• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.5
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• pp.198-201
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• 2005

Carbon nanofibers were formed on silicon substrate which was applied by negative direct current (DC) bias voltage using microwave plasma-enhanced chemical vapor deposition method. Formation of carbon nanofibers were varied according to the variation of the applied bias voltage. At -250 V, we found that the growth direction of carbon nanofibers followed the applied direction of the bias voltage. Based on these results, we suggest one of the possible techniques to control the growth direction of the carbon nanofibers.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.4
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• pp.781-789
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• 1988

The fatigue crack growth and crack closure behavior of long through-thickness cracks and small half-penny shaped surface cracks were investigated in 5083-H113 Aluminum alloy under constant amplitude testing by the unloading elastic compliance method. It was found that, in the Region II, the crack growth behavior of both through-thickness and surface cracks exhibited the tri-linear form with two transitions and no concern with stress ratio R. In the Region I $I_{ab}$ and I $I_{b}$, through-thickness cracks grew faster than surface cracks in length direction, but at .DELTA. K .leq.4 MPa.root.m for R=0.1 the growth rates of surface cracks in depth direction, grew faster than those of through-thickness cracks. When the crack closure was considered, the growth rates of through-thickness cracks lay between the growth rates of depth direction and the growth rates of length direction in surface cracks. It is suspected that this was caused by the difference of crack closure at depth and length direction of surface cracks.s.

• Economic and Environmental Geology
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• v.24 no.3
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• pp.219-226
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• 1991

High quality quartz crystals are grown in 0.5N NaOH + LiOH solution on the seed crystal at $370-395^{\circ}C$ and $1200-1300kg/cm^2$ condition. Growth rates are determined by the crystal thickness grown on the seed crystals with Z(0001) and X($11\bar{2}0$) direction. Relatively high growth rate of Z(0001) direction gradually changes as the temperaure difference (${\Delta}$ Ti) between growth and dissolution zones from 25 to $10^{\circ}C$. The X axis direction is affeced by ${\Delta}$ Ti, and +X($11\bar{2}0$) direction shows a high growth rate than -X($\bar{1}\bar{1}20$) direction. According to the variation with kinds of solutions used, the crystal growth that in NaOH solution is found to be slower than that in $Na_2CO_3$ solution. However, for the case in the NaOH solution mixed with LiOH, it shows a favorable growth rate in terms of grown crystal quality.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.5
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• pp.73-79
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• 2000

The applications of fracture mechanics have traditionally concentrated on cracks loaded by tensile stresses, and growing under an opening or mode I mechanism. However, many cases of failures occur from growth of cracks subjected to mixed mode loading. Several criteria have been proposed regarding the crack growth direction under mixed mode loadings. This paper is aimed at investigation of fatigue crack growth behaviour under mixed mode(I＋II) with variation of angle and pre-crack length in two dimensional branched type precrack. Especially the direction of fatigue crack propagation was predicted and effective stress intensity factor was calculated by finite element analysis(FEA. In this paper, the maximum tangential stress(MTS) criterion was used to predict crack growth direction. Not only experiment but also finite element analysis was carried out and the theoretical predictions were compared with experimental results.

• Journal of the Korean Institute of Rural Architecture
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• v.8 no.1
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• pp.70-79
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• 2006

This study deals with analysing the growth prospect and development direction of Donghae city with two international ports. To do so, it is progressed, firstly, to examine the general discovery about port since the late nineteenth century, secondly, to unfold it's theory with Mukho and Donghae port as Donghae city development element as the central figure, thirdly, to analyse Donghae city as the important place of traffic, the location of industry and the resource base in a spatial planning side.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.1 s.190
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• pp.7-13
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• 2007

• KSBB Journal
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• v.9 no.4
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• pp.412-417
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• 1994

The biodegradable characteristics of starch-filled polyethylene film by fungi were investigated. Aspergillus niger showed the highest cell growth among five species of fungi used in the experiment. Higher starch content gave the higher growth rate of A. niger; however, the kind of film or cutting direction did not give any effects on the cell growth. The use of vinyl trimethoxysilane for the stronger binding of starch and polyethylene did not inhibit the cell growth. When the starch content was higher than 10%, the elongation of the film decreased significantly after the growth of microorganism in the case of transverse direction samples.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.182-187
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• 2000

The application of fracture mechanics have traditionally concentrated on cracks leaded by tensile stresses, and growing under an opening or mode I mechanism. However, many cases of failures occur from growth of cracks subjected to mixed mode loading. Several criteria have been proposed regarding the crack growth direction under mixed mode loadings. This paper is aimed at prediction of fatigue crack growth behaviour under mixed mode(I+II) in two dimensional branched type precrack. In this paper, the maximum tangential stress(MTS) criterion was used to predict crack growth direction. Not only experiment but also finite element analysis(FEA) was carried out. The theoretical predictions were compared with experimental results in this paper

• Journal of Magnetics
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• v.7 no.4
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• pp.147-150
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• 2002

The pinning direction, the spin flop behaviors and the magnetoresistive properties in top synthetic spin valve structure [NiFe/CoFe/Cu/CoFe (t$_{p2}$)/Ru/CoFe (t$_{p1}$)/IrMn] were investigated. The magnetoresistive and pinning characteristics of synthetic spin valves strongly depended on the differences in the two pinning layer thickness, ${\Delta}t(=t_{p2}-t_{p1})$. In contrast to the conventional spin valves, the pinning direction (P1) was canted off with respect to the growth field axis with ${\Delta}t$. We found that the canting angle ${\Phi}$ had different values according to the annealing field direction and ${\Delta}t$. When the samples were annealed at above the blocking temperature of IrMn with zero fields, the canted pinned layer could be set along the growth field axis. Because the easy axis which was induced by the growth field during deposition is still active in all ferromagnetic layers except the IrMn at $250{^{\circ}C}$, the pinning direction could be aligned along the growth field axis, even in 0 field annealing.

• The Korean Journal of Ceramics
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• v.6 no.1
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• pp.53-57
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• 2000

It was observed that the growth rates are different each other in the opposite direction along c-axis due to the crystal polarity. In according to the calculation based on diffusional equations with consideration of the electrical polarization and the surface charge, the difference of growth rates could be explained. Some experiments were compared with this kinetic explanation.