• 한국수산과학회지
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• 제46권6호
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• pp.948-956
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• 2013

Seasonal variations in species composition and abundance of the fish assemblages in the coastal waters off Gadeok-do were determined using monthly sample collection by a small otter trawl in 2010-2011. Of a total of 65 fishes collected, the dominant species were Leiognathus nuchalis, Clupea pallasii, Thryssa kammalensis, Engraulis japonicus, Repomucenus valenciennei, Sillago japonica, Trachurus japonicus, Pennahia argentatus, Okamejei kenojei, Cynoglossus joyneri, Pholis fangi, Pleuronectes yokohamae, and Zoarces gillii. These 13 fishes accounted for 92.8% of the total number of individuals collected. The number of fish species, number of individuals, biomass, and species diversity indices fluctuated with the seasons. The peak number of fishes occurred in April, whereas the biomass of fishes was highest in August. The numbers and biomass of fishes were lower in February corresponding with the low temperatures, and diversity indices were lower in January than in any other month.

• 상하수도학회지
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• 제26권1호
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• pp.131-139
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• 2012

Field experiment was performed from June 2010 to July 2011 to evaluate pollutants removal efficiency in the constructed wetland system for the treated wastewater and the river water. The wetland systems were constructed near Gyungan river. Two different systems with meandering shape were compared for seasonal base and operational period base. Several kinds of aquaculture are planted through the corridor of wetland system. Average removal rate of BOD, T-N and T-P for A system were 15.8%, 14.8% and 26.5%, respectively. Average removal rate of BOD, T-N and T-P for C system were 23.5%, 27.8% and 10.6%, respectively. The effluent from two wetland systems often exceeded effluent water quality standards for wastewater influent, however effluent water quality standards for river water. However, the wetland system can be useful to treat polluted river water and effluent from wastewater plant. Removal rate of pollutants in seasonal variation was the highest in summer for BOD and T-N, however the removal rates of T-P were higher in spring and autumn than in summer.

• 수산해양교육연구
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• 제29권1호
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• pp.257-269
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• 2017

The occurrence variations of decapods by season and depth off Oryuk Islets, Busan were investigated at seven stations in April and October 2009, July 2010 and January 2011. Decapods were collected by SCUBA diving at 5 m and 10 m depths. 46 species belonging to 18 families in 3 orders were identified. Pilumnus minutus, Pugettia intermedia, Pachycheles stevensii, and Paguristes japonicus were dominant species, comprising 73.0% of total decapods. P. minutus and P. intermedia were abundant in all seasons (except summer) while P. stevensii and P. japonicus were abundant in fall and summer. Dominant species were divided into three groups (resident species, seasonal species and temporary species) on the basis of their occurrence patterns. P. minutus and P. intermedia were resident species while P. stevensii, P. japonicus were temporary species. The species number, density and biomass of decapods were fluctuated by seasons. They were highest in fall and lowest in winter. This study implied that the variations of species number and density of decapods were significantly related with seasonal change of water temperature.

• 한국식품영양과학회지
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• 제27권4호
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• pp.775-784
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• 1998

This study was conduced to investigate the seasonal variation of dietary intake and quality obtained by 24 hour recall method in Korean adults living in rural area. The mean daily intakes of 4 seasons were 1,692kcal for energy, 63g(14.8% of energy) for protein, 30g(15.7% of energy) for fat, 257g(60.7% of energy) for carbohydrate. Mean daily intakes were significantly highest in winter for most of the nutrients, and lower in summer for energy, fat, calcium, iron. Mena adequacy ratio(MAR), an index of overall nutritional quality was 0.65 in winter, 0.67 in spring, 0.65 in summer and 0.72 in autumn and nutrient adequacy ratio(NAR) was significantly different fro vitamin C agmong different seasons. Subjects consumed usually 15.3 different foods in winter, 14.5 in summer, 13.9 in spring and 13.7 in autumn. The number of food consumed was positively correlated with intake of most nutrients, especially in autumn. For variety among the five major food groups(grain, meat, dairy, fruit, vegetable) with a dietary diversity scores(DDS) calculated, the average socre of DDS was 3 in all seasons and omitted food groups were usually dariy and fruit. In conclusion, dietary intake and quality of Korean adults were different according to seasons.

• 한국환경보건학회지
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• 제26권2호
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• pp.41-48
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• 2000

This study has been carried out to determine the seasonal characteristics of concentration of various ionic (CI-, NO3-, SO42-, Na+, NH+, K+, Ca2+) and heavy metallic (Pb, Mn, Cu, Ni) species in Pusan from August 1997 to April 1998. The concentrations of CI-, Na+, K+ were higher during summer with 2.98 ${\mu}{\textrm}{m}$/㎥. Seasonal variation of total concentration of but the concentration of NH4+ was higher during winter with 2.46${\mu}{\textrm}{m}$/㎥. Seasonal variation of total concentration of heavy metals(Pb, Cu, Mn, Ni) were 186.0 ng/㎥ in summer, 222.6 ng/㎥ in autumn, and 135.83 ng/㎥ in winter. Over the seasons inspected, the concentration of Mn was higher in coarse particles than fine particles and concentration of Ni was higher in fine particles than coarse particles. during yellow sand period, the concentration of TSP was increased about two times than that of other period. SO42-, Ca2+ concentrations were higher than other ionic components because of soil particles. The concentration of Ni showed 94.62ng/㎥ was increased about 4~5 times than other period. Principal component of the yellow sand, SO42-, Ca2+ could be discreased by rainfall and washout effect of atmospheric aerosol was higher in coarse particles than fine particles. Results from PCA(principal component analysis) showed that major pollutant was NaCl by seasalt particulate and (NH4)2SO4.

• 대한원격탐사학회지
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• 제24권1호
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• pp.79-89
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• 2008

Irregular temporal sampling is a common feature of geophysical and biological time series in remote sensing. This study proposes an on-line system for reconstructing observation image series contaminated by noises resulted from mechanical problems or sensing environmental condition. There is also a high likelihood that during the data acquisition periods the target site corresponding to any given pixel may be covered by fog or cloud, thereby resulting in bad or missing observation. The surface parameters associated with the land are usually dependent on the climate, and many physical processes that are displayed in the image sensed from the land then exhibit temporal variation with seasonal periodicity. A feedback system proposed in this study reconstructs a sequence of images remotely sensed from the land surface having the physical processes with seasonal periodicity. The harmonic model is used to track seasonal variation through time, and a Gibbs random field (GRF) is used to represent the spatial dependency of digital image processes. The experimental results of this simulation study show the potentiality of the proposed system to reconstruct the image series observed by imperfect sensing technology from the environment which are frequently influenced by bad weather. This study provides fundamental information on the elements of the proposed system for right usage in application.

• Environmental Engineering Research
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• 제24권3호
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• pp.501-512
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• 2019

The seasonal effects on the biostability of drinking water were investigated by comparing the seasonal variation of assimilable organic carbon (AOC) in full-scale water treatment process and adsorption of AOC by three filling materials in lab-scale column test. In full-scale, pre-chlorination and ozonation significantly increase $AOC_{P17\;(Pseudomonas\;fluorescens\;P17)}$ and $AOC_{NOX\;(Aquaspirillum\;sp.\;NOX)}$, respectively. AOC formation by oxidation could increase with temperature, but the increased AOC could affect the biostability of the following processes more significantly in winter than in warm seasons due to the low biodegradation in the pipes and the processes at low temperature. $AOC_{P17}$ was mainly removed by coagulation-sedimentation process, especially in cold season. Rapid filtration could effectively remove AOC only during warm seasons by primarily biodegradation, but biological activated carbon filtration could remove AOC in all seasons by biodegradation during warm season and by adsorption and bio-regeneration during cold season. The adsorption by granular activated carbon and anthracite showed inverse relationship with water temperature. The advanced treatment can contribute to enhance the biostability in the distribution system by reducing AOC formation potential and helping to maintain stable residual chlorine after post-chlorination.

• 수산해양기술연구
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• 제59권1호
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• pp.9-18
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• 2023

Fish samples were collected by a set net from April to December 2020 at the coastal waters off Tongyeong, Korea to determine fish species composition and seasonal variation. A total of 330,675 fish (1,032,578 g) representing 56 species belonging to 39 families were collected during the sampling period. The dominant species were Engraulis japonicus, Trachurus japonicus and Trichiurus japonicus, which accounted for 98.1% of the total number of individuals and 87.5% of the total biomass collected. E. japonicus and Chelidonichthys spinosus appeared every month off the coast of the Tongyeong. Cluster analysis based on the number of individuals of fish were classified into two groups at the dissimilarity level of 57%, and the results of ANOSIM analysis revealed significant differences in community structure among the two groups.

• 환경생물
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• 제18권1호
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• pp.21-31
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• 2000

We investigated seasonal variation of microalgal assemblages, sea water temperature, salinity and suspended solid and the parameters measured daily from January 1998 to October 1999 at a nearshore shallow-water in Marian Cove, Maxwell Bay, King George Island, the Antarctic. Annual mean surface water temperature was -0.3$0^{\circ}C$ and the highest water temperature was 4.53$^{\circ}C$ (22 January 1999) and the lowest water temperature was -2.07$^{\circ}C$ (23 August 1998). Annual mean salinity was 33.38 psu, ranging from 42.80 psu (6 January 1999) to 19.50 psu (6 June 1999). Annual mean suspended solid (SS) during two years was 34.14 mgㆍ1$^{-1}$, ranging from 60.62 mgㆍ1$^{-1}$(7 March 1998) to 12.90 mgㆍ1$^{-1}$ (26 December 1998). Chlorophyll $\alpha$ (Chl $\alpha$) concentrations were measured in order to know seasonal variations of microalgae in the surface seawater. Annual mean of total Chl a concentration was 0.55$\mu\textrm{g}$ㆍ1$^{-1}$, the highest Chl $\alpha$ concentration (12.16$\mu\textrm{g}$ㆍ1$^{-1}$) appeared in 4 October 1998, the lowest Chl $\alpha$ concentration appeared 0.19$\mu\textrm{g}$ㆍ1$^{-1}$, Monthly mean total Chl $\alpha$ concentration was high in October 1998 (1.32$\mu\textrm{g}$ㆍ1$^{-1}$) and low in July on 1998 (0.28$\mu\textrm{g}$ㆍ1$^{-1}$). Annual mean nano-sized Chl $\alpha$ concentration was 0.40$\mu\textrm{g}$ㆍ1$^{-1}$, monthly mean nano -sized Chl $\alpha$ concentration was high in November 1998 (0.90$\mu\textrm{g}$ㆍ1$^{-1}$), and low in July 1999 (0.22$\mu\textrm{g}$ㆍ1$^{-1}$). Annual mean micro-sized Chl $\alpha$ concentration was 0.15$\mu\textrm{g}$ㆍ1$^{-1}$ monthly mean micro-sized Chl $\alpha$ concentration was high in October 1998 (0.81$\mu\textrm{g}$ㆍ1$^{-1}$), and low July 1998, January, February and September 1999 (0.05$\mu\textrm{g}$ㆍ1$^{-1}$). More than 65% of total Chl $\alpha$ was concentrated during spring and summer time between October and March. Microalgal variation appeared to be due to physical factors of seawater in the Antarctic nearshore from 1998 to 1999. The reason why micro-sized Chl $\alpha$ did not increase during austral summer was the bay had been frozen by decrease of water temperature. We think that total microalgal abundance was decreased because the summer microalgal abundance was determined by variation of water temperature during winter season. [Chl $\alpha$ concentration, Microalgal assembalges, Seasonal variation, the Antarctic nearshore].

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2017년도 공동학술발표회
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• pp.189-189
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• 2017