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2009

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Articles 61 - 90 of 6337

Full-Text Articles in Physical Sciences and Mathematics

A Super-Earth And Two Neptunes Orbiting The Nearby Sun-Like Star 61 Virginis, Steve Vogt, Robert A. Wittenmyer, R. Paul Butler, Simon O'Toole, Gregory W. Henry, Eugenio J. Rivera, Stefano Meschiari, Gregory Laughlin, Chris G. Tinney, Hugh R. A. Jones, Jeremy Bailey, Brad D. Carter, Konstantin Batygin Dec 2009

A Super-Earth And Two Neptunes Orbiting The Nearby Sun-Like Star 61 Virginis, Steve Vogt, Robert A. Wittenmyer, R. Paul Butler, Simon O'Toole, Gregory W. Henry, Eugenio J. Rivera, Stefano Meschiari, Gregory Laughlin, Chris G. Tinney, Hugh R. A. Jones, Jeremy Bailey, Brad D. Carter, Konstantin Batygin

Information Systems and Engineering Management Research Publications

We present precision radial velocity data that reveal a multiple exoplanet system orbiting the bright nearby G5V star 61 Virginis. Our 4.6 years of combined Keck/HIRES and Anglo-Australian Telescope precision radial velocities indicate the hitherto unknown presence of at least three planets orbiting this well-studied star. These planets are all on low-eccentricity orbits with periods of 4.2, 38.0, and 124.0 days, and projected masses (Msin i) of 5.1, 18.2, and 24.0 M⊕, respectively. Test integrations of systems consistent with the radial velocity data suggest that the configuration is dynamically stable. Depending on the effectiveness of tidal dissipation within the inner …


Selective Complexation And Reactivity Of Metallic Nitride And Oxometallic Fullerenes With Lewis Acids And Use As An Effective Purification Method, Steven Stevenson, Mary A. Mackey, Jane E. Pickens, Melissa A. Stuart, Bridget S. Confait, J. Paige Phillips Dec 2009

Selective Complexation And Reactivity Of Metallic Nitride And Oxometallic Fullerenes With Lewis Acids And Use As An Effective Purification Method, Steven Stevenson, Mary A. Mackey, Jane E. Pickens, Melissa A. Stuart, Bridget S. Confait, J. Paige Phillips

Faculty Publications

Metallic nitride fullerenes (MNFs) and oxometallic fullerenes (OMFs) react quickly with an array of Lewis acids. Empty-cage fullerenes are largely unreactive under conditions used in this study. The reactivity order is Sc4O2@Ih-C80 > Sc3N@C78 > Sc3N@C68 > Sc3N@D5h-C80 > Sc3N@Ih-C80. Manipulations of Lewis acids, molar ratios, and kinetic differences within the family of OMF and MNF metallofullerenes are demonstrated in a selective precipitation scheme, which can be used either alone for purifying Sc3N@Ih …


Modeling Residential Foreclosures In Kent County, Kaitlyn Ratkowiak Dec 2009

Modeling Residential Foreclosures In Kent County, Kaitlyn Ratkowiak

Student Summer Scholars Manuscripts

Residential Foreclosures in Kent County have become commonplace in the past few years. In this project, we hope to analyze data on foreclosures since 2004 to learn more about the mounting crisis, with the hope that we can identify neighborhoods at risk of foreclosures and its associated consequences.


Solid State And Solution Dynamics Of Pyridine Based Tetraaza- Macrocyclic Lanthanide Chelates Possessing Phosphonate Ligating Functionality (Ln-Pctmb): Effect On Relaxometry And Optical Properties, Garry Kiefer, Mark Woods Dec 2009

Solid State And Solution Dynamics Of Pyridine Based Tetraaza- Macrocyclic Lanthanide Chelates Possessing Phosphonate Ligating Functionality (Ln-Pctmb): Effect On Relaxometry And Optical Properties, Garry Kiefer, Mark Woods

Chemistry Faculty Publications and Presentations

The macrocyclic ligand 3,6,9-tris(methylenebutyl phosphonic acid)-3,6,9−15-tetraazabicyclo [9.3.1]pentadeca-1(15),11,13-triene (PCTMB) was synthesized and complexes of Eu3+, Tb3+, and Gd3+ studied by X-ray crystallography, luminescence, and relaxometry. In the crystal these complexes are dimeric and possess 8-coordinate Ln3+ centers that are linked by bridging phosphonates. The rigidity introduced by the pyridyl nucleus forces the EuPCTMB and TbPCTMB to adopt a twisted snub disphenoid (TSD) coordination geometry. Examination of the 5D07F0 luminescent transition of EuPCTMB in the solid state confirmed the existence of a single distinct Eu3+ coordination environment, whereas two …


Vitis Seeds (Vitaceae) From The Late Neogene Gray Fossil Site, Northeastern Tennessee, Usa., Fade Gong Dec 2009

Vitis Seeds (Vitaceae) From The Late Neogene Gray Fossil Site, Northeastern Tennessee, Usa., Fade Gong

Electronic Theses and Dissertations

This study focuses on the morphometric and systematic studies of fossil vitaceous seeds recently recovered from the Gray Fossil Site (7-4.5 Ma, latest Miocene-earliest Pliocene) northeastern Tennessee. Morphologically, all fossil seeds correspond to the extant subgenus Vitis (genus Vitis) of the Vitaceae based on the smooth dorsal surface with a centrally positioned chalaza connected with a conspicuous chalaza-apex groove and short linear ventral infolds that are slightly diverged apically. A multivariate analysis based on 11 measured characters from 76 complete seeds identified three types of seeds, each representing a distinct morphotaxon. Based on comparison with modern and fossil vitaceous …


Predicting Flavonoid Ugt Regioselectivity With Graphical Residue Models And Machine Learning., Arthur Rhydon Jackson Dec 2009

Predicting Flavonoid Ugt Regioselectivity With Graphical Residue Models And Machine Learning., Arthur Rhydon Jackson

Electronic Theses and Dissertations

Machine learning is applied to a challenging and biologically significant protein classification problem: the prediction of flavonoid UGT acceptor regioselectivity from primary protein sequence. Novel indices characterizing graphical models of protein residues are introduced. The indices are compared with existing amino acid indices and found to cluster residues appropriately. A variety of models employing the indices are then investigated by examining their performance when analyzed using nearest neighbor, support vector machine, and Bayesian neural network classifiers. Improvements over nearest neighbor classifications relying on standard alignment similarity scores are reported.


A Variation Of The Carleman Embedding Method For Second Order Systems., Charles Nunya Dzacka Dec 2009

A Variation Of The Carleman Embedding Method For Second Order Systems., Charles Nunya Dzacka

Electronic Theses and Dissertations

The Carleman Embedding is a method that allows us to embed a finite dimensional system of nonlinear differential equations into a system of infinite dimensional linear differential equations. This technique works well when dealing with first-order nonlinear differential equations. However, for higher order nonlinear ordinary differential equations, it is difficult to use the Carleman Embedding method. This project will examine the Carleman Embedding and a variation of the method which is very convenient in applying to second order systems of nonlinear equations.


Determination Of The Activation Parameters Of Reaction Between [Fe(Cn6]-4 And K[Co(Hedta)No2]., Sammy Eni Eni Dec 2009

Determination Of The Activation Parameters Of Reaction Between [Fe(Cn6]-4 And K[Co(Hedta)No2]., Sammy Eni Eni

Electronic Theses and Dissertations

The kinetics of the oxidation of [Fe(CN)6]-4 by K[Co(HEDTA)NO2] was studied in order to get the mechanism and the activation parameters of the reaction. Using a freshly-made Na3PO4 solution as the reaction medium with a pH of 6.00 the ionic strength was maintained at 0.10 M and the buffer molarity was 0.001 M.

The rate constant (kobs) of the reaction between [Fe(CN)6]-4 and K[Co(HEDTA)NO2] was determined at temperatures of 25.0°C, 27.5°C, 30.0°C, 35.0°, and 40.0°C. We explored this reaction by monitoring the evolution of ferricyanide, …


Ua12/13 Resolution For Education For Sustainability At Wku, Office Of Sustainability, Christian Ryan-Downing Dec 2009

Ua12/13 Resolution For Education For Sustainability At Wku, Office Of Sustainability, Christian Ryan-Downing

Sustainability Publications and Resources

No abstract provided.


Discovery Of Very High Energy Gamma Rays From Pks 1424+240 And Multiwavelength Constraints On Its Redshift, P. T. Reynolds, Et Al Dec 2009

Discovery Of Very High Energy Gamma Rays From Pks 1424+240 And Multiwavelength Constraints On Its Redshift, P. T. Reynolds, Et Al

Physical Sciences Publications

We report the first detection of very high energy83Gamma-ray emission above 100 GeV. (VHE) gamma-ray emission above 140 GeV from PKS 1424+240, a BL Lac object with an unknown redshift. The photon spectrum above 140 GeV measured by VERITAS is well described by a power law with a photon index of 3.8 ± 0.5stat ± 0.3syst and a flux normalization at 200 GeV of (5.1 ± 0.9stat ± 0.5syst) × 10–11 TeV–1 cm–2 s–1, where stat and syst denote the statistical and systematical uncertainties, respectively. The VHE flux is steady over the observation period between MJD 54881 and 55003 (from …


Voting, The Symmetric Group, And Representation Theory, Zajj Daugherty '05, Alexander K. Eustis '06, Gregory Minton '08, Michael E. Orrison Dec 2009

Voting, The Symmetric Group, And Representation Theory, Zajj Daugherty '05, Alexander K. Eustis '06, Gregory Minton '08, Michael E. Orrison

All HMC Faculty Publications and Research

We show how voting may be viewed naturally from an algebraic perspective by viewing voting profiles as elements of certain well-studied QSn-modules. By using only a handful of simple combinatorial objects (e.g., tabloids) and some basic ideas from representation theory (e.g., Schur's Lemma), this allows us to recast and extend some well-known results in the field of voting theory.


Modulation Of Restriction Enzyme Pvuii Activity By Metal Ion Cofactors, Charulata Bhaskaran Prasannan Dec 2009

Modulation Of Restriction Enzyme Pvuii Activity By Metal Ion Cofactors, Charulata Bhaskaran Prasannan

Dissertations

Metal ions like Ca2+, Mn2+, Tb3+, Eu3+ etc., can bind at the active site and have varying effects on the enzymatic activity. In a crystal structure with DNA, two Ca2+ ions were bound to the active site of each PvuII monomer, and the metals share the ligands. Ca2+ ions promote DNA binding and not cleavage in many nucleases. We explored the role of Mg2+ and Ca2+ binding at the metal binding sites of PvuII to elucidate the role of each metal site. We monitored the cleavage kinetics of PvuII in presence of mixed metals. The cleavage kinetics data for Ca2+ …


Replacing Hydrogen Bonds With Coordinate Covalent Bonds In Coordination Networks, Colin Stewart Rodger Dec 2009

Replacing Hydrogen Bonds With Coordinate Covalent Bonds In Coordination Networks, Colin Stewart Rodger

Dissertations

The overall theme of the dissertation is that metal ions such as silver(I) can replace H+ in hydrogen bonded organic frameworks. Because organic solids have been extensively studied, we can insert metal ions into the supramolecular assemblies, thus creating predictable coordination solids of varying dimensions. One example of an organic solid tested involves the organic compounds terephthalic and isophthalic acids. These dicarboxylic acids have previously been shown to self-assemble into tape-like structures via hydrogen bonding, with neighboring dicarboxylic acids located at angles of 180° and 120° respectively. By substituting the hydrogen bonds with coordination metal-ligand bonds similar assemblies are formed. …


Hybrid Matching And Risk Assessment Of The Misspelled Names Hmra, Cihan Varol Dec 2009

Hybrid Matching And Risk Assessment Of The Misspelled Names Hmra, Cihan Varol

Theses and Dissertations

Companies acquire personal information from phone, World Wide Web, or email in order to sell or send an advertisement about their product. However, when this information is acquired, moved, copied or edited, the data may loose its quality. Often, the use of data administrators or a tool that has limited capabilities to correct the mistyped information can cause many problems. Moreover, most of the correction techniques are particularly implemented for the words used in daily conversations. Since personal names have different characteristics compared to general text, firstly, we proposed a hybrid matching algorithm (PNRS) which employs phonetic encoding, string matching …


Real Time Network Monitoring And Reporting System, Ricky Lee Massengale Sr. Dec 2009

Real Time Network Monitoring And Reporting System, Ricky Lee Massengale Sr.

Theses and Dissertations

With the ability of modern system developers to develop intelligent programs that allows machines to learn, modify and evolve themselves, current trends of reactionary methods to detect and eradicate malicious software code from infected machines is proving to be too costly. Addressing malicious software after an attack is the current methodology and should be a fallback approach. A modern approach should be to perpetually monitor the "enterprise network backbone" traffic and broadcast alerts while taking protective and pre-emptive measures, in the event that the traffic falls out of the bounds of pre-described norms. This work demonstrates that a synergy approach …


Carbon Coated Tellurium For Optical Data Storage, Jonathan D. Abbott Dec 2009

Carbon Coated Tellurium For Optical Data Storage, Jonathan D. Abbott

Theses and Dissertations

A highly durable optical disk has been developed for data archiving. This optical disk uses tellurium as the write layer and carbon as a dielectric and oxidation prevention layer. The sandwich style CTeC film was deposited on polycarbonate and silicon substrates by plasma sputtering. These films were then characterized with SEM, TEM, EELS, ellipsometry, ToF-SIMS, etc, and were tested for writability and longevity. Results show the films were uniform in physical structure, are stable, and able to form permanent pits. Data was written to a disk and successfully read back in a commercial DVD drive.


Multiwavelength Studies Of Lsi+61°303, Michael E. Fahrenwald Dec 2009

Multiwavelength Studies Of Lsi+61°303, Michael E. Fahrenwald

Theses and Dissertations

LSI+61°303 is a member of a small class of X-ray binary stars that are also sources of strong radio emission. It has been detected as a periodic radio source with the NRAO Very Large Array, a magnitude 10.7 B0 star, a 0.5-5 keV X-ray source by the Einstein X-ray satellite and may be associated with an unidentified 100 MeV γ-ray source discovered by the Compton Gamma Ray Observatory satellite. Theories exist which suggest that binary systems are capable of emitting γ-rays at energies > 100 GeV. A similar system, PSR B1259-63, has been found to emit γ-rays at TeV energies. In …


Reevaluating The Cosmological Origin Of Dark Matter, Scott Watson Dec 2009

Reevaluating The Cosmological Origin Of Dark Matter, Scott Watson

Physics - All Scholarship

The origin of dark matter as a thermal relic offers a compelling way in which the early universe was initially populated by dark matter. Alternative explanations typically appear exotic compared to the simplicity of thermal production. However, recent observations and progress from theory suggest that it may be necessary to be more critical. This is important because ongoing searches probing the microscopic properties of dark matter typically rely on the assumption of dark matter as a single, unique, thermal relic. On general grounds I will argue that non-thermal production of dark matter seems to be a robust prediction of physics …


Aerosol Optical Depth Retrieval For Spot Hrv Images, Chien-Hui Liu, Gin-Rong Liu Dec 2009

Aerosol Optical Depth Retrieval For Spot Hrv Images, Chien-Hui Liu, Gin-Rong Liu

Journal of Marine Science and Technology–Taiwan

Atmospheric aerosol is an important factor of the Earth’s radiation budget. The aerosol optical depth (AOD) is also the key parameter in generating surface products from remotely sensed data. An image-based retrieval algorithm of aerosol characteristics and surface reflectance is used to retrieve the AOD from SPOT satellite images in this paper. The accuracy of retrieved AOD is assessed using sunphotometer measurements. SPOT satellite images in Jhongli , Taoyuan county are used to testify the algorithm. The results show that the rootmean-square error (RMSE) of the retrieved AOD at 0.55 µm is 0.10. Over the range of measured AOD 0.08~0.34, …


The Acs Survey Of Galactic Globular Clusters. Ix. Horizontal Branch Morphology And The Second Parameter Phenomenon, Aaron Dotter, Ata Sarajedini, Jay Anderson, Antonio Aparicio, Luigi R. Bedin, Brian Chaboyer Dec 2009

The Acs Survey Of Galactic Globular Clusters. Ix. Horizontal Branch Morphology And The Second Parameter Phenomenon, Aaron Dotter, Ata Sarajedini, Jay Anderson, Antonio Aparicio, Luigi R. Bedin, Brian Chaboyer

Dartmouth Scholarship

The horizontal branch (HB) morphology of globular clusters (GCs) is most strongly influenced by metallicity. The second parameter phenomenon, first described in the 1960s, acknowledges that metallicity alone is not enough to describe the HB morphology of all GCs. In particular, astronomers noticed that the outer Galactic halo contains GCs with redder HBs at a given metallicity than are found inside the solar circle. Thus, at least a second parameter was required to characterize HB morphology. While the term "second parameter" has since come to be used in a broader context, its identity with respect to the original problem has …


Mean Survival Time From Right Censored Data, Ming Zhong, Kenneth R. Hess Dec 2009

Mean Survival Time From Right Censored Data, Ming Zhong, Kenneth R. Hess

COBRA Preprint Series

A nonparametric estimate of the mean survival time can be obtained as the area under the Kaplan-Meier estimate of the survival curve. A common modification is to change the largest observation to a death time if it is censored. We conducted a simulation study to assess the behavior of this estimator of the mean survival time in the presence of right censoring.

We simulated data from seven distributions: exponential, normal, uniform, lognormal, gamma, log-logistic, and Weibull. This allowed us to compare the results of the estimates to the known true values and to quantify the bias and the variance. Our …


Analysis Of Transient Growth In Iterative Learning Control Using Pseudospectra, Douglas A. Bristow, John R. Singler Dec 2009

Analysis Of Transient Growth In Iterative Learning Control Using Pseudospectra, Douglas A. Bristow, John R. Singler

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper we examine the problem of transient growth in Iterative Learning Co ntrol (ILC). Transient growth is generally avoided in design by using robust monotonic convergence (RMC) criteria. However, RMC leads to fundamental performance limitations. We consider the possibility of allowing safe transient growth in ILC algorithms as a means to circumvent these limitations. Here the pseudospectra is used for the first time to study transient growth in ILC. Basic properties of the pseudospectra that are relevant to the ILC problem are presented. Two ILC design problems are considered and examined using pseduospectra. The pseudospectra provides new results …


Performance Of Dmt-Based Liquefaction Evaluation Methods On Case Histories Of Chi-Chi Earthquake, Gordon Tung-Chin Kung, Der-Her Lee, Pai-Hsiang Tsai Dec 2009

Performance Of Dmt-Based Liquefaction Evaluation Methods On Case Histories Of Chi-Chi Earthquake, Gordon Tung-Chin Kung, Der-Her Lee, Pai-Hsiang Tsai

Journal of Marine Science and Technology–Taiwan

This study examines two recently-developed DMT-based methods, one CRR7.5-KD boundary curve and one CRR7.5-ED boundary curve, for evaluating the liquefaction resistance of soils using in-situ test data. The collected data consist of a number of liquefied and non-liquefied case histories, which were performed shortly after the disastrous Chi-Chi earthquake in 1999. The results of examining the CRR7.5-KD and CRR7.5-ED boundary curves showed that both curves are capable of accurately estimating the liquefaction resistance of soils and thus the liquefaction potential of soils. The developed DMT-based methods therefore have the potential to be an alternative to the existing procedure of liquefaction …


Unsteady Motions Of Separated Shear Layer In Wake Flow Due To Upstream Disturbance, Chin-Tsan Wang, Jun-Ji Miau, Cheng Kuang Shaw Dec 2009

Unsteady Motions Of Separated Shear Layer In Wake Flow Due To Upstream Disturbance, Chin-Tsan Wang, Jun-Ji Miau, Cheng Kuang Shaw

Journal of Marine Science and Technology–Taiwan

The phenomenon of physical wake flow is complex and remains relatively unknown, especially for the relationship between the span-wise motions of separated shear layers and low frequency variations embedded in the vortex shedding process of upstream disturbances. In this study experiments were executed by situating a mesh grid and controlling cylinder upstream. Results showed that the integral time scale of the span-wise motions for a separated shear layer was close to that of the low frequency variations for an upstream disturbance. This evidence supports the idea that span-wise motions of a separated shear layer and the low frequency variations should …


Measured Optical Constants Of Copper From 10 Nm To 35 Nm, David D. Allred, Nicole Brimhall, Nicholas Herrick, Justin Peatross, R. Steven Turley, Michael Ware Dec 2009

Measured Optical Constants Of Copper From 10 Nm To 35 Nm, David D. Allred, Nicole Brimhall, Nicholas Herrick, Justin Peatross, R. Steven Turley, Michael Ware

Faculty Publications

We use laser high-order harmonics and a polarization-ratioreflectance technique to determine the optical constants of copper and oxidized copper in the wavelength range 10-35 nm. This measurement resolves previously conflicting data sets, where disagreement on optical constants of copper in the extreme ultraviolet most likely arises from inadvertent oxidation of samples before measurement.


The 2009-2010 El Nino: Hydrologic Relief To U.S. Regions, Glenn A. Tootle, Thomas C. Piechota, Oubeidillah Aziz, William Paul Miller, Venkat Lakshmi, John A. Dracup, Carly Jerla Dec 2009

The 2009-2010 El Nino: Hydrologic Relief To U.S. Regions, Glenn A. Tootle, Thomas C. Piechota, Oubeidillah Aziz, William Paul Miller, Venkat Lakshmi, John A. Dracup, Carly Jerla

Civil and Environmental Engineering and Construction Faculty Research

Current forecasts by the U.S. National Oceanic and Atmospheric Administration (NOAA) are that the Pacific Ocean will experience El Niño conditions in late 2009 and into 2010. These forecasts are similar to past El Niño events in 1972–1973, 1982–1983, 1986–1987, and 2002–2003.

Evaluating the hydrologic conditions for these past El Niño events reveals that during these times, surface water supply conditions improved in many parts of the United States, including the Southeast, Midwest, and Southwest. At the same time, the Pacific Northwest and other specific regions of the United States experienced below-average water supply conditions. This is consistent with the …


Mathematical Sciences News, Georgia Southern University Dec 2009

Mathematical Sciences News, Georgia Southern University

Mathematical Sciences News (2007-2021)

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Realizing The Technical Advantages Of Star Transformation, Karen L. Darling Dec 2009

Realizing The Technical Advantages Of Star Transformation, Karen L. Darling

Regis University Student Publications (comprehensive collection)

Data warehousing and business intelligence go hand in hand, each gives the other purpose for development, maintenance and improvement. Both have evolved over a few decades and build upon initial development. Management initiatives further drive the need and complexity of business intelligence, while in turn expanding the end user community so that business change, results and strategy are affected at the business unit level. The literature, including a recent business intelligence user survey, demonstrates that query performance is the most significant issue encountered. Oracle's data warehouse 10g.2 is examined with improvements to query optimization via "best practice" through Star Transformation. …


An Investigation Into Rewriting A Security Policy For Loreto College, Paul M. Mwai Dec 2009

An Investigation Into Rewriting A Security Policy For Loreto College, Paul M. Mwai

Regis University Student Publications (comprehensive collection)

Computers as well as the networking environments in which they operate have evolved into highly sophisticated and complex systems. The intricacy of these systems and especially the relationship between them forms the greatest area of vulnerabilities for organizations. (Whitman and Mattord, 2004) Information needs to be transmitted to and from the organization, and thus may be vulnerable within certain stages along the communications line. If at any stage of the process, the information is compromised, it could have a negative impact on the entire organization. Protective measures such as disaster recover plans, encryption/ decryption, and information system security controls, can …


The Effect Of Consumerism And Regulation On Household Solid Waste Management In The United States And Germany: A Comparative Study, Amir Vafa Dec 2009

The Effect Of Consumerism And Regulation On Household Solid Waste Management In The United States And Germany: A Comparative Study, Amir Vafa

School of Natural Resources: Dissertations, Theses, and Student Research

Private household recycling is a significant aspect of consumerism in economically developed countries and the inevitable question of household waste management has gained more importance among municipalities in recent years. The present study examined the effect of regulation on household solid waste management. Within a comparative, qualitative framework, the study explored and evaluated the pro-regulatory effects in Germany and the anti-regulatory policies in the United States by means of comparing two similar communities, Lincoln, Nebraska and Augsburg, Germany. By examining the present legislations, official documents, legal and operational procedures, and other relevant artifacts, laws, regulations and the degree of their …