Abstract: A magnetic sensor device includes a first chip including a first magnetic sensor, a second chip including a second magnetic sensor and a third magnetic sensor, and a support having a reference plane. The first magnetic sensor includes at least one first magnetic detection element, and detects a first component of an external magnetic field. The second magnetic sensor includes at least one second magnetic detection element, and detects a second component of the external magnetic field. The third magnetic sensor includes at least one third magnetic detection element, and detects a third component of the external magnetic field. The first chip and the second chip are mounted on the reference plane.

Abstract: Systems and methods for monitoring a filter in, for example, an immersion cooled system are described. In one embodiment the application pertains to a process comprising employing a filter media to filter fluid wherein one or more electrical properties change depending upon pH of the filter fluid. The one or more electrical properties may be measured to monitor the filter. If desired, the filter media's electrical properties may be modified based on the configuration of the filter to facilitate the measurements.

Abstract: A tension measuring method installs a reel having a cylindrical coil forming part on a cable to be measured, forms a coil by winding a conductor around the coil forming part, measures a magnetic hysteresis loop of the cable by supplying a current to the coil to generate a magnetic field, and computes a tension of the cable using a parameter determined from the hysteresis loop. A magnetic field sensor and a magnetic flux sensor are provided inside a through hole in the coil forming part, and the cable is positioned inside the through hole. The magnetic field is varied so that the hysteresis loop includes a near-saturation magnetization region, to measure the hysteresis loop using the sensors. The parameter is selected from a magnetic flux or a magnetic flux density, a remanent magnetization, a coercivity, a magnetic permeability, and a hysteresis loss in the near-saturation magnetization region.

Abstract: A system for tracking a below-ground transmitter from an aerial receiver. The receiver has an antenna assembly, a processor, and a propulsion system. The antenna assembly detects the magnetic field from an underground transmitter and generates an antenna signal. The processor is programmed to receive the antenna signal and generate a command signal, which moves the receiver to a position above the transmitter. Once in the desired position, which may be a reference plane at a fixed elevation, the antenna assembly measures the magnetic field to determine the location of the drill bit along borepath.

Abstract: An apparatus for producing magnetic field gradients includes (a) a first planar electromagnet coil set configured to produce a first magnetic field gradient with respect to a first axis, (b) a second planar electromagnet coil set configured to produce a second magnetic field gradient with respect to a second axis that is orthogonal to the first axis, (c) a third planar electromagnet coil set configured to produce a third magnetic field gradient with respect to a third axis that is orthogonal to the first and second axes, and (d) a controller configured to selectively provide power to the first, second, and/or third electromagnet coil sets to sequentially produce a localization magnetic field gradient with respect to each of the first, second, and third axes, at least a portion of each localization magnetic field gradient having a monotonically-varying magnetic field magnitude along a respective axis.

Abstract: Disclosed is a multi-channel atomic magnetic detector (100), including at least one detection assembly, with each detection assembly including a plurality of detection air chambers (130) in the same plane and a light-splitting member (110) for allocating polarized beams from a light source (180) to each detection air chamber (130) in the detection assembly, wherein the plurality of detection air chambers (130) of each detection assembly are arranged in a centrally symmetric manner or an axially symmetric manner relative to the light-splitting member (110). The multi-channel atomic magnetic detector (100) has a high detection density and is beneficial for noise reduction.

Abstract: A magnetic field measuring apparatus includes a digital FLL circuit. The digital FLL circuit includes a first amplifier configured to amplify voltage output by a superconducting quantum interference device in accordance with strength of a magnetic field strength, an AD converter configured to, convert analog signals to first digital values, an integrator configured to integrate the first digital values output by the AD converter, a DA converter configured to receive an integral value output by the integrator as a second digital value, convert the second digital value to voltage, and output the converted voltage, a signal switcher configured to connect an output of the first amplifier or an output of the DA converter to an input of the AD converter, and a storage unit configured to store a correction value that corrects the integral value received by the DA converter.

Abstract: A sensor integrated circuit including a regulator for generating a regulated voltage includes a digital load configured to draw a load current from the regulator in response to a clock signal during in situ operation and a comparator configured to determine the absence or presence of a fault during in situ operation. The load current is less than or equal to a predetermined level in the absence of a fault and is greater than the predetermined level in the presence of a fault. The comparator is responsive to the load current and to a threshold level and is configured to generate a comparator output signal having a level indicative of whether the load current is less than or greater than the threshold level in order to thereby determine the absence or presence of a fault during in situ operation, respectively.

Abstract: A speed detection device includes a comparator module, a sensor lead with a node connected to the comparator module, and a limit set module. The limit set module is connected to the sensor lead node and to the comparator by an upper limit lead and a lower limit lead to provide upper and lower limits to the comparator that vary according to amplitude variation in voltage applied to the sensor lead.

Abstract: A device for sensing a magnetic field, comprising a closed superconducting loop configured to collect a magnetic field to be sensed, hereinafter external magnetic field, the closed superconducting loop having a path width (wp) and being provided with a constriction having a width (wc) narrower than the path width, the constriction generating a non-uniform magnetic field, hereinafter internal magnetic field, in response to the external magnetic field, a vibrating mechanical oscillator coupled to, or formed by the constriction and responsive to the internal magnetic field, and a detector configured to detect deflection or vibration of the mechanical oscillator and providing a signal indicative of the deflection or vibration.

Abstract: Multi-dimensional spectra associated with a specimen are reconstructed using lower dimensional spectra as constraints. For example, a two-dimensional spectrum associated with diffusivity and spin-lattice relaxation time is obtained using one-dimensional spectra associated with diffusivity and spin-lattice relaxation time, respectively, as constraints. Data for a full two dimensional spectrum are not acquired, leading to significantly reduced data acquisition times.

Abstract: Systems and methods for providing a visualization capability to map magnetic fields. The system utilizes a high-sensitivity magnetic field sensor (e.g., a magnetometer inside a tube made of magnetic shielding material) disposed on one side of a magnetic field modulation screen to acquire measurement data representing an image of a magnetic field. The magnetic field modulation screen includes a multiplicity of magnetic field-generating pixel elements (e.g., current-carrying loops made of electrically conductive material). Optionally, the system also uses compressive sensing techniques to reduce the amount of measurement data required to reconstruct an image of the original magnetic field. Compressive sensing is enabled by not supplying current to a different selected individual magnetic field-generating pixel element of the magnetic field modulation screen at successive sampling times.

Abstract: A magnetic field generator includes a refrigerating machine, a cold head, a superconductor which is formed in a cylindrical shape, a cold head extension portion which extends from the cold head and is brought into thermal contact with the superconductor at its extended end; and a vacuum heat insulating container having an internal space in which the cold head, the cold head extension portion, and the superconductor are received. The superconductor has a room temperature bore space, which is formed on its inner peripheral side along an axial direction of the superconductor, and is spatially isolated from the internal space of the vacuum heat insulating container. The room temperature bore space has both ends communicating to an outside of the magnetic field generator.

Abstract: An arrangement that enables performing of both magnetic particle imaging and magnetic resonance imaging and a device including the arrangement are provided. The arrangement that enables performance of both magnetic particle imaging and magnetic resonance imaging includes: at least one primary magnetic element pair configured to generate a selection magnetic field (SMF1/SMF2) for magnetic particle imaging, at least one secondary magnetic element pair configured to generate a driving magnetic field, and at least one tertiary magnetic element pair configured to generate a focus magnetic field (FMF).

Abstract: A system for measuring an angular position of a rotor with respect to a stator, wherein the rotor is rotatable around a rotation axis, the system comprising: a magnetic source mounted on the rotor, having at least four magnet poles and providing a periodically repetitive magnetic field pattern with respect to the rotation axis; a sensor mounted on the stator and comprising a plurality of sensor elements for measuring at least one magnetic field component of the magnetic field and for providing a measurement signal thereof; the sensor being located substantially centered around the rotation axis, in a plane substantially perpendicular to the rotation axis at a first distance from the magnetic source; the sensor elements being located substantially on a circle at a second distance from the rotation axis; a calculator that determines the angular position by calculating it from the measurement signals.

Abstract: Disclosed herein are a continuous scanning method using signal shielding and an apparatus for the continuous scanning method. The continuous scanning method includes producing a magnetic field on consecutively input samples by applying a signal to an excitation solenoid coil, blocking signal detection in a partial region so that only one harmonic peak is detected by a detection solenoid coil, which is a differential coil, using a magnetic field produced by at least one magnet, and sequentially detecting one harmonic peak in the samples based on the detection solenoid coil, and performing scanning of nanomagnetic particles on respective samples based on a signal for the detected harmonic peak.

Abstract: A sensor device comprises an electrically conductive chip carrier, wherein the chip carrier comprises an auxiliary structure, wherein the auxiliary structure comprises a first precalibration current terminal and a second precalibration current terminal, a magnetic field sensor chip arranged on a mounting surface of the chip carrier, wherein the magnetic field sensor chip comprises a sensor element, wherein the shape of the auxiliary structure is embodied such that an electrical precalibration current flowing from the first precalibration current terminal to the second precalibration current terminal through the auxiliary structure induces a predefined precalibration magnetic field at the location of the sensor element, wherein during measurement operation of the precalibrated sensor device, no precalibration current flows between the first precalibration current terminal and the second precalibration current terminal.

Abstract: A method for determining pore size distribution of rocks is provided. Capillary pressure measurements on rock cores are analyzed to determine a pore size distribution, with smaller pores requiring greater capillary pressure to relinquish contained fluid. Large pores with rough surfaces introduce inaccuracies in determining the pore size distribution. Embodiments of the invention correct the rough surface induced inaccuracies by measuring the shift in NMR T2 distribution from full saturation to the current state of desaturation and subtracting the T2 contributions in the desaturated state that have smaller T2 values (i.e., smaller transverse relaxation time) than the smallest T2 values (i.e., shortest transverse relaxation time) in the saturated distribution.

Abstract: Measurements of a core sample at scales of measurement that differ by multiple orders of magnitude can be used to calculate a value that fairly represents surface roughness of the core sample. This surface roughness value can be used to determine petrophysical properties of the subsurface formation from which the core sample was obtained. The measurements can be nuclear magnetic resonance (NMR) diffusion-relaxation and gas-adsorption measurements. Surface relaxivities at the different scales are determined from the measurements and a ratio those surface relaxivities can be used to calculate the surface roughness value.

Abstract: According to some aspects, a portable magnetic resonance imaging system is provided, comprising a magnetics system having a plurality of magnetics components configured to produce magnetic fields for performing magnetic resonance imaging. The magnetics system comprises a permanent B0 magnet configured to produce a B0 field for the magnetic resonance imaging system, and a plurality of gradient coils configured to, when operated, generate magnetic fields to provide spatial encoding of emitted magnetic resonance signals, a power system comprising one or more power components configured to provide power to the magnetics system to operate the magnetic resonance imaging system to perform image acquisition, and a base that supports the magnetics system and houses the power system, the base comprising at least one conveyance mechanism allowing the portable magnetic resonance imaging system to be transported to different locations.