The invention provides a foldable box member that can be used to create an enclosure andor box that is configured to hold a set of supports. The roof panel includes at least one sliding panel and non-sliding panels arranged adjacent to the sliding panel in a longitudinal direction of a vehicle roof, and a weather strip is attached to provide a seal between the sliding panel and the non-sliding panels. A repetitive control system applies an external force to the oscillator so as to cancel out the Coriolis force to achieve an angular velocity measuring operation at a high sensitivity and a high SN ratio. The fiber optic element can include two fiber optic elements coupled to the test region. The invention further provides a liquid pressure regulator having a differential diaphragm plate having a rigid structure, having a first side of a first surface area, and an opposed second side of a second surface area, where the first surface area and the second surface area are unequal.