Engineering Commons^™

Photopolymer Diffractive Optical Elements In Electronic Speckle Pattern Shearing Interferometry, Emilia Mihaylova, Izabela Naydenova, Barry Duignan, Suzanne Martin, Vincent Toal

Articles

In this paper we present an electronic speckle pattern shearing interferometer using a photopolymer diffractive optical element in the form of a holographic grating, in combination with a ground glass to shear the images. The sheared images on the ground glass are further imaged onto a CCD camera. The distance between the grating and the ground glass can be used to control the shear and to vary the sensitivity of the system. The direction of sensitivity is easily controlled by rotation of the diffraction grating around its normal. Introducing photopolymer holographic gratings in ESPSI gives the advantage of using high …

An Approach To Teaching Pid Controller Tuning, Aidan O'Dwyer

Conference papers

This paper discusses an approach to the teaching of PID controller tuning methods to students in control engineering at Dublin Institute of Technology. The method involves analytically calculating the gain margin, phase margin and maximum sensitivity for PI and PID controlled systems whose process is modelled in first order lag plus time delay (FOLPD) form. Students can examine the performance of many tuning rules from graphical results, allowing insight to be developed as to the most rational choice of the tuning rule for the application. Some preliminary work done to develop an expert system to allow a greater automation of …

A Case Study In Modeling And Process Control: The Control Of A Pilot Scale Heating And Ventilation System, Robin Mooney, Aidan O'Dwyer

Conference papers

This paper details the control of a pilot scale laboratory heating and ventilation system. The system is represented in 2x2 multi-input, multi-output (MIMO) form. A process reaction curve identification technique was used to model (in first order lag plus delay - FOLPD - form) the flow process and temperature process portions of the system, over a range of operating conditions. Tests revealed that both processes were continuously non-linear. A gain scheduler with static decoupling was designed, using look-up tables, to continuously interpolate for the most suitable proportional-integral (PI) or proportional-integral-derivative (PID) controller settings and decoupler gains. The contribution of this …

Pi And Pid Controller Tuning Rules: An Overview And Personal Perspective, Aidan O'Dwyer

Conference papers

The ability of PI and PID controllers to compensate many practical processes has led to their wide acceptance in industrial applications. The requirement to choose two or three controller parameters is most easily done using tuning rules. Starting with a general discussion of industrial practice, the paper provides a survey of additional tuning rules for continuous-time PI and PID control of time-delayed single-input, single-output (SISO) processes, to those explored in a recent book by the author.

Enhancing Waste Management Through Automatic Control, Aidan O'Dwyer

Conference papers

Meeting environmental requirements is recognised as one of the six 21st century business drivers for automatic control. The proportional integral (PI) and proportional integral derivative (PID) controllers are the most dominant form of automatic controllers in industrial use today. With these techniques, it is necessary to adjust the controller parameters according to the nature of the process. Thus, for effective control of a heating, cooling and air-conditioning (HVAC) application, for example, specific values need to be chosen for the P, I and D parameters, which will be different for the values required to control, for example, a distillation column. This …

Reducing Energy Costs By Optimizing Controller Tuning, Aidan O'Dwyer

Conference papers

The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this technique, it is necessary to adjust the controller parameters according to the nature of the process. This tailoring of controller to process is known as controller tuning. Controller tuning is easily and effectively performed using tuning rules (i.e. formulae for controller tuning, based on process information). Such tuning rules allow the easy set up of controllers to achieve optimum performance at commissioning. Importantly, they allow ease of re-commissioning if the characteristics of the process change. The paper outlines the results …

Latency Compensation Control Of Computer Based Control Systems, Aidan O'Dwyer

Conference papers

This paper discusses the use of a modified Smith predictor for latency (i.e. time delay) compensation, to assist in the implementation of network computer based control systems. Such systems typically have a variable time delay associated with the transfer of information; the modified Smith predictor is robust to time delay variations.

Performance Improvement Using Simple Pid Controller Tuning Formulae, Aidan O'Dwyer

Conference papers

The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this technique, it is necessary to adjust the controller parameters according to the nature of the process. Thus, for effective control of a HVDC system, for example, specific values need to be chosen for the P, I and D parameters, which will be different for the values required to control, for example, an induction motor drive. This tailoring of controller to process is known as controller tuning. Controller tuning is easily and effectively performed using tuning rules (i.e. formulae for controller …

Synthesising Life-Sciences And Control Engineering: An Outline Survey And A Practical Example, Aidan O'Dwyer

Conference papers

There is an increasing interest in life science related areas in the electrical and control engineering community [1]. One manifestation of this interest is the development of interdisciplinary programmes, such as the B.Sc. in Medical Physics and Bioengineering, offered by the Dublin Institute of Technology from September 2005. A significant amount of research work in control engineering has focused on aspects of human physiological system, for example blood glucose regulation [2], cardiovascular modelling and control [3], and limb control [4]. There is an increasing emphasis on interdisciplinary research; in recognition of this, the Institute of Electrical Engineers (IEE) has starting …

A Wavelet Controller For Shunt Active Power Filter, Malabika Basu, Biswajit Basu

Conference papers

A wavelet-based controller for shunt active power filter (APF) has been proposed in this paper. The constructed controller based on multi resolution analysis has the advantage of better frequency bandwidth selection. The tuning parameters of the controllers are the gains to be applied to the time-frequency signals at different resolutions. This has the advantage of aiding the process of a proper choice of coefficients of tuning parameters. The developed simulation model of the APF with wavelet-based control shows satisfactory steady state and dynamic performance. A comparison with standard PI controller shows that the dynamic response of the proposed wavelet controller …

Optimising The Rating Of The Upqc For Applying To The Fault Ride Through Enhancement Of Wind Generation, N. G. Jayanti, Malabika Basu, Michael Conlon, Kevin Gaughan

Conference papers

The unified power quality conditioner (UPQC) is a combination of a shunt and a series compensator cascaded via a DC link capacitor which works on the combined principle of active filtering and dynamic voltage restoration. Therefore, the UPQC can be a potential solution to the grid integration problems associated with fixed speed wind generators including reactive power compensation and fault ride through capability. The hardware design of the UPQC can be made more cost effective by proper selection of the rating of the individual compensators of the UPQC. It is shown in the paper that the application of a fixed …

Ber Variation In An Uwb Ofdm Mimo Communications System Based On Measurements Made In A Picocell Wireless Environment, Conor Downing, Pat Chambers, Hussein Baher

Conference papers

A picocell UWB MIMO communications system model is considered which has five orthogonal sub-channels, each with its own OFDM signal. The effect of removing the various channel impulse response components which arise due to the multi-path propogation, a phenomenon characteristic of wide band transmission, is considered. This is a measurement based analysis where the measurements, themselves, were made, in a specially constructed enclosure which had reflective surfaces, using specially designed UWB antennas.

Design Of A Wide-Band Printed Antenna Using A Genetic Algorithm On An Array Of Overlapping Sub-Patches, Matthias John, Max Ammann

Conference papers

No abstract provided.

Wideband Directional Base-Station Antenna With Dual-Linear And Circular-Polarization Capabilities, Francisco Lerma, Matthias John, Giuseppe Ruvio, Max Ammann, N. Herscovici

Conference papers

A crossed-dipole antenna providing polarization diversity is presented. The antenna which employs a planar reflector yields high directivity and good isolation between ports over a wide impedance bandwidth, suitable for polarization-agile wireless base-station use. The dipole wing shape is optimised, which yields the wide bandwidth. Matching is achieved using a quarter-wave balanced-to-unbalanced section which also improves the port-to-port isolation. Radiation characteristics for linear and circular polarizations are presented

Ecue: A Spam Filter That Uses Machine Learning To Track Concept Drift, Sarah Jane Delany, Padraig Cunningham, Barry Smyth

Conference papers

While text classification has been identified for some time as a promising application area for Artificial Intelligence, so far few deployed applications have been described. In this paper we present a spam filtering system that uses example-based machine learning techniques to train a classifier from examples of spam and legitimate email. This approach has the advantage that it can personalise to the specifics of the user’s filtering preferences. This classifier can also automatically adjust over time to account for the changing nature of spam (and indeed changes in the profile of legitimate email). A significant software engineering challenge in developing …

Learning Traditional Irish Music Using A Pda, Bryan Duggan

Conference papers

A common problem experienced by musicians in traditional music sessions is that of recalling tunes on demand from a large repertoire. Traditional music is largely an oral medium and musicians may recall a name or player of a tune or set, but require hearing the first few notes to start the tune. In this paper, we present our work developing TunePal, a tool that can be used by musicians for the storage and retrieval of traditional music melodies for learning purposes. TunePal is specifically desiged to be used by musicians playing Irish traditional music in sessions as it supports the …

Bs News

Building Services Engineering

No abstract provided.

Effect Of Step Sintering On Breakdown Voltage Of Varistors Prepared From Nanomaterials, Suresh Pillai, Declan Mccormack, John Kelly, Ramesh Raghavendra

Articles

No abstract provided.

A Comparison Of Time-Domain Time-Scale Modification Algorithms, David Dorran, Robert Lawlor, Eugene Coyle

Conference papers

Time-domain appraoches to time-scale modification are popular due to their ability to produce high quality results at a relatively low computational cost. Within the category of time-domain implementations quite a number of alternatives exist, each with their own computational requirements and associated output quality. This paper provides a computational and objective output quality assessment of a number of popular time-domain time-scaling implmentations; thus providing a means for developers to identify a suitable algorithm for their application of interest. In addition, the issues that should be considered in developing time-domain algorithms are outlines, purely in the context of a waveform editing …

Refinements In Using Historical Process Data To Optimize Tolerance Allocation, Kevin Delaney, Pat Phelan

Conference Papers

Tolerance allocation for new products calls for experience and judgment. Whenever products are manufactured using production processes that are similar to existing products it is likely that the trend in production tolerances for both the new and existing products will be similar. It must be assumed that there have been no improvements to the tooling, modifications to the machines being used, or a change in process stability. The data employed to understand and exploit these trends is commonly referred to as process capability data and it is stored in a Process Capability DataBase (PCDB). There are several challenges to be …

The Tromped, An In-Flight Exercise Device To Prevent Flight Related Deep Vein Thrombosis, Carolyn Collins, David Kennedy, Thomas Corrigan, Stephen Jerrams

Conference Papers

Medical and Engineering research studies have shown the potential risks of long haul flight travel and methods of preventing it occurring. The risk of serious health problems or even death is known to arise from lack of venous movement and increased coagulation (clotting) of the blood. These factors contribute to the development of deep vein thrombosis (DVT) and this is more likely to occur in situations where people are seated for long periods during travel on land or in air. Currently long haul airlines have yet to be seen to introduce physical preventative measures against this syndrome.

A prototype design …

The Role And Future Of Nanotechnology In Research, Industry And Education, David Kennedy

Conference Papers

Major developments in Nanotechnology have taken place across the world
over the last few years. From a humble beginning, Ireland inc. became a leader in the Microelectronics industry and now has to face the challenge of developing a strategic plan to maintain its lead position in the nano field which in most cases will supersede the micro phase. Most countries are taking a similar path of development all be it alone or in collaboration with other countries. This process is expensive and requires market drivers and experts to lead and deliver demands from the industries of the future. The approach …

A Critical Appraisal Of The Roles Of Public Sector Employees In The Provision Of Educational Buildings Under A Public Private Partnership (Ppp) In The Republic Of Ireland, Louis Gunnigan, David Eaton

Conference papers

Public-Private Partnership (PPP) has now become established as a key element in the Irish Government’s strategy in the provision of school buildings. Specific guidelines have been implemented to define the public sector role in a PPP in Ireland and these guidelines represent a significant change in role from those in the traditional schools procurement process. Through a literature review, this paper maps the PPP process and establishes the new tasks that public sector employees must carry out in the adoption of PPP. The new knowledge, skills and competence (KSC) required to carry out these tasks are noted. Whilst existing literature …

Analysis Of Indentation Loading Of Cortical Bone Using Acoustic Emission Techniques, Ashkan Safari, Ger Reilly, Brendan Mccormack

Conference Papers

In this study, we recorded the number of Acoustic emission (AE) hits and related AE energy during indentation fracture of cortical bone using a PAC PCI-2 card and pico sensor. A threshold value of 43dB was used to filter premature trigger due to background noise. Registered AE hits had more than one count (threshold crossing). Amplifier gain was set at 40dB with a (0.1-1) MHz band pass filter. 8mm cubes of cortical bones were indented in the longitudinal direction at constant crosshead speed of 1 mm min-1 using a large 2D, 50˚ wedge indenter. We hypothesised that signals occurring as …

Bs News

Building Services Engineering

No abstract provided.

Bs News

Building Services Engineering

No abstract provided.

Probalistic Analysis Of Highway Bridge Traffic Loading, Colin C. Caprani

Other resources

Many bridges of the world’s highway networks have been in service for decades and are subject to escalating volumes of traffic. Consequently, there is a growing need for the rehabilitation or replacement of bridges due to deterioration and increased loading. The assessment of the strength of the existing bridge is relatively well understood, whereas the traffic loading it is subject to, is not as well understood. Accurate assessment of the loading to which bridges may be subject, can result in significant savings for the highway maintenance budgets internationally. In recent years, a general approach has emerged in the research literature: …

Excellence In Engineering Education, Mike Murphy

Presentations

No abstract provided.

Performance Evaluation Of Video Streaming With Background Traffic Over Ieee 802.11 Wlan Networks, Nicola Cranley, Mark Davis

Conference papers

There is an increasing demand for multimedia streaming applications over WLAN networks. MPEG-4 and H.264 are compression standards targeted at high-quality streamed multimedia services over wireless best-effort IP networks. However, the dynamic nature of wireless networks in terms of fluctuating bandwidth and time-varying delays makes it difficult to provide good quality streaming under such constraints. Multimedia streaming applications are a demanding and challenging service to deliver over wireless networks. There is a trade-off between the capacity of the wireless network and the quality of the multimedia streaming application. In this paper we investigate the effect the background traffic load has …

Bs News

Building Services Engineering

No abstract provided.