319 results about "Acoustic radiation" patented technology

A method and apparatus are presented for non-invasively monitoring at least one characteristic of a region of interest in a body. The body is illuminated by pulsed light to induce a photoacoustic effect. Acoustic radiation is detected, and measured data indicative thereof is generated. The photoacoustic effect is controlled by carrying out at least one of the following: providing the pulsed light of at least two different wavelength, analyzing the measured data to determine time variations of at least one predetermined parameter of a time dependent acoustic signal for each of wavelength, and determining oxygen saturation level in the region of interest; and operating a plurality of acoustic elements configured for detection of the acoustic radiation, to thereby define a focal volume for acoustic radiation detection to match dimensions of the region of interest.

Energy is transferred (336) to cause a mechanical property of biological tissue to change, as in ablation. An effect of the transferring is examined in more than one spatial dimension to, for example, make an ablation halting decision for a treatment region, i.e., line (312) or layer (314), or for a location (316) within the region. Halting decisions can be based on lesion-central and / or lesion-peripheral longitudinal displacement of treated tissue evaluated in real time against a characteristic curve. Steering in the azimuthal and / or elevation direction is afforded by, for example, linear, or 2D, multi-channel ultrasound arrays for therapy and imaging. Protocols includable are region-wide scanning (SI 010) and location-by-location completion for both (HIFU) therapy and tracking (acoustic-radiation-forced-based) displacement of treated tissue. Fine, location- to-location monitoring can be used for relatively inhomogeneous tissue; whereas, quicker, sparser and more generalized monitoring (1 100, 1200) can be employed for relatively homogeneous tissue.

The present invention comprises methods and systems that use acoustic radiation pressure.

An instantaneous / real-time wireless dynamic tire pressure sensor (DTPS) for characterizing pavement qualities and for detecting surface and subsurface pavement defects under normal driving conditions. Signal processing provides quantitative assessment of surface conditions. DTPS includes a vehicle tire valve stem-mounted pressure sensor and wheel hub-mounted signal conditioning, amplification, and transmitting circuitry. A signal processing computer within the vehicle is wirelessly coupled to the hub-mounted circuitry. Tire pressure changes caused by ground vibration excitation from the interaction between the tire and pavement at normal driving speeds are detected. When acoustic radiation from a surface wave is significantly stronger than acoustic noise, subsurface information can be extracted. An energy harvester based on strong magnetostatic coupling between a high permeability core solenoid, fixed proximate a vehicle wheel, and a bias magnet array, fixedly mounted in conjunction with a dust shield, can provide power the DIPS.

A measurement system and method are presented for use for non-invasive measurements in a human body. Acoustic radiation is applied to a certain illuminated region in the body, with at least two different conditions of the applied radiation achievable by varying at least one characteristic of the acoustic radiation. Light scattered from the body part is detected, and measured data indicative of detected photons tagged and untagged by the acoustic radiation is generated. The measured data is analyzed to extract therefrom a data portion corresponding to the tagged photons and being therefore associated with a light response of said certain region, thereby enabling determination of tissue properties of said certain region based on a relation between the measured data portions corresponding to the at least two different operating conditions.

The invention provides devices and methods for acoustically assessing the contents of a plurality of reservoirs that are typically provided as an array. An acoustic radiation generator is employed for generating acoustic radiation having an image field of a size sufficient to interrogate a plurality of selected reservoirs at one time. The generator is placed in acoustic coupling relationship via a fluid acoustic coupling medium to the selected reservoirs, and acoustic radiation generated by the generator is transmitted through the coupling medium, an exterior surface of the selected reservoirs, and the selected reservoirs. A characteristic of the transmitted acoustic radiation is analyzed so as to assess the contents of each of the selected reservoirs. Fluid may be ejected from the selected reservoirs according to the assessment. Optionally, a means is provided for removing fluid acoustic coupling medium from the exterior surface after acoustic assessment.

The invention provides a device for controlling the composition and / or volume of a fluid within a reservoir. The device includes a reservoir adapted to contain at least one fluid, a means for monitoring a characteristic of the fluid contained in the reservoir, and a means for introducing additional fluid into the reservoir according to the fluid characteristic monitored by the monitoring means. The device also includes an acoustic generator for generating acoustic radiation. A dispensing means may be provided as well. Other devices and methods that use acoustic radiation to control the composition and / or volume of a fluid within a reservoir are included.

Methods are provided for analyzing characteristics of fluids in the context of an acoustic ejection system. Such a system has a controller, an acoustic radiation generator, and a coupling medium coupling the radiation to a reservoir holding fluid. The methods can use acoustic radiation to both perturb a surface of the fluid in the reservoir and analyze the effect of the perturbation. The methods may use information about prior fluids. The methods of the invention can determine physical characteristics such as speed of sound and viscosity. The methods also include ways to determine a level of acoustic energy suitable to eject a droplet. Preferably the methods are executed automatically under control of programming of a controller of an acoustic ejection system.

A method and system for examining tissue are provided in which the tissue is maintained in a position so that it may be insonified with a plurality of pulsed spherical or cylindrical acoustic waves. The insonifying acoustic waves are scattered by the tissue so that scattered acoustic radiation including a mix of reflected and transmitted acoustic waves is received. A representation of a portion of the tissue is then derived from the received scattered acoustic radiation.

A method and system are presented for use in determining one or more parameters of a subject. A region of interest of the subject is irradiated with acoustic tagging radiation, which comprises at least one acoustic tagging beam. At least a portion of the region of interest is irradiated with at least one electromagnetic beam of a predetermined frequency range. Electromagnetic radiation response of the at least portion of the region of interest is detected and measured data indicative thereof is generated. The detected response comprises electromagnetic radiation tagged by the acoustic radiation. This enables processing of the measured data indicative of the detected electromagnetic radiation response to determine at least one parameter of the subject in a region corresponding to the locations in the medium at which the electromagnetic radiation has been tagged by the acoustic radiation, and outputting data indicative of the at least one determined parameter.

A method and system are presented for use in determining one or more parameters of a subject. A region of interest of the subject is irradiated with acoustic tagging radiation, which comprises at least one acoustic tagging beam. At least a portion of the region of interest is irradiated with at least one electromagnetic beam of a predetermined frequency range. Electromagnetic radiation response of the at least portion of the region of interest is detected and measured data indicative thereof is generated. The detected response comprises electromagnetic radiation tagged by the acoustic radiation. This enables processing of the measured data indicative of the detected electromagnetic radiation response to determine at least one parameter of the subject in a region corresponding to the locations in the medium at which the electromagnetic radiation has been tagged by the acoustic radiation, and outputting data indicative of the at least one determined parameter.

The present invention provides a method making stratified paper by redistributing the pulp suspension inside the headbox nozzle using acoustic radiation waves. Acoustic radiation forces fractionate fibers based on fiber radius. The acoustic radiation waves separate the fibers by pushing the coarse and longer fibers to the inner area while fines and smaller fibers remain in the outer area. This has a similar effect of multi-layer stratification headbox, and provides paper with a smoother surface.

The invention relates to a power flow-boundary element model based elevated rail traffic vibratory-noise simulating and predicting method. The power flow-boundary element model based elevated rail traffic vibratory-noise simulating and predicting method comprehensively considers bridge noise and steel-rail noise of the medium-frequency range (200-1000Hz) in elevated rail traffic, and is higher in noise prediction accuracy than that of a method only considering bridge noise or steel-rail noise. The method includes firstly establishing a rail- bridge system power flow model, calculating input power of bridges and vibration speed of steel rails when harmonic force units different in frequency act on the steel rails; secondly, calculating wheel-rail contact force spectrum under a wheel-rail-bridge coupling system through a wheel-rail combination roughness spectrum so as to obtain vibration states of the bridges and the steel rails under the action of random wheel-rail force; thirdly, respectively establishing an acoustic-radiation two-dimension finite-element-boundary element weak-coupling model for the bridges and the steel rails, and calculating vibration power and radiation sound field under the action of the harmonic force units at different frequencies; finally, acquiring practical vibration power by the power flow method and vibration power by the finite-element-boundary element model, scaling field-point sound pressure under the action of unit force to obtain the bridge noise, the steel-rail noise and the total noise thereof.

The invention provides devices and methods for acoustically assessing the contents in a plurality of reservoirs. Each reservoir has a portion adapted to contain a fluid, and an acoustic radiation generator is positioned in acoustic coupling relationship to each of the reservoirs. Acoustic radiation generated by the acoustic radiation generator is transmitted through at least the portion of each reservoir to an analyzer. The analyzer is capable of analyzing a characteristic of the transmitted acoustic radiation and optionally correlating the characteristic to a property of the reservoirs' contents. The invention is particularly suited for assessing the contents of a plurality of reservoirs to allow for accuracy and control over the dispensing of fluids therefrom.

The invention relates to a high-power radial vibration piezoelectric ultrasonic transducer suitable for liquid ultrasonic treatment under normal pressure and high pressure. The purpose of the present invention is to provide a high structural strength, high power density, which can generate uniform sound radiation in the radial direction of 360°, aiming at the defects of low structural strength and low power density of existing ultrasonic transducers, It is a high-power radial vibration piezoelectric ultrasonic transducer especially suitable for liquid ultrasonic treatment under normal pressure and high pressure. The invention comprises a piezoelectric ceramic disc, a prestressed annular cover plate, a cylinder body, an insulating vibration-isolating ring pad and an end cover, wherein a through hole is arranged on the piezoelectric ceramic disc, and the side of the piezoelectric ceramic disc and the prestressed annular cover plate The composite disk piezoelectric transducer is formed by radial compounding. Several composite disk piezoelectric transducer units whose geometric parameters are consistent with the radial resonance frequency are connected in electrical parallel, and are closely fixed on the inner wall of the cylinder at equal intervals. An insulating vibration-isolating ring pad is arranged between two adjacent composite disc piezoelectric transducer units.

To ensure the same high quality of acoustic radiation from audio systems on each seat of current vehicles, an acoustic device is provided for generating audio signals, which allows sound sources to be integrated into the area located near the headrest of a vehicle seat such that the volume can be regulated in an individual manner without unduly disturbing the other passengers in a vehicle. The headrest does not comprise any loudspeakers, thus is safe regarding accident protection. The acoustic near field at the headrest is generated by means of a sound channel. The loudspeaker is disposed inside the backrest or under the seat, for example, while the sound channel terminates in the headrest. Tuned pipes, the end of which is adjusted to the acoustic impedance of the clearance zone, are used as a sound channel.

Disclosed is a system for controlling acoustic radiation from an aircraft. The system comprising a plurality of rotor systems (one or more) and a noise controller configured to regulate acoustic radiation from the plurality of rotor systems. The noise controller can be configured to regulate a commanded flight setting from the flight control system and to output a regulated flight setting to the plurality of rotor systems. Based on the regulated flight setting, the plurality of rotor systems are configured to generate, individually and in aggregate, acoustic radiation having a target acoustic behavior. The target acoustic behavior may be achieved using beamforming techniques to, for example, change the directionality of acoustic radiation from the plurality of rotor systems, or otherwise tune the acoustic radiation to reduce detectability and / or annoyance.

The disclosed technology describes compositions and methods useful for providing cell based therapy. For example, one embodiment of cell based therapy involves the regeneration of injured tissue and / or promoting wound healing. Certain embodiments provide improved therapeutic compositions using microbubbles by delivering biological progenitor cells to the injured tissues. The administration of the microbubbles is directed by acoustic radiation forces that interact with embodiments of microbubbles comprising an acoustically active gas. As such, a high efficiency of progenitor cell delivery to injured tissue is realized. One advantage of this technique over targeted delivery of pharmaceutical compounds, is that the delivered progenitors cells may be derived from the patient (i.e., personalized therapy), thereby avoiding side effects, allergic reactions, and overall problems associated with refractive drug responses.

General algorithms are developed for reconstructing the acoustic field generated by an arbitrary object subject to an arbitrarily time-dependent excitation. These algorithms enable one to visualize a time-domain acoustic pressure wave as it travels through three-dimensional space. Such a tool can be used to diagnose general noise sources and transmission since in engineering applications most structures are subject to arbitrarily time-dependent excitations. To facilitate the derivations of the temporal solutions, we make use of Laplace transform and expand the acoustic pressure in terms of the spherical Hankel functions and the spherical harmonics. The expansion coefficients are settled by solving an over-determined system of equations obtained by matching the assumed-form solutions to the measured acoustic pressures. To obtain a general expression for a temporal kernel, we replace the spherical Hankel functions by polynomials in s, recast the infinite integral in the inverse Laplace transform as a contour integral in the complex s-plane, and evaluate it via residue theorem. Once this is done, the transient acoustic quantities anywhere including a source surface can be obtained by convoluting the temporal kernels with respect to measured acoustic pressures.

The present invention achieves the wideband operation of a bolted Langevin-type echo sounder transducer by enabling low frequency operation with securing a sound pressure level above a certain level without changing the external dimensions of the echo sounder transducer. This is an echo sounder transducer includes a Langevin-type vibrator having a front mass and a rear mass, and a cylindrical active vibrator which is sandwiched between the front mass and rear mass, a bend vibrator constituted of a diaphragm arranged in an acoustic radiation surface section of the front mass of the Langevin-type vibrator, and a disc type active vibrator fixed to the diaphragm. This has such structure that a slit, communicating from an outer peripheral side face toward an axial center, is provided on the circumference in the side of the lower portion of the front mass of the Langevin-type vibrator toward the rear mass.

The aim of the invention is to ensure the same high quality of acoustic radiation from audio systems on each seat of current vehicles. Said aim is achieved by a novel acoustic device for generating audio signals, which allows sound sources to be integrated into the area located near the headrest of a vehicle seat such that the volume can be regulated in an individual manner without unduly disturbing the other passengers in a vehicle, who hear the audio signals to a significantly reduced extent. The headrest does not comprise any loudspeakers, thus offering good creative possibilities regarding accident protection and design. The acoustic near field at the headrest is generated by means of a sound line. The loudspeaker is disposed inside the backrest or under the seat, for example, while the sound line terminates in the headrest. Tuned pipes, the end of which is adjusted to the acoustic impedance of the clearance zone, are used as a sound line.

A medical ultrasound device is disclosed. The device comprises an elongated body having a proximal end and a distal end region (1). One or more ultrasound transducers (4) for generating acoustic radiation are positioned in the distal end region, inside the elongated body. A transmission element (5) which is substantially transparent to acoustic radiation is positioned in the radiation path of the acoustic radiation, and a controller unit is operatively connected to the ultrasound transducer. The transmission element and the one or more ultrasound transducers are mounted so that an acoustic path length (8) between the transmission element (5) and the ultrasound transducer (4) varies with contact force (10) imposed to the distal end region. The controller unit detects the acoustic path length between the ultrasound transducer and the transmission element and determines the contact force from the detected acoustic path length. In an embodiment, the medical device is an ultrasound RF ablation catheter.

The invention provides a piezoelectric underwater sound transducer acoustic radiation mode measurement method and system based on combination near-field acoustical holography. In the method, the combination near-field acoustical holography is utilized to reestablish sound field, sound pressure and radiation surface vibration velocity; on the basis of an acoustic radiation operator matrix obtained based on measurement data and with the sound field radiation theory being combined, the acoustic radiation power of a piezoelectric underwater sound transducer is expressed to be a positive definite quadric form; and positive definite and conjugate performance of the matrix are utilized to obtained an acoustic radiation mode of the structure. The system comprises a glass water tank, an industrial control computer with PXI bus, a transducer excitation module based on the PXI bus, a sound pressure and vibration velocity acquisition module and a three-dimensional motion platform. The method and system in the invention break the limitation that acoustic radiation mode in the current complex underwater structure can only be solved numerically, provide a new idea for research on the piezoelectric underwater sound transducer, and also provide basis for structure optimization of the piezoelectric underwater sound transducer.

A measurement system and method are presented for use for non-invasive measurements in a human body. Acoustic radiation is applied to a certain illuminated region in the body, with at least two different conditions of the applied radiation achievable by varying at least one characteristic of the acoustic radiation. Light scattered from the body part is detected, and measured data indicative of detected photons tagged and untagged by the acoustic radiation is generated. The measured data is analyzed to extract therefrom a data portion corresponding to the tagged photons and being therefore associated with a light response of said certain region, thereby enabling determination of tissue properties of said certain region based on a relation between the measured data portions corresponding to the at least two different operating conditions.

A method for treating a medical pathology includes receiving a first set of acoustic radiation scattered by a volume of tissue containing at least a portion of the medical pathology and thereafter, changing a temperature of the volume of tissue. The method also includes thereafter, receiving a second set of acoustic radiation scattered by the volume of tissue and localizing the portion of the medical pathology from the first and second sets of received acoustic radiation. Localizing the portion of the medical pathology comprises identifying the medical pathology from differences in the first and second sets of received acoustic radiation resulting from the change in temperature. The method also includes insonifying the portion of the medical pathology with sufficient energy to damage the portion of the medical pathology.

The invention provides devices and methods for acoustically determining the properties of the contents of one or more reservoirs in a plurality of reservoirs. Each reservoir is adapted to contain a fluid. An acoustic radiation generator can be positioned in acoustic coupling relationship to each of the reservoirs. Acoustic radiation generated by the acoustic radiation generator is transmitted through each reservoir to an analyzer. The analyzer is capable of analyzing a characteristic of the transmitted acoustic radiation and optionally correlating the characteristic to a property of the reservoirs' contents. Properties that may be determined include volume, temperature, and composition. The invention is particularly suited to determining the properties of the contents of a plurality of reservoirs to allow for accuracy and control over the dispensing of fluids therefrom.

The invention discloses a method for calculating the electromagnetic vibration noise of a motor, which comprises the following steps: calculating the distribution of the electromagnetic force densityof the motor according to the operation condition of the motor, and calculating the static deformation and the natural frequency of the motor respectively; according to the distribution of the electromagnetic force density, the electromagnetic resultant force on the stator teeth of the motor is calculated, and the time-space harmonic of the electromagnetic resultant force is calculated. The frequency response function of the motor structure corresponding to each vibration mode is calculated according to the natural frequencies of each vibration mode corresponding to each spatial order of the electromagnetic force, and the transfer function of the motor mechanical structure is calculated according to the static deformation function and the frequency response function. The vibration displacement of the motor surface is calculated according to the time-space harmonics and the transfer function. The modal acoustic radiation efficiency of the motor housing is obtained, and the electromagnetic vibration noise of the motor is calculated according to the modal acoustic radiation efficiency and vibration displacement. In the process of analyzing the vibration and noise of the motor, the invention ensures that the calculation accuracy meets the precision requirement, and reduces the calculation amount to avoid consuming a large amount of calculation resources.