Abstract: The present disclosure relates to a plaster board comprising a first layer of hardened plaster material comprising a first surface and an opposed second surface, a second layer of hardened plaster material comprising a first surface and an opposed second surface, wherein the first surface of the second layer faces the first surface of the first layer, and a viscoelastic interlayer disposed between the first surface of the first layer and the first surface of the second layer, wherein the interlayer includes a score-and-snap element.

Abstract: A security system for a personal computer, in which hardware and software are combined to provide a tamper-proof manner of protecting user-access and file-access. The hardware component of the system is an expansion board for insertion into an expansion slot of the PC, and has a first EPROM chip containing four portions of machine code for initializing system function calls and for establishing the proper boot-processing of the PC; a second RAM chip serving as scratch pad memory; a third EEPROM chip storing passwords, audit trail log, protection and encryption system flags, and user-access rights; a fourth automatic encryption and decryption chip for files of the PC; and a fifth clock chip for the audit trail. The software component includes a batch file that runs a program in conjunction with the machine code on the EPROM of the expansion board ensuring access is gained only for valid users.