98 research outputs found
Faster Wasserstein Distance Estimation with the Sinkhorn Divergence
The squared Wasserstein distance is a natural quantity to compare probability
distributions in a non-parametric setting. This quantity is usually estimated
with the plug-in estimator, defined via a discrete optimal transport problem
which can be solved to -accuracy by adding an entropic regularization
of order and using for instance Sinkhorn's algorithm. In this work,
we propose instead to estimate it with the Sinkhorn divergence, which is also
built on entropic regularization but includes debiasing terms. We show that,
for smooth densities, this estimator has a comparable sample complexity but
allows higher regularization levels, of order , which leads to
improved computational complexity bounds and a strong speedup in practice. Our
theoretical analysis covers the case of both randomly sampled densities and
deterministic discretizations on uniform grids. We also propose and analyze an
estimator based on Richardson extrapolation of the Sinkhorn divergence which
enjoys improved statistical and computational efficiency guarantees, under a
condition on the regularity of the approximation error, which is in particular
satisfied for Gaussian densities. We finally demonstrate the efficiency of the
proposed estimators with numerical experiments
Hybrid MIMD/SIMD High Order DGTD Solver for the Numerical Modeling of Light/Matter Interaction on the Nanoscale
International audienceThis paper is concerned with the development of a scalable high order finite element type solver for the numerical modeling of light interaction with nanometer scale structures. From the mathematical modeling point of view, one has to deal with the differential system of Maxwell equations in the time domain, coupled to an appropriate differential model of the behavior of the underlying material (which can be a dielectric and/or a metal) at optical frequencies. For the numerical solution of the resulting system of differential equations, we have designed a high order DGTD (Discontinuous Galerkin Time-Domain) solver that has been adapted to hybrid MIMD/SIMD computing. Here we discuss about this later aspect and report on preliminary performance results on the Curie system of the PRACE research infrastructure
The blind spots of secularization
According to several international surveys Spain is among the western countries with the most negative views of Jews. While quantitative data on the topic accumulates, there is a significant lack of interpretative approaches that might explain the particular Spanish case. This paper presents the background, methodology and major results of a discussion group-based study on antisemitism, which was conducted in Spain in the autumn of 2009. The study identifies and locates in different socio-economic and ideological milieus the range of stereotypical discourses on Jews, Judaism and the Arab–Israeli conflict in Spain. Analysis of the group meetings shows that, despite growing secularization in Spanish society, the central explanatory variable for persisting and resurging antisemitism in this country is still religion in a broad cultural sense.Peer reviewe
ISO observations of 3 - 200 micron emission by three dust populations in an isolated local translucent cloud
We present ISOPHOT spectrophotometry of three positions within the isolated
high latitude cirrus cloud G 300.2 - 16.8, spanning from the near- to
far-infrared. The positions exhibit contrasting emission spectrum contributions
from the UIBs, very small grains and large classical grains, and both
semi-empirical and numerical models are presented. At all three positions, the
UIB spectrum shapes are found to be similar, and the large grain emission may
be fitted by an equilibrium temperature of ~17.5 K. The energy requirements of
both the observed emission spectrum and optical scattered light are shown to be
satisfied by the incident local ISRF. The FIR emissivity of dust in G 300.2 -
16.8 is found to be lower than in globules or dense clouds, and is even lower
than model predictions for dust in the diffuse ISM. The results suggest
physical differences in the ISM mixtures between positions within the cloud,
possibly arising from grain coagulation processes.Comment: 22 pages, 8 tables, 11 figures (figure 8 is in colour). Landscape
table included as separate LaTeX file. Accepted for publication in MNRA
Case report: Neuronal intranuclear inclusion disease presenting with acute encephalopathy
Neuronal intranuclear inclusion disease (NIID), a neurodegenerative disease previously thought to be rare, is increasingly recognized despite heterogeneous clinical presentations. NIID is pathologically characterized by ubiquitin and p-62 positive intranuclear eosinophilic inclusions that affect multiple organ systems, including the brain, skin, and other tissues. Although the diagnosis of NIID is challenging due to phenotypic heterogeneity, a greater understanding of the clinical and imaging presentations can improve accurate and early diagnosis. Here, we present three cases of pathologically proven adult-onset NIID, all presenting with episodes of acute encephalopathy with protracted workups and lengthy time between symptom onset and diagnosis. Case 1 highlights challenges in the diagnosis of NIID when MRI does not reveal classic abnormalities and provides a striking example of hyperperfusion in the setting of acute encephalopathy, as well as unique pathology with neuronal central chromatolysis, which has not been previously described. Case 2 highlights the progression of MRI findings associated with multiple NIID-related encephalopathic episodes over an extended time period, as well as the utility of skin biopsy for antemortem diagnosis
Altimetry for the future: Building on 25 years of progress
In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the ‘‘Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion
Altimetry for the future: building on 25 years of progress
In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology.
The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the “Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion
O cômputo de valores destinados à alimentação escolar para fins de cálculo do percentual constitucional referente à aplicação de recursos em manutenção e desenvolvimento do ensino
Analisa se os valores destinados à alimentação escolar devem ser computados para o cálculo do índice constitucional de educação
Motions de MM. Papin et Christin concernant les pièces destinées à la fabrication des assignats, lors de la séance du 31 mars 1791
Papin Léger, Christin Charles Gabriel. Motions de MM. Papin et Christin concernant les pièces destinées à la fabrication des assignats, lors de la séance du 31 mars 1791. In: Archives Parlementaires de 1787 à 1860 - Première série (1787-1799) Tome XXIV - Du 10 mars 1791 au 12 avril 1791. Paris : Librairie Administrative P. Dupont, 1886. pp. 474-475
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