Engineering Commons^™

Speciation Of Gaseous Oxidized Mercury Molecules Relevant To Atmospheric And Combustion Environments, Francisco J. Guzman

Dissertations

Mercury is a pervasive and highly toxic environmental pollutant. Major anthropogenic sources of mercury emissions include artisanal gold mining, cement production, and combustion of coal. These sources release mostly gaseous elemental mercury (GEM), which upon entering the atmosphere can travel long distances before depositing to environmental waters and landforms. The deposition of GEM is relatively slow, but becomes greatly accelerated when GEM is converted to gaseous oxidized mercury (GOM) because the latter has significantly higher water solubility and lower volatility. Modeling GOM deposition requires the knowledge of its molecular identities, which are poorly known because ultra-trace (tens to hundreds part …

Interventions Of Waterjet Technology In Skin Incisions, Nadi Atalla

Dissertations

This research explores the use of waterjet (WJ) technology in performing skin incisions. The study defines the analytical relationships between the skin properties and the operating parameters of the WJ which include the skin thickness, its elastic modulus, the WJ pressure, the nozzle’s orifice diameter, its stand-off distance and the traverse speed of the WJ as well as the duration of applying the WJ pressure. An analytical model is developed to measure the depth incision of the skin, the water pressure and the water velocity, while using a WJ. Systemization and optimization models that determine the optimal operating parameters levels …

Epitaxial Growth Of Iii-Nitride Nanostructures And Their Optoelectronic Applications, Moab Rajan Philip

Dissertations

Light-emitting diodes (LEDs) using III-nitride nanowire heterostructures have been intensively studied as promising candidates for future phosphor-free solid-state lighting and full-color displays. Compared to conventional GaN-based planar LEDs, III-nitride nanowire LEDs exhibit numerous advantages including greatly reduced dislocation densities, polarization fields, and quantum-confined Stark effect due to the effective lateral stress relaxation, promising high efficiency full-color LEDs. Beside these advantages, however, several factors have been identified as the limiting factors for further enhancing the nanowire LED quantum efficiency and light output power. Some of the most probable causes have been identified as due to the lack of carrier confinement in …

N8- Polynitrogen Stabilized On Carbon-Based Supports As Metal-Free Electrocatalyst For Oxygen Reduction Reaction In Fuel Cells, Zhenhua Yao

Dissertations

The sluggish oxygen reduction reaction (ORR) kinetics at the cathode is one of the key factors limiting the performance of polymer electrolyte membrane fuel cell (PEMFC). Platinum-based materials are the most widely studied catalysts for this ORR reaction while their large-scale practical application in fuel cells is hindered due to their scarcity and low stability. Therefore, highly active, low cost and robust non-Pt catalysts are being developed to overcome the drawbacks. Recently, a novel polynitrogen N8- (PN) stabilized on multiwall carbon nanotube (MWNT) was synthesized under ambient condition for the first time by our group and demonstrated high ORR activities. …

Surface-Enhanced Raman Detection Of Glucose On Several Novel Substrates For Biosensing Applications, Laila Saad Alqarni

Dissertations

The small normal Raman cross-section of glucose is considered to be a major challenge for its detection by Surface Enhanced Raman Spectroscopy (SERS) for medical applications. These applications include blood glucose level monitoring of diabetic patients and evaluation of patients with other medical conditions, since glucose is a marker for many human diseases. This dissertation focuses on Surface-Enhanced Raman Scattering primarily for the detection of glucose. Some experiments also are carried out for the detection of the corresponding enzyme glucose oxidase that is used in electrochemical glucose sensors and in biofuel cells. This project explores the possibility of utilizing Surface …

Workload Allocation In Mobile Edge Computing Empowered Internet Of Things, Qiang Fan

Dissertations

In the past few years, a tremendous number of smart devices and objects, such as smart phones, wearable devices, industrial and utility components, are equipped with sensors to sense the real-time physical information from the environment. Hence, Internet of Things (IoT) is introduced, where various smart devices are connected with each other via the internet and empowered with data analytics. Owing to the high volume and fast velocity of data streams generated by IoT devices, the cloud that can provision flexible and efficient computing resources is employed as a smart "brain" to process and store the big data generated from …

Fouling And Aging In Membrane Filtration : Hybrid Afm-Based Characterization, Modelling And Reactive Membrane Design, Wanyi Fu

Dissertations

Membrane filtration has been extensively used in water and wastewater treatment, desalination, dairy making, and biomass/water separation. However, membrane fouling, aging and insufficient removal efficiency for dissolved organic matters remain major challenges for wider industrial applications. In order to tackle these challenges, this doctoral dissertation investigates mechanisms of membrane fouling and development of antifouling membrane filtration technologies. Specifically, four major research areas are explored: (i) nanoscale physicochemical characterization of the chemically modified polymeric membranes; (ii) quantitative modelling between membrane properties and membrane fouling and defouling kinetics; (iii) development of quantitative structure-activity relationships for membranes that undergo thermal and chemical aging …

Design And Measurement Of A Millimeter-Wave 2d Beam Switching Planar Antenna Array, Benjamin Horwath

Engineering Ph.D. Theses

A millimeter-wave 2-D beam switching microstrip patch antenna array excited by a 4x4 substrate integrated waveguide (SIW) Modified Butler Matrix is designed and experimentally evaluated in this thesis. A novel architecture is introduced for the Butler Matrix feed network to give designers a choice for phase shifter location to pursue a smaller circuit area. In addition, it enables the designer to control the BM phased outputs for achieving a set of desired 2-D beam directions, e.g., ϕ₀=45°, 135°, 225°, and 315° at θ₀=45°, with a passive beam switching network for a given array geometry. Full-wave simulation …

Engineered Excipients Via Dry Particle Coating, Liang Chen

Dissertations

Excipients with good flowability, bulk density as well as compaction properties are desired for use in tableting since they play important roles in formulation development and processing, including, handling, mixing, feeding and compaction. However, it is often difficult to manufacture excipients that simultaneously possess all three desirable properties, particularly if their size is fine. In addition, it is desirable that the excipients promote direct compression of poorly compactable fine cohesive drug powders at sufficiently high drug loading, and not just achieve the desired high functional properties in placebo formulations. This dissertation aims to developed engineered excipients towards this unmet industry …

Enzyme-Assisted Development Of Hydrogels As Medical Materials With Injectable, Biodegradable And Biocompatible Properties, Yung-Hao Tsou

Dissertations

Hydrogels were first discovered in the year 1960 by Wichterle and Lim [1], and in the following decades, they have been widely studied because of their unique characteristics including their hydrophilic nature, biocompatibility, and capacity to mimic the extracellular matrix (ECM). Hydrogels based on natural or synthetic polymers have continued to be of interest for tissue engineering and drug delivery due to their ability to encapsulate living cells and control the release rate of drugs or other bioactive molecules such as pharmaceutical proteins.

In the first part of this dissertation, dopant-free photoluminescent hydrogels formed in situ by crosslinking of biocompatible …

Temporal And Functional Cortical Aspects Related To Mirror Visual Feedback During Target-Directed Movement In Healthy And Stroke Individuals, Maryam Rohafza

Dissertations

Stroke is the leading cause of disability in the United States (American Heart Association, American Stroke Association) affecting 800,000 individuals annually (i.e., one person every 45 seconds). Therapy for stroke often uses repetitive task practice, which is difficult to perform for patients due to impairment. Mirror visual feedback (MVF) based rehabilitation uses the effect of observing the mirror reflection of volitional movement of one limb, to activate visuomotor brain areas that process movement of the opposite limb. In persons with hemiplegia due to stroke, exercising the less affected limb while observing its reflection, perceived by them as the motion of …

Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl

PRC-Affiliated Research

Various additive manufacturing processes are being evaluated to reduce the time and cost for fabrication of low volume, complex, and multifunctional assemblies. This study evaluated two direct energy deposition processes for the fabrication of large bi-metallic structures. The materials evaluated were Inconel 625 and copper alloy C18150, which are used in various high heat flux applications. Inconel was deposited onto the C18150 substrate using blown powder and wire-fed processes. Complete bonding was obtained in both processes and the resulting interfaces were evaluated using microscopy and indentation testing. Differences were observed in the interface region suggesting the kinetic energy of the …

Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl

PRC-Affiliated Research

Various additive manufacturing processes are being evaluated to reduce the time and cost for fabrication of low volume, complex, and multifunctional assemblies. This study evaluated two direct energy deposition processes for the fabrication of large bi-metallic structures. The materials evaluated were Inconel 625 and copper alloy C18150, which are used in various high heat flux applications. Inconel was deposited onto the C18150 substrate using blown powder and wire-fed processes. Complete bonding was obtained in both processes and the resulting interfaces were evaluated using microscopy and indentation testing. Differences were observed in the interface region suggesting the kinetic energy of the …

Characteristics Of Bi-Metallic Interfaces Formed During Direct Energy Deposition Additive Manufacturing Processing, Ryan Anderson, Jordan Terrel, Judy Schneider, Sean Thompson, Paul Gradl

PRC-Affiliated Research

Various additive manufacturing processes are being evaluated to reduce the time and cost for fabrication of low volume, complex, and multifunctional assemblies. This study evaluated two direct energy deposition processes for the fabrication of large bi-metallic structures. The materials evaluated were Inconel 625 and copper alloy C18150, which are used in various high heat flux applications. Inconel was deposited onto the C18150 substrate using blown powder and wire-fed processes. Complete bonding was obtained in both processes and the resulting interfaces were evaluated using microscopy and indentation testing. Differences were observed in the interface region suggesting the kinetic energy of the …

Stress Shielding In Cemented Hip Implants Assessed From Computed Tomography, Bharadwaj Cheruvu, Indresh Venkatarayappa, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Background: Aseptic loosening is the major cause of revisions for hip replacement. This mode of failure is often caused by stress shielding. Stress shielding in the femur occurs when some of the loads are taken by the prosthesis and shielded from going to the bone. There is little information regarding the stress shielding among cemented hip implants. Purpose: The purpose of this study is to investigate the effect of stress shielding on the proximal femur with a femoral prosthesis. Methods: A patient had undergone open reduction and internal fixation (ORIF) due to a comminuted reversed oblique fracture of the right …

Design And Implementation Of An Automated Oil Distribution System For A Homogenizer Machine In Gea Mechanical Equipment – Niro Soavi, Luca Gandolfi

Theses

This thesis shows the steps that have been followed and done in order to improve a critical operation of a technological process of the GEA Mechanical Equipment. The critical operation was the filling with different types of oils the homogenizing machine because it was characterized by a lot of inefficiencies and, in particular, by huge risks for job security. These critical issues gave the opportunity and the chance to realize a project in order to give a process optimization and security improvement.

After having faced all the aspects and steps needed for this project, it has been realized a system …

Mechanics Of Binder-Particle Interactions In Composite Battery Electrodes, Richard Johnson

Theses

A study into the particle level mechanics of polymer binder and active material used in composite lithium-ion batteries (LIB) has been conducted. Silicon is highly sought after material that can be used as an active material in a composite anode. Its high theoretical capacity can result in batteries that can store more energy than current LIBs, but high volume expansion of Si during charge/discharge cycles leads to rapid capacity fade and poor cyclic life. Understanding the stress that is generated in the binder and the active material due to the volume expansion has not been fully understood. In this study …

Multiframe Coded Computation For Distributed Uplink Channel Decoding, Brinell F. Monteiro

Theses

The latest 5G technology in wireless communication has led to an increasing demand for higher data rates and low latencies. The overall latency of the system in a cloud radio access network is greatly affected by the decoding latency in the uplink channel. Various proposed solutions suggest using network function virtualization (NFV). NFV is the process of decoupling the network functions from hardware appliances. This provides the exibility to implement distributed computing and network coding to effectively reduce the decoding latency and improve the reliability of the system. To ensure the system is cost effective, commercial off the shelf (COTS) …

Vergence Eye Movement Parameters For Pre/Post-Obvat And Sham Therapy On Binocularly Normal Controls, Joel V. Rajah

Theses

Vergence is the disjunctive movement of the eyes to maintain single binocular vision. Vergence eye movements are necessary to maintain the object of interest on the fovea of each eye as an individual looks from one object to another. Recent studies show that office based vergence/accommodative therapy (OBVAT) is an effective treatment for the binocular dysfunction known as convergence insufficiency. This study was performed to investigate the changes in oculomotor parameters parameter data for pre- and post-therapy subjects who are binocularly normal controls. A haploscope was used to collect eye movement data pre- and post-therapy. The analysis of the eye …

The Use Of Electrical Resistance Tomography To Determine The Minimum Agitation Speed For Solids Suspension In Stirred Tank Reactors, Baran Teoman

Theses

Njs, the minimum agitation speed needed to just suspend all the solid particles in a solid-liquid mixture stirred in an agitated vessel, is a critical parameter to properly operate industrial tanks in a large number of industrial operations. As a result, a significant literature on Njs is available. The oldest and the most common method to measure Njs experimentally is that of Zwietering’s (Chem. Eng. Sci., 1958, 8, 244-253), where Njs can be visually obtained by determining when the solids stay at the bottom of the tank for no more than 1-2 seconds before being swept away. Although this has …

Tomato Puree Convective Heat Transfer Simulation Using Boussinesq Approximation, Matteo Fabbri

Theses

With the advance of new technologies, the food industries are requiring systems that allow to produce the desired products with faster rates at cheaper costs. In this case, the study was initiated with the purpose to better understand what happens inside a package containing tomato puree when this is heated above 343 K in a tunnel pasteurizer. If the fluid must reach the thermal and microbiological condition of “pasteurization”, the system must guarantee that the temperature (around 343° Kelvin) is kept for a certain time allowing to pasteurize even the cooler package’s fluid-particle. The faster the system can heat the …

Information Technology News, Georgia Southern University

Information Technology: News & Publications (2012-2023)

• IT Internship -- Southeast Bulloch Middle School

Blind Source Separation Using Dictionary Learning Over Time-Varying Channels, Anushreya Ghosh

Theses

Distributed sensors observe radio frequency (RF) sources over flat-fading channels. The activity pattern is sparse and intermittent in the sense that while the number of latent sources may be larger than the number of sensors, only a few of them may be active at any particular time instant. It is further assumed that the source activity is modeled by a Hidden Markov Model. In previous work, the Blind Source Separation (BSS) problem solved for stationary channels using Dictionary Learning (DL). This thesis studies the effect of time-varying channels on the performance of DL algorithms. The performance metric is the probability …

An Electrical Matlab Model Of Plasma Electrolytic Oxidation, Huize Xue

Theses

Plasma Electrolytic Oxidation (PEO), a part of Plasma electrolytic Deposition (PED), has been developing for surface modification of metallic materials in the past 20 years. During PEO process, sample always connect with anode of DC power source, under high temperature, accelerating process of oxidation reaction to from an average and dense oxidation film. A general passage, Plasma electrolysis for surface engineering, written by A.L. Yerokhin, X. Nie gives us a trend of what happened during PEO process but did not determine specific material and value. Linxin Zhu’s Development of PEO invent a new boiling system and investigated relationship between surface …

Glass Transition Temperature Of Particles For Drug Delivery, Yiqing Yang

Theses

Drug delivery plays an important role in targeted therapies and nanoparticles which can be used as drug carriers and it’s a frequently researched topic. Poly(lactic-co-glycolic acid) (PLGA), a highly biocompatible polymer, has been used as a drug delivery vehicle in many studies. One of the challenges facing drug delivery particles is the problem of burst release which is when a large amount of the drug is suddenly released from the particle once it is placed in the body. This is generally undesirable as usually a slow and controlled release is preferred. The glass transition temperature has an effect on drug …

Monitoring Of Cure State Through The Use Of Microwaves, David Judd, Frank Gramling, Reza Zoughi, Mohammad Tayeb Ahmad Ghasr

Electrical and Computer Engineering Faculty Research & Creative Works

A method of manufacturing a tire is provided that includes curing the tire (10) in a curing press (12) and applying microwave energy at a given frequency band into the tire. The interaction between the microwave energy and the tire is monitored to obtain a complex reflection coefficient. A root-mean-squared error is calculated using the measured complex reflection coefficient and a reference reflection coefficient. The reference reflection coefficient is from a fully cured tire made from the same material as the tire. Continuous monitoring of the interaction takes place to obtain the complex reflection coefficient along …

Effect Of Specimen Thicknesses On Water Absorption And Flexural Strength Of Cfrp Laminates Subjected To Water Or Alkaline Solution Immersion, Xue Zhang, Yanlei Wang, Baolin Wan, Gaochuang Cai, Yuan Qu

Civil and Environmental Engineering Faculty Research and Publications

In this paper, an experimental research was undertaken to investigate the effect of specimen thicknesses on water absorptions and flexural strengths of wet lay-up CFRP laminates subjected to distilled water or alkaline solution immersion up to 180 days. Test results showed that the water uptake and flexural strength retention of CFRP laminates were significantly affected by the adopted specimen thickness. For the same aging time, the water uptake of CFRP laminates decreased in the early stage of immersion and increased in the later stage of immersion with the increase of specimen thickness. Meanwhile, the flexural strength retention generally increased as …

College Of Engineering News, Georgia Southern University

College of Engineering & Computing: News & Publications (2010-2023)

• 9 Electrical & Computer Engineering students presented 34 research topics (posters) at IEEE's SoutheastCon.
• Georgia Southern was also represented by three robotic hardware competition teams.

Confucian Robot Ethics, Qin Zhu, Tom Williams, Ruchen Wen

Computer Ethics - Philosophical Enquiry (CEPE) Proceedings

In the literature of artificial moral agents (AMAs), most work is influenced by either deontological or utilitarian frameworks. It has also been widely acknowledged that these Western “rule-based” ethical theories have encountered both philosophical and computing challenges. To tackle these challenges, this paper explores a non-Western, role-based, Confucian approach to robot ethics. In this paper, we start by providing a short introduction to some theoretical fundamentals of Confucian ethics. Then, we discuss some very preliminary ideas for constructing a Confucian approach to robot ethics. Lastly, we briefly share a couple of empirical studies our research group has recently conducted that …

Responding To Some Challenges Posed By The Re-Identification Of Anonymized Personal Data, Herman T. Tavani, Frances S. Grodzinsky

Computer Ethics - Philosophical Enquiry (CEPE) Proceedings

In this paper, we examine a cluster of ethical controversies generated by the re-identification of anonymized personal data in the context of big data analytics, with particular attention to the implications for personal privacy. Our paper is organized into two main parts. Part One examines some ethical problems involving re-identification of personally identifiable information (PII) in large data sets. Part Two begins with a brief description of Moor and Weckert’s Dynamic Ethics (DE) and Nissenbaum’s Contextual Integrity (CI) Frameworks. We then investigate whether these frameworks, used together, can provide us with a more robust scheme for analyzing privacy concerns that …