• 대한수학회보
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• 제50권2호
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• pp.389-398
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• 2013

Let R be a ring and $\mathcal{Q}$ be a quiver. In this paper we give another definition of purity in the category of quiver representations. Under such definition we prove that the class of all pure injective representations of $\mathcal{Q}$ by R-modules is preenveloping. In case $\mathcal{Q}$ is a left rooted semi-co-barren quiver and R is left Noetherian, we show that every cotorsion flat representation of $\mathcal{Q}$ is pure injective. If, furthermore, R is $n$-perfect and $\mathcal{F}$ is a flat representation $\mathcal{Q}$, then the pure injective dimension of $\mathcal{F}$ is at most $n$.

• 대한수학회지
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• 제43권5호
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• pp.1065-1080
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• 2006

For 3-dimensional Bieberbach groups, we study the de-formation spaces in the group of isometries of $R^3$. First we calculate the discrete representation spaces and the automorphism groups. Then for each of these Bieberbach groups, we give complete descriptions of $Teichm\ddot{u}ller$ spaces, Chabauty spaces, and moduli spaces.

• 건축역사연구
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• 제15권4호
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• pp.37-56
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• 2006

Introducing International Style, P. Johnson and H. R. Hitchcock gave three standards to be the Modern, volume and surface, regularity, and exclusion of applied decoration. In spite of the negation of stylistic, formal approach in the Modernist Manifestoes, one usually have understood Modernity in Architecture with its formal character, especially with no ornament and flat, abstract, white surface. Modernism as a new paradigm in architecture have emphasized that there is no representation of anything outside and only present architecture in itself. They said that Modernism only cared about the language of Architecture without figural reference. So apparently there is no way to prove to its Modernity with formal condition. Modernity is in Spirit and contents. But actually we understand well its existence by visual communication This study deals with this difficult situation how Modernity represents itself without visual media and asks the question how simultaneously it presents its thingness and materiality In order to analyse contradictory situation between representation and presentation in Modern Architecture we need to survey the historical process of changing position of ornaments and its meaning in time. With the crisis of representation the role of ornament have seriously changed and divided. It caused the two situation in pre-Modern Architecture. Firstly, Architecture tend to be a high art and formal expression became important much more. The Use of Ornament became a kind of fashion to show the power, class, money. Secondly, Ornament lost its cultural weight and the structure and material aspect became the central in architecture. Rational Structuralism would be the essential character in Modern Architecture. Here the theory of G. Semper and A. Loos on cladding(dressing) and Ornament can help its problems and limits. In the situation without conventional ornament Modernists need to present modernity with new media that only show the thing itself and by that it does not represent any thing else as like the value, idea outside buildings. They believed that only it concerned esthetics and morality in architecture. But in reality it referred to art and machines as like ships, aircraft, and cars. By excluding Ornament and showing the process of clearing, abstract, flat, white surface 'represent' Modernity by the indirect way referring the concept of transparency, reason, sanitation, tectonics, etc. An Ideology and myth intervened architectural discourse to make the doxa about the representation in Architecture. Surface must be a different kind of media and message that can communicate in different way with compared to conventional Ornament. Decorated Shed by R. Venturi and Post-Functionalism by P. Eisenman, that are the most famous post-modern discourse, shows well difficult and contradictory condition in contemporary architecture concerning representation and form, meaning and form.

• Journal of the Optical Society of Korea
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• 제10권4호
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• pp.162-168
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• 2006

The variation of global coherence on propagation plane by plane is examined in the framework of coherent mode representation. It is explained through concrete examples that the global coherence may in general be enhanced, may be reduced, or may not change. When the mode functions form a complete set and the corresponding eigenvalues are in nitely degenerate, there necessarily develops a certain amount of global coherence on propagation, which is the essence of van Cittert-Zernike theorem. The propagation generates a certain pattern of the eigenvalue spectrum from the initial flat one and this is shown to be related to the non-unitarity of the propagation kernel.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.548-550
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• 2010

The droplet motion on a flat substrate with contact angle hysteresis is studied by solving the equations governing the conservation of mass and momentum. The liquid- gas interface is determined by an level-set method which is based on a sharp-interface representation for accurately imposing the matching or coupling conditions at the interface. The method is modified to treat the dynamic contact angle at the liquid-gas-solid interface. The computations are performed to investigate a droplet impact and merging pattern on a flat substrate to find a optimal condition in a micro-line patterning process. The effects of dynamic contact angles on droplet motion are quantified.

• 대한전자공학회논문지
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• 제25권8호
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• pp.1010-1018
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• 1988

This paper proposes a MOS circuit extractor which extracts a netlist from the hierarchical mask information, for the verification tools. To utilize the regularity and the simple representation of the hierarchical circuit, and to reduce the debug cycle of design, verification, and modification, we propose a hierarvhical and incremental circuit extraction algorithm. In flat circuit extraction stage, the multiple storage quad tree is used as an internal data structure. Incremental circuit extraction using the hierarchical structure is made possible, to reduce the re-extraction time of the modified circuit.

• 대한수학회지
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• 제51권6호
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• pp.1177-1187
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• 2014

In the current paper we study absolutely pure representations of quivers. Then over some nice quivers including linear quivers some sufficient conditions guaranteeing a representation to be absolutely pure is characterized. Furthermore some relations between atness and absolute purity is investigated. Finally it is shown that the absolutely pure covering of representations of linear quivers (including $A^-_{\infty}$, $A^+_{\infty}$ and $A^{\infty}_{\infty}$) by R-modules whenever R is a coherent ring exists.

• 한국보육지원학회지
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• 제11권1호
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• pp.153-171
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• 2015

본 연구는 유아의 내적표상 유형에 따라 가정에서의 코티솔 분비 패턴이 어떠한지를 탐색해보고자 하였다. 이를 위해 40명의 유아를 대상으로 이야기 완성과제(MacArthur Story Stem Battery, Breth erton et al. 1990)를 실시하였고, 가정에서 유아의 타액을 채취하여 수집하였다. 수집된 자료는 기술통계, 군집분석을 통해 분석하였다. 분석결과 유아의 내적표상 유형은 불안유형, 제한유형, 비조절된 공격유형, 회피유형, 친사회유형의 5개 유형으로 나타났으며, 유아의 가정에서의 코티솔 분비 패턴은 오전에 코티솔 분비가 많고 오후로 갈수록 떨어지는 패턴으로 나타났다. 또한 내적표상 유형에 따라 분비패턴이 다르게 나타났다. 이러한 결과를 통해 볼 때 유아의 내적 표상이 일상적 스트레스 상황과 부모와의 상호작용시에 유아의 반응과 스트레스 호르몬의 활성화 정도에 영향을 미칠 가능성이 있음을 조심스레 예측할 수 있다.

• Physical Therapy Rehabilitation Science
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• 제4권2호
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• pp.87-93
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• 2015

Objective: Balance is a preceding task for functional activities in daily activities as well as community-dwelling activities. To learn skilled and functional activities, it is also necessary to imagine an appropriate and effective movement representation used to plan and execute the functional activities. The purpose of this study was to evaluate the effects of balance imagery of semi-tandem stance on a flat floor and balance beam on balance abilities for elderly and young adults. Design: Cross-sectional study. Methods: Fifteen elderly and thirty-four young adults were enrolled in this study. In order to determine whether there is a change in postural control ability according to the different imagery training methods used, standing static balance measurements were performed. According to the therapist's instructions, participants were to stand in a semi-tandem position on the Good Balance System for 1 minute while imagining that they were standing on a balance beam, and while the postural control abilities was assessed. Results: Postural control was significantly different in balance ability of semi-tandem stance on a flat floor compared to on a balance beam in both geriatrics and young adults. Postural sway was more significantly decreased in young adults than older adults during balance imagery of semi-tandem stance on a flat floor as well as on balance beam (p<0.05). Conclusions: The results of this study suggest that the ability to mentally represent their actions was similar in older adults compared to young adults, although older adults showed a drop in efficiency of postural control more than young adults.

• 건축역사연구
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• 제21권4호
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• pp.7-24
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• 2012

The Buddhist cave temple carved into the rock provides a large space for the ritual in general in which a structure of Stupa is built in the center of the space purely for religious worship empty of Sarira, and the temple is formed around this Stupa. Relief-Stupa of the cave temple indicates the similar shape that of Relief-religious worship of flat land temple. However, there appears a small difference in representation since the background of formation of the cave temple differs in that of flat land temple. Specially, Caitya Stupa of currently existing cave temples have been damaged to lose of their original shape only possible to be analyzed the stylistic development through Relief-Stupa from which the characteristic of Stupa could be understood. The early cave temple could be characterized with a balanced structure consists of upturn bowl, steeple stone with simple drum & Hamikawasnagae, in which it appears strongly the detail factor characteristics of drum & steeple of having system with Caitya Stupa. In the post cave temple, the subject of worship moved to statue of Buddha due to the influence of Gandhara, Mathura art which reduced the importance of Stupa. This illustrates in Relief-stupa as well the style change as well as changes in detail factor. The sculpture appeared at the limited location either the wall of Caitya shrine or pillar in vihara cave with stronger decorative meaning. Contrast to the Relief Stupa of early flat land temples or the cave temples mentioned above sculptured with symbolism, however, the post cave temple showed the relief structure based on the plan of flat plan.