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Vortex Model Of Open Channel Flows With Gravel Beds, Brian James Belcher

University of Kentucky Doctoral Dissertations

Turbulent structures are known to be important physical processes in gravel-bed rivers. A number of limitations exist that prohibit the advancement and prediction of turbulence structures for optimization of civil infrastructure, biological habitats and sediment transport in gravel-bed rivers. This includes measurement limitations that prohibit characterization of size and strength of turbulent structures in the riverine environment for different case studies as well as traditional numerical modeling limitations that prohibit modeling and prediction of turbulent structure for heterogeneous beds under high Reynolds number flows using the Navier-Stokes equations. While these limitations exist, researchers have developed various theories for the structure …

Investigation Of Surface Fine Grained Laminae, Streambed, And Streambank Processes Using A Watershed Scale Hydrologic And Sediment Transport Model, Joseph Paul Russo

University of Kentucky Doctoral Dissertations

Sediment transport at the watershed scale in the Bluegrass Region of Kentucky is dominated by surface fine grained laminae, streambed, and streambank erosion; high instream sediment storage; and surface erosion processes. All these processes can be impacted by agricultural, urban, and suburban land-uses as well as hydrologic forcing. Understanding sediment transport processes at the watershed scale is a need for budgeting and controlling sediment pollution, and watershed modeling enables investigation of the cumulative effect of sediment processes and the parameters controlling these processes upon the entire sediment budget for a watershed. Sediment transport is being modeled by coupling the hydrologic …

Protein Responsive Synthetic Materials For Biomedical Applications, Youyou Zheng

Doctoral Dissertations

"The production of synthetic materials with molecular recognition abilities towards biomacromolecules has been widely researched because of its potential applications in separations, sensing, therapeutics, etc. While molecular imprinting has become a commercially viable method for the production of synthetic materials with molecular recognition abilities towards small molecules, little success has been recorded towards protein targets. Proteins are difficult to imprint as they present a number of epitopes for imprinting, are difficult to remove from the completed material, and are incompatible with the densely crosslinked structures required. As a result, a novel surface molecular imprinting technique was developed to synthesize polymeric …

Rational Construction By Molecular Dynamics Modeling And Simulations Of Porous Adsorbent Media For Bioseparation, Enrico Riccardi

Doctoral Dissertations

"Ion-exchange chromatography employing porous adsorbent particles or monoliths in which charged ligands are immobilized onto polymeric extender molecules grafted on the pore surfaces of a base matrix has become a very important method for bioseparations. In this dissertation, a novel fundamental and systematic methodology has been developed that uses the molecular dynamics (MD) modeling and simulation approach to rationally design, construct, and characterize polymeric porous adsorbent media and study the transport and adsorption of a charged biomolecule (desmopressin) in a representative adsorbent medium. The MD results have also been utilized in a macroscopic model to study the large-scale dynamic behavior …

Decentralized Adaptive Neural Network Control Of Interconnected Nonlinear Dynamical Systems With Application To Power System, Shahab Mehraeen

Doctoral Dissertations

"Traditional nonlinear techniques cannot be directly applicable to control large scale interconnected nonlinear dynamic systems due their sheer size and unavailability of system dynamics. Therefore, in this dissertation, the decentralized adaptive neural network (NN) control of a class of nonlinear interconnected dynamic systems is introduced and its application to power systems is presented in the form of six papers. In the first paper, a new nonlinear dynamical representation in the form of a large scale interconnected system for a power network free of algebraic equations with multiple UPFCs as nonlinear controllers is presented. Then, oscillation damping for UPFCs using adaptive …

Membrane Properties Of Intact Rock Cores Of Burlington Limestone, Jefferson Dolomite, Darrington Phyllite, And Low Permeability Concrete, Megan Hart

Doctoral Dissertations

"A number of laboratory studies have shown that clays exhibit membrane properties. However, little research has been performed on lithologies outside of pure clays. Recently, research focusing on mixed sand and clay membrane properties for engineering applications was performed. Still, literature only suggests the possibilities of membrane properties, osmotic or reverse-osmotic, associated with other naturally occurring 'tight' rock types. Therefore, the objectives of this research was to perform a series of hyperfiltration experiments using actual rock discs of Quarry Ridge Jefferson Dolomite, Darrington Phyllite, Lower Burlington Limestone, and low permeability concrete to determine if tight lithologies can function as membranes"--Abstract, …

Freeze Casting Of Bioactive Glass And Ceramic Scaffolds For Bone Tissue Engineering, Qiang Fu

Doctoral Dissertations

"The main objectives of this dissertation were to explore the production of bioactive ceramic and glass scaffolds with oriented pore architectures by unidirectional freezing of suspensions, and to characterize the mechanical and biological performance of the scaffolds. Freezing of aqueous suspensions of hydroxyapatite (HA) or bioactive 13-93 glass particles resulted in the formation of scaffolds with a lamellar-type microstructure (pore width = 5-30 µm). The addition of polar organic solvents (such as 60 wt% dioxane) to the aqueous suspensions markedly changed the morphology and size of the oriented pores, giving scaffolds with a columnar-type microstructure and larger pre width (90-110 …

Helical Force Flow: A New Engineering Mechanics Model For Biological Materials, Jeffery S. Thomas

Doctoral Dissertations

"The author has long speculated that the prevalence of helical structures in botany and zoology hints to an optimized pathway for force and/or energy transfer. His goal has been to realize an alternative approach to the standard stress analysis used in engineering in order to more efficiently and accurately deal with biological materials. Improved tools for these natural materials should in turn aid the design and analysis of engineered materials. Following the role of a navigator in leaf C. Levesque's book "Breakthrough Creativity", the author typically searches for ideas in a variety of places, including physics, materials science, biomimetics, dimensional …

Application Of Sensor Fusion To Human Locomotor System, John Kweku Avor

Open Access Theses & Dissertations

This research study proposes a multi-sensor data fusion technique to determine the complex interactions between the sensory, muscular and mechanical components of the human locomotor systems (neuromechanics). The object in this work is to demonstrate the viability in using inertial sensors for accurate gait phase determination and to present the acceleration effect specific body segment contributes in order to establish a functional gait. The current method used in determining gait phases consist of combining ground reaction force and angular data, this method is time consuming and cannot be totally reliable. We found out that gait phases can be determined distinctively …

Sustainable Development Extension Plan (Sudex): Community Mobilization Through Proactive Participation And Synergistic Alliance To Alliviate Poverty And Achieve Sustainable Self Sufficiency, Stephen Forbes

Open Access Theses & Dissertations

This Dissertation describes a sustainable development extension plan (Sudex Plan) to help communities in developing countries achieve Goal 1 of the United Nation's Millennium Development Goals (MDG). Goal 1 focuses on reducing poverty and hunger by 50% by the year 2015, but all the MDG are interrelated and one can not be achieved without considering the others, and to attain any is an empty accomplishment without ways to ensure that they can be sustained and continuously improved with the means to pass on the information, knowledge and lessons learned from community to community, generation to generation. The Sudex Plan is …

Directional Analysis And Filtering For Dust Storm Detection In Noaa-Avhrr Imagery, Swapna Janugani

Open Access Theses & Dissertations

In this research, we propose spatio-spectral processing techniques for the detection of dust storms in 5-band NOAA-AVHRR imagery. The research is mainly focused on locating the dust sources and automatically finding the transport direction of the dust storm. Previous methods that use simple band math analysis have produced promising results but have some drawback in producing consistent results when low SNR images are used. Moreover, in seeking to automate the dust storm detection, the presence of clouds in the vicinity of the dust storm creates a challenge in being able to distinguish these two types of image texture. Our research …

Detection Of Gas/Odor Based On Quartz Crystal Microbalance Sensors And Fuzzy Similarity Measure, Yi-Chen Lo

Open Access Theses & Dissertations

In this research, an array of six Quartz Crystal Microbalance sensors (QCM) using fuzzy similar measurement is proposed to recognize different gases and the percentage of those gases in a mixed gas. The experiment suggests three different gases, oxygen, helium, and argon as test gases and the nitrogen as the reference gas. Six QCMs in this array are coated respectively with six different specific polymers that are selected based on Linear Solvation Energy Relationship (LSER) method, in order to absorb gas molecules so as to recognize responses of resonant frequency changes from QCMs. Testing with different gases results in different …

Computational Modeling Studies Of The Structures And Properties Of Organotin(Iv) And Stannyl-Thioether Systems With Comparisons To X-Ray Crystallography, Michelle R. Stem Joseph

Open Access Theses & Dissertations

Controlling the toxic effects of organotin(IV) compounds involves engineering the structure of the molecules to optimize their properties. Molecular engineering, coupled with improved capabilities to generate reliable computational optimization models (COMs), will enable researchers to have greater success at harnessing the highly specific cytotoxicity of organotins. For example, as the thio_n ligand phenyl groups were replaced with Cl atoms, the S-Sn intramolecularity was strengthened, the bond distance decreased, and the stannyl tetrahedral structure was deformed from its triphenyl conformation. With each substitution, conformation deformations lowered the damaging bioactivity levels of thio_n. Bonding various ligands to organotin(IV) compounds …

Characterization And Cytotoxic Assessment Of Ballistic Aerosolized Particulates For Tungsten Alloy Penetrators Interacting With Steel Targets, Brenda Ivette Machado

Open Access Theses & Dissertations

The aerosolized particulates produced during an impact of depleted uranium munitions can potentially contaminate extensive areas around the impact sites and cause a wide spectrum of civilian and military damage. Thus materials such as WHA have been prompted for consideration. The present research is concerned with the regular collection of aerosol particulates associated with ballistic WHA rod penetration into rolled homogeneous steel (RHA) or other related steel armor as armor plate sequences. Particulate size characterization via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) along with chemical compositions via energy dispersive spectroscopy (EDS) were the focus of this research. …

An Integrated Software Package For Model-Based Neuro-Fuzzy Classification Of Small Airway Dysfunction, Nazila Hafezi

Open Access Theses & Dissertations

Respiratory disorders can be difficult to differentiate, as their symptoms are sometimes similar to one another. Concerning asthma which is the major interest in this research, early detection of small airway impairment could greatly help with timely diagnosis. In this research, an integrated software package (ISP) has been developed to help clinicians in classification of asthma severities using Impulse Oscillation data.

The ISP has been developed based on object-oriented methodology. In this package, IOS "diagnostic" parameters such as AX and frequency-dependence of resistance as well as parameter estimates of extended RIC (eRIC) and augmented RIC (aRIC) models (simplified cases of …

Effect Of Air Addition On Plasma-Based Reforming Of Methane And Propane, Atul Vitthalrao Ambhore

Open Access Theses & Dissertations

No abstract provided.

Silica Removal From Brine By Using Ion Exchange, Carlos R. Acevedo

Open Access Theses & Dissertations

Local governments have been forced to look for additional water sources to satisfy the ever increasing demand for fresh water. Very often, the new water sources such as the underground water in continental territories have high salt content. Currently, reverse osmosis technology (RO) is one of the most common processes for water desalination. However, this process is limited by high silica and salt concentrations in water. At high concentrations silica clogs the membranes used in the RO process, reducing their life and increasing operational costs. In this study, quaternary ammonium resins and sulfonic acid resins were used to remove silica …

Multi-Objective Network Reliability Optimization Using Evolutionary Algorithms, Franciso Oswaldo Aguirre

Open Access Theses & Dissertations

This work presents a new multiple objective evolutionary algorithm to solve three well known network reliability allocation problems considering different conflicting objectives to be optimized simultaneously. The new algorithm is applied in the design of a telecommunication network that is formed for several stations or nodes interconnected by telecommunication links or paths. The problem presented in this work involves finding which links to activate in order to obtain connectivity in the nodes. The number of nodes that need to be connected depends of the case that is being evaluated. The three network reliability problems considered are: all-terminal, k-terminal, and two-terminal. …

Microstructure And Electrical Performance Of Sputter-Deposited Hafnium Oxide (Hfo2) Thin Films, Brandon Adrian Aguirre

Open Access Theses & Dissertations

Hafnium oxide (HfO2) based dielectrics have been currently considered as the possible replacements for the traditional gate-oxide (SiO2) of the complementary metal-oxide semiconductor (CMOS) devices. The high dielectric constant, wide band gap, and thermal stability in contact with Si make HfO2 a potential material for application in CMOS devices. The performance of HfO2 as a gate oxide material, however, depends on its quality and interface structure with Si. In this work, HfO2 thin films have been deposited by rf sputtering onto Si(100) substrates under varying growth temperatures (Ts). The objective of the work is to understand the growth and microstructure …

Failure Analysis And Materials Characterization Of Hip Implants, Amanda Marie Bastidos

Open Access Theses & Dissertations

This research focused on the microstructural characterization and failure analysis of hip implant components. The main hip components analyzed were the femoral heads and the ultra-high molecular weight polyethylene (UHMWPE) liners. Previous research has shown that hip implants tend to fail by the PE liners due to adhesive and abrasive wear, delamination, and third body particles (metals, ceramics, and PE). The methods and procedures for analyzing the said failures consisted of non-destructive and destructive evaluations. Non-destructive evaluations included of techniques such as visual characterization and dye penetrant inspection (DPI)-which displayed macroscopic surface details and presented initial clues as to the …

Art In A New Light: Design And Assessment Of Illuminants To Reduce Photochemical Degradation Of Works Of Art, Monica Fabiola Delgado

Open Access Theses & Dissertations

The purpose of this research is to design the best lighting that will minimize long term photochemical degradation of Old Master Drawings and/or other works of art, while maintaining the patron's appreciation of the object's color and detail. The present approach is a technological refinement to the basic underlying earlier work on fluorescent lighting by W. A. Thornton, W.A. at General Electric1. Thin-film dielectric, multi-coating technology is used to create filters that eliminate ultraviolet light, near infrared light and significant unnecessary parts from the visible spectrum, thus maximizing the reduction in photochemical degradation, while maintaining optimal color rendering. Three interference …

Electric Power Distribution Optimization Using Evolutionary Algorithms, Sowmya Parimi

Open Access Theses & Dissertations

In the present research, a new evolutionary algorithm is developed to solve the component allocation problem in electricity distribution systems. The problem addresses the upgrade/design of an electricity distribution system with the objective of minimizing expected system downtime subject to cost and repair time constraints. The algorithm is tested on the Dual Element Spot Network (DESN) configuration which is one of the most commonly used configurations by the power industry. This algorithm is demonstrated with two examples.

Retrofitting A Stereolithography System Within A Laminar Flow Hood, Mahesh Pandurang Tonde

Open Access Theses & Dissertations

This research focused on retrofitting the stereolithography (SL), a rapid prototyping technology, inside a laminar flow hood to provide an aseptic, particulate-free environment for scaffold fabrication. Two of the important objectives of this project were to retrofit the commercial SLA 250/30 inside a laminar flow hood to demonstrate that the manufacturability of the Bio-SL system was comparable to original SLA 250 system and to conduct the sterility test on fabricated scaffolds to show that the laminar flow hood was able to provide an aseptic, particulate-free environment for the fabrication.

Vision-Based Virtual Mouse System, Tom Wanjala Watiti

Open Access Theses & Dissertations

This thesis describes a virtual mouse system that utilizes machine vision technology to enable a user to navigate through software window screens on a standard personal computer, access and control software, and/or peripheral devices attached to the personal computer. Utilizing the virtual mouse, the user can execute the standard control functions of the system mouse required to perform software application selection functions and navigation tasks without physical interface with the controlled computer. The machine vision algorithm utilizes a set of four simulated photoelectric sensors, with Gaussian filter sensitivities, to compute and track the mouse location. By utilizing Gaussian filters, instead …

Multiple Objective Optimization Of Performance Based Logistics, Delia Villanueva

Open Access Theses & Dissertations

This thesis presents a new Performance Based Logistics optimization model. Performance Based Logistics (PBL) is becoming increasingly important for manufacturers in mission critical environments that need to provide ultimate product availability at the lowest cost and with the highest level of customer satisfaction. The U.S. Department of Defense has mandated that Performance Based Logistics programs be adopted by its major weapon systems and equipment suppliers, is one of the newest support strategies to improve the weapon system readiness. This work presents a new multiple objective evolutionary approach that simultaneously optimizes objectives such as Reliability, Maintainability and Total Cost for Ownership. …

Autonomous Vehicle Navigation: A Comparative Study Of Classical Logic And Neural Network Technique, Javier Alejandro Flores

Open Access Theses & Dissertations

Today is an era in which humans need the help of automated machines to facilitate their hectic lives. Over the past few decades, robotics has been one of the most researched areas in the world. One area of this research is obstacle avoidance for autonomous vehicles. In order to avoid an obstacle, the system may include two important characteristics: obstacle detection and avoidance control. In this Thesis a classical logic system and artificial neural network approach is presented. With the help of an Integrated Development Environment, a virtual robot was able to negotiate a maze and avoid obstacles according to …

Nondestructive Testing For Finding Out The Displacement Of Crack In Silicon Nitride, Sriharsha Kurra

Open Access Theses & Dissertations

Nondestructive testing (NDT) has become an increasingly vital factor in the effective conduct of research, development, design and manufacturing. Only with the appropriate use of nondestructive testing techniques, the benefits of advanced materials science can be fully realized. NDT has a wide range of industrial applications and various methods and techniques are employed to perform the nondestructive testing. The current work aims to demonstrate the nondestructive testing technique applied to determine the damage in silicon nitride. Ceramics are brittle materials and non destructive evaluation methods are required to assess the quality and reliability of them. A nondestructive evaluation technique has …

Exploring Poly(Ethylene Glycol) As A Suitable Material For Peripheral Nerve Regeneration Scaffolds Manufactured By Stereolithography, Nubia Zuverza

Open Access Theses & Dissertations

One of the challenges in tissue engineering is to have spatial and temporal control over the biological elements within a scaffold used to guide regeneration for example of transected nerves. Some of the physical and chemical characteristics to regulate include incorporation of bioactive domains and release of chemical signals. This study presents the use of stereolithography (SL) to incorporate localized domains for cell adhesion in addition to include releasable nerve growth factor (NGF) in the process of building poly(ethylene glycol)diacrylate (PEGda) hydrogel scaffolds. Besides providing sites for cell attachment, an ideal nerve guidance conduit (NGC) should be able to release …

Carbon Dioxide Capture From Flue Gases, Mohamed Rashid Al Rashid

Theses

Global warming and climate change are believed to be caused by the greenhouse effect. CO₂ has been regarded as the main contributor to global climate change which directly results in serious environmental problems. Half of the anthropogenic CO₂ emission sources are emitted from the combustion of fossil fuels in industries and power plants worldwide. The absorption behavior of Carbon dioxide from flue gases can be studied using conventional absorber and polymeric hollow fiber membrane contractors. An industrial absorber data was compared with simulated data using hollow fiber membrane contractor using the gPROMs software package. In this analysis, with …

Demonstration Of Microcantilever Array With Simultaneous Readout Using An In-Plane Photonic Transduction Method, Seunghyun Kim, Gregory P. Nordin, Ryan Anderson, Weisheng Hu, Yusheng Qian, Jiguo Song, Jong Wook Noh

Faculty Publications

We demonstrate a microcantilever array with an in-plane photonic transduction method for simultaneous readout of each microcantilever. The array is fabricated on a silicon-on-insulator substrate. Rib waveguides in conjunction with a compact waveguide splitter network comprised of trench-based splitters and trench-based bends route light from a single optical input to each microcantilever on the chip. Light propagates down a rib waveguide integrated into the microcantilever and, at the free end of the microcantilever, crosses a small gap. Light is captured in static asymmetric multimode waveguides that terminate in Y-branches, the outputs of which are imaged onto an InGaAs line scan …