• Title/Summary/Keyword: 돔 형태

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피동형 격납건물 냉각계통 내 돔 효과의 수치적 해석에 관한 연구

  • 전지한;박홍준;이은철
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.05a
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    • pp.298-303
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    • 1997
  • 실제의 격납건물의 구조는 하부 원통형의 구조를 가지는 영역과 상부 돔 형태와 굴뚝 형태의 구조를 가지는 영역으로 나눌 수 있다. 하부 원통형의 구조만을 고려한다면, 고온의 철제 벽면과 콘크리트 벽면 사이의 gap 크기에 비해서 원통의 반지름이 상대적으로 매우 큰 값을 가지기 때문에 2차원 무한평판으로 가정하는 것이 가능하다. 그러나 돔 및 굴뚝 영역에서는 높이가 높아질수록 돔 단면직경이 감소하고 굴뚝 영역도 유동단면적이 작은 원통의 구조를 가져 2차원 무한평판의 가정에 많은 무리가 따른다. 앞에서 명시한 세 가지의 격납건물 형태에 있어서 ASPWR의 경우는 굴뚝을 포함한 영역까지도 무한평판으로 가정하는 것이 가능하나(돔에서의 열전달 단면적이 하부의 열전달 단면적에 비해 매우 작다는 가정을 한다면) 나머지 AP600과 HWRF의 격납건물에 있어서는 상부까지도 무한평판 가정을 사용하는 것에는 무리가 있다. 본 연구에서는 일반적인 유체해석 코드인 FLUENT V4.3을 이용하여 실제 격납건물 구조에 대한 분석을 시도하여 무한평판 구조에 대한 가정이 과도한 열전달량을 예측하고 있음을 확인하였다.

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Optical design of secondary lens considering a shape of LED dome (LED 돔 형태를 고려한 2차렌즈의 설계)

  • Lee, Min-Wook;Oh, Hye-Young;Kim, Hoon
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.05a
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    • pp.190-192
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    • 2009
  • LED를 광원으로 사용하는 조명기구는 용도에 맞는 적합한 배광을 가져야 한다. LED 조명기구의 배광을 달성하는 LED 2차 렌즈의 설계를 위해서는 LED의 기본 배광이 고려되어야 하며 일반적으로 기본 배광은 LED 돔의 형태에 따라 달라진다. 일반적으로 사용되는 램버시안 배광을 갖는 LED를 기본으로 하여 돔 형태 및 기본배광이 다른 각각의 LED에 대한 2차 렌즈를 설계하고 시뮬레이션을 통해 그 성능을 평가하였다.

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Morphological Study of the Genus Chromis from Korea - I. External Morphology of Three Damselfishes of the Genus Chromis(Teleostei: Pomacentridae) from the Korean Waters (한국산 자리돔속 어류의 형태학적 연구 - I. 한국산 자리돔속 어류 3종, 자리돔 Chromis notata, 노랑자리돔 C. analis, 연무자리돔 C. fumea의 외부형태학적 연구)

  • Kim, Yong-Uk;Kim, Jin-Koo
    • Korean Journal of Ichthyology
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    • v.8 no.2
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    • pp.23-32
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    • 1996
  • External morphology of three species of damselfishes, Chromis notata, C. analis and C. fumea were studied based on the samples collected from the Korean waters from 1993 to 1994. In morphology of the black spot at base of pectoral fins, C. notata has a large triangluar spot at Cheju population and a small circular spot at Sin - am. In the length of pelvic fin, C. notata of Korea can be classified into 3 groups. First group has a pelvic fin that extends to the origin of anal fin, second extends to the anus, third not extend to the anus. C. analis has higher body depth than C. notata and C. fumea in % of standard length. C. fumea has a minute serrate preopercle and no black spot at base of pectoral fins. In distribution, C. notata has a more widly distriubtion area than C. analis and C. fumea. Therefore, C. notata has more tolerance of cold waters than C. analis and C. fumea.

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An Experimental Study on the Buckling & Behaviour of Single-Layer Latticed Dome (단층 래티스 돔의 좌굴 및 거동에 관한 실험적 연구)

  • Kim, Cheol-Hwan;Jung, Hwan-Mok
    • Journal of Korean Association for Spatial Structures
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    • v.6 no.4 s.22
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    • pp.35-44
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    • 2006
  • The form-resistant Systems like a dome and shell are used more widely than post-beam structure system in large space structure. Single layer latticed dome system, one of the form-resistant system, has great merits in manufacturing and constructing but the failure mechanism is not clarified yet. The purpose of this paper is to find out the buckling characteristics of single-layer latticed domes with square network by using the experimental method. Major test parameters are the stiffness of lattice member and space of square lattice. The specimens are applied uniform loading of snow type.

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Morphological Study on the Fishes of the Family Pomacentridae I. A Taxonomical Revision of the Family Pomacentridae (Pisces; Perciformes) from Korea (자리돔과 (Family Pomacentridae) 어류의 형태학적 연구 1. 자리돔과 어류의 분류학 적 재검토)

  • 고정락;명정구;김용억
    • Animal Systematics, Evolution and Diversity
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    • v.13 no.2
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    • pp.173-192
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    • 1997
  • Three damselfishes, Dascyllus melanurus, Dascyllus trimaculatus and Poamcentrus nagasakiensis were collected in the coastal waters of Cheju Island, Korea, during the period from July 1994 to May 1997. These taxa were a new records to th Korean fish fauna. This study re-describe about family Pomacentridae (6 genera, 13 species) including 3 new recorded species and suggest the taxonomic key of family pomacentridae from Korea.

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A Report on Gneiss Dome in the Hongseong Area, Southwestern Margin of the Gyeonggi Massif (경기육괴 남서 연변부 홍성지역에 발달하는 편마암 돔에 대한 보고)

  • Park, Seung-Ik;Kim, Sung Won
    • Economic and Environmental Geology
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    • v.49 no.4
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    • pp.315-323
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    • 2016
  • This study reports a gneiss dome in the Hongseong area, southwestern margin of the Gyeonggi massif. This gneiss dome, named here as 'Oseosan dome' because it is located around the Oseosan, the highest peak along the western coastal area, is composed mainly of the Neoproterozoic to Paleozoic ortho- and paragneiss, mafic metavolcanic rock, and metadolerite. Migmatization affected these rock units, in which leucocratic(granitic) materials derived from anatexis frequently occur as patch and vein parallel to or cutting through internal foliation. The Oseosan dome shows overall concentric geometry and outward-dipping internal foliation, but also partly complicatedly changeable or inward-dipping foliation. Taking available petrological and geochronological data into account, the Oseosan dome is interpreted to be exhumed quickly into the upper crustal level during the Late Triassic, accompanied in part with anatexis and granite intrusion. In addition, extensional shear zone intruded by the Late Triassic synkinematic granite and sedimentary basin have been reported around the Oseosan dome. These evidences possibly suggest that the Oseosan dome formed in closely associated with the Late Triassic extensional movement and diapiric flow. Alternatively, 1) thrust- or reverse fault-related doming or 2) interference between independent folds during structural inversion of the Late Traissic to Middle Jurassic sedimentary basin can be also considered as dome-forming process. However, considering the northern limb of the Oseosan dome, cutting by the Late Traissic granite, and the southern limb, cutting by contractional fault reactivated after the Middle Jurassic, it is likely that the domal structure formed during or prior to the Late Triassic.

THE FORMAL ANALYSIS OF PANTHEON IN ROME IN RELATION TO THE SOLAR ANGLES (로마 판테온의 일조특성 연구)

  • Lim, Choong-Shin
    • Journal of architectural history
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    • v.7 no.4 s.17
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    • pp.191-198
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    • 1998
  • The form of Pantheon in Rome is graphically analyzed in relation to the angle of the Sun that varies through four seasons of the year. These are worked out in the Autocad drawing files for exactitude and efficiency. Some of the results suggest that the Pantheon is carefully designed to predict the equinoxes and the solstices.

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Performance Evaluation of Welded Joints for Single-Layer Latticed Domes through Joint Rigidity Test (단층 래티스 돔에 적용 가능한 용접 접합부의 휨실험을 통한 성능 평가)

  • Lee, Young Hak;Seo, Sang Hoon;Kim, Min Sook;Kim, Hee Cheul;Lee, Sung Min
    • Journal of Korean Society of Steel Construction
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    • v.20 no.5
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    • pp.601-608
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    • 2008
  • Joints of single-layer latticed domes show various flexural behaviors according to their shapes and connecting methods. Ball joints are relatively easy to apply and build while their rigidities are relatively small and have disadvantage in long span. Welded joints have many advantages in rigidity, internal force and long span. However few experimental studies have been performed. In this paper, improved welded joint for the single layer latticed domes was proposed through both analytical and experimental analyses. Length of inserted plates, thickness of inserted plates and hole of sub steel pipes were selected as parameters for experimental comparisons and defining the effects of the selected variables.

A Study on the Characteristics of Nonlinear Unstable Phenomenon According to the Shape Variation of Cable Domes (케이블 돔 구조물의 형태 변화에 따른 비선형 불안정 거동의 특성에 관한 연구)

  • Kim, Seung Deog;Back, In Seong;Kim, Hyung Seok
    • Journal of Korean Society of Steel Construction
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    • v.16 no.3 s.70
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    • pp.345-353
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    • 2004
  • One of the key issues in spatial structures with large spaces is how to carry the weight of the roof. This can be solved by the effective use of tension members. A cable dome structural system facilitates the construction of a large space structure. As external load increases, however, the cable dome structural system is put at risk due to global buckling. This study measures the shape of the Geiger and Flower-type cable dome by applying an initial stress. This unstable phenomenon is also examined using a perfectly shaped model and an imperfect model, which are both subjected to an axisymmetric load.

Petrology of the Sanbangsan Lava Dome, Jeju Volcanic Field (제주도 산방산 용암돔(Lava Dome)의 구성암석에 대한 화산암석학적 연구)

  • Yun, Sung-Hyo
    • The Journal of the Petrological Society of Korea
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    • v.28 no.4
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    • pp.307-317
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    • 2019
  • Petrological studies were performed on the Sanbangsan lava dome, located in the southwest of Jeju Island Volcanic Field. According to the lava ejection method, it is 'an internal primitive form' that is gradually pushed up and expanded by continuous magma injection from the bottom to the top of the vent and it corresponds to the 'low lava dome'. The rocks are partly plotted in the field of benmoreite, but mostly plotted in the field of trachyte of the Cox et al.(1979) classification diagram, and also mainly plotted in the field of trachyte of Le Maitre et al.(2002) and Zr/TiO2-Nb/Y classification diagram. Therefore, the expression that described the rock of Sanbangsan lava dome as 'trachy-andesite' should be corrected to 'trachyte'. The volcanic rocks that consists in the Sanbangsan lava dome are trachyte containing normative quartz and shows differentiation trend in the range of 59.75-63.46 wt.% SiO2.