Reliability HotWire: eMagazine for the Reliability Professional
In this issue:

Issue 55, September 2005

*Hot Topics
*Reliability Basics
*Tool Tips
*Hot News
*Contribute to HotWire

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Hot Topics

Applications of the Weibull-Bayesian Distribution in Life Data Analysis

One of the new features of Weibull++ 7 is support for Bayesian statistics. In Version 6, all types of analysis dealt exclusively with classical statistics. The premise of Bayesian statistics is to incorporate prior knowledge along with a given set of current observations in order to make statistical inferences. The prior information could come from operational or observational data, from previous comparable experiments or from engineering knowledge.


This type of analysis is particularly useful if there is a lack of current test data and when there is a strong prior understanding about the parameter of the assumed life model and a distribution can be used to model the parameter. By incorporating prior information about a parameter, a posterior distribution for a parameter can be produced and an adequate estimate of reliability can be obtained. Weibull++ 7 introduces a new type of distribution that combines the properties of the Weibull distribution with the concepts of Bayesian statistics. The new distribution is called Weibull-Bayesian. The Reliability Basics section of this HotWire issues introduces the theory behind the Weibull-Bayesian model. This article presents two examples that illustrate the application of the Weibull-Bayesian distribution.

To read more, see 

Reliability Basics

Introduction to the Weibull-Bayesian Distribution

This article describes Bayesian concepts, their applications in life data analysis and the Weibull-Bayesian distribution introduced in Weibull++ 7.

To read more, see 

Tool Tips
  • Two components are arranged in a series configuration. There is a probability p that the two components would fail when they are put together in the system. How could BlockSim model this situation?

  • How can interactions be modeled in ALTA if one or more of the factors is a categorical factor?

  • In RENO, can a simulation of the Flowchart be followed in detail to make sure it works the way it is intended?

To read more, see 

Latest Software Updates
A new service release is now available for Lambda Predict (SR 1.0.1). In addition, Xfmea 3 Enterprise (3.0.1) and RENO (1.0.1) have been officially released. To determine the compile revision of the application on your computer, select About from the Help menu. More Software Downloads...


Application Date Created Version
Xfmea Enterprise 9/6/05 3.0.1
Xfmea Enterprise Update N/A N/A
Lambda Predict    
Lambda Predict 9/7/05 1.0.1
Lambda Predict Update N/A SR 1.0.1
RENO 8/8/05 1.0.1
RENO Update N/A N/A
Hot News
* Save on Weibull++ 7 Now ReliaSoft is working to release Weibull++ 7 by the end of this month. Therefore, we want to remind you that any Weibull++ 6 Standard Single User License that is purchased during the month of September will automatically receive a free upgrade (20% savings). For those who currently own Weibull++ 6, we are offering a 10% discount on the Weibull++ 7 upgrade price. The list of Weibull++ 7's new and enhanced features is available on the Web at
* Call for Presentations Do you have a success story related to reliability engineering? Do you have some testing and analysis that you are really proud to have accomplished? There are numerous engineers out there who could benefit from your experience. The 2006 International Applied Reliability Symposium, slated for Orlando, FL on June 14 - 16, 2006, is currently accepting presentation proposals that address the Symposium theme: "Sharing applications, success stories and lessons learned in reliability and maintainability engineering." The deadline for proposal submissions is October 31, 2005. For more information, please visit the ARS Web site at or e-mail
* Dr. Larry Crow in China - ReliaSoft China is currently touring key customer sites with Dr. Larry Crow to help promote the benefits of reliability growth analysis. Dr. Crow also taught a 3-day RGA course in Beijing earlier in the month. If you or an engineer you work with in China would like to learn more about training and education within that region of the world, please contact ReliaSoft China for additional details.
Public Training Event Calendar
September/October 2005
September 26 - 28, 2005: RS 522 Advanced System Reliability, Maintainability and Availability Analysis in Tucson, Arizona
September 29 - 30, 2005: RS 470 FMEA/FMECA and Xfmea in Tucson, Arizona
October 5 - 7, 2005: RS 525 Advanced Probabilistic and Risk Decision Analysis and RENO in Tucson, Arizona
November 2005
November 14 - 18, 2005: MSMT Foundations in Tucson, Arizona
November 14 - 18, 2005: MSMT Foundations in Singapore
November 21 - 25, 2005: MSMT Foundations in Melbourne, Australia
More Reliability Training Seminars...
Contribute to HotWire
Contributions Welcomed
As always, your feedback and contributions are appreciated. ReliaSoft is able to provide the most user-friendly reliability software packages and support because we listen to our customers. This applies to our newsletters and publications as well. We welcome any suggestions or contributions you may have for Reliability HotWire. If you have a topic or article that you think would be useful to the readers of Reliability HotWire, feel free to contact us.

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