Abstract: A method for calculating a position or an angle of an inspection target based on a sine wave signal and a cosine wave signal output from an encoder or a laser interferometer, includes acquiring a temporary movement speed of the inspection target, calculating an amplitude correction value corresponding to the temporary movement speed using information representing a relationship between a movement speed of the inspection target and amplitudes of the sine wave signal and the cosine wave signal acquired in advance, correcting the amplitudes of the sine wave signal and the cosine wave signal using the amplitude correction value, and calculating an offset error in a Lissajous waveform using the sine wave signal and the cosine wave signal the amplitudes of which are corrected with the amplitude correction value and calculating the position or the angle of the inspection target using the offset error.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for performing electron paramagnetic resonance (EPR) spectroscopy on a fluid from a flowing well, such as fluid from hydrocarbon recovery operations flowing in a downhole tubular, wellhead, or pipeline. One example method generally includes, for a first EPR iteration, performing a first frequency sweep of discrete electromagnetic frequencies on a cavity containing the fluid; determining first parameter values of reflected signals from the first frequency sweep; selecting a first discrete frequency corresponding to one of the first parameter values that is less than a threshold value; activating a first electromagnetic field in the fluid at the first discrete frequency; and while the first electromagnetic field is activated, performing a first DC magnetic field sweep to generate a first EPR spectrum.

Abstract: An electrical resistivity tomography system having a novel electrode geometry and method of use is provided. The novel electrode geometry radiates a uniform electric field which produces greatly improved resistivity data.

Abstract: A detection device, an inverter, and a detection method are disclosed. The detection device is configured to detect a leakage current flowing through a conductor. The detection device includes a magnetic core, a detection winding and a calibration winding both wound on the magnetic core, a detection circuit, and a calibration circuit. The detection circuit is coupled to the detection winding, and configured to sample a detection signal of the detection winding to obtain a leakage current detection value. The calibration circuit is coupled to the calibration winding, and configured to provide a calibration signal to the calibration winding.

Abstract: An aspect of the invention relates to a method for correcting magnetometric measurements (10) made by a magnetometer mounted on a mobile support. The mobile support carries one or more movement and/or position sensors fixedly mounted with respect to the magnetometer.

Abstract: A nanodevice provides for electric-field control of magnon-QSD interactions. The nanodevice includes a ferroelectric substrate, a ferromagnetic material disposed over the ferroelectric substrate, and a nanodiamond including an ensemble of nitrogen-vacancy (NV) spins, each NV magnetically interfacing with the ferromagnetic material. An electric field is measured by applying a voltage across the ferroelectric substrate and the ferromagnetic material, changing a magnon excitation spectrum of the ferromagnetic material with respect to an electron spin resonance frequency of the ensemble of NV spins, and measuring a relaxation rate of the ensemble of NV spins.

Abstract: Methods and systems are provided for characterizing formation water salinity of subsurface formation using multifrequency permittivity data over a range of frequencies below 1 MHz. The multifrequency permittivity data is processed to determine salinity of formation water contained in the subsurface formation. Other useful formation properties (such as formation water saturation) can be determined based on the formation water salinity.

Abstract: An interpolated position of an incremental encoder is provided. A first signal and a second signal having a quadrature relationship are received from the incremental encoder. A coarse position of the incremental encoder at a first time is produced using the quadrature relationship between the first signal and the second signal. An arcsine or arccosine value based on the first signal at the first time is determined using a lookup table and a fine position of the incremental encoder is calculated using the determined value. The interpolated position of the incremental encoder, based on both the coarse position and the fine position, is then provided.

Abstract: A method for generating a closed flux magnetization pattern of a predetermined rotational direction in a magnetic reference layer of a magnetic layer stack is provided. The method includes applying an external magnetic field in a predetermined direction to the magnetic layer stack causing magnetic saturation of the magnetic reference layer and of a pinned layer of the magnetic layer stack; and reducing the external magnetic field to form a first closed flux magnetization pattern in the magnetic reference layer and a second closed flux magnetization pattern in the pinned layer.

Abstract: A measuring device is provided for measuring an advancement of a cable of a sewer cleaning and/or sewer inspection system. A rotatably mounted magnet is designed such that the advancement of the cable can cause rotations of the at least one rotatably mounted magnet, wherein the magnet follows a movement of the cable in the radial direction during advancement of the cable. A corresponding method is also provided.

Abstract: A method for making calibrated directional electromagnetic logging measurements includes causing an electromagnetic logging tool to make a plurality of voltage measurements while deployed in a subterranean wellbore. A ratio of currents in first and second electromagnetic transmitters is computed and a ratio of gains in first and second electromagnetic receivers is computed. A ratio of selected ones of the measured voltages is processed in combination with the ratio of currents, the ratio of gains, and a test loop calibration coefficient to compute the calibrated directional electromagnetic logging measurement.

Abstract: A radiation hardened current sensor to sense direct current (DC), low frequency alternating current (AC), and high frequency AC includes a DC current transformer (DCCT) including a primary DCCT winding and a secondary DCCT winding. A self-oscillating modulator is coupled to the secondary DCCT winding of the DCCT to maintain a magnetic flux density of the DCCT at an upper limit and a lower limit of a magnetic hysteresis characteristic of the DCCT. An active filter passes only the DC and the low frequency AC from the DCCT as an output. An AC current transformer (ACCT) including a primary ACCT winding and a secondary ACCT winding. The output of the active filter is coupled to the ACCT and the secondary ACCT winding provides the high frequency AC.

Abstract: Methods and systems are provided that employ a combination of dielectric dispersion measurement(s) and Nuclear Magnetic Resonance (NMR) measurement(s) to determine data that characterizes tortuosity of rock and data that characterizes tortuosity of fluid phases in the rock independently from one another.

Abstract: A magnetic susceptibility and conductivity tool (10) which incorporates a transmitter coil (4) energized with a time-varying current from a transmitter coil drive (13). The transmitter coil drive receives a clock signal and induces a data signal (99) including a primary mutual coupling signal and a formation coupling signal. A receiver coil (1) outputs a receiver coil voltage induced by the data signal. A transmitter coil current sense circuit (15) receives current from the transmitter coil and outputs a digital coil current voltage signal. A synthetic null circuit (14) receives the digital current voltage signal and multiplies the digital current voltage signal with a predetermined constant (28) for amplitude of a base primary mutual coupling signal and shifts phase with a predetermined phase offset (27) to output a synthetic null signal (104).

Abstract: A resistivity imaging device and a method of operating the resistivity imaging device in a wellbore. The resistivity imaging device includes a first electrode, a second electrode, and a circuit electrically coupled to the first electrode and the second electrode. An impedance is measured of a formation surrounding the wellbore. Based on the impedance, the circuit is configured into one of a first circuit configuration for operating the resistivity imaging device in a first mode and a second circuit configuration for operating the resistivity imaging device in a second mode. The resistivity imaging device is operated using the circuit in the one of the first circuit configuration and the second circuit configuration.

Abstract: A preamplifier arrangement for an MRI system includes a preamplifier coupled to a loop of a multi-channel coil array of the MRI system, wherein the preamplifier and the loop are subject to potentially form an unstable system with oscillation at one or more peak frequencies. The preamplifier arrangement also includes an impedance matching network disposed between and coupled to the preamplifier and the loop. The impedance matching network is configured to generate a high blocking impedance. The preamplifier arrangement further includes an input network disposed between and coupled to the preamplifier and the loop. The input network is configured to provide an input to suppress gain at the one or more peak frequencies.

Abstract: A method for non-contact current measurement is described. According to one exemplary embodiment, the method comprises the alternating magnetizing of a magnetic core to a maximum value in the positive and negative directions by controlling at least one secondary conductor which is magnetically coupled to the magnetic core; generating an oscillator signal which alternates between a first state and a second state, whereby the alternating magnetization processes are indicated; and determining a first measured value for an effective primary current which flows through at least one primary conductor which is magnetically coupled to the magnetic core, based on the times that the oscillator signal dwells in the first and the second state.

Abstract: The present disclosure is directed to a position detection sensor of an electromagnetic induction type connected to a position detection circuitry. The position detection sensor includes a circular substrate, a plurality of first loop coils arranged in a first direction on the circular substrate, and a plurality of second loop coils arranged in a second direction on the circular substrate, the second direction intersecting the first direction. Each of the plurality of first loop coils includes a straight portion extending in the second direction and a circumferential portion disposed along an outer edge of the circular substrate, and each of the plurality of second loop coils includes a straight portion extending in the first direction and a circumferential portion disposed along the outer edge of the circular substrate.

Abstract: The disclosure extends to systems and devices for determining and maintaining a consistent ground and ground saturation resistance that include a device that includes a grip element and bioelectrical grounding segments, which may be disposed about the grip element on the grounding device.

Abstract: A pulsed magnetic particle imaging system includes a magnetic field generating system that includes at least one magnet, the magnetic field generating system providing a spatially structured magnetic field within an observation region of the magnetic particle imaging system such that the spatially structured magnetic field will have a field-free region (FFR) for an object under observation having a magnetic nanoparticle tracer distribution therein. The pulsed magnetic particle imaging system also includes a pulsed excitation system arranged proximate the observation region, the pulsed excitation system includes an electromagnet and a pulse sequence generator electrically connected to the electromagnet to provide an excitation waveform to the electromagnet, wherein the electromagnet when provided with the excitation waveform generates an excitation magnetic field within the observation region to induce an excitation signal therefrom by at least one of shifting a location or condition of the FFR.