• Title/Summary/Keyword: structure

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SOME STRUCTURES ON A COMPLETE LATTICE

  • Lee, Seung On;Yon, Yong Ho
    • Journal of the Chungcheong Mathematical Society
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    • v.20 no.3
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    • pp.211-221
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    • 2007
  • In this paper, we define ${\bigwedge}$-structure, ${\bigvee}$-structure to generalize some lattices, and study the conditions that a lattice which has ${\bigwedge}$-structure or ${\bigvee}$-structure to be continuous or algebraic.

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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.

Evaluation of Effective Stiffness for 3D Beam with Repeated Structure (반복 구조로 구성된 3차원 보의 유효 강성 계산)

  • Chung Ilsup
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.7 s.172
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    • pp.170-176
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    • 2005
  • 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 un-symmetric holes. It is demonstrated that the deformation behavior of the homogenized beam agrees well with that of the real structure.

A Study on a Development of Hybrid(Magnesium & Steel) Structure for Application of Cockpit Module (Cockpit Module용 Hybrid Structure개발에 관한 연구)

  • 박병구;이정환;김영삼;한성수
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.6
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    • pp.166-170
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    • 2002
  • A hybrid structure composed of magnesium and steel is Instrument Panel structure used for the basement of cockpit module components. For that reason, A hybrid structure has to be designed for satisfying components assembly design facility and styling. There are various models of If like steel structure assembly, however having been applied normally, but magnesium structure assembly selected far saving weight down. This paper introduces a hybrid structure having advantages between steel and magnesium structure and presents a CAE technical solution based on a development project. furthermore, it provides desired direction of the future development is suggested.

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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A Study on The Structural Systems of Modern Architecture and Architectural Characteristics (근대건축의 구조시스템과 건축적 특성에 관한 연구)

  • Cho, Sung-Hyun
    • Journal of The Korean Digital Architecture Interior Association
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    • v.10 no.1
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    • pp.49-56
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    • 2010
  • The purpose of this study is to examine the relationship between the structural system used in modern architecture and the form and spatial composition of the buildings. The principle in stabilization of structures is closely related to the architectural form. That is, in order to stabilize a building, a special type of structural system is required and consequently shows up with consistent characteristics in the architectural form. Modern architecture can be classified into skeleton structure, trusses structure, and space structure according to the structural characteristics. Skeleton structure is then divided into a perpendicular form and tapered form. Trusses structure is categorized as dome-shaped structure and slab-shaped structure, and space structure can be divided into compressible space structure and tensile space structure. When classifies the modern building with the aspect of architectural effect, there is a possibility of trying to divide with effect of production, and its expression. Effect of production mean structural system and effect of expression mean space and plan.

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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An Analysis Study of Changes in Middle School Students' Mathematical Conceptual Structure Using a Learning Platform (수학 학습 플랫폼을 활용한 중학생의 문자와 식에 대한 개념 구조 변화 분석 연구)

  • Huh, Nan
    • East Asian mathematical journal
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    • v.39 no.2
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    • pp.167-181
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    • 2023
  • The purpose of this study is to confirm the possibility of whether learning using a math learning platform can be used to expand students' conceptual structure and to consider how to use it. To this end, first-year middle school students studied using a math learning platform. Then, the concept map created was compared and analyzed with the concept map created before learning to examine the change in the concept structure. The results of analyzing the concept map are as follows. First, the change in the hierarchical structure of the concept appeared as the division of the upper concept was subdivided. However, it has also been changed to comprehensively integrate and simplify higher concepts. The term-centered concept structure has changed to content-centered superordinate and subordinate concepts. In the concept structure, subordinate concepts linked to one higher concept were expanded and differentiated. Second, changes in the integrated structure did not form a linkage structure. The expansion of the integrated structure of concepts through learning using the learning platform was influenced by the composition of the learning contents designed in the learning platform.

A study on the optimal configuration of harbor structure under the combined loads

  • Cho, Kyu-Nam
    • Structural Engineering and Mechanics
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    • v.32 no.3
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    • pp.371-382
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    • 2009
  • Response of harbor structure to environmental loads such as wave load, impact load, ship's contacting load, is a fundamental factor in designing of the structure's optimal configuration. In this paper, typical environmental loads against coastal structures are investigated for designing of the optimal harbor structure. Loads to be considered here are wave load, impact load and contacting load due to ship mooring. Statistical analysis for several harbor structure types under the corresponding loads is carried out, followed by investigation of effect of individual environmental load. Based on these, the optimal configuration for the harbor structure is obtained after considerable engineering process. Estimation of contacting load of the ship is suggested using effective energy concepts for the load, and analysis of structural behavior is done for the optimal designing of the structure in the particular load. A guideline for the design process of the harbor structure is established, and safety of the structure is examined by proposed scheme. For verification of the analytical approach, various steel-piled coastal structures and caissons are chosen and relevant structural analyses are carried out using the Finite Element Methods combined with MIDAS/GTS and ANSYS code. It is found using the Morison equation that impact load cannot be a major load in the typical harbor structure compared with the original wave load, and that configuration shape of the structure may play an important role in consideration of the response criteria.