Engineering Commons^™

Model For A Nonlinear Tank System Under Proportional-Integral-Derivative Control, Charles W. Bishop

Retrospective Theses and Dissertations

A model (NONLINRK) was developed for a closed tank system under feedback control by an ideal proportional-integral-derivative controller. Under servo action the fluid level in the tank is altered from its equilibrium set point. Under regulatory action the feed pressure to the inlet valve and/or the outlet valve percentage opening are varied from equilibrium settings. The numerical model uses Gill’s fourth-order Runge-Kutta algorithm to solve the system equation. The equation was made separable by approximating an exponential factor by the tangent at the beginning of each time step in the numerical solution. NONLINRK simulation trials exhibited many characteristics of linear …

A Computer Graphics Head-Up Display For Air-To-Air And Air-To-Ground Flight Simulation, Daryl R. Mair

Retrospective Theses and Dissertations

A computer graphics simulation of an aircraft Head-Up Display was designed using an RDS-3000 Ikonas Graphics Processor and a PDP-11/34 host computer system. The software control and display modules were accomplished using Ikonas microcode and Digital Equipment Corporation Fortran IV-PLUS. The Head-Up Display system consists of the basic flight data, which includes aerodynamic flight information, Roll/Pitch Ladder, and the Velocity Vector or Flight Path Marker. The system was designed for flexibility in modifications and evaluation of various weapons delivery systems. These will be adapted to specific needs by research scientists and engineers at the Visual Technology Research Simulator in Orlando, …

Design And Analysis Of A 4ghz Low Noise Amplifier, Abdulla I. Al-Rawahy

Retrospective Theses and Dissertations

The Gallium Arsenide Field Effect transistor (GaAs FET) is experiencing a widespread acceptance in space and terrestrial systems due to its low noise, high gain and frequency characteristics unmatched by bipolar devices. This paper describes a design of a 4 GHz low noise amplifier with GaAs FETs using the scattering parameters method. Special attention is given to overall noise/gain optimization in the band of interest. The Smith Chart is used extensively to match the two-port device with microstrip networks. Analysis and performance of the amplifier are presented.

Use Of The Ada Language System In Configuration Control Of Fortran-Based Software, Daniel L. Dyke

Retrospective Theses and Dissertations

The Configuration Control and Management of Trainer Systems Software has been recognized as a significant problem for many years. Many software tools are being developed for use as aids in this task. The efforts of the Department of Defense in the development of Ada and an Ada Programming Support Environment (APSE) have strongly addressed the problems of configuration control and management. However, these efforts have been targeted for Ada-based software as it is anticipated it will be the primary language of the DOD. The author feels that FORTRAN based software will require maintenance for many years even after the acceptance …

An Algorithm For Computing Fast, Accurate, Z-Plane Root Locus Plots, David R. Jahn

Retrospective Theses and Dissertations

Root locus analysis/synthesis is an extremely powerful tool used in classical control system design. Its results can be used to check stability, speed of response, and system damping. However, the solutions to root locus problems can be extremely difficult to obtain in digital control system because the poles are in close proximity. Optimized algorithms will be presented which circumvent this problem and allow for fast, accurate z-plane root locus plots. Prompting for data entry, minimum memory in-place computations, and very little processing requirements yield an easy to use, highly efficient program.

Design Considerations For A Digital Audio Equalizer, Timothy Young

Retrospective Theses and Dissertations

The objective of this thesis is to consider a method for designing a digital audio equalizer. The primary design criteria is minimum audible frequency response error between a digital and a "reference" analog equalizer throughout the entire audio frequency range from 20 Hz to 20 Khz. The first step is to obtain a set of analog filters that suitably represent the reference equalization. From these filters, digital filter coefficients are generated using the bilinear transformation. Then, the digital filters are combined with anti-aliasing and D/A reconstruction filters and a zero-order hold to complete the design. Analysis of methods to minimize …

Digital Signal Processing Capabilities Of The Fujitsu Mb8764, Harold B. Creech

Retrospective Theses and Dissertations

The Fujitsu MB8764 digital signal processing chip is designed to operate with a machine cycle of up to 10 MHz. The chip’s ability to perform a 16-by-16 bit multiply and add operation in one machine cycle makes it a good candidate for real time digital signal processing. Unlike the Intel 2920 the Fujitsu MB8764 does not have an onboard analog-to-digital, digital-to-analog converter. Therefore, this paper will be restricted to the operation of this device with digital data input and output. The use of the MB8764 as a digital filter is analyzed. Performance limitations due to finite word length, memory size …

Computerized Displacement Data Analysis In Laser Speckle Photography, Bijan Chitsaz

Retrospective Theses and Dissertations

Laser speckle photography is an experimental technique which provides a non-contract means for direct measurement of in-plane displacements of objects subjected to different loading conditions. It requires a camera system to record two images of the object that are illuminated with laser light on a high resolution film. The double-exposure film (specklegram) is a permanent record of the displacement information of the object. Point-by-point analysis of the specklegram will yield the displacement data, but requires considerable time to complete the data reduction. An automated data analysis system is developed and described in this report. He-Ne laser and computer-controlled translation stages …

A Computational Model To Estimate The Thickness Of The Waterfilm Due To Rain On The Upper Surface Of An Airfoil, Padmanabha R. Chappidi

Retrospective Theses and Dissertations

Based on a two-phase boundary layer approach, a computational model is proposed to estimate the thickness of the waterfilm due to rain on the upper surface of an airfoil. The coupling between the air boundary layer and the water film is established by the conservation of mass and momentum at the interface. By a simple coordinate transformation, the interface is conformed to the finite difference grid system. Trajectory analysis of a raindrop of 1 mm diameter shows that the impingement of drops is high near the leading edge of the airfoil and decreases downstream. The finite difference equations of air/waterfilm …

Interfacing A Quadriplegic To A Computer Using The Electro-Ocumeter, Paul J. Godfrey

Retrospective Theses and Dissertations

The purpose of this is to design an electro-oculometer system that paper will enable quadriplegics and other persons with severe physical disablities to use a computer. An electro-oculometer is a device that measures the position of a person's eyes. The vertical and horizontal movements of the eyes can be used to control an object on a computer screen. This, in turn, allows the user to operate a computer by eye motion alone. The requirements of the electro-oculometer system are specified and then a block diagram of the system is developed. Each block is then designed and component values are given. …

Phase Statistics For A Lightwave Traveling Through Turbulent Media, Donald J. Link

Retrospective Theses and Dissertations

A probability density function is developed for the phase of light that is the result of adding a signal to noise with K-distributed amplitude and uniform phase. The probability density function of the phase associated with the I-K distribution is also developed. In the process of deriving the probability density function of the phase much I as learned about the relationships between different probability density functions. Three different methods of deriving homodyned K statistics are shown to be equivalent. Two different methods of deriving I-K statistics are shown to be equivalent. Theoretical moments of the homodyned K distribution are compared …

Proposals For Energy Conservation Measures For A Specific Small Business, Scott W. Snapp

Retrospective Theses and Dissertations

A case study into energy conservation measures for a specific building has been made. Primary emphasis is directed towards conserving energy necessary for heating the building. Once the building outlay and the scope of energy usage trends are established, different conservation actions are considered. Extensive measurements and observations on the building were made to gather data on areas, materials, thicknesses, and means of heating the building. The goal of such action was to compare the magnitude of heat loss from different sections of the building. With this information it can be understood where to insulate, and the significance of air …

Survey Of Texture And Shading Techniques For Visual Flight Simulation, Walter R. Steiner

Retrospective Theses and Dissertations

Shading and texturing are two techniques that flight simulators can take advantage of to increase scene realism. Shading imitates the effects of light reflecting from a surface. Texture refers to superimposing a pattern on a surface to give the illusion of extra detail and realism.

In this report, several techniques for shading and texturing are evaluated with respect to their applicability to visual flight simulators.

The image quality produced by shading and texturing is a function of computation cost. The Phong model is found to produce the most realistic shading, but is too computationally expensive. The Gouraud shading model improves …

Stability Of Steel Structures, Abbas K. Hosseini

Retrospective Theses and Dissertations

In the design of an elastic structure, a major consideration is the overall stability of the system under axial load or a combination of an axial load and bending moment. In first-order analysis the effects of axial forces on the stiffness formulation and their influence on deformations of the members are usually neglected. If the axial forces are sufficiently large, a better indication of the distribution of the forces and moments in the structure is obtained by using a second-order analysis. In this type of analysis the moment equilibrium equations are based on the deformed shape of the structure. The …

Experimental Software Package For Linear Programming, Deborah S. Fogal

Retrospective Theses and Dissertations

A software package for linear programming has been developed using the revised simplex and dual simplex algorithms. The design of the program incorporates an experimental change in the dual simplex algorithm. If the entered problem is not primal feasible, a modified dual simplex algorithm is used. The traditional dual simplex method requires an initial dual feasible basis and maintains feasibility throughout its application. The experimental change is to ignore this criteria of dual feasibility. The objective then becomes to obtain primal feasibility. Once this is attained, the revised simplex algorithm is applied to obtain optimality, if this has not been …

Evaluation Of A Binary Spatial Light Modulator Correlator Using Time-Domain Polarity Coincidence Correlation Theory, Thomas J. Posluszny

Retrospective Theses and Dissertations

Time-domain Polarity Coincidence Correlators (PCC) have been studied for the possible extension of these theories to the spatial-domain in the context of an optical PCC. The existing body of knowledge has been found to be inadequate for direct application to the spatial-domain. However, by remodeling the type of clipper or hardlimiter used in the development of the existing theory from a signum (bipolar) clipper to a binary (unipolar) clipper, a new expression for the output signal-to-noise ratio of an optical PCC is developed. This modification is necessary to account for the unipolar nature of light intensity. Both the existing time-domain …

Experimental Investigation Of Campbell Pacific Nuclear Corporation Mc-1 Density-Moisture Nuclear Gauge On Sand, Clay, Asphaltic Concrete And Concrete, Carl H. Francois

Retrospective Theses and Dissertations

The time-consuming traditional methods of determining soil density and moisture content have been widely replaced by more advanced techniques using radioactive isotopes such as cesium, americium, and beryllium. To ensure the validity and accuracy of the results from a nuclear gauge unit designed by Campbell Pacific Nuclear Corporation, a conventional standard test, the sand cone replacement method, was used in tandem with the nuclear instrument for the density and moisture content determination in sand and clay at different sites. The results of the two methods of measurement agree within close limits. An empirical equation was derived to correlate the data …

Analysis And Modification Of An Electro-Oculometer, Munir. Ahmed

Retrospective Theses and Dissertations

This paper describes an electro-oculometer and analyzes the electronic circuits required to process the signal. This electro-oculometer is a passive, two-channel device which detects the eye orientation using commercially available electrodes attached near the eyes. The electro-oculometer is composed of a special amplifier followed by a parabolic filter. The amplifier has high common mode rejection ratio, low drift, and low input bias current. Both DC and AC analyses of the electro-oculometer have been performed. The common mode rejection ratio (CMRR) of the input stage of the device is computed both at low and high frequencies. The experimental data were then …

Infiltration Through Roadside Swales, Eduardo. Avellaneda

Retrospective Theses and Dissertations

In recent years, there have been efforts to develop a design procedure for swale systems which could be applied to permeable soils. This design should consider space limitations or any other site restriction. Five existing swale sites in the Central Florida area were instrumented to determine flow rates and permeability’s. Twenty-two experiments were performed. It is concluded that the use of a double-ring infiltrometer to determine the infiltration rate is possible for existing swale sites. Another conclusion is that published values of permeability are very variable and accurate, nor specific enough to predict actual infiltration rates. However, very conservative values …

Multiplan Models For Construction, Edson. Jackson

Retrospective Theses and Dissertations

As computer hardware becomes smaller and increasingly less expensive, more contractors can now use computers to do a number of construction computations which were formally done on hand calculators. The advent of user-oriented software packages has had a significant impact on the traditional data processing procedures of the construction industry. Among the software packages that are available for a large number of computer systems are electronic spreadsheets. Electronic spreadsheets packages, such as Multiplan, are widely used where the display of information can best be depicted in an array of rows and columns. It is frequently useful in situations in which …

Internal Precision And The Common Sample Rate, James C. Kirkwood

Retrospective Theses and Dissertations

The relationship between internal precision and input/output precision and the ratio of sample frequency to signal frequency has been described in qualitative terms for the general case and in quantitative terms for many special cases. This paper attempts to generate quantitative approximated guidelines for the general case. Lowpass and bandpass digital filters are implemented using cascaded second order sections via a program that varies the amount of internal precision available for the emulation, and calculates the error produced compared to a 64 bit standard. The errors are plotted, and general equations relating input/output precision and internal precision and the ratio …

Speciation Of Heavy Metals In Highway Drainage Systems, Lee P. Wiseman

Retrospective Theses and Dissertations

A trace metal speciation scheme proposed by Batley and Florence (1976) was applied to determine the physiochemical forms of zinc, cadmium, lead, and copper in two Central Florida highway drainage systems. The linearity and limitations of the ASV technique were also examined. The measurements showed that (a) more than 70% of the soluble Zn and Cd in all of the waters analyzed existed as liable ionic metal (b) lead was divided between labile and non-labile inorganic forms, but one particular form, PbCO₃, predominated (c) a substantial fraction of copper is associated with organic colloids if humic substances are …

Suitability Of The Tms320 Digital Signal Processor In Digital Signal Processing Applications Requiring Multiple-Precision, Randall L. Walker

Retrospective Theses and Dissertations

The TMS320 single-chip digital signal processor, produced by Texas Instruments, shows promise for a long life-cycle not only because it fills a technical need in the digital signal processing field; but because it also represents an excellent early design. Furthermore, Texas Instruments has provided thorough software and development support. However, this chip was not designed to support digital signal processing applications which require multiple-precision operations. In this paper, algorithms were developed and expressed in macros that provide the capability of modeling systems requiring multiple-precision operations. Finally, a performance envelope showing the system complexity versus sampling bandwidth limitations is provided to …

Exfiltration From Stormwater Ponds In Central Florida, Nicolas E. Andreyev

Retrospective Theses and Dissertations

The objective of this study is to develop guidelines for the analysis of storm water retention ponds in Central Florida. Development of a combined seepage analysis considering both unsaturated and saturated groundwater flow incorporation into a systematic approach for storm water retention pond design will result in safer and more economical storm water management practices. The research was conducted in four phases: 1) A literature review. 2) A review of mathematical and empirical analysis of transient – unsaturated/saturated groundwater flow. 3) Construction and testing of a downscaled storm water pond model. 4) Incorporation of full scale percolation pond test data …

A Comparison Of Analog And Direct Digital Control (Ddc) Of A Physical Process, Clifton R. Hargrove

Retrospective Theses and Dissertations

The following report presents the development of a computer-based system designed to examine the response of a physical process is a process trainer, PT326, from Feedback Corporation. There are two main categories of control available to the user: (1) analog control and (2) digital control. Within each of these categories the following types of control systems are available: (1) Proportional control, (2) Proportional-Integral control, (3) Proportional-Integral-Derivative control and (4) On-Off control. The user can examine both regulator and servo response for any of the given control systems. All parameters associated with the selected control system are variable and user-input. The …

A Projectile Subsystem In A Flight Simulation System, Robert F. Hodson

Retrospective Theses and Dissertations

An overview of a flight simulation system is presented with a discussion of the system components and the interaction between functional units. The functions of each unit in the visual system are described. Specifically, the projectile subsystem portion of the visual system is presented in detail. A projectile subsystem executive structure is presented with capability of controlling projectile activation and deletion. Mathematical models for missiles with linear projected impact and proportional guidance are discussed. Ballistic projectile models with and without wind and drag considerations are developed. The mathematical equations for position and attitude calculations are given. Design considerations and implementation …

An Approach To Noise Estimation And Elimination In Communication Systems, Jerome J. Viviano

Retrospective Theses and Dissertations

This paper is a description of the analysis and testing of a method to estimate noise mixed in with a desired signal and to then subtract out the estimated noise. The paper documents the situation in which noise becomes a problem, the method of noise elimination, the mathematics used to analyze the noise eliminator, a digital/analog hybrid simulation of a system utilizing the techniques described, and comparative results between expected performance and actual system performance. Also described is the practicality of the system, the limitations of the system and its unique capabilities. Since the system is a totally new concept, …

Golden Opportunities For White Collar Productivity Improvements In Quality Assurance, Jane M. Algee

Retrospective Theses and Dissertations

The efficient processing of defective or nonconforming hardware and paperwork is important to both defense contractors and the government. Management's concern of excessive costs in this area initiated an investigation into the actual activities, personnel, and computer systems involved in such processing. Applicable military specifications and an assortment of corporate and divisional procedures were reviewed to obtain baseline data. Additional information was sought through personal interviews and visits to the manufacturing areas. The activity flow was documented in block diagrams and time estimates and labor requirements were applied. The detailed labor estimates were input to a LOTUS123 spreadsheet and used …

Optimization Analysis For Alignment Criteria And Installation Of Gravity Flow Underground Pipe, Eugene N. Balter

Retrospective Theses and Dissertations

In 1982 the Business Roundtable prepared several reports which investigated various aspects of construction which posed significant research opportunities. Their findings placed piping construction in the group of activities categorized as having "highest potential" for improvements based on inefficiency, or construction difficulty and proportionate costs. It was estimated that over $1 billion could be saved annually if the difficulty in the piping industry was improved to only average of other areas. Further investigation into the piping area showed that the alignment process took 20% of the cycle time for installation and ranked either first or second as compared to other …

A High Level Programming Language And Graphics Simulator For The Heathkit Et-18 Hero Robot, Kenneth J. Sizemore

Retrospective Theses and Dissertations

As modern industrial robots are used more in industry, the need for qualified programmers and operators will increase. Inexpensive robots are available for use as training systems, but these robots typically lack the high level tools, such as high level, languages and graphics simulators, that are available for the industrial robots. A high level programming language and a graphics simulator were developed for one of these training robots, the Heath ET-18 Hero Robot. The programs were designed to be executed on an IBM Personal Computer. The software was developed as part of an overall system which also includes a compiler …