• Korean Journal of Mathematics
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• 제26권1호
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• pp.75-85
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• 2018

In this paper, we study nonconstant warping functions on an Einstein warped product manifold $M=B{\times}_{f^2}F$ with a warped product metric $g=g_B+f(t)^2g_F$. And we consider a 2-dimensional base manifold B with a metric $g_B=dt^2+(f^{\prime}(t))^2du^2$. As a result, we prove the following: if M is an Einstein warped product manifold with a 2-dimensional base, then there exist generally nonconstant warping functions f(t).

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제26권2호
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• pp.59-73
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• 2019

In this paper, a version of the boundary Schwarz Lemma for the holomorphic function belonging to $\mathcal{N}$(${\alpha}$) is investigated. For the function $f(z)=z+c_2z^2+C_3z^3+{\cdots}$ which is defined in the unit disc where $f(z){\in}\mathcal{N}({\alpha})$, we estimate the modulus of the angular derivative of the function f(z) at the boundary point b with $f(b)={\frac{1}{b}}\int\limits_0^b$ f(t)dt. The sharpness of these inequalities is also proved.

• 충청수학회지
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• 제26권2호
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• pp.357-365
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• 2013

Fix $n-2$ elements $h_1,{\cdots},h_{n-2}$ of the quotient field B of the polynomial algebra $\mathbb{C}[x_1,x_2,{\cdots},x_n]$. It is proved that B is a Poisson algebra with Poisson bracket defined by $\{f,g\}=det(Jac(f,g,h_1,{\cdots},h_{n-2})$ for any $f,g{\in}B$, where det(Jac) is the determinant of a Jacobian matrix.

• 한국농촌건축학회논문집
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• 제26권2호
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• pp.17-25
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• 2024

This study is to use B.F. certification standards to identify the application and differences of B.F. facilities according to various approaches, and to use the analysis results as basic data for the expansion and renovation of new facilities, the National University (Jeonnam University Library), which underwent remodeling before the implementation of the certification system, and the two newly established private universities (Joseon University Library) that were subject to legal application before the implementation of the certification system. First, Chosun University met more B.F. certification standards than Chonnam National University, and mainly intermediary facilities belonged to the best to the best. Second, Chosun University and Chonnam National University's internal facilities met many B.F. certification standards, and Chonnam National University had many areas to improve and found areas to remodel. Third, information facilities at Chonnam National University and Chosun University only had facilities for the hearing impaired, and there were no information facilities for the visually impaired. Facilities for the visually impaired had to be installed, and compared to Chosun University, Chonnam National University fell short of the B.F. certification standard, so there were many areas that needed to be remodeled.

• 충청수학회지
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• 제26권3호
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• pp.625-630
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• 2013

In this paper, we define an extension $f^*:[a,b]{\rightarrow}\mathbb{R}$ of a function $f^*:[a,b]_{\mathbb{T}}{\rightarrow}\mathbb{R}$ for a time scale $\mathbb{T}$ and show that $f$ is Henstock delta integrable on $[a,b]_{\mathbb{T}}$ if and only if $f^*$ is Henstock integrable on $[a, b]$.

• 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.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제26권4호
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• pp.247-254
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• 2019

In this paper, we investigate Hyers-Ulam-Rassias stability of the functional equation f(x + ky) - k²f(x + y) + 2(k² - 1)f(x) - k²f(x - y) + f(x - ky) - k²(k² - 1)(f(y) + f(-y)) = 0, where k is a fixed real number with |k| ≠ 0, 1.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제26권1호
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• pp.49-58
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• 2019

In this paper, I prove the stability problem for a quadratic-cubic functional equation $$f(x+ky)-k^2f(x+y)-k^2f(x-y)+f(x-ky)+f(kx)-{\frac{k^3-3k^2+4}{2}}f(x)+{\frac{k^3-k^2}{2}}f(-x)=0$$ in modular spaces by applying the direct method.

• 대한가정학회지
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• 제26권2호
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• pp.1-13
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• 1988

The purpose of this study was to classify somatotype of males, to show changes of the body skin surface by the somatotype. The size of sample was 156 males between age 20 and 24. Somatotype classified into Bending somatotype, Standard somatotype, Turning over somatotype. And according to the somatotype, changing of the upper part of the body by the arm movements analyzed through gypsum experiment. The result obtained from this study were as follows; 1. the variation of the upper part of the body form by changing the am movements, by the increasing of movements, shoulder-point ws moved to be inside or upside, the anterior armpit point & armpit point were moved to the upside. 2. As a result of investigating into the rate of the expansion and contraction of the basic lines and body surface area by the arm movements, the rate of expansion and contraction of the basic lines by the arm movements, the side sea length showed the maximum rate of extension in 135 degrees, the shoulder length showed the maximum rate of contraction in 135 degrees. The rate of expansion and contraction on the body surface area by the arm movements showed the phenomenon of contraction, of items F1, F6, B1, B9 showed the phenomenon of extension, of items F3, F4, F8, F9, B8, B9. 3. According to somatotypes, items which show the significant difference were, of items f3, f8, b3, b8, F2, F7, F8, B3, B7, in all movements.

• 한국광학회지
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• 제6권3호
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• pp.201-213
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• 1995

전자빔여기 XeF$(C\rightarrowA$ 엑시며 레이저의 상준위 B-와 C-상태에 대하여 충동혼합 운동과정을 포함하는 모델을 컴퓨터 시뮬레이션하여 이의 출력특성을 해석하였다 $XeF^*(B)$ 의 수밀도에 관련되는 $XeF^*(C)$의 형성에 대하여 레이저 에너지를 실험치와 비교하였다. 이 결과는 70ns[FWHM]의 전자빔(800kV, 21kA)을 사용한 대기압 매질에서 매우 좋은 일치$(28.5 mJ\pm5%)$를 보였고, $Xe/F_2/Ar=5.26/0.49/94.28%$의 최적화된 가스혼합비를 확인하였다. 또한 시뮬레이션으로 $XeF^*(C)$의 형성경로, $XeF^*(C)$의 완화경로, 청록색 파장대역의 흡수경로에 대한 $F_2$ 할로겐 도우너 및 Xe 압력의 함수관계를 조사하였다.