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Full-Text Articles in Engineering

An Analysis Of Site Parameters Affecting Natural Attenuation In Saturated Soil, William H. Potts Sep 1993

An Analysis Of Site Parameters Affecting Natural Attenuation In Saturated Soil, William H. Potts

Theses and Dissertations

This study investigated the natural attenuation mechanisms and some of the parameters affecting those mechanisms in the saturated zone. A literature search revealed numerous studies of various attenuation and the associated parameters. Much of the literature emphasized biodegradation as the most promising attenuation mechanism. BIOPLUME II(TM), a fate and transport model, was used to simulate the fate and transport of contaminant plume. The effects of the model parameters were investigated by observing the distance a contaminant plume was expected to migrate over a fifty year period. The investigation was limited by the model which excludes chemical reactions and some physical …


Application Of The Simplified Dow Chemical Company Relative Ranking Hazard Assessment Method For Air Combat Command Bases, Raymond A. Sable Sep 1993

Application Of The Simplified Dow Chemical Company Relative Ranking Hazard Assessment Method For Air Combat Command Bases, Raymond A. Sable

Theses and Dissertations

This study investigates the possibility of determining the hazard potential of chemicals on Air Force bases using a relative ranking hazard assessment method. Hazard assessment includes identification of hazards and evaluation of the hazards. Title III of the Superfund Amendments and Reauthorization Act of 1986 requires hazard assessments by all facilities with extremely hazardous substances to prepare release prevention plans. The purpose of the hazard assessments is to provide information to improve the spill prevention, control and countermeasures plans and to identify the substances with the highest hazard potential. Using the results from the hazard assessments, bases cam prepare plans …


A Feasibility Study Of Burning Waste Paper In Coal-Fired Boilers On Air Force Installations, Kenneth P. Smith Sep 1993

A Feasibility Study Of Burning Waste Paper In Coal-Fired Boilers On Air Force Installations, Kenneth P. Smith

Theses and Dissertations

This thesis examined the feasibility of using waste paper derived fuel in coal-fired boilers on Air Force installations in an attempt to help solve air pollution and solid waste disposal problems. The implementation of waste paper derived fuel was examined from both a technical acceptability and an economic feasibility viewpoint. The majority of data for this study was obtained through literature reviews and personal interviews. Waste paper was found to be technically acceptable for use as fuel. However, waste paper has certain characteristics that may create problems during combustion and therefore further research is required. These problems included the possibility …


Development Of A Cost-Effectiveness Methodology To Prioritize Environmental Mitigation Projects, Robert E. Thompson Sep 1993

Development Of A Cost-Effectiveness Methodology To Prioritize Environmental Mitigation Projects, Robert E. Thompson

Theses and Dissertations

A cost-effectiveness prioritization methodology was developed using concepts from the cost-effectiveness technique. The new methodology called the Cost-Effectiveness methodology (CEM) allows the prioritization of mitigation projects across broad categories of hazardous sites as would be ranked among the offices of the Environmental Protection Agency. Two performance criteria were incorporated into the process--rank projects that save the most lives per dollar and enhance general applicability across different categories of risk. A metric was developed that represents the ratio of lives saved per dollar spent on mitigation alternatives of contaminated environmental sites. This metric was incorporated into the CEM to distinguish mitigation …


A Guide To Implementing Reclamation Processes At Department Of Defense Municipal Solid Waste And Construction Debris Landfills, Gregory L. Tures Sep 1993

A Guide To Implementing Reclamation Processes At Department Of Defense Municipal Solid Waste And Construction Debris Landfills, Gregory L. Tures

Theses and Dissertations

This thesis serves as a guide for implementing landfill reclamation techniques on municipal solid waste or construction debris landfills owned, operated, or used by the DoD. The research describes historical and current methods for disposing of solid waste including open dumping, sanitary landfilling, and the development of state-of-the-art sanitary landfill cell technology. The thesis also identifies the factors which have led to the need for new methods of managing municipal solid waste. The vast majority of the study is devoted to identifying actions which should be taken before, during, and after implementation of a landfill reclamation project. These actions include …


A Plan For Coordinating Department Of Defense Emissions Trading, Charles H. Weir Sep 1993

A Plan For Coordinating Department Of Defense Emissions Trading, Charles H. Weir

Theses and Dissertations

The original purpose of this research was to develop a plan to coordinate emissions trading between DoD installations. During the course of this research, findings indicated that restrictions on emissions trading would make such a plan of limited applicability. However, findings did indicate the need for a tool to assist managers with selecting the netting, offset, and banking emissions trading alternatives. Developing this tool became the objective of this research. This objective was fulfilled by developing a management guide to assist environmental managers with selecting the emissions trading alternatives netting, banking, and offsets. Background information was collected by examining literature …


A Parametric Regression Of The Cost Of Base Realignment Action (Cobra) Model, Douglas D. Hardman, Michael S. Nelson Sep 1993

A Parametric Regression Of The Cost Of Base Realignment Action (Cobra) Model, Douglas D. Hardman, Michael S. Nelson

Theses and Dissertations

This study develops a parametric model that is capable of generating accurate estimates of the costs to close Air Force installations. The new model is based upon, but much simpler to use than, the Cost of Base Realignment Action (COBRA) model. COBRA is an economic cost analysis model that requires a minimum of 250 inputs and as many as 700 inputs. The new parametric model requires just 10 input variables and was developed using least squares multiple regression. Comparison of the new parametric model to COBRA indicates that it captures 91 percent of the variance in cost estimates generated by …


Research And Development Project Selection Tools: Probing Wright Laboratory's Project Selection Methods And Decision Criteria Using The Lateral Airfoil Concept, James E. Barger Sep 1993

Research And Development Project Selection Tools: Probing Wright Laboratory's Project Selection Methods And Decision Criteria Using The Lateral Airfoil Concept, James E. Barger

Theses and Dissertations

This research accomplished three major tasks. First it examined familiarity and usage rates for fifteen published R&D project selection methods in the context of a larger general issue, the Air Force's ability to develop and exploit technology. Wright Laboratory served as the focus for the research effort and displayed a greater tendency to use formal methods in 1993 than was shown in prior research. The laboratory's overall preference for simpler models like Checklist, Scoring, and Sorting led to a recommendation that authors familiar with the other techniques communicate them in engineering and management vernacular. Secondly, the study introduced a technological …


Analysis And Development Of An F-5 Pollution Prevention Management Program With Recommendations For Creation Of Similar Programs For Other Aircraft, Janice M. Gavern Sep 1993

Analysis And Development Of An F-5 Pollution Prevention Management Program With Recommendations For Creation Of Similar Programs For Other Aircraft, Janice M. Gavern

Theses and Dissertations

This study developed a pollution prevention program for the F-5 aircraft, and described its utility and applicability as a generic framework for similar programs. A representative set of F-5 technical orders was analyzed by hand, and the identified chemicals, materials, and processes were loaded into a spreadsheet data base for additional analysis. The Environmental Protection Agency EPA 17 chemical list, and lists of ozone depleting chemicals (ODCs) were used as criteria to identify, for minimization, reduction, or elimination from use on the F-5, a hazardous material (hazmat) subset of those chemicals and materials which had already been identified. The identified …


Schedule Estimating Relationships For The Engineering And Manufacturing Development Of Bomber, Transport, Tanker And Surveillance Aircraft Systems, D. Scott Boyd, Brian D. Mundt Sep 1993

Schedule Estimating Relationships For The Engineering And Manufacturing Development Of Bomber, Transport, Tanker And Surveillance Aircraft Systems, D. Scott Boyd, Brian D. Mundt

Theses and Dissertations

This study developed parametric schedule estimating relationships (SERs) for the engineering and manufacturing development (EMD) phase for nontactical aircraft systems. The potential value of this nontraditional approach to estimating schedule duration has been established by previous applications to tactical aircraft, air-launched munitions, and office buildings. Prior research suggested acquisition strategy parameters to be significant schedule drivers. For this study, data on EMD milestone dates and potential schedule drivers were collected on 56 bomber, transport, tanker, and surveillance aircraft systems. Several SERs were developed for these systems using linear regression analysis. The EMD phase was divided into subphases based on significant …


Software Cost Estimating Models: A Comparative Study Of What The Models Estimate, George A. Coggins, Roy C. Russell Sep 1993

Software Cost Estimating Models: A Comparative Study Of What The Models Estimate, George A. Coggins, Roy C. Russell

Theses and Dissertations

This effort developed a consolidated document which highlights and examines differences in definitions, assumptions, and methodologies used by the REVIC, SASET, PRICES, and SEER-SEM cost models. The following research questions were investigated: (1) What differences exist between the cost models? (2) How do these differences impact the resulting estimates? (3) To what degree can we explain and adjust for known differences between the cost models? Seven specific areas were addressed: (1) software development phases, (2) development activities and cost elements, (3) source lines of code and language differences, (4) key model attributes and key cost drivers, (5) implications of Project …


Pollution Prevention Incentives For Major Weapon System Programs, Donna C. Heinz, Dudley C. Wireman Sep 1993

Pollution Prevention Incentives For Major Weapon System Programs, Donna C. Heinz, Dudley C. Wireman

Theses and Dissertations

This research was undertaken to identify positive incentives that would motivate both government personnel and contractors to incorporate pollution prevention into the early design phases of weapon system acquisitions. The adoption and implementation of such incentives would allow the Air Force to reach pollution prevention objectives more efficiently. A literature search revealed little information on the pollution prevention program in the military. In contrast much information was found concerning military cleanup activities. As a result, in-depth personal interviewing was used to measure pollution prevention awareness in Aeronautical Systems Center program offices. Interviews, analysis, and comparisons were made between three groups …


Benchmarking Practices Of Air Cargo Carriers: A Case Study Approach, Mila D. Abalateo, Joni R. Lee Sep 1993

Benchmarking Practices Of Air Cargo Carriers: A Case Study Approach, Mila D. Abalateo, Joni R. Lee

Theses and Dissertations

This research effort used the benchmarking process and a case study methodology to determine what the Air Force can learn from commercial air cargo carriers. A literature search showed that the U.S. air cargo industry leaders are United Parcel Service, Federal Express, Emery Air Freight, Airborne Freight, DHL Airways, and Burlington Air Express. In addition, the 436th Aerial Port Squadron at Dover AFB, Delaware was chosen as the Air Force representative in the benchmarking study. Observations of air cargo operations and interviews with operational managers or applicable experts familiar with air cargo operations were conducted at each carrier's hub and …


An Investigation Of Alternative Metamodels For The Theater Simulation Of Airbase Resources Model, Alistair G. Dally Sep 1993

An Investigation Of Alternative Metamodels For The Theater Simulation Of Airbase Resources Model, Alistair G. Dally

Theses and Dissertations

This study is an exploratory investigation into the development of metamodels of a particular Theater Simulation of Airbase Resources (TSAR) simulation model. Techniques applicable to the development of metamodels from a simulation using an orthogonal two-level fractional factorial experimental design are discussed. The experimental design is found to limit the metamodel form to polynomial linear least squares regression models, and also to greatly simplify the process of building regression models. Using the simulation results from previous research, alternate metamodels are proposed for both the prediction of sorties generated by the airbase system, as modeled by the simulation; and to assist …


An Evaluation Of Aircraft Maintenance Performance Factors In The Objective Wing, Mark A. Gray, Margaret M. Ranalli Sep 1993

An Evaluation Of Aircraft Maintenance Performance Factors In The Objective Wing, Mark A. Gray, Margaret M. Ranalli

Theses and Dissertations

Prior to 1992, organizational maintenance was aligned under a - separate maintenance organization. In 1992, the Air Force restructured into Objective Wings with organizational maintenance aligned under the flying squadrons. This study looks at the impact of this reorganization on maintenance performance factors. The researchers developed maintenance performance models using regression and principal component analysis. Mission Capable Rate and Total Not Mission Capable Maintenance Rate are used as dependent variables. A comparison of key maintenance performance indicators and model predictions before and after the reorganization is accomplished. Based on the results of this analysis, the researchers conclude that there is …


A Comparison Of The Disaster™ Scheduling Software With A Simultaneous Scheduling Algorithm For Minimizing Maximum Tardiness In Job Shops, Barak J. Carlson, Christopher A. Lettiere Sep 1993

A Comparison Of The Disaster™ Scheduling Software With A Simultaneous Scheduling Algorithm For Minimizing Maximum Tardiness In Job Shops, Barak J. Carlson, Christopher A. Lettiere

Theses and Dissertations

The Theory of Constraints (TOC) is the foundation for a computerized scheduling system called DISASTER. Although this system has proven successful in many manufacturing settings, it has potential limitations due to the sequential heuristic process by which it schedules constraints. The objective of this thesis was to determine the extent to which these limitations impact the due date performance of schedules created by DISASTER. This objective was addressed by developing an algorithm to simultaneously schedule multiple constraints in a job shop environment and provide the optimal schedule for minimized maximum tardiness. This algorithm was used to obtain solutions for a …


An Analysis Of The Effectiveness Of The Air Force Drug Testing Program And Four Potential Modifications, Thomas R. Doster, Hubert A. Ross Sep 1993

An Analysis Of The Effectiveness Of The Air Force Drug Testing Program And Four Potential Modifications, Thomas R. Doster, Hubert A. Ross

Theses and Dissertations

This study evaluated the 1992 USAF Drug Testing Program and potential improvements, based on the number of drug users detected, cost, and legal issues. Four potential improvements were examined: (1) increasing the annual amount of random urinalysis; (2) increasing the proportion of commander-directed testing; (3) using a weighted selection technique, and (4) replacing urinalysis with hair testing. For each improvement, the researchers used test and survey results to estimate the number of drug users detected, a cost formula to estimate any changes in cost, and interviews with legal experts to identify any legal issues associated with implementing the modification. Researchers …


An Exploratory Survey Of Methods Used To Develop Measures Of Performance, Kenneth L. Hamner, Charles A. Lafleur Sep 1993

An Exploratory Survey Of Methods Used To Develop Measures Of Performance, Kenneth L. Hamner, Charles A. Lafleur

Theses and Dissertations

Nonmanufacturing organizations are being challenged to provide high- quality products and services to their customers, with an emphasis on continuous process improvement. Measures of performance, referred to as metrics, can be used to foster process improvement. The application of performance measurement to nonmanufacturing processes can be very difficult. This research explored methods used to develop metrics in nonmanufacturing Organizations. Several methods were formally defined in the literature, and the researchers used a two- step screening process to determine the OMB Generic Method was most likely to produce high-quality metrics. The OMB Generic Method was then used to develop metrics. A …


Benchmark Production Scheduling Problems For Job Shops With Interactive Constraints, Stewart W. James, Bruno A. Mediate Jr. Sep 1993

Benchmark Production Scheduling Problems For Job Shops With Interactive Constraints, Stewart W. James, Bruno A. Mediate Jr.

Theses and Dissertations

United States Air Force (USAF) depots have expressed interest in utilizing DISASTER production scheduling software to schedule their maintenance operations. DISASTER attempts to increase system throughput by building effective schedules for system, constraint resources. However, when a system contains multiple, interactive constraints, DISASTER builds the constraint schedules one at a time. Since each successive schedule must adhere to timing restrictions imposed by previous constraint schedules, the quality of the schedules produced by DISASTER is dependent upon the sequence in which the constraints are scheduled. This thesis first developed a set of benchmark problems which provide a diversity of scheduling scenarios. …


An Investigation Of Integrated Product Development Implementation Issues: A Case Study Of Bosma Machine And Tool Corp, F. Paul Khuri, Howard M. Plevyak Jr. Sep 1993

An Investigation Of Integrated Product Development Implementation Issues: A Case Study Of Bosma Machine And Tool Corp, F. Paul Khuri, Howard M. Plevyak Jr.

Theses and Dissertations

This thesis investigated Integrated Product Development (IPD) implementation issues. Research emphasis focused on teams used in IPD, particularly self-directed work teams (SDWTs). The areas addressed in the study were: Work Environment, Team Organization, Training and Education, Group Dynamics and Communication, Motivation, Rewards and Incentives, Measurements, and Contracts. Data was collected using interviews and presented as a case study. The most significant findings on work environment were that the organization's leadership should commit to the teaming idea and sell it to the organization's members. Teams should be organized by choosing members carefully and defining all roles. Personnel should be trained in …


An Independent Evaluation Of Information Systems Support Of The Joint Forces Air Component Commander Concept Of Operations, Gregory R. Kincaid, Richard A. Poligala Sep 1993

An Independent Evaluation Of Information Systems Support Of The Joint Forces Air Component Commander Concept Of Operations, Gregory R. Kincaid, Richard A. Poligala

Theses and Dissertations

This study examines automated Air Tasking Order (ATO) generation and dissemination under the Joint Forces Air Component Commander (JFACC) concept, focusing on an evaluation of information systems support given the differing service philosophies concerning control of tactical air assets. Current Department of Defense doctrine identifies the Contingency Tactical Air Control System Automated System (CTAPS) as the standard automated system for Theater Battle Management planning for the JFACC. To achieve service interoperability, the doctrine requires the use of CTAPS for ATO generation and dissemination when joint operations are conducted under the JFACC concept. A problem arises in that CTAPS is developed …


Scheduling A Medium-Sized Manufacturing Shop: A Simulation Study, Daniel J. Mcfeely Sep 1993

Scheduling A Medium-Sized Manufacturing Shop: A Simulation Study, Daniel J. Mcfeely

Theses and Dissertations

This study examined the application of simple-to-use, low cost scheduling methods to the operating environment of a medium-sized manufacturing shop. Computer simulation was used to evaluate eighteen different scheduling algorithms, each the result of the combination of a loading and a sequencing rule; due date setting was not considered since due dates are exogenously set. The loading rules investigated were Minimum Machine Required, Lowest Average WIP, and Lowest Average Aggregate Priority Level. The sequencing rules investigated were Priority, EDD, FIS, SPT, Slack, and Slack Ratio. The scheduling algorithms were evaluated against performance measures of mean tardiness, mean flowtime, mean percentage …


An Analysis Of The Performance-Risk Trade-Off In Source Selection Decision Making, Richard G. Pierce, Jeffrey E. Wainwright Sep 1993

An Analysis Of The Performance-Risk Trade-Off In Source Selection Decision Making, Richard G. Pierce, Jeffrey E. Wainwright

Theses and Dissertations

Each year the Air Force awards weapon system contracts worth billions of dollars using the source selection process. In the source selection, performance and risk assessments are evaluated to determine the best proposal; the proposal that gives the best overall value. The purpose of this research was to investigate the performance/risk trade-off in the source selection decision making process. The study also examined the effect individual risk propensities and the nature of item being evaluated have on the performance/risk trade-off decisions. Air Force acquisition personnel stationed at Aeronautical Systems Center, Wright-Patterson AFB, OH, who had participated in a source selection …


Incorporation Of Traffic Collision Alert System (Tcas) Advisories On Heads-Up Displays: Enhanced Pilot Response, Hamadeh A. Nureddine Aug 1993

Incorporation Of Traffic Collision Alert System (Tcas) Advisories On Heads-Up Displays: Enhanced Pilot Response, Hamadeh A. Nureddine

Master's Theses - Daytona Beach

This study evaluated the effects that heads-up mounted TCAS displays had on pilot response and workload. Pilot response was evaluated by: (a) response time to a traffic advisory, and (b) number of missed traffic alerts. Workload assessment was accomplished in accordance with NASA's Task Load Index (TLX). Subjects were all licensed pilots with a minimum of a private pilot license and an instrument rating. A total of 32 subjects were randomly assigned to experimental and control groups utilizing HUD-mounted, and conventional, TCAS displays respectively. Performance data was collected during computer-simulated flights, while subjective workload levels were reported at the end. …


An Econometric Analysis Of The Nw/Klm Corporate Alliance, S. Koo Boon Aug 1993

An Econometric Analysis Of The Nw/Klm Corporate Alliance, S. Koo Boon

Master's Theses - Daytona Beach

This thesis investigates whether a corporate alliance between international air carriers is beneficial, considering the changes in the global air transport system. Dividing the research method into three phases, the author first lists and identifies the recent changes in world air transport trends. Then, the author defines the different types of alliances and studies the advantages and disadvantages of these corporate alliances. Finally, a multiple regression analysis is performed using the KLM/Northwest Airlines alliance as a case analysis.


Proposed Smoothing Technique To Avoid Numerical Instabilities In A Hydrodynamic Numerical Model, Thomas P. Abraham Aug 1993

Proposed Smoothing Technique To Avoid Numerical Instabilities In A Hydrodynamic Numerical Model, Thomas P. Abraham

Electronic Theses and Dissertations

Despite every effort being made to produce a completely problem-free computational model, no breakthrough has yet been made. When a numerical model is used to solve a real world problem, there is a tendency for the non-physical spurious waves to creep in. If these waves are not checked, they can lead to serious instability problems. Once these waves are removed, the model should be able to simulate physical phenomenon like circulation, separation, flow reversal in the vertical plane, mixing/transport, convection/diffusion, etc.

When a numerical mode] is made to run for a certain period of time, node-to-node oscillations may arise and …


Rolling Friction Research Instrument, John P. Ward Aug 1993

Rolling Friction Research Instrument, John P. Ward

Masters Theses

An instrument has been analyzed, designed and constructed that will accurately measure the rolling resistance of metallic spheres an plane surfaces subjected to normal loading which will produce contact stresses approaching material yield.


A Study Of Effects Of Flotation Conditions On Flotation Efficiency And Fiber Loss, Wiwat Walaipachara Aug 1993

A Study Of Effects Of Flotation Conditions On Flotation Efficiency And Fiber Loss, Wiwat Walaipachara

Masters Theses

Three variables: (1) consistency, (2) agitation, and (3) bubble size were studied for their effects on flotation efficiency and fiber loss. Flotation was done by using a Hallimond apparatus. The floated and non-floated portions were quantified by image analysis based on number of ink particles and total area of ink. The percent fiber loss was calculated from solids' weights of both portions. The floated part was analyzed by a KAJAANI instrument for fiber length average and distribution.

The results showed that flotation efficiency increased with agitation but decreased with increasing consistency. Fiber loss increased with consistency but decreased with increasing …


Analysis Of Sandwich Plates Subjected To Blast Loading, Vijay Prasad Bulla Aug 1993

Analysis Of Sandwich Plates Subjected To Blast Loading, Vijay Prasad Bulla

Masters Theses

A dynamic analysis is presented for the bending response of square sandwich plates with isotropic core and facings under blast type pressure. The maximum central deflections of simply supported plates under static and dynamic loadings are compared for various thicknesses and elastic moduli. The deviation of the thick sandwich plate results from the pure-bending theory results is presented for various core properties. Small deflection dynamic iso-response plots are shown for different core rigidities. To study the limits of small deformation linearity for various sandwich plates, non-linear results for deformations under high pressure loads are compared with the linear results. The …


Excited Atomic Bromine Energy Transfer And Quenching Mechanisms, Ray O. Johnson Aug 1993

Excited Atomic Bromine Energy Transfer And Quenching Mechanisms, Ray O. Johnson

Theses and Dissertations

Pulsed and steady-state photolysis experiments have been conducted to determine the rate coefficients for collisional deactivation of the spin-orbit excited state of atomic bromine, Br(2p1/2). Pulsed lifetime studies for quenching by Br2 and CO2, established absolute rate coefficients at room temperature of kBr2 = 1.2 ± 0.1 x 10-12 and kCO2 = 1.5 ± 0.2 x 10-11 cm3/molecule-s. Steady-state photolysis methods were used to determine the quenching rates for the rare gases, N2, 02, H2, D2, NO, …