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2006

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Articles 481 - 510 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Eliminating Redundant And Less-Informative Rss News Articles Based On Word Similarity And A Fuzzy Equivalence Relation, Ian Garcia, Yiu-Kai D. Ng Nov 2006

Eliminating Redundant And Less-Informative Rss News Articles Based On Word Similarity And A Fuzzy Equivalence Relation, Ian Garcia, Yiu-Kai D. Ng

Faculty Publications

The Internet has marked this era as the information age. There is no precedent in the amazing amount of information, especially network news, that can be accessed by Internet users these days. As a result, the problem of seeking information in online news articles is not the lack of them but being overwhelmed by them. This brings huge challenges in processing online news feeds, e.g., how to determine which news article is important, how to determine the quality of each news article, and how to filter irrelevant and redundant information. In this paper, we propose a method for filtering redundant …

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The Biology Of Introduced Norway Rats On Kiska Island, Alaska, And An Evaluation Of An Eradication Approach, Gary W. Witmer, Patrick Burke, Susan Jojola, Peter Dunlevy Nov 2006

The Biology Of Introduced Norway Rats On Kiska Island, Alaska, And An Evaluation Of An Eradication Approach, Gary W. Witmer, Patrick Burke, Susan Jojola, Peter Dunlevy

United States Department of Agriculture Wildlife Services: Staff Publications

Introduced, invasive rats can cause substantial damage to native flora and fauna, including ground-nesting seabirds, when they become established on islands. We tested a control method for introduced Norway rats on Kiska Island, Alaska, during April-May, 2004, by hand-broadcasting rodenticide pellets (0.005% diaphacinone) over a 4-ha area at the rate of 28 kg/ha. We also gathered data on aspects of rat ecology and distribution, although rats were difficult to detect and capture. The rodenticide bait pellets seemed to have been effective in reducing the Norway rat population, however, this is based on a limited observation of rat sign and captures. …

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Graded Interface Models For More Accurate Determination Of Van Der Waals-London Dispersion Interactions Across Grain Boundaries, Roger H. French Nov 2006

Graded Interface Models For More Accurate Determination Of Van Der Waals-London Dispersion Interactions Across Grain Boundaries, Roger H. French

Faculty Scholarship

Attractive van der Waals–London dispersion interactions between two half crystals arise from local physical property gradients within the interface layer separating the crystals. Hamaker coefficients and London dispersion energies were quantitatively determined for Σ5 and near-∑13 grain boundaries in SrTiO3 by analysis of spatially resolved valence electron energy-loss spectroscopy (VEELS) data. From the experimental data, local complex dielectric functions were determined, from which optical properties can be locally analyzed. Both local electronic structures and optical properties revealed gradients within the grain boundary cores of both investigated interfaces. The results show that even in the presence of atomically structured grain boundary …

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Sequential Extraction Of Copper And Zinc From Two Californian Soils, Katharine Carr, Christopher Appel, Craig Stubler, Shana Mccarthy Nov 2006

Sequential Extraction Of Copper And Zinc From Two Californian Soils, Katharine Carr, Christopher Appel, Craig Stubler, Shana Mccarthy

Earth and Soil Sciences

In order to understand how to remediate soils contaminated with heavy metals, it is important to first understand their sorption mechanisms. The objective of this study was to evaluate the bioavailability of elevated levels of soil copper (Cu) and zinc (Zn) via sequential extraction. Elevated levels of Cu and Zn were added separately and concurrently to a Mollisol and an Entisol from the central coast of California. The exchangeable amount of Cu and Zn was then extracted from the sorbed amount via 0.1 M NaNO3. The residual fraction was then extracted with 0.1 M sodium citrate (NaC6 …

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Total And Bioavailable Chromium Along A Toposequence In San Luis Obispo, Ca., Britani Harris, Christopher Appel, Craig Stubler, Arwen Ross, Maribel Alvarado, Katharine Carr, Byron Clamor, Lauren Corkins, Scott Grandi-Hill, Walter Levicki, Michael Wagoner, Ryan Tappero Nov 2006

Total And Bioavailable Chromium Along A Toposequence In San Luis Obispo, Ca., Britani Harris, Christopher Appel, Craig Stubler, Arwen Ross, Maribel Alvarado, Katharine Carr, Byron Clamor, Lauren Corkins, Scott Grandi-Hill, Walter Levicki, Michael Wagoner, Ryan Tappero

Earth and Soil Sciences

The presence of large quantities of Chromium metal in soil and plants is of major concern due to its toxicity to humans. Total (USEPA 3050a) and bioavailable (USEPA 1311) levels of chromium were measured along a serpentinic Central Coast toposequence. Soil from the surface and subsurface, as well as the above ground plants of the toposequence were determined and compared to several soil chemical and physical properties using a least squares regression. The binding environments and oxidation states were found through XANES and EXAFS x-ray spectroscopies. The total and bioavailable chromium concentrations of the soil averaged 1457.1 and 1.6 mg …

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Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang Nov 2006

Modeling Heterogeneous User Churn And Local Resilience Of Unstructured P2p Networks, Zhongmei Yao, Derek Leonard, Dmitri Loguinov, Xiaoming Wang

Computer Science Faculty Publications

Previous analytical results on the resilience of unstructured P2P systems have not explicitly modeled heterogeneity of user churn (i.e., difference in online behavior) or the impact of in-degree on system resilience. To overcome these limitations, we introduce a generic model of heterogeneous user churn, derive the distribution of the various metrics observed in prior experimental studies (e.g., lifetime distribution of joining users, joint distribution of session time of alive peers, and residual lifetime of a randomly selected user), derive several closed-form results on the transient behavior of in-degree, and eventually obtain the joint in/out degree isolation probability as a simple …

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On-Line Electronic Document Collaboration And Annotation, Trev R. Harmon Nov 2006

On-Line Electronic Document Collaboration And Annotation, Trev R. Harmon

Theses and Dissertations

The Internet provides a powerful medium for communication and collaboration. The ability one has to connect and interact with web-based tools from anywhere in the world makes the Internet ideal for such tasks. However, the lack of native tools can be a hindrance when deploying collaborative initiatives, as many current projects require specialized software in order to operate. This thesis demonstrates, with the comparably recent advances in browser technology and Document Object Model (DOM) implementation, a web-based collaborative annotation system can be developed that can be accessed by a user through a standards-compliant web browser. Such a system, demonstrated to …

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Digital Receipts: A System To Detect The Compromise Of Digital Certificates, Nathaniel Allen Seeley Nov 2006

Digital Receipts: A System To Detect The Compromise Of Digital Certificates, Nathaniel Allen Seeley

Theses and Dissertations

The ease of copying digital materials creates difficulty in detecting the theft of digital certificates. Uneducated users frequently fail to protect their digital certificate keys by not encrypting them, storing them in insecure places, and using them unwisely. In addition, there is no way to prove that protocols involving certificates are completely secure. This thesis introduces a system to ameliorate these problems by detecting the compromise of digital certificates. It leverages dual logging messages sent via side channels to a trusted third party. This third party correlates these messages and automatically detects when an imposter presents a certificate based on …

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Balanced Biorthogonal Scaling Vectors Using Fractal Function Macroelements On [0,1], Bruce Kessler Nov 2006

Balanced Biorthogonal Scaling Vectors Using Fractal Function Macroelements On [0,1], Bruce Kessler

Mathematics Faculty Publications

Geronimo, Hardin, et al have previously constructed orthogonal and biorthogonal scaling vectors by extending a spline scaling vector with functions supported on $[0,1]$. Many of these constructions occurred before the concept of balanced scaling vectors was introduced. This paper will show that adding functions on $[0,1]$ is insufficient for extending spline scaling vectors to scaling vectors that are both orthogonal and balanced. We are able, however, to use this technique to extend spline scaling vectors to balanced, biorthogonal scaling vectors, and we provide two large classes of this type of scaling vector, with approximation order two and three, respectively, with …

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Collaborative Research: The Tectonothermal Evolution Of A Convergent Orogen, Scott E. Johnson Nov 2006

Collaborative Research: The Tectonothermal Evolution Of A Convergent Orogen, Scott E. Johnson

University of Maine Office of Research Administration: Grant Reports

Understanding of orogenesis and its relations to mantle convection and plate tectonics relies on integrated studies of the interrelations among processes of deformation, metamorphism and magmatism. A well preserved portion of the northern Appalachian orogen is providing an outstanding laboratory for a truly integrative study of the evolution of mid-crustal processes that strongly influence orogenesis. This project is employing structural, microstructural, petrologic and thermobarometric analyses, and chemical and isotopic dating, to temporally and spatially link deformation, metamorphism and magmatism during the progressive growth of this orogenic belt. This information is being used to set constraints and boundary conditions on coupled, …

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Gene Expression Patterns That Predict Sensitivity To Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors In Lung Cancer Cell Lines And Human Lung Tumors, Justin M. Balko, Anil Potti, Christopher Saunders, Arnold J. Stromberg, Eric B. Haura, Esther P. Black Nov 2006

Gene Expression Patterns That Predict Sensitivity To Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors In Lung Cancer Cell Lines And Human Lung Tumors, Justin M. Balko, Anil Potti, Christopher Saunders, Arnold J. Stromberg, Eric B. Haura, Esther P. Black

Statistics Faculty Publications

BACKGROUND: Increased focus surrounds identifying patients with advanced non-small cell lung cancer (NSCLC) who will benefit from treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI). EGFR mutation, gene copy number, coexpression of ErbB proteins and ligands, and epithelial to mesenchymal transition markers all correlate with EGFR TKI sensitivity, and while prediction of sensitivity using any one of the markers does identify responders, individual markers do not encompass all potential responders due to high levels of inter-patient and inter-tumor variability. We hypothesized that a multivariate predictor of EGFR TKI sensitivity based on gene expression data would offer a …

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A Reverberation-Based Mass For The Central Black Hole In Ngc 4151, Misty C. Bentz, Kelly D. Denney, Edward M. Cackett, Matthias Dietrich, Jeffery K. Fogel, Himel Ghosh, Keith Horne, Charles Kuehn, Takeo Minezaki, Christopher A. Onken, Bradley M. Peterson, Richard W. Pogge, Vladimir I. Pronik, Douglas O. Richstone, Sergey G. Sergeev, Marianne Vestergaard, Matthew G. Walker, Yuzuru Yoshii Nov 2006

A Reverberation-Based Mass For The Central Black Hole In Ngc 4151, Misty C. Bentz, Kelly D. Denney, Edward M. Cackett, Matthias Dietrich, Jeffery K. Fogel, Himel Ghosh, Keith Horne, Charles Kuehn, Takeo Minezaki, Christopher A. Onken, Bradley M. Peterson, Richard W. Pogge, Vladimir I. Pronik, Douglas O. Richstone, Sergey G. Sergeev, Marianne Vestergaard, Matthew G. Walker, Yuzuru Yoshii

Physics and Astronomy Faculty Research Publications

We have undertaken a new ground-based monitoring campaign to improve the estimates of the mass of the central black hole in NGC 4151. We measure the lag time of the broad Hβ line response compared to the optical continuum at 5100 Å and find a lag of 6.6+1.1-0.8 days. We combine our data with the recent reanalysis of UV emission lines by Metzroth and coworkers to calculate a weighted mean of the black hole mass, MBH=(4.57+0.57-0.47)×107 Msolar. The absolute calibration of the black hole mass is based on normalization of …

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High-Resolution Imaging Of Proteins In Human Teeth By Scanning Probe Microscopy, Alexei Gruverman, D. Wu, B. J. Rodriguez, Sergei V. Kalinin, S. Habelitz Nov 2006

High-Resolution Imaging Of Proteins In Human Teeth By Scanning Probe Microscopy, Alexei Gruverman, D. Wu, B. J. Rodriguez, Sergei V. Kalinin, S. Habelitz

Alexei Gruverman Publications

High-resolution studies of dental tissues are of considerable interest for biomedical engineering and clinical applications. In this paper, we demonstrate the application of piezoresponse force microscopy (PFM) to nanoscale imaging of internal structure of human teeth by monitoring the local mechanical response to an electrical bias applied via a conductive tip. It is shown that PFM is capable of detecting dissimilar components of dental tissues, namely, proteins and calcified matrix, which have resembling morphology but different piezoelectric properties. It is demonstrated that collagen fibrils revealed in chemically treated intertubular dentin exhibit high piezoelectric activity and can be visualized in PFM …

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Robust Control Techniques Enabling Duty Cycle Experiments Utilizing A 6-Dof Crewstation Motion Base, A Full Scale Combat Hybrid Electric Power System, And Long Distance Internet Communications, Marc Compere, Jarrett Goodell, Miguel Simon, Wilford Smith, Mark Brudnak Nov 2006

Robust Control Techniques Enabling Duty Cycle Experiments Utilizing A 6-Dof Crewstation Motion Base, A Full Scale Combat Hybrid Electric Power System, And Long Distance Internet Communications, Marc Compere, Jarrett Goodell, Miguel Simon, Wilford Smith, Mark Brudnak

Publications

The RemoteLink effort supports the U.S. Army's objective for developing and fielding next generation hybrid-electric combat vehicles. It is a distributed soldierin- the-Ioop and hardware-in-the-Ioop environment with a 6-DOF motion base for operator realism, a full-scale combat hybrid electric power system, and an operational context provided by OneSAF. The driver/gunner crewstations rest on one of two 6-DOF motion bases at the U.S. Army TARDEC Simulation Laboratory (TSL). The hybrid power system is located 2,450 miles away at the TARDEC Power and Energy System Integration Laboratory (P&E SIL). The primary technical challenge in the RemoteLink is to operate both laboratories together …

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On Area-Stationary Surfaces In Certain Neutral Kaehler 4-Manifolds, Brendan Guilfoyle, Wilhelm Klingenberg Nov 2006

On Area-Stationary Surfaces In Certain Neutral Kaehler 4-Manifolds, Brendan Guilfoyle, Wilhelm Klingenberg

Publications

We study surfaces in TN that are area-stationary with respect to a neutral Kaehler metric constructed on TN from a riemannian metric g on N. We show that holomorphic curves in TN are area-stationary, while lagrangian surfaces that are area-stationary are also holomorphic and hence totally null. However, in general, area stationary surfaces are not holomorphic. We prove this by constructing counter-examples. In the case where g is rotationally symmetric, we find all area stationary surfaces that arise as graphs of sections of the bundle TN→N and that are rotationally symmetric. When (N,g) is the round 2-sphere, TN can be …

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Tetrakis(N-Ethyl-9-Oxo-4-Azonia-5-Aza-9h-Fluorene) Tetra-Μ3-Iodo-Hexa-Μ2-Iodo-Dodecaiodohexabismuthate, Meredith A. Tershany, Andrea M. Goforth, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye Nov 2006

Tetrakis(N-Ethyl-9-Oxo-4-Azonia-5-Aza-9h-Fluorene) Tetra-Μ3-Iodo-Hexa-Μ2-Iodo-Dodecaiodohexabismuthate, Meredith A. Tershany, Andrea M. Goforth, Mark D. Smith, Leroy Peterson Jr., Hans-Conrad Zur Loye

Faculty Publications

The new iodobismuthate compound (C13H11N2O)4[Bi6I22] has been synthesized solvothermally by reacting BiI3, Zn(NO3)2·6H2O and 4,5-diazafluoren-9-one in a water/ethanol solvent mixture. The asymmetric unit of the compound contains two independent [N-ethyl-4,5-dafo]+ cations and one-half of a centrosymmetric [Bi6I22]4- anion. The average terminal Bi-I, Bi-2-I and Bi-3-I bond lengths in the anion are 2.8923 (2), 3.1403 (2) and 3.3022 (2) Å, respectively.

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Early-Time Chromatic Variations In The Wind-Swept Medium Of Grb 021211 And The Faintness Of Its Afterglow, M. C. Nysewander, D. E. Reichart, H.-S. Park, G. G. Williams, K. Kinugasa, D. Q. Lamb, A. A. Henden, S. Klose, T. Kato, A Harper, H Yamaoka, C Laws, K Torii, D G. York, J C. Barentine, J Dembicky, R J. Mcmillan, J A. Moran, Dieter H. Hartmann, B Ketzeback, M B. Bayliss, J A. Crain, A C. Foster, M Schwartz, P Holvorcem, P A. Price, R Canterna, G B. Crew, G R. Ricker, S D. Barthelmy Nov 2006

Early-Time Chromatic Variations In The Wind-Swept Medium Of Grb 021211 And The Faintness Of Its Afterglow, M. C. Nysewander, D. E. Reichart, H.-S. Park, G. G. Williams, K. Kinugasa, D. Q. Lamb, A. A. Henden, S. Klose, T. Kato, A Harper, H Yamaoka, C Laws, K Torii, D G. York, J C. Barentine, J Dembicky, R J. Mcmillan, J A. Moran, Dieter H. Hartmann, B Ketzeback, M B. Bayliss, J A. Crain, A C. Foster, M Schwartz, P Holvorcem, P A. Price, R Canterna, G B. Crew, G R. Ricker, S D. Barthelmy

Publications

We present Follow-Up Network for Gamma-Ray Bursts (FUN GRB) Collaboration observations of the optical afterglow of GRB 021211 made between 143 s and 102 days after the burst. Our unique data set includes the earliest filtered detections and color information for an afterglow in the pre-Swift era. We find that the afterglow is best described by (1) a propagation through a wind-swept medium, (2) a cooling break that is blueward of the observed optical frequencies, and (3) a hard electron energy distribution. However, superimposed on this ‘‘standard model’’ behavior we find, one and possibly two, significant chromatic variations during the …

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Evidence For Two Kinematically Distinct Broad Emission Line Producing Regions In Active Galactic Nuclei, Stephanie A. Snedden, C. Martin Gaskell Nov 2006

Evidence For Two Kinematically Distinct Broad Emission Line Producing Regions In Active Galactic Nuclei, Stephanie A. Snedden, C. Martin Gaskell

C. Martin Gaskell Publications

We present the results of an analysis of line profiles of high- and low-ionization broad emission lines in 8 AGNs observed by the Hubble Space Telescope. We derive the physical conditions in the gas as a function of velocity. We find no evidence for a separate intermediate line region. For the broad line region as a whole we find a major contradiction between the velocity dependencies of conditions deduced from the major high-ionization lines and those deduced from the hydrogen lines alone if they are assumed to come from the same gas clouds. The hydrogen lines imply that the density …

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X-Ray/Ultraviolet Observing Campaign Of The Markarian 279 Active Galactic Nucleus Outflow: A Close Look At The Absorbing/Emitting Gas With Chandra-Letgs, E. Constantini, Jelle S. Kaastra, Nahum Arav, Gerard A. Kriss, K.C. Steenbrugge, Jack R. Gabel, F. Verbunt, Ehud Behar, C. Martin Gaskell, Kirk T. Korista, Daniel Proga, Jessica Kim-Quijano, J.E. Scott, Elizabeth S. Klimek, C.H. Hedrick Nov 2006

X-Ray/Ultraviolet Observing Campaign Of The Markarian 279 Active Galactic Nucleus Outflow: A Close Look At The Absorbing/Emitting Gas With Chandra-Letgs, E. Constantini, Jelle S. Kaastra, Nahum Arav, Gerard A. Kriss, K.C. Steenbrugge, Jack R. Gabel, F. Verbunt, Ehud Behar, C. Martin Gaskell, Kirk T. Korista, Daniel Proga, Jessica Kim-Quijano, J.E. Scott, Elizabeth S. Klimek, C.H. Hedrick

C. Martin Gaskell Publications

We present a Chandra-LETGS observation of the Seyfert 1 galaxy Mrk 279. This observation was carried out simultaneously with HST-STIS and FUSE, in the context of a multiwavelength study of this source. The Chandra pointings were spread over ten days for a total exposure time of ~360 ks. The maximal continuum flux variation is of the order of 30%. The spectrum of Mrk 279 shows evidence of broad emission features, especially at the wavelength of the O VII triplet. We quantitatively explore the possibility that this emission is produced in the broad line region (BLR). We modeled the broad …

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Nondipole Effects In Double Photoionization Of He, A.Y. Istomin, N. L. Manakov, A. V. Meremianin, Anthony F. Starace Nov 2006

Nondipole Effects In Double Photoionization Of He, A.Y. Istomin, N. L. Manakov, A. V. Meremianin, Anthony F. Starace

Anthony F. Starace Publications

Lowest-order nondipole effects are studied in double photoionization (DPI) of the He atom. Ah initio parametrizations of the quadrupole transition amplitude for DPI from the 1S0state are presented in terms of the exact two-electron reduced matrix elements. Parametrizations for the dipole-quadrupole triply differential cross section (TDCS) and doubly differential cross section (DDCS) are presented in terms of polarization-independent amplitudes for the case of an elliptically polarized photon. Expressions for the DDCS in terms of the reduced two-electron matrix elements are also given. A general analysis of retardation-induced asymmetries of the TDCS including the circular dichroism effect at …

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Subtidal Inner Shelf Currents Off Cartagena De Indias, Caribbean Coast Of Colombia, Mauro Maza, George Voulgaris, Bulusu Subrahmanyam Nov 2006

Subtidal Inner Shelf Currents Off Cartagena De Indias, Caribbean Coast Of Colombia, Mauro Maza, George Voulgaris, Bulusu Subrahmanyam

Faculty Publications

Seasonal trends in inner shelf subtidal circulation off the coast of Cartagena de Indias, Colombia, are examined through the analysis of current profiles, hydrographic, meteorological and satellite data collected from 1999 to 2002. During the dry season (December–April) the water column is well-mixed and along-shelf currents flow southwestward following the steady trade winds. In the rainy season (May –November) the water column experiences continuous events of stratification and the along-shelf currents flow northeastward, opposing the weak southwestward winds. In the dry season the along shelfcirculation is mostly driven by wind forcing, while in the rainy season, the circulation is set …

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Measurement Of The Cp-Violation Parameter Of B0 Mixing And Decay With Pp̅ → ΜμX Data, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration Nov 2006

Measurement Of The Cp-Violation Parameter Of B0 Mixing And Decay With Pp̅ → ΜμX Data, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Kenneth Bloom Publications

We measure the dimuon charge asymmetry A in pp̅ collisions at a center of mass energy √s =1960 GeV. The data was recorded with the D0 detector and corresponds to an integrated luminosity of approximately 1:0 fb-1. Assuming that the asymmetry A is due to asymmetric B0 ↔ B̅ mixing and decay, we extract the CP-violation parameter of B0 mixing and decay: [ℜ(∊B0)]/[1+∣∊B0∣2 = (AB0)/4 = -0.0023 ± 0.0011 (stat) ± 0.0008(syst). AB0 is the dimuon charge asymmetry from decays of B …

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Smoothed Rank Regression With Censored Data, Glenn Heller Nov 2006

Smoothed Rank Regression With Censored Data, Glenn Heller

Memorial Sloan-Kettering Cancer Center, Dept. of Epidemiology & Biostatistics Working Paper Series

A weighted rank estimating function is proposed to estimate the regression parameter vector in an accelerated failure time model with right censored data. In general, rank estimating functions are discontinuous in the regression parameter, creating difficulties in determining the asymptotic distribution of the estimator. A local distribution function is used to create a rank based estimating function that is continuous and monotone in the regression parameter vector. A weight is included in the estimating function to produce a bounded influence estimate. The asymptotic distribution of the regression estimator is developed and simulations are performed to examine its finite sample properties. …

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Properties Of Monotonic Effects, Tyler J. Vanderweele, James M. Robins Nov 2006

Properties Of Monotonic Effects, Tyler J. Vanderweele, James M. Robins

COBRA Preprint Series

Various relationships are shown hold between monotonic effects and weak monotonic effects and the monotonicity of certain conditional expectations. This relationship is considered for both binary and non-binary variables. Counterexamples are provide to show that the results do not hold under less restrictive conditions. The ideas of monotonic effects are furthermore used to relate signed edges on a directed acyclic graph to qualitative effect modification.

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Learning In Short-Time Horizons With Measurable Costs, Patrick Bowen Mullen Nov 2006

Learning In Short-Time Horizons With Measurable Costs, Patrick Bowen Mullen

Theses and Dissertations

Dynamic pricing is a difficult problem for machine learning. The environment is noisy, dynamic and has a measurable cost associated with exploration that necessitates that learning be done in short-time horizons. These short-time horizons force the learning algorithms to make pricing decisions based on scarce data. In this work, various machine learning algorithms are compared in the context of dynamic pricing. These algorithms include the Kalman filter, artificial neural networks, particle swarm optimization and genetic algorithms. The majority of these algorithms have been modified to handle the pricing problem. The results show that these adaptations allow the learning algorithms to …

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Threshold Effects In Strong-Field Detachment Of H- And F-: Plateau Enhancements And Angular Distribution Variations, Katarzyna Krajewska, Ilya I. Fabrikant, Anthony F. Starace Nov 2006

Threshold Effects In Strong-Field Detachment Of H- And F-: Plateau Enhancements And Angular Distribution Variations, Katarzyna Krajewska, Ilya I. Fabrikant, Anthony F. Starace

Anthony F. Starace Publications

Above-threshold detachment (ATD) rates for H1 and F1 ions in the high-energy plateau region are calculated as functions of photon number and laser intensity by solving the time-dependent Schrödinger equation within the Sturmian-Floquet approach. Pronounced enhancements of the ATD rates are found (up to an order of magnitude) as the laser-field intensity passes across ponderomotive-potential-induced channel closings. We confirm the zero-range potential model results of Borca et al. [Phys. Rev. Lett. 88, 193001 (2002)] for negative ions whose initial states have s symmetry, and we investigate here the case of initial states having p symmetry. Depending on …

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Multiple Testing With An Empirical Alternative Hypothesis, James E. Signorovitch Nov 2006

Multiple Testing With An Empirical Alternative Hypothesis, James E. Signorovitch

Harvard University Biostatistics Working Paper Series

An optimal multiple testing procedure is identified for linear hypotheses under the general linear model, maximizing the expected number of false null hypotheses rejected at any significance level. The optimal procedure depends on the unknown data-generating distribution, but can be consistently estimated. Drawing information together across many hypotheses, the estimated optimal procedure provides an empirical alternative hypothesis by adapting to underlying patterns of departure from the null. Proposed multiple testing procedures based on the empirical alternative are evaluated through simulations and an application to gene expression microarray data. Compared to a standard multiple testing procedure, it is not unusual for …

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Dynamic Shadow Removal From Front Projection Displays, Christopher O. Jaynes Nov 2006

Dynamic Shadow Removal From Front Projection Displays, Christopher O. Jaynes

Computer Science Faculty Patents

A technique and system for detecting a radiometric variation/artifacts of a front-projected dynamic display region under observation by at least one camera. The display is comprised of one or more images projected from one or more of a plurality of projectors; the system is preferably calibrated by using a projective relationship. A predicted image of the display region by the camera is constructed using frame-buffer information from each projector contributing to the display, which has been geometrically transformed for the camera and its relative image intensity adjusted. A detectable difference between a predicted image and the display region under observation …

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Random Dynamics (Siuc 2006 Outstanding Scholar Public Lecture), Salah-Eldin A. Mohammed Nov 2006

Random Dynamics (Siuc 2006 Outstanding Scholar Public Lecture), Salah-Eldin A. Mohammed

Miscellaneous (presentations, translations, interviews, etc)

No abstract provided.

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Phylogenetic Analysis Of Within-Host Serially-Sampled Viral Data, Patricia Buendia Nov 2006

Phylogenetic Analysis Of Within-Host Serially-Sampled Viral Data, Patricia Buendia

FIU Electronic Theses and Dissertations

The primary goal of this dissertation is the study of patterns of viral evolution inferred from serially-sampled sequence data, i.e., sequence data obtained from strains isolated at consecutive time points from a single patient or host. RNA viral populations have an extremely high genetic variability, largely due to their astronomical population sizes within host systems, high replication rate, and short generation time. It is this aspect of their evolution that demands special attention and a different approach when studying the evolutionary relationships of serially-sampled sequence data. New methods that analyze serially-sampled data were developed shortly after a groundbreaking HIV-1 study …

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