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The "Complete RG-improvement (CORGI)" serves to separate the
perturbation series into infinite subsets of terms which when
summed are renormalization scheme(RS)- Invariant. Crucially all
ultraviolet logarithms involving the dimensionful parameter, Q, on
which the observable depends are resumed, thereby building the
correct Q-dependence. We used from this idea and indicated that in
NNLO calculation as well as NLO calculation for when we have just
one renormalization scale or two renormalization and
factorization scales as it is appeared for moment of structure
functions, all unphysical parameters can be completely eliminated
from perturbative QCD predictions provided that all the
ultraviolet logarithms involving the physical energy scale Q are
completely resummed.
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