• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.351-373
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• 2019

The cold eddies around the Ulleung Basin in the East Sea were identified from satellite altimeter sea level data using the Winding-Angle method from 1993 to 2015. Among the cold eddies, the Dokdo Cold Eddies (DCEs), which were formed at the first meandering trough of the East Korea Warm Current (EKWC) and were pinched off to the southwest from the eastward flow, were classified and their migration patterns were analyzed. The vertical structures of water temperature, salinity, and flow velocity near the DCE center were also examined using numerical simulation and observation data provided by the Hybrid Coordinate Ocean Model and the National Institute of Fisheries Science, respectively. A total of 112 DCEs were generated for 23 years. Of these, 39 DCEs migrated westward and arrived off the east coast of Korea. The average travel distance was 250.9 km, the average lifespan was 93 days, and the average travel speed was 3.5 cm/s. The other 73 DCEs had moved to the east or had hovered around the generated location until they disappeared. At 50-100 m depth under the DCE, water temperature and salinity (T < $5^{\circ}C$, S < 34.1) were lower than those of ambient water and isotherms made a dome shape. Current faster than 10 cm/s circulates counterclockwise from the surface to 300 m depth at 38 km away from the center of DCE. After the EKWC separates from the coast, it flows eastward and starts to meander near Ulleungdo. The first trough of the meander in the east of Ulleungdo is pushed deep into the southwest and forms a cold eddy (DCE), which is shed from the meander in the south of Ulleungdo. While a DCE moves westward, it circumvents the Ulleung Warm Eddy (UWE) clockwise and follows U shape path toward the east coast of Korea. When the DCE arrives near the coast, the EKWC separates from the coast at the south of DCE and circumvents the DCE. As the DCE near the coast weakens and extinguishes about 30 days later after the arrival, the EKWC flows northward along the coast recovering its original path. The DCE steadily transports heat and salt from the north to the south, which helps to form a cold water region in the southwest of the Ulleung Basin and brings positive vorticity to change the separation latitude and path of the EKWC. Some of the DCEs moving to the west were merged into a coastal cold eddy to form a wide cold water region in the west of Ulleung Basin and to create a elongated anticlockwise circulation, which separated the UWE in the north from the EKWC in the south.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6B
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• pp.731-741
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• 2008

Previous studies on the numerical simulation at the tidal reach of Han River tend to restrict downstream boundary as Jeon-ryu station due to difficulties in gaining cross section data and tidal elevation values at Yu-do. But, in this study, geometries beyond the confluence of Gok-reung stream and Im-jin River are constructed based on the numerical sea map; tidal elevation at the downstream boundary, Yu-do is estimated by harmonic analysis of In-cheon tide gage station so that hydrodynamic and diffusion behavior have been analyzed. The domain ranging from Shin-gok submerged weir to Yu-do is selected (which is 36.8 km in length). RMA-2 and RAM4 developed by Il Won Seo (2008) are applied to simulate flow and diffusion behavior, respectively. Numerical results of flow characteristic are compared with the measured data at Jeon-ryu station. Simulation is carried out from June 23 to 25 in 2006 on the ground that hydrologic data is satisfactory and tidal difference is huge during that period. The result shows that reverse flow occurs 5 times according to the tidal elevation at Yu-do and the maximum reverse flow is observed up to Jang-hang IC, which is 32.9 km in length. Also analysis is focused on the process of generation and disappearance of reverse flow, the distribution of water surface elevation and velocity along the maximum velocity line, and the transport of nonconservative pollutant. Pollutant injected from Gul-po stream spreads widely across the river; however, the size of BOD cloud entering from Gok-reung stream is relatively small because water depth at the mid and left side becomes deeper and maximum velocity occurs along the right bank so that transverse mixing is completed quickly. Finally, mixing characteristic of horizontal salinity distribution is obtained by estimating the salinity input with analytical solution of 1D advection-dispersion equation.

• The Korean Journal of Quaternary Research
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• v.14 no.1
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• pp.7-31
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• 2000

Quaternary Geological and geophysical investigation was performed at the Eurimji reservoir of Jaechon City in order to interprete depositional environment and genesis of lake sediments. For this purpose, echo sounding, bottom sampling and columnar sampling by drilling on board and GPR survey were employed for a proper field investigation. Laboratory tests cover grain size population analysis, pollen analysis and $^{14}C$ datings for the lake sediments. The some parts of lake bottom sediments anthropogenically tubated and filled several times to date, indicating several mounds on the bottom surface which is difficult to explain by bottom current. Majority of natural sediments were accumulated both as rolling and suspended loads during seasonal flooding regime, when flash flow and current flow are relatively strong not only at bridge area of the western part of Eurimji, connected to stream valley, but at the several conduit or sewage system surrounding the lake. Most of uniform suspend sediments are accumulated at the lake center and lower bank area. Some parts of bottom sediments indicate the existence of turbid flow and mudflow probably due to piezometric overflowing from the lake bottom, the existence of which are proved by CM patterns of the lake bottom sediments. The columnar samples of the lake sediments in ER-1 and ER-3-1 boreholes indicate good condition without any human tubation. The grain size character of borehole samples shows poorly sorted population, predominantly composed of fine sand and muds, varying skewness and kurtosis, which indicate multi-processed lake deposits, very similar to lake bottom sediments. Borehole columnar section, echo sounding and GPR survey profilings, as well as processed data, indicate that organic mud layers of Eurimji lake deposits are deeper and thicker towards lower bank area, especially west of profile line-9. In addition the columnar sediments indicate plant coverage of the Eurimji area were divided into two pollen zones. Arboreal pollen ( AP) is predominant in the lower pollen zone, whreas non-aboreal pollen(NAP) is rich in the upper pollen zone. Both of the pollen zones are related to the vegetation coverage frequently found in coniferous and deciduous broad-leaved trees(mixed forest) surrounded by mountains and hilly areas and prevailing by aquatic or aquatic margin under the wet temperate climate. The $^{14}C$ age of the dark gray organic muds, ER1-12 sample, is 950$\pm$40 years B.P. As the sediments are anthropogenetically undisturbed, it is assumed that the reliability of age is high. Three $^{14}C$ ages of the dark gray organic muds, including ER3-1-8, ER3-1-10, ER3-1-11 samples, are 600$\pm$30 years B.P., 650$\pm$30 years B.P., 800$\pm$40 years B.P. in the descending order of stratigraphic columnar section. Based on the interpretation of depositional environments and formation ages, it is proved that Eurimji reservoir were constructed at least 950$\pm$40 years B.P., the calibrated ages of which ranges from 827 years, B.P. to 866 years B.P. Ancient people utilize the natural environment of the stream valley to meet the need of water irrigation for agriculture in the local valley center and old alluvium fan area.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.68-87
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• 1982

In Korea, this is the situation at moment that the total demand of timber in 1972 is more than 5 million cubic meters. On the other hand, however, the available domestic supply of timber at the same year is only about, 1 million cubic meters. A great unbalancing between demand and supply of timber has been prevailing. To solve this hard problem, it has been necessitiated to build up the forest stocks as early as possible with fast grown species such as poplar. Under circumstances, poplar plantations which have been carryed on government and private have reached to large area of 116,603 hectors from 1962 up to date. It has now be come a principal timber resources in this country, and required the basic study on various properties of wood for it's proper utilization, since it has not been made of any systematic study on the properties of Populus grown in Korea. In order to investigate the properties such as anatomical, physical and mechanical properties of nine different species (P. euramericana Guiner I-214. P. euramericana Guiner I-476, P. deltoides Marsh, P. nigra var. italica (Muchk) Koeme, P. alba L.,P. alba $\times$ glandulosa P. maximowiczii Henry, P. koreana Rehder, P. davidiana Dode) of poplar for their proper use and development of new ways of grading processing and quality improving, this study has been made by the Forest Research Institute.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.96-108
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• 1982

Pinus is one of the most important species supplying domestic industrial timbers such as constitutional lumber, pulpwood, and mine props. It occupies nearly 50 percent of the total forest resources in Korea. With above conception, to develop this forest resources and to obtain the basic data on the reasonable and effective utilization of Pinus, this study was carried out. Five species (P. koraiensis S. et Z., P. densiflora S. et Z., P. thunbergii Parlat, P. densiflara far erecta, P. rigida Miller) grown in Kwangnoong experimental forest stand, Chungcheongnam-Do, and Gangwon-Do regions were selected as sample trees. Anatomical, physical, mechanical and chemical properties of them were investigated.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.4
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• pp.67-80
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• 2022

SipWooDo (十牛圖: Painting of Ten Bulls), a Buddhist painting, is a kind of Zen Sect Buddhism painting, which is shown as a mural in many of main halls of Korean Buddhist temples. MokWooDo has been painted since Song Dynasty of China. It paints a cow, a metaphor of mind and a shepherd boy who controls the cow. It comes also with many other types of works such as poetry called GyeSong, HwaWoonSi and etc. That is, it appeared as a pan-cultural phenomenon beyond ideology and nation not limited to Chinese Buddhist ideology of an era. This study, therefore, selects MokWooDo chants that represent Confucianism, Buddhism and Taoism to compare the writing purposes, mind discipline methods and ultimate goals of such chant literatures in order to integrate and comprehend the ideologies of such three schools in the ideologically cultural aspect, which was not fully dealt with in the existing studies. In particular, the study results are: First, the SipWooDo of Buddhist School is classified generally into Bo Myoung's MokWooDo and Kwak Ahm's SimWooDo (尋牛圖: Painting of Searching out a Bull). Zen Sect Buddhism goes toward nirvana through enlightenment. Both MokWooDo and SimWooDo of Buddhist School are the discipline method of JeomSu (漸修: Discipline by Steps). They were made for SuSimJeungDo (修心證道: Enlightenment of Truth by Mind Discipline), which appears different in HwaJe (畫題: Titles on Painting) and GyeSong (偈頌: Poetry Type of Buddhist Chant) between Zen Sect Buddhism and Doctrine Study Based Buddhism, which are different from each other in viewpoints. Second, Bo Myoung's MokWooDo introduces the discipline processes from MiMok (未牧: Before Tamed) to JinGongMyoYu (眞空妙有: True Vacancy is not Separately Existing) of SsangMin (雙泯: the Level where Only Core Image Appears with Every Other Thing Faded out) that lie on the method called BangHalGiYong (棒喝機用: a Way of Using Rod to Scold). On the other side, however, it puts its ultimate goal onto the way to overcome even such core image of SsangMin. Third, Kwak Ahm's SimWooDo shows the discipline processes of JeomSu from SimWoo (尋牛: Searching out a Bull) to IpJeonSuSu (入鄽垂手: Entering into a Place to Exhibit Tools). That is, it puts its ultimate goal onto HwaGwangDongJin (和光同塵: Harmonized with Others not Showing your own Wisdom) where you are going together with ordinary people by going up to the level of 'SangGuBori (上求菩提: Discipline to Go Up to Gain Truth) and HaHwaJungSaeng (下化衆生: Discipline to Go Down to Be with Ordinary People)' through SaGyoIpSeon (捨敎入禪: Entering into Zen Sect Buddhism after Completing a Certain Volume of Doctrine Study), which are working for leading the ordinary people of all to finding out their Buddhist Nature. Fourth, Shimiz Shunryu (清水春流)'s painting YuGaSipMaDo (儒家十馬圖: Painting of Ten Horses of Confucian School) borrowed Bo Myoung's MokWooDo. That is, it borrowed the terms and pictures of Buddhist School. However, it features 'WonBulIpYu (援佛入儒: Enlightenment of Buddhist Nature by Confucianism)', which is based on the process of becoming a greatly wise person through Confucian study to go back to the original good nature. From here, it puts its goal onto becoming a greatly wise person, GunJa who is completely harmonized with truth, through the study of HamYang (涵養: Mind Discipline by Widening Learning and Intelligence) that controls outside mind to make the mind peaceful. Its ultimate goal is in accord with "SangCheonJiJae, MuSeongMuChee (上天之載, 無聲無臭: Heaven Exists in the Sky Upward; It is Difficult to Get the Truth of Nature, which has neither sound nor smell)' words from Zhōngyōng. Fifth, WonMyeongNhoYin (圓明老人)'s painting SangSeungSuJinSamYo (上乘修真三要: Painting of Three Essential Things to Discipline toward Truth) borrowed Bo Myoung's MokWooDo while it consists of totally 13 sheets of picture to preach the painter's will and preference. That is, it features 'WonBulIpDo (援佛入道: Following Buddha to Enter into Truth)' to preach the painter's doctrine of Taoism by borrowing the pictures and poetry type chants of Buddhist School. Taoism aims to become a miraculously powerful Taoist hermit who never dies by Taoist healthcare methods. Therefore, Taoists take the mind discipline called BanHwanSimSeong (返還心性: Returning Back to Original Mind Nature), which makes Taoists go ultimately toward JaGeumSeon (紫金仙) that is the original origin by changing into a saint body that is newly conceived with the vital force of TaeGeuk abandoning the existing mind and body fully. This is a unique feature of Taoism, which puts its ultimate goal onto the way of BeopShinCheongJeong (法身淸淨: Pure and Clean Nature of Buddha) that is in accord with JiDoHoiHong (至道恢弘: Getting to Wide and Big Truth).