• Proceedings of the Korean Magnestics Society Conference
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• 2004.06a
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• pp.128-129
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• 2004

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.56.1-56
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• 1998

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.118.1-118
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• 2002

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.3
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• pp.105-110
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• 2002

J-aggregates in the mutual mixing LB films of [6Me-DS]$_{1-x}$ [DO]$_{x}$,[DS]$_{1-x}$ [DO]$_{x}$ and [DSe]$_{1-x}$ [DO]$_{x}$ have been studied by optical absorption, fluorescence and surface pressure-area isotherms. In [6Me-DS]$_{1-x}$ [DO]$_{x}$ films, sharp J-band absorption and fluorescence of [6Me-DS] are linearly shifted to the longer wavelength for the replacement of [6Me-DS] by [DO]. According to the x, a smooth shift of the limited area has been cleared. In the [DS]-[DO] system, the J-band is enhanced at 1:1 composition and strong fluorescence is also observed. Also, the presence of phase separation was suggested in the [DSe]-[DO] system, because the absorption spectra were decomposed into [DSe] and [DO] spectra. On the other hand, in the pressure-area isothermal study, reduction in the molecular occupying area of monolayers has been clarified. This could be ascribed to the enhancement of molecular ordering in J-aggregates. These facts are also believed to reflect the most closely packed arrangement of chromophores in the merocyanine dye monolayers. Thus, it was confirmed that the interaction between mixed dye molecules and the CdC1$_2$+KHCO$_3$subphases affected the J-aggregates of the LB films. Also. it is thought that the J-aggregates are formed non-dimensionally in LB films, such as solution synthesized [DX:DO] assemblies on mixing.s on mixing.

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.168.1-168.1
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• 2000

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.159.1-159.1
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• 2000

• Journal of Welding and Joining
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• v.22 no.5
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• pp.26-31
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• 2004

In order to propose the optimum welding condition for field application, the effects of welding heat input and cooling rate at PWHT on the mechanical properties were investigated. Submerged arc welding of 1.25Cr-0.5Mo steel for pressure vessel was conducted at welding heat inputs of 15.2kJ/cm, 30.9kJ/cm, and 44.8kJ/cm, and cooling rates of 184$^{\circ}C$/hr, 55$^{\circ}C$/hr, and 2$0^{\circ}C$/hr at PWHT. From the test results, as the welding heat input increase up to 30.9kJ/cm, the changes of microstructure and impact toughness were small. At the heat input of 44.8kJ/cm, however, toughness decreased obviously due to the coarsening of coarse-grained HAZ and formation of ferrite at bainite grainboundary of weld metal. On the other hand, cooling rates at PWHT did not effect on the changes in microstructure and mechanical properties. Even though tensile strength and impact toughness at all welding conditions of this study were above the minimum specification requirement, it was confirmed that heat input of 30.9kJ/cm was the optimum welding condition to improve welding performance by higher heat input.

• Communications of the Korean Mathematical Society
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• v.33 no.3
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• pp.759-765
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• 2018

We use the finite method developed by C. Athanasiadis based on Crapo-Rota's theorem to give a complete formula for the characteristic polynomial of hyperplane arrangements ${\mathcal{J}}_n$ consisting of the hyperplanes $x_i+x_j=1$, $x_k=0$, $x_l=1$, $1{\leq}i,j,k,l{\leq}n$.

• Journal of Korean Society of Forest Science
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• v.72 no.1
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• pp.9-15
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• 1986

The taxonomy of the broad-leaf evergreen trees (4 genera, 5 species) of Lauraceae was studied by the morphological characteristics of stipules. The results obtained were summarized as follows; 1) The stipules of Lauraceae were arranged alternately with 5-31 stipules of simple leaf. The venations or stipules were basal reticulate and pinnated vein. The shapes of stipule blade were oblong, oblanceolate, rhomboid and oval. The stipule apex was acuminate and obtuse, the stipule base was attenuate, and the stipule margin was entire margin. The trichomes of stipules were sericeous, tomentose and villous. The five species of Lauraceae could be identified by the morphological characteristics of stipules. 2) The morphologically changing forms of stipule vein were classified into three groups; A form - the form of pinnate vein with the distinguished main vein (lozoste lancifolia), B form - the three vein grows into the form of basal reticulate vein (Neolitsea sericea, Cinnamomum japonicum and C. camphora), C form - the parallel vein grows into the form of basal reticulate vein (Marhilus thunbergii). 3) The changing forms of stipule's width from stipule "a" to "j" were three forms; (1) a>d>g>j form: C. japonicum, C. camphora and I. lancifolia, (2) a>cj,(aj,(a

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.519-523
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• 1995

The Fe-TM-C-N nanocrystalline films (TM : Hf, Zr and Nb) are investigated to examine the relation between microstructure and soft magnetic properties. In these films, as the atomic radius of TM element increases, $P_{N2}$ which was added to get good soft magnetic properties was decreased and the maximum value of the permeability shifted to the high Fe range in the composition diagram. The best soft magnetic properties achieved in these films are : Hc of 0.15 Oe, $\mu_{eff}$ of 7800 (1MHz) and $4{\pi}M_{s}$ of 17.5 kG in Fe-Hf-C-N film ; Hc of 0.06 Oe, $\mu_{eff}$ of 2750 (1MHz) and $4{\pi}M_{s}$ of 16.8 kG in Fe-Zr-C-N film and Hc of 0.31 Oe; $\mu_{eff}$ of 2100 (1MHz) and $4{\pi}M_{s}$ of 15.5 kG in Fe-Nb-C-N film. It was considered that the stronger the bonding force between TM and C(N), the finer TM(C,N) phase is precipitated and therefore, the finer $\alpha$-Fe grains are formed. The effective permeability of the Fe-Zr-C-N films and Fe-Nb-C-N films remains nearly constant up to 10 MHz.