A central idea of techniques herein is that by means of modulation or variation of the supply signal of a Hall sensor, the useful signal portion in the resulting sensor output signal can be separated from the offset portion during operation of the Hall sensor, with no previous calibration or previous serial tests. That course of the sensor output signal resulting from the modulation or variation of the supply signal can then be evaluated or decomposed relative to the components which can be attributed to the offset portion and the useful signal portion. Thus, the offset portion in the sensor output signal can be determined with no (or a negligibly small) external magnetic field applied or with an external magnetic field applied, in case the external magnetic field is constant within a tolerance range while determining the offset portion.

A system and method for acquiring a calibrated eddy-current field model in magnetic resonance imaging (MM) are provided. The method may include one or more of the following operations. An eddy-current field model may be obtained. The eddy-current field model may be transformed by Laplace Transformation. Data of an eddy-current field may be obtained. The data of the eddy-current field may be processed. A calibrated eddy-current field model may be acquired. In addition, the calibrated eddy-current field model may be used to compensate an eddy-current field.

Multiple magnetic field sensors are arranged around a current-containing volume at multiple longitudinal and circumferential positions. Each sensor measures multiple magnetic field components and is characterized by one or more calibration parameters. A longitudinal primary current flows through two end-to-end electrical conductors that are separated by an arc gap, and flows as at least one longitudinal primary electric arc that spans the arc gap and that moves transversely within the arc gap. Estimated transverse position of the primary electric arc is calculated, based on the longitudinal position of the arc gap, and two or more of the measured magnetic field components along with one or more corresponding sensor positions or calibration parameters. In addition, estimated occurrence, position, and magnitude of a transverse secondary current (i.e., a side arc) can be calculated based on those quantities.

A sensing element is provided including a magnetic sensor that detects a first magnetic field component, at least one AC-magnetic field generator that applies at least one additional magnetic field component at a given frequency to the magnetic sensor, where the first magnetic field component and the at least one additional magnetic field component are orthogonal to each other, and at least one demodulator using the given frequency to determine a sensitivity of the sensing element respective to the at least one additional magnetic field component. Also, several methods of operating such sensing element are provided.

A system and method for acquiring a calibrated eddy-current field model in magnetic resonance imaging (MM) are provided. The method may include one or more of the following operations. An eddy-current field model may be obtained. The eddy-current field model may be transformed by Laplace Transformation. Data of an eddy-current field may be obtained. The data of the eddy-current field may be processed. A calibrated eddy-current field model may be acquired. In addition, the calibrated eddy-current field model may be used to compensate an eddy-current field.

Rapid calculation of magnetostriction effects can consist of calculating a stress field and a magnetic field in a structure by determining a magnetic field on the magnetic mesh, determining a magnetostriction from the magnetic field, applying the magnetostriction to the mechanical mesh, determining a stress field on the mechanical mesh, determining an inverse magnetostriction from the stress field, applying the inverse magnetostriction to the magnetic mesh, and determining a new magnetic field on the magnetic mesh by accounting for the inverse magnetostriction. Calculations can be based on data representing a structure, including a magnetic mesh, a mechanical mesh, and a plurality of material properties. After calculation is completed, data characterizing the calculated stress field and magnetic field for the structure can be provided as output. Related apparatus, systems, techniques, methods and articles are also described.

Multiple magnetic field sensors are arranged around a current-containing volume at multiple longitudinal and circumferential positions. Each sensor measures multiple magnetic field components and is characterized by one or more calibration parameters. A longitudinal primary current flows through two end-to-end electrical conductors that are separated by an arc gap, and flows as at least one longitudinal primary electric arc that spans the arc gap and that moves transversely within the arc gap. Estimated transverse position of the primary electric arc is calculated, based on the longitudinal position of the arc gap, and two or more of the measured magnetic field components along with one or more corresponding sensor positions or calibration parameters. In addition, estimated occurrence, position, and magnitude of a transverse secondary current (i.e., a side arc) can be calculated based on those quantities.

Methods and apparatus for characterizing composite materials for manufacturing quality assurance (QA), periodic inspection during the useful life, or for forensic analysis/material testing. System are provided that relate eddy-current sensor responses to the fiber layup of a composite structure, the presence of impact damage on a composite structure with or without a metal liner, volumetric stress within the composite, fiber tow density, and other NDE inspection requirements. Also provided are systems that determine electromagnetic material properties and material dimensions of composite materials from capacitive sensor inspection measurements. These properties are related to the presence of buried defects in non-conductive composite materials, moisture ingress, aging of the material due to service or environmental/thermal exposure, or changes in manufacturing quality.

A system and method for acquiring a calibrated eddy-current field model in magnetic resonance imaging (MRI) are provided. The method may include one or more of the following operations. An eddy-current field model may be obtained. The eddy-current field model may transformed by Laplace Transformation. Data of an eddy-current field may be obtained. The data of the eddy-current field may be processed. A calibrated eddy-current field model may be acquired. In addition, the calibrated eddy-current field model may be used to compensate an eddy-current field.

The invention relates to a method for determining the component of a magnetic field in a predetermined direction. The method comprises preparing a quantum system in a coherent superposition state (S1), letting the quantum system evolve for a delay time period (S2) and performing a readout operation and a projective measurement on the quantum system (S3). The steps (S1, S2, S3) are iteratively repeated in an iteration loop, wherein the delay time period increases linearly by the same time increment after each iteration. The method further comprises determining the component of the magnetic field in the predetermined direction according to the outcome of the projective measurements (S4).