2,077 research outputs found
An Analysis of Subject Coverage and Worldwide Involvement of E-LIS: the International Repository for Library and Information Science.
E-LIS, E-prints for Library and Information Science, is a subject-oriented repository initiated in January 2003 by a group of European information specialists. E-LIS is an open-access repository run by experts and editors from many different countries and with holdings originating in 110 countries. The first purpose of this study is to provide a description of E-LIS with special attention to the types of documents archived and the geographical distribution of its contributors. The second purpose is to determine the subject coverage, which is done by using several well-known bibliometric techniques. Using co-occurrences of subject terms, a cluster analysis is performed, producing four major clusters; a correspondence analysis of keywords and subject terms produces eight groups of association
Inside Science Resources in Retrospective – 2015 – 2020
The purpose of this report is threefold: 1. To summarize the production of the committee since its beginning in April of 2015; 2. To give credit to all the contributors for their excellent work in identifying resources of value to the STEM community; and 3. To provide an easy index for all the contributions made. A total of 63 contributions have been published in this blog, which have been written by 30 of our STS colleagues
MgII absorption systems with W_0 > 0.1 \AA for a radio selected sample of 77 QSOs and their associated magnetic fields at high redshifts
We present a catalogue of MgII absorption systems obtained from high
resolution UVES/VLT data of 77 QSOs in the redshift range 0.6 < z < 2.0, and
down to an equivalent width W_0 > 0.1 \AA. The statistical properties of our
sample are found to be in agreement with those from previous work in the
literature. However, we point out that the previously observed increase with
redshift of dN/dz for weak absorbers, pertains exclusively to very weak
absorbers with W_0 < 0.1 \AA. Instead, dN/dz for absorbers with W_0 in the
range 0.1-0.3 \AA actually decreases with redshift, similarly to the case of
strong absorbers. We then use this catalogue to extend our earlier analysis of
the links between the Faraday Rotation Measure of the quasars and the presence
of intervening MgII absorbing systems in their spectra. In contrast to the case
with strong MgII absorption systems W_0 > 0.3 \AA, the weaker systems do not
contribute significantly to the observed Rotation Measure of the background
quasars. This is possibly due to the higher impact parameters of the weak
systems compared to strong ones, suggesting that the high column density
magnetized material that is responsible for the Faraday Rotation is located
within about 50 kpc of the galaxies. Finally, we show that this result also
rules out the possibility that some unexpected secondary correlation between
the quasar redshift and its intrinsic Rotation Measure is responsible for the
association of high Rotation Measure and strong intervening MgII absorption
that we have presented elsewhere, since this would have produced an equal
effect for the weak absorption line systems, which exhibit a very similar
distribution of quasar redshifts.Comment: Accepted for publication in ApJ. 12 pages, 8 figure
AAMQS: a non-linear QCD description of new HERA data at small-x
We present a global analysis of available data on inclusive structure
functions measured in electron-proton scattering at small values of Bjorken-x,
including the latest data from the combined HERA analysis on reduced cross
sections. Our approach relies on the dipole formulation of DIS together with
the use of the non-linear running coupling BK equation for the description of
the small-x dynamics. With the resulting parametrization we are able to
describe the latest FL data measured by the H1 collaboration. Further, we
discuss the kinematical domain where significant deviations from NLO-DGLAP
should be expected and the ability of non-linnear physics to account for such
deviations.Comment: 4 pages, 2 figures, Proceedings of Quark Matter 2011, Annecy, Franc
Ferromagnetic bubble clusters in YCaMnO thin films
We studied the ferromagnetic topology in a YCaMnO thin
film with a combination of magnetic force microscopy and magnetization
measurements. Our results show that the spin-glass like behavior, reported
previously for this system, could be attributed to frustrated interfaces of the
ferromagnetic clusters embedded in a non-ferromagnetic matrix. We found
temperature dependent changes of the magnetic topology at low temperatures,
which suggests a non-static Mn/Mn ratio
A predictive phenomenological tool at small Bjorken-x
We present the results from global fits of inclusive DIS experimental data
using the Balitsky-Kovchegov equation with running coupling.Comment: 5 pages, 2 figures, prepared for the Proceedings of 'Hot Quarks 2010
A Visualization Model Used for Determining the Effectiveness of Information Retrieval in a Scientific Database
In this study, we demonstrate that a visualization model can determine the effectiveness of searching a bibliographic database, when three descriptive metadata fields are compared. The Inspec database was searched to create a bibliography of articles about a broad scientific topic, interplanetary travel. We collected metadata from 823 Inspec articles and used the Sci2 Tool to create co-occurrence networks based on subject terms, title keywords, and classification codes from each of the articles. The Watts-Strogatz clustering coefficient model was used to create molecular organization of the networks. This method identified subject domain clusters for each of the three selected metadata elements and subject classification codes were extracted from all the clusters obtained. All data obtained was converted into a common metadata element (classification codes), allowing for the comparison of data from the initial search and from all the subject clusters identified in the visualization process. A set of eight subject codes were found to describe the Main Subject Domain of interplanetary travel. The results also show that searching with classification codes produced the best outcome, the second best option is using subject terms, and the least effective search technique is using title keywords. These results, using visualization, corroborate previous studies
Forage and weed species and grazing management systems on permanent pastures in the Allegheny Highlands of West Virginia
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