An article in Microelectronics Reliability [Advanced Electronic Prognostics through System Telemetry and Pattern Recognition Methods, (2007, 47(12), pp. 18651873)] presented an example of electronic prognostics

An article in Microelectronics Reliability [€œAdvanced Electronic Prognostics through System Telemetry and Pattern Recognition Methods,€ (2007, 47(12), pp. 1865€“1873)] presented an example of electronic prognostics (a technique to detect faults in order to decrease the system downtime and the number of unplanned repairs in high-reliability and high-availability systems). Voltage signals from enterprise servers were monitored over time. The measurements are provided in the following table.

(a) Using all the data, compute trial control limits for individual observations and moving-range charts. Construct the chart and plot the data. Determine whether the process is in statistical control. If not, assume that assignable causes can be found to eliminate these samples and revise the control limits.

(b) Estimate the process mean and standard deviation for the in-control process.

(c) The report in the article assumed that the signal is normally distributed with a mean of 1.5 V and a standard deviation of 0.02 V. Do your results in part (b) support this assumption?

Voltage Signal Voltage Signal Observation Observation 1.498 26 1.510 1.521 1.494 27 1.507 3 1.500 28 1.495 4. 29 1.493 1.502 30 1.499 1.509 31 1.509 1.491 1.480 32 8 1.490 33 1.478 1.486 34 1.495 10 1.510 35 1.482 11 1.495 36 1.488 12 1.481 37 1.480 13 1.529 38 1.519 14 1.479 39 1.486