Abstract: A rotation speed detection apparatus includes a main rotor, a main magnetic sensor, an auxiliary rotor, an auxiliary magnetic sensor, and a speed increase portion. The main rotor is driven at a rotation speed proportional to a rotation speed of a wheel mounted to a vehicle. The main magnetic sensor magnetically detects a movement of a main magnetic marker positioned along a circumferential direction in the main rotor. The auxiliary rotor is driven at a peripheral speed higher than a peripheral speed of the main rotor and at a rotation speed proportional to the rotation speed of the wheel. The auxiliary magnetic sensor magnetically detects a movement of an auxiliary magnetic marker positioned along a circumferential direction in the auxiliary rotor. The speed increase portion rotatively drives the auxiliary rotor at the peripheral speed higher than the peripheral speed of the main rotor.

Abstract: A fitted housing includes a first housing and a second housing. The first housing includes a rib projecting from its one surface. The rib includes a flat contact surface on one side surface of the rib, and includes a snap piece that generates elastic force in a direction perpendicular to the contact surface and a movable region that accommodates the snap piece, which is contracted, on the other side surface of the rib. The second housing is fitted to the first housing and includes a rail having an inside distance corresponding to a distance between a vertex of the contracted snap piece and the contact surface. The rib and the snap piece are fitted to the rail. A fitted portion between the first housing and the second housing is welded.

Abstract: A protective structure for an electrical circuit device attached to a vehicle includes a resin case, an electrical circuit, and a rigid body. The electrical circuit is contained in the resin case. The rigid body is contained in the resin case. The rigid body protrudes toward a collision-prone side of the vehicle beyond the resin case. The rigid body deforms or displaces to absorb collision energy when the vehicle is involved in a collision on the collision-prone side.

Abstract: A protective structure for an electrical circuit device attached to a vehicle includes a resin case, an electrical circuit, and a rigid body. The electrical circuit is contained in the resin case. The rigid body is contained in the resin case. The rigid body protrudes toward a collision-prone side of the vehicle beyond the resin case. The rigid body deforms or displaces to absorb collision energy when the vehicle is involved in a collision on the collision-prone side.

Abstract: A method for mutually mapping first three-dimensional data C1 and second three-dimensional shape or a two-dimensional image by specifying a plurality of correspondence points RP, wherein the first three-dimensional data C1 are displayed on a display screen and a contour line TU designating the height in the depth direction is displayed within the first three-dimensional data C1, and the contour line TU is used as a guide marker of the position of the correspondence points RP in the depth direction.