• Bulletin of the Korean Mathematical Society
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• v.25 no.2
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• pp.243-246
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• 1988

Let M(z)=exp (-1+z/1-z) be the unit singular inner function. See [1] or [2] for the basic facts about inner functions. We define the iterations of M9z) as (Fig.) Since the composition M$_{2}$(z)=M.M(z) is known (see [5] for example) to be singular inner function it has the "cannonical" representation (Fig.) where .mu. is a finite, positive singular Borel measure on the unit circle T. In section 2, we have explicit cannonical representation of M$_{2}$(z) by determining the singular measure .mu. In section 3 we show that (Fig.) These facts might have been known but could not be found in the literature.iterature.

• Journal of the Korean Mathematical Society
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• v.48 no.2
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• pp.397-420
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• 2011

In this paper we study the structure of closed weakly dense ideals in Privalov spaces $N^p$ (1 < p < $\infty$) of holomorphic functions on the disk $\mathbb{D}$ : |z| < 1. The space $N^p$ with the topology given by Stoll's metric [21] becomes an F-algebra. N. Mochizuki [16] proved that a closed ideal in $N^p$ is a principal ideal generated by an inner function. Consequently, a closed subspace E of $N^p$ is invariant under multiplication by z if and only if it has the form $IN^p$ for some inner function I. We prove that if $\cal{M}$ is a closed ideal in $N^p$ that is dense in the weak topology of $N^p$, then $\cal{M}$ is generated by a singular inner function. On the other hand, if $S_{\mu}$ is a singular inner function whose associated singular measure $\mu$ has the modulus of continuity $O(t^{(p-1)/p})$, then we prove that the ideal $S_{\mu}N^p$ is weakly dense in $N^p$. Consequently, for such singular inner function $S_{\mu}$, the quotient space $N^p/S_{\mu}N^p$ is an F-space with trivial dual, and hence $N^p$ does not have the separation property.

• Journal of the Korean Mathematical Society
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• v.33 no.1
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• pp.39-46
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• 1996

Let $\alpha > 0$ and $\zeta$ be a point on the unit circle $T= {$\mid$z$\mid$ = 1}$ of the complex plane C.

• Journal of the Korean Mathematical Society
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• v.36 no.4
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• pp.787-811
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• 1999

Let M be the maximal ideal space of the Banach algebra $H^{\infty}$ of bounded analytic functions on the open unit disc $\triangle$. For a positive singular measure ${\mu}\;on\;{\partial\triangle},\;let\;{L_{+}}^1(\mu)$ be the set of measures v with $0\;{\leq}\;{\nu}\;{\ll}\;{\mu}\;and\;{{\psi}_{\nu}}$ the associated singular inner functions. Let $R(\mu)\;and\;R_0(\mu)$ be the union sets of $\{$\mid$\psiv$\mid$\;<\;1\}\;and\;\{$\mid${\psi}_{\nu}$\mid$\;<\;0\}\;in\;M\;{\setminus}\;{\triangle},\;{\nu}\;\in\;{L_{+}}^1(\mu)$, respectively. It is proved that if $S(\mu)\;=\;{\partial\triangle}$, where $S(\mu)$ is the closed support set of $\mu$, then $R(\mu)\;=\;R0(\mu)\;=\;M{\setminus}({\triangle}\;{\cup}\;M(L^{\infty}(\partial\triangle)))$ is generated by $H^{\infty}\;and\;\overline{\psi_{\nu}},\;{\nu}\;{\in}\;{L_1}^{+}(\mu)$. It is proved that %d{\theta}(S(\mu))\;=\;0$ if and only if there exists as Blaschke product b with zeros $\{Zn\}_n$ such that $R(\mu)\;{\subset}\;{$\mid$b$\mid$\;<\;1}\;and\;S(\mu)$ coincides with the set of cluster points of $\{Zn\}_n$. While, we proved that $\mu$ is a sum of finitely many point measure such that $R(\mu)\;{\subset}\;\{$\mid${\psi}_{\lambda}$\mid$\;<\;1}\;and\;S(\lambda)\;=\;S(\mu)$. Also it is studied conditions on \mu for which $R(\mu)\;=\;R0(\mu)$.

• Journal of Science of Art and Design
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• v.4
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• pp.67-90
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• 2002

What is the semantic function of visual image in Contemporary art? This article proposes that representation is semantically still important in post-modernism as well as in modernism. The semantic function of representation has been changed by keeping pace with times. In modernism the 'outer representation' changed to 'inner representation', and in postmodernism the 'inner representation' changed to 'metaphorical representation'. The 'outer representation' means that image indicates a certain object or subject as the classical realism. In this case, the meaning of image is subordinate to an object, and a one-to-one correspond existed between the image and the object. Because this 'outer representation' is focused on an object but subject's intention, the indicative function of meaning is definite and singular. The 'inner representation' means that image exposes the fundamentals or process of an object. In this case, the meaning of image resolves itself into an absolute fundamental, and one-to-many correspond existed between the image and the object. Because this 'inner representation' is focused on essence and substance but an external form, the indicative function of meaning is inclusive and general. The 'metaphorical representation' means that image critically relates social constraint and condition as metaphor and allegory. In this case, the meaning of image is not subordinate to an object and a subject, and the image and the object indicate interactively. Because this 'metaphorical representation' is focused on interaction between subject, object, and interpreter, the indicative function of meaning is differant and ecological. This article focused on the representation because I believe that continuous thinking of totality can be opened by cognitive mapping, even though we never understand the world totally in the chaotic post modern age.

• Journal of Welding and Joining
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• v.29 no.2
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• pp.64-71
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• 2011

In this paper, crack propagation analyses in the inner diameter (ID) repair weld of the dissimilar metal weldment of a nozzle were performed using a finite element alternating method (FEAM). To calculate the theoretical solution for the crack tip stress intensity factor, a weak type singular integral equation consisted of crack surface traction and dislocation density function was constructed and solved in conjunction with the FEAM. A two-dimensional axisymmetric finite element nozzle model was prepared and ID repair welding was simulated. An initial crack, 10% depth of weld thickness, was assumed and crack propagation trajectory from the initial crack to the 75% depth of thickness was calculated using the FEAM. Crack growth versus time curve was also calculated and compared with the curves obtained from ASME code method. With the method constructed in this paper, crack propagation trajectory and crack growth time were calculated automatically and effectively.

• Journal of The Korean Association For Science Education
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• v.34 no.2
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• pp.55-62
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• 2014

This study is to reclassify the classifications or definitions of scientific literacy in scientific literacy researches since 1960s and grasp the classification trends of scientific literacy definitions. Sixteen articles have been selected among the articles that have been introduced in the two articles. Classification criteria are as follows: 1) "be learned," "competence," or "be able to function in society" as meanings of "literate," 2) "terms" or "description" as the ways of representing scientific literacy, 3) "singular structure," "hierarchical structure," or "parallel structure" as the inner structure of scientific literacy definitions. The results of this study are as follows: First, hierarchical structures in scientific literacy have almost always accompanied "terms" representing scientific literacy and also accepted the hierarchy between "be learned" and "competence," but not the definition of scientific literacy as functioning in society. All parallel structures in scientific literacy have accompanied the definition as functioning in society. And singular structure almost always appears in researches based on the views of scientific literacy in relatively recent times. Second, researches who have used "terms" as ways of representing scientific literacy have increased. Based on the results in this study, the meanings of scientific literacy have been emphasized in view of the ability of playing a role in a social context as well as learning and competence these days. To meet this movement in scientific literacy actively, science education community should get out of traditional teaching and learning scientific concepts and give emphasis on application in various context and social role of science learners.