• Korean Journal of Environment and Ecology
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• v.11 no.2
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• pp.166-176
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• 1997

To investigate the vegetation structure of Fraxinus mandshurica communith, twenty plots were set up and surveyed in the valley of Mt. Minjuji area that rises 700~1,100m above the sea level. Each plot has 100m$^{2}$ in size. By using the TWINSPAN of classification technique, total plots was divided into six communities. In the species composition analysis, it was expected that F. mandshurica community would derive from Quercus mongolica community. The F. mondshurica community was composed together of Carpinus laxiflora, Acer mono and Cornus controversa. It was turned out that F. mandshurica community was edaphic climax because the competition species not appeared. In the DBH distribution analysis, F. mandshurica appeared through all layers, and species diversity showed lower index(Shannon's index 0.72~0.82) because the community was stable. The number of mean individuals and species was about 111.5 and 11.0 per 100m$^{2}$ respectively.

• Journal of the Korean Geographical Society
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• v.45 no.3
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• pp.319-341
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• 2010

The purposes of this study are to classify heavy snowfall types in the Republic of Korea based on fresh snowfall data and atmospheric circulation data during the last 36(1973/74-2008/09) snow seasons and to identify typical surface synoptic climate patterns that characterize each heavy snowfall type. Four synoptic climate categories and seventeen regional heavy snowfall types are classified based on sea level pressure/surface wind vector patterns in East Asia and frequent spatial clustering patterns of heavy snowfall in the Republic of Korea, respectively. Composite analyses of multiple surface synoptic weather charts demonstrate that the locations and intensity of pressure/wind vector mean and anomaly cores in East Asia differentiate each regional heavy snowfall type in Korea. These differences in synoptic climatic fields are primarily associated with the surge of the Siberian high pressure system and the appearance of low pressure systems over the Korean Peninsula. In terms of hemispheric atmospheric circulation, synoptic climatic patterns in the negative mode of winter Arctic Oscillation (AO) are also associated with frequent heavy snowfall in the Republic of Korea at seasonal scales. These results from long-term synoptic climatic data could contribute to improvement of short-range or seasonal prediction of regional heavy snowfall.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.626-637
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• 2013

We measured the grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS) and trace metals (Al, Fe, Cu, Pb, Zn, Cd, Cr, Mn, Hg, and As) of intertidal surface sediment collected from 11 islands (62 stations) in the southern region of Jeollanam Province. The objective of this research was to evaluate the organic matter and trace metals contaminations of sediments from coastal island tidal flats. Surface sediment texture was characterized as follows: mud, sandy silt, muddy sand, and slightly gravelly sand facies. The finer sediments are mainly dominated in the northern part of each island. The concentrations of IL, COD, AVS and some trace metals (Al, Fe, Zn, Cr, Cu, and Hg) were higher in the northwestern part of Wan Island and the area between Gogeum and Sinji Islands, and were associated with relatively finer sediment, as compared to other locations. The concentrations of Mn, Pb, Cd, and As were higher in the northwestern and southeastern parts of Geoguem and Pyungil Islands, but were not correlated with mean grain size. Based on sediment quality guidelines (SQGs), the concentrations of trace metals were lower than the values of effect range low (ERL), used in United States, and threshold effects level (TEL), used in Korea, with exception of As. Similarly, the intertidal sediments were moderately contaminated with As, based on the the enrichment factor (EF) and the geoaccumulation index ($I_{geo}$). The high concentration of As in intertidal sediments from this study region may be due to the input of naturally or artificially contaminated submarine groundwater, contaminated waste from seaweed aquaculture operations and/or land-based seaweed processing facilities. Further studies are needed to identify the sources of As in this study region, and to determine the effects of As contamination on coastal ecosystem.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.339-348
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• 2012

To survey the seagrass distribution in Jeju and Chuja Islands, we directly observed seagrass beds using SCUBA in July, 2011. Distributional area, species composition, morphology, density, and biomass of seagrasses and environmental characteristics were examined in investigation sites. In particular, three protected seagrass species (Zostera marina, Z. caulescens and Z. caespitosa) were found in the investigation areas. While the three species were found in Chuja Island, only Z. marina was distributed in Jeju Island. Z. marina was distributed only north-eastern coast of Jeju Island, and the total coverage was $238,572m^2$. Total seagrass coverage of Chuja Island was $23,584m^2$. In detail, Z. caulescens Z. caespitosa and Z. marina were 21,216, 1,870 and $498m^2$, respectively. Of these, Z. marina was found from the intertidal to subtidal zones of 5m MSL (mean sea level) depth. Z. caespitosa and Z. caulescens were found in subtidal zones of 3~4 m and 4~6m MSL depth, respectively.

• Journal of Nutrition and Health
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• v.9 no.1
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• pp.60-68
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• 1976

A group of 132 pre-school children with a mean age of six years and one month was the subjects of this investigation. These children were members of three nursery schools locating in Kwang-ju city. Each child's mother replied to a questionaire which included 42 food items and 4 questions. The results showed that the food preference of each child was variable and the group as a whole expressed more positive than negative feelings. The average number of foods liked per child was 22.9(range: $7{\sim}42$) among 42 food items. Peach, Apple, Strawberry, Laver, Egg, Tomato, Sweet Potato, Tangerine Orange and Beef were ranked in descending order of 'like' ratings. The average number of foods refused was 4.9 (range: $0{\sim}25$). Onion, Liver, Red Pepper Leaf, Root of Bellflower, Taro, Wild Seasame Leaf, Egg Plant, Cabbage, Water Cress and Bracken were ranked in descending order of 'refuse' ratings. The odor of hurting feelings, the hot taste and the flabby texture were the reasons why the children refused these foods. The average number of foods unexperienced was 4.4 (range: $0{\sim}14$). Kidney, Dried Small Whitebail, Tangle (DA SHI MA), Liver, SA RI Mushroom, Acorn Mook, Dried Fragrant Mushroom, Pine Agaric, Root of Bellflower and Ped Pepper Leaf were ranked in descending order of 'unexperience' ratings. Children's 'like' rating toward total foods was 57.3% and the 'refuse' rating was 11.7%. Among eight food groups, fruits showed the highest favority (91.4%) and mushroom showed the least (25.9%). The difference between male and female in the preference of total foods did not showed significant level. But the difference were significant in those of individual food groups; other vegetables, green and yellow leafy vegetables, mushrooms(above, p.<01), fishes and shellfish and sea weeds (above, p<.05). Children who had experienced meals missed rated 59.1% and 34.1% of these children missed meals once a week. The main reason for maels missed was due to the heavey snacks before meal time. Children who had snacks twice a day rated 45.6%. Main foods used as their snacks were starch foods (Cake, Biscuit, Sweet Potato) and citrous foods (Fruits, Apple, Tangerine).

• Journal of Navigation and Port Research
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• v.33 no.10
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• pp.685-690
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• 2009

International Maritime Organization (IMO) recommends the installation of an Automatic Identification System (AIS) according to requirements by SOLAS to avoid maritime collision. AIS provides traffic information of other ships that may be used for maritime traffic control, SAR (Search and Rescue) and collision avoidance to apply safety management. In this paper, preliminary results to implement an aeronautical surveillance transceiver using AIS transceiver based on ADS-B concepts are described. Although altitude information is not required for AIS since the AIS is operated at MSL (Mean Sea Level), altitude information can be extracted by a GPS (Global Positioning System) chip-set in the AIS transceiver. ADS-B transceiver is implemented by defining a surveillance message format including the altitude information and modifying SOTDMA (Self-Organizing Time Division Multiple Access) protocol. Ground tests and flight tests are performed to validate the implementation results.

• Atmosphere
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• v.20 no.3
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• pp.379-386
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• 2010

Impact of global warming on the ocean environment is reviewed based on most recently published publications. The most significant impact of global warming on marine environment is due to the melting of mountain and continental glaciers. Ice melting causes slow down and/or shut down of thermohaline circulation, and makes hypoxic environment for the first time, then makes anoxic with time. This can cause decreasing biodiversity, and finally makes global extinction of animals and plants. Furthermore, global warming causes sea-level rise, soil erosion and changes in calcium carbonate compensation depth (CCD). These changes also can make marine ecosystem unstable. If we emit carbon dioxide at a current rate, the global mean temperature will rise at least $6^{\circ}C$ at the end of this century, as predicted by IPCC (Intergovernmental Panel on Climate Change). In this case, the ocean waters become acidic and anoxic, and the thermohaline circulation will be halted, and marine ecosystems collapsed.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.9 no.2
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• pp.47-58
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• 2003

To closely examine the effects of the massage treatment as one method of curing hypertension by exploring the effects that one-time circulation-centered massage has on a hypertensive's blood pressure, this study selected as the subject ten among fifty-year-old essential hypertensives visiting N clinic, and measured and compared their blood pressures before and after I gave them massage. After stabilizing them, I measured their blood pressures. In their prone and supine postures, I gave them rubbing massage for twenty minutes from positions proximal to their hearts to ones distal from their hearts to help their artery circulation and circulation-centered stroking massage for ten minutes from positions distal from their hearts to ones proximal to their hearts to help their vein circulation. After the massage, I had them rest for five minutes and measured their blood pressures. Regarding each item analyzed, I calculated the mean and standard deviation before and after the massage. The difference before and after the massage was tested by corresponding t-test and the level of significance was made p<0.05. The findings are as follows. First, systolic pressure was $157.70{\pm}7.48$ before the massage and $143.00{\pm}9.39$, which is less than before the massage, after the massage, showing statistically significant difference (p<.05). Secondly, diastolic pressure was $97.80{\pm}6.56$before the massage and $95.20{\pm}5.18$, which is less than before the massage, after the massage, not showing statistically significant difference (p<.05).

• Plant Resources
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• v.6 no.2
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• pp.120-128
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• 2003

The objectives of this study, an analysis of the variation for leaf and fruit characteristics among the selected ten populations of Sorbus commixta Hedl. could be used for the conservation of gene resources and could provide information to superior trees selection. The results obtained from this study can be summarized as follows; Approximately, the Mt. Sungin population at Ulleung island showed larger values in overall characteristics and populations. On the other hand, Mt. Halla population at Jeju island showed the smaller values of the overall characteristics and populations. ANOV A tests showed that there were statistically significant differences in all leaf characteristics among the populations as well as individual trees within populations. But, for fruit characteristics, differences were statistically significant only among the populations. Cluster analysis using single linkage method based on leaf and fruit characteristics showed that ten selected populations of S. commixta in Korea could be clustered into three groups. Group I is Mt. Sungin at Ulleung island, Group II is Mt. Halla at Jeju island, and Group III comprises Osan, Mt. Kaji, Mt. Duckyoo, Mt. Balwang, Mt. Sobaek, Mt. O-dae, Mt. Jiri, and Mt. Taebaek. The selection level based on major agronomic traits, which are the Number of Fruit per Fruiting Lateral(NFL) over 50, and Fruit Length(FL) and Width(FW) over 10 mm, and Weight of 100 Fruit(WFI00) over 66 g, was applied on 100 sample trees, and five trees were selected. The selection effects from selected trees in NFL, FL, FW, and WF100 were evaluated as 132%, 151 %, 142%, and 264% compared to the mean of those 100 sample trees, respectively. Especially, Ulleung 2 showed excellent values that NFL and WFI00 were 95, and 69 g, respectively, suggesting a promising new cultivar for larger fruit and high productivity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.594-599
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• 2001

In a sandy shore surf zone of Dolsan Island, diel, tidal and seasonal effects on abundance of Acartia omorii were investigated at three sites, the bottom and surface of 1 m depth and water's edge using a sledge-net. Of these sites, the abundance of A. omorii was the highest in the bottom. Seasonal abundance data showed that A. omorii was more abundant in winter than other seasons. During the study period, the abundance of A. omorii was always higher during ebb tide than flood, The distribution patterns of A. omorii were more influenced by tide than diel change, Strong current during spring tide possiblely affected the diel migration pattern, In winter A. omorii showed a diel vortical migration in neap tide, whereas it showed a reverse vortical diel migration in spring tide. Distribution centers were located at a layer of $50\~100\;cm$ below mean sea level (MSL) during neap tide, and then it moved slightly upward during spring tide.