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2010

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Improving Range Estimation Of A 3d Flash Ladar Via Blind Deconvolution, Jason R. Mcmahon Sep 2010

Improving Range Estimation Of A 3d Flash Ladar Via Blind Deconvolution, Jason R. Mcmahon

Theses and Dissertations

The purpose of this research effort is to improve and characterize range estimation in a three-dimensional FLASH LAser Detection And Ranging (3D FLASH LADAR) by investigating spatial dimension blurring effects. The myriad of emerging applications for 3D FLASH LADAR both as primary and supplemental sensor necessitate superior performance including accurate range estimates. Along with range information, this sensor also provides an imaging or laser vision capability. Consequently, accurate range estimates would also greatly aid in image quality of a target or remote scene under interrogation. Unlike previous efforts, this research accounts for pixel coupling by defining the range image mathematical …

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Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon Sep 2010

Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon

Theses and Dissertations

This research extends the theory and understanding of the laser speckle imaging technique. This non-traditional imaging technique may be employed to improve space situational awareness and image deep space objects from a ground-based sensor system. The use of this technique is motivated by the ability to overcome aperture size limitations and the distortion effects from Earth’s atmosphere. Laser speckle imaging is a lensless, coherent method for forming two-dimensional images from their autocorrelation functions. Phase retrieval from autocorrelation data is an ill-posed problem where multiple solutions exist. This research introduces polarization diversity as a method for obtaining additional information so the …

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Determining The Index Of Refraction Of An Unknown Object Using Passive Polarimetric Imagery Degraded By Atmospheric Turbulence, Milo W. Hyde Iv Sep 2010

Determining The Index Of Refraction Of An Unknown Object Using Passive Polarimetric Imagery Degraded By Atmospheric Turbulence, Milo W. Hyde Iv

Theses and Dissertations

In this research, an algorithm is developed to estimate the index of refraction of an unknown object using passive polarimetric images degraded by atmospheric turbulence. The algorithm uses a variant of the maximum-likelihood blind-deconvolution algorithm developed by LeMaster and Cain to recover the true object (i.e., the first Stokes parameter), the degree of linear polarization, and the polarimetric-image point spread functions. Nonlinear least squares is then used to find the value of the complex index of refraction which best fits the theoretical degree of linear polarization, derived using a polarimetric bidirectional reflectance distribution function, to the turbulence-corrected degree of linear …

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Cyber Situational Awareness Using Live Hypervisor-Based Virtual Machine Introspection, Dustyn A. Dodge Sep 2010

Cyber Situational Awareness Using Live Hypervisor-Based Virtual Machine Introspection, Dustyn A. Dodge

Theses and Dissertations

In this research, a compiled memory analysis tool for virtualization (CMAT-V) is developed as a virtual machine introspection (VMI) utility to conduct live analysis during cyber attacks. CMAT-V leverages static memory dump analysis techniques to provide live dynamic system state data. Unlike some VMI applications, CMAT-V bridges the semantic gap using derivation techniques. CMAT-V detects Windows-based operating systems and uses the Microsoft Symbol Server to provide this context to the user. This research demonstrates the usefulness of CMAT-V as a situational awareness tool during cyber attacks, tests the detection of CMAT-V from the guest system level and measures its impact …

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Applying Image Matching To Video Analysis, Adam J. Behring Sep 2010

Applying Image Matching To Video Analysis, Adam J. Behring

Theses and Dissertations

Dealing with the volume of multimedia collected on a daily basis for intelligence gathering and digital forensics investigations requires significant manual analysis. A component of this problem is that a video may be reanalyzed that has already been analyzed. Identifying duplicate video sequences is difficult due to differences in videos of varying quality and size. This research uses a kd-tree structure to increase image matching speed. Keypoints are generated and added to a kd-tree of a large dimensionality (128 dimensions). All of the keypoints for the set of images are used to construct a global kd-tree, which allows nearest neighbor …

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Code White: A Signed Code Protection Mechanism For Smartphones, Joseph M. Hinson Iv Sep 2010

Code White: A Signed Code Protection Mechanism For Smartphones, Joseph M. Hinson Iv

Theses and Dissertations

This research develops Code White, a hardware-implemented trusted execution mechanism for the Symbian mobile operating system. Code White combines a signed whitelist approach with the execution prevention technology offered by the ARM architecture. Testing shows that it prevents all untrusted user applications from executing while allowing all trusted applications to load and run. Performance testing in contrast with an unmodified Symbian system shows that the difference in load time increases linearly as the application file size increases. The predicted load time for an application with a one megabyte code section remains well below one second, ensuring uninterrupted experience for the …

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Accelerating Malware Detection Via A Graphics Processing Unit, Nicholas S. Kovach Sep 2010

Accelerating Malware Detection Via A Graphics Processing Unit, Nicholas S. Kovach

Theses and Dissertations

Real-time malware analysis requires processing large amounts of data storage to look for suspicious files. This is a time consuming process that (requires a large amount of processing power) often affecting other applications running on a personal computer. This research investigates the viability of using Graphic Processing Units (GPUs), present in many personal computers, to distribute the workload normally processed by the standard Central Processing Unit (CPU). Three experiments are conducted using an industry standard GPU, the NVIDIA GeForce 9500 GT card. The goal of the first experiment is to find the optimal number of threads per block for calculating …

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Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard Sep 2010

Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard

Theses and Dissertations

As malware has evolved over the years, it has gone from harmless programs that copy themselves into other executables to modern day botnets that perform bank fraud and identity theft. Modern malware often has a need to communicate back to the author, or other machines that are also infected. Several techniques for transmitting this data covertly have been developed over the years which vary significantly in their level of sophistication. This research creates a new covert channel technique for stealing information from a network by piggybacking on user-generated network traffic. Specifically, steganography drop boxes and passive covert channels are merged …

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A Comparative Analysis Of Ascii And Xml Logging Systems, Eric C. Hanington Sep 2010

A Comparative Analysis Of Ascii And Xml Logging Systems, Eric C. Hanington

Theses and Dissertations

This research compares XML and ASCII based event logging systems in terms of their storage and processing efficiency. XML has been an emerging technology, even for security. Therefore, it is researched as a logging system with the mitigation of its verbosity. Each system consists of source content, the network transmission, database storage, and querying which are all studied as individual parts. The ASCII logging system consists of the text file as source, FTP as transport, and a relational database system for storage and querying. The XML system has the XML files and XML files in binary form using Efficient XML …

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Orbital Tori Construction Using Trajectory Following Spectral Methods, Ralph E. Bordner Iii Sep 2010

Orbital Tori Construction Using Trajectory Following Spectral Methods, Ralph E. Bordner Iii

Theses and Dissertations

By assuming the motion of a satellite about the earth’s geopotential mimics the known Kolmogorov-Arnold-Moser (KAM) solution of a lightly perturbed integrable Hamiltonian system, this research focused on applying trajectory following spectral methods to estimate orbital tori from sampled orbital data. From an estimated basis frequency set, orbital data was decomposed into multi-periodic Fourier series, essentially compressing ephemerides for long-term use. Real-world Global Positioning System (GPS) orbital tracks were decomposed and reconstructed with error from as low as few kilometers per coordinate axis over a 10-week span to tens of kilometers per coordinate axis over the same time period, depending …

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Neural Extensions To Robust Parameter Design, Bernard Jacob Loeffelholz Sep 2010

Neural Extensions To Robust Parameter Design, Bernard Jacob Loeffelholz

Theses and Dissertations

Robust parameter design (RPD) is implemented in systems in which a user wants to minimize the variance of a system response caused by uncontrollable factors while obtaining a consistent and reliable system response over time. We propose the use of artificial neural networks to compensate for highly non-linear problems that quadratic regression fails to accurately model. RPD is conducted under the assumption that the relationship between system response and controllable and uncontrollable variables does not change over time. We propose a methodology to find a new set of settings that will be robust to moderate system degradation while remaining robust …

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Providing A Theoretical Basis For Nanotoxicity Risk Analysis Departing From Traditional Physiologically-Based Pharmacokinetic (Pbpk) Modeling, Dirk P. Yamamoto Sep 2010

Providing A Theoretical Basis For Nanotoxicity Risk Analysis Departing From Traditional Physiologically-Based Pharmacokinetic (Pbpk) Modeling, Dirk P. Yamamoto

Theses and Dissertations

The same novel properties of engineered nanoparticles that make them attractive may also present unique exposure risks. But, the traditional physiologically-based pharmacokinetic (PBPK) modeling assumption of instantaneous equilibration likely does not apply to nanoparticles. This simulation-based research begins with development of a model that includes diffusion, active transport, and carrier mediated transport. An eigenvalue analysis methodology was developed to examine model behavior to focus future research. Simulations using the physicochemical properties of size, shape, surface coating, and surface charge were performed and an equation was determined which estimates area under the curve for arterial blood concentration, which is a surrogate …

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Exploring The Effects Of International Traffic In Arms Regulations Restrictions On Innovation In The U.S. Space Industrial Base, Kalliroi L. Landry Sep 2010

Exploring The Effects Of International Traffic In Arms Regulations Restrictions On Innovation In The U.S. Space Industrial Base, Kalliroi L. Landry

Theses and Dissertations

The International Traffic in Arms Regulations (ITAR) are used to protect United States (U.S.) military technologies. However, changes to ITAR export controls regarding space technologies have had a major impact to the U.S. space industry. The literature mentions a concern for the health of lower-tier firms because they are a major source of innovation, but there is no additional information considering the effects of ITAR on space innovation at those lower tiers. The purpose of this thesis was to explore the implications of continuing the current ITAR restrictions with regard to innovation in the space industry. This research used a …

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Consistency Properties For Growth Model Parameters Under An Infill Asymptotics Domain, David T. Mills Sep 2010

Consistency Properties For Growth Model Parameters Under An Infill Asymptotics Domain, David T. Mills

Theses and Dissertations

Growth curves are used to model various processes, and are often seen in biological and agricultural studies. Underlying assumptions of many studies are that the process may be sampled forever, and that samples are statistically independent. We instead consider the case where sampling occurs in a finite domain, so that increased sampling forces samples closer together, and also assume a distance-based covariance function. We first prove that, under certain conditions, the mean parameter of a fixed-mean model cannot be estimated within a finite domain. We then numerically consider more complex growth curves, examining sample sizes, sample spacing, and quality of …

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Laser Demonstration And Performance Characterization Of An Optically Pumped Alkali Laser System, Clifford V. Sulham Sep 2010

Laser Demonstration And Performance Characterization Of An Optically Pumped Alkali Laser System, Clifford V. Sulham

Theses and Dissertations

Diode Pumped Alkali Lasers (DPALs) offer a promising approach for high power lasers in military applications that will not suffer from the long logistical trails of chemical lasers or the thermal management issues of diode pumped solid state lasers. This research focuses on characterizing a DPAL-type system to gain a better understanding of using this type of laser as a directed energy weapon. A rubidium laser operating at 795 nm is optically pumped by a pulsed titanium sapphire laser to investigate the dynamics of DPALs at pump intensities between 1.3 and 45 kW/cm2. Linear scaling as high as …

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Collisional Dynamics Of The Cesium D1 And D2 Transitions, Greg A. Pitz Sep 2010

Collisional Dynamics Of The Cesium D1 And D2 Transitions, Greg A. Pitz

Theses and Dissertations

The collisional dynamics of the 62P levels in cesium have been studied utilizing steady state laser absorption and laser induced florescence techniques. In addition the production of a blue beam produced by two photon absorption has been observed in potassium. The collisional broadening rate for cesium, λL, for He, Ne, Ar, Kr, Xe, N2, H2, HD, D2, CH4, C2H6, CF4, and 3He are 24.13, 10.85, 18.31, 17.82, 19.74, 16.64, 20.81, 20.06, 18.04, 29.00, 26.70, 18.84, and 26.00 MHz/torr, respectively for the …

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Effect Of Air On Vibration Of Structures, Tong Xia Sep 2010

Effect Of Air On Vibration Of Structures, Tong Xia

Civil Engineering ETDs

This research primarily studies the effect of air on vibration of structures. Theoretical solutions based on various physics are derived and compared with experimental results to determine how air modifies the vibrational behavior of structures. This work may help in determining the characteristics of structural vibrations — from acoustic behavior to earthquake response - in practical buildings. The work consists of several primary components: derivation of theories that predict the effect of air on structural vibrations and vice-versa, design of experiments, and determination of the importance of air in structural vibrations and the applicability of different physics under various vibrational …

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Improving The Quality Of Service And Security Of Military Networks With A Network Tasking Order Process, Matthew D. Compton Sep 2010

Improving The Quality Of Service And Security Of Military Networks With A Network Tasking Order Process, Matthew D. Compton

Theses and Dissertations

This research presents a Network Tasking Order process that collects mission plans, network capabilities, and historical records to build a Network Tasking Order (NTO). The NTO document directs the form and usage of the network, much like an Air Tasking Order (ATO) directs the usage of air power. The NTO process is fleshed out with the content and format of the NTO given herein for the first time. Tools such as topology control algorithms are then shown through simulation to improve the quality of service of the network by finding favorable ways to connect the assets identified during the NTO …

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Structural Assesment Of Joints In Satellites Using Guided Waves, Angela Montoya Sep 2010

Structural Assesment Of Joints In Satellites Using Guided Waves, Angela Montoya

Civil Engineering ETDs

The intention of the Air Forces Responsive Space Initiative Project is to develop procedures and technologies necessary to produce a satellite within six days from the initial order. Modular satellite designs have been proposed to help streamline the process of preparing a satellite for deployment. These designs would save time by allowing panels with common functions to be manufactured and tested long before a new satellite is needed. Prior to launch, the integrity of the panel-to-panel connections would need to be tested for quality in order to show that the craft is flight worthy. The experimental test method presented in …

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Brokering Mathematics Reform: How Principals In Predominantly Hispanic-Serving Schools Conceive Of Their Leadership Roles In The Implementation Of A District-Wide Mathematics Reform Initiative, Barbara Trujillo Sep 2010

Brokering Mathematics Reform: How Principals In Predominantly Hispanic-Serving Schools Conceive Of Their Leadership Roles In The Implementation Of A District-Wide Mathematics Reform Initiative, Barbara Trujillo

Teacher Education, Educational Leadership & Policy ETDs

Mathematics reform efforts have been of interest to educational researchers for many years, particularly since the first Curriculum and Standards for School Mathematics over twenty years ago. Yet, despite efforts to improve the teaching and learning of mathematics for all students, many students, particularly poor and minority students, still do not have access to instructional practices that allow them opportunities to learn important mathematics. Researchers have called this a problem of scale (Cobb & Smith, 2008), and have begun to consider the important role of the principal in scaling up the reforms. This qualitative cross-case study investigated the conceptions of …

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Contact Homology Of Toric Contact Manifolds Of Reeb Type, Justin Pati Sep 2010

Contact Homology Of Toric Contact Manifolds Of Reeb Type, Justin Pati

Mathematics & Statistics ETDs

We use contact homology to distinguish contact structures on various manifolds. We are primarily interested in contact manifolds which admit an action of Reeb type of a compact Lie group. In such situations it is well known that the contact manifold is then a circle orbi-bundle over a symplectic orbifold. With some extra conditions we are able to compute an invariant, cylindrical contact homology, of the contact structure in terms of some orbifold data, and the first Chern class of the tangent bundle of the base space. When these manifolds are obtained by contact reduction, then the grading of contact …

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Generalizations Of The Statistical Flowgraph Model Framework, Richard Warr Sep 2010

Generalizations Of The Statistical Flowgraph Model Framework, Richard Warr

Mathematics & Statistics ETDs

Statistical flowgraphs model multistate semi-Markov processes and provide a way to perform inference for these processes. This methodology provides powerful results that significantly impact the study of multistate semi-Markov processes. This dissertation extends previous work in several ways. First, by demonstrating how any "smooth" transition distribution can be incorporated into a statistical flowgraph model (SFGM), we provide a method to use popular distributions, such as the lognormal, that have not been used in the past. Next, we propose an alternate way to consider Bayesian SFGMs by showing how computation can be accomplished when the traditional methods of SFGMs fail to …

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Longitudinal Penalized Functional Regression, Jeff Goldsmith, Ciprian M. Crainiceanu, Brian Caffo, Daniel Reich Sep 2010

Longitudinal Penalized Functional Regression, Jeff Goldsmith, Ciprian M. Crainiceanu, Brian Caffo, Daniel Reich

Johns Hopkins University, Dept. of Biostatistics Working Papers

We propose a new regression model and inferential tools for the case when both the outcome and the functional exposures are observed at multiple visits. This data structure is new but increasingly present in applications where functions or images are recorded at multiple times. This raises new inferential challenges that cannot be addressed with current methods and software. Our proposed model generalizes the Generalized Linear Mixed Effects Model (GLMM) by adding functional predictors. Smoothness of the functional coefficients is ensured using roughness penalties estimated by Restricted Maximum Likelihood (REML) in a corresponding mixed effects model. This method is computationally feasible …

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My Point Of View, Michael L. Nelson Sep 2010

My Point Of View, Michael L. Nelson

Computer Science Presentations

PDF of a powerpoint presentation from the Web Archiving Cooperative (WAC) Meeting, Stanford University, September 9, 2010. Also available on Slideshare.

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The Setonian, September 9, 2010, Seton Hall University Sep 2010

The Setonian, September 9, 2010, Seton Hall University

2010

No abstract provided.

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Unh Receives $1m+ To Prepare Math, Science Teachers For High-Need Schools, Beth Potier Sep 2010

Unh Receives $1m+ To Prepare Math, Science Teachers For High-Need Schools, Beth Potier

Media Relations

No abstract provided.

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Western News, Sept. 9, 2010, Western Michigan University Sep 2010

Western News, Sept. 9, 2010, Western Michigan University

Western News (1972-2018)

Story highlights: Convocation to feature State of University address, campuswide awards; WMU on magazine's new top-tier list; On Campus with Cara LaLumia-Barnes.

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Testing Photons' Bose-Einstein Statistics With Compton Scattering, Brett David Altschul Sep 2010

Testing Photons' Bose-Einstein Statistics With Compton Scattering, Brett David Altschul

Faculty Publications

It is an empirical question whether photons always obey Bose-Einstein statistics, but devising and interpreting experimental tests of photon statistics can be a challenge. The nonrelativistic cross section for Compton scattering illustrates how a small admixture ν of wrong-sign statistics leads to a loss of gauge invariance; there is a large anomalous amplitude for scattering timelike photons. Nevertheless, one can interpret the observed transparency of the solar wind plasma at low frequencies as a bound ν<10−25 if Lorentz symmetry is required. If there is instead a universal preferred frame, the bound is ν<10−14, still strong compared with …

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Hawks' Herald -- September 9, 2010, Roger Williams University Sep 2010

Hawks' Herald -- September 9, 2010, Roger Williams University

Hawk's Herald

No abstract provided.

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First Search For Gravitational Waves From The Youngest Known Neutron Star, Duncan Brown, J. Abadie Sep 2010

First Search For Gravitational Waves From The Youngest Known Neutron Star, Duncan Brown, J. Abadie

Physics - All Scholarship

We present a search for periodic gravitational waves from the neutron star in the supernova remnant Cassiopeia A. The search coherently analyzes data in a 12-day interval taken from the fifth science run of the Laser Interferometer Gravitational-Wave Observatory. It searches gravitational wave frequencies from 100 to 300 Hz, and covers a wide range of first and second frequency derivatives appropriate for the age of the remnant and for different spin-down mechanisms. No gravitational wave signal was detected. Within the range of search frequencies, we set 95% confidence upper limits of 0.7--1.2e-24 on the intrinsic gravitational wave strain, 0.4--4e-4 on …

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