• Journal of Korea Soil Environment Society
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• v.3 no.3
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• pp.3-10
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• 1998

Acid/Base buffer capacity of soil is very important in prediction of contaminant transport for its direct impact on pH change of the system composed of soil-contaminant-water, In this research, diffuse double layer theory as well as two layer electrostatic adsorption model are applied to develop a theoretical model of buffer capacity of soil. Model application procedures are presented as well. Buffer capacity of Georgia kaolinite and Milwhite kaolinite was measured by acid-base titration. Model prediction and experimental results are compared.

• Journal of the Korean Society of Food Culture
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• v.9 no.4
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• pp.329-333
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• 1994

Physicochemical Properties of dough for Jeungpyun(Korean steamed rice cake) were analyzed during fermentation in the ranges of 0 to 10 hours. As fermentation time went by, pH of Jeungpyun dough was decreased while its titratable acidity and lactic acid content were increased continuously. Total sugar content was decreased continuously during fermentation. Reducing sugar content was increased greatly at the early stage of fermentation, reaching maximum value, 101 mg/g-dry matter at 4 hours, but it was decreased thereafter.

• Journal of the Korean GEO-environmental Society
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• v.5 no.4
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• pp.73-79
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• 2004

Mountain side ditch is constructed at the top of cutting slopes around road and it drains the surface water that flowed from upper part. Mountain side ditch is constructed to keep away the influx of the surface water into cutting faces. However, if Mountain side ditch is constructed on the top of cutting slopes, it is cause of trouble. For example, difficulty of quality control and lack of drainage faculty. Therefore, the faculty and establishment propriety of mountain side ditch are evaluated seriously, according to the condition of ground, topography and rainfall in this paper. Results from the study for the numerical analysis of effect of mountain side ditch indicate that safety factor is enlarged about 3% at rainfall.

• Food Science and Preservation
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• v.12 no.5
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• pp.501-506
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• 2005

This study was conducted to investigate the effect of organic acids on solubility of calcium. As a results, acetic and lactic acid showed the most excellent solubility of calcium. Calcium solubility was increased at initial total acid (4%) in citric acid but calcium was insoluble in tartaric acid. After solving, pH and residuals were decreased where as total acidity and calcium content were increased as increment of initial acidity of acetic and lactic acid. Calcium content in seaweed calcium and calcium carbonate were higher than that of nano calcium. Solubility of calcium was more conspicuous at lactic acid than acetic acid.

• Food Science and Preservation
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• v.23 no.7
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• pp.1042-1049
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• 2016

This study was conducted to investigate and compare the characteristics of acetic acid fermentation in detoxified Rhus verniciflua vinegar (DRV) produced by different yeast strains. The DRVs were prepared by static acetic acid fermentation using six different yeast strains (Saccharomyces cerevisiae Fermivin, Pichia kudriavzerii N77-4, Hanseniaspora pountiae HP1-2, Candida tropicalis Y447, Wickerhamomyces anomalus N43-8, and Pichia kluyveri Frootzen). Alcohol content of the S. cerevisiae Fermivin fermented DRV was highest 16.07%. Among the yeast strain DRVs, there were significant differences in alcohol content, but all alcohol levels were 11%. Moreover, there were differences in pH and titratable acidity of the DRVs. The organic acid content of the DRVs ranged from 35.88 to 55.49 mg/mL and there were significant differences among the yeast strain DRVs. Essential free amino acids, particularly glutamic acid, alanine, leucine and valine, were detected in each of the 6 DRVs. Electronic nose analysis revealed that three different volatile chemical patterns were present in the 6 DRVs. The results indicate that yeast strains with different characteristics can produce vinegars with different characteristics.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.192-199
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• 2005

Quality characteristics of curd yoghurt containing loquat extract were evaluated in terms of sensory properties and quality-keeping properties(number of viable cells, pH, titratable acidity). Curd yoghurts were prepared from $10\%(w/v)$ skim milk added with $10\~20\%(v/v)$ loquat extract and fermented by the mixed culture of Streptococcus thermophilus and Lactobacillus acidophilus(1:1) at $37^{\circ}C$ for 12 hours. The results of sensory evaluation of curd yoghurts indicated that flavor, sweet taste, sour taste, aftertaste and overall acceptability of the curd yoghurts with addition of loquat extract showed higher preference than a curd yoghurt with only skim milk. And the curd yoghurt containing $15\%$ loquat extract added $20\~25\%(w/v)$ oligosaccharide had the higher sensory scores in sweet taste, sour taste, aftertaste and overall acceptability among the treatments. When the curd yoghurts added with $15\%$ loquat extract were kept at $4^{\circ}C\;and\;20^{\circ}C$ for 31 days, the number of viable cell counts of the lactic acid bacteria were slightly higher than those in the curd yoghurt with no addition of loquat extract. And also the pH and titratable acidity of all yoghurts were not significantly changed during the storage at $4^{\circ}C$ for 31 days, while the pH and titratable acidity were remarkedly changed during the yoghurts stored at $20^{\circ}C$ for 31 days. The keeping quality of the curd yoghurts with addition of $15\%$ loquat extract was relatively good at $4^{\circ}C$ and $20^{\circ}C$ for 31 days.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.349-356
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• 2005

For the purpose of making a new type of functional drinkable yoghurt, skim milk containing $0.5\~2.0\%$(w/v) green tea powder was fermented by the mixed stains of Streptococcus thermophilus and Lactobacillus acidophilus. Quality characteristics of the drinkable yoghurts were evaluated in terms of quality-keeping properties(number of viable cells, pH, titratable acidity) and sensory properties. When the drinkable yoghurts added with $0.5\~2.0\%$ green tea powder were kept at $4^{\circ}C\;and\;20^{\circ}C$ for 20 days, the number of viable cell counts of the lactic acid bacteria($2.1\times10^8\~6.2\times10^8$ CFU/mL). pH($4.16\~4.22$) and titratable acidity($0.792\~0.881\%$) were not significantly changed for all drinkable yoghurts during the storage at $4^{\circ}C\;and\;20^{\circ}C$ days, but the number of viable cell counts($4.2\times10^3\~1.8\times10^5$ CFU/mL), pH($3.82\~3.92$) and titratable acidity($1.057\~1.174\%$) were markedly changed f3r the storage at $20^{\circ}C$ for 20 days. Therefore the keeping quality of the drinkable yoghurts with addition of green tea powder was relatively good at $4^{\circ}C$ for 20 days. The results of sensory evaluation of the drinkable yoghurts containing peen tea powder indicated that flavor, sweet taste, mouthfeel and aftertaste of the drinkable yoghurt with $0.5\%$ green tea powder showed higher preference than others. And the drinkable yoghurt containing $0.5\% green tea powder added $20\%$(v/v) oligosaccharide had the higher sensory scores in sweet taste, aftertaste and overall acceptability among the treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.926-934
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• 2006

The base for preparing oyster hydrolysate-added yogurt was consisted of whole milk (1,000 mL), skim milk (44.05 to 42.05 g), enzymatic oyster hydrolysates powder (OHP, 0 to 2.0 g) and pectin. The yogurt base was fermented with 7 kinds of starter cultures (3% based on yogurt volume), such as Lactobacillus acidophilus, lactobacillus bulgaricus, lactobacillus casei, Lactobacillus fermentum, Lactobacillus pentosus, Streptcoccus thermophilus and the mixed starters (L. bulgaricus and S. thermophilus) at optimal temperature. Processing condition and quality characteristics of the yogurt were evaluated by analyzing pH, titratable acidity, viscosity, viable cell count, functional properties and sensory evaluation. The results suggested that the optimal conditions for preparing the good quality yogurt revealed the mixed starters (L. bulgaricus and S. thermophilus) for starter culture, 1.0 g of 3 kDa hydrolysate for amount, and 5.5 hrs for fermentation time. The good quality yogurt showed 4.31 for pH, 1.07% for titratable acidity, 469 cps for viscosity and $4.9{\times}10^8\;CFU/mL$ for viable cell count. The hydrolysate-added yogurt was 2 times higher in ACE inhibitory and antioxidant activities than commercial yogurt, and kept good quality during storage of 15 days at $5^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.780-783
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• 1992

• Defense and Technology
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• no.1 s.167
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• pp.18-19
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• 1993

군사비가 경제발전에 미치는 영향을 분석해 보면 군사비나 경제개발 투자비의 문제가 아니라 군사비를 포함한 국가재정이 얼마나 효율성 있고 생산성 있게 쓰여졌는가가 중요한 문제입니다. 앞으로의 군사력 건설은 기술집약적 방위에의 방향으로 나아가면서 국방비 사용의 효율성(비용효율성)을 극대화하고, 동시에 경제적으로 파급효과도 크게끔 하는것이 요구된다 하겠습니다