• Bulletin of the Korean Mathematical Society
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• v.61 no.1
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• pp.207-216
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• 2024

This note is devoted to establishing the variation continuity of the one-dimensional discrete uncentered multilinear maximal operator. The above result is based on some refine variation estimates of the above maximal functions on monotone intervals. The main result essentially improves some known ones.

• Journal of the Society of Disaster Information
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• v.20 no.2
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• pp.245-256
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• 2024

Purpose: Securing the continuity of essential functions in the private sector and ensuring the stability of people's daily lives. Method: Based on the national core-based management targets, private sectors in areas directly related to people's lives are selected. Presents standards for establishing functional continuity plan obligations. Result: Establishing the scope of establishing a functional continuity plan in five areas that have not been designated as mandatory in the private sector and presenting standards based on this. Conclusion: In disaster situations, functional continuity of the private sector, which is directly related to people's lives, can be secured to maintain people's daily lives and establish a social safety net.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.3 no.2
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• pp.200-205
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• 2003

In this paper, we generally introduce some of the terminology of Yalvac [10] and Azad [4] in intuitionistic fuzzy topological spaces. In addition to the fundamental concepts of intuitionistic fuzzy sets, we emphasize the usefulness of the concepts of intuitionistic fuzzy points intuitionistic fuzzy elementhood. Mainly, this paper is devoted to the study of intuitionistic fuzzy topological spaces with specific attention to the weaker forms of fuzzy continuity.

• East Asian mathematical journal
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• v.19 no.2
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• pp.241-249
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• 2003

In [11] the feeble continuity is introduced and then the weak and strong forms of feeble(or, equivalently $\alpha$-continuity) continuity are studied. In this note, we introduce a type of function called a slightly $\alpha$-continuous function and study several properties of it

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.1 no.1
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• pp.69-74
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• 2001

We introduce fuzzy semi-regular spaces. Furthermore, we investigate the relations among fuzzy super continuity, fuzzy $\delta$-continuity and fuzzy almost continuity in fuzzy topological spaces in view of the definition of Sostak. We study some properties between them.

• East Asian mathematical journal
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• v.39 no.2
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• pp.119-139
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• 2023

Most of calculus and real analysis are concerned with the study on continuous functions. Because of self-sustaining concept caused by everyday language, continuity has difficulties. This kind of viewpoint is strengthened with that teacher explains continuity by graph drawn ceaselessly and so finally confused with mathematics concept which is continuity and connection. Thus such a concept image of continuity becomes to include components which create conflicts. Therefore, we try to analyze understanding of continuity on university students by using the concept image as an analytic tool. We survey centering on problems which create conflicts with concept definition and image. And we investigate that difference of definition in continuous function which handles in calculus and analysis exists and so try to present various results on university students' understanding of continuity concept.

• The Pure and Applied Mathematics
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• v.12 no.1
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• pp.47-55
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• 2005

For topological spaces X, Y and the function f : X → Y, it induces a function gr(f) : X → X x Y defined as gr(f)(χ) = (χ, f(χ)), for every χ ∈ X. It deals with some preliminary investigations relating to the behavior of functions and its graph functions. It has also been found that continuous functions are homotopic if and only if their graph functions are homotopic.

• East Asian mathematical journal
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• v.19 no.2
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• pp.291-303
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• 2003

A result of Hardy and Littlewood relates Holder continuity of analytic functions in the unit disk with a bound on the derivative. Gehring and Martio extended this result to the class of uniform domains. In this paper we obtain a similar result to the class of uniformly John domains in terms of the inner diameter metric. We give several properties of a domain with the property. Also we show some results on the Holder continuity of conjugate harmonic functions in the above domains.

• Bulletin of the Korean Mathematical Society
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• v.39 no.4
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• pp.535-541
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• 2002

In this paper, we introduce the concept of lower semi-continuous from above functions and show that many well-known results, such as Ekland's and Caristi's theorems, remain also true under lower semi-continuous from above functions.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.9 no.1
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• pp.47-52
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• 2009

We introduce the concepts of interval-valued fuzzy M-continuity and interval-valued fuzzy M$^*$(M)-open mappings. And we study some characterizations and basic properties of such functions.