Digital Commons Network^™

A Study Of Stability Of Ac And Dc Transmission Lines Operated In Parallel., Tzyy-Cheng Wang

Masters Theses

"This thesis is concerned with the analysis, optimization and simulation of parallel operation of ac and de transmission lines.

An introduction and literature review are provided to give background information on how the parallel operation should be considered. The parallel system is analyzed, and the state equation is derived for determining the stability limit. The optimization of the control law U = Fx is determined by a standard quadratic cost function. Prefault, during fault and postfault situations in the parallel operation has been simulated by Continuous System Modeling program. Some comparison and comments are made between 1 ac, 1 de …

Documentation Of A Short Circuit Program For Fault And Protection Studies., Alejandro Gonzales

Masters Theses

"For a given power system of no more than 100 buses and 400 line ends (source lines have one line end, radial lines have one line end and regular lines have two) a digital computer program is presented which determines the short circuit currents needed to implement a protective relaying design, The program uses the ZBUS method of analysis and calculates the currents at all buses, searches for the maximum and minimum values of the current contributed by the lines connected to the faulted bus under normal conditions (all lines in) and under single and double line outages. Maximum and …

An Analysis Of A Network Of Finite-Queue, Multiple-Server Facilities., Juanita Kaye Shukers Grau

Masters Theses

"An algorithm for listing all possible steady states and for generating the transition matrix for a series of finite-queue, multiple-server facilities is described. This algorithm is compared to a previously developed one. The new algorithm is better since it works for multiple servers and does not require an extra pseudo-facility. Using the list of states and the matrix generated by the new algorithm, exact steady state probabilities can be calculated. Then the probabilities can be used to obtain system statistics which cannot be calculated otherwise"-- Abstract, p. ii

Fluid Inclusion Geothermometry Of Tri-State Sphalerite, Chi-Sheng Wei

Masters Theses

"Fluid inclusions in successively deposited generations of sphalerite from the Tri-State district have been examined for geothermometry as a function of time. The main stage of vug-filling sphalerite has been studied most intensively and as many as 83 fluid inclusions have been examined in a single crystal. These sphalerite crystals are commonly zoned, and their filling temperatures exhibit a general pattern of declining temperature from their cores outward, from about 135°C down to 90°C. The decline is not a steady one, but rather it is characterized by fluctuations commonly about 15-20°C. Some fluctuations have magnitudes as great as 50-60°C, with …

Heavy Metal Contamination In Soil Around A Lead Smelter In Southeast Missouri, David Lewis Butherus

Masters Theses

"In order to determine the extent of possible heavy metal contamination, more than 963 samples of leaf litter and soil were collected from 410 sample stations around the AMAX smelter in southeast Missouri. Dried samples of leaf litter and minus 80 mesh soil fractions were analyzed for cadmium, copper, lead, and zinc by atomic absorption spectrophotometry. Minus 80 mesh soil fractions were also analyzed for sulfur using x-ray fluorescence methods. Ranges of heavy metal concentrations in leaf litter were: cadmium, 0.13 μg/g to 175 μg/g; copper, 4.2 μg/g to 6500 μg/g; lead, 50 μg/g to 130,000 μg/g; and zinc, 26 …

Effects Of Colloidal Materials And Polyelectrolytes On Carbon Adsorption In Aqueous Solution., Jack Taylor Garrett Jr.

Masters Theses

"The purpose of this study was to investigate the effect of certain colloidal materials and long-chain polyelectrolytes on the adsorption efficiency of some selected activated carbons which were manufactured from both coal-based and lignite-based materials. Phenol was used as the adsorbate to determine the adsorption efficiency.

At the beginning of the study, four brands of activated carbon (i.e. Filtrasorb 400, Darco, Norit, and Witco 256) were tried, based on the preliminary adsorption data, two activated carbons were subsequently selected for use throughout the entire study. These were Calgon's Filtrasorb 400 and American Norit's Norit activated carbons. The former represents a …

The Availability And Development Of An Automated Accounting System For Small Businesses., Margy Rice Beckmeyer

Masters Theses

"A good accounting system is a very essential part of the successful operation of a small business but is often lacking. Therefore, the objective of this research is to furnish a general automated accounting system suitable for use by the small business firm.

To determine the feasibility, a statistical survey was made to evaluate the availability of automated accounting systems now available to small business. The results of the survey suggest that computer systems are presently available to small business firms at economical prices, but to minimize cost the small firm may need to supply its own accounting program.

The …

An Analysis Of The Role And Effectiveness Of The Contract Manager In Government Contracting., Daniel Martin Wilson

Masters Theses

"The contract manager in carrying out the contract management function of government contracting represents a vital element of the procurement process. He is charged with responsibilities for assuring that a product or service is delivered in a timely manner and is of specified quality, quantity and price. However, research and a survey of his role reveal that he is regarded a s a functional specialist, guided by a mass of procedural requirements, and he is not included in the managerial hierarchy of contracting.

Because his role does not accord him the status or authority commensurate with the importance of the …

Planned Unit Development: A Comprehensive Analysis Of A New Approach To Community Living., John Raymond Weese

Masters Theses

"Undeveloped land in America has been one of our most cherished natural resources for many years. Yet, land development has often been haphazard and extremely wasteful.

This paper presents a comprehensive analysis of one particular method for developing land which utilizes land efficiently, but which also respects the natural characteristics of a land development site. The Planned Unit Development process is such a method, and it is the subject of this paper.

The Planned Unit Development concept is an outgrowth of the planned community concept which has existed for many years. However, only recently has the Planned Unit Development concept …

Image Detection In Signal Dependent Noise., Robert D. Laramore

Masters Theses

"This thesis deals with the detection of two-dimensional signals in the presence of noise, including signal dependent noise. The object to be detected and the background are assumed known a priori. A decision rule based on a likelihood ratio test is obtained and the associated probabilities of detection and false alarm are evaluated. This is done first in general terms, where neither the form of sampling nor the model used for noise is specified. Then results are obtained for three examples: Poisson noise, signal dependent Gaussian noise, and binomial noise. Finally, the degradation resulting from a point spread function is …

A Study Of Trace Organics And Trace Organic-Bound Metals In Raw And Finished Waters., Robert Lee Stewart

Masters Theses

"The main objectives of this study were: (a) to prepare a comprehensive review and evaluation of the literature pertaining to trace substances, with emphasis on their status in water supplies, health effects, and fate in treatment; ( b) to establish the methodology needed for measuring trace metals in trace organic substances; and (c) to determine the metal content of organic extracts recovered from surface, subsurface, and finished waters.

Raw and finished water was obtained at the Sedalia, MO, water treatment plant, and 5 sources were sampled (3 surface, 1 well, 1 plant-treated). The 0-CA* and SEM procedures were employed to …

The Spheriodization Of Tool Steels., Siri Ram Rai

Masters Theses

"Four different tool steels--AISI 01, Sl, A9 and Tl5--were obtained in the 1/2-inch diameter hot rolled and air-cooled condition from the steel mill. The lower critical temperatures of these steels were determined. The spheroidization of each steel by three different spheroidizing procedures was evaluated with the use of hardness testing and metallographic techniques. Isothermal annealing completely spheroidized each steel yielding coarse carbides and low hardness. Cyclic annealing was an effective spheroidization procedure only for 01 and Tl5 steels. Hardening and tempering resulted in rather fine spheroidized structures in these steels. The total time consumed to produce the best spheroidized structures …

Wastewater Treatment With Activated Carbon., Chia-Soui Joseph Lu

Masters Theses

"The objectives of this study was to determine the capabilities of selected types of activated carbon as an adsorbent for the removal of organic materials from municipal wastewater and sludges. The organic sources included primary and secondary clarifier effluent, blended sludge, and digester supernatant. Two other organic sources, glucose and alanine, were also examined to determine their removal from aqueous solution by activated carbon adsorption.

The organic impurities, in terms of chemical oxygen demand (COD), were reduced from 68 mg/1 in the primary effluent and 35 mg/1 in the secondary clarifier effluent to approximately 15 mg/1 for both. However, the …

Estimation Of Vehicle Transfer Functions., Leonard Francis Laskowski Iii

Masters Theses

"This study is an investigation of several techniques used to estimate lateral control models for vehicles. The lateral control model that was identified related steering wheel angle input to lateral acceleration output. Two different order models were identified, one a biquadratic and the other a fourth order lowpass system with second order numerator dynamics. The two main approaches investigated were:

1) Regression analysis

2) Fast Fourier Transform Techniques These techniques were chosen because of their inherent immunity to noise.

A CSMP simulation of all identified models was then made to determine their validity. These checks were made using laboratory data …

Ultrasonic Instrumentation And The Dynamic Evaluation Of Asphalt-Aggregate Mixtures., John Edward Hill

Masters Theses

"Ultrasonic probes have been constructed for use in the dynamic and nondestructive testing of asphaltic concrete specimens. The probe systems exhibited characteristics superior to the solitary ii use of their main components, the piezoelectric crystals. The probes have the advantages of the reduction of ringing time, the concentration of ultrasound in one direction, the elimination of "noise" due to unshielded connections and the increased durability of the probe system.

The probes constructed were used in a limited testing program. Compression and transverse wave velocities in the specimens tested were measured simultaneously. Sample conditions suitable for maximum wave velocity corresponded to …

Disposal Of Lead And Zinc Cationic Wastes On Soils., Stephen Melvin Linnemann

Masters Theses

"The sorption and desorption of lead and zinc on soil samples from the "New Lead Belt" of southeastern Missouri and from Springfield, Missouri, were investigated using both column and batch systems. These cations were selected for study because of the possible effects which soil pollution in the "New Lead Belt" mining region could have on shallow aquifers and because both metals are utilized in the electroplating industry.

It was found that soil has the ability to sorb lead and zinc; however, the cation-exchange capacity (C.E.C.) of the soils studied was not fully satisfied, though there was evidence that i f …

Experimental Study Of Electron Density And Confinement Time In An Electrostatically-Plugged Cusp Device Using A Microwave Interferometer, Robert Louis Hayward

Masters Theses

"The average electron density and electron confinement time in an electrostatically plugged magnetic spindle cusp device are studied using a 20 GHz microwave interferometer. The results are compared with the predictions from approximate theoretical equations. With a magnetic induction in the point cusp of 5000 Gauss, a plasma is produced by injecting a 5 mA, 500 eV electron beam into hydrogen gas at 10^-5 Torr. The measured electron density is 2 x 10^-10 cm^-3 and the measured confinement time is 80 ysec, which agree to within a factor of two with values predicted by theory"--Abstract, page ii.

Geochemical And Biogeochemical Studies In The Hansonburg Mining District, New Mexico, Alan Nathan Silverman

Masters Theses

"The Hansonburg mining district is in Socorro county in south central New Mexico. A Paleozoic section of thick Pennsylvanian limestone units, thin shale and arkose layers and thick Permian units of sandstone, siltstone and gypsiferous beds interlayered with thin limestone units unconformably overlie a Precambrian basement of granite. The sedimentary rocks are folded with north trends and plunges. Northerly, some easterly and northwesterly trending faults cut the folds. Galena, fluorite, and barite mineralization occurs along some of the northerly faults and as bedded replacements and fissure fillings in the Pennsylvanian Council Spring limestone.

Geological mapping and geochemical soil surveys of …

"Project Dial": An Early Childhood Screening Program, Lewis S. Sarff

Masters Theses

This field study addressed the problem of "actively seeking" out and identifying children (ages 3 to 5 years) likely to develop late learning problems upon school enrollment. The procedures developed and reported in this paper deal with initial public relations, facilities, personnel, an evaluation instrument Developmental Indicators for the Assessment of Learning (DIAL), hearing and vision testing, and reporting of results to parents and school personnel.

The paper also includes means and standard deviations for DIAL subtest scores by one year age groups and by sex, as well as simple and multiple r's for each of the DIAL variables individually …

Effect Of Variation In Manner Of Oral Reading On The Fluency Of Nonstutterers, Saralynn Scott

Masters Theses

No abstract provided by author.

An Analysis Of Industrial Marketing Practices And Strategies Of Nigerian Manufacturers, Efiong John Etuk

Masters Theses

No abstract provided by author.

A Basis For Articulation In Community Unit No. 2 Schools, Crawford County, Illinois, Carl E. House

Masters Theses

No abstract provided.

Major Trends In The Explanation Of Direct International Investment, Mark Grier

Masters Theses

No abstract provided.

ComparacióN De Las Novelas DoñA Perfecta Y Silas Marner, Margarita Means

Masters Theses

No abstract provided.

Identification Of Exemplary Secondary Media Practices Within The Southeastern United States, Donald T. Beagle

Masters Theses

No abstract provided by author.

A Manual Of French And German Lute Notation, Elizabeth Carson

Masters Theses

No abstract provided.

An Investigation Of Receptive And Expressive Pluralization And Tense Inflectional Skills Of Three Year Old Children, James Michael Coffman

Masters Theses

No abstract provided by author.

A Parametric Investigation Of The Validity Of 1/25 Scale Automobile Aerodynamic Testing., Marvin Eugene Doberenz

Masters Theses

"Wind tunnel tests have been performed measuring the aerodynamic forces and underbody boundary layer profiles for 1/25 scale models. The trends of the force coefficients with Reynolds number, the underbody boundary layer profiles, and the influence of the ground plane boundary layer on the force coefficients of small-scale models has been shown to be similar with previous results from larger models. This study has shown the usefulness of small-scale models for parametric studies of automobile aerodynamics. The agreement of the data with previous results, also supports the possih1lity o f a method of correction for boundary layer growth on fixed …

A Master Data Bank In Power Systems., Nittaya Hokierti

Masters Theses

"A Master Data Bank (MDB) is used to prepare the data sets of large power system networks for later study. The MDB program has been developed to be compatible with data and formats used in load flow and short circuit studies. The MDB can store up to six sets of base case data. Magnetic disk storage is used as the storage medium to obtain adequate data storage and faster access to the data. The size of storage can be expanded by modification of statements in the MDB source program and job control statements. The data sets in the MDB can …

A Unit Hydrograph For The Missouri Ozark Region., Melvin G. Schaefer

Masters Theses

"Eleven small watersheds from the Missouri Ozark region are used in generating a synthetic unit hydrograph. The analysis is composed of three parts: First, a prediction equation is developed which correlates the time lag parameter with the physical features of the watershed. Second, an equation is developed which predicts the peak flow ordinate for 30-, 60- and 120-minute unit hydrographs. Third, an average dimensionless unit hydrograph is determined"-- Abstract, p. iii