Quatre indicateurs d'inflation sous-jacente: application et interpretation.

Dans ce papier, nous comparons quatre indicateurs de l'inflation sous-jacente: l'approche par exclusion de postes, les estimateurs "a influence limitee" comme l'inflation mediane, les mesures issues d'un VAR structurel et une mesure tiree d'un modele a composantes inobservables. Ces indicateurs sont discutes du point de vue de leur interpretation et de leur utilisation a des fins conjoncturelles.Econometrie ; Inflation ; Instruments de mesure

Modelisation et prevision des indices de prix sectoriels.

Ce papier presente une modelisation de l'indice des prix francais. L'objectif est de permettre une analyse rapide et detaillee des tendances de court terme de l'inflation ainsi que de realiser des previsions a intervalles rapproches. Les caracteristiques de cet outil sont les suivantes: un petit nombre d'equations, une frequence mensuelle, un detail sectoriel assez fin et la publication d'intervalles de confiance relatifs a la prevision.Modèles economiques ; Prevision ; Instrument de mesure ; Prix

Optimized diffusion gradient orientation schemes for corrupted clinical DTI data sets

Object:A method is proposed for generating schemes of diffusion gradient orientations which allow the diffusion tensor to be reconstructed from partial data sets in clinical DT-MRI, should the acquisition be corrupted or terminated before completion because of patient motion. Materials and methods: A general energy-minimization electrostatic model was developed in which the interactions between orientations are weighted according to their temporal order during acquisition. In this report, two corruption scenarios were specifically considered for generating relatively uniform schemes of 18 and 60 orientations, with useful subsets of 6 and 15 orientations. The sets and subsets were compared to conventional sets through their energy, condition number and rotational invariance. Schemes of 18 orientations were tested on a volunteer. Results: The optimized sets were similar to uniform sets in terms of energy, condition number and rotational invariance, whether the complete set or only a subset was considered. Diffusion maps obtained in vivo were close to those for uniform sets whatever the acquisition time was. This was not the case with conventional schemes, whose subset uniformity was insufficient. Conclusion: With the proposed approach, sets of orientations responding to several corruption scenarios can be generated, which is potentially useful for imaging uncooperative patients or infant

Duality and ontology

A ‘duality’ is a formal mapping between the spaces of solutions of two empirically equivalent theories. In recent times, dualities have been found to be pervasive in string theory and quantum field theory. Naïvely interpreted, duality-related theories appear to make very different ontological claims about the world—differing in e.g. space-time structure, fundamental ontology, and mereological structure. In light of this, duality-related theories raise questions familiar from discussions of underdetermination in the philosophy of science: in the presence of dual theories, what is one to say about the ontology of the world? In this paper, we undertake a comprehensive and non-technical survey of the landscape of possible ontological interpretations of duality-related theories. We provide a significantly enriched and clarified taxonomy of options—several of which are novel to the literature

Monitoring of ultrafine particles in French regional air quality network

Monitoring of ultrafine particles (UFP) in the ambient air is ongoing since 2012 in France. A national working group was created in 2014, including nowadays five French regional air quality monitoring networks. The main instrument selected to monitor UFP is the particle sizer “UFP-3031” (TSI Inc.). It measures the particle number concentration between 20 and 800 nm with six size channels. Two intercomparisons were organized in 2014 and 2015, which evaluated the accuracy of this instrument through a comparison with other techniques (such as Scanning Mobility Particle Sizer, SMPS), and through uncertainty calculations. Recently, several networks have been also equipped with CPC (condensation particle counter) to be able to measure the total UFP number concentration from 7 nm. This work presents the main results of short and long-term measurement of UFP which have been carried out in various environments: urban/traffic sites, near heavy industry zones (Dunkerque and Fos-sur-Mer in northern and southern France, respectively), near harbor area (Nice)… For urban/ traffic environment, the number concentration and size distribution are compared at the national level; it appears that they vary significantly depending on the influence of road traffic around the site. The concentration levels near traffic sites are at least twice than in the urban area, especially for UFP smaller than 50 nm. Additionally, the UFP measurement also makes it possible to improve the identification of specific sources and to understand the atmospheric physicochemical phenomena. The relationship between UFP and industrial emissions, ferries, forest fires was clearly identified in different places in France. During summer, the UFP monitoring also shows the formation of new particles (between 20-30 nm or smaller) in the afternoon, due to photochemical reactions. From 2019, the French national strategy on UFP will start putting a particular emphasis on the impact of UFP on human health

Analytic Metaphysics versus Naturalized Metaphysics: The Relevance of Applied Ontology

The relevance of analytic metaphysics has come under criticism: Ladyman & Ross, for instance, have suggested do discontinue the field. French & McKenzie have argued in defense of analytic metaphysics that it develops tools that could turn out to be useful for philosophy of physics. In this article, we show first that this heuristic defense of metaphysics can be extended to the scientific field of applied ontology, which uses constructs from analytic metaphysics. Second, we elaborate on a parallel by French & McKenzie between mathematics and metaphysics to show that the whole field of analytic metaphysics, being useful not only for philosophy but also for science, should continue to exist as a largely autonomous field

Mortar FEs on Overlapping Meshes : Application to Magnetodynamics

Abstract The finite element (FE) method is frequently used in magnetodynamics as well suited to treat problems with complex geometries while keeping a simplicity in the implementation. However, some modelisations, as in eddy current (EC) non destructive testing (NDT), present the particularity to have moving parts. A global remeshing can be necessary which causes expensive CPU time. Domain decomposition methods allowing to take into account the movement without having to remesh the whole computational domain. The mortar element method (MEM), a variational non-conforming domain decomposition approach [1] offers attractive advantages in terms of flexibility and accuracy. In its original version for non-overlapping subdomains, the information is transferred through the skeleton of the decomposition by means of a suitable L 2 -projection of the field trace from the master to the slave subdomains. A MEM with overlapping subdomains has been proposed to coupled a global scalar potential defined everywhere in the considered domain and a local vector potential defined only in (possibly moving) conductor

Price Setting in the Euro Area: Some Stylized Facts from Individual Consumer Price Data.

This paper documents patterns of price setting at the retail level in the euro area. A set of stylized facts on the frequency and size of price changes is presented along with an econometric investigation of their main determinants. Price adjustment in the euro area can be summarized in six stylized facts. First, prices of most products change rarely. The average monthly frequency of price adjustment is 15 p.c., compared to about 25 p.c. in the US. Second, the frequency of price changes is characterized by substantial cross-product heterogeneity and pronounced sectoral patterns: prices of (oil-related) energy and unprocessed food products change very often, while price adjustments are less frequent for processed food products, non-energy industrial goods and services. Third, cross-country heterogeneity exists but is less pronounced. Fourth, price decreases are not uncommon. Fifth, price increases and decreases are sizeable compared to aggregate and sectoral inflation rates. Sixth, price changes are not highly synchronized across price-setters. Moreover, the frequency of price changes in the euro area is related to a number of factors, in particular seasonality, outlet type, indirect taxation, use of attractive prices as well as aggregate or product-specific inflation.Price-setting ; consumer price ; frequency of price change.