• Nuclear Engineering and Technology
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• 제50권5호
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• pp.806-813
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• 2018

$^{222}Rn$ exists in nature in the form of a rare radioactive gas. In terms of environmental radiation, issues regarding $^{222}Rn$ have persisted because of its radiological hazardousness. Ulju County is one of the regions of Ulsan metropolitan city, with a population of 227,699. Ulju County has the highest density of industrial complexes in Korea. In this study, $^{222}Rn$ radioactivity concentration was measured and analyzed in 57 schools in Ulju County using 114 passive LR-115 type detectors to secure radiological safety and confirm basic information for reduction of resident exposure to $^{222}Rn$. The effective dose of $^{222}Rn$ was assessed to find the actual risk of the concentration surveyed in schools to human beings. The dose depended on four factors: subjects, $^{222}Rn$ concentration, dose coefficient, and time. The individuals subjected to dose estimation were classified into three types: students, teachers, and office workers. The subjects had different dwelling locations and times. The findings demonstrate that the radiological hazard to students and workers at schools in Ulju County owing to $^{222}Rn$ is negligible in terms of $^{222}Rn$ activity recommendation level.

• 한국지하수토양환경학회지:지하수토양환경
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• 제13권6호
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• pp.62-71
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• 2008

환경에는 매우 다양한 유해화학물질이 존재하며 지속적으로 새로운 화학물질이 개발되고 다시 환경 중으로 유출되고 있다. 화학물질의 관리나 규제를 위해서는 우선관리대상 오염물질(Priority Contaminants)을 결정해야 하는데, 이를 위한 과학적이고 정량적인 방법론으로는 우선순위선정(Chemical Ranking and Scoring; CRS)기법이 대표적이다. CRS기법에는 개발목적에 따라 다양한 평가인자들이 적용되는데 본 연구에서는 토양매체에서의 우선순위물질 선정시 필요한 인자를 제시하기 위해 다양한 CRS기법을 비교분석하여 토양특성을 고려할 수 있는 평가인자를 제시하였다. 연구대상 CRS는 국외에서 개발된 CHEMS-1, EURAM, SCRAM, ARET와 국내에서 개발된 CRS-Korea 및 그 외 기타 관련연구들이다. 기존에 개발된 CRS에 적용된 평가인자들을 비교분석한 결과 노출과 독성을 고려하여 우선순위물질을 선정하는데, 주로 화학물질의 잔류성, 생물축적성, 배출량 등을 공통적인 노출인자로 적용하고 있었고 독성인자로는 인체와 환경독성을 고려하고 있다. 본 연구에서는 토양매체의 우선순위물질선정을 위하여 이러한 CRS기법들이 공통적으로 적용하고 있는 인자들 이외에 토양매체의 특성을 고려할 수 있는 토양배출량, 토양오염 사고사건사례, 선진국의 규제국가수 등을 평가인자로 제안하였으며, 지하수매체와의 연계성을 위하여 지하수이동성 인자를 새로이 추가하였다. 본 연구결과는 CRS기법을 비교분석하여 토양에서의 유해화학물질 우선순위 선정시 고려되어야할 평가인자를 제안한 연구로 토양에 대한 CRS기법개발을 위한 기반연구로 활용될 수 있을 것이다.

• Journal of Preventive Medicine and Public Health
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• 제36권2호
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• pp.137-146
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• 2003

과거 군 복무 기간 동안 청력에 영향을 미치는 사격 및 포격 등 소음에 노출된 군 경력이 현재 소음 노출 근로자에게 어떤 청각학적 영향을 미치며, 소음성 난청의 발생과 관련이 있는지를 평가하고자 하였다. 중소규모 선박수리 및 건조업체 15개 사업체 440명을 대상으로 근로자의 일반 사항, 임상증상, 현재의 청력과 관련한 과거 이과적 병력, 군 복무시 충격소음의 상시적 노출 등의 군 경력, 이명 등의 자각증상에 관한 설문조사와 순음청력검사 및 중이검사를 시행하였다. 현 직종에서의 소음 노출군 중 과거 군에서 소음 노출군이 각 주파수별 청력역치와 평균 청력역치가 가장 컸으며, 특히 2-8kHz의 주파수 역치에서 차이가 크게 나타났다. 청력손실자의 비율 및 중증도의 정도가 현 직종에서의 소음 노출군 중 과거 군에서 소음 노출군이 가장 높은 비율을 보였으며, 특히 감각신경성 난청으로서 소음성 난청자가 통계적으로 유의하게 더 많았다. 이명은 현재 소음 노출 직종에 있는 군에서 높았으며, 그중 군 소음 노출군이 46.2%로 유의하게 더 높았다. 소음성 난청 여부를 종속변수로 한 로지스틱 회귀분석 결과, 연령, 현 직종 근무기간, 군 소음 노출력, 현 직종에서의 소음 노출 여부가 유의한 독립변수로 작용하였다. 우측 귀의 경우, 소음성 난청에 대한 군 소음 노출력의 비차비는 4.5이었고, 현 직종의 소음 노출의 비차비는 7.9이었다. 군 소음 노출 및 현 작업 소음 노출 여부에 따른 각 군별 좌우측 귀의 4 kHz 청력역치와 평균 청력역치는 I군에서 좌우측 귀 모두 나이 및 근무기간이 증가할수록 가장 크게 영향을 미치며 유의하게 증가하였으며 II군, III군, IV군 순으로 청력 역치가 증가하였다. 군에서 노출되는 충격소음은 청력손실과 이명 등 청각학적 영향을 미치며 사업장에서 소음 노출에 따른 소음성 난청의 발생에도 부가적인 영향을 미친다. 따라서 군에서의 소음 노출에 따른 청각학적 영향을 예방하기 위해서뿐만 아니라 소음 노출 근로자에 대한 청력 관리 측면에서도 이의 조기 진단, 치료, 보상 및 재활을 위해서는 군에서의 소음 노출 문제까지 함께 다루어야 함을 시사한다.

• 상하수도학회지
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• 제29권3호
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• pp.381-393
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• 2015

This study is carried out in order to propose a drought risk assessment methodology. This methodology is required to deal with practical questions that a variety of stakeholder often raise in the course of discussions on mitigation measures. With a focus on the socioeconomic aspect of drought, more particularly, residents' hardship from water scarcity, it suggests basic concepts and a system of methods in order to assess hazard, exposure, vulnerability and risk. The case study shows a considerable possibility of the methodology in evaluating potential levels of damages in a certain area, in identifying the boundary of districts where risk is disproportionately concentrated, and also in understanding the underlying risk factors of those districts. The authors think that the proposed methodology is able to offer risk information in terms of socioeconomic damages, and therefore contribute to reducing information gaps that policy-makers are currently encountered with.

• 대한안전경영과학회지
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• 제16권3호
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• pp.219-229
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• 2014

Employees used computer significantly(IT employee) is increased by technological development in workplace. This study tried to find the magnitude of IT employees and the profile of their working conditions and ill health experiences in South Korea. Korean Working Conditions Survey was used with descriptive and mean difference test in order to find the difference working conditions and ill health status among the groups classified by the degree of using computer during work. Some of working conditions was positively correlated with the density of computer use such as work autonomy, the exposure of repetitive movement of hand and arms. The pain of upper extreme was also more frequently found in the highest user group of computer than lower user groups. Based on the result of hierarchical regression analysis, the effect of computer using on the experience of work-related symptoms after controlling other factors was shown as U shape. This study as heuristic one suggest that some of depth analysis with hypothesis will be done to identify the causes and pathway of impact of computer use.

• 한국직업건강간호학회지
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• 제23권3호
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• pp.180-188
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• 2014

Purpose: The purpose of this study was to compare the health status between foreign workers and native workers and to examine the influencing factors of health status of foreign and native workers. Methods: This was a secondary analysis of the data collected from the 3rd (2011) Korean Working Conditions Survey (KWCS). The sample included 101 foreign workers and 101 native workers matched by age and gender. Results: The difference in health status between foreign workers and native workers was not statistically significant. The most commonly complained health problem of foreign workers was muscle pain of the upper limbs. Among foreign workers, hazard exposure, coworker support and supervisor support were significant predictors of health status. Among native workers, income level and obesity were significant predictors of health status. Conclusion: For health management and health promotion of foreign workers, employers and health providers need to establish coworker supporting systems in workplace and improvement strategies of work environment. Particularly, they must pay closer attention to management of foreign workers' musculoskeletal disorder.

• Safety and Health at Work
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• 제6권4호
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• pp.279-288
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• 2015

Background: In this study, the measurement of job stress of electric overhead traveling crane operators and quantification of the effects of operator and workplace characteristics on job stress were assessed. Methods: Job stress was measured on five subscales: employee empowerment, role overload, role ambiguity, rule violation, and job hazard. The characteristics of the operators that were studied were age, experience, body weight, and body height. The workplace characteristics considered were hours of exposure, cabin type, cabin feature, and crane height. The proposed methodology included administration of a questionnaire survey to 76 electric overhead traveling crane operators followed by analysis using analysis of variance and a classification and regression tree. Results: The key findings were: (1) the five subscales can be used to measure job stress; (2) employee empowerment was the most significant factor followed by the role overload; (3) workplace characteristics contributed more towards job stress than operator's characteristics; and (4) of the workplace characteristics, crane height was the major contributor. Conclusion: The issues related to crane height and cabin feature can be fixed by providing engineering or foolproof solutions than relying on interventions related to the demographic factors.

• 대한인간공학회지
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• 제27권1호
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• pp.45-51
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• 2008

The purpose of this survey was to identify ergonomic risk factors of work-related musculoskeletal disorders (MSD) and understand the current MSD risk status in the wholesale/retail industry. The field survey was conducted at 120 wholesale/retail establishments, and the cause of MSD occurred from the national industrial accident statistics by the Ministry of Labor in 2006 was analyzed in terms of company size, a term of work, job title, and cause of occurrence. The numbers of disasters on MSD were 602 which were included 432 disasters who met with low back pain by incident. A checklist was developed by KOSHA to use for the field survey. A total of 419 tasks were identified at the 120 establishments surveyed. The highest frequency was Task 2(45%) which was mostly observed in repetitive work (e.g. displaying, scanning, cutting or wrapping of goods). The second and third were Task 9(34%) and Task 8(14%) which were identified in manual materials handling (e.g. lifting, lowering, carrying or stocking of goods). The results suggest that the three Tasks should be first considered for the control in wholesale/retail industry and that exposure to MSD risk factors in those Tasks should be primarily addressed in order to reduce MSD risk in that industry.

• 분석과학
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• 제25권1호
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• pp.69-75
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• 2012

본 연구에서는 학교 주변 문방구에서 쉽게 구입할 수 있는문규류 4개 제품군(연필, 지우개, 노트, 색종이) 22종의 학용품을 조사대상 시료로 선정하여 환경보건법의 환경유해인자로서 관리되고 있는 프탈레이트 8종의 함유특성을 파악하였다. 본 연구결과 조사대상 8종의 프탈레이트류 중 Benzyl butyl phthalate (BBP), Di-n-octyl phthalate (DNOP) 및 Diisodecyl phthalate (DIDP)는 모든 시료에서 검출한계 미만(불검출)으로 나타나 문구류에서는 사용하고 있지 않는 것으로 나타났다. A군의 경우에는 일부 시료에서 Di(2-ethylhexyl) phthalate (DEHP) 및 Diisononyl phthalate (DINP)가 22%~28% 검출되었으며, A-1, A-3 및 A-4의 시료에서는 DINP가 각각 28%, 24% 및 28% 검출되었으며, B군은 조사대상 시료 6건 모두 규제농도인 1,000 ppm 이하로 검출되었다. 또한, C-2 시료에서 Dibutyl phthalate (DBP)가 1% 검출되었으며, C-1 및 C-6 시료에서 DEHP가 0.3% 정도 검출되었으며, D-3 시료에서 Di(2-ethylhexyl) adipate (DEHA)가 0.1% 수준으로 검출되었다. 본 연구결과 조사대상 프탈레이트류 중 DINP는 주로 지우개에서만 가장 높은 농도로 검출되었으며, 지우개는 저학년일수록 많이 사용하는 학용품으로 피부 접촉을 통해 노출될 가능성이 큰 물질인 것으로 판단되었다.

• Molecular & Cellular Toxicology
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• 제1권2호
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• pp.73-77
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• 2005

Nickel is the one of potent environmental, the occupational pollutants and the classified human carcinogens. It is a serious hazard to human health, when the metal exposure. To prevent human diseases from the heavy metals, it is seemingly important that understanding of how nickel exerts their toxicity and carcinogenic effect at a molecular and a genomic level. The process of nickel absorption has been demonstrated as phagocytosis, iron channel and diffusion. Uptaked nickel has been suggested to induce carcinogenesis via two pathways, a direct DNA damaging pathway and an indirect DNA damaging pathway. The former was originated from the ability of metal to generate Reactive Oxygen Species (ROS) and the reactive intermediates to interact with DNA directly. Ni-generated ROS or Nickel itself, interacts with DNAs and histones to cause DNA damage and chromosomal abnormality. The latter was originated from an indirect DNA damage via inhibition of DNA repair, or condensation and methylation of DNA. Cells have ability to protect from the genotoxic stresses by changing gene expression. Microarray analysis of the cells treated with nickel or nickel compounds, show the specific altered gene expression profile. For example, HIF-I (Hypoxia-Inducible Factor I) and p53 were well known as transcription factors, which are upregulated in response to stress and activated by both soluble and insoluble nickel compounds. The induction of these important transcription factors exert potent selective pressure and leading to cell transformation. Genes of metallothionein and family of heat shock proteins which have been known to play role in protection and damage control, were also induced by nickel treatment. These gene expressions may give us a clue to understand of the carcinogenesis mechanism of nickel. Further discussions on molecular and genomic, are need in order to understand the specific mechanism of nickel toxicity and carcinogenicity.