• Journal of architectural history
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• v.17 no.4
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• pp.7-23
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• 2008

This study is examine the scales applied to buildings in the age of Unified Silla through construction sites excavated and its results are as follows; First, scales used in the age of Unified Silla were varied like Jucheok, Dangcheok and Hancheok, but it was generally accepted that Dangcheok was used in Yeongjocheok Since it was found that the scales applied to Dabotap at the Bulguksa temple and main building of the Gameunsa temple belonged to Goguryeo, Yeongjocheok scale used early in the age of Unified Silla was transitional and it was thought that Goguryeocheok and Dangcheok were used togethar. Second, according to actual rulers in Korea, china and Japan, the length of Dangcheok(ruler used in Chinese Tang era) mostly belonged to the extent of $29.25cm\;{\sim}\;30.5cm$(central value: 29,71cm). Third, plane features of main building of temple are assumed that it had five rooms in front compartment until the 7th century and then it was diversified to three, five and seven compartment. The size of compartment was same in the scale of front Eokan and Hyeopkan until late 7th century, but since then the dimension of Eokan tended to be wider than Hyeopkan. It was judged that the front Eokan used triple scales like 9, 12, 15, 18 cheok. Fourth, the length of residential structures was 17.5cheok${\sim}$36cheok and Bcheok was commonly used for front side of structure, The length of official structures was 8.4cheok${\sim}$36.3cheok which is similar to residential structures. However it has been confirmed that each of 9cheok, 12cheok, and 15cheok has been used for Eokan and Hyeopkan which gave presumption that triple scales was used for the measure.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.6
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• pp.122-130
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• 1997

An experimental study was conducted to evaluate the bond performance of reinforcing bars embedded in high-strength concrete. Four bond specimens and ten beam splice specimens using concrete with compressive strength of 246kgf/$cm^2$ and 64lkgf/$cm^2$ were tested. The effect of several variables on basic development length and compressive strength of concrete is discussed in splice specimens. The test results showed that the current trend in concrete specification of making the splice length longer to compensate for having smaller cover and spacing may not be an effective approach.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.256-259
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• 2003

The study of confined liquid crystals flourished in the decade of the nineties. Liquid crystals properties have been probed after confinement in well-defined or interconnected geometries as those available in porous media and in polymer networks. In this work we emphasized the power of the nuclear magnetic resonance technique to determine the confined liquid crystal structures. We also present unexpected results on the dependence of the confined liquid crystal configuration on the chain length.

• Journal of Information Display
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• v.4 no.1
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• pp.14-16
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• 2003

The study of confined liquid crystals flourished in the decade of the nineties. Liquid crystals properties have been probed after confinement in well-defined or interconnected geometries as those available in porous media and in polymer networks. In this work we emphasized the power of the nuclear magnetic resonance technique to determine the confined liquid crystal structures. We also present unexpected results on the dependence of the confined liquid crystal configuration on the chain length.

• Journal of information and communication convergence engineering
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• v.9 no.6
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• pp.738-742
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• 2011

This paper has studied drain induced barrier lowering(DIBL) for Double Gate MOSFET(DGMOSFET) using analytical potential model. Two dimensional analytical potential model has been presented for symmetrical DGMOSFETs with process parameters. DIBL is very important short channel effects(SCEs) for nano structures since drain voltage has influenced on source potential distribution due to reduction of channel length. DIBL has to be small with decrease of channel length, but it increases with decrease of channel length due to SCEs. This potential model is used to obtain the change of DIBL for DGMOSFET correlated to channel doping profiles. Also device parameters including channel length, channel thickness, gate oxide thickness and doping intensity have been used to analyze DIBL.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.125-128
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• 2005

Recently new materials, such as fiber reinforced polymer(FRP) and other composite materials are being applied in reinforcing plate or plate or prestressing cables of concrete structures. Although these new materials themselves show the excellent durability and high strength, the bond behaviour between concrete surface and FRP is not well recognized. Therefore, this paper propose a evaluation method for effective bond length between fiber reinforced polymer(FRP) and concrete. To develop the evaluation method, this paper presents a review of current evaluation methods for effective bond length. These methods are compared by single face test, expose merits and demerits. And based on them, new evaluation method was developed. Finally, the new method was compared with existing methods to verify a adequateness for evaluation of effective bond length.

• Journal of Ocean Engineering and Technology
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• v.9 no.1
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• pp.83-91
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• 1995

Surface defects in structural members are apt to be origins of fatigue cracks growth, which may cause serious failure of whole structures. Most structure has a part where stress concentrates such as welded joints, corner parts, etc. And then, analysis on crack growth and penetration from these defects, therefore, is one of the most important subjects for the reliability of LBB design. The present paper has performed an experimental and analysis on the fatigue crack propagation by variety in crack length of surface cracked plate with stress concentration part. The crack growth behavior can be explained quantitatively by using Newman-Raju equation and the stress partitioning method proposed by ASME B&P Code Sec. XI. The stress concentration factor $K_t$ has affected on the crack growth. The crack growth after penetration depends upon the initial front side crack length.

• Computers and Concrete
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• v.22 no.1
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• pp.39-51
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• 2018

This study introduces a new algorithm to determine size independent values of fracture energy, fracture toughness, and fracture process zone length in three-point bending specimens with shallow to deep notches. By using the exact beam theory, a concept of equivalent notch length is introduced for specimens with no notches in order to predict the peak loads with acceptable precisions. Moreover, the method considers the variations of fracture process zone length and effects of higher order terms of stress field in each specimen size. In this paper, it was demonstrated that the use of some recently developed size effect laws raises some concerns due to the use of nonlinear regression analysis. By using a comprehensive fracture test data, provided by Hoover and Bazant, the algorithm has been assessed. It could be concluded that the proposed algorithm can facilitate a powerful tool for size effect study of three-point bending specimens with different notch lengths.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.806-811
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• 2004

Currently, in the design criteria for the high speed railway bridges, the maximum distance between bridge expansion joint is limited to 80m using a continuous welded mil, in order to limit the additional stress in the rail due to the rail-bridge interaction. In the past study on the resonance effect of HSR train, it is known that the reduction of resonance and dynamic responses of bridge deck occurs at the specific expansion length of 28.05m and 46.75m. In this study, the stability of track structure on the HSR bridges with expansion length of 90m has checked by finite element method. And the track behavior including mil stresses and relative displacements are compared to the current state of track structures on the bridge system with 80m long expansion length.

• Structural Engineering and Mechanics
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• v.74 no.2
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• pp.215-225
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• 2020

Thin films easily wrinkle under compressive loading due to their small bending stiffness resulting from their tiny thickness. For a thin film deposited on a functionally graded substrate with non-uniform stiffness exponentially changes along the length span in this paper, the uniaxial wrinkling problem is solved analytically in terms of hyper-Bessel functions. For infinite, semi-infinite and finite length systems the wrinkling load and wrinkling wavenumber are determined and compared with those in literature. In comparison with a homogeneous substrate-bounded film in which the wrinkling pattern is uniform along the length span, for a functionally graded substrate-film system the wrinkles accumulate around the softer location of the functionally graded substrate. Therefore, the effective length of the film influenced by the wrinkles decreases, the amplitude of the wrinkles on softer regions of the functionally graded substrate grows and the wrinkling load of the functionally graded substrates with higher softening rate decreases more. The results of the current research are expected to be useful in science and technology of thin films and wrinkling of the structures especially living tissues.