• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.3
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• pp.82-93
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• 2008

In order to ensure a standardized data analysis of the eddy covariance measurements, Hong and Kim's quality control program has been updated and used to process eddy covariance data measured at two levels on the main flux tower at Gwangneung site from January to May in 2005. The updated program was allowed to remove outliers automatically for $CO_2$ and latent heat fluxes. The flag system consists of four quality groups(G, D, B and M). During the study period, the missing data were about 25% of the total records. About 60% of the good quality data were obtained after the quality control. The number of record in G group was larger at 40m than at 20m. It is due that the level of 20m was within the roughness sublayer where the presence of the canopy influences directly on the character of the turbulence. About 60% of the bad data were due to low wind speed. Energy balance closure at this site was about 40% during the study period. Large imbalance is attributed partly to the combined effects of the neglected heat storage terms, inaccuracy of ground heat flux and advection due to local wind system near the surface. The analysis of wind direction indicates that the frequent occurrence of positive momentum flux was closely associated with mountain valley wind system at this site. The negative $CO_2$ flux at night was examined in terms of averaging time. The results show that when averaging time is larger than 10min, the magnitude of calculated $CO_2$ fluxes increases rapidly, suggesting that the 30min $CO_2$ flux is influenced severely by the mesoscale motion or nonstationarity. A proper choice of averaging time needs to be considered to get accurate turbulent fluxes during nighttime.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.13-22
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• 2015

The study discovers mood state and enhancement effect of users by scenery of location targeting Seonyudo Park; where is widely recognized as the representative recycling environmental park as well as theme experience space and scenery admiration in Korea. Also, the influence level of park and thematic space upon wellness was researched for future park design and its base data. As a result of semantic differential(SD), the most items showed low point in positive way when people admiring the scenery in Seonyudo. Also, a subject experienced differently depending on each inside scenery element of the park. As a result of profile of mood states(POMS), a tension and anxiety points were shown in order of Urban (7.78) > Water Purification Basin(3.33) > Gardens of Water Plants(2.11) > Garden of Green Pillar(2.00) > Garden of Time (0.89). The depression points were shown in order of Urban(4.94) > Water Purification Basin(3.50) > Garden of Green Pillar(2.94) > Garden of Time(1.61) > Gardens of Water Plants(1.38). The anger and hostility points were shown in order of Urban(4.22) > Water Purification Basin(3.33) > Garden of Green Pillar(2.22) > Garden of Time(1.39) > Gardens of Water Plants(1.11). The fatigue points were shown in order of Urban(6.5) > Water Purification Basin(3.39) > Garden of Green Pillar(2.78) > Garden of Time(2.28) > Gardens of Water Plants (2.06). The vigor points were shown in order of Gardens of Water Plants(11.39) > Garden of Time(11.00) > Garden of Green Pillar(8.39) > Water Purification Basin(7.77) > Urban(5.28). Also, as a result of statistics analysis, difference value of scenery type is significant. The result of total emotional disturbance(TED) was analyzed in order of Urban(24.5) > Water Purification Basin(9.5) > Garden of Green Pillar(4.67) > Garden of Time(-1.39) > Gardens of Water Plants(-1.22).

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.3
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• pp.264-271
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• 1988

This experiment was carried out to investigate the effects of long-term applications of organic matters on the chemical properties and on the application levels of nitrogen in Fluvio-Alluvial plain of Jeonbug series. The amounts of application of rice straw and compost, the sources of organic matters, were 500 and 1,000 kg/10a in combined with the different nitrogen levels of 0.15 and 20 kg/10a, respectively. The results obtained from the 9 year's experiment during 1979 to 1987 were summarized as follows: I. In long-term application of Organic matter the soil pH showed the lowest value in the 3rd-4th year at rice straw and 5th-6th year at compost but it varied less in control plot for 9 years. 2. Organic matter content in the soils was gradually increased by yearly application of organic matter, while it was higher in rice straw than in compost since the 5th year. 3. The contents of available silica and available phosphate in soil were rapidly increased by long-term application of organic matter and it was especially higher in rice straw than compost, but it was gradually decreased in control plot. 4. The contents of exchangable cations (Ca, Mg and K) and the total nitrogen were increased by long-term application of organic matter they were in rice straw than in compost. But they showed decreasing tendency in control plot. 5. The soil Eh was lower in order of rice straw, compost and control plot however application of orgnic matter resulted in increasing soil Eh due to the rapid reduction of soil from panicle formation to heading stage in rice cultivation. 6. The number of panicles per $m^2$ and the number of granis per panicle were increased by increment of nitrogen levels in all treatments and especially largest in rice straw application. But 1,000 grain weight increased in low nitrogen level with long-term applications of organic matter. 7. It was estimated that the application levels of nitrogen by long-term application of organic matter were 21, 24 and 20 kg/10a for 1st-3rd, 4th-6th and 7th-9th year in rice straw application, and 16 and 19 kg/10a for 1st-3rd and 4th-9th year in compost application, respectively.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.114-120
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• 2006

Anti-diabetic effects of extracts and fractions of Sasa borealis (SB), white lotus roots (LR) and leaves (LL), and their mixture were determined in 3T3-L1 adipocytes and Min6 cells by investigating insulin-sensitizing activity and glucose-stimulated insulin secretion, respectively. SB, LR, LL, and mixture of SB, LR, and LL (3 : 2 : 3) were extracted using 70% ethanol, and m mixture extract was fractionated by XAD-4 column chromatography with serial mixture solvents of methanol and water. Fractional extractions were utilized for anti-diabetic effect assay. SB and LR extracts increased insulin-stimulated glucose uptake, but not as much as mixture of SB, LR, and LL. Significant insulin-sensitizing activities of 20 and 80% methanol fractions of SB, LR, and LL mixture extract were observed in 3T3-L1 adipocytes, giving 0.5 or $5\;{\mu}g/mL$ each fraction with 0.2 nM insulin to attain glucose uptake level similar to that attained by 10 nM insulin alone. Similar to pioglitazone, peroxisome proliferators-activated $receptor-{\gamma}\;(PPAR-{\gamma})$ agonist, 20 and 80% methanol fractions increased adipocytes by stimulating differentiation from fibroblasts and triglyceride synthesis. LL extract and 20, 60, and 80% methanol fractions of the mixture suppressed ${\alpha}-amylase$ activity, but did not modulate insulin secretion capacity of Min6 cells in both low and high glucose media. These data suggest 20 and 80% methanol tractions contain potential insulin sensitizers with functions similar to that of $PPAR-{\gamma}$ agonist. Crude extract of SB, LR, and LL mixture possibly improves glucose utilization by enhancing insulin-stimulated glucose uptake and inhibiting carbohydrate digestion without affecting insulin secretion in vivo.

• Journal of Nutrition and Health
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• v.17 no.2
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• pp.126-136
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• 1984

The long-term effects of vegetable and animal high fat diet on the lipid metabolism were investigated in male weaning rats. The rats were fed one of four semipurified diet ad libitum : control diet supplied 12% of calories as fat(control group), low fat diet supplied 3% of calories as fat (3% F group), 45% corn oil diet supplied 45% calories from corn oil (45% C group) and 45% butte. fat diet supplied 45% calories from butter fat (45 % B group). Incorporation of $acetate-1-^{14}C$ into lipid of liver, serum and adipose tissue as well as exhalation of $^{14}CO_{2}$ from $acetate-1-^{14}C$ were observed in rats fed for 4,8 and 12 weeks. The weigh of epididymal adipose tissue of rats, fed 45% corn oil and 45% butter fat . from 4 weeks to 8 weeks were higher, but not different at 12 weeks, compared with those of control group. The weight of abdominal adipose tissue appeared to be similar to those of epididymal adipose tissue. Incorporations of $acetate-1-^{14}C$ into lipid of liver were remarkably decreased in high fat diet groups, especially in 45% C group, but in 3% F group were increased more than those of control group. Incorporations of $acetate-1-^{14}C$ into epididymal adipose tissue in 3% F, 45% C and 45% B group at 8 weeks were remarkably increased but not different at 12 weeks, compared with those of control group. The incorporation of {acetate-1-}^{14}C into abdominal adipose tissue appeared to be similar to those of epididymal adipose tissue. Incorporations of $acetate-1-^{14}C$ into lipid of serum in 45% C and 45% B group were reduced reasonably at 4 and 8 weeks of diet as compared with those of control group. Exhalation of $^{14}CO_{2}$ was increased to maximum level at 10 minutes after injection of $acetate-1-^{14}C$. Expiration of $^{14}CO_{2}$ in 45% C and 45% B group were higher than those in 3% F and control group for initial 5 minutes after injection, but expirations of $^{14}CO_{2}$ did not have significant difference among groups of diet since 10 minutes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.409-419
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• 2016

The objective of this study was to investigate dietary sodium sources at the dish level in 228 university students (71 men, 157 women) in Gyeonggi-do. Daily sodium intake was estimated from a validated 125-dish frequency questionnaire. In men, body mass index, systolic blood pressure, and sodium intake were significantly higher than in women. Men showed higher sodium intake from soups, fish or shellfish dishes, meat dishes, and soybean dishes than women. The dishes that most largely contributed to daily sodium intake were Napa cabbage kimchi and ramen in both men and women. In addition, relatively higher amounts of sodium from ramen were consumed in men, whereas cookies were the 5th highest sodium source in women. In both men and women, the high sodium intake groups consumed more sodium from kimchi, dishes cooked with kimchi, dishes with broth, and salted mackerel than the low sodium intake group. There were significant differences in major dishes contributing to between-person sodium intake variations between men and women. Short rib soup for men and Korean sausage for women were the largest contributors to sodium variations, which are common dishes served with salt. Men consumed more drinks and also more sodium from drinks than women. In conclusion, there were significant differences in major dishes contributing to absolute and between-person sodium intake variations in university students between men and women. Further studies on effects of gender on blood pressure, sodium and drink intake, and obesity are necessary.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.4
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• pp.347-370
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• 2011

Slurry type shield would be very effective for the tunnelling in a sandy ground, when the slurry pressure would be properly adjusted. Low slurry pressure could cause a tunnel face failure or a ground settlement in front of the tunnel face. Thus, the stability of tunnel face could be maintained by applying an excess slurry pressure that is larger than the active earth pressure. However, the slurry pressure should increase properly because an excessively high slurry pressure could cause the slurry flow out or the passive failure of the frontal ground. It is possible to apply the high slurry pressure without passive failure if a horizontal impermeable layer is located in the ground in front of the tunnel face, but its location, size, and effects are not clearly known yet. In this research, two-dimensional model tests were carried out in order to find out the effect of a horizontal impermeable layer for the slurry shield tunnelling in a saturated sandy ground. In tests slurry pressure was increased until the slurry flowed out of the ground surface or the ground fails. Location and dimension of the impermeable layer were varied. As results, the maximum and the excess slurry pressure in sandy ground were linearly proportional to the cover depth. Larger slurry pressure could be applied to increase the stability of the tunnel face when the impermeable layer was located in the ground above the crown in front of the tunnel face. The most effective length of the impermeable grouting layer was 1.0 ~ 1.5D, and the location was 1.0D above the crown level. The safety factor could be suggested as the ratio of the maximum slurry pressure to the active earth pressure at the tunnel face. It could also be suggested that the slurry pressure in the magnitude of 3.5 ~4.0 times larger than the active earth pressure at the initial tunnel face could be applied if the impermeable layer was constructed at the optimal location.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.91-103
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• 2012

The aim of this study was to develop a rapid and cheap bioassay of four lignans (schisandrin, schisandrin C, the gomisin A and gomisin N) isolated from Schizandra chinensis Baill on seed germination and seedling growth of the radish. Its structure was determined by analysis of MS and NMR spectroscopic data. Radish seeds immersed for 1 hr in the solutions of $10^{-5}M$, $10^{-6}M$ and $10^{-7}M$ of schisandrin, schisandrin C, gomisin A, and gomisin N, seed germination was observed with in 60 hr after all of the treatments. Also, the seeds were germinated faster compared to untreated controls. At early germination stage, 48 hr after the treatment of the lignans, the suppression of germination was observed from all treatments; the suppression due to schisandrin and gomisin A was the highest at the concentration of $10^{-6}M$. The level of suppression increased as the concentration increased in the treatment of schisandrin C and gomisin N. Percent germination of seed after 184 hr was increased 90% at all treatments. For the effects of lignan treatment on seedling growth in radish, the growth of hypocotyl was promoted by gomisin A and gomisin N at all concentrations. Root elongation was significantly promoted by schisandrin and gomisin N at $10^{-5}M$ and $10^{-6}M$, respectively. Fresh and dry weights of the seedlings were high at a low concentration of $10^{-7}M$, but significantly reduced by schisandrin C at a high concentration of $10^{-5}M$. The results of the germination activity and seedling growth of the lignans from S. chinensis suggest their potential use as natural growth regulators.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.1-7
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• 2001

Total upland area for cultivating the vegetable crops in the Alpine soils of Northeastern South Korea has been extending its limit to meet the increasing demand of vegetable food in recent decades. About 70% of these alpine soils are located in over 7% of the slope and most of vegetable crops have been cultivated intensively without practicing the best management systems. Thus, soil erosion and continuous cropping system have degenerated the soil fertility and shown detrimental effects on water quality. We initiated an intensive and extensive investigation to characterize the fertility problems encountered in these uplands. Objectives of this paper were to characterize the fertility status in the Alpine soils cultivated with vegetable crops for many years and to provide the recommendations for adequate soil management measures including fertilization and erosion control. Soils in general have good drainage with textural classes of loam or sandy loam. Their topographical characteristics tended to lead them to shallow plow layers, and the steepness of the terrain created erosion hazard. Of the soils examined, about 11% of uplands over 30% gradient was found in need of an urgent reforestation. A high content of gravel and firm hardness of soil attributed to inhibit the utilization of farm machinery and plant-root development. The average soil pH 5.6 was slightly low relative to pH 5.70 of the national average. Organic matter content was high compared with 2.0% of national average, but decreased with the prolonged cultivation periods. Available $P_2O_5$ concentration was unusually high due to the consequence of over dose application with chemical and organic fertilizers. Exchangeable cations as Ca, Mg, and K were appeared to be decreased in these regions with prolonging the cultivation periods. There were no significant differences in cation exchange capacity (CEC) and electrical conductivity (EC) among locations. Heavy metal contents were mostly lower than the threshold of danger level designated by Soil Environment Conservation Law of South Korea. Results indicated that a proper countermeasure and the best management practice should be immediately implemented to conserve the top soil and fertility in the Alpine regions.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.688-694
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• 2021

Turanose is a potential candidate for use as a functional sweetener because of its gentle taste, low calorie, and non-cariogenicity. The aim of this study was to replace sucrose with turanose to produce health-beneficial maesil-cheong. Quality effects of turanose on maesil-cheong were evaluated by determining the contents of free sugars, organic acids, amygdalin, and antioxidant activity. The pH and Brix values of sucrose- and turanose-based maesil-cheong remained at the same level between 2.83 and 3.00 and 54.6-58.6°Bx, respectively, after 90-day storage. Among oxalic, malic, and citric acids, citric acid content was the highest in both maesil-cheong samples. Turanose did not significantly hydrolyze in maesil-cheong, whereas sucrose was completely hydrolyzed to glucose and fructose. Thus, turanose is suitable for the development of acidic maesil-cheong to improve its health promoting effect. Turanose showed product qualities similar to sucrose-based maesil-cheong. Turanose can be used as a functional sweetener or bulking agent in processed foods.