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Articles 2191 - 2220 of 2383
Full-Text Articles in Physical Sciences and Mathematics
Intentional Embodied Agents, Alan Martin, Gregory M.P. O'Hare, Brian R. Duffy, John F. Bradley, Bianca Schoen-Phelan
Intentional Embodied Agents, Alan Martin, Gregory M.P. O'Hare, Brian R. Duffy, John F. Bradley, Bianca Schoen-Phelan
Conference papers
The notion of embodiment within a virtual environment and an intelligent agent could be intimately linked, in order to form a single Agent Chameleon. This paper presents an architecture for achieving this, while allowing agents freedom to chose an embodiment suitable to the task at hand..
The Amphere Algorithm: Area Masking With The Performance Equation, Bianca Schoen-Phelan, Gregory O'Hare, Brian Duffy, Alan Martin, John Bradley
The Amphere Algorithm: Area Masking With The Performance Equation, Bianca Schoen-Phelan, Gregory O'Hare, Brian Duffy, Alan Martin, John Bradley
Conference papers
This paper is concerned with the employment of an autonomous and intelligent agent within the context of a 3-dimensional virtual environment. As the agent is immersed within the virtual environment, it empowers the 3D world with mechanisms to adjust itself to the specific needs of its user. Therefore, the agent serves as a middle layer between user and the environment. The 3-dimensional environment thus evolved into an intelligent user interface. We track user’s motion within this environment and present an equation upon which the agent classifies the user’s performance. Based upon this performance value, the agent autonomously determines if the …
Bi-Directional Ontology Versioning Bov, Siyang Zhao, Brendan Tierney
Bi-Directional Ontology Versioning Bov, Siyang Zhao, Brendan Tierney
Conference papers
his paper defines a new type of ontology versioning: Bi-directional Ontology Versioning: BOV. BOV provides bi-directional mappings and transformations between concepts in two ontology versions. BOV is identified by two levels mapping processes: linguistic mapping and structural mapping. BOV can satisfy the requirement of mapping in distributed environment.
Generating Estimates Of Classification Confidence For A Case-Based Spam Filter, Sarah Jane Delany, Padraig Cunningham, Donal Coyle, Anton Zamolotskikh
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 …
Photocontrol Of Upper And Lower Rim Complexation Of Neutral And Cationic Species By P-Tert-Butylcalix[4]Arene Tetraethyl Ester, Mary Deasy, Bernadette Creaven, Brian A. Murray, Catherine Mckenna, Darren Tobin
Photocontrol Of Upper And Lower Rim Complexation Of Neutral And Cationic Species By P-Tert-Butylcalix[4]Arene Tetraethyl Ester, Mary Deasy, Bernadette Creaven, Brian A. Murray, Catherine Mckenna, Darren Tobin
Articles
A number of sodium salt complexes of p-tert-butylcalix[4]arene tetraethyl ester, 1, were isolated both with and without upper-rim encapsulated solvent. Selective decomplexation of lower rim bound sodium cations and upper rim encapsulated solvent molecules could be successfully achieved using low pressure light sources. Oxidation of the counter anion at the lower rim of p-tert-butylcalix[4]arene tetraethyl ester triggered both the upper and lower rim decomplexation process. The extent of decomplexation at both rims is controlled both by the nature of the counter-anionic species at the lower rim and by the fate of the photoproducts generated. The calixarene host …
Evaluating The Use Of In Vitro Bioassays For The Ecotoxicological Assessment Of Irish Estuarine Sediments, Sharon Ni Shuilleabhain
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 …
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 …
Stark Width And Shift Of The Neutral Argon 425.9 Nm Spectral Line, Vladimir Milosavljevic, Vida Zigman, Stevan Djenize
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 (Wt), i.e. We and Wi, as well as to the total Stark shift (dt), i.e. …
On The Dressing Method For The Generalised Zakharov-Shabat System, Rossen Ivanov
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
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
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
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
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
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
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
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
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 …
The Exterior Orientation Of Aerial Imagery Using Existing Orthoimagery And Terrain Models:A Performance Test, Finnian O'Cionnaith
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 …
Torsion-Free Weakly Transitive Abelian Groups, Brendan Goldsmith, Lutz Strungmann
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.
Electronic Speckle Pattern Shearing Interferometry Using Photopolymer Diffractive Optical Elements For Vibration Measurements, Emilia Mihaylova, Izabela Naydenova, Suzanne Martin, Vincent Toal
Electronic Speckle Pattern Shearing Interferometry Using Photopolymer Diffractive Optical Elements For Vibration Measurements, Emilia Mihaylova, Izabela Naydenova, Suzanne Martin, Vincent Toal
Conference Papers
Electronic speckle pattern shearing interferometry (ESPSI) is superior to Electronic speckle pattern interferometry (ESPI) when strain distribution, arising from object deformation or vibration, need to be measured. This is because shearography provides data directly related to the spatial derivatives of the displacement. Further development of ESPSI systems could be beneficial for wider application to the measurement of mechanical characteristics of vibrating objects. Two electronic speckle pattern shearing interferometers (ESPSI) suitable for vibration measurements are presented. In both ESPSI systems photopolymer holographic gratings are used to shear the images and to control the size of the shear. The holographic gratings are …
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
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 …
Empowering Agents Within Virtual Environments, Alan Martin, Brian Duffy, Gregory O'Hare, Bianca Schoen-Phelan, John Bradley
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 …
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
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.
A University Online Portal For Enterprise Learning Communities, Marco Neumann, Ciaran Mcdonnell, Deirdre Hogan, Carol Reinsford, Stefan Decker
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.
On The Cotorsion Images Of The Baer-Specker Group, Brendan Goldsmith, T. Kelly, S, Wallutis
On The Cotorsion Images Of The Baer-Specker Group, Brendan Goldsmith, T. Kelly, S, Wallutis
Articles
No abstract available
Quasi-Minimal Abelian Groups, Brendan Goldsmith, S. O. Hogain, S. Wallutis
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.
On The Empirical Balanced Truncation For Nonlinear Systems, Marissa Condon, Rossen Ivanov
On The Empirical Balanced Truncation For Nonlinear Systems, Marissa Condon, Rossen Ivanov
Articles
Novel constructions of empirical controllability and observability gramians for nonlinear systems for subsequent use in a balanced truncation style of model reduction are proposed. The new gramians are based on a generalisation of the fundamental solution for a Linear Time-Varying system. Relationships between the given gramians for nonlinear systems and the standard gramians for both Linear Time-Invariant and Linear Time-Varying systems are established as well as relationships to prior constructions proposed for empirical gramians. Application of the new gramians is illustrated through a sample test-system.
Riemann Tensor Of The Ambient Universe, The Dilaton, And Newton’S Constant, Rossen Ivanov, Emil Prodanov
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
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.
Non Linear Electronic And Optical Processes In Fullerene Thin Films, Siobhan Phelan
Non Linear Electronic And Optical Processes In Fullerene Thin Films, Siobhan Phelan
Masters
In this study the current voltage characteristics of C60 thin film sandwich structures fabricated by vacuum deposition on indium tin oxide (ITO) with an aluminium top electrode are presented and discussed. A strongly non-linear behaviour and a sharp increase in the device conductivity was observed at relatively low voltages, at both room and low temperatures (30K). At room temperature the system is seen to collapse. In situ Raman measurements indicate that the collapse is the result of a solid state reduction of the fullerene thin film to a polymeric state. The high conductivity state was seen to be stable at …