24,517 research outputs found
Student user preferences for features of next-generation OPACs: a case study of University of Sheffield international students
Purpose. The purpose of this study is to identity the features that international student users prefer for next generation OPACs.
Design/ methodology/ approach. 16 international students of the University of Sheffield were interviewed in July 2008 to explore their preferences among potential features in next generation OPACs. A semi-structured interview schedule with images of mock-up screens was used.
Findings. The results of the interviews were broadly consistent with previous studies. In general, students expect features in next generation OPACs should be save their time, easy to use and relevant to their search. This study found that recommender features and features that can provide better navigation of search results are desired by users. However, Web 2.0 features, such as RSS feeds and those features which involved user participation were among the most popular.
Practical implications. This paper produces findings of relevance to any academic library seeking to implement a next-generation OPAC.
Originality/value. There have been no previous published research studies of users’ preferences among possible features of next-generation OPACs
Complex organic molecules in the interstellar medium: IRAM 30 m line survey of Sagittarius B2(N) and (M)
The discovery of amino acids in meteorites and the detection of glycine in
samples returned from a comet to Earth suggest that the interstellar chemistry
is capable of producing such complex organic molecules. Our goal is to
investigate the degree of chemical complexity that can be reached in the ISM.
We performed an unbiased, spectral line survey toward Sgr B2(N) and (M) with
the IRAM 30m telescope in the 3mm window. The spectra were analyzed with a
simple radiative transfer model that assumes LTE but takes optical depth
effects into account. About 3675 and 945 spectral lines with a peak
signal-to-noise ratio higher than 4 are detected toward N and M, i.e. about 102
and 26 lines per GHz, respectively. This represents an increase by about a
factor of 2 over previous surveys of Sgr B2. About 70% and 47% of the lines
detected toward N and M are identified and assigned to 56 and 46 distinct
molecules as well as to 66 and 54 less abundant isotopologues of these
molecules, respectively. We also report the detection of transitions from 59
and 24 catalog entries corresponding to vibrationally or torsionally excited
states of some of these molecules, respectively. Excitation temperatures and
column densities were derived for each species but should be used with caution.
Among the detected molecules, aminoacetonitrile, n-propyl cyanide, and ethyl
formate were reported for the first time in space based on this survey, as were
5 rare isotopologues of vinyl cyanide, cyanoacetylene, and hydrogen cyanide. We
also report the detection of transitions from within 12 new vib. or tors.
excited states of known molecules. Although the large number of unidentified
lines may still allow future identification of new molecules, we expect most of
these lines to belong to vib. or tors. excited states or to rare isotopologues
of known molecules for which spectroscopic predictions are currently missing.
(abridged)Comment: Accepted for publication in A&A. 266 pages (39 pages of text), 111
tables, 8 figure
Engaging students with mobile web2.0.
Abstract: Blogs, wikis, podcasting, and a host of free, easy to use web2.0 social software provide opportunities for creating social constructivist learning environments focusing upon student-centred learning and end-user content creation and sharing. Building on this foundation, mobile web2.0 has emerged as a viable teaching and learning environment, particularly with the advent of the iPhone (Nicknamed “the Jesus phone” (Goldman, 2007)) and iPod Touch. Today’s wifi enabled smartphones provide a ubiquitous connection to mobile web2.0 social software and the ability to view, create, edit and upload user generated web2.0 content. This paper outlines how mobile web2.0 technologies can be harnessed to enhance and engage students in a social constructivist learning environment. Examples of student and teaching staff feedback are drawn from several mobile learning trials that have been conducted at Unitec New Zealand. Additionally the presentation will involve mobile web2.0 demonstrations and facilitate a discussion around the practicalities of integrating and supporting mobile web2.0 within a tertiary course
Galaxy Genesis -- unravelling the epoch of dissipation in the early disk
So how did the Galactic disk form and can the sequence of events ever be
unravelled from the vast stellar inventory? This will require that some of the
residual inhomogeneities from prehistory escaped the dissipative process at an
early stage. Fossil hunting to date has concentrated mostly on the stellar
halo, but a key source of information will be the thick disk. This is believed
to be a 'snap frozen' relic which formed during or shortly after the last major
epoch of dissipation, or it may have formed from infalling systems early in the
life of the Galaxy. As part of the KAOS Galaxy Genesis project, we explore the
early history of the halo and the thick disk by looking for discrete
substructures, either due to infall or in situ star formation, through chemical
tagging. This will require high signal to noise, echelle spectroscopy of up to
a million stars throughout the disk. Our program has a short-term and a
long-term goal.Comment: 5th Workshop on Galaxy Chemodynamics, eds. B.K. Gibson, D. Kawata;
PASA, accepted (11 pages, 6 GIF figures, 3 style files
Quantitative chemical tagging, stellar ages and the chemo-dynamical evolution of the Galactic disc
The early science results from the new generation of high-resolution stellar
spectroscopic surveys, such as GALAH and the Gaia-ESO survey, will represent
major milestones in the quest to chemically tag the Galaxy. Yet this technique
to reconstruct dispersed coeval stellar groups has remained largely untested
until recently. We build on previous work that developed an empirical chemical
tagging probability function, which describes the likelihood that two field
stars are conatal, that is, they were formed in the same cluster environment.
In this work we perform the first ever blind chemical tagging experiment, i.e.,
tagging stars with no known or otherwise discernable associations, on a sample
of 714 disc field stars with a number of high quality high resolution
homogeneous metal abundance measurements. We present evidence that chemical
tagging of field stars does identify coeval groups of stars, yet these groups
may not represent distinct formation sites, e.g. as in dissolved open clusters,
as previously thought. Our results point to several important conclusions,
among them that group finding will be limited strictly to chemical abundance
space, e.g. stellar ages, kinematics, colors, temperature and surface gravity
do not enhance the detectability of groups. We also demonstrate that in
addition to its role in probing the chemical enrichment and kinematic history
of the Galactic disc, chemical tagging represents a powerful new stellar age
determination technique.Comment: 12 pages, 9 figures, accepted for publication in Monthly Notices of
the Royal Astronomical Society (MNRAS
NASA Global Atmospheric Sampling Program (GASP) data report for tapes VL0007 and VL0008
The Global Atmospheric Sampling Program (GASP) is obtaining measurements of atmospheric trace constituents in the upper troposphere and lower stratosphere using fully automated air sampling systems on board the NASA CV-990 research aircraft and four commerical B-747 aircraft in routine airline service. In-situ measurements of atmospheric ozone and water vapor, data from laboratory analysis of filters exposed in flight, and related flight and meteorological data obtained from September 1976 through January 1977 are reported. These data are now available on GASP tapes VL0007 & VL0008 from the National Climatic Center, Asheville, North Carolina. In addition to the GASP data, tropopause pressure fields obtained from NMC archives for the dates of the GASP flights are included on the data tape. Flight routes and dates, instrumentation, data processing procedures, and data tape specifications are described
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