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Full-Text Articles in Physical Sciences and Mathematics

Triangle Grouping And Structure Recovery For 3d Building Modelling And Visualization, Joe Hegarty, James Carswell Dec 2005

Triangle Grouping And Structure Recovery For 3d Building Modelling And Visualization, Joe Hegarty, James Carswell

Conference papers

Location based and spatial technologies research for the web has endless application for mobile/position content delivery (m-commerce or pcommerce). By exploiting the inherent location-based intelligence of the underling spatial component, relevant examples can include geometrically accurate and photo realistic virtual representations for: property assessments; land/marine information systems; routing information; on-line shopping; cultural heritage/tourist information/sites; etc. A major challenge for this technology is its reliance on professional developers when creating the virtual worlds used for web-based navigation of these services. This paper describes SAMATS, a Semi-Automated Modeling And Texturing System, which has the capability of producing geometrically accurate and photorealistic VR …


Samats: Edge Highlighting And Intersection Rating Explained, Joe Hegarty, James Carswell Oct 2005

Samats: Edge Highlighting And Intersection Rating 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 created 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 Modeling And Texturing System, which has the capability of producing geometrically accurate and photorealistic building models without …


Interaction Of Carbon Nanotubes With Sugar Complexes, Alan Casey, Gordon Farrell, Mary Mcnamara, Hugh Byrne, Gordon Chambers Sep 2005

Interaction Of Carbon Nanotubes With Sugar Complexes, Alan Casey, Gordon Farrell, Mary Mcnamara, Hugh Byrne, Gordon Chambers

Articles

The interaction of carbon nanotubes with soft organic molecules such as cyclodextrins and other saccarides has recently been shown to produce water soluble composites. Such systems offer considerable advantages over polymer based composites due to their biocompatibility and noncovalent coupling which can potentially preserve the unique properties of the tubes. The mechanism of interaction for such systems has been proposed to be dominated by hydrophobic and hydrophilic interactions along the surface of the tube. However efforts to characterise and rationalise such noncovalent interactions between the sugar-based materials and the carbon nanotubes have been slow to emerge. In this study a …


A Simple Electronic Speckle Pattern Interferometry System Using Holographic Optical Elements, Guntaka Tulasi Sridhar Reddy Aug 2005

A Simple Electronic Speckle Pattern Interferometry System Using Holographic Optical Elements, Guntaka Tulasi Sridhar Reddy

Doctoral

The aim of the work reported in this thesis is to develop a simple electronic speckle pattern interferometry (ESPI) system by combining holographic optical element technology with speckly interferometry. A holographic optical element is used in an ESPI system instead of the lenses, mirrors, beam splitters and beam combiners which are usually required in a conventional system. The final ESPI system consists only of a single holographic element, laser and CCD camera. Many currently available systems are complicated and consist of expensive optics that can be difficult to align. Even the simplest require several conventional optical elements to manipulate the …


Promoting Learning Through Peer Group Work, Christine O'Connor, Renli Ma Jul 2005

Promoting Learning Through Peer Group Work, Christine O'Connor, Renli Ma

Conference Papers

The session aimed to help the Summer School participants develop tasks and assessment strategies of peer group work in their own teaching.


Self And On-Selfadjoint Sturm-Liouville Operators With Exponentially Decaying Potentials, Alain Kerouanton Jun 2005

Self And On-Selfadjoint Sturm-Liouville Operators With Exponentially Decaying Potentials, Alain Kerouanton

Doctoral

In this thesis we investigate the properties of a class of linear differential operators known as Sturm-Liouville operators. Sturm-Liouville operators arise from differential equations of the form - y”+q(x)y = λy, where q is known as the potential and λ is a spectral parameter. This differential equation has been of great importance in mathematics and physics alike. We allow the potential to be real or complex valued and assume that q satisfies |q(x)|≤ce-ax, x≥0, where a >0 and c > 0. We first give a brief account of the mathematical background we will be using and then proceed to give a …


Flash Animation Project: Written Report, Peter Dee May 2005

Flash Animation Project: Written Report, Peter Dee

Dissertations

A written report about a Flash animation project to include the 3 headings of Animation Techniques, Story Telling and Audio along with a critique and an appendix. The Flash animation project is based upon one of Aesop's fables entitled 'The King's Son & the Painted Lion'.


Cardiac Relaxation Dynamics Investigated By Doppler Tissue Imaging (Dti), Gerard J. King May 2005

Cardiac Relaxation Dynamics Investigated By Doppler Tissue Imaging (Dti), Gerard J. King

Doctoral

Following an initial pilot study to explore the usefulness of Doppler tissue imaging (DTI) for the assessment of regional systolic dysfunction in the ischaemic heart, new techniques for the diagnosis of diastolic dysfunction have been developed

In the refinement of the techniques further evidence to support the existence of the early diastolic mechanism was obtained prior to assessing its clinical utility. For this the relationship between peak early diastolic mitral ring tissue velocity (EA) as a surrogate for recoil, and the acceleration of early transmitral flow (ventricular filling) was investigated in patients with diastolic dysfunction and in normal subjects. This …


Mems: Mobile Environmental Management System, Keith Gardiner, A Rizzini, James Carswell, Michela Bertolotto Apr 2005

Mems: Mobile Environmental Management System, Keith Gardiner, A Rizzini, James Carswell, Michela Bertolotto

Conference papers

This paper describes a web-based and Mobile Environmental Management System (MEMS) prototype specifically tailored to perform context-aware queries and updating of spatial datasets. Spatially enabled computing can provide situation aware assistance to both web-based and mobile users by presenting the right information at the right time, place, and situation using context-associated knowledge. Contextassociated knowledge is assembled by combining knowledge gained about information accessed in the past with the activities planned by the user, together with other situation dependencies (e.g. location) of these activities. The MEMS datasets are provided by the Canadian Department of Fisheries and Oceans (DFO) and the prototype …


Linear Electronic And Optical Processes In Fullerene Thin Films, Jonathan Moghal, Naomi Brant, Siobhan Phelan, Hugh Byrne, Gordon Chambers Jan 2005

Linear Electronic And Optical Processes In Fullerene Thin Films, Jonathan Moghal, Naomi Brant, Siobhan Phelan, Hugh Byrne, Gordon Chambers

Conference papers

The electrical properties of C60 have been extensively studied in both the solid and solution phases. The vibrational spectroscopy of C60 is predominantly molecular in character. However electronic spectroscopy reveals features, which are specific to the solid. These features have been attributed to intermolecular charge transfer states. The relative importance of these inter – and intramolecular processes in terms of their contribution to the electronic transport is discussed. Cyclic voltammetry is employed to generate charged molecular species, which also contribute to the conduction process and comparisons to optical excited states species are drawn. The cyclic voltammetry was monitored in situ …


Simple Electronic Speckle Pattern Shearing Interferometer With A Holographic Grating As A Shearing Element, Emilia Mihaylova, Izabela Naydenova, Suzanne Martin, Vincent Toal Jan 2005

Simple Electronic Speckle Pattern Shearing Interferometer With A Holographic Grating As A Shearing Element, Emilia Mihaylova, Izabela Naydenova, Suzanne Martin, Vincent Toal

Conference Papers

An optical set-up for electronic speckle pattern shearing interferometry (ESPSI) using a photopolymer diffractive optical element as a shearing element, is presented. A laser beam illuminates the object at an angle to the normal to the object surface. The holographic diffraction grating is placed in front of the object. The zero and the first order of diffraction form the image and the sheared image of the object. The images are imaged onto the CCD camera, whose optical axis coincides with the normal to the object surface. The field of view is limited only by the dimensions of the photopolymer plate. …


Characterisation Of An Acrylamide-Based Photopolymer For Data Storage Utilizing Holographic Angular Multiplexing, Hosam Sherif, Izabela Naydenova, Suzanne Martin, Colm Mcginn, Vincent Toal Jan 2005

Characterisation Of An Acrylamide-Based Photopolymer For Data Storage Utilizing Holographic Angular Multiplexing, Hosam Sherif, Izabela Naydenova, Suzanne Martin, Colm Mcginn, Vincent Toal

Articles

An acrylamide-based photopolymer formulated in the Centre for Industrial and Engineering Optics has been investigated with a view to further optimisation for holographic optical storage. Series of 18 to 30 gratings were angularly multiplexed in a volume of photopolymer layer at a spatial frequency of 1500 lines/mm. Since the photopolymer is a saturable material, an exposure scheduling method was used to exploit the entire dynamic range of the material and allow equal strength holographic gratings to be recorded. This investigation yielded the photopolymer M/# for moderately thin layers. Photopolymer temporal stability was also studied by measuring variations of material shrinkage, …


A Compact Electronic Speckle Pattern Interferometry System Using A Photopolymer Reflection Holographic Optical Element, Guntaka Tulasi Sridhar Reddy, Raghavendra Jallapuram, Vincent Toal, Izabela Naydenova, Suzanne Martin, Svetlana Mintova Jan 2005

A Compact Electronic Speckle Pattern Interferometry System Using A Photopolymer Reflection Holographic Optical Element, Guntaka Tulasi Sridhar Reddy, Raghavendra Jallapuram, Vincent Toal, Izabela Naydenova, Suzanne Martin, Svetlana Mintova

Conference Papers

A simple and compact electronic speckle pattern interferometry system using a reflection holographic optical element is presented. The reflection holographic optical element is recorded on an acrylamide based photopolymer formulated and prepared at the Centre for Industrial & Engineering Optics. Light intensity of 40mW/cm2 with an exposure time of 60 seconds was used in fabricating the holographic optical element. The vibration mode patterns of a 4 cm diameter thin circular sheet of brass metal attached to a 4 cm diameter paper cone loud speaker are presented.


Sol–Gel Derived Organic And Inorganic Hybrid Materials For Photonic Applications: Contribution To The Correlation Between The Material Structure And The Transmission In The Near Infrared Region, Mohamed Oubaha, P. Etienne And S. Calas, P. Coudray, J.M. Nedelec, Y. Moreau Jan 2005

Sol–Gel Derived Organic And Inorganic Hybrid Materials For Photonic Applications: Contribution To The Correlation Between The Material Structure And The Transmission In The Near Infrared Region, Mohamed Oubaha, P. Etienne And S. Calas, P. Coudray, J.M. Nedelec, Y. Moreau

Articles

A promising way of fabricating integrated optics components is based on the sol–gel synthesis and photocuring of organic-inorganic hybrid materials. However, the main factor limiting the development of passive devices is the propagation losses. Moreover, the possibility to compensate these attenuations by optical amplification is competed with the multiphonon relaxation associated to the presence of OH groups. To our knowledge, OH groups were always shown as the main responsible for attenuation at the telecommunication wavelengths, namely at 1310 and 1550 nm, although the matrix is composed of organic species which can contribute to absorptions in this spectral range. This paper …


The Determination Of Environmentally Important Metals In Marine Sediments, Linda Tyrrell Jan 2005

The Determination Of Environmentally Important Metals In Marine Sediments, Linda Tyrrell

Masters

Surface sediment samples were collected at sites within the Rockall Through at water depth ranges from 700 – 2774 metres. The study area was predefined by the availability of samples. Samples were collected by the British Geological Survey during their gravity core survey undertaken in 1998. Methods were optimised and validated for lead, cadmium, chromium, copper, nickel, zinc, lithium and aluminium using atomic absorption spectroscopy following total digestion, and for mercury, using cold vapour atomic fluorescence spectroscopy following partial digestion. The measured metal concentration were normalised to Li to compensate for the influence of natural variability in the concentration of …


Structural Property Relationships In Conjugated Polymers, Patrick Lynch, Luke O'Neill, J. Whelan, Mary Mcnamara, Hugh Byrne Jan 2005

Structural Property Relationships In Conjugated Polymers, Patrick Lynch, Luke O'Neill, J. Whelan, Mary Mcnamara, Hugh Byrne

Articles

The synthesis of a series of PPV derivative polymers by the Wittig-Horner reaction is described. The structure of each polymer is varied and the effects of these variations on the optical properties is explored. The effects of alkyloxy side chains is observed between the PPV derivatives Poly(-p-phenylvinylene-co-2,5-bis-octyloxy phenylvinylene.) PPV-OPV and Poly (para-2,5-bis-(n-octyloxy)-phenylvinylene) POPV. The phenyl units of the soluble PPV derivative POPV are replaced by alternate naphthyl units in the polymer Poly(2,5-bis(n-octyloxy)-1,4-phenylene vinylene-1,5-bis(n-octyloxy)-2,6-naphthylene vinylene) POPN-ONV and then fully by naphthyl units in Poly(2,6-bis-(n-octyloxy)-1,5-NaphthyleneVinylene) PONV. The addition of alkyloxy sidechains served to red shift the fluorescence emission as expected. The systematic …


Correlation Of Spectroscopic And Biochemical Assays Postionising Radiation Exposure In Human Skin Cell Analogues, Aidan Meade, Hugh Byrne, Fiona Lyng Jan 2005

Correlation Of Spectroscopic And Biochemical Assays Postionising Radiation Exposure In Human Skin Cell Analogues, Aidan Meade, Hugh Byrne, Fiona Lyng

Conference papers

Raman spectroscopy, as an evaluation of the products of ionising radiation exposure in biological systems, has been utilised mainly in the evaluation of the impact of exposure in tissue, cellular constituents and live animals. It has also been recently demonstrated that Raman spectroscopy can demonstrate key spectroscopic changes in the live cell associated with significant apoptotic and necrotic chemical damage. The present preliminary work utilises Raman spectroscopy at 514.5 nm to evaluate the results of exposure to -rays in HaCaT cells from a Co-60 therapy source, in tandem with other biological assays. The results demonstrate that a number of spectral …


Electroabsorption Studies Of Structurally Modified Fullerene Thin Films, Gerald Farrell, Gordon Chambers, Hugh Byrne Jan 2005

Electroabsorption Studies Of Structurally Modified Fullerene Thin Films, Gerald Farrell, Gordon Chambers, Hugh Byrne

Conference papers

Ultraviolet (UV/Vis) and Electroabsorption (EA) spectroscopy is used to examine and differentiate between intermolecular and intra molecular excited state species in fullerene films. Charge Transfer (CT) states are identified at 2.4 eV and 2.7 eV and dipole moments are calculated. Thermal annealing of C60 films is monitored in situ using absorption spectroscopy and electroabsorption spectroscopy. Recorded spectra display both some temperature dependent and partially irreversible effects, indicating the occurrence of an annealing process. EA shows that the CT states associated with the transferring an electron from the HOMO of one molecule located at the (0,0,0) position to the LUMO of …


The Potential Of Vibrational Spectroscopy In The Early Detection Of Cervical Cancer: An Exciting Emerging Field, Eoghan O'Faolain, Mary Hunter, Joe Byrne, Peter Kelehan, Hugh Byrne, Fiona Lyng Jan 2005

The Potential Of Vibrational Spectroscopy In The Early Detection Of Cervical Cancer: An Exciting Emerging Field, Eoghan O'Faolain, Mary Hunter, Joe Byrne, Peter Kelehan, Hugh Byrne, Fiona Lyng

Conference papers

The application of vibrational spectroscopy to disease diagnosis is a relatively new, rapidly evolving scientific field. Techniques such as Raman and infrared spectroscopy have shown great promise in this regard over the past number of years. This study directly compared Raman spectroscopy and synchrotron infrared (SR-IR) spectroscopy on parallel cervical cancer samples. Both frozen and dewaxed formalin fixed paraffin preserved tissue sections were examined. Both tissue types produced good quality Raman and SR-IR spectra, although the lesser processed, frozen tissue sections displayed the most detailed spectra. Spectroscopy was shown capable of discriminating between different cell types in normal cervical tissue. …


Conformal Properties And Baecklund Transform For The Associated Camassa-Holm Equation, Rossen Ivanov Jan 2005

Conformal Properties And Baecklund Transform For The Associated Camassa-Holm Equation, Rossen Ivanov

Articles

Integrable equations exhibit interesting conformal properties and can be written in terms of the so-called conformal invariants. The most basic and important example is the KdV equation and the corresponding Schwarz-KdV equation. Other examples, including the Camassa-Holm equation and the associated Camassa-Holm equation are investigated in this paper. It is shown that the B¨acklund transform is related to the conformal properties of these equations. Some particular solutions of the Associated Camassa-Holm Equation are discussed also.


Investigation Of The Effect Of Subcutaneous Fat On Image Quality Performance Of 2d Conventional Imaging And Tissue Harmonic Imaging, Jacinta Browne, Amanda Watson, Peter Hoskins, Alex Elliott Jan 2005

Investigation Of The Effect Of Subcutaneous Fat On Image Quality Performance Of 2d Conventional Imaging And Tissue Harmonic Imaging, Jacinta Browne, Amanda Watson, Peter Hoskins, Alex Elliott

Articles

Tissue harmonic imaging (THI) has been reported to improve contrast resolution, tissue differentiation and overall image quality in clinical examinations. However, a study carried out previously by the authors (Browne et al. 2004) found improvements only in spatial resolution and not in contrast resolution or anechoic target detection. This result may have been due to the homogeneity of the phantom. Biologic tissues are generally inhomogeneous and THI has been reported to improve image quality in the presence of large amounts of subcutaneous fat. The aims of the study were to simulate the distortion caused by subcutaneous fat to image quality …


Generating Estimates Of Classification Confidence For A Case-Based Spam Filter, Sarah Jane Delany, Padraig Cunningham, Donal Coyle, Anton Zamolotskikh Jan 2005

Generating Estimates Of Classification Confidence For A Case-Based Spam Filter, Sarah Jane Delany, Padraig Cunningham, Donal Coyle, Anton Zamolotskikh

Conference papers

Producing estimates of classification confidence is surprisingly difficult. One might expect that classifiers that can produce numeric classification scores (e.g. k-Nearest Neighbour, Na¨ıve Bayes or Support Vector Machines) could readily produce confidence estimates based on thresholds. In fact, this proves not to be the case, probably because these are not probabilistic classifiers in the strict sense. The numeric scores coming from k-Nearest Neighbour, Na¨ıve Bayes and Support Vector Machine classifiers are not well correlated with classification confidence. In this paper we describe a case-based spam filtering application that would benefit significantly from an ability to attach confidence predictions to positive …


Vibrational Coupling In Conjugated Π Systems With A View To Optimization Of Fluorescence Yield Through Phonon Confinement, Luke O'Neill, Patrick Lynch, Mary Mcnamara, Hugh Byrne Jan 2005

Vibrational Coupling In Conjugated Π Systems With A View To Optimization Of Fluorescence Yield Through Phonon Confinement, Luke O'Neill, Patrick Lynch, Mary Mcnamara, Hugh Byrne

Conference papers

A series of π conjugated systems were studied by absorption, photoluminescence and vibrational spectroscopy. As is common for these systems, a linear relationship between the positioning of the absorption and photoluminescence maxima plotted against inverse conjugation length is observed. The relationships are in good agreement with the simple particle in a box method, one of the earliest descriptions of the properties of one-dimensional organic molecules. In addition to the electronic transition energies, it was observed that the Stokes shift also exhibited a well-defined relationship with increasing conjugation length, implying a correlation between the electron-vibrational coupling and chain length. This correlation …


Interaction Of Single Walled Carbon Nanotubes With Starch-Based Systems, Alan Casey, Gerald Farrell, Mary Mcnamara, Hugh Byrne, Gordon Chambers Jan 2005

Interaction Of Single Walled Carbon Nanotubes With Starch-Based Systems, Alan Casey, Gerald Farrell, Mary Mcnamara, Hugh Byrne, Gordon Chambers

Conference papers

The interaction of carbon nanotubes with soft organic molecules such as cyclodextrins and other saccharides has recently been shown to produce water-soluble composites. Such systems offer considerable advantages over polymer based composites due to their biocompatibility and noncovalent coupling which can potentially preserve the unique properties of the tubes. The mechanism of interaction of such systems has been proposed to be dominated by hydrophobic and hydrophilic interactions along the surface of the tube. In this study a number of composite systems have been formed with HiPco carbon nanotubes using starch and starch based polymers. The first composite formed with starch …


Use Of Raman Spectroscopy In The Investigation Of Debundling Of Single Walled Carbon Nanotubes, Elizabeth Gregan, Sinead Keogh, Theresa Hedderman, Gordon Chambers, Hugh Byrne Jan 2005

Use Of Raman Spectroscopy In The Investigation Of Debundling Of Single Walled Carbon Nanotubes, Elizabeth Gregan, Sinead Keogh, Theresa Hedderman, Gordon Chambers, Hugh Byrne

Conference papers

Samples of raw nanotubes are compared to those deposited from solutions to examine separation of nanotube bundles. Single wall nanotubes bundles produced by the arc-discharge and HiPco methods were solubilised in toluene, DMF and 1,2 dichloroethane. Resonant Raman spectroscopy was used to determine if debundling of the tubes sample occurred. The results showed some degree of debundling, best for the 1,2 dichloroethane solvent, which also shows long term solubility.


Efficacy Of Innovative Anti-Microbial Decontamination Of Minimally Processed Vegetables, Christina Busquets I Tortosa Jan 2005

Efficacy Of Innovative Anti-Microbial Decontamination Of Minimally Processed Vegetables, Christina Busquets I Tortosa

Masters

Chlorine has widespread use commercially as a disinfectant wash for raw vegetables. However, it is an extremely corrosive gas and it may have severe health and environmental implications. The aim of this thesis was to find safe, alternative decontamination treatments for ready-to-eat Iceberg lettuce. The efficacy of 1% acetic acid, 2% citric acid; calcium lactate concentrations of 0.5%, 1.5%, 2.5% and 3% at wash temperature of 4,25 and 50°C, ozone alone (1 mg 1-1) and in combination with calcium lactate (2.5%) were compared with chlorine as decontaminating treatments. Microbiological analyses were performed following decontamination treatments using the pour plate method …


On Torsion-Free Crawley Groups, Brendan Goldsmith, A. L. S. Corner, R. Gobel Jan 2005

On Torsion-Free Crawley Groups, Brendan Goldsmith, A. L. S. Corner, R. Gobel

Articles

The notion of a Crawley p-group is well known in Abelian group theory. In this present work, a corresponding concept is introduced for torsion-free groups. The principal result, which uses the set-theoretic notions of the diamond and Martin’s axiom, establishes an independence result for N1-free Crawley groups.


Minimal Modules Over Valuation Domains, Brendan Goldsmith, P. Zanardo Jan 2005

Minimal Modules Over Valuation Domains, Brendan Goldsmith, P. Zanardo

Articles

Let R be a valuation domain. We say that a torsion-free R-module is minimal if it is isomorphic to all its submodules of finite index. Here, the usual concept of finite index for groups is replaced by the more appropriate (for module theory) definition: a submodule H of the module G is said to be of finite index in G if the quotient G/H is a finitely presented torsion module. We investigate minimality in various settings and show inter alia that over a maximal valuation domain, all torsion-free modules are minimal. Constructions of non-minimal modules are given by utilizing realization …


An Explicit Mapping Between The Frequency Domain And The Time Domain Representations Of Nonlinear Systems, Marissa Condon, Rossen Ivanov Jan 2005

An Explicit Mapping Between The Frequency Domain And The Time Domain Representations Of Nonlinear Systems, Marissa Condon, Rossen Ivanov

Articles

Explicit expressions are presented that describe the input-output behaviour of a nonlinear system in both the frequency and the time domain. The expressions are based on a set of coefficients that do not depend on the input to the system and are universal for a given system. The anharmonic oscillator is chosen as an example and is discussed for different choices of its physical parameters. It is shown that the typical approach for the determination of the Volterra Series representation is not valid for the important case when the nonlinear system exhibits oscillatory behaviour and the input has a pole …


On The Integrability Of A Class Of Nonlinear Dispersive Wave Equations, Rossen Ivanov Jan 2005

On The Integrability Of A Class Of Nonlinear Dispersive Wave Equations, Rossen Ivanov

Articles

We investigate the integrability of a class of 1+1 dimensional models describing nonlinear dispersive waves in continuous media, e.g. cylindrical compressible hyperelastic rods, shallow water waves, etc. The only completely integrable cases coincide with the Camassa-Holm and Degasperis-Procesi equations.