• Journal of the Korea Institute of Building Construction
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• v.8 no.5
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• pp.59-65
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• 2008

In the evaluation method of KS on the activity factor of fly ash, same amount of cement should be replaced with fly ash. Therefore, contradictory effects on concrete strength exist, i. e. strength decease due to low content of cement and strength increase of strength due to filling-pore-function of fly ash. European Committee for Standardization (CEN) specifies the method 1 to 4. adding fly ash without reducing the content of cement, for the evaluation method on activity factor of fly ash. This study investigates the applicability of the method 2 of CEN to mix design of concrete. The followings are derived ; There is a key ratio of f)y ash mixing which enhances the incremental ratio of mixing water to improve fluidity of mortar. The incremental ratio of mixing water is maximized about 11% ratio of fly ash mixing. Compressive strength most slightly increases at that ratio of fly ash mixing. Activity factor of fly ash increases as water-cement ratio becomes low and contents of fly ash becomes high. Moreover, quality of fly ash and condition of mix design affect the applicable amount of fly ash and available range of water-cement ratio. However, this method has some problems for practical purpose because activity factors of fly ash for some cases are over 1.0. Further research should be conducted to develop more useful method of evaluating activity factor of fly ash.

• Journal of the Korean Geosynthetics Society
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• v.18 no.4
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• pp.253-262
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• 2019

This paper described the evaluation results on unconfined compressive strength characteristics of CLSM with paper sludge ash, in order to develop a CLSM that can prevent sewer pipe damage. The flowability test and the unconfined compressive strength test were performed according to mix design condition of CLSM. The flowability test result showed that the water content, which can satisfy the flowability criteria, was 24% to 32% according to the mix design condition. The results of unconfined compressive strength test showed that the strength incremental ratio was high between 1 and 7 days of curing time, and the strength at this time was more than about 50% of the strength at 28 days of curing time. The strength of CLSM was greatly influenced by fly ash. However, it was analyzed that the mixture of paper sludge ash is required when the reference strength of CLSM is considered. Although the strength of the high cement ratio was higher than that of the low cement, a cement ratio of 5% would be a reasonable mix design condition of CLSM.

• Journal of Aquaculture
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• v.6 no.3
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• pp.213-219
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• 1993

Two studies were carried out: to compare commercial flounder diets (C1-C6) with a laboratory-formulated diet (S), and to evaluate moist pellet (MP) prepared with or without raw fish for olive flounder culture. In experiment I, three replicates of 20 fish (42 g in average) each were fed S or each of C1-C6 for four weeks at $17^{\circ}C. For experiment 2, three replicates of 400 fish (78 g in average) each were fed $100\%$ laboratory-formulated grower diet (G), 50\%\;G+50\;%$ frozen mackerel containing $70\%$ moisture or $50\%\;C6$ (the same diet as that used in Exp. 1) +$50\%$ frozen mackerel for six weeks. Weight gain of fish fed S was significantly (P< 0.05) higher than that of fish fed C2 or C3 (26.7 vs 15.4 or 17.5g/fish over the 4-week period, respectively). Feed efficiency was significantly (p<; 0.05) lower in fish fed C2 than in fish fed S but was not different (P> 0.05) between the fish fed Sand the other commercial diets. No significant differences in weight gain were found among the fish fed $100\%\;G,\;50\%\;G+50\%$ frozen mackerel or $50\%$ C6+frozen mackerel. The results of our studies indicate that most of the commercial flounder diets can be improved for better growth, when we compared these diets with a laboratory-formulated diet, and the growth of flounder fed MP containing no raw fish was as good as that of those fed MP prepared with raw fish.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.82-94
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• 1988

This study was performed to obtain the basic data which can be applied to use of foaming mortars. The results obtained were summarized as follows ; 1. The lowest water-cement ratios were shown at the mixing ratio of 1 : 1. But, it was gradually increased in poorer mixing ratio and decreased in more addition of foaming agent. The water-cement ratios were decreased up to 1.6-53.1% by mix-foaming type and 4.4-24.1% by pre-foamed type than cement mortar. 2. The highest bulk densities were shown at the mixing ratio of 1 : 1. But, it was gradually decreased in poorer mixing ratio and more addition of foaming agent. The decreasing rates of bulk densities were increased in richer mixing ratio and more addition of foaming agent. 3. The bulk densities were decreased up to 38.8-55.9% by mix-foaming type and 9.7-23.6% by pre-foamed type than cement mortar. 4. The lowest absorption rates were shown at the mixing ratio of 1 : 1. But, it was gradually increased in poorer mixing ratio and more addition of foaming agent. The increasing rates of absorption rates were increased in richer mixing ratio and more addition of foaming agent. 5. Absorption rates when immersed in 72hours were shown up to 3.41-5.85 times greater by mix-foaming type and 1.05-1.55 times greater by pre-foamed type than those of cement mortar. it was significantly higher at the early stage of immersed time than cement mortar. 6. The highest strengths were shown at the mixing ratio of 1 : 1. But, it was gradually decreased in poorer mixing ratio and more addition of foaming agent. The decreasing rates of strengths were increased in poorer mixing ratio and more addition of foaming agent. 7. The strengths were decreased up to 77.0-92.8% by mix-foaming type and 36.7-74.4% by pre-foamed type than cement mortar. 8. The lowest air contents were shown at the mixing ratio of 1 : 1. But, it was gradually increased in poorer mixing ratio and more addition of foaming agent. The increasing rates of air contents were increased in richer mixing ratio and more addition of foaming agent. 9. Air contents were shown up to 26.0-63.8 times greater by mix-foaming type and 5.8-17.7 times greater by pre-foamed type than those of cement mortar. 10. The correlations between bulk density, absorption rate, compressive strength and air content were highly significant. The multiple regression equations of bulk density, absorption rate, compressive strength, tensile strength, bending strength and air content were computed depending on a function of mixing ratio and addition of foaming agent. They were generally highly significant.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.130-137
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• 1986

The five fish meal kojis which contained various ratios of barley were prepared and processed to produce six different fish-soy sauces. The chemical compositions including enzyme activities during fermentation were determined and sensory evaluation was done and changes of absorbance during heating process were also measured. The contents of reducing sugar increased until 12 hours, then slightly decreased and maintained constant level after 36 hours during koji making. The contents of total nitrogen were proportional to the amount of fish meal used in koji. The activities of amylase and protease were increased until 48 hours and then were not changed during koji making. The contents of reducing sugar were increased until 50 days and then were not much changed during koji making. The contents of nitrogen and amino nitrogen in sauces were increased gradually during fermentation. The total acid contents of sauces were increased until 70 days, after which it was constant during fermentation. The absorbances of sauces were increased with time during heating process. In sensory test, the fish-soy sauce the ratio of fish meal: barley of which was 10 : 16 received the highest score for flavor of sauce and the conventional soy sauce, for color and taste in a soup test. Fish-soy sauce resulted good quality when the ratio of fish meal to barley was 10 to 13 and 10 to 16.

• Microbiology and Biotechnology Letters
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• v.3 no.3
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• pp.123-134
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• 1975

Out of 96 yeast strains isolated from various natural habitats, five strains were screened based on their ability to ferment agricultural biproducts such as rice-, barley-and wheat-bran, and sawdust. These were identified as Hansenula anomala var anomala, Candide utilis, C. pelliculosa, Debaryomyces hansenii, and Irpex lacteus. Using these yeasts the above mentioned agricultural biproducts were fermented in various combinations. The fermented product was fed to 180 male Starcroses for eight weeks and obtained a body weight increase of 15.1g a day, while the unfermented control feed increased 10.5g a day.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.2
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• pp.111-115
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• 2007

It is inevitable to use germicidal agents like parabens, imidazolidinyl urea, phenoxyethanol and chlorphenesin to preserve the cosmetics. Although effective in reducing microblological contamination, chemical preservatives are irritative, allergenic and even toxic to human skin. So it is needed to decrease or eliminate usage of preservatives in cosmetic products Glycerin, butylene glycol (BG), prorylene glycol (PG), and dipropylene glycol (DPG) are widely used in cosmetics as skin conditioning agent or solvents. At high concentrations, they have antimicrobial activities, but deteriorate product quality like sensory feeling or safety. The purpose of study is to evaluate the effects of polyols on antimicrobial and preservative efficacy and confirm whether using adjusted polyols can decrease the contents of preservatives without deterioration of the quality of cosmetics. Effects of common polyols on antimicrobial activities of general preservatives were measured. BG and PG significantly (p < 0.05) increased activities of preservatives, but glycerin influenced little. It was inferred from the regression analysis of the results with S. aureus that adding 1% of PG increased activities of preservatives up to $2.1{\sim}8.4 %$ and BG improved activities of preservatives up to $1.8{\sim}8.4 %$. The challenge test results for oil in water lotions and creams showed that BG and PG improved the efficacy of preservative systems up to 40 % at a range of $5.5{\sim}9.9 %$, but glycerin had little effect on it. The measured rates of improvement were analogous to the inferences from regression analysis. It can be concluded that is possible to reduce total chemical preservatives up to 40 %, consequently improve the safety and sensory quality of cosmetics with the precision control of polyols. Added to that, using this paradigm, low preservative contents, praraben-free system, and even preservative-free systems can be expected in the near future.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.157-166
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• 2015

Purpose: The effects of water extract and distillate from the mixture of black goat meat and medicinal herb on MG-63 osteoblast proliferation and mouse bone marrow derived osteoclast formation were investigated. Methods: Proximate composition, volatile basic nitrogen (VBN), mineral content, free amino acid composition and free fatty acid composition in black goat meat were determined. Water extract and distillate were prepared with three groups; goat meat only (BG-E, BG-D), six herbs added group (BG-E6, BG-D6), and eight herbs added group (BG-E8, BG-D8). Osteoblast proliferation, mineralization and calcium uptake activity of MG-63 cells were measured and tartrate resistant acid phosphatase activity of osteoclasts was analyzed. Results: Black goat meat had remarkably low fat and high level of calcium. Glutamic acid was the most abundant amino acid. Herbs added extract groups (BG-E6 and BG-E8) showed increased MG-63 cell proliferation in a concentration dependent manner, while all the distillates did not show the effect. All extracts and distillates showed significantly increased osteoblast mineralization depending on the concentration. In particular, herb added extract, BG-E6, increased 170.3% of control and the distillate of BG-D and BG-D6 increased up to 168.5% and 159.8%, respectively. Calcium uptake activities of all water extracts showed remarkable increase of BG-E6 and BG-E8 up to 615.5% and 628.1% of control, respectively. Ditillates had no effect except BG-D6. All water extracts significantly reduced the activity of tartrate-resistant acid phosphatase (TRAP) in osteoclasts derived from mouse bone marrow. Conclusion: Combination of black goat meat and medicinal herb increased the MG-63 cell proliferation and effectively inhibited osteoclast differentiation in both water extracts and distillate of them, which implies that they could be used as potent functional food materials for bone health.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.121-125
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• 2007

물 수요예측을 실시함에 있어서 사회 경제의 장래동향과 도시의 특성 및 발전 동향을 반영하여 수행하여야 한다. 그러나 지금까지의 관행으로는 수도계획에서 사용할 수 있는 실사용량에 대한 조사와 통계가 이루어지지 않고 있다. 실제 현장에서 얻은 자료를 토대로 하여 수도계획 및 설계에 사용할 수 있는 신뢰성 있는 설계인자의 도출이 필요하다. 본 연구에서는 급수지역의 각 조사 가정의 물 사용량을 실측 조사하여 얻어진 자료를 토대로 하여 물 수요 구조의 변화를 파악할 수 있는 수단의 하나로 가정의 수돗물 사용특성과 경제적 요인에 따른 가정용수의 사용특성 경향을 파악하고자 하였다. 가정에서 사용된 용수량의 조건별 경향성을 분석하기 위하여 한국수자원공사에서 2002년부터 2006년까지 3년여에 걸쳐 표본 집단이 되는 전국 140개 가구에 유량계를 설치하여 유량 자료를 획득하였고, 설문조사를 실시하여 각 가정의 물 사용 특성인자들을 조사하였다. 이 자료를 대상으로 비교적 자료의 신뢰성을 높이기 위한 자료의 선별과정을 거쳤다. 이렇게 선별된 자료들을 경향성 분석에 쓰이는 Mann-Kendall test와 Spearman's Rho test를 이용하여 분석하였다. 그 결과를 바탕으로 가정 용수 소비패턴의 증가 감소에 영향을 끼치는 인자들을 추출하였다. 실측자료를 분석을 통하여 나타난 결과들을 바탕으로 용수 수요처의 조건별 특성을 분석하고, 이를 활용한 생활용수 예측모형을 개발함으로써 합리적인 수요예측에 의한 용수수요의 과다예측 우려를 해소하고, 경제적 수도시설계획을 수립하는 등 과학적 물 수요관리 정책 수립을 위한 의사결정도구가 제공될 수 있다.c}$C의 저온에서 저장한 감자는 $20^{\circ}$C에서 저장한 감자보다 발아의 지연과 함께 낮은 PGA증가율을 보였다.다 높았으며, 전반적인 선호도의 경우 G3(1.5%)를 가장 선호하는 것으로 나타났다. 백년초 분말 첨가 도토리묵의 경우 색상은 0.5% 첨가한 O1이 가장 높은 값을 나타냈으며, 외관은 1.5% 첨가한 O3가 가장 높은 값을 보였다. 향미와 신맛의 경우는 백년초 분말의 첨가량이 증가됨에 따라서 유의적으로 증가했다(p<0.001). 씹힘성, 탄력성, 견고성의 경우는 대조군이 가장 높았으며, 백년초 분말 첨가량이 증가함에 따라 유의적으로 낮아졌다(p<0.001), 떫은맛의 경우는 백년초 분말에 의한 신맛의 영향으로 1% 백년초 분말이 첨가된 O2 가장 높게 나타났다. 전반적인 선호도는 0.5% 백년초 분말이 첨가된 O1이 가장 높게 나타났다. 따라서 녹차와 백년초의 기능성을 살린 도토리묵을 실용화시키는 효과적인 배합비는 녹차 분말 1.5% 첨가와 백년초 분말 첨가 0.5%가 바람직한 것으로 보이며 백년초 분말은 1%까지도 가능한 것으로 나타났다. 그러므로 기능성 식품 소재로써 도토리묵에 녹차와 백년초 분말을 첨가하는 것은 충분히 활용할만한 가치가 있다고 사료된다.론적으로, 비육돈 사료 내 3.32%의 호맥 사일리지의 혼합급여는 혈액 내 코티졸 함량, 도체육의 명도와 황색도, 지방산 조성 및 영양소 소화율에 영향을 미치는 것으로 사료되나 이에 대한 보다 많은 연구가 필요할 것으로 판단된다.니티와 공원과의 관계로 공원 설계와 관리에 있어서 영국에서는 커뮤니티가 직접 고객(client)으로서 역

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.1
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• pp.11-21
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• 2013

The Geyoungju Ca-bentonite with dry density of 1.6 g/$cm^3$ has been considered as a standard buffer material for the disposal of high level waste in KAERI disposal system design. But it had relatively lower thermal conductivity compared with other surrounding materials, that was one of key parameters to limit the increase of the disposal density in the disposal system. In this study, various additives were selected and mixed with the Ca-bentonite in different mixing methods in order to increase the thermal conductivity from 0.8 W/mK to 1.0 W/mK. As an additive, CNT (Cabon Nano Tube), graphite, alumina, CuO, and $Fe_2O_3$ were selected, which are chemically stable and have good thermal conductivity. As mixing methods, dry hand-mixer mixing, wet milling and dry ball mill mixing were applied for the mixing. Above all, the ball mill mixing was proved to be most effective since the produced mixture was most homogeneous and showed higher increase in the thermal conductivity. From this study, it was confirmed that the thermal conductivity for the Geyoungju Ca-bentonite could be improved by adding small amount of highly thermal conductive material to 1.0 W/mk. In conclusion, it was believed that the experimental results will be valuable in the disposal system design if the additive effects on the swelling and permeability on the compact bentonite are also approved in further studies.