In the acoustic object extraction device, beam forming processing units generate a first acoustic signal by beam forming in an arrival direction of a signal from an acoustic object with respect to a microphone array and generate a second acoustic signal by beam forming in an arrival direction of a signal from the acoustic object with respect to a microphone array, and a common component extraction unit extracts, on the basis of a similarity between the spectrum of the first acoustic signal and the spectrum of the second acoustic signal and from the first acoustic signal and the second acoustic signal, a signal containing a common component corresponding to the acoustic object. The common component extraction unit divides the spectrums of the first acoustic signal and the second acoustic signal into a plurality of frequency sections and calculates a similarity for each of the frequency sections.

In the acoustic object extraction device, beam forming processing units generate a first acoustic signal by beam forming in an arrival direction of a signal from an acoustic object with respect to a microphone array and generate a second acoustic signal by beam forming in an arrival direction of a signal from the acoustic object with respect to a microphone array, and a common component extraction unit extracts, on the basis of a similarity between the spectrum of the first acoustic signal and the spectrum of the second acoustic signal and from the first acoustic signal and the second acoustic signal, a signal containing a common component corresponding to the acoustic object. The common component extraction unit divides the spectrums of the first acoustic signal and the second acoustic signal into a plurality of frequency sections and calculates a similarity for each of the frequency sections.

Aspects of the technology described herein relate to ultrasound device circuitry as may form part of a single substrate ultrasound device having integrated ultrasonic transducers. The ultrasound device circuitry may facilitate the generation of ultrasound waveforms in a manner that is power- and data-efficient.

Provided is a filter coefficient optimization technology that makes it possible to design a stable beamformer having a good quality by considering the relationship of a filter coefficient between adjacent frequency bins. A filter coefficient optimization apparatus includes an optimization unit that calculates an optimum value of a filter coefficient w={w.sub.1, . . . , w.sub.F} (w.sub.f is a filter coefficient of a frequency bin f) of a beamformer that emphasizes sound (target sound) from D sound source, a.sub.f,d being an array manifold vector in the frequency bin f corresponding to a sound wave that comes from an angular direction θ.sub.d in which a sound source d exists, the sound wave being a plane wave, the optimization unit calculating the optimum value based on an optimization problem of a cost function defined using a sum of a sum of a cost function L.sub.MV_f(w.sub.f) and a predetermined regularization term, under a predetermined constraint condition, the predetermined regularization term being defined using a difference in phase between adjacent frequency bins relevant to a response w.sub.f.sup.Ha.sub.f,d of the beamformer in the frequency bin f for the angular direction θ.sub.d.

A computer-implemented method for training and using a neural network to predict a coherence function includes: training a neural network by mapping a plurality of different sets of training input samples to respective coherence function truths to generate a trained neural network; receiving an operational input sample; inputting the operational input sample into the trained neural network; obtaining, from the trained neural network, a coherence function mapped to the operational input sample in response to the inputting the operational input sample into the trained neural network; and executing a computer-based instruction based on obtaining the coherence function. The coherence function may be used to differentiate solid masses from fluid-filled masses.

An ultrasound diagnosis apparatus includes a two-dimensional (2D) array ultrasound probe configured to emit focused beams onto focusing points and detect echo signals; and a processor configured to determine the focusing points on a cross-section of interest and acquire shear wave elasticity data with respect to the cross-section of interest based on the detected echo signals.

Provided is a technology of optimizing a latent variable by solving a convex optimization problem equivalent to a non-convex optimization problem instead of solving the non-convex optimization problem. A latent variable optimization apparatus includes an optimization unit that calculates an optimum value ˜w* of a latent variable ˜w based on an optimization problem min.sub.˜w(L.sub.convex(˜w)+Σ.sub.d=1.sup.DL.sub.d(˜w)), L.sub.convex being a strongly convex function relevant to the latent variable ˜w, L.sub.d being a function relevant to the latent variable ˜w, S.sub.d,1, . . . , S.sub.d,C being a region that is obtained by dividing a domain of the function L.sub.d into C closed convex sets, ∧.sub.d,c being a convex function that is defined on the region S.sub.d,c and that approximates the function L.sub.d, c.sub.d being a discrete variable that has a value of 1, . . . , C, the optimization unit calculating the optimum value ˜w* by solving an optimization problem min.sub.c_1, . . . , c_D (min.sub.˜w(L.sub.convex (˜w)+Σ.sub.d=1.sup.D∧.sub.d,c_d(˜w))) instead of solving the above optimization problem.

Systems for magnetoacoustically transferring sound across an acoustic barrier include first and second acoustic resonators positioned on opposite sides of the barrier. Each of the first and second resonators includes an attached magnet. Via magnetic coupling between the magnets, an acoustic oscillation at the first resonator induces an oscillation of the same frequency at the second resonator. Thus sound waves absorbed at the first resonator are magnetically transferred across the barrier to the second resonator, from which they are emitted.

Systems for magnetoacoustically transferring sound across an acoustic barrier include first and second acoustic resonators positioned on opposite sides of the barrier. Each of the first and second resonators includes an attached magnet. Via magnetic coupling between the magnets, an acoustic oscillation at the first resonator induces an oscillation of the same frequency at the second resonator. Thus sound waves absorbed at the first resonator are magnetically transferred across the barrier to the second resonator, from which they are emitted.

Use of ultrasound beams to unlock the perception of mid-air tactile stimuli on hairy skin by using acoustic streaming is described. Such acoustic streaming is directional, more focused than fan and air-puff devices, doesn't require the use of cumbersome attachments, fast since it can be generated at a distance with the speed of sound, and can be used in a complementary fashion with vibrotactile mid-air stimulation deriving from the same hardware. Further proposed is a way to modulate the thermal perception of the mid-air tactile stimuli without the need for a thermal source or wearables. The effect of acoustic streaming and its thermal modulation may be combined for the accurate elicitation of affective touch sensations.