In the present paper, we consider a general class of operators enriched with some properties in order to act on $ C^{\ast }( \mathbb{R} _{0}^{+}) $. We establish uniform convergence of the operators for every function in $ C^{\ast }( \mathbb{R} _{0}^{+}) $ on $ \mathbb{R} _{0}^{+} $. Then, a quantitative result is proved. A quantitative Voronovskaya-type estimate is obtained. Finally, some applications are provided concerning particular kernel functions.
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