Engineering Commons^™

Influence Of Low Shear And Cyclic Strain On Hyperglycemic Rat Aortic Smooth Muscle Cells: An In Vitro Dynamic Disease Model, Varun Chawla

All Theses

Vascular complications are the leading cause of morbidity and mortality amongst diabetic patients which represent a major proportion of patients undergoing coronary artery revascularization. Major advances in drug eluting stent technologies have reduced the overall rates of restenosis in general however diabetic patients still remain at a high risk thus requiring target lesion revascularization more commonly as compared to non-diabetic cohort. Phenotypic modulation demonstrated by smooth muscle cells is essential for normal wound healing response however is also contributive to initiation and development of various vascular complications including neointimal hyperplasia which ultimately leads to the lumen re-narrowing or restenosis. Hyperglycemia …

Analysis And An Application Of Rf Interferometer, Yongzhi Shao

All Theses

The thesis investigates additive RF interferometer sensing technique, which is highly sensitive compared to other RF sensing methods. First, mathematical descriptions are given to illustrate how the RF interferometer works. Then an analysis of single particle passing over a coplanar waveguide in carrier liquid is presented, which poses as a difficulty to simulation software. The analysis is combined with interferometer mathematical equations and validated by a particle measurement in an interferometer. The interferometer sensitivity is enhanced by incorporating filters as sensing devices and functionally expanded by using the reflection coefficients. In the end, an application of gas measurement with the …

Quantum-Mechanical Calculations Of Actinyl And Europium Sorption To Graphene Oxide, Edward Helvenston

All Theses

Quantum-mechanical calculations were performed to model the interactions of U(VI), Np(V), Pu(VI), and Eu(III) with carboxyl and hydroxyl functional groups of graphene oxide (GO). Models were created for sorption to a single sheet of GO. For U(VI) and Eu(III), models were also created for sorption to two sheets to evaluate the possibility of cation-induced GO aggregation via cation cross-linking of GO sheets. The quantum-mechanical calculations were used to characterize the sorption reactions in terms of energetics and vibrational peak shifts. The calculations performed used Gaussian09 with the B3LYP hybrid functional. Sorption was seen as favorable for all cations considered; the …

Self-Adapting Parallel Framework For Long-Term Object Tracking, Salim Mohammed Ali

All Theses

Object tracking is a crucial field in computer vision that has many uses in human-computer interaction, security and surveillance, video communication and compression, augmented reality, traffic control, etc. Many implementations are introduced in practice, and yet recent methods emphasize on tracking objects adaptively by learning the object’s perspectives and rediscovering it when it becomes untraceable, so that object’s absence problem (in case of occlusion, cluttering or blurring) is resolved. Most of these algorithms have high computational burden on the computational units and need powerful CPUs to attain real-time tracking and high bitrate video processing. These computational units may handle no …

Development And Validation Of An Optically-Based Strain Measuring Orthopaedic Screw For Fracture Fixation Implants, Nakul Ravikumar

All Theses

In the USA over 28 million musculoskeletal injuries are treated annually, including 2 million fracture fixation surgeries (about 0.5% of the population).[1] Treatment of large osseous defects use allografts which have failure rates of up to 25%, and complication rates as high as 30-60%.[2] Fracture fixation usually involves mechanical fixation with rods, plates and/or screws which repair slowly and are susceptible to infection. Implant infection and loosening are serious concerns, but can currently only be measured through expensive instrumented implants, biopsy culture, or radiographs. However, none of these directly quantify implant loading and stability. There is therefore a need for …

Understanding Molecular Interactions Between Proteins And Carbon Nanomaterials, Siva Dasetty

All Theses

Over the past few years there has been a rise in the number of nanomaterials engineered for a wide array of applications because of their unique properties. This rise in the development of engineered nanomaterials (ENMs) and its growing usage has also raised questions about its potential impact on the biological environment. Recent experimental studies suggest that these ENMs could be toxic due to the formation of a protein corona. Therefore, understanding the formation of a protein corona would provide some insights into the toxic behavior of ENMs. This requires understanding the interactions between proteins and ENMs. We employ molecular …

Sensitivity And Precision Analysis Of The Graph Complexity Connectivity Method, Sudarshan Sridhar

All Theses

In the Graph Complexity Connectivity Method (GCCM), twenty nine complexity metrics applied against engineering design graphs are used to create surrogate prediction models of engineering design representations (assembly models and function structures) for given product performance values (assembly time and market value). The performance of these prediction models has been previously assessed solely based on accuracy. In this thesis, the predictive precision of the surrogate models is evaluated in order to assess the GCCM's ability to generate consistent results under the same conditions. The Assembly Model - Assembly Time (AM-AT) prediction model performed the best in terms of both accuracy …

Inertial Focusing Of Particles In Curved Microchannels, Ketaki Joshi

All Theses

Since the beginning of microfluidics, the ability to control motion of particles in microchannels has always been fascinating. Microfluidic techniques such as dielectrophoresis, magnetophoresis rely on externally applied fields to separate particles while others like hydrophoresis and deterministic lateral displacement depend on low Reynolds number operation for particle manipulation. One of these techniques is inertial focusing of particles in microchannels. The particles and channel interact to cause lateral migration of particles to equilibrium positions within channel cross-section in flow regime where inertia and viscosity of fluid are finite. Inertial focusing has wide range of applications in fields of chemical synthesis, …

Primary Flexion Axis Selection In Total Knee Replacements Using Computational Analysis, Nicholas Marais

All Theses

Total knee replacements (TKR) are one of the most frequently implanted medical devices, with over 600,000 procedures performed in the United States in 2012. In order to ensure TKR longevity, wear tests are frequently conducted on these implants prior to patient implantation. Variations in implant geometry, material, and surface treatments are all tested, however, TKR alignment may also play a role in the long-term success of the knee implant. When testing knee designs with complex tibial and femoral geometries it is essential that the implant be aligned as the implant manufacturers intended so as to best represent the function of …

Microcosm Evaluation Of Enhanced Bioremediation For Halogenated Methanes At A Former Industrial Site, Hao Wang

All Theses

Halogenated methanes are among the most frequently encountered contaminants at hazardous waste sites. One such site in California is contaminated with chloroform (CF), carbon tetrachloride (CT), and trichlorofluoromethane (CFC-11). CF, CT and CFC-11 are the main focus of this research; they are present at the California site at concentrations in the mg per liter range and a plume of contaminated groundwater emanating from a source zone is approaching a property boundary, necessitating remediation. Anaerobic bioremediation is one of the technologies under consideration for addressing the source zone and the less concentrated downgradient plume. A microcosm study was performed to evaluate …

Exploring The Potential Impact Of Meditation Intervention On Stroke Trends In The United States., Raj Ambavane

All Theses

Meditation has shown promise in clinical trials in reducing systolic blood pressure, one of the main causes of stroke. We explore the potential impact of expanding meditation intervention on stroke trends in the US. We developed a dynamic population simulation in which the progression of each individual is governed by a micro-simulation model. We calibrated the micro-simulation model for stroke incidence and further validated it by comparing the stroke-related mortality for each age group generated by the model with that observed in the US. We used the population simulation model to estimate the effects of mindfulness meditation intervention on stroke …

Evaluation Of Shiryaev-Roberts Procedure For On-Line Environmental Radiation Monitoring, Mara Watson

All Theses

An on-line radiation monitoring system that simultaneously concentrates and detects radioactivity is needed to detect an accidental leakage from a nuclear waste disposal facility or clandestine nuclear activity. Previous studies have shown that classical control chart methods can be applied to on-line radiation monitoring data to quickly detect these events as they occur; however, Bayesian control chart methods were not included in these studies. This work will evaluate the performance of a Bayesian control chart method, the Shiryaev-Roberts (SR) procedure, compared to classical control chart methods, Shewhart 3-σ and cumulative sum (CUSUM), for use in on-line radiation monitoring of 99Tc …

Comparison Gmm And Svm Classifier For Automatic Speaker Verification, Shamama Afnan

All Theses

The objective of this thesis is to develop automatic text-independent speaker verification systems using unconstrained telephone conversational speech. We began by performing a Gaussian Mixture Model Likelihood ratio verification task in speaker independent system as described by MIT Lincoln Lab. We next introduced a speaker dependent verification system based on speaker dependent thresholds. We then implemented the same system applying Support Vector Machine. In SVM, we used polynomial kernels and radial basis function kernels and compared the performance. For training and testing the system, we used low-level spectral features. Finally, we provided a performance assessment of these systems using the …

Bioprinting As A Tool To Evaluate Interactions Of Cancerous And Noncancerous Cells, Holly Jordan

All Theses

Cancer is becoming one the leading causes of death worldwide, and in particular, breast cancer, which is the second highest cause of cancer death for women. Approximately 12 percent of US women will develop invasive breast cancer, and about 40,000 of US women will die from breast cancer in 2015. With better detection and treatment options, breast cancer death has been decreasing over the past two decades. Despite declining rates in breast cancer death, cancer progression is not well understood. There are many studies focused on cancer, but in situ cancer studies are often hard to reproduce and can even …

Microcosm Evaluation Of Enhanced Bioremediation For An Industrial Site Contaminated With Chlorinated Ethenes, Chlorinated Benzenes, And Benzene, Christopher Moss

All Theses

Groundwater contaminants at an industrial site in South Carolina include tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (cDCE), vinyl chloride (VC), 1,2,4-trichlorobenzene (1,2,4-TCB), 1,2-dichlorobenzene (1,2-DCB), 1,4-dichlorobenzene (1,4-DCB), chlorobenzene (CB), and benzene. The source areas at the site include a tank farm area, a grease trap area, the former wastewater lagoons (WWTP) and the former oil retention pond (ORP). A microcosm evaluation was preformed to determine the potential for bioremediation to treat the organic contaminants in the four source areas (within the saturated zone) and in a downgradient portion of the groundwater plume. The objectives were to evaluate 1) anaerobic treatment at the …

Using Connected Vehicle Technology To Implement A Pay For Priority System At Signalized Intersections, Melissa Gende

All Theses

This research evaluated a mixed vehicle environment that included connected and non-connected vehicles in which connected vehicles (CV) were allowed to pay a small fee to request priority at a signalized intersection, similar to a transit signal priority system. Connected vehicles with signal priority were simulated with penetration levels ranging from 10% to 100% as well as with various priority directions (all directions, major street movements in both directions, and major street movements in the direction of highest flow) being allowed to request priority. These scenarios were compared to optimized signal timings to determine the effectiveness of the technology in …

Biodegradation Of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) Using Photosynthetic Bacteria, Sarah Galloway

All Theses

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is an emerging contaminant according to the Environmental Protection Agency (EPA). RDX was introduced as a secondary explosive during World War II. It is still used in many explosive such as hand grenades. RDX enters the environment mostly through the manufacturing process or from the use of explosives. RDX is a suspected carcinogen and can also affect the nervous system of humans. Therefore, RDX has become a chemical of concern across many United States military bases and open and closed manufacturing plants. The goal of this research was to evaluate the biodegradation of RDX via two phototrophic bacteria: …

Design Of Cab Suspensions And Semi-Active Seat Damping Control Strategies For Tractor Semi-Trailers, Judhajit Roy

All Dissertations

This thesis uses a high fidelity vertical plane ride model of the tractor semi-trailer to study the effect of different cab design configurations and semi-active seat damper control strategies on the driver’s ride comfort.

The secondary suspensions of a tractor have been an area of particular interest because of the considerable ride comfort improvements they provide. A gap exists in the current engineering domain of an easily configurable high fidelity low computational cost simulation tool to analyze the ride of a tractor semi-trailer. A 15 degree of freedom model of the tractor semi-trailer was used to develop a simulation tool …

Manipulation Of The Electrical Double Layer For Control And Sensing In A Solid State Nanopore, Samuel L. Bearden

All Dissertations

Nanopores have been explored with the goal of achieving non-functionalized, sub-molecular sensors, primarily with the purpose of producing fast, low-cost DNA sequencers. Because of the nanoscale volume within the nanopore structure, it is possible to isolate individual molecular and sub-molecular analytes. Nanopore DNA sequencing has remained elusive due to high noise levels and the challenge of obtaining single-nucleotide resolution. However, the complete electrical double layer within the nanopore is a key feature of fluid-nanopore interaction and has been neglected in previous studies. By exploring interactions with the electrical double layer in various nanopore systems, we characterize the material, electrical, and …

Measurement Of Older And Younger Drivers' Selected Seat Position Within Their Personal Vehicles To Influence Recommended Practices For Meeting Safety Needs Of Drivers, Shayne Kelly Mcconomy

All Dissertations

The objective of this research was to measure and understand the preferred seat position and posture of older drivers and younger drivers within their personal vehicles to influence recommended practices for meeting the safety needs of all drivers.Currently, the United States is experiencing an ageing population, whereby in 2020 nearly 40 million people over the age of 65 will be licensed drivers. In addition, crash reports show that older drivers are over represented in vehicle fatality statistics, once adjusted for vehicle miles traveled. The increased fatality rate of older drivers has been attributed to a combination of increased fragility of …

Accuracy, Efficiency, And Parallelism In Network Target Coordination Optimization, Meng Xu

All Dissertations

The optimal design task of complex engineering systems requires knowledge in various domains. It is thus often split into smaller parts and assigned to different design teams with specialized backgrounds. Decomposition based optimization is a multidisciplinary design optimization (MDO) technique that models and improves this process by partitioning the whole design optimization task into many manageable sub-problems. These sub-problems can be treated separately and a coordination strategy is employed to coordinate their couplings and drive their individual solutions to a consistent overall optimum. Many methods have been proposed in the literature, applying mathematical theories in nonlinear programming to decomposition based …

Technical And Economic Assessment Of Perovskite Solar Cells For Large Scale Manufacturing, Amir A. Asif, Rajendra Singh, Githin F. Alapatt

Publications

In this paper, we have carried out detailed technical and economic assessment of perovskite solar cells for large scale manufacturing. For ultra-small area of the order of 0.1 cm², efficiency of 20% or so are reported. However, for area of 25 cm², the efficiency is about 10%. Based on the photovoltaic module manufacturing requirements of no constraint on the supply of raw materials, low variability of every key process and process-induced defects, low cost of manufacturing, prospects for further cost reduction in the future, green manufacturing, and long-term reliability, there are absolutely no prospects of manufacturing …

Microcosm Study Of 1,4-Dioxane Biotransformation, Philip Arve

All Theses

1,4-Dioxane is an emerging groundwater contaminant and probable human carcinogen with considerable potential remediation costs due to its hydrophilic and recalcitrant nature. Commonly occurring with 1,1,1-trichloroethane (1,1,1-TCA) plumes due to its application as a solvent stabilizer, 1,4-dioxane is also used in industrial lubricants and occurs as an impurity in numerous personal care products. Current treatment strategies to treat dioxane contamination include advanced oxidation processes and biological treatment, though only aerobic paths of biodegradation are currently understood. Laboratory and field studies have indicated the possible inhibitory effects of 1,1,1-TCA and its abiotically transformed daughter product, 1,1-dichloroethene (1,1-DCE) on the aerobic biodegradation …

Estimation Of Pcb Contamination In The Twelve Mile Creek Arm Of Lake Hartwell Using Gis And Statistical Techniques, Arjun Bharadwaj

All Theses

The Lake Hartwell and its Twelve Mile Creek watershed were contaminated with polychlorinated biphenyls (PCBs), mainly Aroclor 1016 and 1254, which resulted in a designation as a Superfund site. The Twelve Mile Creek arm is the most heavily contaminated portion of the lake. The Twelve Mile Creek arm of Lake Hartwell was placed on the National Priorities List (NPL) in the year 1990. In the Record of Decision (ROD) by the EPA in 1994, natural attenuation, primarily through burial by uncontaminated sediment, was declared as the chosen remedy to reach the EPA recommended level of 1 µg/g. Several studies have …

A Method For The Characterization And Selection Of Compliant Joints, Ronald George Saleeby

All Theses

A compliant joint is a connection between two bodies that derives its movement from the deflection of flexible members rather than rigid connections, like traditional joints. Compliant joints have potential advantages that include longer part life, reduction of parts in assemblies, and reduced wear. Traditional compliant mechanism design methodologies have limitations involving the burden of necessary knowledge required to satisfactorily use them. The method presented in this thesis was developed to provide compliant joint design solutions independent of the traditional methods of compliant joint design by allowing the selection of compliant joints from a repository. The repository is populated by …

Continuum Robots For Space Applications Based On Layer-Jamming Scales With Stiffness Capability, Jessie Lee C. Santiago

All Theses

Continuum robots, which have continuous mechanical structures comparable to the flexibility in elephant trunks and octopus arms, have been primarily geared toward the medical and defense communities. In space, however, NASA projects these robots to have a place in irregular inspection routines. The inherent compliance and bending of these continuum arms are especially suitable for inspection in obstructed spaces to ensure proper equipment functionality. In this paper, we propose a new solution that improves on the functionality of previous continuum robots, via a novel mechanical scaly layer-jamming design. Layer-jamming assisted continuum arms have previously required pneumatic sources for actuation, which …

Design Of Reliable And Sustainable Wireless Sensor Networks: Challenges, Protocols And Case Studies, Fan Yang

All Dissertations

Integrated with the function of sensing, processing, and wireless communication, wireless sensors are attracting strong interest for a variety of monitoring and control applications. Wireless sensor networks (WSNs) have been deployed for industrial and remote monitoring purposes. As energy shortage is a worldwide problem, more attention has been placed on incorporating energy harvesting devices in WSNs. The main objective of this research is to systematically study the design principles and technical approaches to address three key challenges in designing reliable and sustainable WSNs; namely, communication reliability, operation with extremely low and dynamic power sources, and multi-tier network architecture. Mathematical throughput …

Engineering Hospital Discharge Instructions: An Eye-Tracking Based Study, Haley Marie Vaigneur

All Theses

With new healthcare reform initiatives, (e.g., the Patient Protection and Affordable Care Act) hospitals have additional requirements to reduce avoidable readmissions. This results in identifying the needs for improving the hospital discharge process, improving care transitions and discharge instructions, and increasing overall patient health literacy. In terms of discharge instructions, one of the most influential factors to patients' understanding and compliance with their prescribed health regimen is the document's readability. The study goal is to examine how adjusting the discharge instructions' reading level and using human factors design guidelines can influence a novice user's ability to read, comprehend, and recall …

Assessment Of Bore-Cone Taper Junctions In Explanted Modular Total Hip Replacements, Christine Margaret Stamer

All Theses

For people with chronic hip pain due to arthritis or other conditions, a total hip replacement (THR) is a common procedure used to eliminate the pain. Due to the natural variation in patient anatomy, THR prostheses are becoming increasingly more modular to allow for a more customized initial replacement and for an easier revision if needed in the future. Currently, THR prostheses routinely have modular femoral heads to provide surgeons with intraoperative flexibility. This modularity allows the surgeons to maintain the proper leg length and restore hip biomechanics for the patient and insert the components more easily and precisely. Modular …

Computational Modeling Of Alternating Current Potential Drop Measurement For Crack Detection Of Multi-Functional Ceramic Coated Structures, Simha Sandeep Rao

All Theses

Non-destructive testing and evaluation (NDT&E) is a set of techniques commonly used to evaluate a material for the presence of any flaws without actually degrading the material itself. The Alternating Current Potential Drop (ACPD) test method is one of the NDT surface methods used to determine the electrically insulating defects beneath the surface by injection of currents in the structure and measurement of the resulting voltage difference between two or more points on the surface. The presence of defects generally increases the resistance of the structure and hence causes the drop of measured voltage. The inversion of this data can …