• Proceedings of the Korean Society of Crop Science Conference
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• 1997.10a
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• pp.90-91
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• 1997

• Proceedings of the Korean Society of Crop Science Conference
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• 1988.02a
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• pp.106-107
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• 1988

• Journal of the Korean Wood Science and Technology
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• v.32 no.3
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• pp.1-7
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• 2004

The application of abrasive-assisted high energy water-jet was investigated as a possible new method of cutting wood. In this study the maximum cutting speeds for species of various wood density were determined and water-jet machining characteristics were investigated for sixteen Korean domestic species. The maximum cutting speed ranged from 200 to 750 mm/min. The results indicate that wood density affects machining characteristics such as maximum cutting speed, surface roughness, and kerf width. Roughness of surface generated increased and kerf width decreased as penetration depth increased.

• Korean Journal of Agricultural Science
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• v.5 no.1
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• pp.29-34
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• 1978

In order to improve atomization of droplet of sprayers, gun-type nozzle equipped with swirl screw which could increase tangential velocity had been used in this study. The results obtained were as follow: The larger diameter of atomized droplet was, the longer it reached. Tile atomizing phenomenon while using swirl screw in the nozzle was more efficient. There was little difference of travelling distance in the both nozzles when the small diameter of disk hole was used, but thetravlling distance of the nozzle with swirl screw was evidently getting shorter with the increase of the hole diameter compared to that of the nozzle without swirl sorew. The size of sprayed particles was getting smaller owing to the phenomenon of air movement the one to two meters travelling distance of droplet from maximum travelling point.

• Korean Journal of Agricultural Science
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• v.5 no.1
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• pp.1-5
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• 1978

Aseptic meristem of Fragaria ananassa 'Hokowase' were inoculated on Murashige and Skoog medium containing various levels of Benzylamiro purine(BA), IAA, and 2.4-D. Formations of shoots plantlets, roots and callus depend on hormone levels used. On medium containing high level of BA 1.0mg/l, multiple plantlets were formed, however, elongation of shoots was inhibited than on BA 0.5 mg/l. 1.0mg/l IAA induced root formation and 1.0mg/l+1.0mg/l BA inhibited root formation. Callus formation was occurred on the medium added 2.4-D. When plantlets were subcultured, formation of callus or shoot depend on BA/2.4-D ratio. 2.0mg/l 2.4-D+0.2mg/l BA and 0.5 mg/l 2.4-D+0.2mg/l BA induced callus formation and 2.0mg/l BA induced plantlet and shoot vigorously.

• Korean Journal of Agricultural Science
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• v.5 no.1
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• pp.7-14
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• 1978

The experiment was carried out in order to choose fungicides which are proper to be used in flowering time of fruit trees. The effect of fungicides on pollen germination and pollen tube growth was investigated in vitro. The results obtained are as follows : 1. Difolatan-Wp, Lime-sulfur, Captan-Wp and Bordeaux mixture greatly inhibited pollen germination and pollen tube growth. 2. The effect of Daconil-Wp and Zimaneb-Wp on pollen germination and pollen tube growth was not so great as that of Difolatan-Wp, Lime-sulfur, Captan-Wp or Bordeaux mixture. 3. Polyram-combi-Wp, Topsin-Wp and Benlate-Wp did not affect pollen germination but these fungicides slightly inhibited pollen tube growth. 4. Polyoxin-Wp significantly increased pollen tube growth but did not show promotive effect on pollen germinaiton.

• Journal of Korean Society of Forest Science
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• v.45 no.1
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• pp.46-50
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• 1979

The morphological differences of pollen of genus Weigela in Korea were examined at different dates and localities, and following results were obtained : 1. Variations in pollen size were distinct among the four species examined. Pollen sizes of W. florida being the largest and W subsessilis the smallest. 2. The same species showed difference in pollen sizes at different dates and localities, and pollen size of W subsessilis which was collected in autumn was the smallest. 3. Variation in the P : E index was relatively small in each collection, the shapes of W. subsessilis and W. hortensis being suboblate and those of W. florida and W. praecox spheroidal. 4. Pollens of four species In Mt. Gyeryong had three porate, but W. subsessilis in Mts. Kwanak and Bomun had four.

• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.361-365
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• 1999

This atudy was conducted to determine the growth characteristics and photosynthesis of soybean (Glycine max L. cv. Keumjongkongl) 30 day old seedling to 100mM NaCl concentration containing 1/2 Hoagland`s nutrient solution in sand culture. The nodule formation of root is not found perfectly with NaCl stress. The leaf dry matter weight (g/plant) of stressed plant is more reduction in 77% to control than any other characters. The water content (%) is tend to increase but water potential (MPa) is tend to decrease at NaCl stress. The chlorophyll content (SPAD) is tend to increase at growing leaf age of control but decrease at NaCl stress. The photosynthesis, stomatal conductance and transpiration are tend to decrease sharply at NaCl stress.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.2
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• pp.107-113
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• 1976

This study is conducted to find out soil erodibility factor K value which is one of the most important factor to estimate soil loss using a new method for predicting K value, the nomograph, that was first proposed by Whischmeier. K values for 83 soil series including upland and forest soils in Korea were checked up. The result were as follows: The average K value was 0.27 with ranging between 0.05 and 0.51. K values were higher for finer textured soils than for coarser textured soils widely ranged in a textural class, and higher for silty textured and low permeable soils. K value was correlated inversely with organic matter content in range of 3 to 13 percent, but the tendency was not related in range of lower than 3 percent.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.1
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• pp.27-36
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• 2017

Angelicae Gigantis Radix (AGR, Angelica gigas) has been used for a long time as a traditional folk medicine in Korea and oriental countries. Decursinol angelate (DCA) is structurally isomeric decursin, one of the major components of AGR. This study was performed to confirm whether DCA augments pentobarbital-induced sleeping behaviors via the activation of $GABA_A$-ergic systems in animals. Oral administration of DCA (10, 25 and 50 mg/kg) markedly suppressed spontaneous locomotor activity. DCA also prolonged sleeping time, and decreased the sleep latency by pentobarbital (42 mg/kg), in a dose-dependent manner, similar to muscimol, both at the hypnotic (42 mg/kg) and sub-hypnotic (28 mg/kg) dosages. Especially, DCA increased the number of sleeping animals in the sub-hypnotic dosage. DCA (50 mg/kg, p.o.) itself modulated sleep architectures; DCA reduced the counts of sleep/wake cycles. At the same time, DCA increased total sleep time, but not non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. In the molecular experiments. DCA (0.001, 0.01 and $0.1{\mu}g/ml$) increased intracellular Cl- influx level in hypothalamic primary cultured neuronal cells of rats. In addition, DCA increased the protein expression of glutamic acid decarboxylase ($GAD_{65/67}$) and $GABA_A$ receptors subtypes. Taken together, these results suggest that DCA potentiates pentobarbital-induced sleeping behaviors through the activation of $GABA_A$-ergic systems, and can be useful in the treatment of insomnia.