• 미생물학회지
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• 제27권4호
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• pp.378-384
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• 1989

The numerical taxonomy of heterotrophic bacterial community in Lake Soyang was analysed. 95, 115, 88 and 75 strains which were isolated at each season from spring in 1987 to winter in 1988 were clustered by single matching coefficient. The diversity indices (H') were in the range of 0.511-1.684, and the community was most diverse in spring. THe seasonal variation of generic composition was significant. Of the domonant genera, Acinetobacter, Pseudomonas, and Flavobacterium were representative.

• 한국해양공학회지
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• 제12권1호
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• pp.107-112
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• 1998

The purpose of this study is to analyze the amount of available wave power and its characteristics related to the development of apractical system for ocean wave energy conversion in Korean coastal waters. The analysis method of wave power was established through comparison between theory and numerical simulation of deep sea wave by Inverse Fourier Transform with random phase method. Based on the results of comparison, wave power was estimated by use of data set from observed offshore and coastal waves and hindasted deep sea waves around the Korean peninsula. Annual mean wave power is estimated as about 1.8 ~ 7.0 kW for every metre of wave frontage at East sea, 1.5~5.3 kW at South sea and 1.0 ~ 4.1 kW at West sea, respectively. Mean wave power along deep sea front of coastal waters of Korea amounts to about 4.7 GW. Regional distribution and seasonal variation of wave power were discussed to develop practical utilization system of wave power of not so high grade of available wave power.

• 한국환경과학회지
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• 제8권3호
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• pp.281-286
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• 1999

This study was conduced to examine the monthly and seasonal variation of $SO_2$, TSP, $O_3$ concentration in Dongsamdong, Pusan coastal area. And the characteristics of air pollution of this area was compared to Kwangbokdong in Pusan and Taehadong in Ullungdo. Monthly mean concentration of $SO_2$ and TSP showed lower than Kwangbokdong, $O_3$ was higher than Kwangbokdong. In case of $SO_2$, seasonal variation of Dongsamdong was remarkabler thn Kwangbokdong and the concentration difference of early morning and daytime was higher than Kwangbokdong. Taehadong showed very lower concentration as background area. In case of TSP, Dongsamdong was lower concentration and smaller diurnal change than Kwangbokdong, Taehadong showed very lower concentration as backgound area. In case of $O_3$, Dongsamdong was 10ppb higher than Kwangbokdong at daytime maximum concentration, diurnal change of concentration was higher, too. In case of frequency distribution of concentration, $SO_2$, and TSP at Dongsamdong showed higher frequency in low concentration class and $O_3$ showed in high concentration class as compared with Kwangbokdong.

• 한국환경과학회지
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• 제12권4호
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• pp.399-417
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• 2003

The seasonal variation and frequency of rainfalls of Korea peninsula in Changma period show strong local weather phenomenon because of it's topographical and geographical factors in Northeast side of Asia. Based on weather entropy(statistical parameter)-the amount of average weather information-and information ratio, we can define each area's weather representativeness, which can show us more constant form included topographical and geographical factors and seasonal variation. The data used for this study are the daily precipitation and cloudiness during the recent ten years(1990-1999) at the 73 stations in Korea. To synthesize weather Entropy, information ratio of decaying tendency and half$.$decay distance, Seoul's weather representativeness has the smallest in Summer Changma period. And Puyo has the largest value in September.

• The Korean Journal of Ecology
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• 제24권6호
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• pp.353-357
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• 2001

Differential response of genotypes to temporal environmental heterogeneity may contribute to the long-term persistence of these genotypes within a population. In this experiment, we experimentally tested whether groups by season interactions for germination and seedling growth can explain genetic variability within the population. To determine whether seeds collected during the four seasons respond differentially to temperature treatments, two-way ANOVA was performed. This study indicates that seasonal environments have large effects on demography. Groups within populations respond differentially to seasonal environments by influencing population growth that may in turn influence community composition. Most importantly, the study showed that temporal heterogeneity in the environment might functions as a mechanism that maintains within-population genetic diversity.

• 한국수산과학회지
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• 제2권1호
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• pp.83-86
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• 1969

The present investigations were made with the purpose of elucidating the seasonal variation in total nitrogen content of Gelidium amansii. Monthly samples were collected from the sea near pusan, from August 1957 to June 1959. The results obtained have been summarized as follows: The maximum total nitrogen content of Gelidium amansii was observed during the months of January and February, and the minimum content was observed in June and July Thus the total nitrogen content of Gelidium amansii exhibited a considerable periodic change throughout the year. The recommended harvest time of Gelidium amansii with regard to total nitrogen content, is from May to October, but on the other hand the proper harvest time is from May to June, with respect to the season of spore-formation and its propagation.

• 한국수산과학회지
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• 제40권1호
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• pp.53-57
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• 2007

We examined seasonal variation In the abundance and species composition of shrimp communities in Doam Bay and around Naro-do, Korea. Samples were collected monthly from March 2001 to February 2002 (Doam Bay) and from December 2000 to November 2001 (Naro-do) usinga beam trawl. A total of 19 shrimp species representing eight families were collected from Doam Bay. The dominant species were Exopalaemon carinicauda, Trachysalambria curvirostris, Parapenaeopsis tenella and Crangon hakodatei, which accounted for 92.6% of individuals and 92.8% of biomass. In the Naro-do area, a total of 18 shrimp species representing eight families were collected. The dominant species were C. hakodatei and P. tenella, which accounted for 78.6% of individuals. Exopalaemon carinicauda, T. curvirostris, P. tenella, C. hakodatei and Metapenaeus joyneri accounted for 89.6% of biomass. In each season, the pattern of species appearances differed in the two areas.

• 한국수산과학회지
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• 제41권3호
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• pp.201-207
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• 2008

The seasonal variation and vertical distribution of the marine algal community were investigated using the quadrat method from February 2006 to January 2007 at 10 sites in Gwangyang Bay, Korea. In total, 48 red, 17 brown, and 13 green algal taxa were identified. The algal vertical distribution in the intertidal zone was characterized by Ulva pertusa, while the upper tidal zone was dominated by Gelidium divaricatum. The middle zone was primarily composed of Enteromorpha linza, Sargassum thunbergii, and Chondracanthus intermedia, whereas Hizikia fusiformis, Sargassum thunbergii, Gelidium amansii, and Corallina pilulifera characterized the low tidal zone. Results of cluster analysis indicated that algal composition fell into two groups, which were composed of species in the inland and open sea. In conclusion, the number of species, diversity, and abundance of vegetation in this area were remarkably reduced compared to previous studies in Gwangyang Bay.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 추계학술대회 논문집
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• pp.159-164
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• 2000

In order to clarify the seasonal variation of residual current and material transportation process in Hiroshima Bay, JAPAN, the real-time simulation of residual current and particle tracking by using Euler-Lagrange model were carried out. The calculated tidal current and water temperature and salinity showed good agreement with the observed ones. The residual currents showed the southward flow pattern at the upper layer, and the northward flow pattern at the lower layer. The flow structure of residual current in Hiroshima Bay is an estuarine circulation affected by density flow and wind driven current. The residual current plays an improtant role of material transportation in th bay.

• 한국대기환경학회지
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• 제20권6호
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• pp.729-738
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• 2004

Seasonal variation of major inorganic ions in the greater Seoul area was estimated using a photochemical box model and a gas/aerosol equilibrium model with emphasis on semi -volatile nitrate. Pollutant emission was determined by season by comparing the predicted concentration with the measurement one obtained for a year from the late 1996. The results showed that particulate nitrate was the highest in summer but about 40% of total nitrate was present in the gas phase. This was due to volatilization at high temperature since ammonia was sufficient to neutralize all nitrate regardless of season. As relative humidity in summer was higher than the deliquescence point, particulate ion concentration with water was two times higher than that in other season. So called ‘NOx disbenefit’ indicating increase in particulate ion concentration with decrease in NOx emission was evident especially in winter.