Abstract: Provided is a heater including: a substrate that has electrical conductivity; a first insulation portion that is provided on a first surface of the substrate, has an insulation property; at least one heat generation body that is provided on the first insulation portion; a second insulation portion that is provided on a second surface of the substrate which is opposite to the first surface, has an insulation property; at least one detection unit that is provided on at least one of the first insulation portion and the second insulation portion; and a first wiring which is provided on at least one of the first insulation portion and the second insulation portion, and in which one end is electrically connected to one terminal of the detection unit and the other end is electrically connected to the substrate having the electrical conductivity.

Abstract: A method for measuring three-dimensional displacement of a mass comprises the steps of providing a measuring object placed on the end surface of the mass, for reflecting at least a fraction of three-dimensional displacement of the mass, arranging a displacement measuring equipment for free displacement relative to the mass and in opposition to the measuring object, and measuring three-dimensional relative displacement of the mass by detecting relative displacement of sad displacement indicative means relative to the displacement measuring equipment by the latter.

Abstract: A three-dimensional displacement measuring system measures the three-dimensional displacement of a mass such as rock. A first cylindrical member is provided as a displacement indicating device and is arranged on one side of a discontinuous surface, such as a crack, in a bore hole in the rock. The bore hole extends across the discontinuous surface. A second cylindrical member is provided as a displacement measuring device on the other side of the discontinuous surface and is free to displace relative to the mass and the first cylindrical member and is located opposite to the first cylindrical member.