Engineering Commons^™

Deformation And Fracture Of Some Aluminium-Magnesium Alloys Under Impact Compressive Loading, Mohamed Ibrahim Hamed

Archived Theses and Dissertations

No abstract provided.

Ion-Exchange And Surface Properties Of Titania Gels From Ti (111) Chloride Solutions, Suzan I Khairy Seleem

Archived Theses and Dissertations

No abstract provided.

Uplift Capacity Of Rigid Pile In Clay Under Inclined Load, Godwin Ikechukwu Ubanyionwu

Open Access Theses & Dissertations

This thesis investigates the uplift capacity of rigid vertical piles embedded in saturated or near-saturated clayey soils subjected to inclined uplifting loads. Pile foundations are widely used in civil engineering applications requiring resistance to both axial and lateral forces, including transmission tower foundations, foundations on expansive soils, and mat foundations in areas subject to rising groundwater tables. While considerable research had addressed compressive load bearing capacity and lateral resistance of piles, experimental data on pile behavior under inclined uplift loading remained scarce at the time of this study. The present study was undertaken to conduct a systematic series of laboratory …

Determining Process Latitude With Electrically Measurable Test Structures, Jonathan Littlehale

Theses

Collection of linewidth data is an important part of photoresist characterization. Linewidth data are usually collected by optical measurements or scanning electron microscopy. Both of these techniques are tedious and time-consuming. In this work, electrically measurable test structures are used to collect linewidth data. These structures use a measured sheet resistance, a known length of conducting material, and the measured resistance of the structure to determine the linewidth. The benefits of using these structures include completely automated data collection and the ability to collect statistically significant amounts of data. This allows the use of existing statistical analysis software to analyze …

A Study In Pervaporation Of Ethanol/Water Mixtures And Its Applications To Membrane-Aided Distillation, Mikel E. Goldblatt

All Theses

No abstract provided.

Slow Rate Sand Filtration With And Without Clinoptilolite: A Comparison Of Water Quality And Filtration Economics, Gordon P. Foreman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Slow rate sand filtration (SSF) amended with a 20 cm surface layer of clinoptilolite, a natural zeolite, was compared to SSF with no amendment in a field scale SSF facility treating 85 m³/d of water. Parameters examined included turbidity, coliforms, and ammonium removal. The control filter with sand and the experimental filter amended with the zeolite were also compared with respect to duration of filter cycle, cold weather operation, and economics.

Amended and unamended filters were approximately equivalent with respect to ammonium and coliform removal at 10° C. The zeolite amended cell was superior to the unamended cell …

Calibration Of A Temperature-Radiation Evapotranspiration Equation For Utah, Payam Foroughi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two reference crop evapotranspiration (ETr) equations were calibrated to the reference crop of alfalfa using 45 meteorological datafiles from 13 scattered sites in Utah and four sites in the neigboring states of Idaho and Wyoming.

The calibrations were done against the Kimberly version of the Penman ETr formula. The first equation required measured inputs of mean air temperature and solar radiation. It was referred to as the Temperature- Radiation ETr equation (ETr= CT x T x Rs). The second equation required measured inputs of mean minimum and mean maximum air temperatures. It was referred to as the New Hargreaves equation …

Cavitation Limits And The Effect Of Aeration On Cone Valves, Bart "L" Mumford

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cavitation in cone valves can cause eventual valve failure. However, little data are available on cavitation limits for solid plug cone valves. Flow conditions were identified for a 6 inch cone valve where incipient, critical, incipient damage, and choking cavitation limits occurred at valve openings between 20 and 70 degrees. A description of how these limits are used to predict cavitation intensity is given. Air was used to reduce the damage levels. Aeration increased the allowable pressure drop for damage free operation 6 to 72 percent for valve openings less than 70 degrees. A chart is given for predicting when …

Design And Field Layout Of Irrigation Flow Measuring Devices In The River-Lab At Utah State University, Abelardo M. Arriaran

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this report was to develop a design and field layout of irrigation flow measuring devices in a design channel in teh River-Laboratory at Utah State University. This study was conducted considering a maximum discharge of 3.5 cfs and the profile of the channel in the selected area. Four kinds of flow measuring devices to be installed in series one after another were considered: a Parshall flume, a broad-creasted weir, a cutthroat flume, and the rectangular sharp-crested weir. The locations given are based on the hydraulic conditions for each device, the available head, the head loss that each …

An Analysis Of The Heating And Densification Process During Rotational Molding Of A Thermoplastic Powder In A Uniaxially Rotating Cylindrical Cavity, Floyd Steven Ribe

Dissertations

This dissertation presents the results of an experimental and theoretical investigation of the heating and densification portion of the rotational molding process in a uniaxial, cylindrical mold.

A thorough literature survey is included which reviewed past analysis of the rotational molding process and other areas that assisted in understanding of the process.

The results presented in this dissertation included an analysis of the densification process by use of Scanning Electronic Microscope (SEM) photography producing intermediate correlations between the physical properties of the densifying material and neck radius of adjacent coalescing spheres. In addition, a hybrid experimental procedure coupled with a …

Rivest-Shamir-Adelman Cryptosystem, Edward A. Fetzner

Theses & Honors Papers

Cryptography, the art of writing secret messages, has been practiced for almost 3000 years. Two people have a message to communicate to each other , with a chance of an outside person intercepting the message before it reaches the receiver . Therefore, the message must be put through an encryption scheme to keep the intervening person from finding the true nature of the message . An encryption scheme is coding a message using an enciphering key and then decoding the coded message with a deciphering key .

Flexible Engineering Software: An Integrated Workstation Approach To Finite Element Analysis, Brant Arnold Ross

Theses and Dissertations

One obstacle preventing more engineers from using finite element analysis (FEA) is the difficulty of transferring data between steps in the modeling process. A Fortran computer program, Rosetta.BYU, has been developed to open data paths between finite element preprocessors (mesh generators) and finite element analysis programs, using a custom data structure. It accepts neutral data files, Version 2.0 IGES data files, and Movie.BYU files for input/output. An application of Rosetta is described. A general workstation manager program, Davinci.BYU, is reviewed that provides a support layer between the engineer and the operating system, organizes software and data files, and facilitates on-line …

Analysis And Optimal Design Of Wind Tunnel Balances, Sung-Ling Twu

Mechanical & Aerospace Engineering Theses & Dissertations

The problem of finding the optimal cross-sectional shape of the elastic cage in wind tunnel balance is formulated and solved numerically. A mathematical model to implement the boundary condition associated with the elastic rigid connection into the finite element method is discussed. Numerical results show that the rigid connection at the end of the elastic cage has significant effect on the stress distribution.

The finite dimensional approach for a three dimensional design sensitivity analysis is derived. Using both the free and rigid boundary conditions, numerical examples are performed and comparisons of the accuracy of design sensitivity analysis between the proposed …

Analytic Forms Of Bidirectional Reflectance Functions For Application To Earth Radiation Budget Studies, Natividad Manalo Smith

Mechanical & Aerospace Engineering Theses & Dissertations

Reflected solar radiative fluxes emerging from the Earth's top of the atmosphere are inferred from satellite broadband radiance measurements by applying bidirectional reflectance functions (BDRFs) to account for the anisotropy of the radiation field. BDRFs are dependent upon the viewing geometry (i.e. solar zenith angle, view zenith angle, and relative azimuth angle), the amount and type of cloud cover, the condition of the intervening atmosphere, and the reflectance characteristics of the underlying surface. A set of operational Earth Radiation Budget Experiment (ERBE) BDRFs is available which was developed from the Nimbus 7 ERB (Earth Radiation Budget) scanner data for a …

Unsteady Transonic Flow Over Slender Bodies, Cevdet Aydun

Mechanical & Aerospace Engineering Theses & Dissertations

The unsteady transonic small disturbance equation for an oscillating slender body is obtained from the full potential equation in cylindrical coordinates by means of a perturbation analysis. The time-dependent body-boundary condition is reduced into a simpler form by matching the outer and inner flows. Also, a time-dependent pressure coefficient over the slender body is derived by means of a matching principle. The simplified form of the body-boundary condition is incorporated into the difference equations at the body axis. This application allows use of the cylindrical coordinate system for the problem. By prescribing several different body-boundary conditions, various modes of body …

Test Derivation For Cmos Iterative Logic Arrays, Ravi Sharma

Electrical & Computer Engineering Theses & Dissertations

Testability criteria for stuck-open (s-op) faults in one-dimensional unilateral iterative logic arrays (ILA) of CMOS combinational cells are considered in this thesis. A functional fault model to represents-op faults i~ an ILA cell is given. The procedure to detect as-op fault needs a pair of test vectors. The first is used to set up the initial conditions required to test the fault and the second is the test which distinguishes between the good and the bad circuit. Based on this approach necessary and sufficient conditions are given for the testability of as-op fault in a CMOS ILA cell. These conditions …

Selecting Non-Point Source Pollution Treatment Practices Using Linear Optimization, John Gardy Garland Iii

Civil & Environmental Engineering Theses & Dissertations

This paper provides a case study application of a linear optimization program as a water quality management tool. The optimization program seeks to minimize the cost of nonpoint source pollution control by selecting the best combination of pollution control management practices for Hampton, Virginia. The management practice options are grass swale roadways, porous pavers, ponds, detention basins and fertilizer management education. Management practice selection is limited by constraints on land-use and water quality. Pollutants evaluated are total nitrogen, total phosphorus, suspended solids, fecal coliforms and biochemical oxygen demand (five-day). The value in the water quality constraints for pollution loading on …

Structural Self-Shadowing And Its Effects On The Thermal-Structural Behavior Of Orbiting Trusses, Jack Mahaney

Mechanical & Aerospace Engineering Theses & Dissertations

The determination of structural shadowing is described. The computation of environmental heat loads for slender structural members in earth orbit is described, and two methods for finite element thermal analysis are described . The effects of self-shadowing on the thermal structural behavior of single truss members and two different trusses are presented. In each case the shadowing produces a noticeable effect on the temperature distributions on truss members, and on the deformations of the trusses.

A Continuous Distillation Operation At The University Of Tennessee At Chattanooga, David H. Cummins

Honors Theses

This paper describes the work done on the design, construction, monitoring, and control of a distillation column. This work was done as a Departmental Honors Project in the School of Engineering at The University of Tennessee at Chattanooga. The column has been completed and the various tests performed with the column have produced satisfactory results. The column parameters are monitored and controlled by automatic controllers with manually adjusted set points. In addition to this, micro-computer based control for the column has been designed, however implementation of this control has not yet been achieved.

The Applicability Of Microcomputers To Local Water Management, Roderick Lee Allen

Dissertations and Theses

Historically, hydrologic models have been available only on mainframe computers and have therefore not been used by local water managers to support daily decisions. The development of the microcomputer presents an opportunity for that to change.

Mathematical models of soil moisture and river routing are selected, developed and tested for use on a microcomputer as an aid to local water management. The models are then integrated with an appropriate data base in a computer program written for a microcomputer. The result is a Decision Support System for local water managers.

In order to evaluate the feasibility of using the Decision …

A Global Resource Allocation Model For An Electrical Utility, Pantelis G. Tinios

Theses

The management of the electric utility company, as the management of any other company, has to make important decisions which will have a direct impact on the company's future operations.

In this study, a global model was devised which enables the management to make more intelligent decisions related to the company's planning process.

The company's goals and subgoals are formulated, in a systematic way, into the mathematical model along with operational and financial constraints. Productivity growth, steady labor force, fuel availability, cash flow requirements, share rating, and coverage were some of the goals to be achieved. The goal programming technique …

On Circular Hvac Duct Design Through Stress Analysis, Chien-Chung Lee

Theses

In this thesis, comprehensive studies through stress analysis of the circular HVAC ducts are made. The ducts are made of thin gaged steel sheet, and reinforced by stiffeners that are made of hot-rolled steel sections of L or C shapes. The ducts are loaded with pressure, its own weight and the possible seismic accelerations. A comprehensive FORTRAN program is developed as an aid Lo achieving the optimum design of circular ducts, i.e. duct thickness, stiffener spacing, stiffener size and seismic span length, Several stress analysis tables and a design parameter plot arc, provided in this thesis Lo facilitate design optimization.

A Comparison Of Training Available To Entry Level Naval And Merchant Marine Engineroom Personnel, Paul J. Bugelski

Theses

Similarities between occupations or industrial environments are often overshadowed by differences between goals, services, or products. From the time that shipboard steam propulsion became a practicality the Naval and merchant marine services have experienced this phenomena. For various reasons, the two sectors have ignored similarities between their respective occupational sub-groups, e.g. engineroom crews, and the training which facilitates each group's performance.

Manning and training problems, related to the evolution of automated shipboard propulsion plants, have been shared by the U.S. Navy and commercial ship operators. Recent events such as the British Falkland Islands crisis and the implementation of the U.S. …

A Diagnostic Study Of Burning Black Powder Via Stroboscopic Laser Schlieren Photography, Donald Bruce Rowland

Theses

The combustion processes and products of a single grain of burning black powder were experimentally investigated via the stroboscopic laser schlieren photographic technique. A high power modulated argon laser system was used in conjunction with a streak camera to provide a dynamic sequence of time resolved, high resolution schlieren photographs of a burning black powder grain. When black powder burns, a multi-phase product is produced consisting of hot gases, solid particles, and a molten liquid spray. The expansion processes of this multi-phase product cloud were recorded and characterized. Molten drops, reactive and nonreactive particles within as well as outside of …

Keeping Up With Technological Change, Karlis V. Kopans

Theses

Advances in technology over the past fifty (50) years have changed virtually everything that touches our lives today to some degree. However, in the last five years or so, these innovations have been combined into products and systems which have visibly begun to change society as we have known it in the past.

Only in recent years, have the affects of technological change or innovation on society begun to be examined. While a fair amount of literature has been published to date on specific areas of technological change, few publications have been produced which provide a general overview of the …

A Maintenance Program Guide For The Non-Technical Building Manager, Luis M. Tavares

Theses

For the most part, the title of Building Manager is conferred upon an individual who is given the responsibility of services support for a facility. However, this title many times is carried by men/women who are responsible not only for the upkeep of the general building, janitorial, and food services but also for the safekeeping of the building equipment, such as mechanical and electrical machinery. At times, these individuals may be involved with general service responsibilities and tend to lose sight of maintenance needs.

In order for the Building Manager to implement maintenance successfully, he/she must understand the close cooperative …

Conversion And Kinetics In The Reaction Of Chloroform With Water Vapor At High Temperatures, Chii-Guang Hwang

Theses

This is an experimental study on thermolytic reactions of chloroform with excess water vapor where kinetic parameters are determined and complete product analysis made at atmospheric pressure over a temperature range from 550to 1050°C. In this study, water vapor was introduced as a reactant to convert chlorine in chlorocarbons to stable HCl which is an easily neutralized end-product and thereby completely destroy chloroform. Substantial amounts of thermodynamically stable species: HCl, CO, CO₂, C(s) etc. were observed as products.

The reaction was studied in a 46cm tubular flow reactor mounted in a furnace that had three independently temperature-controlled heating …

Reactions Of Hydrogen With Chloroform And Trichloroethylene At High Temperatures, Burhan Mahmood

Theses

The reactions of chloroform and trichloroethylene with hydrogen in the temperature range 550 to 1000°C were studied using tubular flow reactors of varying diameters. The residence time range was from 0.05 to 3.0 seconds.Two different concentrations of the chlorinated species were used, each with hydrogen in large excess. Flat temperature profiles (+/- 5°C) were achieved over 80 to 85 per cent of the 45 cm long reaction zone, with inlet gases preheated to about 400°C.

No chlorinated hydrocarbons, products or reactants were observed at /above 850°C. The major products at these temperatures were C₂H₂, C_{2 …}

A Comparison Of The Biodegradation Of Phenol And O-Chlorophenol Using A Municipal Mixed Liquor And Three Commercial Microbial Preparations, Nigel P. Mcmullen

Theses

The biodegradation of phenol and O-chlorophenol was studied in six-liter batch reactors, using a municipal mixed liquor (from the Livingston, NJ treatment plant) that had not previously been exposed to either of the substrates. In addition, three commercial microbial preparations: BI-CHEM (Sybron), Hydrobac (Polybac), and LLMO (General Environmental Science), were tested alone and in combination with the municipal mixed liquor.

It was found that the municipal mixed liquor performed significantly better than any of the commercial preparations by themselves. When the commercial preparations were mixed with the municipal mixed liquor in a ratio of 1:10 it was found that the …

Failure Rates And Leakage Current Increase In Tantalum Capacitors Of Different Manufacturers, Joseph G. Grant

Theses

This study has determined the effect of high humidity and temperature on solid tantalum capacitors, from five different sources.

The reasons for using capacitors from five different prestigious sources is to first determine how the parameters change with the different manufacturing techniques used by the different sources. Secondly to rank the different sources according to reliability. The parameters that were measured before and after the "1000 hour" high temperature and humidity test were, capacitance, leakage current, and equivalent series resistance. All the capacitors showed significant increase in leakage current after the test, but there were wide variations in catastrophic failure …