Biomedical Engineering Reference
In-Depth Information
4.6
Examples of two-parameter Weibull distribution. (a) Two
distributions of cumulative probability of failure,
P
f
, with different
parameters
. (b) Comparison of the corresponding first
derivatives (probability densities) of these distributions.
0
and
m
σ
As may be seen, the probability of failure increases with increasing
volume, because in larger volumes, larger defects are more likely to be
present. Considering two different volumes, V
1
and V
2
, and using equation
4.11 the relationship between their respective measured strengths is:
1
=
m
s
1
=s
2
¼ð
V
2
=
V
1
Þ
½
4
:
12
This fact must be kept in mind when comparing results obtained by different
