• Bulletin of the Korean Space Science Society
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• 2006.10a
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• pp.106-106
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• 2006

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.1162-1163
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• 2005

• Bulletin of the Korean Space Science Society
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• 2001.11a
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• pp.65-65
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• 2001

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.4
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• pp.419-432
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• 1998

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.389-390
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• 2002

• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.19-22
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• 2004

Seasonal changes of topograpy, sediment grain size and accumulation rate on the Gomso-Bay tidal flat(Fig. 1), west coast of Korea, have studied in order to understand the seasonal accumulation pattern and preservation potential of tidal-flat sediments. Seasonal levelings across the tidal flat show that the landward movement of both intertidal sand shoals and cheiers accelerates during the winter and typhoon period, but it almost stops in summer when mud deposition is instead predominant on the middle to upper tidal flat. Seasonal variations of mean grain size were largest on the upper part of middle tidal flat where summer mud layers were eroded during the winter and typhoon periods(Fig. 2). Measurements of accululation depths from sea floor to basal plate reveal that accumulation rates were seasonally controlled according to the elevation of tidal-flat surface(Table 1) : the upper flat, where the accumulation rate of summer was generally higher than that of winter, was characterized by a continuous deposition throughout the entire year, whereas on the middle flat, sediment accumulations were concentrated in winter realtive to summer, and were intermittently eroded by typhoons. The lower tidal flat were deposited mostly in winter and eroded during summer typhoons. Cancores taken across the tidal flat reveal that sand-mud interlaers resulting from such seasonal changes of energy regime are preserved only in the upper part of the deposits and generally replaced by storm layers downcore(Fig. 3). Based on above results, it is suggested that the storm deposits formed by winter stors and typhoons would consist of the major part of the Gomso-Bay deposits(Fig. 4).

• Sleep Medicine and Psychophysiology
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• v.12 no.2
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• pp.111-116
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• 2005

Objectives: Although many reports have been written on seasonal variations in mood and behavior in foreign countries, few reports have dealt with Korean adolescents, except medical students. The goal of this study was to estimate the frequency of seasonal variations in mood and behavior among Korean high school students. Methods: A total of 656 high school students living in southeastern Seoul participated in this study. The subjects were investigated with the Korean translated version of the Seasonal Pattern Assessment Questionnaire (SPAQ), and their responses were evaluated for seasonal patterns in mood and behavior change according to Kasper's criteria to make SAD (seasonal affective disorder) or SSAD (subclinical seasonal affective disorder) diagnosis. Results: A total of 565 subjects completed the questionnaire and the responses (M：F=324：241) were collected and used for analysis. The mean age was 16.73 (SD=0.65) years, and mean global seasonality score 5.88 (SD=4.72). Of the respondents, 413 (73.1%) reported problems related with seasonal changes. Total prevalence rates were 13.6% for SAD, 10.8% for S-SAD. The estimated frequencies were 5.1% for summer SAD, 3.2% for summer S-SAD, 0.5% for winter SAD and 1.1% for winter S-SAD. The prevalence rate of summer SAD or S-SAD was higher than winter SAD or S-SAD. Conclusion: The subjects showed a higher prevalence rate of summer type than winter type in SAD or S-SAD. These results were similar to those of other studies carried out in East Asian countries. However, the unpleasant feelings resulting from high temperature and humidity in summer rather than depression may have influenced the results. Therefore, it is necessary to make new SAD criteria of the SPAQ suitable for East Asian countries.

• Journal of the korean society of oceanography
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• v.32 no.2
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• pp.63-68
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• 1997

Stable isotope profiles with fine-scale resolution were constructed from the fossil mollusk shells, Mercernaria mercernaria, obtained from the late Pleistocene transgressive deposits of Gomez Pit, Virginia, USA. Incremental sampling were made along the axis of maximum growth to provide high-resolution ${\delta}^{18}$O and ${\delta}^{13}$C records. The ${\delta}^{18}$O shell profiles exhibit a series of pronounced cycles in the overall amplitude, corresponding to strong seasonal variations in temperature, which is apparently positive environmental variable. Contrasts between the patterns of ${\delta}^{18}$O and ${\delta}^{13}$C profiles reflect the relationship influencing the seasonal carbon cycling in the shallow marine environment. Positive anomalies of the ${\delta}^{13}$C values during the summer were observed to be out of phase with the ${\delta}^{18}$O profile. Such relatively heavier carbon source may be alternated due to seasonal methanogenesis during the summer. A hypothesized methane-based system may be operated in the shallow and marginal marine environment, resulting in a ${\delta}^{13}$C enriched bicarbonate pool, in which the heavier isotope seems to be incorporated to the shell carbonate.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.373-377
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• 2002

The Measurement of Pollution in the Troposphere (MOPITT) instrument is an eight-channel gas correlation radiometer launched on the Earth Observing System (EOS) Terra spacecraft in 1999. Its main objectives are to measure carbon monoxide (CO) and methane (CH4) concentrations in the troposphere. This work analyzes tropospheric carbon monoxide distributions using MOPITT data in East Asia and compared ozone distributions. In general, seasonal CO variations are characterized by a spring peak and decreased in the summer. Also, this work revealed that the seasonal cycles of CO are spring maximum and summer minimum with averaged concentrations ranging from 118ppbv to 170ppbv. The CO monthly means show a similar profiles to those of O3. This fact clearly indicates that the high concentration of CO in spring is caused by two possible causes: the photochemical CO production in the troposphere, transport of the CO in the northeast Asia. The CO and O3 seasonal cycles in northeast Asia are influenced extensively by the seasonal exchange of the different types of air mass due to the Asian monsoon. The continental air masses contain high concentrations of O3 and CO due to higher continental background concentrations and sometimes due to the contribution of regional pollution. In summer the transport pattern is reversed. The Pacific marine air masses prevail over Korea, so that the marine air masses bring low concentrations of CO and O3, which tend to give the apparent minimum in summer.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.408-412
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• 2004

A total of 23 springs distributed in the southern and northern sides of Mt. Hala in Jeju Island were seasonally sampled and analyzed for their major ion chemistry and oxygen and hydrogen isotope compositions to investigate their hydrogeochemical and isotopic characteristics. Dissolved ion concentrations of the south-side springs slightly increase with decreasing altitude. This indicates that dissolved ion concentrations of groundwater recharged at higher altitudes increase by water-rock interaction during the downgradient migration of groundwater through highly permeable volcanic aquifer. Dissolved ion concentrations of the north-side springs also slightly increase with decreasing altitude, but dramatically increase at ～300 m.a.s.l. This may indicate a sudden input of contaminants to the north-side groundwater system around ～300 m.a.s.l. Springs located in areas above ～300 m.a.s.l. have very low concentrations of dissolved ions, showing little seasonal variations. Whereas springs located in areas below ～300 m.a.s.l. show a big seasonal variation in the concentration of dissolved ions. Seasonal variation of oxygen isotope compositions of springs is ～3$\textperthousand$ for high-altitude springs (～1700 m.a.s.l.) and is ～2$\textperthousand$ near shore, indicating an attenuation of the variation through mixing with other groundwater bodies during migration.