• Nuclear Engineering and Technology
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• 제56권3호
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• pp.1081-1090
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• 2024

The liquid Lead-bismuth eutectic is used as the coolant for Gen-IV reactor concepts. However, due to its strong corrosive and high operating temperature, it is difficult to accurately measure the flow rate in long-term operating conditions. Venturi flowmeter is a simple structured flowmeter, which plays a very important role in the flow measurement of high-temperature liquid metals, especially since the existing flowmeters are difficult to be competent. It has the advantages of easy maintenance and stable operation. Therefore, it is necessary to study the operating conditions of the venturi flowmeter under high-temperature conditions. This work performs a series of simulations of the fluid-solid interaction between the flow liquid metal and venturi flowmeter with COMSOL software, including the dimensional sensitivity analysis of the venturi flowmeter to explore the most suitable structure and parameters for liquid heavy metal, the sensitivity analysis of the geometric parameters of the venturi tube on the varying conditions. It shows that when the contraction angle of the venturi flowmeter is 33°, the diffusion angle is 13°, the diameter of the throat is 8 mm, and the temperature of the lead-bismuth eutectic is 733.15 K, it is most suitable for the measurement in the lead-bismuth circuit.

• Journal of Preventive Medicine and Public Health
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• 제41권5호
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• pp.345-354
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• 2008

Objectives : Our objective is to review and summarize the previous studies on the health effects of exposure to oil spills in order to make suggestions for mid- and long-term study plans regarding the health effects of the Hebei Spirit oil spill occured in Korea. Methods : We searched PubMed to systemically retrieve reports on the human health effects related to oil spill accidents. The papers' reference lists and reviews on the topic were searched as well. Results : We found 24 articles that examined seven oil spill accidents worldwide over the period from 1989 to August 2008, including the Exxon Valdes, Braer, Sea Empress, Erika, Nakhodka, Prestige and Tasman Spirit oil spills. Most of the studies applied cross-sectional and short-term follow-up study designs. The exposure level was measured by assessing the place of residence, using a questionnaire and environmental and personal monitoring. Studies on the acute or immediate health effects mainly focused on the subjective physical symptoms related to clean-up work or residential exposure. Late or mid-term follow-up studies were performed to investigate a range of health effects such as pulmonary function and endocrine, immunologic and genetic toxicity. The economic and social impact of the accidents resulted in the socio-psychological exposure and the psychosocial health effects. Conclusions : Studies of the health effects of exposure to oil spills should consider a range of health outcomes, including the physical and psychological effects, and the studies should be extended for a considerable period of time to study the long-term chronic health effects.

• 한국구조물진단유지관리공학회 논문집
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• 제25권6호
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• pp.185-192
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• 2021

본 연구에서는 거푸집 패널이 부착된 실물 스케일의 중공슬래브 Mock-up을 제작하여 즉시 처짐 및 장기 처짐에 대한 플랫 플레이트 중공 슬래브의 안전성을 평가하고자 한다. 중공재가 적용된 Mock-up 실험체의 중공률은 24%로 설계하였다. 콘크리트 블록 하중 재하 시 슬래브의 가장 중앙부의 처짐인 No2의 경우 재하 시 처짐이 8.88mm 발생하였으며 이는 즉시 처짐에 대한 기준 값(l_n/240=17.93mm)에 비하여 안전한 값을 나타내고 있다. 3개월간 처짐 량 계측 결과, 중앙부 처짐 량은 초기 처짐에서 6.792mm 더 추가되어 처짐이 발생하였지만, 이는 국내 구조 기준에서 제시하고 있는 사용하중에 의한 기준 값을 만족하고 있는 것으로 나타났다.

• 한국전자거래학회지
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• 제12권3호
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• pp.235-249
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• 2007

워크플로우 시스템은 긴 주기의 프로세스의 실행을 통제하는 소프트웨어 시스템이다. 조직의 구성원들이 프로세스의 실행을 담당하는데, 프로세스의 특정 부분을 누가 수행하는가를 결정하는 작업할당 정책이 워크플로우 시스템에 설계 및 구현되어 있어야한다. 여러 조직들의 작업할당에는 매우 다양한 문제들이 있을 수 있어서, 다양한 여러 문제들을 다 포괄하는 하나의 모델을 고안하는 것은 가능하지 않을 것이다. 본 논문에서는 워크플로우 시스템에서의 작업할당 정책에 대한 보편적인 설계 방법으로서, 각 조직에 주어진 임의의 고려할 사항들에서부터 작업할당 정책들을 정의하기 위한 메타 모델 기반 접근 방법을 제시한다.

• 한국안전학회지
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• 제35권5호
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• pp.66-73
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• 2020

The change in labor consciousness began to draw social attention to work-life balance (WLB). The WLB is one of the major factors affecting the health and safety problems of workers. Although shiftwork adversely affects WLB, safety, and health problems of workers, WLB of shift workers has received little empirical attention. The purpose of this study was to examine whether WLB mediates the relationship between shiftwork and shift worker's safety and health problems, participation in leisure activities moderates WLB, and finally, whether WLB moderated by participation in leisure activities mediates the relationship between shift work and shift worker's safety and health problems. For the study, the data of the 5^th wave of Korean Working Condition Survey(KWCS) conducted by Korea Occupational Safety and Health Agency(KOSHA) of South Korea was used. Conditional process analysis revealed that the relationship between shift work and worker's safety and health problems is mediated by WLB; however, participation in leisure activity showed no moderation effect on WLB. Therefore, the moderated mediation effect has failed to achieve statistical significance. The results indicate that working environment improvement in consideration of the WLB is needed to gain shift worker's long-term safety and health. The implications of this study and suggestions for future research were discussed.

• 지역사회간호학회지
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• 제32권3호
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• pp.233-242
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• 2021

Purpose: The purpose of this study was to verify influencing factors affecting service quality provided by caregivers working for the elderly with dementia. Methods: Data were collected using a self-reported questionnaire from 214 caregivers in a long-term care facility in D city. The data were analyzed with service quality, dementia knowledge, work value, and job performance confidence. For data analysis, the descriptive statistics, t-test, one-way ANOVA, Pearson correlation coefficients, and multiple regression were performed using SPSS/WIN 21.0 program. Results: There were significant differences in service quality depending on the health status. Factors influencing service quality were work value, and job performance confidence with R² value of 38%. The highly influencing factors were work value, and job performance confidence. Conclusion: The results of this study indicate that the effort to improve the service quality of caregivers should focus on work value and job performance confidence.

• 대한조선학회논문집
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• 제44권1호
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• pp.48-54
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• 2007

Higher productivity and less cost during the manufacturing process of ships are required to maintain international competitiveness of modern shipbuilding industries. The integrated hull/ outfitting/ painting scheduling(IHOP) process is a final point, where logistics are finally being integrated and upcoming schedules are made. Therefore, more profits are expected from IHOP by effective management. In this thesis, IHOP is proposed in order to solve how to choose block erection date with IHOP scheduling logic. The result of IHOP scheduling is highly advised to utilize fabrication, outfitting shops. A standardized operation and load of resource will eventually be applied in long-term time span point of view for this will make it easy to enable capacity planning and workforce planning. It is also expected to eliminate inefficiency in overtime work and efficiently utilize manpower in short-term.

• The Korean Journal of Ecology
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• 제27권1호
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• pp.9-13
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• 2004

Dams are distributed widely in all over the world. China is one of the countries which have the most dams in the world. The construction of dams promotes consumedly to the development of economy and society, at the same time, brings many ecological and social problems. In China, the landscape ecological changes are caused by the construction of dams. These changes are long term or short term, and some of these changes are positive, others are negative. Solving these issues need do a lot of circumspect work in location choosing, planning and designing, practicing and protection of the up reservoir basin and the whole basin and so on. The construction of dams should be implemented by reasonable landscape planning, ecological environment protection in order to realize sustainable development.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.307-309
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• 2000

This paper presents development of program for mid-tong term load forecasting in region and district respectively. In this program, at first, the region is classified by KEPCO branch which can be analyzed in light of curl·elation between load characteristics and economic indicator and then, prediction for load density in each region was performed by scenario of economic, population and city plan. Secondly, prediction for load density in each district is performed by methodology which is based on land use method. Finally efficiency for prediction work in each KEPCO branch could be identified by applying the developed program to the Seoul city in real.

• 공학교육연구
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• 제19권2호
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• pp.97-101
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• 2016

This paper examines the industry field training education model, analyze the operational status proposed improvement measures. Data were analyzed using a field training participating students participating industry last three years. On the other hand analysis field training participating students increased, industry participation has decreased. And most of the students took part in the seasonal short-term job training. In addition, it was difficult to analyze the employment status field training operations follow-up member. In this paper, a field training operations support system management models and practical training courses organized field trips how to improve. Field training operations support will be strengthened through the work associated with the company expanding participation model introduced and is expected to increase in the long-term practical training, students participate in field training system improvement. Run the job training Improvement in future research presented in this paper attempts to analyze the students' employment status and results of operations involved.