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Articles 92671 - 92700 of 142946

Full-Text Articles in Physical Sciences and Mathematics

Global Conservation Of Biodiversity And Ecosystem Services, Will R. Turner, Katrina Brandon, Thomas M. Brooks, Robert Costanza Nov 2007

Global Conservation Of Biodiversity And Ecosystem Services, Will R. Turner, Katrina Brandon, Thomas M. Brooks, Robert Costanza

Institute for Sustainable Solutions Publications and Presentations

Habitat destruction has driven much of the current biodiversity extinction crisis, and it compromises the essential benefits, or ecosystem services, that humans derive from functioning ecosystems. Securing both species and ecosystem services might be accomplished with common solutions. Yet it is unknown whether these two major conservation objectives coincide broadly enough worldwide to enable global strategies for both goals to gain synergy. In this article, we assess the concordance between these two objectives, explore how the concordance varies across different regions, and examine the global potential for safeguarding biodiversity and ecosystem services simultaneously. We find that published global priority maps …

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Inference On Overlapping Coefficients In Two Exponential Populations, Mohammad F. Al-Saleh, Hani M. Samawi Nov 2007

Inference On Overlapping Coefficients In Two Exponential Populations, Mohammad F. Al-Saleh, Hani M. Samawi

Biostatistics Faculty Publications

Three measures of overlap, namely Matusita’s measureρ , Morisita’s measure λ and Weitzman’s measure Δ are investigated in this article for two exponential populations with different means. It is well that the estimators of those measures of overlap are biased. The bias is of these estimators depends on the unknown overlap parameters. There are no closed-form, exact formulas, for those estimators variances or their exact sampling distributions. Monte Carlo evaluations are used to study the bias and precision of the proposed overlap measures. Bootstrap method and Taylor series approximation are used to construct confidence intervals for the overlap measures.

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Optimization Of Electrostatic Interactions In Protein-Protein Complexes, Kelly Brock, Kemper Talley, Kacey Coley, Petras Kundrotas, Emil Alexov Nov 2007

Optimization Of Electrostatic Interactions In Protein-Protein Complexes, Kelly Brock, Kemper Talley, Kacey Coley, Petras Kundrotas, Emil Alexov

Publications

In this article, we present a statistical analysis of the electrostatic properties of 298 protein-protein complexes and 356 domain-domain structures extracted from the previously developed database of protein complexes (ProtCom, http://www.ces.clemson.edu/compbio/protcom). For each structure in the dataset we calculated the total electrostatic energy of the binding and its two components, Coulombic and reaction field energy. It was found that in a vast majority of the cases (>90%), the total electrostatic component of the binding energy was unfavorable. At the same time, the Coulombic component of the binding energy was found to favor the complex formation while …

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On Enumeration Of Conjugacy Classes Of Coxeter Elements, Matthew Macauley, Henning S. Mortveit Nov 2007

On Enumeration Of Conjugacy Classes Of Coxeter Elements, Matthew Macauley, Henning S. Mortveit

Publications

In this paper we study the equivalence relation on the set of acyclic orientations of a graph Y that arises through source-to-sink conversions. This source-to-sink conversion encodes, e.g. conjugation of Coxeter elements of a Coxeter group. We give a direct proof of a recursion for the number of equivalence classes of this relation for an arbitrary graph Y using edge deletion and edge contraction of non-bridge edges. We conclude by showing how this result may also be obtained through an evaluation of the Tutte polynomial as T (Y, 1, 0), and we provide bijections to two other classes of acyclic …

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Priority Of Concerns Worksheet (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc. Nov 2007

Priority Of Concerns Worksheet (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc.

Public Meetings

No abstract provided.

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Interactive Public Meetings Announcement - November 2007, Horsley Witten Group, Inc. Nov 2007

Interactive Public Meetings Announcement - November 2007, Horsley Witten Group, Inc.

Public Meetings

No abstract provided.

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List Of Issues Identified By Participants In The November 2007 Public Meetings, Horsley Witten Group, Inc. Nov 2007

List Of Issues Identified By Participants In The November 2007 Public Meetings, Horsley Witten Group, Inc.

Public Meetings

No abstract provided.

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Management Plan Figure (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc. Nov 2007

Management Plan Figure (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc.

Public Meetings

No abstract provided.

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Taunton River Water Budget (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc. Nov 2007

Taunton River Water Budget (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc.

Public Meetings

No abstract provided.

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Taunton River Watershed Study Public Meeting Presentation (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc. Nov 2007

Taunton River Watershed Study Public Meeting Presentation (November 2007 Interactive Public Meetings), Horsley Witten Group, Inc.

Public Meetings

No abstract provided.

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The Correlation Coefficients, Rudy Gideon Nov 2007

The Correlation Coefficients, Rudy Gideon

Mathematical Sciences Faculty Publications

A generalized method of defining and interpreting correlation coefficients is given. Seven correlation coefficients are defined — three for continuous data and four on the ranks of the data. A quick calculation of the rank based correlation coefficients using a 0-1 graph-matrix is shown. Examples and comparisons are given.

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Ais Binary Messages, Domain Examples And A Case For A Xml Message Definition Language, Schwehr Kurt Nov 2007

Ais Binary Messages, Domain Examples And A Case For A Xml Message Definition Language, Schwehr Kurt

Center for Coastal and Ocean Mapping

No abstract provided.

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Encoding Ais Binary Messages In Xml Format For Providing Hydrographic-Related Information, Schwehr Kurt, Lee Alexander Nov 2007

Encoding Ais Binary Messages In Xml Format For Providing Hydrographic-Related Information, Schwehr Kurt, Lee Alexander

Center for Coastal and Ocean Mapping

A specification is proposed to enable hydrographic and maritime safety agencies to encode AIS messages using Extensible Markup Language (XML). It specifies the order, length, and type of fields contained in ITU-R.M.1371-1. A XML schema validates the message definitions, and a XSLT style sheet produces reference documentation in 'html' format. AIS binary messages in XML are an effective means to communicate dynamic and real-time port/waterway information. For example, tidal information can be continuously broadcast to maritime users and applied to a "tide-aware" ENC. The XML format aligns with the type of data encapsulation planned for the IHO Geospatial Standard for …

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Can Superior Crm Capabilities Improve Performance In Banking, T. R. Coltman Nov 2007

Can Superior Crm Capabilities Improve Performance In Banking, T. R. Coltman

Faculty of Informatics - Papers (Archive)

The market enthusiasm generated around investment in customer relationship management (CRM) technology is in stark contrast to the nay-saying by many academic and business commentators. This raises an important research question concerning the extent to which banks should continue to invest in CRM technology. Drawing on field interviews and a survey of senior bank executives the results reveal that a superior CRM capability can deliver improved performance. The paper then demonstrates that in order to be most successful, CRM programs require a combination of technical, human and business capabilities.

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Race: A Robust Adaptive Caching Strategy For Buffer Cache, Yifeng Zhu, Hong Jiang Nov 2007

Race: A Robust Adaptive Caching Strategy For Buffer Cache, Yifeng Zhu, Hong Jiang

School of Computing: Faculty Publications

While many block replacement algorithms for buffer caches have been proposed to address the well-known drawbacks of the LRU algorithm, they are not robust and cannot maintain an consistent performance improvement over all workloads. This paper proposes a novel and simple replacement scheme, called RACE (Robust Adaptive buffer Cache management schemE), which differentiates the locality of I/O streams by actively detecting access patterns inherently exhibited in two correlated spaces: the discrete block space of program contexts from which I/O requests are issued and the continuous block space within files to which I/O requests are addressed. This scheme combines global I/O …

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Integrated Approach To The Toxicity Evaluation Of Irish Marine Sediments: Exotoxicological Assessment, Ailbhe Macken Nov 2007

Integrated Approach To The Toxicity Evaluation Of Irish Marine Sediments: Exotoxicological Assessment, Ailbhe Macken

Doctoral

The quality of sediment in any aquatic ecosystem is vital to the health of that system. Sediments have been recognised as a major repository for persistent toxic substances. If sediments become sufficiently polluted they can lead to the disruption of surrounding natural biological communities. Therefore the monitoring of sediment quality is essential for successful ecosystem functioning in the marine environment. The aim of the present study was to employ an integrated approach of the toxicity evaluation of Irish marine sediments by correlating results of biotests with chemical analysis. Between 2004 and 2006 the Radiation and Environmental Science Centre (RESC) participate …

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Biofuel Feedstocks: The Risk Of Future Invasions, Joseph M. Ditomaso, Jacob N. Barney, Allison M. Fox Nov 2007

Biofuel Feedstocks: The Risk Of Future Invasions, Joseph M. Ditomaso, Jacob N. Barney, Allison M. Fox

All U.S. Government Documents (Utah Regional Depository)

In an effort to decrease greenhouse gas emissions, expand domestic energy production, and maintain economic growth, public and private investments are being used to pursue dedicated feedstock crops for biofuel production. Unlike food crops grown for grain-based ethanol (e.g., corn), which require high inputs of fertilizers and pesticides and typically are grown on prime agricultural land, proposed lignocellulose-based energy crops (e.g., switchgrass) typically have a neutral or negative carbon budget, require relatively few economic or environmental inputs, and can be cultivated on marginal, lower-productivity land. Thus, a rapidly growing industry related to crop selection, cultivar improvement, and conversion technilogies is …

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Refuge Update – November/December 2007, Volume 4, Number 6 Nov 2007

Refuge Update – November/December 2007, Volume 4, Number 6

RefugeUpdate (USFWS-NWRS)

Table of Contents:

Celebrating 20 Years of Science on the M/ V Tiglax, page 5 Kevin Bell is honored as Captain of the largest ship operated by the National Wildlife Refuge System.

Focus on…A River Runs Through It, pages 8-15 Rivers on refuges are managed for recreation, habitat restoration, water rights and sheer beauty.

The Fight Against Giant Salvinia, page 18 Caddo Lake National Wildlife Refuge in Texas is fighting a weed that can travel three-quarters of a mile in 24 hours.

Awards, page 21 From protecting the land to going “green,” awards recognize excellence.

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Search For BS0→ Μ+ Μ- Decays At D0, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration Nov 2007

Search For BS0→ Μ+ Μ- Decays At D0, V. M. Abazov, Kenneth A. Bloom, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We report results from a search for the decay Bs0 → μ+μ- using 1.3 fb-1 of pp̅ collisions at √s= 1.96 TeV collected by the D0 experiment at the Fermilab Tevatron Collider.We find two candidate events, consistent with the expected background of 1.24 ± 0.99, and set an upper limit on the branching fraction of Ɓ(Bs0 → μ+μ-) < 1.2 x 10-7 at the 95% C.L.

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Ammonia Elimination From Protonated Nucleobases And Related Synthetic Substrates, Ming Qian, Shuo Yang, Hong Wu, Papiya S. Majumdar, Nathan D. Leigh, Rainer Glaser Nov 2007

Ammonia Elimination From Protonated Nucleobases And Related Synthetic Substrates, Ming Qian, Shuo Yang, Hong Wu, Papiya S. Majumdar, Nathan D. Leigh, Rainer Glaser

Chemistry Faculty Research & Creative Works

The results are reported of mass-spectrometric studies of the nucleobases adenine 1h (1, R = H), guanine 2h, and cytosine 3h. The protonated nucleobases are generated by electrospray ionization of adenosine 1r (1, R = ribose), guanosine 2r, and deoxycytidine 3d (3, R = deoxyribose) and their fragmentations were studied with tandem mass spectrometry. In contrast to previous EI-MS studies of the nucleobases, NH3 elimination does present a major path for the fragmentations of the ions [1h + H]+, [2h + H]+, and …

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A Cosmic Ray Current-Driven Instability In Partially Ionised Media, Brian Reville, John Kirk, Peter Duffy, Stephen O'Sullivan Nov 2007

A Cosmic Ray Current-Driven Instability In Partially Ionised Media, Brian Reville, John Kirk, Peter Duffy, Stephen O'Sullivan

Articles

We investigate the growth of hydromagnetic waves driven by streaming cosmic rays in the precursor environment of a supernova remnant shock. It is known that transverse waves propagating parallel to the mean magnetic field are unstable to anisotropies in the cosmic ray distribution, and may provide a mechanism to substantially amplify the ambient magnetic field. We quantify the extent to which temperature and ionisation fractions modify this picture. Using a kinetic description of the plasma we derive the dispersion relation for a collisionless thermal plasma with a streaming cosmic ray current. Fluid equations are then used to discuss the effects …

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Tidal Flushing Characteristics In Virginia’S Tidal Embayments, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Julie Herman, Jian Shen, Jie Huang Nov 2007

Tidal Flushing Characteristics In Virginia’S Tidal Embayments, Center For Coastal Resources Management, Virginia Institute Of Marine Science, Julie Herman, Jian Shen, Jie Huang

Reports

This project evaluated water bodies in the Virginia coastal zone using several water quality models to calculate residence times. Results were grouped into tidal flushing categories (quickly, intermediately, and slowly flushed) that reflect a relative time frame in which a water body is flushed.

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Problem Solving And Proving Via Generalisation, Michael De Villiers, Mary Garner Nov 2007

Problem Solving And Proving Via Generalisation, Michael De Villiers, Mary Garner

Faculty and Research Publications

No abstract provided.

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The Case For Optically Thick High-Velocity Broad-Line Region Gas In Active Galactic Nuclei, Stephanie A. Snedden, C. Martin Gaskell Nov 2007

The Case For Optically Thick High-Velocity Broad-Line Region Gas In Active Galactic Nuclei, Stephanie A. Snedden, C. Martin Gaskell

C. Martin Gaskell Publications

A combined analysis of the profiles of the main broad quasar emission lines in both Hubble Space Telescope and optical spectra shows that while the profiles of the strong UV lines are quite similar, there is frequently a strong increase in the Lyα/Hα ratio in the high-velocity gas.We show that the suggestion that the high-velocity gas is optically thin presents many problems.We show that the relative strengths of the high-velocity wings arise naturally in an optically thick BLR component. An optically thick model successfully explains the equivalent widths of the lines, the Lyα/Hα ratios and flatter Balmer decrements in the …

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Agn Reddening And Ultraviolet Extinction Curves From Hubble Space Telescope Spectra, C. Martin Gaskell, C. Martin Gaskell Nov 2007

Agn Reddening And Ultraviolet Extinction Curves From Hubble Space Telescope Spectra, C. Martin Gaskell, C. Martin Gaskell

C. Martin Gaskell Publications

We present intrinsic extinction curves for 14 AGNs. The AGNs have reddenings, E(B-V), of up to 0.36 mag. The majority (13 out of 14) of the extinction curves are not steep in the UV. Of the seven best determined extinction curves, five have extinction curves that are as flat as the standard Galactic curve in the optical and near UV, but flatter in the far UV, and without the λ2175 feature. One AGN, B3 0754+394, has a steep SMC-like extinction curve, and another, Mrk 304, has an LMC-like extinction curve, including a probable λ2175 bump. The remaining seven, lower-quality, extinction …

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Discovery Of Polarization Reverberation In Ngc 4151, C. Martin Gaskell, René W. Goosmann, Nelly I. Merkulova, Nikolay M. Shakhovskoy, Masatoshi Shoji Nov 2007

Discovery Of Polarization Reverberation In Ngc 4151, C. Martin Gaskell, René W. Goosmann, Nelly I. Merkulova, Nikolay M. Shakhovskoy, Masatoshi Shoji

C. Martin Gaskell Publications

Observations of the optical polarization of NGC 4151 in 1997–2003 show variations of an order of magnitude in the polarized flux while the polarization position angle remains constant. The amplitude of variability of the polarized flux is comparable to the amplitude of variability of the total U-band flux, except that the polarized flux follows the total flux with a lag of 8±3 days. The time lag and the constancy of the position angle strongly favor a scattering origin for the variable polarization rather than a non-thermal synchrotron origin. The orientation of the position angle of the polarized flux (parallel to …

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Ngc 5548: The Agn Energy Budget Problem And The Geometry Of The Broad-Line Region And Torus, C. Martin Gaskell, Elizabeth S. Klimek, Ludmila S. Nazarova Nov 2007

Ngc 5548: The Agn Energy Budget Problem And The Geometry Of The Broad-Line Region And Torus, C. Martin Gaskell, Elizabeth S. Klimek, Ludmila S. Nazarova

C. Martin Gaskell Publications

We consider in detail the spectral energy distribution (SED) and multi-wavelength variability of NGC 5548. Comparison with the SEDs of other AGNs implies that the internal reddening of NGC 5548 is E(B-V) = 0.17 mag. The extinction curve is consistent with the mean curve of other AGNs found by Gaskell & Benker, but inconsistent with an SMC-type reddening curve. Because most IR emission originates exterior to the broad-line region (BLR), the SED seen by the inner BLR is different from that seen by the outer BLR and from the earth. The most likely BLR covering factor is ~ 40% and …

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Transformations Between 2mass, Sdss And Bvri Photometric Systems: Bridging The Near Infrared And Optical, S. Bilir, S. Ak, S. Karaali, A. Cabrera-Lavers, T. S. Chonis, C. Martin Gaskell Nov 2007

Transformations Between 2mass, Sdss And Bvri Photometric Systems: Bridging The Near Infrared And Optical, S. Bilir, S. Ak, S. Karaali, A. Cabrera-Lavers, T. S. Chonis, C. Martin Gaskell

C. Martin Gaskell Publications

We present color transformations for the conversion of the 2MASS photometric system to the Johnson-Cousins UBV RI system and further into the SDSS ugriz system. We have taken SDSS gri magnitudes of stars measured with the 2.5-m telescope from SDSS Data Release 5 (DR5), and BV RI and JHKs magnitudes from Stetson’s catalogue and Cutri et al. (2003), respectively. We matched thousands of stars in the three photometric systems by their coordinates and obtained a homogeneous sample of 825 stars by the following constraints, which are not used in previous transformations: 1) the data are de-reddened, 2) giants are …

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Half Metallic Ferromagnets, Peter A. Dowben Nov 2007

Half Metallic Ferromagnets, Peter A. Dowben

Peter Dowben Publications

Since its introduction by de Groot and colleagues in the early 1980s [1], the concept of half metallic ferromagnetism has attracted great interest. Idealized, half-metals have only one spin channel for conduction: the spin-polarized band structure exhibits metallic behavior for one spin channel, while the other spin band structure exhibits a gap at the Fermi level. Due to the gap for one spin direction, the density of states at the Fermi level has, theoretically, 100 % spin polarization. This gap in the density of states in one spin at the Fermi level, for example ↓ so N↓(EF …

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Designing The Market Game For A Commodity Trading Simulation, Shih-Fen Cheng Nov 2007

Designing The Market Game For A Commodity Trading Simulation, Shih-Fen Cheng

Research Collection School Of Computing and Information Systems

In this paper, we propose to design a market game that (a) can be used in modeling and studying commodity trading scenarios, and (b) can be used in capturing human traders' behaviors. Specifically, we demonstrate the usefulness of this commodity trading game in a single-commodity futures trading scenario. A pilot experiment was run with a mixture of human traders and an autonomous agent that emulates the aggregatedmarket condition, with the assumption that this autonomous agent would hint each of its action through a public announcement. We show that the information collected from this simulation can be used to extract the …

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