• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3617-3619
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• 2012

Background: The completeness of cancer registration is a major validity index of any reported cancer incidence. The present study aimed to evaluate the esophageal cancer incidence registered in the Tehran Metropolitan Area Cancer Registry. Materials and methods: The data on esophageal cancer abstracted from three sources of 1) pathology departments, 2) medical records, and 3) death certificates during 2003 till 2007 were utilized. The completeness of the data sources were evaluated using coverage (defined as the proportion of a community population with esophageal cancer identified by the source) and density (defined as the proportion of non-empty fields of the data by source). Results: A total 1,404 cases of esophageal cancer were reported for the duration of the study. Pathology provided 771, medical records 432, and death certificates 609. The coverage was 0.55 for pathology, 0.31 for medical records, and 0.43 for death certificates. The respective density values were 0.82, 0.96 and 0.98, respectively. Pathology (0.45) was the most complete source followed by medical records (0.42), and death certificates (0.29). Discussion: A low degree of completeness dictates putting more effort into case finding plus abstracting data more thoroughly.

• Journal of the korean society of oceanography
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• 제33권3호
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• pp.64-70
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• 1998

Forty sediment samples from Kyeonggi Bay, Korea were analyzed for butyltins, including tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) to determine their distribution and source in this area. Total butyltin concentrations in Kyeonggi Bay sediments ranged from 0.8 to 297 ng/g dry wt. with a mean value of 38 ng/g. The highest butyltin concentration was found in the innermost site in Incheon Harbor basin. The mouth of Han River had higher butyltin levels in sediments compared to open ocean. Butyltin levels correlated well with organic carbon content of sediment, but the major factor was the distance from the source area where antifouling paints were used for vessels and marine structures. Butyltin concentrations in the study area were lower than those reported for bays in other parts of the world. Considering the high toxic potential and sediment/water partition coefficient of TBT, further studies are needed to assess its biological effect in the marine ecosystem of Kyeonggi Bay.

• 한국환경보건학회지
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• 제28권2호
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• pp.11-22
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• 2002

This study analyzes the river system and water quality conditions of Bukchun in order to establish a basic plan for Preparing a natural learning and experimental area of environmental ecosystem in Bukchun, Gyeongju. It also tries to establish an integrated plan for water management of Bukchun stream based on water contaminants. In addition, after analysing the water quality at 13 points during the non-rainy season, the effluent of municipal wastewater was of relatively better quality with I ~ II grade, below the water quality standard of the river, except in points near Samsung apartments. However, analysing the Hyeongsangang and the effluent of Bomunho and Duckdongdam in rainy season, the water quality was II ~ III grade according to environmental standard. The water Quality of those samples was strongly dependent of non-point source.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.451-454
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• 2003

Nonpoint source pollution of groundwater and subsurface water from irrigated agriculture is a major concern in many areas. In this study we aimed to investigate the effect of the water applied by irrigation in agricultural area on the transport of nitrogen and phosphorus originated from fertilizers applied to the surface of soil in agricultural activities. We first conducted investigation on the resdual concentrations of soil N and P in a selected agricultural area. And simulating the target area by column studies in the laboratory leaching extent of various components from the composite and urea fertilizers applied on the soil surface during irrigation was studied. Infiltration of water enhanced the leaching of nitrogen and phosphorus in both the rice paddy field soil and the patch soil. The downward N and P transport with infiltrating water was more pronounced in the patch soil column and the increased residual concentrations of N and P in the lower sections in the patch soil column was found with time.

• 한국대기환경학회지
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• 제6권2호
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• pp.135-146
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• 1990

The purpose of the study was to identify sources of particulate matters statistically and to estimate the mass contribution quantitatively in the Pusan metropolitan area. Then, the study has used the TTFA (target transformation factor analysis) model, a receptor model, to apportion aerosol mass with the raw data of 106 ambient samples characterized by 24 heavy metal variables. The TTFA was extensively applied to generate source profiles and their aerosol mass contributions. Though a couple of sources were not identified, four to seven sources were able to be extracted at 3 different sites (Jang Rim-Dong, Kwang Bok-Dong, and Kwang An-Dong) in Pusan area and finally mass conributions could be calculated.

• 한국환경과학회지
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• 제11권4호
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• pp.383-389
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• 2002

Odor sources of a chemical plant in Ulsan were surveyed and temperatures, humidities and flow rates of each exhaust gas were measured. The air samples collected from each source were transferred to the laboratory for sensory test and their odor concentrations were investigated. The odor emission rate of each source was estimated from the recorded results and assigned the sources expected to be needed for the odor prevention policy using the simple prediction equation of the affection by malodor to the nearest residential area. From the total odor emission rate of the examined plant and the relation table for expectable affection area it was concluded that total odor emission of this plant might be decreased for the prevention of residential complaint.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.608-611
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• 2000

Large area plasma source becomes important as the substrate size increases. In this work, four inductively coupled plasma(ICP) unit sources are distributed 2${\times}$2 array. E-ICP concept is applied to the 2${\times}$2 array ICP and its effect is examined. Characteristics of the plasma are measured, and photoresist etching is performed with oxygen plasma. Good etching characteristic in terms of etching rate and uniformity can be obtained with E-ICP.

• 암석학회지
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• 제17권1호
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• pp.44-50
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• 2008

대전지역에 날아온 황사의 근원지를 규명하기 위해 희토류원소 지구화학적 연구방법을 적용하였다. 대전지역 황사의 채집은 2007년 3월 31일에서 4월 2일 그리고 5월 25일에서 5월 27일 사이와 같이 총 2회에 걸쳐 수집되었다. 그리고 비교를 위해 한국지질자원연구원 주변의 토양을 채취하였다. 연구결과, 대전 지역 황사먼지의 경희토류(La-Gd) 분포도는 편평한 양상을 갖고 있고 Gd을 기점으로 중희토류(Gd-Lu)는 결핍되어 있으며 Eu의 이상은 관찰되지 않는다. 토양시료의 경우 경희토류의 경우 약간 부화된 경향을 보여주고, 중희토류의 분포도가 현저하게 결핍되어 있으며, Eu의 약한 부(-)의 이상을 보여준다. 이와 같이 대전지역 토양시료와 다른 양상을 갖는 대전 지역 황사먼지의 희토류원소 분포도의 특성은 중국의 오도스 사막 남동부의 풍성퇴적물과 매우 유사하다. 초기연구결과를 토대로 볼 때, 대전지역 황사의 주 근원지는 중국의 오도스 사막 남동부일 가능성이 매우 높은 것으로 나타났다.

• 한국광학회지
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• 제20권6호
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• pp.334-338
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• 2009

최근 디스플레이 기기의 수요가 증대되면서 대면적 노광에 대한 요구가 증대되고 있는데, 내부전반사(total internal reflection: TIR)홀로그래픽 리소그라피는 대면적 노광을 위한 효과적인 방법으로 연구가 진행되고 있다. TIR 홀로그래피에서는 일반적으로 레이저를 이용하여 영상을 기록하고 재생한다. 그러나 자외선 램프와 같은 비가간섭광을 이용하여 재생한다면, 가간섭성에 의해 나타나는 영상잡음을 줄일 수 있고, 대면적 노광에도 보다 용이할 것이다. TIR 홀로그램의 재생을 위하여 자외선 램프를 이용할 때, 램프의 유한한 선폭과 확산각이 재생 영상에 미치는 영향을 분석하고, 재생패턴에 나타나는 선폭 확대 결과를 실험을 통하여 검증하였다. ${\mu}m$ 규모의 선폭을 갖는 대면적 패턴을 TIR 홀로그램으로부터 얻기 위한 재생 광원으로, 가간섭성 광원인 레이저 대신 저잡음성과 경제성을 갖춘 일반적인 자외선 램프의 사용이 가능할 것으로 기대된다.

• 한국환경보건학회지
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• 제26권2호
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• pp.34-40
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• 2000

The purpose of this study was to investigate the seasonal variation of PAHs and to estimate their source characteristics in Taegu area. To do this, four sampling sites were selected to represent an industrial, a traffic, a traffic & residential, and a residential area in Taegu. Total of 72 samples had been collected from January, 1999 to September, 1999 on glass micro fiber filters by high volume air sampler. The PAHs in the total suspended particulate were extracted by a soxhlet process with dichloromethane and analyzed by GC/MSD, GC/FID. A statistical analysis was performed for the PAHs data set using a principal component analysis to derive important factor inherent in the interactions among the variables. The specific conclusions of this research are: 1) There was a significant seasonal and local variation in the atmospheric concentration of PAHs. The seasonal variation is winter>spring>Fall>summer, and the local variation is industrial>traffic>graffic & residential>residential area. 2) To evaluate the correlation between a measured PAHs and other affecting factors such as air pollutant concentration and meterological data, statistical analysis was performed. PAHs and other affecting factors such as air pollutant concentration and meterological data, statistical analysis was performed. PAHs have negative correlation with temperature (r=-0.593, p<0.05), radiation(r=-0.535, p<0.05), and O3(r=-0.719, p<0.05), but have positive correlation with NO(r=0.615, p<0.05) 3)Finally, multivariate analysis was performed for the PAHs dat set to identify and to estimate the source contributions of PAHs. According to results of statistical analysis, it could be identifies as three factors such as vehicular/gasoline, vehicular/diesel, and combustion in Taegu area.