• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.28 no.5
• /
• pp.503-516
• /
• 1995

Macrobenthic community was studied in Deukryang Bay, southwestern coast of Korea, in November 1991 and Januavy 1992. Hacrobenthic fauna consisted of 118 species with 20,767 individuals. The number of species and occurrence frequency of the major groups were as follows: 52 polychaetes species $(44.1\%)$, 45 crustaceans species $(38,1\%)$, 14 mollusks species $(11.9\%)$ and 7 other group species $(5.9\%)$. The mean density was $1432.2ind/m^2$. The density of major groups showed that mollusks was 920.4$(ind./m^2)$, polyrhaetes 275.8$(ind./m^2)$, and crustaceans 219.6$(ind./m^2)$. The dominant species were Musculista senhousia (Bivalvia), Eteone longa (Polychaeta), Nippopisella nagatai (Amphipoda) with density, 632.8$ind./m^2$, 37.8$ind./m^2$, and 35.3$ind./m^2$, respectively. This area could be divided into four areas by the cluster analysis based on the species composition.

• Journal of Korean Society of Forest Science
• /
• v.6 no.1
• /
• pp.37-42
• /
• 1967

This experiment was carried out to study the peeling effect affecting to the natural seasoning by the treatments such as complete peeling, outer bark peeling (attached inner bark) and non peeling for the logs felled in summer and winter season in the stand of about 40 years old pitch pine, located in Kwangyang College Forest, Chollanam-do, Korea. According to the results this study may be concluded as followings. 1. Although the complete peeled logs are seasoned rapidly as compared with the outer barked and non peeled logs but they are more developed seasonal checking. 2. As to the drying effects of the logs felled in summer season, the difference between complete peeled and outer barked or non peeled logs are recognized. Whereas, the difference between outer barked and non peeled logs was not recognized. 3. As to the drying effects of the test logs felled in winter season the difference between complete peeled and outer barked logs were not shown, whereas, the difference between complete peeled or outer barked, and non peeled logs was significantly recognized. Accordingly it is considered that the drying effect of outer barked logs is same with those of complete peeled logs. 4. In this experiment it is expected that the complete peeled logs of summer season felling, and complete peeled or outer barked logs of winter season felling were attained equilibrium moisture contents within four months.

• Journal of the Korean GEO-environmental Society
• /
• v.16 no.6
• /
• pp.23-30
• /
• 2015

This study analyzed degree of disturbance, using specimens by laboratory test with large block specimens and piston samplers collected from the Korea's two typical soft ground districts: South coast Gwangyang and Yangsan. To assess the characteristics of compression index of laboratory test incurred by disturbance, the compression index of laboratory test was compared with the back analysis compression index resulting from the analysis of the measured settlement. The analysis of specimen disturbance of the laboratory test results with the piston specimens of the two districts found that the qualities of most specimens were poor and the settlement predicted by the laboratory test compression index was underestimated. The analysis of test material taken from nearby areas proved that the disturbance degrees of large block specimens were lower than that of the piston specimens. The hyperbolic method, Hoshino method, Asaoka method, and ${\sqrt{S}}$ method, all of which are predictive methods using measured settlement, were employed to reach a conclusion that reliabilities of each predictive method except predictive material of a few points were the same. To compensate the disturbance effects on compression index of the piston specimens, we suggested a new modification formula that estimates compression index of piston specimens, using Schmertmann's corrected compression index, and back analysis compression index from the analysis of predictive settlement.

• Journal of Korean Society of Forest Science
• /
• v.90 no.6
• /
• pp.673-682
• /
• 2001

The objective of this study was to monitor vegetation development process after timber harvesting at (Mt.) Baekwoonsan Seoul National University Forests, Korea. Two monitoring plots were established in 1994 and woody plant were monitored from 1994 to 1999. Vegetation development pattern during last six years(1994-1999) after timber harvesting were as follows; Styrax obassia, Styrax japonica and Lindera erythrocarpa as of the existing tree were competitive species in the first year after clearcut, and Styrax japonica and Lindera erythrocarpa as of sprout tree) and Aralia elata as of seedling were dominant species in the sixth years after clearcut. Species diversity indices of harvested forest interior was decreased at the southwestern slope and increased at the northeastern slope. According to DBH distribution pattern, No. of individuals of Lindera erythrocarpa and Aralia elata showed vigorous growth in the sub-canopy layer and then Styrax japonica, Quercus serrata, Maackia amurensis, Lespedeza maximowixzii, Lindera obtusiloba, Staphylea bumalda, Clero-dendrum trichotomum, Weigela subsessilis, in order showed good growth in the sixth year after clearcut. Lindera erythrocarpa with a reversed J-shaped curve pattern by DBH class will be increased while Aralia elata with a J-shaped curve pattern will be decreased.

• FLOWER RESEARCH JOURNAL
• /
• v.17 no.2
• /
• pp.81-87
• /
• 2009

This study was conducted to examine the characteristics of flowering and fruiting in Nelumbo pentapetala 'Yellow Bird'. Lotus rhizomes were planted in pot (70 cm in length and 71 cm in width) on April 18, 2008, and grown under rain shelter condition at a private farm in Muan-gun, Jeonnam. Ninety percent of the lotus plants were bloomed as two flowers per a plant, and the others were one flower. The first flowers were bloomed in the middle or late July, and the second flowers in the early August. Flower stalks were formed between eighth and tenth internodes in the main rhizome. Nelumbo pentapetala 'Yellow Bird' had light yellow flowers, 12 cm in length and 13 cm in width. Lotus plants of 21.4% were not bloomed, resulting from the insufficient securing of internodes in the main rhizome and the blind. We, therefore, concluded that Nelumbo pentapetala 'Yellow Bird' as a ornamental plant should be grown up to 8 in the node number of main rhizome until mid-July.

• Journal of Korea Port Economic Association
• /
• v.34 no.3
• /
• pp.133-158
• /
• 2018

The role and ratio of national vessels in the global container shipping market have reduced significantly due to the bankruptcy of Hanjin Shipping in early 2017. All import-export companies, as well as container ports in Korea, are facing a crisis. The Trump's tariff and trade battles have had a negative impact on the increase in the North American cargo. However, Chinese and Japanese container shipping companies, which merged with domestic container shipping companies, and mega carriers such as Maersk and CMA CGM have benefited from the decline in shipping supplies due to the collapse of Hanjin Shipping, the world's 10th largest container carrier in Korea. The import/export freight trade in Korea is witnessing the increasing stronghold of foreign carriers. This scenario is expected to weaken Korea's negotiation powers with overseas shipping companies in domestic ports, such as Busan and Kwangyang, thereby making it more challenging to attract shipping carriers. This study compares the global container-shipping network in 2007 and 2017 by combining the network topology of the social network analysis and the economics of the liner shipping connectivity index (LSCI) and the container port connectivity index (CPCI) analysis. The findings of this study are that the role of the ports across the world can be identified, and CPCI has a high correlation with the centrality index and freight volume data. These findings can contribute toward the utilization of the meaning of the necessary centrality index without an additional centrality analysis. This study can be applied not only to the call strategy of container carriers but also to the alliance and development strategy of Korean ports.

• Journal of Korea Port Economic Association
• /
• v.34 no.4
• /
• pp.39-52
• /
• 2018

The Seosan-Daesan Port is a representative trade port in Chungnam, and has the sixth largest total cargo throughput and the third largest oil cargo throughput in Korea. However, research on this port's development is lacking relative to that for Busan Port, Incheon Port, and Gwangyang Port, and no study exists that suggests the direction of the development strategy for Seosan-Daesan Port. This study discusses the future role of Seosan-Daesan Port in preparation for a rapidly changing future and the development strategy that should be established. Using the AHP, a development strategy is provided for Seosan-Daesan Port from short/mid-term and long-term viewpoints for three aspects: operation activation, infrastructure construction, and policy support. Operation activation is chosen as the most significant factor from a short/mid-term viewpoint, whereas infrastructure construction is recognized as important from a long-term viewpoint. Specifically, from a short/mid-term viewpoint, sustainable container cargo attraction, multipurpose dock construction, management pier construction, and opening of international passenger ferry lines are important factors while from the long-term viewpoint, hinterland construction, petrochemical industry cluster construction, automobile industry cluster construction, and management improvement system are important. Establishing action plans for each strategy and a cooperative network for sharing goals and strengthening cooperation is necessary.

• Journal of Korea Port Economic Association
• /
• v.32 no.1
• /
• pp.135-149
• /
• 2016

This study analyzes the concentration ratios (CR) and the shift effect in the system of Korean container ports that concern the export and import of container cargos, especially from/to 5 overseas origin/destination (O/D) regions, using the Hirshmann-Herfindahl Index (HHI) and the Shift-Share Method. The results shows that the CR has decreased during the last 20 years, from 0.86 to 0.44, mainly because cargos from/to the Far-East/South-East Asian regions have become more dispersed to several domestic container ports, especially from the Port of Busan. This study also indicates that there has been little change in the CR for all cargos, like the value of -0.3%, in the last 5 years. However the change in CRs for the cargos from/to the North America and Europe is positive, with the value of 7.6% and 6.6%, respectively. It can be inferred that the future development of medium- and small-sized container ports in Korea is not very likely. The study also suggests that the CR and the shift effect of the Korean container ports for the cargos by the domestic O/D regions should be analyzed in the future to suggest policy implications in great detail.

• Journal of Korea Port Economic Association
• /
• v.32 no.1
• /
• pp.97-122
• /
• 2016

Incheon port attained two million TEU of container throughput between 2013 and 2014 as a third port in domestic container throughput. It opened a new port in Song-do, Incheon in June 2015 to prepare for the continuing increase in container throughput.Therefore, it has provided the platform for being the major container port domestically and internationally. As the role of the new port increases, the role and direction of the Incheon port liner service network attracts attention. This study analyzes the centrality of the Incheon port liner service network by using SNA (Social Network Analysis), which was introduced in the maritime economics area recently, focusing on the Incheon port liner service network. We recognize the degree centrality, closeness centrality, and betweenness centrality of each port and its effect on the Incheon port liner service network. The study showed that for Incheon port, the centrality of the Busan port in Korea, and the Hong Kong port, is high outside the country. This helps us determine that the hub of the Incheon port is neither Shanghai nor Singapore, which ranks first and second, respectively, on container throughput. It is also helps us to know that eastern China's ports have not played a role of the hub of the Incheon port until now because of the relatively low centrality of eastern China's ports.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.6
• /
• pp.1124-1129
• /
• 2011

The importance of environment-friendly agriculture is being magnified as a new growth engine industry in pursuit of low carbon, green growth policies. In order to provide technical supports for pushing ahead with the environment-friendly agriculture policies, we estimated the effects of customized fertilization on growth and yield of rice and fertilizer reduction compared to conventional fertilization and single-element fertilization. In rice plant growth and rice yield, no statistically significant difference between the three fertilization treatments was observed. In contrast, customized fertilization showed high disaster resistance reducing the damage caused by rice lodging during a typhoon. The average N application in farms showing high rice lodging amounted to $135kg\;N\;ha^{-1}$ while $135-138kg\;N\;ha^{-1}$ was known as the critical range of rice lodging in Korea. The fertilizer reduction rate of customized fertilization compared to conventional fertilization of investigated farms was on average 22.5%. We estimated the short-term effects of customized fertilization in the first year after application. In future, there is need for continuous examination of rice growth and soil environment change due to successive application of customized fertilizer.