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Theses and Dissertations

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Hierarchical Interactive Theater Model (Hitm): An Investigation Into The Relationship Between Strategic Effects And Ooda Loops, Richard K. Bullock Mar 2000

Hierarchical Interactive Theater Model (Hitm): An Investigation Into The Relationship Between Strategic Effects And Ooda Loops, Richard K. Bullock

Theses and Dissertations

Airpower's strength lies in being able to quickly strike the enemy directly where they are vulnerable while being unhampered by geography and surface forces. Airpower theory suggests the effects of these strikes propagate throughout an opponent1s military system yielding catastrophic output or strategic effects. Despite this theory being a cornerstone of US Air Force doctrine, current Air Force models do not seem to capture airpower's inherent strength. Since these models are used to support budgetary decision making, the United States may not be funding the airpower capability it needs.

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A Decision Support Tool To Aid Campaign Planners In Selecting Combat Aircraft For Theater Crisis, Christopher D. Buzo Mar 2000

A Decision Support Tool To Aid Campaign Planners In Selecting Combat Aircraft For Theater Crisis, Christopher D. Buzo

Theses and Dissertations

One way of comparing alternative deployment plans is to examine how combat aircraft tasked within a deployment plan meet the combat commander's requirements. Both the absolute capabilities and the campaign-specific issues affecting the operational capabilities of those aircraft could assess a set of combat aircraft, unique to a deployment plan. This research-develops a non-absolute, campaign-specific decision Support tool to assess the effect of campaign-specific issues on a set of deployable Air Force combat aircraft. This research is conducted in three phases. Cognitive Task Analysis (CTA) and Multi-Attribute Preference Theory (MAPT) methodologies are applied to in-person and telephone interviews with subject …

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A Tabu Search For Scheduling And Rescheduling Combat Aircraft, Kevin M. Calhoun Mar 2000

A Tabu Search For Scheduling And Rescheduling Combat Aircraft, Kevin M. Calhoun

Theses and Dissertations

Scheduling an air campaign is time and labor intensive. Exacerbating the problem, combat planners use manual methods to accomplish much of this daunting but critical task. While some work has been done to automate the process, the approaches used generate schedules that must undergo major modifications before they are "flyable." Planners, therefore, distrust the results and use the automated features of the software sparingly. Additional problems arise due to the lag time between the publication of the Air Tasking Order (ATO) and the start of the ATO day. During this time, conditions change in the dynamic battlespace (aircraft break, runways …

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Extensible Markup Language As A Weather Tool, Michael J. Calidonna Mar 2000

Extensible Markup Language As A Weather Tool, Michael J. Calidonna

Theses and Dissertations

This thesis is a proof of concept work that will extend the Core Mapping Application Program Interface (CMAPI) components to include weather data. The CMAPI project is headed by Air Force Research Lab (AFRL)/Information Directorate Information Handling Branch (IFEB) at Rome labs in Rome, New York. This work extends the CMAPI project in two distinct areas. The first goal is to figure out how to overlay and display weather data on a dynamically linked Internet platform. This was accomplished by incorporating existing data from the Air Force Weather Agency (AFWA) into the CMAPI program in a static environment. The other …

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A Tabu Search Metaheuristic For The Air Refueling Tanker Assignment Problem, Shay R. Capehart Mar 2000

A Tabu Search Metaheuristic For The Air Refueling Tanker Assignment Problem, Shay R. Capehart

Theses and Dissertations

In a joint effort between Air Mobility Command (AMC) and the Air Force Institute of Technology, we present a Tanker Assignment Problem (TAP) Tool capable of providing tanker mission plans for deployment scenarios. Due to the complex nature of extracting a mission plan from the Combined Mating and Ranging Planning System (CMARPS), AMC requires a tool to provide similar results in a simpler and less time consuming manner. The tool developed allows AMC to input several receiver groups consisting of various aircraft types and numbers. Each receiver group contains a point of origin and destination, with the option of providing …

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Factors Affecting Perceptions Of Ethics Within Organizations: A Case Study Of Organizations Within Aeronautical Systems Center (Asc), David W. Carlson Mar 2000

Factors Affecting Perceptions Of Ethics Within Organizations: A Case Study Of Organizations Within Aeronautical Systems Center (Asc), David W. Carlson

Theses and Dissertations

This thesis studied some of the factors that can be used to help predict perceptions of ethical climate within organizations. specifically, five organizations within Aeronautical Systems Center (ASC) were analyzed by evaluating four years of cultural survey data. The factors that were studied were analyzed through the use of different statistical processes (to include a regression analysis) to order to determine if they could significantly predict the perceptions of the ethical climate of the five ASC organizations studied. The factors were also analyzed to determine how influential the significant factors were in predicting perceptions of the ethical climate of the …

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Development Of A Real Time Guidance System For A Kinematic Test Vehicle, Orhan Cekic Mar 2000

Development Of A Real Time Guidance System For A Kinematic Test Vehicle, Orhan Cekic

Theses and Dissertations

Differential carrier phase GPS measurements are capable of giving centimeter-level accuracies. These accuracies have many potential applications for safety and control of various types of vehicles. For this research, a real-time guidance system is developed. The real-time guidance system can be divided into two components: hardware and software. The hardware component consists of two GPS receivers (one base, one mobile), two wireless 115 Kbaud transceivers, and two laptop computers. One computer is for the reference station and other is for the mobile receiver interface and graphical display. The guided vehicle is a golf car called the Remote Sensing Autonomous Vehicle …

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Investigation Of Laser Beam Combining And Cleanup Via Seeded Stimulated Brillouin Scattering In Multimode Optical Fibers, Bryan J. Choi Mar 2000

Investigation Of Laser Beam Combining And Cleanup Via Seeded Stimulated Brillouin Scattering In Multimode Optical Fibers, Bryan J. Choi

Theses and Dissertations

The purpose of this thesis research was to determine if stimulated Brillouin scattering amplification in multimode optical fibers would exhibit the same laser beam combining and clean-up properties exhibited by SBS oscillation, and to characterize the Brillouin amplification process in a multimode optical fiber. Beam combining in multimode fibers via SBS is being considered as a method of combining low power laser beams into a single beam having higher power and superior spatial coherence for applications such as electro-optic countermeasures. Experimental results demonstrate seeding a 9.5 mm fiber significantly reduced the pump power required to initiate SBS. An amplified Stokes …

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A Neural Network Solution To Predicting Wind Speed At Cape Canaveral’S Atlas Launch Pad, Kenneth P. Cloys Mar 2000

A Neural Network Solution To Predicting Wind Speed At Cape Canaveral’S Atlas Launch Pad, Kenneth P. Cloys

Theses and Dissertations

This thesis demonstrates the potential for using time-delay neural networks to provide Launch Weather Officers (LWOs) at 45th Weather Squadron (45 WS) with advance warning of wintertime (November-March) peak wind speeds at the Atlas launch pad. The 45 WS provides weather support to the United States space program at Cape Canaveral Air Station, NASA's Kennedy Space Center, and Patrick Air Force Base. Due to the complex wintertime environment produced by the effects of friction and instability, 45 WS LWOs consider wintertime launch pad winds their toughest forecast challenge. Neural networks were developed, trained, and tested using observations of wintertime peak …

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Use Of Climatology To Predict Maximum Wind Speeds At The Kennedy Space Center And Cape Canaveral Air Station, Lisa K. Coleman Mar 2000

Use Of Climatology To Predict Maximum Wind Speeds At The Kennedy Space Center And Cape Canaveral Air Station, Lisa K. Coleman

Theses and Dissertations

This thesis uses statistical analysis to forecast the probability of meeting or exceeding the maximum allowable wind speeds for each of the launch pads at the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS). Wind data were collected from the Weather Information Network Display System (WINDS), a collection of 47 meteorological towers located throughout KSC and CCAS, over a period of five winters. A Fortran program was written to calculate conditional probabilities of meeting or exceeding a given threshold speed during eight consecutive one-hour periods, using the current wind direction and peak wind speed as inputs. Forecast probabilities …

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Comparative Analysis Of Mobility Management Schemes In A Low Earth Orbit Satellite Network, Stephen R. Conkling Mar 2000

Comparative Analysis Of Mobility Management Schemes In A Low Earth Orbit Satellite Network, Stephen R. Conkling

Theses and Dissertations

In the 60's the United States and the Union of Soviet Socialist Republics engaged in a "space race" to be the first to put a man on the moon. Today, the space race is between large multinational telecommunication corporations with the winner receiving the financial rewards by providing communication services to the billions without even a simple telephone. Many entrants are using Low Earth Orbit (LEO) satellites to provide the communications infrastructure, but the number of customers a satellite can support is limited by bandwidth available. This resource must be used efficiently, and this involves reducing the management overhead. This …

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Design And Validation Of An Accurate Gps Signal And Receiver Truth Model For Comparing Advanced Receiver Processing Techniques, Phillip Martin Corbell Mar 2000

Design And Validation Of An Accurate Gps Signal And Receiver Truth Model For Comparing Advanced Receiver Processing Techniques, Phillip Martin Corbell

Theses and Dissertations

Recent increases in the computational power of computers and digital signal processors have made possible new, novel signal tracking techniques in GPS receivers. One such technique is known as Direct Correlators Output Processing (DCOP). This technique replaces individual traditional tracking loops with a single Kalman Filter, which jointly processes the received signals while exploiting their correlated noises. DCOP is innovative in its potential to replace the tried and true classical signal tracking loops. It is also an enabling technology for ultra-tightly coupled GPS/INS (Global Positioning System/Inertial Navigation System). Potential benefits of these new tracking techniques include an order-of-magnitude improvement in …

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An Object-Oriented Repository-Based Software Synthesis System, Gary L. Cornn Jr. Mar 2000

An Object-Oriented Repository-Based Software Synthesis System, Gary L. Cornn Jr.

Theses and Dissertations

This research provides a repository on which various Air Force Institute of Technology (AFIT) transformational software synthesis tools can store, share, and manage data using a common repository information model. This information model was created by integrating a variety of separately developed AFIT software synthesis object models into a "wide-spectrum" model. Additionally, a methodology for describing complex relationships between artifacts in the repository is described. These relationships can be used to relate software synthesis artifacts created in a variety of formats, including text, binary, and the AFIT Wide-Spectrum Object Modeling Environment (AWSOME) information model. The relationships can be exploited for …

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Multi-Conjugate Adaptive Optics For The Compensation Of Amplitude And Phase Distortions, Peter N. Crabtree Mar 2000

Multi-Conjugate Adaptive Optics For The Compensation Of Amplitude And Phase Distortions, Peter N. Crabtree

Theses and Dissertations

Two deformable mirrors (DMs) with finite conjugate ranges are investigated for compensating amplitude and phase distortions due to laser propagation through turbulent atmospheres. Simulations are performed based on Adaptive Optics (AO) for an Airborne Laser-type scenario. The Strehl ratio, the number of branch points in DM controls, and the number of iterations to convergence are used as figures of merit to evaluate performance of the Sequential Generalized Projection Algorithm that generates mirror commands. The results are ensemble averages over 32 realizations of the scintillated test fields for each value of the Rytov parameter within the test scenario. The Gaussian beam …

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Modeling Piezoceramic Twist Actuation In Single-Cell Anisotropic Torque Box Of Low-Observable Uav Wing, Peter Cseke Jr. Mar 2000

Modeling Piezoceramic Twist Actuation In Single-Cell Anisotropic Torque Box Of Low-Observable Uav Wing, Peter Cseke Jr.

Theses and Dissertations

The reduction of an aircraft's radar cross section can increase its survivability in hostile airspace by making it more difficult to locate and track by enemy radar. Replacing articulated flight control surfaces with adaptive controls will reduce surface discontinuities, and enhance low observability. Actuation of the aerodynamic surfaces is achieved by an electric field applied to PZT actuators embedded in the top and bottom skins, creating differential strain and shear in the host substrate. This creates torsion about the elastic axis, and a change in the wing lift coefficient. The torsion of the designed baseline UAV's wing torquebox was modeled …

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A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin Mar 2000

A 3d Display System For Lightning Detection And Ranging (Ldar) Data, Michael W. Darwin

Theses and Dissertations

Lightning detection is an essential part of safety and resource protection at Cape Canaveral. In order to meet the unique needs of launching space vehicles in the thunderstorm prone Florida environment, Cape Canaveral has the only operational three- dimensional (3D) lightning detection network in the world, the Lightning Detection and Ranging (LDAR) system. Although lightning activity is detected in three dimensions, the current LDAR display, developed 20 years ago, is two-dimensional. This thesis uses modern three-dimensional graphics, object-oriented software design, and innovative visualization techniques to develop a 3D visualization application for LDAR data.

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Linking Engineer Career Orientation And Human Resource Management Practices: Does Fit Affect Retention?, Cynthia M. Davis Mar 2000

Linking Engineer Career Orientation And Human Resource Management Practices: Does Fit Affect Retention?, Cynthia M. Davis

Theses and Dissertations

Turnover of the Air Force civil engineering (CE) officers is becoming increasingly important, as levels of CE Captains consistently decreases. Allen and Katz (1986) identified three career orientations of engineers based on their job preference-project, professional, and management engineers. Shepard (1958) suggested a dual-ladder promotion system to meet the cancer desires of technical and management workers. Additional research has proposed "desired" Human Resource Management (HRM) practices to facilitate the retention of each type of career-based engineer (Lee and Maurer, 1997). In an effort to determine if these career orientations, along with Air Force HRM practices, were linked to declining retention, …

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Navigation Of Satellite Clusters, Jeffrey S. Davis Mar 2000

Navigation Of Satellite Clusters, Jeffrey S. Davis

Theses and Dissertations

The relative position determination of a cluster of satellites in near circular orbit was investigated in previous thesis work. The purpose of this thesis is to extend the concept to cover absolute position determination. A Bayes filter is used for the estimator with dynamics based on the two-body problem extended to account for J2 perturbations. Measurements consist of combining Global Positioning System (GPS) data for each satellite and range data between the satellites. Simulations were conducted investigating the accuracy obtainable when combining the measurements for input into the filter. Performance results consist of comparing the magnitude of the time error …

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An Incentive Model For International Telecommunications, Jeffrey R. Del Vecchio Mar 2000

An Incentive Model For International Telecommunications, Jeffrey R. Del Vecchio

Theses and Dissertations

This study developed a new defensive model for global voice communications. It uses a n-person, zero-sum, cooperative and non-cooperative game to optimize the coalitions revenue after the possibility of a network service provider being tampered by an adversary. This research optimized two measures of effectiveness (coalition revenue and network provider revenue) of international telecommunications coalitions by hardening network service providers and improving their respective revenue with incentives. A multi-criteria optimization problem was developed to establish the strategic competition between the coalition defender and attacker. Irrespective of the amount of incentives, a applicable hardening and tampering strategy can be obtained. All …

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An Evaluation Of Microburst Prediction Indices For The Kennedy Space Center And Cape Canaveral Air Station (Ksc/Ccas), Steven N. Dickerson Mar 2000

An Evaluation Of Microburst Prediction Indices For The Kennedy Space Center And Cape Canaveral Air Station (Ksc/Ccas), Steven N. Dickerson

Theses and Dissertations

A wet-microburst event on 16 August 1994 at the Kennedy Space Center's Shuttle Landing Facility alerted forecasters from the 45th Weather Squadron (45WS), the provider of weather support to the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS), to the challenges of wet-microburst prediction. Although there was no operational impact, this event caused the 45WS to revise their severe thunderstorm forecasting procedures to specifically address microbursts, resulting in the locally developed Microburst-Day Potential Index (MDPI). MDPI provides a several-hour outlook of microburst potential based on the results of the Microburst and Severe Thunderstorm (MIST) project. The 45WS also …

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Quantifying The Protonospheric Effect On Prism, Kelly B. Doser Mar 2000

Quantifying The Protonospheric Effect On Prism, Kelly B. Doser

Theses and Dissertations

The total electron content (TEC) contribution to a Parameterized Real-time Ionospheric Specification Model (PRISM) calculation has been studied using protonospheric TEC measurements made by Global Positioning Satellites (GPS). Including the protonosphere proved challenging to both the calibration of GPS measurements and execution of PRISM. Though 46 days of GPS measurements were acquired, only 40 were successfully calibrated, and only 35 of those were used in the study. Data issues such as availability and completeness as well as measurement quality affected 6 of the days used. Calibration was done at Pittsburgh by excluding all measurements below 40.750 N. latitude cutoff. This …

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Distributed Object System Engineering For Terminal Aerodrome Forecast Validation And Metrics Processing, James S. Douglas Mar 2000

Distributed Object System Engineering For Terminal Aerodrome Forecast Validation And Metrics Processing, James S. Douglas

Theses and Dissertations

Distributed object systems are a very complex intertwining of heterogeneous hardware, software, and operating systems coupled with communication networks of varying protocols and capacities. Distributed components offer improved performance through parallel processing, improved expansion and scalability opportunities through modularity, improved availability through replication, and improved resource sharing and interoperability through interconnection. This research provides a distributed system design methodology to validate terminal forecasts and gather metrics for the Air Force Weather Agency. Proven principles such as component reuse and architectural development are applied through the use of parameterized types and design patterns. A client/server measurement model is developed to show …

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An Experimental Investigation On Periodic Forced Vibrations Of A Bladed Disk, Colin J. Duffield Mar 2000

An Experimental Investigation On Periodic Forced Vibrations Of A Bladed Disk, Colin J. Duffield

Theses and Dissertations

Aircraft engine blades are subject to harmonic forcing produced from periodic wakes created by fixed stators. Prolong or repeated exposure at blade resonant frequencies can cause vibration-induced fatigue, otherwise known as High Cycle Fatigue (HCF). Structural mistuning coupled with HCF causes premature blade failures, excessive operational costs and increased engine servicing. This study offered a novel approach to characterize mistuning effects on bladed disk forced vibration behavior. A model fan reduced in dynamic scale from an operational jet engine fan and with weak inter-blade coupling was fabricated. Aerodynamic disturbances produced by the stators were replicated by magnets attached to a …

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Feature Selection For Predicting Pilot Mental Workload, Julia A. East Mar 2000

Feature Selection For Predicting Pilot Mental Workload, Julia A. East

Theses and Dissertations

Advances in technology have the cockpits of the aircraft in the Air Force inventory increasingly complex. Consequently, mental demands on the pilot have risen. In some cases, mental demands were so overwhelming that pilots have forgotten basic flying techniques, such as G-straining maneuvers. The results have been fatal. Recent research in this area has involved collecting psychophysiological features, such as electroencephalography (EEG), heart, eye and respiration measures, in an attempt to identify pilot mental workload. This thesis focuses on feature selection and reduction of the psycophysiological features and subsequent classification of pilot mental workload on multiple subjects over multiple days. …

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Effects Of Moisture Content In Solid Waste Landfills, Craig P. Eck Mar 2000

Effects Of Moisture Content In Solid Waste Landfills, Craig P. Eck

Theses and Dissertations

Solid waste landfills are an extremely complex and heterogeneous environment. Modeling the biodegradation processes within a landfill must involve an understanding of how environmental factors affect these processes. Arguably, the most important environmental factor influencing biodegradation processes is solid waste moisture content. This research effort, which is an extension of a system dynamics model previously presented by Colborn (1997) and amended by Benter (1999), attempts to understand and model the effects of moisture content on waste degradation and landfill gas generation. The new moisture structure that was added to the previous models provides a better representation of the impact of …

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Multi-Objective Evaluation Of Target Sets In A Logistics Network, Paul D. Emslie Mar 2000

Multi-Objective Evaluation Of Target Sets In A Logistics Network, Paul D. Emslie

Theses and Dissertations

This thesis addresses the selection of target sets to disrupt an adversary's logistics network in a wartime environment. In the presence of many objectives--such as reducing maximum flow, lengthening routes, avoiding collateral damage, all at minimal risk to our pilots--the problem of determining the best target set is complex. Previous efforts have not adequately considered the value of the remaining network functionality after target destruction. In addition, current network targeting procedures optimize target sets with respect to only a single metric. This thesis uses a multi-objective decision analysis framework capturing actual targeting decision-maker values and preferences to evaluate and analyze …

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A Combined Inventory And Delivery Model For Repairable Items, Bahtiyar Eren Mar 2000

A Combined Inventory And Delivery Model For Repairable Items, Bahtiyar Eren

Theses and Dissertations

Traditionally, logistics analysts have treated the delivery problem separate from the inventory and repair problems. In other words, each of these three problems-delivery, inventory, and repair-are treated individually. We combine the vehicle routing problems and inventory allocation problems in a single formulation. Furthermore, lateral re-supply is considered, in that supplies are not only available from the main depot, but also from other bases. After we get the lateral re-supply information, we set a delivery allocation plan out of the main depot. Such allocations are then delivered via vehicles stationed at the main depot. There is a repair capability for each …

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Modeling The Effect Of Nonlinear And Rate-Limited Sorption On The Natural Attenuation Of Chlorinated Ethenes, Peter P. Feng Mar 2000

Modeling The Effect Of Nonlinear And Rate-Limited Sorption On The Natural Attenuation Of Chlorinated Ethenes, Peter P. Feng

Theses and Dissertations

Chlorinated solvents like tetrachloroethene (PCE) and trichloroethene (TCE) are the most common detected groundwater contaminants at Department of Defense installations in the United States. Unfortunately, technologies conventionally used to remediate chlorinated solvent-contaminated groundwater often fall short of achieving regulatory goals. Natural attenuation of chlorinated solvents offers an alternative remediation strategy that may achieve goals. However, the processes involved with natural attenuation are not fully understood, and this lack of understanding has hindered acceptance of natural attenuation by regulatory agencies. This study involved use of a numerical model that incorporated the physical, chemical, and biological processes thought to be relevant to …

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Global Positioning System (Gps) Error Source Prediction, Marcus G. Ferguson Mar 2000

Global Positioning System (Gps) Error Source Prediction, Marcus G. Ferguson

Theses and Dissertations

With the initiation of the navigation accuracy prediction algorithm used to estimate the amount of GPS solution (location and time) error for receivers, the capability to accurately predict solution errors due to the major GPS error sources is growing. Although some sources of error within the GPS solution have been previously analyzed, modeled, and/or accounted for within various modeling efforts, a formal evaluation of the seven major error sources that distort GPS activity has not been officially conducted up until this point. This research offers a logical assessment of all the major GPS error sources and their definitive impact on …

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In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland Mar 2000

In Situ Treatment Of Chlorinated Ethene-Contaminated Groundwater Using Horizontal Flow Treatment Wells, Derek R. Ferland

Theses and Dissertations

The limitations of conventional containment technologies for groundwater contaminated with chlorinated solvents have motivated development of innovative technologies to achieve national groundwater remediation objectives. One inn9vative technology that is currently under development involves metal reductants or catalysts to chemically destroy the dissolved chlorinated solvent. Models are important tools that can be used to help transition this technology to the field. Model studies can be used to gain understanding about the technology, help determine when the prospective technology might work for a given site, and design full-scale field applications.

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