摘要:
A receiver section for an acoustic oil well logging tool comprised of a plurality of receiver sub-units connected longitudinally within a rigid tubular member. Each receiver sub-unit has a series of acoustic wave sensors located for receiving and detecting monopole, dipole, quadrupole and unipole waveforms. Separate channels are provided for conveying waveforms data from each receiver sub-unit to an above ground data processing unit. Each receiver sub-unit also includes a compensating sensor for detecting tool vibrations and for producing signals which are combined with waveform data in the processing unit to eliminate the effects of tool vibration.
摘要:
A method for analyzing received wave signal data in an acoustic logging system that includes a logging tool adapted to be moved through a borehole in the earth and comprising a transmitter section and receiver section, wherein the transmitter section produces sonic waves at periodic intervals which are received as wave signal data by the receiver section. The method comprises the steps of processing the received wave signal data using Fourier Transform procedures, filtering the processed data using a Heisenberg filter procedure, using a Hilbert transform to refine the filtered data, and using the refined data to provide a phase velocity analysis.
摘要:
An acoustic formation logging tool includes a transmitter, a receiver, a tube wave absorber, and a digital signal processing section. The transmitter includes an electromagnetic actuator based on capacitive discharge through a coil, producing an intense magnetic pressure which causes an actuator to move into an oil-filled acoustic waveguide. The actuator includes a pusher plate with holes that reduces cavitation and is capable of operation at great depths commonly encountered in oil well logging. Pulse power and spectrum of the acoustic transmitter are sufficient to measure either reflections from distant geological structures or waves propagating through the formation near the borehole. A positive acoustic pulse and a symmetric negative acoustic pulse are generated by action of the actuator on the acoustic waveguide. By directing and diverting the positive and negative pulses, a plurality of acoustic transmitters in a tool provide for operation in a multiplicity of modes: monopole, dipole, quadrupole, and a new unipole mode. The tube wave absorber is provided for attenuating tube wave energy that is propagated in the borehole fluid.
摘要:
A stimulus waveform is processed using a model of the human auditory system to provide a plurality of output waveforms. Each output waveform corresponds to excitation at different locations along the basilar membrane in the cochlea, and matches the narrow frequency bandwidth, short time response, and wave propagation characteristics of the human cochlea. Primary feature detection is achieved by comparing response waveforms and their spatial and time derivatives to predetermined stereotypes. Secondary feature detection is achieved by comparing spatial and temporal patterns of primary features with patterns stereotypical of human speech elements.
摘要:
A powerline sensor including a housing physically and electrically connectable to a powerline; a number of voltage sensing devices spaced peripherally about the housing, each voltage sensing device having an outer plate, an inner plate, and a dielectric material between the inner and out plates, the inner plates electrically connectable to the powerline, the outer plates electrically isolated form the powerline; and circuitry for sensing the voltage potential between the inner and outer plates to determine the voltage on the powerline.
摘要:
In accordance with the present invention, a pulsed induction logging system is provided which includes a logging sonde for traversing a borehole and having downhole microprocessor/controller circuitry in operative contact with a separate host computer/controller at the earth's surface. The host computer/controller and two downhole microprocessor/controllers constitute a network of digital computers and generate a digital pulsed logging code for periodically permitting a radiation coil to be driven by an oscillating current having high peak power. A powerful primary pulse of electromagnetic (EM) energy is periodically generated for irradiating the adjacent formation for induction logging purposes. The sonde also includes an antenna array for detecting secondary induced fields in the formation around the borehole. The array preferably includes a series of grouped, paired coils axially spaced along the borehole. Each group of paired coils independently detects the secondary field. Thereafter each detected signal per group of paired coils, is digitized, reformatted and transmitted to the host computer/controller at the earth's surface. The serially transmitted digital data is highly accurate and capable of frequency domain transformation in situ. After additional processing in the frequency domain, final displays are accurate indications of formation conductivity and/or dielectric values irrespective of adverse formation-borehole effects.
摘要:
Speech signal analysis for data reduction, as stored for synthesis or recognition, is improved by features including: digital spectral analysis; reduction of channel data and bit allocation by selective summation of groups of contiguous data; using the mean average of the log amplitude to find the deviation for each channel; also using the instaneous shape of the mean value for each channel for pairs of adjacent frames, all combined to find a feature ensemble for each pair of adjacent frames.