Engineering Commons^™

Twelve Mile Creek Channel Morphology, Substrate Composition, And The Macroinvertebrate Community Changes Resulting From Multiple Dam Removals, Patricia Whitener

All Theses

Dam removal is gaining global attention as a potential restoration tool for impacted rivers. As the practice of dam removal increases, physical, chemical and biological monitoring before and after dam removal is essential to our understanding of the ecological consequences of this type of disturbance. Under the Lake Hartwell Restoration and Compensation Determination Plan, two dams (>9 m height) were removed from the Twelve Mile Creek watershed (170 km2) in Pickens county, South Carolina. To assess the short term impacts of dam removal on the Twelve Mile Creek ecosystem we conducted biomonitoring of macroinvertebrate species and surveys of river …

Scratch Damage Evolution On Metals In Total Joint Replacements, Caleb Eljach

All Theses

The goal of total joint replacement (TJR) is to replace nonfunctioning joint components and relieve pain, improve quality of life, and to improve joint function. Although TJR is a successful procedure, more than 54,000 knee revisions occur each year due to factors, such as wear, loosening, infection, fracture, instability, and patient related factors (Ranawat, 2010). TJRs consist of components typically composed of polyethylene and a metallic counterface (Navarro, 2008). The sliding contact that occurs between the metal and polyethylene components has been well studied and is shown to produce both surface damage and wear of the implant components (Barbour, 1997; …

Dissolved Carbon Dioxide For Scale Removal In Reverse Osmosis, Erin Partlan

All Theses

Membrane fouling is a major operational issue in reverse osmosis (RO) desalination plants. In particular, plants treating brackish groundwater can encounter troublesome inorganic scales, including carbonates, sulfates, and silicates. A novel cleaning method is proposed to remove inorganic scales from fouled RO membranes usinag dissolved CO ₂ . As CO₂ molecules encounter membrane foulants, the surfaces serve as nucleation sites for small bubbles to form and shear off foulants. Dissolved CO₂ solutions were prepared by bubbling CO₂ gas into water held in a pressure vessel. Gas dissolution was confirmed by enhanced exit velocities for water containing CO …

Adaptive Transmission For Ofdm, Michael Juang

All Theses

To respond to dynamic channel conditions caused by fading, shadowing, and other time-varying disturbances, orthogonal frequency division multiplexing (OFDM) packet radio systems should adapt transmission parameters on a packet-by-packet basis to maintain or improve performance over the channel. For this to be possible, there are three key ideas that must be addressed: first, how to determine the subchannel conditions; second, which transmission parameters should be adapted; and third, how to adapt those parameters intelligently. In this thesis, we propose a procedure for determining relative subchannel quality without using any traditional channel measurements. Instead, statistics derived solely from subcarrier error counts …

Improvements In The Process Of Biohydrogen Production By Thermotoga Neapolitana, Louis Hill

All Theses

The production of biological hydrogen is an important process for the future of sustainability and alternative energies. Thermotoga neapolitana is a hyperthermophilic bacterium that produces H ₂ , CO₂ and acetate via fermentation. The goal of the research was to investigate the sustainable production of H₂ gas using waste agricultural feedstocks, recycled water and a simplified N₂ sparging method technique. A limited sparging method was developed which includes 1 minute of N₂ gas sparging of the reactor headspace and 90 minutes of idle reaction time for cysteine-HCl to react with dissolved oxygen prior to inoculation. This …

Evaluating The Predictive Capability Of Numerical Models Considering Robustness To Non-Probabilistic Uncertianty In The Input Parameters, Parker Shields

All Theses

The paradigm of model evaluation is challenged by compensations between various forms of errors and uncertainties that are inherent to the model development process due to, for instance, imprecise model input parameters, scarcity of experimental data and lack of knowledge regarding an accurate mathematical representation of the system. When calibrating model input parameters based on fidelity to experiments, such compensations lead to non-unique solutions. In turn, the existence of non-unique solutions makes the selection and use of one `best' numerical model risky. Therefore, it becomes necessary to evaluate model performance based not only on the fidelity of the predictions to …

Functional Stroke Recovery Through Tissue Engineered Niche Neural Constructs, Natasha Topoluk

All Theses

According to the Centers for Disease Control and Prevention, stroke is statistically responsible for 1 in every 19 deaths of American citizens.5 Stroke is the leading cause of permanent disability due to the fact that it compromises both cellular and tissue components of the brain, leading to the formation of a physical void within the tissue. Current research approaches address the cellular component by injecting stem cells into this void; however, extremely low cell engraftment, high injected cell death, and overall no matrix regeneration are observed. Additionally, these stem cells do not remain committed to a neural lineage. We propose …

Analyzing Requirement Type Influence On Generated Solutions, Emily Worinkeng

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Several ideation methods are available and used by engineering designers to enable the generation of alternative designs [1]. However, there has been little work done to understand the role that the design problem given to participants plays in the ideation process. The contribution of this research is found through the proposed guidelines with respect to the type of requirements to include as part of the design problem in order to achieve the desired quantity, quality, novelty, and variety of solutions during the early stages of the design process. This work is the first attempt at analyzing the effect of requirement …

A Study Of Gallery Method To Increase Idea Quality In Conceptual Design, Liz Mathew

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The objective of this research is to evaluate whether gallery method increases idea quality in conceptual design for engineering design problems. The gallery method is a group ideation process which allows individuals to first generate ideas individually, followed by pooling of ideas to conduct group ideation. Design engineers are often encouraged to work in groups to generate concepts and solutions for design problems. However, past research argues that individual ideation results in higher quality design concepts compared to the group ideation methods. The limitations of group ideation such as free riding, production blocking, evaluation apprehension, and goal incongruity are identified …

Bite Detection And Differentiation Using Templates Of Wrist Motion, Soheila Eskandari

All Theses

We introduce a new algorithm of bite detection during an eating activity based on template matching. The algorithm uses a template to model the motion of the wrist over a 6-second window centered on the time when a person takes a bite. We also determine if different types of bites (for example food vs. drink, or using different types of utensils) have different wrist motion templates. This method is implemented on 22,383 bites and 5 different types of templates are built. We then describe a method to recognize different types of bites using the set of templates. The obtained accuracy …

An Exploratory Study On The Effects Of Goal Alignment, Interventions, And Motivational Factors On Innovative Engineering Design Projects, Blake Linnerud

All Theses

Innovation has become an important facet of engineering design, both in industry and the academy. Many senior-level engineering design courses encourage students to develop innovative solutions to open design projects from industry sponsors. Like industry, these academic problems are tackled by teams of students. Student teams that function at the highest level are more likely to reach the innovative solutions for which they are searching. The research presented in this work focuses on two main areas: (1) understanding what motivates engineers when working on innovative design projects and (2) determining the effects of goal alignment interventions on design teams working …

The Effects Of Different Size Gold Nanoparticles On Mechanical Properties Of Vascular Smooth Muscle Cells Under Mechanical Stretching, Tri Kieu

All Theses

The field of nanotechnology research has seen a large growth in the past few decades due to the great potential of novel nano-size material for useful applications such as drug delivery and medical imaging. Also, they are a promising platform for the detection of terrible diseases such as cancer and atherosclerosis. Although these materials hold great promise, there is very limited understanding about the biological effects of these nanoparticles on normal healthy cells, such as vascular smooth muscle cells (VSMCs). The VSMCs are unique cells due to the two distinct phenotype characteristics it can express: a contractile and a synthetic …

Evaporation And Modeling Water Availability In The Savannah River Basin, Ryne Phillips

All Theses

Four methods for estimating lake evaporation are presented and compared. Three are mass transfer methods that incorporated high resolution satellite imagery obtained from the MODIS sensor on the Terra and Aqua satellites. The fourth is the traditional pan method, which used monthly derived pan coefficients and pan evaporation measurements from a Class A evaporation pan located in Clemson, SC.

The four evaporation methods were used to estimate lake evaporation from the five major lakes in the Savannah River Basin for a period of more than one decade. Analysis of the evaporation rates clearly illustrated the uncertainty in daily, monthly, and …

Safety And Operational Characteristics Of Lane Widths On Urban And Rural Roadways A Simulator Study, Meredith Ladue

All Theses

The primary goal for this study was to further evaluate and assess the effect of lane width on the safety and operation of roadways in South Carolina. Due to various site conditions that affect the safety and operations of roadways, highway design engineers often face many challenges when developing appropriate road design standards. To investigate specific site conditions for the South Carolina Department of Transportation (SCDOT) a research study took place. In 2011, Part 1 of this research included field studies conducted by Kevin Baumann and Trey Jordan. Due to the various limitations of the field studies it was evident …

Rapid Riparian Buffer Width And Quality Analysis Using Lidar In South Carolina, Emre Akturk

All Theses

The importance of protecting water quality and aquatic resources are increasing because of harmful human impacts within and around waterways. Establishing or restoring functional riparian areas protect water quality and are a good mechanism to conserve aquatic systems, plants, and wildlife. Laser-based remote sensing technology offers a high resolution approach to both characterize and document changes in riparian buffer zones (RBZs). The objectives of this study were to build a model to calculate riparian buffer width on both sides of a stream using a LiDAR-derived slope variable, to classify riparian buffers and determine their quality, and to evaluate the appropriateness …

Nonlinear Energy Harvesting Under White Noise, Qifan He

All Theses

While purposeful introduction of stiffness nonlinearities into the dynamics of energy harvesters is aimed at enhancing performance under non-stationary and random excitations, most of the conclusions reported in the current literature are based on the steady-state response which assumes a harmonic fixed-frequency excitation. As a result, we still do not have a clear understanding of how the nature of the excitation influences the output power, or what role stiffness nonlinearities play in the transduction of energy harvesters under random excitations. To fill this gap in the current knowledge, this thesis investigates the response of nonlinear mono- and bi-stable energy harvesters …

Design Optimization Of Geometrical Parameters And Material Properties Of Vibrating Bimorph Cantilever Beams With Solid And Honeycomb Substrates For Maximum Energy Harvested, Jasmin Adeshara

All Theses

The objective of this thesis is to maximize the energy harvested from a vibrating bimorph cantilever beam by optimizing the geometrical parameters and the material properties of the piezoelectric beam. A three-dimensional finite element (FEA) model is developed to design a vibrating bimorph cantilever beam for energy harvesting. The reference piezoelectric material used in the design is Lead Zirconate Titanate (PZT-5H) and the substrate sandwiched between the two piezoelectric plates is brass. Three types of models are analyzed and compared in this work by modifying the brass substrate geometry- a solid homogenous substrate, a regular honeycomb substrate and an auxetic …

Experimental Development And Analysis Of A Novel Setup For Insulated Dielectrophoresis, Johnie Hodge

All Theses

Dielectrophoresis has long been studied and utilized for the manipulation of microscale particles in solution. This phenomenon is due to the induced polarization of dielectric particles subjected to an electric field. When the field is also inhomogeneous in terms of the distribution of its strength through space, the polarized particles move and come to rest in certain areas due to the relationship between their and the solvent's relative permittivities. If the electric field is homogenous, such as within a parallel plate capacitor, the particles are polarized according to their permittivity and the field's frequency, but they will not move.
These …

Biological Production Of Succinic Acid Using A Cull Peach Medium, Janani Krishnakumar

All Theses

Biological production of succinic acid from a cull peach based medium was studied using Escherichia coli AFP 184 in a dual-phase batch process including an aerobic growth phase and an anaerobic production phase. Experiments were performed to study the effects of corn steep liquor supplement and exogenous hydrogen supply. About one half of the sucrose in the medium was converted to fermentable sugars glucose and fructose during sterilization. The remaining sucrose was hydrolyzed with invertase. The viscosity of the medium was reduced from 350 cP to 50 cP to allow efficient oxygen transfer by a commercial enzyme product. In the …

Topology Optimization Using A Level Set Penalization With Constrained Topology Features, Luis Fernandez

All Theses

Topology optimization techniques have been applied to structural design problems in order to determine the best material distribution in a given domain. The topology optimization problem is ill-posed because optimal designs tend to have infinite number of holes. In order to regularize this problem, a geometrical constraint, for instance the perimeter of the design (i.e., the measure of the boundary of the solid region, length in 2D problems or the surface area in 3D problems) is usually imposed. In this thesis, a novel methodology to solve the topology optimization problem with a constraint on the number of holes is proposed. …

Thermo-Mechanical Effects Of Thermal Cycled Copper Through Silicon Vias, James Marro

All Theses

The semiconductor industry is currently facing transistor scaling issues due to fabrication thresholds and quantum effects. In this 'More-Than-Moore' era, the industry is developing new ways to increase device performance, such as stacking chips for three-dimensional integrated circuits (3D-IC). The 3D-IC's superior performance over their 2D counterparts can be attributed to the use of vertical interconnects, or through silicon vias (TSV). These interconnects are much shorter, reducing signal delay. However TSVs are susceptible to various thermo-mechanical reliability concerns. Heating during fabrication and use, in conjunction with coefficient of thermal expansion mismatch between the copper TSVs and silicon substrate, create harmful …

Computational Representation Of Linguistic Semantics For Requirement Analysis In Engineering Design, Alex Lash

All Theses

The objective of this research is to use computational linguistics to identify semantic implicit relationships between text-based relationships. Specifically, natural language processing is used to implement linguistic semantics in requirement analyzers. Linguistic semantics is defined as the meaning of words beyond their string form, part of speech, and syntactic function. Many existing design tools use part of speech tagging and sentence parsing as the foundation of their requirement analysis but ultimately use string algorithms to evaluate requirements. These string algorithms cannot capture the implicit knowledge in requirements. This research compares five methods of requirement analysis. A manual analysis provides the …

Improved Photolithography Scheduling In Semiconductor Manufacturing, Sreenath Chalil Madathil

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Photolithography is typically the bottleneck process in semiconductor manufacturing. In this thesis, we present a model for optimizing photolithography job scheduling in the presence of both individual and cluster tools. The combination of individual and cluster tools that process various layers or stages of the semiconductor manufacturing process flow is a special type of flexible flowshop. We seek separately to minimize total weighted completion time and maximize on-time delivery performance. Experimental results suggest that our mathematical- and heuristic-based solution approaches show promise for real world implementation as they can help to improve resource utilization, reduce job completion times, and decrease …

Effectiveness Of Display Trays On Attention And Purchase Of Consumer Products, Erin Snyder

All Theses

Through the collection of qualitative and quantitative data, consumer perception and preference of display trays in the retail environment was examined and evaluated. Purchase decision and eye-tracking data was collected, as well as qualitative survey information, to determine if participants favored packages in a display tray opposed to packages placed directly on store shelving. This preference was measured in terms of time to first fixation, total fixation duration, fixation count as well as final purchasing decision. The experiment analyzed liquid dish soap and canned tomatoes, and was organized as a 2 (products per category) x 1 (display tray per category) …

Flexural Strength Reliability Of Visually Graded Southern Pine Dimensional Lumber, Mengyu Yang

All Theses

The reference design values published in the National Design Specification (NDS) for Wood Construction are derived from full-scale testing of lumber samples performed in the 1980s. This testing program is commonly known as the In-GradeTest Program. Selective annual sample tests of visually graded Southern Pine lumber from 1994 to 2010 revealed an overall decreasing trend in the mechanical properties. Because of this alarming observation, a new round of full-scale In-Grade test of visually graded Southern Pine was initiated in 2010. The new test data indicated significant reductions in certain design values published in the current design code (2005 NDS). …

Improvement Of Onsite Wastewater Treatment By Use Of Electrically Conductive Carbon Cloth, Christopher Weber

All Theses

The purpose of this research is primarily focused on carbon oxidation in domestic septic systems. Small-scale septic waste reactors utilizing electrically conductive carbon cloth were assessed for improving carbon oxidation and therefore the overall efficiency of on-site wastewater treatment systems.
A bioelectrochemical system was developed to enhance carbon oxidation in septic systems using electrically conductive carbon cloth as an anode/cathode bridge to transfer electrons from strictly anoxic septic wastewater to an oxic system outside of the septic reactor. This 'septic snorkel' (so named since the system 'breathes' via the carbon cloth extends into an aerobic zone) was designed to lower …

Removal Of N-Nitrosodimethylamine And Trihalomethane Precursors With Powdered Activated Carbon, Wilson Beita Sandi

All Theses

N-nitrosodimethylamine (NDMA) has been used commercially in several applications, including the production of liquid rocket fuel, and a variety of foods, but gained more relevance when it was discovered as a drinking water disinfection by-product (DBP) in 1989. NDMA is a probable human carcinogen with 10-6 lifetime cancer risk associated with a drinking water concentration of 0.7 ng/L, and is listed as a priority pollutant in the Code of Federal Regulations; no federal maximum contaminant level has been established for drinking water yet. However, the United States Environmental Protection Agency is planning to make a preliminary regulatory determination in 2013 …

Comparison Of Methods To Evaluate Chitosan As An Antimicrobial Against Listeria Spp. Cultures, Scott Hartley

All Theses

The antimicrobial properties of a chitosan-coated vacuum-packaged pouch were tested against Listeria monocytogenes (LM) inoculated on frankfurters. A 1.5% chitosan solution was successfully coated onto a corona-treated poly/nylon based film and then heat-sealed to form a pouch. An initial 5 log CFU/mL population of LM was used to inoculate a frankfurter in the pouch, which was then vacuum-sealed and stored at 4¡ and 13¡ C for a period of 8 weeks, with bacteria enumeration performed on weekly intervals. An uncoated pouch was tested as a control. It was found that the chitosan-coated pouches did not exhibit any antimicrobial properties against …

Evaluation Of Anaerobic Biodegradation Of High Concentrations Of Halogenated Methanes, Priya Rachel Jacob

All Theses

Removal of the chlorinated methanes, carbon tetrachloride (CT), chloroform (CF) and dichloromethane (DCM), and the halogenated methane, trichlorofluoromethane (commonly known as CFC-11 or Freon-11) from contaminated soil and groundwater remains challenging. Releases to the environment resulted from historically poor disposal practices, as well as spills and leaks from underground storage tanks. Among these three compounds, CF is considered the benchmark for evaluating the feasibility of bioremediation, due to its typically high level of toxicity towards most anaerobic prokaryotes. However, inhibitory effects of low concentrations of CFC-11 on anaerobes have been reported as well. Bioremediation is an attractive option for clean-up, …

An Optimization Model For Class Scheduling At A Dance Studio, Chirag Ojha

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Scheduling has been a large area of research for decades. A substantial amount of work has been done to express, classify, and solve scheduling problems. Most of these problems are computationally difficult to solve and require complex algorithms. In this thesis, we develop a mixed-integer linear program for a real world optimization problem at a dance studio. Similar to a university, the students in this studio request a particular class and instructors teach the classes under constrained resources such as a limited number of classrooms. The priorities of instructors as well as dancers are included to further mimic reality. Experimental …