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Prototype Development And Dynamic Characterization Of Deployable Cubesat Booms, Grant M. Thomas
Prototype Development And Dynamic Characterization Of Deployable Cubesat Booms, Grant M. Thomas
Theses and Dissertations
The current barrier to CubeSat proliferation is their lack of utility depth. These small satellites are exceptionally well suited for specific space missions such as space weather observation and other scientific data gathering exploits; however, they are not suited for every mission. The 10cm-cube form factor that gives the CubeSat its unique advantage is also its greatest hindrance. A potential bridge over this gap is the successful integration of deployable booms onto the CubeSat structure. With this research, the Air Force Institute of Technology (AFIT) explored the parameters of deployable tapespring booms using the triangular retractable and collapsible (TRAC) cross- …
Minimizing Losses In A Space Laser Power Beaming System, Charlie T. Bellows
Minimizing Losses In A Space Laser Power Beaming System, Charlie T. Bellows
Theses and Dissertations
A mathematical model is developed to track the amount of power delivered in a wireless laser power beaming system. In a wireless system the power proceeds through several different stages before being delivered to a payload for use. Each of these stages results in power losses that are thoroughly examined and modeled, allowing for the calculation of the likely amount of power delivered. Adjusting variable factors within the model allows for the optimization of the system for a specific task. The model shows that an optimized wireless power transfer system can deliver enough power to meet the space experiment objectives. …
Development Of A Remotely Operated Autonomous Satellite Tracking System, Michael E. Graff
Development Of A Remotely Operated Autonomous Satellite Tracking System, Michael E. Graff
Theses and Dissertations
AFIT is currently developing a capability to remotely and autonomously track LEO satellites using commercial telescopes. Currently, the system is capable of open-loop tracking based on Two-Line Element sets (TLEs) downloaded from NORAD’s space object catalog. The ability to actively track using a closed-loop control system would allow tracking of satellites which deviated from the published TLEs along with providing some information about the object’s new orbital elements. To accomplish closed-loop tracking, the object is imaged by a digital camera connected to a wide field-of-view (WFOV) spotting scope. Software was developed to provide azimuth and elevation inputs in order to …
Analysis Of Slewing And Attitude Determination Requirements For Ctex, William J. Starr Jr.
Analysis Of Slewing And Attitude Determination Requirements For Ctex, William J. Starr Jr.
Theses and Dissertations
This thesis examines the slewing and attitude determination requirements for the Chromotomographic Experiment (CTEX), a chromotomographic-based hyperspectral imager, to be mounted on-board the Japanese Experiment Module (JEM) External Facility (EF). The in-track slewing requirement is driven by the facts that CTEx has a very small field of view (FOV) and is required to collect 10 seconds of data for any given collection window. The need to slew in the cross-track direction is a product of the small FOV and target/calibration site access. CTEx incorporates a two-axis slow-steering dwell mirror with a range of ± 8 degrees and an accuracy of …
Mission Analysis For Multiple Rendezvous Of Near-Earth Asteroids Using Earth Gravity Assist, Uriah J. Tobey
Mission Analysis For Multiple Rendezvous Of Near-Earth Asteroids Using Earth Gravity Assist, Uriah J. Tobey
Theses and Dissertations
The Jet Propulsion Laboratory (JPL) catalog of near-Earth objects (NEOs) such as asteroids and comets contains over 6600 asteroids and 150 comets as of February of 2010. This includes over 1000 potentially hazardous asteroids, or objects with orbits that pass close enough to Earth to pose a potential impact threat. The asteroid community believes there are a significant number of objects still undiscovered, which makes finding, tracking, and calculating missions to study these objects an active area of research. This study was based on finding orbit solutions using Earth gravity assist to visit one near-Earth object (NEO) a year for …
A Linear Programming Approach For Determining Travel Cost Minimizing Ecss Training Locations, Jason S. Boerboom
A Linear Programming Approach For Determining Travel Cost Minimizing Ecss Training Locations, Jason S. Boerboom
Theses and Dissertations
The Department of Defense is currently operating in a fiscally constrained environment, and Air Force leaders are pressured to minimize spending while pursuing mission critical objectives. Personnel travel usurps a significant portion of the Air Force’s annual operations and maintenance (O&M) budget each year, but receives little attention with respect to cost saving strategies. During the Air Force’s implementation of the Expeditionary Combat Support System (ECSS), in which over 250,000 end-users will require training, it is vital that the Department determine the training locations that minimize costs incurred through personnel travel. This thesis seeks to determine which potential ECSS training …
A Simulation Based Methodology To Examine The B-1b'S An/Alq-161 Maintenance Process, Ricardo R. Garza
A Simulation Based Methodology To Examine The B-1b'S An/Alq-161 Maintenance Process, Ricardo R. Garza
Theses and Dissertations
The B-1 Bomber is the Air Force’s only supersonic, conventional-only strike platform. This thesis looks at the maintenance procedures associated with the defensive electronic counter measure (ECM) system on the B-1B, designated the AN/ALQ-161. Computer simulation of the current line-replaceable-unit maintenance network for Ellsworth AFB and Dyess AFB is modeled. In addition, two hypothetical repair networks are proposed and analyzed. This research considers the applicability of this type of computer simulation, using ARENA software to study the AN/ALQ-161 repair system. The contribution of this research is a discrete simulation methodology specific to the AN/ALQ-161 LRU repair line. Two response variables …
Stealthy River Navigation In Jungle Combat Conditions, Fabio Ayres Cardoso
Stealthy River Navigation In Jungle Combat Conditions, Fabio Ayres Cardoso
Theses and Dissertations
One of the biggest challenges for Brazilian military logisticians is to support effective jungle warfare for both real and training operations carried out by their combat forces in the Amazonian region. The jungle's heat, humidity, and dense vegetation put significant demands on the supply chain. Further, because of the difficulties of land or air transportation, water transport is the most reasonable transportation option to sustain these deployed forces. Planners must select from among the available watercourses those whose surroundings provide stealthy navigation to the combat force location where the requested supplies can be safely unloaded. We seek a method of …
Fuel Efficiency Assessment With Dea, Evren Kiymaz
Fuel Efficiency Assessment With Dea, Evren Kiymaz
Theses and Dissertations
In this study, Data Envelopment Analysis (DEA) is used to calculate Air Mobility Command (AMC) airlift fuel efficiency for C-17 aircraft. Fuel is a strategic asset for the United States Air Force and suitable alternatives are not yet feasible or available in the quantity required. The Air Force is pursuing several initiatives to conserve energy and operate more efficiently while sustaining the same level of effectiveness and safety. In order to manage these initiatives, it must measure how well it is doing. To measure airlift efficiency, the AMC Fuel Efficiency Office established a 7 factor weighted Fuel Efficiency Index (FEI). …
Assessing Resilience In Power Grids As A Particular Case Of Supply Chain Management, Gabriel Alejandro Montoya
Assessing Resilience In Power Grids As A Particular Case Of Supply Chain Management, Gabriel Alejandro Montoya
Theses and Dissertations
Electrical power grids represent a critical infrastructure for a nation as well as strategically important. Literature review identified that power grids share basic characteristics with Supply Chain Management. This thesis presents a linear programming model to assess power grid resilience as a particular case of Supply Chain Management. Since resilient behavior is not an individual or specific system's attribute but a holistic phenomenon based on the synergic interaction within complex systems, resilience drivers in power grids were identified. Resilience is a function of Reliability, Recovery Capability, Vulnerability and Pipeline Capacity. In order to embed heterogeneous variables into the model, parameterization …
Fuel Savings Opportunities From Air Refueling, Murat Toydas
Fuel Savings Opportunities From Air Refueling, Murat Toydas
Theses and Dissertations
Fuel is a critical strategic asset for military aviation operations, yet is increasingly expensive. Air refueling offers both the opportunity to extend aircraft range and the potential to save fuel by enabling a transport aircraft to depart with less fuel in exchange for additional cargo. We evaluate the practicality of air refueling in terms of fuel savings versus distance and cargo quantity, by introducing two non-linear optimization models that examine the tradeoff between departure fuel weight and loaded cargo for given origin, destination, and tanker base positions and freight quantities to be moved. We use various numerical example scenarios to …
Maximizing Strike Planning Efficiency For A Given Class Of Targets, Necip Dirik
Maximizing Strike Planning Efficiency For A Given Class Of Targets, Necip Dirik
Theses and Dissertations
Strike planning is one of the fundamental tasks of the Turkish Air Force and involves assignment of strike aircraft to targets with a maximum level of efficiency. Therefore, planning an optimal strike plan based on the preferences of the decision maker is crucial. The efficiency of the strike plan in this research implies attacking the maximum number of targets while considering target priority and the desired level of damage on each target. Another objective is to minimize the cost of the plan. This research develops an exact model that maximizes the efficiency of the strike plan using LINGO with Excel …
The Uav Continuous Coverage Problem, Taegyun Ha
The Uav Continuous Coverage Problem, Taegyun Ha
Theses and Dissertations
The purpose of this research is to develop a method to find an optimal UAV cyclic schedule to provide maximum coverage over a target area to support an ISR mission. The goal is to reach continuous coverage. UAV continuous coverage of a target area is crucial for the success of an ISR mission. Even the smallest coverage gap may jeopardize the success of the mission. Ideally it is desirable to obtain continuous coverage of a target area but the stochastic nature of the problem makes continuous coverage without gaps unlikely. However, it is still possible to obtain a high coverage …
A Multi-Objective Approach To A Bipartite Assignment Matching Problem Using Weighted Values From Multiple Contraints, Greg S. Jeong
A Multi-Objective Approach To A Bipartite Assignment Matching Problem Using Weighted Values From Multiple Contraints, Greg S. Jeong
Theses and Dissertations
US Air Force recruiters routinely assign new recruits to available jobs every month. The goal is to find the best assignments in an efficient manner. Although this problem is modeled as a bipartite assignment matching problem, it is not new to the field of Operations Research. This research presents a new approach to solve assignment matching problems given multiple side constraints. Using two multi-criteria optimization techniques, lexicographic optimization and the elastic constraint method, the assignment matching algorithm efficiently produces an optimal solution in a fraction of the time currently spent. This approach is demonstrated in assigning new USAF recruits to …
An Exploration Of The Effects Of Maintenance Manning On Combat Mission Readiness Utilizing Agent Based Modeling, Adam S. Mackenzie
An Exploration Of The Effects Of Maintenance Manning On Combat Mission Readiness Utilizing Agent Based Modeling, Adam S. Mackenzie
Theses and Dissertations
Agent based models have been shown to be powerful tools in describing processes and systems centered on individual behaviors and local interactions (i.e. “bottom-up”) between specific entities. Current application areas tend to be focused within the business and social science arenas, although their usefulness has been demonstrated in the modeling of various chemistry and physics-based systems. Conversely, many highly process-oriented systems, such as manufacturing environments, tend to be modeled via “top-down” methods, including discrete or continuous event simulations among others. As a result, potentially critical attributes of the entities or resources modeled with these methods (spatial properties, “learning curve” or …
Simulation Analysis Of High Velocity Maintenance For The B-1b, Anson R. Park
Simulation Analysis Of High Velocity Maintenance For The B-1b, Anson R. Park
Theses and Dissertations
This thesis explores the impact that High Velocity Maintenance (HVM) will have on aircraft availability rates for the B-1B by examining the proposed changes to the field maintenance and supply processes for the two B-1B squadrons of the 28th Bombardment Wing located at Ellsworth AFB, SD. There is a significant restructuring of depot level maintenance planned with the implementation of HVM, and the impact that this will have on base-level operations is important to determine, for it will provide insight as to whether or not HVM will be a feasible program with a high probability of successfully improving B-1B aircraft …
Optimizing An F-16 Squadron Weekly Pilot Schedule For The Turkish Air Force, Murat Yavuz
Optimizing An F-16 Squadron Weekly Pilot Schedule For The Turkish Air Force, Murat Yavuz
Theses and Dissertations
Fighter squadrons in the Turkish Air Force build flight schedules for weekly periods. This process requires a great deal of time and does not seek optimality. Schedules are built with feasibility concerns. The Turkish Air Force doesn’t have an automated tool for flight scheduling. Many constraints including crew rest, number of sorties flown in a month, and duty currencies affect the schedule. Providing an automated scheduling tool may help schedulers save time for other squadron tasks including mission preparation, briefing, and debriefing. In this research, a heuristic approach to the problem is developed. Greedy Randomized Adaptive Search Procedures (GRASP) is …
Screening And Sufficiency In Multiobjective Decision Problems With Large Alternative Sets, Michael D. Cote
Screening And Sufficiency In Multiobjective Decision Problems With Large Alternative Sets, Michael D. Cote
Theses and Dissertations
Portfolio selection problems with combinatorially-large alternative sets can be impossible to evaluate precisely on a reasonable timescale. When portfolios require complex modeling for performance assessment, prohibitive computational processing times can result. Eliminating a small number of alternatives through an intelligent screening process can greatly reduce the number of alternative combinations, thereby decreasing a problem's evaluation time and cost. A methodology was developed for the class of hierarchical portfolio selection problems in which multiple objectives are all judged on the same sub-objectives. First, a novel capability-based alternative screening process was devised to identify and remove poor alternatives, thereby reducing the number …
Development Of Measures To Assess Product Modularity And Reconfigurability, Amie C. Stryker
Development Of Measures To Assess Product Modularity And Reconfigurability, Amie C. Stryker
Theses and Dissertations
Several fundamental benefits of modularity are agreed upon by industry including reusability, flexibility, reconfigurability and extensibility. Interfaces within or between modules which establish provide/depend relationships are the focus of current modularity measures. This research outlines a new method and measures for assessing product modularity in terms of degree of coupling and the recognized modularity benefits. A five–step analysis process is developed and used to guide the modularity assessment. Defining and decomposing products are performed first. Using the resultant functional model from the first step, the identified functions are mapped to modules in a product in the second step. In the …
An Evaluation Of Compressed Work Schedules And Their Impact On Electricity Use, Ryan R. Archambault-Miliner
An Evaluation Of Compressed Work Schedules And Their Impact On Electricity Use, Ryan R. Archambault-Miliner
Theses and Dissertations
As the largest energy consumer in the United States, the Department of Defense must consider all fiscally responsible means to improve energy efficiency. Budgetary and environmental concerns are a catalyst for numerous initiatives designed to reduce energy consumption. Congressional mandates outline the rate at which agencies must reduce facility energy use. In this study, Monte Carlo simulation was used to compare electricity consumption, cost, and emissions produced under 5-day workweeks and compressed work schedules. The research provides energy managers a template for evaluating compressed work schedules as a means to improve energy efficiency. The study found the relationship between the …
Optimizing Aircraft Availability: Where To Spend Your Next O&M Dollar, Frederick G. Fry
Optimizing Aircraft Availability: Where To Spend Your Next O&M Dollar, Frederick G. Fry
Theses and Dissertations
In the current fiscally constrained environment, the Air Force must allocate resources where they are most needed and will be most effectively used. For aircraft, this means spending money on weapon systems in a manner that optimizes aircraft availability rates, thereby maximizing the warfighting capability of the Air Force. With that in mind, this thesis endeavors to improve the analytical capability of the Air Force by demonstrating a definitive link between operations and maintenance (O&M) spending and aircraft availability rates. In order to do that, explanatory regression models are developed that show the relationship between O&M spending and AA rates, …
Evaluation Of Cost Improvement Models When Programs Experience Unplanned Production Decreases, Anthony R. George
Evaluation Of Cost Improvement Models When Programs Experience Unplanned Production Decreases, Anthony R. George
Theses and Dissertations
As military and other governmental budgets decline and impacted project deadline changes require instantaneous responses, cost analysts' tasks become more and more formidable. Inaccurate estimates can lead to misappropriation of resources and can thus create delays in goods reaching warfighters. This thesis aims to avail cost estimators of more reliable projection tools and to challenge the status quo of cost estimating, the production rate cost improvement model, when programs face reductions in lot quantities. The findings reveal that the status quo proves efficient under many cost profiles, but clearly does not estimate as well when a program suffers lot quantity …
Assessing The Economic And Environmental Impacts Associated With Current Street Lighting Technologies, Carlos J. Colon Jr.
Assessing The Economic And Environmental Impacts Associated With Current Street Lighting Technologies, Carlos J. Colon Jr.
Theses and Dissertations
Rising global energy demand and natural disasters continuously threaten energy supplies and prices. As a result, the U.S. government has mandated all government agencies to reduce energy consumption in order to minimize dependence on foreign energy supply and reduce costs. Concern over carbon emissions and environmental impacts has also been expressed in these mandates. One solution may be to invest in newer lighting technologies, such as light-emitting diode (LED) and electrodeless induction, in order to reduce the energy consumption, environmental impact, and costs required for both exterior roadway and parking lot lighting applications. This research compared these lighting technologies with …
Environmental Life Cycle Assessment Of Coal-Biomass To Liquid Jet Fuel Compared To Petroleum-Derived Jp-8 Jet Fuel, Wayne C. Kinsel
Environmental Life Cycle Assessment Of Coal-Biomass To Liquid Jet Fuel Compared To Petroleum-Derived Jp-8 Jet Fuel, Wayne C. Kinsel
Theses and Dissertations
The United States (U.S.) imported 57% of the petroleum products that it consumed in 2008. The Department of Defense (DOD) and in particular, the United States Air Force (USAF), consumes a large amount of oil to support the mission of defending the U.S. According to the USAF energy policy, by 2016, the Air Force (AF) must be prepared to cost competitively acquire 50% of its domestic aviation fuel requirement via an alternative fuel blend in which the alternative component is derived from domestic sources produced in a manner that is “greener” than fuels produced from conventional petroleum. This study employed …
A Study Of The Relationship Between Proenvironmental Product Use And Environmnetal Concern, Joshua M. Poulton
A Study Of The Relationship Between Proenvironmental Product Use And Environmnetal Concern, Joshua M. Poulton
Theses and Dissertations
To be sustainable, an organization must be balanced in the three principles of economy, environment, and society. Advances in pro-environmental technology have overcome roadblocks limiting the economic and environmental principles. The remaining hurdle to becoming sustainable is having society’s beliefs and behaviors align. Understanding the interaction between an individual’s environmental belief and environmental behaviors is essential to bringing them into alignment. To explore this relationship, a model was developed that included the new ecological paradigm (NEP) scale and a generalized version of the theory of planned behavior (TPB). The attitudes, intentions, and use of six pro-environmental products were measured in …
Security Vulnerability Trends Related To Electric Power Supplied At Military Installations, Peter A. Sabatowski
Security Vulnerability Trends Related To Electric Power Supplied At Military Installations, Peter A. Sabatowski
Theses and Dissertations
The United States (U.S.) electric grid is considered one of the greatest inventions of the twentieth century, yet it become apparent over the past few decades that it is not without its own set of problems. The deregulation of the U.S. electric system in the late 1990s eliminated monopolies and resulted in the nation's generation, transmission, and distribution systems becoming separate entities owned and operated by multiple companies. This created a market economy in which many electric companies failed to plan for the future, did not invest in maintenance and upgrades, and began to push the aggregate system to its …
Evaluation Of Alternative Technologies To Supply Drinking Water To Marines In Forward Deployed Locations, Derek R. George
Evaluation Of Alternative Technologies To Supply Drinking Water To Marines In Forward Deployed Locations, Derek R. George
Theses and Dissertations
With recent increases, there are approximately 20,000 Marines deployed in the Helmand Province of Afghanistan. The cost of delivering bottled water to the troops is rapidly becoming unsustainable and convoys delivering bottled water are vulnerable to Improvised Explosive Devices (IEDs). Currently, raw water from indigenous sources, which has chemical and microbiological contaminants, is treated with reverse osmosis (RO), but only used for hygiene, with bottled water used for drinking. Due to the economic costs and risks to life of providing bottled water, decision-makers need to evaluate technology alternatives to treat raw water to supply safe drinking water. In this study, …
Nitrogen And Phosphorus Biomass-Kinetic Model For Chlorella Vulgaris In A Biofuel Production Scheme, William M. Rowley
Nitrogen And Phosphorus Biomass-Kinetic Model For Chlorella Vulgaris In A Biofuel Production Scheme, William M. Rowley
Theses and Dissertations
Chlorella vulgaris was cultured in microbioreactors using Bold’s Basal medium at varying nitrogen and phosphorus concentrations to define nitrogen and phosphorus utilization standards. Nutrient concentration was varied between 137 mg/L to 7.33 mg/L NO3-N and between 55.2 mg/L to11.0 mg/L PO4-P in five test scenarios. All were grown under a constant photoperiod at 22±2 °C and a mixture of 4 to 10% carbon dioxide/air. Maximum yield and growth rate occurred with the highest initial nitrogen and phosphorus concentrations. A statistically significant difference in biomass was found among all test levels at the end of the eight day growth period. Applying …
Economic Feasibility Of Installing An Anaerobic Digester On A Department Of Defense Installation, Russell A. Strange
Economic Feasibility Of Installing An Anaerobic Digester On A Department Of Defense Installation, Russell A. Strange
Theses and Dissertations
Improving technology has made anaerobic digestion a viable method for disposing of organic waste and creating alternative energy. The purpose of this research was to examine the feasibility of installing an anaerobic digester on a Department of Defense installation, and measure its contribution to the execution of Executive Order 13423. A present worth equation was derived in accordance with 10 Code of Federal Regulations 436 expressing viable costs and benefits of an anaerobic digester. A case study of Wright Patterson Air Force Base (WPAFB) was then presented using the derived equation and operational data from functional digesters in the Ohio …
Modeling The Fate Of Groundwater Contaminants Resulting From Leakage Of Butanol-Blended Fuel, Khai H. Vuong
Modeling The Fate Of Groundwater Contaminants Resulting From Leakage Of Butanol-Blended Fuel, Khai H. Vuong
Theses and Dissertations
Fuel spills and leaks from storage tanks can contaminate groundwater. Typically in groundwater, hazardous aromatic hydrocarbons like benzene are attenuated through natural processes. However, it is possible that adding butanol to gasoline will interfere with these natural attenuation processes, so that spills and leaks of alternative fuels containing biobutanol may result in more persistent hazardous aromatic hydrocarbon plumes. This effect has already been observed with ethanol, which is currently added to gasoline. A numerical model was developed to simulate the subsurface fate and transport of butanol-blended fuel to assess the potential impacts of butanol on the natural attenuation of benzene. …