Engineering Commons^™

Molecular Size Distributions Of Heavy Metals In Lake Washington, William B. Andrews

Retrospective Theses and Dissertations

Four untreated and one magnesium treated water samples from Lake Washington, the potable water source for the city of Melbourne, Florida, were collected and analyzed for As, Cd, Cr, Cu, Fe, Pb, Ni, Zn, Mb, Ca, and color on the basis of molecular weight distribution. Molecular weight distributions of the samples were obtained using a Millipore ultrafiltration system and filters in the following sizes: 106, 105, 2.5 x 104, 104, and 103 nominal molecular weight limits (nmwl). Color causing materials in the untreated samples were found to be located in the molecular weight fraction greater than 2.5 x 104 nmwl. …

Performance Theorems For The Resource Scheduling Functions Of A Multiprocessing System, George Arthur Nicol

Dissertations and Theses

In this dissertation, a multiprocess scheduling model is developed and a set of performance theorems is constructed for the set of scheduling functions associated with the model. Each theorem describes the conditions under which a scheduling function exhibits a particular type of performance.

A Study Of The Effect Of Vibration On The Residual Stresses In A Welded Fabricated Tube, Shantini Ratnathicam

Dissertations and Theses

In many instances the predominant factor contributing to structural failure in welded parts is the residual stress which exists before the part is put into service. In this investigation an attempt is made to study the changes in residual stresses caused by vibrational stress relief (VSR). VSR is a fairly new idea in stress relief and there is no substantial evidence of its success in reducing residual stresses. This thesis documents the residual stress distributions found in 5/16 inch thick, 22 inch diameter welded fabricated tubes after VSR.

Molybdenum Stability In Coal Slags At 1400⁰C: Corrosion Properties For Mhd Electrode Applications., Kenton Brian Wright

Masters Theses

"Molten coal slag corrosion studies conducted on molybdenum at 1400°C used static and stirred slag experiments and electrical current experiments to parallel electrode conditions of slagging duct MHD generators. Crucibles containing molybdenum and slag were exposed to combustion-type gases in a tube furnace. Carbon monoxide-carbon dioxide gas mixtures controlled oxygen partial pressures at selected values between 10^-11 and 10^-3 atm. Metallograph and microprobe examination of polished sample sections defined corrosion characteristics.

At 1400°C, molybdenum metal is stable below 10^-9 atm oxygen pressure. Molybdenum dioxide is stable at higher pressure, but volatile molybdenum trioxides prevent formation of stable …

Processing Of Copper Refinery Anode Slimes, Shrirang Anant Kulkarni

Masters Theses

"A study of commercial copper refinery anode slimes has been conducted to evaluate the separation of valuable metals contained in the slimes. The slimes contain substantial quantities of Ag, Sn, Au, Pb, and Cu. The values were present principally as AgCl, SnO₂, Au, PbSO₄, Cu and CuSO₄.

A Roast-Leach-Roast-Leach (RLRL) technique solubilized up to 91 pct of the Ag and 99 pct of the Cu from raw slimes.

The Pb-Sn separation was investigated using the following hydrometallurgical techniques: 1) DETA (diethylene triamine) leaching; 2) NaOH leaching; 3) (NH₄)₂CO₃ leaching; …

Stress-Strain Properties Of Compacted Modified Memphis Loess, Danny Lloyd Kerns

Masters Theses

"A study was made of the stress-strain characteristics of compacted samples of a modified loessial soil obtained near Memphis, Tennessee. The study consisted of compacting samples at a constant water content and at unit weights of 92, 96 and 100 pounds per cubic foot (1470, 1540 and 1600 kg/m³). Triaxial tests were performed on unsaturated compacted specimens to obtain stress-strain-volume change data. These data were used to determine stress-dependent functions for tangent modulus and Poisson's ratio"--Abstract, page ii.

Phase Equilibria In Aqueous Magnesium Chloride, Sulfate, Chromate And Phosphate Systems, Ladawan Urwongse

Doctoral Dissertations

"In the first part of the present study, which is presented in Paper I, solubility of MgO in aqueous HCl solutions at 23° ± 3°C was measured and combined with analyses of neat magnesium oxychloride cements to construct an equilibrium phase diagram for the system MgO-MgCl₂-H₂O. Invariant liquids in equilibrium with Mg(OH)₂ and 5Mg(OH)₂·MgCl₂·8H₂O (5.1.8), with 5·1·8 and 3Mg(OH)₂·MgCl₂·8H₂O (3·1·8), and with 3·1·8 and MgCl₂·6H₂O were located at 0.8 ± 0.2 MgO, 17.0 ±0.5 MgCl₂; at 1.0 …

Photogrammetric Digitizing System, Frank Richard Gorshe

Dissertations and Theses

The acquisition of terrain data from aerial photography using digital photogrammetric methods gives the engineer and planner an economical alternative to conventional ground surveys. This paper describes a complete photogrammetric digitizing system developed for the Portland District Army Corps of Engineers. The hardware of the system consists of a

Wild AlO first order stereoplotter interfaced to an Altec AC-74 coordinate digitizer which is interfaced to both a Hewlett Packard 9810A programmable calculator and a Digi-Data nine-track magnetic tape recorder. The software of the system consists of photogrammetric routines developed for online computation by the programmable calculator and a sophisticated FORTRAN …

The Effects Of A Kinesthetic Training Program On The Acquisition Of Industrial Skills Among University Students, John V. Mockler

Dissertations and Theses @ UNI

Training workers for specific jobs is receiving much attention in industry. The demand for skilled workers is increasing constantly and as this happens newer and more efficient methods of training are sought In the psychomotor/sensory area. skills that appear to offer a wide amount of transferability are those dealing with fine sensitivity, manual dexterity, and coordination. Even though these skills lend themselves well to training, this area is somewhat deficient in current educational and training programs (Sjogren, 1977, p.23). Presently, on-the-job training is widely used for training workers in the actual tasks they will perform during their job.

The process …

The Relationship Between Teacher Sex Role Models And Career Aspirations Of High School Industrial Arts Students, Janet Lynn Robb

Dissertations and Theses @ UNI

Sex role stereotyping has been the focus of a number of research projects trying to determine just where stereotyping lies and ways to eliminate it. Although most of the research points toward role modeling as a major cause, little has been done to test that theory.

The purpose of this study was to determine the relationship between teacher sex role models and the career aspirations of students enrolled in high school industrial arts courses throughout the United States. This study was limited to tenth, eleventh, and twelfth grade students enrolled in industrial arts programs in high schools in the United …

An Instrument For Determination Of The Polarization Of Fluorescence, George Irwin Johnston

Dissertations and Theses

This thesis is concerned with the development of a compact, sensitive and reliable instrument for determination of the polarization of fluorescence of fluorescein tagged molecules in solution. The instrument as designed and constructed differs from others (2,3,4,5,6,8,9). The difference is that all of its optical system is aligned on a single axis. This was accomplished by the use of an ellipsoidal mirror positioned between the excitation source and the phototube fluorescence signal receiver. In addition, the excitation source, a 45 watt tungsten-iodide light was electronically regulated to control the intensity.

Two types of determinations were made to verify the performance …

Complete Elastic-Plastic Solution Around A Tensile Crack In Strain-Hardening Materials, Clancy Hatleberg

Mechanical Engineering ETDs

A complete elastic-plastic solution for both small and large scale yielding is found for the total stress field surrounding a tensile crack in an infinite sheet of strain-hardening materials under conditions of plane stress. The solution is based on the deformation theory of plasticity in conjunction with strain-hardening stress-strain relations, and is found by using the minimum of a modified complimentary energy principle coupled with a modified Ritz method. Numerical results are obtained for two approximate constitutive laws; a Ramberg-Osgood stress-strain relation and a modified Ramberg-Osgood stress-strain relation. Results indicate that the total stresses are discontinuous as the crack tip …

The Effect Of Volatile Fission Products On Fuel Motion In Nuclear Fuel Elements, Paul Sasa

Nuclear Engineering ETDs

Stringent licensing procedures for commercial nuclear reactor operation require an in-depth analysis of the phenomena associated with postulated reactor core overheating accidents. One aspect of nuclear reactor safety assessment is a prediction of fuel behavior associated with such postulated overheating events, which includes an assessment of the role of fission product inventory contained within irradiated fuel elements on fuel relocation potential. In general the gaseous fission product, such as Xenon and Krypton, have been considered the most likely candidates for fuel relocation due to gas dissolution from the fuel matrix and bubble expansion during fuel overheating; thus, such gaseous fission …

Real-Time Estimation Of Aerodynamic Coefficients By Means Of An Extended Kalman Filter, James Robert Kelsey

Electrical and Computer Engineering ETDs

A technique for estimation of the aerodynamic parameters of a flight vehicle from onboard measurements is presented.

An extended Kalman filter is used to extract the parameters in the presence of measurement noise and initial uncertainty of the parameter values. Computer generated data were used for the measurement information in lieu of actual flight data.

Several state models of varying complexity are studied in an attempt to find a model which yields adequate estimates while minimizing the required computation time.

A Study Of A Wind Tunnel Measurement System For Unsteady Pressures Using Pneumatic Transmission Lines, Mohammed Javed Khan

Theses and Dissertations

The application of pneumatic transmission lines theory to a tube-scanning valve system for unsteady pressure measurements in the AFIT 5-foot wind tunnel is investigated. Transfer gains of various tube-scanning valve configurations were experimentally measured and the validity of a theoretical model verified for a frequency range of 20 Hz to 140 Hz. The selected system having a 0.0625-in. ID flexible tube of 84 in. length connected to a scanning valve was installed in the wind tunnel. Unsteady pressures introduced over an 18 percent airfoil at zero angle of attack were measured with this system. Data were collected for 0, 40, …

The Evaluation Of Corrosion Inhibitors For Controlling Corrosion In Closed Paper Mill White Water Systems, Ifeanyi E. C. Okeke

Masters Theses

No abstract provided.

Effect Of Concentration And Ph On Parametric Pumping Separations, Tsu-Kun S. Hsieh

Theses

The technique of parametric pumping represents a new and valuable development in the separation science of proteins. Many conventional protein separation are often processed batchwise. However, parametric pumping offers the possibility of continuous processing; the continuous process provides both the advantages of decreasing the processing time and of minimizing degradation.

Preliminary step testing experiments were conducted to study the equilibrium of protein between the stationary and mobile phase of the sephadex ion exchanger.

It was the purpose of this research to study the feasibility of operating a semi-continuous parametric pump with a sephadex ion exchanger for the separation of a …

Concentrated Organic Separations By The Cyclic Indirect Freezing Process, Jeffrey Carl Miles

Chemical and Biological Engineering ETDs

This study demonstrates the technical feasibility of purifying concentrated organic solutions by the cyclic indirect freezing process with in-situ washing and in-situ melting operations. The key to a successful purification in the freezing process is a near plug flow displacement of unfrozen liquor from the bed in an in-situ washing operation. To be successful, a freezing step has to be initiated uniformly and a high permeability bed has to be formed uniformly throughout the freezing conduits. In the study, a nucleation technique based on pressure induced supersaturation has been used to accomplish a uniform initiation and a pressure induced freezing …

Phosphorus Content And Release From Lake Sediments By Agitation, Hsien Ping Tang

Retrospective Theses and Dissertations

Man-made mixing in shallow lakes will resuspend bottom sediments and increase phosphorus concentration in the water body. The increase in phosphorus content may affect the lake productivity. During the course of this study, a better understanding of the water-sediment-phosphorus relationships of some shallow lakes in Central Florida was attempted. Column studies and batch experiments were used to investigate the effect of mechanical mixing on the release of phosphorus from bottom sediments collected from Lake Claire and Jessup. The particle size distribution and density distribution of the bottom sediments were studied and the release of phosphorus from each fraction was measured. …

Speech Synthesis Utilizing Microcomputer Control, Joseph N. Uzel

Retrospective Theses and Dissertations

This report explores the subject of speech synthesis. Information given includes a brief explanation of speech production in man, an historical view of speech synthesis, and four types of electronic synthesizers in use today. Also included is a brief presentation on phonetics, the study of speech sounds. An understanding of this subject is necessary to see how a synthesizer must produce certain sounds, and how these sounds are put together to create words. Finally a description of a limited text speech synthesizer is presented. This system allows the user to enter English text via a keyboard and have it output …

The Design And Analysis Of A Unique Broadband Underwater Acoustic Source, Allan Mark Young

Retrospective Theses and Dissertations

Requirements exist for a unique type of underwater acoustic source. The transducer is in the form of a linear array of discrete elements and is required to have a constants transmitting voltage response and carefully controlled directivity characteristics over a two octave bandwidth. A generalized model of a linear array of cylindrical piezoelectric ceramic acoustic radiators is developed and applied to the design of a prototype which operates over approximately one half of the required bandwidth. The prototype transducer was built and the measured results are compared with those predicted by the model. Recommendations are made for improving the performance …

An Analysis Of The Effect Of Vibration Sensitivity On Hydrophone Design, George Dickson Hugus

Retrospective Theses and Dissertations

Hydrophones used in the ocean produce spurious outputs due to vibration sensitivity which can severely degrade measurement accuracy. Sources of these vibration inputs are ocean surface waves, flow turbulence, and induced mechanical vibration. The hydrophone response to these vibrations is a noise voltage output. This can leave to a signal-to-noise problem particularly when measurements of small sound pressure levels are to be made. The objective of this thesis is to analyze the vibration response of three typical piezoelectric hydrophone sensor elements configurations and give design methods and constraints for reducing the problem of vibration sensitivity to an acceptable level. The …

Effect Of Precursor Heating On Radiating And Chemically Reacting Viscous Flow Around A Jovian Entry Body, Kuo Yen Szema

Mechanical & Aerospace Engineering Theses & Dissertations

The influence of changes in the precursor region flow properties (resulting from absorption of the radiation from the shock layer) on the entire shock layer flow phenomena around a Jovian entry body is investigated under physically realistic conditions. In the precursor region, the flow is considered to be inviscid and the variations in flow properties are determined by employing the small perturbation technique as well as the thin layer approximation. The flow in the shock layer is assumed to be steady, axisymmetric and viscous. The analysis is carried out by considering both the chemical equilibrium and nonequilibrium composition of the …

Interaction Between Structures And Fluids, Rahim Falsafi-Haghighi

Dissertations

A finite element model for the study of solid-fluid interaction, with applications in flow-induced vibration analysis of reactor vessel and heat exchanger internals, is presented. The model is based on the discretization of the solid equation of motion and the fluid continuity and momentum equations and employs the solid displacements together with the fluid pressure and velocity components as the nodal degrees of freedom. This permits a realistic and accurate implementation of boundary conditions, in contrast with methods using solid displacements and fluid pressure as the only field variables. The numerical solution of the resulting matrix equation, involving non-symetric matrices, …

The Measurement Of Depolarized Radiation For Monitoring The Mass Concentration Of Particulates, Bruce E. Wilson

Theses

The depolarization of backscattered polarized incident radiation which is expressed as a depolarization ratio was investigated as a means of monitoring the mass concentration of particles in stacks from coal-fired burners. This involved the design of an instrument that would detect small levels of radiation. Two methods were investigated. The first utilized a Gallium Arsenide laser and a silicon detector diode; the second was composed of a xenon flash lamp and a photomultiplier detector tube.

The relationship between the depolarization ratio and the mass concentration of diamond particles in the 0.01 gm/m³ to 0.5 gm/m³ was determined. Diamond …

Ocean Thermal Energy Conversion By Using A Solidification Melting Cycle, Wen Liang Lin

Chemical and Biological Engineering ETDs

An OTEC (Ocean Thermal Energy Conversion) power plant uses warm surface seawater (24° C - 28° C) as a heat source and deep cold seawater (4° C - 7°C) as a heat sink. With this temperature difference, a heat engine which delivers either mechanical or electric power can be con­structed. There are some limitations and problems of evaporators and condensers to be used in a closed Rankine cycle OTEC plant which have seriously limited the applicability of this concept. This study proposed a process using the S/L engine---a heat engine that utilizes a working medium undergoing solidification and melting operations. …

Surface Roughness Effects In Hydrodynamic Lubrication, Johnny Lynn Teale

Mechanical Engineering ETDs

Prediction of pressure and leakage in a hydrodynamic bearing when surface roughness effects are important is an essential step in bearing design. The inclusion of surface roughness effects in bearing analysis allows more accurate prediction of bearing life. It has been shown that the average flow model developed by Cheng and Patir is a promising technique for determining surface roughness effects. The objective of this investigation is to examine the validity, applicability and limitation of the average flow model. Validity of the average flow model is ascertained by checking the independence of flow factors. Discussion of the general Reynolds equation …

A System For Detecting Neutrons In The Harsh Radiation Environment Of A Relativistic Electron Beam, Lyle Wayne Kruse

Nuclear Engineering ETDs

Newly developed detectors and procedures allow measurement of neutron yield and energy in the harsh radiation environment of a relativistic electron beam source. A new photomultiplier tube design and special gating methods provide the basis for novel time-of-flight and total-yield detectors. The technique of activation analysis is expanded to provide a neutron energy spectrometer. There is a demonstrated potential in the use of the integrated system as a valuable diagnostic tool to study particle-beam fusion, intense ion-beam interactions, and pulsed neutron sources for simulating weapons effects. A physical lower limit of 10⁸ neutrons into 4π is established for accurate …

Fuzzy Probability And Probabilistic Processes, Abraham Kandel

Electrical and Computer Engineering ETDs

In this dissertation, contributions to fuzzy probability and to differential equations with fuzzy parameters are made.

After an introductory chapter, a review of fuzzy sets and fuzzy algebra is given in Chapter 2. The main new results of the dissertation are contained in Chapter 3.

In Chapter 3, Zadeh's definition of the probability of a "fuzzy event" and "the event" and "the average value of a fuzzy function" are extended into the time domain. It is then shown that not only grades of membership, but also probabilistic processes with notions of fuzziness contained, can be defined which obey ordinary, matric, …

Second And Third Generation Vector Computers And Their Fortran Processors, Kay Anderson Hansborough

Electrical and Computer Engineering ETDs

SECOND AND THIRD GENERATION VECTOR COMPUTERS AND THEIR

FORTRAN PROCESSORS

Kay Anderson Hansborough, M.S.

Department of Electrical Engineering and Computer Science

The University of New Mexico, 1976

This work describes the architectures of five large vector computers. These computers are the CDC 7600, CDC STAR-100, TI Advanced Scientific Computer, CRAY-1, and Burroughs Scientific Processor.

Then the FORTRAN languages and their vector extensions are described for each machine. In addition to these languages, the IBM VECTRAN language is described.