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2010

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Articles 4171 - 4200 of 5375

Full-Text Articles in Engineering

Solar Cell Efficiency Enhancement Through Down-Shifting And Up-Converting Layers: The Ephocell Project: Luminescent Downshifting Quantum Yield Measurements, M. Kennedy, L. Aubouy, D. Gutiérrez-Tauste, A. Jorge, M. Faccini, G. Noriega, M. Di Lorenzo, M. Cocca, M. Avella, M. Errico, G. Gentile, John Doran, Brian Norton, S. Baluschev, J. Bistué Guardiola, A. Robles Molina, J. Puigdollers, C. Voz, S. Daren, F. Tsvetkov, A. Pashov Jan 2010

Solar Cell Efficiency Enhancement Through Down-Shifting And Up-Converting Layers: The Ephocell Project: Luminescent Downshifting Quantum Yield Measurements, M. Kennedy, L. Aubouy, D. Gutiérrez-Tauste, A. Jorge, M. Faccini, G. Noriega, M. Di Lorenzo, M. Cocca, M. Avella, M. Errico, G. Gentile, John Doran, Brian Norton, S. Baluschev, J. Bistué Guardiola, A. Robles Molina, J. Puigdollers, C. Voz, S. Daren, F. Tsvetkov, A. Pashov

Conference Papers

Organic cells and dye-sensitized cells developed to-date have a narrow active absorption range, relative to the spectral range of the available solar resource. Their efficiency could be significantly enhanced through a process of down-shifting (DS) and up-conversion of non-absorbable photons converting them to photons better matching the spectral response of the particular solar cell. The DS molecules must exhibit a large Stokes shift and high luminescent quantum yield when incorporated in the downshifting polymer layer. In this paper, the QY of a downshifting Europium (III) complex in solution is determined using two distinct experimental techniques. The QY is measured for …


Estimation Of 3d Shape In The Patellofemoral Joint Using Statistical Shape Models And 2d Data, Colm O'Kane Jan 2010

Estimation Of 3d Shape In The Patellofemoral Joint Using Statistical Shape Models And 2d Data, Colm O'Kane

Conference Papers

Disorders of the patellofemoral joint (PFJ) including PF osteoarthritis and PF pain disorder have been estimated to represent 25% of all patients presenting for knee joint treatment. The diagnosis and treatment of these disorders is curtailed by lack of understanding of the mechanical operation of the joint. A crucial aspect to be considered in understanding contact patterns and kinematics of the PFJ is the alignment of the patella in the trochlear groove. Investigation of patellar alignment necessitates accurate knowledge of the 3D articular surfaces of both patella and femur, along with underlying bone geometry. These 3D data are generally obtained …


Applying Geographic Information Systems To Support Strategic Environmental Assessment: Opportunities And Limitations In The Context Of Irish Land-Use Plans, Ainhoa Gonzalez, Alan Gilmer, Ronan Foley, John Sweeney, John Fry Jan 2010

Applying Geographic Information Systems To Support Strategic Environmental Assessment: Opportunities And Limitations In The Context Of Irish Land-Use Plans, Ainhoa Gonzalez, Alan Gilmer, Ronan Foley, John Sweeney, John Fry

Articles

The strengthening of spatial database infrastructures, further promoted by the INSPIRE Directive adopted in 2007, has led to an increased use of spatial data in planning and decision-making. Given that land-use plans are intrinsically spatial, such evidence and approaches can significantly benefit plan-making. A spatial framework could especially support the specific Strategic Environmental Assessment (SEA) aspects of the plan-making process. Spatial tools such as Geographic Information Systems (GIS) are particularly well-placed to support the environmental integration sought in SEA by providing evidence through the spatial assessment of multiple environmental datasets. Moreover, GIS bring the opportunity to augment conventional assessment techniques …


Bent Sms Fiber Structure For Temperature Measurement, Qiang Wu, Yuliya Semenova, Agus Hatta, Pengfei Wang, Gerald Farrell Jan 2010

Bent Sms Fiber Structure For Temperature Measurement, Qiang Wu, Yuliya Semenova, Agus Hatta, Pengfei Wang, Gerald Farrell

Articles

We have proposed a temperature sensor fabricated using a bent SMS fiber structure. Our experimental results show, that by comparison to a sensor based on a straight SMS fiber structure, this temperature sensor has a much higher sensitivity of 31.97 pm/°C over a temperature range from 20 to 80 °C based on the measurement of the mean 3 dB wavelength shift and offers a resolution of 0.1 °C for temperature range from 45 to 80 °C when demodulated by a simple ratiometric interrogation technique.


Temperature Performance Of A Macrobending Single-Mode Fiber-Based Refractometer, Pengfei Wang, Yuliya Semenova, Qiang Wu, Zie Zheng, Gerald Farrell Jan 2010

Temperature Performance Of A Macrobending Single-Mode Fiber-Based Refractometer, Pengfei Wang, Yuliya Semenova, Qiang Wu, Zie Zheng, Gerald Farrell

Articles

The temperature dependence of polarization-dependent loss (PDL) for a macrobending standard single-mode fiber (SMF28) is investigated both theoretically and experimentally. The experimental results show an overall agreement with the proposed theoretical model over a temperature range from 0 C to 70 C. An SMF28-based edge filter is used as an example regarding temperature- dependent PDL performance. It is shown that the temperature variations have a significant influence on the polarization dependence of macrobending loss, and further impact on such a fiber bend loss edge filter used in a wavelength measurement application. It is also concluded that by using the proposed …


A Liquid Crystal Coated Tapered Photonic Crystal Fiber Interferometer, Ginu Rajan, Sunish Mathews, Gerald Farrell, Yuliya Semenova Jan 2010

A Liquid Crystal Coated Tapered Photonic Crystal Fiber Interferometer, Ginu Rajan, Sunish Mathews, Gerald Farrell, Yuliya Semenova

Articles

An experimental investigation on liquid crystal coated tapered photonic crystal fiber (PCF) interferometer is presented in this paper. The interferometer is fabricated by tapering a small section of a PCF by collapsing the air holes and thinning down the air hole collapsed region to a micron size. Several interferometers are fabricated from different types of photonic crystal fibers and the temperature dependence studies are carried out to select an intrinsically temperature insensitive interferometer that can be used with liquid crystal (LC) materials. The properties of the LC materials to be used with the tapered PCF interferometers are also discussed. Temperature …


Experimental Analysis And Demonstration Of A Low Cost Fibre Optic Temperature Sensor System For Engineering Applications, Ginu Rajan, Yuliya Semenova, Jinesh Mathew, Gerald Farrell Jan 2010

Experimental Analysis And Demonstration Of A Low Cost Fibre Optic Temperature Sensor System For Engineering Applications, Ginu Rajan, Yuliya Semenova, Jinesh Mathew, Gerald Farrell

Articles

An epoxy packaged surface mountable fibre temperature sensor for engineering applications is presented in this paper. The temperature sensor is based on a macro-bend single-mode fibre loop employed in a ratiometric power measurement scheme and has a linear characteristic with temperature at a fixed wavelength and bend radius. The sensor head consists of a single turn of a bare bend sensitive single-mode fibre with an applied absorption coating. The temperature of the sensor head is varied up to 80 0C and the linearity of the response is studied with different applied absorption coatings. The sensor head is packaged in a …


Simulation Optimisation Methods In Supply Chain Applications: A Review, Amr Arisha, Waleed Abo-Hamad Jan 2010

Simulation Optimisation Methods In Supply Chain Applications: A Review, Amr Arisha, Waleed Abo-Hamad

Articles

The competitiveness and dynamic nature of today’s marketplace is due to rapid advances in information technology, short product life cycles and the continuing trend in global outsourcing. Managing the resulting supply chain networks effectively is challenged by high levels of uncertainty in supply and demand, confl ict objectives, vagueness of information, numerous decision variables and constraints. With such levels of complexity, supply chain optimisation has the potential to make a signifi cant contribution in resolving these challenges. In this paper, a literature review – based on more than 100 peer-reviewed articles – of state-of-the-art simulation-based optimisation techniques in the context …


Broadening Ethics Teaching In Engineering: Beyond The Individualistic Approach, Eddie Conlon, H. Zandvoort Jan 2010

Broadening Ethics Teaching In Engineering: Beyond The Individualistic Approach, Eddie Conlon, H. Zandvoort

Articles

There is a widespread approach to the teaching of ethics to engineering students in which the exclusive focus is on engineers as individual agents and the broader context in which they do their work is ignored. Although this approach has frequently been criticised in the literature, it persists on a wide scale, as can be inferred from accounts in the educational literature and from the contents of widely used textbooks in engineering ethics. In this contribution we intend to: (1) Restate why the individualistic approach to the teaching of ethics to engineering students is inadequate in view of preparing them …


The Role Of Sustainability In Scm: The Case Of The Sustainable Packaging Supply Chain, Edward Sweeney Jan 2010

The Role Of Sustainability In Scm: The Case Of The Sustainable Packaging Supply Chain, Edward Sweeney

Practitioner Journals

No abstract provided.


An Investigation Of Semantic Links To Archetypes In An External Clinical Terminology Through The Construction Of Terminological "Shadows", Sheng Yu, Damon Berry, Jesús Bisbal Jan 2010

An Investigation Of Semantic Links To Archetypes In An External Clinical Terminology Through The Construction Of Terminological "Shadows", Sheng Yu, Damon Berry, Jesús Bisbal

Conference Papers

The two-level model based specifications for electronic health record communication EHRcom (ISO 13606) and openEHR both support the embedding of terminological references in Archetypes. This terminological binding can be created manually by a health terminology expert during Archetype design, and the binding is assessed during Archetype evaluation. There has also been some recent work on using lexical queries to generate term sets to represent concepts in Archetypes. This work created an information construct which we call a Terminological Shadow that links Archetype nodes to sets of candidate concepts from a terminology system. The coding scheme used for this work is …


An Approach Based On Particle Swarm Computation To Study The Nanoscale Dg Mosfet-Based Circuits, Fayacl Djeffal, Toufik Bendib, Redha Benzid, Abdelhamid Benhaya Jan 2010

An Approach Based On Particle Swarm Computation To Study The Nanoscale Dg Mosfet-Based Circuits, Fayacl Djeffal, Toufik Bendib, Redha Benzid, Abdelhamid Benhaya

Turkish Journal of Electrical Engineering and Computer Sciences

The analytical modeling of nanoscale Double-Gate MOSFETs (DG) requires generally several necessary simplifying assumptions to lead to compact expressions of current-voltage characteristics for nanoscale CMOS circuits design. Further, progress in the development, design and optimization of nanoscale devices necessarily require new theory and modeling tools in order to improve the accuracy and the computational time of circuits' simulators. In this paper, we propose a new particle swarm strategy to study the nanoscale CMOS circuits. The latter is based on the 2-D numerical Non-Equilibrium Green's Function (NEGF) simulation and a new extended long channel DG MOSFET compact model. Good agreement between …


Estimating The Characteristic Vertical Response Of A Flexible Footbridge Due To Crowd Loading, Joe Keogh, Colin C. Caprani, Paul Archbold, Paul Fanning Jan 2010

Estimating The Characteristic Vertical Response Of A Flexible Footbridge Due To Crowd Loading, Joe Keogh, Colin C. Caprani, Paul Archbold, Paul Fanning

Conference papers

The issue of excessive vibration of footbridges due to pedestrian loading is now well documented. Bridge vibrations produced from a crowd of pedestrians have been estimated by modifying the effect caused by a single pedestrian by an enhancement factor to take crowd synchronization into account. In this paper this approach is extended to account for the fact that all pedestrians will not have the same pacing frequencies, and the effects of distributions of pacing frequency and other parameters on the enhancement factor are investigated. It is shown that this more faithful representation of pedestrian crowd walking behaviour gives reduced vibration …


A New Congested Traffic Load Model For Highway Bridges, Colin C. Caprani, Colm Carey, Bernard Enright Jan 2010

A New Congested Traffic Load Model For Highway Bridges, Colin C. Caprani, Colm Carey, Bernard Enright

Conference papers

Long span highway bridges are critical components of any nation’s infrastructure. Therefore accurate assessment of highway bridge loading is essential, and it is well known that congested traffic governs load effect for such bridges. Current congestion models use conservative assumptions about traffic and inter-vehicle gaps. This research investigates congested traffic flow through the use of traffic microsimulation which has the ability to reproduce complex traffic phenomena based on driver interactions. A time series model has been developed to produce a speed time-series similar to the results of the microsimulation. The speed time-series from the new model, combined with the established …


The Influence Of Correlation On The Extreme Traffic Loading Of Bridges, Eugene J. Obrien, Bernard Enright, A. T. Dempsey Jan 2010

The Influence Of Correlation On The Extreme Traffic Loading Of Bridges, Eugene J. Obrien, Bernard Enright, A. T. Dempsey

Conference papers

Accurate traffic loading models based on measured data are essential for the accurate assessment of existing bridges. There are well-established methods for the Monte Carlo simulation of single lanes of traffic, and this can easily be extended to model the loading on bridges with two independent streams of traffic in opposing directions. However, a typical highway bridge will have multiple lanes in the same direction, and various types of correlation are evident in measured traffic. This paper analyses traffic patterns using multi-lane WIM data collected at two European sites. It describes an approach to the Monte Carlo simulation of this …


Management Strategies For Special Permit Vehicles For Bridge Loading, Bernard Enright, Eugene J. Obrien Jan 2010

Management Strategies For Special Permit Vehicles For Bridge Loading, Bernard Enright, Eugene J. Obrien

Conference papers

An examination of weigh-in-motion data collected recently at sites in five European countries has shown that vehicles with weights well in excess of the normal legal limits are found on a daily basis. These vehicles would be expected to have permits issued by the responsible authorities. It can be seen from the measurements that most of them are travelling at normal speeds. Photographic evidence indicates that, while many are accompanied by an escort vehicle, normal traffic is flowing alongside in other lanes. As European freight volume grows, the frequency of these special vehicles can be expected to increase. Hence, the …


Speech Intelligibility From Image Processing, Andrew Hines, Naomi Harte Jan 2010

Speech Intelligibility From Image Processing, Andrew Hines, Naomi Harte

Articles

Hearing loss research has traditionally been based on perceptual criteria, speech intelligibility and threshold levels. The development of computational models of the auditory-periphery has allowed experimentation via simulation to provide quantitative, repeatable results at a more granular level than would be practical with clinical research on human subjects.


Simulation Algorithm And Validation Of A Photovoltaic Water Pumping System, I. Odeh, Y. Yohannis, Brian Norton Jan 2010

Simulation Algorithm And Validation Of A Photovoltaic Water Pumping System, I. Odeh, Y. Yohannis, Brian Norton

Articles

A photovoltaic (PV) water pumping system has been modelled using TRNSYS considering a power supply, a direct current (DC)/alternating current (AC) inverter, an AC induction motor, a centrifugal pump, a well, a water storage tank, and an overflow protection device. The model emulates actual pumping head curves, uses numerical methods to determine pump system working points, and includes a storage tank as a component in the system. It simulates PV-powered water pumping systems, constant voltage tracking, voltage frequency modulation, and maximum power point tracking algorithms; variable inverter frequency with variable motor efficiency, variable inverter frequency with constant motor efficiency, and …


Simulation Procedure For The Co-Optimization Of Photovoltaic Water Pumping Systems., Brian Norton Jan 2010

Simulation Procedure For The Co-Optimization Of Photovoltaic Water Pumping Systems., Brian Norton

Articles

Abstract: Photovoltaic (PV)-powered centrifugal water pumping systems have been modelled based on field experience and analysis of long-term measured performance of several installed PV-powered water pumping systems. This paper presents detailed modelling of a PV array, an inverter, a three-phase induction motor, a centrifugal pump, a well, a storage tank, an overflow controller, and an integrated reverse osmosis desalination unit. The component models were validated using both laboratory measurements and long-term monitored data. All system components have been modelled separately, and the system was modelled in TRNSYS. The models are capable of simulating grid-connected, diesel-powered, and PV-powered water pumping systems, …


Building Support For Coud Computing In The Irish Construction Industry, Alan Redmond, Alan V. Hore, Roger West Jan 2010

Building Support For Coud Computing In The Irish Construction Industry, Alan Redmond, Alan V. Hore, Roger West

Conference papers

The construction industry has been traditionally recognised as a fragmented sector associated with a poor level of implementation and penetration of Information Communication Technology (ICT) by Small to Medium Size Enterprises (SMEs). Cloud computing is a collective term that can facilitate the ability to collaborate within a central repository that can act as a base for interoperability between various construction disciplines and their software applications. Cloud computing is a new layer of internet architecture that creates an open opportunity to add better functionality to an increasingly global network. The characteristics of cloud computing, such as, shared infrastructure, on-demand applications, elasticity …


Developing A Cloud Integrated Life Cycle Costing Analysis Model Through Bim, Alan Redmond, Alan V. Hore, Roger West Jan 2010

Developing A Cloud Integrated Life Cycle Costing Analysis Model Through Bim, Alan Redmond, Alan V. Hore, Roger West

Conference papers

Advancing interoperability between design team applications has been a major challenge for advocates of open standards. The buildingSmart alliance and Open Geospatial Consortium Inc in the U.S. have developed and implemented an Architecture, Engineering, Construction, Owner Operator, Phase 1 Testbed that streamlines communications between parties at the conceptual design phase to establish an early understanding of the tradeoffs between construction cost and energy efficiency. The results of this Testbed combined with an on-going collaborative R&D project ‘Inpro’ co-funded by the European Commission to identify business and legal issues of Building Information Modeling in construction were used as theoretical propositions underlying …


Apartment Living And The Multi-Unit Developments Bill 2009, Lorcan Sirr Jan 2010

Apartment Living And The Multi-Unit Developments Bill 2009, Lorcan Sirr

Articles

No abstract provided.


There's More To Planning Than Coloured Maps, Lorcan Sirr Jan 2010

There's More To Planning Than Coloured Maps, Lorcan Sirr

Articles

No abstract provided.


Spontaneous Periodic Deformations In Nonchiral Planar-Aligned Bimesogens With A Nematic-Nematic Transition And A Negative Elastic Constant, V. P. Panov, J. K. Vij, Yuri Panarin, A. Kohlmeier, M. G. Tamba, R. A. Lewis, G. H. Mehl Jan 2010

Spontaneous Periodic Deformations In Nonchiral Planar-Aligned Bimesogens With A Nematic-Nematic Transition And A Negative Elastic Constant, V. P. Panov, J. K. Vij, Yuri Panarin, A. Kohlmeier, M. G. Tamba, R. A. Lewis, G. H. Mehl

Articles

Hydrocarbon linked mesogenic dimers are found to exhibit an additional nematic phase below the conventional uniaxial nematic phase as confirmed by x-ray diffraction. The phase produces unusual periodic stripe domains in planar cells. The stripes are found to be parallel to the rubbing direction (in rubbed cells) with a well-defined period equal to double the cell gap. The stripes appear without external electromagnetic field, temperature or thickness gradients, rubbing or hybrid alignment treatments. Simple modeling proposes a negative sign for at least one of the two elastic constants: splay and twist, as a necessary condition for the observed pattern.


Interactive Music Archive Access System, Martin Gallagher, Derry Fitzgerald, Dan Barry, Matt Cranitch, Eugene Coyle Jan 2010

Interactive Music Archive Access System, Martin Gallagher, Derry Fitzgerald, Dan Barry, Matt Cranitch, Eugene Coyle

Conference papers

The goal of the Interactive Music Archive Access System (IMAAS) project was to develop an interactive music archive access system which was capable of allowing an end-user to easily extract rhythmic, melodic and harmonic musical metadata descriptors from audio, and allow the user to interact with the archive contents in a manner not typically allowed in archive access systems. To this end, the IMAAS system incorporates a range of real-time interaction tools which allow the user to modify the retrieved audio in a number of ways including the ability to isolate individual instruments in stereo mixes, pitch and time-scale modification, …


Locating Tune Changes And Providing A Semantic Labelling Of Sets Of Irish Traditional Tunes, Cillian Kelly, Mikel Gainza, David Dorran, Eugene Coyle Jan 2010

Locating Tune Changes And Providing A Semantic Labelling Of Sets Of Irish Traditional Tunes, Cillian Kelly, Mikel Gainza, David Dorran, Eugene Coyle

Conference papers

An approach is presented which provides the tune change loactions within a set of Irish traditional turnes. Also provided are semantic labels for each part of each tune within the set. A set in Irish traditional music is a number of individual tunes played segue. Each of the tunes in the set are made up of structural segments called parts. Musical variation is a prominent characteristic of this genre. However, a certain set of notes known as "set accented tones" are considered impervious to musical variation. Chroma information is extracted at "set accented tone" locations within the music. The resulting …


Audio Thumbnail Generation Of Irish Traditional Music, Cillian Kelly, Mikel Gainza, David Dorran, Eugene Coyle Jan 2010

Audio Thumbnail Generation Of Irish Traditional Music, Cillian Kelly, Mikel Gainza, David Dorran, Eugene Coyle

Conference papers

An approach is presented which generates an audio thumbnail of Irish traditional music. An audio thumbnail is consered to be the most representative segment of the music. For popular music, the chorus is considered to be an ideal audio thumbnail, however in Irish Traditional Music there is no chorus. An Irish Traditional tune consists of tow or mor short structural segments called parts. Parts are repeated to extend the tuen, and the tune itself is also repeated once or more in its entirety. To further extend a performance, tunes are concatenated to form a set of tuens. As a result, …


On The Appearance Of A Positive Real Pole In The Results Of Glottal Closed Phase Linear Prediction, Alan O'Cinneide, David Dorran, Mikel Gainza, Eugene Coyle Jan 2010

On The Appearance Of A Positive Real Pole In The Results Of Glottal Closed Phase Linear Prediction, Alan O'Cinneide, David Dorran, Mikel Gainza, Eugene Coyle

Conference papers

Often when performing glottal closed phase covariance linear prediction, a positive real pole can appear in the resulting filter transfer function. The commonly adopted approach is to discard this pole, as it does not fit with the usual model of the all-pole vocal tract filter. However, this real pole describes some aspect of the speech signal; this paper provides a novel perspective on its occurrence. This viewpoint has a useful implication to the speech community, especially from the perspective of fitting a glottal pulse to the inverse filtered signal, as the real pole describes the return phase of the glottal …


Towards A Method To Determine The Glottal Formant Parameters Of Voiced Speech Without Time-Domain Reference, Alan O'Cinneide, David Dorran, Mikel Gainza, Eugene Coyle Jan 2010

Towards A Method To Determine The Glottal Formant Parameters Of Voiced Speech Without Time-Domain Reference, Alan O'Cinneide, David Dorran, Mikel Gainza, Eugene Coyle

Conference papers

This paper presents an approach to estimate the glottal formant parameters of the voicing source in the frequency-domain. The method is based on a simplified pole-zero interpretion of the prevalent Liljencrants-Fant (LF) model of glottal flow, and gives approximations for a broad range of pulses shapes. An advantage of the method is that, unlike other methods, it does not rely on time-domain references.


Harmonic/Percussive Separation Using Median Filtering, Derry Fitzgerald Jan 2010

Harmonic/Percussive Separation Using Median Filtering, Derry Fitzgerald

Conference papers

In this paper, we present a fast, simple and effective method to separate the harmonic and percussive parts of a monaural audio signal.The technique involves the use of median filtering on a spectrogram of the audio signal, with median filtering performed across successive frames to suppress percussive events and enhance harmonic components, while median filtering is also performed across frequency bins to enhance percussive events and supress harmonic components. The two resulting median filtered spectrograms are then used to generate masks which are then applied to the original spectrogram to separate the harmonic and percussive parts of the signal. We …