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The Practitioner From Within: Revisiting The Virtues, Frances Grodzinsky Mar 1999

The Practitioner From Within: Revisiting The Virtues, Frances Grodzinsky

School of Computer Science & Engineering Faculty Publications

Traditionally the study of computer ethics involves taking students who are not philosophically trained, exposing them to action-guiding theories, presenting them with the codes of ethics of several companies and professional organizations and asking them to make ethical decisions in scenario-based cases. This approach is deliberately action-based and focuses on doing. "What would you do?" is the traditional question we ask our students. While this pedagogical methodology forces them to examine situations and argue from a particular point of view, it does little to influence their character. They see the utilitarian or deontologist as someone other than themselves. There seems …

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A Constructive Induction Approach To Computer Immunology, Kelley J. Cardinale, Hugh M. O'Donnell Mar 1999

A Constructive Induction Approach To Computer Immunology, Kelley J. Cardinale, Hugh M. O'Donnell

Theses and Dissertations

With the increasing birth rate of new viruses and the rise in interconnectivity and interoperability among computers, the burden of detecting and destroying computer viruses is severe. This research integrated four domains: computer virus detection, human immunology, computer immunology and an automated form of machine learning called constructive induction. First, a Computer Health System, based on the public health system, was defined to improve the 'global' approach to computer virus protection. Second, a computer immune model, based on the human immune system, was defined to improve the 'local' approach to virus detection. Third, the detection component of this computer immune …

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An Interactive Tool For Refining Software Specifications From A Formal Domain Model, Gary L. Anderson Mar 1999

An Interactive Tool For Refining Software Specifications From A Formal Domain Model, Gary L. Anderson

Theses and Dissertations

This work examines the process for refining a software specification from a formal object-oriented domain model. This process was implemented with interactive software to demonstrate the feasibility and benefits of automating what has been a tedious and often error-prone manual task. The refinement process operates within the framework of a larger Knowledge-Based Software Engineering system. A generic object-oriented representation is used to store a domain model, which allows the specification tool to access, select, and manipulate the required objects to form a customized specification. The specification is also stored as an object-oriented model, which in turn can be accessed by …

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A Java Based Human Computer Interface For A Uav Decision Support Tool Using Conformal Mapping, Randy A. Flood Mar 1999

A Java Based Human Computer Interface For A Uav Decision Support Tool Using Conformal Mapping, Randy A. Flood

Theses and Dissertations

This paper describes the development of the Human Computer Interface (HCI) for a Decision Support System for routing Unmanned Aerial Vehicles (UAVs). This problem is a multi-vehicle routing problem with time-windows. Because of the unique nature of UAVs, a tool is needed to support dynamic re-routing. We solve the problem in two ways. First, we create a UAV Decision Support Tool (UAV DST) that uses a set of Java software objects to display maps and convert between latitude-longitude coordinates and x-y coordinates. Secondly, this library provides the ability for the user to dynamically reoptimize large UAV routing problems through a …

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Protein Structure Prediction Using Parallel Linkage Investigating Genetic Algorithms, Karl R. Deerman Mar 1999

Protein Structure Prediction Using Parallel Linkage Investigating Genetic Algorithms, Karl R. Deerman

Theses and Dissertations

AFIT has had a long-standing interest in solving the protein structure prediction (PSP) problem. The PSP problem is an intractable problem that if "solved" can lead to revolutionary new techniques for everything from the development of new medicines to optical computer switches. The challenge is to find a reliable and consistent method of predicting the 3-dimensional structure of a protein given its defining sequence of amino acids. PSP is primarily concerned with predicting the tertiary protein structure without regards to how the protein came to this folded state. The tertiary structure determines the protein's functionality.

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Strategies For Steganalysis Of Bitmap Graphics Files, Christopher J. Fogle Mar 1999

Strategies For Steganalysis Of Bitmap Graphics Files, Christopher J. Fogle

Theses and Dissertations

Steganography is the art and science of communicating through covert channels. The goal of steganography is to hide the fact that a message is even being transmitted. In the context of today's digital world, this ancient practice is enjoying resurgence due to the plethora of hiding places made possible by modern information media. Of particular concern is the use of graphics image files to conceal both legitimate and criminal communications.

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Parallel Data Mining With The Message Passing Interface Standard On Clusters Of Personal Computers, Lonnie P. Hammack Mar 1999

Parallel Data Mining With The Message Passing Interface Standard On Clusters Of Personal Computers, Lonnie P. Hammack

Theses and Dissertations

Piles of personal computers (PoPCs) have begun to challenge the performance of the traditional Massively Parallel Processors (MPPs) and the less traditional networks of workstations (NOWs) as platforms for parallel computing. Large clusters of PCs have reached and at times exceeded the performance of modern MPPs at a fraction of the cost. Built with commodity components, these clusters can be constructed for about half the cost of a comparable NOW. The primary competing operating systems (OIS) in use on PoPCs are Linux and Windows NT. This thesis investigation compares the performance of an NT cluster with that of a Linux …

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Target Pose Estimation From Radar Data Using Adaptive Networks, Andrew W. Learn Mar 1999

Target Pose Estimation From Radar Data Using Adaptive Networks, Andrew W. Learn

Theses and Dissertations

his research investigates and extends recent work by J.C. Principe at the University of Florida in target pose estimation using adaptive networks. First, Principe's technique is successfully extended to estimate both azimuth and elevation using SAR images. A network trained and tested using MSTAR data yields mean errors of less than six degrees in azimuth and five degrees in elevation. Second, the technique is applied to high-range resolution radar (HRR) signatures. Ground target (azimuth only) testing yields mean errors of less than 11 degrees for most classes. Air target testing for networks trained and tested on the same aircraft class …

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A Modeling And Simulation Approach To Analyze The Workload Associated With The Growth Of Network Router Access Control Lists, Douglas R. Lomsdalen Mar 1999

A Modeling And Simulation Approach To Analyze The Workload Associated With The Growth Of Network Router Access Control Lists, Douglas R. Lomsdalen

Theses and Dissertations

Organizations can no longer isolate their networks from the rest of the world and still remain competitive. An organization willing to compete in the world market must take the necessary precautions to protect its network, the systems located on those networks, and its mission critical data. There are performance issues associated with the use of access control lists (ACL); however, if ACLs are implemented properly and periodically reviewed, a secure network can be attained. This research attempts to determine how the growth of an ACL affects packet flow and router CPU consumption, and also identify the specific length of an …

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Extensible Multi-Agent System For Heterogeneous Database Association Rule Mining And Unification, Christopher G. Marks Mar 1999

Extensible Multi-Agent System For Heterogeneous Database Association Rule Mining And Unification, Christopher G. Marks

Theses and Dissertations

The Probabilities, Expert System, Knowledge, and Inference (PESKI) System uses the data mining of association rules to fill incompleteness in the knowledge of an expert system. The rules are mined from transactional data sources and then incorporated using an existing link to PESKI. One method of providing a system that will easily allow new data sources to be added is using an information gathering agent-based system. This research first develops a methodology for designing and creating a multi-agent system. It then applies this methodology to design a platform independent means of data mining data sources of any format. The use …

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A Structured Approach To Software Tool Integration, Penelope A. Noe Mar 1999

A Structured Approach To Software Tool Integration, Penelope A. Noe

Theses and Dissertations

As the trend towards commercial off-the-shelf (COTS) software continues, civilian companies and government agencies alike are battling with the challenge of making multiple software packages and applications work together. Many of these companies and agencies have attempted to integrate the software tools to form a coherent system that satisfies their goals, often without the use of a step by step approach guiding the effort. Many researchers in the field of software tool integration have determined the areas that need to be addressed when tools are integrated. Some researchers have developed and expanded upon a theoretical model for integration. This model …

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Incorporating Scene Mosaics As Visual Indexes Into Uav Video Imagery Databases, Timothy I. Page Mar 1999

Incorporating Scene Mosaics As Visual Indexes Into Uav Video Imagery Databases, Timothy I. Page

Theses and Dissertations

The rise of large digital video archives has strengthened the need for more efficient ways of indexing video files an accessing the information contained in them. Reconnaissance platforms, such as the Predator UAV, are contributing thousands of hours of video footage that require analysis, storage, and retrieval. A process is proposed for converting a video stream into a series of mosaic and selected still images that provide complete coverage of the original video. The video mosaic images can be utilized as visual indexes into a video database. In addition, mosaic images contain information from an entire sequence of video frames …

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Analysis Of The Applicability Of Video Segmentation To Unmanned Aerial Vehicle Surveillance Video, Bradley L. Pyburn Mar 1999

Analysis Of The Applicability Of Video Segmentation To Unmanned Aerial Vehicle Surveillance Video, Bradley L. Pyburn

Theses and Dissertations

The focus of this research is to determine if applying edge detection segmentation (proposed by Ramin Zabih, Justin Miller, and Kevin Mai) to Unmanned Aerial Vehicle (UAV) video footage can provide meaningful segments for database storage and retrieval. The edge detection segmentation algorithm is applied to fifty-four UAV video sequences containing visual effects such as abrupt camera changes, camera zooms, motion (rapid and gradual), and cloud cover while varying the frame rate from 5 fps to 30 fps. An analysis of the results is performed to compare actual versus expected outcomes, similar sequences, and scenes with motion, along with explaining …

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An Efficient Gps Position Determination Algorithm, Carlos R. Colon Mar 1999

An Efficient Gps Position Determination Algorithm, Carlos R. Colon

Theses and Dissertations

The use of detect, or closed-form solutions of the trilateration equations used to obtain the position fix in GPS receivers is investigated. The paper is concerned with the development of an efficient new position determination algorithm that uses the closed-form solution of the trilateration equations and works in the presence of pseudorange measurement noise and for an arbitrary number of satellites. in addition, an initial position guess is not required and good estimation performance is achieved even under high GDOP conditions. A two step GPS position determination algorithm which 1) entails the solution of a linear regression problem and, 2) …

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Computation Of Scattering From Bodies Of Revolution Using An Entire-Domain Basis Implementation Of The Moment Method, Arthur P. Ford Iv Mar 1999

Computation Of Scattering From Bodies Of Revolution Using An Entire-Domain Basis Implementation Of The Moment Method, Arthur P. Ford Iv

Theses and Dissertations

Research into improved calibration targets for measurement of radar cross-section has created a need for the ability to accurately compute the scattering from perfectly conducting bodies of revolution. Common computational techniques use Moment Method codes that employ subdomain basis functions to expand the unknown current density. This approach has its shortcomings. Large numbers of basis functions are required, and increasing the number of basis functions to improve accuracy after an initial computation requires re-computation of previous results and lost processing time. This research involves using basis functions that have as their domain the entire length of the surface. Entire-domain basis …

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Graphical User Interface And Microprocessor Control Enhancement Of A Pseudorandom Code Generator, John M. Kos Mar 1999

Graphical User Interface And Microprocessor Control Enhancement Of A Pseudorandom Code Generator, John M. Kos

Theses and Dissertations

Modern digital communication techniques often require the generation of pseudorandom numbers or sequences. The ability to quickly and easily produce various codes such as maximal length codes, Gold codes, Jet Propulsion Laboratory ranging codes, syncopated codes, and non-linear codes in a laboratory environment is essential. This thesis addresses the issue of providing automated computer control to previously built, manually controlled hardware incorporating the Stanford Telecom STEL-1032 Pseudo-Random Number (PRN) Coder. By incorporating a microcontroller into existing hardware, the STEL-1032 can now be conveniently controlled from a MATLAB Graphical User Interface (GUI). The user can quickly create, save, and recall various …

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Prestructuring Neural Networks Via Extended Dependency Analysis With Application To Pattern Classification, George G. Lendaris, Thaddeus T. Shannon, Martin Zwick Mar 1999

Prestructuring Neural Networks Via Extended Dependency Analysis With Application To Pattern Classification, George G. Lendaris, Thaddeus T. Shannon, Martin Zwick

Complex Systems Faculty Publications and Presentations

We consider the problem of matching domain-specific statistical structure to neural-network (NN) architecture. In past work we have considered this problem in the function approximation context; here we consider the pattern classification context. General Systems Methodology tools for finding problem-domain structure suffer exponential scaling of computation with respect to the number of variables considered. Therefore we introduce the use of Extended Dependency Analysis (EDA), which scales only polynomially in the number of variables, for the desired analysis. Based on EDA, we demonstrate a number of NN pre-structuring techniques applicable for building neural classifiers. An example is provided in which EDA …

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Can Kiva Accurately Simulate A Gas Turbine Combustor?, John R. Rice Mar 1999

Can Kiva Accurately Simulate A Gas Turbine Combustor?, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

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Visualizing Three-Dimensional Configuration Spaces For Mechanical Design, Elisha Sacks, Charles Pisula, Leo Joskowicz Mar 1999

Visualizing Three-Dimensional Configuration Spaces For Mechanical Design, Elisha Sacks, Charles Pisula, Leo Joskowicz

Department of Computer Science Technical Reports

No abstract provided.

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Least Squares Approximation Of Bezier Coefficients Provides Best Degree Reduction In The L 2-Norm, J. Peters, U Reif Mar 1999

Least Squares Approximation Of Bezier Coefficients Provides Best Degree Reduction In The L 2-Norm, J. Peters, U Reif

Department of Computer Science Technical Reports

No abstract provided.

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Texture Analysis Of Sar Sea Ice Imagery Using Gray Level Co-Occurrence Matrices, Leen-Kiat Soh, Costas Tsatsoulis Mar 1999

Texture Analysis Of Sar Sea Ice Imagery Using Gray Level Co-Occurrence Matrices, Leen-Kiat Soh, Costas Tsatsoulis

School of Computing: Faculty Publications

This paper presents a preliminary study for mapping sea ice patterns (texture) with 100-m ERS-1 synthetic aperture radar (SAR) imagery. We used gray-level co-occurrence matrices (GLCM) to quantitatively evaluate textural parameters and representations and to determine which parameter values and representations are best for mapping sea ice texture. We conducted experiments on the quantization levels of the image and the displacement and orientation values of the GLCM by examining the effects textural descriptors such as entropy have in the representation of different sea ice textures. We showed that a complete gray-level representation of the image is not necessary for texture …

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Segmentation Of Satellite Imagery Of Natural Scenes Using Data Mining, Leen-Kiat Soh, Costas Tsatsoulis Mar 1999

Segmentation Of Satellite Imagery Of Natural Scenes Using Data Mining, Leen-Kiat Soh, Costas Tsatsoulis

School of Computing: Faculty Publications

In this paper, we describe a segmentation technique that integrates traditional image processing algorithms with techniques adapted from knowledge discovery in databases (KDD) and data mining to analyze and segment unstructured satellite images of natural scenes. We have divided our segmentation task into three major steps. First, an initial segmentation is achieved using dynamic local thresholding, producing a set of regions. Then, spectral, spatial, and textural features for each region are generated from the thresholded image. Finally, given these features as attributes, an unsupervised machine learning methodology called conceptual clustering is used to cluster the regions found in the image …

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Analysis Of Usaf Battlelabs' Communication Infrastructure Over Various Protocols, Rocky A. Favorito, David M. Mcillece Mar 1999

Analysis Of Usaf Battlelabs' Communication Infrastructure Over Various Protocols, Rocky A. Favorito, David M. Mcillece

Theses and Dissertations

As a result of the doctrines exposed in the Air Force's "Global Engagement: A Vision for the 21st Century Air Force," the concept of a "Battlelab" was devised to support and develop the key warfighting capabilities needed in the next century. Although geographically separated, these labs must have the capability to exchange information with each other in a "Virtual Battlelab Environment" (VBE). Although many types of data will be exchanged, only variable-bit-rate (VBR) video and distributed interactive simulation (DIS) traffic are modeled in the VBE. The research described in this thesis utilizes a systems engineering approach to investigate the performance …

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Methodology For Application Design Using Information Dissemination And Active Database Technologies, Robert H. Hartz Mar 1999

Methodology For Application Design Using Information Dissemination And Active Database Technologies, Robert H. Hartz

Theses and Dissertations

In dynamic data environments, the large volume of transactions requires flexible control structures to effectively balance the flow of information between producers and consumers. Information dissemination-based systems, using both data push and pull delivery mechanisms, provide a possible scalable solution for data-intensive applications. In this research, a methodology is proposed to capture information dissemination design features in the form of active database rules to effectively control dynamic data applications. As part of this design methodology, information distribution properties are analyzed, data dissemination mechanisms are transformed into an active rule framework, and the desired reactive behavior is achieved through rule customization. …

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Transforming Aggregate Object-Oriented Formal Specifications To Code, John A. Kissack Mar 1999

Transforming Aggregate Object-Oriented Formal Specifications To Code, John A. Kissack

Theses and Dissertations

The feasibility of a transformational formal-based software engineering tool has been the focus of AFIT research for several years. Until now, the main research emphasis has been placed on the individual components that would comprise such a transformational system; therefore, this research demonstrates how a representative collection of aggregate objects would be transformed from specification to code. The research focused on critical integration issues associated with a formal-based software transformation system, such as the source specification, the problem space architecture, design architecture, design transforms, and target software transforms. Software is critical in today's Air Force, yet its specification, design, and …

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Transforming Cobol Legacy Software To A Generic Imperative Model, Dina L. Moraes Mar 1999

Transforming Cobol Legacy Software To A Generic Imperative Model, Dina L. Moraes

Theses and Dissertations

Legacy COBOL code presents challenges for organizations wishing to increase their effectiveness and improve their efficiency. The systems that utilize this code are vital to enterprise operations, yet maintenance of code is expensive. This research presents an alternative that overcomes some of the problems of legacy COBOL code through the use of software reengineering techniques. This research develops a transformation system to convert COBOL code into a generic imperative model, recapturing the initial design and deciphering the requirements implemented by the legacy code, thereby making possible the documentation of legacy systems, design restructuring, and the re-design of a new, enhanced …

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Generating Executable Code From Formal Specifications Of Primitive Objects, Travis W. Tankersley Mar 1999

Generating Executable Code From Formal Specifications Of Primitive Objects, Travis W. Tankersley

Theses and Dissertations

The concept of developing a model for producing compilable and executable code from formal software specifications has long been a goal of software engineers. Previous research at the Air Force Institute of Technology (AFIT) has been focused on specification and domain analysis. An analysis model is populated using specifications written in Z. Then, a set of preliminary design transforms refines the specification in the analysis model. This research bridges the gap between analysis and design, allowing source code to be produced from formal specifications of primitive objects using transformational programming. The contribution of this thesis is to transform the analysis …

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Trade-Off Analysis Of Communications Capabilities Of Inter-Satellite Links, Andrew J. Feltman Mar 1999

Trade-Off Analysis Of Communications Capabilities Of Inter-Satellite Links, Andrew J. Feltman

Theses and Dissertations

This thesis designs, develops, and uses software Graphical User Interfaces (GUIs) to analyze the communications capabilities of Radio Frequency (RF) Inter-Satellite Links (ISLs). The GUIs are geared towards analyzing the proposed ISLs of the Discoverer II program, but are general enough to permit analysis of any free-space RF ISLs. Discoverer II is a demonstration program of low-earth orbiting satellites and is primarily focused on satellite-based sensor technology. This thesis shows RF ISLs can meet the program requirement to broadcast the sensor data back to CONUS in near-real-time. The GUIs operate in real-time and explore trade-offs in the communications capability by …

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Structural Emergence And The Collaborative Behavior Of Autonomous Nano-Satellites, Daniel J. Petrovich Mar 1999

Structural Emergence And The Collaborative Behavior Of Autonomous Nano-Satellites, Daniel J. Petrovich

Theses and Dissertations

The collaborative behavior of nano-satellites in a zero-gravity environment is explored, and satellite characteristics are proposed that maximize constellation robustness and minimize manufacturing costs. Behavioral algorithms are proposed to facilitate both swarming and structural formation and are validated using the Structural Emergence Simulator (STEMS) Graphical User Interface (GUl). A payload of multiple satellites is placed in a zero-gravity environment and released to re-configure autonomously into a pre-designed structure. Data transmission between satellites is not permitted during the swarming phase of the structure formation mission. A binary behavior algorithm is invented that produces a direction and magnitude solution to the satellite …

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Gps Signal Offset Detection And Noise Strength Estimation In A Parallel Kalman Filter Algorithm, Barry J. Vanek Mar 1999

Gps Signal Offset Detection And Noise Strength Estimation In A Parallel Kalman Filter Algorithm, Barry J. Vanek

Theses and Dissertations

Measurements from Global Positioning System (GPS) satellites are subject to corruption by signal interference and induced offsets. This thesis presents two independent algorithms to ensure the navigation system remains uncorrupted by these possible GPS failures. The first is a parameter estimation algorithm that estimates the measurement noise variance of each satellite. A redundant measurement differencing (RMD) technique provides direct observability of the differenced white measurement noise samples. The variance of the noise process is estimated and provided to the second algorithm, a parallel Kalman filter structure, which then adapts to changes in the real-world measurement noise strength. The parallel Kalman …

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