• 한국수산과학회지
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• 제43권6호
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• pp.614-622
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• 2010

The sanitary quality of a shellfish-growing area in Gangjinman, Korea, was assessed through a bacteriological examination of seawater form January 2007 to December 2009. The range of the geometric mean (GM) and the estimated 90th percentile for most-probable-number (MPN) values for fecal coliforms in samples collected in the designated area were 2.0-2.4 and 6.1-11.5 MPN/100 mL, respectively. Therefore, the bacteriological quality of seawater in the designated area in the Gangjinman area met the National Shellfish Sanitation Program (NSSP, USA) guidelines for approved areas. Also, the sanitary status of shellfish harvested from the designated area met the Korean Shellfish Sanitation Program (KSSP) fecal coliform criterion (<230 MPN/100 g). However, the degree of bacteriological contamination increased rapidly, and water quality exceeded the criteria for approved areas when large amounts of rain fell before the sampling date. Fortunately, fecal pollutants did not affect the bacteriological quality of a buffer zone established between the shoreline and the designated area. These results indicate that the current buffer zone established around the designated area protects the designated area properly.

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.611-615
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• 2007

The purpose of this study was to evaluate the immunogenicity and safety of Salmonella Typhi Vi capsular polysaccharide vaccine (Vi vaccine) in Korea. The immunogenicity of a single dose of Vi vaccine was evaluated in 157 subjects (75 children and 82 adults) before and at 1, 6, and 12 months after vaccination. Immunogenicity was measured with a passive hemagglutination assay (PHA), quantified as geometric mean titers (GMTs) and seroconversion rates. The safety of the vaccine was investigated by determining adverse reactions occurring within 4h, 3 days, and 1 month after injection. The seroconversion rate for children and adults 1 month after vaccination was 96.92% and 89.02%, respectively. In the case of children, the GMTs of Vi antibodies before vaccination were $5.87{\pm}1.34\;and\;142.59{\pm}2.39$ at one month after vaccination. For adults, the GMTs before and one month after vaccination were $5.58{\pm}1.28\;and\;58.56{\pm}3.67$, respectively. Vi antibodies persisted for as long as 6 and 12 months after vaccination. All adverse reactions in adults and children were minor and did not require treatment. The Vi CPS vaccine was safe and immunogenic in adults and children older than 5 years.

• 한국수산과학회지
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• 제52권6호
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• pp.605-616
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• 2019

This study evaluated the abundance and antimicrobial resistance of Escherichia coli in oysters Crassostrea gigas and major inland pollution sources sampled in 2014-2015 from Jaranman-Saryangdo on the southern coast of Korea. The ranges of the geometric mean of E. coli concentrations in oysters and major inland pollution sources were <20-29.8 MPN/100 g and 7.5-137.2 MPN/100 g, respectively. We isolated 247 strains of E. coli (28 from oysters and 247 from major inland pollution sources) and examined the antimicrobial resistance patterns of all isolates. Isolates from both sources were highly resistant to rifampin (99.5-100%) and cephalothin (70.8-78.6%). The resistance rate was higher in E. coli isolated from oysters those from inland pollution sources. Multiple resistance against at least four antimicrobials was observed in 85.7% and 21.0% of the oyster and major inland pollution sources isolates, respectively.

• 한국연초학회지
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• 제28권1호
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• pp.58-66
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• 2006

Threshold limit value (TLV) test between expert and consumer panel was conducted about absolute, recognition and difference threshold respectively. And we tried to suggest appropriate and minimum acceptable menthol concentration level by consumer panel. Determination of threshold value was based on ASTM E 679-79 method by forced-choice ascending concentration series. In addition, a semi-ascending paired difference method was referred to conduct test. The group threshold value was determined as the value of geometric mean individual threshold. The smokers were dividend by two groups, trained and consumer panel. Trained panel was selected according to sensitivity to menthol discrimination. Consumer panel wasrecruited in proportion as population ratios including female smokers. They were all over twenty years old volunteers and summed up thirty four persons. In terms of sensor evaluation, overall difference test with seven-category scale by both trained and consumer panelists were done. On judging correct or incorrect answer, two by three cut-off levels applied to. Every test was conducted with two sessions, before smoking and during smoking period. And, only two samples served each paneI per test with regard to sensory fatigue and reliable results. All tests were replicated, and in total 32 times per panelist. In conclusion, the recognition threshold about consumer and expert panel was 358 ppm/cig. and 276 ppm/cig. in separately. Besides, absolute and difference thresholds were obtained also. And, we conduct difference threshold test with two different ways, upward and downward. And, The results of each method were 246, 195 ppm/cig., 1414, 1336 ppm/cig. and 1047, 972 ppm/cig.

• 한국산업보건학회지
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• 제22권4호
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• pp.265-275
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• 2012

Objectives: The aim of this study was to investigate the distribution patterns and exposure concentrations of biological hazards in waste handling industries. Methods: We selected 3 recyclable waste sorting plants(RWS), 2 food recycling plants(FR), 1 landfill area(LA) and 1 waste incineration plant(WI). Total airborne bacteria and fungi were measured with single stage impactor and gelatin filters. Endotoxin and glucan were measured with polycarbonate filters in total and respirable dust. Results: The geometric mean of airborne bacterial concentration was the highest in FR($3,273CFU/m^3$), followed by LA, RWS, and WI as 1,334, 934, and $860CFU/m^3$. The fungal concentrations were 6,031, 5,052, 3,307, and $713CFU/m^3$ in RWS, WI, FR, and LA, respectively. By process, WI pit showed the highest concentrations of bacteria, fungi, and endotoxin, followed by inside of bulldozer in LA. The indoor to outdoor ratios of bacteria, fungi, endotoxin and glucan were 2.3, 4.0, 2.3, and 5.0 in RWS, 29.5, 4.9, 7.6, and 5.0 in FR, 5.3, 8.7, 26.8, and 9.5 in WI, respectively. Conclusions: We found that biological hazards, specifically bacteria in FR, fungi in RWS and endotoxin in WI pit and bulldozer at LA, should be controlled to prevent worker's respiratory diseases.

• 한국산업보건학회지
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• 제22권4호
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• pp.284-292
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• 2012

Objectives: The objective of this study was to investigate the relations between the bacterial concentration and the environmental factors in the water soluble metal working fluids at factories. Methods: The bacterial concentrations for airborne and fluid samples of 7 factories were quantified during the summer season. And we statistically analysed the relations between the bacterial concentrations and the factors such as temperature, relative humidity, usage quantity, mixing ratio and exchange interval. Results: The geometric mean levels of the airborne bacterial concentrations were 79.1(range : N.D.~686) $CFU/m^{3}$ and 68.1(range: N.D.~919) $CFU/m^{3}$ in the process and outdoor. The airborne bacterial concentrations showed no statistical difference by process, usage quantity, mixing ratio and exchange interval. The airborne bacterial concentrations had negatively weak correlations with air temperature and relative air humidity(p<0.05). The bacterial concentrations and pH showed significantly negative correlations in the fluids(p<0.05). And the airborne bacterial concentrations in factories and those in metal working fluids showed no statistical relationship. Conclusions: In the water soluble metal working fluids using factories, the airborne bacterial concentrations of the process were related to those of the outdoor and environmental factors, rather than the onsite contaminated metal working fluids.

• 한국측량학회지
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• 제34권4호
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• pp.391-402
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• 2016

Among the various remote sensing sensors compared to the electro-optical sensors, SAR (Synthetic Aperture Radar) is very suitable for assessing damaged areas induced by disaster events owing to its all-weather day and night acquisition capability and sensitivity to geometric variables. The conventional CD (Change Detection) method that uses two-date data is typically used for mapping damage over extensive areas in a short time, but because data from only two dates are used, the information used in the conventional CD is limited. In this paper, we propose a novel CD method that is extended to use data consisting of two pre-disaster SAR data and one post-disaster SAR data. The proposed CD method detects changes by using a similarity weight image derived from the neighborhood information of a pixel in the data from the three dates. We conducted an experiment using three single polarization ALOS PALSAR (Advanced Land Observing Satellite/Phased Array Type L-Band) data collected over Miyagi, Japan which was seriously damaged by the 2011 east Japan tsunami. The results demonstrated that the mapping accuracy for damaged areas can be improved by about 26% with an increase of the g-mean compared to the conventional CD method. These improved results prove the performance of our proposed CD method and show that the proposed CD method is more suitable than the conventional CD method for detecting damaged areas induced by disaster.

• 한국도로학회논문집
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• 제17권5호
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• pp.47-56
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• 2015

PURPOSES: The purpose of this study is to estimate the impact of variable message signage (VMS) on traffic safety as a function of road curve radius using statistical methods. METHODS: In order to analyze the impact of VMS installations on traffic safety, travel speed, lateral distance, and geometric data relating to road curvature in each study area was acquired and analyzed for the impact of providing VMS information on driver performance and traffic safety using statistical methods including student t-test, Mann-Whitney test, and the Anderson-Darling test for estimating traffic safety hazard zone in each lane. RESULTS: As a result of analyzing driver performance characteristics before and after providing VMS information, it was determined that by providing VMS information, mean travel speed is deceased and vehicles are driven with increased precision, following the centerline in the first and second lanes. Also the results of analyzing traffic safety impacts of VMS indicate that traffic safety performance factors in the first lane of the Gapyeong section can, on average, increase in the left and right side of the lane by 19.22% and 68.98%, respectively, and in the case of the second lane, safety impacts, on average, can increase in both sides by 100%. For the Hongcheon section, traffic safety impacts in the first lane, on average, can increase along the left and right sides of the lane by 32.31% and 47.18%, and within the second lane, traffic safety can be increased along the left and right side of the lane by 10.97% and -0.01%, respectively. CONCLUSIONS: Based on the results of this study, the impact on traffic safety obtained by providing VMS information for road sections with smaller curve radii is greater than can be obtained for road sections with larger curve radii.

• 한국강구조학회 논문집
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• 제16권5호통권72호
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• pp.653-660
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• 2004

도심지의 토지 이용률을 높이기 위하여 상대적으로 단면이 작은 원형 강교각의 건설이 요구되고 있다. 이때 줄어든 단면으로 인해 감소된 좌굴내하력을 높이는 방안으로 수직보강재의 적용을 고려할 수 있다. 그러나 수직보강재를 적용함으로써 얻어질 수 있는 좌굴내하력의 증가효과는 아직 명확하지 않다. 본 연구에서는 기하학적, 재료학적 비선형을 고려한 탄소성 유한요소해석을 수행하여 원형강교각의 반지름-두께비에 따른 수직보강재의 수가 좌굴내하력에 미치는 영향을 명확히 하였다. 또한, 수직보강재의 폭과 두께, 원형강교각의 세장비에 따른 좌굴해석을 수행하여 그 관계를 명확히 하였다.

• 한국방사선학회논문지
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• 제9권3호
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• pp.139-145
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• 2015

SPECT를 이용한 환자의 검사 시 몸 안에서 방출되는 ${\gamma}$-선은 감쇠 또는 산란 등의 현상이 일어나며, 검출기에 도달할 때 조준기의 물리적 특성과 기학적인 모양에 따라 퍼지는 현상이 발생하여 정량분석이 불가능하였다. 체내에서 방출되는 ${\gamma}$-선의 정확한 정량분석을 위해서는 반드시 부분용적효과에 대한 보정이 고려되어야 한다. 본 논문에서는 SPECT의 종합적인 부분용적효과를 해결하기 위하여 Sinogram Filter를 구현하였다. 구현된 Filter를 적용하여 실험을 한 결과, SPECT에서 발생되는 부분용적효과를 제거하였다. 기존방법과 제안한 방법을 비교하기 위하여 PSNR을 시행한 결과 제안한 방법으로 한 경우 PSNR은 7 dB, 기존방법은 14 dB로 나왔다. 제안한 방법의 dB이 낮아진 이유는 산란선 제거를 많이 하여 MSE가 높아지기 때문에 PSNR값이 낮게 나타났다. 따라서 제안한 방법을 적용한다면 SPECT 영상의 부분용적효과를 제거하여 영상의 질이 좋아질 것이다.