• Journal of Korean Society for Atmospheric Environment
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• v.4 no.1
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• pp.13-22
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• 1988

Interactions between hydrodesulfurization of thiophene and hydrodenitrogenation of pyridine and the kinetic analysis were studied over $Ni-W/\gamma-Al_2O_3$ catalysts and this study was made at temperatures ranging from 473-673 K and at total pressures ranging from 10-25 $\times 10^5$ Pa. Hydrodesulfurization of thiophene was inhibited by presence of pyridine at all temperatures studied, and the rate of pyridine hydrodenitrogenation was slower than that of thiophene hydrodesulfurization in the operating conditions. Pyridine hydrodenitrogenation was also inhibited by the presence of thiophene at low temperatures but was enhanced by the thiophene at temperatures higher than 613K. Thiophene reaction rate was determined by multiple linear regression analysis using Langmuir-Hinshelwood-Hougen-Watson model and the result was given to be $r = kP_T^p_H/(1+K_Tp_T+K_Pp_P)^2$. At each temperature, reaction rate constants and absorption equilibrium equilibrium constants were determined and the activation energy was 12.98 kcal/gmol from Arrhenius plot.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.81-84
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• 2003

The effect of annealing condition on the texture and microstructure development in Ni tapes fabricated by cold-rolling including powder metallurgy was investigated. The Pole-figure results showed that the Ni tapes annealed at lower temperature than 50$0^{\circ}C$ were the mixture of brass deformation texture and cube texture. The specimens annealed at high temperatures had only well-developed cube texture and the FWHMs of in-plane and out-of-plane were in the range of 8-10$^{\circ}$. The degree of texture was not significantly depended on annealing temperatures. The grain morphologies of Ni tapes prepared at low temperatures showed serrated grain boundaries due to incomplete recrystallization, but the specimens prepared at high temperatures showed stabilized grain shape without serrated grain boundaries.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.8 no.1
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• pp.27-31
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• 2002

In this study, the physical properties of starch adhesive by temperature in carrier and main part for the Stain-Hall method were analyzed. The temperatures of starch solutions in carrier part were inversely proportional to the viscosities. The viscosities of starch solutions were maintained similarly if 2nd temperatures were same independent on the those of the 1st temperatures in carrier part. the starch solutions showed similar viscosities in all range except the viscosity of the solutions in $30^{\circ}C\;and\;40^{\circ}C$. The viscosities of starch adhesives in main part were in proportion to those of starch solutions in carrier part. The viscosities of starch adhesives in main part were maintained similarly if 2nd temperatures in carrier part were same. The viscosities of starch adhesives in main part were low when the ultimate temperature of starch solutions in carrier part were high.

• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.863-870
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• 2024

Meju, a fermented soybean brick, is a key component in soybean foods like doenjang and ganjang, harboring a variety of microorganisms, including bacteria and fungi. These microorganisms significantly contribute to the nutritional and sensory characteristics of doenjang and ganjang. Amplicon-based next-generation sequencing was applied to investigate how the microbial communities of meju fermented at low and high temperatures differ and how this variation affects the microbial communities of doenjang, a subsequently fermented soybean food. Our metagenomic data showed distinct patterns depending on the fermentation temperature. The microbial abundance in the bacterial community was increased under both temperatures during the fermentation of meju and doenjang. Weissella was the most abundant genus before the fermentation of meju, however, it was replaced by Bacillus at high temperature-fermented meju and lactic acid bacteria such as Weissella and Latilactobacillus at low temperature-fermented meju. Leuconostoc, Logiolactobacillus, and Tetragenococcus gradually took over the dominant role during the fermentation process of doenjang, replacing the previous dominant microorganisms. Mucor was dominant in the fungal community before and after meju fermentation, whereas Debaryomyces was dominant under both temperatures during doenjang fermentation. The dominant fungal genus of doenjang was not affected regardless of the fermentation temperature of meju. Strong correlations were shown for specific bacteria and fungi linked to specific fermentation temperatures. This study helps our understanding of meju fermentation process at different fermentation temperatures and highlights different bacteria and fungi associated with specific fermentation periods which may influence the nutritional and organoleptic properties of the final fermented soybean foods doenjang.

• Korean Journal of Remote Sensing
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• v.10 no.2
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• pp.83-107
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• 1994

Sea surface temperatures (SSTs) estimated by using the operational SST derivation equations of NOAA/NESDIS were compared with satellite-tracked drifter temperatures. As a result of eliminating cloud-filled or contaminated pixels through several cloud tests, 69 matchup points between the drifter temperatures and the SSTs estimated with NOAA satellite 9, 10. 11 and 12 data from August, 1993 to July, 1994 were collected. Multi-channel sea surface temperature(MCSST) using a split window technique showed an approximately $1.0{\circ}C$ rms error as compared with the drifting buoy temperatures for 69 coincidences. Accuracies for satellete-derived sea surface temperatures were evaluated for only NOAA-11 AVHRR data which had relatively large matchups of 35points as compared with other satellites. For the comparison of the oberved temperatures with the calculated SSTs, linear MCSST and nonlinear cross product sea surface temperature(CPSST) algorithms by the split, the dual and the triple window technique were used respectively. As a result, the split window CPSSTs showed the smallest rms error of $0.72{\circ}C$. Defferences between the split window SSTs and the drifter temperatures appeared th have a linear tendency against the drifter temperatures and also against the differences between AVHRR channel 4 and 5 brighness temperatures. This indicates some possibilities that satelite-derived SSTs operationally calculated from the NOAA/NESDIS equation in the seas around Korea have been underestimated as compared with actural SSTs in case sea water temperature is relatively low or the atmosphere over the sea surface is very dry like in winter, while overstimated in case of high temperature or very moist atmospheric equations based on local sea measurements around Korea instead of global measurements should be derived.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.292-297
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• 2013

Winter turfgrass injury is one of the critical problems of many golf courses in Korea. Turfgrass loss from freezing injury due to low temperature leads to many types of damages including weed invasion, increased herbicide cost, increased soil erosion, and expensive re-establishment. Although Kentucky bluegrass (Poa pratensis L.) which is the most widely used among cool-season grasses in Korea is well known as cold tolerance species, freezing injuries to Kentucky bluegrass during winter are often found. Protecting the turfgrass crown is necessary to recover from low temperature stress in winter because shoots and roots can be recovered from the crown. Turf covers may protect the crowns from direct low temperatures and desiccation. Six different turf covers were installed to cover Kentucky bluegrass during a period of low temperatures. Turf covers had positive effects for spring green-up of Kentucky bluegrass based on the study. Applying any type of turf covers on Kentucky bluegrass resulted in an increase average and minimum temperature compared to the uncovered plot. Among turf covers, clear PVC film without holes produced the longest root length and the highest turfgrass quality.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.3
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• pp.328-333
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• 2019

During the winter of 2017/2018, significantly low water temperatures were detected around the western and southern coasts of Korea (WSCK). In this period, sea surface temperature (SST) in the Korea Waters was about $2^{\circ}C$ lower than mean temperature. Using the real-time observation system, we analyzed the temporal variation of SST during this period around the western and southern coasts. Low water temperature usually manifested over a period of about 10 ~ 20 days. The daily Arctic oscillation index was also similarly detectable with the variation of SST. From the cross-correlation function, we compared two periodic variations, which were SST around the WSCK and the Arctic oscillation index. The cross correlation coefficients between both variations were approximately 0.3 ~ 0.4. The time lag of the two time series was about 6 to 7 days. Therefore, significantly low water temperatures during winter in the Korean coastal areas usually became detectable 6 to 7 days after the negative peak of Arctic oscillation.

• 한국전기화학회:학술대회논문집
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• 1998.10a
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• pp.90-90
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• 1998

• Magazine of the Korea Concrete Institute
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• v.9 no.4
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• pp.31-41
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• 1997

• Proceedings of the Materials Research Society of Korea Conference
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• 1993.11a
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• pp.11-11
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• 1993