• Journal of the Korean GEO-environmental Society
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• v.15 no.2
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• pp.27-36
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• 2014

Due to the latitudinal location of Korea, the seasonally frozen ground has been focused on as research topics such as the frost heaving under the asphalt road rather than the permafrost ground. However, the recent construction of the second Korean Antarctic research station, the Jangbogo station and the participation on the development of the natural gas pipeline in Russia arouse the research interests on the behavior of the permafrost ground. At the design process of the geotechnical structures on the permafrost ground, the evaluation of the creep characteristics of the frozen soil is very crucial. Since the domestic specification on the frozen soil testing does not exist currently, it is necessary to evaluate the creep characteristics of frozen soils systematically with regard to the affecting factors. Therefore, the creep characteristics of the frozen specimens of dense Jumoonjin sand were evaluated under various loads at -5 and $-10^{\circ}C$. Based on the test results, as the load became close to the strength and the temperature became lower, the duration of the secondary creep became shorter and more distinct tertiary creep responses were observed.

• Korean Journal of Plant Taxonomy
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• v.43 no.4
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• pp.300-311
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• 2013

Subalpine species, Sorbus pohuashanensis in the Korean peninsula, which is assumed to be evolved from hybridization between S. commixta and an unknown species based on the flavonoids data. Morphometric analysis was conducted on the basis of 19 leaf and flower (or fruit) characters. A total of 721 samples in 13 populations of Sorbus pohuashanensis and S. commixta from Korea and additional specimens of S. commixta, S. pohuashanensis, and S. wilsoniana from Japan and China were examined to reveal the hybridization patterns and morphological differences. We found a preliminary evidence where Korean mountain rowan is more related to a Chinese inland taxon, S. wilsoniana, rather than Northeastern Chinese S. pohuashanensis in terms of flavonoids. The current morphological structure of the Korean mountaion rowan, however, which is more similar to S. commixta, was neither associated with that of S. wilsoniana nor that of S. pohuashanensis. This indicates that this morphological variation represents an intermediate of S. commixta and S. wilsoniana via a more ancient hybridization event in terms of qualitative characters, such as stipules, buds, and carpels. These morphometric differences together with other distinguishing characteristics suggest that the Korean mountain rowan should be considered as a conspecific species of S. commixta, although this demonstration of hybridization with the current phenetic species concept contradicts longstanding historical species concept.

• Journal of Korea Port Economic Association
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• v.32 no.4
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• pp.109-126
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• 2016

This study investigates the initiatives of Gangwon sea routes based on precedent studies on the North Pole route to suggest a multi-modal buildup of transport logistics network of Gangwon harbors for the strengthening of logistics efficiency in the Korean Peninsula. The findings were: First, the government should expand railway infrastructure in Gangwon. Second, harbors in Gangwon should each have one speciality to strengthen connection with other harbors by using railway oriented background transportation network. Third, the government should develop industries of EFEZ(East coast Free Economic Zone) in the East Sea Coast in Gangwon to connect resources from the North Pole Sea. Fourth, the government should invite the base of Araon Ho's polar research vessel to play the role of the North Pole Sea route in the near future. Fifth, the government should strengthen the role of the Samcheock LNG base under construction. SIxth, environment-friendly transportation technology should be introduced to reduce carbon emission as much as possible. Lastly, an optimum North Pole logistics route should be developed to connect the Metropolitan area(Metropolitan Economic Zone), Gangwon roads and railway, Gangwon habor, Trans-Siberian Railway and thw North Pole route, and Europe, to strengthen national foreign trade power in the near future.

• Korean Journal of Plant Taxonomy
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• v.34 no.3
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• pp.221-244
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• 2004

Prunus sargentii complex of subgenus Cerasus is an Eastem Asiatic plant group that exhibits a broad range of morphological variation and includes P. takesimensis, P. yedosensis, P. verecunda, and P. sargentii. In this study, a morphological analysis was undertaken to determine whether the observed morphological variation was primarily attributable to morphological discontinuities among the taxa. P. sargentii, which distributed eastem area in Korea, northern area in Japan and far east Russia had umbel like inflorescence and additionally was characterized by sticky bud and leaf twigs, compared with P. serrulata complex. Also, P. verecunda in Korea and Japan was characterized by umbel like inflorescence and presence of hair in leaf, petiole and pedicel, and was treated as a variety of P. sargentii. Evidence obtained from multivariate morphometric analyses indicated that the entity of P. takesimensis formed a cohesive group somewhat distinct from P. sargenti.. Especially, P. takesimensis was characterized by relatively small flowers (26-32mm in diameter) and many flowers [(2)3-5] per umbel inflorescence, compared with P. sargentii (34-48mm and 2(3) per inflorescence) and should be recognized as an independent and endeImic taxon in Korea. Additionally, P. yedosensis, which was known to have umbel inflorescence (short peduncle type) with pubescent style based on the type specimen, was comprised of corymb inflorescence (long peduncle type) as well. The morphological differentiation between these two types of P. yedosensis was not considered sufficient to warrant recognition of specific status because of the putative hybrid origin, no distinctive geographical distribution pattern, and existence of various peduncle length on Island Jeju-do of Korea.