Engineering Commons^™

The Optimized Electrostatic Motor, Christopher Lee Rambin

Doctoral Dissertations

The most common means of electrically activated actuation is the electromagnetic motor. All electromagnetic motors have a low output to weight ratio and low energy efficiency. The motor's weight is due to the coils and magnets used to generate propulsion. The energy loss is mainly the result of Joule heating that is inherent with any current driven device. An electrostatic motor offers the potential of significantly less weight and higher energy efficiency. This lower weight characteristic is due to the epoxide material used to construct the major components of its propulsion unit. Greater efficiency results from the reduced Joule heating …

Fuzzy Logic Applied To System Control To Enhance Commercial Appliance Performance, Glenn Moffett

Doctoral Dissertations

The purpose of this research is to determine the usefulness of fuzzy logic and fuzzy control when applied to a commercial appliance. Fuzzy logic is a structured, model-free estimator that approximates a function through linguistic input/output associations. Fuzzy rule-based systems apply these methods to solve many types of "real-world" problems, especially where a system is difficult to model, is controlled by a human operator or expert, or where ambiguity or vagueness is common.

This dissertation presents fuzzy sets, fuzzy systems, and fuzzy control, with an example conveying the use of fuzzy control of a consumer product and an overview of …

Chemical Kinetics And Heat Transfer In Polyurethane Foam And Resin Composites, Yumi Morisaki

Master's Theses - Daytona Beach

A development of the composite materials parts require knowledge of the theoretical model that describes the physics, the chemical kinetics, and the heat-transfer properties of the materials.

For this work, the chemical kinetics of the polyurethane foam and the fiberglass-reinforced resin is investigated individually. An adiabatic method, which is commonly used by many investigators, is used for the polyurethane foam, while an isothermal degree and the rate of cure relationship is applied for the resin. A heat transfer effect during the curing process of both polyurethane foam and the resin is also investigated. A common approximate method for the heat-conduction …

The Cluster Multipole Algorithm For Far-Field Computations, Rakesh R. Patel

Electrical & Computer Engineering Theses & Dissertations

Computer simulations of N-body systems are beneficial to study the overall behavior of a number of physical systems in fields such as astrophysics, molecular dynamics, and computational fluid dynamics. A new approach for computer simulations of N-body systems is proposed in this research. The new algorithm is called the Cluster Multipole Algorithm (CMA). The goals of the new algorithm are to improve the applicability to non-point sources and to provide more control on the accuracy over current algorithms. The algorithm is targeted to applications that do not require rebuilding the data structure about the system every time step due to …

Meta-Ethnographic Development Of A Dialogue Methodology Applied To Organization Discourse, Shelley P. Gallup

Engineering Management & Systems Engineering Theses & Dissertations

A gap exists between theoretical stances that acknowledge the importance of dialogue as a dynamic within socially constructed structures, and "steersmanship" of those constructs--e.g., directing, intervening or transforming organizations. A "mechanism" which links theory with practice is missing, leaving practitioners with an acknowledgment of dialogue's central position, but without tools to enact this centrality in practice or research. This research constructs a conceptual model of dialogue, derived from the literature. Using this model as a base, the research seeks to generate a dialogue methodology bridging theory and practice with respect to organizational dialogue. The model, methodology, and research results are …

Consortia As Technology Innovation Management Vehicles: Toward A Framework For Success In Venture Based Public-Private Partnerships, Ralph B. Saunders Ii

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research was to explore the approach by federal/state agencies, university, and private sector consortia to develop and manage commercialization of innovation technologies. The evaluation, support, and management of technologically based consortia has traditionally been held in the private sector. There is a somewhat mature literature guiding innovation management (Utterback 1996; Rosenberg et al. 1994; Quinn 1997, 1992) in the private sector. However, there is an increasing emergence of consortia consisting of universities, industrial/private sector entities, and government agencies joining in collaborative efforts to launch technology based initiatives. These consortia are non-traditional and the applicability of traditional …

Effect Of Pulsed Electric Fields On Aquatic Nuisance Species, Amr Abou-Ghazala

Electrical & Computer Engineering Theses & Dissertations

Clinical and theoretical evidence indicate that electric fields have biological effects ranging from recoverable disturbance to mortality induction depending on the field parameters and time of exposure. In this thesis, the effect of electrical field in pulsed form on aquatic nuisance species is investigated. Pulse parameters in terms of amplitude, width, shape, and repetition rate that stimulate the species to desirable levels are to be defined. Applying the electrical pulses with appropriate parameters to stun aquatic nuisance species entering marine cooling systems will prevent it from attaching to pipe walls. The use of electrical fields to seek efficient, environmentally friendly, …

Microhollow Cathode Discharge Excimer Lamps, Ahmed El-Habachi

Electrical & Computer Engineering Theses & Dissertations

Microhollow cathode discharges are non-thermal discharges of such small sizes that thermalization of the electrons is prevented. By reducing the diameter of the cathode opening in these discharge geometries to values on the order of 100 $\mu$m we were able to operate discharges in argon and xenon in a direct current mode up to atmospheric pressure. The large concentration of high electrons, in combination with high pressures favors three body processes such as excimer formation. This was confirmed by experiments in xenon and argon where emission of excimer radiation at 172 nm and 130 nm, respectively, was observed when the …

An Injection Modelocked Titanium-Sapphire Laser, James C. Hovater

Electrical & Computer Engineering Theses & Dissertations

I have investigated the possibility of using an injection modelocked Ti-sapphire laser as a illumination source for GaAs photocathodes. A commercial Ti-sapphire laser was modified to accept a seed pulse from a gain-switched diode laser. Modelocked operation was obtained through gain modulation within the Ti-sapphire crystal as a result of injection seeding with a modelocked pulse train from a gain-switched diode laser. The Ti-sapphire laser essentially becomes a pulse amplifier for the diode laser. Unlike conventional modelocked lasers, the pulse repetition rate of this laser can be discretely varied by setting the seed laser repetition rate equal to multiples of …

High Pressure Radio-Frequency Microhollow Cathode Discharges, Anja Annett Muller

Electrical & Computer Engineering Theses & Dissertations

A new field of microhollow cathode discharges is represented by the RF microhollow cathode discharge. So far, the behavior and related physical processes of the RF microhollow cathode discharge are not well investigated.

RF microhollow discharges in air at high pressures were investigated under different experimental conditions. The geometry was changed by reducing the cathode hole diameter and the dielectric spacer thickness. By adding a noble gas to air, the influence of additive gases was explored. Additionally, the parallel operation of RF microhollow discharges was investigated.

It was shown that stable RF microhollow cathode discharges could only be sustained up …

Electrical Characteristics And Parallel Operation Of Microhollow Cathode Discharges, Wenhui Shi

Electrical & Computer Engineering Theses & Dissertations

This thesis describes the electrical properties of microhollow cathode discharges with argon as filling gas. The appearance and current-voltage characteristics of microhollow cathode discharges have been recorded. Three kinds of discharge modes (predischarge, hollow cathode discharge and abnormal discharge) have been observed. The range of operation of the hollow cathode discharge has been found to be 0.5 < pD & 5 Torr cm in argon. By reducing the hole diameter to 100 pm, we were able to operate the discharge to atmospheric pressure in a dc mode. The possibility of dc parallel operation of microhollow cathode discharges was explored. Parallel operation could be obtained without individual ballast for discharges with a positive I-V slope greater than 10 V/mA over a voltage range of more than 5 % of the sustaining voltage. For parallel operation outside the range the ballasting is required. This model was explored by using a segmented anode model. The result of the simple calculation coincides well with the experiment result, where a semi-insulator silicon was used as distributed ballast.

Shoreline Change Modeling As A Tool In Coastal Environmental Management, Jorge Espinoza Amaguana

Civil & Environmental Engineering Theses & Dissertations

The one-line numerical model GENESIS has been calibrated to evaluate its performance as a tool in providing insights into the physical components to manage the coastal environment. To calibrate the model, physical environmental data, literature research, and computer modeling methodologies were utilized in addressing the objectives of this thesis. The model was applied at three beaches of the Virginia Beach City with different man-made structures by using the actual field wave data for wave year J 997. Waves are the main environmental component affecting the coastal system; however, additional environmental data and the best engineering decision were used as model …

Experimental Analysis And Analytical Modeling Of Bridges With And Without Diaphragms, James J. Griffin, Issam E. Harik, David L. Allen

Kentucky Transportation Center Research Report

Two prestressed concrete (P/C) I-girder bridges along the coal haul route system of Southeastern Kentucky were constructed with a 50 degree skew angle. One of the bridges has concrete intermediate diaphragms, while the other bridge has no intermediate diaphragms. Bridges of similar design along coal haul routes have experienced unusual concrete spalling at the interface of the diaphragms and the bottom flange of the girders. The purpose of this report is to identify the cause of the damage, and to evaluate the effectiveness of intermediate diaphragms.

Experimental static and dynamic field testing was conducted on both bridges. All field tests …

A Methodology For Evaluating Large Truck Access To Intermodal And Other Facilities, Lisa Aultman-Hall, Michael Hill, Kenneth R. Agent

Kentucky Transportation Center Research Report

In a recent project for the Kentucky Transportation Cabinet (KYTC), researchers were tasked with developing a method to objectively evaluate the access for large trucks between intermodal or other truck traffic generating sites and the National Highway System (NHS). The routes evaluated were the actual roadway segments used by large volumes of trucks traveling between the intermodal or other facilities and the NHS. This choice to evaluate specific heavily used roadway segments, as opposed to evaluating an entire highway or roadway corridor was based on the recommendation of the state-wide Intermodal Advisory Panel which advised the Cabinet on intermodal issues. …

The Effect Of Peer Tutoring On The Test Scores Of Washington High School 9th Through 12th Grade Students Enrolled In Metals/Small Engines Class, Larry D. Harken

Graduate Research Papers

The purpose of this study was to investigate the effect of peer tutoring on the class-average tests scores of Metals/Small Engines students in grades 9-12 at Washington High School, Vinton, Iowa.

Experimental Investigations Of Wavelength And Angular Errors In Holographic Gratings With Non-Bragg-Matched Read Beams, Monish Ranjan Chatterjee, Vivek Ray

Electrical and Computer Engineering Faculty Publications

Perfect Bragg matching is generally desirable for accurate optical interconnections with holographic gratings. In reality, however, gratings may be illuminated by READ beams with non-Bragg-matched angles, or wavelengths, or both. In such cases, the scattered beams are generally misdirected, and may suffer loss of efficiency and possibly more serious errors such as crosstalk noise or missed connections. A conventional wave-vector triad method of analyzing the scattered beam errors leads readily to near-Bragg estimates of the output angular misalignment. However, the READ wave-vector triads appear to indicate a possible wavelength shift in the output beam even with a Bragg-matched READ wavelength, …

Comparison Of Observed And Simulated Grow-Finish Swine Performance Under Summer Conditions, Larry W. Turner, Thomas C. Bridges, Richard D. Coffey, Richard S. Gates, Gary R. Parker, Tami M. Brown-Brandl, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

As a part of a National Pork Producers Council educational program, our research and extension team at the University of Kentucky was linked with an independent commercial swine producer to test the NCPIG model against observed commercial on-farm data. This experience provided improved information for model development as well as increased producer insight into the data input needs and potential benefits of modeling. Detailed production information comparisons between the NCPIG model and producer data are presented for summer time conditions to assess the validity of the NCPIG model for simulation of grow-finish swine performance. Results demonstrated that the NCPIG model …

Quality Of Runoff From Plots Treated With Municipal Sludge And Horse Bedding, Elizabeth L. Busheé, Dwayne R. Edwards, Philip A. Moore Jr.

Biosystems and Agricultural Engineering Faculty Publications

Land application of horse stall bedding and municipal sludge can increase runoff concentrations of nutrients, organic matter, and bacteria as well as steroidal hormones such as estrogen. Concentrations of materials in runoff from sites treated with animal manure can be reduced by aluminum sulfate, or alum [Al₂(SO₄)₃•14H₂O] treatment. The objectives of this study were to assess plots treated with horse stall bedding or municipal sludge for: (a) runoff quality [concentrations of nitrate nitrogen (NO₃-N), ammonia nitrogen (NH₃-N), orthophosphate-phosphorus (PO₄-P), fecal coliform (FC), chemical oxygen demand (COD) …

Aggregate Production Planning In A Stochastic Environment, Ashraf Samy Naguib

Archived Theses and Dissertations

No abstract provided.

Effectiveness Of An On-Line Graduate Engineering Management Course: A Preliminary Study, Rosemarie Maffei Evans, Madison Daily, Susan L. Murray

Engineering Management and Systems Engineering Faculty Research & Creative Works

In the summer of 1997, the University of Missouri-Rolla's (UMR) Engineering Management Department began offering its first completely Web-based course. This graduate level course, Advanced Production Management, was designed to utilize a combination of Web-based tools to create a conducive, yet non-traditional, learning environment for its students. The students in the course did not physically have to attend any lectures and only met for an initial and final class period. The remainder of the course was conducted exclusively via Web-based tools. Accordingly, the Engineering Management Department commenced a research effort to determine the effectiveness of this new learning environment. This …

A Mentoring Guide For Female Faculty In Engineering, Susan L. Murray, Linda M. Manning, Catherine A. Riordan, Elizabeth Cummins, Philip B. Thompson

Engineering Management and Systems Engineering Faculty Research & Creative Works

One widely accepted method for increasing the chances of success of female engineering and science students and faculty alike is to provide access to female role models and mentors. In this article we offer to new female faculty, and to those who would mentor them, an annotated list of text and electronic resources that address most of the most important challenges facing new female faculty in science and engineering.

A Technology Assessment Survey For Web Based Higher Education Programs, Earl A. Evans, Susan L. Murray

Engineering Management and Systems Engineering Faculty Research & Creative Works

Advances in communications and computer technology, as well as in human-computer interfaces, have enabled concurrent advances in Web-based education. A number of case studies concerning applications of Web-based education for both distance learning and on-campus programs have been published. Primarily, these studies have focused on individual assessments of the web-based technologies. In contrast, this paper will provide a broad based assessment of applied web-based technology for higher education. This research was conducted via a survey completed by university and college faculty from numerous 4-year institutions. To gain an effective assessment, eleven categories of web-based course delivery tools, such as chatrooms …

Multiple Streams Synchronization In Collaborative Multimedia Systems, Emilia Stoica

Computer Science Theses & Dissertations

With the recent increase of the communication bandwidth and processor power, new types of applications have emerged. Among them, there are multimedia application, in which users are able to control, combine, and manipulate different types of media, such as text, sound, video, computer graphics, and animation. A key requirement in any multimedia application is to synchronize the delivery of various media streams to the user. To achieve this, the sender has to provide the temporal relations between the streams as they are captured. Since the receiver uses this information in streams presentation, its accuracy is very important.

Our main contribution …

Nonlinear Stability And Control Of Three-Dimensional Boundary Layers, Erik Janke

Mechanical & Aerospace Engineering Theses & Dissertations

The linear and nonlinear evolution of steady and traveling disturbances in three-dimensional incompressible boundary layer flows is studied using Parabolized Stability Equations (PSE). Extensive primary stability analyses for the model problems of Swept Hiemenz flow and the DLR Transition experiment on a swept flat plate are performed first. Second, and building upon these results, detailed secondary instability studies based on both the classical Floquet Theory and a novel approach that uses the nonlinear PSE are conducted. The investigations reveal a connection of unstable secondary eigenvalues to both the linear eigenvalue spectrum of the undisturbed mean flow and the continuous spectrum, …

Coupled Electrodynamic-Monte Carlo Simulations Of Nanoscale Gaas Terahertz Optical Mixers, Jiang Li

Electrical & Computer Engineering Theses & Dissertations

The concept of mixing or heterodyning has traditionally been used for microwaves and for radio frequency communications. However, the concept can easily be extended into the optical frequency regime. By doing so, the photomixing process can serve as a very versatile tool for both the generation of ultrahigh frequency (terahertz) and the detection of weak optical signals.

The aim of this thesis is to perform a theoretical study of the photomixing process inside GaAs devices as the non-linear elements. A coupled approach which combines the Monte Carlo simulation scheme for the carrier transport, with Maxwell's equation for the electrodynamics, has …

Bs News

Building Services Engineering

No abstract provided.

In Situ Infrared And Visible-Light Ellipsometric Investigations Of Boron Nitride Thin Films At Elevated Temperatures, E. Franke, Mathias Schubert, J.-D. Hecht, H. Neumann, T. E. Tiwald, Daniel W. Thompson, H. Yao, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

In situ infrared (IR) spectroscopy and visible-light (VIS) spectroscopic ellipsometry over the spectral range from 700 to 2000 cm^-1 and 1.5–3.5 eV, respectively, were used to investigate the optical behavior of boron nitride (BN) thin films at temperatures from room temperature (RT) to 600 °C. The polycrystalline hexagonal (h) and mixed-phase h- and cubic (c)-BN thin films were deposited by magnetron sputtering on [001] silicon. We observe a reversible moisture incorporation process in as-grown h-BN samples. When stored in normal ambient, the h-BN thin films absorb water into thin-film micropores. When annealed in ultrahigh vacuum or a …

Runoff And Erosion Following Field Application Of Beef Cattle Manure And Compost, John E. Gilley, Bahman Eghball

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Manure or compost from beef cattle feedlots can be excellent sources of nutrients and organic matter when added to soils. This study was conducted to determine the effect of a single application of manure and compost on runoff and erosion under no-till and tillage conditions. Tillage consisted of a single disking operation up and down the slope on a Sharpsburg soil which was cropped to grain sorghum or wheat the previous season. Manure and compost were applied at rates required to meet corn fertility requirements. Additional experimental treatments included the application of inorganic fertilizer and an untreated check. The addition …

Sustaina Bility Of Irrigation Schemes For Small-Scale Farmers: A Case Study Of Irrigation Scheme At Buleya Malima, Gwembe Valley, Zambia, Masinja R

Tanzania Journal of Engineering and Technology (TJET)

A study to determine facrors influencing sustainability of smallholder irrigation schemes was carried our a! Buleya Malima, Southern Province, 7_nnzbia. These factors included technical and socio-economic factors. found Out that the technical factors were 26.5, 64.5 and 9.2 percent for application efficiency, tailwater ratio and deep percolation, respectively, indicating that farmers wasted water mainly through tailwater runoff.From socio-economic point of view, the study indicated that the scheme lacked (i) farmer participation in designing and planning operation of the scheme (ii) managerial ability and innovativeness to form their own viable organisation: and (iii) formal training in technical operations of irrigation, infrastructure …

Successive Galerkin Approximations To The Nonlinear Optimal Control Of An Underwater Robotic Vehicle, Timothy Mclain, Randal W. Beard

Faculty Publications

The application of a new nonlinear optimal control strategy to the station-keeping control of an underwater robotic vehicle is considered. The control approach described and demonstrated here is based upon the numerical approximation of solutions to the Hamilton-Jacobi-Bellman equation. These solutions are computed by an iterative application of Galerkin's method. Preliminary simulation results demonstrating the application of this approach to the control of an underwater vehicle in the horizontal plane are presented.