Engineering Commons^™

A Measurement Of Complex Viscosity With Large Amplitudes, Kuo-Shein Shen

Doctoral Dissertations

"In order to study the viscoelastic properties of polymer solutions and greases, a dynamic apparatus was built for making measurements of complex viscosity. Characteristic impedance was measured by a force transducer, an accelerometer and a phase meter. Large amplitudes to 0.5 inch can be obtained with this apparatus. The largest amplitude used was 1.27 x10⁻¹ cm. The frequency range was 30 Hz - 1500Hz. The lowest dynamic viscosity to be measured was 0.5 poise. In order to determine the capabilities of the instrument, complex viscosities of polymer solutions and greases were measured. The polymer solutions studied were polyisobutylene (PIB) L-80, …

Internal Friction Of Ion Exchanged Li₂O•Al₂O₃•2sio₂ Glasses, A. Ismail A. Abdel-Latif

Doctoral Dissertations

"Li₂O•Al₂O₂•2SiO₂ glass fibers were ion-exchanged from 1 to 300 minutes in a sodium nitrate bath at 366ºC. The internal friction was measured along with the lithium and sodium concentration profiles. As sodium progressively replaced lithium, the alkali internal friction peak became smaller while a new peak (mixed alkali peak) appeared and increased in magnitude. These changes in the internal friction are similar to those that occur upon the addition of a second alkali to glasses prepared by conventional melting. The magnitude of both internal friction peaks in ion exchanged glasses was dependent on the overall glass composition. The magnitude of …

Dynamic Behavior Of Eccentrically Stiffened Plates, Charles Stuart Ferrell

Doctoral Dissertations

"The dynamic behavior of eccentrically stiffened rectangular plates is studied by the finite element method. The addition of stiffeners to a plate structure is a common method of increasing the rigidity of the structure with a minimum of weight increase. However, this stiffened plate configuration does not easily lend itself to analysis. This study is an approach to finding a rational method by which the dynamic behavior of such a stiffened plate structure may be determined. The governing differential equations for the finite element model are derived and the stiffness and mass matrices for the plate and stiffener elements are …

Statistical Study Of Rock Drilling By Hypervelocity Jets From Explosive Shaped Charges, John William Brown

Doctoral Dissertations

"The drilling effect in rock of hypervelocity jets from explosive shaped charges was investigated experimentally to supplement a rapid excavation concept. The effects of the design factors of the charge and the mechanical properties of eight rock types were studied. Experiments were both designed and analyzed upon statistical principles. A full factorial experimental design was used for each of seven rock types. An analysis of variance and the k-ratio least significant-difference test were applied to the results.

The optimum design of shaped charges for drilling was found to be independent of rock type and rock properties. For composition C-4 charges …

Identification Of Linear Systems With Delay Via A Learning Model, Hugh Francis Spence

Doctoral Dissertations

"The effects of input delay on an identification scheme using a learning model are investigated. The parameter adjustment laws for the learning model are derived through Lyapunov methods similar to those used for the model reference adaptive control systems of Parks. For no measurement noise or delay mismatch between the learning model and system, the parameters are adjusted to bring the error between model and plant to zero. When there is delay mismatch between the inputs of the learning model and the unknown system, the convergence of the parameters of the learning model to those of the unknown system is …

Surface Reactions Of Boron With Clean Tungsten Substrates, Thomas A. Flaim

Doctoral Dissertations

"A model developed to predict adsorbate-induced work-function changes for thermionic emitters is shown here to apply to a more general class of electron emission phenomena and a much broader range of adsorbates. This model predicts that chemically, vapor-deposited boron will increase the work function of a clean tungsten substrate at coverages between 0 and 1 monolayer. This is the first time that a single model has been shown to predict both positive and negative work function changes for different adsorbates. The reactions of chemically, vapor-deposited (CVD) boron with clean tungsten substrates were studied using field emission microscopy (FEM) and low …

A Comparative Study Of Experimental And Computed Compressibility Factors Of Methane - Nitrogen - Helium System, Promod Kumar Taneja

Masters Theses

"The volumetric data for methane, nitrogen, and helium mixtures have been determined experimentally at low temperatures (60ºF to -30ºF) over a pressure range of 1000 to 5000 psig. An attempt has been made to show that the extension of standard techniques viz, "The Law of Corresponding States" for predicting the compressibility factors of pure hydrocarbons and hydrocarbon mixtures is not adequate for mixtures containing even very small amounts of helium. The deviation from the computed compressibility factors is found to be maximum at low temperatures and high pressures (up to 22%) for the mixtures studied"--Abstract, page ii.

Synthesis Of Active Distributed Rc Networks Via The W=E[Superscript Square Root Of S] Transmission, Roy Dale Hensley

Masters Theses

"The material presented here provides a means for synthesis of networks containing uniformly distributed RC elements. After transforming the desired transfer function into a function rational in W = e[superscript square root of sRC] , state-variable synthesis methods are applied to obtain a model containing elements with transfer functions of the form 1/W. A circuit is then presented for the 1/W block along with error analysis and design procedures for use in construction of the model. The elements of the synthesis procedures of Wyndrum and O'Shea are presented for comparison. Furthermore, synthesis of functions rational in W and Θ = …

A Study Of A Nitrogen Heat Pipe, Jay Dudheker

Masters Theses

"An experimental heat pipe, 33.25 inches long and 0.75 inches in diameter, with modacrylic fiber wick and liquid nitrogen as its working fluid was constructed to study the operating characteristics of a cryogenic heat pipe. The effective thermal conductivity and the axial temperature distribution were determined for various levels of power input. The effect of inclination angle on the above parameters was also measured"--Abstract, page ii.

Development Of A Set Of Optimum Synchronization Codes For A Unique Decoder Mechanization, Irv D. Siegel

Masters Theses

"Synchronization requirements are specified for and a unique decoder mechanization is associated with a particular communication system. Optimum synchronization codes, defined as codes which are the least susceptible to false synchronization indications, are sought. Existing sets of optimum codes are investigated for applicability. This Thesis shows how these sets were developed from selected criteria and demonstrates why their theoretical nature produces unsatisfactory results in the present application wherein all parameters are known. A computer program was written to examine code pattern performance in the specified decoder under actual operating conditions. From an analysis of the results, a recommended set of …

The Design Of A Data Set Interface, Wayne Everett Omohundro

Masters Theses

"This paper describes the data set interface which connects the SCC-650 digital computer to the IBM-360 computer by means of a data communications link over a telephone line. To provide the necessary background information, the basic concepts and techniques of digital data communications are discussed. In conjunction with these concepts, several possible system arrangements of modems, terminals, and computers are given. Also two computer-to-computer networks are discussed. The first one is the system used at the Lawrence Radiation Laboratory for the acquisition of experimental data. The second system, the one in which the interface operates, is the data communications system …

The Effect Of Diameter On The Film Boiling Behavior Of Liquid Nitrogen, William Joseph Wafer

Masters Theses

"A film boiling heat transfer study was conducted for liquid nitrogen at atmospheric pressure. The heat transfer surfaces used were cylinders with outside diameters of 0.450, 0.650, 0.850, and 1.000 inches. The temperature differences covered were from approximately 150ºF to approximately 600ºF. The data indicate that the heat flux will decrease to a minimum then increase slightly as the diameter of the heat transfer element is increased at constant temperature difference. The heat transfer coefficient is expected to approach a flat plate correlation as the diameter approaches infinity"--Abstract, page ii.

A Triangular Element For Numerical Solutions Of Axisymmetric Conduction Problems In Cylindrical Coordinates, Prafulla Chandra Mahata

Masters Theses

"The triangular element is one of the many suitable elements which are used in finite difference methods as applied to conduction heat transfer. Such elements find many applications in conduction problems in Cartesian coordinates. This work proposes a new triangular element for axisymmetric conduction problems in cylindrical coordinates. The validity and workability of the networks formed by the proposed triangular elements are strengthened by selected examples. The work is completed by the application of the triangular element to an industrial problem having irregular boundaries. The results are compared with the solution obtained by the finite element method"--Abstract, page ii.

Evaluation Of A Cation Isotopic Substitution Technique In Conjunction With A High Temperature Gas Pycnometer For Determining The Stoichiometry Of Materials, Michael Clair Graves

Masters Theses

"This study was concerned with the evaluation of a high temperature gas pycnometer, used in conjunction with a cation isotopic substitution technique, for determining the stoichiometry of materials. Three methods were investigated for determining the correction factors for the thermal gradient effects in the gas pycnometer. The correction factors were shown to be dependent on the temperature, the sample volume, and the height of the sample in the sample chamber. Under the conditions of these experiments, the correction factors were shown to be essentially independent of sample grain size and pycnometer atmosphere. The determination of the stoichiometry of cadmium oxide …

Some Factors Affecting The Results In Cyclic Triaxial Tests, Suresh Kumar Chaudhary

Masters Theses

"A major cause of damage to structures and earth embankments during earthquakes or any other such dynamic vibrating loading conditions has been the liquefaction of saturated sands. There have been several investigations to establish a convenient and relatively simple laboratory test procedure and to study the nature of field conditions leading to sand liquefaction. This investigation evaluates the effects of sample size, testing frequency, and the method of sample preparation on the number of cycles to cause initial liquefaction in pulsating triaxial tests using standardized equipment and test procedures. It has been found that sample size does affect test results …

Comparing Community Resources To Industrial Needs With Application To Daviess County, Missouri, Jay Eldon Waggoner Jr.

Masters Theses

"A method of matching industries with communities, the modified Miller-Weiss Indugram, is developed. The technique compares the environmental needs of industry with the environmental resources of a community. The comparison is based upon twenty-five environmental factors. Application of the technique is made to Daviess County, Missouri. Results indicate those industries which are best suited for this rural area"--Abstract, page ii.

Normal Mode Method Applied To The Transient Longitudinal Vibrations Of A Finite Rod With Material Damping And Viscoelastic Dispersion, David Arthur Levene

Masters Theses

"Longitudinal vibrations of a finite rod with material damping and frequency dependent material properties are examined. The normal mode method is used to investigate the transient response of a rod which is free to move in the longitudinal direction and is subjected to a transient longitudinal loading condition at one end. The equations of motion are derived and solved using both the differential equations approach and the energy methods approach of the normal mode method. The effects of material damping and frequency dependent material properties are considered by formulating the stress-strain relation for the material such that the modulus of …

The Design Of A Lightning Data Interface, Larry Lee Hosto

Masters Theses

"A system for the processing of lightning stroke location data has been designed. The system will be used for studying the correlation of lightning and thunderstorm precipitation. The lightning stroke location system has been developed to gain further information about the cause-effect relationship between lightning stroke activity and thunderstorm precipitation. The system will consist of an analog computational network to find the tangent of the azimuth of the lightning stroke, an analog-to-digital converter, and a computer program which will process and store data on magnetic tape. This paper will discuss the design of the analog computational network and the computer …

The Effect Of 15% Mno On The Phase Relations In The System Cao-Feo-Sio₂ At 1450ºc, Aquil Ahmad

Masters Theses

"A study was made of the phase relations at 1450ºC in the systems CaO-FeO-SiO₂ and CaO-FeO-SiO₂ -15% MnO, in equilibrium with metallic iron. The stability region of different phases was determined by microscopic examination and electron-beam microprobe analysis of the quenched specimens. The effect of 15% MnO on the liquid saturation boundary of the system CaO-(FeO+MnO)-SiO₂ was discussed in terms of the effect of MnO on slag making reactions in the Basic Oxygen Furnace steelmaking process"--Abstract, page ii.

The Influence Of Temperature, Carbon Content, And Preloading On Secondary Consolidation Of A Clay, Richard Kai-Ming So

Masters Theses

"The effect of temperature, organic carbon content, and preloading on secondary consolidation of Bryce clay has been studied. A straight line plot of void ratio versus logarithm of time was established in secondary consolidation for long term loading periods up to one month. Temperature changes within the range of 5ºC. to 45ºC. were studied in the secondary consolidation phase at different stress levels and different carbon contents of the soil. Secondary consolidation in a preloading cycle at a stress level of 2 tsf unloaded to 1 tsf and reloaded to 2 tsf was studied. The preloading tests were at temperatures …

An Experimental Determination Of The Effect Of The Axisymmetric Turbulent Wake On The Pressure Distribution On A Sphere, Martin Gardner Bowin

Masters Theses

"A study of the effect of the turbulent wake of a water drop on the motion of a smaller droplet is essential in order to gain an understanding of the behavior associated with the collision coalescence phenomena. The use of spheres of macroscopic size proves to be a valuable method in observing these effects. This experimental investigation centers on (1) a check on the validity of the instrumented sphere as a device to measure normal static pressure, and (2) the study of the effect of the turbulent wake of the test model sphere upon the instrumented sphere. Measurements were made …

Irradiation Enhanced Decomposition Of A Nickel-Carbon Solid Solution, Bryce Linn Shriver

Masters Theses

"This investigation was performed to determine the effects of room temperature neutron irradiation on the distribution of carbon in a nickel--0.3 wt. % carbon alloy. The experiment consisted of comparing the amount of carbon in solid solution and the internal stresses of both unirradiated and irradiated (10¹³ fn-cm⁻² < Φ_F < 10¹⁸ fn-cm⁻²) samples following isochronal anneals between 100ºC and 1200ºC by using the magnetic disaccommodation technique. The results indicate that the amount of carbon remaining in solid solution decreases with increasing neutron dose. At temperatures below 200ºC this is due to the trapping of carbon by mobile irradiation-produced defects. Between 200ºC and 600ºC the formation of metastable carbides is enhanced by the presence of irradiation-produced defects. No differences are observed in irradiated and unirradiated samples above 600ºC"--Abstract, page iii.

Triangular Signal Stabilization Of Nonlinear Systems, Kamaleddin Yadavar Nikravesh

Masters Theses

"Many nonlinear systems display self-sustained oscillations which are often undesirable. The stabilizing effect of a high frequency input signal on an oscillating system with one nonlinearity is determined by the characteristics of the nonlinear element in the system, the linear portion of the system and the amplitude of the signal. This investigation has been concerned with the effect of a triangular wave stabilizing signal on these self oscillations. The equivalent gains for several common nonlinearities are derived. The pseudo describing function introduced by Oldenburger and Boyer for sinusoidal stabilization has been extended to the triangular wave case, and it is …

Phase Equilibrium And Thermodynamic Study Of Lime-Iron Oxide Solid Solutions, Shin Suk Kang

Masters Theses

"The solubility limits of iron oxide in solid lime were determined as a function of oxygen pressure at 1300º and 1400ºG in the system CaO-iron oxide. The stability region of dicalcium ferrite was determined with respect to formation of lime-iron oxide solid solution and liquid oxide. In addition, the hydration behavior in moist air of pure lime and sintered mixtures of lime and iron oxide was also observed. Pelletized samples were equilibrated under known oxygen partial pressures and quenched. Phases present in the quenched samples were identified by microscopy. The solubility limit of iron oxide in CaO is strongly dependent …

Quenching Defects In Aluminum Plus Ten Atomic Per Cent Zinc, James Thomas Grider

Masters Theses

"This study was undertaken to resolve the conflict which has recently arisen as to the as-quenched microstructure in the Al-Zn system as revealed by thin film transmission electron microscopy. The composition range of most active study has been that from 5 to 15 atomic per cent Zn in superpurity AL. Consequently a composition of 10 atomic per cent Zn was chosen for this study. There are no discontinuties in the phase diagram in this composition range which would influence the above choice. It exists as a single phase solid solution at high temperatures and as a two phase alloy at …

A Comprehensive Investigation Of The Behavior Of Saturated Sands Subjected To Cyclic Triaxial Loadings., James Francis Kanipe

Civil Engineering ETDs

Considerable interest in earthquake engineering has developed during the past decade. Due to the potential hazards involved in foundation failures of nuclear power plants, and because there is an increase in the demand for earth dams throughout the world together with a decrease in desirable sites, it has become imperative that reliable techniques be developed to predict the response of soils to earthquake induced forces. As an integral part of such an endeavor, this research program was directed toward the identification of the various factors which significantly influence the development of pore pressure in saturated sands subjected to cyclic stress …

Relationship Between Soil Support Value And Kentucky Cbr, Tommy C. Hopkins

Kentucky Transportation Center Research Report

Three slightly different correlations between Kentucky CBR's and the AASHO Road Test soil support values were developed. The first relationship was made by assuming a logarithmic scale between Kentucky CBR's of 5.2 and 100, which corresponded to values on the soil support scale of 3 and 10, respectively. The Kentucky CBR of 5.2 was determined by performing tests on the AASHO road subgrade soils. For practical purposes, the AASHO Road Test crushed stone base material was assumed to be a "100 percent CBR material" (this assumption was based on CBR data previously reported by Shook and Fang). The second correlation …

Statistical Quality Control Of Highway Construction And Materials, J. B. Venable

Kentucky Transportation Center Research Report

The objective of this report is to review existing local practices used in establishing and enforcing highway specifications and construction processes and to compare these practices. With procedures based on statistical quality control concepts. In order that statistical quality control concepts may be properly used where applicable, the first part of this report considers the general theory underlying the use of statistical control methods and the development of different types. Of acceptance plans which may be used in the highway construction industry. The second portion of the report is concerned with analyzing and comparing Kentucky's current specification requirements with typical …

Continuously Reinforced Concrete Pavement, James H. Havens

Kentucky Transportation Center Research Report

A sampling-type crack survey was made in July 1969; 200 feet in each 1000 feet were sampled. The average interval between cracks was 5.78 feet. Paving was completed in late 1968. The average crack interval in July 1970 was 4.14 feet. The 1970 survey was also a sampling type.

It is apparent that cracking approached maturity or equilibrium during the first year. Apparently, too, most of the cracking occurred during the first few weeks after construction – which suggests curing shrinkage as a contributory cause. A discussion of the significance of time and temperature will follow the presentation of other …

Evaluation Of Cored Specimens From Timber Caisson Beneath Pier No. 2 Of The Us 25 Bridge Over The Ohio River Between Covington And Cincinnati, James H. Havens, Assaf S. Rahal

Kentucky Transportation Center Research Report

Pier No. 2 of the former C&O Bridge at Covington is off-shore from the Kentucky side of the Ohio River. It was built in 1887. In 1927, this pier was extended downstream to support a new railroad bridge. The other three piers remained independent. The original structure was then converted to highway use and was purchased by the Commonwealth of Kentucky in 1937. In 1968, an engineering analysis of the superstructure indicated critical deficiencies in terms of "safety factors", and the bridge was closed to all traffic. Subsequently, various plans for reconstruction came under consideration. Of greatest significance here is …