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2010

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Full-Text Articles in Physical Sciences and Mathematics

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 …


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 …


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 …


Reputation-Based Internet Protocol Security: A Multilayer Security Framework For Mobil Ad Hoc Networks, Timothy H. Lacey Sep 2010

Reputation-Based Internet Protocol Security: A Multilayer Security Framework For Mobil Ad Hoc Networks, Timothy H. Lacey

Theses and Dissertations

This research effort examines the theory, application, and results for a Reputation-based Internet Protocol Security (RIPSec) framework that provides security for an ad-hoc network operating in a hostile environment. In RIPSec, protection from external threats is provided in the form of encrypted communication links and encryption-wrapped nodes while internal threats are mitigated by behavior grading that assigns reputations to nodes based on their demonstrated participation in the routing process. Network availability is provided by behavior grading and round-robin multipath routing. If a node behaves faithfully, it earns a positive reputation over time. If a node misbehaves (for any number of …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


Collaborative Research: St. Elias Erosion/Tectonics Project (Steep), Peter O. Koons Sep 2010

Collaborative Research: St. Elias Erosion/Tectonics Project (Steep), Peter O. Koons

University of Maine Office of Research Administration: Grant Reports

This is a multi-disciplinary study to address the evolution of the highest coastal mountain range on Earth - the St. Elias Mountains of southern Alaska and northwestern Canada. This orogen has developed over the past few million years as the Yakutat block, a continental-oceanic terrane, has attempted subduction beneath the eastern end of the Aleutian arc-trench system. The ~500 km-long, 150 km-wide St. Elias mountain range is the product of the dynamic balance between rapid uplift induced by crustal convergence and rapid exhumation by a regional system of large, fast-moving temperate glaciers. Most sediments are deposited either on a broad …


Silver Nanosphere Sers Probes For Sensitive Identification Of Pathogens, Kyuwan Lee Sep 2010

Silver Nanosphere Sers Probes For Sensitive Identification Of Pathogens, Kyuwan Lee

Kyuwan Lee

The identification and timely detection of pathogenic bacteria is critical to ensuring safe food, health, and water. Although surface enhanced Raman scattering (SERS) methods have been used for pathogen characterization and single molecule sensing, the challenge of detecting pathogens in very low numbers using an optimal substrate that is sensitive and reproducible is still a challenge. In this report, we have developed and explored a novel SERS active substrate of 60−80 nm diameter through the assembly of Ag nanocrystals (AgNCs) into Ag nanospheres (AgNSs). A finite difference time domain (FDTD) analysis of the electromagnetic field produced by these structures and …


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 …


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 …


The Effect Of Allowing Pollution Offsets With Imperfect Enforcement, Hilary A. Sigman, Howard F. Chang Sep 2010

The Effect Of Allowing Pollution Offsets With Imperfect Enforcement, Hilary A. Sigman, Howard F. Chang

All Faculty Scholarship

Several pollution control regimes, including climate change policies, allow polluters in one sector subject to an emissions cap to offset excessive emissions in that sector with pollution abatement in another sector. The government may often find it more costly to verify offset claims than to verify compliance with emissions caps, and concerns about difficulties in enforcement may lead regulators to restrict the use of offsets. In this paper, we demonstrate that allowing offsets may increase pollution abatement and reduce illegal pollution, even if the government has a fixed enforcement budget. We explore the circumstances that may make it preferable to …


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.


Research Data: Who Will Share What, With Whom, When, And Why?, Christine L. Borgman Sep 2010

Research Data: Who Will Share What, With Whom, When, And Why?, Christine L. Borgman

Christine L. Borgman

The deluge of scientific research data has excited the general public, as well as the scientific community, with the possibilities for better understanding of scientific problems, from climate to culture. For data to be available, researchers must be willing and able to share them. The policies of governments, funding agencies, journals, and university tenure and promotion committees also influence how, when, and whether research data are shared. Data are complex objects. Their purposes and the methods by which they are produced vary widely across scientific fields, as do the criteria for sharing them. To address these challenges, it is necessary …


History Of Communication And Its Application In Multicultaral,Multilingual Social System In India Across Ages, Ratnesh Dwivedi Mr Sep 2010

History Of Communication And Its Application In Multicultaral,Multilingual Social System In India Across Ages, Ratnesh Dwivedi Mr

Ratnesh Dwivedi

The history of communication dates back to the earliest signs of cavemen.Communication can range from very subtle processes of exchange, to full conversations and mass communication. Human communication was revolutionized with speech perhaps 200,000 years ago, Symbols were developed about 30,000 years ago and writing about 7,000. On a much shorter scale, there have been major developments in the field of telecommunication in the past few centuries.


A Short Nuclear Primer, James Conca Sep 2010

A Short Nuclear Primer, James Conca

UNLV Clean Energy Forum

The 2010 UNLV Clean Energy Forum will take place on the UNLV campus September 8th. The event focuses on clean energy production in Nevada, the US Southwest, and clean research projects nationwide. Subject matter will focus on financing, national policy, current technologies, and nuclear energy.


Unlv Clean Energy Forum 2010 Agenda, University Of Nevada, Las Vegas Sep 2010

Unlv Clean Energy Forum 2010 Agenda, University Of Nevada, Las Vegas

UNLV Clean Energy Forum

The 2010 UNLV Clean Energy Forum will take place on the UNLV campus September 8th. The event focuses on clean energy production in Nevada, the US Southwest, and clean research projects nationwide. Subject matter will focus on financing, national policy, current technologies, and nuclear energy.


Unlv Clean Energy Forum 2010 Summary, University Of Nevada, Las Vegas Sep 2010

Unlv Clean Energy Forum 2010 Summary, University Of Nevada, Las Vegas

UNLV Clean Energy Forum

The 2010 UNLV Clean Energy Forum will take place on the UNLV campus September 8th. The event focuses on clean energy production in Nevada, the US Southwest, and clean research projects nationwide. Subject matter will focus on financing, national policy, current technologies, and nuclear energy.


On Two-Stage Hypothesis Testing Procedures Via Asymptotically Independent Statistics, James Dai, Charles Kooperberg, Michael L. Leblanc, Ross Prentice Sep 2010

On Two-Stage Hypothesis Testing Procedures Via Asymptotically Independent Statistics, James Dai, Charles Kooperberg, Michael L. Leblanc, Ross Prentice

UW Biostatistics Working Paper Series

Kooperberg and LeBlanc (2008) proposed a two-stage testing procedure to screen for significant interactions in genome-wide association (GWA) studies by a soft threshold on marginal associations (MA), though its theoretical properties and generalization have not been elaborated. In this article, we discuss conditions that are required to achieve strong control of the Family-Wise Error Rate (FWER) by such procedures for low or high-dimensional hypothesis testing. We provide proof of asymptotic independence of marginal association statistics and interaction statistics in linear regression, logistic regression, and Cox proportional hazard models in a randomized clinical trial (RCT) with a rare event. In case-control …


Compactons In Nonlinear Schrödinger Lattices With Strong Nonlinearity Management, F. Kh. Abdullaev, Panos Kevrekidis, M. Salerno Sep 2010

Compactons In Nonlinear Schrödinger Lattices With Strong Nonlinearity Management, F. Kh. Abdullaev, Panos Kevrekidis, M. Salerno

Panos Kevrekidis

The existence of compactons in the discrete nonlinear Schr\"odinger equation in the presence of fast periodic time modulations of the nonlinearity is demonstrated. In the averaged DNLS equation the resulting effective inter-well tunneling depends on modulation parameters {\it and} on the field amplitude. This introduces nonlinear dispersion in the system and can lead to a prototypical realization of single- or multi-site stable discrete compactons in nonlinear optical waveguide and BEC arrays. These structures can dynamically arise out of Gaussian or compactly supported initial data.


2010 National Clean Energy Summit 3.0: Program Agenda, University Of Nevada Las Vegas, Center For American Progress Action Fund Sep 2010

2010 National Clean Energy Summit 3.0: Program Agenda, University Of Nevada Las Vegas, Center For American Progress Action Fund

National Clean Energy Summit

High-level industry leaders, policy experts, investors, and public officials, along with citizens and the media, will gather in Nevada for a day-long summit hosted by the Center for American Progress Action Fund, Senate Majority Leader Harry Reid (D-NV), and the University of Nevada, Las Vegas. National Clean Energy Summit 3.0: Investing in American Jobs, the third annual summit, will bring together top minds to chart the course for our nation’s clean energy future.


Predictions For The Rates Of Compact Binary Coalescences Observable By Ground-Based Gravitational-Wave Detectors, J. Abadie, B. P. Abbott, R. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, R. Adhikari, P. Ajith, B. Allen, G. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W. G. Anderson, F. Antonucci, S. Aoudia, M. A. Arain, M. Araya, M. Aronsson, K. G. Arun, Y. Aso, S. Aston, P. Astone, D. E. Atkinson, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, G. Ballardin, Shaon Ghosh Sep 2010

Predictions For The Rates Of Compact Binary Coalescences Observable By Ground-Based Gravitational-Wave Detectors, J. Abadie, B. P. Abbott, R. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, R. Adhikari, P. Ajith, B. Allen, G. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W. G. Anderson, F. Antonucci, S. Aoudia, M. A. Arain, M. Araya, M. Aronsson, K. G. Arun, Y. Aso, S. Aston, P. Astone, D. E. Atkinson, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, G. Ballardin, Shaon Ghosh

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present an up-to-date, comprehensive summary of the rates for all types of compact binary coalescence sources detectable by the initial and advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo. Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters and are still uncertain. Themost confident among these estimates are the rate predictions for coalescing binary neutron stars which are based on extrapolations from observed binary pulsars in our galaxy. These yield a likely coalescence rate of 100 Myr-1 per MilkyWay Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 …


Stratifying Subjects For Treatment Selection With Censored Event Time Data From A Comparative Study, Lihui Zhao, Tianxi Cai, Lu Tian, Hajime Uno, Scott D. Solomon, L. J. Wei Sep 2010

Stratifying Subjects For Treatment Selection With Censored Event Time Data From A Comparative Study, Lihui Zhao, Tianxi Cai, Lu Tian, Hajime Uno, Scott D. Solomon, L. J. Wei

Harvard University Biostatistics Working Paper Series

No abstract provided.


Environmental Disturbance Of Oligotrophic Bacteria And Effects On Water Quality In Deep Karstic Pools, Andrea Hunter Sep 2010

Environmental Disturbance Of Oligotrophic Bacteria And Effects On Water Quality In Deep Karstic Pools, Andrea Hunter

Water Resources Professional Project Reports

Active intervention of humans in pristine water resource environments has caused both surface and ground waters to degrade in quality and natural purification capacity (Geldreich 1996). Groundwater is often considered to be less impacted than that of surface water due to the absence of climate changes and storm water migrations (Geldreich 1996). Shallow karstic limestone areas (less than 30 m deep) have a greater change of surface contamination since surface water runoff can rapidly percolate through areas lacking a protective bedrock layer.


2010 Fall Engr333 Project Assignment, Matthew K. Heun Sep 2010

2010 Fall Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Fall 2010 ENGR333 project focused on heating and air-conditioning in campus dormitories, which are notoriously leaky and inefficient.

I asked the students “What would it take to retrofit the Bolt-Heyns-Timmer (BHT) dormitory heating and air-conditioning systems in a manner that achieves LEED certification?”

Customer

The customer for this project was Calvin’s VP for finance Henry DeVries.


Predictions For The Rates Of Compact Binary Coalescences Observable By Ground-Based Gravitational-Wave Detectors, J. Abadie, B. P. Abbott, R. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, R. Adhikari, P. Ajith, B. Allen, G. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W. G. Anderson, F. Antonucci, S. Aoudia, M. A. Arain, M. Araya, M. Aronsson, K. G. Arun, Y. Aso, S. Aston, P. Astone, D. E. Atkinson, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, G. Ballardin, S. Ballmer, Tiffany Z. Summerscales Sep 2010

Predictions For The Rates Of Compact Binary Coalescences Observable By Ground-Based Gravitational-Wave Detectors, J. Abadie, B. P. Abbott, R. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, R. Adhikari, P. Ajith, B. Allen, G. Allen, E. Amador Ceron, R. S. Amin, S. B. Anderson, W. G. Anderson, F. Antonucci, S. Aoudia, M. A. Arain, M. Araya, M. Aronsson, K. G. Arun, Y. Aso, S. Aston, P. Astone, D. E. Atkinson, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, G. Ballardin, S. Ballmer, Tiffany Z. Summerscales

Faculty Publications

We present an up-to-date, comprehensive summary of the rates for all types of compact binary coalescence sources detectable by the initial and advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo. Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters and are still uncertain. Themost confident among these estimates are the rate predictions for coalescing binary neutron stars which are based on extrapolations from observed binary pulsars in our galaxy. These yield a likely coalescence rate of 100 Myr-1 per MilkyWay Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 …