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Soil Remediation Via Environmentally Processed Asphalt (Epa), S. M. Testa, D. L. Patton Jun 1993

Soil Remediation Via Environmentally Processed Asphalt (Epa), S. M. Testa, D. L. Patton

International Conference on Case Histories in Geotechnical Engineering

Several methodologies are available for the remediation of contaminated soils including bioremediation, vapor extraction, chemical fixation, incineration and direct disposal. A proven innovative and cost effective alternative for the fixation of contaminated soils is via cold-mix Environmentally Processed Asphalt (EPA). EPA methodology utilizes contaminated soil as an ingredient in an industrial process to produce a commercially viable product. Petroleum hydrocarbon and metal affected soil is incorporated with an asphalt emulsion and aggregate to produce a range of cold-mix asphalt product that fulfills the requirements of a variety of end uses. This viable and creative use which is within the intent …


Session 10, 11, 12 − Opening Remarks, Shiming Wu Jun 1993

Session 10, 11, 12 − Opening Remarks, Shiming Wu

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.


Geocomposites For Foundation Uplift Pressure Control In Impermeable Soils, J. C. Chang, J. Y. Wu Jun 1993

Geocomposites For Foundation Uplift Pressure Control In Impermeable Soils, J. C. Chang, J. Y. Wu

International Conference on Case Histories in Geotechnical Engineering

Mat foundations constructed in impermeable soils with a high groundwater table will experience a substantially high buoyancy force due to hydrostatic pressure. Conventional solutions to this problem are to increase the structural weight or install piles or anchors to counterbalance the uplift. These methods are costly, inefficient, and time-consuming. This paper presents a case study to show an innovated approach by using geocomposites to cope with the uplift in impermeable soils. Uplift pressure relief system consisted of geosynthetic materials was installed for a 14- story office and apartment building. The raft foundation was built at 50 feet below ground surface. …


General Report Session No. 8 & 9: Forensic Engineering — "Where Things Went Wrong". Geo-Economy-Adequate Geotechnical Solution, Allen W. Hatheway, John Brodie, Larry P. Jedele Jun 1993

General Report Session No. 8 & 9: Forensic Engineering — "Where Things Went Wrong". Geo-Economy-Adequate Geotechnical Solution, Allen W. Hatheway, John Brodie, Larry P. Jedele

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.


Discussions And Replies Session 11, Karen Brakefield, Aswath V. Rao, Dieter Genske Jun 1993

Discussions And Replies Session 11, Karen Brakefield, Aswath V. Rao, Dieter Genske

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.


General Report Session No. 10, 11 And 12: Case Histories Of Geotechnical And Hydrological Management And Remediation Of Solid, Hazardous And Low-Level Radioactive Wastes, Hari D. Sharma Jun 1993

General Report Session No. 10, 11 And 12: Case Histories Of Geotechnical And Hydrological Management And Remediation Of Solid, Hazardous And Low-Level Radioactive Wastes, Hari D. Sharma

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.


Liquefaction During The October 12, 1992, Egyptian Dahshure Earthquake, Ahmed-W. Elgamal, Mohamed Amer, Korhan Adalier Jun 1993

Liquefaction During The October 12, 1992, Egyptian Dahshure Earthquake, Ahmed-W. Elgamal, Mohamed Amer, Korhan Adalier

International Conference on Case Histories in Geotechnical Engineering

On October 12, 1992 a moderate earthquake MB = 5.9 (MS = 5.2) occurred about 18 km southwest of the center of Cairo and resulted in significant damage to numerous poorly constructed structures. Soil liquefaction associated with the occurrence of large sand-boils was observed close to the epicenter. As a consequence, a main road suffered a maximum settlement of about 1.75 m. In this study, the earthquake characteristics, soil profiles and resulting liquefaction are discussed. The observed liquefaction mechanisms provide valuable information on the seismic response of Nile deposited alluvial soils. Such soils constitute much of the inhabited …


Kinetic Study Of Decomposition Of Azo Dyes And Phenol In Advanced Oxidation Processes Reaction Mechanisms, Pathways And Intermediates, Hung-Yee Shu May 1993

Kinetic Study Of Decomposition Of Azo Dyes And Phenol In Advanced Oxidation Processes Reaction Mechanisms, Pathways And Intermediates, Hung-Yee Shu

Dissertations

Advanced Oxidation Processes (AOP) are an emerging technology for treatment of various hazardous organics in wastewater and groundwater. However, the kinetics and mechanisms for AOP have not been well understood. A mechanism including light intensity was studied for the decomposition of azo dyes and phenol in an AOP reactor with a 5,000 watt low pressure mercury lamp. UV light absorption is an important parameter. The effect of pH, hydrogen peroxide dosage, and dye concentration on the decomposition of azo dyes in an H2O2/UV reactor were also studied. Reaction pathways and intermediates of phenol oxidation by different …


Competition Between Two Microbial Populations In A Sequencing Fed-Batch Reactor And Its Implications For Waste Treatment Applications, Sitaram Dikshitulu May 1993

Competition Between Two Microbial Populations In A Sequencing Fed-Batch Reactor And Its Implications For Waste Treatment Applications, Sitaram Dikshitulu

Dissertations

Pure and simple competition between two microbial populations in a sequencing fed-batch reactor (SFBR) was studied both at the theoretical and experimental level. Competition occurred for a single chemical pollutant which could serve as the sole carbon and energy source for both competitors. A mathematical model describing the process under inhibitory kinetics (as is usually the case with hazardous and toxic substances) was derived and theoretically analyzed. The model predicts that the dynamics of a SFBR, and the kinetics of biodegradation, result in a complex set of operating regimes in which neither species, only one species, or both species survive …


A Review Of Acetabular Prostheses For Total Hip Arthroplasty, Jennifer Anne Citarella May 1993

A Review Of Acetabular Prostheses For Total Hip Arthroplasty, Jennifer Anne Citarella

Theses

This study explores the evolution, design, and clinical progress of contemporary prostheses used in orthopaedic reconstruction of the socket of the hip joint. A literature search was performed to study acetabular implants, as used in total hip arthroplasty. The history of the design of these implants is chronicled. Next, the anatomy of the acetabular region and the surgical technique performed to replace the hip socket are presented. A comprehensive discussion of the design features, rationale, and clinical results for commercially available cemented and cementless prostheses follows.

Hydroxyapatite, a bioceramic which has just recently been approved for applications in total hip …


Integration Of Pneumatic Fracturing To Enhance In Situ Bioremediation, Conan Dante Fitzgerald May 1993

Integration Of Pneumatic Fracturing To Enhance In Situ Bioremediation, Conan Dante Fitzgerald

Theses

The purpose of this thesis was to study the anticipated benefits of integrating pneumatic fracturing with in situ bioremediation. Since pneumatic fracturing increases subsurface air flow in low permeability formations, it has the potential to overcome many of the major limiting factors of microbial growth and activity. A new innovation called pneumatic bio-injection can further enhance in situ bioremediation by efficiently dispersing biological solutions, including microorganisms, into a formation.

Bench scale experiments were conducted to examine the ability of microorganisms to survive the pressures and stresses associated with pneumatic injection. Tests conducted at pressures ranging from 60 to 500 psi …


Comparison Of Heart Rate With Chest Wall Vibrations, Kofi M. Arbuah May 1993

Comparison Of Heart Rate With Chest Wall Vibrations, Kofi M. Arbuah

Theses

A study is done using a Microwave Interferometer as a computer-assisted non-invasive cardiopulmonary monitor. The Microwave Interferometer is used to record the mechanical vibration of the anterior chest wall by recording the velocity of the displacement of the chest wall. The objective is to first, record mechanical vibrations of the anterior chest wall at different heart rates, and second, attempt to identify the relation between heart rate and chest wall vibration.

The system uses two channels, the first signal produced by the Microwave Interferometer is a record of the velocity of the displacement of the chest wall caused by the …


Mechanism Of Pneumatic Fracturing, Trevor Compton King May 1993

Mechanism Of Pneumatic Fracturing, Trevor Compton King

Theses

This thesis investigates the mechanism of pneumatic fracturing in geologic materials such as soil and rock. Pneumatic fracturing is a recently developed technique for increasing the permeability of geologic formations by the controlled injection of high pressure air. Present applications are focusing on the in situ remediation of contaminated soil and ground water, although pneumatic fracturing has other geotechnical uses such as pumping well enhancement.

A comprehensive literature review of a related technology known as hydraulic fracturing is presented, which serves as background for development of a pneumatic fracturing model. Pressure-time histories from actual pneumatic injections are analyzed in detail …


An Experimental Investigation Of Wear Behavior Of Ultra-High Molecular Weight Polyethylene Under Sliding Motion, Elham Zand-Moghaddam May 1993

An Experimental Investigation Of Wear Behavior Of Ultra-High Molecular Weight Polyethylene Under Sliding Motion, Elham Zand-Moghaddam

Theses

This project investigates the effect of sliding motion on the materials that are used as bearing surfaces of human total-joint replacement prostheses.

The tests are performed with a specially designed equipment based on pin-on-disk machine. The testing machine is designed and constructed to reproduce sliding motion, applied to spherical ended metal "Canine-Head" components such as dog hip acting on a flat polyethylene surface. The sliding motion is performed by applying different constant loads for 5,000,000 cycles. The tests are carried out with the wear specimen lubricated by deionized water.

The purpose is to produce delamination, which is the severe wear …


Distributed Economic Systems With Agents That Learn, Stanley Foster Perry May 1993

Distributed Economic Systems With Agents That Learn, Stanley Foster Perry

Dissertations and Theses

Economic systems are distributed in the sense that economic agents make decisions without any central control. Prices, quantities, wealth, and market structure emerge from the interaction of agents acting in their own self interest. The concepts and language of systems science are used to define economic systems in a manner that captures and articulates the distributed nature of economic systems. Further, the systems definition permits multiple views of the economic system, and in addition, allows the agents to "step outside" the system in order to study it.

Economic systems are defined in such a way that it is feasible to …


The Application Of Neural Networks To Optimal Robot Trajectory Planning, Daniel J. Simon May 1993

The Application Of Neural Networks To Optimal Robot Trajectory Planning, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Interpolation of minimum jerk robot joint trajectories through an arbitrary number of knots is realized using a hardwired neural network. Minimum jerk joint trajectories are desirable for their similarity to human joint movements and their amenability to accurate tracking. The resultant trajectories are numerical rather than analytic functions of time. This application formulates the interpolation problem as a constrained quadratic minimization problem over a continuous joint angle domain and a discrete time domain. Time is discretized according to the robot controller rate. The neuron outputs define the joint angles (one neuron for each discrete value of time) and the Lagrange …


Practical Optimization Modeling For Contaminant Plume Management, Richard C. Peralta, Alaa H. Aly May 1993

Practical Optimization Modeling For Contaminant Plume Management, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to greatly speed the process of computing desirable groundwater pumping strategies for plume management. They make the process of computing optimal strategies fairly straightforward and can help minimize the labor and cost of groundwater contaminant clean-up.


Analysis Of Cutthroat Flume Discharge Ratings, Liyan Ren May 1993

Analysis Of Cutthroat Flume Discharge Ratings, Liyan Ren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sixteeen sets of original laboratory data collected by many investigators for various Cutthroat flume sizes are thoroughly reviewed and organized. Best-fit discharge parameters are obtained by performing the free-flow analysis and the submerged-flow analysis. Then, the transition submergence can be calculated. Afterwards, the unified free-flow and submerged-flow discharge parameters are developed for each flume size in order to generalize the calibrations for Cutthroat flumes. This is a very tedious process requiring a trial-and-error approach. Finally, comparisons are made of the measured laboratory discharges with the predicted discharges for both free flow and submerged flow using both the best-fit and the …


One-Dimensional Computer Modeling Of Thermal And Water Quality Characteristics Of Coldwater Lake, Wa, David Kevin Whitaker Apr 1993

One-Dimensional Computer Modeling Of Thermal And Water Quality Characteristics Of Coldwater Lake, Wa, David Kevin Whitaker

Dissertations and Theses

Coldwater Lake is a new lake formed when a massive mudflow down the Toutle River Valley, caused by the eruption of Mount St. Helens on May 18, 1980, blocked the natural outlet of Coldwater Creek. This research utilizes physical, biological and chemical data collected at Coldwater Lake during the sun1mers of 1989 and 1990 to calibrate and verify the one-dimensional computer models CE-THERMRl and CE-QUAL-Rl for Coldwater Lake. CE-THERM-R1 was used to simulate thermal characteristics in Coldwater Lake during the summer stratification periods of 1989 and 1990. The model was calibrated to 1989 data and was verified with 1990 data. …


Minutes Tractor Test And Power Museum April 14th, 1993, Tractor Museum Apr 1993

Minutes Tractor Test And Power Museum April 14th, 1993, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Use of tractor test building for museum.


Cross-Cultural Issues In The Management Of German-Owned Business Subsidiaries In Hampton Roads, Teja Ulrich Apr 1993

Cross-Cultural Issues In The Management Of German-Owned Business Subsidiaries In Hampton Roads, Teja Ulrich

Engineering Management & Systems Engineering Theses & Dissertations

'Culture' can be described as patterns of thinking, feeling and acting that distinguish one cultural group from another. Cultural diversity is therefore likely to introduce variety to organizations in which individuals from different national backgrounds are working together. Although this variety bears the potential for an improvement of the cognitive development in the organizations, managers of multicultural business organizations tend to perceive cultural diversity as a disadvantage. This thesis attempts to identify the impact of cultural differences between Germans and Americans on organizations in which German managers work with American employees. German managers of eight business subsidiaries in the Hampton …


Longitudinal Study Of Plasma And Erythrocyte Selenium Levels In Type I Diabetic Children During Development And Treatment Of Ketoacidosis, Pi-Hsia Fan Apr 1993

Longitudinal Study Of Plasma And Erythrocyte Selenium Levels In Type I Diabetic Children During Development And Treatment Of Ketoacidosis, Pi-Hsia Fan

Chemistry & Biochemistry Theses & Dissertations

Most studies on the biological activity of selenium have focused on its role at the active site in the ubiquitous enzyme, glutathione peroxidase (GSH-Px) which catalyzes the removal of hydrogen peroxide and organic hydroperoxides (1). A connection between selenium deficiency and a wide range of diseases in animals and humans has been reviewed (2). Development of various forms of human cancer (3), failure of the immune system (4), as well as some cardiovascular diseases (5) have been reported or suspected to correlate with selenium deficiency. However, the physiological function of selenium in these different diseases is not fully understood, and …


Competitive Enzyme Immunoassay By Polyclonal Antibodies Against Organophosphorus Pesticides, Kuo-Lan Wen Apr 1993

Competitive Enzyme Immunoassay By Polyclonal Antibodies Against Organophosphorus Pesticides, Kuo-Lan Wen

Theses and Dissertations in Biomedical Sciences

Organophosphorus compounds (OPs) comprise one of the major classes of pesticides in use today because they are highly effective and less toxic. Because of their extensive use, there is a need for monitoring OPs in water and vegetables. Gas chromatography (GC) is the usual method for OPs screening, but it is time-consuming and has the high cost of instrumentation. The goal of this project was to find an easy method which was sensitive and had less instrumentation required to test OPs.

Microwells and microtubes were utilized as the solid-phase immobilization for the development of an enzyme immunoassay for OPs. A …


Simulation Model For Predicting The Impact Of Progressive Diseases In The U.S. Population By Tracking, Biju Suseelan Apr 1993

Simulation Model For Predicting The Impact Of Progressive Diseases In The U.S. Population By Tracking, Biju Suseelan

Masters Theses

Computer Aided Simulation is the process of designing a mathematical-logical model of a real system and experimenting with this model on a computer. Simulation encompasses a model building process as well as the design and implementation of an appropriate experiment involving that model. A simulation experiment involves observing the dynamic behavior of a model by moving from state to state in accordance with well-defined operating rules designed into the model. This research contains the development of a novel approach for the HIV transmission dynamics by using computer simulation to track the HIV positive individuals in a population and to determine …


Analysis Of Weighted Fan-Out/Fan-In Volume Holographic Interconnections, Gregory P. Nordin, P. Asthana, B. Keith Jenkins, A. R. Tanguay Mar 1993

Analysis Of Weighted Fan-Out/Fan-In Volume Holographic Interconnections, Gregory P. Nordin, P. Asthana, B. Keith Jenkins, A. R. Tanguay

Faculty Publications

The feasibility of employing volume holographic techniques for the implementation of highly multiplexed weighted fan-out/fan-in interconnections is analyzed on the basis of interconnection fidelity, optical throughput, and complexity of recording schedule or implementation hardware. These feasibility criteria were quantitatively evaluated using the optical beam propagation method to numerically simulate the diffraction characteristics of volume holographic interconnections recorded in a linear holographic material. We find that conventional interconnection architectures (that are based on a single coherent optical source) exhibit a direct trade-off between interconnection fidelity and optical throughput on the one hand, and recording schedule or hardware complexity on the other. …


Terrain Classification In Sar Images Using Principal Components Analysis And Neural Networks, Mahmood R. Azimi-Sadjadi, Saleem Ghaloum, R. Zoughi Mar 1993

Terrain Classification In Sar Images Using Principal Components Analysis And Neural Networks, Mahmood R. Azimi-Sadjadi, Saleem Ghaloum, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The development of a neural network-based classifier for classifying three distinct scenes (urban, park and water) from several polarized SAR images of San Francisco Bay area is discussed. The principal component (PC) scheme or Karhunen-Loeve (KL) transform is used to extract the salient features of the input data, and to reduce the dimensionality of the feature space prior to the application to the neural networks. Employing PC scheme along with polarized images used in this study, led to substantial improvements in the classification rates when compared with previous studies. When a combined polarization architecture is used the classification rate for …


A New Goodness-Of-Fit Test For The Weibull Distribution Based On Spacings, Mark C. Coppa Mar 1993

A New Goodness-Of-Fit Test For The Weibull Distribution Based On Spacings, Mark C. Coppa

Theses and Dissertations

The critical values for a new goodness-of-fit test based on spacings are generated for the Weibull distribution when the shape parameter is known. The critical values are used for testing whether a set of observations follow a Weibull distribution when the scale and location parameters are unknown. A Monte Carlo simulation with 10,000 iterations is used to generate the critical values for sample sizes 5(5)35 at shape parameters k equal to 0.5(0.5)1.5 and for sample sizes 5(5)20 at shape parameters k = 2.0(1.0)4.0. A Monte Carlo power study of the Z* test statistic using 5000 iterations is accomplished using nine …


Simulated Thermal Performance Of A Solar Heated Floor, Michael F. Kocher, James A. Deshazer, Gerald R. Bodman Mar 1993

Simulated Thermal Performance Of A Solar Heated Floor, Michael F. Kocher, James A. Deshazer, Gerald R. Bodman

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A low cost, simple solar heating system consisting of an active collector with an In-Floor Heat Distribution and Storage (IFHDS) system was developed in response to the energy crisis of the 1970s. A two-dimensional finite difference model was developed and used to simulate the performance of IFHDS system cross-sections. Simulation runs were conducted with a steady-periodic model for the temperature of the solar-heated air in the IFHDS system cross-section. The steady periodic simulation results indicated IFHDS system energy efficiency increases with decreasing air temperature in the room above the IFHDS system, peak temperature of the solar-heated air in the IFHDS …


Spartan Ii: An Instructional High Resolution Land Combat Model, Edwin H. Harris Jr. Mar 1993

Spartan Ii: An Instructional High Resolution Land Combat Model, Edwin H. Harris Jr.

Theses and Dissertations

This project improved SPARTAN, a high resolution land combat model demonstrator. SPARTAN was originally developed as a hands-on trainer for land combat modeling students because there were no models specifically designed to teach the analysts how the models function. SPARTAN is built to demonstrate the techniques used in the current generation of US Army high resolution models. Like the original, the model is primarily a small scale attrition (both direct and indirect fire) model. The model represents 12 soldiers involved in the following processes: target search, target selection, direct fire engagement, indirect fire engagement, movement, reaction to fire, obstacle breaching, …


Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For The Normal Distribution, David A. Gwinn Sr. Mar 1993

Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For The Normal Distribution, David A. Gwinn Sr.

Theses and Dissertations

New techniques for calculating goodness-of-fit statistics for normal distributions with parameters estimated from the sample are investigated. Samples are generated for a Normal(0,1) distribution. Critical values are calculated for five modifications to the Anderson-Darling statistic and five modifications to the Cramer-Von Mises statistic. An extensive power study is done to test the power of the new statistics versus the power of the unmodified statistics. Powers of six of the new statistics show minimal to no improvement, two of the new statistics show a marked decrease in power, and two of the new statistics show an overall increase in power over …