Engineering Commons^™

Normal-Strength And High-Strength Concrete Columns Under Cyclic Axial Load And Biaxial Moment, Mehdi Zarei

Dissertations

The technique of using Carbon Fiber Reinforced Polymer (CFRP) materials to repair and strengthen various concrete members has become popular in the structural retrofitting field as an effective way to enhance the strength and ductility of concrete members due to its superior mechanical properties. In this study a method was introduced to study the behavior of concrete columns with and without CFRP jackets under constant axial load and variable lateral load. The lateral load was applied monotonically and cyclically. To predict the behavior of concrete columns under monotonic and cyclic compressive loadings, a computer code was developed to produce the …

Experimental And Theoretical Evaluation Of In-Depth Damage Distribution In Sawn Silicon Wafers, Srinivasamurthy Devayajanam

Dissertations

As-sawn silicon wafers have surface damage that needs to be removed before any further processing into solar cells. This damage distribution can vary with cutting parameters such as wire size, slurry particle/diamond grit size, and wire usage. To date, there is no simple way to measure the degree of damage, damage depth, and damage distribution. But, this information is needed by the wafer manufacturers as well as solar cell manufacturers.

A technique based on sequential etching of silicon wafers and minority carrier lifetime (τ_eff) measurements is used to determine damage depth. In this technique, samples are sequentially etched …

Plasticity Of The Cortical Representation Of Finger Extensors Induced By Paired Associative Stimulation, Ian Anthony Gerard Lafond

Dissertations

This dissertation first explored associative plasticity of the human motor cortical representation with the use of noninvasive transcranial magnetic stimulation (TMS) paired with peripheral electrical stimulation. Paired Associative Stimulation (PAS) has grown in popularity because of its potential clinical applications. PAS techniques are used in combination with electromyography (EMG) measurements to study cortical excitability and features of hand movement. This work focuses on a cohesive approach to answer central questions about: the ideal mechanism to facilitate cortical plasticity via PAS, the interaction between the behavior performed and type of stimulation delivered to the targeted cortical network and the effects of …

Measuring The Effectiveness Of Software-Based Training To Improve The Spatial Visualization Skills Of Students In Stem Disciplines In Higher Education Institutions, Peter Cole

Dissertations

This research investigates how software can be used to teach spatial skills leading to greater success in Science, Technology, Engineering, and Mathematical (STEM) fields. Existing research indicates that spatial skills can be taught and that good spatial skills are common to people who succeed in STEM fields. In this work, a software-only testing system with a direct targeted, training intervention module was implemented to measure and teach spatial skills using mental rotations, which are believed to be one of the most significant indicators of success in STEM fields. Spatial skills were tested using a standardized and validated test that measures …

Forecasting Bike Rental Demand Using New York Citi Bike Data, Wen Wang

Dissertations

The idea of this project is from a Kaggle competition “Bike Sharing Demand”① which provides dataset of Capital Bikeshare in Washington D.C. and asked to combine historical usage patterns with weather data in order to forecast bike rental demand. This dissertation will extend this work, working with a broader range of project not only just focusing on the phrase of model building but all phases of KDD (Knowledge Discovery in Databases). This dissertation focuses on Citi Bike which is one of the biggest bike share projects in the world, collects Citi Bike data, weather data and holiday data from three …

An Evaluation Of Gamification To Assess Students’ Learning On Their Understanding Of First Year Computer Science Programming Module, Daniel Gebremichael

Dissertations

This research examines the use of gamification to develop an assessment tool, to assess students’ learning of a first year computer science module. The students’ undertaking of the first semester Programming and Algorithms module in 2015 were assessed on their knowledge of the programming language Python. The incorporation of gamification when assessing students can have various potential benefits. The research aims to identify these benefits and issues. Assessments and games have almost opposite effects on opinions on people, as games are usually expected to have an entertainment value but this is not the case for assessments. The research examines if …

How Do Teachers And Students Perceive The Utility Of Blackboard As A Distance Learning Platform? (Case Study From Taibah University, Saudi Arabia), Suad Alaofi

Dissertations

This research explores the role of Knowledge Management within the education field with a specific focus on the use of Learning Management Systems in the Distance Learning (e-learning) process. The aim of this study is to thoroughly examine how teachers and students perceive the utility of the Blackboard system as a distance learning platform. To achieve this, the study conducted qualitative interviews and quantitative questionnaire surveys with the teachers and students of Taibah University, Saudi Arabia. Questions in both data collection tools were geared towards gaining insight about how these two groups of Blackboard users view its usefulness as a …

Identifying Market Indicators And Content Quality From A Financial Micro-Blog Platform, Siobhán Mcnamara

Dissertations

Investment platforms and discussion platforms have come to change the face of finance. The stock market is open to both professional and non-professional investors via online financial channels. Information too comes via a shared domain as both professionals and non-professionals log onto online communication platforms to share, search and discuss market trends. Due to their growing role in finance, understanding online communities has become the focus of much stock market research. Determining who is influential in a network, how information spreads and what translates to buy or sell decision is potentially very lucrative. In this research paper a dataset from …

Predicting Intake Of Applications For First Registration In The Property Registration Authority, Orlaith Mernagh

Dissertations

The motivation for this dissertation is rooted in a real business need. The Property Registration Authority is the state organisation tasked with maintaining a register of land ownership on the island of Ireland. The PRA currently faces a series of challenges; a high level of staff retiring and the inherent loss of knowledge associated with this trend, a lack of recruitment in recent years and a large increase in lodgement of applications for first registration as a result of legislation. The organisation therefore requires a reliable system for predicting future intake. Prior to this project, there has also been a …

Effects Of Expected Service Life Exposures On The Functional Properties And Impact Performance Of An American Football Helmet Outer Shell Material, David E. Krzeminski

Dissertations

The purpose of this dissertation is to gain a greater scientific understanding of the changes in functional material properties and impact performance of an American football helmet outer shell material under expected service life exposures. The research goals are to (i) quantify chemical, physical, thermal, and mechanical degradation of an American football outer shell material under expected environmental conditions and (ii) develop a linear drop test impact protocol to employ expected on-field impact conditions to American football helmet components and a plaque-foam (i.e., shell-liner) surrogate. Overall, a step-wise progression of analysis was demonstrated to concurrently quantify and understand changes in …

Hybrid Aryl-Ether-Ketone And Hyperbranched Epoxy Networks, John Misasi

Dissertations

In this dissertation, relationships between chemical structures, cure kinetics and network architectures are correlated to bulk mechanical properties for novel, hybrid epoxy-amine networks. The work is split into two primary sections: the first is the synthesis and characterization of multifunctional glassy networks based on aryl-ether-ketone diamine curatives, while the second is based on the synthesis and characterization of hyperbranched epoxy polymers and their resulting networks.

Three aryl-ether-ketone (AEK) diamines of increasing molecular weights were synthesized and used to cure 4,4’-tetraglycidylether of diaminodiphenylmethane (TGDDM); the resulting networks were compared to 4,4’-diaminodiphenyl sulfone cured TGDDM. Architectural differences were created by varying cure …

Polyacrylonitrile Copolymers: Effects Of Molecular Weight, Polydispersity, Composition, And Sequencing On Thermal Ring-Closing Stabilization, Jeremy D. Moskowitz

Dissertations

Controlled polyacrylonitrile (PAN)-based carbon fiber precursors with defined molecular weights, polydispersities, compositions, and architectures have been prepared for their study on thermal ring-closing stabilization behavior. PAN and its copolymers of number average molecular weights exceeding 170,000 g/mol were successfully synthesized via low temperature reversible addition-fragmentation chain transfer (RAFT) polymerization. RAFT polymerizations of PAN-based precursors were compared to conventional free radical solution polymerizations with a focus on the effects of molecular weight and polydispersity on structural evolution and cyclization efficiency. When RAFT polymerization was extended to copolymers, it was found that RAFT copolymers achieved greater cyclization intensities and improved thermal stability …

Development Of Dual-Cure Hybrid Polybenzoxazine Thermosets, Jananee Narayanan Sivakami

Dissertations

Polybenzoxazines are potential high performance thermoset replacements for traditional phenolic resins that can undergo an autocatalytic, thermally initiated ring - opening polymerization, and possess superior processing advantages including excellent shelf-life stability, zero volatile loss and limited volumetric shrinkage. The simplistic monomer synthesis and availability of a wide variety of inexpensive starting materials allows enormous molecular design flexibility for accessing a wide range of tailorable material properties for targeted applications. Despite the fact, once fully cured, benzoxazines are difficult to handle due to their inherent brittleness, leaving a very little scope for any modifications. The motivation of this dissertation is directed …

Face Recognition With Multi-Stage Matching Algorithms, Xianming Chen

Dissertations

For every face recognition method, the primary goal is to achieve higher recognition accuracy and spend less computational costs. However, as the gallery size increases, especially when one probe image corresponds to only one training image, face recognition becomes more and more challenging. First, a larger gallery size requires more computational costs and memory usage. Meanwhile, that the large gallery sizes degrade the recognition accuracy becomes an even more significant problem to be solved.

A coarse parallel algorithm that equally divides training images and probe images into multiple processors is proposed to deal with the large computational costs and huge …

Studying The Optimum Design Of Automotive Thermoelectric Air Conditioning, Alaa Attar

Dissertations

The remarkable amount of research being conducted on thermoelectrics gives the impression that this technology will have a bright future in power generation and temperature control systems. At the present time, thermoelectrics is applied widely for temperature control, but has not yet replaced conventional air-conditioning systems due to its lower performance. Currently, approximately 10% of annual vehicle fuel consumption corresponds to the air-conditioning system used to cool the vehicle cabin. Conventional air-conditioning systems cool the entire cabin; however, about 73% of a vehicle’s mileage occurs while the driver is the only occupant. These facts indicate the need for a single …

Numerical Simulation And Modeling Of Combustion In Scramjets, Ryan James Clark

Dissertations

In the last fifteen years the development of a viable scramjet has quickly approached the following long term goals: responsive sub-orbital space access; long-range, prompt global strike; and high-speed transportation. Nonetheless, there are significant challenges that need to be resolved. These challenges include high skin friction drag and high heat transfer rates, inherent to vehicles in sustained, hypersonic flight. Another challenge is sustaining combustion. Numerical simulation and modeling was performed to provide insight into reducing skin friction drag and sustaining combustion.

Numerical simulation was used to investigate boundary layer combustion, which has been shown to reduce skin friction drag. The …

Application Of Starch-Based Nanoparticle Colloidal Dispersion In Curtain Coating, Ting Chen

Dissertations

In this research, a conventional petro-based latex was partially replaced with a biobased latex in a curtain coating. A common petro-based rheology modifier used in curtain coatings, which is relatively costly and difficult to disperse, was also replaced with two inorganic rheology modifiers. The influence of these materials on coating rheology and curtain stability was thoroughly examined.

In the rheological study, the interactions between biopolymer nanoparticles and inorganic rheology modifiers were found to improve the rheological properties of the biobased latex coatings. Changes in the rheological properties of the coatings were found to depend on the type of rheology modifier …

Development Of A Capacity Deployment Model For Disrupted Supply Chain Networks, James D. Burns

Dissertations

The increasing complexity of modern supply chains is widely accepted as one of the many drivers of risk that can leave organizations vulnerable to the effects of a disruption. This acceptance has contributed to an emerging interest in Supply Chain Resilience in the literature. Resilient supply chains are able to both resist the effects of a disruption and recover efficiently if the disruption is severe. This new body of literature is still in a formative phase and has thus far focused on defining Supply Chain Resilience, proposing frameworks for its implementation, exploring factors that contribute to resilience, and investigating methods …

Novel Software Defined Radio Architecture With Graphics Processor Acceleration, Lalith Narasimhan

Dissertations

Wireless has become one of the most pervasive core technologies in the modern world. Demand for faster data rates, improved spectrum efficiency, higher system access capacity, seamless protocol integration, improved security and robustness under varying channel environments has led to the resurgence of programmable software defined radio (SDR) as an alternative to traditional ASIC based radios. Future SDR implementations will need support for multiple standards on platforms with multi-Gb/s connectivity, parallel processing and spectrum sensing capabilities. This dissertation implemented key technologies of importance in addressing these issues namely development of cost effective multi-mode reconfigurable SDR and providing a framework to …

Modeling And Experimental Study Of Carbon Dioxide Absorption/Stripping In Gas Liquid Membrane Contactor, Nihmiya Abdul Rahim

Dissertations

Natural gas consists primarily of methane (CH4) but it also contains considerable amounts of contaminating compounds mainly carbon dioxide (CO2). The presence of CO2 reduces the heating value of the gas and due to its acidic character causes several operational problems. Hence the removal of CO2 from natural gas is crucially important. The focus of this research work is to investigate the potential for the energy efficient and effective separation of CO2/CH4 gas mixture via lean solvent and regenerating of the rich solvent through absorption/stripping mechanism taking place in a hollow fiber gas liquid membrane contactor process (GLMC) which combines …

Evaluating The Usability Of The Laboratory Information System (Lis) In Coombe Hospital And Hail Hospital, Fahad Alanazi

Dissertations

Today, with the rapid evolution of technology, there has also been a rapid development of medical software and systems in hospitals. These systems and software are now being used globally in many hospitals by users of different languages and cultures. Governments and private hospitals pay large sums of money to utilise highly efficient technology. When systems are changed or updated, employees often find it difficult to deal with the characteristics of the new systems. Also, behavioral factors, such as the fear of committing simple errors, might affect system performance and prevent the full utilization of the staff potential. In this …

An Understanding Of Student Satisfaction, Lorraine Sweeney

Dissertations

Retention is a challenge for all third level institutions and retention rates remain higher than colleges would like them to be, this has intensified in recent years as participants in higher education has increased and diversified. Third level institutions which would not only benefit from increased fees but also through low cost word of mouth promotion and an enhanced reputation. As such, an important concern for colleges is retaining students and understanding the reasons why students may choose to leave a program. While student satisfaction and retention is a well researched topic there remains questions to be answered in terms …

Semantic Models As Knowledge Repositories For Data Modellers In The Financial Industry, Gary Thompson

Dissertations

Data modellers working in the financial industry are expected to use both technical and business knowledge to transform data into the information required to meet regulatory reporting requirements. This dissertation explores the role that semantic models such as ontologies and concept maps can play in the acquisition of financial and regulatory concepts by data modellers. While there is widespread use of semantic models in the financial industry to specify how information is exchanged between IT systems, there is limited use of these models as knowledge repositories. The objective of this research is to evaluate the use of a semantic model …

An Exploration Of The Use Of Gamification In Agile Software Development, Alan Mcclean

Dissertations

Although Project Management has existed for many millennia, software project management is relatively new. As a discipline, software project management is considered difficult. The reasons for this include that software development is non-deterministic; opaque and delivered under ever-increasing time pressure in a volatile environment. Evolving from Incremental and Iterative Development (IID), Agile methodologies have attempted to address these issues by focusing on frequent delivery; working closely with the customer; being responsive to change and preferring working software to extensive documentation. This focus on delivery rather than documentation has sometimes been misrepresented as no documentation, which has led to a shortfall …

A Novel And Domain-Specific Document Clustering And Topic Aggregation Toolset For A News Organisation, Claire Mcmahon

Dissertations

Large collections of documents are becoming increasingly common in the news gathering industry. A review of the literature shows there is a growing interest in datadriven journalism and specifically that the journalism profession needs better tools to understand and develop actionable knowledge from large document sets. On a daily basis, journalists are tasked with searching a diverse range of document sets including news gathering services, emails, freedom of information requests, court records, government reports, press releases and many other types of generally unstructured documents. Document clustering techniques can help address problems of understanding the ever expanding quantities of documents available …

An Evaluation Of Selection Strategies For Active Learning With Regression, Jack O'Neill

Dissertations

While active learning for classification problems has received considerable attention in recent years, studies on problems of regression are rare. This paper provides a systematic review of the most commonly used selection strategies for active learning within the context of linear regression. The recently developed Exploration Guided Active Learning (EGAL) algorithm, previously deployed within a classification context, is explored as a selection strategy for regression problems. Active learning is demonstrated to significantly improve the learning rate of linear regression models. Experimental results show that a purely diversity-based approach to

Production And Characterization Of Composite Nano/Micro Sized Particles By Rapid Expansion Of Supercritical Solutions (Ress) Co-Precipitation, Beidi He

Dissertations

Nanoscale composites of hexahydro-1, 3, 5-trinitro-1, 3, 5-triazine (RDX) and polymer binders were produced by co-precipitation using rapid expansion of supercritical solutions (RESS). The binders used in this study are poly (vinylidene fluoride-co-hexafluoropropylene) (VDF-HFP22), polystyrene (PS) and 7-amino-4-methyl coumarin (AMC). The RDX/VDF-HFP22 and RDX/PS co-precipitated nanoparticles were characterized by Field Emission Scanning Electron Microscopy (FE-SEM) and Transmission Electron Microscopy (TEM). The average size of produced nanoparticles is ca. 100 nm. TEM analysis of RDX/PS nano-composite shows a core-shell structure with RDX as the core material and the shell consisting of the polymeric binder. X-ray Powder Diffraction (XRPD) analysis …

Hydrodynamics, Dissolution, And Mass Transfer Effects In Different Dissolution Testing Apparatuses And Laboratory Systems, Bing Wang

Dissertations

Dissolution testing apparatuses and shaker flasks agitated by shaker tables are laboratory systems routinely found in many laboratories at most companies and agencies, and especially in pharmaceutical companies. These devices are commonly used in a number of applications, from drug development to quality control. Despite their common use, these systems have not been fully investigated from an engineering perspective in order to understand their operation characteristics. For example, the hydrodynamics of many of these systems have received little attention until relatively recently, and only over the last few years have some of these systems, such as the USP dissolution testing …

On The Selection Of A Good Shape Parameter For Rbf Approximation And Its Application For Solving Pdes, Lei-Hsin Kuo

Dissertations

Meshless methods utilizing Radial Basis Functions~(RBFs) are a numerical method that require no mesh connections within the computational domain. They are useful for solving numerous real-world engineering problems. Over the past decades, after the 1970s, several RBFs have been developed and successfully applied to recover unknown functions and to solve Partial Differential Equations (PDEs).
However, some RBFs, such as Multiquadratic (MQ), Gaussian (GA), and Matern functions, contain a free variable, the shape parameter, c. Because c exerts a strong influence on the accuracy of numerical solutions, much effort has been devoted to developing methods for determining shape parameters which provide …

Novel Stretchable Printed Wearable Sensor For Monitoring Body Movement, Temperature And Electrocardiogram, Along With The Readout Circuit, Ali Eshkeiti

Dissertations

Conformal and stretchable wearable sensors provide vital real time information about individual’s health conditions. In this work, Traditional printing methods are used for fabrication of stretchable and wearable sensors which can be mounted on the human skin for the purpose of health tracking. In addition, screen printing technology was utilized to develop printed and flexible electronic circuit board which can be used as a readout circuit along with fabricated wearable sensors. The dissertation is organized and pursued in three projects.

In the first project, screen printing was used to fabricate multi-layer PCBs using printed deposited materials on three distinct substrates. …