• Korean Journal of Environmental Biology
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• v.17 no.2
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• pp.159-168
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• 1999

The ophemeropterans such as Epeorus pellucidus, Uracanthella rufa and Drunella uculea were dominated in station 1. It was generally showed the stable aquatic communities with low dominance index values throughout the year in station 2. The first dominant species in station 3 were all mayflies with the average DI value of 0.38. The first dominant species of Uracanthella rufa known as relatively tolerant species in station 4. A crustacean species Gammarus spp. have frequently occurred as the 1st or 2nd dominant species in station 5. Limnodrilus socialis, and Chironomus spp. were dominated in stations 6 and 7 Station 1, 2 and 3 were classified as oligosaprobic status according to their average diversity index values ranging from 3.46 to 3.52. Station 7 showed $\alpha$-mesosaprobic water condition with the overall average diversity value of 1.26. In general, the equitability and species richness values in the same sampling areas had close relations with their diversity values. The dendrogram drawn by dissimilarity values among 7 sampling sites indicates that the macrobenthic communities were divided into 3 groups： stations 1, 2, 3 and 4； stations 6 and 7； and station 5 alone.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.245-248
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• 2004

다대포 갯벌의 YP는 0.06~0.13 mg/L이었고 진우도의 TP는 0.06~0.11 mg/L로 조사시기별로는 두 조사지역간 차이는 없었고 TN은 다대포의 경우 1.44~2.87 mg/L, 진우도는 0.15~1.09 mg/L로 조사되어 매 조사시기마다 진우도보다는 다대포에서 월등히 높았으며 두 지역 모두 해역의 어염등급에 비추어볼 때 상당히 오염이 진행된 상태였다. 조사된 미세조류는 Navicula, Nitzschia, Cyclotella, Cymbella, Synedra 등 13속 26종류로 호청수성 조은 Achnanthes convergence 등 1속 2종류, 호오염성 종은 Nitzschia palea 등 5속 8종류, 광적응성 종은 Cymbella minuta 등 3속 5종류였으며 매 시기마다 우점을 보인 종은 Nitzschia, Navicula 였다. DAIpo 지수는 다대포의 경우, 평균 31.1 진우도는 평균 48.4로 조사되어 비교적 낮은 DAIpo 값을 보였지만 계절별로는 다대포와 진우도의 경우 모두 봄인 5월에 가장 높은 DAIpo 값으로 비슷한 경향을 보였으나 다대포의 경우에서는 매 계절마다 진우도보다 더 DAIpo값이 낮게 조사되었다. DAIpo 값으로부터 갯벌의 오염도를 판정하면 다대포는 $\alpha$-중부수성, 진우도는 $\beta$-중부수성에 해당하여 다대포의 경우가 진우도보다 더 오염이 심한 것으로 조사되었다.

• Journal of the Korean Data and Information Science Society
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• v.27 no.2
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• pp.275-284
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• 2016

Accurate electricity demand forecasts is essential in reducing energy spend and preventing imbalance of the power supply. In forcasting electricity demand, we considered double seasonal Holt-Winters model and TBATS model with sliding window. We selected a specific time zone as the reference line of daily electric demand because it is least likely to be influenced by external factors. The forecasting performance have been evaluated in terms of RMSE and MAPE criteria. We used the observations ranging January 4, 2009 to December 31 for testing data. For validation data, the records has been used between January 1, 2012 and December 29, 2012.

• Korean Journal of Ichthyology
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• v.23 no.1
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• pp.37-45
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• 2011

Seasonal variation in species composition and abundance of fish larvae assemblages in the south-western Jinhae Bay were investigated monthly in 2009. During the study period, 49 larvae species belonging to 24 families were collected. The dominant species were Clupea pallasii, Hexagrammos otakii, Konosirus punctatus, Engraulis japonicus, Parablennius yatabei, and Omobranchus elegansei. These six species accounted for 92.7% of the total number of individuals collected. The number of species, number of individuals, and species diversity indices fluctuated with the seasons. The peak number of species and individuals occurred in July and January, respectively. Principal component analysis(PCA) and correlation analysis showed that variation in monthly water temperature could act as an indicator of seasonal variation in community structure and abundance of the dominant species; in particular, those of C. pallasii, H. otakii, E. japonicus and P. yatabei corresponded with the water temperature.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.3
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• pp.309-319
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• 1998

Species composition and seasonal variations of fishes collected by winged stow net on anchors in the coastal water off Namhae Island was studied from May 1989 m April 1990. During the study period, a total of 56 fish species were collected. Engraulis japonicus, Conger myriaster, Trichiurus lepturus, Sardinella zunasi, Ammodytes personatus, and Thryssa kammalensis predominated. These six species accounted for 93.9% of the total number and 81.3% of the total biomass of fishes collected. Fishes collected by winged stow nets on anchors were primarily small fish species or early juveniles of large fish species. Both abundance and species composition of fishes changed with season. Seasonal peaks of number of species occurred in spring and fall, while those of number of individuals and biomass occurred in spring. The lowest number of individuals and biomass were observed in winter. Low species diversity indices were observed in summer. These low diversity indices in summer were mainly due to predominance of E. japonicus which accounted for approximately 90% of all fishes collected. More species and greater biomass were collected during nighttime.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.288-301
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• 2000

The species composition and seasonal variation of fish assemblage in the coastal water off Gadeok-do, Korea were studied using the monthly trawled samlpes through a year of 1998. During the study period, 110 species of fishes from 57 families were collected. Repomucenus valenciennei, Thryssa kammalensis, Leiognathus nuchalis and Zoarces gilli dominated the fish assemblage throughout the year, and were responsible for $ 57.6{\%}$ and $37.2{\%}$ in the number of individuals and biomass, respectively. Fish species of secondary importance in abundance were Sillago japonica, Apogon lineatus, Pholis fangi, Engraulis japonicus, Thryssa adelae, Pho;is nebulosa, Conger myriaster, Liparis tanakai, Acentrogobius pflaumii, Limanda yokohamae, Chaeturichthys hexanema, Erisphex pottii and Cunoglossus abbreviatus. Higher numbers of species were collected in spring and autumn than in summer and winter. Abundance was high in spring and autumn, and low in summer and winter, Species diversity indices showed that the fish assemblage was more diverse in autumn than any other seasons.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.366-379
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• 2002

The monthly collected fish samples by three sides tyke nets were analyzed in order to study species composition and seasonal variation of fish assemblage in the coastal water off Gadeok-do, Korea through a year of 1998, During the study period, a total of 136 fish species of 69 families were collected. Trachums japonicus, Konosims punctatus and Mugil cephaus were three dominant species in the fish assemblage and they accounted for $63.7\%$ and $83.1\%$ in the number of individuals and biomass, respectively. Fish species of secondary importance in abundance were Leiognathus nuchalis, Takifugu niphobles, Somber japonious, Trichiurus lepturus, Chelon affinis, Apogon lineatus, Nibea aibiflora and Acanthopagrus schlegeli. The highest number of species was collected in July and the lowest in february. Abundance was high in spring, and low in winter. Species diversity indices showed that the fish assemblage was less diverse in spring than any other seasons.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.234-243
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• 2006

A total 34 fish species, 1,110 individuals, and 5,107.3 g of fishes were collected by a surf net in the eelgrass bed in Jisepo Bay of Geoje Island, Korea. Samples were monthly collected from March 2005 to February 2006. The dominant fish species were Rudarius ercodes, Ditrema temminckii, Syngnathus schlegeli, Petroscirtes breviceps, which accounted for 73.5% of total number of individuals and 63.6% of biomass of fish collected. The number of species and biomass were low from March 2005 to July 2005, and high from August 2005 to October 2005. Species diversity indices ranged from 0.836 to 2.016, and showed the highest value in December 2005.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.251-265
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• 2006

To investigate the impingement of fish on the traveling screens, fishes were collected from the traveling screens at Hadong Power Plant through the year of 1999. A total of 84 fish species were collected during the study period. The dominant species were Leiognathus nuchalis, Engraulis japonicus, Trichiurus lepturus and Takifugu niphobles. These four species accounted for 78.2% of the total number of individuals and 52.0% of total biomass collected. The number of fish species, number of individuals, biomass and species diversity indices fluctuated with the seasons. The number of species and biomass were high in April and August, and the number of individuals was high in April and July. However, the number of fish species, number of individuals and biomass of fishes showed low values in winter.

• Journal of Life Science
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• v.24 no.5
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• pp.532-542
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• 2014

This study describe seasonal patterns in the variation of phytoplankton frequency in the water surface and basal layers and their spatial distributions at seven stations in Hwadang-ri, Goseng-gun in 2013. The phytoplankton community at Hwadang-ri was very diverse, with 60 taxa identified, representing three classes. Diatoms (Bacillariophyceae) exhibited the greatest diversity, with 41 taxa identified. These were followed by the dinoflagellates Dinophyceae, Cryptophyceae, and Eugenophyceae, with 16 taxa, two taxa, and one taxon, respectively. Water surfaces were shown with the relative individual density or abundance across areas. Except in January, Shannon-Weaver indices of diversity of the water surface layer were lower than those of the basal layer. In addition, evenness indices of the basal layer were higher than those of the water surface layer, except in January. For the community as a whole, the values of ${\beta}$-diversity were low for the seven stations: 1.125 for the water surface layer and 1.481 for the basal layer. Seasonal values for ${\beta}$-diversity were similar at the seven stations: 1.725 for the water surface layer and 1.347 for the basal layer. The phytoplankton community showed high taxonomic homogeneity in all four seasons, in addition to similar trends in seasonal development at depths in the same stations. However, the size distribution of the abundance and biomass showed a statistically significant west-east difference.