Preventive maintenance is required to keep critical systems available at reasonable costs. Instead of applying the traditional experience-based approach of statistical analysis of failure data, the present paper proposes to adopt a predictive maintenance policy that relies on detailed knowledge of the physical failure mechanisms. A structured scheme for this approach is presented. Then three ca...

We describe a simulator for modeling complex control dynamics in optical line systems involving the interaction of multiple transmission, control, and monitoring elements in response to channel changes, component failure, and recovery events.

In many cases, redundant systems are beset by both independent and dependent failures. Ignoring dependent variables in MTBF evaluation of redundant systems hastens the occurrence of failure, causing it to take place before the expected time, hence decreasing safety and creating irreversible damages. Common cause failure (CCF) and cascading failure are two varieties of dependent failures, both l...

abstractbackgroundline of treatment for management of hydrocephalus despite available new techniques andsystems of shunting. associated complications should be recognized and managed properly,but the most recognized complications are shunt obstruction which its prevalencethrough surgical approach is discussed here. two approaches (frontal and parietal) are usedto insert ventriculoperitoneal shu...

Power electronic devices are susceptible to catastrophic failures when they are exposed to energetic particles; the most serious failure mechanism is single event burnout (SEB). SEB is a widely recognized problem for space applications, but it also may affect devices in terrestrial applications. This phenomenon has been studied in detail for power MOSFETs, but much less is known about the mecha...

This dissertation contains contributions to the management of optical transport networks. The focus is on traffic modeling, analysis of failure mechanism, and the development of a novel semi-automatic network management system. The developed service oriented traffic models serve as input parameters for the network management system and include the special routing of the analyzed services. An ev...

Wafer-level testing of surface-micromachined sensors provides ncw challenges to the test community. Currently, there is no method available for performing direct measurements to assess faulty micromechanical structures. Most commercial methods use electrical measurements to deduce the physical source of failures in the micromechanical structure. As a result, the process of identifyang various f...

Traditionally the statistical or more specifically probabilistic methods form the basic framework for assessing the reliability characteristics of the components. However the recent trend for predicting the reliability or life of the component involves application of physics-offailure methods. This rather new approach is finding wider application as it is based on basic fundamentals of science ...

The physics of failure (POF) is an approach to designing reliable products to avoid failure, based on the knowledge of root cause failure mechanisms. It is based on failure reliability technology that studies the failure regularities from the failure reasons and failure mechanisms of the products. A clear understanding of the physics-of-failure is necessary in applications that afford little op...

In a system subject to both repairable and catastrophic (i.e., nonrepairable) failures, ‘mission success’ can be defined as operating for a specified time without a catastrophic failure. We examine the effect of a burn-in process of duration t on the mission time x, and also on the probability of mission success, by introducing several functions and surfaces on the ðt; xÞ-plane whose extrema re...