113 results about "Elastic wave propagation" patented technology

A piezoelectric thin film of the present invention includes an aluminum nitride thin film that contains scandium. A content ratio of scandium in the aluminum nitride thin film is 0.5 atom % to 50 atom % on the assumption that a total amount of the number of scandium atoms and the number of aluminum atoms is 100 atom %. According to this arrangement, the piezoelectric thin film of the present invention can improve a piezoelectric response while keeping characteristics of elastic wave propagation speed, Q value, and frequency-temperature coefficient that the aluminum nitride thin film has.

A piezoelectric thin film of the present invention includes an aluminum nitride thin film that contains scandium. A content ratio of scandium in the aluminum nitride thin film is 0.5 atom % to 50 atom % on the assumption that a total amount of the number of scandium atoms and the number of aluminum atoms is 100 atom %. According to this arrangement, the piezoelectric thin film of the present invention can improve a piezoelectric response while keeping characteristics of elastic wave propagation speed, Q value, and frequency-temperature coefficient that the aluminum nitride thin film has.

The invention relates to a method and a device for the ultrasonic and nondestructive detection of the elasticity of a viscoelastic medium, which belong to the technical field of nondestructive measurements. The method comprises the following steps of: using an ultrasonic probe to produce low-frequency vibration on a medium to be detected, emitting ultrasonic waves to the medium to be detected and acquiring an ultrasonic signal returned from the medium to be detected; selecting an ultrasonic signal range for calculating the elasticity of the medium to be detected; using the selected ultrasonic signal to calculate the transmission speed of an elastic wave produced by the low-frequency vibration in the medium and further calculating the medium elasticity according to the obtained transmission speed of the elastic wave. The device comprises an ultrasonic wave energy converter contact, a vibrator fixing the ultrasonic wave energy converter contact and a control device. In the method and device, motion compensation of the ultrasonic probe is not required, so that calculation time is shortened; meanwhile, position detection is carry out without a position sensor, so that the system complexity and cost are lowered.

The invention provides an apparatus and method for stimulating a borehole of a well. The invention provides an apparatus that generates low-frequency seismic type elastic waves that propagate to the geologic formation and in order to enhance the movement of fluids in the geologic formation toward a well. The apparatus may operate automatically driven by a power source that may be located on the ground surface. The regime of operation may be determined by user input. Operation of the apparatus may carried out while production of a natural resource is ongoing.

A quadplexer includes a first filter and a second filter having a pass band frequency that is higher than a pass band frequency of the first filter. The first filter includes series resonators disposed on a first path and parallel resonators disposed on a path that connects the first path and a ground to each other. A direction that connects ends of a plurality of electrode fingers defining each resonator crosses an elastic wave propagation direction at a predetermined angle. The series resonator nearest to a common terminal does not include first electrode fingers, and the other series resonators include the first electrode fingers.

A vibratory sensor is fabricated as a three-dimensional batch-micromachined shell adapted to vibrate and support elastic wave propagation and wave precession in the shell or membrane and at least one driving electrode and preferably a plurality of driving electrodes directly or indirectly coupled to the shell to excite and sustain the elastic waves in the shell. The pattern of elastic waves is determined by the configuration of the driving electrode(s). At least one sensing electrode and preferably a plurality of sensing electrodes are provided to detect the precession of the elastic wave pattern in the shell. The rotation of the shell induces precession of the elastic wave pattern in the shell which is usable to measure the rotation angle or rate of the vibratory sensor.

A quadplexer includes a first filter and a second filter having a pass band frequency that is higher than a pass band frequency of the first filter. The first filter includes series resonators disposed on a first path and parallel resonators disposed on a path that connects the first path and a ground to each other. A direction that connects ends of a plurality of electrode fingers defining each resonator crosses an elastic wave propagation direction at a predetermined angle. The series resonator nearest to a common terminal does not include first electrode fingers, and the other series resonators include the first electrode fingers.

A method and apparatus for estimating a porosity and a saturation in a subsurface reservoir. The method includes determining a plurality of mathematical relationships relating a plurality of fundamental physical parameters that govern elastic wave propagation in the subsurface reservoir to the porosity and the saturation in the subsurface reservoir, forward modeling a plurality of seismic attributes using the mathematical relationships to derive a plurality of conditional probability density functions for the seismic attributes, applying a Bayesian inversion to the conditional probability density functions for the seismic attributes to derive a joint probability density function for the porosity and the saturation in the subsurface reservoir, and integrating the joint probability density function for the porosity and the saturation to derive a probability density function for the porosity and a probability density function for the saturation.

The invention belongs to the field of exploration earth physics and specifically relates to an elastic vector reverse time migration imaging method. According to the invention, multi-component seismic data is used as input, an elastic wave propagation operator is utilized to carry out wave field prolongation, an elastic vector seismic wave field is constructed; and a decoupling prolongation equation method is utilized to obtain longitudinal and transverse wave fields of decoupling; vector points of the longitudinal and transverse wave fields with seismic source illumination compensation are utilized to construct elastic wave cross-correlation imaging conditions, and a multi-component seismic data elastic vector reverse time migration imaging result is obtained; and low-frequency noise suppression is carried out on the imaging result, and a final elastic vector reverse time migration imaging result is obtained. The elastic vector reverse time migration imaging method solves the scalar imaging problem of the longitudinal and transverse wave fields, and the imaging precision of elastic reverse time migration under a complex construction is improved.

The invention relates to a piezoelectric thin film, a piezoelectrics and manufacturing method thereof, a piezoelectrics harmonic oscillator, a actuator element and a phsical sensor. A piezoelectric thin film of the present invention includes an aluminum nitride thin film that contains scandium. A content ratio of scandium in the aluminum nitride thin film is 0.5 atom % to 50 atom % on the assumption that a total amount of the number of scandium atoms and the number of aluminum atoms is 100 atom %. According to this arrangement, the piezoelectric thin film of the present invention can improve a piezoelectric response while keeping characteristics of elastic wave propagation speed, Q value, and frequency-temperature coefficient that the aluminum nitride thin film has.

A filter device includes a longitudinally coupled resonator elastic wave filter that includes IDT electrodes including low acoustic velocity regions in outer side portions of center regions of the IDT electrodes and high acoustic velocity regions in outer side portions of the low acoustic velocity regions in a direction orthogonal or substantially orthogonal to an elastic wave propagation direction, and defines and functions as a first bandpass filter, and elastic wave resonators that are electrically connected to the longitudinally coupled resonator elastic wave filter.

A method and apparatus for estimating a porosity and a saturation in a subsurface reservoir. The method includes determining a plurality of mathematical relationships relating a plurality of fundamental physical parameters that govern elastic wave propagation in the subsurface reservoir to the porosity and the saturation in the subsurface reservoir, forward modeling a plurality of seismic attributes using the mathematical relationships to derive a plurality of conditional probability density functions for the seismic attributes, applying a Bayesian inversion to the conditional probability density functions for the seismic attributes to derive a joint probability density function for the porosity and the saturation in the subsurface reservoir, and integrating the joint probability density function for the porosity and the saturation to derive a probability density function for the porosity and a probability density function for the saturation.

Provided is a highly reliable elastic wave device wherein deterioration of electrical characteristics due to deformation of a protection cover is suppressed. A method for manufacturing such elastic wave device is also provided. The elastic wave device is provided with a piezoelectric substrate (1) for propagating an elastic wave; an excitation electrode arranged on a first main surface of the piezoelectric substrate (1); a columnar electrode (10) for connecting to the external, which is electrically connected to the excitation electrode; a protection cover (17), which has a hollow storing space (8) for storing the excitation electrode and is arranged on the first main surface; and a conductor layer (18), which is arranged on the protection cover (17) and is connected to the electrode (10).

An elastic wave device includes an IDT provided on a piezoelectric substrate. The IDT includes edge areas in which an elastic wave propagation velocity is slower than an elastic wave propagation velocity in a center area of an electrode finger intersecting region. The edge areas are provided on both sides of the center area in an intersecting width direction. The IDT includes a first section where the propagation velocity in the center area is relatively fast and a second section where the propagation velocity in the center area is relatively slow in the elastic wave propagation direction. In accordance with the propagation velocities in the center areas of the first and second sections, the widths and propagation velocities in the edge areas of the first and second sections excite a piston mode.

A vibratory sensor is fabricated as a three-dimensional batch-micromachined shell adapted to vibrate and support elastic wave propagation and wave precession in the shell or membrane and at least one driving electrode and preferably a plurality of driving electrodes directly or indirectly coupled to the shell to excite and sustain the elastic waves in the shell. The pattern of elastic waves is determined by the configuration of the driving electrode(s). At least one sensing electrode and preferably a plurality of sensing electrodes are provided to detect the precession of the elastic wave pattern in the shell. The rotation of the shell induces precession of the elastic wave pattern in the shell which is usable to measure the rotation angle or rate of the vibratory sensor.

In an elastic wave device, low acoustic velocity portions are provided on both sides of an IDT center portion in an intersection region of an IDT electrode and high acoustic velocity portions are provided outside of the low acoustic velocity portions in an electrode finger direction. Thus, a piston mode is able to be utilized. The widths of the high acoustic velocity portions in end portions of the IDT electrode in an elastic wave propagation direction are relatively smaller than the widths of the high acoustic velocity portions in the center of the IDT electrode in the elastic wave propagation direction.

The invention provides an apparatus and method for stimulating a borehole of a well. The invention provides an apparatus that generates low-frequency seismic type elastic waves that propagate to the geologic formation and in order to enhance the movement of fluids in the geologic formation toward a well. The apparatus may operate automatically driven by a power source that may be located on the ground surface. The regime of operation may be determined by user input. Operation of the apparatus may carried out while production of a natural resource is ongoing.

An object of the present disclosure is to provide an elastic wave resonator having a high Q value, and producing little or no unwanted spurious signals. In order to achieve the object, an elastic wave resonator according to the present disclosure includes a piezoelectric substrate and an IDT electrode. The IDT electrode has an apodization-weighting portion in which a staggered section width decreases toward an end portion of the IDT electrode in an elastic wave propagation direction. The electrode finger pitch of the IDT electrode decreases toward an end portion of the IDT electrode in an end portion, in the elastic wave propagation direction, of a staggered region of the IDT electrode.

To enhance a heat dissipation property and achieve stabilization of a resonance characteristic in an elastic wave resonator including an IDT electrode weighted so as to have a plurality of apodization local maximum value portions, the elastic wave resonator includes an IDT electrode located on a piezoelectric substrate, the IDT electrode is apodization-weighted so that a plurality of local maximum values occur in apodization in an elastic wave propagation direction, heat dissipation electrodes are provided in at least one apodization local minimum value portion occurring in the elastic wave propagation direction in the IDT electrode, and when it is assumed that direction dimension widths of the heat dissipation electrodes in the elastic wave propagation direction are A and the dimension of about ½ of a wave length of a propagating elastic wave is B, B<A is satisfied.

A longitudinally coupled resonator-type surface acoustic wave filter includes a low acoustic velocity film and a piezoelectric film stacked over a high acoustic velocity component in which a bulk wave propagates at an acoustic velocity higher than an acoustic velocity of an elastic wave that propagates in the piezoelectric film. IDT electrodes are provided on one surface of the piezoelectric film. The longitudinally coupled resonator-type surface acoustic wave filter uses a SH wave. At least one of the IDT electrodes has a duty factor that is adjusted over an entire length of the one of the IDT electrodes in the direction of elastic wave propagation to suppress a Rayleigh wave spurious response.

The invention discloses a multi-grid Chebyshev parallel spectral element method. The method includes the steps that a, a calculation area is divided into large and regular units; b, main grids and auxiliary grids are defined in the units, and the main grids are Chebyshev collocation points; c, Wave fields in the units are subjected to Chebyshev truncation expansion by the utilization of the main grids, and medium parameters and external forces in the units are subjected to truncation expansion by the utilization of the auxiliary grids; d, wave field, medium parameter and external force truncation expansion formulas are substituted into a wave equation to obtain unit mass matrixes, unit stiffness matrixes and unit external force vectors; e, on the basis of the unit mass matrixes, the unit stiffness matrixes and the unit external force vectors, an elastic wave expansion is solved on the main grids.

The invention relates to an elastography control method. The method comprises: obtaining an ultrasonic image corresponding to a to-be-detected material; Performing image segmentation on the ultrasonicimage to obtain a plurality of image units; Acquiring an imaging area of a target tissue in the ultrasonic image according to the plurality of image units; If the imaging area of the target tissue issmaller than a preset area threshold value, generating first warning information, Wherein the first warning information is used for indicating to change the position of the probe or the position of the focus. The elastic imaging is carried out by adopting the mode, so that the to-be-measured material meets the rigid requirement of uniformity, and the influence of heterogeneity and material boundary on elastic wave propagation during measurement is avoided, therefore, the image quality of elastic imaging is improved, and the measured data is more accurate. The invention further relates to an elastic imaging control device, computer equipment, a computer readable storage medium and an elastic imaging system.

A seismic wave source and sensing system coupled to the surface of an elastic wave propagation medium has a seismic wave source transducer having a preferred axis of vibration oriented horizontally on the surface of the elastic wave propagation medium. A seismic wave sensing transducer has a preferred axis of vibration response oriented horizontally on the surface of said elastic wave propagation medium such that said sensing transducer is capable of detecting dynamic particle motions and displacements of SH waves. An arrangement of the source and sensing transducers is provided on the surface of the elastic wave propagation medium. A recording system capable of acquiring and storing reflected SH wave signals detected by the sensing transducer, wherein the recorded signals represent reflections from contrasting physical properties within the elastic wave propagation medium to provide preferential detection of elongate subsurface targets such as utility pipes, conduits, and other similar object.

The invention discloses a method for detecting shield channel influence area karst under a building. A horizontal directional drilling machine is utilized to horizontally drill holes in the peripheryof a channel to be built, then in a receiving well, an ultrasonic wellbore imager performs cross-hole pullback in drill holes as an acoustic source, and cross-hole acoustic waves acquired by the ultrasonic wellbore imager are acquired through a data acquisition instrument to form CT input data; and acoustic wave tomographic inversion is performed on the CT input data, mapping software is utilizedto display a cross-hole acoustic wave tomographic map, and finally, a karst distribution situation in a channel range under the building is analyzed based on acoustic wave velocity difference of a detection target and surrounding rock thereof and an attenuation law in an elastic wave propagation process. The karst detection method can overcome limitation of site conditions, an anti-interference capability is high, detection precision and resolution are high, a karst development situation in the subway tunnel range under the building can be precisely detected, risks of construction of the tunnel underneath passing the building are reduced, and the method has good social benefits and economic benefits.

A ladder filter including a series arm resonator and a parallel arm resonator disposed on the same common piezoelectric substrate achieves improved miniaturization. The ladder filter includes series arm resonators and parallel arm resonators, which include elastic wave resonators, and are disposed on the same common piezoelectric substrate, at least one parallel arm resonator of the series arm resonators and the parallel arm resonators includes a first resonator and a second resonator electrically connected in parallel to each other, and the first resonator and the second resonator are arranged in parallel or substantially in parallel in a direction perpendicular or substantially perpendicular to an elastic wave propagation direction, on one side outside one series arm resonator of remaining resonators in the elastic wave propagation direction thereof.

An elastic wave device includes a piezoelectric substrate including an IDT electrode provided on one main surface. In the elastic wave device, a center region positioned in a central portion in a direction perpendicular to an elastic wave propagation direction, first and second low acoustic velocity regions positioned outside of the center region, and first and second high acoustic velocity regions positioned outside of the first and the second low acoustic velocity regions in plan view are provided. A groove portion overlaps with one of the first electrode finger and the second electrode finger in plan view in a portion located in the first and second low acoustic velocity regions on the main surface. An acoustic velocity adjusting layer is provided in the groove portion.

An elastic wave includes a piezoelectric substrate having a polarization direction denoted by an arrow Px, and first and second IDT electrodes arranged on the substrate in an elastic wave propagation direction with a shared reflector therebetween. A first bus bar of the first IDT electrode and a first end portion bus bar of a second reflector are connected to a wiring electrode to define a first terminal. A second bus bar of the first IDT electrode and a second end portion bus bar of the shared reflector are connected to each other to define a second terminal. A first end portion bus bar and a first bus bar are electrically connected to each other. A second bus bar and a second end portion bus bar are electrically connected to each other, and the first and second IDT electrodes and are connected in parallel between the first and second terminals.

A ladder filter device includes elastic wave resonators with IDT electrodes. An apodization angle θ in an IDT electrode of a series arm resonator in the ladder filter device falls within a range from about 2° to about 14° with respect to an elastic wave propagation direction. This arrangement provides a ladder filter device that has a smaller insertion loss in a low frequency side portion of a passing band.

An object of the present disclosure is to provide an elastic wave resonator having a high Q value, and producing little or no unwanted spurious signals. In order to achieve the object, an elastic wave resonator according to the present disclosure includes a piezoelectric substrate and an IDT electrode. The IDT electrode has an apodization-weighting portion in which a staggered section width decreases toward an end portion of the IDT electrode in an elastic wave propagation direction. The electrode finger pitch of the IDT electrode decreases toward an end portion of the IDT electrode in an end portion, in the elastic wave propagation direction, of a staggered region of the IDT electrode.