• 충청수학회지
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• 제24권1호
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• pp.59-64
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• 2011

In this paper, we show that every $C^1$-robustly positively expansive map is expanding.

• 대한수학회보
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• 제57권3호
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• pp.569-581
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• 2020

In this paper, we introduce the new general concept of usual expansiveness which is called "positively weak measure expansiveness" and study the basic properties of positively weak measure expansive C¹-differentiable maps on a compact smooth manifold M. And we prove that the following theorems. (1) Let 𝓟𝓦𝓔 be the set of all positively weak measure expansive differentiable maps of M. Denote by int(𝓟𝓦𝓔) is a C¹-interior of 𝓟𝓦𝓔. f ∈ int(𝓟𝓦𝓔) if and only if f is expanding. (2) For C¹-generic f ∈ C¹ (M), f is positively weak measure-expansive if and only if f is expanding.

• 충청수학회지
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• 제27권1호
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• pp.151-155
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• 2014

In this paper, we introduce some examples of measure expansive maps.

• 대한수학회지
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• 제58권1호
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• pp.207-218
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• 2021

In this paper, the notion of two-sided limit shadowing property is considered for a positively expansive open map. More precisely, let f be a positively expansive open map of a compact metric space X. It is proved that if f is topologically mixing, then it has the two-sided limit shadowing property. As a corollary, we have that if X is connected, then the notions of the two-sided limit shadowing property and the average-shadowing property are equivalent.

• 충청수학회지
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• 제15권1호
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• pp.7-23
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• 2002

We introduce the notion of expansivity for a continuous surjection on a compact metric space, as the positively and negatively expansive map. We also prove that some well-known properties about positively expansive maps in [2] hold by using our definition.

• 대한수학회논문집
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• 제37권4호
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• pp.1249-1258
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• 2022

In this study, we show that the strong exponential limit shadowing property (SELmSP, for short), which has been recently introduced, exists on a neighborhood of a hyperbolic set of a diffeomorphism. We also prove that Ω-stable diffeomorphisms and 𝓛-hyperbolic homeomorphisms have this type of shadowing property. By giving examples, it is shown that this type of shadowing is different from the other shadowings, and the chain transitivity and chain mixing are not necessary for it. Furthermore, we extend this type of shadowing property to positively expansive maps with the shadowing property.

• 충청수학회지
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• 제11권1호
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• pp.73-85
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• 1998

This paper deals with the topological stability of continuous maps. First, the notion of local expansion is given and we show that local expansions of compact metric spaces have the shadowing property. Also, we prove that if a continuous surjective map f is a local homeomorphism and local expansion, then f is topologically stable in the class of continuous surjective maps. Finally, we find homeomorphisms which are not topologically stable.