Abstract: A screw pair including inner walls of screw holes in a working nut and a pre-tightening nut with sensor groups including a plurality of displacement sensors capable of measuring a value of a gap between an inner and outer wall of a screw in a diameter direction of the screw hole, the group includes four displacement sensors evenly distributed in a circumferential direction of the screw hole, every two displacement sensors are paired and symmetrical about a center axis, and projections of a plurality of sensor groups in an axial direction overlap the screw; and an adaptive excitation coil is mounted to each displacement sensor, which is capable of attracting the screw in a measurement direction of the adaptive displacement sensor, and a magnetic force of the coil attached is adjustable to change the value of the gap, so that axes of the screw, working nut, and pre-tightening nut coincide.

Abstract: The present disclosure discloses a shear-type vibration-ultrasonic composite sensor and a measuring device. In the shear-type vibration-ultrasonic composite sensor, a metal matching layer includes an insulating layer arranged on a lower surface and a supporting pillar arranged on an upper surface, the metal matching layer is in contact with a to-be-detected object via the insulating layer, a first negative electrode face of a first normal piezoelectric element is attached to one side of the metal matching layer, a first positive electrode face of the first normal piezoelectric element is attached to a second positive electrode face of a second normal piezoelectric element, a second negative electrode face is attached to a first surface of a backing block, and a second surface of the backing block is provided with a metal housing.

Abstract: The present disclosure discloses a shear-type vibration-ultrasonic composite sensor and a measuring device. In the shear-type vibration-ultrasonic composite sensor, a metal matching layer includes an insulating layer arranged on a lower surface and a supporting pillar arranged on an upper surface, the metal matching layer is in contact with a to-be-detected object via the insulating layer, a first negative electrode face of a first normal piezoelectric element is attached to one side of the metal matching layer, a first positive electrode face of the first normal piezoelectric element is attached to a second positive electrode face of a second normal piezoelectric element, a second negative electrode face is attached to a first surface of a backing block, and a second surface of the backing block is provided with a metal housing.

Abstract: The present invention relates to a method and system for correcting acquisition channel of merging unit in power system which belong to the technical field of simulation data collection of power system. The present invention performs data acquisition of each channel firstly, and the acquired data is continuous and effective frequency data, then the collected data is stored to their respective backup areas, and the data storage is stopped until the amount of stored data is up to a predetermined value required for correcting, the data is corrected finally within the respective backup areas of each channel which stops the data storage. The correction process is performed by using corresponding correction module. The method for the channel correction improves the efficiency of channel correction greatly, reduces the correction error, improves the correction precision, and has more simple and convenient operation in comparison to the conventional method for channel correction by modifying hardware parameters.