Engineering Commons^™

Architecture--Performance Interrelationship Analysis In Single/Multiple Cpu/Gpu Computing Systems: Application To Composite Process Flow Modeling, Richard Harrison Haney

Dissertations

Current developments in computing have shown the advantage of using one or more Graphic Processing Units (GPU) to boost the performance of many computationally intensive applications but there are still limits to these GPU-enhanced systems. The major factors that contribute to the limitations of GPU(s) for High Performance Computing (HPC) can be categorized as hardware and software oriented in nature. Understanding how these factors affect performance is essential to develop efficient and robust applications codes that employ one or more GPU devices as powerful co-processors for HPC computational modeling. The present work analyzes and understands the intrinsic interrelationship of both …

Using Grounded Theory To Develop A Framework For Software Testing Best Practice In A Telecommunications Company, David Hendrick

Dissertations

Software testing is a key part of the software development process, irrespective of the development methodology being followed. Estimates suggest that testing can account for more than 50% of the cost of a software development project. However, the cost of inadequate testing or verifying software can be far greater; this can result in losses that could total more than 10% of an organisation’s turnover. It is clear that software testing is essential; but while many companies implement different forms of testing, there is often no structure or best practice followed to this testing. There appears to be a gap in …

An Investigation Into Energy Consumption And Existing Energy Management Practices In A Dublin Sports Centre, Colin J. Conway

Dissertations

Rising energy costs are a concern to all businesses but especially to those who have a large energy demand. Sports centres with swimming pools have large requirements for heat and electricity in order to maintain thermal comfort within the pool and surrounding areas.

Sports centres which were built in the 1970s were designed at a time when energy was cheap and many of today’s control strategies and energy efficiency measures were unavailable.

This project is an investigation into the electrical and thermal consumption of the Tallaght Sports Complex. The Tallaght Sports Complex was built in the 1970s and is lacking …

An Evaluation Of Seawater Pumped Hydro Storage For Regulating The Export Of Wind Energy To The National Grid, Eoin D. Mclean

Dissertations

Hydroelectric power generation has been in use for a very long time. From the earliest watermills to the current large scale Hydro power plants, this is a technology that is proven to be reliable and commercially viable. The use of wind energy to provide mechanical power for the purpose of turning a rotor is also not a new concept.Four years ago TCD Professor of Applied Physics Igor Shvets conceived the idea of solving Ireland’s energy crisis by taking these two proven renewable technologies and combining them. (McGreevey, 2012) The spirit of Ireland initiative seeks to resolve the biggest issues facing …

Applying Data Visualisations To Open New Perspectives In Birdwatching, Frank Kendlin

Dissertations

Advances in data analytics for big data have affected many different domains and are providing new insights from these data for their respective communities. One such community is conservation science. A part of section of this community, ornithologists and bird conservationists has at its disposal millions of volunteers willing to contribute to a new ‘big’ data set. This can be achieved by means of new technology and the use of citizen science. This is already underway in North America through the excellent work of the Cornell Laboratory of Ornithology (CLO). This institute has harnessed the technology and the people and …

Retaining The People Who Know Your Business Exploring Knowledge Sharing As A Tool To Improve Employee Retention In The Hotel Sector, Vincent Mckenna

Dissertations

The retention of core workers in the hotel/hospitality sector is a key challenge for human resource management, organisational strategies and operational effectiveness. The purpose of this research was to investigate and evaluate the impact of the introduction of knowledge sharing tools/techniques and change in work practice on the retention attitudes of knowledge workers in two context specific environments. Problems relating to the retention of knowledge workers are not confined to Ireland and are shown in this project to be a global phenomenon.

This research project is based on a knowledge audit of core knowledge workers/assets in two context specific environments …

Application Of Nano-Imprint Lithography For Next Generation Carbon Nanotube-Based Devices, Svitlana Fialkova

Dissertations

This research report addresses the development of 3D carbon nanostructures that can provide unique capabilities for manufacturing carbon nanotube (CNT) electronic components, electrochemical probes, biosensors and tissue scaffolds. The shaped CNT arrays were grown on patterned catalytic substrate by chemical vapor deposition (CVD) method. The new fabrication process for catalyst patterning based on combination of nano-imprint lithography (NIL), magnetron sputtering and reactive etching techniques was proposed and studied. The optimal process parameters for each technique were evaluated. The catalyst was made by deposition of Fe and Co nanoparticles over alumina support layer on Si/SiO₂ substrate. The metal particles were …

Modeling Decision Making In Trauma Centers From The Standpoint Of Complex Adaptive Systems, Castanon De Policarpo

Dissertations

This research examines complex clinical decision-making processes in trauma center units of hospitals in terms of the impact of complexity on the medical team involved in the trauma event. The science of complex adaptive systems together with human judgment theories provide important concepts and tools for responding to health care challenges in this century and beyond. Clinical decision-makers in trauma centers are placed in urgent and anxious situations that are increasingly complex, making decision-making and problem-solving processes multifaceted. Under stressful circumstances, physicians must derive their decision-making schemas (―internal models‖ or ―mental models‖) without the benefits of judicious identification, evaluation, and/or …

Assessment Of Neck And Shoulder Muscle Coactivations And The Effect On The Musculoskeletal System, Regina Derria Pope-Ford

Dissertations

Musculoskeletal disorders (MSDs) constitute one of the most important occupational health issues in healthcare workers who are susceptible to upper extremity disorders. Yet MSDs in the healthcare professions have not been studied extensively beyond the lower back. The focus population for this research is the field of dentistry where neck and shoulder disorders have been documented to have a high prevalence. Though quantitative data has been collected, many prior studies have focused on self-reported information. The goal of this research is to provide insight into the inter-relationship of muscles in the upper extremities. One way to accomplish this is to …

Fatigue Characterization Of Fire Resistant Syntactic Foam Core Material, Mohammad Mynul Hossain

Dissertations

Eco-Core is a fire resistant material for sandwich structural application; it was developed at NC A&T State University. The Eco-Core is made of very small volume of phenolic resin and large volume of flyash by a syntactic process. The process development, static mechanical and fracture, fire and toxicity safety and water absorption properties and the design of sandwich structural panels with Eco-Core was established and published in the literature. One of the important properties is needed for application in transportation vehicles is the fatigue performance under different stress states. Fatigue data are not available even for general syntactic foams. The …

Quantitative Analyses Of Acceptable Noise Level For Air Conduction Listening, Bankole K. Fasanya

Dissertations

This study was conducted to develop quantitative models for Acceptable Noise Level (ANL) under air conduction (AC) listening conditions. Experimental results on the effects of frequency bandwidths on ANL under two listening conditions involving earphones and loudspeaker (sound field) with high and low frequencies and babble noise and white noise revealed: (a) there are statistically significant interactions among the background noise types, the background noise frequency bandwidths and signal source; (b) background noise and noise frequency bandwidths have effects on listener discriminability bias toward the noise and the signal intensity; (c) different listening conditions had different ANL thresholds; and (d) …

An Augmented Interaction Strategy For Designing Human-Machine Interfaces For Hydraulic Excavators, Joseph Akyeampong

Dissertations

Lack of adequate information feedback and work visibility, and fatigue due to repetition have been identified as the major usability gaps in the human-machine interface (HMI) design of modern hydraulic excavators that subject operators to undue mental and physical workload, resulting in poor performance. To address these gaps, this work proposed an innovative interaction strategy, termed “augmented interaction”, for enhancing the usability of the hydraulic excavator. Augmented interaction involves the embodiment of heads-up display and coordinated control schemes into an efficient, effective and safe HMI. Augmented interaction was demonstrated using a framework consisting of three phases: Design, Implementation/Visualization, and Evaluation …

Fitness Proportionate Niching: Harnessing The Power Of Evolutionary Algorithms For Evolving Cooperative Populations And Dynamic Clustering, Abrham Tibebu Workineh

Dissertations

Evolutionary algorithms work on the notion of "best fit will survive" criteria. This makes evolving a cooperative and diverse population in a competing environment via evolutionary algorithms a challenging task. Analogies to species interactions in natural ecological systems have been used to develop methods for maintaining diversity in a population. One such area that mimics species interactions in natural systems is the use of niching. Niching methods extend the application of EAs to areas that seeks to embrace multiple solutions to a given problem. The conventional fitness sharing technique has limitations when the multimodal fitness landscape has unequal peaks. Higher …

Tropical Cyclone Intensity Estimation Using Temporal And Spatial Features From Satellite Data, Gholamreza Fetanat Haghighi

Dissertations

Accurate intensity estimation of tropical cyclones (TC) is an important topic of research due to its economic impact and public safety concerns. An accurate measure of the current wind strength is necessary to accurately predict TC intensity. We have developed and tested automated method to estimate TC intensity based on the existing historical satellite images alone. The Hurricane Satellite data (HURSAT-B1) is used to develop the algorithm, which focuses on the North Atlantic from 1978-2009. The algorithm is trained and validated using aircraft reconnaissance-based data. Here, the data is restricted to include only fixes that are over water and are …

A Novel Approach To Intelligent Navigation Of A Mobile Robot In A Dynamic And Cluttered Indoor Environment, Daniel Opoku

Dissertations

The need and rationale for improved solutions to indoor robot navigation is increasingly driven by the influx of domestic and industrial mobile robots into the market. This research has developed and implemented a novel navigation technique for a mobile robot operating in a cluttered and dynamic indoor environment. It divides the indoor navigation problem into three distinct but interrelated parts, namely, localization, mapping and path planning. The localization part has been addressed using dead-reckoning (odometry). A least squares numerical approach has been used to calibrate the odometer parameters to minimize the effect of systematic errors on the performance, and an …

Computational Material Modeling For Mechanical Properties Prediction And A Methodology For Mie Gruneisen Equation Of State Characterization Via Molecular/Nano Scale Cementitious Material Constituents, Ahmed Mohamed

Dissertations

Cementitious materials have complex hierarchical structures with random features that range from nanometer (nm) to millimeter (mm) scale. Processes occurring at the nanometer scale affect the performance at larger length scales. The present work employs molecular dynamics (MD) simulations as the computational modeling methodology to predict mechanical properties for both hydrated and unhydrated cementitious materials at the molecular/nano scale level. A detailed study on the effect of increasing MD simulation cell size, dynamics time duration on the predicted mechanical properties was performed. Further studies focused on understanding the effect of higher thermodynamic pressure states on predicted …

Gravure Printability Of Indium Tin Oxide Nanoparticles On Glass And Pet Films For Applications In Printed Electronics, Dania Awni Alsaid

Dissertations

The advancements in the field of solution processable electro-active materials and their ability to be printed on different substrates have led to the evolution of printed electronics. In this field, electronic components are manufactured with conventional printing methods. Transparent electrodes made from indium tin oxide (ITO) are part of many electronic devices. Currently in industry, highly conductive ITO films are prepared by sputtering. The sputtering and then patterning of ITO films is a sophisticated process that consumes high energy, generates waste and produces films with limited flexibility. Therefore, there is a need to investigate processing methods for creating ITO films …

Optimizing Feeder Bus Network Based On Access Mode Shifts, Zhaodong Huang

Dissertations

The methodology introduced in this dissertation is to optimally find a feeder bus network in a suburban area for an existing rail system that connects the suburban area with the Central Business District (CBD). The objective is to minimize the total cost, including user and supplier costs. Three major access modes (walk, feeder bus, and auto) for the rail station are considered and the cost for all modes makes up the user cost. The supplier cost comes from the operating cost of the feeder bus network. The decision variables include the structure of the feeder bus network, service frequencies, and …

Blind Recognition Of Analog Modulation Schemes For Software Defined Radio, Haifeng Xiao

Dissertations

With the emergence of software defined radios (SDRs), an adaptive receiver is needed that can configure various parameters, such as carrier frequency, bandwidth, symbol timing, and signal to noise ratio (SNR), and automatically identify modulation schemes. In this dissertation research, several fundamental SDR tasks for analog modulations are investigated, since analog radios are often used by civil government agencies and some unconventional military forces. Hence, the detection and recognition of "old technology" analog modulations remain an important task both for civil and military electronic support systems and for notional cognitive radios.

In this dissertation, a Cyclostationarity-Based Decision Tree classifier is …

Graphene-Coated Substrates For Biochemical And Optoelectronic Applications, Amrita Banerjee

Dissertations

Graphene - monolayer or a few layers of graphite -- has proven to possess remarkable properties: large thermal conductivity, mechanical robustness, two-dimensional ultra large electronic mobility, chemical inertness and biochemical compatibility. Realization of some applications has been impeded by lack of a large area deposition method. By using a novel methodology to deposit graphene on solid and perforated substrates, various optoelectronic and biochemical elements have been demonstrated in this thesis: (1) graphene based transistors were fabricated and their characteristics were assessed. The mobility for such transistors exceeded 5000 cm2/V·s, much larger than their silicon based counterparts. Such attribute opens up …

High Aspect Ratio Electrodes For High Yield Electroporation Of Cells, Anil B. Shrirao

Dissertations

Electroporation is a widely used process in cell biology studies. It uses an electric field to create pores on the cell membrane in order to either insert exogenous molecules inside the cells or disrupt the cell membrane to kill the cells. Current micro-fluidic electroporation devices use the planar electrodes situated at the bottom of a microchannel. These planar electrodes i) require a high voltage and ii) generate a nonuniform electric field which result in low yield of the electroporation. The standard silicon microfabrication technologies are not suitable to fabricate non-planar electrodes required to increase the yield of electroporation.

In this …

Inkjet Printability Of Electronic Materials Important To The Manufacture Of Fully Printed Otfts, Sooman Lim

Dissertations

In this study, the inkjet printability of materials important to fabricating OTFTs was researched. In order to understand the jetting evolution of inkjet printed inks, simulations were performed with a nano copper and nano particle silver ink. To predict the inkjettability of the nano copper ink, Z and Oh numbers at different temperatures were determined. The results from the simulation studies were compared to experimental results obtained using a Dimatix inkjet printer. For the semiconductor ink, the inkjet printability of two organic semiconductors, P2TDC17FT4 (poly[(3,7-diheptadecylthieno[3,2-b]thieno[2',3':4,5]thieno[2,3-d]thiophene-2,6-diyl)[2,2'-bithiophene]-5,5'-diyl] dissolved in 1,2-dichlorobenzene and P3HT (poly-3 hexylthiophene) were compared to determine the relationship between drop …

Adaptive Security-Aware Scheduling For Packet Switched Networks Using Real-Time Multi-Agent Systems, Ma'en Saleh Saleh

Dissertations

Conventional real-time scheduling algorithms are in care of timing constraints; they don’t pay any attention to enhance or optimize the real-time packet’s security performance. In this work, we propose an adaptive security-aware scheduling with congestion control mechanism for packet switching networks using real-time agentbased systems. The proposed system combines the functionality of real-time scheduling with the security service enhancement, where the real-time scheduling unit uses the differentiated-earliest-deadline-first (Diff-EDF) scheduler, while the security service enhancement scheme adopts a congestion control mechanism based on a resource estimation methodology.

The security service enhancement unit was designed based on two models: singlelayer and weighted …

Design, Modeling And Fabrication Of Shear Mode Bulk Acoustic Wave Sensor As A Potential Biosensor, Chi-Jung Cheng

Dissertations

There has been an increasing interest in development of thin film bulk acoustic wave resonator (FBAR) devices for chemical and biological sensing applications in the environmental and biomedical industries. The zinc oxide (ZnO) thin film based FBAR devices provides attractive advantages, such as high resonant frequency, small size, and rapid response. Typically, the ZnO-based FBAR devices are operated in the longitudinal wave mode where the ZnO crystallites are perpendicular to the substrate. In gaseous environments, the longitudinal mode FBAR device provides high sensitivity for mass sensing. However, the longitudinal wave mode is adversely affected when used in liquid environments because …

A Discriminative Imaging-Based Framework For Road Sign Condition Assessment Using Local Features And Svm Classifiers, Jafar Jameel Abukhait

Dissertations

Transportation departments are required to monitor the condition of road signs through appropriate condition assessment mechanisms to improve road safety and keep drivers properly informed. Typically, these mechanisms include visual inspection or specialized equipment such as retroreflectometers. These methods are costly, tedious, and risky since they need direct contact with road signs. Efforts to use emerging computer vision techniques for the assessment of road signs condition combined with the availability of road data inventories are allowing the automation of these processes, thus easing the inspection process, reducing costs of equipment, and decreasing the risks associated with the need for maintenance …

Driver Behavior Classification And Lateral Control For Automobile Safety Systems, Jing Yang

Dissertations

Advanced driver assistance systems (ADAS) have been developed to help drivers maintain stability, improve road safety, and avoid potential collision. The data acquisition equipment that can be used to measure the state and parameter information of the vehicle may not be available for a standard passenger car due to economical and technical limitations. This work focuses on developing three technologies (longitudinal tire force estimation, driver behavior classification and lateral control) using low-cost sensors that can be utilized in ADAS.

For the longitudinal tire force estimation, a low cost 1Hz positioning global system (GPS) and a steering angle sensor are used …

Advanced Intelligent Control And Optimization For Cardiac Pacemaker Systems, Wei Shi

Dissertations

Since cardiovascular diseases are major causes of morbidity and mortality in the developed countries and the number one cause of death in the United States, their accurate diagnosis and effective treatment via advanced cardiac pacemaker systems have become very important. Intelligent control and optimization of the pacemakers are significant research subjects. Serious but infrequently occurring arrhythmias are difficult to diagnose. The use of electrocardiogram (ECG) waveform only cannot exactly distinguish between deadly abnormalities and temporary arrhythmias. Thus, this work develops a new method based on frequency entrainment to analyze pole-zero characteristics of the phase error between abnormal ECG and entrained …

Investigation Of The Fracture Phenomena During The Milling Process Of Inorganic Particulates And Brittle Fracture Of Polymer Composites Using Fractal Theory, Zheng Qian

Dissertations

This dissertation investigates the applicability and usefulness of applying Fractal mathematics and to the fracture of brittle particulates in Fluid Energy Mill devices, and in particular quantifying the resulting power law particle size distributions, examining the Surface Fractal Dimension of milled particulates, and relating the Izod Impact Strength values of composites of polypropylene and Calcium carbonate particulates which are large un-milled, small milled, as well as small and produced by the simultaneous milling and coating with nano-silica to the Surface Fractal Dimension of the impact fracture surfaces.

First, the dissertation examines the behavior of un-coated and micron-sized wax pre-coated particulates …

The Incorporation Of Electrohydrodynamics And Other Modifications Into A Dry Spinning Model To Develop A Theoretical Framework For Electrospinning, Yuki Imura

Dissertations

The objective of this research was the development of a mathematical model of the electrospinning process using dry spinning modeling principles as a basis. This model is directed at the identification of parameters which influence final fiber characteristics, e.g., solvent concentration, temperature, spin line tension, and electric field. Preliminary computer simulations were performed; however, the generated data was inconclusive and was determined to be due in part to the complexity of the modeled system and the subsequent computational difficulties encountered. Although a comprehensive computational model of the electrospinning process has not yet been demonstrated, the theoretical development that was undertaken …

Virtual Reality Visual Feedback And Its Effect On Brain Excitability, Soha Saleh

Dissertations

This dissertation examines manipulation of visual feedback in virtual reality (VR) to increase excitability of distinct neural networks in the sensorimotor cortex. The objective is to explore neural responses to visual feedback of motor activities performed in complex virtual environments during functional magnetic resonance imaging (fMRI), and to identify sensory manipulations that could further optimize VR rehabilitation of persons with hemiparesis. In addition, the effects of VR therapy on brain reorganization are investigated. An MRI-compatible VR system is used to provide subjects with online visual feedback of their hand movement. First, the author develops a protocol to analyze variability in …