• Title/Summary/Keyword: structure

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The Performance of Insulation of Noise by Air between Floors According to Structure Systems of Apartment (공동주택 구조형태별 층간 공기전달음 차단 성능)

  • Lee, Byung-Kwon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.1152-1155
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    • 2007
  • Lately concerns about structure have been increased by advantages of floor impact noise, poilitical induction and changeability. Hence, Flat Plate Structure has been constructed increasingly. This study shows the comparison of the performance of sound insulation of Flat Plate Structure System and the existing Wall Structure. For this study, taking the same level organization of Daelim Architectural Environmental Research Center, I found the performance of sound insulation between the upper and lower floors about Wall Structure and Flat Plate Structure. Consequently, the performance of sound insulation between upper and lower floors of Flat Plate Structure was 3-5dB higher was approximately 3-5dB higher than one of Wall Structure. Especially, the performance of sound insulation on the upper floor was 1-3dB higher than on the lower floor. In addition, as the result of comparing radiation sound which radiates from the wall of lower floors with each structure system, Flat Plate Structure was about 4dB higher with Rw than Wall Structure. As we see totally, the performance of sound insulation of Flat Plate Structure is highter than one of the Wall Structure. It is 3-5dB higher and the main reason for this result depends on the existence of the wall which can radiate sound and nonexistence.

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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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    • 2005.04a
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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 $90^{\circ}$.

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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    • 2007.05b
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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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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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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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    • 2003.10a
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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 s.12
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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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The Development and Historical Character for Structure System with Non-rigid Member (연성구조시스템의 발달과정과 역사적 특성)

  • Lee, Ju-Na;Park, Sun-Woo;Park, Chan-Soo
    • Journal of Korean Association for Spatial Structures
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    • v.4 no.3 s.13
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    • pp.93-101
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    • 2004
  • Structural systems have a lot of architectural meaning concerning historical context of structural technology. Therefore, surveying constructed examples and their constructed year, the character and development of various formations of structure systems with non-rigid member were investigated. At the result, the early modem structure systems with non-rigid member were made up from the cable structures, then membrane structures have mainly used after 1970's. The early structural systems had intended to make the large scale space, after 1970's, they have been adopted into the smaller scale space structure, and cable net structure, pneumatic structure and dome typed hybrid membrane system tend to compose the larger scale spare structure.

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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.

Seismic retrofit of a soft first story structure considering soil effect

  • Michael Adane;Jinkoo Kim
    • Earthquakes and Structures
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    • v.24 no.5
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    • pp.345-352
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    • 2023
  • This paper studied the effect of soil-structure interaction (SSI) on the seismic response and retrofit of a reinforced concrete structure with a soft-first story for different soil types. A 5-story structure built on a 30m deep homogeneous soil mass was considered as a case study structure, and steel column jacketing and steel bracing were chosen as seismic retrofit methods. Seismic responses of a fixed-base and a flexible base structure subjected to seven scaled earthquake records were obtained using the software OpenSees to investigate the effect of soil on seismic response and retrofit. The nonlinearBeamColumn elements with the fiber sections were used to simulate the nonlinear behavior of the beams and columns. Soil properties were defined based on shear wave velocity according to categorized site classes defined in ASCE-7. The finite element model of the soil was made using isoparametric four-noded quadrilateral elements and the nonlinear dynamic responses of the combined system of soil and structure were calculated in the OpenSees. The analysis results indicate that the soil-structure interaction plays an important role in the seismic performance and retrofit of a structure with a soft-first story. It was observed that column steel jacketing was effective in the retrofit of the model structure on a fixed base, whereas stronger retrofit measures such as steel bracing were needed when soil-structure interaction was considered.