  Resorting to the Schwinger-boson representation for the description of a
localized magnetic-impurity state, we develop an RG-improved (renormalization
group) perturbation theory for the Kondo effect. This Schwinger-boson based
RG-improved perturbation theory covers the whole temperature range from a
decoupled local moment state to a local Fermi-liquid state through the
crossover temperature regime, shown from the specific heat and spin
susceptibility of the magnetic impurity. The Schwinger-boson based RG-improved
perturbation theory makes the strong coupling fixed point at IR (infrared)
accessible from the gaussian one at UV (ultraviolet) within the perturbation
framework, regarded to be complementary to the Schwinger-boson based NCA
(non-crossing approximation) self-consistent theory [Phys. Rev. Lett. {\bf 96},
016601 (2006)]. The existence of the perturbatively accessible strong coupling
fixed point implies the nature on the statistics of spinons, not determined by
hands but chosen by the nature of strongly coupled systems.
