Digital Commons Network^™

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 …

Performance Analysis Of A Hartman Wavefront Sensor Used For Sensing Atmospheric Turbulence Statistics, Toby D. Reeves

Theses and Dissertations

Atmospheric turbulence parameters, such as Fried's coherence diameter, the outer scale of turbulence, and the turbulence power law, are related to the wavefront slope structure function (SSF). The SSF is defined as the second moment of the wavefront slope difference as a function of both time and position. Knowledge of the SSF allows turbulence parameters to be estimated. Hartmann wavefront sensor (H-WFS) slope measurements composed of both signal and noise, allow the SSF to be estimated by computing a mean square difference of H-WFS slope measurements. The quality of the SSF estimate is quantified by the signal-to-noise ratio (SNR) of …

High-Pressure Oxidation Rates For Large Coal And Char Particles, James A. Mathias

Theses and Dissertations

The main objective of this study was to investigate the factors that influence the oxidation rate of large (five to eight millimeters in diameter) coal and char particles. To accomplish this, experiments were performed in which the gas temperature, gas velocity, particle size, partial pressure of oxygen, and total pressure were varied. The experiments were performed with the cantilever balance attachment and the high pressure controlled profile reactor.

Approximately 90 combustion experiments were performed with Pittsburgh, Utah Blind Canyon, and Wyodak-Anderson coal. These experiments were performed at atmospheric pressure with air and varied gas temperature, gas velocity, and particle size. …

Converting Publications In The Air Force To Sgml: A Recommendation Based On Commercial Experience, Shari T. Miles

Theses and Dissertations

The objective of this research was to determine those benefits of SGML that the Air Force can use in its publications process and to determine if benchmarking can improve the Air Force's migration to an electronic publishing environment. To accomplish this, the author completed an exploratory, qualitative study which defined the components and benefits of SGML and the benchmarking application and process. The qualitative techniques for this research included a literature review and questionnaire. The literature review covered both SGML and benchmarking. The questionnaire was an exploratory instrument that was sent to 60 commercial enterprises. The results of the questionnaire …

Automated Document Conversion: A Manager's Perspective, Fredrick W. Knaak Iii

Theses and Dissertations

Technological advances in our workplaces have made electronic documents pervasive throughout the USAF, DoD, and civilian world. Managers are recognizing the need to establish electronic document management systems to handle these diverse forms of documents. Unfortunately, they have been faced with essentially "reinventing the wheel," when it comes to determining which types of paper-based documents are best suited to conversion to an electronic format. There is also a lack of clearly identifiable cost factors associated with automated document conversion (ADC) for managers to use when conducting an economic analysis of a potential imaging application. This thesis addresses the problem of …

Influence Of Tip Clearance On The Flowfield In A Compressor Cascade With A Moving Endwall, Richard J. Mcmullan

Theses and Dissertations

The effects of changing the blade tip clearances on the velocity and pressure flowfields within a compressor cascade were investigated in this experimental thesis. All moving endwall measurements were taken at a constant flow coefficient of 0.5 and tip clearances of 0.5, 1.0 and 2.0 percent chord. Hot-wire/film probes were used to determine the three-dimensional velocity vector components in various transverse planes - one upstream of the leading edges of the blades, three within the blade cascade and one downstream of the trailing edges of the blades. The transverse velocity vector plots showed a scraping of the tip leakage vortex …

Model Predictive Control Of Aerospace Systems, Derek W. Ebdon

Theses and Dissertations

The primary objective of this thesis is to explore the fault tolerance capabilities of a state space formulation of MPC. Subsequent to a simulated control surface failure on the F-18 High Alpha Research Vehicle (HARV), the MPC controller will attempt to maintain stability and nominal performance while tracking a setpoint. Secondary objectives include studying the effect of data sample rate and MPC horizon lengths on system performance. These objectives will be accomplished using Matlab to develop the MPC controller and Simulink to demonstrate its effectiveness through simulation.

Artificial Cochlea Design Using Micro-Electro-Mechanical Systems, George C. Dalton Ii

Theses and Dissertations

The use of Micro-Electro-Mechanical Systems (MEMS) in the design of an artificial cochlea is investigated in depth. Interdigitated finger (comb), cantilever, bridge, and mirror resonators are presented as possible devices used to implement the artificial cochlea. These resonators are demonstrated to be extremely high Q devices, capable of being tuned with a simple DC bias. This suggests a possible change to existing cochlea models that claim highly complex AC feedback as being responsible for changes in the damping of the basilar membrane. The new cochlea model presented here, using MEMS to approximate the tuning of the basilar membrane, may be …

Elicitation Of Formal Software Specifications From An Object-Oriented Domain Model, Timothy Karagias

Theses and Dissertations

The ability to provide automated support for the generation of formal software specifications would lead to decreased software development time. By eliciting the needed information from a software developer and harvesting the proper parts of a domain model, a software specifications document could be created. This research establishes the feasibility of producing customized software specifications based on an object-oriented domain model. The research was conducted in three phases. The first phase was to define the requirements for the Elicitor Harvester. Those requirements were balanced between the capabilities of the existing Knowledge Based Software Engineering (KBSE) software used at AFIT and …

A Test-Case Based Approach To Bayesian Knowledge Base Incompleteness Detection And Correction, Louise J. Lyle

Theses and Dissertations

This work develops tools and techniques to identify particular Bayesian Knowledge Base (BKB) incompletenesses, and to modify the existing knowledge-base (KB) structure to correct these problems. The methodology performs manually or automatically, informing the user of either problems causing the incompleteness, or of details resulting from the automatic knowledge-base correction. The proposed methodology is designed for integration with BVAL, to augment BVAL's validation techniques.

The Development Of A Scenario Translator For Distributed Simulations, Heon-Gyu Park

Theses and Dissertations

There exists a variety of simulation generation and analysis products which have differing purposes and functions designed to simulate a real military battlefield. Due to the particular purpose of each simulation it is impractical to use one scenario of a simulation directly with another simulation without a translator since there is no standard scenario format. In the current environment interoperability between simulations is becoming more important in large scale simulations and distributed exercises. The Scenario File Translator (SFT) provides an easy and accurate way to create a scenario from a heterogeneous simulation. The SFT can load and save the three …

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

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

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.

The Biodegradation Characteristics Of Proposed Fuel Systems Icing Inhibitors (Fsii), Charles E. Meshako

Theses and Dissertations

The biodegradation characteristics of three fuel system icing ihhibitors (FSII) were evaluated. FSII are jet fuel additives that partition into water readily and are present in the water drained from storage tank bottoms in concentrations approaching 40%. These concentrations raise concerns as to the disposal and handling of these wastes. The current FSII, DiEGME was evaluated along with two new candidates, dipropylene glycol and glycerol formal. DiEGME appeared to be moderately but not completely biodegradable. It is likely that much of it would be removed in a wastewater treatment plant. Dipropylene glycol only showed signs of degradation after more than …

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. …

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 …

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.

Investigation Of Ba, Bao, Sr And Sro Pulsed Laser-Induced Vapor Plumes In N2, O2, Microwave Discharged O2, And Vacuum At Low Laser Fluence, David L. Byers

Theses and Dissertations

Ba, BaO, Sr and SrO were ablated by 248 nm laser pulses at fluences ranging from 270 mJ-/cm² to 575 mJ-/cm² in vacuum and in 25 mtorr atmospheres of N2, O2 and microwave-discharged O₂. The spectral emissions of these plumes were compared for indications of ionization due to Ba or Sr collisions with each gas. The addition of a background gas increased the ion and neutral signature across the spectrum. SrO band emission was observed at 16,600-16,900/cm and possible BaO band emissions were observed in the 18,250-18,400/cm, 19,000-19700/cm and 19,800-20,000/cm regions. A screened plate ion probe …

Personnel Airdrop Risk Assessment Using Bootstrap Sampling, Wonsik Kim

Theses and Dissertations

Previous work on personnel airdrop problems involving jumpers has been (1) event-oriented entanglement rates, (2) number of canopy bumps, (3) landing injuries, and (4) deaths. The thesis expands this area of research by developing cumulative distribution functions of maximum possible chute entanglement risk for the C-17 using bootstrap techniques. By comparing the effects of various C-17 aircraft configurations on the entanglement CDF, this thesis shows that under certain configurations the risk of centerline entanglement for the C-17 is less than for the C-141.

Deconvolution From Wavefront Sensing Using Optimal Wavefront Estimators, Scott R. Maethner

Theses and Dissertations

A cost effective method to improve the space surveillance mission performance of United States Air Force (USAF) ground-based telescopes is investigated and improved. A minimum variance wavefront estimation technique is used to improve Deconvolution from Wavefront Sensing (DWFS), a method to mitigate the effects of atmospheric turbulence on imaging systems that does not require expensive adaptive optics. Both least-squares and minimum variance wavefront phase estimation techniques are investigated, using both Gaussian and Zernike polynomial elementary functions. Imaging simulations and established performance metrics are used to evaluate these wavefront estimation techniques for a one-meter optical telescope. Performance metrics include the average …

Estimation Of Satellite Orientation From Space Surveillance Imagery Measured With An Adaptive Optics Telescope, Gregory E. Wood

Theses and Dissertations

The use of the matched filter to automatically estimate the pose of a Low Earth Orbiting satellite from imagery taken with an adaptive optics telescope is explored. This work represents the first effort to solve the satellite pose estimation problem while considering the broad range of atmospheric turbulence levels and target visual magnitudes that are encountered in ground based space surveillance operations. Several Algorithms are examined in an effort to determine the performance bounds on the matched filter for this application. Results are given over an extremely wide range of seeing conditions. These results are weighted based on historical data …

The Capacity Of The Air Force Satellite Control Network, Kwangho Jang

Theses and Dissertations

The daily mission objective of the Air Force Satellite Control Network (AFSCN) is to support communication with satellite systems. It is critical that the AFSCN operate 24 hours a day, seven days a week. Previous work on the satellite range scheduling problem has successfully scheduled over 90 percent of the satellite support requests. This research investigates the capacity of the AFSCN using an available satellite scheduling algorithm. This research has three objectives. The first objective is to be able to generate sample data sets which represent a day of satellite support requests for low, medium, and high altitude satellites. The …

The New Logic Of Hypertext: Electronic Documents, Literary Theory, And Air Force Publications, Gordon G. Geison

Theses and Dissertations

Hypertext systems offer electronic links that can instantly join related documents with the click of a mouse. Some observers predict that in the next few years hypertext will become the predominate technology of communication. Such a revolutionary transformation of our culture's basic system for sharing information is bound to have a profound and wide-ranging impact. At this early stage in hypertext's evolutionary development, no empirical study can be expected to capture the long-term implications of this new technology. An exploratory survey was distributed to 100 large corporations to gather their initial assessment of the revolutionary implications of hypertext. The results …

Manipulating The Ooda Loop: The Overlooked Role Of Information Resource Management In Information Warfare, Gregory M. Schechtman

Theses and Dissertations

A ground-swell of interest in information as a weapon of warfare is growing within the U.S. armed services. Military strategists are looking at information as a tool to leverage our forces and make them irresistible in battle. Yet, there is little agreement as to what information warfare (IW) is, let alone how it is best fought. This fundamental disagreement is serving as an impediment to unified actions as the Air Force seeks its role in this arena. In particular, information resource management practitioners are questioning their role in supporting this mission. This thesis discusses limitations of existing information warfare interpretations …

On-Line Publications: Defining Requirements For User Acceptance, Jefferey T. Hennes

Theses and Dissertations

This study investigated user requirements for an on-line system to distribute United States Air Force publications. Requirements were gathered utilizing focus groups of users from the students and staff of the Air Force Institute of Technology. The focus groups identified requirements for the system intended to foster its acceptance within the user community. The conceptual framework posited user involvement in the design and implementation of the new system, providing a balance between functionality and ease of use fostering user acceptance. The framework was used to examine the relationships between the user’s involvement in the system design and implementation and its …

Air Force Media Use And Conformance With Media Richness Theory: Implications For E-Mail Use And Policy, Heather L. Adams

Theses and Dissertations

Communication has become a major aspect of a manager's job. When communicating, they are faced with many choices of what media to use - some include face-to-face, telephone, e-mail, or written. Managerial effectiveness can improve if managers make appropriate media choices. Thus, it is important to study how Air Force managers perceive media and what kind of choices they are making based on those perceptions. Media Richness Theory suggests that media choices are affected by content reasons, situational reasons, and symbolic reasons. This study examined Air Force managers and found they conform highly with Media Richness Theory in their media …

Records Analysis And Classification System: A Proof Of Concept System For The Automated Classification Of United States Air Force Records, David W. Snoddy

Theses and Dissertations

The records management process utilized within the Department of Defense (DoD) is currently labor intensive. Work is being done to automate portions of this process, but classifying documents and assigning disposition instructions remains a labor intensive, manual operation. Although the requirement for this capability was identified by a DoD sponsored study, an automated computer-based system which can classify and apply disposition instructions has yet to be developed for use within the DoD. This thesis study presents a proof of concept computer program called the Records Analysis and Classification System (RACS) which was developed to demonstrate computer-based techniques for the automated …

Whose Information Is It Anyway? An Argument For Information Stewardship, Trevor W. Plant

Theses and Dissertations

Information is an important resource for businesses and government, with information quality influencing decision quality, and highlighting our need to manage our information well: as a resource. Information Resource Management (IRM) has as its goal the management of information as a resource, but has not been implemented with the level of success expected. Problems with the implementation of IRM are indicated by the presence of redundant or inconsistent data, inability to share information across systems, and difficulty finding the information on systems. We propose that these difficulties are related to behaviours linked to perceived ownership of corporate information by organisational …

Internet Use Patterns, Acceptance Levels, And Policy Recommendations: An Information Technology Infusion Approach To The Internet And The United States Air Force, Pamela E. Quintero

Theses and Dissertations

Information technology infusion has taken place in the workplace as costs for microcomputers have declined and the need for reliable and timely information has increased, but the impact the Internet has had is yet to be determined. This research takes an information technology infusion approach to the Internet and focuses on the use patterns of current Air Force Internet users, acceptance levels, and supervisory support of the technology, as well as policy recommendations regarding Internet use in the Air Force. The research provides substantial evidence that Internet technology is not being infused equally within all organizational levels in the Air …