10,682 research outputs found
Revisiting the Roman domus in Rabat, Malta, through a consideration of its mosaic flooring
Mosaics have a language of their own. Whether they exhibit figurative or geometric drawings, mosaics
help to regulate the flow of movement within a building and often correspond to the function of rooms.
Figurative mosaics were meant to be admired and discussed by the pater familias and his guests,
whilst geometric mosaics decorated passage areas that did not require waiting, such as corridors and
service areas. Floor mosaics can offer valuable insights into the spatial organisation within a house.
This paper considers the floor mosaics of the Roman domus in Rabat, Malta, and explores how their
direction, decoration, and arrangement can help to gain a better understanding of the internal layout
of the house.peer-reviewe
Involutory reflection groups and their models
A finite subgroup of is involutory if the sum of the
dimensions of its irreducible complex representations is given by the number of
absolute involutions in the group. A uniform combinatorial model is constructed
for all non-exceptional irreducible complex reflection groups which are
involutory including, in particular, all infinite families of finite
irreducible Coxeter groups.Comment: 24 page
Italian Event Detection Goes Deep Learning
This paper reports on a set of experiments with different word embeddings to
initialize a state-of-the-art Bi-LSTM-CRF network for event detection and
classification in Italian, following the EVENTI evaluation exercise. The net-
work obtains a new state-of-the-art result by improving the F1 score for
detection of 1.3 points, and of 6.5 points for classification, by using a
single step approach. The results also provide further evidence that embeddings
have a major impact on the performance of such architectures.Comment: to appear at CLiC-it 201
Diagonal invariants and the refined multimahonian distribution
Combinatorial aspects of multivariate diagonal invariants of the symmetric
group are studied. As a consequence it is proved the existence of a
multivariate extension of the classical Robinson-Schensted correspondence.
Further byproduct are a pure combinatorial algorithm to describe the
irreducible decomposition of the tensor product of two irreducible
representations of the symmetric group, and new symmetry results on permutation
enumeration with respect to descent sets.Comment: 18 page
Signed mahonians on some trees and parabolic quotients
We study the distribution of the major index with sign on some parabolic
quotients of the symmetric group, extending and generalizing simultaneously
results Gessel-Simion and Adin-Gessel-Roichman, and on some special trees that
we call rakes. We further consider and compute the distribution of the
flag-major index on some parabolic quotients of wreath products and other
related groups. All these distributions turn out to have very simple
factorization formulas.Comment: 12 page
Chemistry and kinematics of the pre-stellar core L1544: Constraints from H2D+
This paper explores the sensitivity of line profiles of H2D+, HCO+ and N2H+,
observed towards the center of L1544, to various kinematic and chemical
parameters. The total width of the H2D+ line can be matched by a static model
and by models invoking ambipolar diffusion and gravitational collapse. The
derived turbulent line width is b=0.15 km/s for the static case and <~ 0.05
km/s for the collapse case. However, line profiles of HC18O+ and N2H+ rule out
the static solution. The double-peaked H2D+ line shape requires either infall
speeds in the center that are much higher than predicted by ambipolar diffusion
models, or a shell-type distribution of H2D+, as is the case for HCO+ and N2H+.
At an offset of ~20 arcsec from the dust peak, the H2D+ abundance drops by a
factor of ~5.Comment: four pages, two colour figures; to appear in The Dense Interstellar
Medium in Galaxies, proceedings of the fourth Cologne-Bonn-Zermatt Symposium,
Sept 22-26, 200
Accounting for Cross-Country Income Differences
Why are some countries so much richer than others? Development Accounting is a first-pass attempt at organizing the answer around two proximate determinants: factors of production and efficiency. It answers the question "how much of the cross-country income variance can be attributed to differences in (physical and human) capital, and how much to differences in the efficiency with which capital is used?" Hence, it does for the cross-section what growth accounting does in the time series. The current consensus is that efficiency is at least as important as capital in explaining income differences. I survey the data and the basic methods that lead to this consensus, and explore several extensions. I argue that some of these extensions may lead to a reconsideration of the evidence.
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