• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.127-132
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• 1993

Ten-week-old White Leghorn immature males and females were exposed to four lighting regimens: a constant light (12L : 12D); repeated up and slow down (13 min. up and 1 min. down per day for 13 consecutive days, and repeated on two-week cycle) lighting; repeated slow up and down (1 min. up per day for 13 consecutive days and 13 min. down, and repeated on two-week cycle) lighting; and step-up (14 min. up every second week) lighting. At 15 weeks of age, significantly larger testis and comb weights and significantly higher concentrations of plasma LH and testosterone were observed in the cockerels under the repeated slow up and down lighting regimen than those under the other lighting regimens. At 20 weeks of age, significantly larger oviduct weights and significantly higher concentrations of plasma estradiol were observed in the pullets under the repeated up and slow down, and the step-up lighting regimens than those under the other lighting regimens.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.6
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• pp.759-766
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• 2018

Although the Act on the Prevention of Light Pollution Due to Artificial Lighting has been enforced since 2013, the area of advertisement lighting has made slow progress in solving the problems of light pollution. This paper first investigated institutional problems by analyzing domestic laws and regulations relating to the light pollution of advertisement lighting, and investigated and analyzed methods for reducing light pollution that were applied in overseas countries. Then, problems of light pollution were analyzed by conducting a research on the actual status of advertisement lightings installed in South Korea and applying various methods for reducing light pollution, and advertisement lighting using LED was recommended. As a method for reducing light pollution that can be applied to the process of manufacturing channel letter-type advertisement lights, power consumption per unit area ($W/m^2$) was proposed, and $100W/m^2$ was recommended as a value currently suitable for South Korea.

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.407-408
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• 2008

본 논문에서는 광밀도가 매우높은 물질에서 단일광펄스에 의한 느린빛 현상을 관측하였다. 본 실험결과와 기존의 다른 방식에 의한 느린빛 현상의 장/단점을 비교 검토한다. OCIS: Coherent optical effects (020.1670)

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.623-627
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• 2000

Aggregation of hydrophobically end-capped poly(ethylene oxide)s: HEURs, denoted as $C_8$$EO_{380}$$C_8$, $C_12$$CO_{600}$$C_{12}$, and $C_{18}$$EO_{860}$$C_{18}$,are described using static fluorescence, dynamic light scattering, and atomic force microscope (AFM) techniques. The CAC (critical aggregation concentration) was determined by com-paring two fluorescent peaks which were influenced by the polarity of the probe dye molecules, pyrene. The aggregation occurs in concentrations higher than 10 g/L of $C_8$$EO_{380}$$C_8$ and the CAC decreases by increasing the side chain length. The dynamic light scattering experiment shows fast mode and slow mode decays, and both are diffusive. The fast mode does not depend on the concentration, but the slow mode shows concentration dependence influenced by the formation of an aggregated structure. The hydrophobic end groups effect more dominantly than the main chains for the formation of HEUR micelles. By increasing the concentration, the HEUR micelles change their structure from spheres to rodlike micelles, and finally make fused structures, which were visualized with atomic force microscopy.

• Nuclear Engineering and Technology
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• v.35 no.2
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• pp.154-164
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• 2003

The explicit consideration of different pressurization rates in estimating the probabilities of containment failure modes has a profound effect on the confidence of containment performance evaluation that is so critical for risk assessment of nuclear power plants. Except for the sophisticated NUREG-1150 study, many of the recent containment performance analyses (through Level 2 PSAs or IPE back-end analyses) did not take into account an explicit distinction between slow and fast pressurization in their analyses. A careful investigation of both approaches shows that many of the approaches adopted in the recent containment performance analyses exactly correspond to the NUREG-1150 approach for the prediction of containment failure mode probabilities in the presence of fast pressurization. As a result, it was expected that the existing containment performance analysis results would be subjected to greater or less conservatism in light of the ultimate failure mode of the containment. The main purpose of this paper is to assess potential conservatism of a plant-specific containment performance analysis result in light of containment failure mode probabilities.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.385-391
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• 2010

This study was conducted to compare proteins expressed in M. longissimus from Hanwoo and Holstein steers immediately after slaughter. Two-dimensional electrophoresis (2DE)/LC-MS/MS analysis revealed that the total number of detectable protein spots from longissimus muscle tissues was slightly higher in Hanwoo ($575{\pm}65$) than Holstein ($534{\pm}13$) steers, but that these numbers were not statistically significant due to large variation between replicates. A total of twelve protein spots did not match between sample groups, eight of which were expressed in the Hanwoo sample and four that were expressed in the Holstein sample. The protein spots detected in the Hanwoo sample included smooth muscle and non-muscle myosin alkali light chain 6B isomers, ${\alpha}B$ crystallin isomers, hemoglobin ${\beta}$-A chains, slow myosin heavy chains, and slow skeletal muscle troponin T chains. Collectively, these proteins are a class of slow-twitch muscle fiber and mirror that Hanwoo muscle tissue sampled for the current study contained more slow-twitch muscle fibers than Holstein one. Conversely, proteins detected from the Holstein sample included ankyrin repeat domain 2 and creatin kinase isomers. Given that creatin kinase isomers are related to the fast-twitch muscle, these results likely indicate that Holstein muscle tissue sampled for the current study contained more fast-twitch muscle fibers than Hanwoo beef.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.545-548
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• 1999

The electro-optical characteristics of photo-aligned vertical-alignment (VA)-liquid crystal display (LCD) with non-polarized ultraviolet (UV) light irradiation of 45\`on homeotropic polyimide (Pl) surface were investigated. LC alignment on photo-aligned VA-LCD is attributed to photo-depolymerized reaction of the polymer with non-polarized UV light irradiation on PI surface. We had good voltage-transmittance (V-T) characteristics of photo-aligned VA-LCD. The response time of photo-aligned VA-LCD was slower than that of the rubbing-aligned VA-LCD. Finally, we suggest that the slow response time of photo-aligned VA-LCD depends on the LC domain.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.2
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• pp.161-164
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• 2019

This study describes the development of graphene-$TiO_2$ conjugates for the enhancement of the photocatalytic efficiency of $TiO_2$. Graphene-based hybrid nanomaterials have attracted considerable attention because of the unique and advantageous properties of graphene. In the proposed hybrid nanomaterial, graphene serves as an electron acceptor to ensure fast charge transfer. Effective charge separation can, therefore, be achieved to slow down electron-hole recombination. This results in an enhancement of the photocatalytic activity of $TiO_2$. In addition, increased adsorption and interactions with the adsorbed reagents also lead to an improvement in the photocatalytic activity of graphene-$TiO_2$ hybrid nanomaterials. The acquired result is encouraging in that the photocatalytic activity of $TiO_2$ was initiated using visible light (630 nm) instead of the typical UV light.

• BMB Reports
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• v.38 no.1
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• pp.104-110
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• 2005

We extended the measurable time scale of DNA dynamics to microsecond using $[Ru(phen)_2(dppz)]^{2+}$ (phen = 1,10-phenanthroline, dppz = dipyrido[3,2-a:2',3'-c]phenazine) (RuPD), which displays a mean lifetime near 500 ns. To evaluate the usefulness of this luminophore (RuPD) for probing nucleic acid dynamics, its intensity and anisotropy decays when intercalated into supercoiled and linear pBluescript (pBS) II SK(+) phagemids were examined using frequency-domain fluorometry with a blue light-emitting diode (LED) as the modulated light source. The mean lifetime for the supercoiled phagemids (< $\tau$ > = 489.7 ns) was somewhat shorter than that for the linear phagemids (< $\tau$ > = 506.4 ns), suggesting a more efficient shielding from water by the linear phagemids. The anisotropy decay data also showed somewhat shorter slow rotational correlation times for supercoiled phagemids (997.2 ns) than for the linear phagemids (1175.6 ns). The slow and fast rotational correlation times appear to be consistent with the bending and torsional motions of the phagemids, respectively. These results indicate that RuPD can have applications in studies of both bending and torsional dynamics of nucleic acids.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.3
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• pp.199-203
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• 2017

Hot embossing techniques are used to engrave patterns on plastic substrates. Roll based hot embossing uses a heated roll for a continuous process. A heated roll with relief patterns is impressed on a preheated plastic substrate. Then, the substrate is cooled down quickly to prevent thermal shrinkage. The roll speed is normally very slow to ensure substrate temperature increase up to the glass transition temperature. In this paper, we propose a noncontact preheating technique using focused infrared light. The infrared light is focused as a line beam on a plastic substrate using an elliptical mirror just before entering the hot embossing roll. The mid range infrared light efficiently raises the substrate temperature. For preliminary tests, substrate deformation and temperature changes were monitored according to substrate speed. The experiments show that the proposed technique is a good possibility for high speed hot embossing.