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Air Force Institute of Technology

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Multimission Aircraft Design Study: Electromagnetic Compatibility, Jenna M. Davis Mar 2003

Multimission Aircraft Design Study: Electromagnetic Compatibility, Jenna M. Davis

Theses and Dissertations

The multi-mission aircraft (MMA) technical feasibility study looked at the replacement of the aging fleet of C-135 and C-130 theater based command & control (C2) and intelligence, surveillance and reconnaissance (ISR) fleet. It is proposed that the MMA be out-fitted to combine some or all the functions of existing AWACS, JSTARS, RIVET JOINT, COMPASS CALL, and ABC CC platforms. It would also have links to other manned or unmanned ISR aircraft, as well as satellites. The objective of the proposed design study is to examine the technical risks involved in combining multiple functions onto one aircraft that currently reside on …

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Single-Mode Raman Fiber Laser In A Multimode Fiber, Matthew B. Crookston Mar 2003

Single-Mode Raman Fiber Laser In A Multimode Fiber, Matthew B. Crookston

Theses and Dissertations

The feasibility of a transverse single-mode Raman fiber laser using a multimode fiber has been investigated. The Raman fiber laser operates in low-order transverse modes despite the fact the fiber supports multimode beam propagation. The performance characteristics of the Raman fiber laser are compared with those of the single-pass SRS beam.

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Phasing A Dual Optical Path System Using An Optical Fiber As A Phase Conjugate Mirror, Shawn M. Willis Mar 2003

Phasing A Dual Optical Path System Using An Optical Fiber As A Phase Conjugate Mirror, Shawn M. Willis

Theses and Dissertations

Phase conjugation properties of stimulated Brillouin scattering (SBS) in a short multimode fiber have been investigated with an eye towards its application for a multi-channel double pass master oscillator power amplifier (MOPA) system. In particular, properties of the SBS beam to compensate for the axial and transverse phase distortion between individual channels in a multi-channel amplifier system were studied. Two optical paths were created by covering half of the laser beam with a microscope slide, and also by spatially splitting the wavefronts with a 4 prism set-up. The Stokes beams that traversed the same optical paths as the pump beams …

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Optical Characterization Of Antimony-Based, Types-I And Ii, Multiple Quantum-Well Semiconductor Structures For Mid-Infrared Laser Applications, Edward G. Ferguson Mar 2003

Optical Characterization Of Antimony-Based, Types-I And Ii, Multiple Quantum-Well Semiconductor Structures For Mid-Infrared Laser Applications, Edward G. Ferguson

Theses and Dissertations

This experiment characterizes antimony-based, multiple quantum-well, types-I and -II, semiconductor samples designed for laser applications. The samples emit light in the 3-5-micron range to exploit an atmospheric transmission window, making them ideal for infrared (IR)-seeking missile countermeasures. Photoluminescence (PL) spectra were collected and yielded bandgap (E(sub g)) dependence-on-temperature relationships. The type-I sample was found to follow the Varshni equation, while the type-II samples showed a rise with temperature in a portion of the curve that should be linear according to the Varshni equation. The type-II samples followed the Varshni equation well at higher temperature. The PL study indicated that the …

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A Simulation-Based Analysis Of The Impact Of In-Sourcing A Major Process Element On The Coast Guard Hh-601 Depot Maintenance Process, Steven E. Vigus Mar 2003

A Simulation-Based Analysis Of The Impact Of In-Sourcing A Major Process Element On The Coast Guard Hh-601 Depot Maintenance Process, Steven E. Vigus

Theses and Dissertations

Leaders at the United States Coast Guard's Aircraft Repair and Service Center (ARSC) in Elizabeth City, North Carolina recently formalized their planning and analysis functions by adding a dedicated branch to their command structure. The Planning and Analysis Branch intends to apply computer modeling and simulation to study the impact of process changes to the various Programmed Depot Maintenance (PDM) lines. This research considers the applicability of this type of modeling and simulation, using ARENA to study the current HH-6OJ PDM process. The contribution of this research is a methodology specific to ARSC needs, an analysis of methodology based on …

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Assessing Organization Culture Readiness For Knowledge Management Implementation: The Case Of Aeronautical Systems Center Directorate Of Contracting, Martin R. Trent Mar 2003

Assessing Organization Culture Readiness For Knowledge Management Implementation: The Case Of Aeronautical Systems Center Directorate Of Contracting, Martin R. Trent

Theses and Dissertations

The DoD is currently pursuing a wholesale transformation that impacts all facets of DoD operations and responsibilities. At the same time, the commercial sector has been experiencing significant changes that drive them to look for new ways of remaining competitive and profitable. Leveraging knowledge (intellectual capital) to increase efficiency and effectiveness within the organization has become a popular management technique that has been successful in many commercial firms. The DoD has noted the commercial sector successes and initiatives to better manage knowledge are being developed and implemented on an enterprise-wide basis as well as on a local- organizational basis. Previous …

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Evaluation Of Personnel Parameters In Software Cost Estimating Models, Steven L. Quick Mar 2003

Evaluation Of Personnel Parameters In Software Cost Estimating Models, Steven L. Quick

Theses and Dissertations

Software capabilities have steadily increased over the last half century. The Department of Defense has seized this increased capability and used it to advance the warfighter's weapon systems However, this dependence on software capabilities has come with enormous cost. The risks of software development must be understood to develop an accurate cost estimate.

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A Visual Language For Composable Simulation Scenarios, Carolyn R. Bartley Mar 2003

A Visual Language For Composable Simulation Scenarios, Carolyn R. Bartley

Theses and Dissertations

Modeling and Simulation plays an important role in how the Air Force trains and fights, Scenarios are used in simulation to give users the ability to specify entities and behaviors that should be simulated by a model: however, building and understanding scenarios can be a difficult and time-consuming process, furthermore, as composable simulations become more prominent, the need for a common descriptor for simulation scenarios has become evident. In order to reduce the complexity of creating and understanding simulation scenarios, a visual language was created, The research on visual languages presented in this thesis examines methods of visually specifying the …

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Reverse Geographic Location Of A Computer Node, Clinton G. Carr Iii Mar 2003

Reverse Geographic Location Of A Computer Node, Clinton G. Carr Iii

Theses and Dissertations

The determination of methods by which a user is able to locate his computer when that user does not know his current location, termed "homestation", will provide the Air Force an advantage over its adversaries. The methods are a combination of different mathematical techniques that enable the user to manipulate data to minimize the effects of delay caused by various factors on the network. The techniques use the smallest round trip time obtained from the ping utility. This time is then converted into miles and plotted on a map of the United States. The methods used to solve this problem …

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Distributed Control Of A Swarm Of Autonomous Unmanned Aerial Vehicles, James T. Lotspeich Mar 2003

Distributed Control Of A Swarm Of Autonomous Unmanned Aerial Vehicles, James T. Lotspeich

Theses and Dissertations

With the increasing use of Unmanned Aerial Vehicles (UAV)s military operations, there is a growing need to develop new methods of control and navigation for these vehicles. This investigation proposes the use of an adaptive swarming algorithm that utilizes local state information to influence the overall behavior of each individual agent in the swarm based upon the agent's current position in the battlespace. In order to investigate the ability of this algorithm to control UAVs in a cooperative manner, a swarm architecture is developed that allows for on-line modification of basic rules. Adaptation is achieved by using a set of …

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Uml Assisted Visual Debugging For Distributed Systems, Benjamin R. Musial Mar 2003

Uml Assisted Visual Debugging For Distributed Systems, Benjamin R. Musial

Theses and Dissertations

The DOD is developing a Joint Battlespace Infosphere, linking a large number of data sources and user applications. To assist in this process, debugging and analysis tools are required. Software debugging is an extremely difficult cognitive process requiring comprehension of the overall application behavior, along with detailed understanding of specific application components. This is further complicated with distributed systems by the addition of other programs, their large size and synchronization issues. Typical debuggers provide inadequate support for this process, focusing primarily on the details accessible through source code. To overcome this deficiency, this research links the dynamic program execution state …

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An Artificial Immune System Strategy For Robust Chemical Spectra Classification Via Distributed Heterogeneous Sensors, Mark A. Esslinger Mar 2003

An Artificial Immune System Strategy For Robust Chemical Spectra Classification Via Distributed Heterogeneous Sensors, Mark A. Esslinger

Theses and Dissertations

The timely detection and classification of chemical and biological agents in a wartime environment is a critical component of force protection in hostile areas. Moreover, the possibility of toxic agent use in heavily populated civilian areas has risen dramatically in recent months. This thesis effort proposes a strategy for identifying such agents vis distributed sensors in an Artificial Immune System (AIS) network. The system may be used to complement "electronic" nose ("E-nose") research being conducted in part by the Air Force Research Laboratory Sensors Directorate. In addition, the proposed strategy may facilitate fulfillment of a recent mandate by the President …

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Using Future Value Analysis To Select An Optimal Portfolio Of Force Protection Initiatives, Robert P. Eskridge Mar 2003

Using Future Value Analysis To Select An Optimal Portfolio Of Force Protection Initiatives, Robert P. Eskridge

Theses and Dissertations

With the recent increase in terrorist activity, force protection has become a key issue for the Department of Defense, Leading the research for new ideas and concepts in force protection for the US Air Force is the Air Force Force Protection Battlelab (FPB). The FPB is charged with searching out force protection ideas and selecting those most worthy for future consideration. In 2002, a Value-Focused Thinking (VFT) hierarchy was created to help the FPB select those ideas that provided the most value to the Air Force and its force protection goals. This research effort uses the Future Value Analysis (FVA) …

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Modeling Catalytic Destruction Of Subsurface Contaminants In Recirculating Wells, Kerry J. Cadena Mar 2003

Modeling Catalytic Destruction Of Subsurface Contaminants In Recirculating Wells, Kerry J. Cadena

Theses and Dissertations

Groundwater and soil contamination is a significant problem throughout the nation, with approximately 300,000 to 400,000 sites affected (National Research Council, 1994). Examples of groundwater contaminants of special interest to DoD and AF installations include fuel hydrocarbons, chlorinated hydrocarbons, and nitroaromatic compounds. Traditional remediation technologies, which include pump-and-treat, permeable reactive barriers, and natural attenuation, have numerous drawbacks associated with them. These drawbacks have prompted researchers to look for innovative contamination clean-up methods. The technology investigated in this thesis, reticulating horizontal flow treatment wells (HFTWs) with in-well palladium (Pd) catalyst reactors, offers the potential for destruction of groundwater contaminants commonly found …

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An Economic Evaluation Of Binary Cycle Geothermal Electricity Production, Crissie D. Fitzgerald Mar 2003

An Economic Evaluation Of Binary Cycle Geothermal Electricity Production, Crissie D. Fitzgerald

Theses and Dissertations

The U.S. is heavily dependent on fossil fuels to produce electricity. Geothermal energy, the heat in the earth's crust, can provide an alternative source of energy for electricity production as well as reduce fossil fuel consumption. The economic analysis presented in this study focuses on binary cycle geothermal electricity production. Variables such as well flow rate, geothermal gradient and electricity prices were varied to study their influence on the economic payback period for binary cycle geothermal electricity production. Payback periods represent the amount of time (in years) necessary to recover initial costs of plant construction.

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Understanding The Dynamic System Of Terrorist - Government Interaction, John A. Hanrahan Mar 2003

Understanding The Dynamic System Of Terrorist - Government Interaction, John A. Hanrahan

Theses and Dissertations

The nature of action and reaction that forms the basis for terrorist - government interactions creates a dynamic system. Understanding how this dynamic system behaves in response to key government activities can help the government better control the overall behavior of the system. The system dynamics methodology is one tool that can help the government solve specific behavioral problems within the overall system. This research shows the ability of system dynamics to help develop government policy towards terrorism that can directly affect a terrorist's behavior. It supports a government policy of offensive action instead of defensive reaction. It also identifies …

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A Life Cycle Assessment And Economic Analysis Of Wind Turbines Using Monte Carlo Simulation, Edward J. Liberman Mar 2003

A Life Cycle Assessment And Economic Analysis Of Wind Turbines Using Monte Carlo Simulation, Edward J. Liberman

Theses and Dissertations

The United States depends heavily on nonrenewable fossil fuels to generate electricity. Using renewable energy sources, such as wind, could reduce air emissions and fossil fuel dependency. Previous studies have examined the life cycle costs and environmental impacts of using wind to generate electricity, but results have varied due to inconsistent modeling assumptions. This research uses Monte Carlo simulation to conduct an economic payback analysis and life cycle assessment of 11 modern, utility-scale wind turbines. Hourly meteorological data was used to evaluate 239 U.S. locations. For each location, the wind turbine with the shortest median payback period was assumed to …

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Remote Sensing Systems Optimization For Geobase Enhancement, Steve J. Paylor Mar 2003

Remote Sensing Systems Optimization For Geobase Enhancement, Steve J. Paylor

Theses and Dissertations

The U.S. Air Force is in the process of implementing GeoBase, a geographic information system (GIS), throughout its worldwide installations, Air Force GIS needs can be augmented by imagery from aerial and satellite platforms. Imagery has greatly improved over the past several years and provides high resolution coverage of features on earth. Various imagery types will significantly increase GeoBase usefulness in a range of mission requirements, Potential Air Force uses of imagery include identifying heat loss, environmental monitoring, command decision-making, and emergency response, The research develops a decision tool to determine the appropriate imagery for a given Air Force Application, …

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Palladium-Catalyzed Destruction Of Nitro Aromatic-Contaminated Groundwater, Dennis Landon Phillips Mar 2003

Palladium-Catalyzed Destruction Of Nitro Aromatic-Contaminated Groundwater, Dennis Landon Phillips

Theses and Dissertations

Of the over 17,000 DoD sites that potentially require remediation, sites containing soil and groundwater contaminated by energetic compounds are prevalent (Larson et al., 2001). Production of energetics such as 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5 - trinitro- 1,3,5 -triazine (RDX), and octahydro-1,3,5,7-tetranitro- 1,3,5,7-tetrasocine (HMX) for use in munitions has created a DoD-wide problem due to improper disposal techniques (Price et al., 2001), Nitro aromatic compounds (NACs) similar to those used in explosives can also be found in insecticides, herbicides, pharmaceuticals, dyes, plastics, and many other commonly used products. The natural breakdown of these contaminants creates byproducts such as amines, which are known …

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Theoretical Analysis Of Information Watermarking In Wavelet-Based Video Compression, Brendan K. Casey Mar 2003

Theoretical Analysis Of Information Watermarking In Wavelet-Based Video Compression, Brendan K. Casey

Theses and Dissertations

Embedding audio bits into images for transmission of video data alleviates the synchronization problem common in video transmission techniques. We continue work combining audio or other information bits and images into one file using digital watermarking techniques to correct the synchronization problem. The system compresses the file by using wavelet image coefficients and implementing bit plane coding. Our research encompasses incorporating five free variables into the watermark/compression technique. These variables are watermark robustness, number of coding iterations, number of image coefficients, number of watermarked information bits, and number of watermarked error correcting bits. By altering these variables, four measurements of …

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Ultra Wide Band Multiple Access Performance Using Th-Ppm And Ds-Bpsk Modulations, Courtney M. Canadeo Mar 2003

Ultra Wide Band Multiple Access Performance Using Th-Ppm And Ds-Bpsk Modulations, Courtney M. Canadeo

Theses and Dissertations

The increasing demand for portable, high data rate communications has focused much attention on wireless technology. Ultra Wide Band (UWB) waveforms have the ability to deliver megabits of information while maintaining low average power consumption. In accordance with recent FCC ruling, UWB systems are now allowed to operate in the unlicensed spectrum of 3.1 to 10.6 GHz, motivating renewed interest in the forty year old concept of impulse radio. Gaussian monocycles produce UWB waveforms occupying large bandwidths with multiple access (MA) capability enabled by spread spectrum techniques. Time Hopping (TH) and Direct Sequence (DS) modulations are considered here for UWB …

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Using The Gps To Improve Trajectory Position And Velocity Determination During Real-Time Ejection Seat Design, Test And Evaluation, Christina G. Schutte Mar 2003

Using The Gps To Improve Trajectory Position And Velocity Determination During Real-Time Ejection Seat Design, Test And Evaluation, Christina G. Schutte

Theses and Dissertations

Test and evaluation of the United States Air Force’s latest aircraft escape system technology requires accurate position and velocity profiles during each test to determine the relative positions between the aircraft, ejection seat, manikin and the ground. Current rocket sled testing relies on expensive ground based multiple camera systems to determine the position and velocity profiles. While these systems are satisfactory at determining seat and manikin trajectories for sled testing, their accuracy decreases when they are used for in-flight testing, especially at high altitudes. This research presents the design and test results from a new GPS-based system capable of monitoring …

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Ins Aiding Using Passive, Bearings-Only Measurements Of An Unknown Stationary Ground Object, Alec E. Porter Mar 2003

Ins Aiding Using Passive, Bearings-Only Measurements Of An Unknown Stationary Ground Object, Alec E. Porter

Theses and Dissertations

The theory for Inertial Navigation System (INS) aiding using passive, bearings only measurements of an unknown stationary ground object, in the vein of optical flow measurement, is developed. Stand-alone bearings-only measurements over time of an unknown, but stationary, ground object are shown to yield estimates of the aircraft’s aerodynamic angles, viz., the angle of attack and sideslip angle. Two new equations containing the aircraft’s angular navigation variables ψ, θ, φ, γ, H, and the aerodynamic angles are derived. This allows an update of the aircraft’s attitude, thus making INS aiding using passive, bearings-only measurements possible. Moreover, the use of stadiametry, …

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Development Of A Simplified Sustainable Facilities Guide, David F. Hargy Mar 2003

Development Of A Simplified Sustainable Facilities Guide, David F. Hargy

Theses and Dissertations

The Air Force has adopted the United States Green Building Council's Leadership in Energy and Environmental Design (LEED™) Green Building Rating System as the preferred self-assessment metric for sustainable development. LEED™ is designed for new construction and major renovations, and, within the Air Force, is most applicable for Military Construction (MILCON) projects. The Air Force Center for Environmental Excellence developed the Air Force Sustainable Facilities Guide to provide guidance and strategies to meet LEED™ requirements. The Air Force has not adopted a sustainable development guide or rating system that is most applicable for construction projects that are relatively low (compared …

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Gaussian Mixture Reduction Of Tracking Multiple Maneuvering Targets In Clutter, Jason L. Williams Mar 2003

Gaussian Mixture Reduction Of Tracking Multiple Maneuvering Targets In Clutter, Jason L. Williams

Theses and Dissertations

The problem of tracking multiple maneuvering targets in clutter naturally leads to a Gaussian mixture representation of the Provability Density Function (PDF) of the target state vector. State-of-the-art Multiple Hypothesis Tracking (MHT) techniques maintain the mean, covariance and probability weight corresponding to each hypothesis, yet they rely on ad hoc merging and pruning rules to control the growth of hypotheses.

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Development Of Variable Slope Piecewise-Based Brown Symbols For Application To Nonlinear Ambiguity Suppression, John Kurian Mar 2003

Development Of Variable Slope Piecewise-Based Brown Symbols For Application To Nonlinear Ambiguity Suppression, John Kurian

Theses and Dissertations

In 1962, Palermo used two conjugate Linear Frequency Modulated (LFM) pulses to demonstrate a Non-linear Ambiguity Suppression (NLAS) technique to reduce ambiguous energy in radar returns. Using conjugate LFM pulse coding does not readily extend to larger symbol families and thus is severely limited for M-channel (M> 2) NLAS applications. Larger families of optimal mutually dispersible codes with bigger time bandwidth products are needed to achieve the desired M-fold range ambiguity reduction. Using correlation function the time duration as an optimization metric, the recently proposed Brown's theorem formulates a deterministic process for designing optimal mutually dispersible symbol sets of arbitrary …

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Combining And Analyzing The Tanker And Aircrew Scheduling Heuristics, Cem Boke Mar 2003

Combining And Analyzing The Tanker And Aircrew Scheduling Heuristics, Cem Boke

Theses and Dissertations

Air refueling is an integral part of U.S. air power across a wide range of military operations. It is an essential capability in the conduct of air operations worldwide and is especially important when overseas basing is limited or not available. The planning, tasking, and scheduling of aerial refueling require solution of two major problems: assigning and scheduling of tankers to refueling points and efficiently assigning crews to each tanker. To address the scheduling of tankers, Wiley (2001) developed an efficient tabu search approach. Combs (2002) developed another tabu search approach to assign crews to tankers. This research combines the …

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Analysis Of Scheduling Policies For A M/G/I Queue With Rework, Jennifer Hendrixson Mar 2003

Analysis Of Scheduling Policies For A M/G/I Queue With Rework, Jennifer Hendrixson

Theses and Dissertations

This thesis analyzes a multi-class M/G/1 priority queueing system in which distinct job types require one service cycle and, with non-zero probability, require a second service cycle. The main objective is to find a new heuristic scheduling policy that minimizes the long-run expected holding and preemption costs. Arrival rates, service rates, and the probability of undertaking second service are all class specific. A mean value analysis (MVA) approach was employed to derive the long- run mean time in queue for each job type under each policy, thereby providing the appropriate cost equations. Numerical experiments suggest that the preemptive resume scheduling …

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Game Theory And U-Boats In The Bay Of Biscay, Joseph C. Price Mar 2003

Game Theory And U-Boats In The Bay Of Biscay, Joseph C. Price

Theses and Dissertations

Analysis of a large combat campaign using game theory is difficult due to non- linearities and other soft factors which exist in a complex system. However, game theory can give decision makers insight into strategies and outcomes that can be utilized to maximize one's objective. Agent-based simulation provides the means to model complex systems with non-linearities, by allowing for interactions among independent "agents." This thesis investigates game-theoretic strategies in agent-based simulation, modeled after the Allied search for U-boats in the Bay of Biscay during World War II (WWII). It also looks into the effects of adaptation on strategies by comparison …

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Optimal Replacement Policies For Satellite Constellations, Bradley R. Sumter Mar 2003

Optimal Replacement Policies For Satellite Constellations, Bradley R. Sumter

Theses and Dissertations

This work considers the problem of finding optimal replacement policies that minimize the expected total cost of maintaining a satellite constellation. The problem is modeled using discrete-time Markov decision processes to determine the replacement policy by allowing the satellite constellation to be in one of a finite number of states at each decision epoch. The constellation stochastically transitions at each time step from one state to another as determined by a set of transition probabilities. At each decision epoch, a decision maker chooses an action from a set of allowable actions for the current system state. A cost associated with …

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