Abstract: A data set comprises data obtained by seismic imaging of a region of interest during an observation period. An intrinsic geological variability of a region is determined from the comparison of reception signals for neighbor bins as a function of a difference in signal geometry for the neighbor bins.

Abstract: A method of determining the position of a detector disposed under the sea, comprising the following steps: emit N waves from N emission points, record the propagation time of said wave between each emission point and the detector; determine the P time intervals Ti, with P?1 such that, for each time interval Ti, there exist Mi emission points, Mi?3 for 1?i?P, whose propagation times lie in the time interval, determine for each time interval Ti of the circle which passes closest to the Mi points whose propagation time lies in said time interval, and then determine the position of the detector as being the barycenter of the P centers of the circles determined previously.

Abstract: A data set comprises data obtained by seismic imaging of a region of interest during an observation period. An intrinsic geological variability of a region is determined from the comparison of reception signals for neighbour bins as a function of a difference in signal geometry for the neighbour bins.

Abstract: A method for delineating a data stream transmitted by a communication system using a protocol stack includes: analyzing the redundancy of sequences, the content of which is set on one or more layers in a protocol stack to delineate packets, errored or not, in a continuous data stream; the method to this end including searching in the receiver for sequences corresponding to a known sequence SP present in the received stream, and doing so by detecting sequences similar to this known sequence, the non-similar sequences not being retained; the method further including, in the presence of similar sequences, storing their position to determine the start of the packets.

Abstract: The subject of the present invention is a method for correcting transmission errors in a data stream transmitted by a communications system using a protocol stack. According to the invention, the method consists in utilizing the redundancy of sequences whose content is fixed across several layers in a stack of protocols so as to correct transmission errors; the method consisting to this end in searching at the level of the receiver for sequences corresponding to a known sequence present in the stream received and doing so by detecting sequences similar to this known sequence, non-similar sequences not being retained; the method consisting furthermore, when similar sequences are present, in detecting transmission errors in the known sequence and in modifying the similar sequences (erroneous sequences) with the aid of the known sequence.

Abstract: The invention relates to a method for determining, for a detector placed on the surface of the seabed, the vertical propagation time and the velocity of propagation in the water of a wave emitted from an emission point. The method includes: emitting a wave from the emission point; recording the wave received by the detector; determining the vertical propagation time by, where tdir is the direct wave propagation time between the emission point and the detector, and tmul is the propagation time of the first multiple wave between the emission point and the detector; and determining the velocity of propagation of the wave, where X is the distance between the emission point and the water-surface point that is vertical to the detector.

Abstract: A method of determining the relative position of two detectors at the bottom of the sea by emitting N waves from a first set of N emission points, and recording for each point of emission of the first set the propagation time of the wave between said emission point and a first detector R1. Next, emitting Q waves from a second set of Q emission points, and recording for each emission point of the second set the propagation time of the wave between the emission point and a second detector R2. Relative position of the two detectors R1 and R2 can then be determined.

Abstract: A method of determining the position of a detector disposed under the sea, comprising the following steps: emit N waves from N emission points, record the propagation time of said wave between each emission point and the detector; determine the P time intervals Ti, with P?1 such that, for each time interval Ti, there exist Mi emission points, Mi?3 for 1?i?P, whose propagation times lie in the time interval, determine for each time interval Ti of the circle which passes closest to the Mi points whose propagation time lies in said time interval, and then determine the position of the detector as being the barycenter of the P centers of the circles determined previously.

Abstract: A method for delineating a data stream transmitted by a communication system using a protocol stack includes: analyzing the redundancy of sequences, the content of which is set on one or more layers in a protocol stack to delineate packets, errored or not, in a continuous data stream; the method to this end including searching in the receiver for sequences corresponding to a known sequence SP present in the received stream, and doing so by detecting sequences similar to this known sequence, the non-similar sequences not being retained; the method further including, in the presence of similar sequences, storing their position to determine the start of the packets.

Abstract: The subject of the present invention is a method for correcting transmission errors in a data stream transmitted by a communications system using a protocol stack. According to the invention, the method consists in utilizing the redundancy of sequences whose content is fixed across several layers in a stack of protocols so as to correct transmission errors; the method consisting to this end in searching at the level of the receiver for sequences corresponding to a known sequence present in the stream received and doing so by detecting sequences similar to this known sequence, non-similar sequences not being retained; the method consisting furthermore, when similar sequences are present, in detecting transmission errors in the known sequence and in modifying the similar sequences (erroneous sequences) with the aid of the known sequence.