• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.305-306
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• 2005

• Magazine of the Korea Concrete Institute
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• v.19 no.3
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• pp.69-73
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• 2007

• Proceedings of the KSR Conference
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• 2006.05b
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• pp.388-399
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• 2006

• Journal of the Korean Statistical Society
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• v.22 no.1
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• pp.93-111
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• 1993

Let ${X(t) : t \geq 0}$ be a real-valued stochastics process with stationary independent increments. In this paper, under the condition of stochastic compactness, we obtain appropriate function $\alpha(t)$ and random function $\beta(t)$ such that for some positive finite constant C, lim sup${X(t) - \alpha(t)}/\beta(t) = C$ a.s. both as t tends to zero and infinity.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.263.2-263.2
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• 2001

• Analytical Science and Technology
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• v.28 no.3
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• pp.236-245
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• 2015

Recently, candles have been widely used to create a romantic atmosphere and to heat tea. In this study, a small combustion chamber for candle was designed using an 0.008 m³ bell jar. The emission factors of combustion products were then measured. The combustion chamber includes a glass dish, which prevents candle flame from affecting the composition of the gas emitted through the exhaust outlet. The outlet in the combustion chamber was designed as a cone shape, and it was lengthened to prevent flow from the outside, which could affect the homogeneous composition of the exhaust gas. The temperature at the outlet of the chamber was 34 ℃~41℃. The major combustion products of the candle, such as such aldehydes and acids, contained oxygen. The mass specific emission rates of benzene, toluene, ethylbenzene, and TVOC were 0.04 μg/g, 0.01 μg/g, 0.02 μg/g, and 3.81, respectively. The mass specific emission rates of formaldehyde, acetaldehyde and benzaldehyde were 4.48 μg/g, 1.09 μg/g, and 0.67 μg/g, respectively. Considering the different compositions of the candle samples, their mass specific emission rates were similar to those obtained by using a large chamber 0.17 m³~50 m³ in size.

• Journal of Conservation Science
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• v.38 no.2
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• pp.117-123
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• 2022

In this study, investigated the possibility of quantitatively and qualitatively analyzing Korean ancient glasses via Raman Spectroscopy. We subjected four categories of Korean traditional glasses, namely, lead-BaO, lead, potash, and soda glasses (3, 3, 10, and 10 pieces, respectively), to this analytical technique. The results showed significant differences between the stretching and bending Raman vibration regions corresponding to these different Korean ancient glass types. Specifically, the stretching vibration regions corresponding to lead-BaO and lead glasses showed peaks at 1040 and 1000 cm^-1, respectively; the stretching vibration region of normal glass appears at 1100 cm^-1. The bending vibration regions corresponding to potash and soda glass showed Raman peaks at 490 and 560 cm^-1, respectively. Furthermore, the Raman spectra of the lead and lead-BaO glasses showed red shifts, which depended on the amount of PbO present. Thus, our findings highlighted the possibility of quantitatively determining the amount of PbO, a major component of lead glasses, via Raman Spectroscopy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.3
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• pp.249-254
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• 2023

La_0.7-xCe_xSr_0.3MnO₃ specimens were fabricated by a solid state reaction method and structural and electrical properties with variation of Ce⁴⁺ contents were measured. All specimens exhibited a polycrystalline rhombohedral crystal structure, and the (110) peaks were shifted to low angle side with increasing the amount of Ce⁴⁺ contents. As Ce⁴⁺ ions with different ion radii and charges are substituted with La³⁺ ions, electrical properties are thought to be affected by changes in the double exchange interaction between Mn³⁺-Mn⁴⁺ ions due to distortion of the unit lattice, a decrease in oxygen vacancy concentration, and an increase in lattice defects. Resistivity gradually decrease as the amount of Ce⁴⁺ added increased, and negative temperature coefficient of resistance (NTCR) properties were shown in all specimens. In the La_0.5Ce_0.2Sr_0.3MnO₃ specimens, electrical resistivity, TCR and B-value were 31.8 Ω-cm, 0.55%/℃ and 605 K, respectively.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.456-462
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• 2016

$NaCaGd(MoO_4)_3:Ho^{3+}/Yb^{3+}$ ternary molybdates were successfully synthesized by microwave sol-gel method for the first time. Well-crystallized particles formed after heat-treatment at $900^{\circ}C$ for 16 h showed a fine and homogeneous morphology with particle sizes of $3-5{\mu}m$. Under excitation at 980 nm, the UC intensities of the doped samples exhibited strong yellow emissions based on the combination of strong emission bands at the 520-nm and 630-nm emission bands in the green and red spectral regions, respectively. The strong 520-nm emission band in the green region corresponds to the $^5S_2/^5F_4{\rightarrow}^5I_8$ transition of $Ho^{3+}$ ions, while the strong 630-nm emission band in the red region appears to be due to the $^5F_5{\rightarrow}^5I_8$ transition of the $Ho^{3+}$ ions. The optimal $Yb^{3+}:Ho^{3+}$ ratio was found at 9:1, as indicated by the composition-dependent quenching effect of $Ho^{3+}$ ions. The pump power dependence of the upconversion emission intensity and the Commission Internationale de L'Eclairage chromaticity coordinates of the phosphors were evaluated in detail.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.474-478
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• 2005

Craniosynostosis is a congenital anomaly characterized by premature closure of cranial sutures. Surgical intervention should be performed during infancy. However, surgical correction of craniosynostosis remains bone defect and secondary angle occasionally. Currently, publications investigating solutions to bone defect and secondary angle created by cranioplasty are getting much interest. We have used $BoneSource^{(R)}$ which is relatively safe as an implantable substance for providing solutions for this problem. From June 2002 to January 2004, five children with craniosynostosis underwent frontocalvarial contouring using $BoneSource^{(R)}$ and concurrent cranial vault remodeling. The patient ages ranged from 8.0 months to 4.9 years(mean, 2.5 years). The quantity of $BoneSource^{(R)}$ implanted ranged from 10 to 25g, with a mean of 13g. This paper presents the first series of children treated with $BoneSource^{(R)}$ for frontocalvarial contouring in the surgical correction of craniosynostosis. No patients experienced any complications. Our results shows excellent retention of contour without causing asymmetry or irregularity. No visible evidence of interference with craniofacial growth were observed. Through our experiences, $BoneSource^{(R)}$ is found to be very useful for frontocalvarial contouring in children undergoing correction of craniosynostosis.