Digital Commons Network^™

An Investigation Of Indeterminate Structures Stressed Beyond The Proportional Limit, Jack B. Joyce

Civil Engineering ETDs

In the structural field the methods of designing have been geared to the development of materials...In a more current appraisal we see steel and concrete being updated still further. Pre-stressed concrete is a common sight in present day construction work and, to a lesser extent, the educated eye sees rigid frames designed to ultimate load criteria. Here again are cases where materials are studied and found to possess characteristics that are adaptable to advance methods. The key to all such improvements is still the realization and utilization of material properties.

An Acoustic Simulator For Modeling Backscatter Of Electromagnetic Waves, Allen R. Edison

Electrical and Computer Engineering ETDs

Model experiments are commonly employed in situations where a full-scale experiment is uneconomical and where exact theoretical analysis is very difficult. The physical problem is scaled to convenient laboratory dimensions and a means is provided for controlling and measuring the parameters of the experiment. Measurements made in the model system are required to provide information on the time and space variations of functions which describe the real system. When interpreting results it is frequently necessary to consider "scale effects" which arise from certain parameters exerting a different influence in the model than in the real system.

Propagation Between Conducting And Nonconducting Media, Richard H. Williams

Electrical and Computer Engineering ETDs

This paper contains a study of the electromagnetic fields caused by electric dipoles located within a highly conductive medium such as the sea. The theoretical treatment of this problem was begun in 1951 with Moore's thesis. "The Theory of Radio Communication between Submerged Submarines." Some subsequent major theoretical treatments of this problem have been published by Wait and Campbell, Lien, Banos and Wesley, and Anderson. All of the above work stems from Sommerfeld's classic paper published in 1909 where he considers the fields in the air caused by a vertical electric antenna located on the interface between the air and …

An Investigation Of The Behavior Of Asphalt Stabilized Sand In Triaxial Compression Testing, Joseph P. Callahan

Civil Engineering ETDs

More and more in highway construction, the engineer is faced with the problem of locating satisfactory materials to be used in the construction of highways. This problem has become very critical in the selection of a satisfactory aggregate to be used in many phases of the construction. In large metropolitan areas and in other regions of the United States unblessed with an abundance of this aggregate, it was found that where once there was no shortage of suitable material, the supplies have now been practically exhausted.

A Study Of A Nonlinear Compensation Network In A Feedback Control System, John F. Taylor

Electrical and Computer Engineering ETDs

This paper is a study of the effect of a nonlinear compensation network on the closed-loop response of a feedback control system.

Physical energy dissipation elements, unlike their usual mathematical models, are often nonlinear. An example of such a nonlinear element is the mechanical damper. Since dissipation elements are used in most types of compensation, the problem of nonlinear compensation is an important one.

The study was performed with two goals in mind. The first was to determine the detrimental effects resulting from the insertion of the nonlinear network. The second was to see if any improvement in system performance …

A Shell-Theory Analysis Of Transient Thermal Stresses In Moderately Thick-Walled Cylinders, Thomas K. Mckinley

Mechanical Engineering ETDs

This paper investigates the validity of extending the concepts of shell theory to transient thermoelastic problems involving moderately thick-walled shells. The region of study is a moderately thick-walled cylinder which is constrained radially at both ends and is exposed to a uniform, time-dependent heating (or cooling) at one end. The cylinder walls are assumed to be adiabatic, and inertia effects are neglected in the development.

It is concluded from the results of this investigation that the extension of shell theory to moderately thick-walled cylindrical regions subjected to axial, time-dependent temperature variations is an analytical method of approach.

Analysis Of Radio Wave Propagation Over An Atmospheric Ground Layer By The Ray Tracing Method, Donnelly J. Johnson

Electrical and Computer Engineering ETDs

Previous efforts to analyze radio wave propagation in the troposphere have shown by agreement with experimental results the validity of the use of geometrical optics and the assumption of atmospheric spherical symmetry.

Evaluation Of The Thermal Properties Of Plastic Laminates, Luciano Sedillo

Chemical and Biological Engineering ETDs

To insure the proper application of newly developed materials, it is necessary to evaluate their physical and chemical properties. In the case of plastic laminates for use as heat barrier material, thermal diffusivity is an important property. Thermal diffusivity is the parameter which governs the rate of temperature change through a material. Its value depends upon the chemical composition and the physical structure of the material and its temperature.

An Experimental Study Of The Production Of Metallic Impregnations And Coatings -- A Vacuum Process, Engle D. Southard

Chemical and Biological Engineering ETDs

The purpose of this study undertaken was threefold, (1) to design and construct an experimental vacuum apparatus to produce a metal impregnated or coated material; (2) to study some of the variables which affect the process; then (3) to examine the physical characteristics of the resultant materials. Described herein is the development and operation of a vacuum system capable of producing conditions to permit the evaporation of metals to impregnate and coat various materials. The fundamental principle involved in this process is that a rarified atmosphere reduces the temperature required for metal evaporation and protects the metal vapor from reacting …

Cerenkov Radiation From An Electron Traveling In A Circle Through A Dielectric Medium, John Joseph Newman

Optical Science and Engineering ETDs

Two hardware configurations are discussed which might be used as vehicles for checking the accuracy of the theory. It is hoped that one of these configurations might lead to a device which would yield a useful amount of power in the submillimeter region of the microwave spectrum.

Comparison Of Pulse And Fm Radar Altimeters Based On Terrain Return Theory, David L. Quinlan

Electrical and Computer Engineering ETDs

In this paper a comparison of pulse of fm radar altimeters is made from the standpoint of the mathematical expressions describing each system’s return signal from terrain at near-vertical incidence. The pulse-fm radar relationships resulting from this comparison facilitates application of the extensive information gained in previous pulse radar studies to the investigation of fm radar terrain return and the associated design of fm radar altimeters, and may also assist in the development of the new pulse-type radars.

The Effects Of Operating Variables On The Adsorption Of Water From Iso-Propyl Alcohol Using Molecular Sieves, Warren P. Johnson

Chemical and Biological Engineering ETDs

The purpose of this paper is to present a study made on the effects of (1) feed concentration, (2) liquid flow rate, (3) column dimensions and (4) absorbent particle size on the selective absorption of water from iso-propyl alcohol with molecular sieves in a semi-continuous or fixed-bed operation.

A Flotation Process For The Concentration Of New Mexico Oolitic Iron Oxide Ores., William C. Rahmig

Chemical and Biological Engineering ETDs

The vast expansion in the production of steel in the twentieth century has turned the eyes of the steel industry toward sources of low grade iron ore. Evidence of this is dramatically presented in a recent issue of Steel Facts. Fifty two percent of the iron ore mined in the United States was concentrated before shipment to the consumers. This is an increase of 25 percent over the amount concentrated a decade ago. The marked increase will continue as technological advances light the way for economical are treatment.

Induction Heater Temperature Controller, Raymond A. Gore

Electrical and Computer Engineering ETDs

The author was presented with a system to control the power output of a radio frequency oscillator used for induction heating. The original system was unstable. It was stabilized but even then its performance was not satisfactory. Thus the problem was to design a satisfactory system using some of the components of the old system.

Conditional Effects In The Transistor Distributed Amplifier, Herbert D. Arlowe

Electrical and Computer Engineering ETDs

No abstract provided.

Adaptation Of Beggs Deformeter Apparatus To The Solution Of Three-Dimensional Problems, Roland L. Finley

Mechanical Engineering ETDs

In the area of structural analysis and structural design, numerous efforts have been made and more are yet to be made toward solving statically indeterminate problems easily and with a high degree of accuracy. Fortunately, the great majority of such problems can be solved by one or more of the many mathematical methods that are normally used. However, the mathematical solutions become exceedingly difficult if and when it is desired to use irregularly shaped structural members.

Digital Computers And Their Application To Civil Engineering Problems, Richard G. Vaughan

Civil Engineering ETDs

Early in 1960 a study was undertaken by the author to become acquainted with the use and application of digital computers in the structural and civil engineering fields. After several months study and attendance, during the summer of 1960, at a National Science Foundation Institute on the use of digital computers in engineering, it was felt that the study could be expanded and presented in thesis form. The principal benefit from the study, other than the author's, will possibly be the integration into the civil engineering curricula of the material contained in the thesis.

The material as presented is the …

A Method Of Measuring Temperature Changes Casued By Strong Shock Phenomena, Benjamin J. Goodier

Electrical and Computer Engineering ETDs

This thesis is concerned with the development of a method to measure the temperature of a metal surface during a time interval of a few microseconds while it is being subjected to a strong shock. The temperature of a special interest is the temperature of the free surface which appears after a strong shock has been reflected from that surface. This temperature remains constant until another shock wave is reflected from the surface, except for the change caused by heat loss to the surroundings by radiation.

A Conversion Means Between The Crc-102a And Maniac I., Theodore E. Smart

Electrical and Computer Engineering ETDs

The University of New Mexico has acquired two general purpose computers; a CRC-102A and MANIAC I. The MANIAC I has been installed and is nearing operational status, while the CRC-102A has been in use for some time. When both computers are operating it will be desirable, in certain, cases, to program a problem for both. A means for translating a program for one of the machines into a program for the other with a minimum of manual effort would, therefore, be useful. The purpose of this project was to translate the commands for one computer into commands for the other …

The Use Of Ferrophosphorous And Manganese Ore In High Density Concrete For Radiation Shieding, Robert A. Crist Jr.

Civil Engineering ETDs

The scope of this thesis encompasses the investigation of the feasibilities of using a locally and/or readily available heavy aggregate for high density concrete. Such an aggregate was found to be available in Socorro, New Mexico. The Socorro Manganese Corporation has a stockpile of over 7,000 tons of high-grade manganese ore (specific gravity = 4.5) potentially suitable as a heavy aggregate, and some of which was used for this research. Along with the manganese ore was used ferrophosphorous, a very heavy aggregate manufacture by the Victor Chemical Works (specific gravity = 6.5), to obtain a range of densities that would …

Theory And Fabrication Of Point Contact Diodes Utilizing Reduced Single Crystal Rutile Tio2, Goebel Davis Jr.

Electrical and Computer Engineering ETDs

Single Crystal Rutile TiO2 upon reduction by heating in an atmosphere of hydrogen becomes a semiconductor, and the conductivity increases with the time and temperature of reduction. The reduction process creates oxygen vacancies with which there are associated two loosely bound electrons. These electrons may be raised to the conduction band by thermal excitation. Hence, an oxygen vacancy behaves like an impurity donor site.

The Control And Measurement Of Minute Curvatures In A Steel Shaft, Donald F. Wilkes

Mechanical Engineering ETDs

The primary purpose of this thesis was the solution of several special problems relating to the establishment, adjustment, and measurement of small elastic curvatures and the associated strains in a metal shaft. The solution of these problems was an important link in the development of a new type of seismometer for measuring extremely long periods with vibrations (up to 60 seconds). To achieve the sensitivity and long natural period of vibration required for accurate measurements of long-period waves, the seismometer employs a seismic mass which is suspended on an air film and constrained to follow an essentially horizontal guide rod. …

The Control And Measurement Of Minute Curvatures In A Steel Shaft, Donald F. Wilkes

Mechanical Engineering ETDs

The primary purpose of this thesis was the solution of several special problems relating to the establishment, adjustment, and measurement of small elastic curvatures and the associated strains in a metal shaft. The solution of these problems was an important link in the development of a new type of seismometer for measuring extremely long period with vibrations (up to 60 seconds). To achieve the sensitivity and long natural period of vibration required for accurate measurements of long-period waves, the seismometer employs a seismic mass which is suspended on an air film and constrained to follow an essentially horizontal guide rod. …

The Use Of Compensation With Directional Couplers, Roland Alan Lincoln

Electrical and Computer Engineering ETDs

This thesis describes an improved technique for measuring voltage standing wave ratio (VSWR). The reflectometer system is analyzed, and an improved coaxial system is presented which more accurately measures VSWR.

Computer Programs For Determining Radar Return Power And Fading Spectra, Chung Chia

Electrical and Computer Engineering ETDs

The properties of radar terrain return at near vertical incidence have been under investigation at the University of New Mexico with Sandia Corporation, Albuquerque, New Mexico, and the United States Naval Ordinance Test Station, China Lake, California.

Correlation Of The Atterberg Limits And The California Bearing Ratio Values For Soil-Cement Media, Vernon E. Kerr

Civil Engineering ETDs

Tests were made on three different soils, using controlled amounts of Portland cement and water. All tests were made using a standard liquid limit device or a six-inch mold. The variables were amounts of Portland cement, degree and thoroughness of mixing, moisture content, curing and compaction of samples. The recommended procedures for performing the Plastic Limits Test, Liquid Limits Test and the California Bearing Ratio Test were followed with very few exceptions. All values obtained from testing are entered in the report and no retesting was done.

Mix Design Study And Compressive Strengths Obtainable From Pumice-Aggregate Concrete, Benjamin F. Snow

Civil Engineering ETDs

Compressive strengths of pumice-aggregate concrete were examined by introducing controlled variables into the mix proportions. A mix design method is presented, and this method was analyzed for consistency and feasibility.

Transient Sensitivity Of Piezoelectric Accelerometers, William E. Baker

Electrical and Computer Engineering ETDs

No abstract provided.

Experimental Determination Of Dynamic Stress Concentration Factors In Rectangular Steel Bars, Jerome E. Ligocki

Civil Engineering ETDs

Stress concentration factors obtained from impact tests indicate substantial agreement with experimentally derived static stress concentration factors. Testing was limited to one 3/8 diameter centrally located hole in a long rectangular bar 2 inches wide. The hole was located at a bar cross section where a plane wave was found to exist. Stress pulse lengths as short as 50 microseconds duration was used in the experiments.

The experimental results confirm the ability of the resistance strength gage to accurately measure stress pulses. The proper amplitude response of the gage is proven by comparison with dynamic and static test results. The …

Design Of Crystal Filters, Charles E. Schmidt

Electrical and Computer Engineering ETDs

This thesis concerns the application of electromechanical impedance elements to electric wave filters, so it is appropriate to begin with some discussion of such elements. The most important type is the piezoelectric resonator, most commonly made quartz.