Abstract: The process, the imaging system and the probe are intended to obtain images by way of waves emitted by an antenna after reflection of these waves at the level of a target-like assembly illuminated by the waves emitted and on the basis of which the images are extracted, said antenna consisting of at least one array of wave emitter/receiver tranducers. The process carries out a series of emissions of the same type by providing the transducers with identical excitation signals which are staggered in time so as to generate an essentially plane wave at each emission. The delays between transducers is determined so that the equiphase surfaces obtained are in line or in a plane according to whether the antenna includes an array of transducers.

Abstract: Echography system consisting of an echograph (4) with which is associated an acoustic probe (1) comprising at least one antenna composed of a plurality of acoustic transducers making it possible to sound-sweep a working volume in which the tissues to be examined are to be situated, or placed.

Abstract: The process, the imaging system and the probe are intended to make it possible to obtain images by way of waves emitted by an antenna (1), after reflection of these waves at the level of a target-like assembly illuminated by the waves emitted and on the basis of which the images are extracted, said antenna consisting of at least one alignment of wave emitter/receiver transducers.

Abstract: The invention concerns a method for making an organo-soluble (meth)acrylic resin composition which consists in: esterifying the COOH functions of a polymer comprising units derived from methacrylic acid, in a solvent medium, with Ti(OR)4, R representing one among ethyl, isopropyl, n-butyl, t-butyl, 2-ethylhexyl and t-amyl. The invention is characterised in that the esterification is carried out in the presence of at least a R′COOH monocarboxylic acid, R′ representing a linear, branched or cyclic C1-C18 alkyl radical; aryl; alkaryl; or aralkyl, by stopping esterification before a gel is formed, when the COOH resin and R′COOH functions have been added with a molar ratio Ti(OR)4/—COOH functions of the resin ranges between 1 and 3, and a molar ratio R′COOH/Ti(OR)4 ranges between 1 and 6.

Abstract: These compounds are denoted by the formula (I): ##STR1## in which R denotes a tert-butyl, tert-amyl or 2-ethylhexyl radical. To prepare them, methacrylic acid is reacted with a tetraalkoxytitanium Ti(OR).sub.4, where R=isopropyl or tert-butyl, to obtain a corresponding compound (I), or with Ti(OR) (OtAm).sub.3, where R=isopropyl or tert-butyl and tAm=tert-amyl, to obtain a compound (I) with R=tert-amyl, the compounds (I) with R=isopropyl or tert-butyl furthermore denoting intermediate synthesis products which can be reacted with tert-amyl alcohol or with 2-ethylhexanol, to obtain a compound (I) in which R denotes tert-amyl or 2-ethylhexyl respectively.

Abstract: This organosoluble (meth)acrylic resin composition is characterized in that it includes a polymer containing units derived from methacrylic acid which are esterified with --Ti(OR).sub.3 groups, mixed with free Ti(OR).sub.4, which represents the excess of Ti(OR).sub.4 which has been introduced for the preparation of the said polymer in sufficient quantity for the resulting composition to be organosoluble and not in gel form, R representing one of ethyl, isopropyl, n-butyl, t-butyl, 2-ethylhexyl and t-amyl. It may be the product of esterification in a solvent medium of a polymer containing units derived from methacrylic acid with Ti(OR).sub.4, the Ti/COOH molar ratio being higher than 1, preferably being between 3/1 and 10/1; or the product of radical copolymerization in a solvent medium of at least one methacrylic acid esterified with Ti(OR).sub.3 and of at least one comonomer, in the presence of Ti(OR).sub.4, in a quantity which would have corresponded to a reaction between the methacrylic acid and Ti(OR).

Abstract: Formation of channels for all-round passive sonar systems by the technique of charge-coupled devices. The shift register receives the multiplexed signals of the M transducers forming the listening base of the sonar system. The shift register has different series of sub-contacts, each series corresponding, at one moment, to the signal of one of the transducers. The adding of the weighted signals of one series gives an interpolated signal of the corresponding transducer. The such obtained delayed signals are weighted and added, such obtaining the preformed channels.