• 한국해양학회지
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• v.28 no.3
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• pp.192-201
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• 1993

To reduce tsunami hazards, it is necessary to develope the methods which can simulate tsunami wave signals of coastal areas. In the present paper, it is attempted t use Sign Method for analyzing and simulating recorded tsunami signals. A tsunami record Y(t) can be represented as the convolution integral of a source evolution function E(t') and a wave propagation function K(t-t') Y(t)=.int. E(t')K(t-t')dt' A source function contains the peculiarities of a tsunami generator. A wave function is a kind of transfer function which contains the characteristics of a wave propagation path. The source functions and the wave function and the wave functions of 9 Korean coast points and 6 Japan coast points are estimated, and the tsunami wave signals are simulated by the convolution integrals of the source functions and the wave functions. According to the results of analysis, the Sign Method is an effective method for simulating tsunami wave signals of Korean coast points which are located far from tsunami source areas. Furthermore, if the source function of a neighboring point ad the wave function of an another tsunami are given, unrecorded tsunami wave also can be estimated.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.353-358
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• 2018

Solidago virgaurea subsp. gigantea is native to Ulleung-do, island in East Sea, and cultivated as a vegetable in Korea. Rust fungus on this plant was first reported as Coleosporium asterum in 2014. Recent studies on Solidago-Coleosporium association mainly based on North American materials suggested that the Korean isolates of C. asterum on S. virgaurea subsp. gigantea reported in Korea might be placed in the C. solidaginis clade. Accordingly, to confirm this suggestion, three additional Korean samples were morphologically and molecularly studied and identified as C. solidaginis in current species concept. Three specimens on S. altissima (syn. S. canadensis) from China and Japan were previously determined to be phylogenetically differentiated from C. solidaginis, hinting at a cryptic species. Therefore, this is the first confirmed report on the presence of C. solidaginis on Solidago spp. in Asia.

• Korean journal of applied entomology
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• v.20 no.1 s.46
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• pp.51-58
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• 1981

Hitherto 44 species belonging to 19 families of spiders have been reported at Ulreung-do on the East Sea. Korea. The authors have investigated spider fauna, through out the Ulreung-do, during July 25, August 3. 1975 and July 30, August 7, 1980. The foundings were as followings. 1) In this report, 132 species of 74 genera, including 3 undetermined species, belonging to 25 families of spiders are tabulated by the aid of published data and collections of the authors. Eighty six species are added to the fauna, of which 2 species are new to Korea. as follows; Porrhomma montanum Jackson. 1918, Clubiona neglecta O.P. Cambridge, 1862. The spider fauna of Ulreung-do includes 18 nothern species $(14.0\%)$, 8 southern species $(6.2\%)$. 7 cosmopolitan species $(5.4\%)$ and 84 Palaearctic temperate species $(65.1\%)$. The predominant species are Araneids. Thridiids, especially Cyclosa japonica Boes. et Str. are found in large numbers all over this island. Linyphiids and Lycosids are relatively few in number. 3) The common species to comparative area and foreign countries are as follows; Ulreung-do/Jookbyeon...76 species$(43.3\%)$ Ulreung-do/Jeju-do...95 species$(40.6\%)$ Ulreung-do/Heuksan do...61 species$(35.7\%)$ Ulreung-do/Deogjeog-do...51 species$(31.7\%)$ Ulreung-do/Tsushima Isl....71 species$(30.3\%)$ Ulreung-do/Japan...112 species$(11.3\%)$ Ulreung-do/main China...59 species $(6.5\%)$ 4) The ecological distribution are as follows; The seashore region...81 species$(62.8\%)$ The evergreens region...73 species$(56.6\%)$ The highiands region...64 species$(49.6\%)$ The valleys region...49 species$(38.0\%)$ The basin region...23 species$(17.8\%)$ 5) The noticeable one of geographical distribution in this island, are as follows; Nesticus quelpartensis Paik et Namkung, 1969, Conoculus simboggulensis Paik, 1971.

• Ocean and Polar Research
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• v.35 no.3
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• pp.259-272
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• 2013

One of the factors influencing the climate around Korea is the oceanic-atmospheric variability in the tropical region between the eastern Indian and the western Pacific Oceans. Lack of knowledge about the air-sea interaction in the tropical Indo-Pacific region continues to make it problematic forecasting the ocean climate in the East Asia. The 'Tropical Indo-Pacific water transport and ecosystem monitoring EXperiment (TIPEX)' is a program for monitoring the ocean circulation variability between Pacific and Indian Oceans and for improving the accuracy of future climate forecasting. The main goal of the TIPEX program is to quantify the climate and ocean circulation change between the Indian and the Pacific Oceans. The contents of the program are 1) to observe the mixing process of different water masses and water transport in the eastern Indian and the western Pacific, 2) to understand the large-scale oceanic-climatic variation including El Nino-Southern Oscillation (ENSO)/Warm Pool/Pacific Decadal Oscillation (PDO)/Indian Ocean Dipole (IOD), and 3) to monitor the biogeochemical processes, material flux, and biological changes due to the climate change. In order to effectively carry out the monitoring program, close international cooperation and the proper co-work sharing of tasks between China, Japan, Indonesia, and India as well as USA is required.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.295-300
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• 2010

Recently, many tsunamis triggered by impulsive undersea ground motions occurred in subduction zones around the Pacific Ocean area including the East Sea surrounded by Korea, Japan and Russia. The wave height of a tsunami may be in the order of several meters, while the wavelength can be up to 1,000 km in the ocean, where the average water depth is about 4 km. A tsunami could cause a severe coastal flooding and property damage not only at neighboring countries but also at distant countries. A fundamental and economic way to mitigate unusual tsunami attacks is to construct tsunami hazard maps along coastal areas vulnerable to tsunami flooding. These maps should be developed based on the historical tsunami events and projected scenarios. The map could be used to make evacuation plans in the event of a real tsunami assault.

• Economic and Environmental Geology
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• v.38 no.3 s.172
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• pp.299-304
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• 2005

Geoid undulation and gravity anomaly were calculated from GRACE satellite data on the eastern Asia including Korean peninsula. Geoid undulation varies from -60m in the China to 60m toward the Pacific Ocean across the Korean Peninsula. Calculated gravity anomalies are in the range of -60 and 60 mgal except the subduction zone showing -100 mgal. High positive values are observed at Mt. Baekdu, Kaema highland and Taebaek mountains, and low values at Ulleung, Japan and Yamato basins in the East sea. We removed regional components below the spherical harmonic degree of 10 from gravity anomaly to get the residual anomaly for crust components. Residual gravity anomaly shows high anomalies at the northern mountainous area and Kyungsang basin in the Korean Peninsula. And low anomalies appears at the western Korea bay basin, Kunsan basin, Cheju basin, and Ulleung basin in the marine. Anomalies separated by the spherical harmonic degree as well as the residual anomalies are useful for the study of large crustal structure about geologic scale and depth distribution and for the survey of natural resources.

• The Korean Journal of Zoology
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• v.15 no.2
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• pp.87-91
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• 1972

For the geographical distribution of Primno macropa it was distributed over all stations investigated, except surface tow in East China Sea, through all seasons. It is believed that this species is most cosmopolitan species in the western North Pacific. Veritical distributional range of P. macropa indicates at depths from surface to more than 1,500m and most deeper recored for the vertical occurrence was obtained from depth of 1,650-2,220m in Station 229 $(34^\\circ 44.3'N, 140^\\circ 04.4'E)$, off Nojima-Zaki, Central Japan. For the vertical distributional and migrational pattern it is a typical diurnal migrant in the western North Pacific; at depths from 100m to 500m at night and 400m to 700m at day in Oyashio population, and from surface to 200m at night and from 100m to 300m at day in Kuroshio population. In Kuroshio area, the population of P. macropa was distributed in somewhat shallower layers than in Oyashio area and it is suggested that the populations is different in region and season according to their stages consisting the population.

• Journal of the Korean association of regional geographers
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• v.19 no.2
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• pp.282-300
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• 2013

This study regards that a cause of intensifying sovereignty disputes between Korea and Japan over the Dokdo island has resulted from the fallacy of Dokdo's development policy directly related to exertion and consolidation of Korean government's sovereignty on Dokdo, which has been under Korea's effective control since 1953. From this internal view, this study critically reviews the Korean government's development policy for Dokdo from the 1950s to the end of July 2012 and suggests an ideal alternative for future development of Dokdo on the basis of the discussion of the problems of Dokdo's development policy and its different future development directions proposed in Korean society. The Korean government implemented quite passively the development policy for the inhabited island which is required for the consolidation of sovereignty over Dokdo not to hinder the friendly diplomatic relationship between Korea and Japan. Dokdo is currently not acknowledged as the Korea's Dokdo island in international society, but mostly called Liancourt Rocks. It may be due to the fact that Korea did not positively develop Dokdo as a valuable island which a number of Koreans can inhabit. Consequently this paper proposes 'Dokdo eco-village' as an alternative development plan from the perspective of sustainable development which the UN has adopted. It is a small scale village that contains economic function of eco-friendly fishing, eco-tourism and East Sea research. The hope is that Dokdo eco-village draft plan will be a clue to the discussion and establishment of new Dokdo's development policy to strengthen the Korea's sovereignty and effective control over Dokdo in the future.

• Journal of the Korean Magnetics Society
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• v.21 no.3
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• pp.116-119
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• 2011

A Chinese shipping boat collided with two Japanese coast guard boats in waters near the disputed Senkaku islands (known as Diaoyudao in China) in the East China Sea on September 7th last year. The boat was held and captain was arrested by Japanese Government. The incident soon turned into a big political and economic conflict between the two countries. Japan's intention was to show her tight control over Senkaku, whereas China's intention was to make it a disputed territory in the eyes of international politics. While the conflict was going on, a top-rank bilateral talk between the two countries was suspended, boycott of Japanese goods was suggested, numerous rallies were held in both countries. This situation lasted for several months until China used an extreme card of "Cutting Supply of Rare Earth to Japan". Under this pressure, Japan instantly released the captain and closed the case. Over this incident, public noticed the importance of rare earth and its impact on the global economy. Since then, the policy of Chinese Government for the rare earth has created more confusion and turmoil in the global market. The purpose of this article is to overview the price rally and future of the rare earth.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.36 no.2
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• pp.80-86
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• 2024

Large-scale earthquakes are occurring globally, especially in the South Asian crust, which is experiencing a state of tension in the aftermath of the 2011 East Japan Earthquake. Uncertainty and fear regarding the possibility of further seismic activity in the near future have been on the rise in the region. The National Disaster Management Research Institute has previously studied and analyzed the overflow characteristics of a tsunami and the rate of flood forecasting through tsunami numerical simulations of the East Sea of South Korea. However, there is currently a significant lack of research on the Southern Coast tsunamis compared to the East Coast. On the Southern Coast, the tidal difference is between 1~4 m, and the impact of the tides is hard to ignore. Therefore, it is necessary to analyze the impact of the tide propagation characteristics on the tsunami. Occurrence regions that may cradle tsunamis that affect the southern coast region are the Ryukyu Island and Nankai Trough, which are active seafloor fault zones. The Southern Coast has not experienced direct damage from tsunamis before, but since the possibility is always present, further research is required to prepare precautionary measures in the face of a potential event. Therefore, this study numerically simulated a hypothetical tsunami scenario that could impact the southern coast of South Korea. In addition, the tidal wave propagation characteristics that emerge at the shore due to tide and tsunami interactions will be analyzed. This study will be used to prepare for tsunamis that might occur on the southern coast through tsunami hazard and risk analysis.