Engineering Commons^™

Operational Analysis Of Improved Γ-Z-Source Inverter With Clamping Diode And Its Comparative Evaluation, Zeeshan Aleem, Mohamed Moin Hanif

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Due to a substantial shortage of conventional energy sources, the utilization of renewable energy is gaining attention. Power converters form interfaces to provide power from renewable energy sources to end user systems. Impedance-source inverters (ZSIs) have become a research hotspot and are widely used to overcome the drawbacks of conventional voltage-source inverters and current-source inverters such as two-stage power conversion and less immunity to electromagnetic interference noises. This paper presents various transformer-based ZSIs mainly classified as trans-ZSIs, improved trans-ZSIs, inductor-capacitor-capacitor transformer ZSI, TZSIs, and their comparisons with a new family of ZSIs called Γ-Z-source inverters (ΓZSI). Full operational analysis of …

Grid Voltage Sensorless Single-Phase Half-Bridge Active Filter And Dc Bus Voltage Regulation, Samet Biricik

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In this paper, a method is presented for the control of grid voltage sensorless single-phase half-bridge shunt active power filter to reduce the grid current harmonics of low-power single-phase non-linear loads. The proposed system forces the grid current to be sinusoidal without sensing and processing the grid voltage on the line. For this reason, instead of grid voltage the load current is processed by using self-tuning filter to generate reference grid current to eliminate current harmonic distortions. In order to design a low-cost system, a half-bridge voltage source converter is used to reduce driver circuits. In addition, the switching losses …

Geospatial Drivers Of The Groundwater Δ18o Isoscape In A Temperate Maritime Climate (Republic Of Ireland), S. Regan, R. Goodhue, O. Naughton, Paul Hynds

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In recent years, the concept of “isoscapes” has been used to describe spatiotemporal stable isotope distributions within natural environments including groundwater systems at multiple scales. This study presents an updated groundwater δ18O isoscape for the Republic of Ireland and describes the climatic and geological drivers influencing 18O composition. In all, 142 geographically and geologically representative groundwater installations were sampled and analysed, in addition to 35 samples from six nested boreholes. Geospatially, Irish groundwater exhibits high δ18O values in southern and western coastal regions, becoming progressively depleted inland before reaching lowest measured values along the eastern coast, equating to a national …

Technological Assessment Of Different Solar-Biomass Systems For Hybrid Power Generation In Europe, Cm Iftekhar Hussain, Brian Norton, Aidan Duffy

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Solar Tower thermal (ST), Parabolic Trough thermal (PT), Linear Fresnel thermal (LF) and Solar PV are discussed in the context of suitability for hybridization with biomass in Europe. Technical, economical and climate data have been compared to identify the key drivers of technology selection in setting up large scale solar-biomass hybrid power plants. The sole solar-biomass hybrid power plant is currently in operation in Spain uses PT technology due to its performance characteristics, comparatively easy installation process compared to ST and relatively higher heat and optical gain than LF. The climate condition in the EU shows that the region within …

A Literature Review Of The Evolution Of British Prefabricated Low-Rise Housing, Daniel O'Neill, Samantha Organ

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Purpose – The purpose of this paper is to explore academic papers and reports and present a chronology of the evolution of British low-rise prefabricated housing. The paper provides chronological information for construction and surveying researchers undertaking research in associated areas.

Design/methodology/approach – This is a qualitative literature review, providing an exploration and analysis of academic papers and reports on low-rise prefabricated housing.

Findings – A substantial literature was discovered. However, there are gaps in the available literature. The history of British construction technology is a rich research area but is under-researched. Prefabricated housing has a long history dating back …

A New Educational Mobile Devices Platform For Social Inclusion In Tanzania, Fredrick Mtenzi

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Abstract— It is evident that advances in technology has led to improvement in societal wellbeing. In this paper we demonstrate how mobile phones are used in providing reliable and quality education to students in disadvantaged areas of Tanzania. The main contribution is on leveraging on the success that Tanzania has had on using mobile banking to the un-banked population. These lessons are adapted to the education sector, where clever/smart integration of existing disruptive technologies such as mobile phones and social networks are be used to provide access to high quality educational contents. Further, the paper shows how educational content can …

Time Series Analysis For A 1/Tb Memory Function And Comparison With The Lyapunov Exponent Using Volatility Scaling, Paddy Walsh, Jonathan Blackledge

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Being able to provide accurate forecasts on the trending behaviour of time series is important in a range of applications involving the real time evolution of signals, most notable in financial time series analysis but control engineering in general. A critical solution for providing high accuracy forecasts is the filtering operation used to identify the position in time at which a trend occurs subject to a time delay factor that is inherent in the filtering strategy used. The paper explores this strategy and presents some example results that provide a quantitative measure of the accuracy used.

Risk Management In Motorway Ppp Projects: Empirical-Based Guidelines, Nunzia Carbonara, Nicola Costantino, Louis Gunnigan, Roberta Pellegrino

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This paper deals with the topic of risk management in Public–Private Partnership (PPP). The analysis of the related literature reveals that risks must be analyzed and managed on a context-specific approach, and that there is a lack of a comprehensive study on the appropriate risk mitigation strategies for each risk embedded in PPP projects. Focusing on the transport sector, based on the results of a Delphi survey, the paper provides guidelines for both public and private parties in defining a list of significant risks in PPP motorway projects, and identifying for them both the effective allocation and the suitable mitigation …

What Makes A Technology Appropriate?, Barrett Hazeltine

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No abstract provided.

Purchasing Green Transport And Logistics Services: Implications For Small Business, Pietro Evangelista, Maria Huge-Brodin, Karin Isaksson, Edward Sweeney

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Considering its strong environmental impact, logistics plays a critical role in green supply chain management. It provides strategic links in the supply chain and is an essential function in the delivery of green products to the consumer. There is a general consensus on the fact that more environmentally sustainable companies may be achieved only if transport and logistics activities also become greener. To achieve this objective, buyer companies need to incorporate green considerations in the purchasing of transport and logistics services. This appears particularly challenging for small and medium sized enterprises (SMEs) because of their traditional lack of managerial, organisational …

Evaluation Of A Prototype Desktop Virtual Reality Model Developed To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge

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The use of Desktop Virtual Reality (VR) systems for enhancing electrical safety and engineering design is a novel prospect for both practicing and student electrical services engineers. This innovative approach, which can be readily accessed via the World Wide Web, constitutes a marked shift in conventional learning and design techniques to a more immersive, interactive and intuitive working and learning environment. This paper initially identifies the unique characteristics of desktop web based VR technologies and highlights the educational affordances offered by working in such an environment. Subsequently, using a prototype model titled ‘Virtual Electrical Services’, a case study is carried …

Non-Gaussian Anisotropic Diffusion Processing For Medical Imagining Using The Osirix Dicom Viewer, Jonathan Blackledge, Matthew Blackledge, Jane Courtney

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Medical imaging is a fertile area for computer graphics, image processing and real time visualization. In this paper we present a method for reducing noise in CT (Computed Tomography) and MR (Magnetic Resonance) images that (in addition to other noise sources) is characteristic of the numerical procedures required to construct the images, namely, the (inverse) Radon Transform. In both cases, MR imaging in particular, an additional noise source is due to the process of diffusion thereby predicating use of the Anisotropic Diffusion method for noise suppression. This method is based on a diffusion model for noise generation where the Diffusivity …

Analysis Of Wind Velocity And The Quantification Of Wind Turbulence In Rural And Urban Environments Using The Levy Index And Fractal Dimension, Jonathan Blackledge, Eugene Coyle, Niall Mccoy, Derek Kearney, Keith Sunderland, Thomas Woolmington

Articles

This paper is concerned with a quantitative and comparative analysis of wind velocities in urban and rural environments. It is undertaken to provide a route to the classification of wind energy in a rural and urban setting. This is a common problem and the basis of a significant focus of research into wind energy. In this paper, we use a non-Gaussian statistical model to undertake this task, and, through a further modification of the data analysis algorithms used, extend the model to study the effect of wind turbulence, thereby introducing a new metric for this effect that is arguably superior …

Non-Gaussian Analysis Of Wind Velocity Data For The Determination Of Power Quality Control, Jonathan Blackledge, Eugene Coyle, Derek Kearney

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The quality of power (i.e. the sustainable power output as a function time) of any wind dependent energy converter (including wind turbines and wave energy converters) is determined by many design and environmental factors but timedependent variations in the wind speed are arguably the most important. In this paper we consider a non-Gaussian model for analysing and then simulating wind velocity data. In particular, we consider a Lévy distribution for the statistical characteristics of wind velocity and show how this distribution can be used to derive a stochastic fractional diffusion equation for the wind velocity as a function of time …

Using Virtual Reality To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge, Eugene Coyle

Articles

— Electricity and the inherent risks associated with its use in the built environment have long since been a priority for the electrical services industry and also the general public who must live and work in this environment. By its nature virtual reality has the advantage of being safe for both the user and equipment. In addition, it offers the user an opportunity to be exposed to a range of scenarios and conditions that either occur infrequently or are hazardous to replicate. This paper presents a prototype desktop virtual reality model, to enhance electrical safety and design in the built …

Rainwater Harvesting And Greywater Treatment Systems For Domestic Application In Ireland, Zhe Li, Fergal Boyle, Anthony Reynolds

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Water shortage has been recognised as one of the key issues facing many countries. Fortunately, there are relatively abundant water resources available in Ireland because of its plenty of rainfall. However, Ireland will inevitably encounter water shortage in the future, especially in urban areas. The water consumption per capita per day in Ireland is one of the highest in Europe. The water demand is still increasing due to population growth and higher standard of living. The use of domestic rainwater harvesting and greywater treatment systems has the potential to supply nearly 94% of domestic water in Irish households. The utilisation …

Rebuilding After Disaster - Engineering Lessons From The 2004 Tsunami, Liam Mccarton

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On 26th December 2004 a magnitude 9 earthquake occurred off the west coast of northern Sumatra, Indonesia. The sudden and violent vertical displacement of the sea floor caused a disturbance to the overlying water column, which generated waves (tsunami) that propagated rapidly across the whole of the Indian Ocean. Typically, in open ocean waters, these waves have long wavelengths of the order of 200km and low trough to crest amplitudes. These properties allow them to conserve energy as they propagate over large distances. As the waves enter the shallower waters of coastal areas, their amplitude increases dramatically and their velocity …

Using Virtual Reality To Enhance Electrical Safety And Design In The Built Environment, Martin Barrett, Jonathan Blackledge, Eugene Coyle

Articles

Electricity and the inherent risks associated with its use in the built environment have long since been a priority for the electrical services industry and also the general public who must live and work in this environment. By its nature virtual reality has the advantage of being safe for both the user and equipment. In addition, it offers the user an opportunity to be exposed to a range of scenarios and conditions that either occur infrequently or are hazardous to replicate. This paper presents a prototype desktop virtual reality model, to enhance electrical safety and design in the built environment. …

Engineering Of A Single Alkaline Fuel Cell Part Ii: Long Term Operation In Air, Jonathan Blackledge, Eugene Coyle, David Kennedy, Heinz Schmidt-Walter, Hans Kohnke, Steffen Schudt, Gerhard Sauer, James Hamilton

Articles

Research into renewable energy sources has previously lacked sufficient investment. However, emphasis has now shifted and funding is being made available in a proactive manner by various governments eager to encourage renewable energy technology and reduce carbon taxes. Fuel Cells offer a realistic, sustainable and clean alternative energy option for stationary and mobile applications. Hydrogen and fuel cell technologies are recognised by many as possible long term energy solutions, but to-date, have failed to make an impact on the energy market. This is due to a number of key reasons, some of which include efficiency, scale, accessories and power output. …

Engineering Of A Single Alkaline Fuel Cell Part I: Construction Of A Test Bed, Jonathan Blackledge, James Brunton, Eugene Coyle, David Kennedy, Heinz Schmidt-Walter, Hans Kohnke, Gerhard Sauer, Steffen Schudt, James Hamilton

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Fuel Cells offer a realistic, sustainable and clean alternative energy option for stationary and mobile applications. Hydrogen and fuel cell technologies are recognised by many as possible long term energy solutions, but to-date have failed to make an impact on the energy market. This is due to a number of key reasons, some of which include, efficiency, scale, accessories and power output. Applying fuel cells to small telecommunication components requires the applications of Micro and Nanotechnology, which have yet to be perfected to make them long lasting and cost effective. This paper outlines the reasons for commercialisation of fuel cells …

Object Detection And Classification With Applications To Skin Cancer Screening, Jonathan Blackledge, Dmitryi Dubovitskiy

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This paper discusses a new approach to the processes of object detection, recognition and classification in a digital image. The classification method is based on the application of a set of features which include fractal parameters such as the Lacunarity and Fractal Dimension. Thus, the approach used, incorporates the characterisation of an object in terms of its texture.

The principal issues associated with object recognition are presented which includes two novel fast segmentation algorithms for which C++ code is provided. The self-learning procedure for designing a decision making engine using fuzzy logic and membership function theory is also presented and …

Why Renewables Need Nuclear?: A Brief Narrative, John Ratcliffe, Ruth Saurin

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No abstract provided.