• 제목/요약/키워드: Structural restriction

검색결과 130건 처리시간 0.023초

매스콘크리트에서 최적의 타설 단면 결정을 위한 해석적 연구 (Analysis Study for the Determination of Optimized Block Size in Mass Concrete)

  • 김진근;김상철;이두재;김국한
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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    • pp.422-429
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    • 1997
  • Thermal stress induced by hydration heat may produce cracks in mass concrete structure, which can result in structural problems as well as bad appearance. To minimize crack occurrence in massive structural, thus, the study put an emphasis on the determination of optimized lift height and block size. In the parametric study different sizes and lift heights were used to measure the magnitudes of hydration heat and thermal stresses for 3 different types of concrete fabricated with 1 pure cement and 2 blended Portland cements. As a result of analysis. it was found that magnitude of hydration heat and the occurrence of thermal cracks depend on the restriction conditions and material characteristics, especially adiabatic material parameters. It was also found that optimized lift height and block size can be determined from an appropriate combination of the degree of inner and outer structural restrictions.

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다문화가정 이주여성의 여가관 분석 (Analysis on Leisure ViewPoint of Immigrant Female of Multi-Cultural Families)

  • 윤민숙;이정흔;김정련
    • 한국콘텐츠학회논문지
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    • 제11권6호
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    • pp.337-349
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    • 2011
  • 연구의 목적은 다문화가정 이주여성의 여가관 분석을 규명하는데 있다. 이 연구는 2010년 경기도 대전 충남 충북 지역 소재 다문화가정지원센터 프로그램에 참가하고 있는 이주여성들을 모집단으로 선정한 다음 유의표집방법(purposive sampling method)을 활용하여 140명의 연구대상을 표집 하였다. 최종분석에 사용된 사례수는 총 89명이다. 설문지의 신뢰도는 Cronbach's ${\alpha}$ 값이 .613이상으로 나타났다. 결론은 다음과 같다. 첫째, 다문화가정 이주여성들의 평일 여가시간은 '1~2시간'이 가장 많다. 둘째, 다문화가정 이주여성들의 주말 여가시간은 '1~2시간'이 가장 많다. 셋째, 다문화가정 이주여성들의 여가활동만족은 '보통'이 가장 많다. 넷째, 다문화가정 여가활동 선호도는 '여행'이 가장 많다. 다섯째, 다문화가정 이주여성들의 여가활동 동반자로는 '배우자'가 가장 많다. 여섯째, 연령, 학력, 국적, 기간에 따라 다문화가정 이주여성들의 여가제약은 차이가 있다.

디젤기관용 Urea-SCR 시스템 펌프 기어에 관한 구조해석 (Structural Analysis of Pump Gear of Urea-SCR System for Diesel Engine)

  • 이홍윤;박충열;김형민;김세진;최두석
    • 한국자동차공학회논문집
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    • 제24권1호
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    • pp.10-15
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    • 2016
  • This research was conducted structural analysis in order to analyze the impact of the gear in Urea pump when the water is frozen. Subject of study, gear was designed nine models, this gear is a spur gear, located in pump. Contact conditions and rotation conditions were set the gear's condition of restriction. Given 136 MPa pressure to external gear by water was set to the applied stress. The performing result of structural analysis, maximum stress and strain are appeared between two gears. At the same diameter, strain and stress are decreased gradually thicker. Because of the little part in crevice between gears, this parts of gears could be obtained conclusion to be generated maximum stress and strain.

Effects of modelling on the earthquake response of asymmetrical multistory buildings

  • Thambiratnam, David P.
    • Structural Engineering and Mechanics
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    • 제2권2호
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    • pp.211-225
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    • 1994
  • Responses of asymmetrical multistorey buildings to earthquakes are obtained by quasi-static code approach and real time dynamic analysis, using two different structural models. In the first model, all vertical members are assumed to be restrained at the slab levels and hence their end rotations, about horizontal axes, are taken as zero. In the second model this restriction is removed and the rotation is assumed to be proportional to the lateral stiffness of the member. A simple microcomputer based procedure is used in the analyses, by both models. Numerical examples are presented where results obtained from both the models are given. Effects of modelling on the response of three buildings, each with a different type and degree of asymmetry, are studied. Results for deflections and shear forces are presented and the effects of the type of model on the response are discussed.

박막을 이용한 저주파수 영역 덕트 소음 저감 방법 (Low Frequency Noise Reduction Inside Duct by Using Membrane)

  • 김양한
    • 한국소음진동공학회논문집
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    • 제14권11호
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    • pp.1083-1090
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    • 2004
  • Two noise reduction systems are proposed in order to overcome the geometric restriction of the reactive muffler such as an expansion chamber. First, membrane is installed as a part of a duct wall and an air cavity is covered outside membrane. Second, membrane is installed inside a duct, which gives no volume change of the duct. Structural-acoustic coupling between membrane and fluid inside the cavity and duct causes rapid impedance mismatching and thereby reflected wave. Theoretical prediction is conducted by using modal expansion approach. The results are compared with the experimental results, which show better noise reduction performance than an expansion chamber.

박막을 이용한 저주파수 영역 덕트 소음 저감 방법 (Low frequency noise reduction inside duct by using membrane)

  • 전종훈;김양한
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 춘계학술대회논문집
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    • pp.474-479
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    • 2004
  • Two noise reduction systems are proposed in order to overcome the geometric restriction of the reactive muffler such as an expansion chamber. First, membrane is installed as a part of a duct wall and an air cavity is covered outside membrane. Second, membrane is installed inside a duct, which gives no volume change of the duct. Structural-acoustic coupling between membrane and fluid inside the cavity and duct causes rapid impedance mismatching and thereby reflected wave. Theoretical prediction is conducted by using modal expansion approach. The results are compared with the experimental results, which show better noise reduction performance than an expansion chamber.

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부유식 해양도시의 동적응답특성 (Dynamic Response Characteristics of a Floating Ocean City in Waves)

  • 구자삼;홍석원
    • 한국해양공학회지
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    • 제8권2호
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    • pp.80-92
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    • 1994
  • The dynamic response characteristics of a floating ocean city are examined for presenting the basic data for the design of huge offshore structures supported by a large number of floating bodies in waves. The numerical approach which is accurate in linear system is based on combination of a three dimensional source distribution method, wave interaction theory and the finite element method of using the space frame element. The hydrodynamic interactions among the floating bodies are taken into account in their exact form within the context of linear potential theory in the motion and structural analysis. The method is applicable to an arbitrary number of three dimensional bodies having any individual body geometries and geometrical arrangement with the restriction that the circumscribed, bottom-mounted. Imaginary vertical cylinder for each body does not contain any part of the other body. The validity of this procedure was verified by comparing with experimental results obtained in the literature.

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연성해석과 통계적 방법을 이용한 Butterfly Valve의 다목적 최적설계 (Multi-objective Optimization of Butterfly Valve using the Coupled-Field Analysis and the Statistical Method)

  • 배인환;이동화;박영철
    • 한국정밀공학회지
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    • 제21권9호
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    • pp.127-134
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    • 2004
  • It is difficult to have the existing structural optimization using coupled field analysis from CFD to structure analysis when the structure is influenced of fluid. Therefore in an initial model of this study after doing parameter design from the background of shape using topology optimization. and it is making a approximation formula using by the CFD-structure coupled-field analysis and design of experiment. By using this result, we conducted multi-objective optimization. We could confirm efficiency of stochastic method applicable in the scene of structure reliability design to be needed multi-objective optimization. And we presented a way of design that could overcome the time and space restriction in structural design such as the butterfly valve with the less experiment.

기립상태에서 비정상적 무릎관절 굴곡에 대한 보존적 치료 임상사례연구 (Clinical Case study of Conservative Caring Method to Abnormal Knee Flexion in Standing Position)

  • 조일영
    • 한국콘텐츠학회논문지
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    • 제9권1호
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    • pp.323-330
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    • 2009
  • 무릎의 신전이 방해되는 이유는 여러 가지가 있다. 하지만 우리가 특별히 구조적인 기형을 환자에게서 찾아내지 못하는 한 넙다리근육 강화나 신전을 위한 하지 폄근육군 완화운동 방법을 알려주는 것 이외에 별달리 해줄 수 있는 것이 없다. 이 연구에서 저자는 Sacro-Occipital Technique을 활용한 무릎 움직임 방해 완화에 대하여 새로운 사례연구를 하였다. 이 연구에서는 무릎을 완전히 펴고 서지 못하는 14세의 여학생에게 7회의 S.O.T categoryⅠ. 방법이 적용되었으며 이로서 별다른 방해 없이 무릎을 펴고 설수 있게 되었다. 대체적으로 무릎을 곧바로 펴지 못하는 많은 경우 근육 연조직 마사지 등을 뒤넙다리근에 적용하여 완화 시켜 보기도 한다. 그러나 만약 이러한 방법들이 잘 듣지 않는다면 S.O.T categoryⅠ. 방법을 고려하여 보는 것도 도움이 될 수 있을 것으로 사료된다.

'양식산업발전법' 제정의 의의와 문제점 분석 (An Analysis on Significance and Problems of Aquaculture Industry Development Act)

  • 신용민
    • 수산경영론집
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    • 제51권1호
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    • pp.1-17
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    • 2020
  • This study is an analysis of the Aquaculture Industry Development Act that has recently been passed by the National Assembly. In order to improve the structural problem of Korea's aquaculture, a large revision of aquaculture related laws and regulations is needed. The enactment of Aquaculture Industry Development Act is necessary to that effect. It is adequate to aim for development as aquaculture industry not as aquaculture, to alleviate entry restriction of aquaculture, and to provision diverse promotion and support policies. However, it is a concern whether the current Aquaculture Industry Development Act can achieve its goal of enhancing the competitiveness of aquaculture and sustainability. Rather than to solve the problem, the act holds the possibility of further fixing or exacerbating the problem. So there is concern for side-effects after the enactment. This is due to the fact that it complicates terminologies by unnecessarily differentiating aquaculture related concepts from the existing Fisheries Act, lacks regulations regarding voluntary participation in aquaculture, and has limited methods to alleviate entry restriction. In addition, there are very few measures for the scale improvement of aquaculture along with the unlikeliness of a significant effect of the review and evaluation for re-licensing. Thus, the Aquaculture Industry Development Act should promptly be revised after its enactment.