Abstract: A method for removing tube wave interference from optical fiber acoustic wave sensing seismic data, including: acquiring seismic wavefield data which contains a tube wave and is collected by an optical fiber acoustic wave sensing instrument; calculating a root-mean-square amplitude of the waveform data cut on the seismic trace as an amplitude normalization factor; performing normalization processing on the amplitude value; performing de-tail mean filtering processing on the normalized amplitude value along the travel time of the tube wave, to obtain a predicted amplitude value; performing tube wave interference removal processing on each seismic trace, and performing inverse normalization processing to obtain the seismic wavefield data without tube wave interference. The method effectively suppresses the tube wave interference in the optical fiber acoustic wave sensing seismic data.

Abstract: A method for improving DAS signal-to-noise ratio by means of local FK transform. The method includes: acquiring seismic wavefield data; segmenting the seismic wavefield data into a plurality of pieces of local data, wherein each piece of local data has the same dimension as the seismic wavefield data; processing each piece of local data by means of the following steps: performing FK transform to obtain an intermediate signal, removing some FK spectrum components from the intermediate signal according to scanning energy which corresponds to the intermediate signal under different apparent slowness, and performing two-dimensional inverse FFT on the intermediate signal, from which some FK spectrum components are removed; and combining all the processed local data, so as to obtain new seismic wavefield data.

Abstract: Batteries that include a composite electrode, and a preparation method thereof, and an electrical device are disclosed. An example composite electrode includes a current collector, a first active layer, and a second active layer. The first active layer is disposed on the current collector. The second active layer is disposed on one side, oriented away from the current collector, of the first active layer. The first active layer includes a lithium manganese iron phosphate material. At least a part of a surface of the lithium manganese iron phosphate material is coated with a conductive coating material. A mass of the conductive coating material is 1% to 10% of a mass of the lithium manganese iron phosphate material. The conductivity of the lithium manganese iron phosphate material is improved by the conductive coating material.

Abstract: A VSP-based depth domain seismic profile horizon calibration method includes steps: obtaining VSP wavefield data of a depth domain (S10); determining first arrival time information on the basis of the VSP wavefield data (S20); processing the VSP wavefield data on the basis of a preset filtering method and the first arrival time information to obtain upgoing wave data (S30); generating a zero offset profile of the depth domain on the basis of the upgoing wave data (S40); and calibrating, on the basis of the zero offset profile, a depth-domain profile to be calibrated, so as to generate a corresponding calibration result (S50). Also provided are a VSP-based depth domain seismic profile horizon calibration apparatus and a computer-readable storage medium.

Abstract: A method for inverting a formation wave impedance using DAS borehole seismic data, including: acquiring an initial magnitude at a time window after the initial arrival time of seismic wavefield data in a well; mapping the initial magnitude to a relative wave impedance; and correcting the relative wave impedance to obtain an inverted wave impedance. Also provided are an apparatus for inverting a formation wave impedance using DAS borehole seismic data, a device, and a computer-readable storage medium.

Abstract: A method for correcting imbalance in IQ demodulation of optical fiber DAS data is disclosed. The method includes obtaining I/Q signals I0 and Q0 of each sampling on an optical fiber from a DAS acquisition instrument; performing DC bias correction on the I/Q signals I0 and Q0 to obtain I/Q signals I1 and Q1 after DC bias correction; performing amplitude imbalance correction on the I/Q signals I1 and Q1 after DC bias correction by using Hilbert transform to obtain I/Q signals I2 and Q2 after amplitude imbalance correction; and performing phase imbalance correction on the I/Q signals I2 and Q2 after amplitude imbalance correction by using Hilbert transform to obtain I/Q signals I3 and Q3 after phase imbalance correction. It is possible to perform accurate correction on I/Q signals, accurately and efficiently suppress optical fiber demodulation noise, and improve optical fiber DAS data acquisition quality.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for phone fraud prevention. One of the methods includes adding a first identifier of a first phone event of a first user into a blockchain managed by one or more devices on a decentralized network. The first identifier of the first phone event is classified into a list of phone fraud identifiers. A second identifier of a second phone event involving a second user is received. The second identifier is compared with the list of phone fraud identifiers that includes the first identifier. In a case where the second identifier matches a phone fraud identifier in the list of phone fraud identifiers, the first user is notified that the second phone event involves a risk of phone fraud.

Abstract: A method for global phase IQ Demodulation of optical fiber DAS data includes: acquiring initial optical fiber DAS IQ data from DAS instrument; determining a corresponding direct phase value based on the initial optical fiber DAS IQ data, performing an interrogation pulse phase correction operation on the initial optical fiber DAS IQ data based on the direct phase value to obtain first processed data; performing a receiving point initial phase correction operation on the first processed data to obtain second processed data; performing an interrogation pulse linear phase correction operation on the second processed data to obtain third processed data; performing a receiving point linear phase correction operation on the third processed data to obtain fourth processed data; and performing phase unwrapping processing and de-near DC component processing on the fourth processed data to obtain global phase demodulated data.

Abstract: A battery includes multiple battery cells, each battery cell includes shell, electrode terminal, and insulation layer, the shell includes a first wall, which includes a body and a first convex part, the body has an inner surface and an outer surface arranged oppositely in the thickness direction thereof, the first convex part protrudes from the outer surface in a direction away from the inner part of the battery cells, the electrode terminal is arranged on the body, and the insulation layer covers and is fixed on the first convex part; and a box, provided with an accommodating cavity with an opening, wherein the multiple battery cells are accommodated in the accommodating cavity, and the insulation layer binds with the cover piece covering the opening to fixedly connect the multiple battery cells to the cover piece.

Abstract: A method and device for suppressing interference fading noise of optical fibre sensing data are disclosed. The method contains acquiring optical fibre sensing data not subjected to interference fading noise suppression; determining a fading point amplitude threshold based on the optical fibre sensing data; determining a signal fading point based on the fading point amplitude threshold; performing signal interpolation processing on the optical fibre sensing data corresponding to the signal fading point to obtain a signal subjected to interference fading noise suppression; performing phase demodulation and phase unwrapping processing on the signal subjected to interference fading noise suppression to obtain processed optical fibre sensing data.

Abstract: Disclosed are an improved method and device for calibrating the depth of an optical fibre in a well. The method includes acquiring borehole seismic wave field data based on an optical fibre acoustic wave sensor; determining first arrival time information based on the borehole seismic wave field data; determining a downgoing wave first arrival amplitude based on the first arrival time information and the borehole seismic wave field data; determining an optical fibre amplitude feature point based on the downgoing wave first arrival amplitude; determining a wellhead initial position and a receiving point spacing of the optical fibre in the well based on the optical fibre amplitude feature point and logging curve feature points; and determining depth calibration information of the optical fibre in the well based on the wellhead initial position and the receiving point spacing.

Abstract: A battery cell includes a housing, an electrode assembly accommodated in the housing, and an end cover configured to buckle to an opening of the housing. The end cover comprises a first body part, a first end wall, and a first peripheral wall. The first body part is configured to be connected to the housing. The first end wall is farther away from the electrode assembly than the first body part. The first peripheral wall is disposed around an edge of the first end wall and connected to the first body part, and the first peripheral wall and the first end wall jointly form a first accommodation space used to accommodate at least a part of a tab of the electrode assembly. The first peripheral wall comprises a first arc wall extending from the first end wall to the first body part along a first arc trajectory.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for generating digital marks. One of the methods includes: obtaining entity information of an entity; transmitting the entity information to one or more nodes of a blockchain for storage in the blockchain; obtaining a transaction identification associated with storing the entity information in the blockchain; and generating a digital mark for the entity based at least on the transaction identification.

Abstract: Implementations of this specification provide blockchain-based recording and querying methods and apparatuses. An example method includes operations performed by an access gateway, including receiving, from a first service system, user data including a user identifier of a user; transmitting, to an identifier hash system, a first hash request for the user identifier; receiving, from the identifier hash system, a hash digest of the user identifier; replacing the user identifier in the user data with the hash digest of the user identifier, and packaging the user data into a storage transaction; transmitting, to a blockchain, the storage transaction; receiving, from the blockchain, a result of the storage transaction having been performed by a smart contract published by the first service system on the blockchain; and providing, to the first service system, the result of the storage transaction.

Abstract: A method for extracting a downgoing wavelet and attenuation parameters from VSP data, comprising: performing upgoing and downgoing P-waves separation processing on VSP data to obtain downgoing P-wave data; performing a FFT on seismic data with a preset time window length and cut from the downgoing P-wave data to obtain FFT transformed downgoing P-wave data and a multi-trace downgoing P-wave log spectrum; subtracting a downgoing wavelet log spectrum from the multi-trace downgoing P-wave log spectrum to obtain a wavelet-corrected multi-trace downgoing P-wave log spectrum; performing a correction and an inverse FFT on the FFT transformed downgoing P-wave data to obtain a downgoing wavelet; and obtaining attenuation parameters based on P-wave first arrival time and the parameters of the wavelet-corrected multi-trace downgoing P-wave log spectrum. Also provided are an apparatus for extracting a downgoing wavelet and attenuation parameters from VSP data and a computer device.

Abstract: A method for removing tube wave interference from optical fiber acoustic wave sensing seismic data, including: acquiring seismic wavefield data which contains a tube wave and is collected by an optical fiber acoustic wave sensing instrument; calculating a root-mean-square amplitude of the waveform data cut on the seismic trace as an amplitude normalization factor; performing normalization processing on the amplitude value; performing de-tail mean filtering processing on the normalized amplitude value along the travel time of the tube wave, to obtain a predicted amplitude value; performing tube wave interference removal processing on each seismic trace, and performing inverse normalization processing to obtain the seismic wavefield data without tube wave interference. The method effectively suppresses the tube wave interference in the optical fiber acoustic wave sensing seismic data.

Abstract: A method for extracting a downgoing wavelet and attenuation parameters from VSP data, comprising: performing upgoing and downgoing P-waves separation processing on VSP data to obtain downgoing P-wave data; performing a FFT on seismic data with a preset time window length starting from the P-wave first arrival time and cut from the downgoing P-wave data to obtain FFT transformed downgoing P-wave data and a multi-trace downgoing P-wave log spectrum; subtracting a downgoing wavelet log spectrum from the multi-trace downgoing P-wave log spectrum to obtain a wavelet-corrected multi-trace downgoing P-wave log spectrum; performing, based on parameters of the wavelet-corrected multi-trace downgoing P-wave log spectrum, a correction and an inverse FFT on the FFT transformed downgoing P-wave data to obtain a downgoing wavelet; and obtaining attenuation parameters based on P-wave first arrival time and the parameters of the wavelet-corrected multi-trace downgoing P-wave log spectrum.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for retrieval of values of digital tickets. One of the methods includes receiving a request from a client device for a current value of a digital ticket by a distributing node. The request includes the digital ticket and one or more value changing rules for determining the current value of the digital ticket. The distributing node retrieves a smart contract from a blockchain network in response to the request from the client device. The smart contract includes the one or more value changing rules for determining the current value of the digital ticket. The distributing node determines the current value of the digital ticket based on an original value of the digital ticket and the one or more value changing rules by executing the smart contract, and associates the current value with the digital ticket.

Abstract: A computer-implemented method for blockchain network configuration modification, includes obtaining, by a management client device, modification operation information, where the management client device is a blockchain client device of a blockchain network on which an administrator account is logged in as a logged-in administrator account, and where a user account of the blockchain network comprises at least one administrator account. The management client device constructs a configuration modification transaction including the modification operation information. The configuration modification transaction is signed using the logged-in administrator account. The signed configuration modification transaction is submitted to the blockchain network.

Abstract: Disclosed herein are methods, devices, and apparatuses, including computer programs stored on computer-readable media, for acquiring and recording tracking information on a blockchain. One of the methods includes: verifying, by a terminal device, an identity of a user who is to submit transaction data for recordation on the blockchain; acquiring, by the terminal device, tracking information to be submitted with the transaction data for recordation on the blockchain, the tracking information including identity information of the user and a location of the terminal device; generating, by the terminal device, a data package including the tracking information and the transaction data; and submitting, by the terminal device, the data package for recordation on the blockchain.