A single point of failure (SPOF) in system operations is a weak point of system reliability. Mean time to failure (MTTF) of system operations is equal to the shortage component’s MTTF in system. A Tier IV data center is designed to eliminate the SPOF. Data center system reliability is not only depended on the MTTF of each component in the system, but also relies on the mean time to repair (MTTR...

Starting with the meaning of the word quality, diverse concepts connoted by the term are examined. Instead of a bathtub curve, the desirable shape of a failure rate covering the entire life of a good product, which might be called hockey-stick line, is introduced. From the hockey-stick line and the definition of reliability, two measurements are extracted. The terms r-reliability (failure rate)...

This study quantifies the uncertainties in winds measured by the Aberystwyth Mesosphere–Stratosphere– Troposphere (MST) radar (52.4 N, 4.0 W), before and after its renovation in March 2011. A total of 127 radiosondes provide an independent measure of winds. Differences between radiosonde and radar-measured horizontal winds are correlated with long-term averages of vertical velocities, suggestin...

Modeling the reliability of distributed systems requires a good understanding of the reliability of the components. Careful modeling allows highly fault-tolerant distributed data applications to be constructed at the least cost. Failure and repair rates of components are o f e n assumed to be exponentially distributed. This hypothesis is testable f o r failure rates, though the process of gathe...