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Nonlinear Robust Control Of A Series Dc Motor Utilizing The Recursive Design Approach, Michael J. Burridge

Retrospective Theses and Dissertations

In this thesis, the investigation of asymptotic stability of the series DC motor with unknown load-torque and unknown armature inductance is considered. The control technique of recursive, or backstepping, design is employed. Three cases are considered. In the first case, the system is assumed to be perfectly known. In the second case, the load torque is assumed to be unknown and a proportional-integral controller is developed to compensate for this unknown quantity. In the final case, it is assumed that two system parameters, load torque and armature inductance, are not known exactly, but vary from expected nominal values within a …

Calculating Cross Slot Flux Losses In High Voltage Stator Coils, John D. Amos

Retrospective Theses and Dissertations

At present there are several methods for calculating temperature for inner-cooled stator coils for large electric generators. Determining the highest temperature in a stator coil is very important and is a major limiting factor for the maximum capability of steam turbine synchronous generators.

The load current in the stator winding causes losses in the conductor resistance. That same current excites leakage fluxes that link contours inside the conductors causing non-uniform current distribution and additional losses. these additional losses are caused by eddy currents induced inside the stator coils. These eddy losses are grouped as radial flux losses, cross slot flux …

Gaussian Beam Resonator Formalism Using The Yy Method, Kenneth A. Menard

Retrospective Theses and Dissertations

A simple and powerful new paraxial ray formalism is shown to provide an alternate method for designing Gaussian Beam Resonators. The theory utilizes the Delano yybar diagram approach and is an extension of the recent work by Shack and Kessler for laser systems. The method is shown to be complementary to the conventional ABCD method and is founded upon J.A. Arnaud's pioneering ideas for complex rays. The thesis develops an analytic formulation of a ray based complex wavefront curvature and yields a clearly generalized description of spherical wave propagation, for which Gaussian beams are considered a special case. The resultant …

Effects Of Avian Breeding Colonies On A Man-Made Freshwater Marsh In East Central Florida, James L. Burney Jr

Retrospective Theses and Dissertations

The effects of nutrient loading from avian breeding colonies into aquatic/marine ecosystems have been well documented. Documented influences include increased productivity of aquatic/marine macrophytes, elevated sediment nutrient concentrations, and increased densities of zooplankton and planktivorus fishes. The primary pathway of nutrient export from the rookery is through excreta from adult birds and their offspring. This study examined the influences of a 400-nesting pair rookery of cattle egret (Bubulcus ibis) in 1990 and a 75-nesting pair rookery of cattle egret in 1991 on a man-made freshwater treatment marsh in east central Florida. Because the fundamental intent of the created marsh (study …

Finite Impulse Response Utilizing The Principles Of Superposition, Scott Edward Carter

Retrospective Theses and Dissertations

Window functions have been greatly utilized in the synthesis of finite impulse response (FIR) filters implemented using surface acoustic wave (SAW) devices. The critical parameter in any FIR design in the impulse response length, which must be optimized for the given design specifications in order to reduce the size of each device. To this end, many design algorithms have been introduced such as Remez exchange, linear programming, and least mean squares. A new algorithm has been derived which is efficient and accurate for the design of arbitrary filter specifications requiring less computations than the current algorithms. The FIR design is …

Experimenting With The Finite Element Method In The Calculation Of Radiosity Form Factors, Donna Marie Chesteen

Retrospective Theses and Dissertations

Radiosity has been used to create some of the most photorealistic computer-generated images to date. The problem, however, is that radiosity algorithms are so computationally and memory expensive that few applications can employ them successfully. Form factor calculation is the most costly part of the process. This report describes an algorithm for using the finite element method to reduce the amount of time that is used in the form factor calculation portion of the radiosity algorithm. This technique for form factor calculation significantly reduces the number of projections done at each iteration by using shape functions to determine the distribution …

Expression Patterns Of Developmental Genes In Drosophila Melanogaster Larval Genital Discs, Denise E. Freeland

Retrospective Theses and Dissertations

No abstract provided.

Development Of A Desuperheater Rating Method For Energy Code Calculations, Tim Merrigan

Retrospective Theses and Dissertations

The purpose of this project was to develop a rating method for desuperheater water heaters – heat exchangers that remove superheat from the refrigerant in an air conditioner’s compressor discharge line. The project methodology was to first determine the overall heat transfer coefficient-area product (UA) of the heat exchanger for three basic types of desuperheaters. Both heat transfer analysis and the laboratory performance data indicated that the number of transfer units (NTU) for each heat exchanger was relatively independent of the operating conditions for a properly-charged air conditioner with a single-speed compressor and a desuperheater with a single-speed circulating pump. …

Tender Offer Outcome Prediction Based Upon Efficient Market Hypothesis, James I. Montgomery

Retrospective Theses and Dissertations

A significant portion of firms' capital expenditures in the recent past have been accomplished through the acquisition of the assets of other firms by tender offers. While the majority of tender offers are successful, a significant number of tender offers fail for various reasons. The accurate prediction of the success or failure of a tender offer would provide investors with valuable information upon which to base their investment decisions. The target firm shareholders could use the information as a base for their tendering decision. For the abitrageur, a predictive model would reduce the uncertainty associated with their investment activity and, …

Shape Reconstruction From Shading Using Linear Approximation, Ping Sing Tsai

Retrospective Theses and Dissertations

Shape from shading (SFS) deals with the recovery of 3D shape from a single monocular image. This problem was formally introduced by Horn in the early 1970s. Since then it has received considerable attention, and several efforts have been made to improve the shape recovery. In this thesis, we present a fast SFS algorithm, which is a purely local method and is highly parallelizable. In our approach, we first use the discrete approximations for surface gradients, p and q, using finite differences, then linearize the reflectance function in depth, Z ( x , y), instead of p and q. This …

Reexamining Argumentativeness And Resistance To Persuasion, Matina Suzanne Vourvopoulos

Retrospective Theses and Dissertations

A recently developed receiver characteristic, argumentativeness, was examined for its relations to attitude change and information processing in persuasive communication. Generally thought to be a flowed personality trait, argumentativeness is currently being regarded in communication studies as a beneficial personality trait that correlates with other qualities such as high grade point average, dynamism in speech, achievement orientation, competitiveness and leadership behavior. This study examined the effect of argumentativeness on persuasion. It was predicted that high argumentative would be more resistant to persuasion, yet the findings show that, with a strong message, high argumentative are more likely to be persuaded by …

Behavior Of The Solutions To A Functional Equation Which Equates A Function's Inverse To Its Reciprocal, Robert Rudolph Anschuetz

Retrospective Theses and Dissertations

This thesis explores the behavior of solutions of the functional equation f-1(x)= 1/f(x) for x ε Dom(f), where f is a real-valued function of a real variable. It is quite common to mistake the notation f^-1, which means the inverse of f with respect to composition with the inverse of f with respect to multiplication, usually denoted by 1/f. This thesis shows that although f^-1 and 1/f are usually different function, they do indeed sometimes represent the same function. This thesis will also provide …