• 한국환경보건학회지
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• 제38권2호
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• pp.118-127
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• 2012

Objectives: This study was undertaken to assess the sanitary conditions in the kitchens of food court/cafeterias and determine seasonal variations. Methods: We measured environmental factors (air temperature, relative humidity, illumination intensity, noise level), and dropping airborne microbes (bacteria and fungi) in the kitchens of eight food court/cafeterias in four seasons (January, April, July, and October). Air temperature and relative humidity were measured with in/out thermo-hygrometers at 1.2-1.5 m above floor level. Illuminance measurement was performed through the multiple point method of Korean Standards (KS). Noise level was measured by the standard methods for the examination of environmental pollution (noise and vibration) of Korea. The estimation of dropping airborne bacteria and fungi was performed through use of Koch's method. Results: The highest kitchen air temperature was in July, and the lowest in January. The average temperature surpassed $21^{\circ}C$ throughout the seasons, suggesting a higher temperature than required for the safe handling of food. Humidity in all the kitchens was measured in the range of 50-60%. Half of the kitchens showed illumination intensities below 300 Lux in April. It was found that the sound pressure level of noise in almost all of the kitchens was higher than 85 dB (A). The highest levels of dropping airborne bacteria and fungi were noted in July. The numbers of airborne bacteria were higher than those of fungi. The levels of dropping airborne bacteria and fungi were affected by air temperature, relative humidity, season, and place. Conclusions: This study indicates that the kitchen environments were unqualified to supply safe food. The hygiene level of the kitchens should be improved.

• 해양환경안전학회지
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• 제15권3호
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• pp.173-177
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• 2009

진동만 잘피밭에서 서식하는 대형 부착해조류는 총 3종이었으며, 출현종은 갈조류의 Scytosiphon lomentaria, Colpomenia sp., 그리고 홍조류의 Gracilaria sp., 으로 구성되어 있었다. 한편 미세 부착해조류는 Cocconeis scutellum와 Cocconeis placentula가 우점하였다. 잘피에 부착하여 서식하는 부착해조류의 현존량은 계절 변동이 뚜렷하게 나타났다. 대형 부착해조류는 2003년 11월에 3.3 g $DW/m^2$, 미세 부착해조류는 2003년 6월에 43,153 $cells/m^2$를 보이며 가장 높게 나타났다. 다른 해역의 잘피밭(광양만, 동대만 및 앵강만)과 비교해보면, 본 조사해역의 잘피밭에서 서식하는 부착해조류의 종 다양성 및 현존량이 매우 낮게 나타나 특이하였다. 이와 같은 결과는 잘피밭의 물리학적인 환경특성(예를 들면 조류 및 유속), 잘피 자체의 생물학적인 특성, 그리고 수질의 악화에 기인하였다.

• 한국대기환경학회지
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• 제12권5호
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• pp.541-554
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• 1996

A set of 1994 data was analyzed to investigate the characteristics of background surface SO$_{2}$ concentrations at Kosan, Cheju Island, Korea. The SO$_{2}$ concentrations at Kosan site show a seasonal variation with a minimum(0.46 ppb) in summer, maximum(1.02 ppb) in spring and an annual mean of 0.83 ppb. These values were 4-7 times higher than those measured in other remote areas, such as Bermuda and Oki Island, but they were similar to the baseline concentrations of other sites in the world. The diurnal variation of SO$_{2}$ concentrations was very small and it shows a peak at 10 am in spring and fall, 2 pm in summer, and 1 pm in winter, respectively. Correlations between local meteorological parameters and SO$_{2}$ concentrations were mot significant. This suggests that the variations of the Kosan's SO$_{2}$ comcentrations were relatively independent on local meteorological variables. Backward trajectory analysis results showed that the seasonal variation of the OS$_{2}$ concentration was mainly due to the inflow of air masses from the continent in spring and from the Pacific Ocean im summer. The results also revealed that the air masses with the highest SO$_{2}$ concentration came through China or the Korea peninsula in spring and through Japan during summer. It was found that the SO$_{2}$ concentrations at Kosan were under the influence of passage of air masses arriving at this site.

• 해양환경안전학회지
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• 제5권2호
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• pp.57-65
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• 1999

The in situ observations and the seawater analyses were conducted at all seasons from July 1996 to April 1999 for the purpose of describing the characteristics of seasonal variations of water quality in Mokpo harbour, Korea. Vertical stratification started to be formed in water column in spring, developed in summer and disappeared in fall. In summer, vertical density distribution of water column was found to be in stable structure with lower temperature and higher salinity of bottom water, and the vertical mixing of water between surface and bottom layers was restricted. In winter, however, surface water was found to be similar to bottom water in temperature and salinity, and water column was in unstable structure and in well-mixed condition between surface and bottom waters. The saturation percentage of dissolved oxygen(DO) in bottom water of inner part of Mokpo harbour at all seasons was shown to be decreased to the third grade or under the third grade of Korean standards of seawater quality. In particular, dissolved oxygen was oversaturated in surface water and undersaturated in bottom water in summer, due to stratification and organic pollution. The difference of DO concentration between surface and bottom waters was found to be greater in spring and summer than in fall and winter, due to stratification and photosynthesis of phytoplankton. The concentrations of chemical oxygen demand(COD) over the entire waters of Mokpo harbour were found to fluctuate from below the third grade to the first grade of Korean standards through all seasons and COD concentrations of same seasons were shown to be different year after year. In particular, in view of COD, the annual average seawater quality of Mokpo harbour was evaluated to be in third grade of Korean standards, due to organic pollution. The average COD of surface water was greater than that of bottom water in spring and summer, due to the autochthonous COD caused by production of phytoplankton in surface waters, while the average COD of surface water was similar to that of bottom water in fall and winter, due to the vertical mixing of water between surface and bottom layers.

• Journal of Yeungnam Medical Science
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• 제30권2호
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• pp.95-100
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• 2013

Background: This study was performed to investigate the epidemiologic and clinical features of acute respiratory viral infection in hospitalized children. Methods: From 2010 to 2012, we tested nasopharyngeal swab specimen in 1,584 hospitalized children with multiple real-time polymerase chain reactions to identify 10 kinds of respiratory viruses (including influenza virus A, B (FluA, FluB), respiratory syncytial virus (RSV), human metapneumovirus (MPV), adenovirus (AdV), human coronavirus (CoronaV), human enterovirus (HEV), human bocavirus (HBoV), parainfluenza virus (PIV), and human rhinovirus (Rhinovirus)). We analyzed the positive rate, annual and seasonal variations, and clinical features (respiratory tract and non-respiratory tract) according to the retrospective review of medical records. Results: Respiratory viruses were detected from 678 (42.8%) of 1,584 patients. The most common detected virus was RSV (35.0%), and then AdV (19.0%), HEV (18.1%). The critical period of the respiratory viral infection was during the first 12 months of a child's life. PIV increased by 8.4%, 12.1%, and 21.1% annually. Bronchiolitis was most frequently caused by RSV, and croup was frequently caused by PIV. The most common cause of meningitis was HEV. Hepatitis-associated respiratory virus was developed 111 in 678 cases. Conclusion: Although this study was confined to a single medical center for three years, we identified the epidemiology and clinical feature of respiratory viruses in Daegu from 2010 to 2012. Future surveillance will be necessary for annual and seasonal variations.

• 한국대기환경학회지
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• 제24권4호
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• pp.470-482
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• 2008

Seasonal variations of chemical composition and optical properties of aerosols at Seoul and Gosan were investigated using the ground-based aerosol measurements and an optical model calculation. The mass fraction of elemental carbon was $8{\sim}17%$, but its contribution on light absorption was high up to $29{\sim}48%$ in Seoul. In Gosan, the contribution of water soluble aerosols on aerosol extinction was $83{\sim}94%$ due to the high mass fraction of these particles in the range of $56{\sim}88%$. Model calculation showed that the water holding capacity of aerosols was larger in Gosan than in Seoul because of higher relative humidity and temperature along with abundant water soluble aerosols. Difference between measured and calculated aerosol optical depths was the highest in summer. This was because aerosol optical depth calculated from ground-based measurements could not consider aerosol loadings at high altitude in spite of high column-integrated aerosol loadings observed by Sun photometer. Although hygroscopic growth was expected to be dominant in summer, the mass concentration of water soluble aerosols was too low to permit this growth.

• 한국환경과학회지
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• 제21권11호
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• pp.1407-1418
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• 2012

The purpose of this study is to analyze seasonal variations of seaweed community structure according to ocean environment at three areas in the east coast of Korea. Mean water temperatures of Gosung, Samchuk, and Gyeongju were $8.3^{\circ}C$, $11.2^{\circ}C$, and $13.1^{\circ}C$, respectively, during the growing winter season of 2011. Subtidal benthic macroalgal flora and community structure were investigated at the sites between February to November 2011. The numbers of seaweed species at the areas were 38, 12, and 15, respectively. The amounts of biomass were 7.35 kg $m^{-2}$, 1.80 kg $m^{-2}$, and 0.84 kg $m^{-2}$, respectively, during the period. The values of C/P, R/P, and (R+C)/P representing flora characteristics at Sokcho area were 0.1, 1.1, and 1.2, respectively. The values of flora characteristics at Samchuk were 0.3, 0.6, and 1.0, respectively. The values of flora characteristics at Gyeongju were 0.4, 4.0, and 1.2, respectively.

• 한국환경과학회지
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• 제20권8호
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• pp.963-975
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• 2011

For this research, they were monitored $CO_2$ flux and environmental factors ($CO_2$ concentration, soil temperature, soil moisture, soil organic carbon, soil pH, soil Eh) in foreshore, paddy field and woods sites at the winter season (January 2009) and the summer season (September 2009). Seasonal and spatial variations for monitored data were analyzed, and linear regression functions of $CO_2$ flux as environmental factors were estimated. $CO_2$ fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the winter season were shown $-8\;mgCO_2m^{-2}hr^{-1}$ and $-25\;mgCO_2m^{-2}hr^{-1}$, respectively. $CO_2$ fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the summer season were shown $47\;mgCO_2m^{-2}hr^{-1}$ and $117\;mgCO_2m^{-2}hr^{-1}$, respectively. Thus, $CO_2$ was sunk from atmosphere to surface at the winter season and it was emitted from surface to atmosphere at the summer season. $CO_2$ fluxes in woods site were emitted $145\;mgCO_2m^{-2}hr^{-1}$ at the winter season and $279\;mgCO_2m^{-2}hr^{-1}$ at the summer season.

• 한국어류학회지
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• 제10권1호
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• pp.11-23
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• 1998

1989년 5월부터 1990년 4월까지 매월 남해도 연안해역에서 소형 otter trawl을 이용하여 어류를 채집하여 종조성 및 계절 변동을 분석하였다. 조사기간 동안 총 64종의 어류가 채집되었다. 줄망둑(Acentrogobius pflaumii), 도화망둑(Chaeturichthys hexanema), 수염문절(Chaeturichthys sciistius), 청멸(Thryssa kammalensis), 실양태(Repomucenus valenciennei)가 많이 채집되었는데, 이들은 전체 개체수의 66.5%, 그리고 생체량의 34.9%를 차지하였다. 그 다음으로 주둥치(Leiognathus nuchalis), 붕장어(Conger myriaster), 병어(Pampus echinogaster), 참서대(Cynoglossus joyneri), 민태(Johnius grypotus), 칠서대(Cynoglossus interruptus), 열동가리돔(Apogon lineatus), 보구치(Argyrosomus argentatus), 밴댕이(Sardinella zunasi) 순으로 채집되었다. 본 조사해역에서 채집된 어류는 대부분이 체장 10cm 이하의 소형 어종이거나 대형 어종의 유어들로 구성되어 있었다. 남해도 연안해역의 어류 군집은 뚜렷한 계절 변동을 보였는데, 채집 어종수는 10 ~1월사이에 많았으며, 2~3월에 적었다. 채집 개체수 및 생체량은 4월과 9월에 높은 값을 보였으며, 수온이 낮은 2~3월에는 채집 어종수, 개체수 및 생체량 모두 낮은 값을 보였다.

• 한국물환경학회지
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• 제25권3호
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• pp.452-458
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• 2009

This study was carried out to assess the effect of discharge loading at sewage treatment plants (STP) on water quality in Kyoungan stream. The seasonal variations of water quality (BOD, COD, SS, TN, and chl.a) at site 1(Mesanribo) were similar with those at site 2(Sehabo). BOD, COD, SS, and chl.a concentration were also similar except for TN and TP concentration which were lower than those at site 1. The BOD, COD, TN, TP and chl.a concentration at site 2 in dry period were higher than that of wet period. The ratios of BOD, TP, COD, SS discharge loading at all STP in Kyoungan stream watershed to delivery loading at site 2 were 0.69, 0.54, 0.48, 0.31, and 0.26 on average, respectively. Both site 1 and site 2, the seasonal variations of discharge loading at STP did not showed any relationship with those of water quality. The mean ratios of inflow loading at site 1 to delivery loading at site 2 were relatively high that ranged from 0.43 to 0.61. In dry period, the ratios of discharge loading at STP in Sehabo watershed to delivery loading at site 2 were below 0.2 except for BOD (0.24), and decreased <0.1 in wet period. While, SS loading from watershed between site 1 and site 2 to delivery loading at site 2 ratios increased in wet period.