• 대한수학회논문집
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• 제15권4호
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• pp.627-640
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• 2000

In this paper, we shall prove a fixed point theorem which is more general than that of Ciric, Kannan and Rhoades.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제12권4호
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• pp.289-306
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• 2005

The aim of this paper is to prove some common fixed point theorems for six discontinuous mappings in non complete fussy metric spaces with condition of weak compatibility.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제16권4호
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• pp.345-357
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• 2009

We prove a related fixed point theorem for two pairs of mappings on two intuitionistic fuzzy metric spaces. Our result is maiden in this line.

• 대한수학회보
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• 제47권4호
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• pp.805-813
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• 2010

In this paper, we apply Bohnenblust-Karlins fixed point theorem to prove the existence of solutions for a class of fractional differential inclusions with separated boundary conditions. Some applications of the main result are also presented.

• 대한수학회지
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• 제40권4호
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• pp.681-693
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• 2003

In this paper, we first prove that there are no automorphism orbits accumulating at a boundary point of the largest isolated finite type. We also present a generalization of the results of Isaev and Krantz on the structure of the orbit accumulation points.

• Korean Journal of Mathematics
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• 제26권4호
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• pp.809-822
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• 2018

In this paper, we introduce complex valued dislocated metric spaces. We prove Banach contraction principle, Kannan and Chatterjea type fixed point theorems in this new space. Moreover, we give some applications of the results to differential equations and iterated functions.

• 충청수학회지
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• 제36권4호
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• pp.267-277
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• 2023

In this paper, we will first prove the linearity of additive mappings with bounded value near a point. And by using our theorem we will investigate the instability of the Cauchy equation in ℝ².

• Korean Journal of Mathematics
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• 제24권4호
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• pp.587-600
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• 2016

We obtain the general solution of the functional equation $f(ax+y)-f(x-ay)+{\frac{1}{2}}a(a^2+1)f(x-y)+(a^4-1)f(y)={\frac{1}{2}}a(a^2+1)f(x+y)+(a^4-1)f(x)$ and prove the stability problem of the quartic Lie ${\ast}$-derivation by using a directed method and an alternative fixed point method.

• 대한수학회보
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• 제43권4호
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• pp.679-692
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• 2006

On a compact oriented n-dimensional manifold $(M^n,\;g)$, it has been conjectured that a metric g satisfying the critical point equation (2) should be Einstein. In this paper, we prove that if a manifold $(M^4,\;g)$ is a 4-dimensional oriented compact warped product, then g can not be a solution of CPE with a non-zero solution function f.

• 대한수학회논문집
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• 제27권4호
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• pp.733-743
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• 2012

In the present paper, we prove common fixed point theorems for single-valued and set-valued occasionally weakly compatible mappings in Menger spaces. Our results improve and extend the results of Chen and Chang [Chi-Ming Chen and Tong-Huei Chang, Common fixed point theorems in Menger spaces, Int. J. Math. Math. Sci. 2006 (2006), Article ID 75931, Pages 1-15].