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2011

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Articles 181 - 210 of 7765

Full-Text Articles in Physical Sciences and Mathematics

Quantifying Computer Network Security, Ian Burchett Dec 2011

Quantifying Computer Network Security, Ian Burchett

Masters Theses & Specialist Projects

Simplifying network security data to the point that it is readily accessible and usable by a wider audience is increasingly becoming important, as networks become larger and security conditions and threats become more dynamic and complex, requiring a broader and more varied security staff makeup. With the need for a simple metric to quantify the security level on a network, this thesis proposes: simplify a network’s security risk level into a simple metric. Methods for this simplification of an entire network’s security level are conducted on several characteristic networks. Identification of computer network port vulnerabilities from NIST’s Network Vulnerability Database …


Developing Hybrid Approaches To Predict Pka Values Of Ionizable Groups, Shawn Witham, Kemper Talley, Lin Wang, Zhe Zhang, Daquan Gao, Wei Yang, Emil Alexov Dec 2011

Developing Hybrid Approaches To Predict Pka Values Of Ionizable Groups, Shawn Witham, Kemper Talley, Lin Wang, Zhe Zhang, Daquan Gao, Wei Yang, Emil Alexov

Publications

Accurate predictions of pKa values of titratable groups require taking into account all relevant processes associated with the ionization/deionization. Frequently, however, the ionization does not involve significant structural changes and the dominating effects are purely electrostatic in origin allowing accurate predictions to be made based on the electrostatic energy difference between ionized and neutral forms alone using a static structure. On another hand, if the change of the charge state is accompanied by a structural reorganization of the target protein, then the relevant conformational changes have to be taken into account in the pKa calculations. Here we report a hybrid …


Progress In The Prediction Of Pka Values In Proteins, Emil Alexov, Ernest L. Mehler, Nathan Baker, Antonio Baptista, Yong Huang, Francesca Milletti, Jens Erik Nielsen, Damien Farrell, Tommy Carstensen, Mats H.M. Olsson, Jana K. Shen, Jim Warwicker, Sarah Williams, J Michael Word Dec 2011

Progress In The Prediction Of Pka Values In Proteins, Emil Alexov, Ernest L. Mehler, Nathan Baker, Antonio Baptista, Yong Huang, Francesca Milletti, Jens Erik Nielsen, Damien Farrell, Tommy Carstensen, Mats H.M. Olsson, Jana K. Shen, Jim Warwicker, Sarah Williams, J Michael Word

Publications

The pKa-cooperative aims to provide a forum for experimental and theoretical researchers interested in protein pKa values and protein electrostatics in general. The first round of the pKa-cooperative, which challenged computational labs to carry out blind predictions against pKas experimentally determined in the laboratory of Bertrand Garcia-Moreno, was completed and results discussed at the Telluride meeting (July 6–10, 2009). This article serves as an introduction to the reports submitted by the blind prediction participants that will be published in a special issue of PROTEINS: Structure, Function and Bioinformatics. …


Achieving Laser Wavelength Stability For Use In Neutral Atom Quantum Computing, Jennifer H. Rushing Dec 2011

Achieving Laser Wavelength Stability For Use In Neutral Atom Quantum Computing, Jennifer H. Rushing

Physics

Quantum computing may still be decades away from realization but the pieces necessary for the construction of the first quantum chip are beginning to come together. One piece still eluding researchers is the ability to address individual atoms within a scalable quantum chip structure. The resolution to this issue may be found in any one of several promising implementations, including the use of neutral atoms trapped in 2D optical lattices. One method of constructing such lattices, which has been shown to be computationally viable, employs the diffraction pattern just behind a circular aperture. Laser wavelength stability plays a crucial role …


Aerospace Section, Adrianne J. Washburn Dec 2011

Aerospace Section, Adrianne J. Washburn

Sci-Tech News

No abstract provided.


Object Recognition Based On Shape And Function, Akihiro Eguchi Dec 2011

Object Recognition Based On Shape And Function, Akihiro Eguchi

Computer Science and Computer Engineering Undergraduate Honors Theses

This thesis explores a new approach to computational object recognition by borrowing an idea from child language acquisition studies in developmental psychology. Whereas previous image recognition research used shape to recognize and label a target object, the model proposed in this thesis also uses the function of the object resulting in a more accurate recognition. This thesis makes use of new gaming technology, Microsoft’s Kinect, in implementing the proposed new object recognition model. A demonstration of the model developed in this project properly infers different names for similarly shaped objects and the same name for differently shaped objects.


Land Systems Of The Kimberley Region, Western Australia, A L. Payne, N Schoknecht Dec 2011

Land Systems Of The Kimberley Region, Western Australia, A L. Payne, N Schoknecht

Technical Bulletins

The Land Systems of the Kimberley Region Report describes and maps the landscapes, soils and vegetation of the Kimberley region. This report is a consolidation of surveys carried out by different organisations, across different areas of the Kimberley, since the 1940s. The Kimberley region, as defined in this bulletin, covers 330 070km². The report categorises the Kimberley region into 111 land systems. Under each land system, the report identifies the vulnerabilities of those areas, and provides recommendations on how to achieve sustainable use. The report also publishes pasture types for the entire region and the grazing potential for each pasture, …


Groundwater Chemistry Of The Weaber Plain: Preliminary Results, Adam Lillicrap, Paul Raper, Richard J. George Dr, D L. Bennett Dec 2011

Groundwater Chemistry Of The Weaber Plain: Preliminary Results, Adam Lillicrap, Paul Raper, Richard J. George Dr, D L. Bennett

Resource management technical reports

In 2008, the Ord Irrigation Expansion Project was approved by the Western Australian Government to develop irrigated agriculture on the Weaber Plain. Construction of the M2 supply channel connecting the ORIA and the Weaber Plain, and the final period of irrigation design, environmental management and related approval processes, commenced later in 2009. This process followed a protracted period of public and private industry planning and environmental assessment (Kinhill 2000). This report summarises an analysis of groundwater salinity trends on the Ivanhoe and Weaber plains and the preliminary results of an intensive water-quality sampling program carried out in 2010 as part …


Spatial Analysis Of Fatal Automobile Crashes In Kentucky, William Nathan Oris Dec 2011

Spatial Analysis Of Fatal Automobile Crashes In Kentucky, William Nathan Oris

Masters Theses & Specialist Projects

Fatal automobile crashes have claimed the lives of over 33,000 people each year in the United States since 1995. As in any point event, fatal crash events do not occur randomly in time or space. The objectives of this study were to identify spatial patterns and hot spots in FARS (Fatal Analysis Reporting System) fatal crash events based on temporal and demographic characteristics. The methods employed included 1) rate calculation using FARS points and average daily traffic flow; 2) planar kernel density estimation of FARS crash events based on temporal and demographic attributes within the data; and 3) two case …


Distribution Of Trace Elements In Cumberland River Basin Reservoir Sediments, Laura Mahoney Benneyworth Dec 2011

Distribution Of Trace Elements In Cumberland River Basin Reservoir Sediments, Laura Mahoney Benneyworth

Masters Theses & Specialist Projects

The U.S. Army Corps of Engineers, Nashville District, maintains ten reservoirs in the Cumberland River Basin in Kentucky and Tennessee, and has been monitoring sediment chemistry in the reservoirs since 1994. The purpose of this study is to evaluate the sediment data collected from the reservoirs from 1994 to 2010 to determine if there are any spatial patterns of the trace elements: arsenic, beryllium, cadmium, chromium, copper, lead, mercury, nickel, and zinc. The results indicated that trace element levels were consistent with national baseline concentrations measured by the U.S. Geological Survey. Center Hill reservoir had the greatest number of trace …


Multiple Storm Event Impacts On Epikarst Storage And Transport Of Organic Soil Amendments In South-Central Kentucky, Sean M. Vanderhoff Dec 2011

Multiple Storm Event Impacts On Epikarst Storage And Transport Of Organic Soil Amendments In South-Central Kentucky, Sean M. Vanderhoff

Masters Theses & Specialist Projects

The groundwater in agricultural karst areas is susceptible to contamination from organic soil amendments and pesticides. During major storm events during 2011, dye traces were initiated using sulphorhodamine-B, fluorescein and eosine in a groundwater recharge area where manure was applied to the ground. Fecal coliform samples were collected from significant storm events from January-September 2011. Water samples and geochemical data were collected every four hours before, during, and between the storm events from a waterfall in Crumps cave flowing from the known recharge area to track the transport and residence time of the epikarst water and organic soil amendments during …


Sensitivity Of The Frozen/Melted Basal Boundary To Perturbations Of Basal Traction And Geothermal Heat Flux : Isunnguata Sermia, Western Greenland, Douglas John Brinkerhoff, Toby Warren Meierbachtol, Jesse Johnson, Joel T. Harper Dec 2011

Sensitivity Of The Frozen/Melted Basal Boundary To Perturbations Of Basal Traction And Geothermal Heat Flux : Isunnguata Sermia, Western Greenland, Douglas John Brinkerhoff, Toby Warren Meierbachtol, Jesse Johnson, Joel T. Harper

Computer Science Faculty Publications

A full-stress, thermomechanically coupled, numerical model is used to explore the interaction between basal thermal conditions and motion of a terrestrially terminating section of the west Greenland ice sheet. The model domain is a two-dimensional flowline profile extending from the ice divide to the margin. We use data-assimilation techniques based on the adjoint model in order to optimize the basal traction field, minimizing the difference between modeled and observed surface velocities. We monitor the sensitivity of the frozen/melted boundary (FMB) to changes in prescribed geothermal heat flux and sliding speed by applying perturbations to each of these parameters. The FMB …


Modeling 5 Years Of Subglacial Lake Activity In The Macayeal Ice Stream (Antarctica) Catchment Through Assimilation Of Icesat Laser Altimetry, Sasha P. Carter, Helen A. Fricker, Donald D. Blankenship, Jesse V. Johnson, William Lipscomb, Stephen F. Price, Duncan A. Young Dec 2011

Modeling 5 Years Of Subglacial Lake Activity In The Macayeal Ice Stream (Antarctica) Catchment Through Assimilation Of Icesat Laser Altimetry, Sasha P. Carter, Helen A. Fricker, Donald D. Blankenship, Jesse V. Johnson, William Lipscomb, Stephen F. Price, Duncan A. Young

Computer Science Faculty Publications

Subglacial lakes beneath Antarctica’s fast-moving ice streams are known to undergo ~1km3 volume changes on annual timescales. Focusing on the MacAyeal Ice Stream (MacIS) lake system, we create a simple model for the response of subglacial water distribution to lake discharge events through assimilation of lake volume changes estimated from Ice, Cloud and land Elevation Satellite (ICESat) laser altimetry. We construct a steady-state water transport model in which known subglacial lakes are treated as either sinks or sources depending on the ICESat-derived filling or drainingrates. The modeled volume change rates of five large subglacial lakes in the downstream portion …


Fast Super-Resolution With Affine Motion Using An Adaptive Wiener Filter And Its Application To Airborne Imaging, Russell C. Hardie, Kenneth J. Barnard, Raúl Ordóñez Dec 2011

Fast Super-Resolution With Affine Motion Using An Adaptive Wiener Filter And Its Application To Airborne Imaging, Russell C. Hardie, Kenneth J. Barnard, Raúl Ordóñez

Electrical and Computer Engineering Faculty Publications

Fast nonuniform interpolation based super-resolution (SR) has traditionally been limited to applications with translational interframe motion. This is in part because such methods are based on an underlying assumption that the warping and blurring components in the observation model commute. For translational motion this is the case, but it is not true in general. This presents a problem for applications such as airborne imaging where translation may be insufficient. Here we present a new Fourier domain analysis to show that, for many image systems, an affine warping model with limited zoom and shear approximately commutes with the point spread function …


Personality Dimensions And Temperaments Of Engineering Professors And Students – A Survey, Arif Raza, Zaka Ulmustafa, Luiz Fernando Capretz Dec 2011

Personality Dimensions And Temperaments Of Engineering Professors And Students – A Survey, Arif Raza, Zaka Ulmustafa, Luiz Fernando Capretz

Electrical and Computer Engineering Publications

This research work aims to study personality profiles and temperaments of Pakistani software engineering professors and students. In this survey we have collected personality profiles of 18 professors and 92 software engineering students. According to the Myers-Briggs Type Indicator (MBTI) instrument, the most prominent personality type among professors as well as among students is a combination of Introversion, Sensing, Thinking, and Judging (ISTJ). The study shows ITs (Introverts and Thinking) and IJs (Introverts and Judging) are the leading temperaments among the professors. About the students’ data, the results of the study indicate SJs (Sensing and Judging) and ISs (Introverts and …


Dynamic Server Allocation At Parallel Queues, Susan E. Martonosi Dec 2011

Dynamic Server Allocation At Parallel Queues, Susan E. Martonosi

All HMC Faculty Publications and Research

We explore whether dynamically reassigning servers to parallel queues in response to queue imbalances can reduce average waiting time in those queues. We use approximate dynamic programming methods to determine when servers should be switched, and we compare the performance of such dynamic allocations to that of a pre-scheduled deterministic allocation. Testing our method on both synthetic data and data from airport security checkpoints at Boston Logan International Airport, we find that in situations where the uncertainty in customer arrival rates is significant, dynamically reallocating servers can substantially reduce waiting time. Moreover, we find that intuitive switching strategies that are …


The R Journal (December 2011) 3(2): Complete Issue, The R Foundation Dec 2011

The R Journal (December 2011) 3(2): Complete Issue, The R Foundation

The R Journal

Contributed Research Articles

Creating and Deploying an Application with (R)Excel and R, Thomas Baier, Erich Neuwirth, and Michele De Meo

glm2: Fitting Generalized Linear Models with Convergence Problems, Ian C. Marschner

Implementing the Compendium Concept with Sweave and DOCSTRIP, Michael Lundholm

Watch Your Spelling! Kurt Hornik and Duncan Murdoch

Ckmeans.1d.dp: Optimal k-means Clustering in One Dimension by Dynamic Programming, Haizhou Wang and Mingzhou Song

Nonparametric Goodness-of-Fit Tests for Discrete Null Distributions, Taylor B. Arnold and John W. Emerson

Using the Google Visualisation API with R, Markus Gesmann and Diego de Castillo

GrapheR: a Multiplatform GUI for Drawing Customizable Graphs in …


Three-Dimensionally Preserved Integument Reveals Hydrodynamic Adaptations In The Extinct Marine Lizard Ectenosaurus (Reptilia, Mosasauridae), Johan Lindgren, Michael J. Everhart, Michael W. Caldwell Dec 2011

Three-Dimensionally Preserved Integument Reveals Hydrodynamic Adaptations In The Extinct Marine Lizard Ectenosaurus (Reptilia, Mosasauridae), Johan Lindgren, Michael J. Everhart, Michael W. Caldwell

Sternberg Museum of Natural History Faculty Publications

The physical properties of water and the environment it presents to its inhabitants provide stringent constraints and selection pressures affecting aquatic adaptation and evolution. Mosasaurs (a group of secondarily aquatic reptiles that occupied a broad array of predatory niches in the Cretaceous marine ecosystems about 98-65 million years ago) have traditionally been considered as anguilliform locomotors capable only of generating short bursts of speed during brief ambush pursuits. Here we report on an exceptionally preserved, long-snouted mosasaur (Ectenosaurus clidastoides) from the Santonian (Upper Cretaceous) part of the Smoky Hill Chalk Member of the Niobrara Formation in western Kansas, USA, that …


Perception Of Aquifer Depletion And The Effects Of Land Use Change Across The Madaba Plain, Jordan, Mohammad Salem Dec 2011

Perception Of Aquifer Depletion And The Effects Of Land Use Change Across The Madaba Plain, Jordan, Mohammad Salem

Graduate Theses and Dissertations

In Jordan, demand for water for agricultural purposes has put a high strain on aquifer resources. Water mining, erosion, and desertification have all increased as global temperatures rise. This along with fragmentation of the landscape have altered the environment in a profound way. The Madaba Plain was chosen for this study due to the agricultural activities that take place there, as well as the proximity to a number of population centers. The purpose of the study is to examine how fragmentation of irrigated landscape has affected the aquifers underneath, while taking into account perceptions of risk of the local population. …


Removal Of Disinfection By-Product Precursors Using Magnetic Ion Exchange (Miex(R)): The Effects Of Ph And Source Water Variability, Sarah Cousins Dec 2011

Removal Of Disinfection By-Product Precursors Using Magnetic Ion Exchange (Miex(R)): The Effects Of Ph And Source Water Variability, Sarah Cousins

Graduate Theses and Dissertations

Disinfection by-products (DBPs) form as an unintended result of drinking water disinfection, from chemical reactions between disinfectants (e.g., free chlorine) and naturally occurring dissolved organic matter (DOM). At present, 11 DBPs are regulated in treated drinking waters due to potential adverse health effects, including four trihalomethanes (THMs). Despite nearly 40 years of DBP research, compliance with DBP regulations remains a challenge for many drinking water treatment plants (DWTPs), including the four DWTPs located on the Beaver Lake Reservoir in Northwest Arkansas. Due to the high net negative surface charge on DOM, anion exchange is one potentially viable method for removing …


Develop Energy Dashboard For Real-Time Campus Energy Use Monitoring, Hsui-Lin Winkler, Charlene Hoegler, William Batina Dec 2011

Develop Energy Dashboard For Real-Time Campus Energy Use Monitoring, Hsui-Lin Winkler, Charlene Hoegler, William Batina

Cornerstone 3 Reports : Interdisciplinary Informatics

No abstract provided.


Lithium In The Upper Centaurus Lupus And Lower Centaurus Crux Subgroups Of Scorpius-Centaurus, Eric J. Bubar, Marc Schaeuble, Jeremy R. King, Eric E. Mamajek, John R. Stauffer Dec 2011

Lithium In The Upper Centaurus Lupus And Lower Centaurus Crux Subgroups Of Scorpius-Centaurus, Eric J. Bubar, Marc Schaeuble, Jeremy R. King, Eric E. Mamajek, John R. Stauffer

Publications

We utilize spectroscopically derived model atmosphere parameters and the Li i λ6104 subordinate line and the λ6708 doublet to derive lithium abundances for 12 members of the Upper Centaurus Lupus and Lower Centaurus Crux subgroups of the Scorpius–Centaurus OB Association. The results indicate any intrinsic Li scatter in our 0.9–1.4 M stars is limited to ∼0.15 dex, consistent with the lack of dispersion in 1.0 M stars in the 100 Myr Pleiades and 30–50 Myr IC 2391 and 2602 clusters. Both ab initio uncertainty estimates and the derived abundances themselves indicate that the λ6104 line yields abundances with equivalent or …


Bi-Stability, Hysteresis, And Memory Of Voltage-Gated Lysenin Channels, Daniel Fologea, Eric Krueger, Yuriy I. Mazur, Christine Stith, Yui Okuyama, Ralph Henry, Greg J. Salamo Dec 2011

Bi-Stability, Hysteresis, And Memory Of Voltage-Gated Lysenin Channels, Daniel Fologea, Eric Krueger, Yuriy I. Mazur, Christine Stith, Yui Okuyama, Ralph Henry, Greg J. Salamo

Physics Faculty Publications and Presentations

Lysenin, a 297 amino acid pore-forming protein extracted from the coelomic fluid of the earthworm E. foetida, inserts constitutively open large conductance channels in natural and artificial lipid membranes containing sphingomyelin. The inserted channels show voltage regulation and slowly close at positive applied voltages. We report on the consequences of slow voltage-induced gating of lysenin channels inserted into a planar Bilayer Lipid Membrane (BLM), and demonstrate that these pore-forming proteins constitute memory elements that manifest gating bi-stability in response to variable external voltages. The hysteresis in macroscopic currents dynamically changes when the time scale of the voltage variation is …


Outlier Detection Using Modified-Ranks And Other Variants, Huaming Huang, Kishan Mehrotra, Chilukuri K. Mohan Dec 2011

Outlier Detection Using Modified-Ranks And Other Variants, Huaming Huang, Kishan Mehrotra, Chilukuri K. Mohan

Electrical Engineering and Computer Science - Technical Reports

Rank based algorithms provide a promising approach for outlier detection, but currently used rank-based measures of outlier detection suffer from two deficiencies: first they take a large value from an object whose density is high even though the object may not be an outlier and second the distance between the object and its nearest cluster plays a mild role though its rank with respect to its neighbor. To correct for these deficiencies we introduce the concept of modified-rank and propose new algorithms for outlier detection based on this concept.


Characterization Of Enhanced Interferometric Gravitational Wave Detectors And Studies Of Numeric Simulations For Compact-Binary Coalescences, Larne Pekowsky Dec 2011

Characterization Of Enhanced Interferometric Gravitational Wave Detectors And Studies Of Numeric Simulations For Compact-Binary Coalescences, Larne Pekowsky

Physics - Dissertations

Gravitational waves are a consequence of the general theory of relativity. Direct detection of such waves will provide a wealth of information about physics, astronomy, and cosmology. A worldwide effort is currently underway to make the first direct detection of gravitational waves. The global network of detectors includes the Laser Interferometer Gravitational-wave Observatory (LIGO), which recently completed its sixth science run.

A particularly promising source of gravitational waves is a binary system consisting of two neutron stars and/or black holes. As the objects orbit each other they emit gravitational radiation, lose energy, and spiral inwards. This produces a characteristic ``chirp'' …


Controlling Biofouling By Surface Engineering And Molecular Inhibition, Debjyoti Bandyopadhyay Dec 2011

Controlling Biofouling By Surface Engineering And Molecular Inhibition, Debjyoti Bandyopadhyay

Chemistry - Dissertations

The common theme that binds together all the chapters in this dissertation is anti-biofouling chemistry. By utilizing tools of surface engineering and molecular inhibition, a hypothesis driven, systematic approach of controlling the different forms of biofoulings such as protein adsorption, mammalian cell adhesion and biofilm formation is presented. Chapter 1 provides a brief introduction about topics relevant for understanding the studies presented in subsequent chapters. Chapter 2 reports the synthesis of enantiomerically pure alkanethiols that terminate with different stereoisomer's of sugar alcohols, and the effect of chirality of these polyol-terminated self-assembled monolayers (SAMs) on resisting protein adsorption.

Chapter 3 …


Searching For Gravitational Waves From Compact Binary Coalescence Using Ligo And Virgo Data, Collin Capano Dec 2011

Searching For Gravitational Waves From Compact Binary Coalescence Using Ligo And Virgo Data, Collin Capano

Physics - Dissertations

This thesis describes current efforts to search for gravitational waves from compact binary coalescences (CBCs) by the LIGO Scientific Collaboration (LSC) and the Virgo Collaboration. We briefly review the physics of gravitational-wave emission and detection, describing how gravitational waves are emitted from "inspiraling" compact stellar mass objects and how the LSC and Virgo try to detect them using interferometers. Next we review the data-analysis principles used to search for potential signals in the detectors' noise. These principles are employed by ``ihope," which is the data-analysis pipeline used to search for CBCs. We describe each step in this pipeline and discuss …


Benthic Habitat Characterization For The South Florida Ocean Measurement Facility (Sfomf), David S. Gilliam, Brian K. Walker Dec 2011

Benthic Habitat Characterization For The South Florida Ocean Measurement Facility (Sfomf), David S. Gilliam, Brian K. Walker

Marine & Environmental Sciences Faculty Reports

This report summarizes the distribution and relative abundance of two stony coral species (Acropora cervicornis and Acropora palmata) currently listed as threatened under the US Endangered Species Act (ESA) (Federal Register/Vol. 71, No. 129/Thursday, July 6, 2006 / Rules and Regulations, http://www.gpo.gov/fdsys/pkg/FR-2006-07-06/pdf/06-6017.pdf) and seven additional stony coral species which have been petitioned for listing as endangered or threatened under the ESA (Agaricia lamarcki, Dendrogyra cylindrus, Dichocoenia stokesii, Montastraea annularis, Montastraea faveolata, Montastraea franksi, and Mycetophyllia ferox) (Federal Register/Vol. 75, No. 27/Wednesday, February 10, 2010/Proposed Rules, http://www.nmfs.noaa.gov/pr/pdfs/fr/fr75-6616.pdf). This report also summarizes the abundance and distribution …


A Century Of Chemistry Instruction At The College In Arlington: 1895-1995 (A Memoir And Scrapbook), Thomas James Cogdell Dec 2011

A Century Of Chemistry Instruction At The College In Arlington: 1895-1995 (A Memoir And Scrapbook), Thomas James Cogdell

Chemistry & Biochemistry Faculty Publications - Archive

No abstract provided.


Full Issue, The Mcnair Team Dec 2011

Full Issue, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.