6,116 research outputs found
On gauged linear sigma models with torsion
We study a broad class of two dimensional gauged linear sigma models (GLSMs)
with off-shell N=(2,2) supersymmetry that flow to nonlinear sigma models
(NLSMs) on noncompact geometries with torsion. These models arise from coupling
chiral, twisted chiral, and semichiral multiplets to known as well as to a new
N=(2,2) vector multiplet, the constrained semichiral vector multiplet (CSVM).
We discuss three kinds of models, corresponding to torsionful deformations of
standard GLSMs realizing Kahler, hyperkahler, and Calabi-Yau manifolds. The
(2,2) supersymmetry guarantees that these spaces are generalized Kahler. Our
analysis of the geometric structure is performed at the classical level, but we
also discuss quantum aspects such as R-symmetry anomalies. We provide an
explicit example of a generalized Kahler structure on the conifold.Comment: 39 pages, 1 figure. v2: References adde
Satisfying states of triangulations of a convex n-gon
In this work we count the number of satisfying states of triangulations of a
convex n-gon using the transfer matrix method. We show an exponential (in n)
lower bound. We also give the exact formula for the number of satisfying states
of a strip of triangles.Comment: 17 pages, 6 figure
Finite Size Effect in Persistence
We have investigated the random walk problem in a finite system and studied
the crossover induced in the the persistence probability scales by the system
size.Analytical and numerical work show that the scaling function is an
exponentially decaying function.The particle here is trapped with in a box of
size . We have also considered the problem when the particle in trapped in
a potential. Direct calculation and numerical result show that the scaling
function here also an exponentially decaying function. We also present
numerical works on harmonically trapped randomly accelerated particle and
randomly accelerated particle with viscous drag.Comment: revtex4, 4 pages, 4 figure
Reediting the war in Asia: Japanese newsreels in Spain (1931-1945)
During the fifteen-year conflict in Asia (1931-1945), the Japanese industry of newsreels experienced ad extraordinary growth, prompted by the incidents in China in the thirties and by the propaganda needs particularly from 1940, when all news films were fused in Nippon News. The images on Asia seen in Spanish cinemas had been originated in the Japanese newsreels, at least until the last stage of the Pacific War. To a great extent, they reached Spain as versions of Nazi Germany’s newsreel Auslandstonwoche, but there were also other sources. This article seeks to cast light on the impact that the Japanese newsreel industry had on Spain, tracing how these images circulated and determine how they conditioned the local reception of the events in Asia
Characterization of vertical electric fields and associated voltages induced on a overhead power line from close artificially initiated lightning
Measurements were characterized of simultaneous vertical electric fields and voltages induced at both ends of a 448 m overhead power line by artificially initiated lightning return strokes. The lightning discharges struck ground about 20 m from one end of the line. The measured line voltages could be grouped into two categories: those in which multiple, similarly shaped, evenly spaced pulses were observed, which are called oscillatory; and those dominated by a principal pulse with subsidiary oscillations of much smaller amplitude, which are called impulsive. Voltage amplitudes range from tens of kilovolts for oscillatory voltages to hundreds of kilovolts for impulsive voltages
NCBO Ontology Recommender 2.0: An Enhanced Approach for Biomedical Ontology Recommendation
Biomedical researchers use ontologies to annotate their data with ontology
terms, enabling better data integration and interoperability. However, the
number, variety and complexity of current biomedical ontologies make it
cumbersome for researchers to determine which ones to reuse for their specific
needs. To overcome this problem, in 2010 the National Center for Biomedical
Ontology (NCBO) released the Ontology Recommender, which is a service that
receives a biomedical text corpus or a list of keywords and suggests ontologies
appropriate for referencing the indicated terms. We developed a new version of
the NCBO Ontology Recommender. Called Ontology Recommender 2.0, it uses a new
recommendation approach that evaluates the relevance of an ontology to
biomedical text data according to four criteria: (1) the extent to which the
ontology covers the input data; (2) the acceptance of the ontology in the
biomedical community; (3) the level of detail of the ontology classes that
cover the input data; and (4) the specialization of the ontology to the domain
of the input data. Our evaluation shows that the enhanced recommender provides
higher quality suggestions than the original approach, providing better
coverage of the input data, more detailed information about their concepts,
increased specialization for the domain of the input data, and greater
acceptance and use in the community. In addition, it provides users with more
explanatory information, along with suggestions of not only individual
ontologies but also groups of ontologies. It also can be customized to fit the
needs of different scenarios. Ontology Recommender 2.0 combines the strengths
of its predecessor with a range of adjustments and new features that improve
its reliability and usefulness. Ontology Recommender 2.0 recommends over 500
biomedical ontologies from the NCBO BioPortal platform, where it is openly
available.Comment: 29 pages, 8 figures, 11 table
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