• 한국시뮬레이션학회논문지
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• 제17권2호
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• pp.63-74
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• 2008

공정 개선의 문제는 원가 절감, 수익구조 개선을 목표로 하는 생산 전략부서, 생산 계획에 의해 제시된 제품의 목적 생산량을 달성할 수 있는 공정 설계하고자 하는(설계 공정 능력, Tact time) 공정 설계 부서의 공통 요구사항이다. 목표하는 생산량을 달성하기 위해 작게는 라인밸런싱(Line-Balancing), 병목공정 제거를 수행하고 있으며, 크게는 설비 증설, 작업자 증원 등의 공정 개선을 시도한다. 문제는 대부분의 경우, 공정 개선 프로세스가 정적 예측 기반의 수리적인 방식에 기인하고 있다는 점이며, 특히 라인 생산 기반의 컨베이어 공정의 경우, 컨베이어의 이송 능력에 따른 대기시간 부분이 배제되고 있다는 것이다. 공정 대기시간은 설비의 정미시간과는 별개의 문제로 설비의 싸이클 타임(Cycle Time)의 수치에 따라 변동하는 변수로서 중요하다. 이에 본 논문에서는 H 사의 컨베이어 라인 공정을 대상으로 이산 사건 기반의 시뮬레이션을 수행하여 일련의 공정 개선 프로세스를 밟아가며, 컨베이어에 의해 발생하는 공정 대기시간의 공정 개선에의 기여도를 측정하여 공정 개선의 주요 변수로서 제시하고자 한다.

• 사회복지연구
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• 제48권4호
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• pp.221-249
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• 2017

본 연구는 산재근로자들의 직업복귀 형태에 따른 고용유지 기간에 미치는 영향을 실증적으로 규명함으로써 원직복귀 시에는 고용을 유지할 수 있는 방안, 원직복귀에 실패한 경우에는 어떠한 대상을 우선적으로 개입해야 하는지에 대한 방안을 제시하는 데에 목적이 있다. 이를 위해 선행연구 고찰을 바탕으로 한 영향요인을 구성하고, 이를 산재보험패널조사 내에 1,292명을 분석함으로써 각 요인을 파악하였다. 분석결과, 원직복귀집단의 경우 평균 46.6개월, 타직복귀집단의 경우 평균 34.2개월 동안 고용을 유지하고 있는 것으로 나타났다. 또한, 타직복귀가 원직복귀에 비해 여러 번 실업을 경험하는 것으로 나타났으며, 기타 일반적 특성에서도 열악한 노동시장 환경임을 확인하였다. 실증분석 결과, 두 집단 모두 직업복귀기간이 길수록 지속적인 고용을 유지하고 있는 것으로 나타났다. 또한, 타직복귀 시 연령이 낮을수록, 요양기간이 짧을수록, 전반적인 건강상태가 좋지 않은 경우일수록, 사회심리재활서비스, 교육 훈련 및 직업훈련을 경험한 경우 고용유지확률이 높게 나타났다. 이를 토대로 직업복귀기간의 적절한 유예기간 설정과 재해 당시 근로환경이 열악한 근로자의 원직복귀 혹은 산재보상 및 재활서비스 우선적 개입, 산재근로자의 직장복귀 성공 이후에도 사례관리 등을 통한 산재재활서비스의 적극적인 홍보 등을 정책 대안으로 제시하였다.

• 한국산업보건학회지
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• 제29권2호
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• pp.141-158
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• 2019

Objectives: An adverse outcome pathway is a biological pathway that disturbs homeostasis and causes toxicity. It is a conceptual framework for organizing existing biological knowledge and consists of the molecular initiating event, key event, and adverse output. The AOP concept provides intuitive risk identification that can be helpful in evaluating the carcinogenicity of chemicals and in the prevention of cancer through the assessment of chemical carcinogenicity predictions. Methods: We reviewed various papers and books related to the application of AOPs for the prevention of occupational cancer. We mainly used the internet to search for the necessary research data and information, such as via Google scholar(http://scholar.google.com), ScienceDirect(www.sciencedirect.com), Scopus(www.scopus. com), NDSL(http: //www.ndsl.kr/index.do) and PubMed(http://www.ncbi.nlm.nih.gov/pubmed). The key terms searched were "adverse outcome pathway," "toxicology," "risk assessment," "human exposure," "worker," "nanoparticle," "applications," and "occupational safety and health," among others. Results: Since it focused on the current state of AOP for the prediction of toxicity from chemical exposure at work and prospects for industrial health in the context of the AOP concept, respiratory and nanomaterial hazard assessments. AOP provides an intuitive understanding of the toxicity of chemicals as a conceptual means, and it works toward accurately predicting chemical toxicity. The AOP technique has emerged as a future-oriented alternative to the existing paradigm of chemical hazard and risk assessment. AOP can be applied to the assessment of chemical carcinogenicity along with efforts to understand the effects of chronic toxic chemicals in workplaces. Based on these predictive tools, it could be possible to bring about a breakthrough in the prevention of occupational and environmental cancer. Conclusions: The AOP tool has emerged as a future-oriented alternative to the existing paradigm of chemical hazard and risk assessment and has been widely used in the field of chemical risk assessment and the evaluation of carcinogenicity at work. It will be a useful tool for prediction, and it is possible that it can help bring about a breakthrough in the prevention of occupational and environmental cancer.

• 대한불안의학회지
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• 제15권1호
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• pp.45-52
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• 2019

Objective : The objective of this study is to determine the effects of fear of Middle East respiratory syndrome (MERS) on socio-psychological health during an outbreak of MERS and the post-traumatic stress as a mediator on the relationship between stress and socio-psychological health. Methods : Visual Analog Scale, Impact of Event Scale -Revised, Psychosocial well-being index short form was implemented for 150 medical persons who worked at the hospital in which exposure to MERS cases had been confirmed and 96 ordinary people. A Pearson correlation coefficient and a hierarchical multiple regression was carried out to confirm the effect of fear of MERS and the mediating effect of post-traumatic stress between fear and socio-psychological health. Results : The higher the fear, the lower the socio-psychological health in both healthcare workers and the public (r=0.32, p<0.01) and the higher post-traumatic stress (r=0.32, p<0.01). But, the research results showed that only healthcare workers had a partially mediating effect of post-traumatic stress in the relationship between fear and socio-psychological health (${\beta}=0.45$, t=6.33 p<0.001), (${\beta}$ value : 0.39>0.26). Conclusion : This study demonstrated that the post-traumatic stress can indirectly lead to a negative effect on the socio-psychological health of healthcare workers when under the fear of MERS and shows adverse effects on psycho-social wellbeing. This suggests that clinical intervention and psycho-social approach aiming at reducing post-traumatic stress is important to maintain mental health during crisis development.

• 한국산업보건학회지
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• 제24권4호
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• pp.556-565
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• 2014

Objectives: This study is aimed at inquiring into the grasp of real condition of working environment and improvements by calculating the hypertension distribution consequent on job stress risk and exposure level of alleviating factors. In addition, this study is intending to estimate the hypertension distribution through socio-demographic factors and level of stressors occurring at working environment, such as high workload, low control, low support, job insecurity, long working hours, low income. Methods: This study estimated the hypertension distribution using the tertiary Korean Working Conditions Survey data, and conducted comparative analysis according to the category of individual questionnaire items using odds ratio. Result: As a result of study, it was found that in the event that working environment satisfaction is low and business & an immediate superior's attitudes are negative, the hypertension distribution was high. Particularly, it was found that physical risk factor musculoskeletal risk factor, and mental risk factor in a workplace were all increasing the hypertension distribution. Conclusions: With the aged workers' labor market participation ratio increasing, hypertension could be a major issue in the field of Occupational Safety and Health. Thus, it's necessary that the relevant employer should lower the hypertension distribution through creation of pleasant working environment and inducement of workers to improve in the relations with their superiors. As for the uppermost limit of this study, there is a limit to clarifying the mechanism of hypertension through multivariate statistics analysis because it's difficult to establish causal relationship by individual questionnaire item as the working conditions survey is made by cross-sectional study. In the follow-up research, this study is going to do research on the mechanism of hypertension through questionnaire supplementation and in-depth analysis.

• 한국산학기술학회논문지
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• 제9권5호
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• pp.1265-1270
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• 2008

자동차 제조에 들어가는 부품들은 자동차의 종류에 따라 규격과 내용이 다르고, 자동차 생산 버전에 따라 같은 부품이라도 그 특성과 요구사항이 모두 다르다. 또한 생산라인에 있어서도 각 서별로 업무가 분담되어 있어서 하나의 부품에 대한 변경 사항이 나타나면 각 팀 또는 서별로 변경된 정보를 인지해야 하지만, 현재 각 부서별로 이와 같은 이벤트가 발생하면 수작업을 통한 부품관리를 해야 하기 때문에 정보의 단일화가 어려운 실정이다. 따라서 본 연구에서는 POP 시스템을 자동차 부품업체에 적용하여 POP 기반의 자동차 부품 생산통합관리 시스템을 구축하였다. 이 시스템은 기계 설비 작업자 생산품에서 발생하늘 정보들을 실시간으로 지원하고, 자동적으로 데이터 갱신이 이루어질 수 있도록 하였다. 이 시스템이 도입되면 작업공정 시간과 비용 면에서 현저히 절감될 것으로 예상된다.

• 대한불안의학회지
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• 제6권1호
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• pp.65-70
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• 2010

Objectives : Indirect contact with trauma may occur when a person empathically listens to detailed descriptions, exposing the person to intense emotional pain from trauma victims. Although less severe than direct trauma, indirectly traumatized persons may experience the same fear, rage, and despair as direct trauma victims. This phenomenon has been variously termed vicarious trauma, traumatic countertransference, burnout, compassion fatigue, and secondary traumatic stress. Using a psychiatric symptoms questionnaires, this study investigated the effects of indirect exposure to co-worker's trauma on the mental health of firefighters who had not directly experienced traumatic events in the previous year. Methods : We administered self-report questionnaires, such as the Impact of Event Scale-Revised (IESR) and Alcohol Use Disorder Identification Test (AUDIT), to firefighters working at two fire stations in a metropolitan city. We analyzed 188 of 232 collected surveys, after excluding falsely entered data (28 cases) and questionnaires by directly-traumatized victims (16 cases). Results : Alcohol consumption and posttraumatic stress disorder (PTSD) symptoms, as determined by the AUDIT and IES-R, were significantly higher in the indirectly-traumatized group. The ratio of high-risk members scoring higher than 23 in IES-R was larger in the indirectly traumatized group, although this was not statistically significant. Conclusion : Alcohol consumption was significantly higher in the indirectly traumatized group. This group also included more members at high risk for PTSD. Further research, with a larger group of indirectly traumatized firefighters and ongoing investigation of PTSD development and other psychiatric symptoms, is needed.

• 신경정신의학
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• 제56권1호
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• pp.28-34
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• 2017

Objectives The purpose of this study was to evaluate psychological effects of an outbreak of Middle East respiratory syndrome (MERS), a newly emerged infectious disease, on doctors. Methods After the MERS outbreak was over, we conducted an online survey of doctors who worked at the hospitals in which exposure to MERS cases had been confirmed or who were directly involved in MERS diagnosis and treatment. The Patient Health Questionnaires-9 (PHQ-9) and the Impact of Event Scale-Revised (IES-R) assessment methods were used to assess the severity of depressive and posttraumatic stress symptoms among the 64 doctors participating in the survey. Results The results of the survey indicate that 26.6% (n=17) of participants exhibited depressive symptoms and 7.8% (n=5) had post-traumatic stress symptoms. The doctors employed at hospitals with MERS cases had higher PHQ-9 and IES-R mean scores than those in doctors were not so employed. In contrast, there was no significant difference in those test scores between doctors who participated directly in MERS diagnosis and treatment and those doctors who did not. Conclusion The survey demonstrated that 28.1% (n=18) of doctors involved in MERS care suffered from depressive or posttraumatic stress symptoms, even though the MERS infection was being controlled. Working at a hospital with MERS cases was the primary determinant of the adverse psychological outcomes among doctors ; however, direct participation in the diagnosis and care of MERS patients was not significantly related to such outcomes.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3824-3836
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• 2021

Workers' safety from radiological exposure in a 1 ton/day capacity spent resin treatment facility was evaluated according to the operating times and outflow rate due to process related leakages. The conservative annual dose based on the operating times of the workers exceeded the dose limit by at least 7.38E+01 mSv for close work. The realistic dose range was derived as 1.62E+01 mSv-6.60E+01 mSv. The conservative and realistic annual doses for remote workers were 1.33E+01 mSv and 3.00E+00 mSv respectively, which were less than the dose limit. The MWR was identified as the major contributor to worker exposure within the 1 h period required for removal of radioactive materials. The dose considering both internal and external exposures without APF was derived to be 1.92E+01 mSv for conservative evaluation and 4.00E+00 mSv for realistic evaluation. Furthermore, the dose with APF was derived as 7.27E-01 mSv for conservative evaluation and 1.51E-01 mSv for realistic evaluation. Considering the APF for leakage from all parts, the dose range was derived as 1.25E+00 mSv-2.03E+00 mSv for conservative evaluation and 2.61E-01 mSv-4.23E-01 mSv for realistic evaluation. Hence, it was confirmed that radiological safety was secured in the event of a leakage accident.

• 전기전자학회논문지
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• 제27권3호
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• pp.225-233
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• 2023

본 논문은 해양사고 시 인체 인양정보를 모니터링하는 시스템을 구현한다. 모니터링 시스템은 수중환경 정보를 송신하는 인양기구제어기를 통하여 초음파 통신을 수행하며, 수상에서는 관제센터 또는 모선까지 10 km내 GPS 정보를 제공하기 위해 LoRa 통신을 수행한다. 수중 인양제어기는 공압 센서, 자이로 센서 및 온도센서 정보를 전송한다. 수중조건은 수심 10m 마다 수압 1기압씩 높아지고, 기구의 공기양은 육상에 비해서 1/2씩 줄어드는 환경에서 60 kg 수중 마네킹을 모델을 사용한다. 인양기구 SMB(Surface Marker Buoy)에 38g의 CO2 카트리지 1개를 사용하여 10 sec 이내에 수면 상승 조건을 기반으로 인양기구 출수 시험을 한다. 수중 통신은 수심 40m에서 100m까지 2,400bps 초음파 센서를 이용하여 데이터 전송환경을 구성한다. 모니터링 신호는 수심, 수온, 방향각 등을 수면 위의 구조요원에게 제공함으로써 인양작업자의 안전과 안전한 인체 구조를 목표로 한다.