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Electronic Speckle Pattern Shearing Interferometry For Nondestructive Testing Of Thermal Sprayed Alloy Coatings, Yueqiang Xue, David Kennedy, Emilia Mihaylova Jan 2005

Electronic Speckle Pattern Shearing Interferometry For Nondestructive Testing Of Thermal Sprayed Alloy Coatings, Yueqiang Xue, David Kennedy, Emilia Mihaylova

Conference Papers

Thermal sprayed coatings have wide engineering applications. There now exists a wide range of destructive and nondestructive testing (NDT) methods for surface coating inspections. This paper describes an application of Electronic Speckle Pattern Shearing Interferometry (ESPSI) for NDT of thermal sprayed surface coatings. In contrast to other conventional methods such as eddy current, ultrasonic or X-ray, ESPSI allows fast and large survey area inspection. Experimental results of shearographic measurements are presented. Thermal sprayed coatings were tested using ESPSI. Delaminations of the coatings were detected and the fringe patterns were captured using this method. It is shown that the shearography technique …

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Attitudes Towards Electronic Purchasing In The Irish Construction Industry, Alan V. Hore, Roger West Jan 2005

Attitudes Towards Electronic Purchasing In The Irish Construction Industry, Alan V. Hore, Roger West

Conference papers

It is well known that the adoption of information technology in materials procurement in the construction industry has been sporadic and piecemeal. Very significant inefficiencies and problems still exist in both paper transactions and non-integrated electronic solutions. There is a general lack of awareness and take-up of information communication technologies (ICT) within the Irish construction material purchasing supply chain. In order to verify this contention a methodology was adopted which involved the design and distribution of an on-line questionnaire to over 100 Irish construction companies. The survey was designed to ascertain the current level of technology take-up in business-to-business (B2B) …

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Onset Detection, Music Transcription And Ornament Detection For The The Traditional Irish Fiddle, Aileen Kelleher, Derry Fitzgerald, Eugene Coyle, Robert Lawlor, Mikel Gainza Jan 2005

Onset Detection, Music Transcription And Ornament Detection For The The Traditional Irish Fiddle, Aileen Kelleher, Derry Fitzgerald, Eugene Coyle, Robert Lawlor, Mikel Gainza

Conference papers

By combining techniques used in previous onset detectors, a system that detects note onsets in traditional Irish fiddle tunes has been implemented. The notes detected also include the most common types of ornamentation played by the fiddle. Ornaments are notes of extremely short duration, at most a fifth the length of a regular note. A Short Time Fourier Transform based sub-band technique, which previously gave good results for the Irish tin whistle, was modified to include a threshold approximation more suitable for the fiddle. This system has been tested on a database of real recorded fiddle tunes and good results …

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Development Of A Computer-Based Violin Teaching Aid: Vitool, Jane Charles, Derry Fitzgerald, Eugene Coyle Jan 2005

Development Of A Computer-Based Violin Teaching Aid: Vitool, Jane Charles, Derry Fitzgerald, Eugene Coyle

Conference papers

This paper considers the development of a violin teaching aid, called ViTool, which is based on violin pedagogy, sound analysis, and comparison of beginner and good player recordings. It is a computer based teaching aid and will ultimately consist of at least four task dependent tools. Typical beginner faults have been identified and features, that best describe them for classification purposes, are considered. The ViTool is not intended as a replacement or electronic teacher, but as a teaching aid. Presently, it seems that no such violin learning aid or tool exists and an opportunity exists for the development of such …

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Single Channel Source Separation Using Short-Time Independent Component Analysis, Dan Barry, Derry Fitzgerald, Eugene Coyle Jan 2005

Single Channel Source Separation Using Short-Time Independent Component Analysis, Dan Barry, Derry Fitzgerald, Eugene Coyle

Conference papers

In this paper we develop a method for the sound source separation of single channel mixtures using Independent Component Analysis within a time-frequency representation of the audio signal. We apply standard Independent Component Analysis techniques to contiguous magnitude frames of the short-time Fourier transform of the mixture. Provided that the amplitude envelopes of each source are sufficiently different, it can be seen that it is possible to recover the independent short-time power spectra of each source. A simple scoring scheme based on auditory scene analysis cues is then used to overcome the source ordering problem ultimately allowing each of the …

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An Experimental Analysis Of The Call Capacity Of Ieee 802.11b Wireless Local Area Networks For Voip Telephony, Brian Keegan Jan 2005

An Experimental Analysis Of The Call Capacity Of Ieee 802.11b Wireless Local Area Networks For Voip Telephony, Brian Keegan

Masters

The use of the Internet to make phone calls is growing in popularity as the Voice over Internet protocol (VoIP) allows users to make phone calls virtually free of charge. The increased uptake of broadband services by domestic users will further increase the use of VoIP telephony. Furthermore, the emergence of low cost wireless networks (namely IEEE 802.11a/b/g WLANs) is expected to bring wireless VoIP into the mainstream. As the number of wireless hotspots increases more users will want to use VoIP calls wherever possible by connecting to open access points (AP). A major concern with VoIP is Quality of …

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An Explicit Mapping Between The Frequency Domain And The Time Domain Representations Of Nonlinear Systems, Marissa Condon, Rossen Ivanov Jan 2005

An Explicit Mapping Between The Frequency Domain And The Time Domain Representations Of Nonlinear Systems, Marissa Condon, Rossen Ivanov

Articles

Explicit expressions are presented that describe the input-output behaviour of a nonlinear system in both the frequency and the time domain. The expressions are based on a set of coefficients that do not depend on the input to the system and are universal for a given system. The anharmonic oscillator is chosen as an example and is discussed for different choices of its physical parameters. It is shown that the typical approach for the determination of the Volterra Series representation is not valid for the important case when the nonlinear system exhibits oscillatory behaviour and the input has a pole …

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Dual-Band Monopole Antenna With Stagger-Tuned Arms For Broadbanding, Max Ammann, Ronan Farrell Jan 2005

Dual-Band Monopole Antenna With Stagger-Tuned Arms For Broadbanding, Max Ammann, Ronan Farrell

Conference papers

The paper describes a dual-band miniaturized printed monopole for integration in modern wireless systems. The printed monopole is augmented with two arms, resonant at slightly different frequencies, providing a broadened response for the upper band. The achieved bandwidth for the high band is 36%. These antennas are proposed for the emerging dual-mode multi-band WLAN transceivers, which operate over a wide range of bands as dictated by national authorities. Measured and simulated data, including return loss, antenna gain and radiation patterns, are presented. The numerical method employed was the finite integration technique.

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Printed Triband Terminal Antenna, Matthias John, Max Ammann, Ronan Farrell Jan 2005

Printed Triband Terminal Antenna, Matthias John, Max Ammann, Ronan Farrell

Articles

This paper presents a printed triple-band multibranch monopole for use in modern wireless systems. The antenna is designed to operate in three bands which cover virtually all wireless channels. Parameters of the antenna geometry are varied and the effects of these variations on the impedance bandwidth are shown.

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Modelling And Control Of A Suspension System For Vehicle Applications, Padraig Dowds, Aidan O'Dwyer Jan 2005

Modelling And Control Of A Suspension System For Vehicle Applications, Padraig Dowds, Aidan O'Dwyer

Conference papers

This paper discusses the modelling of passive and active suspension systems in a car, and the subsequent design of appropriate feedback controllers for the active suspension system. The models will be investigated using a quarter car model and a full car model approach.

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Comparative Study Of Two Techniques For Determining Critical Frequency Response Characteristics, Niall O'Connor, Aidan O'Dwyer Jan 2005

Comparative Study Of Two Techniques For Determining Critical Frequency Response Characteristics, Niall O'Connor, Aidan O'Dwyer

Conference papers

The paper presents a review of a comparative study of two separate techniques for obtaining important frequency and time domain characteristics of a system consisting of a process in series with a PI/PID controller in closed loop. The first technique involves the use of a Pseudo Random Binary Sequence (PRBS) to obtain the closed loop frequency response of the system. This closed loop frequency information may then be manipulated to obtain both open loop frequency response information and process model parameters. A further mathematical simulation using Matlab may then be performed independent of the actual process in order to obtain …

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Pid Control: The Early Years, Aidan O'Dwyer Jan 2005

Pid Control: The Early Years, Aidan O'Dwyer

Conference papers

This contribution outlines controller developments 1788 – c.1900; 1900-1950: The role of instrument companies; early theoretical description of the PID controller; early tuning of the PID controller; some further developments since 1950; some conclusions.

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Optimization Of Impedance Bandwidth For The Printed Rectangular Monopole Antenna, Matthias John, Max Ammann Jan 2005

Optimization Of Impedance Bandwidth For The Printed Rectangular Monopole Antenna, Matthias John, Max Ammann

Articles

This paper describes a printed rectangular-plate monopole fed by microstrip line. The effect of varying the plate width, feed-gap height, and feedline width on the impedance bandwidth is examined. It is shown that for a fixed ground-plane size, that optimization of these parameters can yield an impedance bandwidth ratio of 4.3:1, without using any broadbanding techniques.

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Audio Time-Scale Modification, David Dorran Jan 2005

Audio Time-Scale Modification, David Dorran

Doctoral

Audio time-scale modification is an audio effect that alters the duration of an audio signal without affecting its perceived local pitch and timbral characteristics. There are two broad categories of time-scale modifications algorithms, time-domain and frequency-domain. The computationally efficient time-domain techniques produce high quality results for single pitched signals such as speech, but do not cope well with more complex signals such as polyphonic music. The less efficient frequency-domain techniques have proven to be more robust and produce high quality results for a variety of signals; however they introduce a reverberant artefact into the output. This dissertation focuses on incorporating …

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Future Reasoning Machines: Mind And Body, Brian Duffy, Gregory O'Hare, John Bradley, Bianca Schoen-Phelan Jan 2005

Future Reasoning Machines: Mind And Body, Brian Duffy, Gregory O'Hare, John Bradley, Bianca Schoen-Phelan

Articles

In investing energy in developing reasoning machines of the future, one must abstract away from the specific solutions to specific problems and ask what are the fundamental research questions that should be addressed. This paper aims to revisit some fundamental perspectives and promote new approaches to reasoning machines and their associated form and function. Core aspects are discussed, namely the one-mind-many-bodies metaphor as introduced in the Agent Chameleon work. Within this metaphor the agent’s embodiment form may take many guises with the artificial mind or agent potentially exhibiting a nomadic existence opportunistically migrating between a myriad of instantiated embodiments. We …

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A Compact Electronic Speckle Pattern Interferometry System Using A Photopolymer Reflection Holographic Optical Element, Guntaka Tulasi Sridhar Reddy, Raghavendra Jallapuram, Vincent Toal, Izabela Naydenova, Suzanne Martin, Svetlana Mintova Jan 2005

A Compact Electronic Speckle Pattern Interferometry System Using A Photopolymer Reflection Holographic Optical Element, Guntaka Tulasi Sridhar Reddy, Raghavendra Jallapuram, Vincent Toal, Izabela Naydenova, Suzanne Martin, Svetlana Mintova

Conference Papers

A simple and compact electronic speckle pattern interferometry system using a reflection holographic optical element is presented. The reflection holographic optical element is recorded on an acrylamide based photopolymer formulated and prepared at the Centre for Industrial & Engineering Optics. Light intensity of 40mW/cm2 with an exposure time of 60 seconds was used in fabricating the holographic optical element. The vibration mode patterns of a 4 cm diameter thin circular sheet of brass metal attached to a 4 cm diameter paper cone loud speaker are presented.

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Gene Therapy And Targeted Toxins For Glioma, James Curtin, Gwendalyn King, Marianela Candolfi, Kurt Kroeger, Pedro Lowenstein, Maria Castro Jan 2005

Gene Therapy And Targeted Toxins For Glioma, James Curtin, Gwendalyn King, Marianela Candolfi, Kurt Kroeger, Pedro Lowenstein, Maria Castro

Articles

The most common primary brain tumor in adults is glioblastoma. These tumors are highly invasive and aggressive with a mean survival time of nine to twelve months from diagnosis to death. Current treatment modalities are unable to significantly prolong survival in patients diagnosed with glioblastoma. As such, glioma is an attractive target for developing novel therapeutic approaches utilizing gene therapy. This review will examine the available preclinical models for glioma including xenographs, syngeneic and genetic models. Several promising therapeutic targets are currently being pursued in pre-clinical investigations. These targets will be reviewed by mechanism of action, i.e., conditional cytotoxic, targeted …

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Combining Cytotoxic And Immune-Mediated Gene Therapy To Treat Brain Tumors, James Curtin, Gwendalyn King, Marianela Candolfi, Remy Greeno, Kurt Kroeger, Pedro Lowenstein, Maria Castro Jan 2005

Combining Cytotoxic And Immune-Mediated Gene Therapy To Treat Brain Tumors, James Curtin, Gwendalyn King, Marianela Candolfi, Remy Greeno, Kurt Kroeger, Pedro Lowenstein, Maria Castro

Articles

Glioblastoma (GBM) is a type of intracranial brain tumor, for which there is no cure. In spite of advances in surgery, chemotherapy and radiotherapy, patients die within a year of diagnosis. Therefore, there is a critical need to develop novel therapeutic approaches for this disease. Gene therapy, which is the use of genes or other nucleic acids as drugs, is a powerful new treatment strategy which can be developed to treat GBM. Several treatment modalities are amenable for gene therapy implementation, e.g. conditional cytotoxic approaches, targeted delivery of toxins into the tumor mass, immune stimulatory strategies, and these will all …

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Real-Time Reverse Transcription Pcr For Detection And Quantitative Analysis Of Equine Influenza Virus, Michelle Quinlivan, Eugene Dempsey, Fergus Ryan, Sean Atkins, Ann Cullinane Jan 2005

Real-Time Reverse Transcription Pcr For Detection And Quantitative Analysis Of Equine Influenza Virus, Michelle Quinlivan, Eugene Dempsey, Fergus Ryan, Sean Atkins, Ann Cullinane

Articles

Equine influenza is a cause of epizootic respiratory disease of the equine. The detection of equine influenza virus using real-time Light Cycler reverse transcription (RT)-PCR technology was evaluated over two influenza seasons with the analysis of 171 samples submitted for viral respiratory disease. Increased sensitivity was found in overall viral detection with this system compared to Directigen Flu A and virus isolation, which were 40% and 23%, respectively, that of the RT-PCR. The assay was also evaluated as a viable replacement for the more traditional methods of quantifying equine influenza virus, 50% egg infectious dose and 50% tissue culture infectious …

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Characterisation Of An Acrylamide-Based Photopolymer For Holographic Data Storage, Hosam Sherif Jan 2005

Characterisation Of An Acrylamide-Based Photopolymer For Holographic Data Storage, Hosam Sherif

Masters

An acrylamide-based photopolymer, formulated in the Centre for Industrial and Engineering Optics, was investigated as a recording material for holographic data storage applications. Holographic data storage (HDS) is an optical storage technique, which theoretically allows densities as high as tens of TB/cm2 with data transfer rates of many GB/s/. HDS has unique advantages, such as the ability to perform parallel data searches (associative recall) and implement novel encryption techniques. At present, many materials have been investigated to determine their suitability for use as HDS media. As yet, no one material possesses all the properties that are required to realise the …

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Current And Future Applications Of Surface Engineering, David Kennedy, Yueqiang Xue, Emilia Mihaylova Jan 2005

Current And Future Applications Of Surface Engineering, David Kennedy, Yueqiang Xue, Emilia Mihaylova

Articles

No abstract provided.

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Micro Shot Blasting Of Machine Tools For Improving Surface Finish And Reducing Cutting Forces In Manufacturing, James Vahey, David Kennedy Jan 2005

Micro Shot Blasting Of Machine Tools For Improving Surface Finish And Reducing Cutting Forces In Manufacturing, James Vahey, David Kennedy

Articles

Micro blasting of cutting tips and tools is a very effective and reliable method of advancing the life of tools under the action of turning, milling, drilling, punching and cutting. This paper outlines the ways in which micro blasted tools, both coated and un coated have benefited from shot blasting and resulted in greater productivity, lower cutting forces, improved surface finish of the work pieces and less machine downtime. The process of micro blasting is discussed in the paper. Its effectiveness depends on many parameters including the shot media ad size, the mechanics of impact and the application of the …

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Development And Performance Characteristics Of An Ultrasound Angioplasty Device, Graham Gavin, Garrett Mcguinness, Finbar Dolan, M.S. J. Hashmi Jan 2005

Development And Performance Characteristics Of An Ultrasound Angioplasty Device, Graham Gavin, Garrett Mcguinness, Finbar Dolan, M.S. J. Hashmi

Conference Papers

INTRODUCTION The effect of atherosclerosis is well documented and many procedures such as balloon angioplasty and stentimplantation have been developed to reopen occluded arteries. However, there are considerable differences in the material properties of various atherosclerotic lesions as they develop. Many authors have suggested that rigid calcified plaques may require specific procedures that target this rigid material through de-bulking or complete removal (Salunke et al, 1997). Ultrasound angioplasty is the delivery of high power low frequency ultrasound via a wire waveguide to the lesion location. This results in distal tip wire displacements of up to 100um peak-to-peak (p-p) at frequencies …

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Real-Time Reverse Transcription Pcr For Detection And Quantitative Analysis Of Equine Influenza Virus., Michelle Quinlivan, Eugene Dempsey, Fergus Ryan, Sean Arkins, Ann Cullinnane Jan 2005

Real-Time Reverse Transcription Pcr For Detection And Quantitative Analysis Of Equine Influenza Virus., Michelle Quinlivan, Eugene Dempsey, Fergus Ryan, Sean Arkins, Ann Cullinnane

Articles

Equine influenza is a cause of epizootic respiratory disease of the equine. The detection of equine influenza virus using real-time Light Cycler reverse transcription (RT)-PCR technology was evaluated over two influenza seasons with the analysis of 171 samples submitted for viral respiratory disease. Increased sensitivity was found in overall viral detection with this system compared to Directigen Flu A and virus isolation, which were 40% and 23%, respectively, that of the RT-PCR. The assay was also evaluated as a viable replacement for the more traditional methods of quantifying equine influenza virus, 50% egg infectious dose and 50% tissue culture infectious …

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Characterisation Of An Acrylamide-Based Photopolymer For Data Storage Utilizing Holographic Angular Multiplexing, Hosam Sherif, Izabela Naydenova, Suzanne Martin, Colm Mcginn, Vincent Toal Jan 2005

Characterisation Of An Acrylamide-Based Photopolymer For Data Storage Utilizing Holographic Angular Multiplexing, Hosam Sherif, Izabela Naydenova, Suzanne Martin, Colm Mcginn, Vincent Toal

Articles

An acrylamide-based photopolymer formulated in the Centre for Industrial and Engineering Optics has been investigated with a view to further optimisation for holographic optical storage. Series of 18 to 30 gratings were angularly multiplexed in a volume of photopolymer layer at a spatial frequency of 1500 lines/mm. Since the photopolymer is a saturable material, an exposure scheduling method was used to exploit the entire dynamic range of the material and allow equal strength holographic gratings to be recorded. This investigation yielded the photopolymer M/# for moderately thin layers. Photopolymer temporal stability was also studied by measuring variations of material shrinkage, …

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Holographic Patterning Of Acrylamide-Based Photopolymer Surface, Izabela Naydenova, Emilia Mihaylova, Suzanne Martin, Vincent Toal Jan 2005

Holographic Patterning Of Acrylamide-Based Photopolymer Surface, Izabela Naydenova, Emilia Mihaylova, Suzanne Martin, Vincent Toal

Articles

The patterning of an acrylamide-based photopolymer surface by holographic recording is studied. The patterns are induced by light alone and no post-processing is required. Periodic surface modulation is observed in addition to a volume phase grating. An investigation has been carried out using white light interferometry into the dependence of the amplitude of the photo induced surface relief modulation on the spatial frequency, intensity of recording and sample thickness. The observed dependencies indicate that the diffusion of material during the holographic recording plays a major role in surface relief formation. The possibility for inscription of surface relief patterns opens the …

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Modernization Of The Hilger And Watts Guage-Block Interferometer, Michael O'Hora, Brian Bowe, Vincent Toal, Sean Peyton Jan 2005

Modernization Of The Hilger And Watts Guage-Block Interferometer, Michael O'Hora, Brian Bowe, Vincent Toal, Sean Peyton

Articles

The Hilger & Watts gauge-block interferometer was designed and manufactured commercially in the 1950s. The instrument uses isotope lamps as wavelength standards to perform absolute length calibration of gauge blocks (slip gauges) up to 100 mm in length, to an accuracy of approximately 1 ppm. It is entirely manually operated. In order to make the instrument more suitable for the modern laboratory, new hardware has been added, and a customized software package developed to automate the measurement process. This paper shows how interferograms may be imaged successfully at each of the eight available wavelengths, and the critical fringe fraction measurement …

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The Compact, Issue 2, 24th Of October, 2005, Dit: Students' Union Jan 2005

The Compact, Issue 2, 24th Of October, 2005, Dit: Students' Union

DIT Student Union

No abstract provided.

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The Compact, Issue 1, 3rd Of October, 2005, Dit: Students' Union Jan 2005

The Compact, Issue 1, 3rd Of October, 2005, Dit: Students' Union

DIT Student Union

No abstract provided.

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Onset And Ornament Detection And Music Transcription For Monophonic Traditional Irish Music, Aileen Kelleher Jan 2005

Onset And Ornament Detection And Music Transcription For Monophonic Traditional Irish Music, Aileen Kelleher

Masters

To date, much has been... This abstract will be longer in due course!

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