• Korean Journal of Plant Taxonomy
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• v.50 no.2
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• pp.154-165
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• 2020

Coastal regions are experiencing habitat changes due to coastal development and global warming. To estimate the future distribution of coastal plants on the Korean Peninsula due to climate change, the potential distribution of ten species of coastal plants was analyzed using the MaxEnt program. The study covered the eastern, western, and southern coastal areas of the Korean Peninsula. We used the distributional data of coastal plants of the East Asian region and the 19 climate variables of WorldClim 2.0. The future potential distribution was estimated using future climate variables projected from three general circulation models (CCSM4, MIROC-ESM, and MPI-ESM-LR), four representative concentration pathways (2.5, 4.5, 6.0, and 8.5), and two time periods (2050 and 2070). The annual mean temperature influenced the estimation of the potential distribution the most. Under predicted future distribution scenarios, Lathyrus japonicus, Glehnia littoralis, Calystegia soldanella, Vitex rotundifolia, Scutellaria strigillosa, Linaria japonica, and Ixeris repens are expected to show contracted distributions, whereas the distribution of Cnidium japonicum is expected to expand. Two species, Salsola komarovii and Carex kobomugi, are predicted to show similar distributions in the future compared to those in the present. The average potential distribution in the future suggests that the effects of climate change will be greater in the west and the south coastal regions than in the east coastal region. These results will be useful baseline data to establish a conservation strategy for coastal plants.

• Korean Journal of Environmental Biology
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• v.35 no.3
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• pp.361-372
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• 2017

This study described the spatial distribution of dinoflagellate cyst assemblages in the Ulsan Coastal Waters (UCW). Surface sediment samples from 15 stations revealed the occurrence of 33 species involving the Groups Protoperidinioid (51.5%), Gonyaulacoid (30.4%), Calciodineloid (9.1%), Gymnodinioid (3.0%), Diplopsallid (3.0%) and Tuberculodinioid (3.0%). The recorded cyst abundance in the UCW recorded was low ($260{\sim}1,680cysts\;g-dry^{-1}$) compared to Korean coastal waters. The abundance of heterotrophic cysts is higher in the Ulsan harbour and northwestern parts of UCW with eutrophic areas, however autotrophic species are more prevalent in the southern parts with open sea environments. The dinoflagellate cyst assemblages in the UCW were characterized by the dominance of Gonyaulax scrippsae, Protoperidinium sp. (Brigantedinium sp.), and Gonyaulax spinifera complex. The advent of the toxic dinoflagellate, Pyrodinium bahamense var. bahamense was recorded for the first time in the East-south sea of Korea. Therefore, as a result of ongoing monitoring and management for new toxic dinoflegallates from tropical or subtropical regions, analysis of dinoflagellate cyst assemblages in the UCW has been deemed necessary.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.1
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• pp.54-64
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• 2018

The age and growth of Pleurogrammus azonus in the coastal of Gangwon-do, East Sea were determined, from monthly samples of commercial catches, caught by the gill net and set net fishery from January to December in 2008. Gonadosomatic index (GSI) began to increase in September, and reached the maximum between November and December. After spawning GSI began to decrease from January. The annuli of P. azonus are formed once a year, with the boundary between opaque and translucent zones forming from December to January. The relationships between fork length (FL) and body weight (BW) were $BW=0.005FL^{3.240}$($R^2=0.963$) for females and $BW=0.006FL^{3.238}$($R^2=0.946$) for males. The FLs at annuli formation in otoliths were back-calculated from the otolith-length relationship and were adjusted to von Bertalanffy growth curves to $FL_t=70.54(1-{\exp}^{(-0.099(t+1.188))})$ for females and $FL_t=51.87(1-{\exp}^{(-0.135(t+1.697))})$ for males. Until the age of 3 years, males grew faster than females; however, from the age of 4 years, females grew faster than males. In the future, we want to study the relationship between early growth and water temperature changes in the East Sea.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.1
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• pp.96-105
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• 2018

This study examined the growth of herb plants in response to irrigation on a green rooftop area in order to select herb plants that can be used for rooftop greening. Apple Mint (Mentha suaveolens), Lemon balm (Melissa officinalis), Spearmint (Mentha spicata), Pineapple sage (Salvia elegans), Choco Mint (Mentha ${\times}$ piperita 'Choco Mint'), Ox-eye Daisy (Chrysanthemum leucanthemum), Roman Chamomile (Anthemis nobilis) and Thyme (Thymus vulgaris) showed increased growth when irrigated. Conversely, Lavender (Lavendula angustifolia ), Peppermint (Mentha ${\times}$ piperita ), Vicks Plant (Plectranthus tomentosa), Feverfew (Tanacetum parthenium), Rosemary (Rosmarinus officinalis), Tansy (Tanacetum vulgare), Lemon Verbena (Aloysia triphylla), Heliotrope (Heliotropium arborescens), Soapwort (Saponaria officinalis) and Lady's mantle (Alchemilla vulgaris) demonstrated satisfactory growth regardless of irrigation. Peppermint, Tansy, Lemon Verbena, Soapwort, and Lady's mantle seem to be suitable for green rooftop because of their overwintering ability and drought hardiness. Pineapple sage, Apple Mint and Thyme would seem to be inappropriate for rooftop greening because they showed negative growth response to drought and failed overwintering. Although Spearmint, Lemon balm, Choco Mint, Ox-eye Daisy and Roman Chamomile had reduced growth during dry conditions, they were able to overwinter satisfactorily and can be used as rooftop plants with irrigation.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.1
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• pp.69-74
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• 1977

This study has been conducted to identify physico-chemical and clay mineralogical characteristics of bentonites produced in Korea for the purpose of finding good quality bentonite for agricultural ure. The results are summarized as follows: 1. Bentonites are mainly composed of montmorillonite developed from tuffs in a lava flow. 2. Chemical properties of bentonites are: pH in $H_2O$(1:1), 7:cation exchange capacity, 60-96me/100g; content of $SiO_2$, 54-72%; ratio of $SiO_2$ to $Al_2O_3$, 4.1-10.0;oven dry loss of $H_2O$ is higher than the ingnition loss of $H_2O$. 3. The x-ray diffrection patterns of powder bentonites show peaks at $14-15{\AA}$, $4.4{\AA}$, and $2.5{\AA}$, and that of swellen one show $17{\AA}$ when treated with ethylene glycol. 4. Distribution areas of the good quality bentonites were (1) Dogu-Dong, Donghae-Myeon, Yeonil-Gun, Gyeongsangbug-Do (2) Hamyeon-Ri, Yangnam-Myeon, Weolseong-Gun, Gyeongsanbug-Do. (3) Joam-Ri, Gangdong-Myeon, Weolseong-Gun, Gyeongsangbug-Do. (4) Sanha-Ri, Gangdong-Myeon, Ulju-Gun, Gyeongsangnam-Do. (5) Sinhyeon-Ri, Gangdong-Myeon, Ulju-Gun, Gyeongsangnam-Do. (6) Yonghang-Ri, Pyeongchang-Myeon, Pyeongchang-Gun, Gangweon-Do.

• Journal of Korean Library and Information Science Society
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• v.47 no.2
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• pp.1-25
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• 2016

This study was conducted to analyze the characteristics of records related to Korea shown in the cataloging records of national libraries of the main 12 developing countries in Europe and South America. The results are as follows. To begin with, Korea-related records in most national libraries are very poor and under 0.01% of the library. Second, Korean materials usually write Korean in Roman characters except for National Library of Armenia, but there are not marked with the original Korean language and unfeasible Hangeul search. Third, on investigation of the subject distribution in sub criteria of Korea-related records, subject related to history, politics, and economy is largely shown in the highest rate. Fifth, among the Korea-related subject heading, Taekwondo is marked with distinction from Karate in most libraries except for National Library of Argentina. Dokdo is marked with the geographical name of 'Korea' in 8 national libraries and East Sea (Donghae) already is marked with 'Sea of Japan' in 7 national libraries. Amnokgang, Dumangang, and Baekdusan-related records did not search at all in most national libraries.

• The Korean Journal of Malacology
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• v.31 no.4
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• pp.263-266
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• 2015

This study was performed to determine the effect of water temperature condition on survival rate and growth of juvenile geoduck (Panopea japonica). Panopea japonica juveniles were bred for 6 weeks at 12, 15, 18, 21, 24 and $27^{\circ}C$ on incubator. Juveniles median lethal times (LT50) were 29 hours in $27^{\circ}C$, 14.5 day in $24^{\circ}C$, 37.4 day in $21^{\circ}C$. Survival rate of water temperature 12, 15 and $18^{\circ}C$ showed a high survival rate in 95.0%, 95.0% and 93.3% at 6 weeks. As a result of culturing for 6 weeks at 12, 15, 18, 21 and $24^{\circ}C$, a daily growth of shell length and total weight was 0.10 mm, 0.12 mm, 0.13 mm, 0.16 mm and 0.14 mm, and 2.21 mg, 2.65 mg, 2.84 mg, 3.13 mg and 2.93 mg. Juvenile shell length and total weight have significantly increased at $15-21^{\circ}C$. However, mortality rate has significantly increased at more than $21^{\circ}C$. As a result, appropriate water temperature for juveniles culturing considered $15-18^{\circ}C$.

• Journal of the Korea Concrete Institute
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• v.22 no.3
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• pp.399-407
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• 2010

The flexural behaviors of two types of beam members exposed to freeze-thaw cycles were evaluated. This study aims to examine the effect of freeze-thaw cycles on the behavior characteristics of reinforced concrete (RC) beams. For the purpose, a part of the beam specimens were damaged until yielding of tension reinforcement was reached, before they were exposed to 150 and 300 cycles of freeze-thaw. Cyclic tests, as well as monotonic tests, were conducted to evaluate the stiffness degradation characteristics when same cycle is repeated. The material tests showed that relative dynamic modulus of concrete exposed to 300 cycles of freeze-thaw moderately decreased to 86.8% of normal concrete, indicating that concrete used in this study has good durability against freeze and thaw damage. The results of monotonic tests showed reduction of flexural strength, ductility and stiffness of the beam specimens exposed to freeze-thaw cycles compared with those of the control speciments. In particular, BDF13 specimens, which had been subjected to artificial cracking damage, did not showed enough flexural strength to satisfy nominal moment required by current concrete structure design code. In the monotonic tests results, BF75 specimens exposed to freeze-thaw cycles showed 10% or more cyclic stiffness degradation. Therefore, it was thought that deformation of concrete in compression have to be considered in design process of members under cyclic load, such as seismic device.

• Journal of the Korean Geographical Society
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• v.34 no.5
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• pp.507-516
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• 1999

More than twenty-five major international bodies of water bear the names of particular nations or states. Many of these are not names are widely accepted, but considerable disagreement has developed in some cases. A systematic examination of the level of conflict over the use of national names for international bodies of water indicates that conflict is most likely to develop where shifting power relations among interested states produce concern about the hegemonic ambitions of the state after which the body of water is named. This is the case in the three situations where considerable contention exists over the use of a national name for an international body of water: the Persian Gulf/Arabian Sea, the Sea of Japan/East Sea, and the South China SealBien Dong. Cases evidencing little contention are those where either no state has a significant interest in the naming issue, or where the name that is attached to the body of water is that of a state that has not been a historic threat to others in the region. Naming international bodies of water after nations or states is potentially problematic because such appellations can connote ownership or control by a single people or political entity. An understanding of the controversies surrounding these place names requires consideration of the geopolitical context in which they are embedded.

• Journal of the Korean earth science society
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• v.36 no.4
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• pp.315-329
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• 2015

We investigated the characteristics of meteorological conditions related to the strong downslope wind over the leeward side of the Taebaek Mountains during the period 2005~2010. The days showing the strong wind exceeding $14ms^{-1}$ in Gangwon province were selected as study cases. A total of 15 days of strong wind were observed at Sokcho, Gangneung, Donghae, and Taebaek located over the Yeongdong region. Seven cases related to tropical cyclone (3 cases) and heavy snowfall (2 cases) and heavy rainfall (2 cases) over the Yeongdong region were excluded. To investigate the characteristics of the remaining 8 cases, we used synoptic weather chart, Sokcho radiosonde, Gangneung wind profiler and numerical model. The cases showed no precipitation (or ${\leq}1mm\;day^{-1}$). From the surface and upper level weather chart, we found the pressure distribution of southern high and northern low pattern over the Korean peninsula and warm ridge over the Yeongdong region. Inversion layer (or stable layer) and warm ridge with strong wind were located in about 1~3 km (925~700 hPa) over mountains. The Regional Data Assimilation and Prediction System (RDAPS) indicated that warm core and temperature ridge with horizontal temperature gradient were $0.10{\sim}0.23^{\circ}C\;km^{-1}$ which were located on 850 hPa pressure level above mountaintop. These results were summarized as a forecasting guidance of downslope windstorm in the Yeongdong region.