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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. We studied polarized valon
distributions which have an important role in describing the spin
dependence of parton distribution in leading order and
next-to-leading order approximation. Convolution integral in frame
work of valon model as a useful tool, was used in polarized case.
To obtain polarized parton distributions in a proton we need to
polarized valon distribution in a proton and polarized parton
distributions inside the valon. We employed Bernstein polynomial
averages to get unknown parameters of polarized valon
distributions by using to available experimental data.
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