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On Adjoint Entropy Of Abelian Groups, Brendan Goldsmith, Ketao Gong Jan 2011

On Adjoint Entropy Of Abelian Groups, Brendan Goldsmith, Ketao Gong

Articles

The theory of endomorphism rings of algebraic structures allows, in a natural way, a systematic approach based on the notion of entropy borrowed from dynamical systems. In the present work we introduce a \lq dual\rq \ notion based upon the replacement of the finite groups used in the definition of algebraic entropy, by subgroups of finite index. The basic properties of this new entropy are established and a connection to Hopfian groups is investigated.


Holomorphic Liftings From Infinite Dimensional Spaces, Sean Dineen, Milena Venkova Jan 2011

Holomorphic Liftings From Infinite Dimensional Spaces, Sean Dineen, Milena Venkova

Articles

We obtain a number of positive solutions to a holomorphic lifting problem on a domain in a locally convex space.


Why Is An Einstein Ring Blue?, Jonathan Blackledge Jan 2011

Why Is An Einstein Ring Blue?, Jonathan Blackledge

Articles

Albert Einstein predicted the existence of `Einstein rings' as a consequence of his general theory of relativity. The phenomenon is a direct result of the idea that if a mass warps space-time then light (and other electromagnetic waves) will be `lensed' by the strong gravitational field produced by a large cosmological body such as a galaxy. Since 1998, when the first complete Einstein ring was observed, many more complete or partially complete Einstein rings have been observed in the radio and infrared spectra, for example, and by the Hubble Space Telescope in the optical spectrum. However, in the latter case, …


A Generalized Nonlinear Model For The Evolution Of Low Frequency Freak Waves, Jonathan Blackledge Jan 2011

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

Articles

This paper presents a generalized model for simulating wave fields 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 …


Cryptography Using Steganography: New Algorithms And Applications, Jonathan Blackledge Jan 2011

Cryptography Using Steganography: New Algorithms And Applications, Jonathan Blackledge

Articles

Developing methods for ensuring the secure exchange of information is one of the oldest occupations in history. With the revolution in Information Technology, the need for securing information and the variety of methods that have been developed to do it has expanded rapidly. Much of the technology that forms the basis for many of the techniques used today was originally conceived for use in military communications and has since found a place in a wide range of industrial and commercial sectors. This has led to the development of certain industry standards that are compounded in specific data processing algorithms together …


Application Of Stochastic Diffusion For Hiding High Fidelity Encrypted Images, Jonathan Blackledge, Abdulrahman Al-Rawi Jan 2011

Application Of Stochastic Diffusion For Hiding High Fidelity Encrypted Images, Jonathan Blackledge, Abdulrahman Al-Rawi

Articles

Cryptography coupled with information hiding has received increased attention in recent years and has become a major research theme because of the importance of protecting encrypted information in any Electronic Data Interchange system in a way that is both discrete and covert. One of the essential limitations in any cryptography system is that the encrypted data provides an indication on its importance which arouses suspicion and makes it vulnerable to attack. Information hiding of Steganography provides a potential solution to this issue by making the data imperceptible, the security of the hidden information being a threat only if its existence …


Non-Gaussian Analysis Of Wind Velocity Data For The Determination Of Power Quality Control, Jonathan Blackledge, Eugene Coyle, Derek Kearney Jan 2011

Non-Gaussian Analysis Of Wind Velocity Data For The Determination Of Power Quality Control, Jonathan Blackledge, Eugene Coyle, Derek Kearney

Articles

The quality of power (i.e. the sustainable power output as a function time) of any wind dependent energy converter (including wind turbines and wave energy converters) is determined by many design and environmental factors but timedependent variations in the wind speed are arguably the most important. In this paper we consider a non-Gaussian model for analysing and then simulating wind velocity data. In particular, we consider a Lévy distribution for the statistical characteristics of wind velocity and show how this distribution can be used to derive a stochastic fractional diffusion equation for the wind velocity as a function of time …


Risk Management Trends: Currency Trading Using The Fractal Market Hypothesis, Jonathan Blackledge, Kieran Murphy Jan 2011

Risk Management Trends: Currency Trading Using The Fractal Market Hypothesis, Jonathan Blackledge, Kieran Murphy

Articles

We report on a research and development programme in financial modelling and economic security undertaken in the Information and Communications Security Research Group (ICSRG, 2011) which has led to the launch of a new company - Currency Traders Ireland Limited - funded by Enterprise Ireland. Currency Traders Ireland Limited (CTI, 2011) has a fifty year exclusive license to develop a new set of indicators for analysing currency exchange rates (Forex trading). We consider the background to the approach taken and present examples of the results obtained to date. In this ‘Introduction’, we provide a background to and brief overview of …


Steganography Using Stochastic Diffusion For The Covert Communication Of Digital Images, Jonathan Blackledge, Abdulrahman Al-Rawi Jan 2011

Steganography Using Stochastic Diffusion For The Covert Communication Of Digital Images, Jonathan Blackledge, Abdulrahman Al-Rawi

Articles

This paper is devoted to the study of a method called Stochastic Diffusion for encrypting digital images and embedding the information in another host image or image set. We introduce the theoretical background to the method and the mathematical models upon which it is based. This includes a comprehensive study of the diffusion equation and its properties leading to a convolution model for encrypting data with a stochastic field that is fundamental to the approach considered. Two methods of implementing the approach are then considered. The first method introduces a lossy algorithm for hiding an image in a single host …


Using Virtual Reality To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge, Eugene Coyle Jan 2011

Using Virtual Reality To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge, Eugene Coyle

Articles

— Electricity and the inherent risks associated with its use in the built environment have long since been a priority for the electrical services industry and also the general public who must live and work in this environment. By its nature virtual reality has the advantage of being safe for both the user and equipment. In addition, it offers the user an opportunity to be exposed to a range of scenarios and conditions that either occur infrequently or are hazardous to replicate. This paper presents a prototype desktop virtual reality model, to enhance electrical safety and design in the built …


Dielectric And Optical Study Of Biaxial Bent-Core Nematic Liquid Crystal, S. P. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, C. Keith, C. Tschierske Jan 2011

Dielectric And Optical Study Of Biaxial Bent-Core Nematic Liquid Crystal, S. P. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, C. Keith, C. Tschierske

Articles

We report the observation of biaxial nematic phase in a bent-core molecular system in which the biaxiality exists on a microscopic scale using polarizing microscopy, electro-optics and dielectric spectroscopy. An application of electric field induces a macroscopic biaxiality and therefore electro-optic switching. The observed electro-optic switching is explained in terms of the interaction of the ferroelectric clusters with the electric field. Dielectric spectra of the sample shows existence of low-frequency collective processes related to the microscopic polar clusters. The dielectric constant changes its sign from positive to negative and again to positive values.


The Synchronized Short-Time-Fourier-Transform: Properties And Definitions For Multichannel Source Separation., Ruairí De Fréin, Scott Rickard Jan 2011

The Synchronized Short-Time-Fourier-Transform: Properties And Definitions For Multichannel Source Separation., Ruairí De Fréin, Scott Rickard

Articles

This paper proposes the use of a synchronized linear transform, the synchronized short-time-Fourier-transform (sSTFT), for time-frequency analysis of anechoic mixtures. We address the short comings of the commonly used time-frequency linear transform in multichannel settings, namely the classical short-time-Fourier-transform (cSTFT). We propose a series of desirable properties for the linear transform used in a multichannel source separation scenario: stationary invertibility, relative delay, relative attenuation, and finally delay invariant relative windowed-disjoint orthogonality (DIRWDO). Multisensor source separation techniques which operate in the time-frequency domain, have an inherent error unless consideration is given to the multichannel properties proposed in this paper. The sSTFT …


Rast Model: Simulation Of Tensiotraces To Facilitate Drophad Engineering, Philippe Pringuet, Norman Mcmillan, G. Doyle, Stephen Smith, M. O'Neill, Sebastian Riedel Jan 2011

Rast Model: Simulation Of Tensiotraces To Facilitate Drophad Engineering, Philippe Pringuet, Norman Mcmillan, G. Doyle, Stephen Smith, M. O'Neill, Sebastian Riedel

Articles

Tensiography is a technique that determines the physical and chemical properties of a liquid by illuminating a growing pendant drop from within using a source fibre. Light reflected internally at the surface of the drop is recieved by a collector fibre and is converted into an electric signal called a tensiotrace, which is a graph of reflected light as a function of drop volume. The instrument obtaining this signal is called multianalyser. A numerical model that simulates tensiotraces through a raytracing analysis (RAST - Raytracing Analysis for the Simulation of Tensiotraces) of the multianalyser as been developed to define theoretically …


Protein Replacement Therapy Partially Corrects The Cholesterol-Storage Phenotype In A Mouse Model Of Niemann-Pict Type C2 Disease, Gitte Krogh Nielsen, Frederik Dagnaes-Hansen, Ida Elisabeth Holm, Steve Meaney, Derek Symula, Niels Trolle Andersen, Christian Wurtz Heegaard Jan 2011

Protein Replacement Therapy Partially Corrects The Cholesterol-Storage Phenotype In A Mouse Model Of Niemann-Pict Type C2 Disease, Gitte Krogh Nielsen, Frederik Dagnaes-Hansen, Ida Elisabeth Holm, Steve Meaney, Derek Symula, Niels Trolle Andersen, Christian Wurtz Heegaard

Articles

Niemann-Pick type C2 (NPC2) disease is a fatal autosomal recessive neurovisceral degenerative disorder characterized by late endosomal-lysosomal sequestration of low-density lipoprotein derived cholesterol. The breach in intracellular cholesterol homeostasis is caused by deficiency of functional NPC2, a soluble sterol binding protein targeted to the lysosomes by binding the mannose-6-phosphate receptor. As currently there is no effective treatment for the disorder, we have investigated the efficacy of NPC2 replacement therapy in a murine gene-trap model of NPC2-disease generated on the 129P2/OlaHsd genetic background. NPC2 was purified from bovine milk and its functional competence assured in NPC2-deficient fibroblasts using the specific cholesterol …


An Investigation Of The Subtype Diversity Of Clinical Isolates Of Irish Clostridium Difficile Ribotypes 027 And 078 By Repetitive-Extragenic Palindromic Pcr, Denise Drudy, K. Solomon, S. Murray, L. Scott, S. Mcdermott,, A. Martin, C. O’Donoghue, M. Skally, K. Burns, L. Fenelon, F. Fitzpatrick,, L. Kyne, S. Fanning Jan 2011

An Investigation Of The Subtype Diversity Of Clinical Isolates Of Irish Clostridium Difficile Ribotypes 027 And 078 By Repetitive-Extragenic Palindromic Pcr, Denise Drudy, K. Solomon, S. Murray, L. Scott, S. Mcdermott,, A. Martin, C. O’Donoghue, M. Skally, K. Burns, L. Fenelon, F. Fitzpatrick,, L. Kyne, S. Fanning

Articles

A repetitive-extragenic palindromic PCR (rep-PCR) subtyping method (DiversiLab) in conjunction with ribotyping, toxinotyping and antimicrobial-susceptibility testing was used to detect subtypes within Clostridium difficile ribotypes 027 and 078. Clinical isolates of ribotypes 027 (toxinotype III) (n530) and 078 (toxinotype V) (n523) were provided by health-care facilities across the Republic of Ireland over 2 months in 2006 and 1 month in 2009. Ribotype 027 isolates were significantly more related to each other (9 different subtype profiles) when compared to ribotype 078 isolates (14 different profiles) (P50.001; cut-off .90 % similarity). Almost half of ribotype 078 isolates (45.5 %) showed no relationship …


Quantification Of Unfractionated Heparin In Human Plasma And Whole Blood By Means Of Novel Fluorogenic Anti-Fxa Assays, Vanessa Castro-Lopez, Leanne F. Harris, James S. O'Donnell, Anthony J. Killard Jan 2011

Quantification Of Unfractionated Heparin In Human Plasma And Whole Blood By Means Of Novel Fluorogenic Anti-Fxa Assays, Vanessa Castro-Lopez, Leanne F. Harris, James S. O'Donnell, Anthony J. Killard

Articles

Novel and sensitive plate-based fluorogenic anti-factor Xa (FXa) assays were investigated to quantify unfractionated heparin (UFH) in human plasma and whole blood within the therapeutic ranges of 0–1.6 U/mL and 0–0.8 U/mL, respectively. Two fluorogenic anti-FXa assay methods were defined for low (0–0.6 U/mL) and high (0.6–1.2 U/mL) pharmacologically relevant UFH concentration ranges in pooled human plasma. In both cases significant differences were observed at intervals of 0.2 U/mL (P < 0.05). The semi-logarithmic plots of the calibration curves in the low and high UFH range were both fitted to linear regressions with correlation coefficients of 0.96 and >0.99, respectively. The assay was also optimized for whole blood which was capable of differentiating UFH concentrations at intervals of 0.2 U/mL (P < 0.05) in the range of 0–0.4 U/mL. The statistically different results were fitted to a linear regression with a correlation coefficient of >0.99. The results obtained in this study …


Development Of A Vessel Mimicking Material For Use In Anatomically Realistic Doppler Flow Phantoms, Deirdre King, Carmel Moran, John Mcnamara, Andrew Fagan, Jacinta Browne Jan 2011

Development Of A Vessel Mimicking Material For Use In Anatomically Realistic Doppler Flow Phantoms, Deirdre King, Carmel Moran, John Mcnamara, Andrew Fagan, Jacinta Browne

Articles

Polyvinyl alcohol cryogel, (PVA-C) is presented as a vessel mimicking material for use in anatomically realistic Doppler flow phantoms. Three different batches of 10 % wt PVA-C containing (i) PVA-C alone, (ii) PVA-C with anti-bacterial agent and (iii) PVA-C with silicon carbide particles were produced, each with 1 to 6 freeze-thaw cycles. The resulting PVA-C samples were characterized acoustically (over a range 2.65 - 10.5 MHz) and mechanically in order to determine the optimum mixture and preparation for mimicking the properties of healthy and diseased arteries found in vivo. This optimum mix was reached with the PVA-C with anti-bacterial agent …


Psychophysical Impact And Optical And Morphological Characteristics Of Symptomatic Non-Advanced Cataract., S. Charalampidou, J. Nolan, James Loughman, J. Stack, Lorraine Cassidy, S. Beatty Jan 2011

Psychophysical Impact And Optical And Morphological Characteristics Of Symptomatic Non-Advanced Cataract., S. Charalampidou, J. Nolan, James Loughman, J. Stack, Lorraine Cassidy, S. Beatty

Articles

Purpose To investigate whether
/="/">psychophysical, morphological, and/or optical
/="/">characteristics of symptomatic non-advanced
/="/">cataract are complementary to, or more
/="/">appropriate than, visual acuity (VA) for the
/="/">purposes of recording visual data that reflect
/="/">subjective visual difficulty in patients with
/="/">cataract that exhibit relative sparing of high
/="/">contrast acuity (0.4 logarithm of minimal angle
/="/">of resolution (logMAR) scale or better).


Nano-Enhanced Food Contact Materials And The In Vitro Toxicity To Human Intestinal Cells Of Nano-Zno At Low Dose, Gordon Chambers, Niall Ó Claonadh, Alan Casey, Clement Higginbotham, Sean Lyons, Sanchali Mukherjee Jan 2011

Nano-Enhanced Food Contact Materials And The In Vitro Toxicity To Human Intestinal Cells Of Nano-Zno At Low Dose, Gordon Chambers, Niall Ó Claonadh, Alan Casey, Clement Higginbotham, Sean Lyons, Sanchali Mukherjee

Articles

Nano Zinc Oxide (nZnO) has been shown to display antimicrobial effects which have lead to its application in a number of areas such as antimicrobial surface coatings, anti bacterial wound dressings and more recently in polymer composite systems for use in food contact materials. Concerns have been raised due to the incorporation of nanoparticles in food packaging stemming from the possibility of repeated low dose direct exposure, through ingestion, primarily due to degradation and nanoparticle leaching from the polymer composite. To address these concerns, composites consisting of nZnO and polyethylene were formed using twin screw extrusion to mimic commercial methods …


In-Plane Sensitive Electronic Speckle Pattern Interferometer Using A Diffractive Holographic Optical Element, Raghavendra Jallapuram, Con Healy, Emilia Mihaylova, Vincent Toal Jan 2011

In-Plane Sensitive Electronic Speckle Pattern Interferometer Using A Diffractive Holographic Optical Element, Raghavendra Jallapuram, Con Healy, Emilia Mihaylova, Vincent Toal

Articles

We describe a student project in electronic speckle pattern interferometry. The project includes holographic recording of diffraction gratings in thick, self-processing photopolymer layers made from off-the-shelf chemicals. The gratings are employed in a simple electronic speckle pattern interferometer to measure in-plane rotation.


Comment On C.E. Close, M.R. Gleeson And J.T. Sheridan "Monomer Diffusion Rates In Photopolymer Material Part 1. Low Spatial Frequency Holographic Gratings, Vincent Toal, Suzanne Martin, Izabela Naydenova Jan 2011

Comment On C.E. Close, M.R. Gleeson And J.T. Sheridan "Monomer Diffusion Rates In Photopolymer Material Part 1. Low Spatial Frequency Holographic Gratings, Vincent Toal, Suzanne Martin, Izabela Naydenova

Articles

COMMENT: on C. E. Close, M. R. Gleeson and J. T. Sheridan “Monomer diffusion rates in photopolymer material.Part I. Low spatial frequency holographic gratings” J. Opt. Soc. Am. B / Vol. 28, No. 4 / April 2011 pp 658- 666 [1]


Increased Tolerance To Abiotic Stresses In Tobacco Plants Expressing A Barley Cell Wall Peroxidase, Philippe Pringuet, Norman Mcmillan, Greg Doyle, Stephen Smith, Sebastian Riedel Jan 2011

Increased Tolerance To Abiotic Stresses In Tobacco Plants Expressing A Barley Cell Wall Peroxidase, Philippe Pringuet, Norman Mcmillan, Greg Doyle, Stephen Smith, Sebastian Riedel

Articles

Tensiography is a technique that determines the physical and chemical properties of a liquid by illuminating a growing pendant drop from within using a source fibre. Light reflected internally at the surface of the drop is recieved by a collector fibre and is converted into an electric signal called a tensiotrace, which is a graph of reflected light as a function of drop volume. The instrument obtaining this signal is called multianalyser. A numerical model that simulates tensiotraces through a raytracing analysis (RAST - Raytracing Analysis for the Simulation of Tensiotraces) of the multianalyser as been developed to define theoretically …


Mitophagy And Mitochondrial Morphology In Human Melanoma-Derived Cells Post Exposure To Simulated Sunlight, Luciene M. Zanchetta, Amaya Garcia, Fiona Lyng, James Walsh, James E.J. Murphy Jan 2011

Mitophagy And Mitochondrial Morphology In Human Melanoma-Derived Cells Post Exposure To Simulated Sunlight, Luciene M. Zanchetta, Amaya Garcia, Fiona Lyng, James Walsh, James E.J. Murphy

Articles

Purpose: To assess changes in mitochondrial morphology and mitophagy induced by simulated sunlight irradiation (SSI) and how these changes are modulated by mitochondrial activity and energy source. Materials and methods: Human malignant amelanotic melanoma A375 cells were pre-treated with either a mitochondrial activity enhancer, uncoupler or were either melanin or glutamine supplemented/starved for 4 hours pre-exposure to sunlight. A Q-Sun Solar Simulator (Q-Lab, Homestead, FL, USA) was employed to expose cells to simulated sunlight. Confocal microscopy imaging of A375 cells co-loaded with mitochondria and lysosome-specific fluorescent dyes was used to identify these organelles and predict mitophagic events. Results: SSI induces …


Successful Engineering And Technology Student Mobility: Key Student Perspectives And Quality Determinants Before, During And After Student Exchange Under The Atlantis Programme, Mike Murphy, Donal Mchale, Michael Dyrenfurth, James Barnes Jan 2011

Successful Engineering And Technology Student Mobility: Key Student Perspectives And Quality Determinants Before, During And After Student Exchange Under The Atlantis Programme, Mike Murphy, Donal Mchale, Michael Dyrenfurth, James Barnes

Articles

The EU-US Agreement through the Atlantis Programmes supports consortia of higher education and training institutions working together at undergraduate or graduate level to improve their educational services, to compare and modernise curricula and to develop joint study programmes with full recognition of credits and qualifications. The EU-US Atlantis Programme funds innovative projects across three strands: mobility projects, double or joint “transatlantic degrees” for students in the EU and US and policy-oriented measures. The main focus of activities must be on transatlantic rather than intra-European or intra-American interactions. Funded activities, such as the development of curricula, joint study programmes, exchanges and …


An International Comparison Of Engineering Programs In Their Emphases And Professional Skills Development, Gul Okudan Kremer, Mike Murphy, Brian Bowe Jan 2011

An International Comparison Of Engineering Programs In Their Emphases And Professional Skills Development, Gul Okudan Kremer, Mike Murphy, Brian Bowe

Articles

In the face of grand challenges for engineering, several efforts have been undertaken to identify the vision for what we should expect from our undergraduate engineering students. For example, one of the significant reports indicates that our graduates should aspire “to have the ingenuity of Lillian Gilbreth, the problem solving capabilities of Gordon Moore, the scientific insight of Albert Einstein, the creativity of Pablo Picasso, the determination of the Wright brothers, the leadership abilities of Bill Gates, the conscience of Eleanor Roosevelt, the vision of Martin Luther King, and the curiosity and wonder of our grandchildren.” This statement implies that …


Critical Issues And Lessons Learned In Establishing Concurrent International Ms Degree Programs In Engineering Technology, Mike Murphy, Michael Dyrenfurth, Gary Bertoline, Robert Herrick, Kathryne Newton, Sancho Maria-Ribera, Nuria Castell, James Barnes, Matthias Kuder, Gareth O'Donnell Jan 2011

Critical Issues And Lessons Learned In Establishing Concurrent International Ms Degree Programs In Engineering Technology, Mike Murphy, Michael Dyrenfurth, Gary Bertoline, Robert Herrick, Kathryne Newton, Sancho Maria-Ribera, Nuria Castell, James Barnes, Matthias Kuder, Gareth O'Donnell

Articles

Globalization, competitiveness, and innovation are frequently employed themes as governments, business and industry and universities attempt to respond to the challenges facing them. Clearly business as usual is not likely to be successful in the future. One strategic response for universities has been a significant impetus – in many parts of the world – towards dual, joint or concurrent degree programs involving international partners. It is perhaps not surprising that engineering is among the disciplines that make most use of international collaboration but it seems that engineering technology programs do not yet participate as extensively in this aspect of international …


Lead Silicate Glass Microsphere Resonators With Absorption-Limited Q, Pengfei Wang, Genapathy Murugan, Timothy Lee, Xian Feng, Yuliya Semenova, Qiang Wu, Wei Loh, Gilberto Brambilla, James Wilkinson, Gerald Farrell Jan 2011

Lead Silicate Glass Microsphere Resonators With Absorption-Limited Q, Pengfei Wang, Genapathy Murugan, Timothy Lee, Xian Feng, Yuliya Semenova, Qiang Wu, Wei Loh, Gilberto Brambilla, James Wilkinson, Gerald Farrell

Articles

We report the fabrication and characterization of a lead-silicate glass microsphere resonator. We show that at the wavelengths near 1555 nm high Q modes can be efficiently excited from a 109 μm diameter lead-silicate glass microsphere via evanescent coupling using a tapered silica fiber with a waist diameter of 2 μm. Resonances with Q-factors as high as 0.9×107 were observed. This is very close to the theoretical material-limited Q-factor and is the highest Q-factor reported so far from a nonlinear glass microsphere.


A Comprehensive Analysis Verified By Experiment Of A Refractometer Based On An Smf28–Small-Core Singlemode Fiber (Scsmf)–Smf28 Fiber Structure, Qiang Wu, Yuliya Semenova, Pengfei Wang, Gerald Farrell Jan 2011

A Comprehensive Analysis Verified By Experiment Of A Refractometer Based On An Smf28–Small-Core Singlemode Fiber (Scsmf)–Smf28 Fiber Structure, Qiang Wu, Yuliya Semenova, Pengfei Wang, Gerald Farrell

Articles

A comprehensive theoretical model for an SMF28–small-core SMF (SCSMF)–SMF28 structure based refractometer is developed based on the modal propagation analysis (MPA) method. The simulation result shows that the wavelength shift of this refractometer changes exponentially as the surrounding refractive index (SRI) varies. The core diameter of SCSMF does not have a significant influence on the sensitivity of the refractometer but cladding diameter does have. The simulation results are verified experimentally and it is also experimentally demonstrated that there is a maximum sensitivity of 1808 nm/RIU (refractive index unit) for an SRI range from 1.324 to 1.431 and that, as expected, …


Currency Trading Using The Fractal Market Hypothesis, Jonathan Blackledge, Kieran Murphy Jan 2011

Currency Trading Using The Fractal Market Hypothesis, Jonathan Blackledge, Kieran Murphy

Articles

We report on a research and development programme in financial modelling and economic security undertaken in the Information and Communications Security Research Group (ICSRG, 2011) which has led to the launch of a new company - Currency Traders Ireland Limited - funded by Enterprise Ireland. Currency Traders Ireland Limited (CTI, 2011) has a fifty year exclusive license to develop a new set of indicators for analysing currency exchange rates (Forex trading). We consider the background to the approach taken and present examples of the results obtained to date.


Single Mode Optical Fiber Based Refractive Index Sensor Using Etched Cladding, Ajay Kumar, Geeta Gupta, Arun Mallik, Anuj Bhatnagar Jan 2011

Single Mode Optical Fiber Based Refractive Index Sensor Using Etched Cladding, Ajay Kumar, Geeta Gupta, Arun Mallik, Anuj Bhatnagar

Articles

The use of optical fiber for sensor applications is a topic of current interest. We report the fabrication of etched single mode optical fiber based refractive index sensor. Experiments are performed to determine the etch rate of fiber in buffered hydrofluoric acid, which can be high or low depending upon the temperature at which etching is carried out. Controlled wet etching of fiber cladding is performed using these measurements and etched fiber region is tested for refractive index sensing application. We report significant optical power change in fiber sensor at 1550 nm wavelength, in the presence of IPAsolution and also …