Abstract: An underwater acoustic deception system deceives a sensor installed on a threat existing in or on water by acoustic effect in order to protect ships from the threat. The underwater acoustic deception system is provided with a control device, a laser oscillator and emission optical system. The control device determines a focusing position to focus a laser beam (50) in water in order to generate bubbles (70) at a desired position with a desired scale and emission parameters of the laser beam (50). The laser oscillator generates the laser beam (50) configured to focus in water and generate bubbles. The emission optical system emits the generated laser beam (50) to the focusing position. The underwater acoustic deception system deceives an arbitrary sensor existing in the water by acoustic effect of the bubbles (70) on the surroundings.

Abstract: A sound producing device includes at least one air pulse generating element. Each of the at least one air pulse generating element includes a membrane, a first air chamber and at least one opening, wherein a chamber pressure exists in the first air chamber. The membrane is actuated to change the chamber pressure of the first air chamber to generate a plurality of air pulses, the air pulses are propagated through the at least one opening, the air pulses produce a non-zero offset in terms of sound pressure level, and the non-zero offset is a deviation from a pressure value of an ambient pressure outside the sound producing device.

Abstract: An electronic device whose enclosure or housing panel is used as part of an acoustic system is described. The panel is divided into several sub-panels. For each sub-panel, the device includes one or more actuators attached to vibrate the sub-panel. The actuator and its attached sub-panel convert an audio signal to acoustic output. Each actuator and sub-panel combination may receive a separate audio signal. The device includes a digital signal processor for controlling each of the sub-panel driving audio signals. The device may further include one or more backing frames that are attached to the panel to provide boundary conditions to the sub-panels. The boundary conditions define a resonance frequency for each sub-panel.

Abstract: According to an embodiment, a method of operating a speaker with an acoustic pump includes generating a carrier signal having a first frequency by exciting the acoustic pump at the first frequency and generating an acoustic signal having a second frequency by adjusting the carrier signal. In such embodiments, the first frequency is outside an audible frequency range and the second frequency is inside the audible frequency range. Adjusting the carrier signal includes performing adjustments to the carrier signal at the second frequency. Other embodiments include corresponding systems and apparatus, each configured to perform corresponding embodiment methods.

Abstract: A method of calibrating transceiver positions inside an acoustic pyrometry measuring vessel that contains a plurality of transceivers, includes determining (40) a speed of sound in the acoustic pyrometry measuring vessel from a temperature and gas composition of a gas inside the acoustic pyrometry measuring vessel, acquiring (41) time-of-flight (TOFs) ?ti,j measurements from a plurality of pairs i,j of transceivers inside the acoustic pyrometry measuring vessel, estimating (42) a radius of the acoustic pyrometry measuring vessel from an average of the acquired TOF measurements, and using (43) an estimated radius of the acoustic pyrometry measuring vessel to estimate errors ??j of displacement angles of the transceivers.

Abstract: An ultrasonic sensor which includes a substrate where an opening section is formed, a vibration plate that is provided on the substrate so as to close the opening section, and a piezoelectric element that is layered on a surface of the vibration plate on an opposite side to the opening section and includes a first electrode, a piezoelectric element, and a second electrode, includes a reflection layer that is provided in a space around the piezoelectric element on the surface of the vibration plate on an opposite side to the opening section, to reflect other ultrasonic waves which are transmitted in a different direction from a transmitted ultrasonic wave transmitted to a measuring target side on an interface between the piezoelectric element and the reflection layer, and has a thickness so as to superimpose other ultrasonic waves on the transmitted ultrasonic wave.

Abstract: A feedback and feedforward as well as a statistical predictive control system and method for continuously controlling texture of a food snack in a manufacturing process. The feedback system includes a quantitative texture measuring tool that is positioned downstream of a food processing unit. The texture measuring tool continuously measures a texture attribute of food snack from the food processing unit and feeds back texture attribute information to a controller that controls input parameters to food processing unit such that the texture attribute of a resultant food snack falls within an acceptable limit. The texture measuring tool comprises an excitation tool that strikes the food snack and produces an acoustic signal that is processed by a data processing unit. The data processing unit identifies relevant frequencies in the acoustic signal and quantitatively measures a texture attribute based on a correlated model that includes the relevant frequencies.

Abstract: According to an embodiment, a method of operating a speaker with an acoustic pump includes generating a carrier signal having a first frequency by exciting the acoustic pump at the first frequency and generating an acoustic signal having a second frequency by adjusting the carrier signal. In such embodiments, the first frequency is outside an audible frequency range and the second frequency is inside the audible frequency range. Adjusting the carrier signal includes performing adjustments to the carrier signal at the second frequency. Other embodiments include corresponding systems and apparatus, each configured to perform corresponding embodiment methods.

Abstract: A system for storing and releasing hydraulic energy having a controller, a pressure source, a bidirectional valve fluidly connected to the pressure source, an expandable vessel fluidly connected to the bidirectional valve having a plurality of axial folds between first and second ends, and a bidirectional port connected to the pressure source. As the plurality of axial folds expand, a contracted volume of pressure expands increasing stored hydraulic fluid energy in the expandable vessel. As the plurality of axial folds contract, the expanded volume reduces, releasing stored hydraulic fluid energy to nearby subsea equipment on demand as changes in hydraulic fluid energy requirements for the subsea equipment changes. Simultaneously, hydrostatic seawater pressure of seawater on the expandable vessel is counteracted with the hydrostatic pressure of fluid inside the expandable vessel.

Abstract: Marine vibrators and methods of use are disclosed. A marine vibrator may comprise a containment housing, where the containment housing comprises a marine vibrator internal volume, wherein the marine vibrator internal volume comprises a first gas at a first gas pressure. The marine vibrator may further comprise a sound radiating surface. The marine vibrator may additionally comprise a compliance chamber in contact with the first gas, wherein the compliance chamber comprises a chamber housing and a moveable structure, wherein at least the chamber housing and the moveable structure form a compliance chamber internal volume which holds a second gas at a second gas pressure, wherein the moveable structure is configured to move in response to a change in the first gas pressure, and wherein the compliance chamber is configured to condense the second gas in response to compression of the marine vibrator internal volume by the moveable structure.

Abstract: An ultrasonic transducer, and an ultrasonic wave generating apparatus and an ultrasonic system including the same. The ultrasonic transducer includes a light-absorbing layer configured to absorb light incident on the light-absorbing layer and to generate heat based on the absorbed light; and a thermoelastic layer which is disposed on the light-absorbing layer and which is configured to thermally expand based on the heat to generate ultrasonic waves.

Abstract: A projectile launching device includes a reactive driver, a flyer housing, a flyer and a compressible buffer member. When detonated, the reactive driver will generate a detonation shock wave. The flyer housing defines a bore. The flyer is disposed in the bore and has a rear surface. The buffer member is interposed between the reactive driver and the flyer. The buffer member has a front surface in direct contact with the rear surface of the flyer. The buffer member is configured and arranged to: receive the detonation shock wave from the reactive driver; modify the detonation shock wave to generate a modified shock wave; and transmit the modified shock wave directly to the flyer to thereby propel the flyer away from the buffer member.

Abstract: Disclosed are methods, devices, apparatus, assemblies and systems for generating and directing acoustic energy (e.g. sound). According to some embodiments, there may be provided a cyclical acoustic apparatus or generator comprising a cyclical combustions chamber adapted to cyclically generate acoustic energy. There may be provided an acoustic energy collection and guiding assembly adapted to channel sounds energy generated by said cyclical combustion chamber to an aiming and release apparatus, which aiming and release apparatus directs the acoustic energy towards a target zone.

Abstract: An object is to flatten a frequency characteristic. For achieving the object, an acoustic generator according to an embodiment includes a piezoelectric element (exciter) and a film (film-like vibrating body). The piezoelectric element receives input of an electric signal and vibrates. The piezoelectric element is bonded to the film through a bonding material and the film vibrates together with the piezoelectric element with the vibration of the piezoelectric element. Furthermore, the acoustic generator in the embodiment has voids in the bonding material.

Abstract: A liquid treatment system has a housing defining an interior space. The housing has an inlet port for receiving liquid into the interior space of the housing and an outlet port for allowing liquid to exit the interior space of the housing. The outlet port is spaced from the inlet port so that liquid flows through the interior space of the housing from the inlet port to the outlet port. An ultrasonic waveguide assembly is disposed within the interior space of the housing and includes an ultrasonic horn disposed at least in part intermediate the inlet port and the outlet port of the housing. The ultrasonic horn is operable at an ultrasonic frequency to ultrasonically energize liquid flowing within the housing. An ultraviolet light source emits ultraviolet light into the interior space of the housing to treat liquid flowing therein.

Abstract: A device and method for generating or recovering acoustic energy are provided, including a substrate; at least one deformable cavity disposed in the substrate and being delimited by at least one mobile or deformable wall, the at least one deformable cavity extending in a lateral direction in the substrate defined by a first plane parallel to an upper surface of the substrate; at least one opening disposed in an upper portion of the at least one deformable cavity, configured to transmit at least one pulse produced in the at least one deformable cavity to an ambient atmosphere, the at least one pulse being a pressure pulse, a depression pulse, a partial vacuum pulse, or a combination thereof; and at least one actuator configured to generate a force in the first plane that displaces or deforms, or displaces and deforms, the at least one mobile or deformable wall.

Abstract: A marine seismic source comprises a housing having a central axis, an open end, and a closed end opposite the open end. In addition, the source comprises a piston coaxially disposed within the housing. In addition, the source comprises a flywheel disposed within the housing and axially positioned between the closed end and the piston. The flywheel is configured to rotate about a rotational axis. Further, the source comprises a connecting rod moveably coupling the piston to the flywheel. The connecting rod has a first end pivotally coupled to the piston and a second end pivotally coupled to the flywheel. The second end of the connecting rod has a first position at a first distance measured radially from the rotational axis, and a second position at a second distance measured radially from the rotational axis. The first distance is less than the second distance.

Abstract: An air, fuel, and water mixture is injected into a resonance chamber forming micro-packets. The micro-packets are ignited forming micro-explosions in a combustion chamber containing a central resonance chamber creating a standing wave interfering with a standing wave in the resonance chamber generating the micro-packets. The interfering waves are in phase aiding in the disassociation of molecules, including hydrogen and oxygen, in the air, fuel and water mixture. Efficient combustion is achieved with a nearly zero carbon emissions. The heat generated from the combustion may be used to produce work by any conventional device, such as a steam engine or turbine or generate heat for a building.

Abstract: A method of directing an audio signal to an intended user by a remote-control device coupled to an audio/video device is described. The remote-control device sends an instruction to the audio/video device to transmit an audio signal. The remote-control device receives the audio signal and processes the audio signal to generate a directional audio. The directional audio is then routed to an intended user such that the directional audio signal is audible to the intended user, but not to other recipients in the vicinity.

Abstract: An ultrasonic reactor system with an appropriately designed reactor chamber used in conjunction with a compatible ultrasonic Barbell Horn or its derivative that provides a significant efficiency increase and an intensification of sonochemical and sonomechanical processes is disclosed. These enhancements arise from the ability of the reactor chamber to direct all treated liquid media through the highly active ultrasonic cavitation region located near the surface of the horn, as well as from several improvements in the Barbell Horn design that significantly increase its longevity and in its output surface area, thereby increasing the total size of the active cavitation region.

Abstract: A man-portable non-lethal pressure shield provides both a physical as well as pressure shield. The pressure shield addresses the concerns of military, police and human rights organizations and international law as regards effectiveness, efficiency and safety and efficiency. A folded acoustic horn is incorporated into the physical shell of the shield. The horn couples acoustic pulses from a sonic pulse generator to an acoustic aperture to output a pulsed pressure beam that approximates a plane wave to produce a pressure barrier. The operator may specify a desired effect on its human target that is maintained as range-to-target changes or a desired effect at a specified perimeter range. The shields may be networked to facilitate coordinated action among multiple pressure shields as a force multiplier or to provide a more sophisticated pressure barrier.

Abstract: An acoustic projection screen includes a screen base and a carbon nanotube layer. The carbon nanotube layer is attached to the screen base and connected to electrodes.

Abstract: A portable seismic communication device is disclosed and described. The device can include a tube, a striker, and an adjustable base. The tube can have a lower portion to support an internal gas pressure and an upper portion which can include a contact anvil oriented at a top end of the tube. The striker can be disposed in the tube and can be displaceable along a length of the tube by the internal gas pressure. The adjustable base can be oriented between the tube and a mine floor and can be extendable and retractable to position the anvil in contact with a mine roof (ceiling), such that the striker impacts the contact anvil when displaced by the internal gas pressure to produce an impact energy wave and the contact anvil transmits the impact energy wave to the strata above the device.

Abstract: A system supporting the formation and propagation of tunable highly nonlinear pulses using granular chains composed of non-spherical granular systems. Such a system may be used to support the creation of tunable acoustic band gaps in granular crystals formed of particles with different geometries (spherical or not) in which the tunability is achieved by varying the static precompression, type of excitation and/or pulse amplitude in the system.

Abstract: A method is disclosed for increasing a parametric output of a parametric loudspeaker system. The method can include the operation of providing multiple ultrasonic frequency emission zones that output signals in a frequency band. The phase relationships of the ultrasonic frequency emission zones can be correlated and controlled to increase phase coherence between each ultrasonic frequency emission zone to maximize parametric output. Correlating and controlling the phase relationships can include offsetting a frequency of a carrier signal applied to each emission zone from a resonant frequency of each emission zone in view of a rate of change of phase of each emission zone in a vicinity of each resonant frequency. Ultrasonic energy from the ultrasonic frequency emission zones can be generated, using the correlated phase relationship to increase the parametric output.

Abstract: A sound wave generator that exhibits more excellent output properties than conventional ones, based on the combination of a base layer and a heat-insulating layer that cannot be expected from conventional techniques is provided. The sound wave generator includes a base layer; a heat-insulating layer disposed on the base layer; and a heat pulse source that applies heat pulses to the heat-insulating layer. The base layer is composed of graphite or sapphire, and the heat-insulating layer is composed of crystalline fine particles containing silicon or germanium. The heat pulse source, for example, is a heat pulse-generating layer that is disposed on the surface of the heat-insulating layer opposite to the base layer and applies heat pulses to the heat-insulating layer.

Abstract: A pressure wave generator (1) includes a thermally conductive substrate (2), a heat insulating layer (3) formed on one main surface of the substrate (2), an insulator layer (5) formed on the heat insulating layer (3), and a heat generator (4) formed on the insulator layer (5) to generate heat when a current containing an alternating component is applied thereto. The heat insulating layer (3) is formed containing at least one of silicon nitride (Si3N4), silicon dioxide (SiO2), aluminum oxide (Al2O3), magnesium oxide (MgO), diamond crystalline carbon (C), aluminum nitride (AlN), and silicon carbide (SiC). The heat generator (4) is formed containing, for example, gold (Au) or tungsten (W).

Abstract: The invention relates to a device for generating or recovering acoustic energy, including: at least one first deformable cavity (20) for receiving an ambient atmosphere, made in a first substrate, delimited by at least one wall including at least one mobile or deformable wall (25), and a means for making the cavity communicate with an ambient atmosphere, a means (24, 24?, 241, 24?1) for actuating a displacement or deformation, in the plane of the sensor, or to recover energy resulting from a displacement or deformation, in the plane of the sensor, of said mobile or deformable wall.

Abstract: Methods and systems for Airy waves and Airy wavepackets or Airy beam generation from an input beam or pulse. Airy wavefronts and Airy wavepackets can be generated using Airy beam generation through Fourier synthesis using phase masks or filters in the spatial domain; Airy beam generation using amplitude and phase filters in the spatial domain; and Airy pulse generation through Fourier synthesis using phase and/or amplitude filters in the temporal frequency domain. The Airy waves are highly asymmetric and as a result their energy is more tightly confined in one quadrant thus increasing the energy density in the main lobes. These wavepackets can be one, two, and three-dimensional waves. In addition they tend to self-heal themselves which is important in adverse environments.

Abstract: A thermoacoustic device includes an electrode layer and a sound wave generator. The sound wave generator is disposed on a surface of the sound wave generator. The electrode layer includes a plurality of insulated wires and a plurality of conductive wires. The conductive wires are disposed apart from each other and crossed with the insulated wires. The sound wave generator is electrically connected with conductive wires.

Abstract: Method for producing a stationary wave field of arbitrary shape comprising the steps of defining at least one volume being limited in the direction of the axis of propagation of a beam, of the type 0?z?L; defining an intensity pattern within the said region 0?z?L by a function F(z), describing the said localized and stationary intensity pattern, which is approximated by means of a Fourier expansion or by a similar expansion in terms of (trigonometric) orthogonal functions; providing a generic superposition of Bessel or other beams highly transversally confined; calculating the maximum number of superimposed Bessel beams the amplitudes, the phase velocities and the relative phases of each Bessel beam of the superposition, and the transverse and longitudinal wavenumbers of each Bessel beam of the superposition.

Abstract: A sound wave generator that exhibits more excellent output properties than conventional ones, based on the combination of a base layer and a heat-insulating layer that cannot be expected from conventional techniques is provided. The sound wave generator includes a base layer; a heat-insulating layer disposed on the base layer; and a heat pulse source that applies heat pulses to the heat-insulating layer. The base layer is composed of graphite or sapphire, and the heat-insulating layer is composed of crystalline fine particles containing silicon or germanium. The heat pulse source, for example, is a heat pulse-generating layer that is disposed on the surface of the heat-insulating layer opposite to the base layer and applies heat pulses to the heat-insulating layer.

Abstract: A method, system and device for reproducing sound. The device may include an elongated strip of material having a ridge substantially extending the length and width of the elongated strip. The elevation of the ridge may vary along the length of the elongated strip to produce sound when contacted by a wheel of a vehicle travelling substantially along the length of the elongated strip.

Abstract: A method, system and device for reproducing sound. The device may include an elongated strip of material having a ridge substantially extending the length and width of the elongated strip. The elevation of the ridge may vary along the length of the elongated strip to produce sound when contacted by a wheel of a vehicle travelling substantially along the length of the elongated strip.

Abstract: An ultrasonic reactor system with an appropriately designed reactor chamber used in conjunction with a compatible ultrasonic Barbell Horn or its derivative that provides a significant efficiency increase and an intensification of sonochemical and sonomechanical processes is disclosed. These enhancements arise from the ability of the reactor chamber to direct all treated liquid media through the highly active ultrasonic cavitation region located near the surface of the horn, as well as from several improvements in the Barbell Horn design that significantly increase its longevity and in its output surface area, thereby increasing the total size of the active cavitation region.

Abstract: A method and apparatus are provided for the controlled application of ultrasonic energy for conditioning of mixtures of gas and liquids by evolving and/or agglomerating gas bubbles existing with or in a liquid or for coalescing droplets of liquid dispersed in another liquid. The invention in preferred embodiments thereof comprises a coalescing apparatus for increasing the droplet size of a mixture formed as a liquid dispersed in another liquid, and a de-gassing apparatus arranged to evolve and/or agglomerate gaseous bubbles in a gas/liquid mixture. In the apparatuses, ultrasonic transducers are used to impart vibrational energy to the mixtures.

Abstract: An acoustic system for applying vibratory energy including a horn connected to an ultrasonic energy source. The horn defines an overall length and wavelength, and at least a leading section thereof is comprised of a ceramic material. The leading section has a length of at least ? the horn wavelength. In one preferred embodiment, an entirety of the horn is a ceramic material, and is mounted to a separate component, such as a waveguide, via an interference fit. Regardless, by utilizing a ceramic material for at least a significant portion of the horn, the ultrasonic system of the present invention facilitates long-term operation in extreme environments such as high temperature and/or corrosive fluid mediums. The present invention is useful for fabrication of metal matrix composite wires.

Abstract: The present invention generally relates to tropical cyclones or hurricanes (typhoons). In one embodiment, the present invention relates to the method of suppressing, mitigating and/or completely eliminating hurricane structures via the destabilizing effect of supersonic booms generated by one or more airplanes capable of supersonic flight (e.g., supersonic-capable fighter planes).

Abstract: An acoustic system for applying vibratory energy including a horn connected to an ultrasonic energy source. The horn defines an overall length and wavelength, and at least a leading section thereof is comprised of a ceramic material. The leading section has a length of at least ? the horn wavelength. In one preferred embodiment, an entirety of the horn is a ceramic material, and is mounted to a separate component, such as a waveguide, via an interference fit. Regardless, by utilizing a ceramic material for at least a significant portion of the horn, the ultrasonic system of the present invention facilitates long-term operation in extreme environments such as high temperature and/or corrosive fluid mediums. The present invention is useful for fabrication of metal matrix composite wires.

Abstract: A pressure wave generator (1) includes a thermally conductive substrate (2), a heat insulating layer (3) formed on one main surface of the substrate (2), an insulator layer (5) formed on the heat insulating layer (3), and a heat generator (4) formed on the insulator layer (5) to generate heat when a current containing an alternating component is applied thereto. The heat insulating layer (3) is formed containing at least one of silicon nitride (Si3N4), silicon dioxide (SiO2), aluminum oxide (Al2O3), magnesium oxide (MgO), diamond crystalline carbon (C), aluminum nitride (AlN), and silicon carbide (SiC). The heat generator (4) is formed containing, for example, gold (Au) or tungsten (W).

Abstract: A method and a loudspeaker construction (10), in which loudspeaker construction spherical acoustic wave fronts emitted by the diaphragms (12) of speaker elements (11) are transformed into a uniform, planar acoustic wave front. The loudspeaker construction (10) comprises a plane wave channel (20), in the surface (26) of which plane wave channel directed towards the diaphragm (12) there are adjacent sound inlet apertures (24) for transmitting acoustic waves into ducts (23) and, on the opposite side (22) of the plane wave channel, there are outlet apertures (25) for transmitting acoustic waves from the ducts into a horn portion (30). The ducts (23) taper so that the width (B) of the outlet apertures located in a row on the side of the horn portion is less than half the diameter (D) of the diaphragm.

Abstract: The invention concerns a sound generator mechanism including a control member (10) and a mechanism (14) for locking/unlocking the control member (10), the control member (10) being able to move between a first position in which the control member is held by the locking/unlocking member (14) and in which it holds the vibrating member (12) away from the rest position thereof, and a second position wherein the control member is released by the locking/unlocking mechanism (14) and wherein it simultaneously releases the vibrating member (12), which starts to vibrate and to produce a sound.

Abstract: A system, device and method for enhancing burning of a solid object in a combustion process is provided where one or more incineration devices (101) for burning a solid object (101), at least one sonic device (301) and wherein said at least one sonic device (301) is a transmitter of high intensity- ultrasound adapted to, during use, apply high intensity ultrasound to said solid object (101) thereby removing ash from said solid object (101) and increasing the speed of the burning of said solid object (101).

Abstract: A method and system supporting the formation and propagation of tunable highly nonlinear pulses using granular chains composed of non-spherical granular systems. Such a method and system may be used to support the creation of tunable acoustic band gaps in granular crystals formed of particles with different geometries (spherical or not) in which the tunability is achieved by varying the static precompression, type of excitation and/or pulse amplitude in the system.

Abstract: A pressure wave generator is provided, which has excellent output stability over time. This pressure wave generator comprises a substrate, a heat generating layer, and a heat insulating layer formed between the substrate and the heat generating layer. A pressure wave is generated in a surrounding medium (air) by a change in temperature of the heat generating layer, which is caused upon energization of the heat generating layer. The heat insulating layer comprises a porous layer and a barrier layer formed between the porous layer and the heat generating layer to prevent diffusion of reactive substances such as oxygen and moisture in the air and impurities into the porous layer. By the formation of the barrier layer, it is possible to prevent a reduction in output of the pressure wave generator caused by a change over time of the porous layer.

Abstract: In an apparatus and method of generating an ultrasonic vibration, an ultrasonic vibration generated in an ultrasonic vibration generator is transmitted through a material layer to control the intensity and the direction of the ultrasonic vibration. In an apparatus and method of cleaning a wafer, a cleaning solution supplier supplies a cleaning solution for cleaning the wafer onto the wafer. An ultrasonic vibration generator generates an ultrasonic vibration. The ultrasonic vibration is transmitted through a material layer of a transmission member to control the intensity and the direction of the ultrasonic vibration. The ultrasonic vibration is applied to the cleaning solution.

Abstract: A system and method for forming acoustic beams is disclosed. One embodiment is an acoustic system configured to generate a plurality of beams non-orthogonal to a transducer array simultaneously with a vertical acoustic beam orthogonal to the array. The acoustic system includes a plurality of transducer elements arranged to form a two-dimensional array and electrically connected into rows in a first dimension and columns in a second dimension.

Abstract: A surround for supporting a diaphragm used to create acoustic waves includes a rib section extending away from the diaphragm and a membrane section that is supported by the rib section. The membrane section has a thickness in a direction substantially normal to opposing top and bottom surfaces of the membrane section which is substantially thinner than a thickness of the rib section in a direction substantially normal to opposing top and bottom surfaces of the rib section. A restoring force returning the diaphragm to a home position is contributed to more due to deformation of the rib section than to deformation of the membrane section.

Abstract: A method is provided for displacing small amounts of fluids in micro channels, in which an amount of fluid is introduced into a channel system which has at least one area which corresponds in a topological manner to a ring, such that a closed path of the fluid is possible, and acoustic waves, which have at least one asymmetrical component on the plane of the channel system, are radiated into the fluid, this component defining the direction of displacement of the fluid. A micro channel system for carrying out the method is also provided.

Abstract: The invention concerns a sound generator mechanism including a control member (10) and a mechanism (14) for locking/unlocking the control member (10), the control member (10) being able to move between a first position in which said control member is held by the locking/unlocking member (14) and in which it holds the vibrating member (12) away from the rest position thereof, and a second position wherein said control member is released by the locking/unlocking mechanism (14) and wherein it simultaneously releases said vibrating member (12), which starts to vibrate and to produce a sound