• Computational Structural Engineering
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• v.9 no.2
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• pp.153-161
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• 1996

In this paper, theory of fracture mechanics for the pressurized thermal shock is investigated and numerical procedure for the evaluation of the pressure vessel under pressurized thermal shock is developed. For the given material properties, transient history such as temperature and pressure, and postulated flaw, the stress distribution is obtained to calculate stress intensities for a wide range of assumed crack sizes. The stress intensities are compared with the material fracture toughness values corresponding to the chemical compositions and the distribution of the nil ductility transition temperature, to determine the crack growth during the transient. Plant-specific calculations have been performed for several transients and the evaluation results are discussed.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.203-203
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• 2003

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.80-84
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• 2000

A mesh superposition technique is presented for an efficient analysis of structural behavior. Refined child mesh is superimposed over parent elements for the region of interest. It is a kind of adaptive mesh refinement, which allows locally refined mesh without introducing transition region or multipoint constraints. Proper boundary condition is necessary to avoid redundant rigid body motion and kinematic compatibility between neighbor elements. Delamination buckling analysis is conducted to demonstrate accuracy and efficiency of the present method.

• Proceedings of the Korea Society of Design Studies Conference
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• 2000.11a
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• pp.128-129
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• 2000

말없는 마차와 같은 형태에서 출발한 자동차는 21세기를 여는 현 시점에서 완성된 틀의 정점에 서서 새로운 전기를 맞이하고 있다. 기존의 틀을 벗어난 새로운 레이아웃의 차량들이 소개되고 있으며 차량용 정보통신기기와 무인주행기술의 발달로 자동차 디자인은 새로운 국면을 맞이하고 있다. (중략)

• Journal of Magnetics
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• v.1 no.2
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• pp.57-59
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• 1996

The YBa$_2$Cu$_3$O6+xstructures have been fluorinated by a gas phase exchange technique, and 19F NMR was used to identify the structural fluorine. Magnetic susceptibility measurements showed that the fluorination turned a marginally nonsuperconducting sample into a 40 K superconductor, as well as that it raised the onset of the superconducting transition of the 60 K superconductor YBa$_2$Cu$_3$O6.7 to about 100 K.

• Journal of the Korean Ceramic Society
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• v.22 no.4
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• pp.3-8
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• 1985

The layer charge densities and interlayer C. E. C(cation exchange capacity) of ten mica-type aluminosilicates from Yong-il Pohang-prefacture were determined by n-alkylammonium method which is based on the mo-nolayer-doubelelayer structural transition of ni-alkylammonium ion in interlayer space of the layered silcates. The upper and lower limits of layer charge and interlyer C, E, C estimated were about 0.25~0.36 eq/(Si, $Al)_4$ O10 and 69~99meq/100g, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1351-1354
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• 2005

We report on the photoalignment process of pentacene thin film with optical anisotropy on treated buffer layers. The photopolymer, showing an anchoring transition, was used as a buffer layer to control the structural order of the pentacene molecules. Using the photoelastic modulator, it was found that the grain size and the optical anisotropy of the pentacene thin film were strongly correlated with each other.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.476-481
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• 1991

This paper investigates the relationship between the two problems, supervisor reduction and observation function (projection) design, which arise in supervisory control of DEDS. It is shown through an example that a reduced supervisor of minimal size does not necessarily result in a maximal projection when a projection design method which uses the transition structure of a supervisor is applied. Also, if an L-realizable projection P is available and if a supervisor has a special structural feature, a cover C for supervisor reduction can be easily obtained. By investigating the control-compatibility of states of the reduced supervisor based on C, we can also check maximality of P in a simple manner.

• The Korean Journal of Rheology
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• v.2 no.1
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• pp.53-59
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• 1990

물량 및 촉매를 변화시키며 TEOS 용액에 대하여 점도를 측정하였다. 염기성 촉매 를 사용한 TEOS 용액은 구형 입자를 갖는 것으로 나타났다. 적은 초기 물량과 산성 촉매 를 사용한 TEOS 용액은 환원 점도의 실험결과로 미루어 선형의 고분자를 갖고 있는 것으 로 보인다. 반면 많은 물량과 산성폭매를 사용한 TEOS 용액은 많은 가지 사슬을 갖는 비 선형 입자를 형성하는 것으로 사료된다. 적은 물량의 산성촉매에서 생성하는 선형고분자 구 조느 삼중규소연쇄의 리본형태로 생각된다.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2005.04a
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• pp.68-69
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• 2005