• 방사선산업학회지
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• 제11권3호
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• pp.123-130
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• 2017

Concerns about high radiation exposure to the hands of radiation workers who may contact with radioactive contamination on surfaces in a nuclear power plant (NPP) had been raised, and the Korean regulatory body required the extremity dose estimation during contact tasks with radioactive materials. Korean NPPs conducted field tests to identify the incident radiation to the hands of radiation workers who may contact with radioactive contamination during maintenance periods. The results showed that the radiation fields for contact tasks are dominated by high energy photons. It was also found that the radiation doses to the hands of radiation workers in Korean NPPs were much less than the annual dose limits for extremities. This approach can be applicable to measure and estimate the extremity dose to the hands of medical workers who handle the radioactive materials in a hospital.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권6호
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• pp.82-94
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• 2021

Facilities for low impact development (LID) or groundwater recharge have the high potential spreading groundwater nitrate contamination because of the rapid infiltration. This study was initiated to remove nitrate from the waters using agricultural byproducts as organic sources for denitrification during infiltration. As the first step of this purpose, we experimentally tested the denitrifying efficiency of 4 organic materials (pine tree woodchips, cherry leaves, rice straws, and rice hulls) and tried to identify the key factors controlling the efficiency. For this study, we precisely investigated the change of chemical reactions during the experiment by analyzing various geochemical parameters. The result shows that the denitrification efficiency is not simply linked to the availability of the easily decomposable contents in the organic matter. It is found that avoiding the severe pH decrease due to the CO₂ generation is the essence to derive the efficient denitrifying conditions when organic matters were used.

• 문화기술의 융합
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• 제9권2호
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• pp.569-574
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• 2023

콘크리트 구조물의 적절한 유지관리를 위해서 다양한 결함에 대해 사전에 파악하고 유지관리하는 것이 필요하다. 현재 방법으로는 규모가 큰 사회기반시설물의 점검 시 효율성, 안전성, 신뢰성에 문제가 있어 새로운 점검 방식의 도입이 필요하다. 최근에는 영상에 대한 딥러닝 기술이 발달함에 따라 콘크리트 결함 분류 연구가 활발히 진행되고 있다. 하지만, 균열 외에 오염과 박락 등에 대한 연구는 제한적이다. 본 연구에서는 사전에 학습된 딥러닝 모델에 대한 전이학습을 통한 다양한 콘크리트 결함 유형 분류 모델을 개발하고, 정확도를 저하시키는 요인을 도출 및 향후 발전 방향을 제시하였다. 이는 향후 콘크리트 유지관리 분야에서 활용도가 높을 것으로 예상된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제22권1호
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• pp.1-12
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• 2017

Nitrate ($NO_3^-$), a common surface water and groundwater pollutant, poses a serious environmental problem in regions with intensive agricultural activities and dense population. It is thus important to identify the source of nitrate contamination to better manage water quality. Due to the distinct isotope compositions of nitrate among different origins, the dual isotope analysis (${\delta}^{15}N$ and ${\delta}^{18}O$) of nitrate has been widely applied to track contamination sources. This paper provided the underlying backgrounds in the isotope analysis of nitrate, which included typical ranges of ${\delta}^{15}N$ and ${\delta}^{18}O$ from various nitrate sources, isotope fractionation, the analytical methods used to concentrate nitrate from samples, and the potential limitations of the dual isotope analysis along with the resolutions. To enhance the applicability of the dual isotope analysis as well as increase the ability to interpret field data, this paper also introduced several case studies. Furthermore, other environmental tracers including ${\delta}^{11}B$ and $Cl^-/Br^-$ ratios were discussed to accompany the dual isotope analysis for better assignment of contamination sources even when microbial transformation of nitrate and/or mixing between contaminant plumes occur.

• 대한지하수환경학회지
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• 제5권3호
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• pp.141-147
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• 1998

본 연구는 괴산군 덕평리 지역의 지하수 수질과, 본 지역에 분포하는 혹색 셰일층과 탄층에 기인한 토양과 암석의 중금속 부화현상이 이 지역 지하수의 수질오염에 미치는 영향을 규명하고자 수행되었다. 본 지역의 지하수질은 지하수환경에서 일어나는 지질매체의 반응이 주로 규산염광물의 풍화인 경우와 탄산염광물의 풍화인 경우로 크게 구분된다. 규산염광물의 풍화가 주된 반응인 시료들은 음이온의 주성분이 SO$_4$$^{2－}$ 인 시료들과 Cl$^{-}$ 인 시료들로 세분가능하며, 이러한 수질특성은 지하수와 접하는 암석의 풍화특성에 관계되는 것으로 사료된다. 암석과 토양내 부화된 중금속에 의한 천부 지하수의 오염현상은 국내외의 먹는 물 수질기준에 비교하였을 때 발견되지 않았으나, 국지적으로는 산성폐수의 생성과 지하수환경으로의 유입이 발견되었다. 또한 질산성-질소에 의하여 수질기준의 2~3배에 달하는 오염이 밝혀졌으며, 오염원은 생활하수 내지 비료성분의 지하수내 유입으로 사료된다.

• 대한방사선기술학회지:방사선기술과학
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• 제38권4호
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• pp.395-401
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• 2015

영상의학과의 흉부엑스선 검사에서 감염관리에 대한 기기의 오염 정도를 세균학적으로 확인하고 균을 동정하여 병원감염의 예방과 감염관리방안을 마련하는데 목적이 있다. 영상의학과 흉부 엑스선 검사에서 환자의 기기 접촉부위인 어깨, 손, 턱, 흉부 측면촬영의 손잡이 부위를 70% 이소프로필 알코올로 소독하기 전과 후를 면봉으로 검체를 채취하여 세균을 동정하여 비교하여 분석하였다. 흉부 엑스선 기기에서 소독전의 측면촬영의 손잡이에서 그람 양성의 Staphylococcus가 분리되었다. 최종동정을 위해 노보바이오신 (nobobiocin) 항생제 시험을 실시하여 민감성으로 Staphylococcus epidermidis로 확정하였다. 흉부촬영 기기에서 측면촬영의 손잡이 부위를 소독 전에 Staphylococcus epidermidis 균이 검출되었다. 흉부엑스선 검사에서 기기를 주기적인 소독 및 멸균을 실시하여 병원감염을 예방하는 관리방안을 마련하여야 한다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2000년도 International Meeting 2000
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• pp.94-101
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• 2000

We investigated the viral contamination of water environment including tap water in Korea. River water used for source water was analyzed about monthly between 1997 and 1999 over a period 26 months. A total of 22 tap water samples were collected in 10 sites in 2 urban areas between 1997 and 1998 over a 11 months. All samples were examined for infectious enteroviruses and adenoviruses by a cell culture technique followed by PCR amplification. To identify the recovered viruses from tap water, sequence analysis of PCR products was performed. Infectious viral particles were detected in river water all year round, ranging from 0.93 to 17.3 Most Probable Number of Infectious Unit (MPNIU) /100L. Tap water samples also contained infectious viral particles. The frequency of enteroviruses and adenoviruses in tap water were $50.0\%$ (11/22) and $36.7\%$ (8/22), respectively. Both enteroviruses and adenoviruses were detected in five tap water samples $(22.7\%)$. The level of viral contamination in tap water was quite high, ranging from 0.2 to 2.9 MPNIU/100L, far above the recommended virus level in drinking water set by the U.S. EPA. Poliovirus type 1 derived from vaccine was frequently detected and the remainder comprised coxsackievirus B type or echovirus type 6, which were causative agents of aseptic meningitis in Korea in 1997 and 1998, respectively. Several types of adenovirus were detected in tap water samples and some water samples were found to contain adenoviruses which were closely related to enteric adenovirus type 40 and 41. This stusy shows that surface water and tap water in Korea may be exposed to the risk of viral contamination, especially from recently recognized viruses and this constitutes a potential public health hazard.

• Perspectives in Nursing Science
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• 제10권1호
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• pp.65-76
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• 2013

Purpose: To identify an associations between health care workers' uniforms and health care-associated infection. Methods: Electronic databases, including Ovid-Medline, the Cochrane Library, CINAHL, EMBASE, KMbase, and KoreaMed, were searched. The search terms included doctor, nurse, health care worker/staff/assistant, clothing, (white) gown, uniform, (neck)tie, and attire. Only papers published in English and Korean were included. Results: 16 studies were selected from 1,900 references screened. All of the studies were non-comparative studies except for one. Four were conducted with doctors, six with nurses, one with health care workers including physiotherapists and one for medical staff plus visitors in a neonatal intensive care unit. Doctors more frequently changed their uniforms than neckties; therefore, the degree of contamination was more serious in neckties. The cuff zone was more likely to be heavily contaminated than other areas of long-sleeve gowns. Coats become contaminated quickly once worn, and colony counts reached a similar level within the first few hours after wearing them. Wearing a plastic apron or protective clothing did not prevent the bacterial contamination of nurses' uniforms, and the best way to decrease the contamination was changing to newly laundered uniforms before starting every duty. Conclusion: Healthcare workers' uniforms are a potential source of health care-associated infection although there was no robust evidence. The government must establish standards for laundering of uniforms or a requirement for institutions to provide a laundering service for healthcare workers' uniforms.

• 지질공학
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• 제12권4호
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• pp.379-394
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• 2002

이 연구는 서울특별시 지하철 A설계구간에서, 현재 시점의 지하수 수질 및 오염을 파악함으로써, 추후 지하철 공사로 인한 수질 악화 발생시, 이에 과학적으로 대처하기 위해 수행되었다. A설계구간을 따라 총 21개 시추공에서 지하수 시료를 채취.분석하였으며, 그 결과 배경수질은 주로 $Ca-HCO_3$ 유형으로 나타났다. 전체시료 가운데, 국내 먹는물 수질기준을 초과하지 않은 시료는 1개이며, 나머지 20개 시료는 $SO_4$, Cd, Pb, Fe, Mn, Al, F, $NO_3-N$ 등이 먹는 물 수질 기준치를 초과하여 있었다. 오염의 형태는 일부 시료에서 몇몇 화학 원소의 농도가 나머지 시료에서의 농도보다 크게 나타나는 점오염의 형태를 띄었다. 화학분석 자료와 포화지수 분석을 통하여, 지하에 매립된 물질과 지표 퇴적물이 일차적인 오염원임을 추정하였다. 요인분석 결과, 연구지역 내 지하수 시료의 수리화학적 특성의 약 47%가 오염 인자에 의해 영향을 받고 있는 것으로 나타났다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권1호
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• pp.17-23
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• 2019

Clean soil environment is of crucial importance to sustain lives of ecosystem and humans. With rapid industrialization, there has been a great increase of soil contamination by accidental releases of petroleum products. In general, soil remediation is an expensive and time-consuming process as compared to cleanup of water and air. Moreover, determining the source and responsible parties of soil pollution often turns into legal conflicts and that further delay the cleanup process of contaminated sites. In practice, total petroleum hydrocarbon (TPH) analysis has been employed to determine the petroleum species and to track down the responsible polluters. However, this approach often suffers from differentiating similar TPH species. In this study, we analyzed TPH chromatogram patterns of 24 domestic petroleum products in specific carbon ranges (${\sim}C_{10}$, $C_{10}-C_{12}$, $C_{12}-C_{36}$, and $C_{36}{\sim}$) and the fractional changes of THP ratio in the mixture products of gasoline, kerosene and diesel. The proposed TPH analysis method in this study could serve as a useful tool to better analyze the petroleum species in soils contaminated with complex oil mixtures, and ultimately be used to identify the polluters of soil.