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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, …

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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 …

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The Behavior And Toxicity Of Metal Oxide Nanoparticles In Aqueous Solution, Phenny Mwaanga Dec 2012

The Behavior And Toxicity Of Metal Oxide Nanoparticles In Aqueous Solution, Phenny Mwaanga

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The dissolution and aggregation of metal oxides nanoparticles (NPs) in aqueous solution not only alter the abundance and toxicology of NPs, but also makes the effective assessment and the correct interpretation of effects of NPs on organisms challenging. The extent to which these processes (dissolution and aggregation) occur largely depend on pH, ionic strength, dissolved natural organic matter (NOM) and NPs characteristics. This study investigated the dissolution and aggregation behavior of the four metal oxide NPs (nZnO, nCuO, nFe2O3 and nTiO2) in aqueous solution as influenced by pH, ionic strength and NOM and examined the toxicity of these NPs to …

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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 …

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Fate And Reactivity Of Natural And Manufactured Nanoparticles In Soil/Water Environments, Allison Vandevoort Dec 2012

Fate And Reactivity Of Natural And Manufactured Nanoparticles In Soil/Water Environments, Allison Vandevoort

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Nanoparticles (NPs), < 100 nm in diameter, make up the smallest component of solid material. This small size often causes increased reactivity in soil/water environments, which is true for both natural NPs, such as very fine clay particles, and for manufactured nanoparticles, such as silver nanoparticles (AgNPs). As the importance of these particles is more widely recognized, and as manufactured nanoparticles, especially AgNPs, are increasing in production, it is essential to consider their effect on terrestrial and aquatic environments. The studies presented in this dissertation show that both the physicochemical characteristics of the NPs (e.g., particle size, surface coating, elemental composition), as well as soil-water interfacial chemistry (e.g., ionic strength, ligand concentration, pH), are instrumental in predicting environmental fate and reactivity.
Ligand type and concentration were especially important in NP reactivity and bioavailability. Using the hard/soft acid/base concept, the effect of phosphate ligand (hard base) on Fe/Al (hard acid) oxyhydroxide natural NPs was investigated in Chapters 2 and 3. Adding phosphate to soil NPs and reference nano-minerals (Fe-(oxyhydr)oxides and kaolinite) caused coagulation or dispersion, changing the particle size of the NPs, as well as affecting the amount of phosphate in its bioavailable (i.e., dissolved) form. A review of the literature in Chapters 1 and 3 revealed that changes in the soil conditions, and therefore, soil colloids/NPs (e.g., increasing organic …

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Solvation Energy Of Biomolecular Structures: A Study Of The Effect Of Salt On Biomolecules Through Implicit As Well As Explicit Solvation Methods, Mihir Date Dec 2012

Solvation Energy Of Biomolecular Structures: A Study Of The Effect Of Salt On Biomolecules Through Implicit As Well As Explicit Solvation Methods, Mihir Date

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In the current dissertation, studies related to solvation energy of protein structures using implicit as well explicit solvation methods have been discussed. Special focus is given to explore effect of salt on the fold stability of proteins and enzymes. Salt plays a crucial role in the functioning of all proteins, enzymes and nucleic acids. Change in salt concentration of the medium has large impact on stability and activity of these biological macromolecules. Therefore exploring mechanism of salt effect on them and development of an efficient model to calculate the salt effect has fundamental as well as practical importance in the …

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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 …

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Spectroscopic Signature For Bundling, Edge States And Impurities In 1d And 0d Materials, Kiran Kumar Lingam Dec 2012

Spectroscopic Signature For Bundling, Edge States And Impurities In 1d And 0d Materials, Kiran Kumar Lingam

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Study of nanomaterials has gained interest of researchers from various fields of science and technology due to their unique electronic and vibrational properties as compared to their bulk counterparts. In particular, carbon nanotechnology has evolved rapidly over the past few decades and nowadays, carbon nanotubes are used in various fields such as energy storage, electronics etc. However, the quest for new properties of this material is never ending and the invention of graphene generated enormous interest in the scientific community due to its excellent properties such as strength, high electron mobility, thermal conductivity etc. In this thesis, I aim at …

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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 …

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A Case Study In Collaborative Efforts At Spartanburg Community College, Frederick Cooper Dec 2012

A Case Study In Collaborative Efforts At Spartanburg Community College, Frederick Cooper

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The General Assembly of South Carolina radically changed the structure of secondary education with the enactment of the Education and Economic Development Act (EEDA) of 2005. A provision in the legislation requires post-secondary institutions to develop articulation agreements with secondary institutions in their service area(s). Traditionally, articulation agreements between secondary and post-secondary institutions have been few and far between. The question then becomes how articulation agreements are developed from the post-secondary perspective. Spartanburg Community College is one of the sixteen technical/community colleges in South Carolina. The development of articulation agreements is examined at Spartanburg Community College using the lens of …

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Sample Preparation Techniques For The Improvement Of Analytical Measurements: Capillary-Channeled Polymer Fibers Employed In Protein Solid Phase Extraction Applications And Characterization Of Active Components In Botanical Dietary Supplements, Carolyn Burdette Dec 2012

Sample Preparation Techniques For The Improvement Of Analytical Measurements: Capillary-Channeled Polymer Fibers Employed In Protein Solid Phase Extraction Applications And Characterization Of Active Components In Botanical Dietary Supplements, Carolyn Burdette

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The task of sample preparation encompasses many challenges and demands for analytical techniques. Appropriate preparative steps can be the determining factor between successful measurements and failures. Too little preparation can lead to the inability to detect analytes due to low concentrations, insufficient extraction of analytes, and/or strong matrix effects; exhaustive preparation steps increases analysis times, the potential for analyte losses, and the difficulty to obtain consistent reproducible results. Discussed here are several examples of analytical techniques where sample preparation is critical and can be used to improve existing techniques. Capillary-channeled polymer (C-CP) fibers used for solid phase extraction (SPE) protein …

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Sorption And Enantiomerization Of Current Use Chiral Pesticides, April Hall Dec 2012

Sorption And Enantiomerization Of Current Use Chiral Pesticides, April Hall

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Chiral pesticides are prevalent in the environment today and are known to react selectively with chiral environmental components such as microbes, enzymes, and other naturally occurring chiral materials. In addition, chiral sorption is a process that has been occasionally investigated in the study of homochirality (the exclusive presence of one enantiomer in living organisms), but almost overlooked in environmental science. For chiral sorption to occur, the sorbent and sorbate must be chiral entities. In the environment, there are abundant natural surfaces that are chiral, including clay minerals and organic matter present in soil, sediment and aqueous solution. A knowledge of …

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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 …

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Spider Mediation Of Polychlorinated Biphenyl Transport And Transformation Across Riparian Ecotones, Diana Delach Dec 2012

Spider Mediation Of Polychlorinated Biphenyl Transport And Transformation Across Riparian Ecotones, Diana Delach

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Polychlorinated biphenyls (PCBs) contaminate the sediment of the Twelvemile Creek / Lake Hartwell Superfund Site, and are known to be transported throughout the resident biota via trophic transport. Riparian spiders have recently become of interest because they are terrestrial organisms that have significant PCB exposures derived from aquatic sources. Many riparian spiders primarily consume insects emerging from contaminated aquatic systems, and these spiders can have a body burden as high as 2900 ng/g lipid. These emergent insects carry contaminants out of the river and into the riparian zone where they are captured by spiders, which effectively directs the contamination towards …

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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 …

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Polyhedral Approximations Of Quadratic Semi-Assignment Problems, Disjunctive Programs, And Base-2 Expansions Of Integer Variables, Frank Muldoon Dec 2012

Polyhedral Approximations Of Quadratic Semi-Assignment Problems, Disjunctive Programs, And Base-2 Expansions Of Integer Variables, Frank Muldoon

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This research is concerned with developing improved representations for special families of mixed-discrete programming problems. Such problems can typically be modeled using different mathematical forms, and the representation employed can greatly influence the problem's ability to be solved. Generally speaking, it is desired to obtain mixed 0-1 linear forms whose continuous relaxations provide tight polyhedral outer-approximations to the convex hulls of feasible solutions. This dissertation makes contributions to three distinct problems, providing new forms that improve upon published works.
The first emphasis is on devising solution procedures for the classical quadratic semi-assignment problem(QSAP), which is an NP-hard 0-1 quadratic program. …

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Understanding Nanoparticle-Cell Interaction, Ran Chen Dec 2012

Understanding Nanoparticle-Cell Interaction, Ran Chen

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Nanotechnology has revolutionalized the landscape of modern science and technology, including materials, electronics, therapeutics, bioimaging, sensing, and the environment. Along with these technological advancements, there arises a concern that engineered nanomaterials, owing to their high surface area and high reactivity, may exert adverse effects upon discharge to compromise biological and ecological systems. Research in the past decade has examined the fate of nanomaterials in vitro and in vivo, as well as the interactions between nanoparticles and biological and ecosystems using primarily toxicological and ecotoxicological approaches. However, due to the versatility in the physical and physicochemical properties of nanoparticles, and due …

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Motion Capture Study Of Human Movement Recognition, Nicholas Kinerd Dec 2012

Motion Capture Study Of Human Movement Recognition, Nicholas Kinerd

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In this thesis, we address questions about recognition of human movement through motion
capture. We begin by capturing the martial arts movements of four actors as they each perform
three different techniques. We then conduct a survey to determine if participants in
the survey are able to distinguish the various martial arts techniques and differentiate the
actors that portray said techniques. A secondary consideration of our survey is to determine
if the participants can distinguish the sex of the actors as they perform the martial arts
techniques. Our hypothesis is that people are able to distinguish actors and sex; however, …

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Detecting Copper Residues In Sediments From Aquatic Copper-Based Pesticide Applications, Ben Willis Dec 2012

Detecting Copper Residues In Sediments From Aquatic Copper-Based Pesticide Applications, Ben Willis

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Copper-based algaecides and herbicides are commonly used to mitigate risks of problematic algae and weeds, however there are concerns regarding copper accumulation from treatments. Modeling and laboratory experiments can be used to predict copper accumulation and measurement in sediments, as well as benthic invertebrate responses following treatments. Modeling was used to estimate copper residual concentrations in sediments from algaecide and herbicide treatments. Reported and measured method detection limits (MDLs; minimum concentration of an analyte of interest that can be measured with 99 percent confidence in a specific matrix using an analytical method) were compared to model estimated copper residual concentrations …

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Semantic Similarity Detection In Natural Language Documents, Lianyu Zhao Dec 2012

Semantic Similarity Detection In Natural Language Documents, Lianyu Zhao

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Data leak prevention (DLP) solutions monitor and control data flow. Current techniques find data that matches user defined syntactic patterns. Unfortunately, large classes of DLP relevant data are defined by information semantics, rather than data syntax. Syntax refers to data format, whereas semantics refers to data meaning. The class of social security numbers can be adequately expressed using data syntax, whereas a new industrial process can only be adequately described using information semantics. In this paper, we propose methods for extracting and identifying document semantics using training sets of limited size (tens of documents). The first method is based on …

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An Efficient Image Segmentation Algorithm Using Bidirectional Mahalanobis Distance, Rahul Suresh Dec 2012

An Efficient Image Segmentation Algorithm Using Bidirectional Mahalanobis Distance, Rahul Suresh

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In this thesis, we present an efficient graph-based image-segmentation algorithm that improves upon the drawbacks of the minimum spanning tree based segmentation algorithm, namely leaks that occur due to the criterion used to merge regions, and the sensitivity of the output to the parameter k. To address these problems, we propose the use of bidirectional Mahalanobis distance, along with a Gaussian model for each region, and an intuitive normalized parameter τ that replaces k and works for all images without having to be changed. Furthermore, we propose an approximation to the algorithm that enables it to run efficiently in O(NlogN) …

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Study Of Cell Viability During Laser Direct Writing Of Cell-Alginate Suspension, Hemanth Gudapati Dec 2012

Study Of Cell Viability During Laser Direct Writing Of Cell-Alginate Suspension, Hemanth Gudapati

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Laser-assisted cell printing, developed based on Matrix-assisted pulsed-laser evaporation direct-write (MAPLE DW), a typical LIFT (laser-induced forward transfer) practice, has been emerging as one of the most promising biofabrication techniques. Alginate, particularly sodium alginate, is extensively used as the constituent of bioink in laser-assisted cell printing. However, thus far, studies investigating the effect of alginate gelation on cell viability in laser-assisted cell printing are lacking. The objective of this study is to investigate the effects of gelation, gelation time, sodium alginate concentration, and the effect of operating conditions such as the laser fluence on post-transfer cell viability during laser-assisted cell …

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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 …

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Development Of Feature Recognition Algorithm For Automated Identification Of Duplicate Geometries In Cad Models, Aravind Shanthakumar Dec 2012

Development Of Feature Recognition Algorithm For Automated Identification Of Duplicate Geometries In Cad Models, Aravind Shanthakumar

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This research presents a feature recognition algorithm for the automated identification of duplicate geometries in the CAD assembly. The duplicate geometry is one of the seven indicators of the lazy parts mass reduction method. The lazy parts method is a light weight engineering method that is used for analyzing parts with the mass reduction potential. The duplicate geometry is defined as any geometries lying equal to or within the threshold distance with the user-defined orientation between them and have the percentage similarity that is equal to or greater than the threshold value. The feature recognition system developed in this research …

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Design Automation And Optimization Of Honeycomb Structures For Maximum Sound Transmission Loss, Rohan Galgalikar Dec 2012

Design Automation And Optimization Of Honeycomb Structures For Maximum Sound Transmission Loss, Rohan Galgalikar

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Cellular materials with macro effective properties defined by repeated meso-structures are increasingly replacing conventional homogeneous materials due to their high strength to weight ratio, and controllable effective mechanical properties, such as negative Poisson's ratio and tailored orthotropic elastic properties. Honeycomb structures are a well-known cellular material that has been used extensively in aerospace and other industries where the premium on the weight reduction with high-strength is required. Common applications of honeycomb cellular structures are their use as the core material in sandwich plates and plates between two face sheets. Honeycomb structures are built from repetition of a common hexagonal unit …

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Design And Implementation Of A Genre Hybrid Video Game That Integrates The Curriculum Of An Introductory Programming Course, Cory Buckley Dec 2012

Design And Implementation Of A Genre Hybrid Video Game That Integrates The Curriculum Of An Introductory Programming Course, Cory Buckley

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Video games have a history of being exploited for education. However, all too fre- quently, the resulting educational video game is either transparent in its hijacking of video game media, or the educational content is not intelligently placed within the context of the game. In this paper we analyze existing educational video games and observe popular commercial video game mechanics to form a more player oriented development mindset. Our approach involves mingling game mechanics that are not commonly used together to create a genre hybrid educational video game with a seamlessly integrated introductory programming curriculum. We use a machine architecture …

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Evaluation Of 26al Method As Star Formation Rate Indicator, Manjeet Singh Dec 2012

Evaluation Of 26al Method As Star Formation Rate Indicator, Manjeet Singh

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The aim of this work is to evaluate the '26Al method' used to determine the Galactic Star Formation Rate (SFR) and compare it to other alternative methods. 26Al is a radioactive isotope produced mainly in massive star winds and in the ensuing core collapse supernova explosion. The radioactive 26Al decays with a life time of 106 years by emitting γ- ray photons in 1.808 MeV band. The 26Al method involves using the Galactic 26Al radioactive flux as a tracer. This approach based on the γ- ray line measurements does not suffer from extinction and small number statistics.
To evaluate the …

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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

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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 …

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Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski Dec 2012

Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski

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Some fractured rock formations hold important resources, such as water, hydrocarbons or heat, whereas others are good candidates for waste disposal. Hydromechanical well tests have been developed to improve characterization of formation properties and parameter distributions by measuring displacement along with pressure while stressing a well. The displacement that occurs during a well test depends on the geometry of fractures or other sources of permeability, as well as the distribution of compliance or elastic modulus. Current methods of hydromechanical well testing, measures axial displacements along a wellbore, which may cause ambiguity in interpretations when 3-D components of deformation are present. …

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Study On Corrosion Activity Of Carbon Steel In Concrete Simulated Pore Solution Under Static Tensile And Compressive Stresses, Yujie Zhang Dec 2012

Study On Corrosion Activity Of Carbon Steel In Concrete Simulated Pore Solution Under Static Tensile And Compressive Stresses, Yujie Zhang

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Reinforced concrete is a structure material made up of concrete with relatively lower tensile strength containing reinforcements with higher tensile strength and better ductility, which are embedded into fresh concrete to resist tensile stress in certain regions of concrete. Steel reinforced concrete is most widely used around the world in civil engineering structures, water conservancy and highway construction due to its durability strength and reasonable cost.
However, reinforced concrete structures such as bridges and parking lots slabs inevitably experience variable loads and constant degradation from the aggressive environments, such as marine and deicing salts. Therefore, it is imperative to study …

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