• 콘크리트학회논문집
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• 제12권5호
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• pp.25-34
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• 2000

When concrete is placed underwater, it is diluted with separating cementitious material and as a result the quality of concrete becomes poor. To solve this problem, antiwashout underwater concrete is increasingly used for the construction and repair of the concrete structure underwater. The objective of this study is to investigate the characteristics of antiwashout underwater concrete as to the mix proportion, casting and curing water through experimental researches. The unit weight of water and cement, water-cement ratio, fine aggregate ratio, unit weight of antiwashout underwater agent and superplasticizer, and casting and curing water were chosen to measure the suspended solids, pH, air contents, slump flow, unit weight of hardened concrete, and compressive strength. From this study, the incremental modulus at mix proportion design and unit weight of antiwashout underwater agent were increased more than fresh water, and it is a optimum mix proportion that the unit weight of water(and cement) is 230kg/$\textrm{m}^3$(460kg/$\textrm{m}^3$), waterOcement ratio is 50%, fine aggregate ratio is 40%, unit weight of antiwashout underwater agent is 1.2% of water contents per unit weight of concrete, and unit weight of supeplasticizer is 2.5% of cement contents per unit weight of concrete when the antiwashout underwater concrete is used for the underwater work of ocean.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.232-328
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• 2001

This paper investigates the influences of water content and viscosity agent on the bleeding of concrete. According to test results, fluidity shows decline tendency as water content decreases, and dosage of viscosity agent increases. PEO viscosity agent does not affect the air contents while, MC viscosity agent causes air loss. As for bleeding, bleeding decreases with decrease of water content. As dosage of viscosity agent increase, bleeding decreases, regardless of viscosity kinds. It is thought that viscosity agents have the favorable effect of reducing bleeding, if fluidity and air loss are improved.

• Journal of Ginseng Research
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• 제8권1호
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• pp.65-74
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• 1984

This experiment was carried out to study the effects of light intensity and soil water regimes on the growth of ginseng seedling. The results were as follows: 1. The maximum light intensity and optimum temperature in 1,le photosynthesis of ginseng seedling were 10,000 lux and 23 $^{\circ}C$. Respiration rate was increased at high temperature. 2. Air and soil temperature under the shading were increased as the increase of light intensity but soil water contents were decreased as the increase of light intensity, whereas air and soil temperature were decreased as the increase of precipitation under the shade b5: soil water contents were increased as the increase of precipitation under the shade. 3. The higher the transmittance of the shade, the greater the specific leaf weight (S.L.W.) and stomatal density. In contrast, however, the contents of total chlorophyll, chlorophyll a and b, and stomatal length was decreased. There was no any significant difference light intensity of the a/b ratio of chlorophyll. 4. The highest photosynthesis was occurred in ginseng leaves grown under the shade 5% L.T.R. and net photosynthesis rates increased with increasing soil water contents. 5. Optimum condition for usable seedling yield were 5% L.T.R. and 3.3% precipitation under the shade. Useless seedling increased with increasing precipitation under the shade.

• 한국식품영양학회지
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• 제35권2호
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• pp.96-105
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• 2022

This study compared and analyzed the antioxidant effect of Doenjang prepared from vegetable water, and explored the optimal addition ratio of vegetables of 5 kinds and the possibility of application to Doenjang. The sample is three kinds of vegetable water (VW1, VW2, VW3) prepared by adding different ratios of radish, carrot, green onion, onion and shiitake mushroom and Denjang prepared using it. Doenjang was aged and fermented at about 40℃ for 40 days, and then separated and used only solids. The content of their antioxidant compounds was measured the content of total phenolic acid contents and total flavonoid contents. In addition, the antioxidant effect was measured by electron donating activity, SOD-like activity, ABTs radical scavenging activity and reducing power. The total phenolic acid contents and total flavonoid contents were high at VW3 and that Doenjang made with VW3. Electron donating activity and SOD-liked activity were high at VW2 and Doenjang made with VW2. ABTs radical scavenging activity was high in Doenjang made of VW3, and Reducing power was high in VW3. Therefore, if Doenjang is prepared with vegetable water prepared by properly mixing 5 types of vegetables, the possibility of developing Doenjang with high antioxidant effect was suggested.

• 한국지반공학회논문집
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• 제18권4호
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• pp.309-317
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• 2002

본 논문은 경량기포혼합토(LWFS)의 역학적 특성에 대하여 연구하였다. 경량기포혼합토는 단위중량의 감소와 압축 강도의 증가를 위하여 연안준설토, 고화제 및 기포를 혼합하여 제작되었다. 초기함수비, 고화제 함유율, 양생조건 및 구속압 등 다양한 조건으로 경량기포혼합토를 제작하여 일축 및 삼축압축시험을 실시하였다. 경량기포혼합토의 실험결과는 동일한 단위중량일 경우 응력-변형 거동과 압축강도는 준설토의 초기함수비보다 고화제 함유율에 더 영향을 받는 것으로 나타났다. 한편 삼축압축시험에서 응력-변형 관계는 양생조건에 관계없이 변형-연화거동을 나타내었다. 구속압에 따른 응력-변형 거동은 경량기포혼합토의 일축압축강도와 근접한 구속압을 경계로 다르게 변화하는 것으로 나타났다. 압축강도 200kPa 이상으로 지반개량을 하기 위해 요구되는 경량기포혼합토의 배합비는 준설토의 초기함수비 100%~160%와 고화제 함유율 6.6%로 나타났다.

• 한국수산과학회지
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• 제11권3호
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• pp.129-138
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• 1978

The contents of inorganic conservative constituents in the downstream water were determined in spring tides of every month from May 1977 to April 1978 at eight stations of Nagdong River. Samples were taken at the intervals of one or two hours from 7 a. m. to 7 p. m. at each station. Annual ranges and means of the chemical constituents over all the stations except station one, Kupo, ate as follows: pH 6.4-9.3, 7.7; electrical conductivity $0.085-0.345\times10^3\;\mu\mho/cm,\;0.196\times10^3\;\mu\mho/cm;$ chloride 5.8-50.0ppm, 17.7ppm: fluoride ND-0.19 ppm, 0.06 ppm: sulfate 5.5-41.1 ppm, 20.7 ppm; calcium 6-26 ppm, 17 ppm; magnesium 2.0-12.8 ppm, 5.1 ppm; sodium 7-26 ppm, 13 ppm; potassium 1.4-3.8 pprn, 2.3 ppm respectively. The seasonal variations of contents of the chemical constituents were not large and showed nearly definite values at all the stations except station one, Kupo. At station one, seasonal variations were large and the contents were excessively high due to inflow of seawater compared with other stations. The values over 50 ppm in chloride were not determined during the determination period at Mul Geum where the intake station for Busan city water is located. Most constituents except pH and fluoride were over the criteria for drinking water at Kupo, while at other stations only pH value was exceeded the upper limit of the criterion especially in summer period. The pH values tended to increase in the afternoon when water temperature was high. The chloride concentration was shown the highest value at station one, Kupo, with about 2 hours delay after high water of Busan harbour and 3-3.5 hours at Mul Geum.

• 한국식품영양학회지
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• 제21권4호
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• pp.499-509
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• 2008

The purpose of this study was to investigate the changes in physicochemical and sensory properties of raw fruits during washing and chlorine treatments. Strawberry and banana were pre-prepared at different concentration of chlorinated water(0 ppm, 50 ppm and 100 ppm), immersion time(3 min and 5 min), and number of post-rinsing(1 time, 2 times and 3 times). The physicochemical properties such as pH, sugar contents, residual chlorine contents, color values and hardness of the fruits were analyzed, and the sensory quality were evaluated throughout the sterilization treatment process. After washing strawberry with 100 ppm chlorinated water and 3 times of post-rinsing, pH and residual chlorine contents were showed a little difference, while sugar contents, hardness, and color values(L, a and b) were reduced. In case of banana, pH, sugar contents and residual chlorine contents were not affected, and hardness and L color value were reduced. However, a and b color values of banana were gradually increased as the development of brown discoloration. Sensory properties of the samples were affected by the chlorine sterilization treatment. In overall acceptance, strawberry and banana treated with 100 ppm chlorinated water showed the lowest scores among treatments. Therefore it could be suggested that the application of 50 ppm chlorinated water for $3{\sim}5$ minutes with over 3 times of post-rinsing was the effective pre-preparation method without affecting the quality of the fruits.

• Preventive Nutrition and Food Science
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• 제19권2호
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• pp.124-127
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• 2014

The effect of feed moisture contents (30%, 40%, and 50%) and screw speed (200 rpm, 250 rpm, and 300 rpm) on the corn fiber gum (CFG) yield and soluble arabinoxylans (SAX) content of destarched corn fiber was investigated. The CFG yields and SAX contents of extruded, destarched corn fiber were higher than that of destarched corn fiber. In extruded, destarched corn fiber, increased screw speed and decreased feed moisture contents resulted in a higher SAX contents. The maximum yields of CFG obtained from extruded, destarched corn fiber were $79.1{\pm}19.0g/kg$ (30% feed moisture content) and $82.3{\pm}11.30g/kg$ (300 rpm screw speed). The highest SAX content was also observed at a screw speed of 300 rpm. The results of the present study show that water extraction and extrusion combined have the potential to increase CFG and SAX yields from corn fiber.

• Journal of Ginseng Research
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• 제6권2호
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• pp.115-122
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• 1982

This studies were conducted to investigate the effect of extraction and evaporating conditions on the free sugar in ginseng extracts. Raw ginseng roots were extracted with water or various concentration of water-ethanol solutions. Then the extracts were evaporated by boiling or vacuum evaporated at 50 $^{\circ}C$ and 70 $^{\circ}C$. The results are as follows Sucrose and maltose contents were 7.95% and 12.8% in water extracts and 19.96%, 0.34-0.93% in 90% ethanol extracts, respectively. On the otherhand, glucose and fructose contents were not affected by the solvents. Evaporating conditions, such as temperature, were rarely effected to the sugar contents.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.145-146
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• 2017

This research aimed to analyze the fundamental properties of cement mortar accompanying the change of the solid contents of the maintenance type PC water reducing agent. As a result of the experiment, it was found that the properties of fresh mortar show a tendency to decrease as the solid contents decreases in the case of flow and air contents, and the decrease width with time is small. It was found that the compressive strength of the hardened mortar has almost no difference due to the change of the solid fraction.