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Full-Text Articles in Engineering

Automatic Image Processing And Conversion To Tactile Graphics, Tyler Ferro Jan 2018

Automatic Image Processing And Conversion To Tactile Graphics, Tyler Ferro

Theses and Dissertations

Graphical information has become a critical method for portraying information for education, work and personal tasks and decisions. Unfortunately there are currently limited means of providing this information to individuals who are blind or visually impaired: alternate text is frequently missing, and accessible tactile diagrams tend to be time consuming to make and require expertise in order for them to be interpretable (which may be costly to the user and/or impossible to get). The aim of this project is to provide an accessible system to automatically generate tactile graphics for those who need to interpret information contained in visual images. …


A Rectenna For 5g Energy Harvesting, Panagiotis Efthymakis Jan 2018

A Rectenna For 5g Energy Harvesting, Panagiotis Efthymakis

Theses and Dissertations

This thesis describes the design of a rectenna that is capable of operating in 5G. 5G’s availability will create the opportunity to harvest energy everywhere in the network’s coverage. This thesis investigates a Rectenna device with a new proposed topology in order to eliminate coupling between input and output lines and increase the rectification efficiency. Moreover, it is designed to charge a rechargeable battery of 3V, 1mA, with a 4.8mm diameter. The current design describes using one antenna for energy harvesting; this could be expanded to use an antenna array, which would increase the input power. This would lead to …


Improving Realtime 3-D Tracking Of High Dose Rate Radiation Source Using A Flat Panel Detector, Leo Uchechukwu Udeji Jan 2018

Improving Realtime 3-D Tracking Of High Dose Rate Radiation Source Using A Flat Panel Detector, Leo Uchechukwu Udeji

Theses and Dissertations

Previous research 1 on this subject tracked the presumed exact path the HDR source would follow in real-time, during breast brachytherapy treatments in other to ensure accurate dose delivery and effectively confirm actual source position. As a continuation, this research has three objectives. Firstly, we will extract information from patient DICOM file which will be used to perform evaluations, then we will establish communication between our C program and the new Varex Paxscan flat panel detector (FPD). Finally, we will try to embed our C codes into a MATLAB graphical user interface (GUI) This research will attempt to improve the …


Exogenous Fniii 12-14 Regulates Tgf-Β1-Induced Markers, Hilmi M. Humeid Jan 2018

Exogenous Fniii 12-14 Regulates Tgf-Β1-Induced Markers, Hilmi M. Humeid

Theses and Dissertations

The extracellular matrix protein Fibronectin (FN) plays an important role in cell contractility, differentiation, growth, adhesion, and migration. The 12th -14th Type III repeats of FN (FNIII 12-14), also referred to as the Heparin-II domain, comprise a highly promiscuous growth factor (GF) binding region. This binding domain aids in cellular signaling initiated from the ECM. Additionally, FN has the ability to assemble into fibrils under certain conditions, mostly observed during cell contractile processes such as those that initiate due to upregulation of Transforming Growth Factor Beta 1 (TGF-β1) [1], [2]. Previous work from our lab has shown that self-assembly of …


Developing A Cyberterrorism Policy: Incorporating Individual Values, Osama Bassam J. Rabie Jan 2018

Developing A Cyberterrorism Policy: Incorporating Individual Values, Osama Bassam J. Rabie

Theses and Dissertations

Preventing cyberterrorism is becoming a necessity for individuals, organizations, and governments. However, current policies focus on technical and managerial aspects without asking for experts and non-experts values and preferences for preventing cyberterrorism. This study employs value focused thinking and public value forum to bare strategic measures and alternatives for complex policy decisions for preventing cyberterrorism. The strategic measures and alternatives are per socio-technical process.


Blockchain Scalability And Security, Tuyet Duong Jan 2018

Blockchain Scalability And Security, Tuyet Duong

Theses and Dissertations

Cryptocurrencies like Bitcoin have proven to be a phenomenal success. The underlying techniques hold huge promise to change the future of financial transactions, and eventually the way people and companies compute, collaborate, and interact. At the same time, the current Bitcoin-like proof-of-work based blockchain systems are facing many challenges. In more detail, a huge amount of energy/electricity is needed for maintaining the Bitcoin blockchain. In addition, their security holds if the majority of the computing power is under the control of honest players. However, this assumption has been seriously challenged recently and Bitcoin-like systems will fail when this assumption is …


Decellularized Matrices Effect On The Adaptive Immune Response, Kegan Sowers Jan 2018

Decellularized Matrices Effect On The Adaptive Immune Response, Kegan Sowers

Theses and Dissertations

Decellularized extracellular matrices have been a growing area of interest in the biomedical engineering fields of tissue engineering and regenerative medicine.As these materials move toward clinical applications, the immune response to these materials will be a driving force toward their success in clinical approaches. Fully digested decellularized matrix constructs derived from porcine liver, muscle and lung were created to test the adaptive immune response. Hydrogel characterization ensured that the materials had relatively similar stiffness levels to reduce variability, and in vitro studies were conducted. Each individual construct as well as a gelatin control were plated with a co-culture of macrophages …


Regulation Of Pituitary Progenitor Differentiation By Β-Catenin, Julie Leann Youngblood Jan 2018

Regulation Of Pituitary Progenitor Differentiation By Β-Catenin, Julie Leann Youngblood

Theses and Dissertations

The pituitary gland is a critical organ that is necessary for many physiological processes, including growth, reproduction, and stress response. These vital processes are regulated through the secretion of pituitary hormones from specialized cell types. Pituitary hormone-producing cells arise from a common pool of pituitary progenitors in the developing Rathke’s pouch, and mutations that disrupt the formation and differentiation of pituitary progenitors often result in hypopituitarism, pituitary adenomas, or craniopharyngiomas. Thus, it is necessary to determine the mechanisms of pituitary development in order to understand the ways in which these congenital defects and tumors develop and disrupt pituitary function. Canonical …


Photoluminescence From Gan Co-Doped With C And Si, Mykhailo Vorobiov Jan 2018

Photoluminescence From Gan Co-Doped With C And Si, Mykhailo Vorobiov

Theses and Dissertations

This thesis devoted to the experimental studies of yellow and blue luminescence (YL and BL relatively) bands in Gallium Nitride samples doped with C and Si. The band BLC was at first observed in the steady-state photoluminescence spectrum under high excitation intensities and discerned from BL1 and BL2 bands appearing in the same region of the spectrum. Using the time-resolved photoluminescence spectrum, we were able to determine the shape of the BLC and its position at 2.87 eV. Internal quantum efficiency of the YL band was estimated to be 90\%. The hole capture coefficient of the BLC …


Novel Topologies Based Rf Filtering Components And Methodologies For Wireless Communication System, Wei Jiang Jan 2018

Novel Topologies Based Rf Filtering Components And Methodologies For Wireless Communication System, Wei Jiang

Theses and Dissertations

Driven by the rapid progress of wireless communication technology in the past several decades, multiple generations of cellular technologies have been developed, deployed, and adopted to provide more convenient communication services to users. Nowadays, the personal hand-held devices, supporting multiple wireless standards, have been a multimedia terminal encompassing elements and functions such as video callers, Internet connectivity, home appliances remote controller, GPS, TV reception, and beyond. In order to accommodate a variety of wireless standards in a single device without imposing a substantial increase in cost and size, current and future RF transceiver front-ends should be designed with more attention. …


Fundamental Aspects Of A Novel Technology For Abatement Of Indoor Allergens, Odell Lendor Glenn Jr. Jan 2018

Fundamental Aspects Of A Novel Technology For Abatement Of Indoor Allergens, Odell Lendor Glenn Jr.

Theses and Dissertations

The overall goal of this research was to develop a novel approach to reduce the potency of certain asthma triggers, namely, proteins produced by pests or pets in indoor environments. The broad hypothesis of the research was that naturally occurring essential oils will demonstrate enhanced denaturing ability. In any indoor environment, allergens are bound to dry dust particles. In this work, the effectiveness of using dry ice and CO2 with potential for essential oils on dry allergenic proteins through CFD modeling and ELISA methods were evaluated.

There are three objectives central to this work. The first objective was to apply …


Hydrothermal Carbonization Of Food Waste For Nutrient Recovery And Reuse, Ifeolu M. Idowu Jan 2018

Hydrothermal Carbonization Of Food Waste For Nutrient Recovery And Reuse, Ifeolu M. Idowu

Theses and Dissertations

Food waste represents a rather large and currently underutilized source of potentially available and reusable nutrients. Laboratory-scale experiments evaluating the hydrothermal carbonization of food wastes collected from restaurants were conducted to understand how changes in feedstock composition and carbonization process conditions influence primary and secondary nutrient fate. Results from this work indicate that at all evaluated reaction times and temperatures, the majority of nitrogen, calcium, and magnesium remain integrated within the solid-phase, while the majority of potassium and sodium reside in the liquid-phase. The fate of phosphorus is dependent on reaction times and temperatures, with solid-phase integration increasing with higher …


Social Engineering Knowledge Measured As A Security Countermeasure, Christopher Artejus Sanders Jan 2018

Social Engineering Knowledge Measured As A Security Countermeasure, Christopher Artejus Sanders

Theses and Dissertations

Social Engineering has become a significant threat to the security of business, government, and academic institutions. As vulnerabilities to social engineering attacks increase, organizations must incorporate risk mitigation strategies to their portfolios of Information Systems Security Countermeasures (ISSC). The goal is to implement mitigation strategies that balance the cost of implementation, the privacy of employees, and the resulting expected costs of social engineering attacks. In this paper we develop an analytical model that calculates the total cost of protection, including the trade-off between the cost of implementing protection strategies and the resulting expected cost of social engineering attacks. We use …


Ontology-Guided Pre-Release Inference Disruption, Mark Stephen Daniels Jan 2018

Ontology-Guided Pre-Release Inference Disruption, Mark Stephen Daniels

Theses and Dissertations

We investigate privacy violations occurring when non-confidential patient data is combined with medical domain ontologies to disclose a patient’s protected health information (PHI). We propose a framework that detects privacy violations and eliminates undesired inferences. Our inference channel removal process is based on controlling the release of the data items that lead to undesired inferences. These data items are either blocked from release or generalized to eliminate the disclosure of the PHI. We show that our method is sound and complete. Soundness means the only inference paths generated logically follow from released data and corresponding domain knowledge. Completeness means we …


Understanding Geopolymerization Process For Enhancement Of Mechanical Properties Of Fly Ash Based-Geopolymer Concrete, Lateef Najeh Assi Jan 2018

Understanding Geopolymerization Process For Enhancement Of Mechanical Properties Of Fly Ash Based-Geopolymer Concrete, Lateef Najeh Assi

Theses and Dissertations

Concrete is a major construction material that is largely made up of cement. Unfortunately, the manufacturing process for the cement currently used to produce concrete releases a great deal of CO2, which endangers the environment. Hence, finding alternatives to ordinary Portland cement is of extreme importance. The intellectual contribution of this dissertation is the development of an improved understanding of the geopolymerization process so that the compressive strength of cement can be maximized while the need for external heating is minimized. The intent is to create a substance to replace commonly used cement without sacrificing other beneficial properties. The first …


The Design, Development, And Evaluation Of A Usable And Privacy-Enhanced Telepresence Interface For Older Adults, Xian Wu Jan 2018

The Design, Development, And Evaluation Of A Usable And Privacy-Enhanced Telepresence Interface For Older Adults, Xian Wu

Theses and Dissertations

Maintaining health and wellness while aging-in-place independently is crucial for older adults. Telepresence technology can be potentially beneficial for this target population to stay socially connected. However, this technology is not specifically designed for older adults. For this target population to adopt such technology successfully, it is important to ensure that they do not experience usability barriers. This research uses HCI/HRI concepts and technology design principles for older adults to design, develop and test telepresence user interfaces (UI). This addresses the following research questions: 1): What are the essential usability and privacy-enhanced features needed to inform the design and development …


Selective Deposition Of Platinum By Strong Electrostatic Adsorption Onto Cobalt- And Iron-Based Catalysts For Fischer-Tropsch Synthesis, Fahad A. Almalki Jan 2018

Selective Deposition Of Platinum By Strong Electrostatic Adsorption Onto Cobalt- And Iron-Based Catalysts For Fischer-Tropsch Synthesis, Fahad A. Almalki

Theses and Dissertations

Cobalt and iron based catalysts are commercially predominant for Fischer-Tropsch synthesis, Co-based catalysts for their stability, activity, and inactivity for the water gas shift reaction and Fe-based catalysts for their cheap cost, high light-olefins and alcohols selectivity, and tolerance to H2/CO ratio. These catalysts are structure sensitive with lower activity at nanoparticle sizes smaller than 6-8 nm. Co-based catalysts exhibit high activity, low CH4 selectivity, and high C5+ selectivity, while Fe-based catalysts are more selective to low-molecular-weight hydrocarbons such as olefins and alcohols. The reducibility of cobalt and iron is another important factor which may be key for improving their …


Assessing Exposure To Occupants In An Indoor Space Due To Expirated Aerosols: Application Of Computational Fluid Dynamics, Firoza Binte Omar Jan 2018

Assessing Exposure To Occupants In An Indoor Space Due To Expirated Aerosols: Application Of Computational Fluid Dynamics, Firoza Binte Omar

Theses and Dissertations

Indoor environment is an important issue for the well-being of the society. In the United States more than 90% people spend their time indoor, indoor air pollution is more culpable than the pollution outside air. Two third of US businesses lose more than $100,000 per year due to workplace related illness. The trend of sharing the work space has an impact on total sick leaves in a company. Infectious particles released by a flu sufferer’s sneezing, coughing or even laughing can be a vital source. A thorough analysis on infectious particles’ transmission and air flow of the space can provide …


Authenticating Users With 3d Passwords Captured By Motion Sensors, Jing Tian Jan 2018

Authenticating Users With 3d Passwords Captured By Motion Sensors, Jing Tian

Theses and Dissertations

Authentication plays a key role in securing various resources including corporate facilities or electronic assets. As the most used authentication scheme, knowledgebased authentication is easy to use but its security is bounded by how much a user can remember. Biometrics-based authentication requires no memorization but ‘resetting’ a biometric password may not always be possible. Thus, we propose study several behavioral biometrics (i.e., mid-air gestures) for authentication which does not have the same privacy or availability concerns as of physiological biometrics.

In this dissertation, we first propose a user-friendly authentication system Kin- Write that allows users to choose arbitrary, short and …


Development Of Novel Models To Study Deep Brain Effects Of Cortical Transcranial Magnetic Stimulation, Farheen Syeda Jan 2018

Development Of Novel Models To Study Deep Brain Effects Of Cortical Transcranial Magnetic Stimulation, Farheen Syeda

Theses and Dissertations

Neurological disorders require varying types and degrees of treatments depending on the symptoms and underlying causes of the disease. Patients suffering from medication-refractory symptoms often undergo further treatment in the form of brain stimulation, e.g. electroconvulsive therapy (ECT), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), or transcranial magnetic stimulation (TMS). These treatments are popular and have been shown to relieve various symptoms for patients with neurological conditions. However, the underlying effects of the stimulation, and subsequently the causes of symptom-relief, are not very well understood. In particular, TMS is a non-invasive brain stimulation therapy which uses time-varying magnetic …


Fault Classification And Location Identification On Electrical Transmission Network Based On Machine Learning Methods, Vidya Venkatesh Jan 2018

Fault Classification And Location Identification On Electrical Transmission Network Based On Machine Learning Methods, Vidya Venkatesh

Theses and Dissertations

Power transmission network is the most important link in the country’s energy system as they carry large amounts of power at high voltages from generators to substations. Modern power system is a complex network and requires high-speed, precise, and reliable protective system. Faults in power system are unavoidable and overhead transmission line faults are generally higher compare to other major components. They not only affect the reliability of the system but also cause widespread impact on the end users. Additionally, the complexity of protecting transmission line configurations increases with as the configurations get more complex. Therefore, prediction of faults (type …


Investigation Into Integrated Free-Form And Precomputational Approaches For Aerostructural Optimization Of Wind Turbine Blades, Ryan Timothy Barrett Jan 2018

Investigation Into Integrated Free-Form And Precomputational Approaches For Aerostructural Optimization Of Wind Turbine Blades, Ryan Timothy Barrett

Theses and Dissertations

A typical approach to optimize wind turbine blades separates the airfoil shape design from the blade planform design. This approach is sequential, where the airfoils along the blade span are pre-selected or optimized and then held constant during the blade planform optimization. In contrast, integrated blade design optimizes the airfoils and the blade planform concurrently and thereby has the potential to reduce cost of energy (COE) more than sequential design. Nevertheless, sequential design is commonly performed because of the ease of precomputation, or the ability to compute the airfoil analyses prior to the blade optimization. This research investigates two integrated …


Mechanical And Material Characterization Of Advanced Materials For Tissue Regeneration, Bailey Kylara Ricketts Jackson Jan 2018

Mechanical And Material Characterization Of Advanced Materials For Tissue Regeneration, Bailey Kylara Ricketts Jackson

Theses and Dissertations

In natural disasters and military deployment operations, injury to long bone can cause extensive damage and be difficult to treat and heal quickly. Explosive devices and trauma often produce long-bone (>2-cm length) wounds that are more complicated than common fractures. Due to the size and complexity of these injuries, they can be difficult to treat in a battlefield environment and take a long time to heal completely and properly. Even after the long healing period, these injuries often require rehabilitation to strengthen the muscles that have weakened in the wounded limb. For military applications especially, these effects can put …


Enhancements In Alginate Microencapsulation Technology & Impacts On Cell Therapy Development, Marwa Belhaj Jan 2018

Enhancements In Alginate Microencapsulation Technology & Impacts On Cell Therapy Development, Marwa Belhaj

Theses and Dissertations

Biodegradable alginate microcapsules (MC) are recently becoming widely used in the biomedical field, and have shown effectiveness as a drug delivery system. Alginate has been used in microencapsulation due to its simple gelling process, biodegradability, excellent biocompatibility, and its stability under in-vivo conditions. Alginate polymer is a natural polysaccharide derived from brown seaweed and has the ability to polymerize rapidly in the presence of cations to form a porous matrix. In order to advance the previous system for efficient protein and peptide delivery, we further lyophilized the peptide-filled microcapsules and we were able to rehydrate, and test them for sustained …


Matrix Stiffness Modulates Mesenchymal Stem Cell Sensitivity To Geometric Asymmetry Signals, Maria Eugenia Piroli Jan 2018

Matrix Stiffness Modulates Mesenchymal Stem Cell Sensitivity To Geometric Asymmetry Signals, Maria Eugenia Piroli

Theses and Dissertations

Human stem cells hold significant potential for the treatment of various diseases. However, their use as a therapy is hampered by the limited understanding of the mechanisms by which stem cells respond to environmental stimuli. Efforts to understand extracellular biophysical cues have demonstrated the critical roles of geometric and mechanical signals in determining the fate of stem cells. The goal of this study was to explore the interplay between cell polarity and matrix stiffness in stem cell lineage specification. We hypothesize that confining cells to asymmetric extracellular matrix (ECM) islands will impart polarity at a single-cell level and result in …


Quantifying Time Retarded Electromagnetic Fields And Their Applications In Transmission Lines, Brandon Thomas Gore Jan 2018

Quantifying Time Retarded Electromagnetic Fields And Their Applications In Transmission Lines, Brandon Thomas Gore

Theses and Dissertations

Modern baseband signaling that facilitates the passing of information over high speed interconnects such as copper twin-ax cable and printed circuit boards supports single line data rates of 100 Gbps. Next generation bandwidth requirements of electrical links are approaching frequencies up to 50 GHz. Yet, signal integrity engineers that analyze these interconnects rely on models with underlying assumptions and limited extensions beyond those proposed in the 19th century to describe per unit length characteristics of Resistance, Inductance, Conductance, and Capacitance (RLGC) for transatlantic telegraph cable. An excluded phenomenon is the time retarded behavior of electromagnetic fields. The aim of this …


Plants As Biofactories To Produce Mammalian Tumor Suppressor Micrornas, John Lachlan Macarthur Jan 2018

Plants As Biofactories To Produce Mammalian Tumor Suppressor Micrornas, John Lachlan Macarthur

Theses and Dissertations

MicroRNAs (miRNAs) are small noncoding single stranded RNAs that are considered master regulators of gene expression. They are also an emerging class of therapeutic agents with significant potential for the prevention and treatment of many diseases, including cancer. Many different forms of cancer are associated with loss or reduced accumulation of one or more miRNAs that function as tumor suppressors. In animal models, restoration of missing tumor suppressor miRNAs prevents the initiation, progression and/or spread of the disease. However, the current absence of an efficient method for delivery of therapeutic miRNAs is a critical barrier to their use. The research …


Novel Wideband Ebg Structures For Isolation Improvement Between Cosite Antennas, Paul John Czeresko Iii Jan 2018

Novel Wideband Ebg Structures For Isolation Improvement Between Cosite Antennas, Paul John Czeresko Iii

Theses and Dissertations

As the number of installed antennas increases on a structure, the available real estate to do so without each antenna interfering with the others diminishes. Electromagnetic band gap (EBG) structures are one way to mitigate this cosite interference with compact antenna installations. While a host of EBG structures and types (3-D, planar etc.) have been proposed and studied historically, it has been found that planar EBG structures tend to provide very narrow bandwidths for both antenna design and cosite interference reduction. This research focuses on the design of EBG structures intended to achieve greater than 20 dB of isolation improvement …


Stabilization Of Silicon And Germanium Based High Capacity Anodes For Lithium Ion Batteries, Kuber Mishra Jan 2018

Stabilization Of Silicon And Germanium Based High Capacity Anodes For Lithium Ion Batteries, Kuber Mishra

Theses and Dissertations

Lithium-ion batteries (LIBs) have been the driver of the widespread application of portable electronics. As the electronic devices have been more powerful and versatile, the pressing demand for higher energy density batteries have led the extensive explorations of novel materials for high capacity electrodes. Despite several breakthroughs in literature, the current state of art LIBs still uses the battery chemistry developed in early 1990s.The keys challenges for switching to other high capacity electrodes have been high cost, non-linear scalability and poorer electrochemical performance. This dissertation focusses on development of high capacity electrodes in order to increase the energy density of …


Impact Of Critical Path Method (Cpm) Of Scheduling On On-Time Completion Of Transportation Projects, Fahim Ahmed Jan 2018

Impact Of Critical Path Method (Cpm) Of Scheduling On On-Time Completion Of Transportation Projects, Fahim Ahmed

Theses and Dissertations

This study addresses the effectiveness of Critical Path Method (CPM) scheduling on project delivery. Specifically, the on-time completion of projects with and without a CPM schedule is explored. The paper uses data from 2,097 South Carolina transportation projects let after February 2008 and substantially completed by August 2015. The delay analysis uses the original contract completion date as well as the completion date adjusted by change orders. Chi-Squared tests are used to examine the relationship between CPM scheduled projects and delayed projects, and t-tests are used to compare the mean delay (in days) between CPM scheduled and unscheduled projects. The …