Forum: Reliability & Maintainability Questions and Answers
Posted by: IC Date posted: Wed Jun 12 4:44:46 US/Eastern 2002 Subject: CHINA 299B Message: I recently came across a reference to CHINA 299B - a reliability standard. Can anybody provide some information on this. Thanks
Posted by: Johnson Wood (wuxiangping@huawei.com ) Date posted: Fri May 24 4:23:19 US/Eastern 2002 Subject: The value of reliability prediction Message: Reliability prediction is an important technique in reliability engineerig. But now, many people have doubts on its value. Because the prediction results are often quite different from the actual performance. Is reliability prediction useless?
Posted by: Stefano Stanghellini (stefano.stanghellini@transport.alstom.com ) Organization:ALSTOM TRANSPORT IS Date posted: Thu May 23 9:51:57 US/Eastern 2002 Subject: Reliability assumption Message: I performed a safety study where only some particulare failure modes can cause the hazardous situation. In particualar I have to evaluate what is the probability to have railway signal blinking due toa failure. The situation is dangerous only if the signal blinks with a frequency i a range between 0.1 to 10 Hz. In my analysis I identified some integrated circuit which can self oscillate due to a failure and cause the dangerous situation. The considered components are designed to work till a frequency of about some Mhz. Because I have no information available about the failure mode distribuition, in my analysis I consider that the probability to fail at a certain frequency is homogemeous. In this way for the hazardous failure rate I considered a ratio of the total failure rate. The ratio I took into account was equal to: (dangerous frequency)/1Mhz. Somebody ask me to justify this assumption because seems to be not conservative. Can anybody help me? Is there some data i leterature about this kind of failure?
Posted by: Jean-Marie CLOAREC (Jean-Marie.Cloarec@ligeron.com ) Organization:LIGERON SA Date posted: Wed May 22 12:13:40 US/Eastern 2002 Subject: Time definition Message: Can anyone give me the definition/difference between "elapsed time" and "operating time". Which of this 2 times must be used for FMECA, prédictions, .. Thanks
Posted by: Rick Johnson (rjohnson@systems.textron.com ) Date posted: Tue May 14 12:44:01 US/Eastern 2002 Subject: Long term storage of Laptop Computer Message: Are there any issues with the long term (upto 10 years) dormant storage of laptop computers? Hard drive sticking, etc.
|