167 research outputs found

    An Inflation Forecasting Model for the Euro Area.

    Get PDF
    With the European economic integration, the understanding of inflation and inflationary pressures requires to analyse both the national level and the whole Euro area level. This is true in particular for the inflation forecasts that are carried out within the Eurosystem and published four times a year in the ECB Monthly Bulletin. For that purpose, the Banque de France is currently building tools for the Euro area in addition to those already in use for France. The present study puts forward a simple model of short-term developments (one year ahead) in inflation, as measured by the Harmonized Index of Consumer Prices (HICP) of the Euro area. This model does not take into account the feed-back effect of prices on activity, which should be considered in order to analyse medium-term price developments. It could hence be improved along these lines in the future. The model includes seven equations, explaining the total HICP of the Euro area and some of its sector-based sub-indexes (services, manufacturing sector, unprocessed food, processed food, energy and underlying inflation, defined as HICP inflation excluding unprocessed food and energy prices). It uses exogenous variables such as unit labour cost, import deflator, indicators of tightening in the labour market, or in the goods market, and indirect tax indicators. We have favoured an empirical approach rather than a strict compliance with theoretical models, paying particularly attention to the fit of the equations to the data. However, this model is able to provide relevant economic interpretations of recent price developments. Finally, we assess the forecasting performance of the model in traditional in-sample and out-of-sample rolling event evaluations. To do so, the forecasts were compared to the ones obtained from simple autoregressive equations, which are also commonly used to forecast short-term price developments. On the whole, the model provides more accurate forecasts than those provided by the autoregressive model, and a sector-based disaggregated approach outperforms a single equation to forecast total HICP. Part of this result may come from dummy variables that correspond to well identified shocks that improve both the econometric characteristics and forecast performance of the equations of our model.Inflation ; Economic Modelling ; Forecast.

    Gravitational Wave - Gauge Field Oscillations

    Get PDF
    Gravitational waves propagating through a stationary gauge field transform into gauge field waves and back again. When multiple families of flavor-space locked gauge fields are present, the gravitational and gauge field waves exhibit novel dynamics. At high frequencies, the system behaves like coupled oscillators in which the gravitational wave is the central pacemaker. Due to energy conservation and exchange among the oscillators, the wave amplitudes lie on a multidimensional sphere, reminiscent of neutrino flavor oscillations. This phenomenon has implications for cosmological scenarios based on flavor-space locked gauge fields.Comment: 4 pages, 3 figures, 1 animation; replacement matches published versio

    Maquette d’inflation zone euro.

    Get PDF
    Selon la maquette d’inflation pour la zone euro dĂ©veloppĂ©e Ă  la Banque de France, la reprise de l’inflation sous-jacente en 2007 est la consĂ©quence de tensions cycliques et de la vive progression passĂ©e des prix d’importations.Inflation, modĂ©lisation Ă©conomique, prĂ©vision.

    Variantes en Univers Incertain.

    Get PDF
    In this paper, we try to illustrate the interest of the Bayesian approach for the evaluation of economic policies, often realised by analysing the response of the economy to a standard shock. We present a Stochastic Dynamic General Equilibrium model for the euro area. The Bayesian estimation gives a measure of the uncertainty on the parameters, from which we can derive the uncertainty of the responses to standard shocks. As an illustration, we simulate the effects of a fiscal shock (announced VAT increase).DSGE, Euro zone, Nominal rigidities, Bayesian estimation.

    Te-based chalcogenide materials for selector applications

    Get PDF
    The implementation of dense, one-selector one-resistor (1S1R), resistive switching memory arrays, can be achieved with an appropriate selector for correct information storage and retrieval. Ovonic threshold switches (OTS) based on chalcogenide materials are a strong candidate, but their low thermal stability is one of the key factors that prevents rapid adoption by emerging resistive switching memory technologies. A previously developed map for phase change materials is expanded and improved for OTS materials. Selected materials from different areas of the map, belonging to binary Ge-Te and Si-Te systems, are explored. Several routes, including Si doping and reduction of Te amount, are used to increase the crystallization temperature. Selector devices, with areas as small as 55 x 55 nm(2), were electrically assessed. Sub-threshold conduction models, based on Poole-Frenkel conduction mechanism, are applied to fresh samples in order to extract as-processed material parameters, such as trap height and density of defects, tailoring of which could be an important element for designing a suitable OTS material. Finally, a glass transition temperature estimation model is applied to Te-based materials in order to predict materials that might have the required thermal stability. A lower average number of p-electrons is correlated with a good thermal stability

    The maximum of the local time of a diffusion process in a drifted Brownian potential

    Full text link
    We consider a one-dimensional diffusion process XX in a (−Îș/2)(-\kappa/2)-drifted Brownian potential for Îș≠0\kappa\neq 0. We are interested in the maximum of its local time, and study its almost sure asymptotic behaviour, which is proved to be different from the behaviour of the maximum local time of the transient random walk in random environment. We also obtain the convergence in law of the maximum local time of XX under the annealed law after suitable renormalization when Îș≄1\kappa \geq 1. Moreover, we characterize all the upper and lower classes for the hitting times of XX, in the sense of Paul L\'evy, and provide laws of the iterated logarithm for the diffusion XX itself. To this aim, we use annealed technics.Comment: 38 pages, new version, merged with hal-00013040 (arXiv:math/0511053), with some additional result

    Electronic defect study on low temperature processed Cu(In,Ga)Se2 thin-film solar cells and the influence of an Sb layer

    Get PDF
    A way to lower the manufacturing cost of Cu(In,Ga)Se-2 (CIGS) thin-film solar cells is to use flexible polymer substrates instead of rigid glass. Because such substrates require lower temperature during absorber deposition, the grain growth of the absorber layer can be hindered which leads to a lower cell performance. Partial compensation of this efficiency loss might be accomplished by growing the absorber in the presence of Sb, which is reported to promote grain growth. In this work CIGS solar cells, deposited on glass substrates, at a reduced substrate temperature with a thin Sb layer (7, 12 nm) on top of the Mo contact are investigated. The diffusion profile of Sb is measured with plasma profiling time of flight mass spectrometry. The beneficial effect of Sb on efficiency and grain size is shown in quantum efficiency measurements and with scanning electron microscopy, respectively. Electric spectroscopy is used to explore the possible effects on the defect structure, more in particular on the dominant shallow acceptor. Admittance spectra exhibit a capacitance step to the geometric capacitance plateau at low temperature (5-60 K). Analyzing this capacitance step, we obtained a good estimate of the activation energy of the intrinsic defects that provide the p-type conductivity of the CIGS absorber. The measurements did not show a change in the nature of the dominant acceptor upon Sb treatment

    Prospecting environmental mycobacteria: combined molecular approaches reveal unprecedented diversity

    Get PDF
    Background: Environmental mycobacteria (EM) include species commonly found in various terrestrial and aquatic environments, encompassing animal and human pathogens in addition to saprophytes. Approximately 150 EM species can be separated into fast and slow growers based on sequence and copy number differences of their 16S rRNA genes. Cultivation methods are not appropriate for diversity studies; few studies have investigated EM diversity in soil despite their importance as potential reservoirs of pathogens and their hypothesized role in masking or blocking M. bovis BCG vaccine. Methods: We report here the development, optimization and validation of molecular assays targeting the 16S rRNA gene to assess diversity and prevalence of fast and slow growing EM in representative soils from semi tropical and temperate areas. New primer sets were designed also to target uniquely slow growing mycobacteria and used with PCR-DGGE, tag-encoded Titanium amplicon pyrosequencing and quantitative PCR. Results: PCR-DGGE and pyrosequencing provided a consensus of EM diversity; for example, a high abundance of pyrosequencing reads and DGGE bands corresponded to M. moriokaense, M. colombiense and M. riyadhense. As expected pyrosequencing provided more comprehensive information; additional prevalent species included M. chlorophenolicum, M. neglectum, M. gordonae, M. aemonae. Prevalence of the total Mycobacterium genus in the soil samples ranged from 2.3×107 to 2.7×108 gene targets g−1; slow growers prevalence from 2.9×105 to 1.2×107 cells g−1. Conclusions: This combined molecular approach enabled an unprecedented qualitative and quantitative assessment of EM across soil samples. Good concordance was found between methods and the bioinformatics analysis was validated by random resampling. Sequences from most pathogenic groups associated with slow growth were identified in extenso in all soils tested with a specific assay, allowing to unmask them from the Mycobacterium whole genus, in which, as minority members, they would have remained undetected
    • 

    corecore