• Journal of Korea Foundry Society
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• v.35 no.6
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• pp.163-169
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• 2015

This study reports the influence of gadolinium (Gd) addition on mechanical and corrosion properties of 2205 duplex stainless steel. In all alloys produced, regardless of the initial Gd content, Gd-based inclusions were well distributed in the duplex stainless steel matrix. As the Gd content increased from 0 wt% to 0.19 wt%, the ultimate tensile strength and hardness of the alloy increased from 630 MPa to 977 MPa and from 57 to 61, respectively, while elastic modulus, tensile elongation and impact energy of the alloy decreased. The critical crevice temperatures of Alloy1, Alloy2 and Alloy3 were $20^{\circ}C$, $20^{\circ}C$ and $15^{\circ}C$, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1607-1610
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• 2005

A new configuration of LCD projectors for polarized stereoscopic projection having no light loss in the polarization process is suggested. In the proposed system, two polarizing filters that are employed in the conventional LCD polarized stereoscopic projection system causing additional light loss and image distortion are excluded by taking into account of polarization property of the LCD projector and image processing techniques. From some experimental results by using the Type-1 LCD projectors, light loss of the proposed system occurring in the polarization process is found to be zero.

• Kyungpook Mathematical Journal
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• v.56 no.1
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• pp.69-81
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• 2016

For a positive integer k, a k-rainbow dominating function of a digraph D is a function f from the vertex set V (D) to the set of all subsets of the set $\{1,2,{\ldots},k\}$ such that for any vertex $v{\in}V(D)$ with $f(v)={\emptyset}$ the condition ${\cup}_{u{\in}N^-(v)}$ $f(u)=\{1,2,{\ldots},k\}$ is fulfilled, where $N^-(v)$ is the set of in-neighbors of v. A set $\{f_1,f_2,{\ldots},f_d\}$ of k-rainbow dominating functions on D with the property that $\sum_{i=1}^{d}{\mid}f_i(v){\mid}{\leq}k$ for each $v{\in}V(D)$, is called a k-rainbow dominating family (of functions) on D. The maximum number of functions in a k-rainbow dominating family on D is the k-rainbow domatic number of D, denoted by $d_{rk}(D)$. In this paper we initiate the study of the k-rainbow domatic number in digraphs, and we present some bounds for $d_{rk}(D)$.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.135-143
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• 2013

In this study, we suggested effective countermeasure of biodiesel oxidation problems by investigating the oxidation degradation of biodiesels derived from variable resources and the level of oxidation stability of current distributing biodiesel blended fuels (2%) in Korea, and oxidation stability change according to storage time (for 3 month) and biodiesel blending ratio (2, 5, 7, 10%). By the composition analysis results of biodiesel from various resources which are possible to distribute in Korea, the biodiesel from animal fat has poor oxidation stability and cold performance, while the biodiesel from coconut and palm kernel which are considered as future potential raw material showed good oxidation stability and cold performance. The oxidation stability level of current distributing biodiesel blended fuels in Korea was excellent with showing over 30 hours (average 68 hours) stability, but the oxidation stability of the blended fuel with animal fat biodiesel having poor oxidation property (1.22 hours) was rapidly decreased to below 32 hours by mixing only 2%. Therefore, we have to pay attention to quality control of oxidation property, because the oxidation stability problem can be caused by increasing biodiesel blending ratio and diversifying raw materials those have worse property.

• Journal of the Korea Computer Graphics Society
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• v.13 no.3
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• pp.19-24
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• 2007

In this paper, we describe a method of defining an object's real length in order to compare objects' lengths precisely using all real length units in the real world. The browser in our study represents an object's length by referencing to the physical length property defined at modeling when it displays the object. Since objects' lengths are appropriately scaled according to these units, objects can be precisely and visually compared in sire using real world length units. The concept of defining the real length unit is extended to the X3D specification. The units are ranged from $10^{-24}(yotta)\;to\;10^{24}(yocto)$. In addition, we explain the method for processing LOD (Levels Of Detail) and for applying the property of LOLD (Levels of Length Detail) when objects with different LOLD are read into the browser.

• Journal of applied mathematics & informatics
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• v.31 no.1_2
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• pp.241-246
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• 2013

Choi [1] identified and characterized the limiting diffusion of this diploid model by defining discrete generator for the rescaled Markov chain. In this note, we define the operator of projection $S_t$ on limiting diffusion and new measure $dQ=S_tdP$. We show the martingale property on this operator and measure. Also we conclude that the martingale problem for diffusion operator of projection is well-posed.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2839-2842
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• 2014

• Proceedings of the Korean Vacuum Society Conference
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• 2007.08a
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• pp.374-374
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• 2007

• Analytical Science and Technology
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• v.24 no.2
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• pp.105-112
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• 2011

Syntheses and property analysis of hydropolysilanes were studied. Those hydropolysilanes can be utilized as precursors for amorphous silicon and polycrystallline silicon for the purpose of the solar cell and the thin film transister for the next generation's semiconductors. Most important characteristics of this study are to find optimized conditions for the synthesis and property analysis of soluble hydropolysilanes. Also the possibility of pyrolytic conversion to amorphous and polycrystalline silicon was investigated.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.556-560
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• 2009

Aggregation behavior of three kinds of benzindocarbocyanine dyes in aqueous methanol solution was studied by UV-Vis absorption spectrum. The results indicated that the three dyes all existed monomer-dimer equilibrium in aqueous methanol solution (concentration range $10^{−5}\;to\;10^{−6}$ M) at 25.0$\sim$41.0 ${^{\circ}C}$ for Dye 1, 28.0$\sim$49.0 ${^{\circ}C}$ for Dye 2 and 26.0$\sim$47.0 ${^{\circ}C}$ for Dye 3. The fundamental property of the three dyes as the dimeric association constant KD, the dimeric free energy ${\Delta$}G_D, the dimeric entropy ${\Delta$}S_D, and the dimeric enthalpy ${\Delta$}H_D were determined. The ${\Delta$}H_D of three dyes: Dye 1, Dye 2 and Dye 3 was -42.5, -15.1 and -18.9 kJ/mol, respectively. The experimental observations were the subject of a theoretical study including the ground-state geometries which were fully optimized using DFT at B3LYP/6-31G level. The effect of dye molecule structure on ${\Delta$}H_D was discussed by theoretical calculations.