The present disclosure relates to a technical virtual sensing idea of indirectly measuring structural vibration information on an unmeasured point while minimizing the number of sensors attached for actual measurement, and more particularly, to a technique of estimating measurement data of an unmeasured point using a finite element model, synchronized and updated based on experimental data of an actual measurement subject structure, and a virtual sensing algorithm.

A determination apparatus includes circuitry to receive a detection result of a time-varying physical quantity generated by rotation of a rotator attached to a rotation shaft, and rotation angle information of the rotator; and determine a rotation state of the rotator based on the detection result and the rotation angle information.

A determination apparatus includes circuitry to receive a detection result of a time-varying physical quantity generated by rotation of a rotator attached to a rotation shaft, and rotation angle information of the rotator; and determine a rotation state of the rotator based on the detection result and the rotation angle information.

A sensor system includes a sensor network comprising at least one optical fiber having one or more optical sensors. At least one of the optical sensors is arranged to sense vibration of an electrical device and to produce a time variation in light output in response to the vibration. A detector generates an electrical time domain signal in response to the time variation in light output. An analyzer acquires a snapshot frequency component signal which comprises one or more time varying signals of frequency components of the time domain signal over a data acquisition time period. The analyzer detects a condition of the electrical device based on the snapshot frequency component signal.

A sensor system includes a sensor network comprising at least one optical fiber having one or more optical sensors. At least one of the optical sensors is arranged to sense vibration of an electrical device and to produce a time variation in light output in response to the vibration. A detector generates an electrical time domain signal in response to the time variation in light output. An analyzer acquires a snapshot frequency component signal which comprises one or more time varying signals of frequency components of the time domain signal over a data acquisition time period. The analyzer detects a condition of the electrical device based on the snapshot frequency component signal.

Drill bit vibration data for lateral, axial, and torsional directions of a drill bit is collected for a simulated or deployed drill bit for visualization of 3D coupled vibration. A frequency converter transforms the drill bit vibration data into frequency vibration data. A drill bit analyzer identifies local maxima (“peaks”) in the frequency vibration data in each of the lateral, axial, and torsional directions. Common peaks across all 3 directions with sufficiently high frequency and sufficiently high bit rotation speed are indicated as 3D coupled vibration. A drill bit data visualizer uses the indications of 3D coupled vibration in addition to the vibration data and frequency vibration data to generate visualizations of 3D coupled vibration in the drill bit.

Drill bit vibration data for lateral, axial, and torsional directions of a drill bit is collected for a simulated or deployed drill bit for visualization of 3D coupled vibration. A frequency converter transforms the drill bit vibration data into frequency vibration data. A drill bit analyzer identifies local maxima (“peaks”) in the frequency vibration data in each of the lateral, axial, and torsional directions. Common peaks across all 3 directions with sufficiently high frequency and sufficiently high bit rotation speed are indicated as 3D coupled vibration. A drill bit data visualizer uses the indications of 3D coupled vibration in addition to the vibration data and frequency vibration data to generate visualizations of 3D coupled vibration in the drill bit.

A looseness detection structure configured to detect looseness between a bolt and a nut that fix two components including a conductive film configured to be attached on a surface of the component, the surface of the component including a hole into which the bolt is inserted, the conductive film being attached such that the conductive film is not directly conductive to the component, a part of the conductive film having a dimension relating to a half wavelength of a high-frequency signal propagating inside the components, and a non-conductive film between a surface of the component and the conductive film in a case where surfaces of the components are conductors, and a second conductive film on a surface of the component in a case where the surfaces of the components are insulators, the second conductive film being opposite to the conductive film.

In an electronic nose apparatus and method based on spectrum analysis, 1) a gaseous sample is dissolved into a solvent in an impinger, and the sample dissolved into the solvent is introduced into an RF resonator, and 2) RF having various absorption spectra according to materials are generated in the RF resonator, and the type of gas is determined through spectrum analysis so that an electronic nose is implemented. In this way, it is possible to overcome the resolution of gas chromatography (GC) and a sensor array and a limited number of multi-channel sensors (the number of channels).

In an electronic nose apparatus and method based on spectrum analysis, 1) a gaseous sample is dissolved into a solvent in an impinger, and the sample dissolved into the solvent is introduced into an RF resonator, and 2) RF having various absorption spectra according to materials are generated in the RF resonator, and the type of gas is determined through spectrum analysis so that an electronic nose is implemented. In this way, it is possible to overcome the resolution of gas chromatography (GC) and a sensor array and a limited number of multi-channel sensors (the number of channels).