• 대한수학회지
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• 제58권2호
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• pp.487-499
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• 2021

We prove a decay estimate for oscillatory integrals with Hölder amplitudes and polynomial phases. The estimate allows us to answer certain questions concerning the uniform boundedness of oscillatory singular integrals on various spaces.

• 정보보호학회논문지
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• 제1권1호
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• pp.97-101
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• 1991

다항식 인수분해 문제는 정수론에서 뿐만 아니라 Discrete logarithm과 관련하여 암호학의 응용에도 중요한 문제이다. Hensel의 Lifting Lemma를 이용하여 유한체위에서 다항식을 인수분해하여 정수계수위에서 다항식의 인수를 찾는 방법으로 정수계수위에서 다항식의 인수분해를 실행하였다.

• 대한수학회보
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• 제59권6호
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• pp.1423-1438
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• 2022

In this paper, we study a special exhaustion function on almost Hermitian manifolds and establish the existence result by using the Hessian comparison theorem. From the viewpoint of the exhaustion function, we establish a related Schwarz type lemma for almost holomorphic maps between two almost Hermitian manifolds. As corollaries, we deduce several versions of Schwarz and Liouville type theorems for almost holomorphic maps.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제29권1호
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• pp.113-124
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• 2022

In this paper, we plan to introduce the class of the analytic functions called 𝒫 (b) and to investigate the various properties of the functions belonging this class. The modulus of the second coefficient c₂ in the expansion of f(z) = z+c₂z²+… belonging to the given class will be estimated from above. Also, we estimate a modulus of the second angular derivative of f(z) function at the boundary point 𝛼 with f'(𝛼) = 1 - b, b ∈ ℂ, by taking into account their first nonzero two Maclaurin coefficients.

• 대한수학회논문집
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• 제38권2호
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• pp.389-400
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• 2023

In this paper, some estimations will be given for the analytic functions belonging to the class 𝓡(α). In these estimations, an upper bound and a lower bound will be determined for the first coefficient of the expansion of the analytic function h(z) and the modulus of the angular derivative of the function ${\frac{zh^{\prime}(z)}{h(z)}}$, respectively. Also, the relationship between the coefficients of the analytical function h(z) and the derivative mentioned above will be shown.

• Korean Journal of Mathematics
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• 제31권1호
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• pp.25-33
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• 2023

This paper's objectives are to present the $\mathcal{H}$ class of analytical functions and explore the many characteristics of the functions that belong to this class. Some inequalities regarding the angular derivative have been discovered for the functions in this class. In addition, the symmetry points on the unit disc are used for the obtained inequalities.

• 한국작물학회지
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• 제27권1호
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• pp.49-54
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• 1982

보리의 생리적 성숙기를 외시적 형질의 변이로서 판정할 수 있는 기준을 설정하여 효과적인 단기 등숙성 계통선발과 등숙유전 연구에 활용하고저 33 품종 및 계통을 4 출수군으로 분류하여 5개 형질에 대하여 검토하였다. 그 결과를 요약하면 다음과 같다. 1. 조기출수 품종일수록 등숙기간이 길어져 출수기와 등숙기간에는 고도의 부의 상관(r=0.656$^{**}$ )를 보였고, 품종간 등숙기간의 차이가 인정되었다. 2. 성숙기 결정에 이용된 각형질중 수분함량과 외영의 색도변화가 가장 유효하였다. 3. 생리적 성숙기를 외시적 측정에 의하여 결정할 때 외영의 색도가 가장 안정하고 민감하게 변화하여 유용한 형질이었다. 또한 지엽의 색도변화를 같이 고려한다면 더 정확한 숙기판단이 될 것으로 본다. 4. 이 시기에 외영의 색은 Grayish yellow (연회황색)이었고, 평균 수분함량은 약 33%이었다.

• Plant Resources
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• 제5권2호
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• pp.95-103
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• 2002

Microscopic techniques were used to observe the microstructure of rice husk. Microscopic examination showed that two main components of husk, lemma and palea consisted of outer epidermis, layers of fibers, vascular bundles, parenchyma cells, and inner epidermis, in sequence from the outer to the inner surface. The outer epidermal walls were extremely thick, highly convoluted and lignified. The underlying fibers were also thick-walled and lignified. Parenchyma cells were thin-walled and unlignified. Inner epidermal cells were also unlignified. The outer surface of both lemma and palea were conspicuously ridged, but the lower surface had a flat appearance. As part of a detailed study to characterize rice husk using microscopic and micro-analytical techniques, distribution of silica was also examined, and is presented elsewhere. Rice husk can potentially be used as a raw material for making composite products and the observations presented here form valuable background information for our future work related to product development.

• 대한수학회보
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• 제53권2호
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• pp.325-334
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• 2016

In this paper, a boundary version of the Schwarz lemma is investigated. We take into consideration a function $f(z)=z+c_{p+1}z^{p+1}+c_{p+2}z^{p+2}+{\cdots}$ holomorphic in the unit disc and $\|\frac{f(z)}{{\lambda}f(z)+(1-{\lambda})z}-{\alpha}\|$ < ${\alpha}$ for ${\mid}z{\mid}$ < 1, where $\frac{1}{2}$ < ${\alpha}$ ${\leq}{\frac{1}{1+{\lambda}}}$, $0{\leq}{\lambda}$ < 1. If we know the second and the third coefficient in the expansion of the function $f(z)=z+c_{p+1}z^{p+1}+c_{p+2}z^{p+2}+{\cdots}$, then we can obtain more general results on the angular derivatives of certain holomorphic function on the unit disc at boundary by taking into account $c_{p+1}$, $c_{p+2}$ and zeros of f(z) - z. We obtain a sharp lower bound of ${\mid}f^{\prime}(b){\mid}$ at the point b, where ${\mid}b{\mid}=1$.

• East Asian mathematical journal
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• 제10권2호
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• pp.339-343
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• 1994