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Due to uncertainty which is coming from renormalization and
factorization scale dependence of finite order perturbation
calculations in the total cross section of $b\bar{b}$ production,
there will be sizable discrepancy between experimental data and
theoretical results on the $b\bar{b}$ production in $p\bar{p}$
collisions. Parton distribution functions are obtained, using
valon model where the valon representation provides a basis
between hadrons and quarks, in terms of which the bound-state and
scattering properties of hadrons can be united and described. The
approach of "Complete RG-improvement (CORGI)" will be employed in
which one should perform a resummation to all-orders of
renormalization and factorization group -predictable terms at each
order of perturbation theory so as the scales dependence will be
avoided and as we expect there will be a significantly reduction
for mentioned discrepancy in the total cross section of heavy
quark productions.
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