96 research outputs found
Ontologies as bridges between data sources and user queries: the KNOWMAK project experience
This paper describes ongoing work in the KNOWMAK project, which aims to develop a webbased
tool providing interactive visualisations and state-of-the-art indicators on knowledge cocreation
in the European research area. One of the main novel developments in this work is the
use of ontologies to act as a bridge between the data sources (research projects, patents and
publications) and user queries, in order to address the problems of mapping between
heterogenous data sources with different vocabularies while still maintaining a level of
standardization necessary for summarising the information required to provide informative
views about the highly dynamic S&T landscape
Sulphur deficiency in rapeseed – diagnostic plant analysis
Non-Peer Reviewe
Who cares about sarcastic tweets? Investigating the impact of sarcasm on sentiment analysis
Sarcasm is a common phenomenon in social media, and is inherently difficult to analyse, not just automatically but often for humans
too. It has an important effect on sentiment, but is usually ignored in social media analysis, because it is considered too tricky to handle.
While there exist a few systems which can detect sarcasm, almost no work has been carried out on studying the effect that sarcasm has on
sentiment in tweets, and on incorporating this into automatic tools for sentiment analysis. We perform an analysis of the effect of sarcasm
scope on the polarity of tweets, and have compiled a number of rules which enable us to improve the accuracy of sentiment analysis when
sarcasm is known to be present. We consider in particular the effect of sentiment and sarcasm contained in hashtags, and have developed
a hashtag tokeniser for GATE, so that sentiment and sarcasm found within hashtags can be detected more easily. According to our experiments,
the hashtag tokenisation achieves 98% Precision, while the sarcasm detection achieved 91% Precision and polarity detection 80%
Challenges of Evaluating Sentiment Analysis Tools on Social Media
This paper discusses the challenges in carrying out fair comparative evaluations of sentiment analysis systems. Firstly, these are due to
differences in corpus annotation guidelines and sentiment class distribution. Secondly, different systems often make different assumptions
about how to interpret certain statements, e.g. tweets with URLs. In order to study the impact of these on evaluation results, this paper
focuses on tweet sentiment analysis in particular. One existing and two newly created corpora are used, and the performance of four
different sentiment analysis systems is reported; we make our annotated datasets and sentiment analysis applications publicly available.
We see considerable variations in results across the different corpora, which calls into question the validity of many existing annotated
datasets and evaluations, and we make some observations about both the systems and the datasets as a result
An Investigation of the Soft Pion Relation in Quenched Lattice QCD
A lattice determination of the form factor and decay constants for the
semileptonic decay of heavy pseudoscalar (PS) mesons at zero recoil is
presented from which the soft pion relation is satisfied. Chiral extrapolation
of the form factor is performed at constant . Pole dominance is used to
extrapolate the form factor in heavy quark mass. At the B mass, the form factor
at zero recoil lies somewhat below the ratio of decay constants; the relation
remains satisfied within error.Comment: 3 pages, 2 figure
Excited nucleon spectrum using a non-perturbatively improved clover fermion action
We discuss the extraction of negative-parity baryon masses from lattice QCD
calculations. The mass of the lowest-lying negative-parity state
is computed in quenched lattice QCD using an -improved clover
fermion action, and a splitting found with the nucleon mass. The calculation is
performed on two lattice volumes, and three lattice spacings enabling a study
of both finite-volume and finite-lattice-spacing uncertainties. A measurement
of the first excited radial excitation of the nucleon finds a mass considerably
larger than that of the negative-parity ground state, in accord with other
lattice determinations but in disagreement with experiment. Results are also
presented for the lightest negative-parity state.Comment: 7 pages, 5 figures, uses espcrc2. Talk presented at Workshop on
Lattice Hadron Physics, Colonial Club Resort, Cairns, Australia, July 9-18,
2001. Corrected error in determination of mass of excited, positive-parity
nucleon resonanc
Negative-parity Baryon Masses using an O(a)-improved Fermion Action
We present a calculation of the mass of the lowest-lying negative-parity
J=1/2- state in quenched QCD. Results are obtained using a non-perturbatively
O(a)-improved clover fermion action, and a splitting is found between the mass
of the nucleon and its parity partner. The calculation is performed on two
lattice volumes and at three lattice spacings, enabling a study of both
finite-volume and finite lattice-spacing uncertainties. A comparison is made
with results obtained using the unimproved Wilson fermion action.Comment: 13 pages, 8 figures, revtex Version accepted for publication in
Physics Letters B. Some changes to discussion of chiral extrapolations;
primary results unchange
Experimental support of the scaling rule for demographic stochasticity
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73613/1/j.1461-0248.2006.00903.x.pd
First observation of the decay and a measurement of the ratio of branching fractions
The first observation of the decay using
data collected by the LHCb detector at a centre-of-mass energy of 7 TeV,
corresponding to an integrated luminosity of 36 pb, is reported. A
signal of events is obtained and the absence of signal is
rejected with a statistical significance of more than nine standard deviations.
The branching fraction is measured relative to
that of : , where the first uncertainty is statistical, the second systematic and
the third is due to the uncertainty on the ratio of the and
hadronisation fractions.Comment: 10 pages, 3 figures, submitted to Phys. Lett. B; ISSN 0370-269
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