Physical Sciences and Mathematics Commons^™

Viewer-Based Directional Querying For Mobile Applications, Keith Gardiner, James Carswell

Conference papers

With the steady and fast advancements in the integration of geographic information systems and mobile location-based services, interest in exploiting this technology for Cultural Heritage (CH) data sharing has become apparent. In this area there has been an increasing need to integrate positional information with non-positional data and add a spatial dimension to the definition of a users “context”. In this paper we describe an implementation of a viewer-based directional query processor that operates on an Oracle Spatial database. The spatial position and orientation are taken from the viewer’s perspective. Using this frame of reference a view-port is defined in …

Modelling Growth And Testing Of Multilayer Cavity Structures Incorporating Birefringent Materials, Nour-Eddine El Khachia

Masters

A simple one-dimensional photonic bandgap structure, which is also known as a Fabry-Perot Microcavity (FPM) structure was studied theoretically and experimentally. In particular this project addressed introducing an optically birefringent material in the cavity. This FPM consists of two grown regular Distributed Bragg Reflector (DBR) mirrors that can be put together as a sandwich with a space between them, which will lead to the creation of the desired cavity. Each mirror, or one-dimensional dielectric stack structure, was grown using the Vacuum Evaporation Technique and consists of multiple layers of alternating high-and low-refractive index dielectric materials arranged periodically. The project covers …

Spatial Frequency Response Of Acrylamide Based Holographic Photopolymer, Raghavendra Jallapuram, Izabela Naydenova, Vincent Toal, Suzanne Martin, Robert Howard

Conference Papers

It has been shown that photopolymers are useful in holographic optical elements [1] and holographic interferometry [2]. However, the list of potential applications increases greatly if reflection holography is possible. Reflection holography requires a material that has the potential to record high spatial frequencies. Here we studied the spatial frequency response of an acrylamide based dye sensitized holographic photopolymer. We have investigated the effect of molecular weight of the binder and concentration of crosslinking monomer on diffusion using real time monitoring of the holographic grating formation. The effect of uniform pre-exposure on diffusion was also investigated. We have also demonstrated …

Ecotoxicological Research At Dit, Maria Davoren, Colm O'Dowd, Sharon Ni Shuilleabhain

Articles

The term ecotoxicology first defined by Rene Truhart in 1969, essentially describes the study of the harmful effects of chemicals upon ecosystems.

Microtonal Systems And Guitar Composition, Michael Nielsen

Masters

This thesis focuses on the use of microtones in guitar composition. In the course of this study the physical aspects of musical sound (pitch, loudness and quality/timbre), vibrational frequencies of strings, and the theory of musical scales and tuning systems are discussed. Whole-number ratios corresponding to musical intervals within the twelve-note/equal temperament scale are calculated in relation to the overtone series for the purpose of surveying consonance and dissonance within the tempered system. These are compared to the ratios for corresponding intervals within the overtone series. Whole-number ratios are also calculated for intervals involving the microtones referred to in this …

Transition Probabilities In Kr Ii And Kr Iii Spectra, Stevan Djenize, Vladimir Milosavljevic, Milan S. Dimitrijevic

Articles

On the basis of the relative line intensity ratio (RLIR) method, transition probability values of the spontaneous emission (Einstein's A values) of 14 transitions in the singly (Kr II) and 7 transitions in doubly (Kr III) ionized krypton spectra have been obtained relatively to the reference A values related to the 435.548 nm Kr II and 324.569 nm Kr III, the most intensive transitions in the Kr II and Kr III spectra. Our Kr III transition probability values are the first data obtained experimentally using the RLIR method. A linear, low–pressure, pulsed arc operated in krypton discharge was used as …

Growth Of Well-Defined Zno Microparticles By Hydroxide Ion, Ruth Mcbride, Declan Mccormack, John Kelly

Articles

The morphology of the microcrystalline zinc oxide formed by reaction of zinc salts with sodium hydroxide depends critically on the reaction conditions. To understand this, the nature of the solid product has been probed by scanning electron microcopy (SEM) and X-ray diffraction (XRD) and the concentration of zinc remaining in the solution has been determined at regular intervals throughout the reaction. Two general preparative procedures have been followed. The first, which involves simply heating an aqueous solution containing Zn(NO3)2 (0.025 M) and sodium hydroxide (0.375 M) to 101 uC and maintaining it at that temperature for periods of up to …

Astrophysical Plasma Diagnostics Through Analysis Of Ar Iine Shape Characteristics, Vladimir Milosavljevic, Stevan Djenize

Articles

On the basis of five accurately recorded neutral argon ( ) line shapes (in the 4s-5p transition) we have recovered the basic plasma parameters i.e. electron temperature ( T) and electron density ( N) using our new line deconvolution procedure in the case of three different plasmas created in a linear, low-pressure, pulsed arc discharge. The mentioned plasma parameters have also been measured using independent experimental diagnostic techniques. An excellent agreement has been found among the two sets of obtained parameters. This recommends our deconvolution procedure for plasma diagnostic purposes, especially in astrophysics where direct measurements of the …

Experimental And Calculated Stark Widths Within The Kr I Spectrum, Vladimir Milosavljevic, Stevan Djenize, Milan S. Dimitrijevic

Articles

On the basis of the precisely recorded 20 neutral krypton (Kr I) line shapes (in the 5s−5p and 5s−6p transitions), we have obtained the basic plasma parameters, i.e., electron temperature (T) and electron density (N) using our line deconvolution procedure in a plasma created in a linear, low-pressure, pulsed arc discharge operated in krypton. The mentioned plasma parameters have also been measured using independent experimental diagnostics techniques. Agreement has been found among the two sets of the obtained parameters. This recommends our deconvolution procedure for plasma diagnostical purposes, especially in astrophysics where direct measurements of the …

Application Of A Photopolymer Material In Speckle Pattern Shearing Interferometry, Emilia Mihaylova, Izabela Naydenova, Suzanne Martin, Vincent Toal

Conference Papers

A new application of a photopolymer diffractive optical element in electronic speckle pattern shearing interferometer (ESPSI) is presented. In the first stage a holographic grating is recorded using an acrylamide based photopolymer material. Since the polymerisation process occurs during recording, the holograms are produced without any development or processing. In the second stage the holographic grating is used to produce the two sheared images in an ESPSI configuration. A ground glass screen following the grating serves the purpose of eliminating unwanted diffraction orders. The distance between the grating and the ground glass can be used to control the amount of …

Microspectrophotometry Of Respiratory Pigments, Karen Yvonne Kavanagh

Doctoral

This research thesis describes the design, construction and optical testing of three fibre-optic microspectrophotometer systems to monitor the reduction of mitochondrial respiratory pigments. The optical and biochemical characteristics of mitochondrial respiration are discussed and the current optical techniques employed in the biochemical analysis of respiratory enzymes are presented. The primary focus of this study is the system parameters surrounding the spectrophotometric determination of mitochondrial respiratory activity. Three separate fibre-optic set-ups are described, which use visible spectrophotometry to measure the reduction of mitochondrial electron carriers from a range of biological sources. Each system is based around the Ocean Optics S1000/S2000 series …

Reply To "Comment On ‘Atomic Spectral Line Free-Parameter Deconvolution Procedure’”, Vladimir Milosavljevic, Goran Poparic

Articles

We do not agree with the authors of the preceding Comment [X. Nikolic, X. Ojurovic, and X. Mijatovic, Phys. Rev. E, 67, 058401, 2003]. Our numerical procedure for the deconvolution of the theoretical asymmetric convolution integral of a Gaussian and a plasma broadened spectral line profile jA,R(λ) for spectral lines enables the determination of all broadening parameters. All broadening parameters can be determined directly from the recorded line profile of a single line, with minimal assumptions or prior knowledge. Additional experimental diagnostics are not required.

Characterisation Of Polymer-Modified Electrodes, Karl Crowley

Doctoral

In this work, two contrasting polymer-modified electrodes are investigated. Electroanalysis of lead in aqueous solutions was performed with an electrode coated with Nafion and the redox behaviour of the electronically conducting polymer, polypyrrole, was characterised. In the first study, a glassy carbon electrode coated with Nafion was used in the determination of lead through anodic stripping voltammetry (ASV). Initially the work consisted of optimising the preparation of the electrode and the experimental conditions resulting in a reproducible Nafion-modified electrode (NME) with a lifetime of several weeks. Two different stripping techniques were examined. High frequency square wave ASV was found to …

The He I 706.52 Nm Line Shape Characteristics In The Plasma Diagnostics, Vladimir Milosavljevic, Stevan Djenize

Articles

On the basis of the precisely recorded 706.52 nm He I line shape we have obtained the basic plasma parameters i.e. electron temperature (T) and electron density (N) using our new line deconvolution procedure in the case of five various plasmas created in a linear, low–pressure, pulsed arc discharge. Plasma parameters have been also measured using independent experimental diagnostical techniques. Excellent agreement was found among the two sets of the obtained parameters. This enables our deconvolution procedure to recommendation for plasma diagnostical purposes, especially in astrophysics where direct measurements of the plasma parameters (T and …

On-Line Spatial Processing Systems, James Carswell, Michela Bertolotto

Articles

On-line Spatial Processing (OLSP) delivers high performance spatial systems for the modelling and monitoring of dynamic environments. It provides an ideal solution for the management of networks, land and assets, and the real-time tracking of changing spatial systems. OLSP is server-centric, as opposed to the primarily desktop-centric world of GIS. It places spatial data at the heart of the organisation's IT systems and integrates it with business and attribute data. The result is more effective use of spatial data and improved decision support and spatial intelligence throughout the organisation.

The Physical Interactions Between Hipco Swnts And Semi-Conjugated Polymers, Sinead Keogh, Theresa Hedderman, A. Maguire, M. G. Ruther, Elizabeth Gregan, Gordon Chambers, Hugh Byrne

Conference papers

Hybrid systems of the conjugated organic polymer poly (p-phenylene vinylene-co-2,5- dioctyloxy -m-phenylene vinylene) (PmPV) and HiPco SWNT are explored using spectroscopic and thermal techniques to determine specific interactions. Vibrational spectroscopy indicates a weak interaction and this is further elucidated using Differential-Scanning Calorimetry and Temperature Dependent Raman pectroscopy. Two distinct transitions in region of -60C and + 60C are investigated.

Simulation Of Dynamic Electrochemical Processes, John Cassidy

Articles

This work is designed to introduce electrochemists in a tutorial manner to the basics of modeling of electrochemical systems based primarily on diffusion equations. There is an introduction to analytical and numerical methods with examples taken from typical electrochemical experiments. The Laplace transform is used to derive the Cottrell equation and chronopotentiometry. The response of an electrode to a Gaussian concentration profile is detailed. Laplace’s equation is solved for a simple cell to determine the potential distribution. Discrete methods are employed to calculate the current time behavior following a potential step using the explicit finite difference method. Cyclic voltammetry is …

Bridging The Ict Gap: A Study Of Uk Online Centres, John Cook, Matt Smith

Articles

An initiative to create about 6,000 UK online centres aims to bridge the gap between those in society who have access to and are able to use information and communication technologies competently, and those who do not. UK online centres can be seen as networked community learning entities, playing an expanding role in formal and informal community-based learning.

The study described below provides a detailed snapshot of what was happening in UK online centres in the first nine months of 2002. The goal was to gain an improved understanding of the social context of the centres, and issues around the …

Agent Chameleons: Virtual Agents Real Intelligence, Gregory O'Hare, Brian Duffy, Bianca Schoen-Phelan, Alan Martin, John Bradley`

Books/Book Chapters

Agent Chameleons provides virtual agents powered by real intelligence, delivering next generation autonomic entities that can seamlessly migrate, mutate and evolve on their journey between and within physical and digital information spaces.

Short-Term Effects Of Ambient Particles On Mortality In The Elderly: Results From 28 Cities In The Aphea2 Project, E. Aga, E. Samoli, G. Touloumi, K. Katsouyanni, H.R. Anderson, E. Cadum, B. Forsberg, Patrick J. Goodman, A. Goren, F. Kotesovec, B. Kriz, M. Macarol-Hiti, S. Medina, A. Paldy, C. Schindler, J. Sunyer, P. Tittanen, B. Wojtyniak, D. Zmirou, J. Schwartz

Articles

ABSTRACT: Within the framework of the APHEA2 (Air Pollution on Health: a European Approach) project, the effects of ambient particles on mortality among persons o65 yrs were investigated. Daily measurements for particles with a 50% cut-off aerodynamic diameter of 10 mm (PM10) and black smoke (BS), as well as the daily number of deaths among persons o65 yrs of age, from 29 European cities, have been collected. Data on other pollutants and meteorological variables, to adjust for confounding effects and data on city characteristics, to investigate potential effect modification, were also recorded. For individual city analysis, generalised additive models extending …

Genomic Instability Induced By Two Chemical Carcinogens, Cadmium And Nickel And By Particulate Titanium Debris From An Implant, Natasha Coen

Doctoral

It has been established that cells surviving radiation may produce descendants many cell divisions post-exposure in which, there are high incidences of chromosomal aberrations arising de novo, gene mutation and lethal mutations/delayed cell death. These effects are collectively known as genomic instability and are induced at frequencies greater than that of spontaneous mutations. Formally this syndrome ‘genomic instability’ has only been definitively proven to occur following irradiation. This leads us to the consideration that heavy metals could also induce the genomic instability phenotype, and if so, it could have implications for those exposed through their occupation, through smoking or for …

Characterization Of The Interaction Of Gamma Cyclodextrin With Single-Walled Carbon Nanotubes, Gordon Chambers, Clodagh Carroll, Garrett Farrell, Alan Dalton, Mary Mcnamara, Marc In Het Panhuis, Hugh Byrne

Articles

In this study a number of composite-like samples of ç-cyclodextrin and HiPco carbon nanotubes were prepared. The first sample was prepared by a simple grinding procedure, which has been reported to cut HiPco carbon nanotubes. The other samples were obtained via a refluxing procedure analogous to similar studies on other fullerenes and ç-cyclodextrin. The samples were analyzed using absorption and Raman spectroscopy, and differential scanning calorimetry. The results presented show clear evidence of an intermolecular interaction between ç-cyclodextrin and single-walled carbon nanotubes.

Agent Chameleons: Agent Minds And Bodies, Brian Duffy, Gregory O'Hare, Alan Martin, John Bradley, Bianca Schoen-Phelan

Conference papers

Agent design has to date concerned itself with the issues pertaining to a single body embedded in a single environment, whether virtual or real. This paper discusses the notion of an agent capable of migrating between information spaces (physical worlds, virtual reality, and digital information spaces). An architecture is presented that facilitates agent migration and mutation within such environments. This will in turn support agent

evolution the ultimate in agent adaptivity

Assessment Of The Acoustic Properties Of Common Tissue-Mimicking Test Phantoms, Jacinta Browne, K. Ramnarine, A. Watson, P. Hoskins

Articles

Ultrasound (US) test phantoms incorporating tissue-mimicking materials (TMMs) play an important role in the quality control (QC) and performance testing of US equipment. Three commercially available TMMs (ZerdineTM from CIRS Inc.; condensed-milk-based gel from Gammex RMI; urethane-rubber-based from ATS Labs) and a noncommercial agar-based TMM, were investigated. Acoustic properties were measured over the frequency range 2.25 to 15 MHz at a range of ambient temperatures (10 to 35°C). The acoustic velocity of the TMMs remained relatively constant with increasing frequency. Only the agar-based TMM had a linear increase of attenuation with frequency, with the other materials exhibiting nonlinear responses to …

Crafting A Research Paper, Ronan Fitzpatrick, Kevin O'Donnell

Conference papers

Writing research papers presents numerous different challenges, which vary from how to layout the various pages and format the text to what to include in the different sections that make up the paper. In order to clarify these issues this paper sets out guidelines and best practice approaches and demonstrates their use in the style of this paper.

A Framework To Utilise Urban Bus Data For Advanced Data Analysis, Markus Hofmann, Brendan Tierney, Margaret M. O'Mahony

Conference papers

Most urban bus operators collect detailed data on their respective transportation networks using electronic fare collection systems. However, contrary to the opinion of other service industries that this data is a valuable resource, many bus operators have tended not to fully utilise these resources. International experience suggests using innovative technologies and methodologies such as data warehousing, Online Analytical Processing (OLAP), and data mining, to derive the maximum benefit from this data. Still bus operators tend not to keep the full range of data in a form, which is easy to access or utilise, and therefore, are not able to apply …