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Computer-Based Methods For Constructing Two-Level Fractional-Factorial Experimental Designs With A Requirement Set, Steven L. Forsythe Dec 2000

Computer-Based Methods For Constructing Two-Level Fractional-Factorial Experimental Designs With A Requirement Set, Steven L. Forsythe

Theses and Dissertations

This dissertation developed four methodologies for computer-aided experimental design of two-level fractional factorial designs with requirement sets (DOE/RS). The requirement sets identify all the experimental factors and the appropriate interaction terms to be evaluated in the experiment. Taguchi graphs and similar manual methods provide techniques for solving the DOE/RS problem. Unfortunately, these methods are limited because they become difficult to use as the number of factors or interaction terms exceeds ten. This research showed that the DOE/RS problem belongs to a class of difficult-to-solve problems known as NP-Complete. It is the combinatorial nature of NP-Complete problems that causes them to …


Validation And Verification Of Formal Specifications In Object-Oriented Software Engineering, Steven A. Thomson Sep 2000

Validation And Verification Of Formal Specifications In Object-Oriented Software Engineering, Steven A. Thomson

Theses and Dissertations

The use of formal specifications allows for a software system to be defined with stringent mathematical semantics and syntax via such tools as propositional calculus and set theory. There are many perceived benefits garnered from formal specifications, such as a thorough and in-depth understanding of the domain and system being specified and a reduction in user requirement ambiguity. Probably the greatest benefit of formal specifications, and that which is least capitalized upon, is that mathematical proof procedures can be used to test and prove internal consistency and syntactic correctness in an effort to ensure comprehensive validation and verification (V&V). The …


Algorithm Development For On-Line Control Of The Airborne Laser, Michael W. Oppenheimer Sep 2000

Algorithm Development For On-Line Control Of The Airborne Laser, Michael W. Oppenheimer

Theses and Dissertations

The use of adaptive optics entails the design of a controller. This requires the development of a model of the plant to be controlled, which, in this case, Consists of the atmosphere through which light is traveling. In optics, Zemike polynornials are used as a basis set for the expansion of wavefront phase distortions. Due to the turbulence induced stochastic nature of the underlying process involved, the spatial-temporal correlation functions of the Zemike polynomial phase expansion coefficients must be evaluated if a proper stochastic model of the plant is to be developed and adaptive optics is to be employed. In …


An Improved Algorithm For Translating Relational Schemas Into An Object Model, Joseph C. Pearson Jun 2000

An Improved Algorithm For Translating Relational Schemas Into An Object Model, Joseph C. Pearson

Theses and Dissertations

Today's war fighter is inundated with data from numerous Command, Control, Communications and Computers and Intelligence systems. Integration of these systems is desirable, yet integration results in a static solution to a dynamic problem-by the time a global schema can be devised, it is out of date. Automating schema integration will mitigate this problem, but data model disparity must be addressed via translation to a common data model prior to integration. To address this requirement, this thesis presents an improved, relational to object-oriented schema translation algorithm, which is derived from a base algorithm proposed by another research effort. The improved …


A Comparative Analysis Of Proposed Mobility Support Schemes For Ip Multicast, Alexander Muller Jr. Apr 2000

A Comparative Analysis Of Proposed Mobility Support Schemes For Ip Multicast, Alexander Muller Jr.

Theses and Dissertations

This thesis introduces a novel mobile multicast transmission mechanism called Minimal Multicast Encapsulation. Additionally, this thesis analyzes the performance of mobility support schemes for IP multicast. Specifically, it compares the performance of combinations of two receive mechanisms and two transmit mechanisms. The receive mechanisms are the Internet Engineering Task Force (IETF) bi-directional tunneling mechanism and the IETF remote subscription mechanism. The transmit mechanisms are the IETF home tunneling mechanism and the Minimal Multicast Encapsulation. The performance analysis consists of examining path efficiencies, packet loss rates, and required mobility agent throughputs for each of the four possible combinations of the aforementioned …


An Analysis Of The Effectiveness Of A Constructive Induction-Based Virus Detection Prototype, Kevin T. Damp Apr 2000

An Analysis Of The Effectiveness Of A Constructive Induction-Based Virus Detection Prototype, Kevin T. Damp

Theses and Dissertations

Computer viruses remain a tangible threat to systems both within the Department of Defense and throughout the greater international data communications infrastructure on which the DoD increasingly depends. This threat is exacerbated continually, as new viruses are introduced at an alarming rate by the growing collection of connected machines and their operators. Unfortunately, current antivirus solutions are ill-equipped to address these issues in the long term. This thesis documents an investigation into the use of constructive induction, a form of machine learning, as a supplemental antivirus technique theoretically capable of detecting previously unknown viruses through generalized decision-making techniques. A group …


Validation Of The Ionospheric Forecast Model (Ifm) Version 3, Michael D. Scott Mar 2000

Validation Of The Ionospheric Forecast Model (Ifm) Version 3, Michael D. Scott

Theses and Dissertations

The purpose of this research was to validate the Ionospheric Forecast Model (IFM) Version 3 to assess its suitability and usefulness as an operational tool. The Ionospheric forecast model is a first principles computer model designed to forecast the state of the global ionosphere to 24 hours. The scope was limited to a comparison of the F2 layer critical frequency (foF2) and peak electron density (hmF2) against observed ionosonde data. The model was run with global solar and geomagnetic indices and Information from Digitial Ionospheric Sounding System (DISS) observations as inputs. The DISS observations were input through the Parameterized Real-Time …


An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll Mar 2000

An Analysis In Cloud-To-Ground Lightning Over Land Versus Water, Elizabeth A. Boll

Theses and Dissertations

Understanding lightning characteristics over land and water is vital to achieving optimal safety and success in Air Force missions. Lightning safety rules are often based on experience rather than a scientific understanding of lightning. Examining lightning characteristics over water and land will assist in a better understanding of lightning and provide answers that can protect human lives and property. Water and land have different compositions and surface conductivity values. A lightning stroke is detected through a change in the electro-magnetic field at the surface. The change in surface conductivity values from land to water can affect the detection of a …


Temperature Determination In An I2 Gas Using Dopper-Limited Saturation Spectroscopy, James W. Myers Jr. Mar 2000

Temperature Determination In An I2 Gas Using Dopper-Limited Saturation Spectroscopy, James W. Myers Jr.

Theses and Dissertations

Saturation spectroscopy techniques were used to demonstrate the ability to make spatially resolved temperature measurements by exploiting the B3 ∏(O+u) - X1 Σ ;(O+g) electronic transition in molecular iodine (I2). Doppler-free saturation spectroscopy measurements resulted in hyperfine spectral profiles for the P(7O) 17-1 and P(53) 19-2 ro-vibrational transitions between the electronic levels. Doppler-limited saturation spectroscopy, an adaptation of the Doppler-free technique in which beams propagate in the same direction and cross within the gas sample, allowed for the measurement of spatially resolved Doppler profiles for the same transitions. The profiles were measured …


Sensitivity Studies On A Limited Area Mesoscale Model: An Examination Of Lateral Boundary Placement, Grid Resolution And Nesting Type, Robert A. Stenger Mar 2000

Sensitivity Studies On A Limited Area Mesoscale Model: An Examination Of Lateral Boundary Placement, Grid Resolution And Nesting Type, Robert A. Stenger

Theses and Dissertations

With the advances of computer technology in recent years, limited area mesoscale models are being used to produce operational forecasts on a broader scale worldwide than ever before. The past limitations of computational resources have caused previous research efforts to focus more on model physics, thus creating a gap in the number of sensitivity studies conducted on these models. This research is intended to bridge a gap in the apparent paucity of sensitivity studies on the limited area model (LAM). The Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model 5 was utilized to conduct sensitivity studies on lateral boundary …


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

Quantifying The Protonospheric Effect On Prism, Kelly B. Doser

Theses and Dissertations

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


Tunable Mid-Ir Optical Parametric Oscillator Using Periodically Poled Rubidum Titanyl Arsenate, Frank J. Glavic Mar 2000

Tunable Mid-Ir Optical Parametric Oscillator Using Periodically Poled Rubidum Titanyl Arsenate, Frank J. Glavic

Theses and Dissertations

Tunable sources of coherent radiation are needed for a variety of military and commercial applications, including infrared countermeasures and atmospheric remote sensing. This research investigates a tunable mid-infrared coherent source using periodically-poled rubidium titanyl arsenate (PPRTA) as a quasi-phase matched (QPM) optical parametric oscillator (OPO). The advantages of PPRTA over periodically poled lithium niobate (PPLN) are presented. Quasi-phase matching and periodic poling theory are discussed, along with some important historical results and current developments. Experimental setups for determining threshold, conversion efficiency, pump depletion, and beam quality are presented along with experimental results. The research effort is focused on characterizing PPRTA …


Three-Dimensional Data Visualization Of Electronic Military Intelligence Using The Project Broadsword System, Michael L. Goeringer Mar 2000

Three-Dimensional Data Visualization Of Electronic Military Intelligence Using The Project Broadsword System, Michael L. Goeringer

Theses and Dissertations

Today's military electronic infrastructure solves many problems while creating others. Using computers, battlefield and global awareness is brought to bear through the near real-time linking of sensor platforms from around the globe. These intelligence networks produce vast amounts of data that must be parsed, interpreted, digested and stored by information gathering systems. As the amount of intelligence data continues to increase, these text-based systems become cumbersome and inadequate. To ensure vital information is not overlooked or discovered too late, other forms of intelligence product management and data navigation need to be investigated. This thesis explores procedures for enhancing the capabilities …


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

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

Theses and Dissertations

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


Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar Mar 2000

Modeling Chlorinated Ethene Removal In Constructed Wetlands: A System Dynamics Approach, Colby D. Hoefar

Theses and Dissertations

The purpose of this study is to gain understanding of the dynamics of the processes that degrade Perchloroethene (PCE) to ethylene, or carbon dioxide (CO2), within the confines of a constructed wetland. A system dynamics approach will be used. This model is focused on identifying and optimizing the naturally occurring processes in stratified wetland sediment that reduce mass, toxicity, mobility, volume or concentration of contaminants in groundwater. Contaminant fate and transport within a wetland system is extremely complex and the mechanisms that drive wetland behavior are dynamic. Confidence in the model was built through verification and testing. Reasonable …


Active Multispectral Bidirectional Reflectance Distribution Function Measurement System, Mark J. Proctor Mar 2000

Active Multispectral Bidirectional Reflectance Distribution Function Measurement System, Mark J. Proctor

Theses and Dissertations

Today's highly technical battlefield environment dictates the need for a method of standoff target identification, which reduces risk to personnel and equipment. It is widely known that a given material will react differently to incident radiation than a dissimilar material. Certain materials may respond specularly while others tend to be diffuse. By measuring these responses, materials can be identified by comparison with a known database. One method of building such a database for target recognition is by employing an active multi spectral bidirectional reflectance distribution function (BRDF) measurement system. In the following text, such a system is developed and tested …


Timing Of Thunderstorm Occurrence For Cape Canaveral, Florida, Thomas G. Renwick Mar 2000

Timing Of Thunderstorm Occurrence For Cape Canaveral, Florida, Thomas G. Renwick

Theses and Dissertations

This research is concerned with improving an existing algorithm to accurately forecast thunderstorm starting times for Cape Canaveral, Florida. This was accomplished by investigating different linear regression techniques than those used in the existing algorithm. The result is three new thunderstorm start time algorithms. The forecast start times of these new algorithms were then compared to actual thunderstorm start times to determine which method produced the most accurate results. The average thunderstorm starting time was also calculated from the data. This time was also compared to actual thunderstorm starting time. Upon examination of the various start times produced, it was …


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

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

Theses and Dissertations

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


Descriptive And Conditional Climatology For Specific Launch Commit Criteria For Cape Canaveral, Florida, Edward C. Goetz Mar 2000

Descriptive And Conditional Climatology For Specific Launch Commit Criteria For Cape Canaveral, Florida, Edward C. Goetz

Theses and Dissertations

In 1987, an unmanned Atlas-Centaur-67 launched from the Cape triggered a lightning discharge that disabled the on-board guidance system and Range Control destroyed the platform. This incident spurred the review and revision of the natural and triggered lightning launch commit criteria (LCC). The LCC are a set of eleven complex rules that are constantly evaluated by the Launch Weather Team (LWT) of 45th Weather Squadron (45WS). Unfortunately, the 45WS LWT does not have either a descriptive or conditional climatology for many of the LCC. This thesis addresses the lightning and the cumulus LCC. A descriptive climatology for both the lightning …


Chromate Dissociation From Primer Paint In Simulated Lung Fluid, Tiffany J. R. Morgan Mar 2000

Chromate Dissociation From Primer Paint In Simulated Lung Fluid, Tiffany J. R. Morgan

Theses and Dissertations

OSHA has proposed a new strontium chromate exposure standard that would potentially cause Air Force paint facilities to be in violation of the proposed standard if adopted. This proposed reduction make the continued use of chromate containing primer paints very difficult. There is currently no acceptable replacements for chromate containing primer paints on AF aircraft. This study suggests that paint particles with chromate bound in primer paint may be unavailable for bodily absorption if inhaled and a reduced standard for painting applications may be unnecessary. Primer paint overspray was collected into simulated lung fluid (SLF) and allowed 6 hr, 24 …


Optical Metrology Of Adaptive Membrane Mirrors, John W. Wagner Mar 2000

Optical Metrology Of Adaptive Membrane Mirrors, John W. Wagner

Theses and Dissertations

Current space-based imaging platforms are significantly constrained in both size and weight by the launch vehicle. Increased payload size and weight results in increased cost and a decrease in launch responsiveness. The USAF Scientific Advisory Board (SAB) identified "Large lightweight structures for optics and antennas" as a revolutionary primary technology to be developed for the Air Force of the 21st Century. A membrane primary mirror in a space-based imaging system has the ability to overcome current payload constraints and meet evolutionary needs of the future. The challenge of membrane optics in space is the process of implementing adaptive optics technology …


A Comparative Analysis Of Cockpit Display Development Tools, Matthew J. Gebhardt Mar 2000

A Comparative Analysis Of Cockpit Display Development Tools, Matthew J. Gebhardt

Theses and Dissertations

Currently, no standard methodology exists that enables cockpit display engineers to evaluate software tools used in the development of graphical cockpit displays. Furthermore, little research has been accomplished in comparing current software development tools with traditional hand-coded methods, This research effort discusses a framework for analyzing cockpit display software development tools and follows through with a detailed analysis comparing today's hand-coding standard, OpenGL, with two of today's cockpit display software development suites, Virtual Application Prototyping System (VAPS) and Display Editor. The comparison exploits the analysis framework establishing the advantages and disadvantages of the three software development suites. The analysis framework …


A Human-Centered Approach For Designing Decision Support Systems, Sean G. Kern Mar 2000

A Human-Centered Approach For Designing Decision Support Systems, Sean G. Kern

Theses and Dissertations

The choice to include the human in the decision process affects four key areas of system design: problem representation, system analysis and design, solution technique selection, and interface requirements specification. I introduce a design methodology that captures the necessary choices associated with each of these areas. In particular I show how this methodology is applied to the design of an actual decision Support system for satellite operations scheduling. Supporting the user's ability to monitor the actions of the system and to guide the decision process of the system are two key considerations in the successful design of a decision support …


Testing Of The New Usgs K Index Algorithm At Bear Lake Observatory, Ariel O. Acebal Mar 2000

Testing Of The New Usgs K Index Algorithm At Bear Lake Observatory, Ariel O. Acebal

Theses and Dissertations

The K index was developed by Bartels in 1939 as an estimate of the level of geomagnetic activity caused by the Sun. This index was computed manually every three hours at geomagnetic observatories using the magnetic traces of the surface planetary magnetic field. In 1991, the International Association of Geomagnetism and Aeronomy approved four additional methods to compute the K index; all of them were computer algorithms. One of the approved methods, the Wilson code, recently underwent some modifications. The new algorithm is now part of a Windows-based computer program being developed by the United States Geological Survey (USGS). After …


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

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

Theses and Dissertations

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


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

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

Theses and Dissertations

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


A Method Of Focusing The Attention Of The Decision-Maker On Uncertain Information, John F. Moesner Iv Mar 2000

A Method Of Focusing The Attention Of The Decision-Maker On Uncertain Information, John F. Moesner Iv

Theses and Dissertations

Military decision-makers need to be able to synthesize large amounts of information quickly and make accurate and timely decisions. However, all too often, when a decision-maker is bombarded with important information that has an uncertainty associated with it, that information is often neglected. One method of dealing with this type of information overload is through proper data orientation. By reducing the clutter of irrelevant information, the proportions of useful and relevant data can be increased. At the same time, the attention of the decision-maker is directed to the critical tasks or centers of gravity. The WATCHDOG Decision Support Tool is …


A Component Based Approach To Agent Specification, David J. Robinson Mar 2000

A Component Based Approach To Agent Specification, David J. Robinson

Theses and Dissertations

The Air Force, as well as all of industry, is currently faced with the problem of having to produce larger and more complex software systems that run efficiently and reliably as well as being extensible and maintainable. This research addresses this problem by developing a knowledge representation language that can be used to unambiguously specify and design software systems in a verifiable, efficient, and understandable manner. The language is a combination of object-oriented and component-based methodologies and makes use of both graphics and text to represent information. Although designed for the development of any type of software system, the language …


Multiagent Systems Engineering: A Methodology For Analysis And Design Of Multiagent Systems, Mark F. Wood Mar 2000

Multiagent Systems Engineering: A Methodology For Analysis And Design Of Multiagent Systems, Mark F. Wood

Theses and Dissertations

This thesis defines a methodology for the creation of multiagent systems, the Multiagent Systems Engineering (MaSE) methodology. The methodology is a key issue in the development of any complex system and there is currently no standard or widely used methodology in the realm of multiagent systems. MaSE covers the entire software lifecycle, starting from an initial prose specification, and creating a set of formal design documents in a graphical style based on a formal syntax. The final product of MaSE is a diagram describing the deployment of a system of intelligent agents that communicate through structured conversations. MaSE was created …


Stochastic Modeling-Based Dgps Estimation Algorithm, James T. Broaddus Mar 2000

Stochastic Modeling-Based Dgps Estimation Algorithm, James T. Broaddus

Theses and Dissertations

A Kinematic Differential Global Positioning System (KDGPS) algorithm is developed. A number of mobile receivers is considered, one of which will be designated the reference station' which will have known position and velocity information at the beginning of the time interval examined. Satellite clock biases are used to model Selective Availability. The measurement situation on hand is properly modeled and a centralized estimation algorithm processing several epochs of data. The effect of uncertainty in the reference receiver's position and the level of receiver noise is examined. Monte Carlo simulations are performed to examine the ability of the algorithm to correctly …