Abstract: A gradiometer includes a at least one magnet attached to a beam. The magnet moves in response to a magnetic force. A sensing element is configured to measure movement or deflection of the beam or magnet. The gradiometer is configured to determine a gradient of a magnetic field acting on the first magnet based on movement of the magnet. The gradiometer can further measure higher order gradients.

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: A method of determining a gradient of a magnetic field, includes the steps of: biasing a first/second magnetic sensor with a first/second biasing signal; measuring and amplifying a first/second magnetic sensor signal; measuring a temperature and/or a stress difference; adjusting at least one of: the second biasing signal, the second amplifier gain, the amplified and digitized second sensor value using a predefined function f(T) or f(T, ??) or f(??) of the measured temperature and/or the measured differential stress before determining a difference between the first/second signal/value derived from the first/second sensor signal. A magnetic sensor device is configured for performing this method, as well as a current sensor device, and a position sensor device.

Abstract: A rotation rate sensor, including at least: one oscillating mass, deflectable in a drive direction and in a detection direction oriented perpendicularly to the drive direction; one drive circuit for prompting a defined oscillatory movement of the oscillating mass in the drive direction; one circuit for detecting a measuring signal, which corresponds to the deflection of the oscillating mass in the detection direction; and one read-out circuit for reading out and pre-processing the measuring signal. The read-out circuit includes a demodulator, with which a useful signal and a quadrature signal are extractable from the measuring signal. The read-out circuit includes a sigma-delta A/D converter. An offset voltage is feedable to the sigma-delta A/D converter, which is selected in such a way that tonal artifacts in the frequency spectrum of the digitized useful signal are shifted into a frequency range outside of the bandwidths of the useful signal to be expected.

Abstract: Imaging methods for assessing the macromolecular content, such as myelin, are of great interest for understanding brain tissue microstructure, and have shown potentials in diagnosing and prognosing demyelinating diseases. for example. Magnetization transfer (MT) is a MRI contrast mechanism that enables detection of macromolecules. Previously, the MT effect has been analyzed by a semi-quantitative method termed magnetization transfer ratio (MTR) or by a quantitative magnetization transfer (qMT) method. However, because MTR does not have enough sensitivity and specificity to myelin, and qMT takes a very long scan time, their translation into clinical scenarios has been limited. This disclosure describes a MT data analysis metric using double saturation pulse offsets and powers (dopMTR).

Abstract: The present disclosure is directed to techniques for synchronizing a rotational eccentric mass of a gravitational transducer used for a magnetic resonance elastography acquisition with a corresponding magnetic resonance elastography scan carried out by a magnetic resonance imaging system, wherein the rotation of the eccentric mass is driven by a shaft. The method includes starting the rotation of the eccentric mass at a set vibration frequency and the magnetic resonance elastography scan at a set acquisition frequency; determining the rotational position of the shaft; defining the rotational position as first reference position; calculating further reference positions. At the start time of each subsequent acquisition period, determining the current rotational position of the shaft; comparing the determined current rotational position with the theoretically expected reference position and decreasing or increasing the rotational speed of the rotational eccentric mass based on the comparison.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for closed-loop control of a system using one or more electron paramagnetic resonance (EPR) sensors located on-site. With such EPR sensors, a change can be applied to the system, the EPR sensors can measure the effect(s) of the change, and then adjustments can be made in real-time. This feedback process may be repeated continuously to control the system.

Abstract: A transducer for measuring the thickness of ice in a body of water includes a transducer body, at least one ice presence sensor for measuring the presence of ice at a point beyond a boundary layer between the transducer body and the body of water, a flotation element, a controller, and a display assembly. The transducer body includes waterproof membrane sealed orifices positioned on the transducer body for one or more ice presence sensors. A tether point attaches an anchor to keep the transducer at a fixed location in the water body. The ice presence sensor includes a sense probe passing through the waterproof membrane, a sense probe seal, a drive rod, a switch, and an actuator. The display includes one or more visible elements to indicate ice thickness at the transducer location. The ice thickness is inferred by the collective indications at the one or more ice presence sensors.

Abstract: The inventive concepts provide a magnetic property measurement apparatus capable of quickly measuring a magnetic property of a subject without a decrease in a measurement speed that might occur due to an electromagnet. In addition, the inventive concepts provide a magnetic property measurement apparatus capable of monitoring a magnetization distribution of a memory device as an image and integrating images by using a TDI camera, thereby being capable of performing highly sensitive measurement and not having to capture images for a long time. The magnetic property measurement apparatus includes: a magnetic field generation unit configured to generate a magnetic field which is constant with time and varies with relative position; a mobile unit configured to move a subject to be measured in the magnetic field; and a measurement unit configured to measure a magnetic property of the subject moving in the magnetic field.

Abstract: The present disclosure provides techniques for using opto-isolator circuitry to control switching circuitry configured to be coupled to a radio-frequency (RF) coil of a magnetic resonance imaging (MRI) system. In some embodiments, opto-isolator circuitry described herein may be configured to galvanically isolate switch controllers of the MRI system from the switching circuitry and/or provide feedback across an isolation barrier. Some embodiments provide an apparatus including switching circuitry configured to be coupled to an RF coil of an MRI system and a drive circuit that includes opto-isolator circuitry configured to control the switching circuitry. Some embodiments provide an MRI system that includes an RF coil configured to, when operated, transmit and/or receive RF signals to and/or from a field of view of the MRI system, switching circuitry coupled to the RF coil, and a drive circuit that includes opto-isolator circuitry configured to control the switching circuitry.

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: A magnetic resonance imaging apparatus includes a T/R switch. The T/R switch includes a double sided microstripline based hybrid couplers with a top side and a bottom side each including two concentric microstripline based hybrid couplers. Each of the two concentric microstripline based hybrid couplers includes an inner microstripline based hybrid coupler and an outer microstripline based hybrid coupler. The inner microstripline based hybrid coupler forms an inner loop of the two concentric microstripline based hybrid couplers and the outer microstripline based hybrid coupler forms an outer loop. In a transmission mode, the inner microstripline based hybrid coupler and the outer microstripline based hybrid coupler at the top side of the dual-tuned T/R switch are activated. In a receiving mode the inner microstripline based hybrid coupler and the outer microstripline based hybrid coupler at the top side and at the bottom side of the dual-tuned T/R switch are activated.

Abstract: A method for recording a magnetic resonance image dataset includes providing a magnetic resonance sequence with a series of sequence blocks, and providing at least one correction term to compensate for a magnetic field change. The magnetic field change is produced as a change of an actual magnetic field compared to a setpoint magnetic field by gradient pulses. The magnetic field change is established via a transfer characteristic of the gradient system of the magnetic resonance installation. The at least one correction term is used to compensate for the magnetic field change, and at least one magnetic resonance image dataset is recorded with the magnetic resonance sequence using the correction term.

Abstract: In the present disclosure, there is provided a permeability measurement jig including a first waveguide, wherein a signal line of the first waveguide comprises an excited magnetic part at one end side, and a magnetic field is generated at the excited magnetic part by an excitation signal, and a second waveguide, wherein a signal line of the second waveguide comprises a detection part at one end side, a detection signal is induced at the detection part due to an action of the magnetic field generated at the excited magnetic part to a measurement sample, and the detection part is placed on the excited magnetic part to face the excited magnetic part at a predetermined distance. A permeability measurement device having the permeability measurement jig and a permeability measurement method are disclosed.

Abstract: An atomic magnetometer, which operates in a communication system using a magnetic signal in a very low frequency (VLF) band, may comprise: a vapor cell comprising one or more alkaline metal atoms; a pump light source configured to provide circularly polarized pump beams to the vapor cell; an irradiation light source configured to provide linearly polarized irradiation beams to the vapor cell; a magnetic signal detecting unit configured to detect a magnetic signal by measuring a polarization rotation angle from the linearly polarized irradiation beam passing through the vapor cell; and a bias magnetic field control unit configured to control a bias magnetic field applied to the vapor cell.

Abstract: An imaging apparatus has an MRT system with an MR receiving antenna configured to receive a first receive signal containing an MR signal from an object to be examined during an examination period. The imaging apparatus includes a modality for examining the object and/or for acting on the object via mechanical or electromagnetic waves, wherein the modality has an electronic circuit. The imaging apparatus includes an auxiliary antenna arranged and configured to receive a second receive signal containing an interference signal generated by the electronic circuit during the examination period. The imaging apparatus has a processing system configured to suppress interference in the first receive signal based on the first and the second receive signal.

Abstract: According to one embodiment, a magnetic resonance imaging system includes a first imaging apparatus, a first cooling system, a second imaging apparatus, a second cooling system and a cooling control device. The first imaging apparatus includes a first magnet configured to generate a static magnetic field. The first cooling system is configured to cool the first magnet. The second imaging apparatus includes a second magnet configured to generate a static magnetic field. The second cooling system is configured to cool the second magnet. The cooling control device is configured to switch a cooling target of each of the first cooling system and the second cooling system.

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: Sensitivity of a magnetic sensor using the magnetic impedance effect is improved. A magnetic sensor includes: a non-magnetic substrate; a sensitive element provided on the substrate, including a soft magnetic material, having a longitudinal direction and a short direction, provided with uniaxial magnetic anisotropy in a direction intersecting the longitudinal direction, and sensing a magnetic field by a magnetic impedance effect; and a protrusion part including a soft magnetic material and protruding from an end portion in the longitudinal direction of the sensitive element.

Abstract: A magnetic field detector for detecting magnetic fields over a broad operational temperature range comprising: a plurality of Josephson junctions connected to each other by superconducting interconnecting paths, wherein the plurality of Josephson junctions are arranged in an array; and wherein the superconducting interconnecting paths connecting the plurality of Josephson junctions in the array are designed to not all have a uniform cross-sectional geometry with respect to each other.