1626 results about "Transverse wave" patented technology

A transcutaneous electrical nerve stimulation device for treating a user's lower back pain or discomfort is provided. The inventive device comprises a stimulation pad with an array of electrodes therein. A controller communicates with the electrodes to energize/de-energize them in a patterned, sequential manner. The patterned actuation of the electrodes in a sequential fashion provides electrical impulses to the patient's skin, simulating a transverse wave motion. The transverse wave motion simulation provides the user with the effect of the electrical stimulation combined with the mechanical tissue stimulation received in traditional massage therapy, resulting in improved pain and discomfort relief. The device may use programs stored in the controller. Alternatively, the user may manually actuate one or more electrodes as well as manually move the electrode actuation to concentrate on a specific lower back region using an electrostatic touch pad or the equivalent. The user may also use voice commands to access the stored programs, move the electrode stimulation region, change the electrode actuation intensity and/or dwell time. The device may store the user's manually-generated routines for repeating when desired. A visual display may provide feedback to the user regarding the electrode actuation position and pattern.

The present invention relates to a shale gas reservoir crustal stress logging prediction method based on a rock physics model. According to the method, a shale gas reservoir rock physics model which takes kerogen particles into consideration is established, so as to predict a longitudinal and transverse wave velocity of the logging; based on the above, a maximum and minimum horizontal principal stress and a fracture pressure of the reservoir are calculated; and an accurate stress assessment of a shale gas reservoir is carried out while a transverse wave logging is not provided. The beneficial effects of the invention are that: the rock physics model in line with characteristics of the shale gas reservoir is established to improve precision of the prediction velocity; and based on the rock physical model, the maximum and minimum horizontal principal stress and the fracture pressure are obtained, so that while the measured transverse wave logging data are not provided, the underground stress can be predicted on the basis of a conventional logging curve, and the prediction result is high in accuracy.

The invention provides a method and a device for synchronous measurements on dynamic and static elastic parameters of rocks by using a rock triaxial anti-compression testing device. The method comprises: sealing a test rock sample in a triaxial autoclave filled with hydraulic oil, applying an oil pressure by an axial pressure control system, applying a confining pressure by a confining pressure control system, and applying a pore pressure by a pore pressure control system; acquiring propagation speeds of longitudinal waves and transverse waves in the test rock sample by a computer acquisition and control system, and calculating the dynamic Young modulus and the dynamic Poisson ratio according to the propagation speeds; and acquiring deformation parameters of the test rock sample during a loading process by the computer acquisition and control system, and calculating the static Young modulus and the static Poisson ratio according to the deformation parameters. The method and the device can ensure validity and accuracy of hydrocarbon reservoir rock mechanical parameter measurements in thousands of meters deep underground and under the conditions of complex confining pressure, high temperature, high pore pressure and polyphase fluid.

A communication device includes a communication circuit unit that processes a high frequency signal which transmits data, a high frequency signal transmission path that is connected to the communication circuit unit, a high frequency coupler that receives the high frequency signal and radiates an induction electric field signal of a longitudinal wave, and an antenna that receives the high frequency signal and radiates a radiation electromagnetic field or an electric wave signal of a transverse wave.

The invention discloses an elastic reverse time migration imaging method by combining seismic multi-component and belongs to the field of exploration geophysics. The method comprises the following steps: directly inputting seismic multi-component data; without performing the wave field separation on the input data, extrapolating forwards at inverse time based on an elastic wave equation; building an underground elastic vector seismic wave field by combining with multi-component; acquiring four elastic wave imaging results having specific physical significance, such as longitudinal wave, transverse wave, transition longitudinal wave and transition transverse wave, by applying an elastic wave cross-correlation imaging condition of lighting compensation; and suppressing the low wave number noise in the elastic reverse time migration by performing low-pass angle filtering, thereby acquiring an imaging result of final elastic wave migration. By directly inputting the seismic multi-component data and building the underground elastic vector seismic wave field by combining with multi-component, the method can be used for accurately imaging for complex earth medium.

A boundary acoustic wave device efficiently traps the vibrational energy of boundary acoustic waves and exhibits a high electromechanical coupling coefficient, and is consequently not affected by higher-order modes. The boundary acoustic wave device includes a first medium having piezoelectric characteristics, a non-electroconductive second medium, and a third medium through which slow transverse waves propagate at a lower acoustic velocity than slow transverse waves propagating through the first and second media. The first medium, the third medium, and the second medium are stacked in that order. An IDT is disposed between the first medium and the third medium. The IDT includes a metal layer made of a metal having a density ρ in the range of about 3000 kg/m³ to about 21500 kg/m³. The IDT has electrode fingers arranged at a pitch of λ and has a thickness H1 satisfying the relationship 0.006λ≦H1≦0.2λ, and the third medium has a thickness H2 satisfying the relationship H1<H2≦0.7λ.

The invention discloses a method suitable for positioning a hydraulic fracturing micro-seismic source. The method includes: building a micro-seismic-monitoring observation system, acquiring logging information and other seismic data, building an initial speed model, researching and analyzing regional stratum conditions and perforation records, determining background interference and micro-seismic signal features, performing noise compression on fracturing records and performing effective waveform identification on micro-seismic signals, and using methods such as first break picking and manual intervention to pick the first break travel time of a direct wave, wherein the travel time of the perforation records is used for optimizing the speed model, and other effective events are used for the inversion positioning of the seismic source. The method has the advantages that transverse wave travel time is added on the basis that longitudinal wave travel time is used, the micro-seismic source is positioned by using the longitudinal wave travel time and the transverse wave travel time to perform simultaneous constraining, the inversion uses a method combining global searching and local searching, and the method is high in positioning precision and high in calculation efficiency.

The invention embodiment discloses a method for shear wave field formation and an ultrasonic image system. The system receives an indication of a region of interest and selects a shear wave front shape. The system also selects, based on the selected shear wave front shape, focus locations for a plurality of push pulses and a sequence for moving a shear wave source among the focus locations. The system transmits a series of push pulses according to the selected sequence, and determines a speed of the shear wave front as it passes through the region of interest. Changes in the speed of the shear wave front are related to changes in stiffness within the tissue.

The invention provides a method for optimizing a design of a vertical seismic profile observation system for seismic exploration, which comprises the following steps: establishing a seismic geological model by known data; distributing more than two different observation systems; forwarding a response of a seismic wave field; calculating a position of a reflective spot, incident and reflection angles and length or ray impact frequency, and counting characteristic parameters again to construct an analysis map; and determining the optimal scheme for actual exploration according to a geological target. The method adopts multi-parameter analysis based on a spacial model, has strong rationality of results, adapts to details, can improve data acquisition quality, is suitable for homogeneous spaces and one-dimensional, two-dimensional or three-dimensional models, can be used for non-zero spacing, Walkaway and 3D-3C VSP exploration designs, and also can be used for analyzing VSP exploration designs of longitudinal waves, transverse waves and converted waves.

The invention relates to a method for imaging an anisotropic medium through utilization of vertical seismic profile data. The method comprises the following steps: firstly, establishing an initial depth-speed model; secondly, establishing an initial speed model through utilization of an interval velocity and an anisotropic coefficient of a Walkaway VSP or three-dimensional VSP first-arrival time inversion model; converting a plane of random normal direction of a three-dimensional space into a plane with normal parallel to the Z axis; loading information of an observation system; determining a reflecting layer of which rays run through from a shooting point to a receiving point; seeking an approximate ray parameter; determining a coordinate of the reflecting point in a reflecting interface and recording the corresponding sequence number of the receiving point; determining the traveling time from the reflecting point to the receiving point and an emergence angle of the ray in the reflecting point; and outputting imaging gather data. The method simplifies calculation, has high operation efficiency, improves the precision and the resolution of the VSP imaging result and can conveniently carry out migration imaging on Walkaway VSP or three-dimensional VSP vertical wave, transverse wave or converted wave data.

The invention relates to a multi-component converted wave static correction method by using surface waves, which comprises a step of solving stratigraphic classification and transverse wave velocity of a superficial layer through the extraction of the surface waves and the inversion of frequency dispersion curves based on Rayleigh surface waves in a shot record, so as to accurately calculate static correction quantity of detection points of converted waves. The test processing on two-dimensional three-component of a certain block in Daqing shows that a transverse velocity non-uniform body of the superficial layer generates a larger static correction time difference; and the processing on three-dimensional three-component data of a certain coal mine in Huainan shows that the static correction time difference of over 20 milliseconds can also occur due to the low and transversely non-uniform transverse wave velocity even in a flat plain terrain, and for a coalfield high-resolution seismic exploration to recognize minor faults of about 3 meters, the static correction time difference is a non-ignorable error. Application tests in three-component seismic data processing in two regions achieve a better processing effect and prove that the multi-component converted wave static correction method by using the surface waves is a feasible method.

The invention discloses a method and device for determining formation pressure. The method includes the steps that amplitude preservation processing is carried out on longitudinal wave PP and converted wave PS seismic data so that superposition data of multiple portions can be obtained, and a longitudinal wave impedance body, a transverse wave impedance body and a density body are obtained in a pre-stack PP and PS joint simultaneous inversion method according to logging information; the longitudinal wave impedance body, the transverse wave impedance body and the density body are converted into depth domains; pressure of overlying strata is calculated according to the density body; effective stress of a framework is calculated according to the longitudinal wave impedance body, the transverse wave impedance body and the density body; the formation pressure is calculated according to the pressure of the overlying strata and the effective stress of the framework. Precision of formation pressure seism prediction can be improved.

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.

An ultrasonic tester of the fastening force for screw bolt is composed of longitudinal wave transducer connected serially to ultrasonic emitter, longitudinal wave receiver and amplifer, transverse wave transducer connected serially to ultrasonic emitter, transverse wave receiver and amplifier, displacement sensor connected serially with thickness measuring circuit, A/D converter and DSP, temp sensor connected serially to temp measuring circuit, A/D converter and DSP, main oscillator, time pulse generator, and ROM. Its feature is use of sono-elasticity principle.

The invention provides a method for determining subsurface fluid by seismic data obtained from geophysical exploration. The method comprises the following steps: converting the seismic data into bulk modulus and density data of the effective subsurface media; acquiring elastic modulus of the effective media at a borehole of a work area according to longitudinal and transverse wave log data; calculating the elastic modulus and the fluid modulus of the media at the borehole, porosity log data and pore aspect ratio spectrum data, low frequency model of solid matrix elastic modulus and the elastic modulus data volume of a dry solid matrix, separating well side fluid bulk modulus from the effective media bulk modulus which is inverted by the seismic data, and calibrating with the moduli of the borehole and well side fluid, and calibrating the moduli of other non-well side fluid by a calibration operator to identify the subsurface fluid. The method makes full use of the amplitude, frequency and phase information to invert the elastic modulus of the effective media, which reduces multi-resolution, breaks though the spherical void restriction and laboratory measurement requirements, and easily achieves the fluid modulus separation, and the fluid identification is direct, the result of the fluid identification is reliable, and the fitness of the fluid identification and well drilling result is up to more than 90%.

The invention discloses a method for determining a fluid by utilizing seismic fluid impedance. The method comprises the following steps: exciting and recording a seismic wave to obtain an angle gather; eliminating signal frequency distortion caused by a normal moveout correction stretching effect; extracting longitudinal wave reflectivity attributes and weighted transverse wave reflectivity attributes from the compensated angle gather; computing improved fluid factors; obtaining logging data to obtain a fluid impedance curve; performing iterative inversion to obtain a section of the fluid impedance; qualitatively analyzing fluid anomalies in pores by the fluid factors, and describing spatial distribution of the fluid by the fluid impedance. The method helps accurately extract the fluid factors and directly identify components of the fluid in the pores without an assumption of a velocity ratio of the longitudinal wave to the transverse wave as well as the relation between density and the longitudinal wave velocity, which reduces ambiguity of gas layer identification, realizes direct conversion from the fluid factors to the fluid impedance and improves the precision of gas reservoir identification.

The invention provides a method for performing joint inversion on the P-wave and S-wave velocity ratio of a reservoir by utilizing P-wave and converted wave data. According to the method, an inversion target function is constructed by adopting a concept that a gamma change rate acquired from gather seismic reflection information and a gamma change rate acquired from travel time information are infinitely approximate, and key parameters of the target function comprise a P-wave intercept, a P-wave gradient, a converted wave gradient and the P-wave and S-wave velocity ratio calculated according to the travel time information, and can be acquired from the actually input amplitude versus offset (AVO) information of a P-wave and converted wave gather and the travel time information, so that the target function can be rationally constructed, and a finally inverted P-wave and S-wave velocity ratio elastic parameter is accurate.

The invention discloses a tunnel boring machine rock breaking seismic source and active source three-dimensional seismic combined advanced detection system. The system comprehensively utilizes two modes of active source seismic source and rock breaking seismic source to perform three-dimensional seismic combined advanced detection, adopts an active source seismic method with high shock energy to realize long distance advanced prediction and positioning recognition of geological anomalous bodies before operation of a tunnel boring machine, performs adjustment and optimization on the following construction of the tunnel boring machine according to a detection result, adopts cutterhead rock breaking vibration with weak shock energy and high ratio of transverse wave components as a seismic source, adopts an unconventional rock breaking seismic source seismic record processing method to realize the real-time short-distance accurate prediction of the geological anomalous bodies, performs representation and evaluation on the quality of surrounding rock in a region to be excavated, finally comprehensively judges the geological condition of a part in front of a working surface according to combined results of active source and rock break seismic source three-dimensional seismic advanced detection, and provides a support for the optimization of tunnel boring machine operating parameters and construction safety control.

The invention discloses an earthquake prediction method for porosity and shale content of a sand shale reservoir. The method comprises steps as follows: measuring test data of a core sample; calculating a matrix elastic parameter according to a rock physical theory; acquiring a longitudinal and transverse wave speed-porosity-shale content theoretical relation of the sand shale reservoir according to the matrix elastic parameter of the sand shale and the test data of the core sample; calculating logging porosity and logging shale content according to acquired actual logging data; on the basis of the longitudinal and transverse wave speed-porosity-shale content theoretical relation, performing parameter cross analysis, and calibrating and correcting the logging speed, the logging porosity and the logging shale content; establishing a quantitative prediction model about logging longitudinal and transverse wave impedance-porosity-shale content; acquiring an earthquake longitudinal wave impedance data cube, a transverse wave impedance data cube and a density data cube through earthquake pre-stack inversion; performing earthquake porosity and shale content data inversion to acquire an earthquake-predicted porosity data cube and an earthquake-predicted shale content data cube.

The invention belongs to the field of exploration geophysics and particularly relates to an elastic seismic wave field forward modeling method. The seismic forward modeling method includes the steps of firstly, according to the principle of wave field vector decomposition, decomposing a seismic wave field into a longitudinal wave field and a transverse wave field and respectively calculating corresponding propagation matrixes of the longitudinal wave field and the transverse wave field; secondly, according to the principle of low-rank decomposition, decomposing the propagation matrixes to obtain propagators of vector longitudinal wave and vector transverse wave so as to reduce calculation amount of numerical simulation to improve calculation efficiency; and thirdly, coupling updated records of the vector longitudinal wave and the vector transverse wave acquired after the numerical simulation so as to obtain a forward modeling result of the seismic wave field. The calculation precision is high due to the fact that the propagation matrixes include compensations to medium parameter and numerical simulation parameter. Numerical dispersion of seismic wave field records acquired by the forward modeling method is nearly eliminated and stability of the numerical simulation is high; accordingly, the forward modeling method is a high-precision elastic wave field numerical simulation method.