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2009

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Emitter-Wrap-Through Photovoltaic Dipole Antenna With Solar Concentrator, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton Jan 2009

Emitter-Wrap-Through Photovoltaic Dipole Antenna With Solar Concentrator, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton

Articles

A novel photovoltaic dipole antenna employing a solar concentrator as a reflector is proposed. Four identical emitter-wrap-through rear contact solar cells connected in series as a folded dipole are simultaneously used for power generation and as the antenna radiating element, which is located in the focal line of a parabolic solar concentrator. The parabolic structure acts as a solar concentrator for the photovoltaic cells as well as a reflector for the folded dipole antenna. Full-wave electromagnetic simulation with supportive experimental work validates this design. The measured fractional impedance bandwidth and gain were 21% and 11.1 dBi, respectively. The antenna/solar arrangement …

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Generalised Design Process For Fiber-Bend-Loss-Based Edge Filters For A Wavelength Measurement System, Pengfei Wang, Gerald Farrell, Yuliya Semenova Jan 2009

Generalised Design Process For Fiber-Bend-Loss-Based Edge Filters For A Wavelength Measurement System, Pengfei Wang, Gerald Farrell, Yuliya Semenova

Articles

We investigate and present a generalized methodology for the design of a fiber-bend-loss-based edge filter, starting with the task of evaluating and selecting suitable fibers and then considering the design of a fiber-bending-loss edge filter. As an example to illustrate the methodology, a Corning SMF28e fiber with a 900 μmdiameter is selected and two sample edge filters are designed for experimental verification. The designed edge filters are compact, easy to fabricate, meet target spectral specifications, and show low polarization-dependent loss, confirming the effectiveness of the proposed methodology for fiber-bend-loss-based edge filter design.

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Microstrip-Fed Dual-Frequency Annular-Slot Antenna Loaded By Split-Ring-Slot, Xiulong Bao, Max Ammann Jan 2009

Microstrip-Fed Dual-Frequency Annular-Slot Antenna Loaded By Split-Ring-Slot, Xiulong Bao, Max Ammann

Articles

A compact dual-band annular-slot antenna loaded by a concentric split-ring-slot is presented. A stepped microstrip feedline enables the control of the coupling and provides good matching. The annular-slot is connected to the split-ring-slot by a rectangular slot, which increases the surface of the current path, thus notably reducing the resonant frequency for a given size. The embedded split-ring-slot structure allows many resonant modes to be realised. By tuning the key parameters, these operating modes and their bandwidths can be controlled. A wide bandwidth can be realised for either the lower band, upper band or both bands simultaneously, depending on the …

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Sms Fibre Structure For Temperature Measurement Using A Simple Intensity-Based Interrogation System, Agus Hatta, Ginu Rajan, Yuliya Semenova, Gerald Farrell Jan 2009

Sms Fibre Structure For Temperature Measurement Using A Simple Intensity-Based Interrogation System, Agus Hatta, Ginu Rajan, Yuliya Semenova, Gerald Farrell

Articles

A singlemode–multimode–singlemode (SMS) fibre structure for temperature measurement that utilises a simple intensity-based interrogation system is proposed. The temperature dependence of the SMS fibre structure utilised as a sensor is investigated numerically and experimentally. It is found that a strong temperature dependence for the SMS fibre structure exists at selected wavelengths. The temperature characteristic at such wavelengths is linear in nature and can be used for temperature measurements. The proposed temperature sensor offers a high resolution and accuracy, and also benefits from a simple configuration and low cost when compared to other fibre-optic temperature sensors.

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Use Of A Single-Multiple-Single-Mode Fiber Filter For Interrogating Fiber Bragg Grating Strain Sensors With Dynamic Temperature Compensation, Qiang Wu, Muhammad Hatta, Yuliya Semenova, Gerald Farrell Jan 2009

Use Of A Single-Multiple-Single-Mode Fiber Filter For Interrogating Fiber Bragg Grating Strain Sensors With Dynamic Temperature Compensation, Qiang Wu, Muhammad Hatta, Yuliya Semenova, Gerald Farrell

Articles

An interrogation technique for fiber Bragg grating (FBG) strain sensors with dynamic temperature compensation using a single-multiple-single-mode (SMS) fiber filter as a temperature compensating element is presented. Experimental results show that this technique offers a resolution of better than 3:4 με for strain measurements in the range from 0 to 1667 με, and the temperature induced error is as low as 34 με in the temperature range from 10 to 60 °C. The temperature induced error could be further reduced if the temperature sensitivity (the rate of temperature induced wavelength shift) of the SMS filter was closer to that of …

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Analysis Of Assessment Strategies Used In A Level 7, Year 1 Engineering Subject, Aidan O'Dwyer Jan 2009

Analysis Of Assessment Strategies Used In A Level 7, Year 1 Engineering Subject, Aidan O'Dwyer

Conference papers

This contribution critically analyses the assessment strategies used on the core Electrical Systems subject in the first year of a three-year, Level 7, degree programme in Electrical Engineering at Dublin Institute of Technology. An evidence-based approach is taken, by analysing the assessment data in detail.

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Estimating Dysphonia Severity In Continuous Speech: Application Of A Multi-Parameter Spectral/Cepstral Model, Christopher Dromey, Shaheen N. Awan, Nelson Roy Jan 2009

Estimating Dysphonia Severity In Continuous Speech: Application Of A Multi-Parameter Spectral/Cepstral Model, Christopher Dromey, Shaheen N. Awan, Nelson Roy

Faculty Publications

The purpose of the study was to identify a sub-set of spectral/cepstral-based analysis methods that would most effectively predict dysphonia severity (as estimated via auditory-perceptual analysis) in samples of continuous speech. Acoustic estimates of dysphonia severity were used as an objective treatment outcomes measure in a set of pre- vs post-treatment speech samples. Pre- and post-treatment continuous speech samples from 104 females with primary muscle tension dysphonia (MTD) were rated by listeners using a 100 point visual analogue scale (VAS) and analysed acoustically with spectral/cepstral-based measures. Stepwise linear regression produced a three-factor model consisting of the cepstral peak prominence (CPP); …

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Laryngeal-Level Amplitude Modulation In Vibrato, Christopher Dromey, Lorie Reese, J Arden Hopkin Jan 2009

Laryngeal-Level Amplitude Modulation In Vibrato, Christopher Dromey, Lorie Reese, J Arden Hopkin

Faculty Publications

Summary: The goal of this investigation was to test a new methodology for measuring amplitude modulation (AM) at the level of the vocal folds during vibrato in trained singers, because previous research has suggested that AM arises in large part as an acoustic epiphenomenon through an interaction of the harmonics in the laryngeal source with the resonances of the vocal tract as the fundamental frequency oscillates. A within-subjects model was used to compare vocal activity across three pitch and three loudness conditions. Seventeen female singers with a range of training and experience were recorded with a microphone and an electroglottograph …

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Articulatory Changes In Muscle Tension Dysphonia: Evidence Of Vowel Space Expansion Following Manual Circumlaryngeal Therapy, Christopher Dromey, Nelson Roy, Shawn L. Nissen, Shimon Sapir Jan 2009

Articulatory Changes In Muscle Tension Dysphonia: Evidence Of Vowel Space Expansion Following Manual Circumlaryngeal Therapy, Christopher Dromey, Nelson Roy, Shawn L. Nissen, Shimon Sapir

Faculty Publications

In a preliminary study, we documented significant changes in formant transitions associated with successful manual circumlaryngeal treatment (MCT) of muscle tension dysphonia (MTD), suggesting improvement in speech articulation. The present study explores further the effects of MTD on vowel articulation by means of additional vowel acoustic measures. Pre- and post-treatment audio recordings of 111 women with MTD were analyzed acoustically using two measures: vowel space area (VSA) and vowel articulation index (VAI), constructed using the first (F1) and second (F2) formants of 4 point vowels/ ", i, æ, u/, extracted from eight words within a standard reading passage. Pairwise t-tests …

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Information Hiding By Stochastic Disfusion And Its Application To Printed Document Authentication, Jonathan Blackledge, Eugene Coyle Jan 2009

Information Hiding By Stochastic Disfusion And Its Application To Printed Document Authentication, 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-O-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, information hiding and covert encryption methods which can be applied to both electronic and printed images (and documents) for the purposes of authentication, prevent unauthorized copying and, in the …

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Social Or Academic Language Intervention? You Don’T Have To Choose, Lee Robinson Jan 2009

Social Or Academic Language Intervention? You Don’T Have To Choose, Lee Robinson

Faculty Publications

Students with a variety of types of language impairments exhibit deficits that affect both social interactions and academic performance. Two types of theory of mind underlie social and academic language skills: interpersonal and intrapersonal. In this article, the authors describe strategies for developing interpersonal and intrapersonal theory of mind abilities with the goal of promoting the inferencing skills essential for comprehension of social and academic language.

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Exploratory Study Investigating The Opinions Of Russian-Speaking Parents On Maintaining Their Children's Use Of The Russian Language, Sue Kraftsoff, Sarah Quinn Jan 2009

Exploratory Study Investigating The Opinions Of Russian-Speaking Parents On Maintaining Their Children's Use Of The Russian Language, Sue Kraftsoff, Sarah Quinn

Irish Journal of Applied Social Studies

This study explored why and how Russian speaking parents in an Irish context maintained the Russian language in their school-age children. Using a self-administered unstandardised questionnaire, the opinions of 16 Russian-speaking parents, reporting on 24 children, were surveyed. Of this sample, five parents were then interviewed using focus group methodology. The main findings revealed that Russian-speaking parents living in Ireland strongly supported Russian language maintenance in their families and wanted their children to be as fluent as possible in the Russian language. The reasons for the support of Russian language were: cultural preservation, general knowledge of languages in addition to …

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The Potential Of Asynchronous Video In Online Education, Michael E. Griffiths, Charles R. Graham Jan 2009

The Potential Of Asynchronous Video In Online Education, Michael E. Griffiths, Charles R. Graham

Faculty Publications

There are differences in the benefits that are afforded by the two extremes of face-to-face and distance education. University campus courses are based on the assumption that the student community and interaction between learners and an expert teacher in the same physical location is essential to the learning process. In comparison, distance education provides a learner with flexibility, individualized learning, lower costs, and self-determination in the learning process. Much research has been invested into modern approaches that may be able to harness key benefits from both face-to-face and distance education. One recent breakthrough has come in the use of asynchronous …

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Tpack Development In Science Teaching: Measuring The Tpack Confidence Of Inservice Science Teachers, Charles R. Graham, Nicolette Burgoyne, Pamela Cantrell, Leigh Smith, Larry St. Clair, Ron Harris Jan 2009

Tpack Development In Science Teaching: Measuring The Tpack Confidence Of Inservice Science Teachers, Charles R. Graham, Nicolette Burgoyne, Pamela Cantrell, Leigh Smith, Larry St. Clair, Ron Harris

Faculty Publications

Knowledge related to the effective use of educational technologies has become widely recognized as an important aspect of an educator’s knowledge-base for the 21st Century (ISTE, 2008; National Council for Accreditation of Teacher Education, 1997; Partnership for 21st Century Skills, 2003). Early in the history of educational technology, educators were taught in technology classes that focused primarily on technology skills independent from the pedagogical or content courses (Graham, Culatta, Pratt, & West, 2004; Hargrave & Hsu, 2000; Willis & Mehlinger, 1996). Educators soon recognized that technology skills alone did not serve them well because one could know how to operate …

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The Balanced Scorecard As A Strategy-Evaluation Tool: The Effects Of Implementation Involvement And A Causal-Chain Focus, William B. Tayler Jan 2009

The Balanced Scorecard As A Strategy-Evaluation Tool: The Effects Of Implementation Involvement And A Causal-Chain Focus, William B. Tayler

Faculty Publications

This paper uses an experiment to examine whether involvement in scorecard implementation can mitigate the effects of motivated reasoning that occur when the scorecard is framed as a causal chain rather than merely as a balanced set of measures. Psychological research on motivated reasoning suggests that managers will evaluate and interpret data in ways consistent with their preferences, increasing their tendency to arrive at conclusions that are consistent with their desired conclusions (Kunda 1990). Consistent with that research, results of my study show that managers who are involved in selecting strategic initiatives perceive those initiatives as having been more successful …

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Modelling And Simulation Of A Biomass Gasification-Solid Oxide Fuel Cell Combined Heat And Power Plant Using Aspen Plus, Wayne Doherty, Anthony Reynolds, David Kennedy Jan 2009

Modelling And Simulation Of A Biomass Gasification-Solid Oxide Fuel Cell Combined Heat And Power Plant Using Aspen Plus, Wayne Doherty, Anthony Reynolds, David Kennedy

Conference Papers

In this paper the operation and performance of a high temperature solid oxide fuel cell (SOFC) stack on biomass syn-gas from a demonstration biomass gasification combined heat and power (CHP) plant is investigated. The objective of this work is to develop a computer simulation model of a biomass-SOFC CHP system, flexible enough for use in industry, capable of predicting system performance under various operating conditions and using diverse fuels. The biomass gasifier is of the dual fluidised bed (DFB) type with steam as the gasifying agent and is operated at atmospheric pressure. The tubular SOFC configuration, developed by Siemens Power …

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Toast, Vol 1, Issue 3, 2009, Dit:Students Union Jan 2009

Toast, Vol 1, Issue 3, 2009, Dit:Students Union

DIT Student Union

No abstract provided.

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Toast, Vol 1, Issue 5, 2009, Dit Students Union Jan 2009

Toast, Vol 1, Issue 5, 2009, Dit Students Union

DIT Student Union

No abstract provided.

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Toast, Vol. 1, Issue 6, 2009, Dit Students Union Jan 2009

Toast, Vol. 1, Issue 6, 2009, Dit Students Union

DIT Student Union

No abstract provided.

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Rankings And The Global “Battle For Talent", Ellen Hazelkorn Jan 2009

Rankings And The Global “Battle For Talent", Ellen Hazelkorn

Books/Book chapters

This chapter will look at the impact that rankings are having on student choice and mobility, and the way in which both higher education institutions (HEIs) and government are responding to global competition for talent. It draws on the results of an international survey of HE leaders in 2006 and interviews with HEIs in Australia, Japan and Germany during 2008. The research was conducted under the auspices of the OECD Programme for Institutional Management of Higher Education, the International Association of Universities, and the Institute of Higher Education Policy—the latter with funding from the Lumina Foundation. There are three main …

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A Brief Feedback Intervention For Diagnostic Overshadowing, David Wood, Terence J.G. Tracey Jan 2009

A Brief Feedback Intervention For Diagnostic Overshadowing, David Wood, Terence J.G. Tracey

Faculty Publications

Clinical decision-making errors are well-documented among both experienced clinicians and students. One robust clinical decision-making error is called diagnostic overshadowing (DO), which occurs when the presence of one diagnosis interferes with the detection of other diagnoses. This study tested whether two types of instruction and brief feedback interventions reduced the likelihood of DO. Specifically, content-based feedback and principle-based feedback significantly reduced the likelihood of DO among doctoral students in clinical and counseling psychology. An intervention effect was found when the training task and the target task were highly similar. Recommendations for improving diagnostic decision-making among trainees in professional psychology are …

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'Country Life'? Rurality, Folk Music And 'Show Of Hands', Richard Yarwood, Clive Charlton Jan 2009

'Country Life'? Rurality, Folk Music And 'Show Of Hands', Richard Yarwood, Clive Charlton

School of Geography, Earth and Environmental Sciences

No abstract provided.

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Holographic Recording In Acrylamide Photopolymers: Thickness Limitations, Mohammad Mahmud, Izabela Naydenova, Nitesh Pandey, Tzvetanka Babeva, Raghavendra Jallapuram, Suzanne Martin, Vincent Toal Jan 2009

Holographic Recording In Acrylamide Photopolymers: Thickness Limitations, Mohammad Mahmud, Izabela Naydenova, Nitesh Pandey, Tzvetanka Babeva, Raghavendra Jallapuram, Suzanne Martin, Vincent Toal

Articles

Holographic recording in thick photopolymer layers is important for application in holographic data storage, volume holographic filters and correlators. Here, the characteristics of acrylamidebased photopolymer layers having thickness from 250 μm to 1-mm were studied. For each layer thickness samples with three different values of absorbance were studied. By measuring both the first order diffraction efficiency growth of holographically recorded gratings and studying the diffraction patterns obtained, the influence of scattering on the diffraction efficiency of thick volume holographic gratings was analyzed. It was observed that above a particular thickness and absorbance, the first order diffraction efficiency significantly decreased because …

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Output Feedback Adaptive Control Of A Class Of Nonlinear Discrete-Time Systems With Unknown Control Directions, C Yang, Ss Ge, Th Lee Jan 2009

Output Feedback Adaptive Control Of A Class Of Nonlinear Discrete-Time Systems With Unknown Control Directions, C Yang, Ss Ge, Th Lee

School of Engineering, Computing and Mathematics

In this paper, output feedback adaptive control is investigated for a class of nonlinear systems in output-feedback form with unknown control gains. To construct output feedback control, the system is transformed into the form of the NARMA (nonlinear-auto-regressive-moving-average) model, based on which future output prediction is carried out. With employment of the predicted future output, a constructive output feedback adaptive control is given with the discrete Nussbaum gain exploited to overcome the difficulty due to unknown control directions. Under the global Lipschitz condition of the system functions, the boundedness of all the closed-loop signals and asymptotical output tracking are achieved …

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Impact Of Land Fragmentation And Resource Ownership On Productivity And Efficiency: The Case Of Rice Producers In Bangladesh, S Rahman, M Rahman Jan 2009

Impact Of Land Fragmentation And Resource Ownership On Productivity And Efficiency: The Case Of Rice Producers In Bangladesh, S Rahman, M Rahman

School of Geography, Earth and Environmental Sciences

The paper analyzes the impact of land fragmentation and ownership of resources on productivity and technical efficiency in rice production in Bangladesh using farm level survey data. Results reveal that land fragmentation has a significant detrimental effect on productivity and efficiency as expected. The elasticity estimates of land fragmentation reveal that a 1% increase in land fragmentation reduces rice output by 0.05% and efficiency by 0.03%. On the other hand, ownership of key resources (land, family labour, and draft animals) significantly increases efficiency. The mean elasticity estimates reveal that a 1% increase in family labour and owned draft animal improve …

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Farm Productivity And Efficiency In Rural Bangladesh: The Role Of Education Revisited, Mn Asadullah, S Rahman Jan 2009

Farm Productivity And Efficiency In Rural Bangladesh: The Role Of Education Revisited, Mn Asadullah, S Rahman

School of Geography, Earth and Environmental Sciences

This article reassesses the debate over the role of education in farm production in Bangladesh using a large dataset on rice producing households from 141 villages. Average and stochastic production frontier functions are estimated to ascertain the effect of education on productivity and efficiency. A full set of proxies for farm education stock variables are incorporated to investigate the 'internal' as well as 'external' returns to education. The external effect is investigated in the context of rural neighbourhoods. Our analysis reveals that in addition to raising rice productivity and boosting potential output, household education significantly reduces production inefficiencies. However, we …

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Using Documents: A Figurational Approach, Paddy Dolan Jan 2009

Using Documents: A Figurational Approach, Paddy Dolan

Books/Book chapters

Notwithstanding significant changes in the research cultures of many social science disciplines, there remains a certain orthodoxy in the selection of qualitative methods for consumer research in particular. In this field, focus groups and depth (or qualitative) interviews reign supreme, while the use of documentary evidence is sparse. The obvious exception is the growing number of studies written by historians of consumer culture (see for example, Cohen, 2003; De Grazia, 2005; Donohue, 2006). Historians have traditionally used documents as evidence of particular events, values, ideas and practices at specific times and places. These events can then be organised into a …

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The Economic Determinants Of Crop Diversity On Farms In Rural Bangladesh, S Rahman Jan 2009

The Economic Determinants Of Crop Diversity On Farms In Rural Bangladesh, S Rahman

School of Geography, Earth and Environmental Sciences

The study examines the economic determinants of crop diversity using a survey of 406 farmers located in 21 villages in three agro-ecological regions of Bangladesh. The computed value of diversity indices of crop concentration (Herfindahl), richness (Margalef) and evenness (Shannon) confirm that farming system in Bangladesh is still relatively diverse despite four decades of thrust in the diffusion of a rice-based ‘Green Revolution’ technology. Results reveal that a host of price and non-price factors significantly influence farmers’ decision to diversify. Likelihood of diversification increases with a fall in the prices of fertilizers, animal power services and modern rice and a …

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Benthic Foraminifera Assemblages In The Central Barents Sea: An Evaluation Of Combining Live And Total Fauna Studies In Tracking Environmental Change, Mh Saher, Dk Kristensen, M Hald, S Korsun, Ll Jørgensen Jan 2009

Benthic Foraminifera Assemblages In The Central Barents Sea: An Evaluation Of Combining Live And Total Fauna Studies In Tracking Environmental Change, Mh Saher, Dk Kristensen, M Hald, S Korsun, Ll Jørgensen

School of Geography, Earth and Environmental Sciences

We present living (stained) benthic foraminifera assemblage data in nine surface sediment samples from the central Barents Sea collected in 2005 and 2006. The abundances of 20 selected species are compared to these from previously published total fauna assemblages of nearby samples. Between 1 and 3 total fauna samples from various years (between 1971 and 1992) are compared with the modern (2005 and ’06) samples. The main purpose of the paper is to evaluate the applicability of this comparison. We conclude that, with proper caution, comparing live and total fauna can yield valuable results. Eliminating fragile species, and clustering species …

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Out-Of-Plane Vibration Analysis With A Transmission Holographic Optical Element Based Electronic Speckle Pattern Interferometer, Viswanath Bavigadda, Vincent Toal, Raghavendra Jallapuram, Emilia Mihaylova Jan 2009

Out-Of-Plane Vibration Analysis With A Transmission Holographic Optical Element Based Electronic Speckle Pattern Interferometer, Viswanath Bavigadda, Vincent Toal, Raghavendra Jallapuram, Emilia Mihaylova

Conference Papers

A simple electronic speckle pattern interferometer (ESPI) using a transmission holographic optical element (THOE) is presented. The THOE is designed to create a speckled reference beam in the interferometer. It is a transmission hologram of a diffusely transmitting glass plate A specific requirement for the fabrication of the THOEs is for them to be recorded at one wavelength at which the recording material is photosensitive and reconstructed using a near infrared laser diode which can be current modulated for phase shifting purposes. A partially reflective glass plate provides illumination of the object along the normal to its surface, ensuring that …

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