Abstract: Provided are an alternating current field based defect identification method and an array detection probe. The evaluation method includes the following steps: obtaining a magnetic field Bx signal in direction X and a magnetic field Bz signal in direction Z; removing a background magnetic field of each of the magnetic field Bx signal in the direction X and the magnetic field Bz signal in the direction Z, and obtaining a magnetic field Bx1 signal in the direction X and a magnetic field Bz1 signal in the direction Z without background magnetic fields; drawing an array image of the Bx1 signal and an array image of the Bz1 signal; and locating a distortion zone corresponding to disturbance at the same time and position in the array image of the Bx1 signal and the array image of the Bz1 signal.

Abstract: The present disclosure discloses a visual monitoring system of crack propagation of an underwater structure based on an alternating current field, and an alternating current field crack visual monitoring and evaluation method.

Abstract: A large to medium-size sweeping and mopping vehicle and a mopping vehicle are provided. The large to medium-size sweeping and mopping vehicle includes a vehicle body, and a disc-type sweeping mechanism, a round-roller-type sweeping mechanism and a first mopping mechanism sequentially disposed along the vehicle body; the disc-type sweeping mechanism including a clean water tank and disc-type sweeping edge brushes driven by a motor and disposed obliquely with respect to ground, the clean water tank being disposed in front of the vehicle body driver zone, and a nozzle being disposed above each disc-type sweeping edge brush and in communication with the clean water tank; the round-roller-type sweeping mechanism including a refuse collector and a round-roller-type main sweeping brush driven by the motor to rotate horizontally; and the first mopping mechanism including a dragging roller, a guiding mopping roller, a guiding roller, a ring-shaped mop and a washing water tank.

Abstract: A large to medium-size sweeping and mopping vehicle and a mopping vehicle are provided. The large to medium-size sweeping and mopping vehicle comprises a vehicle body, and a disc-type sweeping mechanism, a round-roller-type sweeping mechanism and a first mopping mechanism sequentially disposed along the vehicle body; the disc-type sweeping mechanism comprising a clean water tank and disc-type sweeping edge brushes driven by a motor and disposed obliquely with respect to ground, the clean water tank being disposed in front of the vehicle body driver zone, and a nozzle being disposed above each disc-type sweeping edge brush and in communication with the clean water tank; the round-roller-type sweeping mechanism comprising a refuse collector and a round-roller-type main sweeping brush driven by the motor to rotate horizontally; and the first mopping mechanism comprising a dragging roller, a guiding mopping roller, a guiding roller, a ring-shaped mop and a washing water tank.