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Full-Text Articles in Engineering

Optimal Utilization Of Field Generated Analytical Data For Site Characterization And Remedial Decision Making, Ronald J. Lester Sep 1994

Optimal Utilization Of Field Generated Analytical Data For Site Characterization And Remedial Decision Making, Ronald J. Lester

Theses and Dissertations

This study developed data quality standards for assessing environmental analytical data quality and its use in remedial decision making, specifically in risk assessment calculations. The primary purpose was to increase the use of field generated data in environmental site investigations versus the continued reliance on costly and time consuming EPA Contract Lab Program data. Increased reliance on field lab data could significantly reduce remedial investigation costs. The standards developed are based on regulatory criteria for data useability, achievable quality in a CLP lab setting, and basic statistical methods. The standards were applied to sets of Volatile Organic Compound data in …


Volatile Organic Compound Emissions From Usaf Wastewater Treatment Plants In Ozone Nonattainment Areas, Brian A. Ouellette Sep 1994

Volatile Organic Compound Emissions From Usaf Wastewater Treatment Plants In Ozone Nonattainment Areas, Brian A. Ouellette

Theses and Dissertations

In accordance with the 1990 Clean Air Act Amendments CAAA, this research conducts an evaluation of the potential emission of volatile organic compounds VOCs from selected Air Force wastewater treatment plants. Using a conservative mass balance analysis and process specific simulation models, volatile organic emission estimates are calculated for four individual facilities--Edwards AFB, Luke AFB, McGuire AFB, and McClellan AFB--which represent a cross section of the current inventory of USAF wastewater plants in ozone nonattainment areas. From these calculations, maximum facility emissions are determined which represent the upper limit for the potential VOC emissions from these wastewater plants. Based on …


Evaluation Of Alternative Methods For Wastewater Disinfection, David C. Piech Sep 1994

Evaluation Of Alternative Methods For Wastewater Disinfection, David C. Piech

Theses and Dissertations

This study investigated the alternative methods of wastewater disinfection. Areas of interest included methods of operation, ease of maintenance, and effectiveness for various types of wastewater. A literature search revealed three major disinfection options, which include chlorination dechlorination, ultraviolet light, and ozone. A questionnaire was sent to the active duty Air Force installations that operate wastewater treatment plants, requesting permit limitations and monthly averages for a variety of wastewater parameters. The majority of Air Force wastewater treatment plants use chlorine for disinfection. Using the data obtained from the questionnaire responses and established wastewater parameters from other research, the basic design …


Standardization Of Protocol For The Sampling, Testing And Abatement Of Asbestos Containing Joint Compound, Gary J. Schneider Sep 1994

Standardization Of Protocol For The Sampling, Testing And Abatement Of Asbestos Containing Joint Compound, Gary J. Schneider

Theses and Dissertations

This study investigated the differing regulatory guidelines from the Occupational Safety and Health Administration and the Environmental Protection Agency concerning the abatement of Asbestos Containing Joint Compound (ACJC). The specific interest was whether or not adequate protection was being afforded demolition workers when exposed to working with ACJC materials that contain less than 1.0 percent asbestos. A spreadsheet was written to estimate the exposure scenario which might be experienced within a given room size on a demolition or renovation jobsite. Spreadsheets were calculated for ACJC with an asbestos content of 0.1 to 0.9 percent in 0.1 increments for rooms ranging …


Solvent Substitution Methodology Using Multiattribute Utility Theory And The Analytical Hierarchical Process, Jaimie S. Tiley Sep 1994

Solvent Substitution Methodology Using Multiattribute Utility Theory And The Analytical Hierarchical Process, Jaimie S. Tiley

Theses and Dissertations

This study developed a multicriteria decision making methodology for the ranking of solvent cleaning process alternatives. This includes development of univariate value functions and criteria and the incorporation or required alternative attributes. It also compares the Analytical Hierarchical Process and Multiattribute Utility Theory in reference to a cleaning substitution process. An actual Air Force cleaning process evaluation problem is considered to verify the research. The test problem ranks several cleaning alternatives for the replacement of a hazardous solvent used in the general cleaning of aircraft engine components.


Status Of Storm Water Pollution In The United States, Lynne A. Urquhart Sep 1994

Status Of Storm Water Pollution In The United States, Lynne A. Urquhart

Theses and Dissertations

The purpose of this study was to determine the status of storm water pollution in the United States Air Force. This is important since most AF bases are now required to have applied for a NPDES storm water permit. The objectives of the study were to: evaluate the sampling rates used at AF bases; determine the pollutants tested for by the AF bases; compare the pollutant concentrations of the AF bases to an EPA water quality standard; and determine if there were any trends in sampling or pollutant concentrations due to seasonal changes or across AF Commands or EPA Regions. …


Developing An Emission Factor For Hazardous Air Pollutants For An F-16 Using Jp-8 Fuel, Donald J. Van Schaack Sep 1994

Developing An Emission Factor For Hazardous Air Pollutants For An F-16 Using Jp-8 Fuel, Donald J. Van Schaack

Theses and Dissertations

The 1990 Clean Air Act amendments drastically changed the legislation of hazardous air pollutants HAPs or air toxics. Title 3 of the act which specifically addresses HAPs now lists 189 substances which may require regulation as air toxics. Consequently, the reporting of HAP emissions from all Air Force operations will be required in the future. However, the Department of Defense DoD does not have methods available to report this information. This thesis develops emission factors for selected HAPs from an F-16 CD aircraft F110 engine operating on JP-8 fuel. The methodology included determining which HAPs should be selected, using past …


A Quantitative Method For Screening Pollution Prevention Program Options At United States Air Force Installations, Wayne M. Williams Sep 1994

A Quantitative Method For Screening Pollution Prevention Program Options At United States Air Force Installations, Wayne M. Williams

Theses and Dissertations

US Air Force installations worldwide are required to implement pollution prevention (PP) programs designed to reduce the release of pollutants to the environment, and the Air Force uses opportunity assessments (OAs) to identify and evaluate waste producing processes that could benefit from a PP project. The OA process guidance provides extensive details on how to identify potential projects and on how to economically evaluate a project selected for implementation. However, it provides only cursory information about how to decide which projects should be selected for this evaluation. This thesis bridges that gap by providing a quantitative model to be used …


Quality Improvement Analysis Of The Air Force Aircraft Maintenance And Munitions Officers Course, Jeffrey T. Acred, James R. Witter Sep 1994

Quality Improvement Analysis Of The Air Force Aircraft Maintenance And Munitions Officers Course, Jeffrey T. Acred, James R. Witter

Theses and Dissertations

Previous research concerning aircraft maintenance officer training focused on the content of the training curriculum of the Aircraft Maintenance and Munitions Officers Course AMMOC. Conversely, this study sought improvement in aircraft maintenance officer training by evaluating the guidance and support provided to AMMOC. Two methods were employed for identifying such opportunities. First, a descriptive model of the training system supporting AMMOC was developed and analyzed. Second, feedback was solicited from AMMOC instructors through the use of a two-round Delphi. The Delphi was employed to develop a consensus among the instructors regarding what improvement opportunities existed and potential means for taking …


Review Of Factors Impacting Cost Benefit Analysis (Cba) For Implementing Improvements To The Air Force Technical Order System, Susan J. Bergin, Terry A. Parsons Sep 1994

Review Of Factors Impacting Cost Benefit Analysis (Cba) For Implementing Improvements To The Air Force Technical Order System, Susan J. Bergin, Terry A. Parsons

Theses and Dissertations

This research focused on developing a Cost Benefit Analysis process for Program Managers to implement when deciding what technical order format-- paper, computerized or automated--to purchase. Factors which determined the outcome are costs life cycle cost considering technical order format qualitative issues characteristics which are benefits of a technical order format and system responsiveness time required to develop or modify a technical order in each format. A literature review revealed problems with the paper technical order format, management infrastructure, quantitative cost estimates for different formats, and different techniques which could be used for a cost benefit analysis. Structured interviews were …


Developing A Template For Logistics Test And Evaluation, Timothy J. Fennell, Jason S. Mogle Sep 1994

Developing A Template For Logistics Test And Evaluation, Timothy J. Fennell, Jason S. Mogle

Theses and Dissertations

Logistics test and evaluation, performed during the developmental test and evaluation effort, is an integral part of the aircraft acquisition process. However, there has been no standard approach to conducting logistics test and evaluation. This study researched past and present approaches to aircraft logistics test and evaluation to determine the most effective method for future programs. We conducted this study using the Delphi method. We solicited the expert opinions of 32 individuals from the logistics test and evaluation field using two rounds of questions. We then statistically analyzed the data to ultimately develop a logistics test and evaluation template. We …


An Analysis Of The Effect Of Personnel Drawdown Initiatives On Aircrew Experience, Keith L. Hedgepeth, Lennie J. Simpson Sep 1994

An Analysis Of The Effect Of Personnel Drawdown Initiatives On Aircrew Experience, Keith L. Hedgepeth, Lennie J. Simpson

Theses and Dissertations

This study analyzes the effects of personnel reduction initiatives on aircrew experience levels of Air Force pilots and navigators. Four key measures of experience were defined, including total flight hours, flying hours in Primary Assigned Aircraft PAA, total hours at time of upgrade to instructor, and total PAA hours at time of upgrade to instructor. Three objectives were established for this study. These objectives measured the degree of change in overall aircrew experience for pilots and navigators in six major weapon systems, to determine if changes in aircrew experience varied by weapon system, and if changes in aircrew experience varied …


Logistics Control Facility: A Normative Model For Total Asset Visibility In The Air Force Logistics System, Eric C. Lorraine, Michael E. Michno Sep 1994

Logistics Control Facility: A Normative Model For Total Asset Visibility In The Air Force Logistics System, Eric C. Lorraine, Michael E. Michno

Theses and Dissertations

Computer simulation was used to evaluate the impact of a Logistics Control Facility LCF with a Total Asset Visibility TAV system on the AF logistics systems ability to support a weapon system. For this study, the B-1B was chosen as the weapon system of interest. Two performance measures, expected fully mission capable rates and expected pipeline quantities, were used to evaluate the simulation results. Two-sample tests were used to compare the current logistics configuration of the B-1B with the same configuration, but with an LCF controlling the movement of assets. The expected FMC rate performance measure showed significant results while …


Benchmarking Customer Service Practices Of Air Cargo Carriers: A Case Study Approach, Patrick D. Lozon, Michael B. Mcdaniel Sep 1994

Benchmarking Customer Service Practices Of Air Cargo Carriers: A Case Study Approach, Patrick D. Lozon, Michael B. Mcdaniel

Theses and Dissertations

This study used the benchmarking process incorporated in a case study approach to determine what the Air Force could learn from the commercial air cargo carriers in regard to customer service practices. The air cargo industry leaders were determined through a previous study to be United Parcel Service, Federal Express, Emery Air Freight, Airborne Freight, DHL Airways, and Burlington Air Express. In addition, the 437th Aerial Port Squadron APS at Charleston AFB South Carolina was the Air Force representative in the benchmarking study. Interviews with air cargo managers were conducted at each carrier’s main hub and at Charleston AFB. The …


Organic Maintenance Performance Measurement: A New Approach, John S. Nehr, William G. Queener Sep 1994

Organic Maintenance Performance Measurement: A New Approach, John S. Nehr, William G. Queener

Theses and Dissertations

The growing role of Air Force Air Logistics Centers ALC in complex, multiyear developmental programs increases the need for effective cost and schedule performance measurement. In order to effectively manage these activities, timely and accurate cost and schedule information must be collected and compared with an established baseline. The ALCs need a new management technique which facilitates this type of performance measurement. A proven approach to cost and schedule performance measurement in weapon system acquisitions is Earned Value EV. This approach, required of contractors who are subjected to the CostSchedule Control Systems Criteria CSCSC, allows the program manager to obtain …


A Maintenance Manpower Study Of The Composite Wing At Mountain Home Afb, Stella T. Smith, Cristina C. Vilella Sep 1994

A Maintenance Manpower Study Of The Composite Wing At Mountain Home Afb, Stella T. Smith, Cristina C. Vilella

Theses and Dissertations

In response to changes in threats, the Air Force has reorganized several flying units into composite wings. They are intended to provide a flexible, rapid deployment force. This study focused on the impact of the composite wing organizational structure on the determination of maintenance manpower authorizations at Mountain Home AFB, the Air Forces first air intervention wing. An opinion survey of maintenance and manpower experts was used to identify factors that are important in the determination of maintenance manpower authorization levels. Statistical analysis identified important-factors and indicated differences in opinion between maintenance and manpower specialists. Factors specific to the composite …


How Effective Has The Air Force Been In Eliminating Its Dependence On Ozone Depleting Chemicals?, L. Susan Willard Sep 1994

How Effective Has The Air Force Been In Eliminating Its Dependence On Ozone Depleting Chemicals?, L. Susan Willard

Theses and Dissertations

This research was undertaken to determine how effectively the Air Force had eliminated its dependence on Ozone Depleting Chemicals. The research was limited to analyzing the impact of ODCs on major acquisition programs. Results indicated existing variables which may be impeding full implementation. Also identified were lessons learned which could be applied to future environmental legislation with potential impact on acquisition programs. In- depth telephonic interviews were conducted with Program Directors responsible for the development and fielding of major Air Force acquisition programs. Analysis revealed that ODCs substantially impacted the acquisition programs to the extent that many programs had classified …


Finite Element Analysis Of Workability In Bulk Forming Processes, Nagi Hosni Abbasi Aug 1994

Finite Element Analysis Of Workability In Bulk Forming Processes, Nagi Hosni Abbasi

Archived Theses and Dissertations

No abstract provided.


Effect Of Poly Acrylate Addition On Coating Color Rheology, Water Retention And Coating Performance, Shambhu Nath Aug 1994

Effect Of Poly Acrylate Addition On Coating Color Rheology, Water Retention And Coating Performance, Shambhu Nath

Masters Theses

Five polyacrylate samples were used to study their effects on coating color rheology, water holding and runnability. The Cylindrical Laboratory Coater was used to apply the coatings and study the runnability of the coating colors. The healing tendencies of the coatings were studied by inducing a scratch under the blade. The higher acid level and degree of crosslinking of the polyacrylate gave higher viscosity and the higher acid level also gave higher water retention. Coating colors containing polyacrylates were less prone to dilatancy at high shear. The addition of polyacrylate reduced the healing of coating colors, but for the same …


Polynomial Real Root Finding In Bernstein Form, Melvin R. Spencer Aug 1994

Polynomial Real Root Finding In Bernstein Form, Melvin R. Spencer

Theses and Dissertations

This dissertation addresses the problem of approximating, in floating-point arithmetic, all real roots (simple, clustered, and multiple) over the unit interval of polynomials in Bernstein form with real coefficients.


A Simulation Study Of Pilots' Ability To Perceive Angular Motion Under The Influence Of Alcohol, Wali N. Mughni Aug 1994

A Simulation Study Of Pilots' Ability To Perceive Angular Motion Under The Influence Of Alcohol, Wali N. Mughni

Master's Theses - Daytona Beach

The study consisted of experimental research to determine the effect of alcohol on the pilots’ ability to perceive angular motion. It was hypothesized that in the absence of visual cues, pilots’ thresholds of perceiving a change in angular motion is adversely affected by alcohol in the blood, thereby increasing the potential to enter a state of spatial disorientation. The experiments were designed to simulate a real time in-flight scenario, in a rotating flight simulator, where angular accelerations could be controlled and pilots’ thresholds of perceiving a change in angular motion could be measured. The study revealed that the subjects registered …


Rear Seat Belt Usage And Comfort, Kuntal Thakurta Aug 1994

Rear Seat Belt Usage And Comfort, Kuntal Thakurta

Masters Theses

Seat belts have been shown to be effective in reducing car crash fatalities and injuries. Despite consistent evidence that seat belts when worn can provide the greatest vehicle occupant protection of all currently available occupant restraint systems, seat belt use rates remain low. The rates of occupants wearing seat belts in rear seats is much lower than front seat occupants. One of the primary causes for occupants not using seat belts in rear seats has been lack of comfort. The purpose of this thesis was to study the relationship of comfort and seat belt use in rear seats. The current …


Modeling Of Ground Water Aquifer Remediation By Pulsed Pumping When Contaminant Transport Is Affected By Physical, Non-Equilibrium Sorption And Desorption, Jeffrey L. Caspers Aug 1994

Modeling Of Ground Water Aquifer Remediation By Pulsed Pumping When Contaminant Transport Is Affected By Physical, Non-Equilibrium Sorption And Desorption, Jeffrey L. Caspers

Theses and Dissertations

This research postulates and demonstrates a modification incorporating rate-limited sorption effects in the USGS SUTRA code for cleanup of a hypothetical sandy aquifer by pump-and-treat remediation methods. Contaminant transport is assumed to be affected by advection, dispersion, and rate-limited sorption/desorption. Sorption is assumed to be either equilibrium or rate-limited, with the rate-limitation described by either a first-order law, or by Fickian diffusion of contaminant through a spherical immobile pore region. Solutions are arrived at by split operator methods for the transport and one-dimensional Galerkin solutions for the solute concentration equations. The resulting model is tested against an analytical Laplace transform …


Use Of Infrared Spectrometry To Determine The Effect Of Trichloroethylene Resident Time On Desorption Rates From Flint Clay, Peter T. Lapuma Aug 1994

Use Of Infrared Spectrometry To Determine The Effect Of Trichloroethylene Resident Time On Desorption Rates From Flint Clay, Peter T. Lapuma

Theses and Dissertations

This laboratory based thesis investigated the desorption rate of trichloroethylene (TCE) from flint clay while varying the resident time of TCE exposed to the clay. It is thought that in long contaminated soil, a majority of contaminant mass will become entrained within the interior of the soil particles to slowly desorb out of the soil over long periods of time. Recent studies suggest that the longer a contaminant is resident in soil, the longer the contaminant will take to desorb from the soil. To understand more about soil desorption, this experiment was developed using infrared spectroscopy to detect TCE vapor …


Numerical Analysis Of The Viscous Flow In A Supersonic Diffuser, Sa'ed A'Rafat Jul 1994

Numerical Analysis Of The Viscous Flow In A Supersonic Diffuser, Sa'ed A'Rafat

Master's Theses - Daytona Beach

The goal of a diffuser is to transform kinetic energy into potential energy with minimum losses in total pressure. Existing supersonic diffusers are based on compression through shock waves. This process is inherently inefficient because of the large losses caused by the shocks. We investigate by means of Computational Fluid Dynamics (CFD) the viscous flow in a supersonic diffuser designed by means of inviscid theory to produce a shock-free isentropic compression. The design is based on the combination of elementary flows. Two simple wave regions connected by a sink flow are used to take a uniform supersonic flow at one …


Radiative Interactions In Multi-Dimensional Chemically Reacting Flows Using Monte Carlo Simulations, Jiwen Liu Jul 1994

Radiative Interactions In Multi-Dimensional Chemically Reacting Flows Using Monte Carlo Simulations, Jiwen Liu

Mechanical & Aerospace Engineering Theses & Dissertations

The Monte Carlo method (MCM) is applied to analyze radiative heat transfer in nongray gases. The nongray model employed is based on the statistical narrow band model with an exponential-tailed inverse intensity distribution. The amount and transfer of the emitted radiative energy in a finite volume element within a medium are considered in an exact manner. The spectral correlation between transmittances of two different segments of the same path in a medium makes the statistical relationship different from the conventional relationship, which only provides the noncorrelated results for nongray analysis. Two features of the MCM that are different from other …


Investigation Of Wall Injectors For Supersonic Mixing Enhancement, Yaacov Haimovitch Jul 1994

Investigation Of Wall Injectors For Supersonic Mixing Enhancement, Yaacov Haimovitch

Mechanical & Aerospace Engineering Theses & Dissertations

A comparative study of the interaction between wall mounted swept-ramp injectors and injector nozzle shape has been conducted in a constant area duct to explore techniques to enhance mixing in scramjet combustors. The scramjet combustors are currently being developed for propulsion systems applications on the envisioned hypersonic vehicles. Short combustor residence time, a requirement for fuel injection parallel to the main flow in the combustor, and an overall strong sensitivity of the vehicle performance to the propulsion system motivated the investigation. The swept-ramp injector investigated in this study produces vortex shedding and local separation downstream of the injector's nozzle exit, …


Numerical Solution Of Nonequilibrium Compressible Nozzle Turbulent Boundary Layers Using Laws Of The Wall And Wake, Ajit A. Prabhu Jul 1994

Numerical Solution Of Nonequilibrium Compressible Nozzle Turbulent Boundary Layers Using Laws Of The Wall And Wake, Ajit A. Prabhu

Mechanical & Aerospace Engineering Theses & Dissertations

Accurate prediction of the development of the boundary-layer thickness is essential in designing hypersonic wind tunnel nozzles using computational fluid dynamics (CFD). The nozzle boundary-layer thickness becomes extremely thin at the throat region. Immediately downstream of the throat, as the flow begins to expand, the boundary-layer thickness grows rapidly. Estimates of grid requirements for resolving the turbulent boundary layer in the throat region using a Navier-Stokes solver have shown that the number of grid points is typically an order of magnitude greater than what is needed to resolve the nozzle exit region. Approximately 80% of the total time taken to …


The Development Of A Method To Extract High Purity Oxygen From The Martian Atmosphere, Dongchuan Wu Jul 1994

The Development Of A Method To Extract High Purity Oxygen From The Martian Atmosphere, Dongchuan Wu

Mechanical & Aerospace Engineering Theses & Dissertations

A glow-discharge in an ambient Mars atmosphere (total pressure of 5 torr, composed of 95% carbon dioxide) results in the dissociation of carbon dioxide molecules into carbon monoxide and oxygen. If the glow-discharge zone is maintained adjacent and close to a silver membrane, operated at temperatures above 400°C, atomic and molecular oxygen, produced by the glow-discharge, can be separated from the other species by atomic diffusion through the membrane to an ultrahigh vacuum region where the desorbed O2 is then collected. Experiments have been conducted to study the behavior of the glow discharge in both molecular oxygen and carbon …


An Experimental And Analytical Investigation Of The Iosipescu Shear Test For Composite Materials, Barry Stuart Spigel Jul 1994

An Experimental And Analytical Investigation Of The Iosipescu Shear Test For Composite Materials, Barry Stuart Spigel

Mechanical & Aerospace Engineering Theses & Dissertations

Mechanical properties of composite materials under shear loading are difficult to determine. The Iosipescu Shear test, originally proposed for metals, has in recent years been applied to composites. It has the advantages of small specimen size, simple loading and a reasonably uniform shear stress in the test section.

The purpose of this work is to study the validity of the Iosipescu test method for measuring the shear modulus and shear strength of composites. Finite element analyses indicate that optimum specimen geometry and load locations depend upon the degree of orthotropy of the composite. Test results for a quasi-isotropic graphite/epoxy laminate …