X is belonged "32.1 -6.7×Ln (Y)".

The revision coefficient K is calculated out with dividing this fixed number part by average 4. 17. Thus, the estimate values of the man-hour is calculated by using expression 1 and 2, it is showen as follows.

Z=7.7X - 1.6X×Ln (Y) (3)

Z: Estimate man-hour Y: Evaluation mark total values

According to previous example, X=2.71, total mark of evaluation is 48 points. An estimate man-hour Z is Y=7.7×2.71 - 1.6×2.71×Ln (48) =4.09 MH/case, and statistics actual values is 3.25 MH/case in this case.

For estimate man-hour about the typical equipment, it writes down the mark tables of evaluation for maintenance on Table 6,7 and 8. Table 9 is man-hour estimation table which is shown typicaly type of ocean going vessel ; 24000KW Container vessel. And it writes down a comparative graph with a man-hour statistic result of the equipment and an estimate man-hour in Figure 2.

　

Table 6 Mark of Environment for Maintenance

Table 7 Mark of Repairer's Ability

　

As for the coefficient of correlation among both is 0.895. Next, it compared a man-hour statistic actual values and the estimate man-hour about each ship classification on average two personnels.

　

Table 8 Mark of Supporting ability

　

Generally speaking, man-hour from the statistical data are bigger than the estimate values of man-hour. However, the coefficient of correlation among both is between 0.96.

The latter's man-hour, heat exchanger, main engine and exhaust gas economizer on VLCC or Bulk Carrier have twice values. As for the coefficient of correlation among both is between 0.72 and 0.86. And, it is making a correlation values decline in nearly 0.4 in the case to change the number of the personnel on same kind of vessel. Also, according to increase the number of repairers on auxialy boiler, deck machinery and exhaust gas economizer, the error is increasing to 5 times.

These equipment much heavy failure rather than general failure. It supposed to take a lot of man-hour because it needs restration urgently.

According to the Fig 2, it is supposed that the man-hour of navigation instrument have high values due to limited times for operation, then restration work is done by the outside support mainly.

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