| 摘要 |
<p>A control system for use in connection with one or more facilities comprising means for receiving information identifying a particular token, which system is operable so as, when intermittently presented with the token after receiving said identifying information, to recognise that token as a key and to permit access to and/or operation of one or more of the facilities until a predetermined time has elapsed or a selected event has occurred and until then not to recognise tokens of other random users, and thereafter no longer to permit access to and/or operation of the or each facility until further identifying information relating to a valid token is received.</p> |
