Digital Commons Network^™

Micro-Etched Platforms For Thermal Inactivation Of Bacillus Anthracis And Bacillus Thuringiensis Spores, Leslie S. Hawkins

Theses and Dissertations

This research developed and applied microlithography techniques to etch microscope slide platforms in order to measure thermal inactivation of Bacillus thuringiensis and Bacillus anthracis spores, two closely related Bacillus species. B.t. is widely used as a surrogate for B.a. in response studies and in some field studies. This work addressed the previously identified problem of measuring both spore growth and spore thermal kill threshold using the traditional method of spreading a diluted spore solution on a plate. The micro-etched platforms forced spore separation thereby preventing neighbor growth from obscuring germination and initial vegetative growth measurements using a microscope. The technique …

A Static Aeroelastic Analysis Of A Flexible Wing Mini Unmanned Aerial Vehicle, Nathan A. Pitcher

Theses and Dissertations

The static aeroelastic behavior of the Nighthawk mini unmanned aerial vehicle is examined using a combined experimental and computational approach. Three wings are examined. In order of increasing stiffness they are: a flexible wing, a stiff wing, and a fictitious rigid wing with zero deflection. Photogrammetry is used during wind tunnel testing to measure the average deflected shape of the flexible and stiff wings during flight. The independent variables during wind tunnel tests are angle of attack (ranging from −5.1° through 13.4°) and velocity, which is 20 mph, 30 mph, and 40 mph. Roll angle and yaw angle are control …

C-5a Galaxy Systems Engineering Case Study, Air Force Center For Systems Engineering, John M. Griffin

AFIT Documents

The C-5 Systems Engineering Case Study captures the untold story of the application of systems engineering during the concept exploration, development, and production of the USAF C-5A and C-5B aircraft. The case study examines and dissects the systems engineering process as applied by the Air Force C-5 System Program Office and the prime contractor, Lockheed, Georgia, from the program s genesis in 1957 to the last delivery of the C-5A and the beginning of the C-5B program in 1973. Numerous interviews were conducted with the principals who managed and directed the program and a story of the systems engineering process …

Hubble Space Telescope Systems Engineering Case Study, Air Force Center For Systems Engineering, James J. Mattice

AFIT Documents

The Hubble Space Telescope (HST) is an orbiting astronomical observatory operating in the spectrum from the near-infrared into the ultraviolet. Launched in 1990 and scheduled to operate through 2010, HST carries and has carried a wide variety of instruments producing imaging, spectrographic, astrometric, and photometric data through both pointed and parallel observing programs. Over 100,000 observations of more than 20,000 targets have been produced for retrieval. A macroscopic, cumulative representation of these observations is shown in the figure below to provide a sense of the enormous volume of astronomical data collected by the HST about our universe, our beginnings, and, …

Understanding The Emergence Of Disruptive Innovation In The Air Force Science And Technology Organizations, David E. Shahady

Theses and Dissertations

Although innovation is widely discussed in both military and industry venues, many organizations continue to struggle with what it means to be creative as well as maintain a competitive advantage. The United States Air Force has specifically struggled with the balance between improving existing technologies and employing revolutionary technologies. The purpose of this thesis was to study the motivation, focus, barriers, and culture needed to foster disruptive innovation in Air Force Science and Technology (S&T) and to investigate how industry innovation strategies could improve breakthrough Air Force technology emergence. The Air Force Research Laboratory (AFRL), the primary organization responsible for …

Extending Cfd Modeling To Near-Continuum Flows Using Enhanced Thermophysical Modeling, Abram E. Claycomb

Theses and Dissertations

The constitutive relations found in traditional Navier-Stokes-based computational fluid dynamics solvers are known to be limited in altitude. The presence of nonequilibrium phenomena beyond what these methods are able to predict becomes more prevalent at higher altitudes, or increasing Knudsen number. The bulk viscosity, normally assumed to be zero in most computational fluid dynamics applications, is examined as a means of increasing the range of applicability of computational fluid dynamics. The bulk viscosity model used was from recent calculations available in the literature, from a new anisotropic potential energy surface, and is restricted to temperatures below 2000 K. The normal …

Dialable Cryptography For Wireless Networks, Marnita T. Eaddie

Theses and Dissertations

The objective of this research is to develop an adaptive cryptographic protocol, which allows users to select an optimal cryptographic strength and algorithm based upon the hardware and bandwidth available and allows users to reason about the level of security versus the system throughput. In this constantly technically-improving society, the ability to communicate via wireless technology provides an avenue for delivering information at anytime nearly anywhere. Sensitive or classified information can be transferred wirelessly across unsecured channels by using cryptographic algorithms. The research presented will focus on dynamically selecting optimal cryptographic algorithms and cryptographic strengths based upon the hardware and …

Increasing Combat Aircraft Survivability Through Coherent Self-Protection Jammers, Soner Ozer

Theses and Dissertations

When the battlefields were within the visual range, the objective of deception tactics in warfare was to deceive the human senses. In the battlefield of electromagnetic spectrum, the objective of deception is to deceive the sensors of the enemy weapon systems. The survivability of the aircraft operating in hostile environment is of prime importance to the mission planner. If the aircraft can deny its location information to the tracking radar of the radar guided threat missile system, this, in return, may increase its survivability. The deception, a tactic which stems from the wisdom of ancient battles, incarnated in the form …

Improvement Of Ecm Techniques Through Implementation Of A Genetic Algorithm, James D. Townsend

Theses and Dissertations

This research effective effort develops the necessary interfaces between the radar signal processing components and an optimization routine, such as genetic algorithms, to develop Electronic Countermeasure (ECM) waveforms under a Hardware-in-the-Loop (HILS) architecture. The various ECM waveforms are stored in an ECM library, where an operator selects the desired function to use against a particular system. This optimization works with modular components, compared to previous research that embedded a genetic algorithm into the Range Gate Pull-off (RGPO) waveform optimization loop, which can be interchanged based upon the operator's desired hardware/ software testing setup. The ECM library's first entries contain the …

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 …

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 …

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 …

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 …

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 …

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.

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 …

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 …

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 …

Digital Fingerprinting Of Field Programmable Gate Arrays, James W. Crouch

Theses and Dissertations

Commercial off-the-shelf (COTS) component usage is becoming more prevalent in military applications due to current Department of Defense (DoD) policies. The easy accessibility of COTS will give reverse engineers a higher probability of successfully tampering, coping, or reverse engineering circuits that contain critical capabilities. To prevent this and verify the trustworthiness of hardware, circuit identification tags or serials numbers can be used. However, these values can be easily obtained and forged. To protect critical DoD technologies from possible exploitation, there is an urgent need for a reliable method to confirm a circuit’s identity using a set of unique unforgettable metrics. …

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 …

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 …

Integration Of Information Operations Theory Into The Corporate Air Force, Thomas R. Kettles Jr.

Theses and Dissertations

The purpose of this research was to determine the desired end-state for company grade officers in terms of an information operations education. Specifically, an examination of company grade officer curricula from the pre-commissioning sources to the Squadron Officer College was performed. This assessment was then compared to the Air Force Institute of Technology Cyber Competency Areas Framework. Any areas that were missing from the current company grade officer curricula were identified and a proposed implementation plan was presented to correct these deficiencies. To aid in developing an implementation plan, redundancies between the two Squadron Officer College courses were identified. Furthermore, …

Integrating Through-Wafer Interconnects With Active Devices And Circuits, Jim Jozwiak, Richard G. Southwick Iii, Vaughn N. Johnson, William B. Knowlton, Amy J. Moll

Electrical and Computer Engineering Faculty Publications and Presentations

Through wafer interconnects (TWIs) enable vertical stacking of integrated circuit chips in a single package. A complete process to fabricate TWIs has been developed and demonstrated using blank test wafers. The next step in integrating this technology into 3D microelectronic packaging is the demonstration of TWIs on wafers with preexisting microcircuitry. The circuitry must be electrically accessible from the backside of the wafer utilizing the TWIs; the electrical performance of the circuitry must be unchanged as a result of the TWI processing; and the processing must be as cost effective as possible. With these three goals in mind, several options …

A Systematic Approach For Securing Our Space Assets, Heather Yates, Michael R. Grimaila

Faculty Publications

We are surrounded by the use of space assets, but for the most part are unaware of their impact on our lives. On a daily basis, space assets contribute to our well-being and others around the world. Space activities have enhanced security, monitored the environment, improved and increased information growth and flow, created economic growth, and changed the way people around the world live and work.[1] Since the 1991 Gulf War, we have also come to understand how much the US military depends on space. Military forces use satellite information for communications, intelligence, surveillance, reconnaissance, warning, weather, navigation, and timing. …

Hardware/Software Codesign In A Compact Ion Mobility Spectrometer Sensor Systemfor Subsurface Contaminant Detection, Sin Ming Loo, Jonathan P. Cole, Molly M. Gribb

Electrical and Computer Engineering Faculty Publications and Presentations

A field-programmable-gate-array-(FPGA-) based data acquisition and control system was designed in a hardware/software codesign environment using an embedded Xilinx Microblaze soft-core processor for use with a subsurface ion mobility spectrometer (IMS) system, designed for detection of gaseous volatile organic compounds (VOCs). An FPGA is used to accelerate the digital signal processing algorithms and provide accurate timing and control. An embedded soft-core processor is used to ease development by implementing nontime critical portions of the design in software. The design was successfully implemented using a low-cost, off-the-shelf Xilinx Spartan-III FPGA and supporting digital and analog electronics.

Quantum Dot / Optical Protein Bio-Nano Hybrid System Biosensing, Mark H. Griep

Dissertations, Master's Theses and Master's Reports - Open

The integration of novel nanomaterials with highly-functional biological molecules has advanced multiple fields including electronics, sensing, imaging, and energy harvesting. This work focuses on the creation of a new type of bio-nano hybrid substrate for military biosensing applications. Specifically it is shown that the nano-scale interactions of the optical protein bacteriorhodopsin and colloidal semiconductor quantum dots can be utilized as a generic sensing substrate.

This work spans from the basic creation of the protein to its application in a novel biosensing system. The functionality of this sensor design originates from the unique interactions between the quantum dot and bacteriorhodopsin molecule …

Mems (Micro-Electro-Mechanical-Systems) Based Microfluidic Platforms For Magnetic Cell Separation, Pulak Nath

ETD Archive

Microfluidic platforms for magnetic cell separation were developed and investigated for isolation of magnetic particles and magnetically tagged cells from a fluidic sample. Two types of magnetic separation platforms were considered: an Isodynamic Open Gradient Magnetic Sorter (OGMS) and a multistage bio-ferrograph. Miniaturized magnets were designed using magnetostatic simulation software, microfluidic channels were fabricated using microfabrication technology and magnetic separation was investigated using video microscopy and digital image processing. The isodynamic OGMS consisted of an external magnetic circuit and a microfabricated channel (biochip) with embedded magnetic elements. The biochip is placed inside the magnetic field of the external circuit to …

Vietnam: Historians At War, Mark Moyar

United States Army: Publications

By the early 1990s, when I began studying the Vietnam War, the American public had largely lost interest in the history of that conflict. The Civil War and World War II were the wars that historians were advised to cover if they wanted to reach the public. Among government officials, military officers, and political scientists, Vietnam was considered irrelevant, because the United States would never get caught in protracted counterinsurgency warfare again. Iraq changed all that. Ever since the outbreak of insurgency in the former empire of Saddam Hussein, people of all persuasions have been mining the history of Vietnam …

The 2008 Strategy For United States Air Force Intelligence, Surveillance And Reconnaissance, United States Air Force

United States Air Force: Publications

Since the inception of the Air Force, our Nation has asked us to create aerospace forces that no adversary could "out gun" under any circumstances. For over six decades we have answered that call. Now the Nation demands that we also create a set of capabilities that no adversary can "out smart" in the future. This strategy outlines our response in the realm of Intelligence, Surveillance and Reconnaissance (ISR).
This is a new document that specifies why and how our Air Force will provide the capacity and capability for full spectrum ISR. It provides the foundation for enabling our air …

Factors Affecting The Spread Of A Bioterrorist Agent Throughout A Building, William A. Cantrell

Inquiry: The University of Arkansas Undergraduate Research Journal

Bioterrorism has become a greater concern for Americans since the 2001 anthrax letters. Recent studies have explored the possibilities of biological attacks, and most deal with possible large-scale attacks. However, there is reason to believe that small-scale attacks are more likely. Even though there have been investigations of the postal delivery system and the spread of bioagents through mail, few if any studies have looked at attack on a single building and the resultant spread form room to room. One particular method of attacking a building would be a single-even release of an aerosol bioagent in the building. This paper …