• Title, Summary, Keyword: Structure

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Evaluation of Ultimate Pressure Capacity of Wolsong Containment Structure (월성 원자력발전소 격납건물의 극한내압평가)

  • Kwak Hyo-Gyoung;Kim Jae Hong;Kim Sun-Hoon;Chung Yun-Suk
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • pp.183-189
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    • 2005
  • Nuclear containment structure is the last barrier for being secure from any nuclear power plant accident. Even though the safety requirements of nuclear power plant have been focused on removing accidental situations, nuclear containment structure must reserve the sufficient resisting capacity to any accident because it works as the last barrier. The acceptable nuclear containment structure makes possible to limit the effect of internal accidents and to avoid radioactive release. In this study, to conduct the numerical analysis for the structural safety of a containment structure, loss of coolant accident (LOCA) is considered as the basic accidental load, and Wolsong containment structure is considered as a target structure. The CANDU containment structure, such as Wolsong containment structure, is a prestressed concrete shell structure which has dome and is reinforced with bonded tendons. The evaluation of ultimate pressure capacity was conducted by nonlinear analysis of a prestressed concrete containment structure.

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A Study on Natural Vibration Characteristics of Dome Structure According to Natural Frequency Ratio of Substructure (하부 구조의 고유 진동수비에 따른 돔 구조의 고유 진동 특성에 관한 연구)

  • Park, Kwang-Seob;Kim, Yun-Tae
    • Journal of Korean Association for Spatial Structures
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    • v.18 no.3
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    • pp.75-82
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    • 2018
  • Large space structures exhibit different natural vibration characteristics depending on the aspect ratio of structures such as half-open angle. In addition, since the actual large space structure is mostly supported by the lower structure, it is expected that the natural vibration characteristics of the upper structure and the entire structure will vary depending on the lower structure. Therefore, in this study, the natural vibration characteristics of the dome structure are analyzed according to the natural frequency ratio by controlling the stiffness of the substructure. As the natural frequency of the substructure increases, the natural frequency of the whole structure increases similarly to the natural frequency of the upper structure. Vertical vibration modes dominate at $30^{\circ}$ and $45^{\circ}$, and horizontal vibration modes dominate at $60^{\circ}$ and $90^{\circ}$.

How We Teach 'Structure' - Focusing on the Group Concept (어떻게 '구조'를 가르칠 것인가 - 군 개념을 중심으로)

  • 홍진곤
    • Journal of Educational Research in Mathematics
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    • v.10 no.1
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    • pp.73-84
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    • 2000
  • This study, after careful consideration on Piaget's structuralism, showed the relationship between Bourbaki's matrix structure of mathematics and Piaget's structure of mathematical thinking. This, studying the basic characters that structure of knowledge should have, pointed out that 'transformation' and to it, too. Also it revealed that group structure is a 'development' are essential typical one which has very important characters not only of mathematical structure but also general structure, and discussed the problem that learners construct the group structure as a mathematical concept.

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Structural Integrity Assessment of the Internal Structure (원전 기기 내부구조물에 대한 구조건전성평가)

  • Lee, Han-Hee;Choi, Jin-Young
    • Proceedings of the KSME Conference
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    • pp.3497-3500
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    • 2007
  • The internal structure is subjected to dynamic analysis due to the structural integrity. The internal structure shall be installed in the vertical hole call IR1 of reactor core. In order to verify the deflection of the internal structure, the mode and response spectrum analysis of the internal structure was performed. The natural frequency of the internal structure is 11.6 Hz(mode 1 and 2) and deflections of the internal structure are less than values of allowable design (3.2 mm).

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Mining Structure Elements from RNA Structure Data, and Visualizing Structure Elements

  • Lim, Dae-Ho;Han, Kyung-Sook
    • Proceedings of the Korean Society for Bioinformatics Conference
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    • pp.268-274
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    • 2003
  • Most currently known molecular structures were determined by X-ray crystallography or Nuclear Magnetic Resonance (NMR). These methods generate a large amount of structure data, even far small molecules, and consist mainly of three-dimensional atomic coordinates. These are useful for analyzing molecular structure, but structure elements at higher level are also needed for a complete understanding of structure, and especially for structure prediction. Computational approaches exist for identifying secondary structural elements in proteins from atomic coordinates. However, similar methods have not been developed for RNA due in part to the very small amount of structure data so far available, and extracting the structural elements of RNA requires substantial manual work. Since the number of three-dimensional RNA structures is increasing, a more systematic and automated method is needed. We have developed a set of algorithms for recognizing secondary and tertiary structural elements in RNA molecules and in the protein-RNA structures in protein data banks (PDB). The present work represents the first attempt at extracting RNA structure elements from atomic coordinates in structure databases. The regularities in the structure elements revealed by the algorithms should provide useful information for predicting the structure of RNA molecules bound to proteins.

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The Term and Classification of Structure System with Non-rigid Member (연성구조시스템의 분류체계와 용어)

  • Lee, Ju-Na;Park, Sun-Woo;Kim, Seung-Deog;Park, Chan-Soo
    • Journal of Korean Association for Spatial Structures
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    • v.4 no.2
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    • pp.99-105
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    • 2004
  • The structure systems with non-rigid member were classified by the composition type of line and surface members. As a result of the classification, there are 1-way cable structure, cable net and radial cable net structure in the line member system. And there are pneumatic structure and suspension membrane structure in surface member system. In addition, when the line and surface members are composed together, there is the hybrid membrane system which are divided into hanging type and supported type. In this paper, the Korean terms of structure systems with non-rigid member are recommended through this classification.

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Influence of structure-soil-structure interaction on foundation behavior for two adjacent structures: Geo-centrifuge experiment

  • Ngo, Van-Linh;Kim, Jae-Min;Lee, Changho
    • Geomechanics and Engineering
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    • v.19 no.5
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    • pp.407-420
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    • 2019
  • This paper illustrates the results of a series of seismic geotechnical centrifuge experiments to explore dynamic structure-soil-structure interaction (SSSI) of two structures (named S1 and S2) installed on ground surface. A dense homogeneous ground is prepared in an equivalent shear beam (ESB) container. Two structural models are designed to elicit soil-foundation-structure interaction (SFSI) with different masses, heights, and dynamic characteristics. Five experimental tests are carried out for: (1) two reference responses of the two structures and (2) the response of two structures closely located at three ranges of distance. It is found that differential settlements of both structures increase and the smaller structure (S2) inversely rotates out of the other (S1) when they interact with each other. S2 structure experiences less settlement and uplift when at a close distance to the S1 structure. Furthermore, the S1 structure, which is larger one, shows a larger rocking and a smaller sliding response due to the SSSI effects, while S2 structure tends to slide more than that in the reference test, which is illustrated by an increase in sliding response and rocking stiffness as well as a decrease in moment-to-shear ratio (M/H·L) of the S2 structure.

Study for Reformation on Building Structure Regulation (건축구조 관련규제의 개선방안 연구)

  • Chung, Pyung-Rahn
    • Journal of Korean Association for Spatial Structures
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    • v.10 no.1
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    • pp.111-117
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    • 2010
  • This thesis draws institutional problem about safety of architectural structure through analysis of architectural structure regulation. The law of analysis target are building codes, enforcement ordinance of building codes, enforcement regulations of building codes, regulation for structure standards of building, building structure standards. The analysis showed there are imperfections in confirmed procedural application of structure safety and suggested reformation. It's necessary to make supplementary policies for the suitability of the term use and the structure safety certificate of compliance, establishing a special structure code.

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NOTE ON CONTACT STRUCTURE AND SYMPLECTIC STRUCTURE

  • Cho, Mi-Sung;Cho, Yong-Seung
    • Bulletin of the Korean Mathematical Society
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    • v.37 no.1
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    • pp.181-189
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    • 2000
  • Let (X, J) be a closed, connected almost complex four-manifold. Let $X_1$ be the complement of an open disc in X and let ${\varepsilon}_1$be the contact structure on the boundary ${\varepsilon}X_1$ which is compatible with a symplectic structure on $X_1$, Then we show that (X, J) is symplectic if and only if the contact structure ${\varepsilon}_1$ on ${\varepsilon}X_1$ is isomorphic to the standard contact structure on the 3-sphere $S^3$ and ${\varepsilon}X_1$is J-concave. Also we show that there is a contact structure ${\varepsilon}_0\ on\ S^2\times\ S^1$which is not strongly symplectically fillable but symplectically fillable, and that $(S^2{\times}S^1,\;{\varepsilon})$ has infinitely many non-diffeomorphic minimal fillings whose restrictions on$\S^2\times\ S^1$are ${\sigma}$ where ${\sigma}$ is the restriction of the standard symplectic structure on $S^2{\times}D^2$.

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Evaluation of Effective Stiffness for 3D Beam with Repeated Structure

  • Chung, Il-Sup
    • International Journal of Precision Engineering and Manufacturing
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    • v.7 no.2
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    • pp.25-29
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    • 2006
  • Analysis of structures which are composed of numerous repeated unit structures can be simplified by using homogenized properties. If the unit structure is repeated in one direction, the whole structure may be regarded as a beam. Once the effective stiffness is obtained from the analysis of the unit structure in a proper way, the effort for the detail modeling of the global structure is not required, and the real structure can be replaced simply with a beam. This study proposes a kinematical periodicity constraint to be imposed on the FE model of the unit structure, which improves the accuracy of the effective stiffness. The method is employed to a one dimensionally arrayed 3D structure containing periodically repeated unsymmetrical holes. It is demonstrated that the deformation behavior of the homogenized beam agrees well with that of the real structure.