A metal detection apparatus that can accurately and automatically determine whether a metal passing through the inspection area is a magnetic or non-magnetic metal comprises a detection unit quadrature-detecting a differential detection signal of magnetic field fluctuation in the inspection area due to the passage of a workpiece, and a determination unit that determines the presence or absence of a mixed metal based on both fluctuation components after the detection. The determination unit compares sample signal phase data obtained beforehand from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of various metal samples, with the signal phase data obtained from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of the workpiece mixed with metal, and determines the type of metal passing through the inspection area based on the phase determination result.

A metal detection apparatus that can accurately and automatically determine whether a metal passing through the inspection area is a magnetic or non-magnetic metal comprises a detection unit quadrature-detecting a differential detection signal of magnetic field fluctuation in the inspection area due to the passage of a workpiece, and a determination unit that determines the presence or absence of a mixed metal based on both fluctuation components after the detection. The determination unit compares sample signal phase data obtained beforehand from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of various metal samples, with the signal phase data obtained from the detection signal of the magnetic field fluctuation in the inspection area due to the passage of the workpiece mixed with metal, and determines the type of metal passing through the inspection area based on the phase determination result.

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. The pulsed magnetic particle imaging system further includes a detection system arranged proximate the observation region, the detection system being configured to detect the excitation signal to provide a detection signal. The excitation waveform includes a transient portion and a substantially constant portion.

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. The pulsed magnetic particle imaging system further includes a detection system arranged proximate the observation region, the detection system being configured to detect the excitation signal to provide a detection signal. The excitation waveform includes a transient portion and a substantially constant portion.

A magnetic tag sensor includes a cylinder and threaded pipe embedded therein and simulates a magnetic dipole; two threaded pipe wiring interfaces being connected to first and second cables, running through a cylinder upper cross-section outer wall and extending out of the cylinder; the cylinder is sleeved on a guide rail and at a junction between a riverbed and water; an guide rail end inserts into the riverbed, a water sealing box is mounted on a top of the guide rail, a power supply module, a relay and a load arranged inside the water sealing box, the first cable connected to a positive pole of the power supply module, and the second cable connected to a negative pole through the relay and load connected in series; and the threaded pipe in the wall of the cylinder moves up and down with the riverbed to generate a magnetic field signal.

A magnetic tag sensor includes a cylinder and threaded pipe embedded therein and simulates a magnetic dipole; two threaded pipe wiring interfaces being connected to first and second cables, running through a cylinder upper cross-section outer wall and extending out of the cylinder; the cylinder is sleeved on a guide rail and at a junction between a riverbed and water; an guide rail end inserts into the riverbed, a water sealing box is mounted on a top of the guide rail, a power supply module, a relay and a load arranged inside the water sealing box, the first cable connected to a positive pole of the power supply module, and the second cable connected to a negative pole through the relay and load connected in series; and the threaded pipe in the wall of the cylinder moves up and down with the riverbed to generate a magnetic field signal.

A position estimation device acquires detection values of magnetic field strength at three or more locations of a rotor in a range where a rotor angle is less than one rotation. A section is selected based on a detection value of the magnetic field strength from predetermined sections for a pole pair number of the rotor. A feature amount calculator is provided to calculate feature amounts of a waveform of the magnetic field strength based on a combination of the detection values of the magnetic field strength according to the section selected. An estimator is provided to determine, for each segment associated with the section selected, whether or not a magnitude relationship of the feature amounts learned in advance coincides with a magnitude relationship of the feature amounts calculated, and estimating, as a rotation position of the rotor, the pole pair number associated with the segment having the same magnitude relationship.

A position estimation device acquires detection values of magnetic field strength at three or more locations of a rotor in a range where a rotor angle is less than one rotation. A section is selected based on a detection value of the magnetic field strength from predetermined sections for a pole pair number of the rotor. A feature amount calculator is provided to calculate feature amounts of a waveform of the magnetic field strength based on a combination of the detection values of the magnetic field strength according to the section selected. An estimator is provided to determine, for each segment associated with the section selected, whether or not a magnitude relationship of the feature amounts learned in advance coincides with a magnitude relationship of the feature amounts calculated, and estimating, as a rotation position of the rotor, the pole pair number associated with the segment having the same magnitude relationship.

A material defect detection device that detects a material defect in a predetermined region of metallic equipment using a magnetic field distribution in the predetermined region measured by a magnetic sensor array including a plurality of magnetic sensors, the material defect detection device including: a processor that calculates a density distribution of magnetic dipoles in the predetermined region based on the magnetic field distribution and calculates a depth distribution of material defect in the predetermined region based on the density distribution of the magnetic dipoles.

An information processing device, an information processing method, and a recording medium storing an information processing program. The information processing device and the information processing method include obtaining measurement data, accepting a specification of time in the measurement data as a specified time, reducing noise from the measurement data using each one of a plurality of methods, evaluating a result of noise reduction at the specified time, the noise reduction being performed using each one of the plurality of methods, and selecting one of the plurality of methods based on the evaluated result of noise reduction. The recording medium storing the information processing program for causing a computer to execute the information processing method.