• 대한수학회논문집
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• 제20권1호
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• pp.63-70
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• 2005

In this paper we study bounded and compact weighted composition operator, induced by a fixed analytic function and an analytic self-map of the open unit disk, from Bergman space into weighted Bloch space. As a corollary, obtain the characterization of composition operator from Bergman space into weighted Bloch space.

• 대한수학회보
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• 제50권1호
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• pp.185-200
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• 2013

We study the bounded and the compact weighted composition operators from the Hardy space $H^{\infty}$ into BMOA and into VMOA, from BMOA into $H^{\infty}$, as well as from BMOA into the Bloch space. We also provide new boundedness and compactness criteria for the weighted composition operators on BMOA and on VMOA.

• 대한수학회지
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• 제45권4호
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• pp.977-991
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• 2008

We characterize the boundedness and compactness of the weighted composition operator $uC_{\psi}$ from the general function space F(p, q, s) into the logarithmic Bloch space ${\beta}_L$ on the unit disk. Some necessary and sufficient conditions are given for which $uC_{\psi}$ is a bounded or a compact operator from F(p,q,s), $F_0$(p,q,s) into ${\beta}_L$, ${\beta}_L^0$ respectively.

• 대한수학회논문집
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• 제20권4호
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• pp.703-708
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• 2005

Let ${\varphi}(z)\;=\;({\varphi}_1(Z),{\cdots},{\varphi}_n(Z))$ be a holomorphic self­map of $\mathbb{D}^n$, where $\mathbb{D}^n$ is the unit polydisk of $\mathbb{C}^n$. The sufficient and necessary conditions for a composition operator to be bounded and compact from the Hardy space $H^2(\mathbb{D}^n)$ into $\alpha$-Bloch space $\beta^{\alpha}(\mathbb{D}^n)$ on the polydisk are given.

• 대한수학회지
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• 제45권5호
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• pp.1203-1220
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• 2008

Let V be an arbitrary system of weights on an open connected subset G of ${\mathbb{C}}^N(N{\geq}1)$ and let B (E) be the Banach algebra of all bounded linear operators on a Banach space E. Let $HV_b$ (G, E) and $HV_0$ (G, E) be the weighted locally convex spaces of vector-valued analytic functions. In this paper, we characterize self-analytic mappings ${\phi}:G{\rightarrow}G$ and operator-valued analytic mappings ${\Psi}:G{\rightarrow}B(E)$ which generate weighted composition operators and invertible weighted composition operators on the spaces $HV_b$ (G, E) and $HV_0$ (G, E) for different systems of weights V on G. Also, we obtained compact weighted composition operators on these spaces for some nice classes of weights.

• Kyungpook Mathematical Journal
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• 제55권2호
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• pp.345-353
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• 2015

Subnormality of bounded weighted composition operators on $L^2({\Sigma})$ of the form $Wf=uf{\circ}T$, where T is a nonsingular measurable transformation on the underlying space X of a ${\sigma}$-finite measure space (X, ${\Sigma}$, ${\mu}$) and u is a weight function on X; is studied. The standard moment sequence characterizations of subnormality of weighted composition operators are given. It is shown that weighted composition operators are subnormal if and only if $\{J_n(x)\}^{+{\infty}}_{n=0}$ is a moment sequence for almost every $x{{\in}}X$, where $J_n=h_nE_n({\mid}u{\mid}^2){\circ}T^{-n}$, $h_n=d{\mu}{\circ}T^{-n}/d{\mu}$ and $E_n$ is the conditional expectation operator with respect to $T^{-n}{\Sigma}$.

• Applied Biological Chemistry
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• 제45권3호
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• pp.162-167
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• 2002

밤 삽피의 천연 항산화제로서의 이용 가능성을 검토하기 위하여 밤 삽피로부터 유리형(EPA), 에스데르형(EPA), 결합형(BPA) 페놀산 획분을 분리하였다. 각 획분의 수율은 유리형 0.794%, 에스테르형 1.236%,결합형이 1.937%였으며 이중 페놀성 화합물의 함량은 에스테르형이 65.19%로 가장 높았다. Gas chromatography로 각 획분의 페놀산의 조성과 함량을 조사한 결과 유리형 획분에서 gallic acid(4.63%), ellagic acid(3.49%), salicylic acid(3.19%), gentisic acid(1.5%)가, 에스테르형 획분에서 gallic acid(13.4%), ellagic acid(11.6), protocatechuic acid(0.9%)가 주요 페놀산으로 확인 되었으며,결합형 획분에서는 gallic acid는 확인되지 않고 다른 획분에 비하여 sinapic acid(1.33%)가 높은 함량을 보였다. 이들 획분의 항산화성을 DPPH 라디칼 소거능, hydroxyl radical 소거능, 지질과산화물 생성 억제 시험으로 조사한 결과 유리형, 에스데르형, 결합형 획분의 순으로 항산화 활성이 우수한 것으로 조사되었다.

• 대한수학회지
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• 제54권2호
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• pp.599-612
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• 2017

If ${\psi}$ is analytic on the open unit disk $\mathbb{D}$ and ${\varphi}$ is an analytic self-map of $\mathbb{D}$, the weighted composition operator $C_{{\psi},{\varphi}}$ is defined by $C_{{\psi},{\varphi}}f(z)={\psi}(z)f({\varphi}(z))$, when f is analytic on $\mathbb{D}$. In this paper, we study normal, cohyponormal, hyponormal and normaloid weighted composition operators on the Hardy and weighted Bergman spaces. First, for some weighted Hardy spaces $H^2({\beta})$, we prove that if $C_{{\psi},{\varphi}}$ is cohyponormal on $H^2({\beta})$, then ${\psi}$ never vanishes on $\mathbb{D}$ and ${\varphi}$ is univalent, when ${\psi}{\not\equiv}0$ and ${\varphi}$ is not a constant function. Moreover, for ${\psi}=K_a$, where |a| < 1, we investigate normal, cohyponormal and hyponormal weighted composition operators $C_{{\psi},{\varphi}}$. After that, for ${\varphi}$ which is a hyperbolic or parabolic automorphism, we characterize all normal weighted composition operators $C_{{\psi},{\varphi}}$, when ${\psi}{\not\equiv}0$ and ${\psi}$ is analytic on $\bar{\mathbb{D}}$. Finally, we find all normal weighted composition operators which are bounded below.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1041-1046
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• 1998

This study was carried out to investigate the changes and composition of the non-cellulosic neutral sugars in cell wall of soybean sprouts during growth. The composition of non-cellulosic neutral sugars in cell of soybean sprouts was rhamnose, fucose, xylose, arabinose, mannose, galactose and glucose. The galactose content of cell wall was higher than other non-cellulosic neutral sugars, and was remarkably decreased during growth. The major non-cellulosic sugars of pectic substances were rhamnose, arabinose, and galactose. The arabinose content of pectic substance was increased in cotyledon and hypocotyl during growth. The contents of non-cellulosic neutral sugars were decreased in hypocotyl during growth. The galactose content of pectic substance was higher in cotyledon than those in hypocotyl, and was increased in cotyledon. The content of rhamnose was higher in ionically associated pectic substance than that in covalently bounded pectic substance. The major non-cellulosic neutral sugars of hemicellulose were glucose, rhamnose, arabinose and galactose. The galactose of hemicellulose was decreased remarkably during growth.

• 한국식품영양과학회지
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• 제15권2호
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• pp.165-170
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• 1986

고추 과실의 연화와 관련된 세포벽 다당류의 변화를 조사하기 위하여 조세포벽으로부터 화학적인 방법에 의하여 IAP(ionically associated pectin), CBP(covalently bounded pectin), HF(hemicellulosic fraction) 및 CF(cellulosic fraction) 등의 다당류를 분획하여 그 조성변화를 살펴보았다. 고추 과실 세포벽 구성 IAP와 CBP는 $4{\sim}29%$의 hemicellulose와 $0.9{\sim}2.1%$의 cellulose를 함유하였으며, HF는 $8{\sim}13%$의 pectin과 $0.1{\sim}1.1%$의 cellulose를 함유하였다. 또 IAP와 CBP를 구성하는 polyuronide는 IAP쪽이 높았으나, hemicellulose는 CBP쪽이 높았다. CF를 제외한 모든 다당류는 turning stage 이후에 감소하였다. IAP와 CBP의 구성 polyuronide는 IAP에서는 큰 변화를 보이지 않았으나, CBP에서는 증가하였는데, 이것은 CBP와 결합한 HF의 감소에 기인하며, 이 감소의 주된 원인은 구성 galactose의 손실에 의한 것으로 판단되었다.