1. Although reliability and maintainability assume that there are only two cases, broke and not broke, the truth of the world is that we do not and never have lived in a bipolar world. There are shades of working systems. The gray zone includes things that work sometimes, usually only when the mechanic is not looking. 2. Prognosis is the art of the foreseeable future. However the future is inferred with limited insight into equipment usage and environment. Both are subject to wide variations in uncertainty. 3. Wear (degradation) is a measurable phenomenon that can be modeled and simulated. The ability to accomplish this is essential to V&V. And as with most phenomenon, its properties can be described in virtual to real worlds. 4. Component wear contributes to system failure. This is the science of reliability. 5. Component measurement does not always detect maintenance realities. That is, components can be removed early and system failure can occur before any single component fails completely. 6. Uncertainty is compensated for by excessive inspection, sparing and MMH's for troubleshooting and incorrect maintenance, i.e. CND's, RETOK's, BCS's etc. 7. To understand prognostics there must be an understanding of the physics of failure. 8. In the computationally dependent world we live in, there must also be an understanding of the phenomena of software failure. Although in the literal sense, software does not fail, there are occasions where programs do not produce the results that were expected. 9. Because of the complexity and interrelated nature of the systems under consideration, prognostics must be conscious of the nature and issues involved in integration. 10. Prognostics must combine systems engineering processes with the appropriate tool sets and data. The field of prognostics will require additional tools and a shifting of paradigms from component and bipolar computation to system performance and gray scale capabilities. 11. This leads to the development of degradation tools that consider wear and project life remaining. Instead of FMEA and FMECA, Degradation Mode Effects Analysis and Degradation Mode Effect Criticality Analysis tools will be needed to start and maintain the systems engineering process to sustain prognostics.
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