Information Technology Reference
In-Depth Information
Fig. 28 Fatigue lives scatter for E-glass/polyester ([90/0/
45/0] S ) from experiments (Mandell and
Samborsky 2010 ) along with the upper and lower bounds of NN-NARX model prediction for the
stress ratio R =
±
2
fields of appli-
cations, among others, (Hung and Kao 2002 ; Basso et al. 2005 ). Now, its appli-
cation has been extended in the
For
final remarks, NARX model has been employed in many
first time to spectrum fatigue life analysis and
assessment of composite materials.
6 Conclusions
Composite materials lifetime assessment using NN with NARX structure has been
presented in the present study. Dynamic nature of both the CLD and the NARX
model was emphasized and linked, resulting in the
first application of the NARX
model in spectrum fatigue analysis. Fatigue life assessment was realized as one-step
ahead prediction with respect to each stress level corresponding to stress ratio
values arranged in such a way that transition took place from a fatigue region to
another one in the CLD region. As a result, composite materials lifetime assessment
can be fashioned for a wide spectrum of loading and orientation in an ef
cient
manner. The simulation results hence showed the applicability and the ef
ciency of
the NN-NARX model when applied for different materials and loading situations as
well as axis orientations. A framework of arti
cial intelligence and system identi-
fication techniques therefore has been introduced and presented as a new approach
and perspective in the
field of fatigue life assessment of composite materials.
Search WWH ::




Custom Search