• Korean Journal of Microbiology
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• v.52 no.1
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• pp.98-109
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• 2016

The study was aimed to investigate the mixing ratio of kiwi and persimmon juices for the production of good quality wine by Saccharomyces cerevisiae Y28. Firstly, the optimum condition of rapidase treatment for the kiwi and persimmon juices was established, thereafter various mixing ratio (10:0, 9:1, 8:2, 7:3, 6:4, 5:5) of kiwi and persimmon was investigated regarding physiochemical properties and flavor compounds of wine. As the result, the optimum conditions were obtained as 0.3% rapidase for 1 h in kiwi and 0.3% rapidase for 3 h in persimmon. According to higher ration of persimmon, the pH of wines increased from 3.69 to 3.77, while the acidity of wines decreased from 2.07% to 1.51% at 14 days fermentation. The ranges of brix and reducing sugar in wines were decreased which ranges around 9.6 to 8.8 and 6.07 to 6.90 g/L, respectively, after fermentation. Major organic acid in wines were identified as tartaric acid, malic acid, and citric acid. A small amount of free sugar such as sucrose and glucose were detected in wines, but fructose was completely absent. The soluble phenolic contents were decreased that ranges around 1.00 to 1.25 g/L, in contrast, browning degree were increased ranges around 0.212 to 0.412 after fermentation. The major flavor components were identified as ethyl acetate and hydrazine, and 1,1-dimethyl. Importantly, phenylethyl alcohol was detected from the all wines that have a typical rose like flavor. But sensory test results and preference of kiwi-persimmon (7:3) mixing wine was better than the other wines.

• Food Science of Animal Resources
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• v.26 no.3
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• pp.269-275
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• 2006

The objective of this study was to investigate the physicochemical, microbiological and sensory properties of food additive-free grilled pork products manufactured using loin (T1), tender loin (T2) and ham (T3). The samples were heated for 30 min at $60^{\circ}C$, and then 50 min for $150^{\circ}C$. After cooling, vacuum packaged grilled pork samples was stored at $4{\pm}1^{\circ}C$ for 40 days. The pH values of grilled pork samples ranged from 5.92 (T1) to 6.10 (T3) at the initial storage time, and from 6.28 (T1) to 6.60 (T3) after 40 days. The water holding capacities(%) was $85.99{\sim}93.24%$ for T1, $95.26{\sim}93.89%$ for T2 and $89.11{\sim}94.67%$ for T3, all of which were slightly higher than those of other pork products. The shear force values of T2 were significantly higher(p<0.05) than those of the other pork products throughout the storage period. The TBARS and VBN values of T2 were significantly higher(p<0.05) than those of T1 and T3. With regard to microorganisms, all grilled pork samples was in good condition, showing $1.93{\sim}3.48\;log_{10}$ CFU/g via total plate counts, and $1.74{\sim}3.48\;log_{10}$ CFU/g far lactic acid bacteria throughout the storage period. Regarding sensory evaluation, the scores of overall acceptability in all products were above 5.0 points through 40 days of storage.

• Food Science of Animal Resources
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• v.32 no.1
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• pp.68-76
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• 2012

Olive oil and grape seed oil (10% of meat weight) were added to a package of beef loin. The package was then vacuum-sealed, and high pressure was applied (HP, 600 MPa) to investigate the effect of the penetration of vegetable oil into meat and safety and quality of the meat. Non-HP (0.1 MPa) without any oil treatment was considered as a control. The color $L^*$ and $b^*$-values of beef loin were higher and the $a^*$-value was lower than those of the control after HP at 600 MPa. The total aerobic bacterial number was 3 Log CFU/g in the control but no viable cell was detected in the beef with 600 MPa. All inoculated E. coli and L. monocytogenes were inactivated by HP. The beef loin with vegetable oil added without HP did not show any difference in fatty acid composition, but that treated by HP showed a higher oleic and linoleic acid content when olive oil and grape seed oil were added, respectively. The addition of olive oil inhibited lipid oxidation, and sensory evaluation revealed that there was no difference among treatments. The results indicate that the addition of vegetable oil followed by the application of HP enhances the safety of beef loin, changing the fatty acid composition in a health beneficial way. In addition, the use of olive oil can inhibit lipid oxidation induced by HP.

• Land and Housing Review
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• v.9 no.3
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• pp.1-8
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• 2018

In Europe and the United States, the use of limit states design has almost been established for pile foundation design. According to the global trend, the Ministry of Land, Transport and Maritime Affairs has established the basic design criteria of the bridge under the limit state design method. However, it is difficult to reflect on the design right now because of lack of research on resistance coefficient of the pile method and ground condition. In this study, to obtain the resistance coefficient of PHC bored pile which is widely used in Korea, the bearing capacity calculated by the LH design standard and the bridge design standard method, the static load test(21 times) and the dynamic load test(EOID 21 times, Restrike 21) The reliability analysis was performed on the results. The analysis of the resistance coefficient of PHC bored pile by loading test was analyzed by adding more than two times data. As a result, the resistance coefficient obtained from the static load test(ultimate bearing capacity) was 0.64 ~ 0.83 according to the design formula and the target reliability index, and the resistance coefficient obtained from the dynamic load test(ultimate bearing capacity) was 0.42~0.55. Respectively. The resistance coefficient obtained from the modified bearing capacity of dynamic load test(EOID's ultimate end bearing capacity + restrike's ultimate skin bearing capacity) was 0.55~0.71, which was reduced to about 14% when compared with the resistance coefficient obtained by the static load test(ultimate bearing capacity). As a result of the addition of the data, the resistivity coefficient was not changed significantly, even if the data were increased more than 2 times by the same value or 0.04 as the previous resistance coefficient. In conclusion, the overall resistance coefficient calculated by the static load test and dynamic load tests in this study is larger than the resistance coefficient of 0.3 suggested by the bridge design standard(2015).

• Journal of Korea Water Resources Association
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• v.53 no.6
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• pp.427-436
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• 2020

It is uncertain how global climate change will influence future drought characteristics over the Korean peninsula. This study aims to project the future droughts using climate change and land use change scenarios over the Korean peninsula with the land surface modeling system, i.e., Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro). The Representative Concentration Pathways (RCPs) 2.6 and 8.5 are used as future climate scenarios and the Shared Socio-economic Pathways (SSPs), specifically SSP2, is adopted for the land use scenario. The using Threshold Level Method (TLM), we identify future hydrological and ecological drought events with runoff and Net Primary Productivity (NPP), respectively, and assess drought characteristics of durations and intensities in different scenarios. Results show that the duration of drought is longer over RCP2.6-SSP2 for near future (2031-2050) and RCP8.5-SSP2 (2080-2099) for the far future for hydrological drought. On the other hand, RCP2.6-SSP2 for the far future and RCP8.5-SSP2 for the near future show longer duration for ecological drought. In addition, the drought intensities in both hydrological and ecological drought show different characteristics with the drought duration. The intensity of the hydrological droughts was greatly affected by threshold level methods and RCP2.6-SSP2 for far future shows the severest intensity. However, for ecological drought, the difference of the intensity among the threshold level is not significant and RCP2.6-SSP2 for near future and RCP2.6-SSP2 for near future show the severest intensity. This study suggests a possible future drought characteristics is in the Korea peninsula using combined climate and land use changes, which will help the community to understand and manage the future drought risks.

• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.276-283
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• 1997

This experiment was conducted to investigate the optimum temperature and the effects of sulfuric acid, flowing water and $GA_3$ on the germination of Bupleurum falcatum. At the same time, the effect of germination-related compounds in Bupleurum falcatum seed was tested. Among the tested temperatures $(15,\;20,\;25\;and\;30^{\circ}C)$ the highest germination rate was obtained at $15^{\circ}C$. The optimum soaking time of sulfuric acid was 5 minutes at the concentration of both 0.1 and 1.0%. At the same time, the germination rate was highest when Bupleurum falcatum seed was washed for 2 days in the flowing water before germination test. The effect of $GA_3$ on the germination was highest at 100 ppm out of 10, 50 and 100 ppm. Regardless of treatments, the germination rate of Jeongseon species was higher than that of Mishima species. SEM photographs revealed that most of germination-inhibiting substances in the seed coat were washed away by rinsing in the flowing water for 2 days thus the seed coat became more smooth. The 4, 000 ppm alcohol extract of Bupleurum falcatum seeds inhibited the germination of lettuce seeds as much as 41.7% in Jeongseon species and 58.3% in Mishima species. The higher extract concentration from seed of Bupleurum falcatum, the lower the germination of lettuce seeds was obtained. Out of phenolic acids, the contents of orchinol, pyrogallol, and p-hydroxybenzoic acid were highest in both varieties. Compared with Mishima species, Jeongseon species showed much higher content of salicylic and vanillic acid.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.67-73
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• 2005

Photoautotrophic bacteria are promising candidates for the production of poly(3-hydroxybutyrate) (PHB) since they can address the critical problem of substrate costs. In this study, we isolated 25 Tn5-inserted mutants of the Synechocystis sp. PCC 6803 which showed enhanced PHB accumulation compared to the wild-type strain. After 5-days cultivation under nitrogen-limited mixotrophic conditions, the intracellular levels of PHB content in these mutants reached up to $10-30\%$ of dry cell weight (DCW) comparable to $4\%$ of DCW in the wild-type strain. Using the method of inverse PCR, the affected genes of the mutants were mapped on the completely known genome sequence of Synechocystis sp. PCC 6803. As a result, the increased PHB accumulation in 5 mutants were found to be resulted from defects of genes coding for NADH-ubiquinone oxidoreductase, O-succinylbenzoic-CoA ligase, photosystem II PsbT protein or histidine kinase, which are involved in photosystem in thylakoid inner membrane of the cell. The values of $NAD(P)H/NAD(P)^+$ ratio in the cells of these mutants were much higher than that of the wild-type strain as measured by using pulse-amplitude modulated fluorometer, suggesting that PHB synthesis could be enhanced by increasing the level of cellular NAD(P)H which is a limiting substrate for NADPH-dependent acetoacetyl-CoA reductase. From these results, it is likely that NAD(P)H would be a limiting factor for PHB synthesis in Synechocystis sp. PCC 6803.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.4
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• pp.271-278
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• 2004

This paper shows our experiment is performed to understand the exposure tendency of $^{137}Cs$ according to the height of area and also, to supplement it by considering chemical characters of $^{137}Cs$ exposed to the soil. The samples we use for this experiment are from the general flat area of Yeonggwang county where it has NPPs, the high places of Keumjung & Bulgap mountains, and Naejan mountain where it is quite far from the NPPs. The data from this experiment show that the exposure of $^{137}Cs$ is not harmful since its range is around 252 Bq/kg-dry in most of sampled soils such as from the general flat area, the high place of Keumjung mountain where is 2 km away from the NPPs, the other high place of Bulgap mountain where is about 20 km away from the NPPs, and Naejan mountain where it is far from the NPPs. Not like the general flat area, however, the data show that the higher the area is the more $^{137}Cs$ is exposed. That is, at the top of mountains, the more $^{137}Cs$ is exposed compared to at the bottom area. It is almost $2{\~}6$ times more than the general flat area of Yeonggwang county where it has NPPs. The data also show that the spread of $^{137}Cs$ is deeply related to the geographical(the height of area, rainfall, etc..) factors and chemical factors of soils. As the geographical factors, there are far more chances to be exposed of $^{137}Cs$ at the high area of mountains through the air compared to at lower area and therefore, we can get more high-leveled readings of $^{137}Cs$ at the high area while it is low-leveled ones at the general flat area even if both of them have the same soil conditions. Regarding the chemical factors of soil, it is clarified that the CEC is the key factor. The CEC means the capability of sticking $^{137}Cs$ accumulated into the soil. Hence, the more CEC it has the more high-leveled readings of $^{137}Cs$ we get under the same geographical condition.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.161-169
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• 2012

The RCP 8.5 scenario based temperature outlook (12.5 km resolution) was combined with high-definition gridded temperature maps (30 m grid spacing) across the Korean Peninsula in order to reclassify the cold hardiness zone for winter barley, a promising grain crop in the future under warmer winter conditions. Reference maps for the January minimum and mean temperature were prepared by applying the watershed-specific geospatial climate prediction schemes to the synoptic observations from 1981 to 2010 across North and South Korea. Decadal changes in the January minimum and mean temperatures projected by a regional version of RCP8.5 climate change scenario were prepared for the 2011-2100 period at 12.5 km grid spacing and were subsequently added to the reference maps, producing the 30 m resolution temperature surfaces for 9 decades from 2011 to 2100. A criterion for threshold temperature to grow winter barley safely in Korea was applied to the future temperature surfaces and the resulting maps were used to predict the production potential of 3 cultivar groups for the 9 future decades under the projected temperature conditions. By 2020s, hulled barley cultivars could be grown safely at the southern part of North Korea as well as the mountainous Gangwon province. Furthermore, most of South Korean rice paddies will be safe for growing naked barley after harvesting rice. Also, dual cropping systems such as 'winter-barley after rice' could be possible at most of the North Korean rice paddies by 2040s. Additional grain production in North Korea could increase up to 4 million tons per year if dual cropping systems can be fully operated, i.e., winter barley after rice at all lowlands and winter barley after maize or potato at all uplands.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.151-161
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• 2004

Three dimensional quantitative structure-activity relationships (3D-QSAR) studies for the protox inhibition activities against root and shoot of rice plant (Orysa sativa L.) and barnyardgrass (Echinochloa crus-galli) by a series of new A=3,4,5,6-tetrahydrophthalimino, B=3-chloro-4,5,6,7-tetrahydro-2H-indazolyl and C=3,4-dimethylmaleimino group, and R-group substituted on the phenyl ring in 1-(5-methyl-3-phenylisoxazolin-5-yl)methoxy-2chloro-4-fluorobenzene derivatives were performed using comparative molecular field analyses (CoMFA) methodology with Gasteiger-Huckel charge. Four CoMFA models for the protox inhibition activities against root and shoot of the two plants were generated using 46 molecules as training set and the predictive ability of the each models was evaluated against a test set of 8 molecules. And the statistical results of these models with combination (SIH) of standard field, indicator field and H-bond field showed the best predictability of the protox inhibition activities based on the cross-validated value $r^2_{cv.}$ $(q^2=0.635\sim0.924)$, conventional coefficient $(r^2_{ncv.}=0.928\sim0.977)$ and PRESS value $(0.091\sim0.156)$, respectively. The activities exhibited a strong correlation with steric $(74.3\sim87.4%)$, electrostatic $(10.10\sim18.5%)$ and hydrophobic $(1.10\sim8.30%)$ factors of the molecules. The steric feature of molecule may be an important factor for the activities. We founded that an novel selective and higher protox inhibitors between the two plants may be designed by modification of X-subsitutents for barnyardgrass based upon the results obtained from CoMFA analyses.