ML20254A331

Criticality Review Output File: (Attachment 2 to Email from W. Fowler (NAC) to N. Devaser (Nrc), NAC-LWT Bias Evaluation; Associated with Responses to the NRC RAI for NAC-LWT SAR, Revision 20B)

ML20254A331
Person / Time
Site:	07109225
Issue date:	04/23/2003
From:	NAC International
To:	Office of Nuclear Material Safety and Safeguards
NJDevaser NMSS/DFM/STL 415.5196
Shared Package
ML20254A327	List: ML20254A328 ML20254A329 ML20254A331
References
Download: ML20254A331 (3)

Text

uslstats: a utility to calculate upper subcritical limits for criticality safety applications Version 1.4, April 23, 2003 Oak Ridge National Laboratory Input to statistical treatment from file:enr_no_low.in

Title:

keff vs enrichment Proportion of the population

=.995 Confidence of fit

=.950 Confidence on proportion

=.950 Number of observations

= 40 Minimum value of closed band

= 0.00 Maximum value of closed band

= 0.00 Administrative margin

= 0.05 independent dependent deviation independent dependent deviation variable - x variable - y in y variable - x variable - y in y 7.91900E+01 9.90480E-01 4.31000E-03 9.31700E+01 9.97240E-01 4.42000E-03 7.91900E+01 9.97110E-01 4.81000E-03 9.31700E+01 9.96910E-01 4.02000E-03 7.91900E+01 9.97480E-01 4.91000E-03 9.31700E+01 1.00171E+00 4.02000E-03 7.94700E+01 9.93000E-01 4.41000E-03 9.31700E+01 9.96250E-01 4.02000E-03 7.94700E+01 9.91820E-01 4.41000E-03 9.31700E+01 9.95780E-01 4.02000E-03 7.94700E+01 9.93860E-01 4.41000E-03 9.31700E+01 9.94720E-01 4.02000E-03 7.94700E+01 9.95900E-01 4.41000E-03 9.31700E+01 9.93870E-01 4.01000E-03

7.94700E+01 1.00092E+00 4.41000E-03 9.31700E+01 9.91140E-01 4.01000E-03 7.94700E+01 1.00473E+00 4.41000E-03 9.31700E+01 9.95340E-01 4.01000E-03 7.94700E+01 1.00721E+00 4.41000E-03 9.31700E+01 1.00419E+00 4.02000E-03 7.94700E+01 1.00720E+00 4.41000E-03 9.31700E+01 9.96780E-01 4.02000E-03 7.94700E+01 1.00813E+00 4.41000E-03 9.31700E+01 1.00036E+00 4.01000E-03 7.94700E+01 1.00826E+00 4.41000E-03 9.31700E+01 9.92780E-01 4.01000E-03 7.94700E+01 1.01009E+00 4.41000E-03 9.31700E+01 9.90670E-01 4.01000E-03 7.94700E+01 9.88490E-01 4.41000E-03 9.31700E+01 9.99980E-01 4.02000E-03 7.94700E+01 9.96670E-01 4.40000E-03 9.32000E+01 9.92500E-01 8.10000E-03 7.94700E+01 1.00178E+00 4.41000E-03 9.32000E+01 9.92750E-01 8.10000E-03 7.94700E+01 1.00320E+00 4.40000E-03 9.32000E+01 9.92450E-01 8.10000E-03 7.94700E+01 1.00565E+00 2.04000E-03 9.32000E+01 9.92100E-01 8.10000E-03 7.94700E+01 9.95750E-01 4.81000E-03 9.32000E+01 9.91840E-01 8.10000E-03 chi = 2.5000 (upper bound = 9.49). The data tests normal.

Output from statistical treatment keff vs enrichment Number of data points (n) 40 Linear regression, k(X) 1.0252 + (-3.1941E-04)*X Confidence on fit (1-gamma) [input]

95.0%

Confidence on proportion (alpha) [input]

95.0%

Proportion of population falling above lower tolerance interval (rho) [input]

99.5%

Minimum value of X 7.9190E+01 Maximum value of X 9.3200E+01 Average value of X 8.6303E+01 Average value of k 0.99768

Minimum value of k 0.98849 Variance of fit, s(k,X)^2 2.9391E-05 Within variance, s(w)^2 2.3950E-05 Pooled variance, s(p)^2 5.3342E-05 Pooled std. deviation, s(p) 7.3035E-03 C(alpha,rho)*s(p) 2.8084E-02 student-t @ (n-2,1-gamma) 1.68660E+00 Confidence band width, W 1.2633E-02 Minimum margin of subcriticality, C*s(p)-W 1.5451E-02 Upper subcritical limits: ( 79.190 <= X <= 93.200 )

USL Method 1 (Confidence Band with Administrative Margin) USL1 = 0.9626 + (-3.1941E-04)*X USL Method 2 (Single-Sided Uniform Width Closed Interval Approach) USL2 = 0.9972 + (-3.1941E-04)*X USLs Evaluated Over Range of Parameter X:

X: 7.92E+1 8.12E+1 8.32E+1 8.52E+1 8.72E+1 8.92E+1 9.12E+1 9.32E+1 USL-1: 0.9373 0.9367 0.9360 0.9354 0.9348 0.9341 0.9335 0.9328 USL-2: 0.9719 0.9712 0.9706 0.9699 0.9693 0.9687 0.9680 0.9674 Thus spake USLSTATS Finis.

Plot file written to: enr_no_low.plt