From Jean-Philippe.Lagrange at ign.fr Tue Feb 26 09:39:35 2008 From: Jean-Philippe.Lagrange at ign.fr (Jean-Philippe Lagrange) Date: Tue, 26 Feb 2008 18:39:35 +0100 Subject: [IGSMAIL-5724]: Research position available in geodesy Message-ID: <5B9959D8CE0AB74888C1E9D5939F825B01570A68@haiaiel.ign.fr> ****************************************************************************** IGS Electronic Mail 26 Feb 09:48:34 PST 2008 Message Number 5724 ****************************************************************************** Author: Jean-Philippe Lagrange Please find hereafter a position opened at the French National Geographic Institute geodetic research laboratory. With best regards, Jean-Philippe Lagrange Deputy Technical Director Research position available in geodesy Background The Laboratoire de Recherche en Geodesy (LAREG) has the responsibility at the international level of the definition, execution and long-term maintenance of the International Terrestrial Reference System (ITRS). This responsibility is part of the contribution of the National Geographical Institute to the International Earth Rotation and Reference Systems Service (IERS). Instantiation of the ITRS, called ITRF (International Terrestrial Reference Frame, see http://itrf.ensg.ign.fr). Long term stability of ITRF at a millimeter accuracy level is a prerequisite for the observation of slow geophysical phenomena, which relies on comparing geodetic positions for years or even decades away. In this context, the laboratory has carried out several projects based on analyzing and accumulating time series of positions as well as Earth orientation parameters. The analysis of these time series reveals seasonal variations that may reflect both systematic errors of space geodesy techniques and geophysical phenomena. We are interested in the study of the movement of the gravity center of the Earth and all types of large-scale deformation (earthquakes, atmospheric, oceanic and hydrological overloads), either to improve knowledge of these movements and deformations, and understand artifacts, or to validate space geodesy findings (based on comparing of measurement techniques and geophysical modeling). This research, as well as the recent publication of ITRF2005, has pointed out the need to develop a focused research on the accuracy of the reference system (in particular its origin and its scale) and understand the movement and deformation that can pack his determination. Research position The 'chargi de recherche' works within the 'reference system' team, in close collaboration with other laboratory experts specialized in reference systems, space geodesy, and processing of GNSS and LASER observations. He is expected to cooperate closely partners laboratories specialized in geophysics. His research will revolve around the theory of estimation. He will devise new approaches as for the modeling of non-secular movements, their inclusion in the estimate of the error of determining the gravity center and scale of reference, and will study the contribution of non linear estimation methods (e.g., genetic algorithms). He will address various issues as for modeling the movement and distortion of the Earth, in partnership with other teams in the fields of Geodesy and Geophysics (in France and abroad). He will focus on analyzing and quantifying the causes. His contribution in these areas is primarily geodetic, experts in geophysics will take advantage of his results to confirm or refute theories on the origin and nature of the movements. This research activity entails the use of a range of scientific software packages designed for processing geodetic data. Research may include developing additions to these software packages. Taking part in international working groups is also to be considered a plain part of this position. Knowledge and Skills 1 / The successful candidate will have a good knowledge of estimation theory, at least in the field of linear estimation (least squares, inverse problems, estimator accuracy...). 2 / He will have a working knowledge of Geodesy; a research experience involving space geodesy data processing will be a plus 3 / The successful candidate will master analysis and numerical calculations, and the most common geodetic software packages. Applications Applications are online and must be submitted before April 4, 2008: http://www2.equipement.gouv.fr/recrutement/index_inscriptions.htm after submitting your file, you will be invited to take part in a competitive exam. Oral exam sessions will be held after June 9, 2008.