9

8

7

6

5

4

3

2

1

0

2 3.5

5 6.5

8 9.5

11

0.5

Longitudinal

Lognormal

0.439 m/sec

1.67 m/sec

2 m/sec (6 ft/sec)

x-velocity

(1.44 ft/sec)

(5.5 ft/sec)

Transverse

Lognormal

0.0146 m/sec

0.026 m/sec

0.3 m/sec (1 ft/sec)

y-velocity

(0.048 ft/sec)

(0.083 ft/sec)

Angle (degrees)

Lognormal

1.176 m/sec

0.704 m/sec

None

(3.86 ft/sec)

(2.31 ft/sec)

(5) The spreadsheet developed for this example uses the empirical equation discussed in para-

graph B-3 of this ETL. The data input to the cells for this example are shown in Figure D-8. @Risk uses

the calls of "RiskLognorm" within a cell to define the lognormal random variable with its mean and

standard deviation. The "RiskTruncate" command limits the sampling of the distribution above those

values. The output for *F*m uses the "RiskOutput" command and the empirical equation follows the name.

Uncertainty in the empirical model is not included in this example for simplicity. Based on the processing

of the data to define the empirical equation as discussed in Appendix E, the standard deviation (or error)

in the empirical model is 351 kN (79 kips). This would need to be included in the PBIA as approxi-

mately a 10 percent coefficient of variation during the simulation of impact force results. These varia-

tions of the model would be represented by a cone shape running from 0 to 800 kips, which is shown in

Appendix E, Figure E-3. These values input to the spreadsheet cells reflect the values from Table D-3.

D-7

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