Engineering Commons^™

Effect Of Rod Gap Spacing On A Suction Panel For Laminar Flow And Noise Control In Supersonic Wind Tunnels, William D. Harvey

Mechanical & Aerospace Engineering Theses & Dissertations

It has been well established that the test section flow of conventional supersonic and hypersonic wind tunnels contains significant levels of disturbances. These disturbances are mainly caused by the radiation of aerodynamic noise from the turbulent boundary layer on the nozzle walls. This noise level has been shown to have an important effect on boundary layer transition measured on models in tunnels. The purpose of this thesis is to present results of a coordinated experimental and theoretical study of a sound shield concept which aims to provide a means of noise reduction in .the test section of supersonic wind tunnels …

An Experimental Investigation Of A Cold Jet With Solid Centerbody Emitting From A Flat Plate Into A Subsonic Free Stream, Danny K. Livingston

Mechanical & Aerospace Engineering Theses & Dissertations

A study of the influence of a solid center body on lift loss and pitching moment has been conducted. It has been well established that a round free jet emitted from a flat plate at right angles to a cross flow causes an induced pressure distribution on the plate which adversely affects the lift and pitching stability of the flat plate.

This investigation has employed a 2.58 - cm diameter round jet with a 1.91 - cm diameter solid rounded core in order to modify the induced flow field and attempt to reduce the lift loss and pitching moment. Preliminary …

Integrated Circuits, Julio Garcia

Graduate Research Papers

The technology of integrated circuits is_ almost new in Peru, writer's country-. It is being used mainly in black and white television sets and in some audio amplifier equipment. As any new technology, first, it is necessary to be very familiar with it in order to exploit it adequately and get all the benefits from it. The writer feels this lack of knowledge, and wants to take advantage of being here to learn the technology and techniques for using integrated circuits.

A Circular Active Reflector Atenna (Cara), Energy Distribution Calculations, And An Experimental Test, Larry V. Knight, George H. Barry

Faculty Publications

Conventional high-frequency (HF) circular phased arrays, such as the Wullenweber circular array, have a cost factor that increases at a greater-than-square law rate as its radius is increased to produce larger apertures. A new method of forming simultaneous beams in an HF circular array has been proposed in which beams are formed in the space within the array from pickup element energy that has been amplified and reradiated. Such a device is called a circular active reflector antenna (CARA), and its cost increases at a substantially linear rate as its radius is increased to form larger apertures. This paper describes …

At-Grade Intersections Versus Grade-Separated Interchanges (An Economic Analysis Of Several Bypasses), Kenneth R. Agent

Kentucky Transportation Center Research Report

In an effort to reduce traffic in central business districts, bypasses have been built to provide through traffic a circumferential route and also to ease the burden of traffic in downtown areas. In many cases, though, bypasses have created a serious accident potential because they were built with at-grade intersections and no access control. This has led to commercial developments along the bypass and congestion at major intersections. When congestion increases at an intersection, traffic signals must be installed; this increases vehicle operating and time costs and creates a rear-end collision potential. In some cases, the bypass circumvents a relatively …

Engineering Data System For Bedrock Occurrences And Properties, D. J. Hagerty, Robert C. Deen, M. W. Palmer, C. D. Tockstein

Kentucky Transportation Center Research Report

The initial work plan included the development of a classification system based on index tests. An investigation of previous works in classification of rock on the basis of index tests showed that a variety of classification systems utilizing many different index tests had been developed. However, this survey showed that no generally applicable system had been developed and that little communication had been established between field investigators, facility designers, and those in charge of construction and maintenance of facilities. Therefore, the initial plan for work was modified to include the development of a comprehensive methodology for evaluation of rock. The …

Pedestrian Accidents In Kentucky: 1972-1973, Charles V. Zegeer

Kentucky Transportation Center Research Report

Pedestrian accident data in Kentucky were analyzed for 1972 and 1973 on a rural, urban, and statewide basis. Results showed that about 1500 pedestrian accidents occur in Kentucky each year and cost over $11 million. About 30 percent of pedestrian accidents in rural areas and 4 percent in urban areas are fatal. Although about 78 percent of Kentucky's pedestrian accidents occur in urban areas, over 62 percent of the pedestrian fatalities occur in rural areas.

Specific characteristics of pedestrian accidents were identified and related to human, environmental, and time factors. Highway and street improvements and safety programs generally considered to …

Vehicle Noise Survey In Kentucky, Kenneth R. Agent, Rolands L. Rizenbergs

Kentucky Transportation Center Research Report

Individual noise measurements were obtained on 10,500 motor vehicles operating on Kentucky highways. The roadways were selected to represent varied geometric and environmental conditions and posted speed limits. Percentages of automobiles and trucks exceeding a given level of noise were determined. As expected, noise levels of trucks were significantly higher than for automobiles, and larger trucks produced higher noise levels than smaller trucks. For any vehicle type, noise increased with an increase in speed limit.

Temperature Distributions In Asphaltic Concrete Pavements, Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

The straight-line relationship between temperatures at a given depth and the surface temperatures combined with 5-day average air temperatures appears to be as valid for upper New York state and Arizona as for Maryland. The main differences were in the annual ranges and annual mean temperatures. The concept for estimating pavement temperature distributions appears to be valid and may be used with confidence for estimating pavement temperatures at all latitudes and longitudes.

Ellipsometric Function Of A Film-Substrate System: Applications To The Design Of Reflection-Type Optical Devices And To Ellipsometry, R. M.A. Azzam, A.-R. M. Zaghloul, N. M. Bashara

Electrical Engineering Faculty Publications

The ratio ρ = R_p/R_s of the complex amplitude-reflection coefficients R_p and R_s for light polarized parallel (p) and perpendicular (s) to the plane of incidence, reflected from an optically isotropic film-substrate system, is investigated as a function of the angle of incidence ϕ and the film thickness d. Both constant-angle-of-incidence contours (CAIC) and constant-thickness contours (CTC) of the ellipsometric function ρ(ϕ,d) in the complex ρ plane are examined. For transparent films, ρ(ϕ,d) is a periodic function of d with period D_ϕ that is a function of ϕ. …

Electron Trajectories In The Vicinity Of A Wire Mesh Placed Parallel To A Perfectly Conducting Ground Plane, Donald E. Jones

Electrical and Computer Engineering ETDs

In the System Generated Electro-Magnetic Pulse (SGEMP) simulator, a flux of high energy photons are introduced into a vacuum chamber. These photons strike the walls of the chamber, producing compton electrons. As this effect is not present in the environment to be simulated, it is desirable to prevent these electrons from entering the working volume of the chamber.

Stresses At The Tips Of Cracks Emanating From The Loaded Fastener Hole, Venkataraman Shivakumar

Mechanical Engineering ETDs

Stress-intensity factors, K, are obtained at the tips of radial cracks emanating from the boundary of an internal circular fastener hole in a plate loaded by a pin or rivet that just fills the hole and is pulled in the negative y-direction, in the plane of the plate. Solutions are obtained in a conformally mapped region in the form of series for different crack lengths and are based on the Muskhelishvili formulation in the two-dimensional theory of elasticity. The method presents a general technique for determining K for k symmetrically located radial cracks of equal length for a wide variety …

Wave Induced Pressures On Submerged Plates, William W. Durgin, Jong C. Shiau

Office of the Provost Scholarship

The prediction of forces, or more precisely, the pressure distributions, experienced by submerged structures due to the passage of gravity waves has become important with the advent of large offshore structures. If the size of a structure is small compared to the wavelength then the forces can be evaluated by the assignment of suitable drag and inertia coefficients using an approach similar to that of Morison (6) in which case it is necessary to determine the coefficients experimentally for any given geometry (2). If the size of the structure is a significant fraction of the wavelength, the preceding method is …

Data Acquisition And Management For Rock Evaluation, M. W. Palmer

Kentucky Transportation Center Research Report

The primary goal of this thesis was the formulation of an integrated effort to collect, maintain, exchange, and evaluate engineering data on rock materials from a variety of information sources. The proposed rock evaluation program provides a data base of accumulated information by establishing procedures for characterizing rock, from specimen acquisition through indexing, classification and correlation studies of data, and the application of data for site selection, use tables, establishment of design parameters and alternatives, and maintenance of engineered facilities. The co-ordinated evaluation system detailed herein provides guidelines for implementation of an extensive system of data storage and retrieval to …

Cost Comparison Of Short Span Bridge Structures, Alan R. Main

Indiana Local Technical Assistance Program (LTAP) Publications

This report attempts to give the county engineer a guide for estimating the cost of several types of bridge structures for a particular situation.

Effect Of Pavement Texture On Traffic Noise, Kenneth R. Agent, Charles V. Zegeer

Kentucky Transportation Center Research Report

Tire noise is one of the primary sources of highway noise, particularly at high speeds. Different types of road surfaces generate different noise levels. Noise data were collected on eight different surface types found in Kentucky. Noise measurements were made using a reference car, and noise recordings were obtained from the traffic stream. A reference truck was used for one test. It was found that portland cement concrete; Class I, Type A and A(Modified) bituminous concrete; chip seals; and open-graded, plant-mix seals were more or less "normal" surfaces in regard to generated noise. Sand-asphalt and Kentucky rock asphalt surfaces were …

Some Structural Aspects Of Ni2+ In Potassium Haloborate Glasses, Samia Sidhom

Archived Theses and Dissertations

No abstract provided.

Design Of A Yig-Tuned Oscillator, Tien Liang Jin

Theses

A technique for designing YIG (yttrium-iron garnet) tuned transistor oscillators, tunable over the range of frequencies from 500 to 950 MHZ, is presented. The approach taken differs appreciably from that used in the design of conventional LC-tuned oscillators. One major difference is that the YIG tuning mechanism is electrically controlled. The YIG tuning element is treated as a single unit and is not resolved into an equivalent LC circuit. Instead, a direct method using reflection coefficients measured at network terminals to characterize various design stages is applied. The transistor is also characterized by reflection and transmission coefficients, i.e., S-parameters. Thus …

The Design Of Optimal And Sub-Optimal Feedback Controllers For Discrete Systems, Chaw-Kwei Hung

Electrical and Computer Engineering ETDs

This dissertation is divided into two parts. The first part presents a method for the design of time-optimal feedback controllers for linear discrete stable systems with a single bounded input. In the second part, a method is presented for the design of time sub-optimal feedback controllers in which a tight upper bound on the time sub-optimal feedback controller's performance for state points in a convex polyhedron can be guaranteed. Two sets related to the reachable set--the zero control set and the cylindrical set--are formulated. Both are helpful in the realization of the time-optimal feedback controller. The cylindrical set is composed …

Hmo, A Hardware Microcode Optimizer, James O. Bondi, Paul D. Stigall

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Discusses an Algorithm for Optimizing the Density and Parallelism of Micro coded Routines in Micro programmable Machines. Besides the Algorithm itself, the Algorithm's Uses, Adaptability to Conventional Machine Characteristics, and Architectural Requirements Are Also Discussed and Analyzed. Even Though the Paper Proposes a Hardware Implementation of the Algorithm, the Algorithm is Viewed as an Integral Part of the Entire Microcode Generation and Usage Process, from Initial High-Level Input into a Software Microcode Compiler Down to Machine-Level Execution of the Resultant Microcode on the Host Machine. It is Believed that, by Removing Much of the Traditionally Time-Consuming and Machine-Dependent …

Instruction Design To Minimize Program Size, James F. Wade, Paul D. Stigall

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Creating The Electric Energy Economy, L. G. Hauser

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

My remarks will be directed to four points:

First, that energy is the life blood of our economy, and that its use or conservation is far from a simple matter of personal habits of waste or frugality. In other words, the vital role energy plays in the production of goods and services should be distinguished from its use in their consumption.

Second, that our excessive dependence on our two scarcest energy resources -- oil and natural gas -- is the core of the energy problem, both U.S. and worldwide.

Third, that limiting our time horizon to this winter, next summer, …

Energy And Transportation Policy, James S. Sagner

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Energy shortages of recent years suggest a re-examination of national transportation policy. The lack of a coordinated approach to the solution of urban cogestion inhibits potential short-run responses to gasoline shortfalls. Longer-range policy, particularly in the context of severe financial constraints, must be carefully integrated with demonstrated patterns of urban travel and population and employment densities. Given these considerations, metropolitan areas now planning or constructing rapid rail facilities may be selecting inappropriate responses to the problem of urban access.

The Design And Performance Of A Distributed Flow Water-Cooled Solar Collector, Donald L. Spencer, Theodore F. Smith, Herbert R. Flindt

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Design of a flat plate collector which reduces the temperature differential between the absorber plate and the fluid is described. The reduced temperature differences are shown to yield increase collector performance. Flow characteristics of the collector are examined. Collector thermal performance is illustrated for typical operating and environmental conditions. A cost analysis is presented to demonstrate that material and assembly costs are substantially lower than for any collector presently on the market.

How Might Synthetic Fuels From Coal Affect Natural Resources And Environment?, H. J. Plass Jr.

UMR-MEC Conference on Energy / UMR-DNR Conference on Energy

Energy self-sufficiency for the U. S. requires substantially increased use of coal. Direct combustion of coal without adequate environmental controls, as would occur if coal were used as a fuel for homes and offices throughout the country, would result in severe air pollution problems„ Synthetic fuels from coal such as methane, low BTU gas, or hydrogen, when utilized by the homes and businesses as gas or as electricity from gas, will contribute a much smaller amount of air pollution. However, to make these synthetic fuels available, it is necessary to mine more coal than would have to be mined for …

Two-Dimensional Analysis Of The Coherent Instationary Motion Induced By An Obstacle, Using Electrochemical Methods, B. Py, C. Tournier

Symposia on Turbulence in Liquids

The non stationary flow induced by a cylinder with a square cross-section was studied on the cylinder's surface and in the wake with two different electrochemical probes. On the cylinder was mounted split rectangular electrodes with high enough aspect ratio so as to measure the chordwise component of the wall shear stress with its sign. The non-linear response of this transducer was studied. In the wake, the longitudinal component of the velocity was obtained with conical electroactive elementswhich are mainly sensitive to this component.

The fluctuating coherent components are separated from the aleatory part of the signal and then decomposited …

Author Index, University Of Missouri--Rolla

Symposia on Turbulence in Liquids

No abstract provided.

Subsolidus Equilibria And Metastable Phase Development In The System Zro₂-Al₂O₃-Sio₂, Charles Christopher Sorrell

Bachelors Theses

"Subsolidus equilibria in the low silica portion of the system ZrO₂-Al₂O₃-SiO₂ were studied by X-ray diffraction of quenched samples fired at 1300°, 1400°, and 1480°C. Samples prepared as powders from combinations of a-Al₂O₃, Al(OH)₃, silicic acid, ZrO₂, and kaolinite reacted very slowly at 1300° and 1400°C and the trends toward equilibria are not apparent. A mixture of zircon and Al(OH)₃ reacted slowly at 1480°C to form mullite and ZrO₂, indicating that the latter phases are the stable assemblage rather than zircon and alumina. A gel prepared from aluminum nitrate, zirconyl nitrate, and colloidal silica reacted at 1480°C to form alumina, …

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 …

A Study To Determine The Cultural Awareness Of Engineering Students, Gordon P. Foreman

Undergraduate Honors Capstone Projects

Origins of the Study

As an engineering student in the Honors Program, I am continually faced with the stereotype of engineering students as people with no interest in social or cultural affairs and no consideration of things which cannot be tied down and measured. I decided to test this conception as best I could, even to comparing engineering students quantitatively to natural resources, history, and business majors. I attempted to get number comparisons for the index of relative awarenesses of culture. I suppose that only an engineering student would have the temerity to try to attach numerical values to something …