Handbook of Reliability, Availability, Maintainability and Safety in Engineering Design - Part 31 studies the combination of various methods of designing for reliability, availability, maintainability and safety, as well as the latest techniques in probability and possibility modelling, mathematical algorithmic modelling, evolutionary algorithmic modelling, symbolic logic modelling, artificial intelligence modelling, and object-oriented computer modelling, in a logically structured approach to determining the integrity of engineering design. . | Application Modelling of Reliability and Performance in Engineering Design 283 Fig. Design specification FMECA final absorption tower Total failures suspensions 72 Mean time to failure MTTF days The Kolmogorov-Smirnov goodness-of-fit test The Kolmogorov-Smirnov K-S test is used to decide if a sample comes from a population with a specific distribution. The K-S test is based on the empirical distribution function . whereby givenN ordered data points Y1 Y2 . YN the . is defined as EN n i N where n i is the number of points less than Y and the Y are ordered from smallest to largest value. This is a step function that increases by 1 N at the value of each ordered data point. An attractive feature of this test is that the distribution of the K-S test statistic itself does not depend on the cumulative distribution function being tested. Another advantage is that it is an exact test however the goodness-of-fit test depends on an adequate sample size for the approximations to be valid. The K-S test has several important limitations specifically It applies only to continuous distributions. It tends to be more sensitive near the centre of the distribution than at the tails. 284 3 Reliability and Performance in Engineering Design Table Acid plant failure data repair time RT and time before failure TBF Failure time RT min TBF day Failure time RT min TBF day Failure time RT min TBF day 7 28 01 0 00 38 0 9 25 01 0 00 31 5 11 9 01 0 00 360 1 7 30 01 0 00 35 2 9 27 01 0 00 79 2 11 10 01 0 00 430 1 7 31 01 0 00 148 1 9 29 01 0 00 346 2 11 20 01 0 00 336 10 8 1 01 0 00 20 1 9 30 01 0 00 80 1 11 26 01 0 00 175 6 8 5 01 0 00 27 4 10 1 01 0 00 220 1 11 28 01 0 00 118 2 8 7 01 0 00 15 2 10 4 01 0 00 63 3 12 1 01 0 00 35 3 8 11 01 0 00 5 4 10 7 01 0 00 176 3 12 2 01 0 00 556 1 8 12 01 0 00 62 1 10 8 01 0 00 45 1 12 5 01 0 00 998 3 8 13 01 0 00 580 1 10 10 01 0 00 52 2 12 6 01 0 00 124 1 8 14 01 0 00 897 1 10 10 01 0 00 39 0 12 11 01 0 00 25 5 8 15 .
