Physical Sciences and Mathematics Commons^™

Comparison Of Auto-Adjusting And Fixed Level Continuous Positive Airway Pressure Therapy In Patients With Mild To Moderate Obstructive Sleep Apnoea Hypopnoea Syndrome, Geraldine Nolan

Masters

Obstructive Sleep Apnoea Hypopnoea syndrome (OSAHS) is a potentially serious medical disorder associated with increased morbidity and mortality. It is estimated to affect 4% of males and 2% of females between the ages of forty and sixty. Nasal continuous positive airway pressure (CPAP) is the first choice treatment for this condition and it is extremely effective at controlling OSAHS. However, not all patients can tolerate this therapy, in particular those within the mild to moderate category, and there are also many others who are unable to comply with the minimum usage requirements of at least four hours every night. A …

Evaluating The Use Of In Vitro Bioassays For The Ecotoxicological Assessment Of Irish Estuarine Sediments, Sharon Ni Shuilleabhain

Doctoral

Sediments, as a repository for persistent anthropogenic contaminants, have the potential to cause deleterious effects in the aquatic environment. Particular attention to the quality of sediment is, therefore, warranted in the ecotoxicological risk assessment of aquatic systems. An assessment methodology combining chemical, ecotoxicological and ecological evaluations in a hierarchial test strategy, where toxicological significant and complexity increases with the tiers, is recommended for a thorough appraisal of sediment toxicity. The aim of the present study was to assess the potential of in vitro bioassays to be employed as screening tools got Tier 1 ecotoxicity evaluation of Irish estuarine sediments. Chemical …

Stark Width And Shift Of The Neutral Argon 425.9 Nm Spectral Line, Vladimir Milosavljevic, Vida Zigman, Stevan Djenize

Articles

The Stark parameters, the width (W) and the shift (d), of the neutral argon (Ar I) 425.9 nm spectral line have been studied in a linear, low-pressure, optically thin pulsed arc discharge. The line shapes are measured in three different plasmas at about 16,000 K electron temperature (T) and about 7.0×10²² m⁻³ electron density (N). The separate electron and ion contributions to the total Stark width (W_t), i.e. W_e and W_i, as well as to the total Stark shift (d_t), i.e. …

On The Dressing Method For The Generalised Zakharov-Shabat System, Rossen Ivanov

Articles

The dressing procedure for the Generalised Zakharov-Shabat system is well known for systems, related to sl(N) algebras. We extend the method, constructing explicitly the dressing factors for some systems, related to orthogonal and symplectic Lie algebras. We consider ’dressed’ fundamental analytical solutions with simple poles at the prescribed eigenvalue points and obtain the corresponding Lax potentials, representing the soliton solutions for some important nonlinear evolution equations.

Direct Least-Squares Ellipse Fitting, Jane Courtney, Annraoi Depaor

Conference Papers

Many biological and astronomical forms can be best represented by ellipses. While some more complex curves might represent the shape more accurately, ellipses have the advantage that they are easily parameterised and define the location, orientation and dimensions of the data more clearly. In this paper, we present a method of direct least-squares ellipse fitting by solving a generalised eigensystem. This is more efficient and more accurate than many alternative approaches to the ellipse-fitting problem such as fuzzy c-shells clustering and Hough transforms. This method was developed for human body modelling as part of a larger project to design a …

Applications Of Mobile Computing For Fish Species At Risk Management, James Carswell, Keith Gardiner, Michela Bertolotto, Nick Mandrak

Conference papers

This paper describes the on-going development of 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 …

Investigation Of The Diffusion Processes In Self-Processing Acrylamide-Based Photopolymer System, Izabela Naydenova, Raghavendra Jallapuram, Robert Howard, Suzanne Martin, Vincent Toal

Articles

Results from the investigation of the diffusion processes in a dry acrylamide-based photopolymer system are presented. The investigation is carried out in the context of experimental work on optimization of the high spatial frequency response of the photopolymer. Tracing the transmission holographic grating dynamics at short times of exposure is utilized to measure diffusion coefficients. The results reveal that two different diffusion processes contribute with opposite sign to the refractive index modulation responsible for the diffraction grating build up. Monomer diffusion from dark to bright fringe areas increases the refractive index modulation. It is characterized with diffusion constant D0=1.6E-7 cm2/s. …

Interaction Of Carbon Nanotubes With Saccharides: A Possible Route To Biocompatible Composites, Alan Casey, Jonathan Moghal, Gerald Farrell, Hugh Byrne, Gordon Chambers

Conference papers

Inclusion complexes of saccharides and HiPco Carbon Nanotubes (HCNT) were formed, resulting in water soluble complexes. These complexes were then characterised using a variety of spectroscopic techniques. Raman spectroscopy was used to probe changes in the vibrational character of both the host and guest species and also to assess if any selectivity of tube diameter occurred. UV-Vis-NIR and circular dichroic spectroscopies were used to assess the effect of inclusion on the electronic properties of the tubes. Spectroscopic analysis of these species showed clear evidence of an intermolecular interaction between the host material and the HCNT.

Self-Assembled Arrays Of Zno Nanoparticles And Their Application As Varistor Materials, Suresh Pillai, Declan Mccormack, John Kelly, Raghavendra Ramesh

Articles

Linear arrays of ZnO nanoparticles have been successfully prepared by a simple sol–gel condensation reaction involving chemical modifiers, followed by drying (80oC) and calcination (500 oC). The calcined material (nanoarray ZnO) is composed of approximately spherical nanoparticles of average diameter 21+/-3 nm, selfassembled to form arrays extending in length to 2–4 mm. The morphology of the ZnO is found to depend sensitively on the amounts of chemical modifiers present. In their absence the ZnO produced (nano-ZnO) is an unstructured agglomerate of nanoparticles. The mechanism for formation of these linear arrays has been investigated by examining the intermediates formed at 80 …

Optimisation Of Organic Materials For Laser Applications, Kieran P. Henderson

Masters

This project sets out to investigate the variations of the optical properties of organic conjugated polymers with a view towards understanding the transition from isolated molecule (solution) to the solid state. The polymer poly9p-phenylene vinylene-co-2,5-dioctyloxy-m-phenylene vinylene) (PmPV) is chosen as it is of interest for both light emitting and nanotube composite applications. As a model compound, 2,5-dioctoxy-p-distrylbenzene, termed the trimer, is employed for comparison. The objective are to characterize the effect of the environment, using solvent and concentration dependent studies, on the optical properties of the polymer and to compare the results for the more complex polymeric system to the …

Wireless Spatio-Semantic Transactions On Multimedia Datasets, James Carswell, Keith Gardiner, Marco Neumann

Conference papers

Advances in spatially enabled semantic computing can provide situation aware assistance for mobile users. This intelligent and context-aware technology presents the right information at the right time, place and situation by exploiting semantically referenced data for knowledge discovery. The system takes advantage of new metadata standards to enable semantic, user, and device adapted transactions on multimedia datasets. Information accessed in the past and the activities planned by the user, the situation dependencies (e.g. location) of these activities are used to infer future information requirements. The focus of this paper describes an application of the above functionalities for performing mobile context-aware …

Application Of Photopolymer Holographic Gratings, Emilia Mihaylova, Izabela Naydenova, Hosam Sherif, Suzanne Martin, Vincent Toal

Conference Papers

Two optical set-ups for electronic speckle pattern shearing interferometry (ESPSI) using photopolymer diffractive optical elements are presented. Holographic gratings are recorded using an acrylamide based photopolymer material. Since the polymerisation process occurs during recording, the holograms are produced without any development or processing. In both ESPSI systems the photopolymer gratings are used to shear the image. In the first ESPSI system only one grating is used in combination with a sheet of ground glass. The distance between the grating and the ground glass can be used to control the amount of the shear. The sheared images on the ground glass …

Investigation Of The Photoinduced Surface Relief Modulation In Acrylamide-Based Photopolymer, Izabela Naydenova, Emilia Mihaylova, Suzanne Martin, Vincent Toal

Conference Papers

A surface relief diffraction grating is inscribed in acrylamide photopolymer by holographic recording with spatial frequency below 300 l/mm. The periodic surface modulation appears in addition to a volume phase holographic grating. Due to the nature of the presented photopolymerisable material the gratings are induced by light only and no post-processing is required. An investigation of the dependance of the amplitude of the photoinduced relief modulation on spatial frequency of recording and on sample thickness has been carried out utilising white light interferometry. A model of the mechanism of surface relief formation is proposed on the basis of the measured …

The Exterior Orientation Of Aerial Imagery Using Existing Orthoimagery And Terrain Models:A Performance Test, Finnian O'Cionnaith

Masters

In every part of the world the rate of map revision is alarmingly low when compared to the rate of change of many human influenced surface features. There is therefore a requirement to regularly gather up-to-date information about surface features and to incorporate changes in maps both quickly and effectively before it becomes history. When an aerial photograph is taken, it contains errors one category of which is caused by the aircraft taking the photograph being tilted. This aerial photograph by itself is of little commercial value. Accurate maps cannot be created from it, its use in GIS (Geographical Information …

Empowering Agents Within Virtual Environments, Alan Martin, Brian Duffy, Gregory O'Hare, Bianca Schoen-Phelan, John Bradley

Conference Papers

An agent’s embodiment within a virtual environment refers to its representation, and defines its capabilities, within the environment. This paper presents a system for the strong integration of embodiment with the agent’s deliberative mechanism. This mechanism is based upon the Belief-Desire-Intention (BDI) paradigm, and allows the agent to deliberate directly upon the location and animation of its embodiment. This fusion then provides the agent with the ability to freely mutate its embodied form to best suit the task at hand. At the same time, care must be taken to preserve the agents’ sense of self, so that users have a …

A University Online Portal For Enterprise Learning Communities, Marco Neumann, Ciaran Mcdonnell, Deirdre Hogan, Carol Reinsford, Stefan Decker

Conference papers

This paper describes the Programme for University Industry Interface Semantic Web Portal project that supports the efforts in enterprise training units to upskill the employee in the company and facilitates the creation and reuse of knowledge in online communities. The main purpose of this project is to support on-line learning communities and monitor the changing needs and skills of the work force in enterprise environments.

Increased Frequency Of The Mthfr A1298c Mutation In An Irish Population, Cathal Mccarthy, Fergus Ryan, Joseph Vaughan

Articles

No abstract provided.

On The Cotorsion Images Of The Baer-Specker Group, Brendan Goldsmith, T. Kelly, S, Wallutis

Articles

No abstract available

Dit-Call: Naturally Speaking But Slow, Dermot Campbell, Marty Meinardi, Bunny Richardson, Eugene Coyle, Olivia Donnellan, Pak Kui Leung, Ciaran Macdonaill, Elmar Jung, Charles Pritchard

Articles

This paper introduces a new development in speech technology and describes its planned application in an EFL context. Special attention is paid to the pedagogical potential of the resultant language tool.

Openmvc: A Non-Proprietary Component-Based Framework For Web Applications, Ronan Barrett, Sarah Jane Delany

Conference papers

No abstract provided.

Virtual Personal Assistants In A Pervasive Computing World, John F. Bradley, Brian R. Duffy, Gregory O'Hare, Alan Martin, Bianca Schoen-Phelan

Conference papers

Computing paradigms are constantly evolving-from mainframe to desktop, and on to ubiquitous computing. With a wide variety of devices, each with varying constraints, it would be quite difficult to develop services that would operate in a uniform manner across all platforms. With this in mind we offer an agent based solution. Agent attributes of autonomy, adaptability and mobility make them highly suitable for use in pervasive computing environments. Agent Chameleons illustrates a framework for Virtual Personal Assistants (VPA) for the information age. This paper briefly outlines some of the technologies and concepts that underpin the functionality of a VPA.

An Agent-Based Approach To Adaptive Navigational Support Within 3d-Environments, Bianca Schoen-Phelan, Gregory O'Hare, Brian Duffy, Alan Martin

Conference papers

his paper investigates mechanisms and approaches to assisting user navigation and exploration within 3-dimensional worlds. Specifically it advocates the deployment of an agentbased approach to dynamic system assistance and intervention. A performance equation is presented in a basic and an extended version, which is used to activate system interventions and to evaluate user performances online and offline. The measure is derived via a light-weight computationally inexpensive masking approach. We describe some navigation experiments and the results of navigational intervention via the damping of the sensitivity of the navigational keys. Interestingly the navigational assistance does not yield improvements in the subjects’ …

Validation Of A Sensitivity Performance Index Test Protocol And Evaluation Of Colour Doppler Sensitivity For A Range Of Ultrasound Scanners, Jacinta Browne, Amanda Watson, Peter Hoskins, Alex Elliott

Articles

The ability to detect flow is the most crucial aspect of an ultrasound (US) system because, if flow cannot be detected, no other aspect of performance matters. The objectives of this study were to validate a Doppler “sensitivity performance index,” a figure of merit, and to determine if it could be used to differentiate colour Doppler sensitivity performance in scanners of varying complexity. The sensitivity performance index was developed to give a combined measure of related aspects of sensitivity, such as the lowest detectable velocity, the vessel size and the penetration depth. The colour Doppler sensitivity was evaluated objectively as …

A Novel Tiq2-Assisted Solar Photocatalytic Batch-Process Disinfection Reactor For The Treatment Of Biological And Chemical Contaminants In Domestic Drinking Water In Developing Countries, E. F. Duffy, F. Al Touati, S. C. Kehoe, O. A. Mcloughlin, L. W. Gill, W. Gernjak, I. Oller, M. I. Maldonado, S. Malato, John Cassidy, R. H. Reed, K. G. Mcguigan

Articles

he technical feasibility and performance of photocatalytic Ti02 coatings in batch-process solar disinfection (SODIS) reactors to improve potability of drinking water in developing countries have been studied. Borosilicate glass and PET plastic SODIS reactors fitted with flexible plastic inserts coated with Ti02 powder were shown to be 2(Jt1o and 25% more effective, respectively, than standard SODIS reactors for the inactivation of E. coli K12. Isopropanol at 100 ppm concentration levels was observed to be completely photodegraded after 24 h continuous exposure to lOG mW/cm2 simulated sunlight in a similar solar photocatalytic disinfector (SPC-DIS) reactor. The technique for p roducing the …

Torsion-Free Weakly Transitive Abelian Groups, Brendan Goldsmith, Lutz Strungmann

Articles

We introduce the notion of weak transitivity for torsion-free abelian groups. A torsion-free abelian group G is called weakly transitive if for any pair of elements x, y ∈ G and endomorphisms ϕ, ψ ∈ End(G) such that xϕ = y, yψ = x, there exists an automorphism of G mapping x onto y. It is shown that every suitable ring can be realized as the endomorphism ring of a weakly transitive torsion-free abelian group, and we characterize up to a number-theoretical property the separable weakly transitive torsion-free abelian groups.

Quasi-Minimal Abelian Groups, Brendan Goldsmith, S. O. Hogain, S. Wallutis

Articles

An abelian group $G$ is said to be quasi-minimal (purely quasi-minimal, directly quasi-minimal) if it is isomorphic to all its subgroups (pure subgroups, direct summands, respectively) of the same cardinality as $G$. Obviously quasi-minimality implies pure quasi-minimality which in turn implies direct quasi-minimality, but we show that neither converse implication holds. We obtain a complete characterisation of quasi-minimal groups. In the purely quasi-minimal case, assuming GCH, a complete characterisation is also established. An independence result is proved for directly quasi-minimal groups.

Riemann Tensor Of The Ambient Universe, The Dilaton, And Newton’S Constant, Rossen Ivanov, Emil Prodanov

Articles

We investigate a four-dimensional world, embedded into a five-dimensional spacetime, and find the five-dimensional Riemann tensor via generalisation of the Gauss (--Codacci) equations. We then derive the generalised equations of the four-dimensional world and also show that the square of the dilaton field is equal to the Newton's constant. We find plausable constant and non-constant solutions for the dilaton. Comment: 5 pages, revtex

The Spectral Function For Sturm-Liouville Problems Where The Potential Is Of Wigner-Von Neumann Type Or Slowly Decaying, Daphne Gilbert, B.J. Harris, S.M. Riehl

Articles

We consider the linear, second-order, differential equation (∗) with the boundary condition (∗∗)

We suppose that q(x) is real-valued, continuously differentiable and that q(x)→0 as x→∞ with q∉L1[0,∞). Our main object of study is the spectral function ρα(λ) associated with () and (). We derive a series expansion for this function, valid for λ⩾Λ0 where Λ0 is computable and establish a Λ1, also computable, such that () and () with α=0, have no points of spectral concentration for λ⩾Λ1. We illustrate our results with examples. In particular we consider the case of the Wigner–von Neumann potential.

High-Speed Electronic Speckle Pattern Interferometry, Carol Armstrong

Masters

Electronic Speckle Pattern Interferometry (ESPI) is used to measure surface displacements. Phase shifting can be used to obtain a fringe pattern which depicts the phase at every point in an image. Previous studies have used algorithms such as the 4-bucket algorithm to obtain phase maps of objects. After the object is displaced a second phase map is obtained in the same way and by correlation the phase difference due to the displacement can be determined. When the object is in rapid continuous motion these algorithms cannot be used. Towards this end a 5-frame algorithm was written, in which the calibrated …

Studies In Cardiac Defribrillation, Eamonn Mckenna

Masters

Cardiac disease resulting in cardiac arrest is one of the most common fatal diseases in the developed world. Defibrillation is the medical procedure used to correct the irregular cardiac rhythm (ventricular fibrillation (VF)) which is very often detected in patients suffering cardiac arrest. In the work reported in this thesis, two aspects of the defibrillation of patients in VF were examined. The first area of investigation concentrated on the use of multiple defibrillation electrodes to be used during closed chest (transthoracic) defibrillation. This study was carried out in a saline bath and centred on “focusing” electric fields from perimeter electrodes …