Digital Commons Network^™

A Laboratory Investigation Of Trace Metal Adsorption On A Marine Sediment In Sea Water And The Speciation Of Copper In Sea Water, David Allan Stern

Doctoral Dissertations

No abstract provided.

The Preparation, Characterization And Agricultural Use Of Bark-Sewage Compost, Raymond Henry Walke

Doctoral Dissertations

No abstract provided.

Stationary And Nonstationary Random Vibrations Of Cables, Plates And Beams With An Application To Ocean Structures, Frank Philip Alberti Jr.

Doctoral Dissertations

No abstract provided.

Social Feedback Processes Of The New Hampshire Mental Health Centers, Priscilla Sue Reinertsen

Doctoral Dissertations

No abstract provided.

The Design And Development Of An Ocean Sediment Probe, Edward Robert Kolbe

Doctoral Dissertations

No abstract provided.

An Interactive Computer Analysis Of Phonocardiograms, Antal Andras Sarkady

Doctoral Dissertations

No abstract provided.

The Preparation And Reactions Of 3,3-Disubstituted Thietanes And Their Derivatives, Maris Buza

Doctoral Dissertations

No abstract provided.

Wave Propagation In Viscoelastic Media, Gary Kenneth Stewart

Doctoral Dissertations

No abstract provided.

Characterization Of Heat-Treated Nickel And Gold Films On Silicon Single Crystals, Ki Hyun Yoon

Doctoral Dissertations

"An experimental electron impact ionization source was used to determine the presence of various neutral atoms and molecules on metallized and bare surfaces of silicon wafers. The metallization consisted of thin films of nicke l and gold separately and in combination. The major surface contaminates on all samples were found to be F, Na, Cl, K, CO, and CO₂. The surface concentration of these species was found to be sensitive to the sample temperature up to 550 °C, the maximum temperature used in this study.

In the course of the mass spectrometric study, it was found that crystallites …

Application Of Laser Holographic Interferometry To The Analysis Of Ground Movement Above Underground Openings, Duk-Won Park

Doctoral Dissertations

"A laser holographic interferometric technique has been recently developed and applied to research in several engineering fields. The technique has many possible applications in earth science and engineering. In this study it was shown that laser holographic ii interferometry can be used to study surface ground movements resulting from subsurface cavity collapse.

One of the most important advantages of the holographic interferometric technique is a rapid three-dimensional displacement measurement of a surface without contact or emplacement of instruments. The surface does not have to be flat or smooth allowing deflection contours to be generated on a granular surface. applied in …

Application Of Voltammetry To Copper Electrodeposition, Louis Francis Toth Jr.

Doctoral Dissertations

"A study was undertaken to determine the feasibility of using voltammetry and scanning electron microscopy techniques to characterize copper deposition from an acid-sulfate electrolyte. The main process variables investigated were temperature and addition agents (chloride ion, glue, separan or thiourea) at different concentrations, over a range of current densities. Cathodes employed were either polycrystalline titanium or copper. Some long-time copper deposits were also made using Ti cathodes and the orientations of these deposits were determined by x-ray diffraction.

Observations of copper crystals produced during voltammetry scans, on a Ti cathode, indicated that a characteristic morphology was associated with each type …

Development Of Helicopter Flight Path Models Utilizing Modern Control Techniques, Alfred Fermelia

Doctoral Dissertations

"The nonlinear set of equations which represents helicopter motion are linearized about a prescribed nominal state. Once the linearized system is obtained it is validated by comparing the output of the nonlinear system to that of its linearized counterpart. Having obtained a linear model, linear system theory may then be applied in order to investigate the stability and control characteristics of the aircraft.

General techniques for simulating helicopter pilot response for inclusion in a flight path simulation program have been devised. To provide the desired flight goal, a nominal flight trajectory is obtained from an existing nonlinear model. With this …

Use Of Adaptive Linear Equalization And Maximum-Likelihood Sequence Estimation In Conjunction With Filtering To Improve Qpsk Communication In Intersymbol And Interchannel Interference Channels, Srinivasa H. R. Raghavan

Doctoral Dissertations

"At high data rates, bandwidth is more constraining than transmitting power. Twice the data can be transmitted in a given bandwidth by using quadrature phase-shift keyed (QPSK) modulation schemes as opposed to biphase phase-shift keyed (PSK) systems, with a corresponding factor of two increase in power required for identical bit-error-rate performance. At high data rates intersymbol interference due to media dispersion degrades receiver performance . Other degradation results from interchannel interference, co-channel interference and noise may also be present in typical situations.

Equalization is a technique by which the receiver performance in the presence of intersyrnbol interference can be improved. …

Excitation Of Source Electromagnetic Waves At Microwave Frequencies Using Optical Techniques, M. Davarpanah

Doctoral Dissertations

"The coupling efficiencies for the excitation of surface electromagnetic waves (SEW} for both the prism and the grating techniques have been studied experimentally in the microwave frequency range. The grating experiments included studies of the SEW coupling efficiencies as functions of the frequency, the angle of incidence, the grating constant, the number of grating bars, and the position of the grating bar at which the maximum radiation field of the antenna was aimed. For the prism coupling technique, the coupling efficiency was studied as functions of the angle of incidence, the aiming point of the transmitting antenna on the prism …

Influence Of Initial Turbulence Intensity On The Heat And Moisture Transfer Through A Recirculated Air Curtain, Nguyen Quang Van

Doctoral Dissertations

"An air curtain is a directed jet of air separating a controlled space from an environment of different temperature and humidity. This investigation describes the development and verification of an eddy viscosity model which accounts for the influence of the initial turbulence intensity on the transfer of heat and moisture across a recirculated air curtain. The control of the turbulence intensity at the nozzle exit of an air curtain permits control of heat and moisture transfer and therefore the energy required to operate the air curtain.

Both theoretical and experimental studies were made of the recirculated air curtain. An explicit …

Effect Of Photoneutrons On Transients Of Beryllium Reflected Reactors, Safdar Ahmad Ali

Doctoral Dissertations

"An analytical model is developed to account for the photoneutron sources present in a beryllium reflector. The time-dependent, two- dimensional and three energy-group diffusion equations are written with an additional photoneutron source term. Then an approximate flux composed of two spatial shapes chosen beforehand, each having an unknown time coefficient, is inserted into time-dependent multigroup equations and the weighted residual criterion is applied. This yielded multimode kinetics equations with generalized definitions for conventional matrix parameters: generation time, reactivity, delayed neutron and delayed photoneutron fraction matrices.

Two transients are analyzed for the University of Missouri Research Reactor: simulation of rod drop …

Design, Fabrication, And Application Of Uniformly Distributed Rc Networks For Use In Electronic Circuits, Michael Flynn Kavanaugh

Doctoral Dissertations

"In the design of electronic circuits, both linear and non-linear, one of the goals is the reduction of the number of elements needed to complete the design. By using distributed RC networks a reduction in the number of elements by at least 50% is usually possible. This dissertation discusses several distributed RC networks, develops detailed design procedures for each, and applies them in the design of electronic circuits.

The indefinite admittance matrix (IAM) for the DRURC (double-resistive uniformly distributed RC network) and the URC (single-resistive uniformly distributed RC network) , which have been previously derived, are used as the starting …

Corrosion And Electrochemical Behavior Of Indium And Indium-Bismuth Alloys In Hydrochloric Acid, Yar Ming Wang

Doctoral Dissertations

"The corrosion of In-Bi alloys was studied using X-ray, scanning electron microscopy, atomic absorption spectroscopy, and cyclic voltammetry techniques.

Calculated activation energy values indicated that the corrosion of In-Bi alloys was activation controlled. The effect of amine mixtures on the corrosion of In and In₂Bi (ß₁ phase) was studied. Morphological studies revealed that the porosity of the resulting physical surface structure was influential in determining the corrosion rate. In deaerated 3N HCl solutions, the selective dissolution of indium was the predominant mechanism in the corrosion of In-Bi alloys. The corrosion was always accompanied by a phase change …

Optimizing Underground, Trackless Loading And Hauling Systems, Richard Lee Bullock

Doctoral Dissertations

"Determining the optimum system and equipment to be utilized in today's underground trackless haulage mine is a complex problem which was dealt with in this research by systems simulation. The computer program developed by the Caterpillar Tractor Company served as the starting point for simulating the equipment's capabilities to move material over a course in a prescribed time. Extensive time studies of the unsimulated events lead to structuring this program in the deterministic mode since it was felt to be more acceptable to the operating management which would eventually use the technique. Every phase of the simulation was successfully validated …

Bit Penetration Into Rock - A Finite Element Study, Jaw-Kuang Wang

Doctoral Dissertations

"A finite element approach has been developed to simulate bit penetration from bit-rock interaction to chip formation. A mathematical rock failure model, based on a review of the existing literature on rock tests, has been proposed to represent post-failure rock behavior and applied in the penetration simulations. The finite element program has been developed for two dimensional plane strain problems with non-linear material properties, geometrical nonlinearities and fracture. An anisotropic element as well as variable stiffness and stress release methods have been used. An iteration method, using an incremental approach, has been applied for continuous penetration and modifications of material …

Simulation Of Nonisothermal Absorber-Reactors For Multicomponent Systems, Robert E. Schwab

Doctoral Dissertations

"There are various models available for calculations involving one transferring component with chemical reaction for isothermal conditions using linear equilibrium data. However, the differential equations for multicomponent mass and energy transfer with chemical reaction have not been developed or implemented. This work demonstrates the development of a reliable model describing multicomponent mass and energy transfer in a continuous two-phase absorber-reactor for Non isothermal conditions and demonstrates the feasibility of solving the differential equations numerically. The numerical solution, using nonlinear equilibrium data, is used to obtain the absorber-reactor column specifications"-- Abstract, p. 2

Split-Film Anemometry In A Drag-Reducing Solution, Jack Chosnek

Doctoral Dissertations

"Turbulence measurements were made in the tube flow of mineral oil and a 0.2% solution of polyisobutylene in the same oil. Velocity profiles, axial and radial turbulence intensities, and axial and radial energy spectra were obtained in both fluids using a split-film anemometer probe. In addition, velocity profiles and axial turbulence intensities were obtained in oil using a 0.001-in. cylinder probe, a cone probe and a parabolic-wedge probe. The measurements were made in a one-inch tube at a constant fluid temperature of 30.0°C, in the Reynolds-number range of 4,800 to 50,000.

Four factors influenced the results in a greater manner …

Classification Of Surficial Materials, James Hadley Williams

Doctoral Dissertations

"A surficial materials classification system has been designed to fit the needs of a geologist in mapping and classifying surficial materials. The system developed in this study is intended primarily for analysis of surficial materials where time-stratigraphic markers are not applicable or recognized. Primary classification is based on fabric and mode of origin supplemented by data on engineering and pedologic properties.

Several types of classification systems presently exist for use in soil investigations. Only three of these systems have found widespread acceptance, two serving the engineering profession and the other the needs of the soil scientist. These systems are not …

An Analytical And Experimental Study Of The Dynamic Response Of A Press, Woosoon Bai

Doctoral Dissertations

"This dissertation presents a simplified mathematical model and computer simulation of the vertical motion of a press. The model is verified by comparing simulation results with actual field measurements.

Using this model, the computer simulation is then extended to study the dynamic response of a bolted press, one with loosened anchor bolts, and one which is isolated. Press performance, in terms of acceleration of the press, velocity of its foundation, and forces transmitted to the foundation, is analyzed in relation to the foundation mass and the stiffness of the isolators, where applicable. Comparative performances of the presses secured by the …

Structural Behavior Of Cold-Formed Steel Members Made Of Thick Sheets And Plates, Ai-Shen Liu

Doctoral Dissertations

"It is well-known that the current AlSI Specification for the design of cold-formed steel structural members has been developed mainly for thin steel sections. In order to extend the applicability of the specification for the design of cold-formed steel members thicker than 1/4 in., both analytical and experimental investigations have recently been conducted with special emphases on the effects of cold work on the mechanical properties of corners and the strength of bolted connections.

For the effects of cold work, previous investigations have shown that the phenomena of strain hardening and strain aging are main factors which affect the mechanical …

Uptake By Brook Trout Of Lead And Hydrocarbons From Snowmobile Exhaust: I Field Study Ii Lead And Hydrocarbon Content Of Snow After Snowmobiling Iii Laboratory Study Iv Stamina Tests, Evelyn Snodgrass Adams

Doctoral Dissertations

No abstract provided.

An Information Processing Interpretation Of Ideomotor Behavior In The Chevreul Pendulum Illusion, Randolph David Easton

Doctoral Dissertations

No abstract provided.

Interrelationship Of Energetic Particles, Plasma And Magnetic Fields In The Inner Heliosphere, Jerome Theodore Nolte

Doctoral Dissertations

No abstract provided.

Thermomechanics Of Anisotropic Heterogeneous Materials With Particular Application To Wood During The Drying Process, Yusuf Altan Meric

Doctoral Dissertations

No abstract provided.

Interaction Of Sound And Turbulence With Particular Application To The Scattering Of Sound From A Turbulent Wake, Moses Robinson Swift

Doctoral Dissertations

No abstract provided.