Digital Commons Network^™

A Study Of Fmfb Demodulator Operation In The Presence Of Radio Frequency Interference And Gaussian Noise, Terry D. Wormington

Masters Theses

"A digital computer model of an FMFB demodulator has been used to study the effects of radio frequency interference on the detection of a sinusoidally modulated carrier. The effectiveness of selecting the feedback factor to suppress the interference for three values of modulation index is investigated. Also, the required IF bandwidth for the minimization of the mean-square error of the loop output between a signal corrupted by interference and the same signal without interference was investigated. More work is required before the effects of Gaussian noise plus interference on loop operation can be ascertained"--Abstract, page ii.

Data Compression Design Considerations For Airborne Test Vehicles, Kenneth Carlyle Pittman

Masters Theses

"The design goals for a data compression system are developed using previous studies as a cornerstone. Sampling theory is touched on with qualitative coverage of its effects. Consideration is given to various methods of data compression with the advantages and disadvantages of each noted. The requirement for buffering is discussed along with various methods that may be employed to achieve specific buffering goals. The impact of data reconstruction and how it may affect the choice of compression techniques is briefly covered. Selected compression algorithms and ways of increasing system effectiveness through alterations to their basic structures are described in detail. …

A Hardware And Software Interface Between A Magnetic Tape Unit And A Nova Mini-Computer, Thomas Dean Steury

Masters Theses

"This thesis is concerned with the general operation of the Kennedy Model 1400R incremental write/continuous read magnetic tape unit and the hardware design and software implementation needed to make it compatible for use with the Data General Nova 800 mini-computer.

The hardware design was developed around a General Purpose Interface Board which provides a standard set of logic needed for interfacing any external device to the Nova. The hardware consists of decode networks, mode selection networks, and I/0 timing networks. Special circuits needed to implement the hardware design and perform voltage conversions between the tape unit and the Nova computer …

Decimal-Base Binary Logic (Dbbl) Adders And Registers, James Oliver Bondi

Masters Theses

"This paper discusses a new type of base n adder and storage register. This new type of logic is called "n-base binary logic", or NBBL. The NBBL system is compared and contrasted with the Post base n system (a type of n-valued logic), the binary-coded base n system, and the straight binary system. The main purpose of this paper is to show that a decimal, or base 10, system can have some important inherent advantages over a binary system, such as greater daily operational efficiency. Furthermore, it is shown that a "decimal-base binary logic" system, or DBBL system, has inherent …

Experimental Study Of Neutron Reflection From A Cylindrical Surface, Dale Lee Holtzscher

Masters Theses

"The reflection patterns for an elliptical neutron beam impinging upon cylindrical and planar surfaces were measured. The flux intensity as a function of distance from the surface of either planar or cylindrical reflectors decreased monotonously with distance. No "focusing" of the neutron beam appeared in the case of the cylindrical reflectors but the flux did not decrease as rapidly as in the planar case. For the elliptical neutron beam the experimentally determined neutron flux distribution agrees with calculation"--Abstract, page ii.

Computerized Registration For High Schools, Kenneth Lee Fore

Masters Theses

"The guidance personnel in a high school are often burdened with the duty of hand scheduling the student's courses. Using the computer as a sub-optimizing tool in the registration of students, however, can cut scheduling time dramatically and relieve the guidance department of an onerous chore. The technique described in this investigation uses a conflict matrix that schedules the student's request and keeps the class load level within the course sections. A search of the schedule array for each course request may uncover a conflict. If no conflict occurs the course is scheduled and the remaining courses for this student …

Design Of A Torsional Vibration Machine, Prafulchandra Pragjibhai Desai

Masters Theses

"In this thesis the design of the major components of a torsional vibration machine is presented. The machine is a torsional vibration actuator which will deliver a mean output angular velocity with a superimposed harmonic component. This type of motion can be used to study the torsional vibration characteristics of models representing crankshafts, gear trains, torsional dampers, and other systems. The primary machine elements of the actuator are a power source, flywheel, and a Hooke's joint. The power source consists of a D.C. shunt motor and a drive transmission using 3 V-belts. Through the use of a Hooke's joint, approximate …

Calculation Of Buildup Factors For Multilayer Slab Shields Using The Monte Carlo Method, John Paul Kuspa

Masters Theses

"Gamma-ray beams normally incident upon slab shields of varying compositions are studied using a computer program based upon the Monte Carlo technique. Initial gamma energies of 1, 4, 6, and 8 MeV are considered. The shielding materials used were aluminum, iron, and lead. Both single and double material shields were investigated, at a variety of thicknesses up to a maximum of five mean free paths. Two secondary gamma processes are included in this simulation: annihilation gammas from pair production and bremsstrahlung from the electrons. The primary effort is the calculation of the dose, energy, and number buildup factors for these …

The Effects Of Intense Sound Levels And Steady Flow On The Propagation Of Plane-Waves In Air, Wuu Hao

Masters Theses

"This thesis is a theoretical investigation of the effects of intense sound levels and steady flow on the propagation of plane-waves in tubes of constant diameter. The analysis is limited to a study of the change of wave profile due to the intense sound levels, and steady flow. However, corrections for effects of viscous and heat conduction losses at tube walls are also presented. To simplify the analysis, the problem is treated by considering the steady flow and finite-amplitude-sound wave effects separately. For finite-amplitude sound only, two approaches are evaluated. The first uses small perturbations to derive a finite-amplitude wave …

A Comparison Of Analytical And Experimental Approaches In Determining The Thermoelastic Stresses Around A Cylindrical Inclusion Of Elliptical Cross-Section, Kenneth Byron Oster

Masters Theses

"Three approaches are used to determine the principal stress differences in an infinite elastic medium containing a cylindrical inclusion of elliptic cross-section due to a uniform temperature change. First, the two-dimensional equations of thermoelasticity are solved resulting in equations for the stress components anywhere in the medium material. Second, boundary displacements based on stress-strain relations are used as input displacements in a finite element program of the medium. Third, these same boundary displacements are used as input displacements on a photoelastic model simulating the medium. The problem is treated as one of plane strain in the first approach and one …

A Study Of The System Lithia - Silica, Roy Richard Ramey

Masters Theses

"X-ray intensity and d-spacing measurements were performed upon samples in the system Li₂O-SiO₂. Samples ranged from 0.0 to 28.0 mole percent lithia and were fired for 72 hours at temperatures from 920ºC to 1400ºC. Atomic absorption analyses were made upon the fired samples. Non-equilibrium conditions were prevalent and results are inclusive. Quartz is the stable phase in the high silica field at temperatures below 1050ºC with cristobalite stable above that. The quartz - cristobalite transformation occurs at 950ºC with the cristobalite transforming into tridymite at 1010ºC. There was wide scattering of data at 1000ºC and below. There was no correlation …

Transient Cooling Of A Sphere Due To Boiling, Salil K. Banerjee

Masters Theses

"The time - dependent surface temperature is determined for a sphere subjected to cooling by boiling. One dimensional heat transfer is considered and the solid is assumed to be homogeneous, isotropic and opaque to thermal radiation and to have temperature independent physical properties. The initial temperature of the sphere and the coolant are assumed to be uniform and arbitrary. The boiling heat transfer coefficient at the surface of a sphere is a strong function of the surface temperature thus resulting in an extremely nonlinear transient heat conduction problem. As a practical application of the problem, the process of quenching has …

Adsorption And Desorption Of Chlorinated Hydrocarbon Pesticides By Organic Humic Sludge, Fu-Sheng Chien

Masters Theses

"This research study was undertaken to investigate the fundamental sorption and desorption of selected organic pesticides by organic humic acids under laboratory-controlled conditions. Emphasis was placed on the evaluation of both the rate and the equilibrium of adsorption and desorption. Two types of chlorinated hydrocarbon pesticides were employed in this study. These are dieldrin and heptachlor, both of which are commonly used in today's agricultural applications. The adsorbent of organic humic acids was extracted from a coal-like substance called "leonardite," which has a humus content as high as 53 percent by weight. The experimental work of this study was conducted …

Application Of Transmission Matrices To Describe Transverse Vibrations Of Non-Uniform Bernoulli-Euler Beams, Dean Irle Parker

Masters Theses

"This report investigates the application of transmission Matrices to determine natural frequencies of non-uniform Bernoulli-Euler beams. The classes of non-uniform beams considered includes: truncated wedges, truncated cones, and truncated rectangular pyramids. Two transmission matrices were derived from solutions to the Bernoulli-Euler equation. One was an exact closed form solution which was applicable for the above classes of beams excluding uniform and nearly uniform beams. The second solution was an approximate one limited to the use for nearly uniform beams, but which does give the correct solution to the uniform beam in the limiting case. The transmission matrix has two advantages: …

A Study On The Lateral Placement Of Automobiles Due To Restrictions On Two-Lane Rural Highways, Warren Chip Woods

Masters Theses

"The driver of an isolated vehicle on a given section of highway, whether it is urban or rural, will choose a path on the pavement that offers the least resistance to driver effort and which to him seems safest. Lateral obstructions, such as retaining walls, trees, bridge abutments, ect., which may cause him to deviate from the desired path represent some degree of hazard to the driver and should be removed, if practicle. The purpose of this investigation was to determine any change in the lateral placement of automobiles due to side restrictions on rural two-way, two-lane highways. Phase one …

Analysis Of A Substitute For The Impact Damper To Damp Near-Resonant Mechanical Vibrations, Nguyen Khanh Van

Masters Theses

"This report investigates a substitute for the impact damper which, although highly effective in reducing vibration amplitudes of near-resonant mechanical systems, in operation causes often unacceptable intensive noise. The present damper consists of a piston free to move in a cylinder, at either end of which is a ball valve set to open at a preset pressure, and in the middle along its length an intake port. An approximate analytical study is made to determine the conditions for the existence of "noiseless periodic operation" of the damper, periodic operation without the occurence of impacts. This approach is based on the …

Phase Transformations In The System Zro₂-Cao, Damri Sukhotanang

Masters Theses

"Thermal expansion, thermal hysteresis, and the monoclinic tetragonal phase transformation of ZrO₂ have been studied with high temperature x-ray diffractometry. The initial transformation temperature in pure ZrO₂, on heating, is about 1150ºC. The transformation occurs over a 100ºC temperature range and thermal hysteresis occurs on heating and cooling. The mechanism of the transformation is related to preferred vibrational modes of atoms on the A_O -C_O plane of the monoclinic structure. Because the monoclinic B_O axis is parallel with the tetragonal [110] axis, structural relationships can be seen to be a controlling factor in the transformation. Initiation of …

The Steady-State Response Of A Fluid-Filled Beam Near Resonance, Niranjan Jayantibhai Patel

Masters Theses

"In this report the steady-state near-resonant vibration of a hollow fluid-filled beam is considered. The energy dissipation caused by the beam-fluid interaction is approximated by introducing a viscous damping force into the Bernoulli-Euler beam equation. A theoretical expression is developed for the displacement of the hollow beam by solving this modified Bernoulli-Euler beam equation. Tests are made using a cantilevered fluid-filled box to simulate a unit of beam-fluid length. The band-width technique is used to determine the incremental viscous damping coefficient from test data. A variety of fluids are used in the box to determine the effect of the fluid …

The Electric Field Strength Dependence Of Neutron-Induced Defects In Silicon P-N Junctions, Paul Edward Johnson

Masters Theses

"The effect of high electric field strengths (10⁴ to 10⁵ V/cm) present during neutron radiation on the neutron-induced defects is determined by utilizing the high electric field strength inherent in the emitter-base transistion region of an n-p-n transistor. A method is presented for the separation of neutron and gamma effects. Previous theoretical work on the ratio of base current increase to collector current decrease is applied to experimental data. The variations of the space-charge region volume damage introduction rate with neutron fluence and the average electric field strength are determined experimentally in order to obtain a measure of this effect. …

Wind Tunnel Modeling Of The Atmospheric Boundary Layer, Sreemanth Pagadala

Masters Theses

"The importance of simulating atmospheric flows in wind tunnels has been well established. Experiments were conducted in the Modified Aerodynamic Wind Tunnel to determine the suitability of this wind tunnel for simulating atmospheric flows and the degree to which various aspects of modeling could be fulfilled. A temperature profile to simulate the inversion aloft was generated inside the test section, and then an appropriate velocity profile was built in by means of screen mesh arrangements. The turbulence characteristics of the flow were measured. The validity of the temperature, velocity and turbulence fields were examined. It was found that while the …

A Practical Approach To The Exhaust Silencing Of A Pneumatic Rock Drill, Morton Gary Barth

Masters Theses

"One-third octave spectrum analyses of the exhaust noise produced by a medium sized pneumatic rock drill were obtained during free recriprocation to determine the most troublesome bands of noise. Noise reduction techniques were then used to design exhaust mufflers which would reduce the level of the exhaust noise to an acceptable level with a minimum increase in back pressure. The prototype mufflers evaluated included an expansion chamber, a resonator, and various modified expansion chambers. One of the modified expansion chambers tested provided very good attenuation reducing the exhaust noise from 113 dBA to 87 dBA at the operator's ear position. …

Use Of Glass Separated From Municipal Refuse In Asphaltic Concrete, Thomas Eugene Keith

Masters Theses

"The recent interest in municipal refuse recycling has brought about the development of several systems for separation of the refuse into components. One of the components reclaimed is a glass-rich fraction which, although primarily glass, contains various non-glass materials which the system is not able to remove. Clean waste glass can be used as an asphaltic concrete aggregate, and it would be desirable to use this glass-rich fraction in a similar manner. However, the effect, if any, of the non-glass components on the properties of an asphaltic mixture must be determined in order to utilize the glass-rich fraction with a …

An Investigation Of Stage I Fatigue Crack Growth In Fcc, Bcc, And Hcp Metals, Marion Anthony Russo

Masters Theses

"The objectives of this investigation were to 1) determine if Stage I mode or fatigue crack growth could be extended beyond the 45 degree maximum shear plane in metals having a face-centered, body-centered and hexagonal close pack crystal structure; 2) identify the crystallographic planes or crack propagation in Stage I growth in each crystal structure; 3) characterize the fracture surface topography or Stage I growth in each crystal structure. The test material used for this investigation consisted of alpha brass (70% Cu, 30% Zn), Armco iron and commercially pure titanium which are representative of FCC, BCC, and HCP crystal structures …

A Tensi-Volumetric Apparatus: Theory, Calibration, And Use In An Investigation Of The Oxygen Non-Stoichiometry Of Pure Batio₃, Glenn Jon Conger

Masters Theses

"The development of the tensi-volumetric apparatus has been traced to its current position of significance in studies relating to oxide non-stoichiometry. Components of the tensi-volumetric apparatus, especially the capacitance membrane manometer, were examined in detail as were the parameters affecting the performance of such an apparatus. Based on a careful consideration of components and performance, a tensi-volumetric apparatus has been designed, built, and its operation theoretically justified for its particular physical configuration. Results of existing studies of the oxygen non-stoichiometry of barium titanate have been used to predict its behavior during a tensi-volumetric study. Specific analytical procedures developed for use …

Design And Preliminary Testing Of A Rotary Internal Combustion Engine, Frank Darrell Statkus

Masters Theses

"With the advent of legislation against pollution, and rising wage, manufacturing, and materials costs, the prime mover industry is presently intent on developing new economical, non-polluting methods of power. It was the hope of the author that the engine described herein would provide an advancement towards meeting the new requirements. The design and resulting prototype is an eight cylinder rotary internal combustion engine, weighing approximately sixty pounds, and operating on the tour stroke principle. Theoretical calculations were made to determine ideal horsepower, mean effective pressure, and efficiency. Ideal horsepower ranged from 38.7 to 62.8. A dynamic analysis of the pistons …

Managerial Appraisals - A Systems View, James Thomas Hatlan

Masters Theses

"In the past decade much has been written concerning the performance appraisal which can be defined as the systematic analysis of the individual with respect to his performance on the job. The appraisal's importance lies in the fact that its impact is felt in the areas of control, promotion, and managerial development all of which are essential for the progressive firm. This study is an attempt to offer something new and something different. The author offers a systematic study of industry in general with specific help from key corporations and utilities. His investigations encompass the three elements of appraising and …

Experimental Studies Of Supporting Wire Disturbances In The Near Viscous Wakes Of Slender Supersonic Bodies, Kenneth Anthony Mirly

Masters Theses

"Wires have often been used as a means of mechanically supporting a model so that its wake will be relatively free of support interference. Such support systems have many advantages over stings and are less costly than magnetic suspension systems. Investigations into the disturbances caused by these supporting wires have been carried out with the use of a two-dimensional flat plate and a wire supported slender cone. The tests were conducted in the University of Missouri-Rolla axisymmetric, supersonic wind tunnel at Mach 3.15, and at a Reynolds number of 2.14 X 10⁶ per inch. Schlieren photography, pitot and static pressure …

Preliminary Studies With A Variable Transfer Composite Polymer Membrane., Samuel Walter Dortch

Masters Theses

"A preliminary study was done to determine the feasibility of using a compressed fibrous teflon (PTFE) silicone polymer membrane in extracorporeal oxygenation devices. A series of composite membranes were fabricated, using different concentrations of a dimethyl silicone polymer dissolved in petroleum ether, to give membranes having variable oxygen transfer properties. A gas-gas system was chosen to obtain the necessary transfer data. Data were obtained by transferring pure oxygen through the membranes into a mixture of 47 mole percent oxygen and 53 mole percent carbon dioxide. All analyses were obtained by chromatographic techniques. The results of these experiments show that membranes …

An Experimental Study Of Power Systems, Nguyen Quang Duoc

Masters Theses

"For three phase AC power systems consisting of synchronous machines interconnected by transmission lines and other electrical transmission equipment, the power transmitted and the stability of the system depend upon the constants of synchronous machine and the characteristics of the transmission lines. The purpose of this work is to design and set up a model of a power system in the laboratory, measure the constants of synchronous machines, the power angles and power flows of the system. An investigation of the effects of the saturated machines is based upon the laboratory data.

This work is intended primarily as a tool …

El Drama De Antonio Buero Vallejo: Implicaciones De La Desviacion, La Estigmatizacion, La Normalidad Y Los Valores, Mary F. Smith

Masters Theses

No abstract provided.