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Combat Identification Modeling Using Neural Network Techniques, Changwook Lim
Combat Identification Modeling Using Neural Network Techniques, Changwook Lim
Theses and Dissertations
The purposes of this research were: (1) validating Kim’s (2007) simulation method by applying analytic methods and (2) comparing the two different Robust Parameter Design methods with three measures of performance (label accuracy for enemy, friendly, and clutter). Considering the features of CID, input variables were defined as two controllable (threshold combination of detector and classifier) and three uncontrollable (map size, number of enemies and friendly). The first set of experiments considers Kim’s method using analytical methods. In order to create response variables, Kim’s method uses Monte Carlo simulation. The output results showed no difference between simulation and the analytic …
Numerical Analysis For Relevant Features In Intrusion Detection (Narfid), Jose Andres Gonzalez
Numerical Analysis For Relevant Features In Intrusion Detection (Narfid), Jose Andres Gonzalez
Theses and Dissertations
Identification of cyber attacks and network services is a robust field of study in the machine learning community. Less effort has been focused on understanding the domain space of real network data in identifying important features for cyber attack and network service classification. Motivations for such work allow for anomaly detection systems with less requirements on data “sniffed” off the network, extraction of features from the traffic, reduced learning time of algorithms, and ideally increased classification performance of anomalous behavior. This thesis evaluates the usefulness of a good feature subset for the general classification task of identifying cyber attacks and …
Using Predictive Rendering As A Vision-Aided Technique For Autonomous Aerial Refueling, Adam D. Weaver
Using Predictive Rendering As A Vision-Aided Technique For Autonomous Aerial Refueling, Adam D. Weaver
Theses and Dissertations
This research effort seeks to characterize a vision-aided approach for an Unmanned Aerial System (UAS) to autonomously determine relative position to another aircraft in a formation, specifically to address the autonomous aerial refueling problem. A system consisting of a monocular digital camera coupled with inertial sensors onboard the UAS is analyzed for feasibility of using this vision-aided approach. A three-dimensional rendering of the tanker aircraft is used to generate predicted images of the tanker as seen by the receiver aircraft. A rigorous error model is developed to model the relative dynamics between an INS-equipped receiver and the tanker aircraft. A …
Stochastic Estimation And Control Of Queues Within A Computer Network, Mingook Kim
Stochastic Estimation And Control Of Queues Within A Computer Network, Mingook Kim
Theses and Dissertations
Captain Nathan C. Stuckey implemented the idea of the stochastic estimation and control for network in OPNET simulator. He used extended Kalman filter to estimate packet size and packet arrival rate of network queue to regulate queue size. To validate stochastic theory, network estimator and controller is designed by OPNET model. These models validated the transient queue behavior in OPNET and work of Kalman filter by predicting the queue size and arrival rate. However, it was not enough to verify a theory by experiment. So, it needed to validate the stochastic control theory with other tools to get high validity. …
2008 Annual Report Of The Graduate School Of Engineering And Management, Air Force Institute Of Technology, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit
2008 Annual Report Of The Graduate School Of Engineering And Management, Air Force Institute Of Technology, Office Of Research And Sponsored Programs, Graduate School Of Engineering And Management, Afit
AFIT Documents
The Graduate School's Annual Report highlights research focus areas, new academic programs, faculty accomplishments and news, and provides top-level sponsor-funded research data and information.
An Analysis Of Construction Contractor Performance Evaluation System, Rebecca S. Brown
An Analysis Of Construction Contractor Performance Evaluation System, Rebecca S. Brown
Theses and Dissertations
A rigorous system for rating construction contractor performance does not exist for the USAF as identified by the Air Force Civil Engineer (USAF CE), Major General Del Eulberg (Eulberg, 2007). The United States Army Corp of Engineers (USACE) uses DD Form 2626 for contractor performance evaluation and contractor selection. The objective of this research is to strengthen the USAF contractor rating system by exploring USACE‘s use of DD Form 2626. Using data from DD Form 2626, statistical analysis was conducted to determine if the measured performance sub-items reflect their respective performance elements, whether the resulting performance elements relate to the …
Modernizing A Preventive Maintenance Strategy For Facility And Infrastructure Maintenance, Ross E. Dotzlaf
Modernizing A Preventive Maintenance Strategy For Facility And Infrastructure Maintenance, Ross E. Dotzlaf
Theses and Dissertations
Preventive maintenance (PM) is defined as regularly scheduled maintenance actions based on average failure rates. A properly implemented PM strategy can provide many benefits to an organization in terms of extending equipment life, optimizing resource expenditures, and balancing work schedules. Periodic evaluation of a PM strategy can help identify ways to improve efficiencies and maximize effectiveness. This research effort was accomplished by performing a case study of the United States Air Force’s infrastructure and facility PM program known as the Recurring Work Program (RWP). The methodology consisted of two phases. The first phase, intended to develop an understanding of the …
Ohio River Denial As A Transportation Corridor And Its Economic Impacts On The Energy Industry, Caglar Utku Guler
Ohio River Denial As A Transportation Corridor And Its Economic Impacts On The Energy Industry, Caglar Utku Guler
Theses and Dissertations
What if the Ohio River is disrupted or denied partially or completely as a transportation corridor? A disruption may be either a natural or man-made disaster or a planned outage on the river’s lock and dam structures. Recent history is full of water transport disruption events having significant economic effects on the waterside industries. To assess coal-based economic impacts, we developed a network flow model to represent waterside coal-fired power plants situated along the Ohio River, their respective coal supplying mines, and the various transportation modes that connect them. We show that significant transportation-centric insights can be derived by using …
Network Security Using Self Organized Multi-Agent Swarms, Eric M. Holloway, Gary B. Lamont, Gilbert L. Peterson
Network Security Using Self Organized Multi-Agent Swarms, Eric M. Holloway, Gary B. Lamont, Gilbert L. Peterson
Faculty Publications
Computer network cyber-security is a very serious concern in many commercial, industrial, and military environments. This paper proposes a new computer network security approach defined by self organized agent swarms (SOMAS) which provides a novel computer network security management framework based upon desired overall system behaviors. The SOMAS structure evolves based upon the partially observable Markov decision process (POMDP) formal model and the more complex interactive-POMDP and decentralized-POMDP models. Example swarm specific and network based behaviors are formalized and simulated. This paper illustrates through various statistical testing techniques, the significance of this proposed SOMAS architecture.
Evaluation Of Performance Of A Maximum Likelihood Estimator For Tracking Purposes In The Presence Of Speckle Noise, Adrian Brett Monz
Evaluation Of Performance Of A Maximum Likelihood Estimator For Tracking Purposes In The Presence Of Speckle Noise, Adrian Brett Monz
Theses and Dissertations
In many cases, optical tracking systems do not have cooperative beacons avail- able. This is particularly true for the case involving tracking a laser illuminated target such as a missile seeker head, where the object of interest is an extended source. Furthermore the extended source is often observed in the presence of noise such as shot and speckle noise as well as atmospheric turbulence which further degrades the signal. This research effort presents the evaluation of an existing algorithm based on the maximum-likelihood technique for tilt estimation in the presence of extended sources and speckle noise, with particular application to …
Satellite-Based Fusion Of Image/Inertial Sensors For Precise Geolocation, Neil R. Jesse
Satellite-Based Fusion Of Image/Inertial Sensors For Precise Geolocation, Neil R. Jesse
Theses and Dissertations
The ability to produce high-resolution images of the Earth’s surface from space has flourished in recent years with the continuous development and improvement of satellite-based imaging sensors. Earth-imaging satellites often rely on complex onboard navigation systems, with dependence on Global Positioning System (GPS) tracking and/or continuous post-capture georegistration, to accurately geolocate ground targets of interest to either commercial and military customers. Consequently, these satellite systems are often massive, expensive, and susceptible to poor or unavailable target tracking capabilities in GPS-denied environments. Previous research has demonstrated that a tightly-coupled image-aided inertial navigation system (INS), using existing onboard imaging sensors, can provide …
Communication Free Robot Swarming, Zachary C. Gray
Communication Free Robot Swarming, Zachary C. Gray
Theses and Dissertations
As the military use of unmanned aerial vehicles increases, a growing need for novel strategies to control these systems exists. One such method for controlling many unmanned aerial vehicles simultaneously is the through the use of swarm algorithms. This research explores a swarm robotic algorithm developed by Kadrovach implemented on Pioneer Robots in a real-world environment. An adaptation of his visual sensor is implemented using stereo vision as the primary method of sensing the environment. The swarm members are prohibited from explicitly communicating other than passively through the environment. The resulting implementation produces a communication free swarming algorithm. The algorithm …
Chip To Chip Optical Interconnection Using Mems Mirrors, Tod V. Laurvick
Chip To Chip Optical Interconnection Using Mems Mirrors, Tod V. Laurvick
Theses and Dissertations
This experiment explores the use of MEMS mirrors to direct subsurface optical signals to another device and reception of those signals for use in chip to chip communications. Devices were built in PolyMUMPs to control horizontal and vertical beam direction and tilting in the outgoing signal and MEMS beam splitters for the incoming signal. Several elements of the outgoing beam path were successful and those which needed improvement indicate a high probability of success with limited trials needed and currently successful design elements could still be improved within the scope of PolyMUMPs. The incoming beam path elements were not successful …
Automated Virtual Machine Introspection For Host-Based Intrusion Detection, Brett A. Pagel
Automated Virtual Machine Introspection For Host-Based Intrusion Detection, Brett A. Pagel
Theses and Dissertations
This thesis examines techniques to automate configuration of an intrusion detection system utilizing hardware-assisted virtualization. These techniques are used to detect the version of a running guest operating system, automatically configure version-specific operating system information needed by the introspection library, and to locate and monitor important operating system data structures. This research simplifies introspection library configuration and is a step toward operating system independent introspection. An operating system detection algorithm and Windows virtual machine system service dispatch table monitor are implemented using the Xen hypervisor and a modified version of the XenAccess library. All detection and monitoring is implemented from …
Adaptive Control Of Woofer-Tweeter Adaptive Optics, Jimmie J. Perez
Adaptive Control Of Woofer-Tweeter Adaptive Optics, Jimmie J. Perez
Theses and Dissertations
Adaptive optics applies advanced sensing and control to improve the ability of optical systems to collect images through a turbulent atmosphere. The results of this research effort demonstrate that the combination of two recent approaches improves the performance of adaptive optics in directed energy and laser communication scenarios. The first approach is adaptive control, which offers improved performance over fixed-gain controllers in the presence of rapidly changing turbulence. The second approach incorporated into the study is a dual-mirror system. The two mirrors are a high-bandwidth, low-actuator-stroke (tweeter) mirror and a low-bandwidth, large actuator-stroke (woofer) mirror. The woofer-tweeter combination allows for …
Automated Knowledge Generation With Persistent Surveillance Video, Daniel T. Schmitt
Automated Knowledge Generation With Persistent Surveillance Video, Daniel T. Schmitt
Theses and Dissertations
The Air Force has increasingly invested in persistent surveillance platforms gathering a large amount of surveillance video. Ordinarily, intelligence analysts watch the video to determine if suspicious activities are occurring. This approach to video analysis can be a very time and manpower intensive process. Instead, this thesis proposes that by using tracks generated from persistent video, we can build a model to detect events for an intelligence analyst. The event that we chose to detect was a suspicious surveillance activity known as a casing event. To test our model we used Global Positioning System (GPS) tracks generated from vehicles driving …
Subjective Audio Quality Over A Secure Ieee 802.11n Draft 2.0 Wireless Local Area Network, Benjamin W. Ramsey
Subjective Audio Quality Over A Secure Ieee 802.11n Draft 2.0 Wireless Local Area Network, Benjamin W. Ramsey
Theses and Dissertations
This thesis investigates the quality of audio generated by a G.711 codec and transmission over an IEEE 802.11n draft 2.0 wireless local area network (WLAN). Decline in audio quality due to additional calls or by securing the WLAN with transport mode Internet Protocol Security (IPsec) is quantified. Audio quality over an IEEE 802.11n draft 2.0 WLAN is also compared to that of IEEE 802.11b and IEEE 802.11g WLANs under the same conditions. Audio quality is evaluated by following International Telecommunication Union Telecommunication Standardization Sector (ITU-T) Recommendation P.800, where human subjects rate audio clips recorded during various WLAN configurations. The Mean …
An Fpga-Based System For Tracking Digital Information Transmitted Via Peer-To-Peer Protocols, Karl R. Schrader
An Fpga-Based System For Tracking Digital Information Transmitted Via Peer-To-Peer Protocols, Karl R. Schrader
Theses and Dissertations
This thesis addresses the problem of identifying and tracking digital information that is shared using peer-to-peer file transfer and Voice over IP (VoIP) protocols. The goal of the research is to develop a system for detecting and tracking the illicit dissemination of sensitive government information using file sharing applications within a target network, and tracking terrorist cells or criminal organizations that are covertly communicating using VoIP applications. A digital forensic tool is developed using an FPGA-based embedded software application. The tool is designed to process file transfers using the BitTorrent peer-to-peer protocol and VoIP phone calls made using the Session …
Graduate School Academic Catalog 2009-2010, Graduate School Of Engineering And Management, Air Force Institute Of Technology
Graduate School Academic Catalog 2009-2010, Graduate School Of Engineering And Management, Air Force Institute Of Technology
AFIT Documents
The Graduate Catalog represents the offerings, programs, and requirements in effect at the time of publication.
Cyber Power In The 21st Century, Joseph M. Elbaum
Cyber Power In The 21st Century, Joseph M. Elbaum
Theses and Dissertations
Historically, the United States Congress has acknowledged that a separate branch of military service is required to exert supremacy over each of the recognized Domains of Operation. Throughout the evolution of modern warfare, leading minds in military theory have come to the conclusion that due to fundamental differences inherent in the theory and tactics that must be employed in order to successfully wage war within a domain’s associated environment, a specialized force was needed - until now. With the recent inclusion of Cyberspace as an operational domain by the Department of Defense, the case should be made that it, too, …
Integrated Approach To Airborne Laser Communication, James A. Louthain
Integrated Approach To Airborne Laser Communication, James A. Louthain
Theses and Dissertations
Lasers offer tremendous advantages over RF communication systems in bandwidth and security, due to their ultra-high frequency and narrow spatial beamwidth. Atmospheric turbulence causes severe received power variations and high bit error rates (BERs) in airborne laser communication. Airborne optical communication systems require special considerations in size, complexity, power, and weight. Conventional adaptive optics systems correct for the phase only and cannot correct for strong scintillation, but here the two transmission paths are separated sufficiently so that the strong scintillation is \averaged out" by incoherently summing up the two beams in the receiver. This requisite separation distance is derived for …
Sub-Circuit Selection And Replacement Algorithms Modeled As Term Rewriting Systems, Eric D. Simonaire
Sub-Circuit Selection And Replacement Algorithms Modeled As Term Rewriting Systems, Eric D. Simonaire
Theses and Dissertations
Intent protection is a model of software obfuscation which, among other criteria, prevents an adversary from understanding the program’s function for use with contextual information. Relating this framework for obfuscation to malware detection, if a malware detector can perfectly normalize a program P and any obfuscation (variant) of the program O(P), the program is not intent protected. The problem of intent protection on programs can also be modeled as intent protection on combinational logic circuits. If a malware detector can perfectly normalize a circuit C and any obfuscation (variant) O(C) of the circuit, the circuit is not intent protected. In …
Secureqemu: Emulation-Based Software Protection Providing Encrypted Code Execution And Page Granularity Code Signing, William B. Kimball
Secureqemu: Emulation-Based Software Protection Providing Encrypted Code Execution And Page Granularity Code Signing, William B. Kimball
Theses and Dissertations
This research presents an original emulation-based software protection scheme providing protection from reverse code engineering (RCE) and software exploitation using encrypted code execution and page-granularity code signing, respectively. Protection mechanisms execute in trusted emulators while remaining out-of-band of untrusted systems being emulated. This protection scheme is called SecureQEMU and is based on a modified version of Quick Emulator (QEMU) [5]. RCE is a process that uncovers the internal workings of a program. It is used during vulnerability and intellectual property (IP) discovery. To protect from RCE program code may have anti-disassembly, anti-debugging, and obfuscation techniques incorporated. These techniques slow the …
Nondestructive Evaluation Of Aircraft Composites Using Terahertz Time Domain Spectroscopy, Christopher D. Stoik
Nondestructive Evaluation Of Aircraft Composites Using Terahertz Time Domain Spectroscopy, Christopher D. Stoik
Theses and Dissertations
Terahertz (THz) time domain spectroscopy (TDS) was assessed as a nondestructive evaluation technique for aircraft composites. Material properties of glass fiber composite were measured using both transmission and reflection configuration. The interaction of THz with a glass fiber composite was then analyzed, including the effects of scattering, absorption, and the index of refraction, as well as effective medium approximations. THz TDS, in both transmission and reflection configuration, was used to study composite damage, including voids, delaminations, mechanical damage, and heat damage. Measurement of the material properties on samples with localized heat damage showed that burning did not change the refractive …
Maximizing Warfighter Capability Using Surveyed Necessity Measurement: Application To The Usaf F-15c Fleet, John M. Colombi, David R. Jacques, Dennis D. Strouble
Maximizing Warfighter Capability Using Surveyed Necessity Measurement: Application To The Usaf F-15c Fleet, John M. Colombi, David R. Jacques, Dennis D. Strouble
Faculty Publications
Within the Department of Defense, with changing missions to counter dynamic and asymmetrical threats, the acquisition workforce strives to maximize capability for joint warfighting. How acquisition professionals measure and select capability improvements for the nation’s weapon systems is a perpetual challenge, made even more complex with constrained defense budgets. This study identifies a method for determining which upgrades should be purchased (production) for which aircraft in the F- 15C fleet by optimizing a capability proxy measure. Each upgrade’s “necessity” for a given mission area was obtained by conducting a survey of over 250 experienced F-15C pilots. The solution presented in …
Limitations Of A True Random Number Generator In A Field Programmable Gate Array, Jennifer L. Brady
Limitations Of A True Random Number Generator In A Field Programmable Gate Array, Jennifer L. Brady
Theses and Dissertations
Random number generators are used in many areas of engineering, computer science, most notably in simulations and cryptographic applications. There are true random number generators (TRNG) and pseudo random number generators (PRNG). Only a true random number generator is secure because the output bits are non-repeating and nonreproducible. As society has become more dependent on electronic technology the need for true random number generators has increased due to processes that require encryption in everyday use. A fast true random number generator on a field programmable gate array presents digital designers with the ability to have the generator on chip. Since …
Extension Of Viscoplasticity Based On Overstress To Capture The Effects Of Prior Aging On The Time Dependent Deformation Behavior Of A High-Temperature Polymer: Experiments And Modeling, Amber J. W. Mcclung
Extension Of Viscoplasticity Based On Overstress To Capture The Effects Of Prior Aging On The Time Dependent Deformation Behavior Of A High-Temperature Polymer: Experiments And Modeling, Amber J. W. Mcclung
Theses and Dissertations
The inelastic deformation behavior of PMR-15 neat resin, a high-temperature thermoset polymer, was investigated at 288 degrees C. The experimental program was designed to explore the influence of strain rate on tensile loading, unloading, and strain recovery behaviors. In addition, the effect of the prior strain rate on the relaxation response of the material, as well as on the creep behavior following strain controlled loading were examined. The experimental data were modeled with the Viscoplasticity Based on Overstress (VBO) theory. A systematic procedure for determining model parameters was developed and the model was employed to predict the response of the …
Application Of Optimization Techniques To Spectrally Modulated, Spectrally Encoded Waveform Design, Todd W. Beard
Application Of Optimization Techniques To Spectrally Modulated, Spectrally Encoded Waveform Design, Todd W. Beard
Theses and Dissertations
A design process is demonstrated for a coexistent scenario containing Spectrally Modulated, Spectrally Encoded (SMSE) and Direct Sequence Spread Spectrum (DSSS) signals. Coexistent SMSE-DSSS designs are addressed under both perfect and imperfect DSSS code tracking conditions using a non-coherent delay-lock loop (DLL). Under both conditions, the number of SMSE subcarriers and subcarrier spacing are the optimization variables of interest. For perfect DLL code tracking conditions, the GA and RSM optimization processes are considered independently with the objective function being end-to-end DSSS bit error rate. A hybrid GA-RSM optimization process is used under more realistic imperfect DLL code tracking conditions. In …
A Novel Method Characterizing The Impact Response Of Functionally Graded Plates, Reid A. Larson
A Novel Method Characterizing The Impact Response Of Functionally Graded Plates, Reid A. Larson
Theses and Dissertations
Functionally graded material (FGM) plates are advanced composites with properties that vary continuously through the thickness of the plate. Metal-ceramic FGM plates have been proposed for use in thermal protection systems where a metal-rich interior surface of the plate gradually transitions to a ceramic-rich exterior surface of the plate. The ability of FGMs to resist impact loads must be demonstrated before using them in high-temperature environments in service. This dissertation presents a novel technique by which the impact response of FGM plates is characterized for low-velocity, low- to medium-energy impact loads. An experiment was designed where strain histories in FGM …
Closed-Loop Adaptive Optics Control In Strong Atmospheric Turbulence, Todd M. Venema
Closed-Loop Adaptive Optics Control In Strong Atmospheric Turbulence, Todd M. Venema
Theses and Dissertations
A self-referencing interferometer based closed-loop adaptive optics controller is developed which is designed to operate effectively under strong turbulence conditions. The aberrated optical field is modeled stochastically and then estimates of the state of the system are developed using a steady-state, fixed-gain Kalman filter. The phase of the optical field is considered the state of the system which is wrapped in a limited range of (-π, π]. This phase is unwrapped through the use of a least-squares reconstructor which has been modified to work effectively in the presence of branch points associated with strong turbulence. The conjugate of the optical …