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Identification And Quantification Of Cotton Yield Monitor Errors, Jason Clay Head Dec 2009

Identification And Quantification Of Cotton Yield Monitor Errors, Jason Clay Head

Masters Theses

Cotton yield monitors are an important part of a precision agriculture program and are becoming widely used by cotton producers for making management decisions. Members of the cotton industry have shown interest in using cotton yield monitors for collecting data from production scale variety yield trials (experiments that test yield performance for numerous varieties). Weighing boll buggies are the current industry standard for measuring yield in variety trials. This process is time consuming and requires extra equipment and labor. The ability to use a yield monitor for measuring yield would streamline variety trial harvesting. Recommendations for the Ag Leader cotton …


Insight Into The Gating Mechanism Of Mechanosensitive Ion Channels Using A Simple Structure: A Step In The Analysis Of Commotio Cordis, Sumeet Kaul Aug 2009

Insight Into The Gating Mechanism Of Mechanosensitive Ion Channels Using A Simple Structure: A Step In The Analysis Of Commotio Cordis, Sumeet Kaul

Masters Theses

Mechanosensation in cells is a well known phenomenon that is associated with cellular responses to force. Our knowledge of the trigger mechanism of this phenomenon is, however, limited. Earlier studies in this field have used atomic simulations, which although being accurate, are limited in their feasibility in multi-length scenarios like a mechanosensitive channel that undergoes micro-level changes in the composition of the protein to cause a macro-level change in the state of a biological structure such as the muscle. Finite Element Analysis has been used in various engineering fields to study the mechanical response of complex structures. The current study …


Development Of A Computational Model To Predict The In Vivo Contact Mechanics Of Modern Total Knee Arthroplasty, Adrija Sharma Dec 2008

Development Of A Computational Model To Predict The In Vivo Contact Mechanics Of Modern Total Knee Arthroplasty, Adrija Sharma

Doctoral Dissertations

This dissertation focuses on the development of a computationally efficient and fast method that incorporates the kinematics obtained from fluoroscopy and extends it to the prediction of the in-vivo contact mechanics at the femoro-tibial articulation in modern knee implants for the deep knee bend activity. In this endeavor, this dissertation deals with the use of an inverse dynamic rigid body model characterizing the slip and roll behavior observed in the femoro-polyethylene articulation and a coupled deformation model where the polyethylene in knee implants are modeled as hexahedral discrete element networks. The performance of this method is tested by comparing force …


The Future Of The Operating Room: Surgical Preplanning And Navigation Using High Accuracy Ultra-Wideband Positioning And Advanced Bone Measurement, Brandon C. Merkl Dec 2008

The Future Of The Operating Room: Surgical Preplanning And Navigation Using High Accuracy Ultra-Wideband Positioning And Advanced Bone Measurement, Brandon C. Merkl

Doctoral Dissertations

This dissertation embodies the diversity and creativity of my research, of which much has been peer-reviewed, published in archival quality journals, and presented nationally and internationally. Portions of the work described herein have been published in the fields of image processing, forensic anthropology, physical anthropology, biomedical engineering, clinical orthopedics, and microwave engineering.

The problem studied is primarily that of developing the tools and technologies for a next-generation surgical navigation system. The discussion focuses on the underlying technologies of a novel microwave positioning subsystem and a bone analysis subsystem. The methodologies behind each of these technologies are presented in the context …


Synergistic Effect Of Retinoic Acid, Nerve Growth Factor And Laminin For Enhanced Neurite Extension, Shrarath Ashwin Sriman Dec 2008

Synergistic Effect Of Retinoic Acid, Nerve Growth Factor And Laminin For Enhanced Neurite Extension, Shrarath Ashwin Sriman

Masters Theses

Peripheral Nerve Injury is one of the most common and serious traumatic injuries. About 300,000 cases of peripheral nerve injury are reported annually in Europe and another 50,000 procedures performed annually in the United States. Peripheral nerve injury can lead to lifelong disability and also death in severe cases. Repair techniques remain a major challenge because of lack of efficient regeneration. Though techniques like autografts are highly efficient, they face a lot of drawbacks. Alternate methods focus on the use of growth supporting and enhancement components in nerve guidance channels. Current research necessitates the use of a combination of compounds …


Flow And Transport In Unsaturated Porous Media: Fractal Modeling, Analytical Solutions And Experimentation, Abdullah Cihan May 2008

Flow And Transport In Unsaturated Porous Media: Fractal Modeling, Analytical Solutions And Experimentation, Abdullah Cihan

Doctoral Dissertations

This dissertation consists of five parts, each describing a specific topic of unsaturated flow and transport. The first three parts describe the development of soil hydraulic function models with the effects of partial drainage by using fractal and probabilistic approaches. During drainage of a porous medium, both the pore size distribution and the connectivity of pores determine the drained pore volume as function of suction. New analytical expressions were presented for the water retention (part 1), intrinsic permeability (part 2), and relative permeability (part 3) functions. Predictions based on the analytical models are compared with estimates of the intrinsic permeability …


A Study Of Irrigation, Fertigation And Plasticulture In Burley Tobacco, With A Focus On Yield, Quality And Tsna Reduction, Eric F. Caldwell May 2008

A Study Of Irrigation, Fertigation And Plasticulture In Burley Tobacco, With A Focus On Yield, Quality And Tsna Reduction, Eric F. Caldwell

Masters Theses

Nitrogen fertilization is important in attaining high yielding, quality tobacco. However, practices that use excessive N can be uneconomical, threaten the environment and produce leaves that are high in nitrates. Leaves high in nitrates have been positively correlated with leaves that are high in tobacco specific nitrosamines (TSNA), which are considered potent carcinogens. Competition from cheaper, foreign leaf, increasing costs of fertilizers and new market structures which show purchasers seeking low TSNA leaf demand that producers become more efficient in their N use. The objective of this study is an examination of burley (TN 90) and dark (KY 171) tobacco …


Ultra-Wideband Frequency Surgical Navigation Probe, Stuart J. Deaderick Apr 2008

Ultra-Wideband Frequency Surgical Navigation Probe, Stuart J. Deaderick

Chancellor’s Honors Program Projects

No abstract provided.


Mems Capacitive Strain Sensing Elements For Integrated Total Knee Arthroplasty Prosthesis Monitoring, Boyd Mccutchen Evans Iii Dec 2007

Mems Capacitive Strain Sensing Elements For Integrated Total Knee Arthroplasty Prosthesis Monitoring, Boyd Mccutchen Evans Iii

Doctoral Dissertations

Measuring the in vivo load state of Total Knee Arthroplasty (TKA) components is required to understand the structural environment and wear characteristics of the devices. The ability to acquire this information gives tremendous insight into the mechanics of the joint replacement prosthesis. Data corresponding to normal loads, in-plane loads, shear loads, load center, contact area, and the rate of loading is needed to fully understand the kinematics and kinetics of the orthopedic implant. In this research, a novel sensing system has been developed which is capable of fully characterizing three-dimensional strain and stress at a single location.

Capacitance-based sensors were …


Theoretical Modeling And Experimental Validation Of In Vivo Mechanics For Subjects Having Variable Cervical Spine Conditions, Fei Liu Dec 2007

Theoretical Modeling And Experimental Validation Of In Vivo Mechanics For Subjects Having Variable Cervical Spine Conditions, Fei Liu

Doctoral Dissertations

The objective of this study was to use the state-of-art 3D-to-2D registration technologies including fluoroscopic, CT and MRI methods to analyze 2D and 3D in vivo kinematics of the whole cervical spine under variable conditions; and use inverse dynamic model based on Kane’s dynamics to predict their 2D and 3D in vivo interactive contact and muscular forces. Totally, forty patients (ten having normal cervical spines, ten having degenerative cervical spines, ten having anterior cervical decompression and fusion (ACDF), and ten having cervical artificial disc replacement (CADR)) were enrolled into 2D study and three patients (one having normal cervical spines, one …


Characterization Of A Biomimetic Calcium-Deficient Hydroxyapatite-Bacterial Cellulose Composite, Stacy Hutchens Dec 2007

Characterization Of A Biomimetic Calcium-Deficient Hydroxyapatite-Bacterial Cellulose Composite, Stacy Hutchens

Doctoral Dissertations

Bone is the second most implanted tissue next to blood causing approximately 2.2 million people to receive bone grafts each year. Developing safe synthetic bone grafts allows quick and safe restoration of bone function while avoiding the surgical risks associated with bone autografting (self donation), and risks of disease transmission and immunogenic response associated with allografts (bone donated from other humans) and xenografts (grafts derived from animal tissue). This dissertation entails the study and development of a novel potential synthetic bone graft consisting of a composite of calcium-deficient hydroxyapatite (CdHAP) biomimetically deposited in a bacterial cellulose (BC) hydrogel.

To determine …


Applied Fourier Transform Near-Infrared Techniques For Biomass Compositional Analysis, Lu Liu Dec 2007

Applied Fourier Transform Near-Infrared Techniques For Biomass Compositional Analysis, Lu Liu

Masters Theses

A new method for rapid chemical analysis of lignocellulosic biomass was developed using Fourier transform near-infrared (FT-NIR) spectroscopic techniques. The new method is less time-consuming and expensive than traditional wet chemistry. A mathematical model correlated FT-NIR spectra with concentrations determined by wet chemistry. Chemical compositions of corn stover and switchgrass were evaluated in terms of glucose, xylose, galactose, arabinose, mannose, lignin, and ash. Model development evaluated multivariate regressions, spectral transform algorithms, and spectral pretreatments and selected partial least squares regression, log(1/R), and extended multiplicative signal correction, respectively. Chemical composition results indicated greater variability in corn stover than switchgrass, especially among …


Image And Sieve Analysis Of Biomass Particle Sizes And Separation After Size Reduction, Yuechuan Yang Dec 2007

Image And Sieve Analysis Of Biomass Particle Sizes And Separation After Size Reduction, Yuechuan Yang

Masters Theses

Improved physical separation of biomass concentrates higher-value components, returns unused plant components to the soil, and provides a more efficient platform for downstream industrial users. Sieving and Image Analysis (IA) were studied to evaluate biomass particle sizes, particle size distribution, and potential separation of biomass materials. Switchgrass, wheat straw, and corn stover were used in the study. Particles prepared by a knife mill equipped with various screen sizes were subject to sieving test and IA. Results showed that all three biomass materials would be analyzed using the fast, easy and accurate IA. Biomass particle physical properties, such as length, width, …


Development Of The Telemetrical Intraoperative Soft Tissue Tension Monitoring System In Total Knee Replacement With Mems And Asic Technologies, Gary To Dec 2007

Development Of The Telemetrical Intraoperative Soft Tissue Tension Monitoring System In Total Knee Replacement With Mems And Asic Technologies, Gary To

Masters Theses

The alignment of the femoral and tibial components of the Total Knee Arthoplasty (TKA) is one of the most important factors to implant survivorship. Hence, numerous ligament balancing techniques and devices have been developed in order to accurately balance the knee intra-operatively. Spacer block, tensioner and tram adapter are instruments that allow surgeons to qualitatively balance the flexion and extension gaps during TKA. However, even with these instruments, the surgical procedure still relies on the skill and experience of the surgeon. The objective of this thesis is to develop a computerized surgical instrument that can acquire intra-operative data telemetrically for …


Design And Evaluation Of A Non-Intrusive Corn Population Sensor, Haizhou Li Aug 2007

Design And Evaluation Of A Non-Intrusive Corn Population Sensor, Haizhou Li

Doctoral Dissertations

Specific objectives of this study were to develop, prototype, and test a corn population sensor. Both intrusive mechanical and non-intrusive capacitive techniques have been used to develop the stalk population sensors in previous research. However, neither could generate consistent performance. The mechanical method required high maintenance and resulted in significant underestimations of stalk counts. The performance of capacitive systems was limited by inadequate sensing distance, especially at low stalk moisture levels.

In this research, the sensitivity of the capacitive sensor was optimized for corn stalks. This system utilized a single-sided capacitive sensor, Wien bridge oscillator, phase-locked loop, and an operational …


Risk Analysis Of Decentralized Wastewater Design Flows, Patrick Andrew Dobbs May 2007

Risk Analysis Of Decentralized Wastewater Design Flows, Patrick Andrew Dobbs

Masters Theses

Decentralized wastewater treatment systems are often designed at flows of either 284 L/person/d (75 gal/person/d) or 568 L/bedroom/d (150 gal/bedroom/d). Water use data suggest that designing systems at these flow rates can lead to overly conservative designs. A study quantifying the risk of failure (exceeding a system design flow) was needed to create a design basis for future systems. The objectives of the study were to quantify the risk of failure of decentralized system design flows depending on the number of residences served by a system and to develop new guidelines for design flows of cluster systems based on quantifiable …


Utilizing An Ultrasonic Device To Model The Lumbar Spine While Driving A Tractor Trailer, Gretchen Marie Hinton May 2007

Utilizing An Ultrasonic Device To Model The Lumbar Spine While Driving A Tractor Trailer, Gretchen Marie Hinton

Masters Theses

Low back pain is a common occupational effect of the long term driving of vehicles. The sonoSens® Monitor ultrasonic device was utilized to model lumbar spinal motions while driving a tractor trailer. Further data was collected to determine if acceleration from a seat pad and EMG data correlated with the driver’s movements.

Three testing bouts were completed and analyzed for this study. For each test the driver drove a 1998 Peterbuilt 379 fitted with a National Seating 2000 seat. One driver was used for all three tests.

Data analysis was accomplished with the sonoSens® Analyzer and Microsoft® Excel software. The …


A Simulation Model For Predicting Surface Tension In Condensate Films, Allison Dawn Lewis May 2007

A Simulation Model For Predicting Surface Tension In Condensate Films, Allison Dawn Lewis

Masters Theses

The thesis presents a mathematical model for predicting surface tension in condensate films. The approach taken to this study is different from how surface tension is normally approached. Surface tension is primarily determined through laboratory measurements. This work shows how it can be determined mathematically based on the formulation of bonding energy between atoms as described by the Lennard-Jones potential.

The results are used to predict the surface tension of a selected group of elements and molecules. Predictions from the model compare favorably with the documented surface tension values of the selected elements. However, the model does deviate somewhat from …


Environmental Effects On Driver Acceleration Exposure, Shekhar Khanal Aug 2006

Environmental Effects On Driver Acceleration Exposure, Shekhar Khanal

Masters Theses

The European Union has developed a set of standard for the exposure to whole body vibration measured by acceleration. For manufacturers to meet this directive, it is essential to understand the levels of exposures that are common among long-haul vehicle drivers.

Many factors can influence the exposure levels. Generally, all the European vehicles are the cab-over design. Each vehicle manufacturer has provided a combination of truck and cab suspensions in addition to the air-ride seating that is standard on the vehicles. The road quality, driver speeds, and time of daily work can have variation from country to country. The determination …


Modification And Evaluation Of Continuous Roll Prediction Model For Front Drive Mowers, Xinyan Wang Dec 2005

Modification And Evaluation Of Continuous Roll Prediction Model For Front Drive Mowers, Xinyan Wang

Doctoral Dissertations

The recently approved ASAE Standard S547 “Tip-Over Protective Structure (TOPS) for Front Wheel Drive Turf and Landscape Equipment” addressed a continuous roll prediction model for Roll-Over Protective Structure (ROPS) design. The existing model described in this Standard did not take into account the influence of the mower deck on the rollover behavior. In order to evaluate the accuracy of the original model, according to the ASAE S547 requirement, a 4.05 meters long and 3.42 meters wide slope of 35 degrees was constructed at the University of Tennessee. Lateral upset tests for Deere F925 front drive mower with regular and inverted …


Vegetative Recovery Of Military Vehicle Impacts At Fort Lewis, Wa, Katie Jean Simmons May 2004

Vegetative Recovery Of Military Vehicle Impacts At Fort Lewis, Wa, Katie Jean Simmons

Masters Theses

Vehicles driven off-road damage the soil and vegetation on the terrain, which can cause soil erosion and degradation of the landscape. This type of damage occurs on military installations due to training. Military training lands must be managed in an attempt to minimize the overall impacts of training on the terrain. The Army Training and Testing Area Carrying Capacity (ATTACC) is a model used by the U.S. Army to manage their training lands. Methods of determining the impacts produced by a vehicle and subsequent vegetative recovery have been used at Fort Lewis, WA for the Light Armored Vehicle (LAV). The …


An Analysis Of Liquid Aluminum Sulfate (Alum) Use In Broiler Production Houses To Control In-House Ammonia (Nh3) Concentrations And Naturally-Occurring Salmonella And Campylobacter; The Development Of An Nh3 Emission Factor For A Typical Tennessee Broiler House., Kenneth A. Armstrong Dec 2003

An Analysis Of Liquid Aluminum Sulfate (Alum) Use In Broiler Production Houses To Control In-House Ammonia (Nh3) Concentrations And Naturally-Occurring Salmonella And Campylobacter; The Development Of An Nh3 Emission Factor For A Typical Tennessee Broiler House., Kenneth A. Armstrong

Masters Theses

No abstract provided.


Instrumented Self-Propelled Sprayer To Determine Dynamic Boom Effects On Droplet Application Uniformity, Hong Young Jeon Dec 2003

Instrumented Self-Propelled Sprayer To Determine Dynamic Boom Effects On Droplet Application Uniformity, Hong Young Jeon

Masters Theses

A self-propelled sprayer with a 27-m boom was instrumented to measure inadvertent boom movement and acceleration during field operation to quantity application uniformity. The instrumentation system was developed to monitor boom end heights, accelerations, and sprayer longitudinal position along a track. Acceleration measures included longitudinal (x), vertical (y), and transverse (z) components at the sprayer vehicle rear, boom center, and at each boom end. A PC-based data acquisition system polled sensors at 2.5 kHz. Software-implemented, 2nd-order Butterworth band pass (0.1 to 15 Hz) filtering of raw data reduced signal noise. Y-accelerations at the boom center ranged from 1.5 …


A Distributed Control System For Priority-Based Site-Specific Irrigation, Fabio Rodrigues De Miranda Aug 2003

A Distributed Control System For Priority-Based Site-Specific Irrigation, Fabio Rodrigues De Miranda

Doctoral Dissertations

Site-specific irrigation enables maximizing yields and water use efficiency for fields with variation in soil water availability. Distributed control for fixed irrigated systems, with controllers close to the sensors and actuators in the field, is easier to install and maintain, and less susceptible to damage by lightning strikes compared to centralized control, but is only economically viable with affordable, low-power controllers. A low cost, solar-powered, feedback irrigation controller for distributed control of fixed irrigation systems was developed and tested. The system used soil water potential measurements to control the amount of water applied to each specific zone of a field. …


Delineation Of Management Units For Site-Specific Irrigation.”, Carlos Wagner Oliveira Aug 2003

Delineation Of Management Units For Site-Specific Irrigation.”, Carlos Wagner Oliveira

Doctoral Dissertations

Variability of soil properties in many fields is too great for a whole field to be effectively managed with a uniform application of irrigation water. Consequently, a decision must be made for irrigation management about which areas in the field should be treated differently or grouped. A decision-making framework was developed to determine whether site-specific irrigation management would be cost effective for selected fields. The framework is designed to find the best field layout in terms of water management, and tests the hypothesis that there is a particular field management layout that maximizes net return. As part of the framework, …


Interpolation Of Spatial Surfaces And Inferring Subsurface Transitions Using Electrical Conductivity, Robert Claborne Wilson Aug 2003

Interpolation Of Spatial Surfaces And Inferring Subsurface Transitions Using Electrical Conductivity, Robert Claborne Wilson

Masters Theses

Precision agriculture techniques are becoming more popular within the agriculture community as producers demand more return from an ever-decreasing amount of farmland. Increased environmental regulations are forcing farmers to reduce the input of fertilizers and agrochemicals on their crops. Innovative techniques in precision agriculture are enhancing traditional decision-making processes by offering multiple layers of data for a production field. It is difficult to determine the complex interactions that exist between factors affecting crop growth and the resultant management decisions. Strategies in precision agriculture attempt to modify customary practices in order to address the known variability of field conditions. This case …


Molecular Characterization Of The T(4;9)12gso Mutation And Analysis Of The Associated Fitness, Skeletal, And Lymphoproliferative Phenotypes, Laura Ray Chittenden Aug 2002

Molecular Characterization Of The T(4;9)12gso Mutation And Analysis Of The Associated Fitness, Skeletal, And Lymphoproliferative Phenotypes, Laura Ray Chittenden

Doctoral Dissertations

The t(4;9)(B3;E3.2)12Gso reciprocal translocation is an autosomal recessive mouse mutation involving chromosome 4, band B3 (Mmu4B3) and chromosome 9, band E3.2 (Mmu9E3.2). The most striking phenotype of the 12Gso homozygote involves axial skeleton deformities, resulting in significant shortening of body length, scoliosis, displaced hips and kinky tails. Homozygous animals are significantly smaller than normal littermates and frequently exhibit early lethality, as many of the mutants perish by 1 day postnatal, and many others do not survive the three weeks to weaning age. Homozygous 12Gso mice also develop an unusual bone marrow defect that closely resembles leukemia. The penetrance of the …


Comparative Gene Mapping In Baboon (Papio) Species, Kathleen Lou Moore Thiessen Jun 1986

Comparative Gene Mapping In Baboon (Papio) Species, Kathleen Lou Moore Thiessen

Doctoral Dissertations

Gene mapping in nonhuman mammalian species is a field of increasing importance in man's efforts to understand genome organization, to develop animal models for human genetic diseases, and to investigate phylogenetic relationships and evolutionary mechanisms. The primates are of particular interest in these studies because of their morphological and physiological similarities to man. The availability and convenient size of the baboons (Papio species) make them the primates of choice for various areas of research having applications to man. The baboons also appear to have many chromosomal and genetic homologies to man as well as to the other primates, although …


X-Ray-Induced Specific-Locus Mutation Rates In Newborn And Young Mice, Paul Bruce Selby Aug 1972

X-Ray-Induced Specific-Locus Mutation Rates In Newborn And Young Mice, Paul Bruce Selby

Doctoral Dissertations

The specific-locus mutation frequency resulting from 300 R of acute X irradiation has been determined for the germ cells present in male mice at 0, 2, 4, 6, 8, 10, 14, 21, 28, and 35 days of age and also for female mice at 0 days of age, Sample size was much larger for the males irradiated on day 0 than for other age groups but in all groups it was large enough to insure that an extremely high rate would be noticed. At 35 days of age the testis is histologically similar to that of the adult. It was …