Engineering Commons^™

Mid-Infrared Raman Sources Using Spontaneous Raman Scattering In Germanium Core Optical Fibers, Pengfei Wang, Christy Charlton O'Mahony, Timothy Lee, Rand Ismaeel, Thomas Hawkins, Yuliya Semenova, Lin Bo, Qiang Wu, Colette Mcdonagh, Gerald Farrell, John Ballato, Gilberto Brambilla

Articles

Mid-infrared Raman sources based on spontaneous Raman scattering have been demonstrated in a 15-lm diameter glass-clad crystalline germanium optical fiber and in a germanium-wire. A quantum cascade laser was used as pump at a wavelength of 5.62 lm. Because of their ultra-high optical nonlinearities and extremely broad transparency window, germanium core fibers offer the possibility of fabricating compact and efficient mid-infrared sources.

Learning From Learning Groups, Mike Murphy, S. M. Chance, Gavin Duffy, Brian Bowe

Articles

Collaborative learning is a key, and complementary, component of student-centred enquiry-based pedagogy. Today, many educators understand that students learn effectively when working together with their peers to construct new knowledge. Many teachers are working to help their students develop such ability. Teachers do this to help students better understand the relevance of new content, connect new ideas into existing frameworks of understanding, and construct new neurological pathways and connect synapses in their brains. In addition, group learning has been shown to increase students’ critical thinking skills, creativity, collaborative behaviours, understanding of ethics, and the like. In the literature, attention has …

A Highly Efficient Tio2-Xcx Nano-Heterojunction Photocatalyst For Visible-Light Induced Antibacterial Applications, Vinodkumar Etacheri, Michael Seery, Stephen Hinder, Georg Michlits, Suresh Pillai

Articles

Visible-light-induced antibacterial activity of carbon-doped anatase-brookite titania nano-heterojunction photocatalysts are reported for the first time. These heterostructures were prepared using a novel low temperature (100 °C) non-hydrothermal low power microwave (300 W) assisted method. Formation of interband C 2p states was found to be responsible for the band gap narrowing of the carbon doped heterojunctions. The most active photocatalyst obtained after 60 minutes of microwave irradiation exhibits a 2-fold higher visible-light induced photocatalytic activity in contrast to the standard commercial photocatalyst Evonik-Degussa P-25. Staphylococcus aureus inactivation rate constant for carbon-doped nano-heterojunctions and the standard photocatalyst was 0.0023 and -0.0081 min …

Finite Element Analysis Of Balloon-Expandable Coronary Stent Deployment: Influence Of Angioplasty Balloon Configuration, David Martin, Fergal Boyle

Articles

Today, the majority of coronary stents are balloon-expandable and are deployed using a balloon-tipped catheter. To improve deliverability, the membrane of the angioplasty balloon is typically folded about the catheter in a pleated configuration. As such, the deployment of the angioplasty balloon is governed by the material properties of the balloon membrane, its folded configuration and its attachment to the catheter. Despite this observation, however, an optimum strategy for modelling the configuration of the angioplasty balloon in finite element studies of coronary stent deployment has not been identified, and idealised models of the angioplasty balloon are commonly employed in the …

Impact Of Intermetallic Precipitates On The Tribological And/Or Corrosion Performance Of Cast Aluminium Alloys: A Short Review, David Culliton, Tony Betts, David Kennedy

Articles

The role of various intermetallic precipitates (IMP), or secondary phase particles, in governing the wear and corrosion performance characteristics of cast aluminium alloys is outlined in this brief review. Such alloys are especially important in transport applications where their low weight, low cost and recyclability make them very attractive. However alloy wear and/or corrosion behaviour often limit their industrial application and more work needs to done to extend their use into other areas. Careful control of IMP nucleation and growth rates may be beneficial, especially in alloys exposed to corrosive environments. Silicon, copper and magnesium are all important elements for …

Derivation Of A Fuzzy National Phosphorus Export Model Using 84 Irish Catchments, Ahmed Nasr, Michael Bruen

Articles

Implementation of appropriate management strategies to mitigate diffuse phosphorus (P) pollution at the catchment scale is vitally important for the sustainable development of water resources in Ireland. An important element in the process of implementing such strategies is the prediction of their impacts on P concentrations in a catchment using a reliable mathematical model. In this study, a state-of-the-art adaptive neuro-fuzzy inference system (ANFIS) has been used to develop a new national P model capable of estimating average annual ortho-P concentrations at un-gauged catchments. Data from 84 catchments dominated by diffuse P pollution were used in developing and testing the …

Manufacturing Strategy & Operations: Reflections On Key Current Issues: Challenges And Associated Human Resource Implications, Lorraine Mcgrath

Books/Book chapters

This chapter evaluates the current issues and challenges in defining a company’s manufacturing strategy and its production operations in consideration of the contemporary shift to low cost manufacturing locations. Competitive priorities of cost, quality, delivery and flexibility are reviewed. The structural and infrastructure elements of a manufacturing strategy are outlined. Mitigating risks in a global arena are reviewed. Collaborative efforts, including the cultural and personality issues of being human are included in the discussion of managing diversity in such a highly competitive and challenging enterprise resource planning environment.

The Integration Of Sustainable Development Competencies In Irish Engineering Education: Findings Of A Curriculum Content Investigation Of Four Engineering Programmes, Iacovos Nicolaou, Eddie Conlon

Conference papers

This paper presents the initial findings of an investigation of the Sustainable Development (SD) content in five professional engineering degree programmes in a large Irish Institute of Technology.

A comprehensive investigation of the modules content was conducted to see to what extent the learning outcomes for SD as set out in the Barcelona Declaration and SD competencies were covered by the modules. It was found that 40% of the 137 modules included SD learning outcomes and/or addressed SD competencies. The modules have a focus on environmental issues and tend to address only one of the three dimensions, environmental, social and …

Near Field Radiation Patterns For An Ultra-Wide-Band Antenna, Jonathan Blackledge, Bazar Babajanov

Conference papers

We present a three-dimensional time dependent model for simulating the electromagnetic radiation field patterns generated by Ultra-Wide- Band (UWB) antennas. UWB antennas are pulsed mode radiators used to communicate information at high bit rates over short distance. This affects the spatial characteristics of the field patterns assumed to be generated when a Continuous Wave (CW) model is used and this paper investigates the difference between the near field intensity patterns generated when a pulse and CW mode is used. The purpose of this is to develop a numerical simulation that provides information on the three-dimensional electromagnetic field subject to a …

A New Tool For Qt Interval Analysis During Sleep In Healthy And Obstructive Sleep Apnea Subjects: A Study On Women, Kemal Ali̇can Kaya, Bülent Yilmaz

Turkish Journal of Electrical Engineering and Computer Sciences

By monitoring the Q wave/T wave (QT) interval computed from electrocardiography (ECG) signals during sleep, it is possible to create a link between the ventricular repolarization and sleep stages. In this study, we aimed to find a robust and simple approach to automatically determine the fiducials on each 30-s sleep epoch, such as the Q, R, and T-end points, on long sleep ECG recordings in order to statistically analyze the effect of obstructive sleep apnea (OSA) and sleep stages on QT intervals. This is a retrospective study in which the ECG data extracted from the polysomnography recordings of 7 healthy …

Estimation Of Fuel Cost Curve Parameters For Thermal Power Plants Using The Abc Algorithm, Yusuf Sönmez

Turkish Journal of Electrical Engineering and Computer Sciences

The solution accuracy of economic dispatch problems is associated with the accuracy of the fuel cost curve parameters. Therefore, updating of these parameters is a very important issue to further improve the final accuracy of economic dispatch problems. Estimating the parameters of the fuel cost curve may be the best solution for this issue. This paper presents an application of the artificial bee colony (ABC) algorithm to estimate the fuel cost curve parameters of thermal power plants. In the estimation problem, 1st-, 2nd-, and 3rd-order fuel cost functions are used, and the estimation problem is formulated as an optimization one. …

Preserving Location Privacy For A Group Of Users, Maede Ashouri-Talouki, Ahmad Baraani Dastjerdi, Ali̇ Aydin Selçuk

Turkish Journal of Electrical Engineering and Computer Sciences

Location privacy is an interesting problem that has been receiving considerable attention. This problem has been widely discussed from the individual point of view; however, there exist only a few works that support location privacy for a group of users. In this paper we consider the problem of supporting location privacy for a group of users during the use of location-based services (LBSs). We assume a group of users who want to benefit from a LBS and find the nearest meeting place that minimizes their aggregate distance. Each user in this scenario wants to protect his or her location from …

Swarm Optimization Tuned Mamdani Fuzzy Controller For Diabetes Delayed Model, Mohammad Hassan Khooban, Davood Nazari Maryam Abadi, Alireza Alfi, Mehdi Siahi

Turkish Journal of Electrical Engineering and Computer Sciences

Diabetes is a chronic disease in which there are high levels of sugar in the blood. Insulin is a hormone that regulates the blood glucose level in the body. Diabetes mellitus can be caused by too little insulin, a resistance to insulin, or both. Although research activities on controlling blood glucose have been attempted to lower the blood glucose level in the quickest possible time, there are some shortages in the amount of the insulin injection. In this paper, a complete model of the glucose--insulin regulation system, which is a nonlinear delay differential model, is used. The purpose of this …

Orthogonal Array Based Performance Improvement In The Gravitational Search Algorithm, Ökkeş Tolga Altinöz, Asim Egemen Yilmaz, Gerhard Wilhelm Weber

Turkish Journal of Electrical Engineering and Computer Sciences

The gravitational search algorithm (GSA) is a novel heuristic method inspired by Newton's gravity and velocity equations. In addition, it is a population-based algorithm, in which each member (called an agent) in the population has a mass, velocity, and acceleration. Beginning with the first population state, agents influence each other via mass and velocity relations. This mutual effect causes agents to reach the optimum. Hence, the performance of the GSA to attain the optimum is related to the initial population formation, like other population-based algorithms. In this study, the orthogonal array (OA) concept is applied and injected to the GSA …

A New Technique For Rare-Event Simulation Based On Partition Of The Region, Amir Jalaly Bidgoly, Mohammad Abdollahi Azgomi

Turkish Journal of Electrical Engineering and Computer Sciences

Rare events are an important limitation of discrete-event simulation in some areas of applications. The existing rare-event simulation (RES) techniques, such as importance sampling (IS), splitting, and RESTART, have been used for RES so far. However, these techniques not only have some limitations, but also are not general or easy to use. In this paper, the partition of the region (PoR) method is used as a variance reduction technique in a new RES technique for usage with a wide range of modeling and simulation languages. Three variants of the proposed technique will be introduced: simple PoR, recursive PoR, and advanced …

Model Of A Photovoltaic Panel Emulator In Matlab-Simulink, Hayretti̇n Can

Turkish Journal of Electrical Engineering and Computer Sciences

Being able to behave electrically similar to photovoltaic (PV) panels, PV emulator systems make it possible to perform different PV system tests under various operation conditions. In this paper, a model of a PV panel emulator is presented using the Power System Blockset under MATLAB-Simulink. The simulation of the emulator system is developed for testing a controller prior to a real-time implementation. The model can handle the dependence of all of the parameters in the model with respect to solar radiation and temperature. The simulation results show that the output characteristics of the simulator have good agreement with those of …

Control, Design, And Implementation Of A Low-Cost Ultracapacitor Test System, Hasan Hüseyi̇n Eroğlu, Ahmet Masum Hava

Turkish Journal of Electrical Engineering and Computer Sciences

This paper reviews the ultracapacitor (UC) test procedures, establishes simple and economical power electronic conversion system-based UC test equipment, and experimentally evaluates the performance of a UC module. The power converter hardware structure and control algorithms of the designed system are discussed in detail. The high bandwidth and high accuracy current programming capability of the converter for the purpose of charging and discharging the UC, as required during testing, is illustrated via the experimental results. The UC equivalent circuit parameters are extracted. Successful constant current and constant power charging/discharging operating performances are demonstrated. The results of this study help with …

An Event-Driven Wsn Mac Protocol Design Based On Active Node And Dynamic Time Slot Allocation, Nükhet Sazak, İsmai̇l Ertürk, Etem Köklükaya, Murat Çakiroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

The unique features of wireless sensor networks (WSNs) make them suitable for a wide range of applications in many different areas. However, with many of the protocols and algorithms used in traditional wireless networks, it is usually neither feasible nor possible to apply them directly to WSNs due to the strict resource constraints of tiny sensor nodes. Moreover, application-specific approaches for communication protocols are usually imposed since WSN applications have distinct requirements. In this study, event-driven WSN applications, where a number of sensor nodes are randomly and densely deployed in remote and difficult to reach locations, are targeted. In such …

Role Of Energy Management In Hybrid Renewable Energy Systems: Case Study-Based Analysis Considering Varying Seasonal Conditions, Recep Yumurtaci

Turkish Journal of Electrical Engineering and Computer Sciences

The recent popularity of alternative energy technologies is mainly promoted by the increasing awareness of environmental concerns as well as the economic impacts of the depleting fossil fuel reserves. Among several alternative technologies, wind- and solar-based energy have been given specific importance with government-based support for providing a cost-effective structure to realize better penetration of such environmentally friendly sources in the energy market. Even these sources are advantageous over the conventional means of energy production from many aspects, a main drawback being the total dependence on the meteorological conditions (wind speed, solar radiation, temperature, etc.) of the wind and solar …

Opf-Based Reactive Power Planning And Voltage Stability Limit Improvement Under Single Line Outage Contingency Condition Through Evolutionary Algorithms, Sakthivel Padaiyatchi, Mary Daniel

Turkish Journal of Electrical Engineering and Computer Sciences

Reactive power planning is vital for maintaining the voltage stability of power systems and evolutionary algorithms are highly useful for achieving this task. This paper compares the effectiveness of the differential evolution (DE) and evolutionary programming (EP) algorithms in optimizing the reactive power planning of power systems under line outage contingency conditions. DE is efficient in exploration through the search space of the problem, while EP is simple and easy to implement. The low cost but fast response thyristor-controlled series capacitor (TCSC) flexible alternating current transmission system (FACTS) device is incorporated to control the power flows. The optimal settings of …

Analysis Of A Multi-Server Queueing Model With Vacations And Optional Secondary Services, Srinivas R. Chakravarthy

Industrial & Manufacturing Engineering Publications

In this paper we study a multi-server queueing model in which the customer arrive according to a Markovian arrival process. The customers may require, with a certain probability, an optional secondary service upon completion of a primary service. The secondary services are offered (in batches of varying size) when any of the following conditions holds good: (a) upon completion of a service a free server finds no primary customer waiting in the queue and there is at least one secondary customer (including possibly the primary customer becoming a secondary customer) waiting for service; (b) upon completion of a primary service, …

Identifying High And Low Walkable Neighbourhoods Using Multi-Disciplinary Walkability Criteria, Lorraine Fitzsimons D'Arcy, Kevin M. Leyden, Catherine Woods

Conference papers

Neighbourhood features contributing to the walkability (pedestrian friendliness) of a neighbourhood are diverse and depend on both its physical and social attributes. Earlier work in the Cleaner, Greener, Leaner (CGL) Study identified differences in opinion between professional stakeholder groups (planners, designers, engineers, public representatives, and public health and advocacy professionals) on what constitutes a walkable environment [1]. This diversity has implications for neighbourhood design and planning policy. The findings of a multi-disciplinary focus group study were used to generate a list of walkability criteria to select areas for a population study. In this study twenty areas were shortlisted and grouped …

About The Library (2013), Georgia Southern University, Zach S. Henderson Library

Program Accreditation Reports (2013-2023)

This document includes information about the Zach S. Henderson Library's mission, facilities, collection and services. The data in the document is based on the fiscal year 2013 Annual Report.

Library Holdings (2013) Ce Report, Georgia Southern University, Zach S. Henderson

Program Accreditation Reports (2013-2023)

This document is a part of the 2013 Library Holdings Report for the Zach S. Henderson Library at Georgia Southern University. The report includes data for the library resources and services supporting the research of the Allen E. Paulson College of Engineering and Computing, Department of Civil Engineering and Construction.

Achieving A Holistic View Of The Life Cycle Performance Of Existing Dwellings, Albert Famuyibo, Aidan Duffy, P. Strachan

Articles

Models which fully evaluate the life cycle energy and greenhouse gas (GHG) emissions of national housing stocks are not reported in literature. Capturing a holistic view of energy and emissions of the residential sector is an important process that can lead to a more effective policy making. This paper presents a methodology which evaluates the life cycle energy and GHG emissions of retrofitting housing stocks considering all life cycle stages and incorporating, to the greatest extent possible, all upstream inputs.

To achieve this, we developed a hybrid model of the existing Irish housing stock, comprising a process-based approach supplemented by …

Correspondence: Comparing Led Luminaires, James Duff

Articles

A recent editorial within Lighting Research and Technology 1 suggests the need for ‘a simple set of questions to ask the LED supplier’. This article will present such a set of questions, but also, and perhaps more importantly, a set of responses that might be considered appropriate. The information used to form these questions and answers has been drawn from a number of useful resources 2-7, interaction with various lighting professionals and through the authors own experience. The purpose of these questions is to generate discussion. The author understands the questions posed can be improved upon and it is hoped …

Lumped Time-Delay Compensation Scheme For Coding Synchronization In The Nonlinear Spectral Quantization-Based All-Optical Analog-To-Digital Conversion, Zhe Khang, Jinhui Yuan, Qiang Wu, Tao Wang, Sha Li, Chongxiu Y, Gerald Farrell

Articles

this paper, we propose a novel lumped time-delay compensation scheme for the all-optical analog-to-digital conversion based on soliton self-frequency shift and optical interconnection techniques. By inserting a segment of negative dispersion fiber between the quantization and the coding module, the time delay of different quantized pulses can be accurately compensated with a simple structure compared to the multiple time-delay lines. The simulation results show that the coding pulses can be well synchronized using a span of fiber, with the flattened negative dispersion within the wavelength range of 1558-1620 nm. In addition, the problems of pulse broadening and time error are …

Biaxial Order Parameter In The Homologous Series Of Orthogonal Bent-Core Smectic Liquid Crystals, S. Sreenilayam, Yuri Panarin, J. K. Vij, M. Osipov, A. Lehmann, C. Tschierske

Articles

The fundamental parameter of the uniaxial liquid crystalline state that governs nearly all of its physical properties is the primary orientational order parameter (S) for the long axes of molecules with respect to the director. The biaxial liquid crystals (LCs) possess biaxial order parameters depending on the phase symmetry of the system. In this paper we show that in the first approximation a biaxial orthogonal smectic phase can be described by two primary order parameters: S for the long axes and C for the ordering of the short axes of molecules. The temperature dependencies of S and C are obtained …

Using Modelling And Simulation To Improve Elderly Care In Ireland: A Case Study, Mohamed Ragab, Wael Rashwan, Waleed Abo-Hamad, Amr Arisha

Articles

Health care services both globally and domestically - are encountering critical issues due to the increasing demand for services at the time of economic recession. Hospital performance is subject to many constraints, and planning is made more difficult by the complexity and uncertainty of demand. Population ageing is creating immense pressures on healthcare facilities across the world, leaving them struggling to cope with the growing demand for elderly healthcare services. Current demand-supply gaps result in prolonged waiting times for patients and substantial cost burdens for healthcare systems due to delayed discharges. This paper reports on a project that uses modelling …

A Model Experiment To Assess The Effects Of Inclusions On Wave Propagation In Soil Media, Thomas Houston

Theses and Dissertations

The research described involved analyzing and characterizing changes to propagating surface waves that are caused by items embedded in a half-space consisting of a soil medium. Numerical and experimentally obtained data of three-dimensional surface wave responses to dynamic impulse loading were examined. Results from this research are compared to changes to surface waves observed in previous investigations that were caused by the presence of voids and inclusions embedded in an elastic half space. The focus of this work was to identify whether the characteristic responses identified in previous studies, based substantially on analytical and finite element analyses results, can be …