• Journal of The Geomorphological Association of Korea
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• v.26 no.4
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• pp.33-45
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• 2019

The shore platforms at Dok-do could be an important and clear indicator showing dimensional reduction of Dok-do. Especially flat type shore platforms are distributed in the southern coast of Dok-do island, composed of weak rocks against erosional resistance like interbedded lapilli tuff and massive tuff breccia. The distribution of shore platform is partially related to the wind direction at Dok-do island. The primary SW- and secondary SE winds are representative among wind directions at Dok-do, maintaining from spring to the autumn. Therefore, wide shore platforms could be developed by waves approaching from SW and SE directions in the southern coast of Dok-do. The sea stacks like Gunham-rock, Neopdeok-rock, Keungaje-rock and Jakeungaje-rock on the western coast are also considered to be formed by wave erosion from the SE direction. The shore platforms in the southern coast of Dok-do island were developed since ca. 7,000 yr. BP, when sea level raised almost to the present level. The average extension speed of shore platform was calculated to 4.0mm/y, because the broadest shore platform with the width ca. 28m was extended for ca. 7,000 years. The width's dimension of shore platform at Dok-do reflects a slow extension rate in the present, although erosional process will be faster with the sea level rise in the future.

• Journal of Environmental Science International
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• v.19 no.9
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• pp.1109-1118
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• 2010

Characteristics of precipitation and temperature in Ulleung-do and Dok-do were analyzed with hourly accumulated precipitation and mean temperature data obtained from Automatic Weather System(AWS) for latest four years(2005~2008). In Ulleung-do, total annual mean precipitation for this period is 1,574.4 mm, which shows larger amount than 1434.2 mm of whole Korean peninsula for latest 10 years(1999~2008) and 1,236.2 mm at Ulleung-do on common years(1971~2000), shows that the trend of precipitation gradually increases during the recent years. This amount is also 1.4 times larger than the total annual mean precipitation of 660.1 mm in Dok-do. Mean precipitation intensity(mm $h^{-1}$) at each time of a day in each month at Ulleung-do represents that the maximum values larger than $3.0\;mm\;h^{-1}$ were shown in May and on 0200 LST, whereas these were found in August and 0700 LST with $3.1\;mm\;h^{-1}$ in Dok-do. The difference of the precipitation amount and its intensity between Uleung-do and Dok-do is explained by the topological effect came from each covering area, and this fact is also identified from similar comparison of the precipitation characteristics for the islands in West Sea. The annual mean temperature of $14.0^{\circ}C$ in Dok-do is $1.2^{\circ}C$ higher than that of $12.8^{\circ}C$ in Ulleung-do. Trends of monthly mean temperature in both islands are shown to increase for the observed period.

• The Journal of the Petrological Society of Korea
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• v.15 no.2 s.44
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• pp.72-80
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• 2006

We report new K-Ar ages of volcanic rocks from Ulleung-do and Dok-do islands located at the middle of the Korea Sea; $3.67{\pm}0.40\sim1.89{\pm}0.29$ Ma for the Dok-do and $8.07{\pm}0.39\sim0.51{\pm}0.07$ Ma for the Ulleung-do. Such ages reveal that igneous activities of both Dok-do and Ulleung-do extend longer than previously reported. It is likely that igneous activity of Ulleung-do started as early as $8.07{\pm}0.39$ Ma which is much older than age known currently, and latest eruption and intrusion of trachyte of Dok-do lasted until $1.89{\pm}0.29$ Ma, which overlaps previously reported igneous activity of Ulleung-do. However, it seems that the main volcano-building stage of Ulleung-do started after 2.7 Ma and igneous activities of Dok-do were finished mostly before then, which suggests that Dok-do was farmed before Ulleung-do in the respect of main stages of volcano-building. Such explanation agrees well with the hypothesis that southeastern seamounts, Dok-do and Ulleung-do were sequentially generated by relatively fixed hotspot.

• Korean Journal of Plant Taxonomy
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• v.53 no.1
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• pp.60-64
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• 2023

Ipomoea cristulata Hallier f. (Convolvulaceae), native to the desert regions of the central USA to Mexico, was newly found in Gojeong-ri, Deokgwa-myeon, Namwon-si, Jeollabuk-do. This species can be distinguished from I. coccinea by leaves with 3-5 lobes, hirsute distributed adaxially, and corolla entirely red or orange-red. Its Korean name is 'Nabi-ip-yu-hong-cho' based on its butterfly-shaped leaves. We provide a detailed description, photographs, habitat details, and a taxonomic key to related taxa.

• Korean Journal of Plant Taxonomy
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• v.46 no.4
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• pp.405-412
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• 2016

We investigate the intraspecific morphological variations and geographical distributions from twelve populations (28 samples) of Orobanche coerulescens in Korea. Two main morphological types were detected, i.e., glabrous (G-type) and pilose (P-type), in the external morphology (stem, leaf, bract, calyx, and corolla). The G-type was found on Ulleung-do and Dok-do, and the P-type was observed on the coasts of South Korea, Jeju-do and Ulleung-do. The distinct difference in the morphological types and geographical distribution suggested the existence of two putative lineages with different distribution processes. O. coerulescens, distributed in very limited areas, was only identified as the G-type on Dok-do. Hence, conservation efforts should focus on protecting native habitats to conserve native species and the unique biogeographic significance of this species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.4
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• pp.421-428
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• 2017

The spatial distribution and abundance of fish species was estimate near Dok-do, East Sea of Korea by conducting midwater trawl survey with hydroacoustic method. Acoustic and midwater trawl data were collected onboard the R/V Tamgu 21 during 7-8 March 2016. Acoustic data were collected at the frequencies of 38 and 120 kHz and converted to nautical area scattering strength ($m^2/nmile^2$). Species are distributed mainly over an extent of 30-55 m, generally around southwest of Dok-do; the squid Watasenia scintillans was the dominant species found. The length-weight function and target strength of squid and other fishes were used to estimate the W. scintillans stock at 2499.1 tons and other fish at 43.8 tons during the winter season. The hydroacoustic method offers an approach for the determination of the biomass and vertical and spatial distributions of species aggregating near Dok-do, East Sea of Korea.

• Journal of the Korean earth science society
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• v.36 no.5
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• pp.447-459
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• 2015

Dok island comprises Pliocene volcanic products such as a series of volcanoclastic rocks and lavas ranging in composition from alkali basalts, and trachyandesites to trachytes. Compositional variation of the basaltic rocks can be attributed to fractional crystallization of olivine, clinopyroxene, plagioclase, and magnetite. Chemical variations among the trachyandesites are caused by fractionation of clinopyroxene, plagioclase, and magnetite with minor amphibole, while trachytes are controlled mainly by feldspar fractionation. Incompatible element abundance ratios and chondrite normalized LREE/HREE ratios (e.g., (La/Yb)c: 24.8 to 32.8 for basalts, 15.6 to 31.2 for trachyandesites) suggest that the origins of the basalts and trachyandesites involve both different degrees of partial melting and subsequent fractional crystallization processes. Trace element ratios of the basalts from Dok island are characterized by high Ba/Nb, La/Nb, Ba/Th and Th/U and isotopic ratios (Tasumoto and Nakamura, 1991) that are similar to the EM 1 type of oceanic island basalts such as Gough and Tristan da Cunha basalts.

• Journal of Haehwa Medicine
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• v.14 no.2
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• pp.177-187
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• 2005

Objective : This study is designed in order to evaluate the therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) on acute low back pain Methods : We investigated 10 patients suffering from acute low back pain were treated from Mach. 1st 2005 to Jun. 30th 2005. 10 patients, were diagnosed only straightened curvature on lateral view of lumbar spine X-ray and get Scalp acupunture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) and Do-ma acupuncture. Pain rating score(PRS) was used to assess the pain for its intensity, frequency, duration, and aggravating factors. And visual analog scale(VAS) was used, too. Results : Both Scalp acupunture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) and Do-ma acupuncture therapy showed good effect on acute low back pain. It was proved by the difference between PRS and VAS checked before treatment and what checked after treatment. In the evaluation of treatment effect, Exellent was 2(20%), Good was 5(50%), Moderate was 3(30%), Poor was 0(0%). Conclusion : The therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture on acute low back pain can be recommended as a useful therapy to treat acute low back pain.

• Journal of Acupuncture Research
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• v.23 no.3
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• pp.207-214
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• 2006

Objectives : This study is designed in order to evaluate the therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) on acute low back pain Methods : We investigated 30 patients suffering from acute low back pain were admitted to Dunsan O.M.hospital from March. 1st 2005 to December. 30th 2005. We divided into two groups: one group was treated with Scalp acupunture, another group was treated with common acupuncture. 30 patients, were diagnosed only straightened curvature on lateral view of lumbar spine X -ray. Scalp acupunture related with Governer Vessel(Dok) and Bladder Meridian(Chok-taeyang) and Do-ma acupuncture. To estimate the efficacy of treatment that applied for two groups, we compared the visual analog scale(VAS), Oswestry disabiliby index(ODI) and Straight Leg Raising Test(SLRT) score of two groups statistically. Results : Both Scalp acupuncture related with Governer Vessel(Dok) and Bladder Meridian (Chok-taeyang) and Do-ma acupuncture therapy showed good effect on acute low back pain. It was proved by the difference between VAS, ODI and SLRT score checked before treatment and what checked after treatment on each groups. Conclusion: The therapeutic effect of Scalp Acupuncture and Do-ma Acupuncture on acute low back pain can be recommended as a useful therapy to treat acute low back pain.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.125-130
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• 2008

Electrical resistivity and seismic refraction surveys were conducted to investigate geologic structures and geotechnical characteristics of the subsurface in Dok-do island, along with rock physical properties. The resistivity results in Seo-do island show that the fault adjacent to the fisherman's shelter is a normal fault and extended towards the NW direction. Bedded Rapilli Tuff in the downstream was more severely influenced in depth by weathering and erosion than Trachy Andesite II in the upstream area. The physical properties of the rocks illustrate that Trachyte and Trachy Andesite are hardest, Massive Tuff Breccia is next, and Tuffs are the most soft rocks in Dok-do island.