the properties of different achiral orthogonal polar smectic phases observed in a homologous series of bent-core molecular compounds. The macroscopically uniaxial SmAPR phase transforms to biaxial state by the application of higher electric fields and biaxial SmAPA phase undergoes biaxial-uniaxial-biaxial texture transformation with increasing electric fields,i.e.,initial antiferroelectric structure transforms into ferroelectric state under higher electric fields and it shows three different optically distinguishable states. The SmAPAR phase shows an entirely different response compared to other polar smectic phases under study. The dielectric measurements in the SmAPAR phase is the evidence of antiferroelectric behavior of uniaxial state. The polarizing …


Shifted Nmf With Group Sparsity For Clustering Nmf Basis Functions, Rajesh Jaiswal, Derry Fitzgerald, Eugene Coyle, Scott Rickard Jan 2012

Shifted Nmf With Group Sparsity For Clustering Nmf Basis Functions, Rajesh Jaiswal, Derry Fitzgerald, Eugene Coyle, Scott Rickard

Conference papers

Recently, Non-negative Matrix Factorisation (NMF) has found application in separation of individual sound sources. NMF decomposes the spectrogram of an audio mixture into an additive parts based representation where the parts typically correspond to individual notes or chords. However, there is a need to cluster the NMF basis functions to their sources. Although, many attempts have been made to improve the clustering of the basis functions to sources, much research is still required in this area. Recently, Shifted Non-negative Matrix Factorisation (SNMF) was used to cluster these basis functions. To this end, we propose that the incorporation of group sparsity …


Vocal Separation Using Nearest Neighbours And Median Filtering, Derry Fitzgerald Jan 2012

Vocal Separation Using Nearest Neighbours And Median Filtering, Derry Fitzgerald

Conference papers

Recently, single channel vocal separation algorithms have been proposed which exploit the fact that most popular music can be regarded as a repeating musical background over which a locally non-repeating vocal signal is superimposed. In this paper we describe a novel vocal separator inspired by these approaches which finds the k nearest neighbours to each frame of a spectrogram of the mixture signal. The median value of these frames is then used as the estimate of the background music at the current frame. This is then used to generate a mask on the original complex-valued spectrogram before inversion to the …


Visqol: The Virtual Speech Quality Objective Listener, Andrew Hines, Jan Skoglund, Anil Kokaram, Naomi Harte Jan 2012

Visqol: The Virtual Speech Quality Objective Listener, Andrew Hines, Jan Skoglund, Anil Kokaram, Naomi Harte

Conference papers

A model of human speech quality perception has been developed to provide an objective measure for predicting subjective quality assessments. The Virtual Speech Quality Objective Listener (ViSQOL) model is a signal based full reference metric that uses a spectro-temporal measure of similarity between a reference and a test speech signal. This paper describes the algorithm and compares the results with PESQ for common problems in VoIP: clock drift, associated time warping and jitter. The results indicate that ViSQOL is less prone to underestimation of speech quality in both scenarios than the ITU standard.


Formalising Human Mental Workload As Non-Montonic Concept For Adaptive And Personalised Web-Design, Luca Longo Jan 2012

Formalising Human Mental Workload As Non-Montonic Concept For Adaptive And Personalised Web-Design, Luca Longo

Books/Book Chapters

Web Design has been evolving with Web-based systems becoming more complex and structured due to the delivery of personalised information adapted to end-users. Although information presented can be useful and well formatted, people have little mental workload available for dealing with unusable systems. Subjective mental workload assessments tools are usually adopted to measure the impact of Web-tasks upon end-users thanks to their ease of use and are aimed at supporting design practices. The Nasa Task Load Index subjective procedure has been taken as a reference technique for measuring mental workload, but it has a background in aircraft cockpits, supervisory and …


Effective Knowledge Management System Implementation In Small Organisations., Orna Nicholl Jan 2012

Effective Knowledge Management System Implementation In Small Organisations., Orna Nicholl

Dissertations

Much of the key research in the field of Knowledge Management carries an inherent set of assumptions as to the nature of the organisations under investigation, such as the fact that the organisation is a large one. As a consequence of this, Knowledge Management papers tend to focus on the distinctions such as: management-led initiatives versus grassroots initiatives, and the importance of inter-departmental communications, but for smaller organisations these types of issues are minimised or completely absent. This project will look at models and techniques from the existing body of Knowledge Management literature (with its focus on larger organisations) and …


Can A Self Assessement Tool For Environmental Controls Which Has Been Informed By Users Be Of Benefit To Potential Users, Sean Loughran Jan 2012

Can A Self Assessement Tool For Environmental Controls Which Has Been Informed By Users Be Of Benefit To Potential Users, Sean Loughran

Dissertations

This dissertation looks at the area of environmental control systems (ECS) also known as electronic aids for daily living for people with disabilities. These systems allow an individual with a disability to control devices such as a television, music player, telephone as well as a door, window or curtain controllers. A self-assessment tool was developed for potential users, which was informed by the feedback of (i) users who use or who have used environmental control systems, (ii) Enable Ireland staff who were involved in the service delivery of ECS and (iii) companies who install ECS for individuals with disabilities. These …


Recommendations For “Kiwi” Exploring Different Techniques For Recommendations In A Kazakh Online Video Website, Tair Kuanyshev Jan 2012

Recommendations For “Kiwi” Exploring Different Techniques For Recommendations In A Kazakh Online Video Website, Tair Kuanyshev

Dissertations

The aim of this project is to build a recommender system for an online website based on an empirical study using real-world data. The real world data was taken from the website Www.kiwi.kz which is an online video sharing website, providing online video, broadcast and radio to users since 2009. The research problem sought to develop the most suitable recommender system for an online video sharing website and to evaluate the effectiveness of this model on the real world data. This research attempts to develop the recommender system which will suggest possibly interesting video clips for users on an online …


Development Of Student Centred Knowledge Management System Based In A Higher Education Institution, Chong Liu Jan 2012

Development Of Student Centred Knowledge Management System Based In A Higher Education Institution, Chong Liu

Dissertations

With the emergence of a knowledge society and of information technology, knowledge has become a key resource to develop a sustained economy. It is a vital word in the Knowledge Management area (Awad & Ghaziri, 2004). Knowledge Management has also become vital to help knowledge organizations seek a competitive advantage. It also encourages members of organization to share knowledge and improve the organization‘s efficiency, performance, and competitiveness (Shin, 2004). Therefore, an increasing number of organizations have realized the necessity of knowledge management. Especially, the Higher Education Institute (HEI) as the extraordinary ―business‖ will be suitable for implementing knowledge management approaches …


Testing Mobile Web Applications For W3c Best Practice Compliance, Sean Mee Jan 2012

Testing Mobile Web Applications For W3c Best Practice Compliance, Sean Mee

Dissertations

Adherence to best practices and standards when developing mobile web applications is important to achieving a quality outcome. As smartphones and tablet PCs continue to proliferate in the consumer electronics market, businesses and individuals are increasingly turning from the native application paradigm to HTML 5-based web applications as a means of software development and distribution. With an everincreasing reliance by users on the correct functioning of such applications, the requirement for stringent and comprehensive quality assurance measures is also brought sharply into focus. This research investigates the increasing trend towards mobile web application development in the mobile software domain, and …


E-Learning And Knowledge Management: The Development Of An E-Learning System For Organisational Training, Alan Muhire Jan 2012

E-Learning And Knowledge Management: The Development Of An E-Learning System For Organisational Training, Alan Muhire

Dissertations

Information technology has major role in most successful companies and organisations around the world, most companies are using IT to reduce operation cost, while improving customer service by providing service twenty four hours, seven days a week and improving communication that helps keep pace with competitors. In most companies and organisation training is a process carried out on a regular basis; the quality of training offered to employee will be reflected on how knowledgeable the staff will become resulting in the organisation becoming more successful. As organisations and companies are currently interested in improving knowledge management, employees are equally working …


Biometric Alternatives To Captcha: Exploring Accessible Interface Options, Anita Foley Jan 2012

Biometric Alternatives To Captcha: Exploring Accessible Interface Options, Anita Foley

Dissertations

In the computing domain the relationship between accessibility and security is a complex and evolving one; accessibility attempts to ensure that as wide a range of individuals as possible are granted access to systems, whereas security attempts to restrict access only to individuals who are entitled to access those systems. A key security concern is to determine whether or not the system is being accessed by a software agent or a real human being, and a number of approaches have been developed to determine the answer to this question. This issue has been discussed throughout the history of computer science …


Investigation And Analysis Of Open Government Data In Ireland, And The Creation Of A Set Of Quality Guidelines To Aid Its Utility Within Mobile Application Development, Peadar Fitzpatrick Jan 2012

Investigation And Analysis Of Open Government Data In Ireland, And The Creation Of A Set Of Quality Guidelines To Aid Its Utility Within Mobile Application Development, Peadar Fitzpatrick

Dissertations

Governments are the custodians of vast amount of data. While some of this data may be sensitive in nature, in that it contains personal or confidential information, much of it is in the public interest. Recent years has seen the emergence of Open Government Data (OGD) where governments are now actively making their data available in open and electronically accessible formats. The motivation for the production of such data includes a desire to increase transparency but also a desire to realise the economic potential associated with re-use of this data. A key usage area for this data to date has …


An Investigation Into Obstacles Effecting The Use Of Support Technology For Accommodation Facilitation In Third Level Education, Conor Brennan Jan 2012

An Investigation Into Obstacles Effecting The Use Of Support Technology For Accommodation Facilitation In Third Level Education, Conor Brennan

Dissertations

The profile of students attending third level education in Ireland has changed over the past number of years. More non-traditional students have entered mainstream education. These non-traditional students may be mature students, students whose first language is not English and students with disabilities. In the 2010-2011 academic session 6,932 students with disabilities were enrolled in third level education. This represent 3.9%(AHEAD 2011) of all students enrolled in third level education, which constitutes a 10% increase on 2009-2010. This increase is putting pressure on an already strained system. Efforts have been made to educate and inform lecturers and teaching staff on …


Cloud Computing Adoption For Smes: Challenges, Barriers And Outcomes, Mojtaba Akbari Jan 2012

Cloud Computing Adoption For Smes: Challenges, Barriers And Outcomes, Mojtaba Akbari

Dissertations

In spite of all the excitement and fuss around cloud computing technologies in recent years, it is believed that the industry has been to some extent lagging behind when it comes to the deployment of cloud technologies and migration from legacy Information Technology (IT) infrastructure. This research aims to investigate the influential factors that impact adoption of cloud-based technologies by various organizations. More specifically, this research focuses on the behaviour of Small and Medium Enterprises (SMEs) rather than larger organizations. Such classification is crucial since the constraints applicable to SMEs are different to their larger counterparts and subsequently the decision …


The Effect Of Learning Styles And E-Learning Tools On The Training Of Ict To Digital Immigrants In Life Long Learning, Stephen Horan Jan 2012

The Effect Of Learning Styles And E-Learning Tools On The Training Of Ict To Digital Immigrants In Life Long Learning, Stephen Horan

Dissertations

The diversity of learners in the classroom has expanded significantly in the past twenty years, in a modern classroom it is unsurprising to see learners for whom English is not their first language, learners with specific learning difficulties, mature learners, learners attempting to return to work, etc., so much so that the 'typical' learner has become extinct. This research will look at the use of Information Communication Technology in Education by undertaking an investigation of how the use of ICT can aid learners, both digital natives and digital immigrants. The project will use learning styles at the core of an …


Towards Universally Designed Assistive Technology E-Learning, Karl O'Keeffe Jan 2012

Towards Universally Designed Assistive Technology E-Learning, Karl O'Keeffe

Dissertations

The aim of this dissertation is to provide Assistive Technology (AT) professionals involved in the area of education and training with a set of reusable technological tools and techniques that will enable them to increase the reach, efficiency, effectiveness and accessibility of their training through online delivery. There are a number of broadly accepted reasons why an organisation in any field might choose to make training available online or partially online (blended) rather than relying on traditional face to face methods. Of the four considered here and mentioned above, accessibility is the biggest concern in the context of AT. It …


Bs News January/February Jan 2012

Bs News January/February

Building Services Engineering

No abstract provided.


Speech Intelligibility Prediction Using A Neurogram Similarity Index Measure, Andrew Hines, Naomi Harte Jan 2012

Speech Intelligibility Prediction Using A Neurogram Similarity Index Measure, Andrew Hines, Naomi Harte

Articles

Performance Intensity functions can be used to provide additional information over measurement of speech reception threshold and maximum phoneme recognition by plotting a test subject's recognition probability over a range of sound intensities. A computational model of the auditory periphery was used to replace the human subject and develop a methodology that simulates a real listener test. The newly developed NSIM is used to evaluate the model outputs in response to Consonant-Vowel-Consonant (CVC) word lists and produce phoneme discrimination scores.


Workplace Futures: A Case Study Of An Adaptive Scenarios Approach To Establish Strategies For Tomorrow’S Workplace, Ruth Saurin Jan 2012

Workplace Futures: A Case Study Of An Adaptive Scenarios Approach To Establish Strategies For Tomorrow’S Workplace, Ruth Saurin

Doctoral

Workplace change and innovation will become critical to the organisation’s future in a dynamic, knowledge-based economy and society. As such, anticipating and managing future change is fast becoming a vital dimension underpinning the successful transition – to new work styles, patterns and locations; yet traditional workplace planning methods are rather limited in their ability to fulfil this task. This research, therefore, examines how the potential application of Futures Studies, and more specifically the Prospective
Through Scenarios process, can address this issue in order for the workplace to be actively sustained to stay effective for the organisation in the long-term.Using a …


Developing A Promo Video In Premiere Elements: A Day In Dublin, Jerome Casey Jan 2012

Developing A Promo Video In Premiere Elements: A Day In Dublin, Jerome Casey

Instructional Guides

No abstract provided.


A Novel Qos-Aware Mpeg-4 Video Delivery Algorithm Over The Lossy Ieee 802.11 Wlans To Improve The Video Quality, Tanmoy Debnath Jan 2012

A Novel Qos-Aware Mpeg-4 Video Delivery Algorithm Over The Lossy Ieee 802.11 Wlans To Improve The Video Quality, Tanmoy Debnath

Doctoral

Video traffic is bursty in nature and has different network requirements compared to other types of traffic (e.g. voice, data) in terms of bandwidth, delay, jitter, and loss etc. So it becomes important to manage video traffic on a WLAN carefully to achieve acceptable levels of Quality of Service (QoS). The unique contribution of this work is that it presents experimental and simulation studies of the performance of real video content streamed over WLAN networks. Under various test scenarios the performance of the WLAN network in terms of delay, loss, throughput etc. is analysed in the presence of background traffic. …


A Generalized Version Of An Ivantsov-Based Dendrite Growth Model Incorporating A Facility For Solute Measurement Ahead Of The Tip, Shaun Mcfadden, David Browne Jan 2012

A Generalized Version Of An Ivantsov-Based Dendrite Growth Model Incorporating A Facility For Solute Measurement Ahead Of The Tip, Shaun Mcfadden, David Browne

Articles

Extensions to the Ivantsov dendrite growth model are presented, which allow for increased solute levels in the field ahead of the dendrite tip. This model is intended for use with video-microscopy experimental results taken from synchrotron radiography sources. Ideally, the composition and composition gradient at the solid-liquid interface would be measured. However, due to the spatial resolution limitations, it is difficult to accurately measure the composition at the interface. This paper sets out an extended description of the theory where measurements ahead of the tip determine the operating conditions at the tip. This extended model of dendritic growth may be …


Using Virtual Reality Modelling To Enhance Electrical Safety And Design In The Built Environment., Martin Barrett Jan 2012

Using Virtual Reality Modelling To Enhance Electrical Safety And Design In The Built Environment., Martin Barrett

Doctoral

This thesis presents a prototype desktop virtual reality model entitled ‘Virtual Electrical Services’, to enhance electrical safety and design in the built environment. The model presented has the potential to be used as an educational tool for third level students, a design tool for industry, or as a virtual electrical safety manual for the general public. A description of the development of the virtual reality model is presented along with the applications that were developed within the model. As part of the VR development process, this research investigates the cause and effects of electrical accidents in domestic properties. This highlights …


Development Of A Robotic Platform For Upper Limb Rehabilitation, Stephen Curran, Nigel Kent, David Kennedy, James Conlon Jan 2012

Development Of A Robotic Platform For Upper Limb Rehabilitation, Stephen Curran, Nigel Kent, David Kennedy, James Conlon

Conference Papers

The aim of this project is to develop a rehabilitation robot intended for use in a non-specialised or domestic setting. Robots have been shown to have a positive effect on limb rehabilitation and developing rehabilitation robots for use outside of specialist rehabilitation centres could be beneficial in terms of access to, intensity and cost of treatment. The device is intended for the rehabilitation of the shoulder/elbow region of the upper limbs. The design requirements for such a device mean that it must be low cost, portable, robust and have a detailed focus on safety. Other areas of interest pertaining to …


Mathematical Modelling Of A Low Approach Evaporative Cooling Process For Space Cooling In Buildings, Medhi Nasrabadi, Donal Finn, Ben Costelloe Jan 2012

Mathematical Modelling Of A Low Approach Evaporative Cooling Process For Space Cooling In Buildings, Medhi Nasrabadi, Donal Finn, Ben Costelloe

Conference Papers

This paper describes a mathematical model of a low approach open evaporative cooling tower for the production of high temperature indirect cooling water (14-16°C) for use in building radiant cooling and displacement ventilation systems. There are several potential approaches to model evaporative cooling, including: the Poppe method, the Merkel method and the effectiveness-NTU (ε-NTU) method. A common assumption, applied to the Merkel and ε-NTU methods, is that the effect of change in tower water mass flow rate due to evaporation is ignored, which results in a simpler model with reduced computational requirements, but with somewhat decreasedaccuracy. In this paper, a …


Analysis Of Wind Velocity Signals For Estimating The Wave Power Density Of Ireland's Coastal Resource, Jonathan Blackledge, Eugene Dermot Coyle Professor, Derek Kearney, Ronan Mcguirk Jan 2012

Analysis Of Wind Velocity Signals For Estimating The Wave Power Density Of Ireland's Coastal Resource, Jonathan Blackledge, Eugene Dermot Coyle Professor, Derek Kearney, Ronan Mcguirk

Articles

The aim of this paper is to report on a possible correlation between the Lévy index for the wind velocity and the mean Energy Density of sea surface waves in the same location. The result is based on data obtained from six buoys located around the coast of Ireland and maintained by the Marine Institute of Ireland. These buoys provide signals on the wind velocity, wave height and wave period as well as other data on an hourly interval. Using this data, we consider the relationship between a stochastic model for the time variations in wave height that, in turn, …


Computation Of The Stochastic Volatility And Levy Index Using The Kolmogorov-Feller Equation With Applications To Carbon Price Data Analysis, Jonathan Blackledge, Marc Lamphiere, Afshin Panahi Jan 2012

Computation Of The Stochastic Volatility And Levy Index Using The Kolmogorov-Feller Equation With Applications To Carbon Price Data Analysis, Jonathan Blackledge, Marc Lamphiere, Afshin Panahi

Articles

We derive new algorithms for computing time variations in the Stochastic Volatility and the L´evy index using a standard financial price model and a Green’s function solution to the Kolmogorov-Feller equation. A principal condition upon which the algorithms are based is the Phase Only Condition which allows the Power Spectral Density Function of a financial time series (specifically the log price differences) to be taken to be a constant. The paper is composed of four component parts: (i) the Stochastic Volatility is derived and studied numerically; (ii) the Kolmogorov-Feller equation is studied and solved to provide a model for the …


Evaluation Of A Prototype Desktop Virtual Reality Model Developed To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge Jan 2012

Evaluation Of A Prototype Desktop Virtual Reality Model Developed To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge

Articles

The use of Desktop Virtual Reality (VR) systems for enhancing electrical safety and engineering design is a novel prospect for both practicing and student electrical services engineers. This innovative approach, which can be readily accessed via the World Wide Web, constitutes a marked shift in conventional learning and design techniques to a more immersive, interactive and intuitive working and learning environment. This paper initially identifies the unique characteristics of desktop web based VR technologies and highlights the educational affordances offered by working in such an environment. Subsequently, using a prototype model titled ‘Virtual Electrical Services’, a case study is carried …


Non-Gaussian Anisotropic Diffusion Processing For Medical Imagining Using The Osirix Dicom Viewer, Jonathan Blackledge, Matthew Blackledge, Jane Courtney Jan 2012

Non-Gaussian Anisotropic Diffusion Processing For Medical Imagining Using The Osirix Dicom Viewer, Jonathan Blackledge, Matthew Blackledge, Jane Courtney

Articles

Medical imaging is a fertile area for computer graphics, image processing and real time visualization. In this paper we present a method for reducing noise in CT (Computed Tomography) and MR (Magnetic Resonance) images that (in addition to other noise sources) is characteristic of the numerical procedures required to construct the images, namely, the (inverse) Radon Transform. In both cases, MR imaging in particular, an additional noise source is due to the process of diffusion thereby predicating use of the Anisotropic Diffusion method for noise suppression. This method is based on a diffusion model for noise generation where the Diffusivity …