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Survivability Analysis Of The Iridium Low Earth Orbit Satellite Network, Douglas K. Stenger
Survivability Analysis Of The Iridium Low Earth Orbit Satellite Network, Douglas K. Stenger
Theses and Dissertations
This thesis evaluates the survivability of the proposed Iridium Low Earth Orbit (LEO) Satellite Network. In addition to the complete Iridium constellation, three degraded Iridium constellations are analyzed. This analysis occurs via the use of simulation models, which are developed to use three dynamic routing algorithms over three loading levels. The Iridium network models use a common set of operating assumptions and system environments. The constellation survivability was determined by comparing packet rejection rates, hop' counts, and average end to end delay performance between the various network scenarios. It was concluded that, based on the established scenarios, the proposed Iridium …
An Incremental Language Conversion Method To Convert C++ Into Ada95, Ding-Yuan Sheu
An Incremental Language Conversion Method To Convert C++ Into Ada95, Ding-Yuan Sheu
Theses and Dissertations
This thesis develops a methodology to incrementally convert a legacy object oriented C++ application into Ada95. Using the experience of converting a graphic application, called Remote Debriefing Tool (RDT), in the Graphics Lab of the Air Force Institute of Technology (AFIT), this effort defined a process to convert a C++ application into Ada95. The methodology consists of five phases: (1) reorganizing the software application, (2) breaking mutual dependencies, (3) creating package specifications to interface the existing C++ classes, (4) converting C++ code into Ada programs, and (5) embellishing. This methodology used the GNAT's C++ low level interface capabilities to support …
A Software Architecture For Computer Generated Forces In Complex Distributed Virtual Environments, Vincent B. Zurita
A Software Architecture For Computer Generated Forces In Complex Distributed Virtual Environments, Vincent B. Zurita
Theses and Dissertations
Complex Distributed Virtual Environments (DVEs) present an outstanding opportunity for the Department of Defense to train geographically separated units within a single realistic threat environment with minimal logistical considerations or safety concerns. To increase the fidelity of these simulations, minimize cost, and thereby maximize the training potential, DVEs must be populated with a realistic number of Computer Generated Forces (CGFs). These are currently expensive to design and build due to a lack of standard COF architectures. A solution to this problem is presented in the form of a CGF Architecture that is applicable to CGFs that model any weapon system. …
Speaker Recognition By Hidden Markov Models And Neural Networks, Erik J. Zeek
Speaker Recognition By Hidden Markov Models And Neural Networks, Erik J. Zeek
Theses and Dissertations
As humans, we develop the ability to identify people by their voice at an early age. Getting computers to perform the same task has proven to be an interesting problem. Speaker recognition involves two applications, speaker identification and speaker verification. Both applications are examined in this effort. Two methods are employed to perform speaker recognition. The first is an enhancement of hidden Markov models. Rather than alter some part of the model itself, a single-layer perceptron is added to perform neural post-processing. The second solution is the novel application of an enhanced Feature Space Trajectory Neural Network to speaker recognition. …
Collaborative Workspaces Within Distributed Virtual Environments, William D. Wells
Collaborative Workspaces Within Distributed Virtual Environments, William D. Wells
Theses and Dissertations
In warfare, be it a training simulation or actual combat, a commander's time is one of the most valuable and fleeting resources of a military unit. Thus, it is natural for a unit to have a plethora of personnel to analyze and filter information to the decision-maker. This dynamic exchange of ideas between analyst and commander is currently not available within the distributed interactive simulation (DIS) community. This lack of exchange limits the usefulness of the DIS experience to the commander and his troops. This thesis addresses the commander's isolation problem through the integration of a collaborative workspace within AFIT's …
Solar System Modeler: A Distributed, Virtual Environment For Space Visualization And Gps Navigation, Gary E. Williams
Solar System Modeler: A Distributed, Virtual Environment For Space Visualization And Gps Navigation, Gary E. Williams
Theses and Dissertations
The Solar System Modeler (SM) extends the Space Modeler developed in 1994. It provides a virtual environment enabling an explorer to dynamically investigate near Earth satellites, deep space probes, planets, moons, and other celestial phenomena. The explorer navigates the virtual environment via mouse selected options from menu panels while wearing a tracked, head mounted display (HMD). Alternatively, a monitor may replace the HMD and keyboard controls replace head tracking. The SM's functionality is extended by the ability to broadcast simulated GPS satellite transmissions in compliance with Distributed Interactive Simulation (DIS) protocol standards. The transmissions include information found in true GPS …
Neural Network Classification Of Environmental Samples, Jeffrey L. Blackmon
Neural Network Classification Of Environmental Samples, Jeffrey L. Blackmon
Theses and Dissertations
This research develops a general methodology for designing neural network classifiers for real-world environmental problems. This methodology is demonstrated through the design of a multi-layer perceptron to classify stainless steel and actinide samples. Neural networks, sometimes called artificial neural networks, have been shown capable of classifying complex patterns. Artificial neural networks are physiologically motivated computer algorithms which attempt to mimic the function of the large interconnected network of neurons in the human brain, which has extraordinary pattern recognition capabilities. These artificial neural networks learn to map a set of input features, elemental composition, onto a set of outputs such as …
An Investigation Of Instantaneous Plume Rise From Rocket Exhaust, Paul F. Sand
An Investigation Of Instantaneous Plume Rise From Rocket Exhaust, Paul F. Sand
Theses and Dissertations
Rocket launches at Vandenburg Air Force Base and Cape Canaveral Air Station produce exhaust clouds containing several toxic by-products, including HC1 and A12O3. These clouds rise to atmospheric stabilization heights, and then start dispersing and diffusing through the air. Upon reaching the ground, concentration levels of the toxins may present a human health risk. To predict these risks and concentration levels, range officials use a computer program titled the Rocket Effluent Exhaust Diffusion Model (REEDM). The version currently in use has been shown to underpredict the stabilization height of the exhaust cloud. This thesis examines the theory and algorithms used …
Applying Probabilistic Risk Assessment And Decision Analysis Techniques To Avoid Excessive Remedial Investigation Costs, Alejandro Hinojos
Applying Probabilistic Risk Assessment And Decision Analysis Techniques To Avoid Excessive Remedial Investigation Costs, Alejandro Hinojos
Theses and Dissertations
The majority of remediation resources have been consumed by costly and lengthy remedial investigation studies to characterize the human health risk. Unable to deal directly with the uncertainty resulting from the convolution of the uncertainties in a multitude of variables, and heavily persuaded by the liabilities, decision makers and regulators have relied on conservative assumptions and more studies to take appropriate actions. The main objective of this research is to provide tools and techniques to aid risk analysts in determining whether it would be beneficial to gather additional information or whether the decision to take an appropriate action can be …
Determining The Optimum Strategy Of Techniques From The Municipal Solid Waste Management Hierarchy To Maximize Social Value, Camille M. Still
Determining The Optimum Strategy Of Techniques From The Municipal Solid Waste Management Hierarchy To Maximize Social Value, Camille M. Still
Theses and Dissertations
Environmental managers must make difficult decisions regarding how to manage solid waste generation and disposal. The primary waste management alternatives are source reduction, recycling, composting, incineration, and landfilling often, waste management policies are based entirely on technical considerations and ignore that actual disposal practices depend on individuals' attitudes and behaviors. This research formulated a decision analysis model that incorporates social value measures to determine the waste management strategy that maximizes the individuals' willingness to participate. The social values that are important and that were considered in the decision support model to assist with making decisions about solid waste management were …
Development Of Synthetic Soils For Sorption Mass Transfer Model Validation, Thomas P. De Venoge
Development Of Synthetic Soils For Sorption Mass Transfer Model Validation, Thomas P. De Venoge
Theses and Dissertations
Existing sorption models often fail to describe grain scale sorption because of an inability to define the diffusion domain. A proposed improved model required testing to determine model validity. The testing method used a synthetic media of known geometry such that the distribution of sorption sites was known. Sorption rate data was obtained using batch experiments with the media. Data was used in comparison against model predicted rates. Fined sorption site distributions were compared to real distributions obtained by controlling sorbent geometries. Comparison determined model performance in fitting known distributions. The focus of this study was to (1) determine what …
Habitat Suitability Mapping Through Integration Of Multicriteria Evaluation Techniques With A Geographic Information System (Gis), Anthony A. Ference
Habitat Suitability Mapping Through Integration Of Multicriteria Evaluation Techniques With A Geographic Information System (Gis), Anthony A. Ference
Theses and Dissertations
The presence of an endangered species, the Pacific Pocket Mouse (PPM), in critical Marine Corps training areas aboard Camp Pendleton may adversely affect training activities that are crucial to meeting the Marine Corps' mission. Camp Pendleton must focus limited budgetary assets for live trapping surveys of the PPM in the areas of best habitat suitability and the purpose of this study was to develop a PPM habitat suitability map of Camp Pendleton. Suitability maps were developed by integrating expert opinion with the Camp Pendleton Geographic Information System (GIS) database.
Economic Valuation Of Air Force Environmental Resources: A Contingent Valuation Case Study, Timothy P. Haynie
Economic Valuation Of Air Force Environmental Resources: A Contingent Valuation Case Study, Timothy P. Haynie
Theses and Dissertations
The Air Force spends $1 billion each year to preserve, maintain, and restore environmental resources under its control (Budget of the United States Government, 1994). Assessing the benefit of this spending is a central issue in federal environmental management. As federal environmental management moves from a "clean it up at any cost" mentality to one which carefully considers the costs and benefits of spending, a fundamental question arises: What value of environmental resources does our environmental spending provide? As in any rational economic exchange benefits must exceed costs; the value of an environmental resource which benefits from public spending must …
A Decision Support Model For Municipal Solid Waste Recycling At United States Air Force Installations, Gergory A. Williams
A Decision Support Model For Municipal Solid Waste Recycling At United States Air Force Installations, Gergory A. Williams
Theses and Dissertations
The United States Air Force requires each installation to operate a municipal solid waste recycling program. Two inherently conflicting objectives, waste material diversion and financial result, have been established for the program. Reducing landfill disposal is the primary objective, but the incentive for profit is strong because each installation can retain profits from the program. Installations can be divided into two distinct areas, commercial and residential, based on the waste stream composition and funding. Structuring of the recycling program is often done in an ad-hoc manner. A decision support model was developed to evaluate four methods for each area. The …
Local Effects Of Solid Rocket Motor Exhaust On Stratospheric Ozone Concentrations, Brian K. George
Local Effects Of Solid Rocket Motor Exhaust On Stratospheric Ozone Concentrations, Brian K. George
Theses and Dissertations
Solid Rocket Motors (SRMs) power the initial flight of the Space Shuttle and Titan IV rocket. During those first two minutes after liftoff, the exhaust plumes from these motors emit large quantities of chlorine compounds and alumina particles into the atmosphere. For years scientists have argued that such a large chlorine input, injected directly into the stratosphere, would photochemically react with the surrounding air to cause significant ozone depletion. To answer the question of whether SRM exhaust causes a significant ozone depletion, Version 7 data from the Total Ozone Mapping Spectrometer (TOMS) instrument was analyzed for the 30 days prior …
Mass Transport Of Volatile Organic Compounds Between The Saturated And Vadose Zones, Monte S. Harner
Mass Transport Of Volatile Organic Compounds Between The Saturated And Vadose Zones, Monte S. Harner
Theses and Dissertations
Volatile organic compounds (VOCs) dissolved in the saturated zone are transported into the vadose zone primarily by gaseous phase diffusion. If the saturated zone is remediated, VOCs present in the vadose zone may become a secondary source of contamination for the groundwater. The amount of VOCs that remain in the vadose zone is dependent on site hydrology, soil properties, and the chemical properties of the contaminants. The purpose of this study was to determine what conditions caused VOC concentrations in the vadose zone to significantly recontaminate the saturated zone. A one-dimensional numerical model was developed to investigate the transport of …
Independent Verification And Validation Of The Hazardous Material Cost Trade-Off Analysis Tool Developed By The Human Systems Center At Brooks Air Force Base, Thomas S. Choi
Theses and Dissertations
The Air Force realizes that the life cycle cost (LCC) associated with hazardous materials is a significant cost in the acquisition of major weapon systems. In trying to mitigate the growth of environmental LCC for future weapon systems, the Air Force has developed a tool called the Hazardous Material Cost Trade-off Analysis Tool (HAZMAT CTAT). The HAZMAT CTAT estimates the LCC for weapon system hazardous materials, so that intelligent decisions can be made in the early stages of the acquisition process. The problem with implementing this program into the acquisition process is that an independent computer model evaluation has never …
Study Of Desorption Of Contaminant From Synthetic Soil, Kung-Fu Hwang
Study Of Desorption Of Contaminant From Synthetic Soil, Kung-Fu Hwang
Theses and Dissertations
A better understanding of sorption and desorption processes could improve estimates of time and cost required for remedial activities, exposure times and health risk, and bioavailability. Conventional rate-limited sorption models do not accurately define the diffusion domain at the grain scale. Heyse (1994) proposed the multiple sites in series (MSS) model, which allows more general description of the geometry of the sorption domain than the classical spherical or discrete distributions. A version of this model was tested by deVenoge (1996). The model was able to accurately simulate sorption rate data, but could not estimate unique geometry parameters. This research is …
Evaluating The Hazardous Materials (Hazmat) Pharmacy Among Air Force Majcoms Using Waste Reductions And Activity Indicators, W. Edward Iseman Jr.
Evaluating The Hazardous Materials (Hazmat) Pharmacy Among Air Force Majcoms Using Waste Reductions And Activity Indicators, W. Edward Iseman Jr.
Theses and Dissertations
The Hazardous Materials (HazMat) Pharmacy has been designed as an environmentally friendly vehicle to handle, store, dispense, track, recycle, and dispose of hazardous materials in the Air Force. This thesis effort proposed a method in which valuable feedback for the pharmacy can be obtained. Because it is still in the early stages of implementation, there has been little feedback on the pharmacy. An activity index that uses a variable most closely associated with the generation of hazardous waste in a MAJCOM is proposed. Using an aircraft maintenance related variable, like maximum take-off weight, the fluctuations in mission over time can …
A Comparative Analysis Of Two Alternatives To Chemical Aircraft Paint Stripping, George P. Joyce Ii
A Comparative Analysis Of Two Alternatives To Chemical Aircraft Paint Stripping, George P. Joyce Ii
Theses and Dissertations
The Air Force must periodically strip and paint its aircraft to prevent the damaging effects of corrosion. The paint removal process typically involves the use of toxic chemicals such as methylene chloride which are soon to be banned as a result of impending environmental regulations and increased costs associated with handling and disposing of such material. The Air Force must choose an alternative to methylene chloride chemical stripping which complies with environmental regulations and reduces costs. This thesis compares the life cycle costs and environmental impacts of two alternatives to chemical aircraft stripping. Plastic Media Blasting (PMB) and Modified Medium …
Analysis Of Air Force Environmental Justice Methodology, Barbara E. Owens
Analysis Of Air Force Environmental Justice Methodology, Barbara E. Owens
Theses and Dissertations
The purpose of this study is to analyze AFCEE's draft environmental justice methodology. The study provides background on the meaning of environmental justice along with related terminology, and covers historical events of the environmental justice movement leading up to the publication of EO 12898. A discussion of EO 12898, subsequent draft guidance, and other pertinent literature leads to the development of evaluation criteria used to analyze both AFCEE's methodology and an application of that methodology: the March AFB Disposal Final Environmental Impact Statement Given that AFCEE formed their own methodology to address environmental justice prior to any definitive guidance regarding …
Modeling Plant Uptake Of Metal In Constructed Wetlands Supported By Experimentally Derived Uptake Rates, Michael B. Peake
Modeling Plant Uptake Of Metal In Constructed Wetlands Supported By Experimentally Derived Uptake Rates, Michael B. Peake
Theses and Dissertations
Many communities and Air Force installations are using constructed wetlands to filter trace metals from their stormwater runoff. Constructed wetlands are attractive to industry for runoff mitigation because they are relatively cheap to build and operate and require little or no energy for operation. The purpose of this research project is to develop quantitative concepts for understanding the dynamics of metal uptake in constructed wetland plants by constructing a system dynamics model supported by experimental observation and offer environmental managers a tool to simulate, under a broad range of conditions, long term wetland exposure to stormwater runoff contaminated with trace …
Investigation Of Sorption Mass Transfer Models Using Synthetic Soils, Karla K. Mika
Investigation Of Sorption Mass Transfer Models Using Synthetic Soils, Karla K. Mika
Theses and Dissertations
Grain-scale sorption mass transfer is an important process that must be considered when predicting clean-up time and choosing remediation techniques for subsurface hazardous waste contamination. Rate-limited sorption is responsible for the rebound effect, where remediated groundwater is recontaminated by desorption. Sorbed contaminants are not available for microbial degradation, and the desorption rate may govern the effectiveness of natural attenuation by biodegradation. Grain-scale sorption nonequilibrium is generally attributed to diffusive transport, either in SOM or in mineral micropores. Typically used sorption mass transfer models either fail to reproduce long-term slow desorption (first-order models), or are based on diffusion in assumed (often …
An Activity Driver Based Analysis Of Hazardous Materials Usage At Wright-Patterson Afb, Charles D. Perham
An Activity Driver Based Analysis Of Hazardous Materials Usage At Wright-Patterson Afb, Charles D. Perham
Theses and Dissertations
As the Air Force has progressed and succeeded in the realm of pollution prevention, the opportunities for further progress have become more challenging. With the 'low-hanging fruit' now gone from the pollution prevention tree, new methods to identify opportunities must be adopted. This research effort applied a subset of activity based costing, activity driver analysis, to reveal pollution prevention opportunities in regards to hazardous materials usage. A sample of base organizations (civil engineering and aircraft maintenance), and a sample of the hazardous chemicals (Class C or most hazardous) used by those organizations were investigated to determine the drivers behind usage.
Environmental Attitudes And Behaviors: An Examination Of The Antecedents Of Behavior Among Air Force Members At Work, Mark S. Laudenslager
Environmental Attitudes And Behaviors: An Examination Of The Antecedents Of Behavior Among Air Force Members At Work, Mark S. Laudenslager
Theses and Dissertations
A questionnaire was randomly distributed to members of the United States Air Force at Wright Patterson AFB, OH, with 307 returned. The survey was designed to test the theory of planned behavior (TPB) model developed by Icek Ajzen, and the organizational theory of planned behavior (OTPB) model explored in this research effort. Validation and measurement of the TPB in relation to an organizational setting was accomplished, with the organizational theory of planned behavior (OTPB) developed. The behaviors and intentions individuals have towards recycling, energy conservation, and carpooling were examined, with the demographic variables of gender, age, and education also investigated. …
Environmental Restoration Project, Peer Review Process Assessment, Paul A. Schantz
Environmental Restoration Project, Peer Review Process Assessment, Paul A. Schantz
Theses and Dissertations
Installation Restoration Program (IRP) projects often cost over $250 thousand, and projects over $1.5 million are common. To ensure these projects are risk based, technically sound, and cost effective, the Air Force instituted a peer review program in 1992. The objective of this research is to describe and analyze the peer review process. Through triangulation of data from interviews, observations, official and academic documents, and surveys, seven constructs were discovered: focus, agenda, facilitator, written preparation, oral presentation, team characteristics, and reviewer characteristics. A questionnaire was used to gather perceptions of peer review effectiveness--the criterion variable--and of the seven constructs. A …
Surfactant Enhanced Microbial Degradation Of Jp-8 Contaminated Soil, John D. Thomas
Surfactant Enhanced Microbial Degradation Of Jp-8 Contaminated Soil, John D. Thomas
Theses and Dissertations
This research effort used an automated respirometer to evaluate the enhancement of JP-8 fuel biodegradation, from surfactant addition. Two nonionic surfactants, Novell 1412-7 and Alfonic 810-4.5 were chosen for addition to contaminated JP-8, microcosms at three levels of treatment. The three levels of treatment included sub-CMC, CMC, and supra-CMC concentrations for each surfactant. The Novell II, nonionic surfactant, exhibited inhibitory characteristics, and was eliminated from the study. The focus of the study was to determine if JP-8 was actually degraded, and if enhancement of JP-8 biodegradation would be achieved from surfactant addition. The respirometer was found to be repeatable within …
Modeling Marine Exposure To Polychlorinated Biphenyls From Sunken Ships, Charles N. Wendt
Modeling Marine Exposure To Polychlorinated Biphenyls From Sunken Ships, Charles N. Wendt
Theses and Dissertations
In the past, the U.S. Navy has routinely conducted SINKing EXercises (SINKEX) for training, weapon effectiveness tests, and economic disposal of aging assets. Recent concern over polychlorinated biphenyl (PCB) chemicals aboard such target vessels has resulted in a suspension of SINKEX. The U.S. Navy has approximately 200 vessels currently requiring such disposal. Environmental legislation and health concerns preclude selling such vessels to foreign governments or scrapping. This work attempted to model the fate and transport of these PCBs by examining their transport to coastal water and their accumulation in the marine food chain. The model includes biodegradation, upwelling, partitioning of …
Evaluation Of Hazardous Material Life Cycle Cost Tools For Use In Air Force Hazardous Material Pharmacies, Rowene J. Resler
Evaluation Of Hazardous Material Life Cycle Cost Tools For Use In Air Force Hazardous Material Pharmacies, Rowene J. Resler
Theses and Dissertations
This research focuses on evaluation of various tools that assist in the selection of hazardous material substitutes. Substitute material consideration is a function of the Hazardous Material Pharmacy (HMP) when a hazardous material is requested for purchase and use in a current base operation. The substitute material decision is complex, involving identification of potential substitutes and then comparison of factors, such as cost, performance, and environmental effects, between the potential substitute and the material being requested. Various tools such as life cycle cost models, databases, and other information services can provide assistance to HMPs making substitution decisions.
Development Of A Basis For A Hazardous Materials And Waste Management System For Air Force Contingency Deployments, Christopher J. West
Development Of A Basis For A Hazardous Materials And Waste Management System For Air Force Contingency Deployments, Christopher J. West
Theses and Dissertations
Increased awareness of the potential for adverse mission impact on deployments, recent experience on such deployments, and Air Force and Major Command interest establish the need for an integrated hazardous materials and waste management system for contingency environments. This research was focused toward establishing a basis for developing such a system. An intensive literature review was accomplished to justify the necessity of the research, characterize the contingency environment, review legal and regulatory requirements, review proper hazardous substance handling and processing procedures, and review existing and new material resources which may be employed in such a system. Further literature review led …