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2000

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Feature Selection For Predicting Pilot Mental Workload, Julia A. East Mar 2000

Feature Selection For Predicting Pilot Mental Workload, Julia A. East

Theses and Dissertations

Advances in technology have the cockpits of the aircraft in the Air Force inventory increasingly complex. Consequently, mental demands on the pilot have risen. In some cases, mental demands were so overwhelming that pilots have forgotten basic flying techniques, such as G-straining maneuvers. The results have been fatal. Recent research in this area has involved collecting psychophysiological features, such as electroencephalography (EEG), heart, eye and respiration measures, in an attempt to identify pilot mental workload. This thesis focuses on feature selection and reduction of the psycophysiological features and subsequent classification of pilot mental workload on multiple subjects over multiple days. …

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Effects Of Moisture Content In Solid Waste Landfills, Craig P. Eck Mar 2000

Effects Of Moisture Content In Solid Waste Landfills, Craig P. Eck

Theses and Dissertations

Solid waste landfills are an extremely complex and heterogeneous environment. Modeling the biodegradation processes within a landfill must involve an understanding of how environmental factors affect these processes. Arguably, the most important environmental factor influencing biodegradation processes is solid waste moisture content. This research effort, which is an extension of a system dynamics model previously presented by Colborn (1997) and amended by Benter (1999), attempts to understand and model the effects of moisture content on waste degradation and landfill gas generation. The new moisture structure that was added to the previous models provides a better representation of the impact of …

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Multi-Objective Evaluation Of Target Sets In A Logistics Network, Paul D. Emslie Mar 2000

Multi-Objective Evaluation Of Target Sets In A Logistics Network, Paul D. Emslie

Theses and Dissertations

This thesis addresses the selection of target sets to disrupt an adversary's logistics network in a wartime environment. In the presence of many objectives--such as reducing maximum flow, lengthening routes, avoiding collateral damage, all at minimal risk to our pilots--the problem of determining the best target set is complex. Previous efforts have not adequately considered the value of the remaining network functionality after target destruction. In addition, current network targeting procedures optimize target sets with respect to only a single metric. This thesis uses a multi-objective decision analysis framework capturing actual targeting decision-maker values and preferences to evaluate and analyze …

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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 …

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Global Positioning System (Gps) Error Source Prediction, Marcus G. Ferguson Mar 2000

Global Positioning System (Gps) Error Source Prediction, Marcus G. Ferguson

Theses and Dissertations

With the initiation of the navigation accuracy prediction algorithm used to estimate the amount of GPS solution (location and time) error for receivers, the capability to accurately predict solution errors due to the major GPS error sources is growing. Although some sources of error within the GPS solution have been previously analyzed, modeled, and/or accounted for within various modeling efforts, a formal evaluation of the seven major error sources that distort GPS activity has not been officially conducted up until this point. This research offers a logical assessment of all the major GPS error sources and their definitive impact on …

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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.

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Integrating Automated Multi-Disciplinary Optimization In Preliminary Design Of Non-Traditional Aircraft, Mehmet Fidanci, Jeffrey R. Miller, Douglas J. Strauss Mar 2000

Integrating Automated Multi-Disciplinary Optimization In Preliminary Design Of Non-Traditional Aircraft, Mehmet Fidanci, Jeffrey R. Miller, Douglas J. Strauss

Theses and Dissertations

Current methods of aircraft conceptual design lack the ability to quickly generate detailed analysis, particularly of nontraditional designs such as blended wing body craft. This study developed a method to resolve this problem by creating a flexible, parametrically driven conceptual model in an object-oriented, adaptive modeling environment from which analysis and optimization may rapidly be performed. These object-oriented techniques are incorporated into a traditional conceptual design process. All objects inherit dependency-tracking and demand-driven calculations. Design Analysis was performed within the modeling language and utilized interfaces to other software packages. A detailed mesh, suitable for input into finite element analysis programs, …

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Chromium Concentration Bias In The Particle Size Distribution Of Primer Overspray, Joseph M. Fox Mar 2000

Chromium Concentration Bias In The Particle Size Distribution Of Primer Overspray, Joseph M. Fox

Theses and Dissertations

Air Force aircraft-painting operations create clouds of paint overspray that contain strontium chromate, a confirmed carcinogen, which poses an exposure hazard to painters. It is often assumed that all particles in paint overspray have the same chemical composition as the original paint mixture, however differences in composition may occur in various particle sizes. Because particle size affects where in the respiratory system a particle deposits, actual exposures to a specific chemical may vary. Paint particles greater than 2.5 µm are deposited in the upper respiratory system and will be eliminated by physiological removal mechanisms. Particles less than 2.5 µm will …

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Attitude Control And Multimedia Representation Of Air Force Institute Of Technology’S (Afit’S) Simulation Satellite (Simsat), Joseph M. Fulton Mar 2000

Attitude Control And Multimedia Representation Of Air Force Institute Of Technology’S (Afit’S) Simulation Satellite (Simsat), Joseph M. Fulton

Theses and Dissertations

This document describes the systematic construction of the AFIT-sponsored program to develop a laboratory-based satellite simulator. The simulation satellite (SIMSAT) system will provide a useful tool for resident staff while teaching attitude control concepts. A brief overview of attitude control theory is provided as well as a discussion of the benefits of multimedia use in education. A detailed discussion of the satellite's components allows the reader to become familiar with each piece of SIMSAT. Software control models are provided as well as a multimedia lesson plan on satellite attitude control. Also included in this document are potential experimental uses in …

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Damage Identification In A Real Structure Using Resonant And Anti-Resonant Frequencies, Douglas E. Gaeta Mar 2000

Damage Identification In A Real Structure Using Resonant And Anti-Resonant Frequencies, Douglas E. Gaeta

Theses and Dissertations

There exists a need to remotely monitor the structural integrity of large space structures without costly manned missions. This work focused on further damage detection characterization of the Air Force Institute of Technology's Flexible Truss Experiment (FTE). The FTE is intended to be representative of a large space structure. Several damage detection algorithms were developed and tested for the FTE using 112 different damage conditions and the one undamaged condition. The algorithms were trained using two frequency response functions (FRFs) from each damage case and then tested using the same two FRFs, but from newly acquired data. A data reduction …

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Analysis Of Uh-60 Blackhawk Safety Controls Using Value Focused Thinking And Monte Carlo Simulation, Roger D. Gallan Jr. Mar 2000

Analysis Of Uh-60 Blackhawk Safety Controls Using Value Focused Thinking And Monte Carlo Simulation, Roger D. Gallan Jr.

Theses and Dissertations

In the past few years, Army aviation accidents have been on the rise, due largely to increases in mission frequency and complexity, and diminishing resources. The magnitude of the resulting losses (casualties, dollars, equipment) has prompted the Commanding General of the Army Safety Center to demand a complete examination of the way safety hazards and subsequent safety controls are evaluated and selected. This project integrates value focused thinking, Monte Carlo simulation, and integer programming in response to this demand by developing and using a methodology that effectively identifies and evaluates portfolios of controls. An integer program generates portfolios of controls …

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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 …

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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 …

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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 …

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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 …

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Three Dimensional Formation Flight Control, James K. Hall Mar 2000

Three Dimensional Formation Flight Control, James K. Hall

Theses and Dissertations

Automating the control of an aircraft flying in formation necessitates the extension of the theory of formation flight control to allow for three dimensional maneuvers. The formation was modeled as a two-aircraft, leader and wingspan, formation. Both aircraft has its own three dimensional, rotating and translating, Cartesian axes system, with special attention being given to the motion of the leader in relation to the wingspan. The controller operated using the equations of motion expressed in the rotating reference frame of the wing aircraft. The control system has seven states, three inputs and three disturbance signals to model the dynamics of …

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A Group Theoretic Tabu Search Approach To The Traveling Salesman Problem, Shane N. Hall Mar 2000

A Group Theoretic Tabu Search Approach To The Traveling Salesman Problem, Shane N. Hall

Theses and Dissertations

The traveling salesman problem (TSP) is a combinatorial optimization problem that is mathematically modeled as a binary integer program. The TSP is a very important problem for the operations research academician and practitioner. This research demonstrates a Group Theoretic Tabu Search (GTTS) Java algorithm for the TSP. The tabu search metaheuristic continuously finds near-optimal solutions to the TSP under various different implementations. Algebraic group theory offers a more formal mathematical setting to study the TSP providing a theoretical foundation for describing tabu search. Specifically, this thesis uses the Symmetric Group on n letters, S(n), which is the set of all …

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A Java Universal Vehicle Router In Support Of Routing Unmanned Aerial Vehicles, Robert W. Harder Mar 2000

A Java Universal Vehicle Router In Support Of Routing Unmanned Aerial Vehicles, Robert W. Harder

Theses and Dissertations

Unmanned Aerial Vehicles (UAVs) help the military gather information in times of peace and war. During a mission, typically 100 sites or more, a UAV will frequently be re-tasked to visit a pop-up threat, leaving the operator to determine the best way to finish the day's list of sites after the re-tasking. I develop a prototype application to serve the needs of a specific customer, the 11th Reconnaissance Squadron, by helping them preplan missions and dynamically re-task UAVs. This prototype application is built on a reusable airframe router called the core AFIT Router, which can later be added to more …

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A Distributed Agent Architecture For A Computer Virus Immune System, Paul K. Harmer Mar 2000

A Distributed Agent Architecture For A Computer Virus Immune System, Paul K. Harmer

Theses and Dissertations

Information superiority is identified as an Air Force core competency and is recognized as a key enabler for the success of future missions. Information protection and information assurance are vital components required for achieving superiority in the Infosphere, but these goals are threatened by the exponential birth rate of new computer viruses. The increased global interconnectivity that is empowering advanced information systems is also increasing the spread of malicious code and current anti-virus solutions are quickly becoming overwhelmed by the burden of capturing and classifying new viral stains. To overcome this problem, a distributed computer virus immune system (CVIS) based …

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Analysis Of The Air Force Iso 14001 Pilot Study Conducted By Dod, Rodney C. Harris Mar 2000

Analysis Of The Air Force Iso 14001 Pilot Study Conducted By Dod, Rodney C. Harris

Theses and Dissertations

The Department of Defense (DoD) conducted an ISO 14001 pilot study with the primary goal of determining how ISO 14001 could help DoD organizations reduce risks, improve compliance with environmental regulations, enhance stewardship, contain costs, and meet emerging regulatory requirements. This thesis analyzed the pilot study, specifically looking at the ISO 14001 implementation at three Air Force installations participating in the study. The research objectives were to identify factors that affect implementation of ISO 14001, compare the implementation strategies used by the bases, and develop propositions for Air Force managers to consider when implementing ISO 14001. Interviews of key personnel, …

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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 …

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Techniques For Forecasting The Cessation Of Lightning At Cape Canaveral Air Station And The Kennedy Space Center, Michael W. Holmes Mar 2000

Techniques For Forecasting The Cessation Of Lightning At Cape Canaveral Air Station And The Kennedy Space Center, Michael W. Holmes

Theses and Dissertations

The focus of this research effort is directed toward identifying new methods of forecasting the cessation of lightning along the Central Atlantic Coast of Florida. Cloud-to-ground lightning flashes place Air Force (AF) personnel and assets at risk almost daily at this location. Providing a more accurate method of forecasting the cessation of lightning would allow for safer and more efficient execution of AF operations. A data set consisting of 40 thunderstorm cases was identified within a 90 nautical miles (nmi) region surrounding the Melbourne, Florida WSR-88D (KMLB) site. Each case falls between the months of May and September and the …

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An Object-Oriented Approach To The Modeling And Visualization Of Breast Cancer Tumors, Bruce C. Jenkins Mar 2000

An Object-Oriented Approach To The Modeling And Visualization Of Breast Cancer Tumors, Bruce C. Jenkins

Theses and Dissertations

Great strides have been made in controlling the progression of breast cancer, but medical professionals continue to rely primarily upon traditional mammography for early detection. Enhancing breast cancer detection capabilities - and thus reducing tumor detection time - should result in a reduction in mortality rates. The detection capabilities of mammography may be enhanced through improved modeling and visualization techniques. This thesis is an extension of initial research conducted at the Air Force Institute of Technology. Previous efforts focused on developing a mathematical model for simulating the growth of cancer within unconstrained 3-dimensional space. The research also explored the behavior …

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Data Warehouse Techniques To Support Global On-Demand Weather Forecast Metrics, Meriellen C. Joga Mar 2000

Data Warehouse Techniques To Support Global On-Demand Weather Forecast Metrics, Meriellen C. Joga

Theses and Dissertations

Air Force pilots and other operators make crucial mission planning decisions based on weather forecasts; therefore, the ability to forecast the weather accurately is a critical issue to Air Force Weather (AFW) and its customers. The goal of this research is to provide Air Force Weather with a methodology to automate statistical data analysis for the purpose of providing on-demand metrics. A data warehousing methodology is developed and applied to the weather metrics problem in order to present an option that will facilitate on-demand metrics. On-line analytical processing (OLAP) and data mining solutions are also discussed.

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Toward Validating Vertical Aggregation In Object Oriented Simulation, George W. Johnson Jr. Mar 2000

Toward Validating Vertical Aggregation In Object Oriented Simulation, George W. Johnson Jr.

Theses and Dissertations

Recent interest in studying the nonlinear effects of intelligence, surveillance, and reconnaissance in combat models has prompted researchers to employ vertical aggregation in object-oriented simulations. Traditional horizontal aggregation falls short for its inability to provide accurate means for nonlinear functions. Averaging a group of objects that exhibit nonlinear behavior provides a linear approximation to the mean, which is not necessarily the expected value of the underlying nonlinear function. Vertical aggregation explicitly models individual objects, thus preserving their nonlinear behaviors. In this research, a validation procedure is derived to study the aptness of vertical aggregation methods. Validation is carried out by …

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Finite Element Model Updating Using Antiresonant Frequencies, Keith W. Jones Mar 2000

Finite Element Model Updating Using Antiresonant Frequencies, Keith W. Jones

Theses and Dissertations

The applications of antiresonant frequencies to finite element (FE) model updating are few and usually limited to numerical examples. This work uses antiresonant frequencies in the model updating of an experimental structure and analyzes the physical correctness of the updated model by using it to detect damage. Antiresonant frequencies were used in the FE model updating of a six-meter aluminum truss. The model used rigid links to model welded and bolted joints. Rigid link dimensions were used as parameters in an iterative update based on eigenvalue and antiresonance sensitivities. The first update used 11 natural frequencies and 21 antiresonant frequencies …

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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 …

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A Hybrid Jump Search And Tabu Search Metaheuristic For The Unmanned Aerial Vehicle (Uav) Routing Problem, Gary W. Kinney Jr. Mar 2000

A Hybrid Jump Search And Tabu Search Metaheuristic For The Unmanned Aerial Vehicle (Uav) Routing Problem, Gary W. Kinney Jr.

Theses and Dissertations

In this research, we provide a new meta-heuristic, a jump search I tabu search hybrid, for addressing the vehicle routing problem with real-life constraints. A tour construction heuristic creates candidate solutions or jump points for the problem. A tabu search algorithm uses these jump points as starting points for a guided local search. We provide statistical analysis on the performance of our algorithm and compare it to other published algorithms. Our algorithm provides solutions within 10% of the best known solutions to benchmark problems and does so in a fraction of the time required by competing algorithms. The timeliness of …

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An Information Visualization Solution For The Analysis Of The Afm Simulation Output Data, Stuart H. Kurkowski Mar 2000

An Information Visualization Solution For The Analysis Of The Afm Simulation Output Data, Stuart H. Kurkowski

Theses and Dissertations

With the advancement of computer hardware and software computer simulations are now able to run faster and track more elements than ever before burdening the analyst with more and more data to analyze. Air Mobility Command's (AMC) Airlift Flow Model (AFM) is the Air Force's logistics simulator that simulates multi-day mobility scenarios in a matter of minutes producing megabytes of output data. Because the analysts' needs for summaries, trends, and comparisons of the data have surpassed the capabilities of current desktop spreadsheet analysis techniques new tools are needed.

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A Formal Methodology And Technique For Verifying Communication Protocols In A Multi-Agent Environment, Timothy H. Lacey Mar 2000

A Formal Methodology And Technique For Verifying Communication Protocols In A Multi-Agent Environment, Timothy H. Lacey

Theses and Dissertations

As network bandwidth increases, distributed applications are becoming increasingly prevalent. Systems using these applications are very complicated to build and must be dependable. Software agents are ideal for breaking complicated problems into manageable subtasks. Agent conversations, a series of messages passed between agents, are the cornerstone of multi-agent systems and must be deemed correct before being placed into service. The purpose of this research was to develop a formal methodology and technique to verify that the communication protocols defined in a multi-agent environment were valid. This was accomplished by examining agent conversations before deploying the system. An additional goal of …

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