• The Korean Journal of Malacology
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• v.30 no.3
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• pp.249-258
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• 2014

Phytoplankton species composition and ecological index (diversity, evenness, richness and dominance) were analysed from April 2013 to March 2014 at 10 stations of cupped oyster, Crassostrea gigas culture area in Iwon coast, Korea. Seasonal and positional variation of phytoplankton standing crops, biomass, dominant species and water quality were distinctively different according to occasionally inflow of Iwon dam reservoired water. The composition of phytoplankton species were Bacillariophyceae 98, Dinophycease 22, Chlorophycease 13, Cyanophyceae 8, Silicofalgellate 4, Euglenophyceae 2, Cryptophyceae 1 species. The most dominant species was Bacillariophyceae as 64.0%. The highest biomass of phytoplankton recorded in September as $40,910{\times}10^3$ cell/L at the station 1, near from inland water inflow area. Ecological indices (diversity, richness, evenness, and dominance index), used for structural change of phytoplankton community and water quality (temperature, dissolved oxygen, salinity) showed difference of spatiotemporal property also.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.2 s.109
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• pp.48-59
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• 2005

The purpose of this study was to examine the ecological characteristics of herbaceous communities by systematic and scientific analysis of their structure and diversity in the Midongsan Arboretum and to offer raw data for a long-tenn monitoring study. The importance value and diversity index of species appearing in twenty plots from July to September, 2004 were analyzed and a management plan for these communities is presented. Vascular plants were represented by 60 taxa of 23 families, 51 genera, 50 species and 10 varieties. Based on the results of importance value analysis, the most dominant species was Artemisia princeps var. orientalis, followed by Setaria viridis and Erigeron canadensis. The diversity index analysis showed that plot no. 5 had the highest H' and H'_{max}$(2.0135 and 2.6391). It's species composition was comparatively more diverse and it's structure more stable than other plots. Artemisia montana and Dactylis glomerata showed the highest correlation between species. Because herbaceous communities are important biological habitats and provide important function in environmental conservation, it is important to properly preserve these communities. At the same time, in order to preserve genetic resources and improve spatial function, it may be necessary to consider removing herbaceous communities in certain areas. In the future, the relations between physicochemical soil properties and herbaceous communities should be examined and community movement should be studied.

• The Journal of Korean Physical Therapy
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• v.23 no.6
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• pp.49-53
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• 2011

Purpose: The purpose of this study is to investigate whether dual-hemisphere transcranial direct current stimulation (tDCS) could induce more cortical activity, compared to single-hemisphere, using functional MRI (fMRI). Methods: One right-handed healthy subject was recruited. Three phases of dual-hemisphere tDCS (i.e. anodal tDCS over the left-dominant primary sensoriomotor cortex (SM1) and cathodal tDCS over the right-non dominant SM(1) were consecutively delivered on to a subject, during fMRI scanning. The voxel count and the intensity index in the averaged cortical map were analyzed among the three tDCS phases. Results: Our result showed that cortical activation was observed on all the three phases of the dual-hemisphere tDCS. Voxel count and intensity index were as following; 912 and 4.07 in the first phase, 1102 and 3.90 in the second phase, 1031 and 3.80 in the third phase. Conclusion: This study demonstrated that application of the dual-hemisphere tDCS could induce cortical activity and maintain to recruit cortical neurons. Our findings suggested that application of dual-hemisphere tDCS could produce efficiency of the ongoing tDCS effect to facilitate cortical excitability.

• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.67-72
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• 2001

The algae in Dongbok reservoir consists of 6 class, 14 orders, 30 families, 63 genera, 145 species, 13 varieties, and 1 formula in 159 taxa during jan. 1995 to Dec. 1999. Species numbers according to major taxa were appeared as Chlorophyceae 80 taxa, Bacillariophyceae 28 taxa, and Cyanophyceae 17 taxa. The ratio of total standing crops were Bacillariopyceae 44%, Cyanophyceae 30%, and Chlorophyceae 225. Various species remarkably appeared during fall to early winter comparing with other seasons. Stnading crops of algae decreased from 1.1~3.7 million units/$\ell$ in 1995 to below 1.0 million n\\units/$\ell$ ever after 1996. Species number was very variable as 9~37 in down stram comparing with 12~34 in middle stream, 15~24 in upper stream. Species diversity indices were 1.1~4.0 in 1995, 1.5~3.5 in 1996~1997, 2.1~3.6 in 1998, and 0.3~3.4 in 1999. Dominant indices were 0.35~0.97 in 1995, 0.44~0.86 in 1996, 0.43~0.89 in 1997, 0.39~0.80 in 1998, and 0.45~0.97 in 1999.

• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.24.2-24.2
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• 2008

We have examined the relative contributions of representative space weather proxies (geomagnetic aa index) to global warming (Global temperature anomaly) and compared them with that of green house effect characterized CO2 content from 1868 to 2005. For this we used Hadcrut3 temperature anomaly (Ta) data, aa index taken at two anti-podal subauroral stations (Canberra Australia and hartland England), and the CO2 data come from historical ice core records. From the comparison between Ta and aa index, we found several interesting results: (1) the linear correlation coefficient between two parameters increases until 1990 and then decreases rapidly, and (2) the scattered plots between two parameters shows different patterns before and after 1990. A partial correlation of Ta and two quantities (aa, CO2) also shows that the geomagnetic effect (aa index) is dominant until about 1990 and the CO2 effect becomes much more important after then. These results imply that the green house effect become very important since at least 1990. For a further analysis, we simply assume that Ta (total) = Ta (aa) + Ta (CO2) and made a linear regression between Ta and aa index from 1868 to 1990. A linear model is then made from the linear regression between energy consumption (a proxy of CO2 effect) and Ta (total) - Ta (aa) since 1990. This linear model makes it possible to predict the temperature anomaly in 2030, about 1 degree higher than the present temperature, which is much larger than in the previous century.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.79.3-80
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• 2016

We have investigated the correlation analysis between global temperature anomaly and two main factors: geomagnetic activity (aa index) of Earth external factor and CO2 of Earth internal factor. For this, we used NOAA Global Surface Temperature anomaly (Ta) data from 1868 to 2015. The aa index indicates the geomagnetic activity measured at two anti-podal subauroral stations (Canberra Australia and Hartland England) and the CO2 data come from historical ice core records and NOAA/ESRL data. From the comparison between (Ta) and aa index, we found several interesting things, First, the linear correlation coefficient between two parameters increases until 1985 and then decreases rapidly. Second, the scattered plot between two parameters shows a boundary of the correlation tendency (positive and negative correlation) near 1985. A partial correlation of (Ta) and two main factors (aa index, CO2) also shows that the geomagnetic effect (aa index) is dominant until about 1985 and the CO2 effect becomes much more important after then. These results indicate that the CO2 effect become very an important factor since at least 1985. For a further analysis, we simply assume that Ta = Ta(aa)+Ta(CO2) and made a linear regression between (Ta) and aa index from 1868 to 2015. A linear model is then made from the linear regression between energy consumption (a proxy of CO2 effect) and Ta-Ta(aa) since 1985. Our results will be discussed in view of the prediction of global warming.

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.264-270
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• 2005

The ichthyofauna and fish community structure were investigated at three areas in Lake Chungju from April to October 2004. During the surveyed period,32 two species belonging to 12 families were collected. Dominant species in number was hemibarbus labeo (relative abundance : 23.2%) and subdominant was Erythroculter erythropterus (12.1%). Siniperca scherzeri (9.2%), and Pseudogobio esocinus (8.6%) were also numerous. There were nine Korean endemic species belonging to six families including Acheilognathus yamatsutae. The number of fish species collected was 28 in Danyang, 17 in Jecheon, and 15 in Chungju. Highest dominant index calculated was 0.670 in Chungju, and highest diversity index calculated was 2.442 in the Danyang area. We need closer observation of population fluctuation of some species, including H. labeo, the dominant species by biomass in Lake Chungju.

• The Korean Journal of Ecology
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• v.19 no.5
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• pp.417-430
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• 1996

This study was conducted to investigate the developmental process of plant community during the secondary succession and the dynamics of soil properties in the burned and unburned areas of Mt. Ch’oly-san. Owing to the forest fire occurred on April, 1989, the red pine(Pinus densiflora) forest and its floor vegetation were burned down. The floristic composition of burned and unburned areas were composed of 53 and 49 species of vascular plants, respectively. The dominant species based on SDR4 of the burned sites were lespedeza cyrtobotrya (89.62), Miscanthus sinensis var. purpurascens (62.50), and Carex humilis (58.73), Quercus serrata (43.33). In contrast, Pinus densiflora (83.56), Lespedeza cyrtobotrya (55.57), Miscanthus sinensis var. purpurascens (51.88) and Carex humilis (50.41) were dominant in the unburned area. The biological spectra showed the $H-D_1-R_5-e$ type in both the burned and unburned areas. The indices of similarity ($CC_S$) between the two areas were 0.74. Degree of succession (DS) was 604 in the burned area and 802 in the unburned area. From these facts, it is assumed that the succession is rapidly progressing because of the recovery of vegetation. The species diversity ($\={H}$) and evenness index(C) in the burned and unburned areas were 0.15 and 0.18, respectively. Red pine tree did not resprout after scorch by the forest fire, but Lespedeza, Quercus, Rhododendron, Albizzia, and Zanthoxylum resprouted from the roots and trunks after the forest fire. It seems that these species are the fire-resistant species. Soil properties such as soil pH, content of organic matter, available phosphous, total nitrogen, tatal carbon, exchangeable potssium, sodium, calcium, and magnesium increased due to forest fire. These results suggest the intensity of forest fire in the study area was relatively weak. Monthly changes of soil properties were of little significance except for some cases.

• Journal of Life Science
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• v.18 no.10
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• pp.1400-1409
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• 2008

This study was carried out to offer the forensic entomological evidence to estimate the postmortem interval (PMI) based on the decomposing state of the pig carrion and the arthropod succession in exposed carrion. A total of 48 species of 28 families belonging to 7 orders were collected, and dominant insect varied with season, i. e., the Calliphoridae in March, May and October, both of the Calliphoridae and the Staphylinidae in July, and the Staphylinidae in September. The Calliphoridae was the first visiting insect throughout all the seasons as well as the index insect dominant in the early decomposing stage. The index insect in the later decomposing stage, however, was the Staphylinidae throughout all the seasons except in March. In March, the Muscidae was dominant, presumably because the flies consistently arrived throughout the extended period of decomposition of the carrion owing to the low ambient temperature of the season. In this connection, it is known that not only the decomposition stage of the carrion and the carrion-associated insect but also the climatological condition of the region have to be taken into consideration to estimate the PMI.

• Ocean and Polar Research
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• v.24 no.4
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• pp.407-417
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• 2002

Species composition and abundance of zooplankton were investigated around Dokdo in the East/Japan Sea in autumn 1999 and spring 2000. Vertical and horizontal hauls of a bongo net ($300{\mu}m$ mesh size, 60cm diameter) were made to collect zooplankton sample. Surface temperature and salinity ranged from $24.2^{\circ}C\;to\;25.1^{\circ}C$, and from 32.9psu to 33.2psu in September 1999, respectively. In May 2000, surface temperatures were $13.9^{\circ}C\;and\;14.2^{\circ}C$ at stations of A1 and A8, and salinity was 34.5psu at both stations. Zooplankton community was dominated by copepods which comprised 61% (September) and 60% (May) of total numerical abundance, respectively. The next dominant groups were appendicularians (11%) and chaetognaths (9%) in September 1999, and other crustaceans (27%) and appendicularians (4%) in May 2000. The 15.7% (September) and 23.2% (May) of copepods were in the juvenile stage of copepodites. The most dominant copepods were Oncaea media (10.4%) and Clausocalanus sp. (8.2%) which preferred warm water in September. In contrast, cold-water copepods such as Pseudocalanus minutus (9.4%) and Metridia pacifica (8.0%) were dominant in May. The results of cluster analysis based on Bray-Curtis index showed that zooplankton community were classified into two groups which represented different water mass. The average abundance of zooplankton in September was 2.1 times higher than that in May, and species number of them in September outnumbered that in May by 29 species. Zooplankton community varied in associated with a characteristic of warm waters which affected marine ecosystem differently in the study area depending on seasons.