• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.444-451
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• 1999

The effect of individual density on the growth and survival of Laminaria japonica was experimentally evaluated. Four density treatments of young sporophytes (0.63 cm In maximum length) grown in the laboratory were transplanted to the southeastern coast of Korea and their survivorship and growth rate were measured twice a month from January to July, 1996. Plants showed higher survivorship at low density. Final densities at three lowest densities were similar, ranging from 34 to 38 inds${\cdot}100 cm^{-2}$. Planis at the highest density, however, suffered greater decline than at lower densities, and only 21 plants remained at the end of this study. Mean frond size (length and width) fluctuated throughout the study period at four densities. During the first two mouths after outplanting, mean frond size was negatively correlated with initial density, However, the size was density independent after three months. As stand density increased, size-frequency distribution through time tended to be more positively skewed. The 10 largest plants grew faster in frond size and attained larger size in the lower density. There was a positive relationship between plant size and relative growth rate (or survival). The slope of yield-density (Y-D) relationships at four densities ranged from -0.060 to -0.137. The study suggests that density can strongly affect the survival and growth of this alga. The density-dependent survival and growth patterns, however, were not strictly consistent with those of terrestrial plants.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.237-245
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• 2006

Changes of the biomass, net primary productivity and P/B ratio during abandoned field succession after shifting cultivation were investigated in Pyoungchang, Gangwon-Do, Korea. Aboveground standing biomass of herb species showed the maximum value (3.8 ton/ha) in the 5 year old-field, and decreased thereafter. Litter dry weight was depicted as a parabola form showing the gradual increment during the first 50 years and slight decrease thereafter. Basal area tended to increase logarithmically during abandoned field succession. Tree density showed the gradual increment during the first 15 years and decreased thereafter by the self-thinning process. In the later successional stage (80 years old-field), the shoot density distribution of the tree species by DBH class showed the reverse J shaped curve and Quercus mongolica dominated. Total standing biomass increased slowly in the earlier successional stages and later successional stages, and increased rapidly during the mid-successional stages ($10{\sim}50$ years old-field). Total standing biomass in the 5, 10, 20, 50 and 80 years old-fields were estimated 5, 14, 75, 251 and 373 ton/ha, respectively. Annual net primary productivity were depicted as a parabola form showing the gradual increment during the first 35 years and declined thereafter. The increment rates of the annual net primary productivity in the earlier successional stages showed the higher value than mid-successional stages. The annual net primary productivities in the 5, 10, 20, 35, 50 and 80 years old-field were estimated 8.6, 9.3, 12.9, 15.1, 13.7 and 3.6 ton/ha/yr, respectively. The estimated P/B ratio tended to decrease exponentially during abandoned field succession. The estimated P/B ratio in the 5, 10, 20, 50 and 80 years old-field were 0.60, 0.39, 0.19, 0.06 and 0.01, respectively. These results were fairly in accordance with the bioenergetics model during the forest succession projected by Odum(1969).

• Journal of Korea Entertainment Industry Association
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• v.15 no.2
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• pp.35-46
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• 2021

The purpose of this research is to analyze Soon Chul Jung's children's songs, who is one of the four great children's songwriters in Korea along with Geuk Young Yoon, Nan Pa Hong and Tae Jun Park. Soon Chul Jung has contributed by actively participate into children's movement at Japanese colonial period through writing self-composed children's songs. Since children's songs are made for the age group without the sense of sound, children's songs necessitate 'easy to sing-along' melody writing process. Like so, when writing the melody that are easy to be sang along, utilization of development technique using a unit called motive can be the potent way. This method has an advantage of being sang more with ease if actively implemented, and can be done by utilizing the smallest unit of the melody called motive, especially by lightly transform and repeat the unit, consequently structuring the song altogether. To investigate and analyze this motive-based development technique of Soon Chul Jung's songs, 38 out of 40 written songs considered eligible for the research were confirmed and chosen from 'Soon Chul Jung's bibliography and choreography' and each songs were analyzed based on 17 different development techniques which were standardized in the textbook 'Melody in Songwriting' adopted as a textbook of the Berklee college of Music, and also compared these song-writing pipelines with other great songwriters' representatives mentioned above. As a result, it was almost linear that the song's pitch variation in combination with thinning or extension were used frequently and repeatedly, otherwise implicating melody duplication for more than 2 bars and motive repetition were not in his favor, while these methods were often used when writing children's songs. This finding could be viewed as a character of his songwriting.