• 한국통신학회논문지
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• 제29권11C호
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• pp.1491-1497
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• 2004

구현하기 위하여 고정 소수점 연산기에 적합하도록 최적화를 수행하였다. 최적화 과정은 크게 부호화기의 음질을 고려하여 프로세서의 데이터 워드 길이를 결정하는 과정과 자주 사용되는 초월 함수를 고정 소수점 연산을 통해 구현하는 것으로 구성된다. 데이터 워드 길이를 결정하기 위하여 심리음향 모델 과정의 고정 소수점 연산 오차와 이 오차가 비트 할당 과정에 영향을 미칠 확률 사이의 관계를 통계적 모델로 정의하였다. 여기서 정의된 모델을 사용하여 고정 소수점 연산 오차에 의한 영향이 1% 이내가 되도록 24비트의 데이터 워드를 선택하였다. 최적화된 고정 소수점 심리음향 모델을 사용한 MP3 부호화기의 음질은 부동 소수점 부호화기에 비해 W-R의 음질평가 점수를 기준으로 평균 -0.2 이내의 구분하기 힘든 수준의 음질 저하를 보였다

• Journal of applied mathematics & informatics
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• 제29권1_2호
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• pp.227-245
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• 2011

In this paper, we introduce a new iterative method for finding a common element of the set of solutions for mixed equilibrium problem, the set of solutions of the variational inequality for a ${\beta}$inverse-strongly monotone mapping and the set of fixed points of a family of finitely nonexpansive mappings in a real Hilbert space by using the viscosity and Ces$\`{a}$ro mean approximation method. We prove that the sequence converges strongly to a common element of the above three sets under some mind conditions. Our results improve and extend the corresponding results of Kumam and Katchang [A viscosity of extragradient approximation method for finding equilibrium problems, variational inequalities and fixed point problems for nonexpansive mapping, Nonlinear Analysis: Hybrid Systems, 3(2009), 475-86], Peng and Yao [Strong convergence theorems of iterative scheme based on the extragradient method for mixed equilibrium problems and fixed point problems, Mathematical and Computer Modelling, 49(2009), 1816-828], Shimizu and Takahashi [Strong convergence to common fixed points of families of nonexpansive mappings, Journal of Mathematical Analysis and Applications, 211(1) (1997), 71-83] and some authors.

• Journal of applied mathematics & informatics
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• 제17권1_2_3호
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• pp.329-341
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• 2005

In this paper, we introduce new random iterative sequences with errors approximating a unique random common fixed point for three random set-valued strongly pseudo-contractive mappings and show the convergence of the random iterative sequences with errors by using an approximation method in real uniformly smooth separable Banach spaces. As applications, we study the existence of random solutions for some kind of random nonlinear operator equations group in separable Hilbert spaces.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제19권4호
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• pp.397-407
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• 2012

Let X and Y be vector spaces. We introduce a new type of a cubic functional equation $f$ : $X{\rightarrow}Y$. Furthermore, we assume X is a vector space and (Y, N) is a fuzzy Banach space and then investigate a fuzzy version of the generalized Hyers-Ulam stability in fuzzy Banach space by using fixed point method for the cubic functional equation.

• Korean Journal of Mathematics
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• 제19권2호
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• pp.149-161
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• 2011

Using fixed point methods, we prove the generalized Hyers-Ulam stability of homomorphisms in Banach algebras and of derivations on Banach algebras for the following Jensen type functional equation: $$f({\frac{x+y}{2}})+f({\frac{x-y}{2}})=f(x)$$.

• 호남수학학술지
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• 제34권1호
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• pp.19-34
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• 2012

In this paper, we investigate the stability of a functional equation f(x+y+z)-f(x+y)-f(y+z)-f(x+z)+f(x)+f(y)+f(z) = 0 by using the fixed point theory in the sense of L. Cadariu and V. Radu.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제27권4호
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• pp.207-229
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• 2020

We establish fixed point and multidimensional fixed point results satisfying generalized (𝜓, 𝜃, 𝜑)-contraction on partially ordered non-Archimedean fuzzy metric spaces. By using this result we obtain the solution for periodic boundary value problems and give an example to show the degree of validity of our hypothesis. Our results generalize, extend and modify several well-known results in the literature.

• 충청수학회지
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• 제17권1호
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• pp.1-17
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• 2004

In this paper, the concept of semi-compatibility in Menger space is introduced and it is used to prove results on the existence of a unique common fixed point of four self-maps. These results are a very wide improvement of Mishra [8], Dedeic and Sarapa [3, 4], Cain and Kasril [1], and Sehgal and Bharucha Reid [10].

• East Asian mathematical journal
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• 제28권5호
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• pp.543-552
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• 2012

The aim of this paper is to prove a common fixed point theorem in normed linear spaces for discontinuous, occasionally weakly biased mappings without assuming completeness of the space. We give an example to illustrare our theorem. We also give an application of our theorem to best approximation theory. Our theorem improve the results of Gregus [9], Jungck [12], Pathak, Cho and Kang [22], Sharma and Deshpande [26]-[28].

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제26권4호
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• pp.267-276
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• 2019

In this paper, we investigate the stability of an additive-cubic-quartic functional equation f(x + 2y) - 4f(x + y) + 6f(x) - 4f(x - y) + f(x - 2y) - 12f(y) - 12f(-y) = 0 by applying the fixed point theory in the sense of L. Cădariu and V. Radu.