• 제목/요약/키워드: COMPOSITION AND STRUCTURE

검색결과 3,085건 처리시간 0.042초

레이저 용접조건에 따른 증발된 합금원소의 조성과 구조의 변화 (Chemical Compositio and Structure of Evaporated Alloying Element by Laser Welding Condition)

  • 조상명
    • Journal of Advanced Marine Engineering and Technology
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    • 제23권4호
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    • pp.523-532
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    • 1999
  • This study is aimed to obtain fundamental knowledge of pulse laser welding phenomena the authors investigated the structure and composition of evaporated particles of Al alloys in air and in the Ar atmosphere during pulsed laser welding. The ultra-fine particles of 5 to 100nm diameter in a globular or irregular shape were formed in laser-induced plasma and the main structure was $MgAl_2O_4$ The composition of particles was ifferent depending on the power density of a laser beam; namely under the low power density conditions magnesium was predominant in the parti-cles while aluminium content increased with an increase in the power density. These results were attributed to evaporation phenomena of metals with different boiling points and latent heats of vaporization. On the other hand the number density of laser-induced plasma species was obtained by Saha's equation. it was confirmed that the number density depends upon the plasma tempera-ture and total pressures.

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Correlation between composition and structure of PtxNiy alloy nanodendrites

  • Lee, Young-Woo;Kwak, Da-Hee;Park, Kyung-Won
    • 한국결정성장학회지
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    • 제26권5호
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    • pp.165-170
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    • 2016
  • We have synthesized $Pt_xNi_y$ alloy nanodendrites by a thermal decomposition method. The structure and composition of the as-prepared samples were characterized by field-emission transmission electron microscopy (FE-TEM), energy dispersive X-ray (EDX) spectroscopy, and X-ray diffraction (XRD). The growth mode of the $Pt_xNi_y$ alloy samples synthesized as a function of an intended atomic fraction of Ni was likely to be strongly affected by and reduction (or oxidation) potentials and surface energy.

열린 내러티브 구조를 이용한 환경설계 방법 연구 - 용산 아리랑 문화공원을 설계사례로 - (A Study on Environmental Design Method based on Open Narrative Structure - A Case of Designing of Arirang Culture Park -)

  • 이상경;조경진
    • 한국조경학회지
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    • 제31권2호
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    • pp.12-27
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    • 2003
  • The purpose of this study is to look for an environmental design method based on open narrative structure, and to promote various experiences and interpretations of space through user's engagements. That is to say, the designer does not lead specific events through separate Boning but using the continuous open composition users are provided with margins for their imaginations. Spatial formulation through open narrative structure gives us various thoughts and it plays an important role in making a sequential space. Like an abstract painting, it is a complex story making or arranging a montage of images containing stories that elicit the reader's engagement through diverse interpretations. Like this, open composition exists in an ambiguous state and it is possible to interpret unfinished‘evolving work’within it. Utilizing open narrative structure, this study attempts to apply the idea of sequencing and open composition in the case of designing Arirang Culture Park. Open composition should induce various engagements by users and could be a medium which organically connects nature, culture and people. The spatial strategies of‘ambiguity’ and‘transparency’are like a bundle of complex and heterogeneous factors. Finally, the study focuses on the ‘integration’of the main ideas that compose multilayered space. ‘Voidness’and‘thickening’are also used for spatial strategies in open narrative structure. As alternative plans for undecided programs of the space, the voidness can be a strategic design program with flexibility about changes of futures. Also, thickening can be a strategic design program for functional reinforcement of the space, for the dramatic effects and for the generation of incidental events. Although both voidness and thickening seem paradoxical, we can see they are similar in the way that both focus on various spatial uses and by how they do not function as one-to-one correspondence, but as multiple correspondences. Therefore, open narrative structure is possible to apply in designing space and it can be an alternative design strategy for inducing multiple interpretations of space.

Intermediate Data Structure for MPEG-4 Scene Description

  • Cha, Kyung-Ae;Kim, Hee-Sun;Kim, Sang-Wook
    • 한국멀티미디어학회:학술대회논문집
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    • 한국멀티미디어학회 2001년도 춘계학술발표논문집
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    • pp.192-195
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    • 2001
  • MPEG-4 content is streaming media that are composed of different types of media objects, organized in a hierarchical fashion. This paper proposes scene composition model for authoring MPEG-4 contents which can support object based interactions. And we have developed MPEG-4 contents authoring tool applied the proposed scene composition model as intermediate data structure. Particularly, for supporting interoperability between multimedia contents, the scene composition model should be used independent of file format. So visual scene composed of media objects on the from of scene composition tree can be transformed variable data format including BIFS, scene description from proposed by MPEG-4 standard and also support the extension of capability.

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Composition and Structure of Macrofouling Communities on Ocean-going Ships in the Far East Sea Basin

  • Moshchenko, Alexander V.;Zvyagintsev, Alexander Y.
    • Ocean and Polar Research
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    • 제23권2호
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    • pp.63-75
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    • 2001
  • Species composition and community structure of the fouling found on the hulls of 28 ships traveling through 6 main shipping routes (SR)in the Far East Sea Basin were analyzed using statistical methods. Samples obtained during 1976-1990 expeditions of the Institute of Marine Biology were used for the analyses. These samples were taken from the ships anchored in the harbor by SCUBA diving and in dry-docks of the Vladivostok ship-repairing yard. Similar composition of the fouling communities occurred on the ships travelling the same SR. In five cases, fouling was dominated by different Cirripedia communities. And, in one case, a community of the mussel Mytilus trossulus was found. In most cases the results of the factor analyses showed extremely low level of the relationships among different animals and algal species in fouling communities. Each ocean-going ship had an original structure of the fouling. Spatially disconnected animal associations of tropical and boreal origin may simultaneously coexist at the same ship. This paper testified to the originality of the zone of anthropogenic substrata as a benthos concentrator in the pelagic regions of the world ocean. The fouling from different zones showed that each zone possesses peculiar features and regularities of the composition and relationships between organisms dwelling here.

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Study on the Mechanical Properties of TiAl Crystals Grown by a Floating Zone Method

  • Han, Chang-Suk;Kim, Sang-Wook
    • 한국재료학회지
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    • 제27권7호
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    • pp.369-373
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    • 2017
  • Unidirectionally solidified TiAl alloys were prepared by optically-heated floating zone method at growth rates of 10 to 70 mm/h in flowing argon. The microstructures and tensile properties of these crystal bars were found to depend strongly on the growth rate and alloy composition. TiAl alloys with composition of 47 and 50 at.%Al grown under the condition of 10 mm/h showed $Ti_3Al({\alpha}_2)/TiAl({\gamma})$ layer structures similar to single crystals. As the growth rate increased, the alloys with 47 and 50 at.%Al compositions showed columnar-grain structures. However, the alloys fabricated under the condition of 10 mm/h had a layered structure, but the alloy with increased growth rate consisted of ${\gamma}$ single phase grains. The alloy with a 53 at.%Al composition showed a ${\gamma}$ single phase regardless of the growth rate. Room-temperature tensile tests of these alloys revealed that the columnar-grained material consisting of the layered structure showed a tensile ductility of larger than 4 % and relatively high strength. The high strength is caused by stress concentration at the grain boundaries; this enhances the secondary slip or deformation twinning across the layered structure in the vicinity of the grain boundaries, resulting in the appreciable ductility.

합성가스(H2/CO) 예혼합 충돌 제트화염에서 조성비에 따른 부상 화염구조에 관한 연구 (A Study on the Lift Flame Structure with Composition Ratios in Premixed Impinging Jet Flames of Syngas (H2/CO))

  • 김슬기;심근선;이기만
    • 한국수소및신에너지학회논문집
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    • 제27권2호
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    • pp.220-229
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    • 2016
  • A numerical study on lifted flame structure in impinging jet geometry with syngas composition ratio was investigated. The numerical calculations including chemical kinetic analysis were conducted using SPIN application of the CHEMKIN Package with Davis-Mechanism. The flame temperature and velocity profiles were calculated at the steady state for one-dimensional stagnation flow geometry. Syngas mixture compositions were adjusted such as $H_2:CO=10:90(10P)$, 20 : 80 (20P), 30 : 70 (30P), 40 : 60 (40P), 50 : 50 (50P). As composition ratios are changed from 10P to 50P, the axial velocity and flame temperature increase because the contents of hydrogen that have faster burning velocity increase. This phenomenon is due to increase in good reactive radicals such as H, OH radical. As a result of active reactivity, the burning velocity is more faster and this is confirmed by numerical methods. Consequently, combustion reaction zone was moved to burner nozzle.

시뮬라크르 관점에서의 한국적 패션디자인 분석 (Analysis of Korean Fashion Design Seunghee Suh from the Viewpoint of Simulacre)

  • 서승희;김한나
    • 패션비즈니스
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    • 제23권5호
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    • pp.19-30
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    • 2019
  • The aim of this study is to analyze the stage of image change in Korean fashion design in regards to the simulacre of Jean Baudrillard. The changing phases of Korean fashion design are as follows: First, the initial stage involved simple imitation, which replicated the original as much as possible, it expressed the basic composition of Hanbok, flat cut and rich silhouette, the color scheme of traditional colors, traditional patterns, materials, and traditional ornaments. In the second stage, the subject matter intervened to distort and transform from the original, the basic composition and structure of the Hanbok were barely maintained, they were either removed or part of the structure modified or expressed using modern materials and patterns. The third stage, were based on reality but differed from reality through subject and imagination, and only left a part of the basic composition of Hanbok, and were expressed through the partial modification of the elements of the Hanbok, for instance the silhouette, skirt waist, collar and breast-tie. The fourth stage of pure simulacre, which refers to a new image with complete independence regardless of the reality. This stage differed from the basic structure and composition of Hanbok, and showcased traditional Korean image of Korea's unique cultural elements, such as hanbok or crafts and artworks, in a modern fashion with a modern sense and practicality.

학교체육관의 구조계획을 위한 구조시스템 구성요소의 변화와 건축특성의 영향분석 (An Analysis on the Relationship of Architectural Features and Composition Elements for Structure Planning in School Gymnasium)

  • 이주나
    • 교육시설 논문지
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    • 제26권5호
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    • pp.25-36
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    • 2019
  • School gymnasium is a multi-purpose large space building for various events and physical education activities, and is a facility that requires an approach to the desirable structural design, besides mechanical problems of structure against loads. For the integrated structure design concerning the architectural features, the major considerations of gymnasium planning that are the internal and external shape of the gymnasium, the space scale with structure members, the structural efficiency by members weight reduction and openness of the gymnasium space will have to take into account in the structural planning. From this point of view, the several cases of the school gymnasium were investigated and the parametric analyses were performed to the models using the various structural system. The parameters were the composition elements of structure system that are profile of structure, rigidity of member, connection and anchorage and stability. At the result, It was presented that the profile of structure member was the most influential factor to structural efficiency and the effect of the form and space of gymnasium. Also the design informations of structure design having the various feature of form and space were presented for the initial gymnasium planning.

통시적 분석에 의한 통도사의 공간구성 수법에 관한 연구 (A Study on Way of Spatial Composition of Tongdo Temple by Diachronic Analysis)

  • 강영조
    • 한국조경학회지
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    • 제27권3호
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    • pp.50-57
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    • 1999
  • This study aim to clarify the way of spatial composition of Tongdo Temple by diachronic analysis. The way of spatial composition was clarified through the analysis of built in architectural system in three periods. The result are as follows; 1. Spatial composition of Tongdo temple was changed in three period that it were establishment period, 1300s, and 1700s by the transition of meaning structure occurring the transition of spatial composition. 2. It was found out that the wat of spatial composition was three through the diachronic analysis the transition of spatial composition in Tongdo temple. 3. Juxtaposition as a way of spatial composition found out through the diachronic analysis is equivalent articulation of three sections; an upper, a middle, and a lower section and polyaxis or polycore in the each sections. Fusion is heterogenetic minglement mingling different kind of buildings and conjugation conjugating different kind of decorations. And accumulation of layer is mutilayer laying different time of layer and multi aspect aligning different kind of aspects since the temple's establishment.

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