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Full-Text Articles in Physical Sciences and Mathematics

Phenomenographic Study Of Students’ Problem Solving Approaches In Physics, Laura Walsh, Robert Howard, Brian Bowe Jan 2007

Phenomenographic Study Of Students’ Problem Solving Approaches In Physics, Laura Walsh, Robert Howard, Brian Bowe

Articles

This paper describes ongoing research investigating student approaches to quantitative and qualitative problem solving in physics. This empirical study was conducted using a phenomenographic approach to analyze data from individual semistructured problem solving interviews with 22 introductory college physics students. The main result of the study is a hierarchical set of categories that describe the students’ problem solving approaches in the context of introductory physics.


Rate And Equilibrium Constants For Reactions Of Coordinated Cyclohexadienyl Cations, Martin Galvin Jan 2007

Rate And Equilibrium Constants For Reactions Of Coordinated Cyclohexadienyl Cations, Martin Galvin

Doctoral

In this work, the nucleophilic reactions of ironcarbonyl coordinated cyclohexadienyl cations with water and hydroxide to produce the corresponding coordinated arene hydrate analogues was examined. These nucleophilic reactions are a key step in a synthetic route to convert arene cis-dihydrodiols to their trans-isomers via their tricarbonyliron coordinated complexes. The arene trans-dihydrodiols produced have significant potential to be used as chiral buildings blocks in synthetic chemistry and have the advantage that they are more stable then their cis-analogues The first cation studied was (п5-cyclohexadienyl)dicarbonyl-triphenylphosphineiron. An equilibrium constant, pKr, for formation of the coordinated arene hydrate (п4-exo-5-hydroxy-1,3-cyclohexadience)dicarbonyltriphenylphosphine-iron, from this coordinated cation was …


A Theory And Practice Of Website Engagibility, Ronan Fitzpatrick Jan 2007

A Theory And Practice Of Website Engagibility, Ronan Fitzpatrick

Doctoral

This thesis explores the domain of website quality. It presents a new study of website quality - an abstraction and synthesis, a measurement methodology, and analysis - and proposes metrics which can be used to quantify it. The strategy employed involved revisiting software quality, modelling its broader perspectives and identifying quality factors which are specific to the World Wide Web (WWW). This resulted in a detailed set of elements which constitute website quality, a method for quantifying a quality measure, and demonstrating an approach to benchmarking eCommerce websites. The thesis has two dimensions. The first is a contribution to the …


Development Of A Novel Modular Mid-Infrared Sensor For The In-Situ Detection Of The Btex Compounds In Water, Raymond Mccue Jan 2007

Development Of A Novel Modular Mid-Infrared Sensor For The In-Situ Detection Of The Btex Compounds In Water, Raymond Mccue

Doctoral

This research thesis describes the design, construction and testing of a novel modular mid-infrared fibre optic sensing system for the detection of hydrocarbons in water. It is the adverse effects to these hydrocarbon pollutants on flora and fauna that has led to the development of sensing systems for their detection and quantification. The key sensor design feature, its modularity, utilises simple low cost commercially available optical components, which are inherently suited to construct compact rugged sensing systems to perform in-situ measurements which are ideally preferred for environmental sensing. The various laboratory-based prototypes constructed weee calibrated for two target analytes over …


Incompressible And Compressible Boundary Layers On A Fibre In The Melt Spinning Process, John Harding Jan 2007

Incompressible And Compressible Boundary Layers On A Fibre In The Melt Spinning Process, John Harding

Doctoral

This thesis seeks to investigate shear stress on and heat transfer from the surface of a fibre in the industrial process of melt spinning. Melt spinning is the process whereby molten polymer materials are extruded through the holes of a device known as a spinneret to create continuous filaments of polymer. Fibres manufactured in this way are used in applications as diverse as fashion and clothing, to telecommunications. The magnitude ofthe shear stress on the fibre surface, and also the rate of heat transfer from the fibre to the surrounding environment are of major importance to the overall quality of …


A New Approach To The Toxicity Testing Of Carbon-Based Nanomaterials: The Clonogenic Assay, Eva Herzog, Alan Casey, Fiona Lyng, Gordon Chambers, Hugh Byrne, Maria Davoren Jan 2007

A New Approach To The Toxicity Testing Of Carbon-Based Nanomaterials: The Clonogenic Assay, Eva Herzog, Alan Casey, Fiona Lyng, Gordon Chambers, Hugh Byrne, Maria Davoren

Articles

The cellular toxicity of three types of carbon nanoparticles, namely HiPco® single-walled carbon nanotubes (SWCNT), arc dischargeSWCNTand Printex 90 carbon black nanoparticles,was studied on three different cell models including the human alveolar carcinoma epithelial cell line (A549), the normal human bronchial epithelial cell line (BEAS-2B) and the human keratinocyte cell line (HaCaT) using the clonogenic assay. Carbon nanomaterials are known to interact with colorimetric indicator dyes frequently used in cytotoxicity assays. By employing the clonogenic assay, any such interactions could be avoided, allowing a more reliable method for the in vitro toxicity assessment of carbon-based nanoparticles. It could be shown …


Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn Jan 2007

Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Articles

Meteorological enthalpy analysis of temperate and maritime climates above latitude 45°N suggests that the water-side evaporative cooling technique has considerable unrealised potential with contemporary “high temperature” building cooling systems—such as chilled ceilings and displacement ventilation. As low approach conditions are the key to exploiting the cooling potential of the ambient air, thermal performance at such conditions needs to be investigated. To address the research issues, an industrial scale test rig, based on a low approach open cooling tower and plate heat exchanger and designed to maximise evaporative cooling potential, has been constructed. The thermal effectiveness of such systems (as a …


Modelling Of Re-Absorption Losses In Quantum Dot Solar Concentrators, Manus Kennedy Jan 2007

Modelling Of Re-Absorption Losses In Quantum Dot Solar Concentrators, Manus Kennedy

Conference Papers

A Monte-Carlo ray-trace model has been developed which allows the calculation of the optical efficiency (ηopt) and concentration ratio (CR) values of a Quantum Dot Solar Concentrator (QDSC). In this paper, ηopt values have been calculated using a range of material refractive indices, material attenuation coefficients, and quantum dot (QD) quantum efficiencies (QE). Spectral overlap leads to reabsorption of light in the device which leads to increased escape cone losses and QD QE losses. Results have been obtained for ideal QD spectra, where there is 0% overlap between QD emission and absorption spectra (and hence no re-absorption), and for real …


An Experiment Using A Simple Photoassisted Fuel Cell Designed To Remediate Simulated Wastewater, John Cassidy, Faisa Touati, Kevin Mcguigan Jan 2007

An Experiment Using A Simple Photoassisted Fuel Cell Designed To Remediate Simulated Wastewater, John Cassidy, Faisa Touati, Kevin Mcguigan

Articles

Work in photochemistry work peaked in the 1980’s where there was the prospect of using sunlight shining on suspensions of titanium dioxide in order to catalytically cleave water into hydrogen and oxygen [1-5]. In this way a clean and efficient method of producing hydrogen as a fuel was envisaged. However, there was a requirement to use a rather high energy light to achieve the splitting and it was not as efficient with visible light[5]. Doped TiO2 layers have been used in a three electrode system for formic acid degradation[6]. In this work, the system uses an electrode coated with TiO2 …


A Note On Clean Abelian Groups, Brendan Goldsmith, P. Vamos Jan 2007

A Note On Clean Abelian Groups, Brendan Goldsmith, P. Vamos

Articles

Nicholson defined a ring to be clean if every element is the sum of a unit and an idempotent. A module is clean if its endomorphism algebra is clean. We show that torsion-complete Abelian p-groups are clean and characterize the clean groups among the class of totally projective p-groups. An example is given of a clean p-group which is neither totally projective nor torsion- complete


Optimising The Ratio Of Horseradish Peroxidase And Glucose Oxidase On A Bienzyme Electrode: Comparison Of A Theoretical And Experimental Approach, Dana Mackey, Anthony Killard, Adriano Ambrosi, Malcolm Smyth Jan 2007

Optimising The Ratio Of Horseradish Peroxidase And Glucose Oxidase On A Bienzyme Electrode: Comparison Of A Theoretical And Experimental Approach, Dana Mackey, Anthony Killard, Adriano Ambrosi, Malcolm Smyth

Articles

This study compares the behaviour of an electrochemical enzyme biosensor with a theoretical analysis based on a mathematical model and numerical simulation. The biosensor is based on a bi-enzyme channelling configuration, employing the enzymes glucose oxidase and horseradish peroxidase, with direct electron transfer of horseradish peroxidase at a conducting polymer electrode. This was modelled by a system of partial differential equations and boundary conditions representing convective and diffusive transport of the substrates glucose and hydrogen peroxide, as well as reaction kinetics of the bienzyme electrode. The main parameter investigated was the ratio of the two immobilised enzymes, with the aim …


Conformal And Geometric Properties Of The Camassa-Holm Hierarchy, Rossen Ivanov Jan 2007

Conformal And Geometric Properties Of The Camassa-Holm Hierarchy, Rossen Ivanov

Articles

Integrable equations with second order Lax pair like KdV and Camassa-Holm (CH) exhibit interesting conformal properties and can be written in terms of the so-called conformal invariants (Schwarz form). These properties for the CH hierarchy are discussed in this ontribution. The squared eigenfunctions of the spectral problem, associated to the Camassa-Holm equation represent a complete basis of functions, which helps to describe the Inverse Scattering Transform (IST) for the Camassa-Holm hierarchy as a Generalised Fourier Transform (GFT). Using GFT we describe explicitly some members of the CH hierarchy, including integrable deformations for the CH equation. Also we show that solutions …


Frequency Based Incremental Attribute Selection For Gre., John D. Kelleher Jan 2007

Frequency Based Incremental Attribute Selection For Gre., John D. Kelleher

Conference papers

The DIT system uses an incremental greedy search to generate descriptions, similar to the incremental algorithm described in (Dale and Reiter, 1995). The selection of the next attribute to be tested for inclusion in the description is ordered by the absolute frequency of each attribute in the training corpus. Attributes are selected in descending order of frequency (i.e. the attribute that occurred most frequently in the training corpus is selected first). Where two or more attributes have the same frequency of occurrence the first attribute found with that frequency is selected. The type attribute is always included in the description. …


Colour Doppler Spatial Resolution Performance Testing, Jacinta Browne, Ian Brown, Peter Hoskins, Amanda Watson, Alex Elliott Jan 2007

Colour Doppler Spatial Resolution Performance Testing, Jacinta Browne, Ian Brown, Peter Hoskins, Amanda Watson, Alex Elliott

Articles

No abstract available


Matrix Effects, Development Of Clean-Up And Lc-Techniques Contributing Towards A Reference Lcms Method For The Analysis Of Lipophilic Marine Toxins, Mairead Anne Mcelhinney Jan 2007

Matrix Effects, Development Of Clean-Up And Lc-Techniques Contributing Towards A Reference Lcms Method For The Analysis Of Lipophilic Marine Toxins, Mairead Anne Mcelhinney

Masters

The most widely used reference method in Europe for the detection and monitoring of lipophilic marine toxins is the Mouse Bioassay (MBA) as first described by Yasumoto et al., (1978). The MBA offers a good level of protection to human health and is capable of detecting the overall toxicity of previously known toxins. However, there are drawbacks associated with the use of the MBA as it is both expensive and time consuming and can give false positives due to interferences (Suzuki et al, 1976). The problems associated with the original mouse bioassay have led to several modifications (Yasumoto et al, …


An Approach To Unification Using A Linear Systems Model For The Propagation Of Broad-Band Signals, Jonathan Blackledge Jan 2007

An Approach To Unification Using A Linear Systems Model For The Propagation Of Broad-Band Signals, Jonathan Blackledge

Articles

We review the inhomogeneous scalar Helmholtz equation in three-dimensions and the scattering of scalar wavefields from a scatterer of compact support. An asymptotic solution is then considered representing the effect of the frequency approaching zero when a ‘wavefield’ reduces to a ‘field’. The characteristics of ultra-low frequency Helmholtz scattering are then considered and the physical significance discussed of a model that is based on the scattering of Helmholtz wavefields over a broad frequency spectrum. This is equivalent to using a linear systems approach for modelling the propagation, interaction and detection of broad-band signals and provides an approach to the classification …


Diffusion And Fractional Diffusion Based Models For Multiple Light Scattering And Image Analysis, Jonathan Blackledge Jan 2007

Diffusion And Fractional Diffusion Based Models For Multiple Light Scattering And Image Analysis, Jonathan Blackledge

Articles

This paper considers a fractional light diffusion model as an approach to characterizing the case when intermediate scattering processes are present, i.e. the scattering regime is neither strong nor weak. In order to introduce the basis for this approach, we revisit the elements of formal scattering theory and the classical diffusion problem in terms of solutions to the inhomogeneous wave and diffusion equations respectively. We then address the significance of these equations in terms of a random walk model for multiple scattering. This leads to the proposition of a fractional diffusion equation for modelling intermediate strength scattering that is based …


Hologram-Based Humidity Indicator For Domestic And Packaging Applications, Izabela Naydenova, Raghavendra Jallapuram, Vincent Toal, Suzanne Martin Jan 2007

Hologram-Based Humidity Indicator For Domestic And Packaging Applications, Izabela Naydenova, Raghavendra Jallapuram, Vincent Toal, Suzanne Martin

Conference Papers

A passive indicator for Relative Humidity based on a photopolymer recorded hologram has been developed. The indicator works on the principle that the wavelength reconstructed by a reflection hologram is dependent on the spacing between the fringe planes of the hologram. As the Relative Humidity changes, the hologram swells or shrinks and the apparent colour of the reconstructed image changes. The response time, operational range and reversibility of the indicator have been studied in a controlled humidity environment. Response times from less than a minute to tens of minutes depending on the holograms physical properties have been measured. Indicators with …


Torsion-Free Groups And Modules With The Involution Property, Brendan Goldsmith, C. Meehan, S.L. Wallutis Jan 2007

Torsion-Free Groups And Modules With The Involution Property, Brendan Goldsmith, C. Meehan, S.L. Wallutis

Articles

An Abelian group or module is said to have the involution property if every endomorphism is the sum of two automorphisms, one of which is an involution. We investigate this property for completely decomposable torsion-free Abelian groups and modules over the ring of -adic integers.


Use Of The Mitsunobu Reaction In The Synthesis Of Orthogonally Protected A,B-Diaminopropionic Acids, Fintan Kelleher, Keith Ó Proinsias Jan 2007

Use Of The Mitsunobu Reaction In The Synthesis Of Orthogonally Protected A,B-Diaminopropionic Acids, Fintan Kelleher, Keith Ó Proinsias

Articles

Orthogonally protected a,b-diaminopropionic acids have been synthesised in good yields by the reaction of N-trityl L-serine esters with N-substituted sulfonamides under Mitsunobu reaction conditions (DEAD, PPh3, THF). The best isolated yields were obtained when N-Boc p-toluenesulfonamide was used as the nitrogen nucleophile precursor in the Mitsunobu reaction. Subsequently, the N-trityl group was efficiently replaced with the more stable allyloxycarbonyl (alloc) group.


A Novel Processing Route For The Production Of Nanoparticulate Zinc Oxide Using An Isophthalate Precursor, Grainne Duffy, Declan Mccormack, Suresh Pillai Jan 2007

A Novel Processing Route For The Production Of Nanoparticulate Zinc Oxide Using An Isophthalate Precursor, Grainne Duffy, Declan Mccormack, Suresh Pillai

Articles

Zinc oxide nanoparticles have been processed from a novel isophthalate precursor. In contrast to those processed from an oxalate precursor, this material exhibits three-dimensional, non-directional aggregation behaviour.

Such non-directional aggregation of uniaxial crystallites may allow for the production of structures with a higher proportion of catalytically active surfaces than can be prepared through conventional sol–gel methods. XRD,

FTIR, TEM and SEM were used to characterize the synthesized materials.

Zinc oxide particles synthesized by using isophthalic acid (C6H4-1,3-(COOH)2) are found to be slightly smaller than the previously reported materials prepared through chelation with oxalic acid (H2C2O2・2H2O).


Catching The Drift : Using Feature-Free Case-Based Reasoning For Spam Filtering., Sarah Jane Delany, Derek Bridge Jan 2007

Catching The Drift : Using Feature-Free Case-Based Reasoning For Spam Filtering., Sarah Jane Delany, Derek Bridge

Conference papers

n this paper, we compare case-based spam filters, focusing on their resilience to concept drift. In particular, we evaluate how to track concept drift using a case-based spam filter that uses a feature-free distance measure based on text compression. In our experiments, we compare two ways to normalise such a distance measure, finding that the one proposed in [1] performs better. We show that a policy as simple as retaining misclassified examples has a hugely beneficial effect on handling concept drift in spam but, on its own, it results in the case base growing by over 30%. We then compare …


Using Computer Vision To Create A 3d Representation Of A Snooker Table For Televised Competition Broadcasting, Hao Guo, Brian Mac Namee Jan 2007

Using Computer Vision To Create A 3d Representation Of A Snooker Table For Televised Competition Broadcasting, Hao Guo, Brian Mac Namee

Conference papers

The Snooker Extraction and 3D Builder (SE3DB) is designed to be used as a viewer aid in televised snooker broadcasting. Using a single camera positioned over a snooker table, the system creates a virtual 3D model of the table which can be used to allow audiences view the table from any angle. This would be particularly useful in allowing viewers to determine if particular shots are possible or not. This paper will describe the design, development and evaluation of this system. Particular focus in the paper will be given to the techniques used to recognise and locate the balls on …


Proceedings Of The 4th Acl-Sigsem Workshop On Prepositions At Acl-2007., Fintan Costello, John D. Kelleher, Martin Volk Jan 2007

Proceedings Of The 4th Acl-Sigsem Workshop On Prepositions At Acl-2007., Fintan Costello, John D. Kelleher, Martin Volk

Conference papers

This volume contains the papers presented at the Fourth ACL-SIGSEM Workshop on Prepositions. This workshop is endorsed by the ACL Special Interest Group on Semantics (ACL-SIGSEM), and is hosted in conjunction with ACL 2007, taking place on 28th June, 2007 in Prague, the Czech Republic.


Mems Mobile Gis: A Spatially Enabled Fish Habitat Management System, Andrea Rizzini, Keith Gardiner, Michela Bertolotto, James Carswell Dec 2006

Mems Mobile Gis: A Spatially Enabled Fish Habitat Management System, Andrea Rizzini, Keith Gardiner, Michela Bertolotto, James Carswell

Conference papers

Spatially enabled computing can provide assistance to both web-based and mobile users by exploiting positional information and associated contextual knowledge. The Mobile Environmental Management System (MEMS) is a proof of concept prototype that has been developed in order to simplify administrative duties of biologists at the Department of Fisheries and Oceans (DFO), Canada. MEMS aims to deliver contextaware functionality aided by visualization, analysis and manipulation of spatial and attribute datasets. The resulting application delivers a set of functions and services that aids the DFO’s biologists in making everyday management decisions


To Evaluate The Effects Of The Introduction Of A Smoke-Free Environment On The Lung Function Of Bar Workers In Dublin, Michele Agnew Nov 2006

To Evaluate The Effects Of The Introduction Of A Smoke-Free Environment On The Lung Function Of Bar Workers In Dublin, Michele Agnew

Masters

It has long been recognised that exposure to environmental tobacco smoke (ETS) causes respiratory and cardio-vascular disease. A ban, prohibiting smoking in the workplace, was sanctioned by the Irish government and came into effect on 29 March, 2004. Bar staff were an ideal group to study the health effects of the introduction of this ban. Methods Workers were recruited through their Trade Union, Mandate, and 81 participated in the pre-ban phase of testing between September 2003 and March 2004. They attend the Respiratory Laboratory in St. James’s Hospital and underwent lung function tests and measurement of exhaled carbon monoxide (CO). …


Serious Gordon Using Serious Games To Teach Food Safety In The Kitchen, Brian Mac Namee, Pauline Rooney, Patrick Lindstrom, Andrew Ritchie, Frances Boylan, Greg Burke Nov 2006

Serious Gordon Using Serious Games To Teach Food Safety In The Kitchen, Brian Mac Namee, Pauline Rooney, Patrick Lindstrom, Andrew Ritchie, Frances Boylan, Greg Burke

Papers, presentations and other resources

This paper will describe the development of Serious Gordon, an interactive digital game developed to tech the basics of kitchen food safety to workers in industries dealing with food. The motivations driving the development of the game will be described as will the development process itself. An initial evaluation of the game, from both a technical and pedagogical point of view, will be presented as will conclusions on the viability of using a commercial game engine for the purpose of developing educational games.


Icing Location Client, Seamus Rooney, Keith Gardiner, James Carswell Oct 2006

Icing Location Client, Seamus Rooney, Keith Gardiner, James Carswell

Articles

The ICiNG (Innovative Cities for Next Generation) project is researching a multi-modal, multi-access model of e-Government. It develops the concept of a “thin-skinned City” that will be sensitive to both the citizen and the environment through the use of mobile devices, universal access gateways, social software and environmental sensors. Intelligent infrastructure will enable a Public Administration Services layer and a Communities layer. Communities will interact with the infrastructure to avail of ICiNG services created by the administration, and will also create their own information-based services.


The Use Of Task Based Mood-Induction Procedures To Generate High Quality Emotional Assets, Brian Vaughan, Charlie Cullen, Spyros Kousidis, Yi Wang, Ciaran Mcdonnell, Dermot Campbell Oct 2006

The Use Of Task Based Mood-Induction Procedures To Generate High Quality Emotional Assets, Brian Vaughan, Charlie Cullen, Spyros Kousidis, Yi Wang, Ciaran Mcdonnell, Dermot Campbell

Conference papers

Detecting emotion in speech is important in advancing human-computer interaction, especially in the area of speech synthesis. This poster details experimental procedures based on Mood Induction Procedure 4, using performance related tasks to engender natural emotional responses in participants. These tasks are aided or hindered by the researcher to illicit the desired emotional response. These responses will then be recorded and their emotional content graded to form the basis of an emotional speech corpus. This corpus will then be used to develop a rule-set for basic emotional dimensions in speech.


An Event-Driven Approach To Computerizing Clinical Guidelines Using Xml, Bing Wu, Essam Mansour, Kudakwashe Dube, Jianxin Li Sep 2006

An Event-Driven Approach To Computerizing Clinical Guidelines Using Xml, Bing Wu, Essam Mansour, Kudakwashe Dube, Jianxin Li

Conference Papers

Clinical events form the basis of patient care practice. Their computerization is an important aid to the work of clinicians. Clinical guidelines or protocols direct clinicians and patients on when and how to handle clinical problems. Thus, clinical guidelines are an encapsulation of clinical events. Hence, an event-driven approach to computerizing the management of clinical guidelines is worthy of investigation. In our framework, called SpEM, the main clinical guideline management dimensions are specification, execution, and manipulation. This paper presents an event-driven approach, within the context of the SpEM framework, to manage clinical guidelines. The event-driven approach is based on the …