摘要:
A gas pressure sensor comprises a contour piezoelectric vibrator and the pressure of gas is detected by measuring an equivalent series resistance of the vibrator which is surrounded by the gas whose pressure is to be detected.
摘要:
A content usage control system comprises a copyright holder system, content server, license server and user system. The ACL setting section of the copyright holder system sets a license ACL expressed as a structure by a combination of logic sums and logic products of a plurality of partial licenses for the content, based on the user ID and a plurality of physical element IDs including media used in the user system, and stores the license ACL in an access control list. The license server controls the usage of the content by the user utilizing the access control list.