Engineering Commons^™

Recycling In A Lean Environment, Marylin N. Glass-Hedges

Dissertations

Lean Manufacturing and Green Manufacturing systems co-occur in many manufacturing facilities. This dissertation investigated the relationship between materials recycling—as an important green waste-reduction technique—and lean techniques, and their influence on lean outcomes, specifically 1) if a correlation exists between lean techniques and material recycling, as these two variables also influence lean outcomes; and 2) the mediating effect of materials recycling between lean techniques and lean outcomes. Exploratory factor analysis, confirmatory factor analysis, and structural equation modeling were the chosen statistical analysis methods utilized to explore and confirm the lean techniques and lean outcomes constructs, test the models’ hypotheses and answer …

Control Strategies For Improving The Performance Of Heaving Wave Energy Converters, Mohammed Abdi Jama.

Dissertations

The main objective of this study is to develop control strategies to enhance the performance of single-body heaving wave energy converters (WECs). Maximizing the energy captured from sea waves while respecting the physical and thermal limitations of the WEC is of a paramount importance for any control strategy to be effective. In addition, it is desirable for the controller to be less vulnerable to model uncertainties and external disturbances. A complete wave-to-wire dynamic model has been derived for the heaving WEC. This includes models that describe the system hydrodynamic forces using the linear wave theory and models that describe the …

Implementation Of Traditional Printing Techniques For The Development Of Flexible Printed Sensors, Sai Guruva Reddy Avuthu

Dissertations

Printed electronics has gained a remarkable interest over the past decade for the fabrication of cost efficient electronic devices, with a major focus on the development of flexible sensors. This dissertation focuses on the fabrication of flexible sensors using traditional printing processes such as screen, inkjet and gravure printing.

A flexible organic thin film transistor (OTFT) was successfully fabricated on a polyethylene terephthalate (PET) substrate and employed as a humidity sensor. Aluminum gate electrode was thermally evaporated on PET and UV clear dielectric layer was spin coated. Source and drain silver interdigitated electrodes were screen printed. 6,13-bis(triisopropylsilylethynyl) pentacene, a humidity …

Exploration Of Stimulus Current Energy Reduction And Bifurcation Dynamics In Conductance-Based Neuron Models Using Optimal Control Theory, Michael E. Ellinger

Dissertations

Hodgkin-Huxley type conductance-based models can simulate the effect of time-varying injected stimulus currents on the neuron membrane voltage. The dynamics simulated by these model types enables investigation of the biophysical basis of neuronal activity which is fundamental to higher level function. Broadened understanding the basis of nervous system function could lead to development of effective treatment for related diseases, disorders, and the effects of trauma. In this dissertation, optimal control is used with conductance-based neuron models to develop a "Reduced Energy Input Stimulus Discovery Method." Within the method, an objective function balances two competing criteria: tracking a reference membrane voltage …

Analysis Of Vibroacoustic Properties Of Dimpled Beams Using A Boundary Value Model, Kyle R. Myers

Dissertations

Attention has been given recently to the use of dimples as a means of passively altering the vibroacoustic properties of structures. Because of their geometric complexity, previous studies have modeled dimpled structures using the finite element method. However, the dynamics of dimpled structures are not completely understood. The goal of this study is to provide a better understanding of these structures through the development of a boundary value model (BVM) using Hamilton's Variational Principle. The focus of this study is on dimpled beams, which represent the simplest form of a dimpled structure.

A general model of a beam with N …

New Screening Methodology For Selection Of Polymeric Materials For Transdermal Drug Delivery Devices, Roberto P. Falcone

Dissertations

As medical advances extend the human lifespan, the level of chronic illnesses will increase and thus straining the needs of the health care system that, as a result, governments will need to balance expenses without upsetting national budgets.

Therefore, the selection of a precise and affordable drug delivery technology is seen as the most practical solution for governments, health care professionals, and consumers.

Transdermal drug delivery patches (TDDP) are one of the best economical technologies that are favored by pharmaceutical companies and physicians alike because it offers fewer complications when compared to other delivery technologies. TDDP provides increased efficiency, safety …

High Frequency Field Potentials Of The Cerebellar Cortex, Jonathan David Groth

Dissertations

The cerebellum plays a crucial role in motor coordination along with basal ganglia and the motor areas of the cerebral cortex. Both somatosensory and the cerebro-cerebral pathways bring in massive amounts of neural information to the cerebellum. The output of the cerebellar cortex projects to various motor cortices as well as down to the spinal cord to make its contributions to the motor function.

The origin and function of the field potential oscillations in the cerebellum, especially in the high frequencies, have not been explored sufficiently. The primary objective of this study was to investigate the spatio-temporal characteristics of high …

Accounting For Midblock Pedestrian Activity In The Hcm 2010 Urban Street Segment Analysis, Albert Forde

Dissertations

The Urban Street segment analysis Chapter of the 2010 Highway Capacity Manual (HCM 2010) provides a methodology for analyzing automobile performance on signalized roadway segments within an urban roadway network. The methodology involves applying a platoon dispersion model to: a) predict the vehicle arrival flow profiles at a downstream signalized intersection; b) use the predicted arrivals to compute the proportion of vehicle arrivals on green; and c) subsequently estimate the delay, travel speed and Level of Service (LOS) under which the segment operates. Vehicles arriving during the red interval at a signalized intersection generally accumulate and form a platoon. When …

Optimization Methods For Active And Passive Localization, Nil Garcia

Dissertations

Active and passive localization employing widely distributed sensors is a problem of interest in various fields. In active localization, such as in MIMO radar, transmitters emit signals that are reflected by the targets and collected by the receive sensors, whereas, in passive localization the sensors collect the signals emitted by the sources themselves. This dissertation studies optimization methods for high precision active and passive localization.

In the case of active localization, multiple transmit elements illuminate the targets from different directions. The signals emitted by the transmitters may differ in power and bandwidth. Such resources are often limited and distributed uniformly …

Collaborative Rescheduling Of Flights In A Single Mega-Hub Network, Sufian Ikhmeis

Dissertations

Traditionally, airlines have configured flight operations into a Hub and Spoke network design. Using connecting arrival departure waves at multiple hubs these networks achieve efficient passenger flows. Recently, there has been much growth in the development of global single mega-hub (SMH) flight networks that have a significantly different operating cost structure and schedule design. These are located primarily in the Middle East and are commonly referred to as the ME3. The traditionalist view is that SMH networks are money losers and subsidized by sovereign funds.

This research studies and analyzes SMH networks in an attempt to better understand their flight …

System Design And Performance Analysis Of Asymmetrically And Symmetrically Clipped Optical (Asco)-Ofdm For Im/Dd Optical Wireless Communications, Nan Wu

Dissertations

As the quantity of mobile communication devices, such as cellphones, tablets, and laptops, dramatically increase, the demand for high speed wireless service has been growing. Optical wireless communications (OWCs), which offer unlimited transmission bandwidth, have received a lot of attention and been studied in recent decades. They can be an effective alternative to radio frequency communications (RFCs) for indoor high speed data transmission. Intensity modulation direct detection (IM/DD) is a simple way to realize the transmission of optical wireless signals in an indoor environment. Information data streams are modulated into the intensity of optical carriers and transmitted by light emitting …

Piezoelectric Scaffolds For Osteochondral Defect Repair, Sita Mahalakshmi Damaraju

Dissertations

Osteoarthritis is one of the most prevalent causes of disability affecting nearly 27 million Americans. Osteoarthritis is caused when extensive damage occurs to the articular cartilage later spreading to the underlying subchondral bone, resulting in osteochondral defects. The current clinical therapies aim at regenerating the hyaline cartilage, but instead fibrocartilage forms at the osteochondral defect site, which is inferior in structure and function and fails to integrate with the surrounding tissue. A biomimetic scaffold, which can provide cues similar to the native extracellular matrix, may facilitate osteochondral defect repair. Articular cartilage and bone extracellular matrix have been shown to produce …

Eliciting Knowledge Bases With Defeasible Reasoning: A Comparative Analysis With Machine Learning, Peter Keogh

Dissertations

This thesis compares the ability of an implementation of Defeasible Reasoning (via Argumentation Theory) to model a construct (mental workload) with Machine Learning. In order to perform this comparison a defeasible reasoning system was designed and implemented in software. This software was used to elicit a knowledge base from an expert in an experiment which was then compared with machine learning. The central findings of this thesis were that the knowledge based approach was better at predicting an objective performance measure, time, than machine learning. However, machine learning was better equiped to identify another object measure task membership. The knowledge …

Maturity Of Cloud Application Interoperability Frameworks For Small To Medium Enterprises, John Warde

Dissertations

Cloud computing has many benefits and organisations have bought into the cost effective and elastic solutions provided by major players in the market. However, cloud computing and Cloud Service Providers (CSP) are still evolving, hence there are differences in how customers connect with each provider to the orchestrate application lifecycle management. A lack of standards can create vendor lock-in. This work investigates current research and possible solutions to the vendor lock-in problem through the use of Cloud Interoperability or multi-cloud frameworks. Software developers and organisations can use these frameworks which abstract the differences between CSPs and mitigate vendor lock-in. A …

An Evaluation Of The Use Of Diversity To Improve The Accuracy Of Predicted Ratings In Recommender Systems, Gillian Browne

Dissertations

The diversity; versus accuracy trade off, has become an important area of research within recommender systems as online retailers attempt to better serve their customers and gain a competitive advantage through an improved customer experience. This dissertation attempted to evaluate the use of diversity measures in predictive models as a means of improving predicted ratings. Research literature outlines a number of influencing factors such as personality, taste, mood and social networks in addition to approaches to the diversity challenge post recommendation. A number of models were applied included DecisionStump, Linear Regression, J48 Decision Tree and Naive Bayes. Various evaluation metrics …

Investigating The Relationship Between Organizational Innovation Capability And Firm Performance With Irish Smes, Maryam Bukhamsin

Dissertations

The topic of innovation capability and its relationship with performance has been examined by several previous studies. The purpose of this thesis is to investigate the relationship between innovation capability aspects proposed by the Innovation Value Institute (IVI) and firms’ overall performance. IVI is specialised in developing organizational and innovation capability in order to improve firms’ performance. In addition, this study presents the most important aspects of innovation capability that are directly and positively associated with firms’ overall financial and operational performance. This empirical study was conducted on small- and medium-sized enterprises (SMEs) in Ireland; the data was collected from …

Cure Kinetics, Morphologies, And Mechanical Properties Of Thermoplastic/Mwcnt Modified Multifunctional Glassy Epoxies Prepared Via Continuous Reaction Methods, Xiaole Cheng

Dissertations

The primary goal of this dissertation is to develop a novel continuous reactor method to prepare partially cured epoxy prepolymers for aerospace prepreg applications with the aim of replacing traditional batch reactors. Compared to batch reactors, the continuous reactor is capable of solubilizing and dispersing a broad range of additives including thermoplastic tougheners, stabilizers, nanoparticles and curatives and advancing epoxy molecular weights and viscosities while reducing energy consumption.

In order to prove this concept, polyethersulfone (PES) modified 4, 4’-diaminodiphenylsulfone (44DDS)/tetraglycidyl-4, 4’-diaminodiphenylmethane (TGDDM) epoxy prepolymers were firstly prepared using both continuous reactor and batch reactor methods. Kinetic studies confirmed the chain …

Time Integration Methods Of Fundamental Solutions And Approximate Fundamental Solutions For Nonlinear Elliptic Partial Differential Equations, Corey Leon Jones

Dissertations

A time-dependent method is coupled with the Method of Approximate Particular Solutions (MAPS) of Delta-shaped basis functions, the Method of Fundamental Solutions (MFS), and the Method of Approximate Fundamental Solutions (MAFS) to solve a second order nonlinear elliptic partial differential equation (PDE) on regular and irregular shaped domains. The nonlinear PDE boundary value problem is first transformed into a time-dependent quasilinear problem by introducing a fictitious time. Forward Euler integration is then used to ultimately convert the problem into a sequence of time-dependent linear nonhomogeneous modified Helmholtz boundary value problems on which the superposition principle is applied to split the …

Novel Bioinformatic Approaches For Analyzing Next-Generation Sequencing Data, Yan Peng

Dissertations

In general, DNA reconstruction is deemed as the key of molecular biology since it makes people realize how genotype affects phenotypes. The DNA sequencing technology emerged exactly towards this and has greatly promoted molecular biology’s development. The traditional method, "Sanger," is effective but extremely expensive on a cost-per-base basis. This shortcoming of Sanger method leads to the rapid development of next-generation sequencing technologies. The NGS technologies are widely used by virtue of their low-cost, high-throughput, and fast nature. However, they still face major drawbacks such as huge amounts of data as well as relatively short read length compared with traditional …

Secure And Reliable Routing Protocol For Transmission Data In Wireless Sensor Mesh Networks, Nooh Adel Bany Muhammad

Dissertations

Abstract

Sensor nodes collect data from the physical world then exchange it until it reaches the intended destination. This information can be sensitive, such as battlefield surveillance. Therefore, providing secure and continuous data transmissions among sensor nodes in wireless network environments is crucial. Wireless sensor networks (WSN) have limited resources, limited computation capabilities, and the exchange of data through the air and deployment in accessible areas makes the energy, security, and routing major concerns in WSN. In this research we are looking at security issues for the above reasons. WSN is susceptible to malicious activities such as hacking and physical …

Modeling New Product Success From Component Measures Of Product Advantage: A Model Utilizing Automated Text Classification And Sentiment Analysis, Ashley Nolen Akerman

Dissertations

What attributes of products are most associated with product success from the perspective of the consumer and how is this association affected by the technology level of the product offering? Creating successful new products is an imperative for long term survival for businesses. Past research has focused on the perspectives of manufacturers to understand product attributes that comprise the construct described as product advantage. This study investigated the components of product advantage from the perspective of the consumer and the significance of each component in explaining variance in product success.

A methodology and two classification toolsets were developed for the …

Blind Source Separation For Feature Detection And Segmentation In Ground Penetrating Radar (Gpr) Lmaging Of Concrete Bridge Decks For Nondestructive Condition Assessment, Vincent Krause

Dissertations

Concrete bridge decks require periodic condition assessment and preventive maintenance to extend their useful lifespan. Nondestructive evaluation methods such as Ground Penetrating Radar (GPR) are slowly beginning to replace or complement the manual (visual) assessment of bridge conditions for detecting defects at their early stages. However, GPR scans of bridge decks are frequently cluttered with high amplitude reflections from known parts of the bridge deck, which make the detection of defects’ low amplitude reflections difficult. One such known part is the embedded steel reinforcement bars known as rebar.

This dissertation presents a novel approach to the automated detection of defects …

Modeling Of Environmentally Assisted Fatigue Crack Growth Behavior, Sree Phani Chandar Reddy

Dissertations

The formation of fatigue cracks and their propagation due to cyclic loading in metals have been a concern for more than hundred years. Since fatigue failure were first reported by the railroad industry in 1840s, tremendous progress has been achieved in understanding fatigue behavior of metals. But fatigue damage is still a concern due to its complex dependency on various environmental variable like humidity, temperature, time and corrosive environment. Although numerous theories and models have been proposed in the past, the effects of environment on fatigue crack growth (FCG) is not completely understood. This dissertation aims to shed light on …

Transient Cardiovascular Hemodynamics In A Patient-Specific Arterial System, Jr Rodward Hewlin

Dissertations

The ultimate goal of the present study is to aid in the development of tools to assist in the treatment of cardiovascular disease. Gaining an understanding of hemodynamic parameters for medical implants allow clinicians to have some patient-specific proposals for intervention planning. In the present study a full cardiovascular experimental phantom and digital phantom (CFD model) was fabricated to study: (1) the effects of local hemodynamics on global hemodynamics, (2) the effects of transition from bed-rest to upright position, and (3) transport of dye (drug delivery) in the arterial system. Computational three dimensional (3-D) models (designs A, B, and C) …

Identification Of Employee Engagement Practices Viewed As Critical To Retention: A Cross-Generational Comparison, Sharon R. Floyd

Dissertations

Purpose. The purpose of this study was to identify the employee engagement practices that millennial IT workers perceive as important to retention. The secondary purpose of the study was to determine whether a difference exists between the engagement practices that appeal to millennial IT workers and the engagement practices that appeal to remaining IT working groups, which include the baby boomers and generation X.

Methodology. A quantitative, descriptive, survey-based research method was chosen for this study. The population included information technology workers representing three generations of working adults, including baby boomers, generation Xers, and millennials. The sample included technology workers …

Investigating Correlation Between Availability Of Free Time Facilities For Pupils And Their Educational Achievements While Exploiting Linked Data And Volunteered Geographic Information, Peter Kovar

Dissertations

The advent of Semantic Web as an extension of the current World Wide Web (Web) brings methods and technologies to structure the data, interlink it with other related data and capture its semantics. This holds for new data to be published as well as for the data already on the Web. The interlinking of data led to definition of a linked data paradigm and the Semantic Web allows for creating a Global Linked Data Space. The linked data sets can combine data coming from heterogeneous sources. Using ontologies the meaning in data from different areas of interest can be compared …

Exploring The Impact That Organisational Culture And Structures Have On Knowledge Management Initiatives, Gavin Digan

Dissertations

The project builds on research in the domain of knowledge management, with a literature review covering several aspects of the domain. There is particular emphasis on knowledge management implementations within organisations. Several researchers in the area offer methodologies or strategies for organisations to adopt, when implementing knowledge management initiatives. These options are covered at length in the literature review along with real world case studies on organisations that have implemented knowledge initiatives with varying degrees of success. A key aspect of the research is assessing the impact of organisational culture on knowledge management initiatives. The literature review contains an extensive …

Can Passive Mobile Application Traffic Be Identified Using Machine Learning Techniques, Peter Holland

Dissertations

Mobile phone applications (apps) can generate background traffic when the end-user is not actively using the app. If this background traffic could be accurately identified, network operators could de-prioritise this traffic and free up network bandwidth for priority network traffic. The background app traffic should have IP packet features that could be utilised by a machine learning algorithm to identify app-generated (passive) traffic as opposed to user-generated (active) traffic. Previous research in the area of IP traffic classification focused on classifying high level network traffic types originating on a PC device. This research was concerned with classifying low level app …

Can Wikipedia Article Traffic Statistics Be Used To Verify A Technical Indicator? An Exploration Into The Correlation Between Wikipedia Article Traffic Statistics And The Coppock Technical Indicator., Cormac O'Connor

Dissertations

Recent studies have shown that, through the quantification of Wikipedia Usage Patterns as a result of information gathering, stock market moves can be predicted (Moat et al 2013). There was also research performed to determine the predictive nature of Wikipedia Data to predict movie box office success (Mestyan et al. 2013). The goal of any investor, in order to maximize the return of their investments, is to have an edge over other participants in the markets. Several tools and techniques have been used over the years to fulfil this, some proving to generate a consistent stream of income (Gillen 2012). …

An Open Source Implementation And Evaluation Of A Federated Searching Service Based On File Based Index And Relational Database Index, Alan Liu

Dissertations

One of the greatest challenges in the modern information world is the storage of data and the ability to extract usable knowledge from it, to enable enterprises to gain insight that can be leverage to succeed in the competitive environment. Data is constantly being generated and collected at a rapid pace from users and customers via many sources such as intranet, internet and other smart devices. To effectively use the collected data, knowledge must be extracted from it to allow effective and efficient business planning. While the core challenge of data analytics is to extract hidden non-trivial information form large …