Engineering Commons^™

A Piezoelectric Actuated Scanning Mirror System Utilizing A Type One Control Loop, David Gibbs

Retrospective Theses and Dissertations

The purpose of this thesis is to design and build an improved control loop for a piezoelectric actuated scanning mirror system. A control system has been built having zero steady state position error and an 80 Hertz bandwidth. This was achieved by placing the piezoelectric actuator in the feedback path of an operational amplifier and placing series cascaded notch filters and lead compensators in the forward path of the control loop. A prototype system, including compensation and feedback, is developed. Its performance compares favorably with that of the system model. It is capable of plus and minus 1.7 degrees of …

Char: The Fire Investigators Aid The Implementation Of Expert System, Pamella M. Johnson

Retrospective Theses and Dissertations

The purpose of this research is to determine the applicability of expert systems to fire investigation. This will be accomplished by: a) using an expert systems building tool, b) extraction and organization of the knowledge base, c) application of the system to solve a real problem.

Barium Borate In Parametric Oscillation And 1.54 Micron Generation, Mark Kerrigan

Retrospective Theses and Dissertations

As to date, there are several relatively new crystals that have been developed for nonlinear or "parametric" optical applications, including KTP, LAP, KNbO3, m=NA, and BaB204 (barium borate, or simply BBO). The latter crystal, BBO, and the use of BBo to achieve parametric oscillation around an eyesafe wavelength of 1.54 microns is the emphasis of this paper.

Unpublished material includes determining the optimum type of coupling and pump wavelength used when generating 1.54 μm eyesafe radiation based upon Poynting vector walk off, suscpetibilityies, and both signal angular and spectral acceptance widths. Poynting vector walk off curves for linearly polarized extraordinary …

Uniform Energy Discharge For Pulsed Lasers, Eric Calvin Koschmann

Retrospective Theses and Dissertations

The art of achieving a large energy discharge in a controlled manner with relative ease is to use a pulse forming network. Historically the design of such networks generally used a single inductor and capacitor. Although easy to design and implement, this practice does not provide optimum performance in all cases. In particular, most laser welding requires a uniform energy discharge in a pulse to produce a high quality weld. Analysis has shown that when the pulse forming network approximates a lumped constant transmission line a maximum flat pulse is produced with minimal degradation of the pulse rise time. This …

Ada Real-Time Performance Benchmarks For Personal Computer Environments, Stephen L. Laroche

Retrospective Theses and Dissertations

A set of benchmarks were developed to test the real-time performance of Ada Personal Computer (PC) compilers. The benchmark set measures the overhead associated with various functions, including subprogram calls both from within and outside of packages ( including generic), dynamic allocation and deallocation of objects, exceptions, task activation/termination, task rendezvous, various time related functions, common arithmetic functions, and file I/0. The benchmark set also determines the type of memory deallocation supported, and determines whether fixed-interval or pre-emptive delay task scheduling is used. The different benchmarks are described along with an explanation of the testing methods for each benchmark. Two …

Three-Level Block Truncation Coding, Deborah Ann Lee

Retrospective Theses and Dissertations

Block Truncation Coding (BTC) techniques, to date, utilize a two-level image block code. This thesis presents and studies a new BTC method employing a three-level image coding technique. This new method is applied to actual image frames and compared with other well-known block truncation coding techniques.

The method separates an image into disjoint, rectangular regions of fixed size and finds the highest and lowest pixel values of each. Using these values, the image block pixel value range is calculated and divided into three equal sections. The individual image block pixels are then quantized according to the region into which their …

Design Of A Bandpass Oculometer, Karin Brandauer

Retrospective Theses and Dissertations

A passive oculometer is a device that measures the position of the eye by utilizing the corneo-retinal potential (CRP) generated by the eye. In this thesis, the Bandpass Oculometer replaces the joystick of a personal computer, allowing the viewer to use a computer simply by moving his eyes. Low frequency noise, present in all electronic circuits, produces an offset from the reference point, the center of the screen. In previous lowpass oculometry studies at University of Central Florida, this offset caused the cursor to drift toward the edge of the field of view within a period of 30 seconds, decreasing …

Computerized Data Acquisition In Experimental Applications, Jay A. Meyer

Retrospective Theses and Dissertations

This thesis project was intended to provide the University of Central Florida Mechanical Engineering and Aerospace Sciences Department with computerized data acquisition (CDA) capabilities. The data acquisition system has been designed for use in laboratory instruction and research experimentation. The development of the CDA system began in the spring of 1987. This development included the acquisition of system hardware and the design of software. The expertise required to carry out this project was obtained by many hours of laboratory experience. This experience was gained not only in university laboratories but also in international studies at the Euratom laboratory in Italy. …

Object-Oriented Development Techniques For Real-Time Software Systems: A Case Study, Thomas S. Seldenright

Retrospective Theses and Dissertations

Great improvements have been made in computer technology over the last forty years. Today, systems are being developed to solve complex problems that were previously thought to be out of the reach of computer solutions. Unfortunately, advances in software development techniques have been outpaced by the advances made in hardware development techniques. In recent years, effort has been made to formalize software development techniques suitable for real-time systems. This paper presents an object-oriented approach to realtime systems development. The object-oriented development approach is applied to a real-time case study problem. The case study involves controlling the speed of a toy …

Survey Of Local Area Networks For Low End Systems, Wipawadee P. Sonprasit

Retrospective Theses and Dissertations

Local area networks (LANs) that support small systems, the personal computers in particular, are surveyed. LAN environments, factors motivating interest in PC LANs, and capability requirements of LANs posed by low-end systems users, are outlined. Discussion of LAN technology includes standards, architecture, transmission media, topology, transmission techniques, access protocol, and performance factors topics. Commercial products are presented with more in-depth outline on selected products. Observation and future of PC LANs conclude the survey.

Design Of A Systolic Architecture To Implement Graphic Transforms, Aimee A. Murray

Retrospective Theses and Dissertations

The graphics generator hardware is an important component of flight-training simulators. The function of this hardware is to generate 3D perspective images at rates of 30 frames per second to produce realistic out-ofwindow scenes viewed by the crew under training. Within most graphics generator hardware are array processors which achieve high computation throughput necessary to generate real-time processing. The function of the array processors is to transform, clip, rotate and perspective project the data base into screen coordinates for use by the graphic generator. A FIMD (few instructions multiple data) systolic architecture is proposed to achieve high computational throughput that …

Computer Aided Design Of Linear Phase Finite Impulse Response Digital Filters, Wentao Lyou

Retrospective Theses and Dissertations

This research report is an investigation of techniques for designing linear phase finite-duration impulse response (FIR) filters. The software package, CADFIR, developed for this project can be used to design linear phase FIR digital filters via three well-known design techniques: the window method, the frequency sampling method, and the optimal filter design method. CADFIR has options for designing such standard filters as lowpass, highpass, bandpass, and bandstop filters as well as multipassband-stopband filters. The fundamental properties of FIR filters are discussed and design algorithms associated with the three FIR filter design techniques are developed. Design examples are included and the …

Dynamic Performance-Based Student Model For An Intelligent Simulation Training System, Jenifer M. Sargeant

Retrospective Theses and Dissertations

Student modeling has been the subject of research since the mid-1970's. A student model is an evolving description of what the student knows about the subject domain. Much of the previous research has concentrated on evaluating a student in performing cognitive tasks. The Intelligent Simulation Training System (ISTS) applies the techniques of Artificial Intelligence, Intelligent Tutoring Systems and Expert Systems to simulation-based training. The ISTS Student Model is unique in that it evaluates the student in performance-based tasks. It monitors and records the student's ability to maintain relationships between objects in space and time. The scope of this research was …

Efficient Algorithms For The Fixed Charge Problem, Ahmad Abdulah Moreb

Retrospective Theses and Dissertations

The main thrust of this research is to develop four solution procedures for the Fixed Charge Problem. All are based on approximating the fixed charge component by strictly polygonal linear components. The first procedure uses the functions technique to approximate the fixed charge; then linear programming with the restricted-basisentry technique is used to arrive at the final solution. Although this method starts with an approximated version of the fixed charge component, it arrives at an exact value to the objective function without the need for re-evaluating the objective function. The other three solution procedures are based on approximating the fixed …

A Comparison Of Two Microcomputer Continuous Simulation Languages, Amy Brannon Kirkland

Retrospective Theses and Dissertations

Until the early 1980s, most digital simulation models of reasonably complex systems required the use of a mainframe for a solution to be obtained in a timely manner. Recently, the declining prices of computer memory, operating systems, and modern hardware have supported the implementation of large simulation packages on smaller machines. Today, tremendous improvements in the performance of microcomputers have provided the simulationist with a completely personalized, less expensive computing environment. Operating within a microcomputer environment, the simulationist must choose a suitable computer language. Often, user familiarity dictates the selection of a language, while other factors such as ease of …

Comparison Of Graphical Design Methodologies, Pamela Stark Woodard

Retrospective Theses and Dissertations

The recent development of the Ada language by the Department of Defense and its required use within the Department of Defense for the development of embedded software systems has resulted in a need for better methods to represent Ada software designs. Graphical design techniques have long been used as software design and documentation aids. The use of graphical techniques to illustrate an Ada design can provide a clear, concise means to describe a complex software system. The purpose of this paper is to investigate several software design methodologies which incorporate graphical design notations. The specific software methodologies examined in detail …

The Feasibility Analysis Of Cooling A Residential Space Using An Underground Air Pipe Coupled With An Air Chimney, Nam Ky Trinh

Retrospective Theses and Dissertations

This study examines the thermal and economic feasibility of using an earth-cooled air system of residential space cooling. A residential building located in Orlando, Florida was modeled to determine the sensible cooling load for various design factors. A parametric study was conducted to determine the effects of the following: inside set temperature, infiltration rate, and overall heat transfer coefficient of the walls and roof. The inside set temperature had the greatest impact on the cooling energy load, followed by the infiltration rate and the overall heat transfer coefficient of the walls and roof.

Two load conditions were examined to determine …

High Resolution Monopulse Tracking, Larry Alan Young

Retrospective Theses and Dissertations

High Resolution Radar techniques are applied to the problem of resolving a multiple target array and locating its geometric center without the usual biasing toward the brightest targets. Monopulse radar techniques are combined with high resolution stepped frequency pulse train signal processing in an amplitude tracking radar.

A single pulse monopulse system's aimpoint is biased toward the brightest point targets in an array. However, by using a stepped frequency pulse monopulse radar, the cross range distance to each individual scattered may be found.

Unlike the single pulse monopulse system, the aimpoint is independent of the reflectivity of the targets. The …

Economic Design Of Lot-By-Lot Acceptance Sampling By Attributes, Michael S. Wall

Retrospective Theses and Dissertations

Risk-based sampling plans have long been the accepted standards in the practice of acceptance sampling for quality control. Usually the economic consequences of a given sampling plan are assessed by experience and intuition at best. With the availability of high speed computers and well-proven statistical methods, economically-optimal sampling pl a ns can now be developed so that much of the guesswork is removed. This study first surveys these methods for deriving economically-optimal sampling plans. Then, recognizing the reluctance in government and industry to abandoning ris k-based design of sampling plans, a method is explored which poses a compromise between the …

Utilizing Object-Oriented Design To Reduce The Effort Expended On The Maintenance Phase Of A Software Project, Susan Muriel Storma

Retrospective Theses and Dissertations

Due to poor software design, software products typically incur substantial cost overruns during the maintenance phase of the life cycle. Use of modern software engineering principles (e.g., information hiding and abstraction) can i mprove the design of a product and, hence, reduce the effort associated with the maintenance phase of a product. Object-oriented design (OOD) is a tool which embodies these software engineering principles. This paper first presents the concepts of 00D and how it is used. A design example involving a programmable temperature controller is presented utilizing 00D and is then compared to a top-down design approach. Conclusions are …

An Adaptive Multi-Scene Correlation Algorithm, Paul E. Vogt

Retrospective Theses and Dissertations

Digital scene matching algorithms have been used in both military and commercial image processing systems for years. The trend toward using multiple sensors in military imaging systems has generated anew interest in real time techniques to accomplish sensor fusion tasks such as field of view alignment. This thesis analyzes methods presently in use and introduces a novel algorithm that improves scene correlation performance. The focus of the new technique is in the segmentation area, where significant features are extracted from background and clutter. These performance improvements are especially helpful when the scene contains excessive noise and or lacks detail, a …

Numerical Analysis Of The Resonant States Of Quantum Wells And Superlattice Devices, Alan Gilbert Whittaker

Retrospective Theses and Dissertations

This thesis is concerned with the development of a numerical model to describe the resonant states associated with quantum well and superlattice devices. A numerical method is described where the time-independent Schrodinger equation is represented as a series of simultaneous algebraic equations using the finite-element method. The eigenvalues for these equations are then found using a Sturm sequence, and the eigenfunctions subsequently calculated using a reverse iteration method containing orthogonality constraints. Simulations of specific devices are presented and compared with experimental results and good correlation is observed.

Investigative Study Of The Reliability Of A Rotating Turbine Blade, William Stuart Beal

Retrospective Theses and Dissertations

-Turbine blading incidents are a concern to electrical utilities since they can result in power plant unavailability. The reliability of a particular turbine blade is investigated in this report to determine if it can be replaced with a more reliable blade design. The majority of incidents concerning this blade have been attributed to stall flutter vibration that has been the result of unit operation at low load levels with high back-pressures in the steam condenser. Stall flutter can be avoided by limiting back-pressure levels during low load operation and is thus not a concern here. Another potential cause of unreliability …

Investigation Of Surface And Subsurface Deformation In Sliding Wear, Patrick J. Mohr

Retrospective Theses and Dissertations

The research presented in this paper is part of the ongoing work by Moslehy and Rice et al. at the University of Central Florida in the investigation of sliding wear using laser techniques. This research paper investigates related wear phenomena, metallographically, and presents some general trends observed in the growth of the elastic - plastic interface as a function of time. Observations were made on the surface and at near surface sections on several brass pin specimens, each being subjected to sliding wear for various periods of time. Metallographic observation of the plastic deformation that occurred on the surface of …

An Overview Of Machine Vision, Juan C. Telchi

Retrospective Theses and Dissertations

The objective of this paper is to examine new ideas and other useful information on the most recent advances in the robotic vision field. A visual system model was introduced and the basic components of this model were explained. The principal areas in robotic vision were researched. This included two dimension and three dimension vision sensors. Industrial applications and future developments of machine vision systems were addressed. A survey was done to summarize the vision system market and the robot market share worldwide.

Finite Element Analysis Of A Glass Fiber Inclusion, Jeffery R. Southland

Retrospective Theses and Dissertations

This analysis investigates the micromechanical behavior of a fiber-reinforced composite. Two realistic deviations from the typical set of simplifying assumptions are considered: nonhomogeneous matrix properties and imperfect fiber/matrix bonds. The stress effects due to a soft matrix interlayer at the fiber interface and the loss of a portion of the fiber/matrix interface bond are examined. The analysis is performed with the ANSYS finite element program. The effects of higher order shape functions and different mesh densities are studied. The final results are compared to a previous analysis performed at Florida Technological University (now University of Central Florida) which utilized a …

Polar Spectrum Coding, Daniel Harris Chapman

Retrospective Theses and Dissertations

Polar Spectrum Coding is a novel speech coding algorithm for narrowband voice communications. A polar Fourier transform of the signal is computed, and the magnitude and phase of the speech spectrum is encoded for transmission. The correlation between frames of speech signals is exploited to minimize the transmission rate required for intelligible speech. At the receiver, the encoded words are decoded and the spectrum reconstructed. An inverse Fourier transform is performed, and the result is the reconstructed speech waveform. Polar Spectrum Coding theory is explained. The sensitivities of various parameters on performance are explored, and performance in the presence of …

Analysis Of Phase Noise In Phase Lock Loop, Diane Marie Pavik

Retrospective Theses and Dissertations

This research report presents an introduction into phase lock loops (PLL) with a major emphasis on calculating phase noise in frequency synthesizers. A PLL model that incorporates the major sources of noise is presented for the purpose of design analysis. The model can be used to analyze second and fifth order PLLs which allows the accurate calculation of phase noise as a function of independent variable design parameters. The stability of PLLs is also analyzed to show the effects of a marginally stable system on the resultant phase noise. Developing an accurate PLL model which accounts for the major sources …

Axisymmetric Wave Propagation In A Finite Linear Elastic Cylinder, Brian D. Johnson

Retrospective Theses and Dissertations

This work addresses the linear elastic analysis of axisymmetric wave propagation in a finite elastic cylinder. The waves are generated by the Fast Triaxial Device (FTRXD), which fails soil specimens at very rapid rates. The very short duration of the triaxial tests requires the consideration of wave phenomena in the analysis of the test results.

The soil specimens are modeled as linear elastic cylinders which are compressed in the axial direction. The resulting axisymmetric waves are analyzed with the wave equations which are cast in finite difference form, allowing the solution of displacements and stresses throughout the cylinder as a …

Continuous Time Convolution Model For Generation Synthetic Hydrographs, Cheryl Brooks

Retrospective Theses and Dissertations

Synthetic hydrographs are often used in stormwater management to provide estimates of peak rate, volume and time distribution of stormwater runoff. A hydrograph model based on the mathematical technique of convolution was developed using an exponential routing response function and the basic watershed continuity equation. After incorporating the model into a computer program, it was calibrated using hydrographs from four urban and three rural watersheds. The watersheds are located in regions of west and south Florida and range in size from 14.7 to 3500 acres. Two other hydrograph models, the Soil Conservation Service's Unit Hydrograph (SCS-UH) mode 1 and the …