Digital Commons Network^™

A Nonlinear Finite Element Model Of Cartilage Growth, Andrew Davol, Michael S. Bingham, Robert L. Sah, Stephen M. Klisch

Mechanical Engineering

The long range objective of this work is to develop a cartilage growth finite element model (CGFEM), based on the theories of growing mixtures that has the capability to depict the evolution of the anisotropic and inhomogeneous mechanical properties, residual stresses, and nonhomogeneities that are attained by native adult cartilage. The CGFEM developed here simulates isotropic in vitro growth of cartilage with and without mechanical stimulation. To accomplish this analysis a commercial finite element code (ABAQUS) is combined with an external program (MATLAB) to solve an incremental equilibrium boundary value problem representing one increment of growth. This procedure is repeated …

Exploring Potential U.S. Switchgrass Production For Lignocellulosic Ethanol, Ethan B. Davis, Henriette I. Jager, Tristram O. West, Robert D. Perlack, Craig C. Brandt, Stan D. Wullschleger, Latha M. Baskaran, Erin G. Wilkerson, Mark E. Downing, Carla A. Gunderson

United States Department of Energy: Publications

In response to concerns about oil dependency and the contributions of fossil fuel use to climatic change, the U.S. Department of Energy has begun a research initiative to make 20% of motor fuels biofuel based in 10 years, and make 30% of fuels bio-based by 2030. Fundamental to this objective is developing an understanding of feedstock dynamics of crops suitable for cellulosic ethanol production. This report focuses on switchgrass, reviewing the existing literature from field trials across the United States, and compiling it for the first time into a single database. Data available from the literature included cultivar and crop …

Subcellular Light Activation, Control And Manipulation Using A Dynamically Reconfigurable Nanopatterning System, Amruta Rajiv Joshi

Bioengineering Theses - Archive

Cellular communication is the basis of all cellular activities and functions. Cell signaling is crucial in the processes of tissue maintenance, tissue development and homeostasis. Errors in transmission or interpretation of these signals can result in the onset of diseases like cancer. Efforts have been made to probe into the communication between cells, and the extracellular signals that cells transmit to each other. There is however, a necessity to understand cell communication within the cellular components themselves and to be able to perform a nanoscale analysis of the cell organelle behavior. Many cellular mechanisms involve processes at the subcellular level, …

Microfluidic Flow Cytometer For High Throughput Label Free Cell Analysis, Sajal Chirvi

Bioengineering Theses - Archive

Microfluidic flow cytometer for high throughput label free cell analysis is proposed. Detection of cell morphology plays an important role in determination of state of health and diagnosis of many diseases such as sickle cell anemia, cancer, urine analysis, blood analysis etc. The platform proposed integrates label free cell analysis, microfluidic platform and high throughput imaging. Label free analysis helps in analyzing cells without altering cell/protein of interest and also allows biophysical characterization of living cells. Microfluidic platform used is fabricated from soft lithography. It mimics biological environment due to its channel confinement and is biocompatible. Being optically clear (PDMS), …

Study Of Normobaric Hyperoxia Effects During Focal Hypoxia-Ischemic Injury In Mice Using Optical Spectroscopy Measurements, Shereen Mohideen

Bioengineering Theses - Archive

Optical spectroscopy has seen tremendous growth and development in recent years and has been extensively used to characterize the optical properties of biological tissues. The purpose of this study is to investigate the values of oxygen saturation and concentration of hemoglobin in mice with focal hypoxic ischemia after being recovered in normobaric hyperoxia. Mice at five different age levels were used for this purpose, in order to see the effects of hyperoxia at different developmental stages of the brain; ischemia was induced in them by ligating their right carotid artery and subjecting them to hypoxic (8% oxygen) environment for half …

Studies Of Polymers In Fouling Release Coating Science, Haoran Chen

Master's Theses and Doctoral Dissertations

In chapter one, we describe our studies of the solubility properties of two biocides in F127 aqueous solutions. One is zinc omadine and the other is C9211. The partition coefficients of these two biocides were also determined from the analytical results.

In chapter two, we conducted phase related studies of a triblock copolymer, PEO400- PBO55-PEO400 in aqueous solution. The phase diagram features of PEO400-PBO55-PEO400 in water are compared with those of F127. We believe the lack of a lower gel to liquid transition boundary in this system is because of the relatively longer PEO segments relative to the PBO segment. …

Spatial Variability Of Radionuclide Distribution Coefficients At The Savannah River Site And The Sub-Surface Transport Implications, Kelly Grogan

All Theses

Distribution coefficients, Kd, were measured for a suite of gamma-emitting radionuclides in uncontaminated soils from the E-Area burial grounds at the Savannah River Site. The objectives of the study were to (1) characterize the spatial variability of Kd, (2) evaluate the effect of spatial variability on vadose zone transport, and (3) develop statistical models for predicting Kd from physical or chemical characteristics.
Equilibrium batch sorption tests were performed on 27 soil samples collected from depths ranging from 11 ft to 100 ft from the BGO-3A core with 241Am, 109Cd, 139Ce, 137Cs, 57Co, 60Co, 203Hg, 85Sr, and 88Y. Distribution coefficients were …

Ductile-Regime Machining Of Silicon Carbide And Quartz, Deepak Ravindra

Masters Theses

Silicon carbide (SiC) and quartz are one of the advanced engineered ceramic materials designed to operate in extreme environments. One of the main reasons for the choice of these materials is due to its excellent electrical, mechanical and optical properties that benefit the semiconductor, MEMS and optoelectronic industry respectively. Manufacturing these materials is extremely challenging due to its high hardness, brittle characteristics and poor machinability. Severe fracture can result when trying to machine SiC and quartz due to its low fracture toughness. However, from past and current research efforts, it has been proven that ductile regime machining of brittle materials …

Laboratory Evaluation Of Polycyclic Aromatic Hydrocarbon Biodegradation At A Former Tar Plant Site, Mihika Baruah

All Theses

A former tar plant site in the southeastern
U.S. is one of hundreds across the country that is contaminated with polycyclic
aromatic hydrocarbons (PAHs). The 2007
CERCLA Priority List of Hazardous Substances ranks PAHs as the eighth most
prominent hazardous substance at National Priority List sites. However, benzo(a)pyrene
is the only PAH that is regulated under the Safe Drinking Water Act, with a maximum
contaminant level of 0.2 µg/l. As with most sites, monitored natural
attenuation was the preferred bioremediation approach for this site, assuming
it could be shown that the PAHs were undergoing biodegradation. Field data from the site …

Hamilton-Jacobi-Bellman Equations And Approximate Dynamic Programming On Time Scales, John E. Seiffertt Iv, Suman Sanyal, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

The time scales calculus is a key emerging area of mathematics due to its potential use in a wide variety of multidisciplinary applications. We extend this calculus to approximate dynamic programming (ADP). The core backward induction algorithm of dynamic programming is extended from its traditional discrete case to all isolated time scales. Hamilton-Jacobi-Bellman equations, the solution of which is the fundamental problem in the field of dynamic programming, are motivated and proven on time scales. By drawing together the calculus of time scales and the applied area of stochastic control via ADP, we have connected two major fields of research.

Maximum Likelihood Methods In Biology Revisited With Tools Of Computational Intelligence, John E. Seiffertt Iv, Andrew Vanbrunt, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

We investigate the problem of identification of genes correlated with the occurrence of diseases in a given population. The classical method of parametric linkage analysis is combined with newer tools and results are achieved on a model problem. This traditional method has advantages over non-parametric methods, but these advantages have been difficult to realize due to their high computational cost. We study a class of Evolutionary Algorithms from the Computational Intelligence literature which are designed to cut such costs considerably for optimization problems. We outline the details of this algorithm, called Particle Swarm Optimization, and present all the equations and …

Issues On Stability Of Adp Feedback Controllers For Dynamical Systems, S. N. Balakrishnan, Jie Ding, F. L. Lewis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper traces the development of neural-network (NN)-based feedback controllers that are derived from the principle of adaptive/approximate dynamic programming (ADP) and discusses their closed-loop stability. Different versions of NN structures in the literature, which embed mathematical mappings related to solutions of the ADP-formulated problems called “adaptive critics” or “action-critic” networks, are discussed. Distinction between the two classes of ADP applications is pointed out. Furthermore, papers in “model-free” development and model-based neurocontrollers are reviewed in terms of their contributions to stability issues. Recent literature suggests that work in ADP-based feedback controllers with assured stability is growing in diverse forms.

Zeolite-Based Nanosized Ti02 Photocatalytic Paper For Antimicrobial Barrier And Toxin Passivation In Packaging: Design, Synthesis And Characterization, Seonghyuk Ko

Dissertations

This dissertation describes comprehensive studies, including design, preparation, characterization and evaluation, to develop an innovative zeolite-based nanosized TiO2photocatalytic paper for disinfection and disintegration of organic toxins.

A novel paper with high photocatalytic performance was successfully prepared using natural zeolite (clinoptilolite)-based nanosized TiO2 photocatalyst in a microparticle retention papermaking system. Photocatalytic material, from its sol-gel derived TiO2 colloids to its anchoring onto zeolite, has been designed, prepared and characterized. Prior to photocatalytic papermaking, the characteristics of sol-gel synthesized TiO2 nanoparticles from colloidal to nanopowder were investigated with various initial sizes of colloidal nanoparticles synthesized in the range of 2.5±0.1 nm and …

Design Of A Temperature Profiling System For Use In Thermal Processing Of Food Products, Linda Tarantino

Biological and Agricultural Engineering Undergraduate Honors Theses

The purpose of this study was to develop a thermal inspection system on a full scale meat and poultry product line. The system must withstand the production and sanitation environments and adapt to the many different products and conditions present on a common product line. By using this device, food processors will be able to measure the internal temperature of the product during its entire cooking process. This will provide certainty to food processors if the product reached the required internal temperature by USDA standards as well as proof of their processes.

Microwave Dielectroscopy Of Breast Tissue Phantoms In The 5.8-40 Ghz Range, Binh Tran

Electrical Engineering Undergraduate Honors Theses

Based on the high contrast in dielectric properties between the low-water-contain sample and the high-water-content one, we can determine whether the tissue sample is cancerous or normal. In order to make the measurement repeatable and convenient, some phantom materials, which have the same dielectric properties of human tissues, have been prepared. These phantom tissues are made from gelatin, water with honey syrup and Sodium Chloride (NaCl). In this project, we are going to measure and compare the dielectric properties of different types of phantom tissues by using focused beam antennas. The purpose of this project is to perform a systematic …

A Design Aid For Determining Width Of Filter Strips, Michael G. Dosskey, M. J. Helmers, Dean E. Eisenhauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Watershed planners need a tool for determining width of filter strips that is accurate enough for developing cost-effective site designs and easy enough to use for making quick determinations on a large number and variety of sites. This study employed the process-based Vegetative Filter Strip Model to evaluate the relationship between filter strip width and trap¬ping efficiency for sediment and water and to produce a design aid for use where specific water quality targets must be met. Model simulations illustrate that relatively narrow filter strips can have high impact in some situations, while in others even a modest impact cannot …

Oil Recovery Through Deemulsification Research : Separation Of Water From Emulsified Oil, Aaron Russell, Matthew S. Clay, Christopher A. Cox, Jessica E. Nichols, Summer Scott, Sirikarn Surawanvijit

Chemical Engineering Undergraduate Honors Theses

In an effort to improve the environment, there is a need to recover and reuse the oil and water components of lubricating emulsions used in copper drawing and rolling processes. The Freeport-McMoRan Copper and Gold Inc. copper rod mill located in El Paso, TX was chosen as the site location for this project. It is one of the largest rolling and drawing operation facilities in the world, and it meets the established criteria set by Project ORDER. A large facility generates an average of 8,400 gallons of spent lubricant per day. The WERC emulsion sample contains 98 v% water and …

Technical Concepts Related To Conservation Of Irrigation And Rain Water In Agricultural Systems, A. J. Clemmens, R. G. Allen, Charles M. Burt

BioResource and Agricultural Engineering

Forty percent of freshwater withdrawals in the United States are for irrigated agriculture, which contribute more than $50 billion to the economy. Increasing diversions of water for urban, environmental, and other uses will likely decrease water available to agriculture. Water conservation in agriculture is touted as a good method for minimizing the impact of reduced agricultural diversions on production. Because “wasted” water is often reused until it reaches the ocean, there are limitations to the true water savings that result from programs that aim to increase irrigation efficiency. True water savings can come from four areas: reduction of unnecessary evaporation …

Investigation Of A Photosynthetically Aerated Cathode In A Mfc, Derek Little

All Theses

A microbial fuel cell (MFC) creates an environment that facilitates the conversion of electron donor compounds into electrical current through the oxidizing powers of microbial growth. Within the anode of a MFC bacteria grow oxidizing organic compounds while in the cathode oxygen is reduced. The goal of a MFC is to achieve respiration under anaerobic conditions having electrodes serve as intermediate electron acceptor for bacteria in the anode and shuttle electrons through a circuit to the cathode reducing a terminal electron acceptor.
Waste from the biological production of hydrogen from agricultural peach was explored for use within the anode of …

Preparing, Characterizing, On-Line Digital Image Processing Of Residence Time Distribution And Modeling Of Mechanical Properties Of Nanocomposite Foams, Siew-Yoong Lee

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The objectives of this research were to prepare, characterize and to study the effects of organoclay and extrusion variables on the physical, mechanical, structural, thermal and functional properties of tapioca starch (TS)/poly(lactic acid) (PLA) nanocomposite foams. On-line digital imaging processing was used to determine residence time distribution (RTD). Adaptive neuro-fuzzy inference system (ANFIS) was used to model the mechanical properties of nanocomposite foams.

Four different organoclays (Cloisite 10A, 25A, 93A, 15A) were used to produce nanocomposite foams by melt-intercalation. The properties were characterized using Xray diffraction, scanning electron microscopy, differential scanning calorimetric, and Instron universal testing machine. The properties were …

Synthesis And Characterization Of Polyionic Hydrogels, Pooja Desai

Theses and Dissertations

In this study we describe novel polyionic dendrimer – PEG hydrogels for drug delivery. Hydrogels have a crosslinked insoluble network of polymer chains, which have found many applications including drug delivery and tissue regeneration. Dendrimers provide an ideal platform for drug delivery as they possess a well-defined highly branched nanoscale architecture with many reactive surface groups. Their highly clustered surface groups allow for targeted drug delivery and high drug payload to enhance therapeutic effectiveness. This study presented a new type of polyionic hydrogels based on dendrimers with potential applications in drug delivery and tissue engineering. Polyethylene glycol (PEG) with various …

Experimental Framework For The Position Control Of Magnetic Microfibers, Sriram Ravindren

All Theses

Magnetic microfibers have been developed in recent years with potential applications to a large number of fields, from MEMS to microfluidics to bio-chemical analyses. Magnetic microfibers based on polymer material like polypropylene and cellulose has been developed at Clemson University that are hollow cylindrical filaments internally coated with superparamagnetic nanoparticles. This internal coating provides the fiber with magnetic properties that allow them to be externally controlled using magnetic fields from a distance. These fibers can align with the external magnetic fields under constraints imposed by elastic properties and boundary conditions. Current work in this field is primarily focused on the …

Lidar System Model For Use With Path Obscurants And Experimental Validation, J. W. Giles, I. N. Bankman, R. M. Sova, T. R. Morgan, Donald D. Duncan, J. A. Millard, W. J. Green, F. J. Marcotte

Electrical and Computer Engineering Faculty Publications and Presentations

When lidar pulses travel through a short path that includes a relatively high concentration of aerosols, scattering phenomena can alter the power and temporal properties of the pulses significantly, causing undesirable effects in the received pulse. In many applications the design of the lidar transmitter and receiver must consider adverse environmental aerosol conditions to ensure the desired performance. We present an analytical model of lidar system operation when the optical path includes aerosols for use in support of instrument design, simulations, and system evaluation. The model considers an optical path terminated with a solid object, although it can also be …

50th Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 50th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Breckenridge, Colorado, July 27-31, 2008.

Design Process Modeling: Towards An Ontology Of Engineering Design Activities, Pavan Kumar

All Theses

An ontology of engineering design activities, called the Design Activity Ontology (DAO), is developed in this research. The DAO models 82 information flows and 25 design activities. These activities cover phases of the design process from conceptual phase through detail design phase. The ontology provides a formalized and structured vocabulary of design activities for consistency and exchange of design process models. The DAO enables design processes to be modeled, analyzed and optimized. The DAO is constructed using information flows identified in current design literature, commonly accepted engineering design textbooks, and an existing activity ontology. Specifically, the DAO is an extension …

Electrokinetic Transport In Micro- And Nano- Channels:A Study Examining Electrokinetic Energy Conversion And Dielectrophoretic Particle Separation, Christian Davidson

All Theses

New micro-fabrication techniques have allowed for the recent development of micro-scale lab on a chip devices which can be utilized for on chip biological analysis as well as electrokinetic energy conversion. This thesis aims to theoretically examine the current thermodynamic efficiency discrepancies in electrokinetic energy conversion devices as well as explore the potential for efficiency increase in a device which supports fluid slip. Also, a micro-fluidic lab on a chip device is fabricated and demonstrated to be capable of continuously separating multiple particles of 1μm, 5μm and 10μm out of a bulk solution. Our device employs a DC dielectrophoretic technique, …

Risedronate Prevents Early Bone Loss Resulting From Whole-Body Irradiation, Eric Livingston

All Theses

Osteoporosis is a condition characterized by a reduction in bone strength resulting in an overall increase in the risk of fracture. There are many factors that contribute to the development of this condition, including ionizing radiation exposure. Declines in bone volume and trabecular micro-architecture have been found following exposure to multiple types of radiation. Past research has implicated reduction of osteoblast function and changes to vasculature as the primary sources of bone deterioration. Recently, an early increase in osteoclast number was observed following exposure to low-energy X-rays, identifying an increase in resorption as a possible cause and potential target for …

Fpga Acceleration Of A Cortical And A Matched Filter-Based Algorithm, Kenneth Rice

All Theses

Digital image processing is a widely used and diverse field. It is used in a broad array of areas such as tracking and detection, object avoidance, computer vision, and numerous other applications. For many image processing tasks, the computations can become time consuming. Therefore, a means for accelerating the computations would be beneficial. Using that as motivation, this thesis examines the acceleration of two distinctly different image processing applications. The first image processing application examined is a recent neocortex inspired cognitive model geared towards pattern recognition as seen in the visual cortex. For this model, both software and reconfigurable logic …

Biomechanical Evaluation Of Two Methods Of Humeral Shaft Fixation, Joshua Catanzarite

All Theses

Biomechanical evaluations of fracture fixation devices attempt to determine implant performance by approximating the in vivo conditions. This performance is affected by many factors and relies on the complex bone-implant interface. Biomechanical tests can be designed in a variety of ways in order to evaluate device performance with respect to any number of these bone-implant interactions. Standardized tests, designed by groups such as the American Society for Testing and Materials (ASTM), are often designed either to determine the performance of a specific type of fixation device or for direct comparison between different devices. Additionally, many biomechanical evaluations are designed for …

Quantifying Antalgic Gait Knee Function Using Inertial Sensor Technology, William Mostertz

All Theses

The use of body-fixed inertial sensors to analyze human movement may prove useful in the medical field. Improving orthopaedic device design, diagnosing musculoskeletal disorders, and rehabilitation assessment could all benefit from a mobile gait analysis system based on inertial sensors. More specifically, patients recovering from lower limb corrective surgeries tend to adjust gait patterns to accommodate pain, a condition referred to as antalgic gait. Currently there is no quantitative method available to assess recovery for this patient population during post-operative management. A comparison of the inertial sensor system with the camera-based industry standard has confirmed it as a viable method …