Engineering Commons^™

Development Of A Model For Predicting The Vertical Profile Of Ozone Based On Ground-Level Ozone Observations And Cloud Cover, Gi-Dong Kim

Doctoral Dissertations

Ozone formed in a chemical reaction is vertically dispersed and mixed with the ozone mass aloft by turbulent convection due to solar radiation. The mixing height, which depends on the stability of the atmosphere, varies by day/night time and by season of year and is characteristic of season and day and night time from year to year. Ground level ozone is generally the combined result of dynamics of the atmosphere resulted from the turbulent convection in the atmospheric boundary layer (ABL), production and destruction processes such as transport from upper air mass, subsequent transport to the ground, photochemical production and …

Evaluation Of Poroton Masonry And Suggestion For Quick Design Procedure, Michael R. Radcliffe

Masters Theses

Poroton masonry units are highly cored extruded clay units with numerous thin webs. They have ground surfaces and are laid on a thin fluid mortar bed, with no mortar in the head joints. They offer the advantages of quick construction, which can be performed by a general labor force.

This thesis describes the results of component and prism testing of Poroton masonry. Compressive strength tests occurred on individual units and on prisms constructed with two units in accordance with the manufacturer’s directions. The average unit compressive strength was approximately 2900 psi. The average prism compressive strength was about 900 psi. …

The Effects Of Dissolved Oxygen Concentration And Biological Solids Retention Time On Activated Sludge Treatment Performance, Jack Joseph Parker

Masters Theses

A bench scale treatment system with dissolved oxygen (DO) control was used to determine the effects of DO concentration and biological solids retention time (BSRT) on treatment performance using the activated sludge process. The four reactors, operating at BSRTs of 20, 10, 5, and 2 days, were fed settled municipal wastewater collected from the Kuwahee wastewater treatment plant in Knoxville, TN. The DO was maintained at different set points in each reactor ranging from 4.0 to 0.2 mg/L.

Experimental results indicate that carbon treatment performance improved, on average, with increasing BSRT but DO had little effect on carbon oxidation. Sludge …

Arsenic Removal For Small Drinking Water Treatment Systems: A Multimedia Cd-Rom For Drinking Water Professionals, Greg A. Harrison

Masters Theses

This thesis, in conjunction with the accompanying CD-ROM, are intended to be used by small public water system operators, owners, regulators, and engineers as an educational tool for future compliance with a lowered Arsenic Maximum Contaminant Level (MCL). The CD-ROM is the third in a series of water treatment technology CDs that were created by a collaboration of Dr. R. Bruce Robinson, the University of Tennessee, and Dr. M. Robin Collins, the Water Treatment Technology Center, the University of New Hampshire. The CD-ROM includes multimedia tools such as video and photos, which will aid in the understanding of the included …

Determining United States Construction Management Aspects To Be Introduced To Construction Management Education In China, Jun Liu

Master of Technology Management Plan II Graduate Projects

The following study describes the current status of China's Construction Industry, highlights its educational system, and identifies the main constraints that restrain the construction industry from assuming a more effective and efficient role in China's impressive economic development.

This study outlines the problems existing in China's construction educational system. Through analyzing United States construction management education, and comparing it with China's construction education, the advantages of the United States construction management education are determined, and recommendations are made to improve China's construction education.

Simulation Of Oil Spills At Environmentally Sensitive Areas Along Egyptian Coasts, Peter Fayez Nasr

Archived Theses and Dissertations

No abstract provided.

Fractionation & Segregation Of Suspended Particles Using Acoustic And Flow Fields, Nazhat Aboobaker

Dissertations

The fractionation of particles by size or by density has many applications in a variety of technologies. Decontamination and separation of fine sediments is useful in treating sediments. The application of acoustic standing wave fields for the fractionation and segregation of suspended particles was studied.

The above technology was implemented at the bench scale by building a Plexiglas chamber. Two ultrasound transducers were fixed to opposite sides of the chamber to generate the acoustic standing wave field. The technology was evaluated using silica dioxide (Si02) (1-5 ~tm) and silicon carbide (SiQ (5-20 ~tm) particle suspensions in deionized water. Due to …

Transit Productivity Analysis In Heterogeneous Conditions Using Data Envelopment Analysis With An Application To Rail Transit, Manuel J. Martinez

Dissertations

This dissertation extends transit productivity analysis by developing a new method of Data Envelopment Analysis (DEA), the linear programming approach to productivity analysis. The new model analyzes productivity of transit working under heterogeneous operating conditions. It is named Two-Farrell DEA for it applies DEA in two stages, DEA (1), that calculates the productivity frontiers at given operating conditions and DEA (2), that uses inputs adjusted by multipliers calculated in DEA (l). The model Two Farrell DEA calculated productivity benchmarks for each rail transit agency and estimated its potential for higher revenue or lower expense improvement. Additionally, the results identify two …

Predicting Thermodynamic And Transport Parameters For Metal Contaminant Sorption To Hydrated Metal Oxides In Aquatic Systems, Paras Trivedi

Dissertations

Hydrated oxides such as HAO,'HFO, goethite, and BA40 are prevalent in soils and sediments as discrete particles or as coatings. These microporous oxides have large surface areas and high affmity for metal ions, and hence they act as both a sink and a source for anthropogenically released metal contaminants. To better understand risks posed by metals in the environment and to develop effective waste management programs, mechanistic models are needed to accurately predict their fate in soils and sediments.

To achieve this objective, sorption of metal ions Sr, Cd, Zn, Ni, and Ca to these oxides were studied with macroscopic …

A Software System For Large-Scale Structural Optimization, Keith M. Macbain

Dissertations

This work is driven by recent developments in mathematical programming, the state-of-the-art of structural optimization, the spectacular performance of linear programming algorithms, and computer hardware developments which imply that applications of structural optimization might be used commonly in engineering design. Currently, there are few general purpose optimization routines available to the structural engineer and much of the work has addressed specific classes of problems. Further, there is little widespread use of the available routines, partly due to the large amount of familiarity one must have with the specific details of both the problem and the optimization method. In response, it …

Characterization Of The Dependant Pile Capacity In Glacial Deposits By Dynamic Load Tests, Upendra L. Karna

Theses

A study of the effects of time on axial pile capacity in glacial deposits is presented in this report. The dynamic and static load database test results of the Route 21, Viaduct Replacement project are studied and analyzed. In this project two sizes (18-inch and 24-inch dia.) of closed end pipe piles varying in length 100 to 150 feet driven through highly variable glacial deposits were utilized. Within a small reach the subsurface conditions and the behavior of pile capacity with time varied considerably. About 112 piles were tested dynamically by Pile Driving Analyzer. Restriking was performed on fifty-nine piles …

Shear Wave Velocity Profiles At Sites Liquefied By The 1999 Kocaeli, Turkey Earthquake, Brady R. Cox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents shear wave velocity profiles for 15 sites liquefied by the 1999 Kocaeli, Turkey earthquake. These profiles are used in order to evaluate each liquefaction site by the simplified shear wave velocity procedure. This procedure allowed for the identification of a potentially liquefiable region within the subsurface at each site. Locating this region at each site allowed for the separation of soils that were too stiff to liquefy from soils that were soft enough to liquefy. Once these soft regions had been identified, they were evaluated to separate granular soils expected to liquefy, from fine-grained soils expected not …

Recommending Egyptian Guidelines For Managing Construction And Demolition (C&D) Waste, Marwa Saad Moussa Alansary

Archived Theses and Dissertations

No abstract provided.

Stormwater Management In Tennessee: Guidelines To Preventative Maintenance Practices And Improvements, Jacob S. Chandler

Masters Theses

The management of urban stormwater runoff is an important issue throughout Tennessee as urban development keeps expanding. With the rise of urban development, there is an ever-growing need for urban stormwater management systems and facilities which are built to protect downstream property owners from potential flood damage as well as to manage and control the increased stormwater runoff. However well-designed a drainage system or facility might be, adequate maintenance is vital for it to function as intended by the design engineer.

This thesis was written to serve as a document that provides information needed to support an effective maintenance program …

Data Analysis And Correlations For The Particulate Matter Continuous Emission Monitoring System Test Program At The Tsca Incinerator, James A. Calcagno, Iii

Masters Theses

A field study was conducted to evaluate the performance of three commercially available particulate matter (PM) continuous emission monitoring systems (CEMS) during 1999-2000 at the U.S. Department of Energy (DOE) Toxic Substance Control Act (TSCA) Incinerator located near Oak Ridge, Tennessee. The incinerator is permitted to treat mixed-waste, Resource Conservation Recovery Act (RCRA) hazardous and nonhazardous waste, and wastes containing polychlorinated biphenyls (PCB). The mixedwaste treated at the incinerator contains both low-level radioactive and hazardous chemical constituents. The air pollution control system of the incinerator utilizes Maximum Achievable Control Technology (MACT), which is comprised of a rapid quench, venturi scrubber, …

Evaluation Of Alternatives For Hydraulic Design Of Bridges With Hec-Ras, William Wesley Peck

Masters Theses

On average, flooding causes over five billion dollars of damage and 99 fatalities per year in the United States alone. These ever-increasing numbers indicate a need for rigorous design procedures for any structures which exacerbate flood risk. The U.S. Army Corps of Engineers Hydraulic Engineering Center (HEC) has developed a computer program called River Analysis System, and more commonly referred to as HEC-RAS or RAS.

HEC-RAS is the best and most recent method for hydraulic design of bridges, and available documentation provides guidance for its use. The author is experienced in hydraulic design of bridges and has developed this thesis …

Ground Movement Associated With Microtunneling, Zhenyang Duan

Doctoral Dissertations

Microtunneling is a trenchless technology for construction of pipelines. Its process is a cyclic pipe jacking operation. Microtunneling has been typically used for gravity sewer systems in urban areas. Despite its good success record overall, several large ground settlement cases caused by microtunneling have been reported. Also, in contrast with large diameter urban tunneling, there are few research projects about the ground settlement caused by microtunneling.

In this dissertation, the ground settlement caused by microtunneling is studied using a theoretical approach, empirical approach, numerical simulation approach, and artificial intelligence approach.

In the theoretical approach, the equivalent ground loss and settlement …

Statistical Properties Of Maximum Likelihood Estimates For Accelerated Lifetime Data Under The Weibull Model, Mahmoud A. Yousef

Doctoral Dissertations

Pipe rehabilitation liners are often installed in host pipes that lie below the water table. As such, they are subjected to external hydrostatic pressure. The external pressure leads to early deformation in the liners, which could ultimately lead to its failing or buckling before its expected service lifetime is achieved. Experiments involving long term buckling behavior of liners are typically accelerated lifetime testing procedures. In an accelerated testing procedure a liner is subjected to a constant external hydrostatic pressure and observed until it fails or for a certain time, t whichever occurs first. Liners that do not fail at time …

Structural Distress Condition Modeling For Sanitary Sewers, Vani Samyuktha Kathula

Doctoral Dissertations

Sewers represent a very substantial and crucial part of our underground infrastructure and a high level of investment is needed to maintain them. Sewers are generally out of sight and, as long as they continued to function reasonably well, they are also out of mind—that is, until any problems such as structural, hydraulic and functional arise. The criticality of any sewer condition is a combination of the risk of failure and the consequences of it. Therefore, a systematic approach is necessary to fully understand and evaluate the conditions of this underground infrastructure. The present state of the art does not …

Adsorption Of Inorganic And Organic Ligands Onto Aluminum Hydroxide And Its Effect In Water Treatment, Peter Pommerenk

Civil & Environmental Engineering Theses & Dissertations

The inorganic anions fluoride, sulfate, and orthophosphate are ubiquitous substances in aqueous environments. These chemicals are also applied in drinking water treatment processes where fluoridation, coagulation with sulfate-based metal salts, or the use of passivating corrosion inhibitors or sequestering agents is practiced. If these ions are present at elevated levels in raw waters or added in the treatment train at points other than directly before entering a finished water reservoir, they can exert a negative influence on the removal of particles and natural organic matter.

Although the water chemistry of these inorganic ions seems to be well understood, their potential …

Modeling Biodegradation Of Chlorinated Groundwater Contaminants Under Iron-Reducing Conditions Of A Constructed Wetland: A System Dynamics Approach, Max E. Johnson

Theses and Dissertations

The purpose of this study is to determine and explore the fundamental processes associated with biodegradation of chlorinated ethenes in iron-reducing conditions of a constructed wetland and to evaluate the impacts of changing conditions (both natural and engineer-controlled) on the system. The modeler uses a system dynamics approach to construct a model that represents behavior in the iron-reducing environment. The model incorporates hematite, a form of oxidized iron (Fe³⁺), as the electron acceptor in microbial biodegradation in the system. Vinyl chloride, cis-dichloroethene, and trans-dichloroethene are known to anaerobically degrade to carbon dioxide in the presence of oxidized iron. …

A System Dynamics Approach To Modeling Temperature Effects In Solid Waste, David A. Jokinen

Theses and Dissertations

The amount of municipal solid waste discarded to landfills is continually increasing even with extensive recycling efforts. The need to understand the behavior of waste in landfills is increased due to the decreasing number of active landfills, communities' concern to the potential hazards associated with landfills, and companies or installations with landfills on-site need to understand landfill behavior comply with new legislation concerning design and detecting hazardous material movement of-site. This research is focused on increasing the understanding of landfill behavior by examining the effects of temperature in a landfill system. A system dynamics approach was used in this research …

Quantitative Validation Of A Model Of Chlorinated Ethene Natural Attenuation, Harold C. Young

Theses and Dissertations

Chlorinated ethenes are among the most prevalent groundwater contaminants at hazardous waste sites nationwide. In an attempt to manage the risks posed by these contaminants, while controlling costs, monitored natural attenuation (MNA) is being considered as a remediation strategy at many sites. MNA relies on naturally occurring physical, chemical, and biological processes in the subsurface to reduce the risk posed by the contamination. The implementation of MNA, however, requires a detailed understanding of these processes, and how they impact contamination at a particular site. One way to gain this understanding is through contaminant fate and transport modeling. In this study, …

Modeling Chlorinated Ethene Removal In The Methanogenic Zone Of Constructed Wetlands: A System Dynamics Approach, Randall L. Roberts

Theses and Dissertations

The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethene, within the confines of the methanogenic zone of a constructed wetland. A system dynamics modeling approach is used. This model is focused on determining conditions that will enhance contaminant degradation. The chemical and biological processes within the methanogenic zone of a wetland system are extremely complex and dynamic processes. The model is broken up into three simultaneous processes: dechlorination, methanogenesis, and fermentation. The system behavior of the methanogenic zone can be adequately described by the classical formulations of representative …

Determining The Value Of Groundwater Contamination Source Removal: A Methodology, Benjamin C. Recker

Theses and Dissertations

Subsurface contamination by industrial chemicals is one of the most prevalent and costly environmental problems facing the United States government. This contamination problem must be managed to protect human health and the environment. Two basic strategies are used to deal with subsurface contamination: source removal and contaminant containment. While much cost and performance data are available for individual technologies associated with each of these strategies, there have been very few studies that have examined the benefits of implementing source removal technologies in order to reduce contaminant containment (and hopefully total) costs. This study examines the tradeoff between extent of source …

Differences In Civil Engineer Perceptions Of Change Based On Prior Training And Experience, Steven W. Lo

Theses and Dissertations

The Department of Defense (DoD) and the United States Air Force (USAF) have moved toward an aggressive stance to competitively source and privatize (CS&P) support functions as much as possible. This move is intended to shrink support costs and redirect the savings to force and equipment modernization. In addition, the USAF hopes to realize improved services, gain access to technology, share risks with contractors, and allow its forces to focus on the core competencies. In order to implement OS&P, the USAF communicates information through two major pathways, passive and active. Passive communication is similar to traditional classroom learning where information …

Chromate Content Bias As A Function Of Particle Size In Aircraft Primer Paint Overspray, David B. Novy

Theses and Dissertations

Spray painting operations using chromate-containing primer paints produce particles which may expose workers to strontium chromate. Chromate contains hexavalent chromium (Cr(VI)) which is a confirmed human carcinogen. It is suspected that the smaller particles contain disproportionately less Cr(VI) than larger particles. In order to determine if a bias in chromate content exists, paint particles were collected and separated based on particle size and the Cr(VI) concentration was determined. Aviation primer paint from the DeSoto and Deft companies was sprayed in a booth and seven-stage cascade impactors were used to separate particles.

A Model For Palladium Catalyzed Destruction Of Chlorinated Ethenes In Contaminated Groundwater, Christopher M. Stoppel

Theses and Dissertations

Groundwater contamination by chlorinated ethenes is a widespread environmental problem. Conventional remediation technologies have shortcomings that have prompted further research into the development of novel treatment technologies. A palladium/ alumina catalyst in the presence of dissolved molecular hydrogen (referred to hereafter as a PD/H₂ system) has been demonstrated to rapidly destroy chlorinated ethene contaminated groundwater. First-order kinetics have been used to model chlorinated ethene destruction in a PD/H₂ reactor. However, catalyst deactivation and regeneration are important processes that also need to be modeled in order to better understand their effect on treatment efficiency. This study presents a model …

Decision Analysis Methodology To Evaluate Integrated Solid Waste Management Alternatives For A Remote Alaskan Air Station, Mark J. Shoviak

Theses and Dissertations

Eareckson Air Station (AS), a remote U.S. Air Force installation, faces the complex decision of selecting a new municipal solid waste (MSW) management strategy to replace its current non-compliant system. This research effort applies value-focused thinking and multiattribute preference theory to decision analysis techniques to produce a multiple-objective decision analysis model that captures all of the site's MSW goals, objectives, and concerns in order to facilitate the evaluation of MSW management strategies available. The model ranks 40 specific MSW management alternatives, which were developed in accordance with the decision-maker's assumptions and constraints, based on how well they meet Eareckson's overall …

An Analysis Of Civil Engineer Officer Contingency Training, Rusty J. Vaira

Theses and Dissertations

The primary objective of this research was to investigate the current overall civil engineer officer contingency training program and determine if civil engineer officers think it is adequately preparing them to perform in a contingency environment. In accomplishing this objective, this research explored the perceptions that officers have about the contingency training that is available through three primary training programs (Home Station Training, Silver Flag training, and Civil Engineer and Services School training). The overall intent of the author was to gauge how the officers feel about their contingency training and offer some suggestions on how to improve the training. …