• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.631-641
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• 1998

The objectives of this study were 1) to classify the types of Quercus mongolica stands at Mt. Joongwang and compare their quality, and 2) to determine the proper future tree number of Q. mongolica per ha and the appropriate distance between the future trees. The results from this study were as follows : Q. mongolica stands at Mt. Joongwang was classified into four types, pure Q. mongolica stand as stand type I, Q. mongolica - hardwood stand as stand type II, Q. mongolica - Pines densiflora stand as stand type III, Hardwood - Q. mongolica stand as stand type IV, according to mixture rate in stand volume. Stand type IV showed the best quality stem of Q. mongolica among the stand types, and the stem quality of Q. mongolica in Q. mongolica stand mixed with hardwood as stand types II and IV was better than those in pure Q. mongolica stand as stand type I and in Q. mongolica - P. densiflora stand as stand type III. If the management goal for Q. mongolica stand is to produce its high quality-timber, it is desirable to sustain proper mixture rate of Q. mongolica with another hardwoods. The proper number of future trees in pure Q. mongolica stand as stand type I was 122trees/ha and reasonable distance between the future trees was 9.15m. The distance between future trees in other stand types was 7.2m to 9.3m for stand types II and IV, while 8.0m for stand type III. Thus, the classification of Q. mongolica stand type based on stand character and maturity, and proper stem number of future tree and optimum distance between future trees would be a useful forest tending work.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.525-530
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• 2011

Pine needles have long been used as a traditional health-promoting medicinal food in Korea. This study was carried out to investigate the effects of pine needle extracts on the antioxidant activity, and proliferation of osteoclastic RAW 264.7 cells. Pine needle extracts were examined using hot water, ethanol, hexane, hot water-ethanol, and hot water-hexane. The effects of the pine needle extracts were examined by comparing the results with that of a commercial agents, proanthocyanidin. Analysis of each extract indicated that hot water-ethanol and ethanol extracts contained the highest total polyphenol concentrations. The hot water-ethanol and ethanol extracts also showed relatively the highest SOD-like activity. The proliferation of osteoclastic RAW 264.7 cells treated with pine needle extracts was decreased by lower than 70%. In addition, the hot water and ethanol extracts of pine needle significantly reduced the number of tartrate-resistant acid phosphatase-positive ($TRAP^+$) multinucleated cells from osteoclatic RAW 264.7 cells. These results indicate that pine needle extracts had an anabolic effect on bone through the promotion of osteoclast differentiation, suggesting that they could be used for the treatment of common metabolic bone diseases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.517-524
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• 2011

Eleven polyphenolic compounds, including procatechuic and chlorogenic acids, (+)-dihydroquercetin, rutin, isoquercitrin, quercitrin, (+)-dihydrokaempferol, trans-resveratrol, moracin, quercetin and 4-prenylmoracin were isolated and purified from the methanolic extract of defatted mulberry seed residue by a series of column chromatography including silica gel, Sephadex LH-20, and ODS-A, and their chemical structures were identified by spectral analysis. The antioxidant activities of the eleven isolated polyphenolic compounds were measured spectrophotometrically using DPPH radical. Among the eleven polyphenolic compounds tested, rutin ($IC_{50}=20.2\;{\mu}M$), isoquercitrin ($IC_{50}=22.5\;{\mu}M$), quercitrin ($IC_{50}=24.6\;{\mu}M$), quercetin ($IC_{50}=27.8\;{\mu}M$), (+)-dihydroquercetin ($IC_{50}=28.9\;{\mu}M$), and chlorogenic acid ($IC_{50}=30.6\;{\mu}M$) exhibited stronger antioxidant activity than L-ascorbic acid ($IC_{50}=31.5\;{\mu}M$) and ${\alpha}$-tocopherol ($IC_{50}=52.3\;{\mu}M$), whereas procatechuic acid ($IC_{50}=68.2\;{\mu}M$) showed lower activity. In addition, (+)-dihydrokaempferol ($IC_{50}=33.8\;{\mu}M$), trans-resveratrol ($IC_{50}=36.2\;{\mu}M$), moracin ($IC_{50}=47.6\;{\mu}M$), and 4-prenylmoracin ($IC_{50}=48.2\;{\mu}M$) exhibited moderate antioxidant activity. Furthermore, levels of the eleven polyphenolic compounds from three different types of mulberry seeds were quantified by HPLC, and their contents were as follows: rutin (311~60.0 mg/100 g)> quercitrin (7.2~34.2 mg/100 g)> (+)-dihydroquercetin (13.2~33.1 mg/100 g)> quercetin (15.8~19.5 mg/100 g)> 4-prenylmoracin (10.5~43.3 mg/100 g)> isoquercitrin (5.8~15.4 mg/100 g)> chlorogenic acid (0.0~15.3 mg/100 g)> moracin (4.7~7.2 mg/100 g)> procatechuic acid (0.0~11.6 mg/100 g)> (+)-dihydrokaempferol and trans-resveratrol (<0.1 mg/100 g). The 'Daesungppong' mulberry seeds among the three cultivars had higher flavonoid contents, such as rutin and quercetin derivatives, while the 'Iksuppong' seeds had the highest contents of phenolic acids and moracin derivatives. 'Cheongilppong' had lower amounts of polyphenolic compounds than the other two mulberry seeds. These results indicate that mulberry seeds containing antioxidant polyphenolic compounds may be potentially useful sources of anti-diabetic, anti-hypertensive, and anti-aging agents for functional foods and cosmetics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.486-492
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• 2011

This study was designed to evaluate the effect of hot water extract (ESW) and 70% ethanol extract (ESE) from Euphorbia supina Rafin on LPS-stimulated inflammatory response in RAW 264.7 macrophages. Upon investigation at concentrations up to $1000\;{\mu}g$/mL, ESW and ESE did not have any cytotoxic effects on RAW 264.7 macrophages. ESW induced inhibition of 21.6%~54.8% of nitric oxide (NO) production at 100~1000${\mu}g$/mL, and $PGE_2$ production was inhibited up to 25.7%~38.2% at 250~1000${\mu}g$/mL, proportional to the ESW concentrations. ESW induced inhibition of 66.1% and 54.3% of IL-6 production at 250 and $1000\;{\mu}g$/mL, respectively. ESE (100~1000${\mu}g$/mL) induced inhibition of 38.3%~77.5% of NO, 40%~94.7% of $PGE_2$, and 43.9%~89.4% of IL-6 production, proportional to the ESE concentrations. Only 44.1% of IL-10 production was inhibited at a concentration of $500\;{\mu}g$/mL. ESE induced an increase in TNF-${\alpha}$ production at a concentration of 100 and $250\;{\mu}g$/mL, whereas at high concentrations (500 and $1000\;{\mu}g$/mL), ESE induced inhibition of 19.2% and 92.4% of TNF-${\alpha}$ production, respectively. In conclusion, concentrations of more than $500\;{\mu}g$/mL ESE demonstrated effective immune-modulating activity through inhibition of NO, $PGE_2$, IL-6, IL-10, or TNF-${\alpha}$ production, as it relates to the macrophage's immuno-activity; therefore, ESE has potential as a good candidate substance for reduction of inflammatory responses.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.276-281
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• 2008

Extracts from Rododendron mucronulatum Turcz. flowers were tested for antioxidant and their inhibitory activities of ${\alpha}$-amylase, ${\alpha}$-glucosidase and angiotensin converting enzyme (ACE). Total contents of phenolics were found as $30.6{\pm}0.14mg/g$ (60% EtOH extract) and $23.2{\pm}0.21mg/g$ (water extract). Electron donation ability (EDA), ABTS [2,2azinobis(3-ethylbenzothiazoline-6-sulfonic acid)] radical decolorization, Antioxidant protection factor (PF) and thiobarbituric acid reactive substance (TBARs) were measured for the antioxidative activity of the extracts from Rododendron mucronulatum Turcz. flowers. The water extract were determined as 97.5% at ethanol extract showed 83.2% and 60% EtOH extract were 89.7% in EDA. The water extract showed higher antioxidant activity than 60% EtOH extract when evaluated by ABTS radical decolorization and antioxidant PF. The TBARS of water extracts and 60% EtOH extracts were shown as $0.29{\times}10^2{\mu}M\;and\;0.28{\times}10^2{\mu}M$, respectively, and were lower than control. ACE inhibitory activity in water extract (67.6% inhibition) was higher than that of 60% EtOH extract (46.7% inhibition) at $200{\mu}g/mL$. Water extracts had higher inhibitory activities on ${\alpha}$-amylase and ${\alpha}$-glucosidase than 60% EtOH extracts. The result suggests that the water extract from Rododendron mucronulatum Turcz. flowers will be useful as natural antioxidants and functional foods.

• Journal of the Korean Geosynthetics Society
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• v.13 no.2
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• pp.1-10
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• 2014

In this study, two different types of dredged fill injection methods are introduced and filling experiments were conducted to analyze the impact of each technique to the distribution and deposition of dredged soil fill and how it influence the final tube shape. Two transparent plastic tubes were fabricated to observe the deposition behavior of the deposited fill material. Both tubes measured 4.0 meters in length (L) and has vinyl tube diameters (D) of 0.5m and 0.7m. T-type and I-type inlet system are also introduced in this paper. The influence of this inlet systems to the distribution and deposition behavior of dredged soil fill inside the vinyl tubes were observed during the experiment. After the sedimentation of the slurry mixture, the water on top of the soil sediments are removed and the slurry mixture was re-injected into the vinyl tube, this process was carried out repeatedly. The shape changes of the vinyl tube, e.g. the changes in both tube height and width, are constantly monitored after each slurry injection and water draining phases. Crater formation was observed in the case of I-Type inlet system and a non-uniform sediment distribution occurred. For the diffusion deposit of soil particles to long distance are minimal shape technique using the T-Type inlet system. Therefore the undrain filling height ratio ($H/D_0$) was found to be around 0.54 to 0.64 and the horizontal strain ratio ($W/D_0$) ranges from 1.45 to 1.54. The filling soil height is proportional to dredged-material filling phases, but, horizontal strain ratio is constant or inversely reduced so that the center of tube body is raised in the upward direction.

• Geotechnical Engineering
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• v.11 no.2
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• pp.29-36
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• 1995

Load testis are executed on model reticulated root piles (RRP) to figure out the optimum slanting angle in the piles installation. One set of model RRP consists of 8 slanting piles which are installed in circular patterns forming two concentric circles, each of which is made by 4 piles. Each pile which is a steel bar of 5m in diameter and 300mm in length is coated to become a pile of 6.5mm in diameter. The slanting angle of the model RRP varies from 0$^{\circ}$ to 20$^{\circ}$ Comparing ultimate bearing capacities of the model RRP of different installation angles, it is observed that the ultimate capacities of the RRP increase as the installation angle increases until 15$^{\circ}$, and the optimum slanting angle of the RRP is around 15$^{\circ}$ The ultimate bearing capacity of the 15$^{\circ}$-RRP is found to be 22% bigger than that of the vertical RRP and 120% bigger than that of the circular surface footing whose diameter is same with the circle formed by outer root piles'heads. However, it is noticed that when the slanting angle of the RRP is increased over 15$^{\circ}$, the ultimate capacity starts to be reduced. The ultimate capacity of 20$^{\circ}$-RRP is even smaller than that of the vertical RRP by as much as 5%. From the observation of the load settlement curve obtained during the RRP load tests, it is known that as the slanting angle gets bigger the load -settlement behavior becomes more ductile.

• Journal of Korean Home Economics Education Association
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• v.18 no.3 s.41
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• pp.23-40
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• 2006

The purpose of this study was to examine co-ed high school students' concern for appearance, weight control attitude and food behavior. The subjects were 405 students(boys 197, girls 208) in Sokcho area. Most of the students had much interest in appearance, and their perception of body type was significant differences between boys and girls(p<,00l). 22.8% of boys expressed satisfaction at their own body type. while just 9,6% of the girls were contented with their body type. In interest toward weight control. 43.7% of the boys and 79.8% of the girls had a regard for weight control. In relationship between weight control interest and the body type perception, there were significant differences among group of caring about weight control. moderate group and indifferent group(p<,00l), regardless of gender. As a whole, 41.3% of group that cared about weight control found themselves a little fat. Most of the boys who considered themselves thin(24,4%) were much concerned about weight control. where as girls who thought of themselves as thin were little interested in. Body type satisfaction was significant differences among interested group, moderate group and indifferent group(p<.00l). It appeared that they had breakfast very irregularly, But 86.9% of the total students had dinner, which indicated dinner was taken relatively on a regular basis. Among three meals, dinner was skipped the least, 23,5% (17.8% of the boys and 28,9% of the girls) went without breakfast everyday. For the reason, 65.1% of the overall students didn't eat breakfast due to time constraints, and lunch(39.8%) and dinner(31.3%) were skipped largely because eating them was troublesome. Less students went without meals to lose weight. and lunch(7.0%) was skipped more than breakfast(1.3%), and dinner(13,8%) was skipped more than lunch, This study suggested that nutrition education for high school students should be planned to provide nutrition information regarding desirable weight control as well as modifying diets and food behaviors.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.2
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• pp.113-126
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• 2011

This study was carried out to improve planting and use of landscape plants in Gangwon-do. The designated plants by schools and cities in Gangwon-do were surveyed and then compared with the planted trees on streets, public parks, schools, etc. in 2009. There were 45 tree species and 43 flower species designated as school trees and school flowers at 632 schools in Gangwon-do. The majority of school tree species were Juniperus chinensis, Pinus densiflora, Abies holophylla, Ginkgo biloba, Pinus koraiensis, Taxus cuspidata, Zelkova serrata, and Pinus thunbergii. The ratio of native species to exotic was 35:10. The majority of school flower species Rosa centifolia, Forsythia koreana, Zinnia elegans, Rhododendron mucronulatum, Chrysanthemum morifolium, and Rosa rugosa. The ratio of native species to the exotic was 22:21. There were 12 flower species and 7 tree species designated as city trees and city flowers in 18 cities and guns. The high frequency flower species were Rhododendron schlippenbachii, Forsythia koreana, Magnolia sieboldii, and Prunus armeniaca var. ansu. The high frequency tree species were Ginkgo biloba, Pinus koraiensis, and Taxus cuspidata. There were 87 woody landscape tree species planted, and a total of 619,835 landscape plants were planted in Youngseo region (western part of Gangwon-do) in 2009. The ratio of native species to exotic species was 56:31. The majority of landscape trees planted were Pinus densiflora, Prunus yedoensis, Prunus sargentii, Comus officinalis, Pyrus pyrifolia, Rhododendron yedoense var. poukhanense, Pinus koraiensis, Taxus cuspidata, Hibiscus syriacus, Forsythia koreana, Zellkova serrata, Acer triflorum, Rhododendron obutusum, and Ligustrum obtusifolium A in 2009. The ratio of native species to the exotic was 64:36. There were 77 woody landscape tree species planted, and a total of 914,668 landscape plants were planted in Youngdong region (eastern part of Gangwon-do) in 2009. The ratio of native species to exotic was 52:25. The major landscape trees planted were Pinus thunbergii, Rhododendron lateritium, Rhododendron schlippenenbachii, Hibiscus syriacus, Prunus yedoensis, Pinus densiflora, Syringa dilatata, Rhododendron yedoense var. poukhanense, Rosa rugosa, Prunus sargentii, Rosa centifolia, Juniperus chinensis, Euonymus japonica, Forsythia koreana, Chionanthus retusus, Acer palmatum, and Chaenomeles sinensis. The results indicate that landscape plants need to be diverse in species in each region of Gangwon-do. Selection of suitable plants for each region and the use of native species need to be emphasized.

• Journal of the Korean Institute of Gas
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• v.24 no.2
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• pp.1-8
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• 2020

Centrifugal pump is a facility that transfers energy to fluid through centrifugal force, which is usually generated by rotating the impeller at high speed, and is a major process facility used in many LNG production bases such as vaporization seawater pump, industrial water and fire extinguishing pump using seawater. to be. Currently, pumps in LNG plant sites are subject to operating conditions that vary depending on the amount of supply desired by the customer for a long period of time. Pumps in particular occupy a large part of the consumption strategy at the plant site, and if the optimum operation condition is not available, it can incur enormous energy loss in long term plant operation. In order to solve this problem, it is necessary to identify the performance deterioration factor through the flow analysis and the result analysis according to the fluctuations of the pump's operating conditions and to determine the optimal operation efficiency. In order to evaluate operation efficiency through experimental techniques, considerable time and cost are incurred, such as on-site operating conditions and manufacturing of experimental equipment. If the performance of the pump is not suitable for the site, and the performance of the pump needs to be reduced, a method of changing the rotation speed or using a special liquid containing high viscosity or solids is used. Especially, in order to prevent disruptions in the operation of LNG production bases, a technology is required to satisfy the required performance conditions by processing the existing impeller of the pump within a short time. Therefore, in this study, the rotation difference of the pump was applied to the ANSYS CFX program by applying the modified 3D modeling shape. In addition, the results obtained from the flow analysis and the curve fitting toolbox of the MATLAB program were analyzed numerically to verify the outer diameter correction theory.