Comparison of Methodologies for the Safety and Dependability Assessment of an Industrial Programmable Logic Controller
نویسندگان
چکیده
Computer based systems, which are devoted to control critical functions, may incur in safety and dependability problems. In the safety area a new standard is currently emerging, IEC 61508, which is intended to provide a unified framework which may deserve as guideline for the analysis of safety related systems. The present paper deals with the safety and dependability analysis of a Programmable Logic Controller (PLC) according to the requirements of IEC 61508. In order to gain insight on the system characteristics and on the used methodologies, different probabilistic techniques of increasing modeling power (Fault Tree (FT), Bayesian Networks (BN), Generalized Stochastic and Stochastic Well formed Petri Nets (GSPN and SWN) have been compared.
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تاریخ انتشار 2001