• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.7-13
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• 1989

The present study was carried out to get the basic information for clarifying physiological mechanism of breaking dormancy and sprouting in Panax ginseng roots. Changes in Abscisic acid (ABA) content and Gibberellin (GA) activity were investigated in one-year-old root during stratification at 4$^{\circ}C$. 15$^{\circ}C$. and 15$^{\circ}C$ after 60day-treatment at 4$^{\circ}C$. Sprouting rate at 15$^{\circ}C$ was 35％ in 30days storage at 4$^{\circ}C$ and 100％ in longer than 60days, but there was no sprout in both the constant treatment at 4$^{\circ}C$ or 15$^{\circ}C$ regardless of the treatment period. The longer the period of low temperature treatment. number of days to the first and 50％ sprouting was shortened, and number of days to 50％ from first sprouting was also shortened. ABA content in the upper part of root(contained bud) was gradually increased at both 4$^{\circ}C$ and 15$^{\circ}C$ as the treatment period was extended. and the degree of increase was higher at 15$^{\circ}C$. In the lower part. it showed a slight increase at 15$^{\circ}C$. while showed little change at 4$^{\circ}C$ throughout the treatment period. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$, it was greatly increased in the upper part. while rather slightly decreased in the lower part of root. GA activity in the upper part was gradually decreased at both 4$^{\circ}C$ and 15$^{\circ}C$, and the degree of decrease was higher at 15$^{\circ}C$. In the lower part. it was similar tendency to those in the upper part. In the 15$^{\circ}C$ treatment after 60days at 4$^{\circ}C$. it was remarkably increased in both the upper and lower part. The increase was great in the low Rf region, while the decrease appeared relatively in the high Rf region compared to those of 60day-treatment at 4$^{\circ}C$. The above results indicated that the breaking dormancy and sprouting of bud were closely associated with the degree of GA activities in response to temperature condition .during stratification rather than the direct effect associated with the changes in ABA content.

• Journal of Conservation Science
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• v.24
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• pp.1-11
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• 2008

The Unhyungung Water Container in the possession of the Seoul Museum of History in Korea is consisted of a calcareous marble developed laminated bedding and numerous argillaceous veinlets. This monument should need to conservation treatment because of black discoloration and seriously numerous cracks. Vertical and horizontal cracks in the monument are developed following stratification and argillaceous veinlets that are relatively low coherence between the rock materials. We have proved that the material inducing discoloration on the surface is carbon which is formed by deposited organic matters. As the result of the ultrasonic measurements, although highly surface weathering degree, the physical properties of the Unhyungung Water Container is confirmed slightly weathered state. The depths of cracks in the monument are calculated at maximum 60mm in some cracks completely penetrating into the wall and at minimum 9mm in the other crack. The cracks, developed following veinlet, are revealed that there penetrate from an outer wall to an inside wall for the monument. And most depths of cracks, developed following stratification, are calculated 20 to 30mm. This result will offer a significant data for conservation of the Unhyungung Water Container.

• Journal of Korean Society on Water Environment
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• v.34 no.5
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• pp.447-461
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• 2018

To realize river restoration that ecological characteristics of the river are reflected, we classified the river into four reaches of valley stream, upstream, midstream, and downstream based on substrate as well as riverbed gradient obtained from the relationship between distance from the river mouth, and above sea level. Considering that the rivers of Korea have been dominated by various and intense artificial interferences over a lengthy period, we determined cross sectional range of the river based on the geological map and clarified transformation degree by reach. Vegetation profile diagram was prepared by depicting horizontal range and vertical stratification of major vegetation appearing in a belt transect of 10 m breadth installed between weirs constructed in both sides of the river. Restoration models by river reach were prepared based on breadth of waterway, bare ground, herb, shrub, and tree dominated vegetation zones on vegetation profiles wherein a flooding regime was reflected. Species composition information collected from vegetation established in each zone was systematized to use for restoring each reach ecologically. Further, background that longitudinal reaches and horizontal zones were divided, was discussed by comparing with case studies in foreign countries. In addition, necessity of ecological restoration of the river was discussed based on degree of integrity of Korean rivers, ecological significance of riparian vegetation, and importance of reference information for ecological restoration of the river.

• Journal of Korean Society of Forest Science
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• v.7 no.1
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• pp.40-44
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• 1968

1. The larvae of the pine gall-midge begin to grow slowly from early July but grow rapidly from September. 2. The number of larvae in the galls does not decrease during the feeding period. 3. Pine needles infested by pine gall-midge cease to grow as soon as the gall starts to form. 4. In Seoul district the effective felling season of the pine trees for the Control of the pine gall-midge seems to be around 20th September when the size of larvae reaches 1.4-1.5mm in length. 5. The stratification and direction of the Crown, and the length of new shoot had no effect on the degree of infestation by pine gall-midge. However the degree of infestation differed among the trees of different ages as well as at the different levels of the mountain.

• Water for future
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• v.28 no.2
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• pp.137-143
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• 1995

The location and the shape of freshwater-saltwater transition zones in coastal aquifers are affected by many hydraulic variables. To date most work to determine the effects of these variables are limited to qualitative comparison of transition zones. In this work characteristics of transition zones (maximum intrusion length, thickness, and degree of stratification) are quantified, and effects of principal hydraulic variables(velocity and dispersivity) on these characteristics are studied using a numerical model. Dimensional analysis is used to assemble entire model results. Effects of velocity and dispersivity are seen clearly. From this study, increase in velocity is found to cause shrinkage of transition zones. This observation contradicts claims by some that, because dispersion is proportional to velocity, increase in velocity would cause expansion of transition zones.

• Asian Journal of Turfgrass Science
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• v.16 no.2
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• pp.107-114
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• 2002

In this study, We measured air temperature in a vegetated area to investigate if stand types and height affect air temperature. With the measured data, we analyzed the relation-ships between air temperature vs. ground cover type, vegetated area, stand structure, stand density, and tree volume by regression analysis. The results show that the paved area and open field have higher air temperatures than the vegetated area and water-related areas. Among the stand types, the stand with overstory and sub-overstory showed relatively low are temperature. The stand with overstory had lower air temperature than the stand with sub-overstory. Increasing stand density was effective for lowering air temperature.

• Journal of the Korean Society of Clothing and Textiles
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• v.2 no.2
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• pp.253-260
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• 1978

The purpose of this study was to investigate whether or not the clothing behavior of house-wives in Seoul vary depending on their socioeconomic status. The null hypotheses tested in this study were as follows: 1) There are no differences in housewives' attitudes toward the importance of clothing according to their socioeconomic status. 2) There are no differences in housewives' criteria of clothing choice according to their socioeconomic status. 3) There are no differences in housewives' clothing taste according to their socioeconomic status. 4) There are no differences in the pattern of housewives' clothing purchase according to their socioeconomic status. In order to test these null hypotheses, questionnaires on clothing behavior and socioeconomic status were distributed to a sample of 243 purposively selected housewives in Seoul, Korea. The factor analysis, correlation and analysis of variance techniques were employed for the statistical analysis of data. The results indicated that: 1) The attitudes toward the importance of clothing was related to socioeconomic status. 2) The criteria of clothing choice (aesthetics-practicality), clothing taste (individuality-conformity), and the pattern of clothing purchase (a degree of rationality) were not related to socioeconomic status. 3) The criteria of clothing selection was related to housewives' level of education. 4) Clothing taste was related to housewives' age.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.9
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• pp.1272-1280
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• 2001

An experimental study has been conducted to elucidate the resonance of natural convection in a side-heated square enclosure having a mechanically oscillating bottom wall. Under consideration is the impact of the imposed oscillating frequency, amplitude and the system Rayleigh number on the fluctuation of air temperatures. The experimental results show that the magnitude of the fluctuation of air temperature is substantially augmented at a specific forcing frequency of the oscillating bottom wall. The resonant frequency is increased with the increase of the Rayleigh number and it is little affected by the amplitude of the oscillating wall. It is also found that the resonant frequency is relevant to the Brunt- V$\"{a}$iS$\"{a}$l$\"{a}$ frequency which represents the stratification degree of the system.

• Nuclear Engineering and Technology
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• v.32 no.2
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• pp.142-156
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• 2000

An experimental study of steam condensation on a subcooled thick water layer (0.018 ~0.032 m) in a countercurrent stratified flow has been performed using a nearly horizontal circular pipe. A total of 103 average interfacial condensation heat transfer coefficients were obtained and parametric effects of steam and water flow rates and the degree of subcooling on condensation heat transfer were examined. The measured local temperature and velocity distributions in the thick water layer revealed that there was a thermal stratification due to the lack of full turbulent thermal mixing in the lower region of the water layer Two empirical Nusselt number correlations, one in terms of average steam and water Reynolds numbers, and the water Prandtl number, and the other in terms of the Jakob number in place of the Prandtl number, which agree with most of the data within $\pm$ 25%, were developed based on the bulk flow properties. Comparisons of the present data with existing correlations showed that the present data were significantly lower than the values predicted by existing correlations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.334-341
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• 1990

The electrophoretic variations in protein and some enzymes during stratification of Panax ginsseng seeds were checked in relation to the differentiation and development of immature embryo, Seed-protein on PAGE showed eight major bands during the period of investigation, Four bands of Rf : 0.12, 0.24, 0.66 and 0,72 remained in dark stained condition, whereas the remainders (Rf : 0.40, 0.48, 0.56 and 0,76) became lighter in the staining condition as the treatment period was prolonged, In embryo, which was separately sampled from 75 days after the treatement, the only band of Rf 0.76 was not observed, In peroxidase, the number of bands was gradually increased and came to four bands at 45 days after treatment, and their staining color became gradually darker until the time of final samling. Also, the embryo had the same patterns as those in the intact seed. Esterase showed four bands during the period of investigation. As the treatment period was prolonged, the degree of staining condition came to darker in the band of Rf 0.36, but lighter in the band of Rf 0.56. The band of Rf 0.20 was not detected in the intact seed at 90 days after the treatment, but clearly observed in embryo. Glutamate dehydrogenase had only two bands: one (Rf : 0.16) was detected only at 60 days after the treatment and the other (Rf: 0.14) was always observed throughout the period, and showing simple pattern in the electrophoretic variation. Glutamate-oxaloacetate transaminase showed the only band of Rf 0.36 during the period of investigation and even in embryo, and showing the simplest pattern, indeed.