• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.330-339
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• 2009

The material properties of Cedar (Cryptomeria japonica) were evaluated according to heat treatment conditions. The special focus was made on the color control of cedar wood by heat treatment. The difference of color between sapwood and heartwood could be reduced by heat treatment at a temperature above $170^{\circ}C$. Long heating time was more effective in reducing the difference. The Equilibrium Moisture Content (EMC) of heat-treated wood was as low as 50 percent. The result obviously indicates that heat-treated wood is more dimensionally stable in the change of moisture condition than the control. The heat-treated wood was also effective in increasing the durability against wood rotting fungi. However, more study is required to develop heat treatment as an environmentally-friendly technology for wood preservation without chemical. The mechanical properties of heat-treated wood showed relatively higher performance than the control in general. Meanwhile the dramatic decrease in impact bending stress due to the loss of ductility may limit uses of heat-treated wood in certain cases. There were no significant changes in microscopic structure which may cause changes in mechanical properties. Further study on the chemical analysis of heat-treated wood is needed to scrutinize the causes of changes of material properties.

• Korean Journal of Microbiology
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• v.52 no.1
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• pp.84-97
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• 2016

Isolates from Korean fermented soybean paste were identified as Enterococcus faecium SBP12, Pediococcus halophilus SBP20, Lactobacillus fermentum SBP33, Leuconostoc mesenteroides SBP37, Pediococcus pentosaceus SBP41, Lactobacillus brevis SBP49, Lactobacillus acidophilus SBP55, and Enterococcus faecalis SBP58 according to conventional morphological and biochemical characteristics, carbohydrate fermentation profiling, and 16S rRNA sequence comparison. Strain SBP20, SBP33, SBP49, and SBP55 showed very resistance to simulated gastric and intestinal juices with final populations exceeding 6 log CFU/ml, whereas cells of SBP12 and SBP58 after exposure to low pH were dramatically decreased within 2 h. Among 4 strains having good tolerance to gastrointestinal conditions, the high adhesive ability to HT-29 cells, antibiotic resistance, and antimicrobial activity against food-borne pathogens Bacillus cereus ATCC 11778 and Staphylococcus aureus ATCC 6538 were observed with SBP49 and SBP55, therefore, these two strains were confirmed as putative probiotic candidates. There was no significant difference between the sourdoughs fermented with SBP49 and SBP55 with respect to the values of pH, total titratable acidity, and viable cell count. During sourdough fermentation, SBP49 strain produced significantly greater amounts of lactic acid than SBP55 strain, which secreted large quantities of hydrogen peroxide. SBP49 and SBP55 strains producing the antimicrobial substances such as lactic acid, hydrogen peroxide, and bacteriocin effectively inhibited B. cereus and S. aureus inoculated in the sourdough.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.849-854
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• 2006

The objective of this study was to evaluate the quality characteristics of Dotoridasik prepared by the addition of acorn powder (0%, 20%, 40%, 60%, 80%). The Proximate components were 85.89% carbohydrate, 1.38% crude fat, 0.84% crude protein and 0.32% crude ash. The moisture content of Dotoridasik showed no significant difference between the added acorn powder and control groups. The following Hunter color values are not part of the sensory evaluation testing in the results of for Dotoridasik, decreased while the a and b values increased with increasing acorn powder addition. The bitter taste was evaluated as being improved with increasing acorn powder addition. Dotoridasik with 40% acorn powder showed the highest acceptance. In the mechanical evaluation, hardness recording which from control Will increase with acorn powder it shows a high shame(p<0.05), the adhesiveness result springiness it was not visible a consider difference especially also utterly unintelligible).

• Korean journal of food and cookery science
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• v.17 no.5
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• pp.464-471
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• 2001

Physicochemical and sensory properties of Kakdugi prepared with spring cultivars of radish were compared during fermentation. Among 5 cultivars,` ‘Bagkwang’‘Chunhadaehyung’and ‘Bakbong’ were heavier in average weight and longer in length than others. Sugar content and hardness were the highest in ‘91144’and ‘Bakbong’, while moisture content, in ‘Bagkwang’ and ‘Bakbong’, During fermentation at 20$\^{C}$ for 11 days, a great decrease in pH and great increase of acidity were observed in five Kakdugi samples after day 2. The acidity of ‘Bagkwang’ and ‘Housebommoo’ increased rapidly after day 2 until day 5 and then reached around 1.04-1.08% (lactic acid) at day 11, while those of ‘91144’ and ‘Bakbong’ increased slowly until day 5, but after day 7 increased rapidly up to 1.2-1.3%(lactic acid). ‘91144’ showed the highest ‘a’ value(redness), but ‘Bagkwang’, the lowest. Decrease in hardness during fermentation was the least in ‘Bakbong’, while ‘Chunhadaehyung’, the greatest. The result of sensory evaluation suggested that ‘Bakbong’and ‘Housebommoo’ were the best among spring cultivars of radish for Kakdugi preparation.

• Korean journal of food and cookery science
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• v.26 no.4
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• pp.441-449
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• 2010

The objective of this study was to investigate the physicochemical characteristics of soybeans cultivated in different regions and the accompanying soybean curd properties. To produce soybeans with regional competitiveness and demonstrate the distinctiveness of the soybean product, four regions(Paju, Andong, Muju, Hadong) and four varieties of soybean(Daewonkong, Daepungkong, Seonyukong, Cheogja 2) were selected for these experiments. There was a significant difference in the isoflavone content of soybeans and soybean curds(p<0.05). Soybeans from Andong had the highest content of genistein, daidzein and total isoflavone and soybeans from Hadong had the lowest content of these compound. Fatty acid composition of soybeans demonstrated a significant difference according to region(p<0.05). In particular, soybeans grown under adverse environmental conditions, such as high temperature and low latitude, contained the highest composition of oleic acid and the lowest composition of linoleic acid and linolenic acid. Although fatty acid content of soybean curd had a third of the fatty acid concentration of soybean, the same characteristic was observed in the fatty acid composition of soybean curd. In addition, both soybean and soybean curd had more than 80% unsaturated fatty acids and 50% of the unsaturated fatty acid content was linoleic acid. In conclusion, these results demonstrate the significant difference of soybean and soybean curd originating from different regions and showed the transition of nutritional constituents from soybean to soybean curd as a function of environmental factors. Therefore, we must consider these factors when manufacturing soy products.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.353-357
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• 1995

The purpose of this study was to evaluate the possibility of the laboratory-made rice straw pulp tray(RSPT) for mushroom(Agaricus bisporus) pre-packaging. The quality changes of mushrooms packaged respectively in the RSPT and 'commercial' expanded polystyrene tray(EPST) were observed during storage. The weight losses of mushrooms in the two types of trays were maintained below 5% and the Hunter L values were showed above 76 at $4^{\circ}C$, while mushrooms in RSPTs had better lightness than those in EPSTs during storage at $25^{\circ}C$. There were no significant differences in the hardness values and cap openings between mushrooms in the two types of trays at $4^{\circ}C$. The cap openings of mushrooms were more proceeded in RSPTs than in EPSTs at $25^{\circ}C$ and the weight increases of RSPTs were greater than those of EPSTs during storage at $4^{\circ}C,\;25^{\circ}C$. As a result, it may be favorable to apply the environmentally-friendly RSPT to mushroom pre-packaging under the condition of low storage temperature.

• Journal of Gifted/Talented Education
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• v.26 no.1
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• pp.53-76
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• 2016

This research studies the perception to gifted education teachers between the middle school gifted education for STEAM and Convergence Gifted Education for revitalizing Convergence Gifted Education. The conclusions according to the analysis, it shows that the awareness of gifted education teachers for Convergence Gifted Education is lower than the level of the awareness for STEAM, and it appears that the Gifted education teachers especially has the experience adapting Convergence Gifted Education who awareness for Convergence Gifted Education is the highest. On the other hand, not only teachers has the experience adapting Convergence Gifted Education and the very poorly recognition for the task of Comprehensive Plan for Gifted Education promotion including the development of an creative and convergence content, a they has the very low experience for the development. And it analyzes that although there is no meaningful differences, teachers who are in science gifted teachers and the mature experienced man realizes very optimistically the necessity need of Convergence Gifted Education. Therefore, it analyzes that recognition to the necessity need of Convergence Gifted Education is reinforced through the training for the gifted teachers in the mathematics gifted education and in less teaching experience. But it points out that answers over the majority cognized to resemble the Convergence Gifted Education and STEAM, though the object is only different. Furthermore, it suggests that the differentiated Convergence Gifted Education curriculum providing the suitableness for the characteristic and level is needed for the desirable fixedness.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.728-736
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• 2001

Effects of packaging material and oxygen absorbant on physical and chemical properties of Yukwu were studied during storage to develop packaging conditions. The packaging materials used were PET/EVOH $(16\;{\mu}m)/PL$ : P1 and PET/EVOH $(24\;{\mu}m)/PL$ : P2 with or without oxygen absorbent (E1A : P1 and E2A : P2 for w/ $O_2$, absorbent, E1EA : P1 and E2EA : P2 for w/o $O_2$, absorbent). Color values for Yukwu indicated that L values of E1A, E1EA, E2A and E2EA were decreased during storage while those b values were increased. Hardness and chewiness of Yukwa were generally decreased, however those of E1A and E1EA were rather increased after 6 weeks of storage. Acid value of E2A had maintained less than 2.0 during 12 weeks of storage. E1A, E2A had the below of 20 in peroxide during 12 weeks. Aroma data by using electronic nose showed that there was no difference after 6 week storage time in different packaging materials. Sensory evaluation (Yukwa odor and rancid odor) showed very similar results with electronic nose one. E2A had the highest value of overall acceptability for sensory evaluation. Hardness and cheweness in physical measurement results had the highest correlation with hardness, crispness, overall-acceptability in sensory evaluation results.

• Journal of Korea Water Resources Association
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• v.37 no.9
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• pp.707-718
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• 2004

This study is to analyze the Probable Maximum Flood(PMF) as a part of counterplan for the disaster prevention of hydraulic structures such as dams, according to recent unfavorable weather conditions. During the period of typhoon RUSA in August 2002, the rainfall recorded in Gang-loeng Province was 880mm a day and exceeded the scale of PMP made in 2001. Accordingly, the reconsideration of hydrologic criteria for dam design was inevitable. In the design of dams for flood controls, the design flood must be determined by introducing the concept of maximum values. When the duration of design rainfall is determined, it needs to use the critical duration which causes the maximum flood by the maximum runoff. In this study, we Investigate the variation of critical duration with hydrologic parameters used in three different synthetic unit hydrographs(Clark, Nakayasu and SCS methods). As a result, the total runoff calculated from 24-hour duration is larger than that calculated from the critical duration. We calculate also the hydrographs with three different time distribution models(Huff's 4-quartile, IDF curve and Mononobe) and compare those with measured hydrograph data. From this comparison, we propose that the Huff's 4-quartile model must be used to obtain the desirable data in the hydrologic design of dams.

• Journal of Korea Water Resources Association
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• v.48 no.10
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• pp.857-868
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• 2015

Hydraulic and water quality models with high reliability are necessary for the efficient management of water quality in the reservoir. The model capacity can be demonstrated by the application for the various hydrological conditions. CE-QUAL-W2 model is laterally averaged two-dimensional hydraulic and water quality model. The W2 model, which is suitable for the narrow reservoir like the Jinyang reservoir as compared with the depth and length of waterbody, has been frequently used by many researchers. Namgang watershed is expected to increase the water demand. In this study, the W2 model is validated under two different hydrological conditions; wet year (2011) and normal year (2009). Using hydrological and water quality condition for calibration, 2011, the effect of water intake increase was simulated. The simulation results showed that the increase of water intake led to increase the concentrations in total nitrogen, total phosphorus and Chlorophyll-${\alpha}$ concentration. Especially the concentration increase was appeared during the dry season in each of up to 62.53% (Total nitrogen), 39.07% (Total phosphorus) and 232.19% (Chlorophyll-${\alpha}$). The changes of chlorophyll-${\alpha}$ is similar to those of total phosphorus concentration.