• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.606-613
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• 2003

This study investigated the effects of food type (condensed freshwater Chlorella, dried Chlorella, dried Spirulina, dried Schizochytrium, baker's yeast and $\omega-yeast$) and amount, and supplementation of vitamin $B_{12}$ on the growth of freshwater rotifer (Brachionus calyciflorus) in high density culture. Growth of rotifers fed condensed freshwater Chlorella was the highest and its density ranged $7.65-8.14{\times}10^3\;inds./mL.$ The primary lipid acids of rotifers fed condensed freshwater Chloyella were linoleic and linolenic, and their amount ($\%$ of total fatty acids) were $48.8\%\;and\;26.8\%,$ respectively. This suggests that condensed freshwater Chlorella would be an effective diet for high quality and quantity rotifers, which in turn serve as live food for freshwater fish larvae. Growth rate of rotifers with Chlorella supplementation increased as amount of supplementation increased up to 1.5 and 2.5 mg at 28 and $32^{\circ}C$, respectively. However, undissolved ammonia toxicity and packing volume of Chlorella in culture medium, reached the optimal conditions for the stable and effective cultivation of rotifers when amount of condensed freshwater Chlorella was 1.5 mg in dry weight per 1,000 rotifers at $28^{\circ}C\;and\;32^{\circ}C$ Growth of rotifers in condensed freshwater Chlorella with vitamin $B_{12}$ supplementation was significantly higher than that of rotifers without supplementation. However, no significant difference was found among the different concentrations of vitamin $B_{12}.$ Therefore, vitamin $B_{12}$ could improve the growth of rotifers (B. calyciflorus).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.7
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• pp.606-610
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• 2007

This paper describes the Raman scattering characteristics of polycrystalline (poly) 3C-SiC thin films, in which they were deposited on the oxidized Si substrate by APCVD method according to growth temperature. Since the phonon modes were not measured for $0.4{\mu}m$ thick 3C-SiC, $2.0{\mu}m$ thick 3C-SiC deposited on the oxidized Si at $1180^{\circ}C$, in which TO (transverse optical mode) and LO (longitudinal optical mode) phonon modes were appeared at 794.4 and $965.7cm^{-1}$, respectively. The broad FWHM (full width half maximum) can explain that the crystallinity of 3C-SiC deposited at $1180^{\circ}C$ becomes polycrystalline instead of disorder crystal. Additionally, the ratio of intensity $I_{LO}/I_{TO}{\approx}1.0$ of 3C-SiC indicates that the crystal disorder of $3C-SiC/SiO_2/Si$ is small. Compared poly $3C-SiC/SiO_2$ with $SiO_2/Si$ interfaces, $1122.6cm^{-1}$ phonon mode was measured which may belong to C-O bonding and two phonon modes, 1355.8 and $1596.8cm^{-1}$ related to D and G bands of C-C bonding in the Raman range of 200 to $2000cm^{-1}$.

• Korean Journal of Child Education & Care
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• v.19 no.2
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• pp.57-69
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• 2019

Objective: The purpose of this research was to examine the moderating effects of relationships on the association between temperament and peer play interaction. Methods: The participants were 606 four year olds who were recruited from day care centers and preschools located in Incheon and Gyeonggi province. Teacher-child relationship was measured with Student-Teacher Relationship Scale. Peer interactions were measured with Penn Interactive Peer Play Scale. Temperament was measured with Child Behavior Questionnaire (CBQ). The data was analysed using Pearson correlation and hierarchial regression. Results: Teacher-child intimacy moderated the associations between inhibitory control and play disruption as well as between emotionality and play disconnection. Moreover, Teacher-child conflict moderated the association between emotionality and play disconnection. Conclusion/Implications: The findings suggest that teacher-child relationships buffer risks conferred by temperament.

• Journal of Broadcast Engineering
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• v.23 no.5
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• pp.606-613
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• 2018

This study is concerned with implementing an external memory expansion device for large-scale image processing. It consists of an external memory adapter card with a PCI(Peripheral Component Interconnect) Express Gen3 x8 interface mounted on a graphics workstation for image processing and an external memory board with external DDR(Dual Data Rate) memory. The connection between the memory adapter card and the external memory board is made through the optical interface. In order to access the external memory, both Programmable I/O and DMA(Direct Memory Access) methods can be used to efficiently transmit and receive image data. We implemented the result of this study using the boards equipped with Altera Stratix V FPGA(Field Programmable Gate Array) and 40G optical transceiver and the test result shows 1.6GB/s bandwidth performance.. It can handle one channel of 4K UHD(Ultra High Density) image. We will continue our study in the future for showing bandwidth of 3GB/s or more.

• Fashion & Textile Research Journal
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• v.21 no.5
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• pp.606-617
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• 2019

The present study newly developed a firefighters' protective jacket and pants using a Nomex honeycomb structured layer (HPC) in cases of being exposed to flashover or flameover. This study evaluated the protective and comfort functions of an HPC compared to the current KFI firefighters' protective clothing (FPC). The results are as follows. First, thermal protective performance (TPP) of fabric layers was 2.75 times greater for HPC than FPC at $125kW/m^2$. Second, the predicted second and third degree burn areas were smaller for HPC than FPC when using a flame manikin. Third, thermal insulation using a thermal manikin was 0.2 clo greater for HPC than FPC. Fourth, there were no marked differences in maximal performance, mobility, and microclimate temperature/humidity between FPC and HPC through human wear trials. The thermal insulation of HPC was higher than that of FPC; however, any negative effect of HPC thermal insulation on the comfort functions for firefighters was not found. In conclusion, the newly-developed HPC provided more protection in reducing burn injuries from $125kW/m^2$, while no negative impact on maximal performance, mobility and thermal comfort functions of firefighters, which is appropriate for quick-evasive tactics at the flashover, flameover or back draft fires.

• Journal of Broadcast Engineering
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• v.19 no.5
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• pp.606-615
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• 2014

This paper is to propose an algorithm for digital hologram watermarking by using a characteristic of the Fresnel diffraction model in 2D image. When 2D image is applied Fresnel transform, the result concentrates center region. When applied to a hologram, on the other hand, the result focused diffraction pattern of 2D form. Using this characteristic, to generate diffraction model by applying 2-th Fresnel transform to the hologram. Corner of diffraction model is mark space. This mark space is embedded watermark and extracted watermark. Experimental results showed that all the extracted watermarks after several kinds of attacks (Gaussian blurring, Sharpening, JPEG compression) showed visibilities good enough to be recognized to insist the ownership of the hologram.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.249-254
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• 1993

N-p-nitrophenyl poly(m-phenylene isophthalamide) was obtained from treatment of poly(m-phenylene isophthalamide) with sodium hydride in dimethyl sulfoxide followed by the addition of 1-fluoro-4-nitrobenzene in 43 wt% yield. Its inherent viscosity was 0.606 g/cm${\cdot}$sec determined from a solution of 0.125 g of the above polymer dissolved in 25 ml of 98% sulfuric acid at $30^{\circ}C.$ In order to synthesize poly(m-phenylene isophthalamide), 1,3-phenylenediamine is allowed to react with isophthaloyl chloride in chloroform in the presence of triethylamine and added triethylamine hydrochloride. The value of inherent viscosity is 0.560 g/cm${\cdot}$sec measured at the same condition. The substitution ratio of N-p-nitrophenyl poly(m-phenylene isophthalamide) was to be 16.7∼47.0% by using the $^1H-NMR$ integration. When the higher inherent viscosity of poly(m-phenylene isophthalamide) was used, lower substitution ratio would be calculated.

• Journal of Adhesion and Interface
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• v.13 no.3
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• pp.109-115
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• 2012

Monodisperse blue-colored poly(styrene-co-acrylic acid) latices were successfully prepared by seeded emulsion polymerization. Blue-colored latices with carboxyl anionic charge on the surface were synthesized at the second stage with the introduction of Blue 606 dye, acrylic acid, and 0.21 ${\mu}m$-polystyrene seed. All the blue-colored latices synthesized in this study were in the size range of 0.25~0.42 ${\mu}m$ and all uniform with less than 1.01 in PSD. The particle size increased with the addition of acrylic acid being delayed and colloidally stable latices were obtained over 30 min after its addition. The blue-colored latex with 20 wt% acrylic acid showed -145 mV of zeta-potential and $-9.4{\times}10^{-6}\;cm^2/Vs$ of electrophoretic mobility, and with 25 wt% of DVB showed high $T_g$ at 396.7 K.

• Korean Journal of Materials Research
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• v.16 no.10
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• pp.606-613
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• 2006

This study was purposed to evaluate the influence of anodically oxidized film on titanium (Ti) onto MG-63 osteoblast-like cell attachment and activity. Only scratch lines created by polishing were seen in ASR and ANO-1 groups. About $1.5{\mu}m$-thick homogeneous oxide film which has pores of about $0.5{\mu}m$ diameter were formed in ANO-12. The crystalline structure of the oxide films formed by anodization in phosphoric acid electrolyte was $TiP_2O_7$. The total protein amounts of ANO-1 and ANO-12 groups showed higher values of maximum protein amount than that of AS-R group. At 3 days of incubation, total protein amount showed higher value in ANO-2 when comparing to that of AS-R (p<0.05). Based on the results of ALPase activity test, the degree of MG-63 cell differentiation for initial mineralization matrix formation was similar. For all the test groups after 1 day of incubation, MG-63 cells grew healthily in mono-layer with dendritic extensions. After incubation for 3 days, the specimen surfaces were covered more densely by cells, and numerous micro filaments were extruding to the extracellular matrix.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.606-616
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• 2022

This study explored the degree of change in children perceived by single parents and examined the effect of single parents' spending family time and participation of leisure activities on their school-aged children. Hierarchical multiple regression was utilized to analyze data of 1,162 people who responded to the single parent survey collected by the Korea Women's Policy Research Institute in 2018. Results showed that single parents' spending family time and participation of leisure activities influenced positive change on their school-aged children. Implications and suggestions to support single parents' parenting environment are discussed.