• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.12
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• pp.965-971
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• 2001

$\beta$-Ga$_2$O$_3$ nanobelts and nanoparticles were synthesized from mechanically ground GaN powders with thermal annealing in a nitrogen atmosphere and an oxygen atmosphere, respectively. The study of field emission scanning electron microscopy (FESEM) on the microstructures of nanomaterials revealed that the nanobelts synthesized in the nitrogen atmosphere are with the range of 20~1000nm width and 10 ~100nm thickness, and that nanomaterials are nanoparticles with 20~50nm radius obtained by thermal annealing in an oxygen atmosphere. The crystal structure of the $\beta$-Ga$_2$O$_3$ nanobelts and nanoparticles was in this study investigated by X-ray diffractometer (XRD) and high-resolution transmission electron microscope (HRTEM). The formation processes of the nanobelts and nanoparticles will be discussed in this paper.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.343-344
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• 1996

Solar IR spectra have been utilised by us to derive log gf values for atomic lines due to 17 chemical elements. in the J and H bands, i.e. in the wavelength ranges 1.00 - 1.34 ${\mu}m$ and 1.49 - 1.80 ${\mu}m$ respectively. The observed central line depths were based on the FTS atlases published at. Liege and KPNO. We also reprot new log gf values for 51 lines for which neither theoretical nor experimental values are available till date.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.61-65
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• 2013

Modified atmosphere (MA) of reduced $O_2$ and elevated $CO_2$ concentrations has been used for keeping the quality of fresh produce and extending the shelf life. As a way to attain the beneficial MA package around the produce, a gas diffusion tube or perforation can be attached onto the container and controlled on real time in its opening/closing responding to $O_2$ and $CO_2$ concentrations measured by gas sensors. The timely-controlled opening of the gas diffusion tube can work in harmony with the produce respiration and help to create the desired MA. By use of the mathematical modeling, the effect of tube dimension on the controlled container atmosphere was figured out in this study. Spinach and king oyster mushroom were used as typical commodities for designing the model container system (0.35 and 0.9 kg in 13 L, respectively) because of their respiration characteristics and the optimal MA condition ($O_2$ 7~10%/$CO_2$ 5~10% for spinach; $O_2$ 2~5%/$CO_2$ 10~15% for mushroom). With a control logic for the gas composition to stay as close as possible to optimum MA window without invading injurious low $O_2$ and/or high $CO_2$ concentrations, the atmosphere of the sensor-controlled container could stay at its lower $O_2$ boundary or upper $CO_2$ limit under certain tube dimensional conditions. There were found to be the ranges of the tube diameter and length allowing the beneficial MA. The desired range of the tube dimension for spinach consisted of combinations of larger diameter and shorter length in the window of 0.3~2 cm diameter and 0.2~10 cm length. Similarly, that for king oyster mushroom was combinations of larger diameter and shorter length in the window of 0.9~2 cm diameter and 0.2~3 cm in length. Clear picture on generally affordable tube dimension range may be formulated by further study on a wide variety of commodity and pack conditions.

• Journal of Environmental Science International
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• v.20 no.8
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• pp.963-975
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• 2011

For this research, they were monitored $CO_2$ flux and environmental factors ($CO_2$ concentration, soil temperature, soil moisture, soil organic carbon, soil pH, soil Eh) in foreshore, paddy field and woods sites at the winter season (January 2009) and the summer season (September 2009). Seasonal and spatial variations for monitored data were analyzed, and linear regression functions of $CO_2$ flux as environmental factors were estimated. $CO_2$ fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the winter season were shown $-8\;mgCO_2m^{-2}hr^{-1}$ and $-25\;mgCO_2m^{-2}hr^{-1}$, respectively. $CO_2$ fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the summer season were shown $47\;mgCO_2m^{-2}hr^{-1}$ and $117\;mgCO_2m^{-2}hr^{-1}$, respectively. Thus, $CO_2$ was sunk from atmosphere to surface at the winter season and it was emitted from surface to atmosphere at the summer season. $CO_2$ fluxes in woods site were emitted $145\;mgCO_2m^{-2}hr^{-1}$ at the winter season and $279\;mgCO_2m^{-2}hr^{-1}$ at the summer season.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1147-1159
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• 2015

The purpose of this study was to verify the analysis of level of importance and satisfaction in recognitions of elementary school students on useful classes among school sport clubs using Importance-Performance analysis. In order to achieve this objective, samples were taken by using convenience sampling method among non-probability sampling methods, and 384 data were used as the final valid samples for this study except 16 data with missing items or insincere responses. The results of frequency analysis, exploratory factor analysis, independent samples t-test, IPA analysis by using SPSS 20.0 were as follows. First, Iquadrant included education contents of enhance ability to ingenuity, teaching method of provides option, teaching method of encourage participation activity, education contents of the aspect of fun, evaluation of motor function and emotion, education contents of explains key contents easily, and education contents of understanding overall context. II quadrant included education environment of good sport facility, class environment of fair opportunity for activity, class atmosphere of arouses interest, and class atmosphere of autonomous and voluntary. III quadrant included diverse teaching method and instructor's demonstration, class atmosphere of systematic learning, evaluation of fairness, objectivity, and credibility, and an atmosphere that can exercise. IV quadrant included education contents of enable acquisition of knowledge and degree of improvement into consideration, and class atmosphere of trust and respect between instructor and student.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.3
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• pp.217-221
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• 2022

Container system automatically controlled in its atmosphere of high CO₂/low O₂ was devised to contain and store pork belly meat at chilled temperature. The meat in the container system was compared in the quality preservation at 0℃ for 21 days to that in air-filled container and vacuum package. The container atmosphere could be controlled to be of 47~60% CO₂ and 7~10% O₂ through time-controlled intermittent CO₂ injection. The controlled atmosphere in the developed system was effective in suppressing pH change and aerobic bacterial growth contributing to sensory quality preservation. Compared to control of air-filled container, vacuum packaging showed lower microbial growth and slower pH change on the meat but with high drip loss. The devised container system to keep high CO₂ and mildly low O₂ concentrations is effective in the meat quality preservation on overall, and may be extended to a variety of meat products with possible modification tuned for product requirements.

• Fashion & Textile Research Journal
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• v.24 no.4
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• pp.372-385
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• 2022

In this study, the patterns expressed on nineteenth-century blue and white porcelain among Joseon white porcelain were selected as the material for the development of the car seat fabric design. It was intended to be applied to car seat design by incorporating Korea's own traditional patterns to fit modern sensibility. First, seven pieces of nineteenth-century blue and white porcelain were selected through the literature, and motifs were produced using adobe illustrator, a computer graphic program. Seven car seat fabric designs were developed according to the construction method and development method of the produced motif. Work 1 was designed to elicit a soft and feminine atmosphere using the peony pattern shown in Table 1-1. Work 2 aimed to express a luxurious atmosphere using the image of the mountain expressed in Table 1-2 as a design material. Works 3 was designed by freely arranging the letters of luck expressed in Table 1-3 to form a free and dynamic image. Work 4 was intended to express a stable and rhythmic atmosphere by horizontally arranging the images of the gently curved wings, tail, and rhythmical tail feathers of the phoenix expressed in Table 1-4. Work 5 was designed in a vertical arrangement using the patterns and silhouettes of the tiger's back expressed in Table 1-5. Work 6 was designed using the wave pattern expressed in Table 1-6 to replicate the rhythmic atmosphere. Work 7 was designed using the images of rocks, waves, and the sun in Table 1-7 to express a calm and antique atmosphere.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2529-2530
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• 2011

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.363-364
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• 2008

• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.302-302
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• 2005