• Journal of the Korea Institute of Building Construction
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• v.12 no.2
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• pp.203-210
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• 2012

Recently, the interest and demand for large-scale buildings and skyscrapers have been on the rise, and the performance of concrete is an area of high priority. Securing 'mass concrete and high strength concrete' is very important as a key construction technology. For high strength concrete, the high heat of hydration takes place inside the concrete because of the vitality of hydration in cement due to the large amount of powder, and leads to problems such as an increase of thermal stress due to the temperature difference with the outside, which results in cracks and slump loss. For this reason, measures to solve these problems are needed. This study aims to reduce the hydration heat of high strength concrete to control the hydration heat of mass concrete and high strength concrete, by replacing the type of admixture, The purpose of this study is to control the hydration heat of high strength concrete and mass concrete. Our idea for this purpose is to apply not only the types and contents of admixture but also incorporation mixing water to ice-flake. As a result of the test, the use of blast furnace slag and fly ash as admixture, and the use of ice-flake as mixing water can improve the liquidity of concrete and reduce slump loss. Significantly dropping the maximum temperature will contribute greatly to reducing cracks due to hydration heat in mass concrete and high strength concrete, and improve quality.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.1-12
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• 2006

An existing Steel pipe, Cast iron pipe and Concrete pipe is can not escaped from aging, specially Metal tube is causing many problems that the quality of water worse is concerned about many rust and mike efficient use of preservation of water. The use of Glassfiber Reinforced Plastic Pipe(GRP PIPE) should be one of the possible scheme to get over these problems. The GRP PIPE has an excellent resistance power and the life is lasting from 50 to 100 years roughly. It's to be useful as a result of high durability and a good construction work also it is a light weight therefore can be expected to short the time of construction and man power. In this research, to executed the small-scaled model test, in-situ model test using CLSM of in-situ soil and to evaluated the stress - strain of the pipe also try to estimated how useful is. From the model test in laboratory, the vertical and horizontal deformation of the GRP PIPE measured in six instance using 200mm and 300mm in diameters. The value of experimentation, theory, analysis got the same results of the test, but the vertical and horizontal deformation gauged in small and the earth pressure was almost zero using CLSM of in-situ soil..

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.299-307
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• 1988

Several experiments were conducted to investigate the effects of external factors on germination and emergence of Eclipta prostrata (L.)L. The weight of viable achenes doubled as a result of 90 minutes soaking in water. The germination of E. prostrata was significantly improved by alternating temperatures. At a constant temperature of $35^{\circ}C$, only 78% of the achenes germination, whereas at alternating temperatures of 35/$20^{\circ}C$, 96.5% of the achenes germinated. E. prostrata was more sensitive than rice to moisture stress. No germination of E. prostrata achenes occurred in the absence of oxygen. No germination of E. prostrata achenes occurred in the dark or when they were exposed to green, blue, and far-red light. Germination of E. prostrata achenes was influenced by the duration of illumination after absorption of water. Ten hours of illumination was needed for maximum germination and 2 hours for 50% germination. No significant changes in germination of E. prostrata achenes were observed between pH 3 and 10. A high tolerance of E. prostrata achenes to salt was observed. Emergence of E. prostrata achenes was greatly affected by planting depth. In the upland soil, 74.0% of the achenes planted on the soil surface germinated, and no emergence was at planting depths of 0.5 cm or greater.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.429-436
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• 1984

To expand the utility of barley the experiments on the extrusion characteristics of barley flour for snack processing were carried out and the effects of the extrusion conditions on the quality of the extrudates were investigated. The optimum moisture content of barley flour for snack processing was 20%. The moisture content and the density of the extrudates decreased with increasing extrusion temperature and decreasing die size. The die swell ranged from 0.98 to 2.18 according to various extrusion conditions and decreased with increasing temperature above $150^{\circ}C$. The lightness, redness and yellowness increased at higher temperature. The water absorption index and the water solubility index showed their maximum values at $180^{\circ}C$.The gelatinization degree of the extrudates increased with increasing temperature. The fracture fore, Young's modulus and maximum fiber stress decreased, but the deformation to fracture increased, with increasing temperature and decreasing die size. The yield force in puncture test showed lower values at higher temperature. The size and the fraction of the air cells increased with increasing temperature and decreasing die size. The optimum extrusion conditions of barley for snack processing were at the temperature of $180^{\circ}C$, with the die size of 4.5mm when processed at 160 rpm.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.1
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• pp.80-87
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• 2001

Global robust diagnostic models are established based on MOM of GFDL to study the circulation in the world ocean. The horizontal grid sizes 1/2 degree, and the vertical water column is divided into 21 levels. The hydrographic data are taken from Levitus et al.(1994) and the wind stress from Hellerman and Rosenstein (1983). Based on the model results the horizontal volume, heat and salt transports across some representative sections are calculated. The preliminary results show that Though the cross-equator volume transports in the Atlantic, Indian and Pacific Oceans are all small, the heat transports across equator in the Atlantic are northward. This is clearly a result of the southward flow of the North Atlantic Deep Water and the northward compensating warm flow in the upper layer. The annual mean of the cross-equator heat transport in the Pacific Ocean from the present model is significantly lower than that calculated by Philander et at. (1987). This might indicate the importance of the Indonesian Throughflow in the heat transport in the Pacific Ocean. Our calculation shows that the heat transport through the Indonesian Archipelago is 0.5 PW, which is comparable with the poleward heat transport in the North Atlantic and Pacific Oceans. The difference in heat transports across the sections 5 and 6 demonstrates the important role of the Agulhas Current in the heat balance of the world ocean.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.694-700
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• 2007

Acanthopanax senticosus is a common Asian herb also known as "Siberian Ginseng". It is often used as a traditional herbal medicine for reducing damage in the liver, kidney, bone and muscle. In the present study we investigated the ferric reducing/antioxidant power and total phenolic contents of the ethanol-/water-extracts obtained from the stems and leaves of Acanthopanax senticosus. Osteoblast cellular proliferation was evaluated using the MTT and alkaline phosphatase activity assays in the human osteoblast-like MG-63 cell line. Acanthopanax senticosus extracts exerted remarkable ferric reducing/antioxidant power and contained high amount of phenolics. Among the extracts the stem-/ethanol-extract showed the highest antioxidant activity and total phenol content. Interestingly a highly positive correlation was found between antioxidant activity and total phenol content (p < 0.01). Proliferation of MG-63 osteoblast cells was highest in the stem-/ethanol-extract and alkaline phosphatase activity significantly increased in the water-extract of the stems (p < 0.05). These findings suggest that Acanthopanax senticosus extracts have antioxidant activity for preventing oxidative stress-related diseases and may have beneficial effects on bone health through the proliferation of osteoblast cells.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4763-4768
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• 2014

Recently, aluminum pipes have been used instead of steel pipes for open and shut machines in vinyl housing because of its corrosion-resistance and light weight. In particular, the light weight is very useful for fitting and removal by human resources. On the other hand, an aluminum pipe is weak in winter because aluminum has a larger thermal expansion coefficient than steel. This study examined the freezing and bursting of aluminum pipes by numerical analysis. The mechanical-thermal deformation characteristics were analyzed under the condition of ice volumetric expansion in aluminum pipes reaching 50%. From numerical analysis, large stresses above the yield stress occurred in aluminum pipe after ice expanded in the net diameter immediately. In addition, the freezing and bursting of aluminum pipes was predicted around an ice volumetric expansion of 6 - 7% because the thickness of the aluminum pipe reached an aluminum elongation ratio of 17%. Therefore, it is recommended that aluminum pipes be sealed perfectly to prevent water flow in the pipe. These results suggest that it is very difficult to prevent freezing and bursting of aluminum pipes by water freezing in the pipe.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.764-768
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• 2003

Resveratrol is natually occurring phytoalexin compounds produced by grape berries, peanuts, and their products in response to stress such as fungal infection, heavy metal ions or UV irradiation. The objective of this study was to develop a reliable high-performance liquid chromatographic method for the quantitative determination of trans-resveratrol in grape and its products. The trans-resveratrol was separated isocratically on Nucleosil 100-5 C18 column, using a mobile phase containing acetonitrile : water (40 : 60, v/v), detected by UV detector at 306 nm and the flow rate was 0.3 mL/min. Under this analytical condition, the recoveries of trans-resveratrol in grape, wine, and grape juice were 92.35, 104.72, and 91.08, respectively. Limit of detection in grape, wine, and grape juice were 14.5 ng/g, 3.62 ng/mL, and 4.02 ng/mL. Also, limit of quantitation in grape, wine, and grape juice were 14.8 ng/g, 3.69 ng/mL, and 4.10 ng/mL. Assay values of 32 grape varieties, 9 wines, and 9 grape juices were ranged from trace amount to $207.1\;{\mu}g/100\;g$, from 5.4 to $275.7\;{\mu}g/L$, and from 63.3 to $751.6\;{\mu}g/L$, respectively.

• Journal of Life Science
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• v.22 no.11
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• pp.1507-1514
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• 2012

Oxidative stress leads to damage in all components of the cell, including proteins, lipids, and DNA due to imbalance between reactive oxygen species production and cellular detoxification. Phytochemicals are well-known to contain antioxidants, and their physiological role has been intensively studied. The fruit of Cornus officianalis has been used in oriental medicine and has been reported to have many functions. In this study, four different extraction techniques were applied to extract functional components from the fruit of Cornus officianalis, and the content of loganin, which is an antioxidant having DPPH radical and hydrogen peroxide scavenging activity and reducing power, was analyzed in each extract. Extraction techniques employed in this study were heat extraction by water, 70% ethanol extraction, enzyme treatment, and combination of enzyme treatment and heat extraction by water. All extracts contained 11.8-18.0 mg/g loganin and showed antioxidation function assayed by measuring DPPH radical and hydrogen peroxide scavenging activity and reducing power. Among them, heat extraction was the most effective technique, showing a maximum amount of loganin (18.0 mg/g) and antioxidative activity at 100 mg/ml concentration. Each extract showed very low cytotoxicity up to at 500 mg/ml but 10-20% cytotoxicity at 1,000 mg/ml by in vitro MTT assay.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.131-138
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• 2003

A toxicological study of the pesticides for rice paddy to loach was conducted with iprobenfos 17% GR, diazinon 3 % GR, and butachlor 5 % GR to establish the field test method and their toxicological effects on loach under the actual field conditions. The type C of cage was more effective in the sense of a little stress from the cage. The nets for shading and for preventing the birds were necessary to maintain the water temperature and to prevent the predators. The cumulative mortality of loach exposed to iprobenfos 17% GR, diazinon 3% GR and butachlor 5% GR were 10, 55 and 22%, respectively, during 7 days of exposure. The averaged concentration of the pesticides in paddy water 2 days after application were 1.67, 0.22 and 0.26 mg/L, and mortalities were 7, 50 and 17%, respectively, representing the similar results with acute toxicity $(48h-LC_{50})$.