• Title/Summary/Keyword: 특이형상

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Boundary Element Analysis of a Crack Normal at the Bondline of Two Dissimilar Materials (서로 다른 두 재료의 접합면에 수직인 균열의 경계요소 해석)

  • 임원균;이현규
    • Computational Structural Engineering
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    • v.9 no.1
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    • pp.93-99
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    • 1996
  • In the particular situations where the crack is terminated at an interface of two materials, the order of stress singularity depends on the elastic constants which specify the properties of two materials. A multidomain boundary element technique is used to solve a crack normal to bimaterial interface. A correct order of shape function is used for displacement by using the isoparametric elements by shifting adequately the side nodes adjacent to this crack tip. A shape function containing the same order of singularity as that in the interface crack is also used for the interpolation of traction. Numerical testing of a binaterial with a crack normal to the interface is carried out with three-node elements. The results obtained are compared with the previous solutions.

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Steady Drift Forces on Very Large Offshore Structures Supported by Multiple Floating Bodies in Waves(II) (다수의 부체로 지지된 초대형 해양구조물에 작용하는 정상표류력(II))

  • J.S. Goo;H.J. Jo;S.Y. Hong;C.H. Lee;K.T. Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.33 no.4
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    • pp.150-161
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    • 1996
  • A numerical procedure is described for predicting steady drift forces on very large offshore structures supported by a large number of the floating bodies of arbitrary shape dimensional source distributing method, the wave interaction theory, the far-field method of using momentum theory and the finite element method for structurally treating the space frame elements. Numerical results are compared with the experimental or numerical ones, which are obtained in the literature, of steady drift forces on a offshore structure supported by the 33(3 by 11) floating composite vertical cylinders in waves. The results of comparison confirmed the validity of the proposed approach.

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Thin Micro-Porous Scaffold Layer on Metallic Substrate (금속기질에 앓은 마이크로 다공질 스케폴드 코팅에 관한 연구)

  • Sin, D.C.;Miao, X.;Kim, W.C.
    • Journal of Power System Engineering
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    • v.14 no.5
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    • pp.41-47
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    • 2010
  • 티타늄과 티타늄 합금은 재료적 특이성 때문에 심장 혈관 임플란트에서 일반적으로 사용되어 왔다. 일찍이 적용된 예로는 인공심장판막, 심박조율기의 보호케이스, 혈액 순환 장치 등이 있다. 하지만 물질유도혈전증(Material-induced thrombosis)은 혈전폐색에 의해 기인한 기능 손실로 심장혈관 임플란트 장치의 주된 합병증으로 존재하고 있으며, 심장혈관 임플란트의 혈전유전자는 심장혈관장치의 발달에 주된 난관 중 하나로 남아있다. 그리고 텍스처 혈액 접합 물질(Textured blood-contacting material)은 1960년대 초반 이후부터 혈액순환 보조 장치의 임상실험에 사용되고 있다. 접합 물질에 내장된 텍스처 섬유조직 표면은 형성, 성장, 안정적 부착, 생물학적 내벽(neointimal layer) 등 유도 혈액(entrapping blood) 성분에 의해 형성된다. 공동(cavity) 형상의 용해 가능한 미립자를 사용하는 SCPL법(Solvent casting/particulate leaching method)은 티타늄 기질 이전에 형성된 폴리우레탄 위에 텍스처(texture)를 생성하기 위해 사용되었다. 또한 콜라겐의 부동화(不動化)에 의한 공동(cavity)은 혈액 접합면에 잔존하기 위한 내피세포를 고정할 수 있는 효과가 있다. cpTi로 층화된 PU 기소공성(microporous)은 구조적 특성과 혈전증 감소를 위한 생물학적 내벽 사용의 잠재성을 평가하기 위한 세포 공동체 실험을 통해서 평가되었다.

RESULTS OF THE TOTAL DOSE EXPERIMENT ON KITSAT-1 (우리별 1호에서의 총 방사선 측정 실험)

  • 이대희;신영훈;민경욱
    • Journal of Astronomy and Space Sciences
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    • v.14 no.1
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    • pp.80-86
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    • 1997
  • High energy particles in the earth's radiation belts cause transient and long term effects on electronic materials, devices, and integrated circuits on board the satellites. Hence, it is very important to have the information on the space radiation environment and the damage on the electronics caused by the se high energy particles. One of the radiation monitor devices frequently used in space is RADFET, a specially designed MOSFET with a thick gate oxide region. The present study focuses on the calibration of RADFET TOT500 using the $Co^{60}{\gamma}-ray$ source. The result shows that the response of RADFET is very sensitive to the change of temperature. The peculiar behavior observed in the TDE (Total Dose Experiment) on board the KITSAT-1 is identified as the thermal effect due to the change in the eclipse rate of the satellite.

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Analysis of Moving Boundary Problem Using Extended Moving Least Squares Finite Difference Method (확장된 이동최소제곱 유한차분법을 이용한 이동경계문제의 해석)

  • Yoon, Young-Cheol;Kim, Do-Wan
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.4
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    • pp.315-322
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    • 2009
  • This paper presents a novel numerical method based on the extended moving least squares finite difference method(MLS FDM) for solving 1-D Stefan problem. The MLS FDM is employed for easy numerical modelling of the moving boundary and Taylor polynomial is extended using wedge function for accurate capturing of interfacial singularity. Difference equations for the governing equations are constructed by implicit method which makes the numerical method stable. Numerical experiments prove that the extended MLS FDM show high accuracy and efficiency in solving semi-infinite melting, cylindrical solidification problems with moving interfacial boundary.

Steady Drift Forces on Very Large Offshore Structures Supported by Multiple Floating Bodies in Waves(I) (다수의 부체로 지지된 초대형 해양구조물에 작용하는 정상표류력(I))

  • H.J. Jo;J.S. Goo;S.Y. Hong;C.H. Lee
    • Journal of the Society of Naval Architects of Korea
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    • v.32 no.4
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    • pp.123-135
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    • 1995
  • A numerical procedure is described for predicting steady drift forces an multiple three-dimensional bodies of arbitrary shape freely floating in waves. The developed numerical approach is based on combination of a three-dimensional source distribution method, wave interaction theory art the far-field method using momentum theory. Numerical results are compared with the experimental or numerical ones, which are obtained in the literature, of steady drift forces on 33(3 by 11) floating composite vertical cylinders in waves. The results of comparison confirmed the validity of the proposed approach. Finally, the interaction effects are examined in the case of an array of 40(4 by 10) freely floating rectangular bodies in shallow water.

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Synthesis and Functional Properties of Plastein from the Enzymatic Hydrolysates of Filefish Protein. 3. Functional Properties of Plasteins (말쥐치육 단백질의 효소적 가수분해물을 이용한 Plastein의 합성 및 그 물성 , 3. Plastein의 기능성)

  • KIM Se-Kwon;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.20 no.6
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    • pp.582-590
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    • 1987
  • Plasteins were synthesized from a peptic filefish protein hydrolysate by papain, $\alpha-chymotrypsin$ and protease(from Streptomyces griceus) under the optimum conditions of previous paper. L-glutamic acid diethylester and L-leucine ethylester were incorporated into plastein during the plastein reaction by papain. The structural changes of freeze-dried filefish meat, peptic hydrolysate, FPC and plasteins were observed by Scanning Electron Microscopy(SEM). The functional properties of plasteins also were measured. The solubility of plasteins was higher than that of FPC and the Glu-plastein had $95\%$ solubility in the range of pH 3-10. The dispersibility of Glu-plastein and protease plastein was similar to that of egg albumin, but those of the other plasteins were lower. The water holding capacity of plasteins was lower than that of egg albumin and C. Lipid absorption of Leu-plastein was tile highest, holding 1.80 ml/g, and that of the other plasteins was similar to that of egg albumin. The emulsifying activity of Leu-plastein was the highest, holding $61.2\%$, and that of Glu-plastein was the lowest, holding $50.7\%$. The emulsifying stability of plasteins was similar to that of the emulsifying activity. The emulsifying capacity of Leu-plastein was 384 ml/g(the highest), but that of Glu-plastein and $\alpha-chymotrypsin$ plastein was 248 ml/g(the lowest). The Leu-plastein shelved the highest foaming capacity, $373\%$. The foaming capacity of other plasteins was higher than that of egg albumin. The foaming stability of plasteins was superior to that of egg albumin. The viscosity of plasteins was lower than that of egg albumin. The microstructure of $\alpha-chymotrypsin$ plastein by SEM wassimilar to that of papain plastein, but other plasteins showed differences in their microstructure. The microstructure of Glu-plastein had a smooth shape.

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The aspect of the revelation of profound secrets of nature in the Poetry of Jo Gyeong[趙璥] and its meaning (조경(趙璥) 시(詩)의 천기유로양상(天機流露樣相)과 그 의미(意味))

  • Ryu, Ho-jin
    • (The)Study of the Eastern Classic
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    • no.49
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    • pp.225-260
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    • 2012
  • The poetry of Haseo Jo Gyeong is first characterized by its fantasy content with mysterious and strange beings such as mountain wizards, gods of flowers, ghosts, Jujos and dragons. Such works imply the huge gap between his political ideal of Neo-Confucianism and the reality of society and are expressions of his resulting sorrow. Of course, he did not just look at reality pessimistically. Like other Neo-Confucianism scholars, he used the symbol of "spring" in his poems, which indicates that he did have optimistic belief in the world in spite of despair. In his poems, the symbol of "spring" implies the political world where the noble man grabbed the power and the sinister groups were extracted or the world where the political ethics of Neo-Confucianism was implemented. His works depicting the essence of natural objects, mountains, and rivers exhibit the characteristics of his poetry more clearly. He described the law of the universe behind natural objects and the vibrant aspects of natural objects by depicting their movements in a clear and sharp manner. Unlike the old Neo-Confucianism scholars that often created poems on the topic of acquirement of natural law and nature, he expanded his poetic world in a direction of revealing the secrets of objects. His works describing the spirit of mountains and rivers are especially noteworthy in that they implied a life attitude of moving forward in an deteriorating world bravely by manifesting strong and dynamic power. Paying attention to the secrets of natural objects, Haseo displayed his life ideal in richer ways by painting the new forms of ume flowers. Unlike the old ume flowers poems in the past, his ume flowers poems present ume flowers as ascetics that obtained truth, men of virtue that inspired contemporary people, or retired gentlemen that revealed the profound secrets of nature. While it is unique that he manifested the forms of ume flowers in ascetics and men of virtue while perceiving the dark reality of society, it is more noteworthy that he described ume flowers as the beings revealing the profound secrets of nature. It was the expression of his yearning for an innocent personality and his fear for losing the personality, clearly depicting a human form of his ego. He created a more human and realistic personality ideal by embracing the contemporary thinking based on the profound secrets of nature in his Dohak poetry[道學詩], which is a significant achievement in that it showed new changes to Dohak poetry in the 18th century.

Analysis on the Figure of Black and White in the Comic Strip which are Mounted on the Book Pages (책 페이지에 구현된 만화의 흑백 연출 의미 분석 - 흑과 백이 갖는 상징성의 조화와 대립을 중심으로)

  • Yun, Bo-Kyoung
    • Cartoon and Animation Studies
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    • s.40
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    • pp.177-209
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    • 2015
  • The purpose of this study is to determine the meaning and function of black and white in the comic strip, which are mounted on the book pages. The role of space in comic strip, compared to the role of time in the cinema, enable to feel the role of the time in the book. Therefore storytelling of comic strip has been placed in the inseparable relationship with space. My aim is to think about the black and white meaning in the visual media, especially the use of black and white which is highlighted in the comic strip. Black and white doesn't mean a loss of color in the comic strip but it works around 2 important notions : readability, modernity (with minimalism). In comic strip, 'black and white' is not a true colour but it is complex items which indicate symbolic significances. Moreover it is also a notion which enhance 'existence and absence' and 'visible and invisible'. That's why to analyze and to understand how the space is organized in comic strip page, i chose several examples extract from black and white comic strip.

Numerical and Experimental Investigation on the Interaction of Subsurface Vortical Flows with a Free Surface (수면하 보오텍스 유동과 자유표면과의 상호 작용에 관한 연구)

  • Mu-Seok Song
    • Journal of the Society of Naval Architects of Korea
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    • v.30 no.2
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    • pp.76-85
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    • 1993
  • In order to predict the free surface signature of turbulent ship wakes two things are essential; a basic understanding of the mechanism of turbulent vortical flow/free surface interactions and a mathematical model to accurately predict the signature. The goal of the study described here is both to supplement experimental work to obtain basic understanding, as well as to condense this understanding in a model(or models) that captures the essential phenomena and thus allows predictions. To do so we followed two main paths guided by experimental observations. One is full simulations of the flow using the clavier-Stokes equations. The other is a vortex modeling, where the vortical structures of the flows are approximated by idealized structures, an the interaction assumed to be essentially inviscid. These approaches complement each other. Full simulations are only applicable to small scale phenomena, where the system is simple, and the Reynolds number is low. The vortex modeling, on the other hand, cannot represent essentially viscous aspects of the problem such as the effect of contamination gradient. Obviously, the modeling is what may eventually lead to a prediction method; the full simulations-too limited to mimic all but the simplest circumstances-are to aid and support the construction of realistic models. We address two-dimensional aspects of the vortex/free surface interaction first. Secondly we obtain some basic understanding of the interaction process through an experiment and then talk about several three-dimensional problems hoping to develop a successful prediction model.

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