• Journal of Korean Society of Rural Planning
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• v.4 no.1
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• pp.15-21
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• 1998

The purpose of the study is to identify a basic spatial unit for rural village redevelopment plan. An ideal spatial unit need to satisfy three basic premises: to be homogeneous as rural community, to be appropriate to implement the project, and to be compatible with regional planning systems. A spatial unit could, empirically, be defined based on the homogeneity at first, and then appropriateness and compatibility could be used to adjust its boundary. Mitan-Myun(13 villages), Pyungchang County, Dochuck-Myun(15 villages), Kwangju County, and Chuksan-Myun(28 villages), Kimje City in Korea were selected as case study areas. The degree of interrelationship between all possible pairs in each Myun was measured using spatial, socio-cultural, and economic indicators. Multidimensional Scaling(MDS) was used to identify a homogeneous spatial unit, and then indicators representing appropriateness and compatibility were used to adjust the identified boundary. New districts which have two or three villages were suggested as a reasonable spatial unit for rural village redevelopment, and its boundary roughly overlaps with Bup-Jeong-Ri(法定里: a legally defined village).

• Structural Engineering and Mechanics
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• v.40 no.5
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• pp.665-688
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• 2011

This paper presents a theoretical analysis for the free vibration of rectangular tanks partially filled with an ideal liquid. Wet dynamic displacements of the tanks are approximated by combining the orthogonal polynomials satisfying the boundary conditions, since the rectangular tanks are composed of four rectangular plates. The classical boundary conditions of the tanks at the top and bottom ends are considered, such as clamped, simply supported, and clamped-free boundary conditions. As the facing rectangular plates are assumed to be geometrically and structurally identical, the vibration modes of the facing plates of the tanks can be divided into two categories: symmetric and antisymmetric modes with respect to the planes passing through the center of the tanks and perpendicular to the free liquid surface. The liquid displacement potentials satisfying the Laplace equation and liquid boundary conditions are derived, and the wet dynamic modal functions of a quarter of the tanks can be expanded by the finite Fourier transform for compatibility requirements along the contacting surfaces between the tanks and liquid. An eigenvalue problem is derived using the Rayleigh-Ritz method. Consequently, the wet natural frequencies of the rectangular tanks can be extracted. The proposed analytical method is verified by observing an excellent agreement with three-dimensional finite element analysis results. The effects of the liquid level and boundary condition at the top and bottom edges are investigated.

• Coupled systems mechanics
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• v.12 no.2
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• pp.127-149
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• 2023

A theoretical method is developed to analyze the free vibration of an elastic annular plate in contact with an ideal liquid. The displacement potential functions of the contained liquid are expressed as a combination of the Bessel functions that satisfy the Laplace equation and the liquid boundary conditions. The compatibility condition along the interface between the annular plate and the contained liquid is taken into account to consider the fluid-structure coupling. The dynamic displacement of the wet annular plate is assumed to be a combination of dry eigenfunctions, allowing for prediction of the natural frequencies using the Rayleigh-Ritz method. The study investigates the effect of radial liquid boundary conditions on the natural frequencies of the wet annular plate, considering four types of liquid bounding: outer container bounded, outer and inner bounded, inner bounded, and radially unbounded. The proposed theoretical method is validated by comparing the predicted wet natural frequencies with those obtained from finite element analysis, showing excellent accuracy. The results indicate that the radial liquid bounding effect on the natural frequencies is negligible for the axisymmetric vibrational mode, but relatively significant for the mode with one nodal diameter (n =1) and no nodal circle (m' = 0). Furthermore, the study reveals that the wet natural frequencies are the largest for the plate with an inner bounded cylinder among the radial liquid boundary cases, regardless of the vibration mode.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.461-469
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• 2021

Houses contain our own characteristics and philosophy. As a Yangban house in the late Joseon Dynasty, the house of Kwon Hee-moon was constructed over 250 years to the present. Therefore, this house can more objectively examine the aesthetic ideals, such as the thoughts and philosophies of the house owners across the generations. The name of Sarang-Chae is Ui-Wang-Seo(嶷汪棲), it shows thoughts and philosophies symbolically. Ui(嶷)·Wang(汪) mean the elements of nature, and Seo(棲) symbolizes living together, It is aesthetics of Nature, aesthetics of Human boundary. Aesthetics of Nature boundary is aesthetics of Ui(嶷)·Wang (汪), so it is clear and fine. Aesthetics of Human boundary is aesthetics of Seo(棲), so it has meditation and purity. As such, the aesthetic ideal of Kwon Hee-moon's house pursues the ideal of life. Through the aesthetic boundary of the house of Kwon Hee-moon, we can understand the aesthetic boundary of Honam Yang-ban House in the Late Chosun Dynasty.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.1
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• pp.68-78
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• 1997

A numerical study on the transient vapor flow and heat transfer is performed to investigate the ideal switching operation of heat source in a high temperature heat pipe. The cylindrical 2-dimensional compressible laminar vapor flow is assumed for the vapor space and the conjugate heat transfer for the heat pipe wall, wick and vapor space is calculated. The different boundary conditions such as constant heat flux, convective or radiative boundary at the outer wall are used respectively to compare the influence of boundary conditions on the transient operation. The transient temperature profile and the internal flow of the entire pipe for the switching operation are described as a result. The results show that the transient time is not significantly affected by the boundary conditions at the outer wall in present study. During the transition, two independent flows are observed temporarily on the right side and left side of the heat pipe. It is also found that the trend of temperature variation in the vapor region is different from the variation in the wick and wall region.

• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.3
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• pp.83-98
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• 2000

유연한 액체 저장탱크 내 유체의 부가질량 및 슬러싱 강성행렬을 도출하는 새로운 방법을 제시하였다. 비점성, 비압축성 이상유체를 표면 출렁임을 고려하여 경계요소법에 의하여 모델링하였다. 유체의 표면과 저장탱크 벽체의 접촉면과 같은 불연속 경계를 다루기 위해 특별한 과정을 도입하였다. 원통형 액체저장탱크의 지진응답해석에 적용하여 우수한 결과를 얻을 수 있음을 확인하였다.

• Journal of the Korean Home Economics Association
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• v.32 no.4
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• pp.149-162
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• 1994

The Purpose of this study is to explore the conceptions and the practices about childreariong in the Koryo Dynasty(918-1392 A, D). The method used for this study is the historical method and the literatures of analysis are the Koryo Dynasty History. According to the results the conceptions of childhood in its boundary were that the point at which childhood ended was the age of 15, which was sud-devided into three of different periods. And the conceptions of childhood in its nature and its ideal traits were that child's ability was determinated innately and intellectual features and mutual understanding of others were emphasized as its ideal traits. Also the practices of childrearing in Koryo Dynasty were that a child was carried on adult's back, and that parents prayed for giving birth to their child and finally that the role expectation toward childrearing was affectionate caring. Moreover there were the child welfare work and the educational system in Koryo Dynasty. Through this study, we can have access to the understanding about cultural transmission process of childrearing in Korea.

• Journal of the Korean Mathematical Society
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• v.56 no.4
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• pp.1131-1158
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• 2019

An ideal right-angled pentagon in hyperbolic 4-space ${\mathbb{H}}^4$ is a sequence of oriented geodesics ($L_1,{\ldots},L_5$) such that $L_i$ intersects $L_{i+1},i=1,{\ldots},4$, perpendicularly in ${\mathbb{H}}^4$ and the initial point of $L_1$ coincides with the endpoint of $L_5$ in the boundary at infinity ${\partial}{\mathbb{H}}^4$. We study the geometry of such pentagons and the various possible augmentations and prove identities for the associated quaternion half side lengths as well as other geometrically defined invariants of the configurations. As applications we look at two-generator groups ${\langle}A,B{\rangle}$ of isometries acting on hyperbolic 4-space such that A is parabolic, while B and AB are loxodromic.

• Journal of the Korean Mathematical Society
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• v.56 no.3
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• pp.595-622
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• 2019

An ideal right-angled pentagon in hyperbolic 4-space ${\mathbb{H}}^4$ is a sequence of oriented geodesics ($L_1,{\ldots},L_5$) such that Li intersects $L_{i+1},\;i=1,\;{\ldots},\;4$, perpendicularly in ${\mathbb{H}}^4$ and the initial point of $L_1$ coincides with the endpoint of $L_5$ in the boundary at infinity ${\partial}{\mathbb{H}}^4$. We study the geometry of such pentagons and the various possible augmentations and prove identities for the associated quaternion half side lengths as well as other geometrically defined invariants of the configurations. As applications we look at two-generator groups ${\langle}A,B{\rangle}$ of isometries acting on hyperbolic 4-space such that A is parabolic, while B and AB are loxodromic.

• Journal of the Society of Naval Architects of Korea
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• v.32 no.1
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• pp.58-69
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• 1995

The present paper is devoted to constructing a numerical algorithm for solving un steady problems on generation, propagation and interaction of nonlinear waves at a surface of ideal fluid, within the framework of the potential-flow model. The numerical scheme is implicit. with non-linearity iteration at every step of time. the finite-difference method with boundary-fitted coordinates are presented in favor for validity and high efficiency of the numerical model developed. Among these arguments, there are the results of calculations of two test problems-on stretching of a liquid ellipse and on wave generation by lifting a portion of a bottom.