Digital Commons Network^™

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 …

Artificial Neural Network For Spectrum Unfolding Bonner Sphere Data, Jia Hou

Masters Theses

The use of Bonner Sphere Spectrometer (BSS) is a well-established method of measuring the energy distribution of neutron emission sources. The purpose of this research is to apply the Generalized Regression Neural Network (GRNN), a kind of Artificial Neural Network (ANN), to predict the neutron spectrum using the count rate data from a BSS. The BSS system was simulated with the MCNP5 Monte-Carlo code to calculate the response to neutrons of different energies for each combination of thermal neutron detector and polyethylene sphere. One hundred and sixty-three different types of neutron spectra were then investigated. GRNN Training and testing was …

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, …

Modbus Implementation Using A Serial Link, Naresh Karnam

Masters Theses

Serial Communication is a process of sending one bit at a time, sequentially over a communication channel or a computer bus. RS-232 and RS- 484 are two such examples of the architecture of Serial Communication. This work primarily aims at establishing a communication channel between three entities namely the Controller also called the Console, the Relay Unit and a PC. This work aims at designing the communication model, using the Client-Server architecture and using the MODBUS protocol, as the standard for transmitting the bits in a Remote Terminal Unit (RTU) mode and for framing the characters. The MODBUS protocol also …

A Longest-Queue-First Signal Scheduling Algorithm With Quality Of Service Provisioning For An Isolated Intersection, Richard James Wunderlich

Masters Theses

In today's fast-paced society, the need to travel using automobiles is increasingly important. Aside from the road itself, the intersection is the most basic unit of a traffic system. As such, controlling the flow of traffic through intersections in an efficient manner has become a task of the utmost importance. The signal-scheduling algorithm described in this thesis is designed for just such a task. Concepts are drawn from the field of packet switching in computer networks and are applied to the traffic control problem. The method proposed utilizes a maximal weight matching algorithm to minimize the queue sizes at each …

The Detection Of Stress Corrosion Cracking In Natural Gas Pipelines Using Electromagnetic Acoustic Transducers, Austin P. Albright

Masters Theses

This thesis describes the refinement of a non-destructive, in-line inspection system sensor for the detection of stress corrosion cracks (SCCs) in natural gas pipelines. The sensors are prototype electromagnetic acoustic transducers (EMATs) for noncontact ultrasonic inspection. The focus areas discussed involve the statistically validated performance improvements achieved through the addition of 12 more features, the addition of Principal Component Analysis plus Linear Discriminant Analysis (PCA+LDA) to the classification algorithm, and most significantly the creating of a training set. The training set allowed PCA+LDA to be included in the classification algorithm, as well as allowing one set of no-flaw signature features, …

Effects On Level Flight Performance Of The Optimized Wind Deflector Modification For The Md-500 Helicopter, Adam Joseph Cowan

Masters Theses

This thesis investigates the effects of personnel wind deflector devices on the level flight performance of an MD-500D helicopter configured with external passenger provisions. Numerous helicopter organizations operate with external passenger configurations. These configurations result in personnel exposure to high winds and an increase in parasite drag. Level flight performance is degraded by the increase in parasite drag caused by the external passengers. Wind deflectors were mounted on the forward portion of the fuselage to protect external passengers from the effects of wind exposure (high wind loads and wind chill factor) by deflecting the wind away from the fuselage. The …

Investigation Of The Sidewall Boundary Layers In The Bidirectional Vortex Liquid Rocket Engine, Joshua W. Batterson

Masters Theses

To complement previous studies on the bidirectional vortex, we attempt to characterize viscous effects in both the axial and radial directions along the sidewall with standard asymptotic techniques. The actual boundary layer present in the chamber will be a composite of both axial and tangential shearing layers. Since the tangential velocity is completely dominant, we expect the defining characteristics of the composite boundary layer to be congruent with the tangential layer in both thickness and axial invariance. The analytic analysis is outlined first by, the formulation of the boundary layer equations via Prandtl’s method. Next, asymptotic techniques are applied to …

Impedance Matching And PspiceR Simulation Of One Atmosphere Uniform Glow Discharge Plasma (Oaugdp™) Reactor/Actuator Systems, Zhiyu Chen

Masters Theses

This thesis addresses two important issues relevant to One Atmosphere Uniform Glow Discharge Plasma (OAUGDP™) reactors and actuators ¾ impedance matching and PSpice^R simulation.

An OAUGDP™ reactor/actuator with the plasma energized can be modeled as a capacitor in parallel with a resistor. In addition, the non-ideality of the transformer between the RF power supply and the plasma reactor/actuator introduces an imaginary component in its impedance. Thus, the load of the RF power supply, as seen by its output terminals, is highly reactive. An impedance mismatch resulting from the absence of a matching network will cause a large reflected power …

A Study Of The Beginning Boundary Layer Influence On The Flow Field About A Two-Dimensional Automotive Model, Jonathan Gabriel Ford

Masters Theses

An experimental investigation was performed to analyze the beginning boundary layer produced on the floor of a subsonic wind tunnel and its influence on the flow field about a two-dimensional automotive model. Hot film anemometer measurements were taken in the test section of the wind tunnel operating under various inlet configurations. The use of a splitter plate and modifications to the contour of the inlet to the wind tunnel were then studied to find their affects on the height of the boundary layer in the wind tunnel test section. Finally, a 2-D automotive model was constructed with pressure taps along …

Evaluation Of Losses In Hid Electronic Ballast Using Silicon Carbide Mosfets, Lakshmi Reddy Gopi Reddy

Masters Theses

HID lamps are used in applications where high luminous intensity is desired. They are used in a wide range of applications from gymnasiums to movie theatres, from parking lots to indoor aquaria, from vehicle headlights to indoor gardening. They require ballasts during start-up and also during operation to regulate the voltage and current levels. Electronic ballasts have advantages of less weight, smooth operation, and less noisy over electromagnetic ballasts. A number of topologies are available for the electronic ballast where control of power electronic devices is exploited to achieve the performance of a ballast for lighting. A typical electronic ballast …

Investigations On Hydrocyclones For The Spallation Neutron Source, Lee Henry Hosack

Masters Theses

The hydrocyclone is commonly used to separate oil from water, and particulates from fluid streams in various process industries. Two-fluid hydrodynamic theory is used here to develop a model for hydrocyclone performance in the application of separation of helium bubbles larger than 30 micron in diameter from liquid mercury at system pressure near 1 bar. The application is related to high power liquid metal target development for proton beams used in spallation neutron sources.

Blast Resistant Design Of Steel Structures, Sarah Beth Janney

Masters Theses

The purpose of this study was to examine the load experienced by a steel blast cubicle from a surface blast test. An important objective was to determine the blast load experienced at different standoff distances and the blast resistance capability of the blast cubicle. Three cubicles with standoff distances of 20, 25, and 30ft respectively were simultaneously subjected to a 50lb TNT explosive. The manual Structures to Resist the Effects of Accidental Explosions, Army TM 5-1300 conservatively predicted the blast pressure loadings obtained from the pressure transducers mounted on the cubicles. Data collected from accelerometers was compared to results from …

Estimation Of Surface Temperature And Heat Flux Using Embedded Thermocouples, Jeffrey Daniel King

Masters Theses

This thesis investigates several new methods for estimating surface temperature and heat flux based on thermocouples embedded within the interior of a test article. The test apparatus was a Mach 2 axisymmetric rocket nozzle with probes embedded at depths of 1/8” and 1/4” from the inner surface of the nozzle at the throat and exit locations. Three methods for numerically estimating temperature and heat flux at the surface of the nozzle were considered: a one-thermocouple slab-coordinate method, a two-thermocouple slabcoordinate method, and a finite-element analysis (FEA) based on a one-dimensional cylindrical coordinate method. Comparisons between the methods, as well as …

Vascular Hemodynamics Cfd Modeling, Shashank Kiran Karra

Masters Theses

Three dimensional pulsatile blood flow CFD simulations in geometrically genuine normal and non-normal (aneurysm) human neck-head vascular systems nominally spanning the aortic arch to the circle of Willis has been performed and studied. CT scans of the human aortic arch and the carotid arteries were interpreted to obtain geometric data defining the boundary for a vascular CFD simulation. This was accomplished by reconstructing the surface from the anatomical slices and by imposing pertinent boundary conditions at the various artery termini. Following automated formation of a non-conformal CFD mesh, steady and unsteady laminar and low turbulent simulations were performed both for …

Universal Voltage Rate Sensor Interface, Jayanth Chakradhar Kruttiventi

Masters Theses

Measurement of heat flux is required in many aerospace and heat treatment applications. Temperature data collected at embedded sites are noisy especially when measurements are taken in hostile environments. The predicted heat flux, when based on the rate of change of temperature, is more accurate than using temperature data as the latter data form is ill-posed. In the context of heat flux prediction, calculating the rate of change of temperature involves differentiation, which is the primary source of ill-posed effects.

This work involves developing a universal voltage rate sensor interface that minimizes these effects and also improves the signal-to-noise ratio. …

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 …

Two-Phase Hydraulics State Identification Using Linear And Non-Linear Time Series Analysis: Distillation Column Flooding Sensor, Alok Maheshbhai Patel

Masters Theses

A novel sensor to detect and predict hydraulic flooding in the distillation column was developed in this research. High speed (1000 Hz) differential pressure data sets were collected across distillation trays. The distillation column at University of Tennessee, Knoxville (UTK) was the main research and demonstration site. The UTK column is 9 inches inside diameter, has 4 trays each of a different type not counting the reboiler. Many data sets were collected synchronously across the top tray (sieve tray) and across the next tray (bubble cap) from the top. Flooding always occurred on the sieve tray. To prove the application …

Fpga-Based Image Analysis System For Cotton Classing, Muhammad Imran Sharafat

Masters Theses

The design and implementation of an FPGA (field-programmable gate array) based image analysis system was undertaken to replace an older system whose components have become obsolete. Video from an analog camera is digitized by a video decoder. The data from the video decoder is stored in memory and then processed using an FPGA. The results are then transmitted over a universal serial bus (USB) to a host personal computer for additional processing. The system also controls the timing of a flash to correctly capture the images; it measures color and reflectance and is used to classify the quality of raw …

Virtual Modeling And Verification Of Air-Ride Truck Seat Using Multibody Dynamics For Whole Body Vibration Evaluation, Devdutt Nandkishore Shende

Masters Theses

To aid the tuning and optimization of the truck seat design to specific trucks and road profiles during the design phase, this study presents the development and validation of a virtual seat model. This study also assess the utility of the model for whole body vibrations evaluation.

The virtual dynamic seat model was developed in MSC. ADAMS/VIEW. The critical elements like the suspension mechanism, the airspring, dampers and seat cushion were modeled using tested data. To validate the performance of the virtual model, prototype tests were performed using the MTS 6-axis simulator. The modeling process was targeted to achieve a …

Uncertainty Analysis Of Advanced Fuel Cycles To Control Plutonium Inventories, Thomas Christopher Anderson

Masters Theses

This paper assesses the uncertainty associated with the utilization and implementation of advanced fuel cycles to control plutonium inventories. The specific fuel cycles investigated are a partially closed cycle utilizing MOX reactors and completely closed one-tier fuel cycles utilizing fast reactors. Multiple methods for assessing these uncertainties were utilized. A scenario approach that varied the time and number of the implementation of the advanced reactors was used. It was found that the implementation of 3 FR/yr with a CR of 0.5 could reduce the amount of Pu by over 36% in reference to building 3 LWR/yr. In addition to reducing …

Developing A Technique For Evaluating Weed-Specific Mapping Systems, Philip Brooks Allen

Masters Theses

Federal regulation and public awareness of agricultural chemical use have fueled precision agriculture research for the last decade. An extensive body of research on potential reduction of herbicide inputs by automated patch-spraying or site-specific management has developed. Two dominant methods have developed for site-specific application of herbicide. Map-based systems use predefined application maps to direct herbicide application and sensor-based systems use real-time weed sensors to identify and treat weeds as the sprayer moves through the field. Weed maps, generated for map-based application of herbicide are beneficial for out-of-field decision-making but are labor intensive to create and sensitive to many types …

A 64-Channel Mixed-Signal Data Acquisition System For A Solid-State High Efficiency Neutron Detector Array, Anthony Gene Antonacci

Masters Theses

This thesis presents the design of multiple analog and digital blocks required to implement a desired solid-state data acquisition system for the High Efficiency Neutron Detector Array (HENDA) project under the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). This system encloses and is an extension of prior work described in [1] and [2]. The first prototype chip, named Patara, contained a charge sensitive front-end amplifier [2], and a semi-Gaussian shaper with baseline restore circuitry [1]. Patara III, described in this thesis, involved the addition of the following system components; two comparators, a selectable synchronous/asynchronous digital …

Cfd Characterization Of Automotive Inflator-Generated Gas Distribution Process, Scott Alan Lusted

Masters Theses

This thesis outlines the application of Computational Fluid Dynamics to the characterization of the gas distribution process inherent in automotive gas generators. The gas distribution process is important to understand as it greatly influences the overall performance of the device and its competitiveness in the marketplace. Presently, there is limited analysis that has been conducted on the gas generators. The current method involves conducting experiments using prototype hardware and high speed video to capture the flow field. This approach has proven to be useful; however, it lacks the ability to thoroughly study the fluid dynamics. Furthermore, the analysis has to …

Inverse Kinematics Based On Fuzzy Logic And Neural Networks For The Wam-Titan Ii Teleoperation System, Joong-Kyoo Park

Masters Theses

The inverse kinematic problem is crucial for robotics. In this paper, a solution algorithm is presented using artificial intelligence to improve the pseudo-inverse Jacobian calculation for the 7-DOF Whole Arm Manipulator (WAM) and 6-DOF Titan II teleoperation system. An investigation of the inverse kinematics based on fuzzy logic and artificial neural networks for the teleoperation system was undertaken. Various methods such as Adaptive Neural-Fuzzy Inference System (ANFIS), Genetic Algorithms (GA), Multilayer Perceptrons (MLP) Feedforward Networks, Radial Basis Function Networks (RBF) and Generalized Regression Neural Networks (GRNN) were tested and simulated using MATLAB. Each method for identification of the pseudo-inverse problem …

Analysis And Characterization Of A Sige Bicmos Low Power Operational Amplifier, Archana Yarlagadda

Masters Theses

Integrated circuit design for space applications can require radiation immunity, cryogenic operation and low power consumption. This thesis provides analysis and characterization of a SiGe BiCMOS low power operational amplifier (op amp) designed for lunar surface applications. The op amp has been fabricated on a commercially available 0.35-micron Silicon-Germanium (SiGe) BiCMOS process. The Heterojunction bipolar transistors (HBT) available in the SiGe process have been used in this op amp to take advantage of the total ionizing dose (TID) irradiation immunity and superb cryogenic operation, along with PMOS devices that show better TID immunity than their NMOS counterparts. The key features …

A Generalized Hamiltonian-Based Algorithm For Rigorous Nonequilibrium Molecular Dynamics Simulation In The Nvt Ensemble, Joseph Gerald Leo Rajkumar

Masters Theses

Using a recently developed, methodical, Hamiltonian-based procedure, we derive rigorous algorithms for nonequilibrium molecular dynamic (NEMD) simulation in the NVE and NVT ensembles. We demonstrate that the equivalence of the kinetic temperature and configurational temperatures that exists at equilibrium is maintained in nonequilibrium states, given the proper nonequilibrium expression (in the microcanonical ensemble). Specifically, we apply the procedure to the p-SLLOD algorithm, which allows for rigorous NEMD simulation in the presence of an arbitrary, externally imposed flow field. The resulting algorithms are general in that they apply in the presence or absence of external fields in addition to the imposed …

Evaluation Of Head Linear And Rotational Acceleration Response To Various Linear-Induced Impact Scenarios, Robert Paul Roy

Masters Theses

Incidents resulting in head injury generally involve components of both linear and rotational motion. The protection of the head from injury most often comes from the use of some form of helmet. Helmets currently are designed only to protect the head from linear accelerations. Recent research involving the analysis of concussion in professional football suggested that linear accelerations are more consistent in the prediction of concussion, with the resultant rotational accelerations correlating to the peak linear accelerations of the impact.

This research proposes to determine if the situation of the head impact has an effect on the correlation of the …

A Standard Cmos Compatible Bandgap Voltage Reference With Post-Process Digitally Tunable Temperature Coefficient, Sam D. Caylor

Masters Theses

An essential element of most robust analog/mixed-signal systems is a stable and precise bandgap voltage reference (BGR). CMOS compatible BGR circuits are generally limited by variability in output drift over temperature due to process variations. In this work a CMOS BGR is developed that provides simple, digitally-controlled post-process (i.e., post fabrication) trimming. The trimming is achieved through MOSFET switches used to adjust a current gain factor for the thermal voltage referenced current within the BGR circuit. This current is proportional to absolute temperature (PTAT). The PTAT current is injected into a series connected resistor and diode to ultimately provide an …

Using Multivariate Analysis Of Geochemical Data To Better Define Hydrologic Interfaces In Surface Water - Groundwater Systems, Candice Ann Owen

Masters Theses

Groundwater-surface water interactions have been shown to be important to flow generation and stream chemistry in upland catchment environments. These areas, however, are often difficult to access making the implementation of standard hydrological surface and subsurface monitoring equipment and characterization procedures impractical, arduous and in many cases impossible due to the nature of the terrain and also regulatory guidelines for protected areas. By collecting surface water samples at distinct water contribution sites to a headwater stream, areas of groundwater influence were inferred and a hydrochemical conceptual model of a small basin was created.

The objectives of this research were to …