• Korean Journal of Ecology and Environment
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• v.35 no.2 s.98
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• pp.79-91
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• 2002

A time variable modeling study was performed for seasonal variations of vertical temperature profiles in the Okjung Lake located in upstream of the Sumjin River. Based on the model structure of the US Army Corps of Engineer's CE-QUAL-W2, the lake was divided into 3 branches, 50 longitudinal segments and 49 vertical layers and vertical profiles of water temperature and current velocity were simulated over one year. The model results were calibrated and verified against vertical profiles of water temperature measured every month from March 1998 to February 1999 at 5 different locations. The model results showed a good agreement with the field measurements. The hydrologic balance during this period was validated by comparing the simulated values of surface elevation level with the measured data. There was some discrepancy in July data between the model results and the fleld measurements. This could be attributed partially to the inadequacy of the model to the highly hydrodynamic nature of water body and partially to the lack of accuracy in local atmospheric temperature data during summer monsoon period. The model results have shown that there was no seasonal over-turn in most part of the Okjung Lake, where water temperature maintained above $4^{\circ}C$ over one year. In the upstream shal-low area (depth<20 meter), however, temperature at surface layer fell below $4^{\circ}C$ and water was frozen such that slight over-turn would occur during winter period. From this study, we concluded that the Okjung Lake is oligomictic. This conclusionis significantly different from the general pattern that the lakes located from $20^{\circ}C$ to $40^{\circ}C$ latitude would be warm monomictic. From the examination of simulated current velocity distribution, it was found that the upstream inflows would infiltrate into mesolimnion of the lake during hydrodynamic summer monsoon periods due to the thermal density of water.

• Journal of Dental Anesthesia and Pain Medicine
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• v.21 no.2
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• pp.119-128
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• 2021

Background: This study assessed anticipatory dental anxiety levels among 8- to 12-year-old children based on subjective and physiological measures and their correlation. The variations in anxiety based on sex, age, temperament, and academic performance were evaluated. Methods: An observational study was conducted in 60 children recruited from the waiting room over a 6-month period. The operator recorded subjective anxiety in the children using a novel visual facial anxiety scale. The operator also noted the demographic details and child's temperament using the nine dimensions of the Thomas and Chess criteria, and graded children as "easy," "slow to warm-up," and "difficult." The academic performance of the children was graded (parental ratings) on a five-point Likert scale. Physiological variables (heartrate [HR], oxygen saturation[SpO2], and blood pressure [BP]) were recorded by another evaluator. The correlation between anxiety levels and physiological variables was also assessed. The effects of age, sex, temperament, and academic performance on anxiety were evaluated. Results: The study included 60 children aged 8-12 years, including 36 boys and 24 girls. Seventy percent of children had mild to moderate levels of pre-extraction anxiety, while 30% of children demonstrated high anxiety. A significant positive correlation was noted between anxiety levels and HR (rs = 0.477, P < 0.001⁎) and systolic BP (rs = 0.294, P < 0.05), while a significant but inverse correlation was observed with SpO2 (rs = -0.40, P < 0.05). Anxiety did not influence diastolic BP. Children with difficult temperament and poor academic performance had significantly higher anxiety. Conclusion: A high percentage (70%) of children aged 8-12 years had mild to moderate anxiety prior to the extraction procedure. Increased HR, systolic BP, and reduced SpO2 were significantly associated with high levels of anticipatory dental anxiety. Pre-extraction anxiety was significantly related to the temperament and scholastic performance.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.4
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• pp.303-307
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• 2008

We investigated about change of dinoflagellate composition during October 2006 to November 2007 at the Chagwi-Do, west-part of Jeju Island. There were 32 dinoflagellate species in collected samples and 19 species Amphisolenia bidentata, Ceratium gravidum, C. hexacanthum, C. platycorne, C. praelongum, C. ranipes, C. reflexum, C. geniculatum, Dissodinium elegans, D. bicorne, Ornithocercus heteroporus, O. magnificus, O. quadratus, O. splendidus, O. steinii, Protoperidinium excentricum, Pseliodinium vaubanii, Ptychodiscus noctiluca, Pyrocystis hamulus of collected dinoflagellate species were rare and unrecorded species from around the Korean Peninsula. The quantities by month of these tropical oceanic species, Ornithocercus were 28, 22, 0, 3 and $502\;cells/m^3$ in October 2006, February, April, September and November 2007 respectively. The abundance of genus Ornithocercus for whole dinoflagellate species were 8, 3.9, 0, 0.2 and 97.9% respectively. These results suggest that the coast of Korean Peninsula is getting warm by global warming.

• Journal of Korean Public Health Nursing
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• v.12 no.1
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• pp.116-131
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• 1998

This study was undertaken to obtain the menstrual patterns and menstrual discomforts in women university students. For the data collection, self-administered questionnaire survey was made from December 10, 1996 to January 20, 1997 among the 180 women university students in Seoul. The resultant data were processed by SAS program for frequency, proportion, and chi-square test. The results of this study are as follows ; 1) The mean age of the subjects was 20.6 years old. The mean height was 162cm and weight was 52.3Kg. $26.9\%$ of the subjects responded that they had experienced the unbalanced diet, $56\%$ the irregular meal, $39.6\%$intermittent dizziness, and $63.4\%$ the premenstrual syndrome. $53.7\%$ had feeling that skin temperature of their four extremities was 'a little lower than others'. The mean BMI(Body Mass Index) was 19.8, 'normal level' was $41.8\%$. $18.7\%$ responded that their characters were 'introspective ones'. The mean age of menache was 13.8 years old. The subjects responded that the mean number of pads they used per day during menstrual periods was 4.6 sheets. The mean duration of menstruation was 5.4 days, $10.4\%$ responded that their menstrual cycles were 'extremely regular', $44.8\%$ was 'regular', $36.6\%$ was 'a little irregular', and $8.2\%$ was 'extremely irregular'. Out of them who had experienced the dysmenorrhea, $21.3\%$ had family history of dysmenorrhea in connection with their mother and $35.0\%$ in their sisters. The mean of the first time that they experienced dysmenorrhea was 15 years old. $94\%$ of the subjects responded that they had experienced the dysmeorrhea. $47.6\%$ of the subjects responded that they experienced the dysmenorrhea 'monthly' and $52.4\%$ 'intermittently'. $53.0\%$ of them who had experienced dysmenorrhea responded that dysmenorrhea was the severest 'on the first menstrual day' and $22.4\%$ 'on the second day'. $48.8\%$ of them who had experienced dysmenorrhea responded that the most painful region was 'low abdomen'. $40\%$ of them who had experienced dysmenorrhea responded that they used 'analgesics' to soothe dysmenorrhea, $24.8\%$ used nothing, $18.4\%$ lay in their beds or slept, and $12\%$ made their 'low abdomen' warm. $70.3\%$ who had used analgesics because of dysmenorrhea took analgesics 'one or two times per month', $25.7\%$ 'intermittently', and $4.0\%$ more than 3 times per month. The analgesics which they used were 'geworin$(33.8\%)$,' 'penzal$(32.4\%)$', 'tyrenol$(18.9\%)$', and 'aspirin$(4.2\%)$'. $(47.9\%)$ of them who took analgesics because of dysmenorrhea responded that the duration of analgesics effect was '4 to 8 hours'. $15.1\%$ of them who experienced dysmenorrhea responded that they had visited the hospital. 2) The incidence of premenstrual syndrome was no significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 3) The incidence of dysmenorrhea was significant difference according to the BMI, unbalanced diet, pattern of meal, skin temperature of four extremites, and characters. 4) The incidence of analgesics usage was significant difference according to the BMI, subjects with low BMI took more analgesics than those with normal BMI (p<.05). The incidence of analgesics usage was significant difference in accordance with pattern of meal. The women who had a meal regularly took more analgesics than those who had a meal irregularly(p<.05). But the incidence of analgesics usage was no significant difference in accordance with the unbalanced diet, characters, the incidence of dizziness, skin temperature of four extremities, the incidence of premenstrual syndrome.

• Korean Journal of Environment and Ecology
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• v.25 no.6
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• pp.828-835
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• 2011

This study was conducted to understand the characteristics of bird community, migration, nesting guild, ordination analysis of observed frequency of birds at Jeju Experimental Forests (JEFs) from November 2006 to September 2007 with surveys of two areas by line transect methods and point-count methods at five areas for three consecutive days in each month. Among observed 58 species could be classified into the 24 residents, 9 summer visitors, 9 winter visitors and 16 passage migrants according to migration habit. In species composition, passage migrants are dominant birds at study areas whereas summer and winter visitors are most dominant birds at mainland's forests. We could divide two groups of bird community in the view of monthly species composition, one is November to February group, the other March to July group by ordination analysis. Number of species did not show seasonal fluctuation which is common pattern of bird community in mainland. This pattern reflects that species composition can change during breeding and non-breeding periods, but overall number of species did not change. This can be related with the high use of passage migrants at study area, also suggests that the JEFs can be highly utilized as stopover sites during migration. At mainland's forests, we can observe about five species of woodpeckers, however we just observed the only one species of White-backed Woodpeckers (Dendrocopos leucotos) at study areas. In the view of nesting guild, breeding birds can be grouped into the 9 bush-& ground nesters, 8 canopy nesters, 7 hole nesters and one house nesters. Among hole nesters, we can observe only one species of primary cavity nesters White-backed woodpecker, and the five secondary cavity nesters, that is three species of tits, tricolor flycatchers (Ficedula zanthopygia) and ruddy kingfishers (Halcyon coromanda). Therefore, White-backed woodpeckers can be regarded as a keystone species and forest practice should consider the careful conservation of this species.

• Journal of Sericultural and Entomological Science
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• v.21 no.2
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• pp.11-19
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• 1979

This has been carried out how the sericin insoluble fixations of raw silk should be with potassium alum. This is learned from the leather tanning technique which the process works with collagen, a kind of proteins. Former reports had shown such works, however, they did not consider the moisture absorbability after their process reports by using chromium alum, formalin or vinyl acetate grafting. This report, however, paid attention to protect such absorbability as well as sericin fixation, so far it may be useful for plactical use of silk. In order to clear how the sericin is fixed with such chemicals, fundermental mechanism of weding process and chemical reaction against proteins were also discussed. The obtained results of the report are as followings. 1. Alum should not be treated for raw silk with high temperature bath like other reports because such treat induces raw silk to be stiffly after the treat. 2. It is recommended that raw silk should be treated with alum solution at room temperature for more than three hours. Even in this case, the use of only alum with raw silk could to fix sericin some how, but it increased the water proofness of the silk. 3. 1% of alum solution was found to be able to fix the sericin of raw silk. 4. In case we consider only sericin fixations, a combination treat of 1% alum for three hours and 0.5% NaOH for ten minutes method showed the best result. 5. In case we consider sericin insoluble fixation and moisture absorbility, the reversive combination of the above process was found to be the best results. 6. Sericin fixing evidence was shown with drying feature curves of wed each treated silk where we could to analyze how the chemical nature is changed after each treat. 7. Deguming ratio may be obtained up to 4.3% after the alum combination treat with regular raw silk. Such ratio was considered to be good enough for the purpose when the textile is washed with warm soap water. 8. Moisture absorbability of the combination treat of alum and NaOH was found to be good enough as well as non treated silk. 9. The tenacity and elongation of the treated silk did not change even after three month. 10. Above all, this method is considered to be better process than other coloured fixing (tannin method. Cr-alum method) or smell fixing (formalin method. vinyl acetate method).

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.1
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• pp.44-57
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• 2003

Seasonal variations of bacterial abundance and production, heterotrophic nanoflagellate (HNF) abundance and HNF ingestion rates on bacteria using FLB together with environmental variables were investigated at intervals of a month in Kyeonggi Bay from December 1991 to November 1998. Bacterial abundance and production ranged from 0.38$\times$10$^{9}$ ~ 3.25$\times$10$^{9}$ cells 1$^{-1}$ (average 1.19$\pm$0.69$\times$10$^{9}$ cells 1$^{-1}$ ) and from 1.51 to 20.4 cells 1$^{-1}$ h$^{-1}$ (average 6.04$\pm$ 1.88$\times$10$^{6}$ cells 1$^{-1}$ h$^{-1}$ ), respectively. Bacterial abundance and production showed no differences at the high tide and low tide, and bacterial abundances were not different with depth, but bacterial production decreased with depth. Seasonal variation of bacterial abundance showed almost similar fluctuation pattern to those of DOC (dissolved organic carbon). HNF abundances ranged from 388 to 4,374 cells ml$^{-1}$ (average 1,344$\pm$130 cells ml$^{-1}$ ), were high in March, April, July and August. HNF abundance showed no difference between the high tide and low tide, and was not different with depth. The ingestion rates of HNF on bacteria were 1.0 to 6.3$\pm$10$^{6}$ bacteria 1$^{-1}$ h$^{-1}$ (average 3.12$\pm$0.55$\times$10$^{6}$ bacteria 1$^{-1}$ h$^{-1}$ ), resulting ingestion rates of HNF removed 19.4 to 141.4 %(average 62.3$\pm$12.0%) of bacterial production. Ingestion rates and grazing pressure of HNF on bacteria showed high correlation with HNF abundance. Although we cannot exactly discussion about seasonal variation of bacteria community in this study area where physical and chemical parameters were very complex, the results indicate that bacterial abundance and production were mainly controlled by resources supply as dissolved organic carbon and chlorophyll-a(bottom-up) except March which bacterial abundance and production uncoupled chlorophyll-a because of low dissolved organic carbon and low temperature, and were controlled by HNF grazing pressure(top-down) in the warm seasons except the winter.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.2
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• pp.153-165
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• 1995

The fluctuations of catches in set nets around Kyeongbuk Province, the eastern coast of Korea, were analyzed and investigated by on the values of CPUE(Catch Per Unit Effort per hauling), and composition of dominant species caught from 1985 to 1989. Annual CPUE values were fluctuated every year, but their trends were decreased year by year, When the values were evaluated by species, the trends of annual catches were shown decreasing in file fish(Auteridae), mackerel(Scomber japonicus), tuna(Thunnus Thynnus), rock fish(Sebastes schlegelid) and yellowtail(Seriola quinqueradiata), increasing in sardine(Sardinops melanosticta), jack mackerel(Trachurus japonicus), and herring(Clupea pallasi), and similar in squid(Todarodes pacificus) and cuttle fish(Sepiidae). The main fishing season evaluated by monthly CPUE was estimated from August to November with a little difference by regions : from August to November at Chukpyon and Kanggu, from September to November at Chuksan and Kampo, and August to December in Hupo. When the DPUE values were analyzed by species, the main fishing seasons were quite different by species. Mackerel, jack mackerel, tuna, yellowtail, and rock fish were caught mainly from September to October, file fish and squid from November to January, sardine from April to May, herring in May, and cuttle fish in April. Annual catches were shown highest level in file fish and revealed higher by sardine, jack mackerel, mackerel, squid, tuna, and yellowtail in order. But the highest catches among each species were different with seasons, and that from January to July was sardine, from November to December file fish. The main migrating seasons of file fish, mackerel, squid, tuna, and cuttle fish at Chukpyon were a little earlier than at other regions. Though the migrating seasons of jack mackerel and tuna were almost same in every regions, that of sardine were shown 3 month's difference according to regions. In the year when the warm currents were stronger than those of the normal year and their isotherms were formed from the north to south along the eastern coastal line, the annual fish catches in set net were show higher levels.

• Korean Journal of Environment and Ecology
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• v.34 no.6
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• pp.503-514
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• 2020

Climate change leads to changes in phenological response and movement of plant habitats. Korea's evergreen broad-leaved forest has widened its distribution area compared for the past 20 years, and the range of its native habitats is moving northward. We analyzed climate indices such as the warmth index, the cold index, the lowest temperature in the coldest month, and the annual average temperature, which are closely related to vegetation distribution, to predict the change in the native habitat of Lauraceae evergreen broad-leaved trees. We also analyzed the change and spatial distribution to identify the habitat climate characteristics of 8 species of Lauraceae evergreen broad-leaved trees distributed in the warm temperate zone in Korea. Moreover, we predicted the natural habitat change in the 21st century according to the climate change scenario (RCP 4.5/8.5), applying the MaxEnt species distribution model. The monthly average climate index of the 8 species of Lauraceae evergreen broad-leaved trees was 116.9±10.8℃ for the temperate index, the cold index 3.9±3.8℃, 1495.7±455.4mm for the annual precipitation, 11.7±3.5 for the humidity index, 14.4±1.1℃ for the annual average temperature, and 1.0±2.1℃ for the lowest temperature of winter. Based on the climate change scenario RCP 4.5, the distribution of the Lauraceae evergreen broad-leaved trees was analyzed to expand to islands of Jeollanam-do and Gyeongsangnam-do, adjacent areas of the west and south coasts, and Goseong, Gangwon-do on the east coast. In the case of the distribution based on the climate change scenario RCP 8.5, it was analyzed that the distribution would expand to all of Jeollanam-do and Gyeongsangnam-do, and most regions except for some parts of Jeollabuk-do, Chungcheongnam-do, Gyeongsangbuk-do, and the capital region. For the conservation of Lauraceae evergreen broad-leaved trees to prepare for climate change, it is necessary to establish standards for conservation plans such as in-situ and ex-situ conservation and analyze various physical and chemical characteristics of native habitats. Moreover, it is necessary to preemptively detect changes such as distribution, migration, and decline of Lauraceae evergreen broad-leaved trees following climate change based on phenological response data based on climate indicators and establish conservation management plans.