ALBERT

Description: This thesis is devoted to an in-depth analysis of the ability of "Artificial Neural Networks" (ANN) to achieve reliable ground motion predictions. A first important aspect concerns the derivation of "GMPE" (Ground Motion Prediction Equations) with an ANN approach, and the comparison of their performance with those of "classical" GMGEs derived on the basis of empirical regressions with pre-established, more or less complex, functional forms. To perform such a comparison involving the two "betweeen-event" and "within-event" components of the random variability, we adapt the algorithm of the "random effects model" to the neural approach. This approach is tested on various, real and synthetic, datasets: the database compiled from European, Mediterranean and Middle Eastern events (RESORCE: Reference database for Seismic grOund-motion pRediction in Europe), the database NGA West 2 (Next Generation Attenuation West 2 developed in the USA), and the Japanese database derived from the KiK-net accelerometer network. In addition, a comprehensive set of synthetic data is also derived with a stochastic simulation approach. The considered ground motion parameters are those which are most used in earthquake engineering (PGA, PGV, response spectra and also, in some cases, local amplification functions). Such completely "data-driven" neural models, inform us about the respective, and possibly coupled, influences of the amplitude decay with distance, the magnitude scaling effects, and the site conditions, with a particular focus on the detection of non-linearities in site response. Another important aspect is the use of ANNs to test the relevance of different site proxies, through their ability to reduce the random variability of ground motion predictions. The ANN approach allows to use such site proxies either individually or combined, and to investigate their respective impact on the various characteristics of ground motion. The same section also includes an investigation on the links between the non-linear aspects of the site response and the different site proxies. Finally, the third section focuses on a few source-related effects: analysis of the influence of the "style of faulting" on ground motion, and, indirectly, the dependence between magnitude and seismic stress drop

Description: The IUGG Yearbook is a reference document of IUGG members, administrative officers, and Association and Union Commission officers that is updated annually and distributed free of charge. Each issue endeavors to update the contact information for hundreds of persons who are actively participating in IUGG scientific activities. Information is complied throughout the year until end December. The Yearbooks are published and posted at the IUGG webpage at the beginning of the year. The Yearbooks are printed together with the Annual Reports for the preceding year in May and mailed to National Committee for Geodesy and Geophysics, Adhering Bodies, IUGG partners, and major libraries.

Description: Comme premier résultat de son travail, le groupe ad hoc Open-Access-Gold présente cette prise de position. Il s’adresse à des institutions scientifiques qui sont impliquées dans divers aspects de la publication Open Access. Il structure et évalue les exigences dans les contrats basés sur le modèle auteur-payeur. De plus, il évoque les liens entre abonnement et Libre accès et émet des suggestions aux institutions concernées pour la mise en oeuvre de leurs stratégies en matière de Libre accès. L’objectif est d’établir, dans le domaine de la publication scientifique, de la transparence et de la pérennité selon les principes de la Science, et d’éviter la répétition de certaines dérives observées dans le passé.