Failure rate and average repair time of input-bus unit were calculated by state Spaces method. Power reliability indices of whole systems were computed by min-cut method.

Across the country, we lose an average of seven billion gallons of drinking water a day to leaks-and we have an 800, 000-mile network of pipes that needs constant monitoring and repair.

The average survival period of perforation repair, partial gastrectomy radical gastrectomy, is 9.5 months 14 months and 26.2 months respectively.