• Ocean and Polar Research
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• v.34 no.4
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• pp.403-411
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• 2012

Among others, a question that has long been unanswered is why the seasonal variation of volume transport is larger in the Soya and Korea/Tsushima Straits than in the Tsugaru Strait. An attempt is made to answer this question in terms of the island rule with friction being taken into account. The problem is idealized as a simple model. The model results indicate that volume transport through a channel is determined not only by the circulation created around the adjacent island but also by those created around the neighboring islands farther away. The latter is due to the presence of bottom friction in the channels. The volume transports through the Korea/Tsushima, Tsugaru and Soya Straits estimated from the model using observed wind data show the general pattern of observed seasonality, although they contain large errors associated with the uncertain frictional parameter employed in the model. The model indicates that the observed seasonality arises essentially from the fact that wind stress curl changes its sign, from negative in the summer to positive in winter, following a large fluctuation of zero-stress curl latitude east of Hokkaido.

• Animal Systematics, Evolution and Diversity
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• v.37 no.3
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• pp.205-211
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• 2021

This study investigates the morphological and skull characteristics of the Siberian weasel Mustela sibirica quelpartis from the Jeju Island, South Korea. A total of 26 roadkill specimens (22 males and 4 females) were collected from October 2012 to April 2016. All collected specimens were examined for morphological characteristics, but only 19 specimens (16 males and 3 females) were in a good enough condition to process for skull measurements. This study showed no significant differences in ear length between male and female (p>0.05), and significant differences were found in head-body length, tail length (TL), and hind-food length (p<0.05). Both the male and female of M. s. quelpartis were larger in its external characteristics except for TL than M. s. coreanus living in the mainland of South Korea. M. s. quelpartis males have a smaller skull size than their female counterparts. In general, both male and female M. s. quelpartis showed external characteristics in line with the Island Rule. The findings of this study are important in order to shed more light on the evolutionary mechanism of small mammals living on the Jeju Island.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.3
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• pp.226-232
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• 2003

In this paper, design rule of power island is studied. Power island have a defect that increase transfer noise when each power bus structure is resonant. So, in this paper, resonances are suppressed for various noise source positions and in order to improve noise characteristics, it is suggested EGI in order to improve noise characteristic. At the simulation result, the least resonance is showed for various noise source position and transfer impedance with power bus resonance is reduced about 11 $\Omega$ by EGI.

• The Korean Journal of Ecology
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• v.5 no.4
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• pp.211-221
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• 1982

Tracheophyta produced in this island consisted of 77 families, 180 genera, 214 species, 28 varieties and 1 forma, lauriligonosa of which comprised species and varieties. As in the case of neightboring Nowhado, Bogildo and Choungsando islands, this island was also a supply source of fuel woods consumed mainly in Mokpo and Wando cities during the period of Japanese rule and for about a decade after the liberation of Korea in 1945. Consequently it was once almost deforested, but its restorative proces has successfully taken place for about 25 years and now Pinus thunbergii is distributed dominantly all over the mountains and plains of the island. The forest of the Seonangdang (shrine of a tutelary diety) at Bijari and the windbreak forests at Minari, Maengseonri and Soan High School compound were formed with the old trees of laurilignosa, such as Machilus thunbergii, Machilus japonica, Castanopsis cuspidata and Camellia japonica. These shelter belts were relatively well preserved.

• Journal of Korea Water Resources Association
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• v.51 no.12
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• pp.1261-1271
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• 2018

This study evaluates the applicability of the classification rule of hydrological soil group proposed by Lee et al. (2018) with its application to three river basins (Jungmuncheon, Cheonmicheon, and Hancheon) in Jeju Island. The CN values are estimated as results of this application to these three basins, which is then compared with those estimated by applying the conventional three methods. Additionally, previous studies related with the classification of soil groups of Jesu Island, such as the infiltration and rainfall-runoff analysis, are reviewed to evaluate how the resulting hydrological soil groups vary depending on the adopted classification method.. Summarizing the results is as follows. (1) Comparison result of the hydrological soil groups of Jeju Island with respect to the classification method shows that the soil group B is dominant in the application of Lee et al. (2018). However, it is hydrological soil groups C and D in the application of Hu and Jung (1987), hydrological soil groups A and C in the application of Jung et al. (1995), and hydrological soil group D in the application of RDA (2007). (2) In all the applications of Lee et al. (2018) to three selected river basins in Jeju Island, the CN valuse are found to be smaller than those by other conventional three methods.. Lastly, (3) The evaluation results of previous studies related with the classification of hydrological soil groups analysis in Jeju Island shows that the CN value in the Jeju Island may be smaller than those estimated by conventional three methods, also the initial loss higher than 0.2S.

• Spatial Information Research
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• v.21 no.1
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• pp.63-73
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• 2013

Geographic features are reflected in satellite images, which contain characteristic elements. Information on changes can be obtained through a comparison of images taken at different times. If multi-temporal images can be classified through the use of an unsupervised method, this is likely to improve the accuracy of image classification and contribute to various applications. A rule-based image classification algorithm for automatic processing without human involvement has been developed, but it must be verified that its results are not affected by imperfect elements. In this study, Landsat images of Jeju Island were used to carry out a rule-based image classification. The application results were examined for complex cases, including the presence of clouds in the images, different photographed times, and the type of target area, such as city, mountain, or field. The presence of clouds did not affect calculations, and appropriate classification rules were applied, depending on the different photographed times. The expansion of the urban areas of Jeju and the increase of facilities such as vinyl greenhouses in Seoguipo were identified. Furthermore, space information changes and accurate classifications for Jeju Island were obtained. With the goal of performing high-quality unsupervised classifications, measures to generalize and improve the methods employed were searched for. The findings of this study could be used in time-series analyses of images for various applications, including urban development and environmental change monitoring.

• Journal of architectural history
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• v.8 no.4 s.21
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• pp.81-94
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• 1999

The purpose of this study is to interpret a house as material into culture. Main method is an ethnographic interview with dwellers as a part of a participant observation, a kind qualitative study. Significantly two different types of folk housing are discovered in East and West areas of the Cheju Island. In the East, kitchen itself forms a separated building, Jeongji-gori, whereas in the West, kitchen is within a main building, An-gori. Different type of kitchen is formed by the different family system. While independent family system of son and father selects a separate kitchen building as a general rule of Cheju Island, an extended family system between father and son selects same kitchen, Jeongji-gori, in the east area. Natural environment of infertile soil of east area makes family work together and eat together. Inner space of the kitchen building is utilized not only in cooking but also in eating, working, and sleeping. In order to explain folk house type, a 'culture area' concept is suggested. The interrelated 'cultural type' of architecture behind a physical surface 'type' is suggested as a new typology.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.575-581
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• 2018

The relationship between the body size of species and the environment has been an active research subject for many years. Until recently, studies had focused on the relationship between the body size and environment based on the ecogeographic rule for various animal groups. In this study, we examined the relationship between body size of Hyla japonica and the habitat environment in Jeju island located at the southernmost part of the Korean peninsula. We collected H. japonica from three breeding sites, Cheonji, Bonggae, and Aewol, and measured SVL, BW, and HW of the species. We also measured the altitude, longitude, latitude, annual mean temperature, and annual mean precipitation of each site to analyze the relationship between the body size and the habitat environment. The analysis results showed that there was the clear difference of the body size according to the habitat and the body size in Aewol was significantly bigger than others, while the body size in Cheonji was the smallest. The altitude was the most important environmental variable and showed a positive correlation with body size. The body size of H. japonica increased as the altitude increased, and this results were consistent with Bergmann's rule, one of the biological laws related to body size. In conclusion, the environment could affect the body size of H. japonica, and the body size has a certain direction according to the environment.

• The Korean Journal of Ecology
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• v.4 no.3_4
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• pp.68-79
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• 1981

We discovered following on our surveys to the island six times in May, August (1978), in April, May, June, July (1979). There are 73 families, 158 genera, 189 species, 31 varieties over Tracheophyta Fuller & Tippo. Till early or middle age of Lee Dynasty, the island's dominant plants was evergreen broad-leaved trees, mainly consisted with Camellia japonica L. and Castanopsis cuspidata Schot, var. sieboldii Nakai but due to the population growth and increased exiles constant ground burnt off fr cultivation, the number of evergreen broad-leaved trees was decreased and that of P. densiflora S. et Z. replaced position. That is to say, the island was dominated by the flora of the subtropical zone era, but it has been complicated by flora of the temperate zone whose reproductivity is more vivid, in modern era. Recently Pinus thunbergiana Franco, Robinia pseudo-acasasia L. Amoroha fructicasia L. invaded and reserved inthe island. During a decade of the end of Japanes rule and after liberation about all of Pinus densiflora S. et Z. were cut downed, and after that, under the Forest Bureau, there have being sucessed to Pinus thunbergiana France. Camellia japonica L. other 20 species of evergreen broad-leaved trees are distributed in Island Wi, a tutelary shrine of Dae Ri, a mountain at the back of a village of Chi Do Ri and a mountain at the back of Jin Ri administrative office of a township. The special plants of the island are 1) state of Lycoris aurea Herb which of foun in a ridge between fields and forest around Jin Ri and 2) stock of Cmbidium virescens Lindly bloomed under the Pinus densiflora forest of Keun Tan Chi Do.

• Journal of Ecology and Environment
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• v.30 no.3
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• pp.251-255
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• 2007

Self-thinning was measured in Salix communities on Bam Island in Seoul at various age stages. $D^2H$ was used to estimate tree biomass, where D is stem diameter at breast height or 10 cm height for plants with height <1.5 m, and H is height. A log-log plot of density versus $D^2H$ and correlation analysis indicated a significant relationship between density and biomass with equation 'log $D^2H$ = -1.27 log N + 7.06'. This indicates that self-thinning affects biomass in the Salix community with -1.27 as the thinning coefficient. If we assume a thinning exponent -3/2, then the allometric coefficient of the equation, log w = a log $D^2H$ + b, is 1.18. This is much higher than that for any other species studied in Korea. There were statistically significant relationships between age and density and between age and basal area and these relationships suggest guidelines for transplantation of willows and for the assessment of Salix community restoration projects in riverine wetlands based on standard density, basal area, and age. The results of this study may also increase understanding of succession processes in Salix community restoration in riverine wetlands.