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Induced Elastic Matrix Synthesis Within 3-Dimensional Collagen Constructs, Lavanya Venkataraman Dec 2012

Induced Elastic Matrix Synthesis Within 3-Dimensional Collagen Constructs, Lavanya Venkataraman

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Elastin, a primary component of elastic arteries, maintains structural stability of the cyclically recoiling artery, and critically regulates vascular cell behavior. Accelerated degradation of elastic matrix, such as that seen in vascular pathologies like abdominal aortic aneurysms (AAA), can therefore severely compromise vessel homeostasis. Tissue engineering and in-situ matrix repair strategies evaluated so far are primarily limited in inducing adult vascular cells to replicate the complex elastic matrix assembly process, and restore lost matrix integrity. Previously, our lab established the elastogenic benefits of concurrent delivery of TGF-β1 and HA-oligomers (together termed elastogenic factors, EFs), within 2D cultures of rat aortic …


Photo-Thermal Processing Of Semiconductor Fibers And Thin Films, Nishant Gupta Dec 2012

Photo-Thermal Processing Of Semiconductor Fibers And Thin Films, Nishant Gupta

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Furnace processing and rapid thermal processing (RTP) have been an integral part of several processing steps in semiconductor manufacturing. The performance of RTP techniques can be improved many times by exploiting quantum photo-effects of UV and vacuum ultraviolet (VUV) photons in thermal processing and this technique is known as rapid photo-thermal processing (RPP). As compared to furnace processing and RTP, RPP provides higher diffusion coefficient, lower stress and lower microscopic defects. In this work, a custom designed automated photo assisted processing system was built from individual parts and an incoherent light source. This photo-assisted processing system is used to anneal …


Assessment Of Fidelity To Data And Robustness To Uncertainty To Assure Credible Predictions In The Modeling Of Wind Turbine Blades, Kendra Van Buren Dec 2012

Assessment Of Fidelity To Data And Robustness To Uncertainty To Assure Credible Predictions In The Modeling Of Wind Turbine Blades, Kendra Van Buren

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In the field of wind energy, modeling and simulation techniques provide an efficient and economical alternative to experimentation for studying the behavior of wind turbines. Numerical models however are approximations of reality, thusly making it crucial to evaluate various sources of uncertainties that influence the model predictions. Credibility of a numerical model rests on the model's ability to replicate existing experimental data, widely known as fidelity-to-data. This dissertation advocates that fidelity-to-data, while necessary, is insufficient to claim credibility of a numerical model. Herein, the objective is to develop numerical models that not only provide agreement to experimental data, but also …


Integrated Production And Distribution Problem With Single Perishable Product, Wennian Li Dec 2012

Integrated Production And Distribution Problem With Single Perishable Product, Wennian Li

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This dissertation investigated the extension of the Integrated Production and Distribution Scheduling Problem (IPDSPP) using a variety of perishable products, applying the JIP principle and make-to-order strategy to integrate the production and distribution schedules. A single perishable product with a constant lifetime after production was used in the model discussed here. The objective of the problem was to find the solution that results in minimal system total transportation costs while satisfying customer demand within a fixed time horizon. In the solution, the fleet size, vehicle route and distribution schedule, plant production batch size and schedule were determined simultaneously. This research …


Supply Chain Network Design: Risk-Averse Vs. Risk-Neutral Decision Making, Alireza Madadi Dec 2012

Supply Chain Network Design: Risk-Averse Vs. Risk-Neutral Decision Making, Alireza Madadi

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Recent events, such as the Heparin tragedy, highlight the necessity for designers and planners of supply chain networks to consider the risk of disruptions in spite of their low probability of occurrence. One effective way to hedge against supply chain network disruptions is to have a robustly designed supply chain network. This involves strategic decisions, such as choosing which markets to serve, which suppliers to source from, the location of plants, the types of facilities to use, and tactical decisions, such as production and capacity allocation. In this dissertation, we focus on models for designing supply chain networks that are …


Phase Transformation In Ti-Mo-O, Herbert Boeckels Dec 2012

Phase Transformation In Ti-Mo-O, Herbert Boeckels

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The present dissertation has investigated the effect of oxygen on the ù and á phase stability in metastable Ti-Mo â titanium alloys using thermal analysis, hardness measurements, electron microscopy, and x-ray diffraction.
Single crystal x-ray diffraction has shown that oxygen atoms are located in the tetrahedral interstitial lattice sites in the rapidly cooled bcc Ti crystal structure, interfering directly with the reversible displacive formation of ù, with this transformation involving collapse of the bcc lattice along â. Subsequent thermal exposure of reversible ù, as occurring during slower cooling, heating, and aging, prompts short range diffusion and the formation of chemical …


Develop Novel Frap Techniques For Determining Anisotropic Solute Diffusion In Cartilaginous Tissues, Changcheng Shi Dec 2012

Develop Novel Frap Techniques For Determining Anisotropic Solute Diffusion In Cartilaginous Tissues, Changcheng Shi

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Cartilaginous tissue is a connective tissue composed of specialized cells (e.g., chondrocytes and fibroblasts) that produce a large amount of extracellular matrix (ECM), which is comprised mostly of collagen fibers, abundant ground substance rich in proteoglycan, and elastic fibers. It is characterized by its avascular structures within the tissue, implying that nutrition for normal tissue cells, for maintaining a healthy ECM, is mainly supplied through diffusion from nearby vascularized tissues and synovial fluid. Poor nutritional supply to the cartilaginous tissue is believed to be an important factor leading to tissue degeneration. Moreover, due to the complex collagen fiber structures, the …


Stochastic Tools For Network Security: Anonymity Protocol Analysis And Network Intrusion Detection, Lu Yu Dec 2012

Stochastic Tools For Network Security: Anonymity Protocol Analysis And Network Intrusion Detection, Lu Yu

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With the rapid development of Internet and the sharp increase of network crime, network security has become very important and received a lot of attention.
In this dissertation, we model security issues as stochastic systems. This allows us to find weaknesses in existing security systems and propose new solutions. Exploring the vulnerabilities of existing security tools can prevent cyber-attacks from taking advantages of the system weaknesses. We consider The Onion Router (Tor), which is one of the most popular anonymity systems in use today, and show how to detect a protocol tunnelled through Tor. A hidden Markov model (HMM) is …


Phoneme Weighting And Energy-Based Weighting For Speaker Recognition, Eric Fang Dec 2012

Phoneme Weighting And Energy-Based Weighting For Speaker Recognition, Eric Fang

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This dissertation focuses on determining specific vowel phonemes which work best for speaker identification and speaker verification, and also developing new algorithms to improve speaker identification accuracy. Results from the first part of our research indicate that the vowels /i/, /E/ and /u/ were the ones having the highest recognition scores for both the Gaussian mixture model (GMM) and vector quantization (VQ) methods (at most one classification error). For VQ, /i/, /I/, /e/, /E/ and /@/ had no classification errors. Persons speaking /E/, /o/ and /u/ have been verified well by both GMM and VQ methods in our experiments. For …


Managing Elective And Non-Elective Case Assignments For An Operating Room Suite, Narges Hosseini Dec 2012

Managing Elective And Non-Elective Case Assignments For An Operating Room Suite, Narges Hosseini

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The success of operating room management depends on all levels of decision making, from strategic to tactical and operational decisions. One key decision in systems with block booking is to assign sufficient amount of block time to surgeons and surgery groups. While the typical method of block assignment identifies the share of surgery groups from OR times based on average of past usage, this method does not count for the difference between cost of under and overtime. One of the goals of this research is to develop a decision framework for block assignment. This work is presented in chapter two. …


Network Target Coordination For Design Optimization Of Decomposed Systems, Wenshan Wang Dec 2012

Network Target Coordination For Design Optimization Of Decomposed Systems, Wenshan Wang

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A complex engineered system is often decomposed into a number of different subsystems that interact on one another and together produce results not obtainable by the subsystems alone. Effective coordination of the interdependencies shared among these subsystems is critical to fulfill the stakeholder expectations and technical requirements of the original system. The past research has shown that various coordination methods obtain different solution accuracies and exhibit different computational efficiencies when solving a decomposed system. Addressing these coordination decisions may lead to improved complex system design. This dissertation studies coordination methods through two types of decomposition structures, hierarchical, and nonhierarchical.
For …


Flow Behavior Modeling And Process Control Of Electrically-Assisted Forming (Eaf) For Sheet Metals In Uniaxial Tension, Joshua Jones Dec 2012

Flow Behavior Modeling And Process Control Of Electrically-Assisted Forming (Eaf) For Sheet Metals In Uniaxial Tension, Joshua Jones

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This work studies the influence of an applied electrical current on magnesium sheet metal and introduces models which are successful in predicting the deformation behavior (i.e. material flow stress, local material strain, and thermal response). Also, this work examined the theory of electroplasticity by studying prior proposed theories and by quantifying the prior theories potential for improved dislocation mobility. From this analysis, a single dominant mechanism is determined and the theory of electroplasticity is explained using this single mechanism. The theory discussed in this work is supported by experimental testing and microstructure analysis.
In addition to studying the exact electroplastic …


Application Of Carbon Dioxide Towards The Development Of Smart Materials, Green Reaction Schemes And Metallic Nanoparticle Synthesis, Fiaz Mohammed Dec 2012

Application Of Carbon Dioxide Towards The Development Of Smart Materials, Green Reaction Schemes And Metallic Nanoparticle Synthesis, Fiaz Mohammed

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Global carbon dioxide (CO2) emissions have steadily risen over the last 50 years, with 34 billion tons of CO2 released in 2009 alone. Its potential as a greenhouse gas has negatively affected of our lives and environment by the resulting ocean acidification and climate change. To mitigate atmospheric CO2, various strategies have been implemented for CO2 separation, capture, storage and use as a chemical feedstock. The use of CO2 in various chemical industries is attractive as its non-flammable, non-toxic, and relatively inert properties have made it an inherently safer alternative to traditional organic …


On-Line Transient Stability Studies Incorporating Wind Power, Zhenhua Wang Dec 2012

On-Line Transient Stability Studies Incorporating Wind Power, Zhenhua Wang

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Transient stability is a major concern in power system security and reliability because it is the most common type of instability and its impacts can cause greatest economic losses. For enhancing the energy security, it requires the power system operation to be evaluated during both the planning and the operation stage. Many online/offline transient stability assessment techniques have already been developed for this purpose. However, due to the increase in energy demand, the modern power system has grown to a very sophisticated and large system for which extent transient stability assessment methods may not be able to handle. In addition, …


Examination Of The Effectiveness Of Bioretention Cells And Porous Paving Practices In Aiken, Sc, Casey Johnson Dec 2012

Examination Of The Effectiveness Of Bioretention Cells And Porous Paving Practices In Aiken, Sc, Casey Johnson

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This work seeks to quantify the impact and effectiveness of green infrastructure practices, specifically bioretention cells and porous asphalts, for the reduction of peak flow and volume of stormwater that discharges into the headwaters of the Sand River watershed in Aiken, SC. Stormwater runoff flows and volumes were monitored in the upper Sand River watershed that includes the urban Aiken area, along with two nested subwatersheds, prior to, during, and after the construction of the bioretention cells and porous asphalt sites. Flow data from these monitoring stations were analyzed and the data suggested that there was no significant reduction in …


Product Display Versus Graphical Representation On Packaging, Joshua Galvarino Dec 2012

Product Display Versus Graphical Representation On Packaging, Joshua Galvarino

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ABSTRACT
Previous research conducted (Hurley, et al., 2012) concerning physical and graphical product visibility from the primary display panel (PDP) is limited to one product category. This research expands previous peer-reviewed research, which indicates that there is a significant difference between consumer preferences of graphical display vs. physical product display on packaging.
The shelf presence of packages showing actual product visibility versus packages showing only a graphical representation of the product was evaluated. Both shopping results and quantitative data using eye-tracking technology were collected and cross-referenced with a qualitative, post-experiment survey.
Specifically, variables of packaging within pasta, snacks, prepared frozen …


Analysis Of Energy Savings Through The Use Of Displacement Ventilation In Domestic Buildings, Patrick Daffin Dec 2012

Analysis Of Energy Savings Through The Use Of Displacement Ventilation In Domestic Buildings, Patrick Daffin

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This study investigates the conditions under which it might be possible to implement a displacement ventilation system in a residential building. An experimental study of the impact on a mechanical air conditioning system of the vertical location of the inlet and outlet vents was performed. The four ventilation configurations of low inlet high outlet, low inlet low outlet, high inlet high outlet, and high inlet low outlet were compared. These four configurations were compared under 13 different heat load scenarios in a full scale instrumented model room. It was found that, for higher heat loads, the low inlet high outlet …


In Situ Ground Freezing And Sampling Of A Pleistocene Sand Deposit In The South Carolina Coastal Plain, Michael Esposito Iii Dec 2012

In Situ Ground Freezing And Sampling Of A Pleistocene Sand Deposit In The South Carolina Coastal Plain, Michael Esposito Iii

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The procedures used to freeze and sample a Pleistocene sand deposit at the Coastal Research and Education Center near Charleston, South Carolina to preserve and study the effects of diagenesis are presented in this thesis. An initial feasibility study was conducted to target a layer of clean sand at the CREC site with little to no frost heave potential. To freeze the sand deposit, a ground freezing system with a central freezing pipe was installed to target a column of sand 1-m in radius and 2.3-m long. Liquid nitrogen was continuously supplied to the large steel freezing pipe, which was …


Bioswellable Amphiphilic Copolymers, David Ingram Dec 2012

Bioswellable Amphiphilic Copolymers, David Ingram

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The suture is one of the most commonly used medical devices, consisting of a fiber, a surgical needle and the packaging in which it is stored. The fiber itself remains after implantation for a defined time and is responsible for the approximation of the wound during the healing process. The needle merely serves to aid in insertion, and preferably has a diameter larger than the diameter of the fiber .
The 1970's marked the birth of a new family of fibrous materials for the approximation of wounds: synthetic absorbable sutures. This family has the ability to provide wound support during …


Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan Dec 2012

Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan

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Growing fresh water needs have led to an interest in water desalination using reverse osmosis (RO) membranes. Energy consumption has a large share in the expenses incurred to drive a reverse osmosis desalination system. With depleting fossil fuel reserves, tapping renewable sources of energy is a promising alternative to meet the energy requirements. Wind power coupled to an RO desalination system is a potential means of delivering clean water using sustainable energy. This work investigates modeling of a conceptual wind-energy-driven RO desalination system that is made possible because of an air-pressure energy storage mechanism. Bench-scale experiments were performed on an …


Estimating Water Flux And Storage Using Displacement Measurements In Saprolite At Depth, Clay Freeman Dec 2012

Estimating Water Flux And Storage Using Displacement Measurements In Saprolite At Depth, Clay Freeman

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Water storage in the soil is important for many hydrologic problems, but measuring how the storage changes at an appropriate scale remains a challenge. The objective of this thesis is to evaluate the feasibility of estimating change in water content in soil by measuring vertical displacement in underlying soils. This approach is appealing because the averaging volume of the displacement scales with the depth at which the measurements are taken. This should result in measurements of changes in soil moisture that are averaged over regions 10s to 100s of meters across, a measurement scale that is much larger than that …


Dynamic And Static Effects In Wetting Of Capillaries And Fibers, Taras Andrukh Dec 2012

Dynamic And Static Effects In Wetting Of Capillaries And Fibers, Taras Andrukh

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This research is centered on the analysis of static and dynamic effects of wetting of single capillaries and fibers. We discuss specifics of the capillary rise and drop-on-fiber techniques and develop new methods of characterization of surface energy of single fibers when its contact angle varies between zero and ninety degrees. The contact angles were evaluated and compared for different substrates. We study the dynamics of the meniscus formation inside and outside of capillaries and fibers. We develop a mathematical model of liquid uptake by capillaries and analyze the factors affecting liquid uptake. The derived fundamental equation describes the dynamics …


A Process Analysis Of Engineering Problem Solving And Assessment Of Problem Solving Skills, Sarah Grigg Dec 2012

A Process Analysis Of Engineering Problem Solving And Assessment Of Problem Solving Skills, Sarah Grigg

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In the engineering profession, one of the most critical skills to possess is accurate and efficient problem solving. Thus, engineering educators should strive to help students develop skills needed to become competent problem solvers. In order to measure the development of skills, it is necessary to assess student performance, identify any deficiencies present in problem solving attempts, and identify trends in performance over time. Through iterative assessment using standard assessment metrics, researchers/instructors are able to track trends in problem solving performance across time, which can serve as a gauge of students' learning gains.
This research endeavor studies the problem solving …


Updated Force Model For Milling Nickel-Based Superalloys, Andrew Henderson Dec 2012

Updated Force Model For Milling Nickel-Based Superalloys, Andrew Henderson

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Nickel-based superalloys are commonly used in applications which require high strength and resistance to creep and oxidation in extreme conditions. All nickel-based superalloys are considered difficult to machine; however, cast gamma-prime-strengthened nickel-based superalloys are more difficult to machine than common nickel-based superalloys. Machining comprises a significant portion of manufacturing processes and with advancements in technology and material properties, the methods and models used must be adapted in order to keep pace.
In this research, correlations are made, using fundamental principles, between measurements made with on-machine touch probes and the cutting tool's wear state, those correlations are used in an adaptive …


Improving Accuracy In Ultra-Wideband Indoor Position Tracking Through Noise Modeling And Augmentation, Salil Banerjee Dec 2012

Improving Accuracy In Ultra-Wideband Indoor Position Tracking Through Noise Modeling And Augmentation, Salil Banerjee

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The goal of this research is to improve the precision in tracking of an ultra-wideband (UWB) based Local Positioning System (LPS). This work is motivated by the approach taken to improve the accuracies in the Global Positioning System (GPS), through noise modeling and augmentation. Since UWB indoor position tracking is accomplished using methods similar to that of the GPS, the same two general approaches can be used to improve accuracy.
Trilateration calculations are affected by errors in distance measurements from the set of fixed points to the object of interest. When these errors are systemic, each distinct set of fixed …


Double Paddle Oscillators For The Mechanical Spectroscopy Of Ion-Solid Interactions, Jason Puls Dec 2012

Double Paddle Oscillators For The Mechanical Spectroscopy Of Ion-Solid Interactions, Jason Puls

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We demonstrated using a double paddle oscillator to measure subsurface defect formation at room temperatures caused by ion implantation. This sensor has a low amount of noise based because of its high quality factors in certain modes. The double paddle oscillator was bombarded with Ar ions under ultra-high vacuum conditions while it was oscillating. The resultant resonant frequency changes were discussed as a method to determine defect formation inside the bulk substrate.


Connecting Architecture, Fitness, Optimizations And Performance Using An Anisotropic Diffusion Filter, Sumedh Naik Dec 2012

Connecting Architecture, Fitness, Optimizations And Performance Using An Anisotropic Diffusion Filter, Sumedh Naik

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Over the past decade, computing architectures have continued to exploit multiple levels of parallelism in applications. This increased interest in parallel computing has not only fueled the growth of multi-core processors but has also lead to an emergence of several non-traditional computing architectures like General Purpose Graphical Processing Units (GP-GPUs), Cell Processors, and Field Programmable Gate Arrays (FPGAs). Of these non-traditional computing architectures, GP-GPUs have gained widespread popularity due to their massively parallel computational abilities and relative ease of programmability.
Several software development ecosystems have emerged to harness the power of these parallel architectures. Although several threading libraries like POSIX …


Alternative Energy Sources - Integration Of Power Generation Systems Into A Microgrid At Clemson University And An Atmospheric Thermodynamic Driven Mechanical Clock, Shreyas Patel Dec 2012

Alternative Energy Sources - Integration Of Power Generation Systems Into A Microgrid At Clemson University And An Atmospheric Thermodynamic Driven Mechanical Clock, Shreyas Patel

All Theses

Non-renewable energy sources such as coal, crude oil, and natural gas are being consumed at a brisk pace which is promoting a worldwide energy crisis. The burning of fossil fuels produces greenhouse gases such as carbon dioxide and nitrous oxides as well as soot which contribute to atmospheric pollution. Although fossil fuels will continue to be available for many decades, the amount of petroleum remaining in the earth and its associated cost remains an open issue. The utilization of green energy such as solar and wind offer renewable and pollution free sources. A worldwide shift is slowly underway towards the …


The Effects Of Low Dose Ionizing Radiation Exposure On The Metabolic And Mechanical Properties Of Articular Cartilage, Carl Lindburg Dec 2012

The Effects Of Low Dose Ionizing Radiation Exposure On The Metabolic And Mechanical Properties Of Articular Cartilage, Carl Lindburg

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Radiation therapy is necessary treatment for many cancer patients due to its non-surgical, yet aggressive and efficacious properties. In fact, over 50% of patients with cancer will undergo some form of radiotherapy during the course of their treatment. While the biological response to ionizing radiation has been examined over the years and many adverse effects have been identified, the effects of radiation on mature cartilage and musculoskeletal tissues are not well understood. Bone, once thought to be a tissue relatively resistant to radiation, has recently been shown to have osteoporosis-like bone atrophy after exposure to low doses (2 Gy) of …


Towards Trustworthy, Efficient And Scalable Distributed Wireless Systems, Ze Li Dec 2012

Towards Trustworthy, Efficient And Scalable Distributed Wireless Systems, Ze Li

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Advances in wireless technologies have enabled distributed mobile devices to connect with each other to form distributed wireless systems. Due to the absence of infrastructure, distributed wireless systems require node cooperation in multi-hop routing. However, the openness and decentralized nature of distributed wireless systems where each node labors under a resource constraint introduces three challenges: (1) cooperation incentives that effectively encourage nodes to offer services and thwart the intentions of selfish and malicious nodes, (2) cooperation incentives that are efficient to deploy, use and maintain, and (3) routing to efficiently deliver messages with less overhead and lower delay. While most …