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Theses and Dissertations

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Articles 8191 - 8220 of 11510

Full-Text Articles in Engineering

Space Based Satellite Tracking And Characterization Utilizing Non-Imaging Passive Sensors, Bradley R. Townsend Mar 2008

Space Based Satellite Tracking And Characterization Utilizing Non-Imaging Passive Sensors, Bradley R. Townsend

Theses and Dissertations

A technique is developed to determine the orbit of a sunlight illuminated satellite passing through the field-of-view of a sensor platform in a Highly Elliptical Orbit (HEO) and Geosynchronous orbit (GEO). The technique develops two different methods of initial orbit determination. The first relies on the Gauss initial orbit determination method to develop an estimate of the state from angular data. The second method relies on positional data of the target relative to the Earth’s background to determine an estimate of the state. These estimates are then refined in a non-linear least squares routine. This estimate of the state is …

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Digital Signal Processing Leveraged For Intrusion Detection, Theodore J. Erickson Mar 2008

Digital Signal Processing Leveraged For Intrusion Detection, Theodore J. Erickson

Theses and Dissertations

This thesis describes the development and evaluation of a novel system called the Network Attack Characterization Tool (NACT). The NACT employs digital signal processing to detect network intrusions, by exploiting the Lomb-Scargle periodogram method to obtain a spectrum for sampled network traffic. The Lomb-Scargle method for generating a periodogram allows for the processing of unevenly sampled network data. This method for determining a periodogram has not yet been used for intrusion detection. The spectrum is examined to determine if features exist above a significance level chosen by the user. These features are considered an attack, triggering an alarm. Two traffic …

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Priority Based Buffering Over Multiple Lossy Links Using Tcp Aware Layer Buffering, Kevin J. Savidge Mar 2008

Priority Based Buffering Over Multiple Lossy Links Using Tcp Aware Layer Buffering, Kevin J. Savidge

Theses and Dissertations

Wireless military information systems require high reliability, which is difficult to achieve in adverse conditions. To provide high reliability, one must overcome packet loss across multiple wireless hops. Buffering packets in a lossy environment is well explored; however, the ability to selectively buffer TCP traffic across multiple lossy links is a new area of research. This document seeks to explore the delivery of high priority traffic in a lossy environment and conclude that prioritized buffing can increase the probability that a high priority download will finish, where others will fail. It is shown that buffering provides six times the throughput …

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Mission Impact Analysis Visualization For Enhanced Situational Awareness, Sean C. M. Carroll Mar 2008

Mission Impact Analysis Visualization For Enhanced Situational Awareness, Sean C. M. Carroll

Theses and Dissertations

This research effort examines the creation of mission impact analysis visualizations to enhance situational awareness. It focuses on using prefuse to create a visualization that allows the user to quickly understand the impact of the failure of any element needed directly or indirectly for a mission. The visualization correctly identifies the direct or indirect impact on physical requirements such as network links and servers as well as non-physical elements such as the generation of a report, or ability to perform a task. The visualization provides an overview of the situation, as well as including enhancements to allow for greater detail …

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Evaluating Security And Quality Of Service Considerations In Critical Infrastructure Communication Networks, Gregory R. Roberts Mar 2008

Evaluating Security And Quality Of Service Considerations In Critical Infrastructure Communication Networks, Gregory R. Roberts

Theses and Dissertations

This thesis demonstrates the benefits of utility communication based on Internet technology, some dangers in using Internet technology in establishing a utility intranet connecting protection and control systems, and compares three different approaches to making reservations for routing traffic in the utility intranet based on different levels of background traffic. A model of expected background traffic on a national utility intranet is presented. The Utility Communication Architecture 2.0 and the International Electrotechnical Commission (IEC) 61850 began laying the groundwork in 2002 in establishing an infrastructure allowing power substations, program logic controllers, remote terminal units, intelligent electronic devices, and other devices …

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Hot Swapping Protocol Implementations In The Opnet Modeler Development Environment, Mark E. Coyne Mar 2008

Hot Swapping Protocol Implementations In The Opnet Modeler Development Environment, Mark E. Coyne

Theses and Dissertations

This research effort demonstrates hot swapping protocol implementations in OPNET via the building of a dependency injection testing framework. The thesis demonstrates the externalization (compiling as stand-alone code) of OPNET process models, and their inclusion into custom DLL's (Dynamically Linked Libraries). A framework then utilizes these process model DLL's, to specify, or “inject,” process implementations post-compile time into an OPNET simulation. Two separate applications demonstrate this mechanism. The first application is a toolkit that allows for the testing of multiple routing related protocols in various combinations without code re-compilation or scenario re-generation. The toolkit produced similar results as the same …

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Multi-Reference Frame Image Registration For Rotation, Translation, And Scale, Christopher S. Costello Mar 2008

Multi-Reference Frame Image Registration For Rotation, Translation, And Scale, Christopher S. Costello

Theses and Dissertations

This thesis investigates applications of multi-reference frame image registration for image sets with various translation, rotation, and scale combinations. It focuses on registration accuracy improvement over traditional pairwise registration, and also compares the quality of scene estimation from frame averaging. Three experiments are developed which use cross-correlation to estimate translation, the Radon transform to estimate translation and rotation, and the Fourier-Mellin transform to estimate translation, rotation, and scale. Results from applying multi-reference frame registration in these experiments show distinct improvements in both registration accuracy and quality of frame averaging compared to single-reference frame registration. Furthermore, it is shown that the …

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Characterization And Implementation Of A Real-World Target Tracking Algorithm On Field Programmable Gate Arrays With Kalman Filter Test Case, Benjamin D. Hancey Mar 2008

Characterization And Implementation Of A Real-World Target Tracking Algorithm On Field Programmable Gate Arrays With Kalman Filter Test Case, Benjamin D. Hancey

Theses and Dissertations

A one dimensional Kalman Filter algorithm provided in Matlab is used as the basis for a Very High Speed Integrated Circuit Hardware Description Language (VHDL) model. The JAVA programming language is used to create the VHDL code that describes the Kalman filter in hardware which allows for maximum flexibility. A one-dimensional behavioral model of the Kalman Filter is described, as well as a one-dimensional and synthesizable register transfer level (RTL) model with optimizations for speed, area, and power. These optimizations are achieved by a focus on parallelization as well as careful Kalman filter sub-module algorithm selection. Newton-Raphson reciprocal is the …

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Signal Processing Design Of Low Probability Of Intercept Waveforms, Nathaniel C. Liefer Mar 2008

Signal Processing Design Of Low Probability Of Intercept Waveforms, Nathaniel C. Liefer

Theses and Dissertations

This thesis investigates a modification to Differential Phase Shift Keyed (DPSK) modulation to create a Low Probability of Interception/Exploitation (LPI/LPE) communications signal. A pseudorandom timing offset is applied to each symbol in the communications stream to intentionally create intersymbol interference (ISI) that hinders accurate symbol estimation and bit sequence recovery by a non-cooperative receiver. Two cooperative receiver strategies are proposed to mitigate the ISI due to symbol timing offset: a modified minimum Mean Square Error (MMSE) equalization algorithm and a multiplexed bank of equalizer filters determined by an adaptive Least Mean Square (LMS) algorithm. Both cooperative receivers require some knowledge …

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Development And Flight Of A Robust Optical-Inertial Navigation System Using Low-Cost Sensors, Michael B. Nielsen Mar 2008

Development And Flight Of A Robust Optical-Inertial Navigation System Using Low-Cost Sensors, Michael B. Nielsen

Theses and Dissertations

This research develops and tests a precision navigation algorithm fusing optical and inertial measurements of unknown objects at unknown locations. It provides an alternative to the Global Positioning System (GPS) as a precision navigation source, enabling passive and low-cost navigation in situations where GPS is denied/unavailable. This paper describes two new contributions. First, a rigorous study of the fundamental nature of optical/inertial navigation is accomplished by examining the observability grammian of the underlying measurement equations. This analysis yields a set of design principles guiding the development of optical/inertial navigation algorithms. The second contribution of this research is the development and …

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Effects Of Multipath And Oversampling On Navigation Using Orthogonal Frequency Division Multiplexed Signals Of Opportunity, Christopher M. Schexnayder Mar 2008

Effects Of Multipath And Oversampling On Navigation Using Orthogonal Frequency Division Multiplexed Signals Of Opportunity, Christopher M. Schexnayder

Theses and Dissertations

The Global Positioning System (GPS) has become the primary system for navigation and precise positioning. GPS has limitations, though, and is not suitable in environments where a line-of-site (LOS) path to multiple satellites is not available. Reliable alternatives need to be developed to provide GPS-like positioning when GPS is unavailable. One such alternative is to use signals of opportunity (SoOP). This concept refers to navigation using signals which inherently exist in the environment and were developed for non-navigation applications. This research focuses on exploiting the Orthogonal Frequency Division Multiplexed (OFDM) signal for the purpose of navigation. An algorithm was developed …

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Hardware Algorithm Implementation For Mission Specific Processing, Jason W. Shirley Mar 2008

Hardware Algorithm Implementation For Mission Specific Processing, Jason W. Shirley

Theses and Dissertations

There is a need to expedite the process of designing military hardware to stay ahead of the adversary. The core of this project was to build reusable, synthesizeable libraries to make this a possibility. In order to build these libraries, Matlab® commands and functions, such as Conv2, Round, Floor, Pinv, etc., had to be converted into reusable VHDL modules. These modules make up reusable libraries for the Mission Specific Process (MSP) which will support AFRL/RY. The MSP allows the VLSI design process to be completed in a mere matter of days or months using an FPGA or ASIC design, as …

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Hyperspectral-Augmented Target Tracking, Neil A. Soliman Mar 2008

Hyperspectral-Augmented Target Tracking, Neil A. Soliman

Theses and Dissertations

With the global war on terrorism, the nature of military warfare has changed significantly. The United States Air Force is at the forefront of research and development in the field of intelligence, surveillance, and reconnaissance that provides American forces on the ground and in the air with the capability to seek, monitor, and destroy mobile terrorist targets in hostile territory. One such capability recognizes and persistently tracks multiple moving vehicles in complex, highly ambiguous urban environments. The thesis investigates the feasibility of augmenting a multiple-target tracking system with hyperspectral imagery. The research effort evaluates hyperspectral data classification using fuzzy c-means …

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Determining The Surface-To-Air Missile Requirement For Western And Southern Part Of The Turkish Air Defense System, Omer Alkanat Mar 2008

Determining The Surface-To-Air Missile Requirement For Western And Southern Part Of The Turkish Air Defense System, Omer Alkanat

Theses and Dissertations

An air defense system is vital for countries to protect their homelands. Today, air defense systems consist of integrated systems such as early warning radars, fighter aircraft, airborne early warning aircraft and surface-to-air missile (SAM) systems. The Turkish air defense system does not have long range SAM systems. Turkey plans to procure SAM systems to protect her borders. This research develops two location optimization models to optimally locate SAM sites to defend specified areas of the nation. One of the models finds the minimum number of SAM sites to cover the specified area; the other finds the maximum coverage for …

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Discrete Event Simulation Of A Suppression Of Enemy Air Defenses (Sead) Mission, Ahmet Aydin Candir Mar 2008

Discrete Event Simulation Of A Suppression Of Enemy Air Defenses (Sead) Mission, Ahmet Aydin Candir

Theses and Dissertations

Contemporary military campaigns increasingly count on the use of air power. Suppression of enemy air defenses (SEAD) operations have been a crucial element of military air power for 50 years. Several developments and evolution in both air defense and attack systems suggest that SEAD missions will continue to have growing importance to air forces. Since SEAD operations have a significant impact on air campaigns, it is important to examine their efficiency and identify improvement opportunities. This study explores factors that influence SEAD operations through use of a discrete event simulation built in Arena and subsequent statistical analysis of the results.

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Robust Aircraft Squadron Scheduling In The Face Of Absenteeism, Osman Bahadir Gokcen Mar 2008

Robust Aircraft Squadron Scheduling In The Face Of Absenteeism, Osman Bahadir Gokcen

Theses and Dissertations

Air Force fighter aircraft squadrons the world over share a unique problem. Each requires complex training schedules coupling aircraft to pilots, the duo to missions and airspaces, and then the entire combination to a feasible time slot. Creating daily and weekly flight schedules that include shifts around the clock every day of the year with a set number of pilots is a time consuming job for manual schedulers within a squadron. Complicating matters is absenteeism. If one or more pilots are unable to perform their previously assigned tasks, due to sickness, aircraft failure, or reassignment, those tasks must be performed …

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Combat Identification Modeling Using Robust Optimization Techniques, Taeho Kim Mar 2008

Combat Identification Modeling Using Robust Optimization Techniques, Taeho Kim

Theses and Dissertations

The purposes of this research were: (1) the modeling of a CID situation and (2) the search for robust and controllable input variable settings. The inputs were defined as controllable and noise variables and the confusion matrices in ROC theory were adapted to act as controllable factors. In this research a simple virtual battlespace representation is employed. The experimental results of the CID system are summarized by a posterior confusion matrix and throughout the confusion matrix analysis we can obtain all various types of data such as accuracy, error cost, error rates, and so forth. To find the optimal parameters …

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Simulation Of National Intelligence Process With Fusion, Joseph S. Lupa Mar 2008

Simulation Of National Intelligence Process With Fusion, Joseph S. Lupa

Theses and Dissertations

This work is a follow on effort of two previous Master's theses. The first was Modeling and Simulation of the Military Intelligence Process by Captain Carl Pawling in 2004. The other was A Knowledge Matrix Modeling of the Intelligence Cycle by Captain Kevin Whaley in 2005. Both of these were done to facilitate the study and analysis of the intelligence process for the National Security Space Organization (NSSO). Here, modifications are made the Pawling model to include tasking multiple intelligence sources for data collection to fulfill Requests for Information (RFIs) and fusing the collected data into one new piece of …

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Robust Sensitivity Analysis Of Courses Of Action Using An Additive Value Model, Hunter A. Marks Mar 2008

Robust Sensitivity Analysis Of Courses Of Action Using An Additive Value Model, Hunter A. Marks

Theses and Dissertations

The Department of Defense (DoD) requires the ability to quantifiably measure progress in arenas that are complex and difficult to measure, such as the stability of a region. Therefore, the DoD works diligently to predict the effect of operations and sponsors research to improve prediction and analysis. They desire a repeatable, systematic methodology to aid in the selection of courses of action (COA) that efficiently meet stated objectives and quantitatively measure the degree of accomplishment of these objectives. The author proposes a value-focused thinking (VFT) decision analysis (DA) approach to this problem. This methodology not only aids in selection of …

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Assessing Capabilities Of The High Energy Liquid Laser Area Defense System Through Combat Simulations, Ryan S. Ponack Mar 2008

Assessing Capabilities Of The High Energy Liquid Laser Area Defense System Through Combat Simulations, Ryan S. Ponack

Theses and Dissertations

High Energy Laser (HEL) technology continues to improve and its place in the battlefield is ever evolving. By combining the high energy delivery of solid state laser technology with the efficient thermal management of liquid laser technology, HELLADS has two main advantages over any HEL predecessors. One, the configuration is small and light enough to be carried on more tactical aircraft such as fighters. Two, the thermal management greatly increases HEL fire power by increasing dwell time on target. To assess HELLADS operational capabilities the test community has been challenged with how to effectively examine the advantages and limitations through …

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Developing An Excel Decision Support System Using In-Transit Visibility To Decrease Dod Transportation Delays, Brian B. Stone Mar 2008

Developing An Excel Decision Support System Using In-Transit Visibility To Decrease Dod Transportation Delays, Brian B. Stone

Theses and Dissertations

The United States Air Force's Air Mobility Command (AMC) is responsible for efficiently transporting military personnel and cargo throughout the world. Organizations throughout the transportation system search for ways to decrease cargo transportation time as part of their ongoing mission to provide timely airlift services to the DoD. As cargo is transported through the transportation system it is in one of two states; waiting at an air base for transportation or in some phase of the loading, transportation, or unloading process. The loading and unloading process has been streamlined throughout the transportation system to a point which leaves little room …

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A Simulation Optimization Approach To The Design Of Unmanned Aircraft Systems, Emily C. Evans Mar 2008

A Simulation Optimization Approach To The Design Of Unmanned Aircraft Systems, Emily C. Evans

Theses and Dissertations

Military strategy and operations have evolved significantly over the past decade. This evolution has led to a change in the military resources required to carry out missions successfully. In line with these requirements, demand has increased for unmanned aerial vehicles (UAV) with enhanced capability to perform surveillance and to strike targets of interest. This research effort aids in the design of a next generation UAV by employing a simulation optimization approach. The goal of this research is to maximize the number of targets destroyed in a conflict scenario by a newly designed UAV that is subject to size, weight, and …

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Forecasting Instability Indicators In The Horn Of Africa Region, Bryan R. Tannehill Mar 2008

Forecasting Instability Indicators In The Horn Of Africa Region, Bryan R. Tannehill

Theses and Dissertations

The forecasting of state failure and the associated indicators has been a topic of great interest to a number of different agencies. USAID, CENTCOM, the World Bank, the Center for Army Analyses, and others have all examined the subject based on their own specific objectives. Whether the goal is denying terrorists space in which to operate, deciding how to pre-position materials in anticipation of unrest, stabilizing foreign markets and trade, or preventing or mitigating humanitarian disasters, man made or otherwise, this topic has been of interest for over a decade. The Horn of Africa has been one of the least …

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A Decision Tool To Evaluate Budgeting Methodologies For Estimating Facility Recapitalization Requirements, Krista M. Hickman Mar 2008

A Decision Tool To Evaluate Budgeting Methodologies For Estimating Facility Recapitalization Requirements, Krista M. Hickman

Theses and Dissertations

The purpose of this research was to develop a decision tool to assist in the evaluation of facility recapitalization budget estimation models to determine which model was best suited for a particular organization. Specifically, this thesis sought to answer an overarching research question addressing the importance of recapitalization and the best method to estimate the facility recapitalization budget using the Department of Defense (DoD) as the subject of the research. A comprehensive literature review revealed ten existing recapitalization model alternatives to consider for implementation. The methodology used to develop a decision tool was based on the Value Focused Thinking (VFT) …

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Simulated Multi-Echelon Readiness-Based Inventory Leveling With Lateral Resupply, Todd C. Burnworth Mar 2008

Simulated Multi-Echelon Readiness-Based Inventory Leveling With Lateral Resupply, Todd C. Burnworth

Theses and Dissertations

For the past fifty years, U.S. Air Force reparable inventory has been allocated based on an analytic model developed by Dr. Craig C. Sherbrooke. Although versions of his model can be implemented easily with the help of a computer, the analytic approach fundamentally lacks the flexibility to address numerous logistics issues. This body of research will offer a novel alternative approach that will enable researchers to investigate currently unsolved logistics problems such as quantifying the benefits of lateral resupply.

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Simulation Modeling And Analysis Of F-16 Pilot Training Squadron, Adem Okal Mar 2008

Simulation Modeling And Analysis Of F-16 Pilot Training Squadron, Adem Okal

Theses and Dissertations

The need for fighter pilots in the Turkish Air Force is expected to increase with the planned acquisition of Joint Strike Fighters, ongoing new F-16 purchases, and other upgrades to the Turkish Air Force fighter inventory. This increased demand will affect the current fighter training squadron curriculum and scheduling. This study focuses on issues related to 143rd Oncel squadron F-16 Pilot Training with this projected increase in number of student pilots (SP). Completing the training periods on time is an important issue along with maintaining effective training performance. In our study the Total Time of the training period serves …

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The Impact Of Operations Tempo (Optempo) On Intentions To Depart The Military. Does The Increase Of Optempo Cause Action, Nathan P. Olsen Mar 2008

The Impact Of Operations Tempo (Optempo) On Intentions To Depart The Military. Does The Increase Of Optempo Cause Action, Nathan P. Olsen

Theses and Dissertations

Recent information in the field of Operations Tempo (OPTEMPO) has resulted in conflicting information on its effect on turnover intentions. This study evaluated the August 2004 Status of Forces Survey to determine if the sample demonstrated OPTEMPO had a curvilinear effect on turnover intentions when accounting for the moderators job satisfaction and organizational commitment while controlling for rank and gender. Linear regressions were used to determine if the relationship between OPTEMPO and turnover intentions were significant. When accounting for job satisfaction and organizational commitment the relationship between OPTEMPO and turnover intentions is not significant, this indicated that OPTEMPO and turnover …

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Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger Mar 2008

Linking Embeddedness And Macroinvertebrate In Two Southwest Ohio Streams, Jonathan P. Kochersberger

Theses and Dissertations

Environmental managers utilize a variety of tools when assessing lotic systems for stressors attributed to anthropogenic sources. Stream deposited sediment has been recognized as one of the major stressors affecting streams in the U.S. The detrimental effect on aquatic biota of sediment depositing within the interstitial spaces of stream substrate (embeddedness) has been established, yet lacking is an effective in situ method of quantifying embeddedness over short time periods. The goal of this research was to develop a short-term embeddedness (EMB) quantification method that can be linked to benthic macroinvertebrate health. Such a method would be a valuable tool when …

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Risk-Based Comparison Of Classification Systems, Seth B. Wagenman Mar 2008

Risk-Based Comparison Of Classification Systems, Seth B. Wagenman

Theses and Dissertations

Performance measures for families of classification system families that rely upon the analysis of receiver operating characteristics (ROCs), such as area under the ROC curve (AUC), often fail to fully address the issue of risk, especially for classification systems involving more than two classes. For the general case, we denote matrices of class prevalences, costs, and class-conditional probabilities, and assume costs are subjectively fixed, acceptable estimates for expected values of class-conditional probabilities exist, and mutual independence between a variable in one such matrix and those of any other matrix. The ROC Risk Functional (RRF), valid for any finite number of …

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Velocity Estimate Following Air Data System Failure, Scott A. Mclaren Mar 2008

Velocity Estimate Following Air Data System Failure, Scott A. Mclaren

Theses and Dissertations

Modern high performance aircraft can provide amazing performance due in part to their advanced flight control systems that require gain scheduling to provide optimum performance over a huge flight envelope. In modern fighter aircraft, this gain scheduling is a function of airspeed, and almost all of the research involving aircraft gain scheduling assumes aircraft airspeed to be a known quantity. The purpose of this research was to investigate a method of determining an aircraft’s airspeed in the event of total air data system failure. The process began by combining known aircraft information following an air data system failure to determine …

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