Minimal repair model for systems under both unrevealed minor failures and unrevealed catastrophic failures

Optimal inspection and preventive maintenance of units with revealed and unrevealed failures

The maintenance of a single unit system that alternates operating and idle periods is studied. In the former case the failures are detected as soon as they occur and only by special testing or inspection in the latter. This paper aims at minimizing the cost per unit of time for an infinite time span by selection of a unique interval, for both inspection and maintenance. A special feature of thi...

Catastrophic failures of public health.

Sir—The arresting title of your Editorial (Mar 6, p 745) certainly caught my attention. It compares the “old” epidemics of infectious diseases (and the allegedly successful publichealth response to them) with the new epidemic of obesity, and the apparently complacent public-health response to it. But is it a true picture, both of the past and the present? The public-health “greats” (Semmelweiss...

Why Catastrophic Organizational Failures Happen

Vitality of Neural Networks under Reoccurring Catastrophic Failures

Catastrophic failures are complete and sudden collapses in the activity of large networks such as economics, electrical power grids and computer networks, which typically require a manual recovery process. Here we experimentally show that excitatory neural networks are governed by a non-Poissonian reoccurrence of catastrophic failures, where their repetition time follows a multimodal distributi...

Risk assessment of catastrophic failures in electric power systems

The declining reliability of the US electric power system is raising major concerns amongst both politicians and power engineers in the USA. One of the reasons put forward by the North Electric Reliability Council (NERC) is the detrimental role played by the protection systems during large disturbances, which tend to help the perturbations to propagate through over-tripping of fault free system...