• 제목/요약/키워드: Almost continuous

검색결과 400건 처리시간 0.022초

A MISCELLANY OF SELECTION THEOREMS WITHOUT CONVEXITY

  • Kim, Hoonjoo
    • 호남수학학술지
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    • 제35권4호
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    • pp.757-764
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    • 2013
  • In this paper, we give sufficient conditions for a map with nonconvex values to have a continuous selection and the selection extension property in LC-metric spaces under the one-point extension property. And we apply it to weakly lower semicontinuous maps and generalize previous results. We also get a continuous selection theorem for almost lower semicontinuous maps with closed sub-admissible values in $\mathbb{R}$-trees.

REMARKS ON γ-OPERATIONS INDUCED BY A TOPOLOGY

  • Min, Won-Keun
    • 대한수학회논문집
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    • 제26권2호
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    • pp.291-296
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    • 2011
  • Cs$\'{a}$sz$\'{a}$r [3] introduced the notions of ${\gamma}$-compact and ${\gamma}$-operation on a topological space. In this paper, we introduce the notions of almost ${\Gamma}$-compact, (${\gamma},{\tau}$)-continuous function and (${\gamma},{\tau}$)-open function defined by ${\gamma}$-operation on a topological space and investigate some properties for such notions.

NOTES ON γ-OPEN SETS DEFINED BY γ-OPERATION ON A SUPRATOPOLOGICAL SPACE

  • Kim, Young Key;Min, Won Keun
    • 충청수학회지
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    • 제32권2호
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    • pp.245-250
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    • 2019
  • In this paper, the notion of ${\gamma}$-operation on a supratopological space is introduced. We found that the ${\gamma}$-operation induces a supratopology (topology) containing a given supratopology. We also introduce the notions of (${\gamma}$, S)-continuous function and almost ${\Gamma}$-supracompact defined by ${\gamma}$-operation on a supratopological space and investigate some properties for such notions.

Almost Periodic Processes in Ecological Systems with Impulsive Perturbations

  • Stamov, Gani Trendafilov
    • Kyungpook Mathematical Journal
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    • 제49권2호
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    • pp.299-312
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    • 2009
  • In the present paper we investigate the existence of almost periodic processes of ecological systems which are presented with nonautonomous N-dimensional impulsive Lotka Volterra competitive systems with dispersions and fixed moments of impulsive perturbations. By using the techniques of piecewise continuous Lyapunov's functions new sufficient conditions for the global exponential stability of the unique almost periodic solutions of these systems are given.