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Self-Authentication Of Audio Signals By Chirp Coding, Jonathan Blackledge, Eugene Coyle
Self-Authentication Of Audio Signals By Chirp Coding, Jonathan Blackledge, Eugene Coyle
Conference papers
This paper discusses a new approach to ‘watermarking’ digital signals using linear frequency modulated or ‘chirp’ coding. The principles underlying this approach are based on the use of a matched filter to provide a reconstruction of a chirped code that is uniquely robust in the case of signals with very low signal-to-noise ratios. Chirp coding for authenticating data is generic in the sense that it can be used for a range of data types and applications (the authentication of speech and audio signals, for example). The theoretical and computational aspects of the matched filter and the properties of a chirp …
Metal-Induced Bystander Effects: Mechanism And Implicationis., Nicola Cogan
Metal-Induced Bystander Effects: Mechanism And Implicationis., Nicola Cogan
Doctoral
The radiation-induced bystander effect is a phenomenon known to occur post irradiation, characterised by the induction of biological effects in unirradiated cells as a result of receiving signals from irradiated cells or their culture medium. Chemicalinduced bystander effects are poorly characterised and there are no reports of a bystander effect induced by metals. Heavy metals and in particular chromium (VI) are known to cause persistent genomic instability. For the first time, this study provides evidence that a short, low-dose exposure of human fibroblasts to chromium (VI) causes a bystander effect in human fibroblasts that persists for at least thirty days …
Stochastic Particle Acceleration In The Lobes Of Giant Radio Galaxies, Stephen O'Sullivan, Brian Reville, Andrew Taylor
Stochastic Particle Acceleration In The Lobes Of Giant Radio Galaxies, Stephen O'Sullivan, Brian Reville, Andrew Taylor
Articles
We investigate the acceleration of particles by Alfv ́en waves via the second-order Fermi process in the lobes of giant radio galaxies. Such sites are candidates for the accelerators of ultra-high-energy cosmic rays (UHECR). We focus on the nearby Fanaroff–Riley type I radio galaxy Centaurus A. This is motivated by the coincidence of its position with the arrival direction of several of the highest energy Auger events. The conditions necessary for consistency with the acceleration time-scales predicted by quasi-linear theory are reviewed. Test particle calculations are performed in fields which guarantee electric fields with no component parallel to the local …
Nonideal Magnetohydrodynamic Turbulent Decay In Molecular Clouds, Turlough Downes, Stephen O'Sullivan
Nonideal Magnetohydrodynamic Turbulent Decay In Molecular Clouds, Turlough Downes, Stephen O'Sullivan
Articles
It is well known that non-ideal magnetohydrodynamic effects are important in the dynamics of molecular clouds: both ambipolar diffusion and possibly the Hall effect have been identified as significant. We present the results of a suite of simulations with a resolution of 512-cubed of turbulent decay in molecular clouds incorporating a simplified form of both ambipolar diffusion and the Hall effect simultaneously. The initial velocity field in the turbulence is varied from being super-Alfvénic and hypersonic, through to trans-Alfvénic but still supersonic.
The Very Basics Of Sustainability - An Alternative Viewpoint, Jim Mcgovern
The Very Basics Of Sustainability - An Alternative Viewpoint, Jim Mcgovern
Other resources
This paper examines the context and meaning of the term ‘sustainability’, the factors that determine and govern climate on Earth, the population of the Earth and its trends and influencers, the requirements for sustaining life and the options that are available to humankind. Some viewpoints are presented that are alternative to ‘conventional alternative’ thinking. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’ and also argues that humankind needs to face …
The Very Basics Of Sustainability - An Alternative Viewpoint (Slides With Audio) (Large File! To Speed Up Download, Right-Click On "Download" Link To Save To Own Pc.), Jim Mcgovern
Other resources
This presentation sets out the very basics of ‘sustainability’, although a definition of sustainability is not attempted. Some of the very basics are the context in which the Earth and humankind exist in space and time, the Earth’s climate, the Earth’s population and humankind’s options and choices. The author advocates keeping an open mind on all available options, including the use of oil, gas, coal, tar sands, carbon capture and sequestration, nuclear power etc., as well as the technologies that are more widely considered ‘green’. The author also argues that, in addressing the challenges that humankind faces, globally concerted effort …
Assessment Of The Embodied Co2eq In Buildings Towards A Sustainable Building Design And Construction, Adolf Acquaye, Aidan Duffy, Biswajit Basu
Assessment Of The Embodied Co2eq In Buildings Towards A Sustainable Building Design And Construction, Adolf Acquaye, Aidan Duffy, Biswajit Basu
Conference Papers
Research studies have shown that the initial energy embodied in a building can be as much as 67% of the operational energy over a 25 year period. With growing global concerns over material and resource consumption and the emissions of CO2 into the atmosphere, the energy embodied in buildings constructed in town and cities becomes important and one of the key issues that needs to be tackled in the design stages in order to strive towards sustainable buildings design. In this paper, a hybrid embodied carbon dioxide equivalent (CO2eq) methodology used to assess the CO2eq embodied in buildings is presented. …
The Potential Use Of Slow-Down Technology To Improve Pronounciation Of English For International Communication, Bunny Richardson
The Potential Use Of Slow-Down Technology To Improve Pronounciation Of English For International Communication, Bunny Richardson
Doctoral
The focus of this research is on oral communication between L1 (first language) and L2 (second language) English users - to determine whether an algorithm which slows down speech can increase the intelligibility of speech between interlocutors for EIC (English for International Communication). The slow-down facility is a CALL tool which slows down speech without tonal distortion. It allows English language learners more processing time to hear individual phonemes as produced in the stream of connected speech, to help them hear and produce phonemes more accurately and thus more intelligibly. The study involved five tests, all concerned with the intelligibility …
Evolution Versus Revolution As A Strategy For Thin Client Acceptance: Case Study, Paul Doyle, Mark Deegan, Ciaran O'Driscoll
Evolution Versus Revolution As A Strategy For Thin Client Acceptance: Case Study, Paul Doyle, Mark Deegan, Ciaran O'Driscoll
Conference papers
Thin Clients have evolved from simple text based CRT dumb terminal devices in the 1960s, into a sophisticated architecture encompassing hardware, software, networks and protocols. However despite this recent evolution the Thin Client model has yet to re-emerge as a relevant design in an IT industry where Fat Clients (desktops and laptops) thrive. This paper describes two case studies performed within the Technological University Dublin School of Computing, focused on the issue of student acceptance of this technology. The first case study provides a dedicated single service Thin Client implementation, while the second case study adopts a process of coexistence …
A Context-Aware Approach Based On Self-Organizing Maps To Study Web-Users' Tendencies From Their Behaviour, Luca Longo, Stephen Barrett
A Context-Aware Approach Based On Self-Organizing Maps To Study Web-Users' Tendencies From Their Behaviour, Luca Longo, Stephen Barrett
Conference papers
In the context of a highly volatile web of uneven quality, the identification of content deemed valuable by end users is of paramount importance. Where page content undergoes rapid change, this issue is particularly challenging. Web browsing activity represents a unique source of context by which the value of web pages can be determined via an assessment of individual user interactions, such as scrolling, clicking, saving and so forth. Over time, this data set forms a pattern of activity which can be mined for meaning. In this paper we present an approach to web content, based on Kohonen mapping, used …
Development Of Renal Phantoms For The Evaluation Of Current And Emerging Ultrasound Technology, Deirdre King
Development Of Renal Phantoms For The Evaluation Of Current And Emerging Ultrasound Technology, Deirdre King
Doctoral
The primary aim of this project was to develop novel anatomically realistic renal phantoms for the evaluation of current and emerging ultrasound techniques capable of diagnosing all grades of renal artery stenosis. Renal artery stenosis is considered the most common cause of potentially curable secondary hypertension which if left untreated can lead to renal failure. Its early detection is very important as it offers the possibility of various drug treatments, which are considerably less invasive and poses less risk to the patient. Computer-aided modelling techniques were used to generate a range of anatomically realistic phantoms of the renal artery from …
Applying Computational Models Of Spatial Prepositions To Visually Situated Dialog, John D. Kelleher, Fintan Costello
Applying Computational Models Of Spatial Prepositions To Visually Situated Dialog, John D. Kelleher, Fintan Costello
Articles
This article describes the application of computational models of spatial prepositions to visually situated dialog systems. In these dialogs, spatial prepositions are important because people often use them to refer to entities in the visual context of a dialog. We first describe a generic architecture for a visually situated dialog system and highlight the interactions between the spatial cognition module, which provides the interface to the models of prepositional semantics, and the other components in the architecture. Following this, we present two new computational models of topological and projective spatial prepositions. The main novelty within these models is the fact …
Characterisation Of The Humidity And Temperature Responses Of A Reflection Hologram Recorded In Acrylamide-Based Photopolymer, Izabela Naydenova, Raghavendra Jallapuram, Vincent Toal, Suzanne Martin
Characterisation Of The Humidity And Temperature Responses Of A Reflection Hologram Recorded In Acrylamide-Based Photopolymer, Izabela Naydenova, Raghavendra Jallapuram, Vincent Toal, Suzanne Martin
Articles
The humidity and temperature responses of a reflection hologram recorded in a self-processing photopolymer layer have been characterised by measurement of the position of the maximum intensity in the spectral response of the hologram. It has been demonstrated that such a hologram can be used for indication of the relative humidity (RH) in a specific temperature range. The operational range and reversibility of the holograms have been characterised in a controlled humidity and temperature environment. The humidity studies were carried out in the range from 10 to 80% RH and the temperature range under study was 15 – 50 ºC.
Covariant Relativistic Quantum Mechanics Analysis Of A Linearly Accelerated Scalar Particle, Karol Mcdonald
Covariant Relativistic Quantum Mechanics Analysis Of A Linearly Accelerated Scalar Particle, Karol Mcdonald
Doctoral
A covariant formalism of Relativistic Quantum Mechanics is demonstrated, through it's de- velopment and application. The Relativistic Case is shown to follow a similar structure to the established Non-Relativistic formalism. Reasons for preferring the new covariant formalism over the established method are presented. Solutions to the case of a scalar particle in a one-dimensional field are presented. The Relativistic Energy Eigenfunction is derived. Results are generated from initial Gaussian states via a Green's Function method. A Green's Function for the system is derived and applied. The solution to the Quantum System is shown to follow a scaled version of the …
Tight Lower Bound For The Sparse Travelling Salesman Problem, Fredrick Mtenzi
Tight Lower Bound For The Sparse Travelling Salesman Problem, Fredrick Mtenzi
Conference papers
The Sparse Travelling Salesman Problem (Sparse TSP) which is a variant of the classical Travelling Salesman Problem (TSP) is the problem of finding the shortest route of the salesman when visiting cities in a region making sure that each city is visited at least once and returning home at the end. In the Sparse TSP, the distance between cities may not obey the triangle inequality; this makes the use of algorithms and formulations designed for the TSP to require modifications in order to produce near-optimal results. A lower bound for optmisation problems gives us the quality guarantee of the near-optimal …
Samats: Texture Extraction Explained, Joe Hegarty, James Carswell
Samats: Texture Extraction Explained, Joe Hegarty, James Carswell
Conference papers
The creation of detailed 3D buildings models, and to a greater extent the creation of entire city models, has become an area of considerable research over the last couple of decades. The accurate modeling of buildings has LBS (Location Based Services) applications in entertainment, planning, tourism and e-commerce to name just a few. Many modeling systems deployed to date require manual correspondences to be made across the image set in order to determine the models 3D structure. This paper describes SAMATS, a Semi-Automated Modelling and Texturing System, which has the capability of producing geometrically accurate and photorealistic building models without …
Swcnt Suppress Inflammatory Mediator Responses In Human Lung Epithelium In Vitro, Eva Herzog, Hugh Byrne, Maria Davoren, Anke-Gabriele Lenz, Albert Duschl, Gertie Janneke Oostingh
Swcnt Suppress Inflammatory Mediator Responses In Human Lung Epithelium In Vitro, Eva Herzog, Hugh Byrne, Maria Davoren, Anke-Gabriele Lenz, Albert Duschl, Gertie Janneke Oostingh
Articles
Single walled carbon nanotubes have gained enormous popularity due to a variety of potential applications which will ultimately lead to increased human and environmental exposure to these nanoparticles. This study was carried out in order to evaluate the inflammatory response of immortalised and primary human lung epithelial cells (A549 and NHBE) to single walled carbon nanotube samples (SWCNT). Special focus was placed on the mediating role of lung surfactant on particle toxicity. The toxicity of SWCNT dispersed in cell culture medium was compared to that of nanotubes dispersed in dipalmitoylphosphatidylcholine (DPPC, the main component of lung lining fluid). Exposure was …
Spectroscopic Imaging Of Quantum Dot Cellular Interactions, Lorenzo Salford
Spectroscopic Imaging Of Quantum Dot Cellular Interactions, Lorenzo Salford
Masters
Quantum dots (QDs) are a diverse class of engineered nanomaterials that have great potential for use as agents in imaging, diagnostics and drug-delivery because of their intense and photostable fluorescence. Advances in the field of nanotoxicology, however, have recently identified potential risks and hazards associated with exposure to QDs. The main purpose of this research is to investigate the capabilities of a synergistic range of different techniques, including cytotoxicity assays, confocal microscopy and vibrational spectroscopy, to probe their interaction with Biological systems. With the combination of these techniques it is hoped to understand the mechanisms of the interaction of QDs …
Online Support And Online Assessment For Teaching And Learning Chemistry, Claire M. Mcdonnell, Natasa Brouwer
Online Support And Online Assessment For Teaching And Learning Chemistry, Claire M. Mcdonnell, Natasa Brouwer
Books/Book chapters
In this chapter, examples of innovative approaches that use educational technology to support active learning in chemistry lectures, tutorials and laboratory sessions are considered. The scope of the chapter is limited to blended learning. The strengths and weaknesses of e-learning are examined and the options available for online assessment using electronic tests and e-portfolios are discussed. In addition to the literature references provided in the chapter, several examples of good practice involving the implementation of information and communication technology for chemistry teaching in higher education are incorporated. A list of online resources for lecturers is also included.
Double-Glazing Interferometry, Vincent Toal, Emilia Mihaylova
Double-Glazing Interferometry, Vincent Toal, Emilia Mihaylova
Articles
This note describes how white light interference fringes can be seen by observing the Moon through a double-glazed window. White light interferometric fringes are normally observed only in a well-aligned interferometer whose optical path difference is less than the coherence length of the light source, which is approximately one micrometer for white light. Obtaining such fringes in a Michelson interferometer is not a trivial task.1 The interferometer is typically illuminated with a monochromatic source and the path length difference adjusted with a wedge angle between the interferometer mirrors so that five or six vertical fringes are visible, indicating nearly equal …
Poisson Structures Of Equations Associated With Groups Of Diffeomorphisms, Rossen Ivanov
Poisson Structures Of Equations Associated With Groups Of Diffeomorphisms, Rossen Ivanov
Conference papers
A class of equations describing the geodesic flow for a right-invariant metric on the group of diffeomorphisms of Rn is reviewed from the viewpoint of their Lie-Poisson structures. A subclass of these equations is analogous to the Euler equations in hydrodynamics (for n = 3), preserving the volume element of the domain of fluid flow. An example in n = 1 dimension is the Camassa-Holm equation, which is a geodesic flow equation on the group of diffeomorphisms, preserving the H1 metric.
Two Component Integrable Systems Modelling Shallow Water Waves, Rossen Ivanov
Two Component Integrable Systems Modelling Shallow Water Waves, Rossen Ivanov
Conference papers
Our aim is to describe the derivation of shallow water model equations for the constant vorticity case and to demonstrate how these equations can be related to two integrable systems: a two component integrable generalization of the Camassa-Holm equation and the Kaup - Boussinesq system.
A Mobile Ecg Monitoring System With Context Collection, Jin Peng Li, Damon Berry, Richard Hayes
A Mobile Ecg Monitoring System With Context Collection, Jin Peng Li, Damon Berry, Richard Hayes
Conference Papers
Preventative health management represents a shift from the traditional approach of reactive treatment-based healthcare towards a proactive wellness-management approach where patients are encouraged to stay healthy with expert support when they need it, at any location and any time. This work represents a step along the road towards proactive, preventative healthcare for cardiac patients. It seeks to develop a smart mobile ECG monitoring system that requests and records context information about what is happening around the subject when an arrhythmia event occurs. Context information about the subject’s activities of daily living will, it is hoped, provide an enriched data set …
Archetype Alignment: A Two-Level Driven Semantic Matching Approach To Interoperability In The Clinical Domain, Damon Berry, Jesus Bisbal
Archetype Alignment: A Two-Level Driven Semantic Matching Approach To Interoperability In The Clinical Domain, Damon Berry, Jesus Bisbal
Conference Papers
Semantic interoperability between electronic health record systems and other information systems in the health domain implies agreement about the structure and the meaning of the information that is communicated. There are still a number of similar but different EHR system approaches. Some of the newer approaches adopt the two-layer model approach where a generic reference model is constrained by archetypes into valid clinical concepts which can be exchanged. The meaning of the concepts that are represented by an archetype can be conveyed by embedding codes from a commonly recognised terminology at appropriate points in the archetype. However, as the number …
Macular Pigment Levels Increase Following Blue-Light Filtering Intraocular Lens Implantation., James Loughman
Macular Pigment Levels Increase Following Blue-Light Filtering Intraocular Lens Implantation., James Loughman
Other Resources
No abstract provided.
Simple Versatile Shearing Interferometer Suitable For Measurements On A Microscopic Scale, Emilia Mihaylova, Vincent Toal
Simple Versatile Shearing Interferometer Suitable For Measurements On A Microscopic Scale, Emilia Mihaylova, Vincent Toal
Articles
Microelectromechanical systems (MEMS) behave differently from massive samples. Conventional testing and inspection techniques usually fail at the microscale. Recently there has been an increasing interest in the application of optical techniques for microstructure testing, because they are high-resolution, non-contact, full-field, fast and relatively inexpensive. New interferometric systems, which are suitable for microscopic optical metrology, are of interest for engineering and industrial applications. A modified electronic speckle pattern shearing interferometer (ESPSI) with a very simple shearing device has been designed for metrology applications on the microscale. The shearing device consists of two partially reflective glass plates. The reflection coefficients of the …
Optical And Holographic Characteristics Of Photopolymer Layers, Temenujka Yovcheva, Izabela Naydenova, Ivanka Vlaeva, Suzanne Martin, Vincent Toal, Simeon Sainov
Optical And Holographic Characteristics Of Photopolymer Layers, Temenujka Yovcheva, Izabela Naydenova, Ivanka Vlaeva, Suzanne Martin, Vincent Toal, Simeon Sainov
Articles
In the present work the optical and holographic characteristics of acrylamide-based photopolymer layers are studied. For the first time the refractive index change of a liquid acrylamide photopolymer due to exposure at 532 nm is obtained using a critical angle laser micro-refractometer. The 30 mm thick solid photopolymer films are prepared by casting on glass substrates. Bragg holographic gratings with spatial frequencies of 710 mm-1, 1050 mm-1 and 1600 mm-1 are recorded using a diode laser operating at 532 nm wavelength. The diffraction efficiency dependence on the exposure energy is investigated. The obtained results are compared with the Stetson holographic …
Silver Doped Perfluoropolyether-Urethane Coatings: Antibacterial Activity And Surface Analysis, Niall Stobie, Brendan Duffy, Steven Hinder, Patrick Mchale, Declan Mccormack
Silver Doped Perfluoropolyether-Urethane Coatings: Antibacterial Activity And Surface Analysis, Niall Stobie, Brendan Duffy, Steven Hinder, Patrick Mchale, Declan Mccormack
Articles
The colonisation of clinical and industrial surfaces with pathogenic microorganisms has prompted increased research into the development of effective antibacterial and antifouling coatings. There is evidence that implanted biomedical surfaces coated with metallic silver can be inactivated by hysiological fluids, thus reducing the bioactivity of the coating. In this work, we report the biofilm inhibition of Staphylococcus epidermidis using a roomtemperatureprocessedsilver dopedperfluoropolyether-urethane coating. The release of silver ions from these fluoropolymers over a six-day period inhibited bacterial encrustation – as observed by scanning electron microscopy (SEM). X-ray photoelectron spectroscopy (XPS) analysis indicated differences in carbon, fluorine and sodium surface composition …
One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat
One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat
Articles
No abstract provided.
An Assessment Of Epiphytic Lichens, Lichen Diversity And Environmental Quality In The Semi-Natural Woodlands Of Knocksink Wood Nature Reserve, Enniskerry, County Wicklow, Lenka Mulligan
Masters
This research work adapted and applied a recently developed method for assessing epiphytic lichen species diversity to the Irish semi-natural woodlands of Knocksink Wood Nature Reserve, Enniskerry, County Wicklow. The study focused on the differences that arise in relation to acidophilous oak woodland (Blechno-Quercetum petraeae) versus ash-hazel woodland (Corylo-Fraxinetum). The research also addressed differences in relation to the mixed oak-ash-hazel woodland located in Knocksink Wood and the neighbouring woodland at the Powerscourt Waterfall. The frequency of occurrence of lichen species on a defined portion of tree bark was used as an estimate of diversity and to evaluate the degree of …