Abstract: A tent cover system for providing improved ventilation and cooling is disclosed. The tent cover system includes a frame having a hub and a plurality of roof poles extending therefrom; a cover having a reflective topside and a blackout underside; a plurality of vertical poles configured to hoist the cover above a tent, thereby creating an airspace therebetween; and a plurality of guy lines configured to removably secure the cover to a ground surface.

Abstract: A circular layer of piezoelectric material is supported on a larger substrate disc of a thin somewhat flexible material. Flexing of the disc generates an electrical signal. The substrate disc is weighted at its periphery, and the central portion of the disc is supported on a member for transferring motion or vibration that it is desired to detect. In the preferred embodiment the center support is provided by a pair of bosses projecting into the otherwise hollow interior of a two-part casing that encloses the disc-weight assembly. The weights impart a peripheral inertia that makes the composite unit sensitive to minute vibrations.