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Computer Sciences

2004

Air Force Institute of Technology

Articles 1 - 26 of 26

Full-Text Articles in Physical Sciences and Mathematics

Forensic Analysis Of Digital Image Tampering, Jonathan R. Sturak Dec 2004

Forensic Analysis Of Digital Image Tampering, Jonathan R. Sturak

Theses and Dissertations

The use of digital photography has increased over the past few years, a trend which opens the door for new and creative ways to forge images. The manipulation of images through forgery influences the perception an observer has of the depicted scene, potentially resulting in ill consequences if created with malicious intentions. This poses a need to verify the authenticity of images originating from unknown sources in absence of any prior digital watermarking or authentication technique. This research explores the holes left by existing research; specifically, the ability to detect image forgeries created using multiple image sources and specialized methods …

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Pattern Search Ranking And Selection Algorithms For Mixed-Variable Optimization Of Stochastic Systems, Todd A. Sriver Sep 2004

Pattern Search Ranking And Selection Algorithms For Mixed-Variable Optimization Of Stochastic Systems, Todd A. Sriver

Theses and Dissertations

A new class of algorithms is introduced and analyzed for bound and linearly constrained optimization problems with stochastic objective functions and a mixture of design variable types. The generalized pattern search (GPS) class of algorithms is extended to a new problem setting in which objective function evaluations require sampling from a model of a stochastic system. The approach combines GPS with ranking and selection (R&S) statistical procedures to select new iterates. The derivative-free algorithms require only black-box simulation responses and are applicable over domains with mixed variables (continuous, discrete numeric, and discrete categorical) to include bound and linear constraints on …

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Visual Unified Modeling Language For The Composition Of Scenarios In Modeling And Simulation Systems, Daniel E. Swayne Sep 2004

Visual Unified Modeling Language For The Composition Of Scenarios In Modeling And Simulation Systems, Daniel E. Swayne

Theses and Dissertations

The Department of Defense uses modeling and simulation systems in many various roles, from research and training to modeling likely outcomes of command decisions. Simulation systems have been increasing in complexity with the increased capability of low-cost computer systems to support these DOD requirements. The demand for scenarios is also increasing, but the complexity of the simulation systems has caused a bottleneck in scenario development due to the limited number of individuals with knowledge of the arcane simulator languages in which these scenarios are written. This research combines the results of previous AFIT efforts in visual modeling languages to create …

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Improving Tcp Performance By Estimating Errors In A Long Delay, High Error Rate Environment, Stephanie E. Carroll Jul 2004

Improving Tcp Performance By Estimating Errors In A Long Delay, High Error Rate Environment, Stephanie E. Carroll

Theses and Dissertations

Interest in finding methods of improving TCP performance over satellite and wireless networks is high. This has been an active area of research within the networking community. This research develops an algorithm, CETEN-R for TCP to determine if a particular packet is lost due to congestion or corruption and react accordingly. An analysis of the performance of CETEN-R under a variety of conditions is studied and then compared to TCP Reno and TCP New Reno. When delay is high and the error rate is high CETEN-R showed a 77.5% increase in goodput over TCP New Reno and a 33.8% increase …

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Cognitive Robot Mapping With Polylines And An Absolute Space Representation, Kennard R. Laviers, Gilbert L. Peterson Apr 2004

Cognitive Robot Mapping With Polylines And An Absolute Space Representation, Kennard R. Laviers, Gilbert L. Peterson

Faculty Publications

Robot mapping even today is one of the most challenging problems in robot programming. Most successful methods use some form of occupancy grid to represent a mapped region. This approach becomes problematic if the robot is mapping a large environment, the map quickly becomes too large for processing and storage. Rather than storing the map as an occupancy grid, our robot (equipped with sonars) sees the world as a series of connected spaces. These spaces are initially mapped as an occupancy grid in a room by room fashion. As the robot leaves a space, denoted by passing through a doorway, …

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The United States Marine Corps Data Collaboration Requirements: Retrieving And Integrating Data From Multiple Databases, Pamela J. Cole Mar 2004

The United States Marine Corps Data Collaboration Requirements: Retrieving And Integrating Data From Multiple Databases, Pamela J. Cole

Theses and Dissertations

The goal of this research is to develop an information sharing and database integration model and suggest a framework to fully satisfy the United States Marine Corps collaboration requirements as well as its information sharing and database integration needs. This research is exploratory; it focuses on only one initiative: the IT-21 initiative. The IT-21 initiative dictates The Technology for the United States Navy and Marine Corps, 2000-2035: Becoming a 21st Century Force. The IT-21 initiative states that Navy and Marine Corps information infrastructure will be based largely on commercial systems and services, and the Department of the Navy must ensure …

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An Exploratory Analysis Of Factors Affecting Participation In Air Force Knowledge Now Communities Of Practice, David C. Fitzgerald Mar 2004

An Exploratory Analysis Of Factors Affecting Participation In Air Force Knowledge Now Communities Of Practice, David C. Fitzgerald

Theses and Dissertations

As the AF continues to lose its knowledge base through retirements and downsizing, the need to get maximum use from the remaining knowledge base becomes increasingly important. In their efforts to help the Department of Defense and the Air Force Chief Information Officer (AFCIO) meet their knowledge management goals, Air Force Material Command (AFMC) has been working to implement the use of communities of practice. A primary goal of AFMC/DRW , the AF Knowledge Now program office, and the office of the AFCIO is to increase effectiveness and participation within communities of practice. The goal of this research is to …

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Evolution Of Control Programs For A Swarm Of Autonomous Unmanned Aerial Vehicles, Kevin M. Milam Mar 2004

Evolution Of Control Programs For A Swarm Of Autonomous Unmanned Aerial Vehicles, Kevin M. Milam

Theses and Dissertations

Unmanned aerial vehicles (UAVs) are rapidly becoming a critical military asset. In the future, advances in miniaturization are going to drive the development of insect size UAVs. New approaches to controlling these swarms are required. The goal of this research is to develop a controller to direct a swarm of UAVs in accomplishing a given mission. While previous efforts have largely been limited to a two-dimensional model, a three-dimensional model has been developed for this project. Models of UAV capabilities including sensors, actuators and communications are presented. Genetic programming uses the principles of Darwinian evolution to generate computer programs to …

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Development Approaches Coupled With Verification And Validation Methodologies For Agent-Based Mission-Level Analytical Combat Simulations, Lance E. Champagne Mar 2004

Development Approaches Coupled With Verification And Validation Methodologies For Agent-Based Mission-Level Analytical Combat Simulations, Lance E. Champagne

Theses and Dissertations

This research investigated the applicability of agent-based combat simulations to real-world combat operations. An agent-based simulation of the Allied offensive search for German U-Boats in the Bay of Biscay during World War II was constructed, extending the state-of-the-art in agent-based combat simulations, bridging the gap between the current level of agent-like combat simulations and the concept of agent-based simulations found in the broader literature. The proposed simulation advances agent-based combat simulations to “validateable” mission-level military operations. Simulation validation is a complex task with numerous, diverse techniques available and levels of validation differing significantly among simulations and applications. This research presents …

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An Exploration Of Cultural Factors Affecting Use Of Communities Of Practice, Peter L. Hinrichsen Mar 2004

An Exploration Of Cultural Factors Affecting Use Of Communities Of Practice, Peter L. Hinrichsen

Theses and Dissertations

On-line communities of practice are potentially powerful social learning networks that can improve organizational performance. Unfortunately, administrators of on-line communities of practice report that community members do not take full advantage of this potential. This study used Shaw and Tuggle's (2003) factors of knowledge management (KM) culture affecting organizational acceptance of a knowledge management initiative to explore this issue. It was hypothesized that respondents whose communities of practice possessed higher average community use per member would rate KM culture variables higher than respondents whose communities possessed a lower average community use. An analysis of survey data collected from Air Force …

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Exploring Content Management Issues In Air Force On-Line Communities Of Practice: A Multiple Case Study Approach, Jaime A. Rodriguez Mar 2004

Exploring Content Management Issues In Air Force On-Line Communities Of Practice: A Multiple Case Study Approach, Jaime A. Rodriguez

Theses and Dissertations

The practice of content management attempts regardless of platform to ensure that pertinent information is current, relevant, and presented in a usable manner. The Air Force Communities of Practice (CoPs) are hosted by AFMC/DRW, The purpose of these CoPs is to facilitate and promote an environment of capturing and sharing knowledge among members of a particular field task or common practice. As the host for these CoPs AFMC/DRW desires to increase CoP participation efficiency and effectiveness. Addressing existing or potential content management issues will help do so. This multiple-case study research observed and interviewed managers and members of eight active …

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Automating Security Protocol Analysis, Stephen W. Mancini Mar 2004

Automating Security Protocol Analysis, Stephen W. Mancini

Theses and Dissertations

When Roger Needham and Michael Schroeder first introduced a seemingly secure protocol 24, it took over 18 years to discover that even with the most secure encryption, the conversations using this protocol were still subject to penetration. To date, there is still no one protocol that is accepted for universal use. Because of this, analysis of the protocol outside the encryption is becoming more important. Recent work by Joshua Guttman and others 9 have identified several properties that good protocols often exhibit. Termed Authentication Tests, these properties have been very useful in examining protocols. The purpose of this research is …

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Agent Based Simulation Seas Evaluation Of Dodaf Architecture, Gregory V. Destefano Mar 2004

Agent Based Simulation Seas Evaluation Of Dodaf Architecture, Gregory V. Destefano

Theses and Dissertations

With Department of Defense (DoD) weapon systems being deeply rooted in the command, control, communications, computers, intelligence, surveillance, and reconnaissance (C4ISR) structure, it is necessary for combat models to capture C4ISR effects in order to properly assess military worth. Unlike many DoD legacy combat models, the agent based model System Effectiveness and Analysis Simulation (SEAS) is identified as having C4ISR analysis capabilities. In lieu of requirements for all new DoD C4ISR weapon systems to be placed within a DoD Architectural Framework (DoDAF), investigation of means to export data from the Framework to the combat model SEAS began. Through operational, system, …

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Machine Learning Techniques For Characterizing Ieee 802.11b Encrypted Data Streams, Michael J. Henson Mar 2004

Machine Learning Techniques For Characterizing Ieee 802.11b Encrypted Data Streams, Michael J. Henson

Theses and Dissertations

As wireless networks become an increasingly common part of the infrastructure in industrialized nations, the vulnerabilities of this technology need to be evaluated. Even though there have been major advancements in encryption technology, security protocols and packet header obfuscation techniques, other distinguishing characteristics do exist in wireless network traffic. These characteristics include packet size, signal strength, channel utilization and others. Using these characteristics, windows of size 11, 31, and 51 packets are collected and machine learning (ML) techniques are trained to classify applications accessing the 802.11b wireless channel. The four applications used for this study included E-Mail, FTP, HTTP, and …

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Investigation Of Geobase Implementation Issues: Case Study Of Information Resource Management, Mario L. Oliver Mar 2004

Investigation Of Geobase Implementation Issues: Case Study Of Information Resource Management, Mario L. Oliver

Theses and Dissertations

Billions of dollars have been wasted on failed information system (IS) projects over the last decade in the private and public sectors. More specifically, the tri-service environment of the U.S. military has not implemented a single successful geospatial IS (GIS). The lack of a service-wide insertion process for GIS was cited as the most significant cause for military GIS failures. GeoBase represents the USAF's most recent GIS implementation. The GeoBase program focuses on Information Resource Management (IRM) and cultural issues. The GeoBase Sustainment Model (GSM), anecdotally developed by GeoBase leadership to reflect implementation issues and the IRM practices of the …

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Throughput Performance Evaluation And Analysis Of Unmodified Bluetooth Devices, Steven J. Taylor Mar 2004

Throughput Performance Evaluation And Analysis Of Unmodified Bluetooth Devices, Steven J. Taylor

Theses and Dissertations

The Air Force relies on the application of new technologies to support and execute its mission. As new technologies develop, the integration of that technology is studied to determine the costs and benefits it may provide to the war fighter. One such emergent technology is the Bluetooth wireless protocol, used to connect a small number of devices over a short distance. The short distance is a feature that makes using the protocol desirable. However short, there is still a vulnerability to interception. This research identifies ranges at which several commercially available Bluetooth devices are usable. Various combinations of both distance …

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Swarm Based Implementation Of A Virtual Distributed Database System In A Sensor Network, Wen C. Lee Mar 2004

Swarm Based Implementation Of A Virtual Distributed Database System In A Sensor Network, Wen C. Lee

Theses and Dissertations

The deployment of unmanned aerial vehicles (UAVs) in recent military operations has had success in carrying out surveillance and combat missions in sensitive areas. An area of intense research on UAVs has been on controlling a group of small-sized UAVs to carry out reconnaissance missions normally undertaken by large UAVs such as Predator or Global Hawk. A control strategy for coordinating the UAV movements of such a group of UAVs adopts the bio-inspired swarm model to produce autonomous group behavior. This research proposes establishing a distributed database system on a group of swarming UAVs, providing for data storage during a …

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Software Development Outsourcing Decision Support Tool With Neural Network Learning, James D. Newberry Mar 2004

Software Development Outsourcing Decision Support Tool With Neural Network Learning, James D. Newberry

Theses and Dissertations

The Air Force (AF) needs an evolving software tool for guiding decision makers through the complexities of software outsourcing. Previous research identified specific outsourcing strategies and linked them to goals and consequences through a variety of relationship rules. These strategies and relationship rules were inserted into a decision support tool. Since that time, more historical data and outsourcing literature has been collected thus necessitating an update to such a tool. As the number of software outsourcing projects are completed, the AF must capture the outsourcing decision experiences which guided the projects and their outcomes. In order to efficiently incorporate this …

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Netwars Based Study Of A Joint Stars Link-16 Network, Charlie I. Cruz Mar 2004

Netwars Based Study Of A Joint Stars Link-16 Network, Charlie I. Cruz

Theses and Dissertations

Both secure and anti-jam resistant, the Link-16 is the primary communications channel used by the Joint Surveillance Target Attack Radar System (Joint STARS) for the exchange of real-time tactical data among various ground, air, and sea platforms of the United States of America and North Atlantic Treaty Organization forces. This research explored the effect of increasing network traffic for imagery transfer to the mean delay when operating under different network topologies. Using Network Warfare Simulation (NETWARS), three different missions were simulated to run on five network topologies having a different number of participants, different assigned time slots, and stacked nets. …

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Comparative Analysis Of Active And Passive Mapping Techniques In An Internet-Based Local Area Network, James B. Kuntzelman Mar 2004

Comparative Analysis Of Active And Passive Mapping Techniques In An Internet-Based Local Area Network, James B. Kuntzelman

Theses and Dissertations

Network mapping technologies allow quick and easy discovery of computer systems throughout a network. Active mapping methods, such as using nmap, capitalize on the standard stimulus-response of network systems to probe target systems. In doing so, they create extra traffic on the network, both for the initial probe and for the target system's response. Passive mapping methods work opportunistically, listening for network traffic as it transits the system. As such, passive methods generate minimal network traffic overhead. Active methods are still standard methods for network information gathering; passive techniques are not normally used due to the possibility of missing important …

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An Analysis Of The Performance And Security Of J2sdk 1.4 Jsse Implementation Of Ssl/Tls, Danny R. Bias Mar 2004

An Analysis Of The Performance And Security Of J2sdk 1.4 Jsse Implementation Of Ssl/Tls, Danny R. Bias

Theses and Dissertations

The Java SSL/TLS package distributed with the J2SE 1.4.2 runtime is a Java implementation of the SSLv3 and TLSv1 protocols. Java-based web services and other systems deployed by the DoD will depend on this implementation to provide confidentiality, integrity, and authentication. Security and performance assessment of this implementation is critical given the proliferation of web services within DoD channels. This research assessed the performance of the J2SE 1.4.2 SSL and TLS implementations, paying particular attention to identifying performance limitations given a very secure configuration. The performance metrics of this research were CPU utilization, network bandwidth, memory, and maximum number of …

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Intelligent Query Answering Through Rule Learning And Generalization, James M. Carsten Mar 2004

Intelligent Query Answering Through Rule Learning And Generalization, James M. Carsten

Theses and Dissertations

The Department of Defense (DoD) relies heavily on information systems to complete a myriad of tasks, from day-to-day personnel actions to mission critical imagery retrieval, intelligence analysis, and mission planning. The astronomical growth in size and performance of data storage systems leads to problems in processing the amount of data returned on any given query. Typical relational database systems return a set of unordered records. This approach is acceptable in small information systems, but in large systems, such as military image retrieval systems with more than 1 million records, it requires considerable time (often hours to days) to sort through …

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Visual Debugging Of Object-Oriented Systems With The Unified Modeling Language, Wendell E. Fox Mar 2004

Visual Debugging Of Object-Oriented Systems With The Unified Modeling Language, Wendell E. Fox

Theses and Dissertations

The Department of Defense (DoD) is developing a Joint Battlespace Infosphere, linking a large number of data sources and user applications. Debugging and analysis tools are required to aid in this process. Debugging of large object-oriented systems is a difficult cognitive process that requires understanding of both the overall and detailed behavior of the application. In addition, many such applications linked through a distributed system add to this complexity. Standard debuggers do not utilize visualization techniques, focusing mainly on information extracted directly from the source code. To overcome this deficiency, this research designs and implements a methodology that enables developers …

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Concurrent Cognitive Mapping And Localization Using Expectation Maximization, Kennard R. Laviers Mar 2004

Concurrent Cognitive Mapping And Localization Using Expectation Maximization, Kennard R. Laviers

Theses and Dissertations

Robot mapping remains one of the most challenging problems in robot programming. Most successful methods use some form of occupancy grid for representing a mapped region. An occupancy grid is a two dimensional array in which the array cells represents (x,y) coordinates of a cartesian map. This approach becomes problematic in mapping large environments as the map quickly becomes too large for processing and storage. Rather than storing the map as an occupancy grid, our robot (equipped with ultrasonic sonars) views the world as a series of connected spaces. These spaces are initially mapped as an occupancy grid in a …

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Packet Analysis Of Unmodified Bluetooth Communication Devices, Neal A. Watts Mar 2004

Packet Analysis Of Unmodified Bluetooth Communication Devices, Neal A. Watts

Theses and Dissertations

Bluetooth technology has potential for widespread use within the Department of Defense and the Air Force. An office environment using Bluetooth technology can wirelessly connect computers, printers, and other office equipment in order to share information over short distances. The clutter and annoyance of cables connecting equipment can be eliminated. Bluetooth provides a standard interface for connection, as opposed to many different proprietary cables. The research is conducted indoors in a climate controlled environment, with minimal obstructions, to closely follow free-space signal propagation. Four different antenna orientations are used. The factors varied are the distance between devices, and the antenna …

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Automated Agent Ontology Creation For Distributed Databases, Austin A. Bartolo Mar 2004

Automated Agent Ontology Creation For Distributed Databases, Austin A. Bartolo

Theses and Dissertations

In distributed database environments, the combination of resources from multiple sources requiring different interfaces is a universal problem. The current solution requires an expert to generate an ontology, or mapping, which contains all interconnections between the various fields in the databases. This research proposes the application of software agents in automating the ontology creation for distributed database environments with minimal communication. The automatic creation of a domain ontology alleviates the need for experts to manually map one database to other databases in the environment. Using several combined comparison methods, these agents communicate and negotiate similarities between information sources and retain …

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