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Articles 1801 - 1830 of 2383

Full-Text Articles in Physical Sciences and Mathematics

Exploring The Frontier Of Uncertainty Space, Rong Hu, Patrick Lindstrom, Sarah Jane Delany, Brian Mac Namee Jan 2010

Exploring The Frontier Of Uncertainty Space, Rong Hu, Patrick Lindstrom, Sarah Jane Delany, Brian Mac Namee

Conference papers

We aim to investigate methods balancing exploitation with exploration in active learning to improve the performance of uncertainty sampling. Two exploration guided sampling methods are compared to uncertainty sampling on various real-life datasets from the 2010 Active Learning Challenge. Our initial experiments seems to indicate that combining exploration with uncertainty sampling improves performance on certain datasets but not all.

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A Generalized Nonlinear Model For The Evolution Of Low Frequency Freak Waves, Jonathan Blackledge Jan 2010

A Generalized Nonlinear Model For The Evolution Of Low Frequency Freak Waves, Jonathan Blackledge

Articles

This paper presents a generalized model for simulating wavefields associated with the sea surface. This includes the case when `freak waves' may occur through an effect compounded in the nonlinear (cubic) Schrodinger equation. After providing brief introductions to linear sea wave models, `freak waves' and the linear and nonlinear Schrodinger equations, we present a unified model that provides for a piecewise continuous transition from a linear to a nonlinear state. This is based on introducing a fractional time derivative to develop a fractional nonlinear partial differential equation with a stochastic source function. In order to explore the characteristics of this …

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Fractional Anisotropic Diffusion For Noise Reduction In Magnetic Resonance Images, Jonathan Blackledge, Matthew Blackledge Jan 2010

Fractional Anisotropic Diffusion For Noise Reduction In Magnetic Resonance Images, Jonathan Blackledge, Matthew Blackledge

Articles

We extend the method of anisotropic diffusion for noise reduction in digital images to the case when the diffusion processes are non-Gaussian and Levy distributed. This yields a fractional diffusion equation characterised by the Levy index. A solution to this equation is considered and a numerical algorithm developed. The algorithm is then applied as a case study to the problem of reducing noise in magnetic resonance imaging. The focus of this study is on diffusion weighted images which have low signal-to-noise ratios.

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Serine- And Arginine-Rich Proteins 55 And 75 (Srp55 And Srp75) Induce Production Of Hiv-1 Vpr Mrna By Inhibiting The 5′-Splice Site Of Exon 3, Anna Tranell, Eva Maria Fenyö, Stefan Schwartz Jan 2010

Serine- And Arginine-Rich Proteins 55 And 75 (Srp55 And Srp75) Induce Production Of Hiv-1 Vpr Mrna By Inhibiting The 5′-Splice Site Of Exon 3, Anna Tranell, Eva Maria Fenyö, Stefan Schwartz

Articles

HIV-1 non-coding exon 3 can either be spliced to exons 4, 4a, 4b, 4c, and 5 to generate tat, rev, and nef mRNAs or remain unspliced to produce the 13a7 vpr mRNA. Here we show that serine- and arginine-rich proteins 55 and 75 (SRp55 and SRp75) inhibit splicing from the 5′-splice site of exon 3 thereby causing an accumulation of the partially unspliced 13a7 vpr mRNA. In contrast, serine- and arginine-rich protein 40 (SRp40) induces splicing from exon 3 to exon 4, thereby promoting the production of the 1347 tat mRNA. We demonstrate that SRp55 stimulates vpr mRNA production by …

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Spectroscopic And Chemometric Approaches To Radiobiological Analyses, Aidan Meade, Hugh Byrne, Fiona Lyng Jan 2010

Spectroscopic And Chemometric Approaches To Radiobiological Analyses, Aidan Meade, Hugh Byrne, Fiona Lyng

Articles

No abstract provided.

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Functional And Pathological Analysis Of Biological Systems Using Vibrational Spectroscopy With Chemometric And Heuristic Approaches, Aidan Meade, Colin Clarke, Franck Bonnier, Kelvin W. Poon, Amaya Garcia, Peter Knief, Kamila Ostrowska, Lorenzo Salford, Haq Nawaz, Fiona Lyng, Hugh Byrne Jan 2010

Functional And Pathological Analysis Of Biological Systems Using Vibrational Spectroscopy With Chemometric And Heuristic Approaches, Aidan Meade, Colin Clarke, Franck Bonnier, Kelvin W. Poon, Amaya Garcia, Peter Knief, Kamila Ostrowska, Lorenzo Salford, Haq Nawaz, Fiona Lyng, Hugh Byrne

Articles

Vibrational spectroscopy (Raman and FTIR microspectroscopy) is an attractive modality for the analysis of biological samples since it provides a complete non-invasive acquisition of the biochemical fingerprint of the sample. Studies in our laboratory have applied vibrational spectroscopy to the analysis of biological function in response to external agents (chemotherapeutic drugs, ionising radiation, nanoparticles), together with studies of the pathology of tissue (skin and cervix) in health and disease. Genetic algorithms have been used to optimize spectral treatments in tandem with the analysis of the data (using generalized regression neural networks (GRNN), artificial neural networks (ANN), partial least squares modelling …

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Studies Of Chemical Fixation Effects In Human Cell Lines Using Raman Microspectroscopy, Aidan Meade, Colin Clarke, Florence Draux, Ganesh Sockalingum, Michel Manfait, Fiona Lyng, Hugh Byrne Jan 2010

Studies Of Chemical Fixation Effects In Human Cell Lines Using Raman Microspectroscopy, Aidan Meade, Colin Clarke, Florence Draux, Ganesh Sockalingum, Michel Manfait, Fiona Lyng, Hugh Byrne

Articles

The in vitro study of cellular species using Raman spectroscopy has proven a powerful non-invasive modality for the analysis of cell constituents and processes. This work uses micro-Raman spectroscopy to study the chemical fixation mechanism in three human cell lines (normal skin, normal bronchial epithelium, and lung adenocarcinoma) employing fixatives that preferentially preserve proteins (formalin), and nucleic acids (Carnoy’s fixative and methanol–acetic acid). Spectral differences between the mean live cell spectra and fixed cell spectra together with principal components analysis (PCA), and clustering techniques were used to analyse and interpret the spectral changes. The results indicate that fixation in formalin …

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Photopolymerizable Nanocomposites For Holographic Recording And Sensor Application, Elsa Leite, Izabela Naydenova, Svetlana Mintova, Louis Leclercq, Vincent Toal Jan 2010

Photopolymerizable Nanocomposites For Holographic Recording And Sensor Application, Elsa Leite, Izabela Naydenova, Svetlana Mintova, Louis Leclercq, Vincent Toal

Articles

Novel nanocomposites consisting of a water soluble acrylamide–based photopolymer and colloidal zeolite nanoparticles of zeolite Beta and zeolite A were prepared. The interactions between the photopolymer components and zeolite nanoparticles in the photopolymerizable nanocomposites were characterized for the first time by 13C NMR and Visible spectroscopy. It was found that the zeolite Beta nanoparticles (up to 5% wt.) behave as a non-inert additive, resulting in an effective increase in layer thickness that causes doubling of the diffraction efficiency of the nanocomposite in comparison to that of the undoped photopolymer. On the other hand, the nanocomposite containing zeolite A nanoparticles showed …

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Optical Properties Of Photopolymer Layers Doped With Aluminophosphate Nanocrystals, Elsa Leite, Tzvetanka Babeva, E Ng, Vincent Toal, Svetlana Mintova, Izabela Naydenova Jan 2010

Optical Properties Of Photopolymer Layers Doped With Aluminophosphate Nanocrystals, Elsa Leite, Tzvetanka Babeva, E Ng, Vincent Toal, Svetlana Mintova, Izabela Naydenova

Articles

The optical properties of photopolymer layers consisting of an acrylamide–based matrix and microporous aluminophosphate nanocrystals of AEI- type are investigated. The compatibility of the photopolymer doped with the nanoparticles is studied. The surface and volume properties of the layers with different levels of doping with microporous nanocrystals are characterized. The effective refractive indices and absorption coefficients of the doped photopolymer layers are determined and used to calculate the refractive index and porosity of pure AEI nanoparticles used as dopants. Volume transmission gratings were recorded in the doped photopolymer layers at different spatial frequencies. By spatial monitoring of the characteristic Raman …

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Two-Way Diffusion Model For Short Exposure Holographic Grating Formation In Acrylamide-Based Photopolymer, Tzvetanka Babeva, Izabela Naydenova, Dana Mackey, Suzanne Martin, Vincent Toal Jan 2010

Two-Way Diffusion Model For Short Exposure Holographic Grating Formation In Acrylamide-Based Photopolymer, Tzvetanka Babeva, Izabela Naydenova, Dana Mackey, Suzanne Martin, Vincent Toal

Articles

A theoretical model for formation of a short exposure holographic grating is presented. The model accounts for both monomer and polymer diffusion and distinguishes between short polymer chains capable of diffusing and long polymer chains that are immobile. It is shown that the experimentally observed decrease of diffraction efficiency at higher spatial frequency can be predicted by assuming diffusion of short-chain polymers away from the bright fringes. The time evolution of the refractive index modulation after short exposure is calculated and compared with experimental results. The effects of diffusion coefficients, polymerization rates, intensity and spatial frequency of recording on the …

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Optimisation Of An Acrylamide-Based Photopolymer System For Holographic Inscription Of Surface Patterns With Sub-Micron Resolution, Kevin Trainer, Kevin Wearen, Dimana Nazarova, Izabela Naydenova, Vincent Toal Jan 2010

Optimisation Of An Acrylamide-Based Photopolymer System For Holographic Inscription Of Surface Patterns With Sub-Micron Resolution, Kevin Trainer, Kevin Wearen, Dimana Nazarova, Izabela Naydenova, Vincent Toal

Articles

We describe the optimisation of the holographic patterning of sub-micrometer surface relief structures in an acrylamide-based photopolymer. A substantial improvement in the photoinduced surface relief resolution was achieved by altering the photopolymer chemical composition and by introducing a single step post recording thermal treatment of the layers. It was observed that, by optimisation of the chemical composition of the photopolymer layers, the maximum achievable spatial frequency increases from 200 l/mm to 550 l/mm. The improvement of the surface relief amplitude by alteration of the chemical composition is limited due to the fact that both decrease of the plasticiser and increase …

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Study Of The Photoinduced Surface Relief Modulation In Photopolymers Caused By Illumination With A Gaussian Beam Of Light, Tzvetanka Babeva, Dana Mackey, Suzanne Martin, Izabela Naydenova, Vincent Toal Jan 2010

Study Of The Photoinduced Surface Relief Modulation In Photopolymers Caused By Illumination With A Gaussian Beam Of Light, Tzvetanka Babeva, Dana Mackey, Suzanne Martin, Izabela Naydenova, Vincent Toal

Articles

The formation of surface relief profile in photopolymerisable systems when illuminated with a focused beam of light is simulated numerically using a two-way diffusion model that takes account both for monomer and short polymer chains diffusion. The concentration and spatial distribution dynamics of monomer and short and long polymer chains are calculated. The surface profile is obtained from calculated components concentrations considering different densities of monomer and polymer. The influence of the illumination time, intensity and spot diameter on the surface profiles dynamics is discussed. A good agreement between the calculated and the experimentally measured profiles is observed thus demonstrating …

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A Diffusion Model For Spatially Dependent Photopolymerization, Dana Mackey, Tzvetanka Babeva, Izabela Naydenova, Vincent Toal Jan 2010

A Diffusion Model For Spatially Dependent Photopolymerization, Dana Mackey, Tzvetanka Babeva, Izabela Naydenova, Vincent Toal

Articles

Photopolymers represent an attractive class of optical recording materials due to properties such as high refractive index modulation, dry film processing, long shelf life, etc. Applications include holographically based devices for optical storage disks, optical interconnections, optical memories and filters. This paper will address the dynamics of short-exposure holographic grating formation; a new mathematical model is proposed with the aim of understanding the experimental observations of low diffraction efficiency in high spatial frequency gratings.

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Vibration Phase Measurements Using Holographic Optical Elements, Viswanath Bavigadda, Raghavendra Jallapuram, Vincent Toal, Emilia Mihaylova Jan 2010

Vibration Phase Measurements Using Holographic Optical Elements, Viswanath Bavigadda, Raghavendra Jallapuram, Vincent Toal, Emilia Mihaylova

Articles

The application of an out-of-plane sensitive electronic speckle pattern interferometer (ESPI) using holographic optical element (HOE) to vibration amplitude and phase mapping is reported. The novelty of the proposed system is the use of a speckle reference wave stored in a reflection holographic optical element (HOE). The incorporation of a HOE minimizes the alignment difficulties. The HOE based ESPI system is compact containing only a diode laser, HOE and a digital CMOS camera. The measurement technique is a combination of time averaged ESPI and reference beam phase modulation in an unbalanced interferometer. The reference beam phase modulation is implemented by …

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On The Applications Of Deterministic Chaos For Encrypting Data On The Cloud, Jonathan Blackledge, Nikolai Ptitsyn Jan 2010

On The Applications Of Deterministic Chaos For Encrypting Data On The Cloud, Jonathan Blackledge, Nikolai Ptitsyn

Conference papers

Cloud computing is expected to grow considerably in the future because it has so many advantages with regard to sale and cost, change management, next generation architectures, choice and agility. However, one of the principal concerns for users of the Cloud is lack of control and above all, data security. This paper considers an approach to encrypting information before it is ‘place’ on the Cloud where each user has access to their own encryption algorithm, an algorithm that is based on a set of Iterative Function Systems that outputs a chaotic number stream, designed to produce a cryptographically secure cipher. …

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Economic Risk Assessment Using The Fractal Market Hypothesis, Jonathan Blackledge, Marek Rebow Jan 2010

Economic Risk Assessment Using The Fractal Market Hypothesis, Jonathan Blackledge, Marek Rebow

Conference papers

This paper considers the Fractal Market Hypothesi (FMH) for assessing the risk(s) in developing a financial portfolio based on data that is available through the Internet from an increasing number of sources. Most financial risk management systems are still based on the Efficient Market Hypothesis which often fails due to the inaccuracies of the statistical models that underpin the hypothesis, in particular, that financial data are based on stationary Gaussian processes. The FMH considered in this paper assumes that financial data are non-stationary and statistically self-affine so that a risk analysis can, in principal, be applied at any time scale …

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Authentication Of Biometric Features Using Texture Coding For Id Cards, Jonathan Blackledge, Eugene Coyle Jan 2010

Authentication Of Biometric Features Using Texture Coding For Id Cards, Jonathan Blackledge, Eugene Coyle

Conference papers

The use of image based information exchange has grown rapidly over the years in terms of both e-to-e image storage and transmission and in terms of maintaining paper documents in electronic form. Further, with the dramatic improvements in the quality of COTS (Commercial-Off-The-Shelf) printing and scanning devices, the ability to counterfeit electronic and printed documents has become a widespread problem. Consequently, there has been an increasing demand to develop digital watermarking techniques which can be applied to both electronic and printed images (and documents) that can be authenticated, prevent unauthorized copying of their content and, in the case of printed …

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Encryption Using Deterministic Chaos, Jonathan Blackledge, Nikolai Ptitsyn Jan 2010

Encryption Using Deterministic Chaos, Jonathan Blackledge, Nikolai Ptitsyn

Articles

The concepts of randomness, unpredictability, complexity and entropy form the basis of modern cryptography and a cryptosystem can be interpreted as the design of a key-dependent bijective transformation that is unpredictable to an observer for a given computational resource. For any cryptosystem, including a Pseudo-Random Number Generator (PRNG), encryption algorithm or a key exchange scheme, for example, a cryptanalyst has access to the time series of a dynamic system and knows the PRNG function (the algorithm that is assumed to be based on some iterative process) which is taken to be in the public domain by virtue of the Kerchhoff-Shannon …

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An Optical Machine Vision System For Applications In Cytopathology, Jonathan Blackledge, Dmitry Dubovitskiy Jan 2010

An Optical Machine Vision System For Applications In Cytopathology, Jonathan Blackledge, Dmitry Dubovitskiy

Articles

This paper discusses a new approach to the processes of object detection, recognition and classification in a digital image focusing on problem in Cytopathology. A unique self learning procedure is presented in order to incorporate expert knowledge. The classification method is based on the application of a set of features which includes fractal parameters such as the Lacunarity and Fourier dimension. Thus, the approach includes the characterisation of an object in terms of its fractal properties and texture characteristics. The principal issues associated with object recognition are presented which include the basic model and segmentation algorithms. The self-learning procedure for …

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Development Of A Panchromatic Acrylamide Based Photopolymer For Multicolour Reflection Holography, Chakrapani Meka, Raghavendra Jallapuram, Izabela Naydenova, Suzanne Martin, Vincent Toal Jan 2010

Development Of A Panchromatic Acrylamide Based Photopolymer For Multicolour Reflection Holography, Chakrapani Meka, Raghavendra Jallapuram, Izabela Naydenova, Suzanne Martin, Vincent Toal

Articles

The development of a panchromatic acrylamide based photopolymer (ABP) for holographic recording application is presented. The scattering of the recording medium was characterised by measuring the Bidirectional Scattering Distribution Function (BSDF). The dynamic range in reflection mode of recording was evaluated by measuring the diffraction efficiencies of the holographic gratings recorded individually at 633nm, 532nm, and 473nm wavelengths at spatial frequencies of 4200 l/mm, 5000 l/mm and 5700 l/mm respectively. Spectral characterisation of the reflection gratings recorded using a combined single RGB beam was carried out and the reconstructed wavelengths were monitored and compared with the recording wavelengths. The recorded …

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Design And Fabrication Of Holographic Optical Elements For Applications In Electronic Speckle Pattern Interferometry And Laser Doppler Vibrometry, Viswanath Bavigadda, Emilia Mihaylova, Raghavendra Jallapuram, Vincent Toal Jan 2010

Design And Fabrication Of Holographic Optical Elements For Applications In Electronic Speckle Pattern Interferometry And Laser Doppler Vibrometry, Viswanath Bavigadda, Emilia Mihaylova, Raghavendra Jallapuram, Vincent Toal

Conference Papers

An important area of application of holographic optical elements (HOEs) is in optical and electronic speckle pattern interferometry. The design, fabrication and characterization of holographic optical elements (HOEs) for electronic speckle pattern interferometry are presented. Reflection HOEs (RHOEs) were fabricated for use in electronic speckle pattern interferometers (ESPI) and laser Doppler vibrometers (LDV). The HOE-based interferometer is sensitive to out-of-plane displacements only. The results obtained are promising for future applications of the system for modal analysis.

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A Systematic Study Of The Dispersion Of Swnts In Organic Solvents, Qiaohuan Cheng, Sourabhi Debnath, Luke O'Neill, Theresa Hedderman, Elizabeth Gregan, Hugh Byrne Jan 2010

A Systematic Study Of The Dispersion Of Swnts In Organic Solvents, Qiaohuan Cheng, Sourabhi Debnath, Luke O'Neill, Theresa Hedderman, Elizabeth Gregan, Hugh Byrne

Articles

Dispersions of as-produced HiPco single-walled carbon nanotubes (SWNTs) in a series of organic solvents were prepared by dilution with the aid of tip sonication. Mild centrifugation (~ 945 g) was carried out to remove large bundles. Atomic force microscopy (AFM) studies revealed that the bundle size decreased as the dispersion was diluted. By measuring the UV-vis-NIR absorption before and after centrifugation as a function of the concentration, the dispersion limit of SWNTs in each solvent can be determined. Correlations between the dispersion limit and solvent solubility parameters, including the Hildebrand solubility parameter and three dimensional Hansen solubility parameters, are explored, …

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Electrochemical Characterisation Of Poly Arylene Vinylenes, Jonathan Moghal, Patrick Lynch, Mary Mcnamara, Hugh Byrne, Gordon Chambers Jan 2010

Electrochemical Characterisation Of Poly Arylene Vinylenes, Jonathan Moghal, Patrick Lynch, Mary Mcnamara, Hugh Byrne, Gordon Chambers

Articles

The electrochemical properties of a newly synthesised set of PPV derivatives were measured by cyclic voltammetry. A new octyloxy substituted PPV derivative was first synthesised (POPV). The structure of the POPV is varied systematically by the replacement of the phenyl units by naphthyl and anthryl units and the effect of these variations on the electrochemical properties is explored. The HOMO–LOMO levels of the polymers were determined from the onset potentials for the p-doping and n-doping scans. From this the electrochemical bandgap for each of the polymers was calculated. The systematic change in the structure of the POPV results in a …

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The Extent Of Clientelism In Irish Politics: Evidence From Classifying Dáil Questions On A Local-National Dimension, Sarah Jane Delany, Richard Sinnott, Niall O'Reilly Jan 2010

The Extent Of Clientelism In Irish Politics: Evidence From Classifying Dáil Questions On A Local-National Dimension, Sarah Jane Delany, Richard Sinnott, Niall O'Reilly

Conference papers

The availability of the full text of Irish parliamentary questions offers opportunities for using machine learning techniques to examine the currently much discussed role of elected representatives (TDs) in the Irish parliamentary system. Bluntly, are TDs mainly national legislators or “constituency messenger boys”? This paper presents an initial investigation into the use of automated text classification techniques to categorise parliamentary questions from 1922 up to 2008 as national or local. The approach uses a bag of words representation, standard feature reduction methods and an SVM classifier. Initial results show there is very little evidence in the corpus of parliamentary questions …

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Quantitative Modelling Approaches For Ascorbic Acid Degradation And Non-Enzymatic Browning Of Orange Juice During Ultrasound Processing, Vasilis Valdramidis, Patrick J. Cullen, Brijesh Tiwari, Colm O’Donnell Jan 2010

Quantitative Modelling Approaches For Ascorbic Acid Degradation And Non-Enzymatic Browning Of Orange Juice During Ultrasound Processing, Vasilis Valdramidis, Patrick J. Cullen, Brijesh Tiwari, Colm O’Donnell

Articles

The objective of this study was to develop a deterministic modelling approach for non-enzymatic browning (NEB) and ascorbic acid (AA) degradation in orange juice during ultrasound processing. Freshly squeezed orange juice was sonicated using a 1,500 W ultrasonic processor at a constant frequency of 20 kHz and processing variables of amplitude level (24.4 – 61.0 μm), temperature (5 – 30 oC) and time (0 – 10 min). The rate constants of the NEB and AA were estimated by a primary model (zero and first order) while their relationship with respect to the processing factors was tested for a number of …

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Rapid Microwave Synthesis Of Mesoporous Tio2 For Electrochromic Displays, Suresh Pillai, Declan Mccormack, Pradeepan Periyat, Nigel Leyland, David Corr, John Colreavy Jan 2010

Rapid Microwave Synthesis Of Mesoporous Tio2 For Electrochromic Displays, Suresh Pillai, Declan Mccormack, Pradeepan Periyat, Nigel Leyland, David Corr, John Colreavy

Articles

No abstract provided.

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Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy Jan 2010

Corrosion Protection Of Aa 2024-T3 Aluminium Alloys Using 3, 4-Diaminobenzoic Acid Chelated Zirconium-Silane Hybrid Sol-Gels, P.C. Rajath Varma, John Colreavy, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, Brendan Duffy

Articles

Organic-inorganic polymers formed by hydrolysis/condensation reactions of alkoxide precursors, such as organically modified silanes (Ormosils) have found applications as electronic, optical and protective coatings. Such coatings possess important characteristics such as chemical stability, physical strength and scratch resistance. Further performance improvement is achieved through the incorporation of zirconium and titanium based nanoparticles, also formed through the sol-gel process. However due to the inherent difference in the reactivity of the precursors, the hydrolysis of each precursor must be carried out separately before being combined for final condensation. Zirconium precursors are commonly chelated using acetic acid or acetyl acetonate prior to hydrolysis, …

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Single Step Morphology-Controlled Synthesis Of Silver Nanoparticles, Vinodkumar Etacheri, Reenamole Georgekutty, Michael Seery, Suresh Pillai Jan 2010

Single Step Morphology-Controlled Synthesis Of Silver Nanoparticles, Vinodkumar Etacheri, Reenamole Georgekutty, Michael Seery, Suresh Pillai

Articles

Silver nanoparticles having different size and plasmon resonances were synthesized through a single step aqueous based method. The current procedure was based on the reduction of silver ions by ascorbic acid in the presence of sodiumborohydride and trisodium citrate. Triangular colloidal nanoparticles having different plasmon resonances (and hence different size and colours) were synthesized by varying only the concentration of ascorbic acid. These nanoparticles were found to be stable without using any surfactants or polymers. This study revealed a strong correlation between particle growth and concentration of constituent chemicals. Crystallinity and phase purity of the silver samples were investigated through …

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Cognitive Effort For Multi Agent Systems, Luca Longo Jan 2010

Cognitive Effort For Multi Agent Systems, Luca Longo

Conference papers

Cognitive Effort is a multi-faceted phenomenon that has suffered from an imperfect understanding, an informal use in everyday life and numerous definitions. This paper attempts to clarify the concept, along with some of the main influencing factors, by presenting a possible heuristic formalism intended to be implemented as a computational concept, and therefore be embedded in an artificial agent capable of cognitive effort-based decision support. Its applicability in the domain of Artificial Intelligence and Multi-Agent Systems is discussed. The technical challenge of this contribution is to start an active discussion towards the formalisation of Cognitive Effort and its application in …

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Scalable Multi-Modal Avatar Interface For Multi-User Environments, Brian Mac Namee, Mark Dunne, John D. Kelleher Jan 2010

Scalable Multi-Modal Avatar Interface For Multi-User Environments, Brian Mac Namee, Mark Dunne, John D. Kelleher

Conference papers

This research outlines an Intelligent Virtual Agent (IVA) interface, where multiple users will be able to interact with 3D avatars. This will take place in a distributed multi-modal environ- ment where the LOK8 Avatar System (AS) will need to locate it’s users from a crowd, using face tracking and novel 3D animation techniques.

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