• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.1
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• pp.11-18
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• 2012

Daily temperature data produced by harmonic analysis of monthly climate summary have been used as an input to plant phenology model. This study was carried out to evaluate the performance of the harmonic based daily temperature data in prediction of major phenological developments and to apply the results in improving decision support for agricultural production in relation to the climate change scenarios. Daily maximum and minimum temperature data for a climatological normal year (Jan. 1 to Dec. 31, 1971-2000) were produced by harmonic analysis of the monthly climate means for Seoul weather station. The data were used as inputs to a thermal time - based phenology model to predict dormancy, budburst, and flowering of Japanese cherry in Seoul. Daily temperature measurements at Seoul station from 1971 to 2000 were used to run the same model and the results were compared with the harmonic data case. Leaving no information on annual variation aside, the harmonic based simulation showed 25 days earlier release from endodormancy, 57 days longer period for maximum cold tolerance, delayed budburst and flowering by 14 and 13 days, respectively, compared with the simulation based on the observed data. As an alternative to the harmonic data, 30 years daily temperature data were generated by a stochastic process (SIMMETEO + WGEN) using climatic summary of Seoul station for 1971-2000. When these data were used to simulate major phenology of Japanese cherry for 30 years, deviations from the results using observed data were much less than the harmonic data case: 6 days earlier dormancy release, 10 days reduction in maximum cold tolerance period, only 3 and 2 days delay in budburst and flowering, respectively. Inter-annual variation in phenological developments was also in accordance with the observed data. If stochastically generated temperature data could be used in agroclimatic mapping and zoning, more reliable and practical aids will be available to climate change adaptation policy or decision makers.

• 대한예방의학회:학술대회논문집
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• 2005.10a
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• pp.362-362
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• 2005

• The Korean Journal of Ecology
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• v.21 no.3
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• pp.263-268
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• 1998

The composition and concentration of monoterpenes in the leaves of Artemisia japonica were determined. And seasonal variation in monoterpenes of A. japonica were investigated. Samples were taken from five sites at Mt. Muhak. Monoterpenes in the leaves were analyzed using gas chromatography-mass spectrometry. The leaf monoterpene fractions were dominated by R.T. 5.026, ${\alpha}-thujene$, sabinene, ${\beta}-pinene$, cyclohexane (R.T.=12.859) and R.T. 23.149. There were marked seasonal differences in concentration and composition of leaf monoterpenes. There were many kinds of monoterpenes in leaf of spring time, however most of monoterpenes concentration was small. On the other hand, there were not many kinds of monoterpenes in late time, but monoterpene concentrations were increased.

• The Korean Journal of Ecology
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• v.22 no.3
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• pp.155-161
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• 1999

The plastochron index (PI) according to leaf development of Ambrosia artemisiifolia var. elatior were estimated. The amount and composition of monoterpenes in the leaves of A. artemisiifolia var. elatior were determined, and the seasonal monoterpene variations in representative of plastochron index were investigated. The total amount of monoterpenes in A. artemisiifolia var. elatior was increased continuously from PI 2.0, the highest amount was in PI 11.89. The major monoterpenes in A. artemisiifolia var. elatior consisted of 29 compounds. The leaf monoterpene fraction of A. artemisiifolia var. elatior were dominated by No.2, octene, α-pinene, β-myrcene, 1,3,6-octatrine, endo-borneol and (-)-bornyl acetate.

• Korean journal of applied entomology
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• v.26 no.3 s.72
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• pp.133-138
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• 1987

This study was conducted during Oct. 1986$\sim$Apr. 1987 to investigate the distribution, dominance and species diversity of soil arthropods communities from two collection sites of Suwon and Mt. Jiri. A total of 2,989 specimens of 3 orders, 20 families and 19 species were identified. In overall dominance index, Suwon community showed lower value than Mt. Jiri community. Seasonal variation dominance index were higher in Suwon community than those in Mt. Jiri community.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.383-384
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• 2001

대기 중 formaldehyde는 눈, 코, 목을 자극하고 기관지 천식, 피부 알레르기를 일으킬 뿐만 아니라 동물실험 결과 발암 가능성 물질로 여겨지고 있다(황윤정, 등 1996). 미국 EPA는 formaldehyde를 유력한 인체발암물질(probable human carcinogen, weight of evidence-Group "B1")로 분류하고 있다(IARC, 1982; Edward 등, 1991). (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.411-412
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• 2001

본 연구해역인 함평만은 서해 남부에 위치한 최대 폭 12 km이고 길이는 약17km 정도의 중대형 반폐성 만이다. 만 입구는 매우 좁고 북서쪽으로 열려져 있고 주 조류로는 만의 중앙부를 따라 북서-남동 방향으로 발달되어 있다. 함평만은 1910년대 이후 농지 확보를 위한 소규모 간척 사업으로 해안선의 변화가 있었고 비교적 육지와 연결된 큰 수계가 없어 육상기원의 환경오염원은 적은 편이다. (중략)

• 한국해양학회지
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• v.27 no.4
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• pp.290-302
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• 1992

Seasonal variations of salinity in the upper 500 m of the tropical Atlantic Ocean are examined, based on both climatological seasonal salinity observations and numerical simulations with hydrological forcing. The seasonal cycle of sea surface salinity has strong seasonal variations caused by shifts of the freshwater surplus zone (i.e. the intertropical convergence zone) and the river outflow. The climatological seasonal salinity in this analysis concurs with other independent observations described by Default (1981) and Levitus (1982), but provides more consistent patterns with temperature structure. The effect of salinity on density below 100 m depth in the tropical Atlantic is negligible compared to tat of temperature, which in the mixed layer salinity affects density significantly. The systematic difference between observed and simulated salinity is found to be the fact that the simulated salinity is higher in the subtropics than the observed salinity, and possible sources about the difference are also discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.438-445
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• 1993

Spatial and seasonal variations of community structure of demersal fishes in Asan Bay were studied using seasonal samples collected by an otter trawl from autumn 1991 to summer 1992. For each sampling station, three trawl hauls were completed to obtain a reliable sample. Of 34 species identified, Cynoglossus joyneri, Johnius belengeri, Zoraces gillii and Thrissa koreana accounted for $93\%$ of the individuals collected. The former three dominant species were more abundant on the finer sediment of the inner bay than on the sandy bottom of the outer bay. Spatial variation of community structure of demersal fishes was analysed by principal component analysis using rank correlation. The community structure did not show a spatial difference, but a clear seasonal trend. This distribution pattern seems to be related significantly to the seasonal temperature fluctuation and to the active mixing of the water by strong tidal current of the bay.

• 한국해양학회지
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• v.28 no.4
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• pp.272-280
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• 1993

The seasonal variations of water salinity and the concentration of suspended particulate matter (SPM value) have been monitored in the Keum Estuary and its adjacent coastal area. the concentrations of suspended matters show great seasonal variations with low concentrations during summer season and high concentrations during winter season. During the flood season of summer, water salinities are less than 5% in the Keum estuary, and the brackish water (salinity<28%) prevails seaward covering the entire coastal area. The concentrations decreased abruptly to the seaward from higher than 100mg/l in the Keum estuary to less than 5 mg/l in the offshore. These phenomena probably results from the rapid e\deposition of riverine suspended matters within the Keum Estuary. The seasonal variations of suspended matter concentrations in the Keum Estuary and its adjacent coastal area are interpreted as the cyclic (seasonal) sedimentation processes in the west coast of Korea, that is, replenishment and deposition of fine sediments in summer, and resuspension and seaward transport in winter.