Engineering Commons^™

Soil-Shrinkage Induced Structural Failure, David Newton Richardson, Richard Wesley Stephenson, Daniel Molloy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This Paper Describes an Investigation into the Causes of Structural Damage to a Retirement Home and the Subsequent Rehabilitation Project. the Investigation Revealed that the Damage Was Caused by Shrinkage of the Soils Beneath the Structure's Foundation as a Result of Dry Weather, Shrinkage-Prone Characteristics of the soils, Deviation from the Original Design, and Poor Construction Techniques. the Structure Was Subsequently Underpinned to Rock using the Inclined Drilled Pier Method. Interaction between Design and Construction Professionals is Also Presented. © ASCE.

Measurement Of The Condensation Coefficient Of Water In The Umr Simulation Chamber, Daniel R. White, James L. Kassner, John C. Carstens, Donald E. Hagen, John L. Schmitt, Darryl J. Alofs, Alfred R. Hopkins, Max B. Trueblood, Max W. Alcorn, William L. Walker

Physics Faculty Research & Creative Works

The UMR Cloud Simulation Facility is described. The facility is designed to provide a controlled environment simulating the conditions of natural atmospheric processes. It consists of two cooled-wall expansion cloud chambers and peripheral instrumentation for generation and characterization of aerosols used for cloud formation studies. Results of initial studies of the growth of warm cloud droplets and inferred measurements of the condensation coefficient are described.

Microstructural Inhomogeneity In Sintered Pb(Mg1/3nb2/3)O3‐Pbtio3 Based Dielectrics, Jyoti P. Guha, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

The sintering behavior and microstructural development of dielectric ceramics based on Pb(Mg_1/3Nb_2/3)O₃‐PbTiO₃ solid solutions are greatly affected by the formation of a liquid phase at ∼ 1290°C. Prolonged sintering at and above this temperature gives rise to an excessive PbO loss and the resultant variation in composition leads to an inhomogeneous microstructure. The inhomogeneity is characterized by the formation of a dense, localized region containing a PbO‐rich liquid near the surface with a porous interior region in the bulk of the sample. Copyright © 1987, Wiley Blackwell. All rights reserved

Integrated Detonator Delay Circuits And Firing Console, Lawson J. Tyler, Paul Nicholas Worsey

Mining Engineering Faculty Research & Creative Works

A detonation system for use with supply of electrical energy has user operable firing console for selectably transmitting unit identification information, firing delay time information and selections from a command set including Output, Delay, Fire (Time), Abort, Power Up (Arm), Input, and Store. The console displays responses or information digested from responses by electrical delay detonators to the commands. The detonators have explosive, a capacitor for storing energy from the supply to set off the explosive, circuitry for charging the capacitor from the supply and transferring the energy from the capacitor to the explosive in response to first and second …

Computer-Aided Testing Of Electrical Machines: Software Development, Max Darwin Anderson, Steven A. Hauk, Robert Laramore, Hardy J. Pottinger

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Stability Of Polynomials Under Correlated Coefficient Perturbations., M. K. Saridereli, Frank J. Kern

Electrical and Computer Engineering Faculty Research & Creative Works

The robust stability of polynomials with respect to real parameter variations is investigated. The coefficients of the polynomial are assumed to be linear functions of several real parameters. An algorithm to calculate the maximum allowable variations of the parameters so the roots still remain in prescribed regions of the complex plane is presented. Examples are given to illustrate the method.

Computer-Aided Testing Of Electrical Machines: Software Development, Max Darwin Anderson, Steven A. Hauk, Robert Laramore, Hardy J. Pottinger

Electrical and Computer Engineering Faculty Research & Creative Works

Computer-aided test stations have been developed for research, experimentation, and testing of electric motors and generators. Data acquisition and control of the machines and drives are provided through a computer and its interfaces. Machines are connected to the computer through transducers for data acquisition, and power electronic drives for machine control. General software was written to enable the monitoring of all transducers continuously on the CRT screen while giving the user manual control of the machines and drives. Specialized software was written for automatic control of the induction, dc, and synchronous machines for specific experiments on each type of machine. …

Current That Kills., Burns E. Hegler

Electrical and Computer Engineering Faculty Research & Creative Works

The authors point out the hazards associated with electricity. Several methods for preventing or coping with inadvertent shocks are described.

A Limitation To The Use Of A Constructive Approach In The Stability Analysis Of Fixed-Point Digital Controllers, Kelvin T. Erickson

Electrical and Computer Engineering Faculty Research & Creative Works

A limitation to the application of a constructive algorithm to the stability analysis of fixed-point digital controllers is demonstrated by an example. The particular system analyzed consists of a fixed-point PI digital controller regulating a first-order process.

The Effect Of Excess Lead Oxide On The Sintering Characteristics And Dielectric Properties Of Lead Magnesium Niobate Ceramics, Dyllan Jye-Lun Hong

Masters Theses

"The effect of lead oxide additions on sintering characteristics and dielectric properties of ferroelectric Pb₃MgNb₂O₉ based capacitors was studied. The basic dielectric compositions were formed by solid state reaction. Densification was studied as a function of PbO content over the temperature range 900 °C to 1000 °C for sintering times one to six hours depending on the amount of additive, and the sintering temperature.

Weight loss, density and shrinkage measurements of each composition were made in order to relate the effects of the excess PbO additions on the densification. The dielectric and electrical properties were …

Design Of A Meta-Assembler For Microprogramming And A Survey Of Microprogram Optimization Techniques, Rahul Saxena

Masters Theses

"The purpose of this thesis is to develop and implement a meta-assembler for microprogramming. Different methods for optimizing microprogram execution and storage are also investigated.

The meta-assembler is of an adaptive type. It allows complete flexibility in the definition of the target machine op-codes and microinstruction field formats. The assembly process consists of two main phases. In the first phase the assembler builds a description of the target machine in terms of its microinstruction field format definitions. In the second phase the source program is assembled into object microcode. The assembler is written in the language Pascal. The assembler is …

Formability Of 356 Aluminum, Karol Krumrey Schrems

Masters Theses

"Although aluminum casting alloys are not often thought of as being formable, this thesis examines this possibility. Aluminum alloy 356 was cast in permanent molds and subsequently deformed by rolling (providing compressive loading) and bending (providing tensile loading). Cold forming was found to be very limited, while forming at elevated temperatures was comparatively easy and permitted reductions of up to 90%. Tensile properties and microstructures were examined in detail. Forming breaks up the eutectic silicon and intermetallic compounds. The yield strength and tensile strength increased almost linearly with increasing total percent reduction. The elongation at first increases with total percent …

Design Of Multivariable Deadbeat Controllers Using Reduced Order Models, Joaquin Alberto Zuniga

Masters Theses

"This study is concerned with the design of minimum Frobenius norm deadbeat controllers using reduced order models. Deadbeat controllers force the non-zero initial states of a linear multivariable discrete time system to the origin of the state space in minimum time. A controller of minimum Frobenius norm achieves such response with least effort.

The deadbeat controllers are designed on the basis of eigenspectrum assignment. In general, this approach permits a freedom in the selection of the closed-loop Jordan matrix which is used in the design of parametric controllers.

In this presentation, it is demonstrated that the task of deadbeat controller …

The Use Of Computerized Data Acquisition Techniques To Measure The Kinetics Of A Batch Flotation Process, Jose Antonio Barrera-Godinez

Masters Theses

"The flotation response of a lead ore was measured by utilization of a computer driven data acquisition system. A symmetric, fast and automatic froth removal and weighing system was attached to a conventional laboratory flotation cell. The rate controlling mechanisms were identified by manipulation of the froth removal rate, (FRR), froth layer thickness, (FT), and air flow rate, (AFR). The production of froth, water, solids and value in addition to value recovery and concentrate grade were determined as a function of time of flotation.

The flotation response was controlled by events dependent of AFR when using shallow froths of less …

Mechanical And Neutronic Properties Of Neutron Absorbing Materials, Donald James Buth

Masters Theses

“The primary neutron absorbing material examined in this project was Boraflex™, which consists of a silicone polymer with boron carbide acting as the neutron absorber. Two aluminum based neutron absorbers, Boral™ and Al-B-Ten, were also examined. Both X-ray and neutron radiography were used to examine the Boraflex™. The neutron radiography gave better resolution in detecting fluctuations in the boron carbide distribution; however, X-ray radiography did perform better in detecting flaws in the base material. Tensile tests were performed to determine the uniformity of Boraflex™'s tensile properties. The average tensile strength was calculated to be 303 ± 15 psi. A small …

Implementing An Mrp System In A Job Shop Environment, Kathleen A. Behnke

Masters Theses

"In today’s highly competitive marketplace, many small manufacturers are struggling to survive. The competition to produce a quality product at a competitive price comes not only from other small companies, but also from larger companies and foreign manufacturers, who have learned to produce in a more economical fashion. The challenge of the small manufacturer is learning to compete.

Every manufacturer, whether large or small, has one basic objective: to be profitable. The profit objective is usually achieved using a three part strategy of maximizing customer service, minimizing inventory investment, and maintaining efficient plant operation.

Small companies, including the one in …

Fluidized-Bed Gasifier Engine System Using Rice Hulls, Luis Cruz Baja

Masters Theses

"The operation of a fluidized-bed gasifier using rice hulls and a spark-ignition, internal combustion (IC) engine on product gas at the optimum reactor conditions and on gasoline produced generator loads of 6.7 KWe and 10.5 KWe at average speeds of 1740 RPM and 1785 RPM and thermal efficiencies of 12.7% and 13.8%, respectively. The diesel engine operation on dual diesel fuel oil (DFO) product gas and 100% DFO generated 8.0 KWe and 8.3 KWe at 1416 RPM and 1552 RPM and thermal efficiencies of 10.2% and 20.2% respectively. The gasoline engine could be run on 100% product gas while the …

The Interfacial Phenomena Of Liquid Copper Of Sapphire Substrates, Jenq Liu

Masters Theses

"The wetting behavior of liquid copper on the sapphire is effected by the crystallographic orientation of the solid surface, the oxygen partial pressure, and the temperature. Each of these influences has been studied by the sessile drop technique, over the oxygen partial pressure range from 10^-2 to 10^-20 atm at temperatures of 1373°K, and 1523°K. The effect of oxygen partial pressure on the liquid copper surface energy follows the Gibbs Langmuir Law.

The crystallographic orientation of the sapphire surface causes variations in the contact angle. This is more significant for higher oxygen partial pressure, but is eliminated at …

An Assessment Of Large Scale Battery Energy Storage For Industrial Loads, Brent Edward Mckinney

Masters Theses

"Reduction of peak demand on utility systems can be beneficial to both utilities and customers. One means of achieving peak demand reduction is by the use of load-leveling batteries. This thesis describes the technical and economic factors for demand side, customer-owned battery energy storage systems. The thesis has taken into account battery costs, converter and balance of plant costs, current utility rates, and customer load profiles typical of those for which battery storage may be feasible. Battery storage system designs and costs were described and quantified by using the results of EPRI project 1275-12. Utilities in the midwest were selected …

The Force On A Lattice Defect In An Elastic Body, R. C. Batra

Mechanical and Aerospace Engineering Faculty Research & Creative Works

It is shown that the force on a lattice defect in an elastic body is, like the force on a disclination in a nematic liquid crystal, a real force which, for equilibrium, must be balanced by an external force applied to the closed surface enclosing the defect. © 1987 Martinus Nijhoff Publishers.

Robust Control Of A Csi-Fed Induction Motor Drive System, Rajiva Prakash, Vittal S. Rao, Frank J. Kern

Electrical and Computer Engineering Faculty Research & Creative Works

An application of modern control theory to the control of a current-source-inverter (CSI) fed induction motor drive system is presented. A linear quadratic Gaussian (LQG) control scheme is developed in which the Kaiman filter is tuned for high robustness by a method of Doyle and Stein. The design is carried out for a sample system, and the robustness analysis and computer simulation results are included. Copyright © 1987 by The Institute of Electrical and Electronics Engineers, Inc.

An Apparatus For The Measurement Of Dc Electrical Conductivity And Seebeck Coefficient Of Semiconductors As A Function Of High Temperature And Oxygen Partial Pressure, George Francis Carini Ii

Masters Theses

"A computer controlled apparatus for the measurement of dc electrical conductivity and Seebeck coefficient as a function of temperature and oxygen partial pressure has been developed. Thermocouples are in electrical and thermal contact with the ends of the specimen bar. This allows both Seebeck and four-wire electrical conductivity measurements to be made in situ. Environmental enclosure of the specimen allows measurements over a range of oxygen activities from 1 to 10^-18 atm. A discussion of the measuring technique with schematics of the apparatus and data retrieval system is made. Results for measurements in selected oxide ceramics are compared to …

The Development Of Glass-Ceramic Matrix Composites And The Crystallization Of Two Glass-Ceramic Matrices, William M. Carty

Masters Theses

"In order to develop ceramic matrix composites for high temperature applications, two glass-ceramic matrices, one an yttrium aluminosilicate (YAS), the other a magnesium aluminosilicate (cordierite), were chosen as possible matrix compositions. Two separate sets of experiments were performed. Specimens were hot pressed and heat treated then analyzed for the crystallization products and C.T.E. Specimens were also prepared containing commercially available ceramic fibers and coated ceramic fibers to investigate fiber/matrix interactions and the effect of fiber additions on the crystallization of the glass matrices. DTA was employed to approximate the crystallization temperature of the glasses and to determine the effect of …

Glass Fiber Reinforced Polycarbonate Composites, Wen Ching Hu

Masters Theses

"The purpose of this work was to develop a transparent glass fiber reinforced polymer composite material which is superior to the transparent unreinforced thermoplastic in mechanical properties but similar in optical clarity. Polycarbonate matrix composite specimens containing 0 to 40 wt% SK-12 glass fiber were studied, with mechanical and optical properties determined as a function of glass fiber content. The mechanical properties -- flexural strength and elastic modulus increased with increasing glass fiber content. The optical properties -- transmission and transparency decreased with increasing glass fiber content. The factors which influence the mechanical and optical properties were investigated"--Abstract, page ii.

Characterization Of The Fluid-Dynamic Mixing Of A Bottom Gas-Injected Channel Reactor Using Low-Temperature Modelling, Jay Bernett Gassel

Masters Theses

"Variables influencing the mixing in a single-phase (30.5 x 60 x 606 cm) and a two-phase (20 x 40 x 200 cm) channel reactor model were studied. Tracer and/or neutral density particle techniques were used to determine an eddy diffusivity, De, for the system(s). Three bubbler arrangements were investigated in the one-phase work. A separate apparatus was developed to withstand the corrosiveness of the tetrachloroethylene used in the two-phase work.

Both the electrical conductivity tracer technique and the neutral density particle technique were shown to be feasible experimental techniques for determining an eddy diffusivity in the systems studied. Decreasing liquid …

The Mechanical Properties Of The Bonne Terre Formation Dolostone According To Carbonate Facies And Moisture Conditions, Sweetwater Mine, Viburnum Trend, Southeast Missouri, Harvey Edwin Goodman

Masters Theses

"The mechanical properties of the Bonneterre Formation dolostone are critical to the design of underground mine openings at Ozark Lead Company's Sweetwater Mine, southeast Missouri. Host rock strength and elastic moduli, as affected by carbonate facies and varying moisture conditions, can influence rock stability in this multi-horizon mine.

Lead and zinc sulfide ores occur throughout the 350 foot-thick Bonneterre formation found in the mining area. Orebodies are mined in all four carbonate facies of the Bonneterre, including the (1) micrite (mudstone/wackestone) and shale facies, (2) the oolitic (packstone/ grainstone) facies, (3) the digitate stromatolite (boundstone) facies, and (4) the planar …

Causal Factors In The Hydration Susceptibility Of Periclase Aggregates, Chao-Min Cheng

Masters Theses

"The findings presented in this thesis are the result of a study of the hydration mechanism of pre-calcined periclase aggregates. It is hoped that these findings will provide the means to develop an economical, stable and hydration resistant layer on the surface of periclase aggregates by coating with appropriate chemical systems.

In the conduct of this study two sources of commercially obtained materials, Steetley 323, and China metal 90-10, supplied by the Quigley company, were characterized and treated with different concentrations of boron-containing water suspensions in order to impose an altered layer which would resist hydration.

Variables affecting hydration investigated …

Optimization Of Richardson's Shale Durability Rating System, John Dell Long

Masters Theses

"The two-cycle sieved slake durability test, performed on specimens initially oven-dried prior to testing, was determined to be the optimum slake durability testing procedure based on 12 variations of the test performed on 12 different shale types. The effects of changing slake durability testing variables was also studied.

Standard Proctor moisture-density and compaction-degradation tests were performed on 11 shales.

A modified version of the ultrasonic cavitation disaggregation test was developed and performed on 14 shales.

Richardson's shale durability rating equation was modified to include or reflect a data base of 14 shales, the results of the 20-min. ultrasonic cavitation disaggregation …

Performance Predictions For Oil Reservoirs Under Water Influx, Briareus Mitchell Wilkinson

Masters Theses

"The intent of this thesis is to develop a program that will give reasonable recovery predictions for oil reservoirs under water influx. The main advantage is to avoid the massive storage and computational requirements of numerical simulators while achieving roughly comparable results. There are many methods already in existence that have not received their full benefit, mainly because they were developed prior to the recent advances of the computer age. This thesis therefore brings some already proven methods together with new techniques in a program which, with the aid of the computer, stimulates new life in these methods. The main …

Property Survey Of Y₂O₃-Al₂O₃-Sio₂-MₓoY Glasses, Amy Lee Applewhite

Masters Theses

"The purpose of this work was to investigate the properties of Y₂O₃-Al₂O₃-SiO₂-M_xO_y glasses. Many M_xO_y components were tested, but TiO₂ and B₂O₃ proved the most interesting. Glasses containing 5 to 25 wt % TiO₂ were melted and found to have improved chemical durability and a higher refractive index and density than the eutectic Y₂O₃-Al₂O₃-SiO₂ starting glass. These glasses could be crystallized to form an opaque glass ceramic. Glasses containing B₂O₃ were formed by exchanging SiO₂ with B₂O₃ while holding the Y₂O₃ and Al₂O₃ content constant. The density, hardness, refractive index, transformation temperature, softening temperature …