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2007

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Reinventing A Level 7 Programme In Electrical Engineering And Greatly Improving On Student Retention, Eugene Coyle, Mike Murphy, Frank Costello, Leslie Shoemaker Jan 2007

Reinventing A Level 7 Programme In Electrical Engineering And Greatly Improving On Student Retention, Eugene Coyle, Mike Murphy, Frank Costello, Leslie Shoemaker

Books/Book chapters

Following the successful implementation over a number of decades of a three-year Diploma in Electrical and Control Engineering at Technological University Dublin, the programme entered a period of extreme difficulty and uncertainty in the late nineteen ninetees and early years of the new millennium. As with many such engineering programmes, student numbers seeking to enter began to diminish. Furthermore, engagement and retention of students who had enrolled on the programme became evermore challenging, necessitating some radical moves in the formation and operation of the programme and in putting additional student support mechanisms in place. The situation hit rock bottom between …

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Engineering Science As Opposed To Natural Science, Eugene Coyle, Mike Murphy, William Grimson Jan 2007

Engineering Science As Opposed To Natural Science, Eugene Coyle, Mike Murphy, William Grimson

Presentations

No abstract provided.

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Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn Jan 2007

Thermal Effectiveness Characteristics Of Low Approach Indirect Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Articles

Meteorological enthalpy analysis of temperate and maritime climates above latitude 45°N suggests that the water-side evaporative cooling technique has considerable unrealised potential with contemporary “high temperature” building cooling systems—such as chilled ceilings and displacement ventilation. As low approach conditions are the key to exploiting the cooling potential of the ambient air, thermal performance at such conditions needs to be investigated. To address the research issues, an industrial scale test rig, based on a low approach open cooling tower and plate heat exchanger and designed to maximise evaporative cooling potential, has been constructed. The thermal effectiveness of such systems (as a …

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Quantum Dot Energy Relaxation Mediated By Plasmon Emission In Doped Covalent Semiconductor Heterostructures, A. V. Fedorov, Anna Baranov, I. D. Rukhlenko, T. S. Perova, Kevin Berwick Jan 2007

Quantum Dot Energy Relaxation Mediated By Plasmon Emission In Doped Covalent Semiconductor Heterostructures, A. V. Fedorov, Anna Baranov, I. D. Rukhlenko, T. S. Perova, Kevin Berwick

Articles

The interaction between interface plasmons within a doped substrate and quantum dot electrons or holes has been theoretically studied in double heterostructures based on covalent semiconductors. The interface plasmon modes, the corresponding dispersion relationship, and the intraband carrier relaxation rate in quantum dots are reported. We find the critical points in the interface plasmon density of states for multilayered structures results in enhanced quantum dot intraband carrier relaxation when compared to that for a single heterostructure. A detailed discussion is made of the relaxation rate and the spectral position dependencies on the quantum dot layer thickness as well as on …

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The Sheffer Group And The Riordan Group, Tian-Xiao He, Peter Shiue, Leetsch Hsu Jan 2007

The Sheffer Group And The Riordan Group, Tian-Xiao He, Peter Shiue, Leetsch Hsu

Scholarship

We define the Sheffer group of all Sheffer-type polynomials and prove the isomorphism between the Sheffer group and the Riordan group. An equivalence of the Riordan array pair and generalized Stirling number pair is also presented. Finally, we discuss a higher dimensional extension of Riordan array pairs.

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Symbolization Of Generating Functions; An Application Of The Mullin–Rota Theory Of Binomial Enumeration, Tian-Xiao He, Peter S, Leetsch Hsu Jan 2007

Symbolization Of Generating Functions; An Application Of The Mullin–Rota Theory Of Binomial Enumeration, Tian-Xiao He, Peter S, Leetsch Hsu

Scholarship

We have found that there are more than a dozen classical generating functions that could be suitably symbolized to yield various symbolic sum formulas by employing the Mullin–Rota theory of binomial enumeration. Various special formulas and identities involving well-known number sequences or polynomial sequences are presented as illustrative examples. The convergence of the symbolic summations is discussed.

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Construction Of Biorthogonal B-Spline Type Wavelet Sequences With Certain Regularities, Tian-Xiao He Jan 2007

Construction Of Biorthogonal B-Spline Type Wavelet Sequences With Certain Regularities, Tian-Xiao He

Scholarship

No abstract provided.

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Two Number-Theoretic Problems That Illustrate The Power And Limitations Of Randomness, Andrew Shallue Jan 2007

Two Number-Theoretic Problems That Illustrate The Power And Limitations Of Randomness, Andrew Shallue

Scholarship

This thesis contains work on two problems in algorithmic number theory. The first problem is to give an algorithm that constructs a rational point on an elliptic curve over a finite field. A fast and easy randomized algorithm has existed for some time. We prove that in the case where the finite field has characteristic 2, there is a deterministic algorithm with the same asymptotic running time as the existing randomized algorithm.

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Thermal Control Of An Occupied Room: Investigating The Use Of Carbon Dioxide Concentration As An Auxiliary Control Variable, Kevin O'Connell, Aidan O'Dwyer Jan 2007

Thermal Control Of An Occupied Room: Investigating The Use Of Carbon Dioxide Concentration As An Auxiliary Control Variable, Kevin O'Connell, Aidan O'Dwyer

Conference papers

This paper details the theoretical and experimental work done in the examination of the relationship between human generated carbon dioxide concentration and temperature rise in an occupied room. Generation of carbon dioxide by humans is linked to metabolic rate and heat generation. Therefore, carbon dioxide concentration may be used as an indicator of occupancy in a room. Typically, a heating control system will react slowly to changes in room occupancy if temperature is used as the process variable. The aim of the work was to establish if carbon dioxide concentration in the space could be used as an auxiliary control …

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Transfer Function Modelling: A Student-Centred Learning Approach, Aidan O'Dwyer Jan 2007

Transfer Function Modelling: A Student-Centred Learning Approach, Aidan O'Dwyer

Conference papers

Traditionally, the modelling of real systems in engineering, using transfer functions, has been done in a mathematically intense manner. However, non-traditional learners such as mature students, part-time students and students without a conventional second-level educational background may not have strong mathematical foundations; in addition, all students increasingly expect technical work which is practical and which motivates independent learning. This paper reports on, reflects on and evaluates an innovative experiment developed by the author to estimate a transfer function model of a person’s eye-brain-hand motor response. In the experiment, carried out using a PC with data acquisition capability, the person is …

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Experiences With Virtual Learning Environments In Control Engineering Education, Aidan O'Dwyer Jan 2007

Experiences With Virtual Learning Environments In Control Engineering Education, Aidan O'Dwyer

Conference papers

The twin pressures of the need for students to learn a wider variety of concepts, ideally in a self-learning mode, and the reduction in class contact time has led to the use of increased levels of information technology in control engineering education. This paper reports on, reflects on, and evaluates the author’s use of virtual laboratories (computer based laboratories available on the internet) in control engineering modules at DIT Kevin St. The use of the virtual laboratories helps in the ongoing evolution of the teaching approach from a traditional didactic lecture and laboratory course to a more learner-centred approach. The …

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Stability Analysis And Control Synthesis Of Affine Fuzzy Systems, Ruiyao Gao, Aidan O'Dwyer Jan 2007

Stability Analysis And Control Synthesis Of Affine Fuzzy Systems, Ruiyao Gao, Aidan O'Dwyer

Conference papers

This paper presents an approach to stability analysis and control synthesis of affine fuzzy systems. The analysis is based on quadratic Lyapunov functions. The approach considers the nonlinear offset terms in affine fuzzy systems as non-vanishing perturbations added to the corresponding nominal linear blending systems. The affine fuzzy system is bounded by an ultimate limit if the corresponding linear blending system is exponentially stable. A state feedback controller with an extra term is designed with guaranteed global stability. The ultimate bounds are determined for both the open loop system and the compensated system.

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An Approach To Unification Using A Linear Systems Model For The Propagation Of Broad-Band Signals, Jonathan Blackledge Jan 2007

An Approach To Unification Using A Linear Systems Model For The Propagation Of Broad-Band Signals, Jonathan Blackledge

Articles

We review the inhomogeneous scalar Helmholtz equation in three-dimensions and the scattering of scalar wavefields from a scatterer of compact support. An asymptotic solution is then considered representing the effect of the frequency approaching zero when a ‘wavefield’ reduces to a ‘field’. The characteristics of ultra-low frequency Helmholtz scattering are then considered and the physical significance discussed of a model that is based on the scattering of Helmholtz wavefields over a broad frequency spectrum. This is equivalent to using a linear systems approach for modelling the propagation, interaction and detection of broad-band signals and provides an approach to the classification …

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Diffusion And Fractional Diffusion Based Models For Multiple Light Scattering And Image Analysis, Jonathan Blackledge Jan 2007

Diffusion And Fractional Diffusion Based Models For Multiple Light Scattering And Image Analysis, Jonathan Blackledge

Articles

This paper considers a fractional light diffusion model as an approach to characterizing the case when intermediate scattering processes are present, i.e. the scattering regime is neither strong nor weak. In order to introduce the basis for this approach, we revisit the elements of formal scattering theory and the classical diffusion problem in terms of solutions to the inhomogeneous wave and diffusion equations respectively. We then address the significance of these equations in terms of a random walk model for multiple scattering. This leads to the proposition of a fractional diffusion equation for modelling intermediate strength scattering that is based …

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Engineering Science As Opposed To Natural And Applied Science, Eugene Coyle, Mike Murphy, William Grimson Jan 2007

Engineering Science As Opposed To Natural And Applied Science, Eugene Coyle, Mike Murphy, William Grimson

Books/Book chapters

In exploring the epistemology of engineering science we propose a model of engineering. This model incorporates the goals of engineering, the approach to engineering (also called the engineering method) and the role of experience in engi-neering. The basis for understanding the nature of engineering science will be ex-plored, and will be contrasted with natural science. To begin, a large-scale engi-neering project that was successfully completed in Ireland many years ago is dis-cussed - specifically, the development of a megalithic passage tomb as an exemplar of the engineering method in structural design, project management and aesthetics. This exemplar firmly demonstrates that …

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Engineering - An Inherently Philosophical Enterprise, William Grimson Jan 2007

Engineering - An Inherently Philosophical Enterprise, William Grimson

Books/Book chapters

No abstract provided.

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From Certificates To Doctorates, By Degrees: Dublin Institute Of Technology - A Photographic Memoir, Jimmie Robinson Jan 2007

From Certificates To Doctorates, By Degrees: Dublin Institute Of Technology - A Photographic Memoir, Jimmie Robinson

Books

Jimmie Robinson has photographed visitors and events at Dublin Institute of Technology for 43 years. In this photographic memoir, he chronicles the development of DIT over its first 120 years from behind the lens.

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Evolution Of Prehension Ability In An Anthropomorphic Neurorobotic Arm, G Massera Jan 2007

Evolution Of Prehension Ability In An Anthropomorphic Neurorobotic Arm, G Massera

School of Engineering, Computing and Mathematics

In this paper, we show how a simulated anthropomorphic robotic arm controlled by an artificial neural network can develop effective reaching and grasping behaviour through a trial and error process in which the free parameters encode the control rules which regulate the fine-grained interaction between the robot and the environment and variations of the free parameters are retained or discarded on the basis of their effects at the level of the global behaviour exhibited by the robot situated in the environment. The obtained results demonstrate how the proposed methodology allows the robot to produce effective behaviours thanks to its ability …

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Behavioural Syndromes In Brook Charr, Salvelinus Fontinalis: Prey-Search In The Field Corresponds With Space Use In Novel Laboratory Situations, Alexander D.M. Wilson, Robert L. Mclaughlin Jan 2007

Behavioural Syndromes In Brook Charr, Salvelinus Fontinalis: Prey-Search In The Field Corresponds With Space Use In Novel Laboratory Situations, Alexander D.M. Wilson, Robert L. Mclaughlin

School of Biological and Marine Sciences

No abstract provided.

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Analysis Of Supercritical Stratified Tidal Flow In A Scottish Fjord, Nataliya Stashchuk, Mark Inali, Vasiliy Vlasenko Jan 2007

Analysis Of Supercritical Stratified Tidal Flow In A Scottish Fjord, Nataliya Stashchuk, Mark Inali, Vasiliy Vlasenko

School of Biological and Marine Sciences

The baroclinic tidal regime of the fjord Loch Etive (Scotland) is studied. Analysis is performed on the basis of both in situ data and numerical simulations, with the use of a fully nonlinear nonhydrostatic fine-resolution model. It was found that the crest of the sill that separates Loch Etive into inner and outer parts is subjected to a supercritical flow regime with maximum Froude numbers in excess of 5. Strong supercritical conditions lead to the formation of flow separation just above the sill's crest. As is inherent to jet-type fjordic systems, this, in turn, leads to a weak nonlinear baroclinic …

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Hologram-Based Humidity Indicator For Domestic And Packaging Applications, Izabela Naydenova, Raghavendra Jallapuram, Vincent Toal, Suzanne Martin Jan 2007

Hologram-Based Humidity Indicator For Domestic And Packaging Applications, Izabela Naydenova, Raghavendra Jallapuram, Vincent Toal, Suzanne Martin

Conference Papers

A passive indicator for Relative Humidity based on a photopolymer recorded hologram has been developed. The indicator works on the principle that the wavelength reconstructed by a reflection hologram is dependent on the spacing between the fringe planes of the hologram. As the Relative Humidity changes, the hologram swells or shrinks and the apparent colour of the reconstructed image changes. The response time, operational range and reversibility of the indicator have been studied in a controlled humidity environment. Response times from less than a minute to tens of minutes depending on the holograms physical properties have been measured. Indicators with …

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A Study Of Linear Error Correcting Codes, Cen Jung Tjhai Jan 2007

A Study Of Linear Error Correcting Codes, Cen Jung Tjhai

School of Engineering, Computing and Mathematics Theses

Since Shannon's ground-breaking work in 1948, there have been two main development streams of channel coding in approaching the limit of communication channels, namely classical coding theory which aims at designing codes with large minimum Hamming distance and probabilistic coding which places the emphasis on low complexity probabilistic decoding using long codes built from simple constituent codes. This work presents some further investigations in these two channel coding development streams. Low-density parity-check (LDPC) codes form a class of capacity-approaching codes with sparse parity-check matrix and low-complexity decoder Two novel methods of constructing algebraic binary LDPC codes are presented. These methods …

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Improving The Prediction Of The Behaviour Of Masonry Wall Panels Using Model Updating And Artificial Intelligence Techniques, Chengfei Sui Jan 2007

Improving The Prediction Of The Behaviour Of Masonry Wall Panels Using Model Updating And Artificial Intelligence Techniques, Chengfei Sui

School of Engineering, Computing and Mathematics Theses

Out-of-plane laterally loaded masonry wall panels are still much used in modem structures. However due to their anisotropic and highly composite nature, it is extremely difficult to understand their behaviour and to date there is no analytical method that is capable of accurately predicting the response of masonry panels to the applied loadings. This is one of the major obstacles in analysing and designing masonry structures. This research studied a new method that accurately predicts the response of laterally loaded masonry wall panels. In this dissertation, the method of using corrector factors developed by previous researchers was further studied using …

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The Strategic Use Of Geographic Information Systems In The Irish Insurance Industry, Stephen Willis Jan 2007

The Strategic Use Of Geographic Information Systems In The Irish Insurance Industry, Stephen Willis

Masters

The motivation for the research arose from the significant increase in flooding events that have occurred in Ireland and other countries over the last decade. These floods can cause major damage to properties and have resulted in significant losses for insurance companies. There was an expression of interest from within the Irish insurance industry to utilise Geographic Information Systems (GIS) for enhancing the value of their customer data and with the recent losses they began considering using GIS for mapping flood prone areas. Anecdotal evidence suggested that the availability of accurate, up to date and relevant data to support a …

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Software Architecture For Data Storage Concepts Within Future Mobile Telecommunication Systems, Andreas Diehl Jan 2007

Software Architecture For Data Storage Concepts Within Future Mobile Telecommunication Systems, Andreas Diehl

School of Engineering, Computing and Mathematics Theses

In current mobile telecommunication networks, databases and the subscriber data is distributed among multiple network domains and database systems. The heterogeneous data storage concept is based on the permanent evolution of the mobile networks and the support of different kinds of network technologies. Dependent on the particular network domain and the dedicated technology, distributed subscriber data has to be accessed via specialised protocols.This thesis proposes a novel software architecture for the next generation profile register (NGPR) - an approach to provide subscriber information using a logically centralised register for subscriber data from several mobile network domains. The NGPR subscriber data …

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Statistical Contributions To Medical Research In The South West Peninsula, Hilary Patricia Sanders Jan 2007

Statistical Contributions To Medical Research In The South West Peninsula, Hilary Patricia Sanders

School of Engineering, Computing and Mathematics Theses

The papers on which this thesis is based are the result of original research work undertaken in collaboration with healthcare researchers in the South West Peninsula. Modern healthcare research involves large scale multidisciplinary projects and the Statistician's role In these projects, from concept through design and execution to the production of published papers, is crucial. Funding bodies, and in particular the Medical Research Council (MRC), expect a Statistician to be part of the project team and the statistical input and expertise included plays a key role in determining whether or not projects are funded and are subsequently successful. The selection …

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Modelling Of Re-Absorption Losses In Quantum Dot Solar Concentrators, Manus Kennedy Jan 2007

Modelling Of Re-Absorption Losses In Quantum Dot Solar Concentrators, Manus Kennedy

Conference Papers

A Monte-Carlo ray-trace model has been developed which allows the calculation of the optical efficiency (ηopt) and concentration ratio (CR) values of a Quantum Dot Solar Concentrator (QDSC). In this paper, ηopt values have been calculated using a range of material refractive indices, material attenuation coefficients, and quantum dot (QD) quantum efficiencies (QE). Spectral overlap leads to reabsorption of light in the device which leads to increased escape cone losses and QD QE losses. Results have been obtained for ideal QD spectra, where there is 0% overlap between QD emission and absorption spectra (and hence no re-absorption), and for real …

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What Now?: Evaluating Elearning Cpd Practice In Irish Third-Level Education, Roisin Donnelly, K. C. O'Rourke Jan 2007

What Now?: Evaluating Elearning Cpd Practice In Irish Third-Level Education, Roisin Donnelly, K. C. O'Rourke

Journal Articles

The internet has made it impossible for higher education institutions to ignore technology in fulfilling their strategic mission and respond to the expectations of a diverse student body. In the Republic of Ireland, as elsewhere, the use of online technologies has become an increasingly important challenge in academic staff development, and on the surface, eLearning has been moderately successful in the teaching and learning environment. However, given the rapid rate of change in both technology and the increasing diversity in academic staff and students, to describe accurately the nature of eLearning for academic staff development is near impossible. There has …

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Characteristics Of Cooked Chickpeas And Soybeans During Combined Microwave–Convective Hot Air Drying, Aoife Gowen, Nissreen Abu-Ghannam, Jesus Maria Frias, Jorge Oliveira Jan 2007

Characteristics Of Cooked Chickpeas And Soybeans During Combined Microwave–Convective Hot Air Drying, Aoife Gowen, Nissreen Abu-Ghannam, Jesus Maria Frias, Jorge Oliveira

Articles

Moisture content, shrinkage, water activity (Aw), color and texture of cooked chickpeas and soybeans during convective, microwave and combined microwave–convective drying were studied. Combined drying was significantly (P < 0.05) faster than either convective or microwave drying, and resulted in less shrinkage of the dehydrated product. Rapid burning occurred when samples were dried below a Aw of 0.27 ± 0.07 for chickpeas (P < 0.05), and 0.13 ± 0.04 for soybeans (P < 0.05). Both chickpeas and soybeans displayed a transitional behavior in texture when dried to a Aw below 0.40 ± 0.10 (P < 0.05) for chickpeas, and below 0.63 ± 0.15 (P < 0.05) for soybeans, when samples became brittle. Shelf stable dehydrated chickpea and soybean products with low water activity (Aw = 0.35) and good visual quality could be obtained within 14 min of combination drying.

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Simultaneous Modelling Of The Thermal Degradationa Kinetics Of Pectin, Daniel Rico, Ana Belen Martin-Diana, Catherine Barry-Ryan, Gary Henehan, Jesus Maria Frias Jan 2007

Simultaneous Modelling Of The Thermal Degradationa Kinetics Of Pectin, Daniel Rico, Ana Belen Martin-Diana, Catherine Barry-Ryan, Gary Henehan, Jesus Maria Frias

Articles

The thermal degradation kinetics of pectin methylesterase (PME) from carrot and lettuce were studied. Fresh extracts were exposed to temperatures from 55 to 70 °C until the enzyme was inactivated. A model based on the presence of two forms of the enzyme, one active and one non-active, is proposed. The natural variability of the PME activity was taken into the model in the form of normally distributed random effects. The common model parameters obtained (cleavage constant (0.0395±0.0062 s−1), degradation constant (0.556±0.112 s−1), cleavage energy of activation (469±23 kJ mol−1) and degradation energy of activation …

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