Engineering Commons^™

Effects Of Multiple Scattering And Surface Albedo On The Photochemistry Of The Troposphere, Tommy Reinhold Robert Augustsson

Mechanical & Aerospace Engineering Theses & Dissertations

A one-dimensional photochemical model of the troposphere containing the species of the nitrogen, oxygen, carbon, hydrogen, and sulfur families has been developed and used to investigate the vertical profiles and the natural (including atmospheric chemical reactions) and anthropogenic sources and sinks of these species. The species continuity equations are solved numerically applying prescribed boundary conditions. The vertical flux is simulated by use of the parameterized eddy diffusion coefficients. Heterogeneous losses (e.g. rainout, gas-to-particle chemistry, and dry deposition), are parameterized to make calculated profiles consistent with measurements. The photochemical model is coupled to a radiative transfer model that calculates the radiation …

A Method Of Modeling Multirate Two-Dimensional Recursive Digital Filters Author, Albert P. Gerheim

Electrical & Computer Engineering Theses & Dissertations

This dissertation presents a method of modeling two dimensional sampled data systems with two sampling rates in each dimension. This methodology is applied to the problem of synthesizing two dimensional velocity filters using one dimensional prototypes and multirate concepts.

The modeling method includes the replacement of scalar z-transforms of signals by vectors of polynomials, and the replacement of scalar z-transforms of impulse responses by matrices of polynomials.

The synthesis of velocity filters is accomplished through the use of coordinate transformations in the z-transform domain which skew the ω₁ -ω₂ axes on the unit bidisc. The filters synthesized using …

Sound Absorption In N2-H2o Gas Mixtures At Room Temperature And Low Frequency/Pressure Ratios, William Axam Griffin

Mechanical & Aerospace Engineering Theses & Dissertations

This study was motivated by a need to obtain standard values of nitrogen's contribution to sound absorption in the Earth's atmosphere. Specific goals included accurate measurements of sound absorption in nitrogen - water vapor mixtures at room temperature and low frequency/pressure ratios, the determination of the N₂ vibrational relaxation peak location, (f/P)_max, on the f/P axis as a function of humidity, h, and critical evaluation of all results.

The free decay technique was used in a resonance tube to obtain ten sets of sound absorption data in N₂-H₂O gas mixtures and requisite companion …

Industrial Engineering Applications Using Microcomputers, Farid Guediri

Retrospective Theses and Dissertations

Five computer have been developed for practical use by Industrial Engineers in a production environment. The programs cover the areas of, forecasting, learning efficiency, production control, network analysis and optimum equipment replacement policies. Theory, complete program documentation and case example, for each program, are presented. Programs are written in an interactive Basic mode and have been tested on the Radio Shack TRS-8-0 and Apple II Plus systems.

Usage And Limitations Of Characteristic Vector Analysis Of Remote Sensing Multispectral Data For The Identification And Quantification Of Water Quality Parameters, Theodore A. Talay

Civil & Environmental Engineering Theses & Dissertations

Recent applications of the technique of characteristic vector analysis to remote-sensing water color data has met with varying degrees of success. It is apparent from these experiments that a more thorough understanding of the informational capability of characteristic vector analysis is needed.

Recycling Of Aluminium, Nayera Abdel Mossawer Shahin

Archived Theses and Dissertations

No abstract provided.

Deposition Of Suspensions In A Vertical Converging Tube, Kam-Ho Chan

Theses

The deposition of suspensions in a vertical converging tube with significant gravity effects Was investigated theoretically with control volume - finite difference approach. The fluid was assumed to be incompressible and laminar. The particle density was assumed to be uniform at the inlet of the. tube. The velocity profiles for the fluid considered were (a) Uniform profile, (b) Parabolic profile. The angles of convergence studied were 0°, 5° and 7°. Effects of velocity ratio δ^*(=terminal velocity/mean flow velocity) on the rate of deposition were investigated for δ^*=0,1,10.

It was found that deposition increases with increasing angle …

A Mini-Computer Based General Purpose Interactive Computer Graphics Software System, Victor M. Haddock

Retrospective Theses and Dissertations

This research paper presents the description of a Mini-Computer Based General Purpose Interactive Computer Graphics Software System; which has been installed at the University of Central Florida, College of Engineering PDP 11/34 computer system. This system is a simplified version of MOVIE.BYU. MOVIE.BYU is a General Purpose Interactive Computer Graphics Software System that requires a computer with a word length of at least 32-bits. The MOVIE.BYU system was developed at the Brigham Young University, Utah. Extensive modification was required in order to satisfy the PDP 11/34 FORTRAN IV compiler. In addition, the program routines have been overlayed in order to …

Probable Causes Of Cracking In A Series Of Reinforced Concrete Box Girder Bridges, Steven Milton Bjordahl

Electronic Theses and Dissertations

This thesis is the result of a study undertaken at the request of the South Dakota Department of Transportation (SDDOT) to determine the probable cause of a specific type of cracking that was observed in a series of reinforced concrete box girder bridges. The cracking consists of horizontal cracks through the end diaphragms of the girder and horizontal cracking over the interior bents. Typical crack patterns obtained from information supplied by the SDDOT are shown in Figure 1.

A Model For Optimization Of The Archer's Compound Bow., Mark Aaron Kincy

Masters Theses

"The object of this work is to establish an analysis procedure to permit optimization of the design of ti1e compound bow. The distinguishing features of the compound bow are a system of cables and eccentric pulleys which change the leverage between the bow string and the bow limbs as the string is drawn. This approach concentrates on an accurate representation of the limb mechanics which will allow the design of eccentric wheels to improve the energy storage potential of the bow and thereby increases the velocity of an arrow cast by the bow.

The compound bow is a rather unique …

A Determination Of The Energy Storage Capacity Of The Diels-Alder Reaction Between Methylfuran And Maleic Anhydride As Applied To Storing Solar Energy, Brent Gregory Sparks

Masters Theses

“The heat storage capacity of the Diels-Alder reaction between 2-methylfuran and maleic anhydride is calculated using reaction parameters obtained from solution calorimetry. An equilibrium constant of .614 1/mol and a heat of reaction of 14.33 Kcal/mole were obtained from experiments at 45°C. A reaction ΔC_p of -21.8 cal/mole was calculated from heat capacity information at 25°C. From these parameters, a solution initially seven molar in methylfuran and maleic anhydride was found to have a maximum apparent volumetric heat capacity of about 1.85 times that of water. This maximum occurs at about 335 K. Typical active solar energy schemes operate …

The Effect Of Air Turbulence On The Rate Of Frost Growth On A Horizontal Flat Plate, Dennis Wayne Schulte

Masters Theses

“One factor currently affecting the efficient performance of finned refrigeration coils is frosting. This investigation determined the effect of air turbulence intensity on the growth rate of frost on a chilled flat plate in an effort to reduce the frosting problem.

Air turbulence intensities ranging from 1 to 22 percent were used with an air velocity of 590 fpm, and an air condition of 45°F and 0.0051 lb/lb humidity ratio, for the six hour tests. Additional tests at 7-8 percent air turbulence intensity were made for other air and velocity conditions.

The results showed that the effect of air turbulence …

Chemical Spray Pyrolysis Of Cadmium Telluride., Alok K. Berry

Masters Theses

"Chemical spray pyrolysis is a technique for film growth which is of interest because of its potential for very large scale, inexpensive production of polycrystalline thin film semiconductor materials. Cadmium telluride shows promise as a base material for solar cell applications. Thin films of CdTe have been spray deposited on glass substrates from an aqueous solution containing CdC1₂, Teo₂ and a reducing agent. The films show a zinc blende structure and appear to be intrinsic. Microprobe analysis indicate an excess of Cd, but this is not detectable by X-ray diffraction. The photo absorption studies indicate a direct …

Optimization Of An Investment Strategy For The Mcdonnell Douglas Salaried Savings Plan., Richard Charles Seifert

Masters Theses

"An automated technique is developed to maximize the return on investments in the McDonnell Douglas Salaried Savings Plan. Continual guidance is provided to the participant as to the currently preferred type of investment within the Plan, and to the strategic t iming of withdrawals from the Plan. The decision criteria within the modelled system address the tradeoff s which result from the participant's past investment decisions, his current tax situation, alternative market conditions, withdrawal penalties and o the r Plan characteristics. Decisions are made on the premise that historic performance patterns will continue, though adaptive procedures are included to react …

The Relationship Between Management Training And Other Predictor Variables And Managerial Performance Among Selected Industrial First-Line Supervisors, Joseph Thomas Martelli

Dissertations and Theses @ UNI

The purpose of this study was to determine whether a relationship exists between industrial first-line supervisors' participation in management training programs and subsequent job related performance as assessed by the subjects' overall management by objectives (MBO) performance appraisal rating .

Also, the relationship between managerial performance and predictor variables (age, years of supervisory experience, formal education level, self development, prior management training, and professional society involvement) was assessed.

Twenty-three first-line supervisors from a medium sized manufacturing organization participated in the study. A questionnaire was designed which extracted measures on the predictor variables from the subjects. Corporate management supplied the measure …

A Feasibility Study Of A System For Computer-Aided Selection Of Materials For Industrial Production, Seth Pardee Bates

Dissertations and Theses @ UNI

This study was a comparative analysis of two methods of selecting materials for industrial production. The specific objectives were to find out if (a) a computer-aided materials selection system would select materials which were not significantly different from materials chosen by practicing professional engineers; and (b) the time required by the computer system to select materials would be significantly less than the time required by the engineers.

The criterion measures were (a) the closeness of fit of properties to design specifications for each material selected; and (b) the amount of time consumed by each subject in the selection of each …

A Study Of Industrial Arts Teachers' Opinions Of Gifted And Talented Students In Black Hawk County, Iowa, James Robert Wrona

Dissertations and Theses @ UNI

While the handicapped and disadvantaged have enjoyed the benefit of some unique industrial arts educational programming, relatively little has been done to provide for the special educational needs of gifted and talented students. This may be partially a result of little research completed associating the gifted and talented student with industrial arts. Additionally, legislative support for gifted and talented students has been lacking. It was not until 1978, with the passage of Public Law 95-561, that programs for gifted and talented students have been granted some funding on the federal level. Although this public law can authorize up to $35 …

Transverse Thermal Response Of A Composite Bridge, Michael J. Filla

Masters Theses

"A two-span, composite-design, test structure was subjected to thermal loading. The resultant longitudinal and transverse response was correlated with that calculated by a prior theoretical procedure. The theoretical procedure was reconfirmed for longitudinal stress, and indicated within reasonable probability for transverse stress. No measurable diaphragm influence was observed"--Abstract, page iii.

Structure And Properties Of Neodymium Chromite, David Charles Hitchcock

Masters Theses

"Pure, accepton and Al doped NdCrO₃ were prepared by an organo-metallic process.

The crystal structure and lattice parameters were determined by x-ray diffraction. All compositions were orthorhombic Pbnm.

Pellets were pressed from powders of each composition and sintered to high density in a reducing atmosphere. When a small amount of Fe was substituted for Cr, the powder could be sintered in air.

Electrical conductivity for acceptor doped NdCrO₃ varied from about 1 (ohm cm)^-1 at room temperature to about 10 (ohm cm)^-1 at 900°C, about two orders of magnitude higher than the electrical conductivity of the …

The Design And Development Of A Human Interface For An Intelligent Terminal For A Process Control Industry, V. Rangarajan

Masters Theses

"A complete description of an intelligent Terminal to be used in a Process Control Industry is presented. The system software is discussed. An account of the hardware and software interfaces for the input devices, along with the description of the input devices, is included. The data base used in the system is described with an example. Future enhancements have been proposed."--Abstract, page iii.

Plastic Deformation And Fracture Of Two-Phase Alloys Under Compressive Loading, Abla Mahmoud Zayed

Archived Theses and Dissertations

No abstract provided.

Microfit : A Gate Level Logic Simulator, Yacoub Abraham Alsaka

Theses and Dissertations

Today, gate logic simulation requires large computer facilities. This thesis demonstrates the ability to implement a gate logic simulator in a limited memory environment, specifically in a microcomputer system which usually has limited memory space; at the same time with a reasonable response time. This will permit the use of gate level simulation as a powerful design tool implemented with limited resources or with a desk-top microcomputer. The thesis discusses the development of the MICROFIT logic simulator. The MICROFIT would be used by the students and implemented on the LSI-11 Microcomputer Systems in the Assembly Language Laboratory at Florida Institute …

Load And Resistance Factor Design Of Cold-Formed Steel Structural Members, Boonsong Supornsilaphachai

Doctoral Dissertations

"In a traditional design, the Allowable Stress method has long been used for the design of cold-formed steel structures. In this design approach, the allowable stress is always used to prevent the possible structural failure by using an appropriate factor of safety selected primarily on the basis of engineering judgment and long-time experience.

Recently, the concepts of risk and reliability analysis have been successfully applied to many fields of engineering. By applying the theories of probability and statistics, the load and resistance design criteria for steel structures have been developed for the design of hot-rolled steel shapes and built-up members. …

An Investigation Of The Dynamic Response Of The Activated Sludge Process, Tin-Bai Pan

Dissertations

A new mathematical model, derived from first principles of mass balance, is proposed for describing the mass transfer response of an activated sludge aeration tank in terms of a fluidized bed. The operational data to verify the proposed model were taken from an existing conventional wastewater treatment plant and a bench scale pilot plant.

The mass transfer rate, (K_dA_s), was presented by an empirical dimensionless group function as follows:

((K_dA_s)D_p/D_v) = fA_c (uD_p/ν)a ((ν/D_ν)(MLSS))^b

Or

Sh = f(A_c/A_s ) …

X-Ray Induced Electron Emission, Charles A. Aeby

Chemical and Biological Engineering ETDs

An experimental technique has been developed and successfully used in the measurement of X-Ray induced electron emission from a variety of materials including a group of significance to satellite applications. A database has been established which extends measure emission characteristics to an order of magnitude lower energies than previously available.

A Study Of The Models Describing Fines And Filler Retention By Utilizing Cationic Starch As The Retention Aid, Nen-Sen Chen

Masters Theses

Fines and filler retention under dynamic conditions was studied in this thesis work. Zeta potential of samples are also measured. Dynamic Retention/Drainage Jar and Lazer-Zee Meter were used to accomplish this work. The results have been analyzed by statistical methods. When cationic starch was utilized as a retention aid the pH affected its efficiency, probably because the charge of cationic starch was dependent on pH. This effect was detected by utilizing two-way analysis of variance to find the sources of its interactions with molecular weight and agitation rate. The mechanism was thus determined. At pH 3 and 4, charge neutralization …

High Resolution Laser Absorption Spectroscopy Of Ozone Near 1129.4 Cm-1, Lawrence N. Majorana

Physics Theses & Dissertations

A Beer's Law experiment was performed with a tunable laser to determine self broadened line shape parameters of one infrared absorption ozone line in the v1 band for ten pressures from 0.26 to 6.29 Torr at 285K. SO₂ line positions were used for wavelength calibration. Line shapes were iteratively fitted to the Voigt function at a Doppler width of 29.54 MHz (HWHM) resulting in values for the integrated line• strength, ( S), of (0.144 +/- 0.007 ) x ·10^-20 cm-1/molecule cm-2, line center frequency, (υ_ο) of 1129.426 cm-1 and the Lorentzian contributions to half width, (α …

Sound Absorption In N2-H2O Gas Mixtures At Elevated Temperatures, Roger W. Meredith

Physics Theses & Dissertations

Sound absorption measurements were conducted in N₂ -H₂O gas mixtures at 297, 343, and 387 Kelvin to determine the location of the vibrational relaxation peak of nitrogen on the frequency/pressure, (f/P), axis as a function of humidity and temperature. At low humidities the best fit of the data is to a linear relationship between (f/P)_max and humidity (h) yields a slope of 1 .84 X 10⁴ Hz/ atm mole fraction at all three temperatures. The slope is the same as that reported by Zuckerwar and Griffin (2.00 X 10⁴ Hz/atm mole fraction) but is …

Smada: Stormwater Management And Design Aid, Timothy M. Curran

Retrospective Theses and Dissertations

The Stormwater Management and Design Aid (SMADA) is a computer model formulated to assess stormwater runoff quantity and quality. Applicable theory is reviewed to introduce a discussion of the modeling methodology. A pre- vs. post-development design objective can be incorporated to evaluate runoff quantity and quality for single or multiple land use watershed. Detention and retention facilities are considered and conveyance systems for runoff transmission can be sized. Initial design assessments and consistent design review and evaluation are possible. SMADA is written in the BASIC language and is executed in the interactive mode. No computer cards are required and data …

Optical Phase Modulation Utilizing Magnetoelastic Properties Of Metallic Glasses, Frank R. Trowbridge

Retrospective Theses and Dissertations

Three different optical fiber phase modulators utilizing the magnetostrictive properties of the metallic glass alloy Fe74Co10B16 were constructed. By binding the optical fiber to the magnetostrictive metallic glass, the strain imparted to the metallic glass from the magnetic field is transferred to the optical fiber. The strain on the optical fiber shifts the phase of the light, which can be controlled indirectly by varying the current producing the magnetic field permeating the metallic glass. The performance of the modulators on the basis of optical phase shift as a function of bias magnetic field and optical phase shift as a function …