SRC Forum - Message Replies

Forum: Reliability & Maintainability Questions and Answers

Topic: Reliability & Maintainability Questions and Answers

Topic Posted by: Reliability & Maintainability Forum (src_forum@alionscience.com )
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998

Original Message:

Posted by: Beth
Organization:UPCO
Date posted: Tue Jul 22 20:38:09 US/Eastern 2003
Subject: Comparing Reliability
Message:
Reliability of old system is .9958, new system is .9938. How do I calculate the reduction? I don't seem to be getting the same answer a previous report indicates, so... the report indicated 37 % decrease and I do not know where that came from nor do I know if its correct.

Previous reply

Reply:

Subject: Comparing Reliability
Reply Posted by: Igor (sf_tigor@bezeint.net )
Date Posted: Wed Nov 19 14:35:33 US/Eastern 2003
Message:
You can evaluate the reliability degradation by comparing the UNRELIABILITY figures (U)that are calculated as 1 - RELIABILITY. The first U is 0.0042 and the second U is 0.0062. The UNRELIABILITY incresed by 47.6% (0.0062/0.0042). Consequently, the RELIABILITY decresed similarly.