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Fiber Optic Sensor Interrogation Advancements For Research And Industrial Use, Wesley Mont Kunzler 2011 Brigham Young University - Provo

Fiber Optic Sensor Interrogation Advancements For Research And Industrial Use, Wesley Mont Kunzler

Theses and Dissertations

Spectrally-based fiber optic sensors are a rapidly maturing technology capable of sensing several environmental parameters in environments that are unfitting to electrical sensors. However, the sensor interrogation systems for this type of sensors are not yet fit to replace conventional sensor systems. They lack the speed, compact size, and usability necessary to move into mainstream test and measurement. The Fiber Sensor Integrated Monitor (FSIM) technology leverages rapid optical components and parallel hardware architecture to move these sensors across the research threshold into greater mainstream use. By dramatically increasing speed, shrinking size, and targeting an interface that can be used in …


Development Of Single-Chip Silicon Photonic Microcantilever Arrays For Sensing Applications, Weisheng Hu 2011 Brigham Young University - Provo

Development Of Single-Chip Silicon Photonic Microcantilever Arrays For Sensing Applications, Weisheng Hu

Theses and Dissertations

Microcantilever arrays have been shown to be promising label-free nanomechanical sensing devices with high sensitivity. Two factors that affect the usefulness of microcantilevers in sensing scenarios are the sensitivity of the transduction method for measuring changes in microcantilever properties and the ability to create large compact arrays of microcantilevers. In this dissertation, we demonstrate that microcantilevers with an in-plane photonic transduction method are attractive because they maintain the sensitivity of the traditional laser beam reflection method while being scalable to simultaneous readout of large microcantilever arrays. First I demonstrate the integration of a compact waveguide splitter network with in-plane photonic …


Increasing Design Productivity For Fpgas Through Ip Reuse And Meta-Data Encapsulation, Adam T. Arnesen 2011 Brigham Young University - Provo

Increasing Design Productivity For Fpgas Through Ip Reuse And Meta-Data Encapsulation, Adam T. Arnesen

Theses and Dissertations

As Moore's law continues to progress, it is becoming increasingly difficult for hardware designers to fully utilize the increasing number of transistors available semiconductor devices including FPGAs. This design productivity gap must be addressed to allow designs to take full advantage of the increased logic density that results from rising transistor density. The reuse of previously developed and verified intellectual property (IP) is one approach that has claimed to narrow the design productivity gap. Reuse, however, has proved difficult to realize in practice because of the complexity of IP and the reluctance of designers to reuse IP that they do …


Increasing Efficiency In Boundary Security With Wireless Sensor Networks And Geospatial Information Systems Using Homology Theory, Luis Berumen^, Eric Chaidez^, Hamide Dogan*, Jose Gerardo Rosiles** 2011 University of Texas at El Paso

Increasing Efficiency In Boundary Security With Wireless Sensor Networks And Geospatial Information Systems Using Homology Theory, Luis Berumen^, Eric Chaidez^, Hamide Dogan*, Jose Gerardo Rosiles**

COURI Symposium Abstracts, Spring 2011

As part of an institutional investigation, we attempt to address the challenges the US customs and Border protection agency faces in the El Paso region. Our research focuses on defining a system for the surveillance application, and the use of mathematical models employed to achieve a greater efficiency of such architecture. With the use of the defined system, we apply homology theory through the algebraic process of topology, to accomplish an independent coordinate-free based system, which covers the surveillance area, with lesser quantity of sensor nodes. Our architecture makes the use of an operating system for wireless sensor networks; TinyOS, …


System Identification, State Estimation, And Control Of Unmanned Aerial Robots, Caleb H. Chamberlain 2011 Brigham Young University - Provo

System Identification, State Estimation, And Control Of Unmanned Aerial Robots, Caleb H. Chamberlain

Theses and Dissertations

This thesis describes work in a variety of topics related to aerial robotics, including system identification, state estimation, control, and path planning. The path planners described in this thesis are used to guide a fixed-wing UAV along paths that optimize the aircraft's ability to track a ground target. Existing path planners in the literature either ignore occlusions entirely, or they have limited capability to handle different types of paths. The planners described in this thesis are novel in that they specifically account for the effect of occlusions in urban environments, and they can produce a much richer set of paths …


Shaped Mems Contact, Ronald A. Coutu Jr., Paul E. Kladitis, Robert L. Crane 2011 Air Force Institute of Technology

Shaped Mems Contact, Ronald A. Coutu Jr., Paul E. Kladitis, Robert L. Crane

AFIT Patents

A MEMS switch fabrication process and apparatus inclusive of a bulbous rounded surface movable contact assembly that is integral with the switch movable element and achieving of long contact wear life with low contact electrical resistance. The disclosed process is compatible with semiconductor integrated circuit fabrication materials and procedures and includes an unusual photoresist reflow step in which the bulbous contact shape is quickly defined in three dimensions from more easily achieved integrated circuit mask and etching-defined precursor shapes. A plurality of differing photoresist materials are used in the process. A large part of the contact and contact spring formation …


Ultrasensitive Biosensing On The Zepto-Molar Level, Yongki Choi, Siu-Tung Yau 2011 City University of New York

Ultrasensitive Biosensing On The Zepto-Molar Level, Yongki Choi, Siu-Tung Yau

Electrical and Computer Engineering Faculty Publications

Detection of analytes on the zepto-molar (10^-^2^1M) level has been achieved using a field-effect bio-detector. By applying a gating voltage to enzymes immobilized on the working electrode of the detector, amplification of the biocatalytic current was observed. The amplification is attributed to the modification of the tunnel barrier between the enzyme and the electrode by the gating voltage-induced electric field which exists at the solution-electrode interface. The detection was demonstrated with the glucose oxidase (GOx)-glucose and alcohol dehydrogenase (ADH)-ethanol biocatalytic systems. Glucose at zepto-molar level was detected with zepto-molar detection resolution. Equivalently, 30 glucose …


A High-Gain, Low-Power Cmos Operational Amplifier Using Composite Cascode Stage In The Subthreshold Region, Rishi Pratap Singh 2011 Brigham Young University - Provo

A High-Gain, Low-Power Cmos Operational Amplifier Using Composite Cascode Stage In The Subthreshold Region, Rishi Pratap Singh

Theses and Dissertations

This thesis demonstrates that the composite cascode differential stage, operating in the subthreshold region, can form the basis of a high gain (113 dB) and low-power op amp (28.1 µW). The circuit can be fabricated without adding a compensation capacitance. The advantages of this architecture include high voltage gain, low bandwidth, low harmonic distortion, low quiescent current and power, and small chip area. These advantages suggest that this design might be well-suited for biomedical applications where low power, low noise bio-signal amplifiers capable of amplifying signals in the millihertz-to-kilohertz range is required.


Software And Critical Technology Protection Against Side Channel Analysis Through Dynamic Hardware Obfuscation, John R. Bochert 2011 Air Force Institute of Technology

Software And Critical Technology Protection Against Side Channel Analysis Through Dynamic Hardware Obfuscation, John R. Bochert

Theses and Dissertations

Side Channel Analysis (SCA) is a method by which an adversary can gather information about a processor by examining the activity being done on a microchip though the environment surrounding the chip. Side Channel Analysis attacks use SCA to attack a microcontroller when it is processing cryptographic code, and can allow an attacker to gain secret information, like a crypto-algorithm's key. The purpose of this thesis is to test proposed dynamic hardware methods to increase the hardware security of a microprocessor such that the software code being run on the microprocessor can be made more secure without having to change …


Blind Deconvolution Method Of Image Deblurring Using Convergence Of Variance, Quentin D. MacManus 2011 Air Force Institute of Technology

Blind Deconvolution Method Of Image Deblurring Using Convergence Of Variance, Quentin D. Macmanus

Theses and Dissertations

Images are used for both aerial and space imagery applications, including target detection and tracking. The current problem concerning objects in geosynchronous orbit is that they are dim and hard to resolve because of their distance. This work will further the combined effort of AFIT and AFRL to provide enhanced space situational awareness (SSA) and space surveillance. SSA is critical in a time when many countries possess the technology to put satellites into orbit. Enhanced imaging technology improves the Air Force's ability to see if foreign satellites or other space hardware are operating in the vicinity of our own assets …


Signals Of Opportunity Navigation Using Wi-Fi Signals, Wilfred E. Noel 2011 Air Force Institute of Technology

Signals Of Opportunity Navigation Using Wi-Fi Signals, Wilfred E. Noel

Theses and Dissertations

Since GPS is generally limited to areas with clear sky view, additional methods of navigation are currently being explored. This thesis explores navigation using Signals of Opportunity(SoOP). The signals chosen for evaluation in this thesis are the common Internet IEEE 802.11a/g signals, or Wi-Fi. This thesis presents SoOP navigation based on cross-correlations of received data from multiple Wi-Fi stations. It shows the effectiveness of the methods using collected Wi-Fi signals in a real-world environment. By using simple statistical representations of collected data in large groups, or windows, cross-correlation calculations can produce timing offsets between simulated stations. The timing offsets, or …


Evaluating Information Assurance Control Effectiveness On An Air Force Supervisory Control And Data Acquisition (Scada) System, Jason R. Nielsen 2011 Air Force Institute of Technology

Evaluating Information Assurance Control Effectiveness On An Air Force Supervisory Control And Data Acquisition (Scada) System, Jason R. Nielsen

Theses and Dissertations

Supervisory Control and Data Acquisition (SCADA) systems are increasingly being connected to corporate networks which has dramatically expanded their attack surface to remote cyber attack. Adversaries are targeting these systems with increasing frequency and sophistication. This thesis seeks to answer the research question addressing which Information Assurance (IA) controls are most significant for network defenders and SCADA system managers/operators to focus on in order to increase the security of critical infrastructure systems against a Stuxnet-like cyber attack. This research applies the National Institute of Science and Technology (NIST) IA controls to an attack tree modeled on a remote Stuxnet-like cyber …


Bistatic 3d Electromagnetic Scattering From A Right-Angle Dihedral At Arbitrary Orientation And Position, Andreas Z. Tempelis 2011 Air Force Institute of Technology

Bistatic 3d Electromagnetic Scattering From A Right-Angle Dihedral At Arbitrary Orientation And Position, Andreas Z. Tempelis

Theses and Dissertations

A method is created to extend a bistatic 3D electromagnetic scattering solution for a dihedral at a given orientation and position to the case of arbitrary orientation and position. Results produced using this method are compared to shooting and bouncing rays (SBR) and method of moments (MoM) predictions, as well as measured data for applicable cases. The model in this thesis shows excellent agreement in magnitude and phase with SBR predictions. It also shows good agreement in magnitude with MoM predictions. Small phase differences between model and MoM data occur due to differences in the underlying scattering solution and the …


Direction Finding With Mutually Orthogonal Antennas, David F. Chick 2011 Air Force Institute of Technology

Direction Finding With Mutually Orthogonal Antennas, David F. Chick

Theses and Dissertations

Estimating the direction-of-arrival of incident electromagnetic plane waves (a.k.a. direction finding or DF) has typically been accomplished in the past using arrays of spatially separated antennas. The spatial separation produces a delay in each antenna's measured voltage due to the finite propagation time as the wave strikes each antenna in succession. In this thesis, we approach the problem differently by using three antennas that have been oriented in orthogonal directions but are co-located at the origin of a coordinate system. Being co-located, this mutually orthogonal arrangement of antennas cannot detect the propagation phase delay and must rely solely on the …


Creating A Network Model For The Integration Of Dynamic And Static Supervisory Control And Data Acquisition (Scada) Test Environment, Marlon Coerbell 2011 Air Force Institute of Technology

Creating A Network Model For The Integration Of Dynamic And Static Supervisory Control And Data Acquisition (Scada) Test Environment, Marlon Coerbell

Theses and Dissertations

Since 9/11 protecting our critical infrastructure has become a national priority. Presidential Decision Directive 63 mandates and lays a foundation for ensuring all aspects of our nation's critical infrastructure remain secure. Key in this debate is the fact that much of our electrical power grid fails to meet the spirit of this requirement. My research leverages the power afforded by Electric Power and Communication Synchronizing Simulator (EPOCHS) developed with the assistance of Dr. Hopkinson, et al. The power environment is modeled in an electrical simulation environment called PowerWorld©. The network is modeled in OPNET® and populated with self-similar network and …


Dynamic Polymorphic Reconfiguration To Effectively “Cloak” A Circuit’S Function, Jeffrey L. Falkinburg 2011 Air Force Institute of Technology

Dynamic Polymorphic Reconfiguration To Effectively “Cloak” A Circuit’S Function, Jeffrey L. Falkinburg

Theses and Dissertations

Today's society has become more dependent on the integrity and protection of digital information used in daily transactions resulting in an ever increasing need for information security. Additionally, the need for faster and more secure cryptographic algorithms to provide this information security has become paramount. Hardware implementations of cryptographic algorithms provide the necessary increase in throughput, but at a cost of leaking critical information. Side Channel Analysis (SCA) attacks allow an attacker to exploit the regular and predictable power signatures leaked by cryptographic functions used in algorithms such as RSA. In this research the focus on a means to counteract …


Evaluation Of The Single Keybit Template Attack, Eric W. Garcia 2011 Air Force Institute of Technology

Evaluation Of The Single Keybit Template Attack, Eric W. Garcia

Theses and Dissertations

Side Channel leakage is a serious threat to secure devices. Cryptographic information extraction is possible after examining any one of the various side channels, including electromagnetic. This work contributes a new method to achieve such a purpose. The Single Keybit Template Attack (SKTA) is introduced as a means to extract encryption keys from embedded processors and other integrated circuit devices performing DES encryptions by passively monitoring and exploiting unintentional RF emissions. Key extraction is accomplished by creating two templates for each bit value of the key based on instantaneous amplitude responses as a device executes DES operations. The resultant templates …


Electromagnetic Modeling And Measurement Of Adaptive Metamaterial Structural Elements, Matthew E. Jussaume 2011 Air Force Institute of Technology

Electromagnetic Modeling And Measurement Of Adaptive Metamaterial Structural Elements, Matthew E. Jussaume

Theses and Dissertations

This document addresses two major obstacles facing metamaterial development: uncertainty in the characterization of electromagnetic field behavior in metamaterial structures and the relatively small operational bandwidth of metamaterial structures. To address the first obstacle, a method of prediction aided measurement is developed and exploited to examine the field interactions within metamaterial devices. The fusion of simulation and measurement techniques enhances the understanding of the physical interactions of fields in the presence of metamaterials. To address the second obstacle, this document characterizes the effectiveness of an adaptive metamaterial design that incorporates a microelectromechanical systems (MEMS) variable capacitor. Applying voltages to the …


Simultaneous Range/Velocity Detection With An Ultra-Wideband Random Noise Radar Through Fully Digital Cross-Correlation In The Time Domain, James R. Lievsay 2011 Air Force Institute of Technology

Simultaneous Range/Velocity Detection With An Ultra-Wideband Random Noise Radar Through Fully Digital Cross-Correlation In The Time Domain, James R. Lievsay

Theses and Dissertations

This research effort examines the theory, application, and results of applying two-dimensional cross-correlation in the time domain to ultra-wideband (UWB) random noise waveforms for simultaneous range and velocity estimation. When applying common Doppler processing techniques to random noise waveforms for the purpose of velocity estimation, the velocity resolution degrades as the signal bandwidth or the target speed increase. To mitigate the degradation, the Doppler approximation is not utilized, and instead, wideband signal processing theory is applied in the time domain. The results show that by accurately interpolating each sample in the digitized reference signal, a target's velocity and range can …


Improving The Efficiency Of Photon Collection By Compton Rescue, Alexander W. Stevenson 2011 Air Force Institute of Technology

Improving The Efficiency Of Photon Collection By Compton Rescue, Alexander W. Stevenson

Theses and Dissertations

A method to improve the efficiency of photon collection in thin planar HPGe detectors was investigated. The method involved implementing a second HPGe detector to collect Compton scattered photons from the primary detector and incorporating coincident interactions in the two detectors that sum to the full energy event into the energy spectrum. This method is termed Compton rescue because the Compton scattered photons make a partial energy deposition in the primary detector and are added back to the spectrum after being detected by the second detector. This research has implications on improving the efficiency of positron annihilation spectroscopy (PAS) techniques …


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