Engineering Commons^™

Evaluation Of The Flail Space Model Utilizing Event Data Recorder Technology, Douglas John Gabauer

Theses and Dissertations

Developed in the early 1980's, the flail space model has become the standard method for estimating occupant risk in full-scale crash tests involving roadside safety features. The widespread availability of airbags and increased seat belt usage rates in today's vehicle fleet, however, raise serious questions regarding the validity of the model. Recent implementation of Event Data Recorder (EDR) technology in a number of late model vehicles presents a different perspective on the assessment of the validity of occupant risk based on the flail space model. EDRs are capable of electronically recording data such as vehicle speed, brake status and throttle …

Development Of An Augmented Haptic Control For In-Vehicle Law Enforcement Applications, Edward R. Guest Iii

Theses and Dissertations

Typical police vehicles are filled with as much technology as the department can afford. Everything from the newest digital camera system to a simple entertainment radio is within the reach of an officer. Currently, most of these systems are installed without any consideration toward the other systems or the interaction required between the driver and the car. The lack of a systems approach in the installation has spawned a project to look at the safety and overall system installation in the New Jersey State Police vehicles.

The research presented in this thesis suggests consolidation of the various controls into one …

Hdl Implementation Of A Controller Area Network Node, Anthony Richard Marino

Theses and Dissertations

With increasing technology inside automobiles, especially law enforcement vehicles, there is a growing need for centralized wiring and device interconnection methods. Each new technology, such as GPS navigation units and in-vehicle video systems, includes a corresponding wiring harness that needs installation. The summation of all these hardwired technologies leads to large volumes of wire that negatively affect safety, power demands, and future design opportunities. A new trend among automotive manufacturers is to design and implement innovative networks that allow for shared communications between technologies.

This thesis presents the design, development, and implementation of an in-vehicle network that will centralize connections …

Spatially Varying Threshold Models For The Automated Segmentation Of Radiodense Tissue In Digitized Mammograms, Richard Edson Eckert Iii

Theses and Dissertations

The percentage of radiodense (bright) tissue in a mammogram has been correlated to an increased risk of breast cancer. This thesis presents an automated method to quantify the amount of radiodense tissue found in a digitized mammogram. The algorithm employs a radial basis function neural network in order to segment the breast tissue region from the remainder of the X-ray. A spatially varying Neyman-Pearson threshold is used to calculate the percentage of radiodense tissue and compensate for the effects of tissue compression that occurs during a mammography procedure. Results demonstrating the efficacy of the technique are demonstrated by exercising the …

Multi-Sensor Data Fusion Using Geometric Transformations For The Nondestructive Evaluation Of Gas Transmission Pipelines, Philip James Kulick

Theses and Dissertations

Nondestructive evaluation (NDE) plays a vital component in the operation and maintenance of large infrastructure such as gas transmission pipelines, nuclear power plants, aircraft, bridges and highways, etc. As this infrastructure continues to age it is essential that the inspection techniques reliably and accurately predict the integrity of these systems. No single NDE method is capable of inspecting all types of anomalies and extracting all required information – a combination of methods must be used and the resulting data fused. Moreover, newer systems that are developed are often made of composite materials that include metals and dielectrics. One interrogation modality …

Wind Scatterometry With Improved Ambiguity Selection And Rain Modeling, David W. Draper

Theses and Dissertations

Although generally accurate, the quality of SeaWinds on QuikSCAT scatterometer ocean vector winds is compromised by certain natural phenomena and retrieval algorithm limitations. This dissertation addresses three main contributers to scatterometer estimate error: poor ambiguity selection, estimate uncertainty at low wind speeds, and rain corruption. A quality assurance (QA) analysis performed on SeaWinds data suggests that about 5% of SeaWinds data contain ambiguity selection errors and that scatterometer estimation error is correlated with low wind speeds and rain events.

Ambiguity selection errors are partly due to the "nudging" step (initialization from outside data). A sophisticated new non-nudging ambiguity selection approach …

Selecting Appropriate Product Concepts For Manufacture In Developing Countries, Danielle Johnson

Theses and Dissertations

There is a noticeable lack of production of indigenously engineered and manufactured products in Less Developed Countries (LDC's). Few products developed in these LDC's could be viable in competitive markets or even sold as components and supplies to other manufacturers of competitive goods. Assumintg that these less developed countries do not innovate and manufacture because they cannot, the next logical question to ask is why can they not?

This thesis looks at the problems of manufacture and design in LDC's from the standpoint of Product Development. It begins by looking at development theories, namely top down and bottom up and …

Establishing A Quantitative Foundation For Exactly Constrained Design, Alisha M. Hammond

Theses and Dissertations

Exactly constrained (EC) design is a robust design method which can be used for mechanical assemblies. It entails using the minimum number of constraints to eliminate all desired motion.

While found by some engineers in industry to have many benefits (including robust assembly, no binding or play, ease of assembly, and the ability to tolerate the wear of parts), EC designs remain somewhat unrecognized by academia. One reason for this minimal exposure may be the lack of a quantitative foundation for such designs. This thesis describes the history and current background for EC designs, and it also begins to develop …

Alternative Post-Treatment Processes In The Nasa Lunar-Mars Habitat, Sarah Yeldell

Honors Capstone Projects and Theses

No abstract provided.

Rotational Molding Of Acrylonitrile-Butadiene-Styrene Polymers And Blends, Mark Grant Spencer

Theses and Dissertations

The development of acrylonitrile-butadiene-styrene (ABS) resins for use in rotational molding would provide a medium performance material, thus opening doors to new markets for the rotational molding industry. Unfortunately, ABS resins have shown serious problems during the rotational molding process, namely discoloration, bridging, and poor impact strength. It is believed that these effects are due to degradation of the carbon-carbon double bond in the butadiene, through attack by either oxygen or heat. Previous efforts have shown some success in addressing these issues. However, additional improvements are necessary to make ABS resins commercially viable to rotational molders. This study, fourth in …

Satellite Scatterometers: Calibration Using A Ground Station And Statistical Measurement Theory, Peter Kenneth Yoho

Theses and Dissertations

Satellite scatterometers have recently gained popularity due to their unique ability to measure global geophysical data on a daily basis. Increased interest in scatterometry mandates improved design and calibration of these instruments. This dissertation presents new techniques for scatterometer calibration and addresses issues related to the design of future instruments and applications. First, the use of a calibration ground station is considered. A new methodology is established for calibration of SeaWinds, NASA's current scatterometer, using a receive-only ground station. Principles of the methodology are implemented, new analysis techniques developed, and important results obtained for instrument timing, frequency, power, position, and …

Adapting An Effective Interface For A Passive Solar System With A Truncated Pyramid Concentrator, Shirley M. Flinders

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Masters of Science by Shirley M. Flinders on December 3, 2003.

Prediction Interval Estimation Techniques For Empirical Modeling Strategies And Their Applications To Signal Validation Tasks, Brandon Peter Rasmussen

Doctoral Dissertations

The basis of this work was to evaluate both parametric and non-parametric empirical modeling strategies applied to signal validation or on-line monitoring tasks. On-line monitoring methods assess signal channel performance to aid in making instrument calibration decisions, enabling the use of condition-based calibration schedules. The three non-linear empirical modeling strategies studied were: artificial neural networks (ANN), neural network partial least squares (NNPLS), and local polynomial regression (LPR). These three types are the most common nonlinear models for applications to signal validation tasks. Of the class of local polynomials (for LPR), two were studied in this work: zero-order (kernel regression), and …

Analytical Modeling Of High Performance Reconfigurable Computers: Prediction And Analysis Of System Performance., Melissa C. Smith

Doctoral Dissertations

The use of a network of shared, heterogeneous workstations each harboring a Reconfigurable Computing (RC) system offers high performance users an inexpensive platform for a wide range of computationally demanding problems. However, effectively using the full potential of these systems can be challenging without the knowledge of the system’s performance characteristics. While some performance models exist for shared, heterogeneous workstations, none thus far account for the addition of Reconfigurable Computing systems. This dissertation develops and validates an analytic performance modeling methodology for a class of fork-join algorithms executing on a High Performance Reconfigurable Computing (HPRC) platform. The model includes the …

Monte Carlo Simulation Of Neutron Detectors, Andrew Curtis Stephan

Doctoral Dissertations

Neutron detectors are simulated using Monte Carlo methods in order to gain insight into how they work and optimize their performance. Simulated results for a Micromegas neutron beam monitor using a custom computer code are compared with published experimental data to verify the accuracy of the simulation. Different designs (e.g. neutron converter material, gas chamber width, gas pressure) are tested to assess their impact on detector performance. It is determined that a ¹⁰B converter foil and 1 mm drift gap width work best for a neutron beam monitor. The Micromegas neutron beam monitor neutronics are evaluated using the computer …

Numerical Simulation Of Separating Flows Using Computational Models Based On The Vorticity Confinement Method, Lesong Wang

Doctoral Dissertations

The objective of the present research is to investigate the recent development of the vorticity confinement method. First, a new formulation of the vorticity confinement term is studied. Advantages of the new formulation over the original one include the ability to conserve the momentum, and the ability to preserve the centroid motion of some flow properties such as the vorticity magnitude. Next, new difference schemes, which are simpler and more efficient than the old schemes, are discussed. At last, two computational models based on the vorticity confinement method are investigated. One of the models is devised to simulate inviscid flows …

Transportation Shortest Path Search Area Model, Hui Wang

Doctoral Dissertations

Although many studies on shortest-path algorithms have been conducted in the past, few of them have considered the time and effort required to obtain and update the weight property of the network arcs. For transportation-related problems – due to the size and complexity of the network – preparing, updating, and transmitting the network database on which the shortest-path algorithms perform can be a challenge.

This study designed a Transportation Shortest Path Search Area (TSPSA) model to enhance the database preparation and updating step before any shortest-path search algorithm can start processing. Taking advantage of the characteristics of the transportation networks, …

Thermography Detection On The Fatigue Damage, Bing Yang

Doctoral Dissertations

It has always been a great temptation in finding new methods to in-situ “watch” the material fatigue-damage processes so that in-time reparations will be possible, and failures or losses can be minimized to the maximum extent. Realizing that temperature patterns may serve as fingerprints for stress-strain behaviors of materials, a state-of-art infrared (IR) thermography camera has been used to “watch” the temperature evolutions of both crystalline and amorphous materials “cycle by cycle” during fatigue experiments in the current research.

The two-dimensional (2D) thermography technique records the surface-temperature evolutions of materials. Since all plastic deformations are related to heat dissipations, thermography …

Effects Of Environment And Frequency On The Fatigue Behavior Of The Spallation Neutron Source (Sns) Target Container Material - 316 Ln Stainless Steel, Hongbo Tian

Doctoral Dissertations

As the candidate target container material of the new Spallation Neutron Source (SNS) being designed and constructed at the Oak Ridge National Laboratory (ORNL), 316 low-carbon nitrogen-added (LN) stainless steel (SS) will operate in an aggressive environment, subjected to intense fluxes of high-energy protons and neutrons while exposed to liquid mercury. The SNS is an accelerator-based neutron source that provides pulsed beams of spallation neutrons by bombarding a mercury target with 1 GeV protons. The function of the SNS is to convert a short pulse (< 1 ms, 60 Hz, 17 kJ/pulse), high-average-power (1 MW), 1-GeV proton beam into 18 lower-energy (< 1eV), short-pulsed (~ tens of ms) neutron beams optimized for use by neutron-scattering instruments.

The current project is oriented toward materials studies regarding the effects of test environment …

Directional Solidification, Microstructures And Mechanical Properties Of Cr-Cr3si Eutectic Alloys, Hongbin Bei

Doctoral Dissertations

Alloys based on intermetallics have been considered for high temperature structural applications. However, many of these alloys suffer from intrinsic brittleness and low fracture toughness at ambient temperature. Therefore, ductile-phase-toughened intermetallic composites are being investigated as a means to improve the fracture toughness. A subset of this class of materials is in-situ composites produced by directional solidification of intermetallic eutectics. In this study, the Cr-Cr₃Si eutectic system is selected as a model system to investigate composites by directional solidification, where the strong, but brittle Cr₃Si is combined with a more ductile Cr-rich solid solution.

A series …

Integrated Field Emission Electron Guns With Single Vertically Aligned Carbon Nanofiber Cathodes, Michael Alberto Guillorn

Doctoral Dissertations

Nanostructured carbon-based materials hold great promise as field emission (FE) cathodes for integrated FE devices. These materials display remarkable FE properties as a consequence of their unique chemical and physical properties. Among this class of materials, the vertically aligned carbon nanofiber (VACNF) is exceptional in that its synthesis can be deterministically controlled. This has enabled the characterization of the FE properties of individual VACNF grown on Si substrates. The results of these studies indicate that the VACNF is an excellent candidate for integrated FE electron sources where the generation of a focused electron beam from a microscale structure is required. …

Design And Development Of A Lubrication Pump For A Horizontally Mounted Air-Conditioning Compressor., Kenneth T. Gilbert

Electronic Theses and Dissertations

Horizontally mounted compressors offer the advantage of reduced height in central air-conditioning units but prove difficult to produce economically due to costs associated with the manufacture of acceptable lubrication systems for the compressors. This study develops an effective, affordable oil pump for use on a horizontal compressor. Concepts are proven through testing of prototype assemblies. Test results drive modifications for future prototypes, and prototypes demonstrating adequate performance are modified for ease of manufacture.

Research in this study proves that the most suitable design results from a modification of a rotating vane pump. The pump’s modifications enable it to pump oil …

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.

Stream Water Quality Modeling In The Great Smoky Mountains National Park., Thomas Wayne Barnett

Masters Theses

The purpose of this study was to examine water quality in the acid-impacted Great Smoky Mountains National Park (GRSM). Water samples have been collected roughly quarterly at ninety sampling sites throughout the Park. These samples were analyzed for pH, acid neutralizing capacity (ANC), conductivity, major cations, and major anions. This thesis utilizes data from samples collected from October, 1993 to November, 2002.

The trout fisheries of the GRSM are considered some of the best in the eastern United States. However, fisheries biologists at the GRSM believe that some of the streams that once supported trout populations twenty or thirty years …

Comparison Of Microbial Cell Densities And Treatment Performance In Nitrifying Activated Sludge Reactors, Janalyn Rae Brown

Masters Theses

A thorough understanding of microbial dynamics in activated sludge treatment is currently unrealized due, in part, to quantitative techniques that rely on culture-dependent methods. The bias inherent with cultivation techniques may result in isolates that do not necessarily represent those dominant in the system evaluated. In situ analysis of microorganisms functioning in wastewater reactors will provide a greater understanding of how particular groups of organisms, such as nitrifiers, are impacted by system fluctuations. This information is vital for improved process design and control. The overall goal of this research was to investigate the use of the real-time polymerase chain reaction …

The Effects Of Temperature And Solids Retention Time On Activated Sludge Treatment Performance, Jack Mcclendon Carley

Masters Theses

A bench-scale treatment system with external clarifier was used to determine the effects of solids retention time (SRT) and temperature on treatment performance while simulating the full scale activated sludge process. Four bench-scale reactors, operating at SRTs of 20, 10, 5 and 2 days, were fed settled municipal wastewater collected after primary clarification from the Kuwahee wastewater treatment plant in Knoxville, TN. Three operational temperatures were investigated during this study, 22oC, 12oC and 7oC. The order and duration of operation at each temperature was first 22oC for 61 days, next 7oC for 47 days and lastly 12oC for 105 days. …

A Preliminary Study Of The Effects Of Exposure To A One Atmosphere Uniform Glow Discharge Plasma (Oaugdptm) On The Surface Energy And Strength Of Meltblown And Nanofiber Fabrics, Weiwei Chen

Masters Theses

Electrohydrodynamic (EHD) methods have recently been developed to electrospin nano-scale non-woven webs and to improve their properties by exposure to the One Atmosphere Uniform Glow Discharge Plasma (OAUGDPä), as a collaborative effort by the UT Plasma Sciences Laboratory and the UT Textiles and Nonwovens Development Center (TANDEC).

Nanofiber webs are made by the electrospinning (ES) process, which uses the electrostatic force to spin fibers from a polymer solution or melt. Digitized SEM images show that the fiber diameters range from 10 nm to several microns. Such nanofiber fabrics have a significantly higher tensile strength than meltblown (MB) webs of the …

Theoretical And Experimental Study Of Degradation Monitoring Of Steam Generators And Heat Exchangers, Xuedong Huang

Masters Theses

The objective of this research is focused on the modeling, analysis, and experimental study of steam generator and heat exchanger degradation monitoring and fault diagnosis. Experimental and analytical studies of tube fouling are performed and the system-level degradations are monitored using data-driven modeling of heat exchanger measurements. Initially, a comprehensive literature study was made on the steam generator and heat exchanger degradation types and mechanisms, including fouling and corrosion.

Based on the mass balance, energy balance, and momentum balance and the moving-boundary method, a multi-node SIMULINK model of a U-tube steam generator (UTSG) has been developed so as to simulate …

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, 2^nd-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 …

Limestone Contactors As A Corrosion Control Technology For Small Public Water Systems: An Educational Module For Drinking Water Professionals, Azarina Mohd Jalil

Masters Theses

This thesis includes a review of literature of the limestone contactors technology for small water systems and discusses the process and methodology involved in developing the educational module on limestone contactors. It includes most of the narrative texts presented in the module. Both this thesis and the module are intended to be used as an educational tool by small public water system operators, owners, regulators, and engineers of limestone contactors as a corrosion control method to meet the lead and copper action level stated in the U.S. EPA’s Lead and Copper Rule. This module includes the description of the processes …