Digital Commons Network^™

Turbulence Measurements With A Sampling Laser-Doppler Velocimeter, P. D. Iten

Symposia on Turbulence in Liquids

A novel sampling signal processor overcomes the difficulties encountered with frequency trackers in the investigation of unseeded highly turbulent flows. This sampling system consists essentially of a swept filter, e.g. a standard RF-spectrum analyzer, a digital data memory and a storage oscilloscope. It is able to determine first-order statistical averages of turbulent flows with high fluctuation frequencies and amplitudes even at very low scattering particle concentrations. Since the velocity samples are not statistically independent of the velocity, the sampled velocity data has to be corrected in order to obtain unbiased statistical averages. A theoretical analysis and experimental investigations of the …

Promising Directions For Liquid Turbulence Research --Panel Discussion, Victor Goldschmidt, J. H. Whitelaw, V. A. Sandborn, Val Kibens, R. E. Kaplan

Symposia on Turbulence in Liquids

No abstract provided.

Chronic Toxicity Of A Copper, Cadmium And Zinc Mixture To The Fathead Minnow (Pimephales Promelas Rafinesque), John G. Eaton

United States Environmental Protection Agency: Publications

Fathead minnows were exposed to a series or concentrations of a copper, cadmium and zinc mixture during a 12.5 month chronic test in water of 200 mg 1^-1 total hardness. The metal concentrations in the mixture were selected on the basis of results obtained during previous chronic exposures to each of the metals individually in the same water. Strict summation of the chronic toxicities of the metals was not indicated when they were tested in combination. Toxic effects of the mixture attributable to copper appeared to be increased, but that attributable to cadmium was reduced. The effects thought to …

A Nuclear Power Plant Simulator, John Jacob Adams

Retrospective Theses and Dissertations

The United States' energy crisis, which has received so much publicity lately, has focused national attention on how we are to meet our energy demands. Proposed energy sources include conventional nuclear power plants, breeder reactor and fusion reactor plants, coal gasification, liquid hydrogen, solar energy, and geothermal energy. All of these except conventional fission plants are still on the drawing board or in the experimental laboratory, and are described briefly. Government and industry are betting heavily on conventional nuclear power plants. ($40 billion already spent by private utilities for 30 operating plants, 60 under construction, and 75 on order.) A …

The Design Of A Digital Data Acquisition System For Jet Engine Testing, Robert Wesley Carter

Retrospective Theses and Dissertations

This research report documents the various types of Data Acquisition Systems in use for testing jet aircraft engines. The cost trade offs and design considerations are explored for systems which employ a digital computer as the prime recording/processing element. The digital computer has revolutionized the data acquisition field, particularly in the testing of high performance jet engines. Test data can be acquired, processed, converted to engineering units, and out via high speed line printers and cathode ray tubes (CRT's). The data acquisition system operates on-line, and interleaves the random requests for data from multiple test cells by using a specially …

Accumulative Errors In Low-Level Mos-Fet Multiplexers, Lloyd Daniel Griffin

Retrospective Theses and Dissertations

This paper provides a brief historical discussion of the development of time division low level multiplexing techniques and especially emphasizes MOS-FET multiplexers currently being implemented. Error sources which may affect system accuracy and therefore must be considered in the design of the multiplexer are described. Some of the more significant of these errors: aliasing, interchannel crosstalk, static offset, transient coupled errors, and common-mode injected errors are analyzed and covered in detail. Equations expressing the overall interchannel DC crosstalk and static offset for a generalized multiplexer are derived and presented. Settling errors arising from transient events in time division multiplexers are …

A Study Of The Microwave Reflective Properties Of Aerosols, Paul Edward Speh

Retrospective Theses and Dissertations

This thesis deals with the reflective properties of selected aerosols subjected to microwave radiation. The backscatter cross section of a sphere is developed analytically as a basis for experimental verification. The most pertinent material parameters necessary for maximum reflectivity are discussed and are used to justify the aerosols selected for the experiment. The experimental procedures and the equipment calibration techniques are prefaced by a discussion of the design and the construction of the aerosol chamber and the microwave source apparatus. The experimental results and the calculated backscatter cross section of the aerosols listed are examined. Conclusions are discussed and applications …

Investigation Of Sequential Machine Design Techniques For Implementation Of A Trac Scanning Algorithm, Raymond F. Cotton

Retrospective Theses and Dissertations

This report will demonstrate the design techniques to translate a given scanning algorithm into a hardwired pre-processor. The language to be "pre-processed" is TRAC (Text Reckoning and Compiling) devised by Mooers and Deutsch. The major drawback in the current implementation of TRAC is speed. The software overhead required for string manipulations and execution of the input scanning algorithm is the major degrading factor. A TRAC machine consisting of a hardwired pre-processor to scan the input and produce formatted data for a stack oriented evaluator is proposed. The control machine for the input scanning algorithm for the pre-processor is designed using …

Considerations In The Design Of A Network Of Minicomputers, Hardy J. Pottinger

Doctoral Dissertations

"The advantages of a network consisting of a number of minicomputers coupled to a large time shared computer are described. This type of network is very useful in the areas of data acquisition, real time control of experiments, and front-end processing for computer graphics.

Problems associated with the development of a network of this type, various possible solutions, and the trade-offs involved are presented. These problems are classified into two categories: the interface between the network and the central computing facility, and the interface between the remote sites and the rest of the network.

The design constraints, rationale, and implementation …

Numerical Calculation Of The Currents In Bent Wire Antennas, Min Ho Kang

Masters Theses

"The current distribution for bent dipole antennas is numerically calculated by using a digital computer. A delta-gap at the center is assumed for the drive. Several different bend-angles are considered including the cases of the straight wire and the inverted-L. The total length of the wire considered is λ/2 while the ratio of the bent portion over the vertical portion is varied. The method of solution is based on Mei's integral equation and the method of moments. The use of Mei's integral equation eliminates the need for the application of the boundary condition at the point of bending. For …

Annals Of The Research Division, Robert C. Deen

Kentucky Transportation Center Research Report

No abstract provided.

Power, Divergence, And Stability Factors Affecting The Use Of A Krypton Laser As A Multispectral Illumination Source, David Perry Owsley

Masters Theses

"Specific performance characteristics of a krypton laser were measured. Evaluation criteria were dictated by the proposed use of the laser as a multi-wavelength illumination source. The laser output power, spectral power distribution, and output stability were measured as a function of wavelength and transverse mode order, to determine optimal operation characteristics. Data are presented defining the compromise between laser output power and beam divergence when the laser is operated multi-wavelength, and in several low-order transverse modes. There is an advantage of increased output power when the laser is operated in transverse modes higher in order than TEM₀₀, but …

Analysis And Design For Semi-Automatic And Automatic Control Of Vehicles By Permanent Magnets, Hari K. Mehta

Masters Theses

"The analysis and design carried out in this study relates to automatic or semi-automatic lateral control of a vehicle. This is one of the three essential subsystems needed for a complete automatic control system. The other two subsystems provide longitudinal control, and intersection or lane-changing control.

The system studied employs a series of permanent magnets which have been embedded vertically in the road and spaced at an interval to be used for position reference, leading to discontinuous error signal. This system has been analyzed by classical Z-transform analysis and control models have been developed for two kinds of controls. First, …

Penetration In Granite By Jets From Shaped-Charge Liners Of Six Materials, Ronald R. Rollins, George Bromley Clark, H. N. Kalia

Mining Engineering Faculty Research & Creative Works

A new application of theory for three-dimensional collapse of conical liners shows why the two-dimensional analysis may offer a good approximation. Shaped-charge design parameters and rock target properties were investigated to determine their effects on penetration and breakage. Several metals, liner thicknesses, cone angles and standoff ranges for each were investigated. Effective standoff is greater for aluminum than more dense metals. Jets from the 60° monel, brass and steel liners gave the deepest penetration in granite. Jets from copper and brass liners gave equal penetration for 42° apex angles. Liners containing zinc produced small slugs or none at all. The …

Performance Degradation Due To Specular Multipath Intersymbol Interference, G. H. Smith, David R. Cunningham, Rodger E. Ziemer

Electrical and Computer Engineering Faculty Research & Creative Works

Plots of performance degradation are used to compare the effects of fading and intersymbol interference in a two-component specular multipath digital communications channel. Similar plots are then used to compare two practical receivers designed to combat the interference. Degradation plots are shown to allow easy identification of each receiver's range of usefulness, as well as identification of variance bounds demanded of channel parameter estimates which the receivers require. Copyright © 1973 by The Institute of Electrical and Electronics Engineers, Inc.

An Analysis Of The Maintenance And Supply System Of The Atlantic Missile Range Communications Network, John Alexander Morian

Retrospective Theses and Dissertations

The maintenance and supply system of the Atlantic Missile Range Communications Network (AMRCN) is modeled to determine the optimum level of men and parts which must be available at Cape Kennedy, the source of supply, in order to minimize the level of failed equipment at the four remote sites. The system is simulated utilizing a DYNAMO model. DYNAMO is a compiler for translating and running continuous models (models described by a set of differential equations). Flow diagrams of the breakdowns, men, and parts and the information flow between these segments of the model are presented. The results obtained are discussed …

Development Of A Sixteen Line Multiplexer, James H. Stangel

Retrospective Theses and Dissertations

This report explains the development of a telephone line multiplexer to be used with a computer based personal paging system. The large geographical area coverage made possible by computer processing results in many calls having to cross telephone tariff boundaries. Since system users cannot be expected to pay long distance charges, dedicated lines which cross tariff boundaries must be leased. Multiplexing applied to those leased lines reduces the cost of data transmission, and is, therefore, justified. The design of the multiplexer proceeds from a specification set which is derived from user response requirements. Fundamentally, the response consists in advising the …

Commentary On And Extension Of Calculative Procedure For Co2 Production, Ralph M. Rotty

Mechanical & Aerospace Engineering Faculty Publications

Further refinements are made in the method of calculating amounts of carbon dioxide released to the atmosphere through the combustion of fossil fuels. Data available in the UN Statistical Yearbook are used as the basic sources rather than the summary, World Energy Supplies, U.N. Statistical Papers, Series J because the most recent data are available several months earlier in the yearbook and because data are included for natural gasoline, natural gas liquids, and cement production. Coal, lignite, crude petroleum, “marketed” natural gas, flared natural gas, and cement are itemized separately and revised CO₂ emission estimates are made for …

A Solid State Vhf Single Sideband Transmitter, Ermi Roos

Retrospective Theses and Dissertations

This research report investigates a unique method of generating single sideband power, which is particularly useful in transistorized transmitters operating at VHF frequencies. Radio frequency power id developed by class C amplifiers, rather than conventional class A or B amplifiers. Currently, VHF power transistors are not well adapted for use as linear amplifiers, and will function far better in the class C mode. A prototype VHF transmitter which develops single sideband power with nonlinear amplifiers was designed and constructed. The transmitter characteristics were measured and analyzed to establish the feasibility of the new design.

Planning Programming Budgeting Study Of The City Of Winter Park, Alfred T. Sawicki

Retrospective Theses and Dissertations

The report examines the applicability of Planning, Programming, and Budgeting System to the City of Winter Park. After briefly describing the character of the city, the goals are identified, the means by which they may be achieved and measure of evaluating progress toward them are given. To show how such an effort might be implemented, specific programs, objectives and effectiveness criteria are provided. These are followed by three examples in which the existing system is described and from which problems are revealed. Next, a brief analysis is performed to pinpoint the difficulty and a solution is proposed. The examples are …

The Application Of System Dynamics Techniques To War Game Modeling, G. Vincent Amico

Retrospective Theses and Dissertations

Military War Gaming has developed from the chess-like games to the elaborate computer simulations of today, using high-speed, general-purpose, digital computers. This Research Report will briefly review modern war-game developments with emphasis on real-time training systems. The application of system dynamics techniques developed by Jay W. Forrester to war-game modeling is explored. A simple destroyer versus submarine model is developed. Results indicate that the system dynamics modeling technique is a powerful and effective tool. However, the Dynamo language could be substantially improved by a more powerful logical statement capability.

A Study Of Rf Induction Heating And Float Zone Refining Of Silicon, John Allen Reynolds

Masters Theses

"Float zone refining using simultaneous RF induction heating and electromagnetic levitation has proven to be the best technique for producing high purity silicon for the semiconductor industry.

A study of the power requirements for floating molten zones, of load to source impedance matching, and of considerations for RF heating coil design was conducted to determine possible methods of improving the technique. It is shown that the power requirements are within reason, that impedance matching can be improved by varying network parameters, and that certain vital items must be assured in the design of different RF heating coils.

It is believed …

Management Of Passive Countersurveillance In The R & D Environment, James Ronald Carney

Masters Theses

"Existing management procedures that are pertinent to research and development activities within the Government are presented. The main focus of this effort is on the Mobility Equipment Research and Development Center’s Countersurveillance and Topographic Division, and highlights the relevant plans, documents, programs, and reporting systems utilized by the Army and the Department of Defense. An in-depth examination is made on the need for Countersurveillance in the Army. The Army’s existing Countersurveillance research and development missions and programs are reviewed.

A detailed investigation and analysis is performed on current management concepts and techniques that are utilized in research and development endeavors. …

A Study Of The Measurement Of Noise Power, Larry Smith Heflin

Masters Theses

"In order to compute a power signal-to-noise ratio in the numerical simulation of a communication system, it is necessary to measure the power of the noise present. The required integration can be approximated by many numerical techniques. Five numerical integration methods are available in the user-oriented System/360 Continuous System Modeling Program. Measurements of the power of an additive Gaussian noise waveform are performed, and an analysis of the accuracy of the measurement compared to theoretical values is presented"--Abstract, page ii.

Attitude Scaling As A Public Involvement Tool In The Lower Mississippi River Region Comprehensive Study, William A. Lee

Masters Theses

"The planner is under considerable pressure to involve the public in water resource planning. The public, however, often lacks sufficient knowledge to offer useful comments or suggestions. The use of a Likert Type Attitude Scale in the public involvement effort of the Lower Mississippi Region Comprehensive Study demonstrates the usefulness of attitude scaling techniques in obtaining public input to the planning process. The measurement of an individual's attitude, or his thoughts, feelings and disposition to act toward some aspect of his environment with some degree of consistency, gives an indication of the goals and objectives toward which a plan acceptable …

The Linear New City -- A Pattern For New Cities Based On Efficiency Of Transportation, Public Services, And Land Use, Elbridge Wesley Bartley Iii

Masters Theses

"The linear new city is defined as a city consisting of some arrangement of relatively narrow, high-density strips, served by various mass transportation systems. Such a new city would be ideally suited to the implementation of the latest technology. The concentration of development along the transportation route would allow certain economies in the supply of utilities and services, as well as insuring that open space would be readily available around and throughout the city. The provisions for transportation, housing, and governmental control should combine to produce a better quality of life for the inhabitants of the linear new city"--Abstract, page …

Land Use Development At Interstate Interchanges In Indiana, Lawrence Peter Fabbroni

JTRP Technical Reports

No abstract provided.

Operational Planning Of Fixed-Route And Demand-Responsive Bus Systems In Greater Lafayette Area, Antoine George Hobeika

JTRP Technical Reports

No abstract provided.

A Study Of Bus Transit Planning In Small Urban Areas, Michael Stephen Herman, Gilbert T. Satterly, William Louise Grecco, Kenneth W. Heathington

JTRP Technical Reports

No abstract provided.

Evaluation Of Safety Improvements At Highway - Railway Grade Crossings : Interim Report, Thomas Allan Butcher

JTRP Technical Reports

No abstract provided.