• Nonlinear Functional Analysis and Applications
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• v.26 no.5
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• pp.1059-1075
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• 2021

In this paper, we unify and enrich the well-known classical metrical coincidence theorems on a complete metric space due to Machuca, Goebel and Jungck. We further extend our newly proved results on a subspace Y of metric space X, wherein X need not be complete. Finally, we slightly modify the existing results involving (E.A)-property and (CLR_g)-property and apply these results to deduce our coincidence and common fixed point theorems.

• Nonlinear Functional Analysis and Applications
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• v.26 no.3
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• pp.565-580
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• 2021

In this paper, first of all we prove a fixed point theorem for 𝜓_∫𝜑-weakly contractive mapping. Next, we prove some common fixed point theorems for a pair of weakly compatible self maps along with E.A. property and (CLR) property. An example is also given to support our results.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.12 no.1
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• pp.1-6
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• 2008

Duggal-Jeon-Kubrusly([2]) introduced Hilbert space operator T satisfying property ${\mid}T{\mid}^2{\leq}{\mid}T^2{\mid}$, where ${\mid}T{\mid}=(T^*T)^{1/2}$. In this paper we extend this property to general version, namely property B(n). In addition, we construct examples which distinguish the classes of operators with property B(n) for each $n{\in}\mathbb{N}$.

• Bulletin of the Korean Mathematical Society
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• v.48 no.4
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• pp.779-789
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• 2011

In this paper we study the Banach space $L^1$(G) of real valued measurable functions which are integrable with respect to a vector measure G in the sense of D. R. Lewis. First, we investigate conditions for a scalarly integrable function f which guarantee $f{\in}L^1$(G). Next, we give a sufficient condition for a sequence to converge in $L^1$(G). Moreover, for two vector measures F and G with values in the same Banach space, when F can be written as the integral of a function $f{\in}L^1$(G), we show that certain properties of G are inherited to F; for instance, relative compactness or convexity of the range of vector measure. Finally, we give some examples of $L^1$(G) related to the approximation property.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.1
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• pp.167-175
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• 2018

In this paper we show that two notions of the average shadowing property and the hyperbolicity are equivalent in linear dynamical systems on the vector space ${\mathbb{C}}^n$.

• Journal of the Korean Mathematical Society
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• v.58 no.1
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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.

• Korean Journal of Mathematics
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• v.20 no.3
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• pp.353-360
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• 2012

In this paper we introduce the property (C), which is a cone metric extension of the usual metric property (E,A) and consider fixed point theorems for generalized contractive mappings under suitable conditions in cone metric spaces without normal cones.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.9A
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• pp.1039-1047
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• 2004

In this paper, we propose a new channel estimation technique for long code DS-CDMA DMB down link system which estimate the channel response based on the signal space vector only, unlike the most conventional sub-space method relying on the orthogonal property of noise space vectors to the signal space vector. Because of this property of the proposed method, very optimum covariance matrix in its dimension can be used in subspace analysis channel estimation technique otherwise it is likely too large to be implemented practically.

• Communications of the Korean Mathematical Society
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• v.13 no.4
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• pp.775-780
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• 1998

In this paper it is shown that Dunford-Pettis operators obey the "Pettis-divisor property": if T is a Dunford-Pettis operator from $L_1$($\mu$) to a Banach space X, then there is a non-Pettis representable operator S : $L_1$($\mu$)longrightarrow$L_1$($\mu$) such that To S is Pettis representable.

• The Bulletin of The Korean Astronomical Society
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• v.33 no.2
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• pp.60.2-60.2
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• 2008