Forum: Reliability & Maintainability Questions and Answers
Posted by: Sadat Hussain (email@example.com )
Date posted: Tue Mar 5 14:48:48 US/Eastern 2002
Subject: ASIC Soft Errors
I need to know how soft errors happen in either ASIC memory or flip flops. What are some typical ASIC soft error rates? Compared to hard or "stuck at" faults how do SERs affect the reliability of an ASIC?
Posted by: Andrew Comons
Date posted: Mon Mar 4 20:47:32 US/Eastern 2002
Subject: MTBF and Redundent Systems
I am trying to write a system specification
for equipment which will be fielded in pairs, the second system will act as backup system. Each system will be required to have a spare parts package on-board, where the fulltime attending operator will be required to employ built in diagnostics and correct faults within a period of 5 minutes. If faults can't be corrected in 5 minutes the decision is to switch to the backup system. Mission duration is 120 hours. Reliability goal is 95%. I need to determine MTBF of the system, including the redundent but I do not know how to account for a failure if it is correctable by the 5 minute fault detection/correction requirement. Sample calcs, references or advice available? Thanks in advance.
Posted by: Brenda Ortiz (firstname.lastname@example.org )
Date posted: Wed Feb 27 22:33:17 US/Eastern 2002
Subject: Reliability Model for Permanent Magnet Motor
I'm working on a reliability prediction for a Permanent Magnet Motor. I was looking at MIL-HDBK-217 but the model is for motros below 1HP and also to Hadbook of Reliability Prediction Procedures for Mechanical Equipment (David Taylor Research Center) but in the other way this one is too sophisticate. Did you know about any other method/reference to get the model?
Posted by: Sheila Prather (email@example.com )
Organization:Northrop Grumman Corporation
Date posted: Wed Feb 27 10:33:58 US/Eastern 2002
Subject: ESS Screening Strength Assessment - Mil-Hdbk-344A
I've used Mil-Hdbk-344A to calculate the screening strength at different levels of assembly, e.g., SRU and LRU levels for the system under evaluation. I now want to compute the overall system level screening strength given the lower level results. Any recommendations as to how the two sets of data should be combined?
Posted by: Ks
Date posted: Fri Feb 22 10:01:21 US/Eastern 2002
Subject: adobe error
I am getting this error from adobe reader "the file was damaged and could not be repaired" whenever I click on the button on the web page to view the pdf file.
Can anyone help with this?