Abstract: The present invention relates to a sound system (10) for a pool with at least a first wall (101A) and a second wall (102A), one of which is intended to be at least partially submerged in the pool (1) and the other to be above water, a first and a second electroacoustic transducer (111, 112) attached to the first and second walls (101A, 102A) respectively, and a control unit (130) configured to control and power the first and second electroacoustic transducers (111, 112). The control unit (130) with a radio-frequency communication module (131), such as a Bluetooth™ or wifi™ communication module, including at least one antenna (131A) arranged in the sound system in such a way that the antenna is at least partly above a waterline (3) of the pool.

Abstract: The invention is for a communicating diving mask with a body including a frame (20) surrounding at least part of a user's face; a glass (10) surrounded by the frame (20), where the diving mask has an electromagnetic transducer (23) arranged in contact with the glass to vibrate it; and a microphone (22) arranged in the mask, and a control unit (25) configured to control the vibration of the electromagnetic transducer (23) on the basis of a signal transmitted by the microphone (22).

Abstract: The invention concerns a bedsore prevention device (20) designed to be equipped to a support element of a piece of receiving furniture. The prevention device (20) has a bearing surface (22), intended to be flush with a surface of the support element and to be in direct or indirect contact with a body part of the subject on which the subject is likely to develop bedsores, at least three electromechanical transducers arranged to urge the bearing surface (22) to move, the at least three transducers being arranged along the bearing surface (22), a control unit (26) for the at least three transducers, the control unit (26) being configured to control the at least three transducers to urge the bearing surface in a phase-shifted manner in order to simulate a mechanical traveling wave along the bearing surface.

Abstract: An afterbody for a turbojet engine having a central axis, provided with a nozzle comprising two doors facing each other between two lateral beams. The doors pivot around axes defining a pivot direction, between a retracted position, in which a middle portion of the downstream edge of the doors forms the edge of the outlet section of the nozzle combined with the downstream edges of the two lateral beams, and a deployed position, in which the middle portions of the downstream edges of the pivoting doors come together so as to block the channel between the two lateral beams in order to reverse the thrust of the turbojet engine gases. The edge of the outlet section of the nozzle further having a crown of noise-reducing chevrons alternating with indentations and the afterbody.

Abstract: A propulsion device including an unducted upstream propeller and a counter-rotating and coaxial downstream propeller. At least one blade of the upstream propeller is configured to generate a corotating secondary vortex for acting upstream of the downstream propeller to destabilize a blade tip vortex of the same at least one blade.

Abstract: A blade, configured to be mounted on a hub of a turbomachine propeller so that an empty space is defined between a base of the blade and a face of the hub facing the base. The blade includes a retractable blanking mechanism configured to reversibly occupy at least one of following two positions: a deployed position in which the retractable blanking mechanism at least partially closes off the empty space; and an extreme retracted position in which the retractable mechanism is kept out of the empty space.

Abstract: An afterbody for a turbojet engine having a central axis, provided with a nozzle comprising two doors mounted facing each other between two lateral beams pivoting around axes defining a pivot direction, between a retracted position, in which a middle portion of the downstream edge of said doors forms the edge of the outlet section of the nozzle combined with the downstream edges of the two lateral beams, and a deployed position, in which said middle portions of the downstream edges of the pivoting doors come together so as to block the channel between the two lateral beams in order to reverse the thrust of the turbojet engine gases, the edge of the outlet section of the nozzle further having a crown of noise-reducing chevrons alternating with indentations and the afterbody wherein each noise-reducing chevron formed on the middle portion of the downstream edge of a pivoting door is opposite an indentation in the middle portion of the other pivoting door in the direction perpendicular to said pivot direction, t

Abstract: A door for a door-type thrust reverser is able to move between a direct jet mode of a nacelle and a reverse jet mode. The door includes an inner wall being integrated into a flow path of an air flow generated by a turbojet engine, an outer wall, at least one side wall connecting the inner wall to the outer wall of the door, and a deflector to deflect the air flow. In particular, the deflector includes a cavity of the door which is shaped to convey a fraction of the air flow from one air inlet rigidly secured to the inner wall of the door to one air outlet rigidly secured to the side wall of the door, so as to redirect, during operation of the nacelle in the reverse jet mode, a part of the air flow upstream from the inner wall of the door.

Abstract: A propulsion device including an unducted upstream propeller and a counter-rotating and coaxial downstream propeller. At least one blade of the upstream propeller is configured to generate a corotating secondary vortex for acting upstream of the downstream propeller to destabilize a blade tip vortex of the same at least one blade.

Abstract: A blade, configured to be mounted on a hub of a turbomachine propeller so that an empty space is defined between a base of the blade and a face of the hub facing the base. The blade includes a retractable blanking mechanism configured to reversibly occupy at least one of following two positions: a deployed position in which the retractable blanking mechanism at least partially closes off the empty space; and an extreme retracted position in which the retractable mechanism is kept out of the empty space.