Control and Cybernetics on Σ-porous and Φ-angle-small Sets in Metric Spaces

نویسندگان

  • Stefan Rolewicz
  • S. ROLEWICZ
چکیده

It is shown that in metric spaces each (α, φ)-meagre set A is uniformly very porous and its index of uniform v-porosity is not smaller than k−α 3k+α , provided that φ is a strictly k-monotone family of Lipschitz functions and α < k. The paper contains also conditions implying that a k-monotone family of Lipschitz functions is strictly k-monotone.

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تاریخ انتشار 2005