• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6161-6164
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• 2014

Background: We have reported the radiation could activate STAT3, which subsequently promotes the invasion of A549 cells. We here explored the dose- and time-response of STAT3 to radiation and the effect of radiation on upstream signaling molecules. Materials and Methods: A549 cells were irradiated with different doses of ${\gamma}$-rays. The expression of and nucleus translocation of p-STAT3 in A549 cells were detected by immunoblotting and immunofluorescence, respectively. The level of phosphorylated EGFR was also assessed by immunoblotting, and IL-6 expression was detected by real time PCR and ELISA. Results: Radiation promoted the phosphorylation of STAT3 at Y705 in a dose- and time-dependent manner and nuclear translocation. The level of phosphorylated EGFR in A549 cells increased after radiation. In additional, the mRNA and protein levels of IL-6 in A549 cells were also up regulated by radiation. Conclusions: STAT3 is activated by radiation in a dose-and time-dependent manner, probably due to radiation-induced activation of EGFR or secretion of IL-6 in A549 cells.

• Nuclear Engineering and Technology
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• v.56 no.7
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• pp.2534-2544
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• 2024

This paper proposes a flooding safety system (FSS) and its operation strategy that can provide long-term safety and effective maintenance for modules of small modular reactor (SMR) and metal containment maintained at dried environment during normal operation. During hypothesized accidents, the FSS re-collects the evaporated steam into the common pool by the condenser installed above the common water pool and provides an emergency coolant for the cavities and auxiliary pools. This study suggested that the condensate re-collection strategy using the FSS can effectively delay the depletion of available water in response to the accidents. Without recollection, the achievable grace periods ranged from 44 to 1507 days for six-module and one-module accidents, respectively. However, with a full re-collection (ratio = 1.0), the time to total depletion of emergency coolant was estimated indefinite. Even with a partial re-collection ratio of 0.3, a grace period of 83.5 days could be ensured for a six-module transient. This study reported the effectiveness of condensate re-collection and the FSS as an innovative safety management strategy and system. Employing a condensate re-collection strategy with a high re-collection ratio can enhance the long-term safety and effective convenience of SMR operations and maintenance.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.481-486
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• 1996

Safety management may be classified into three dimensions: (1) risk management, (2) accident management, and (3) emergency management. This paper addresses the recent trends of safety management in nuclear industry, focussing on risk management and accident management.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1660_1661
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• 2009

The excitation system for nuclear emergency diesel generator has been developed and is commercially operating now. The characteristics are triple modular redundant controllers, double redundant rectifiers and digital system, comparing the existing(and removed) system.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.435-440
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• 1996

Large Loss-of-Coolant Accidents analyzed in Final Safety Analysis Reports are usually covered by Reactor Inlet Header. Reactor Outlet Header and Primary Pump Suction breaks as representative cases. In this study we analyze the total (guillotine) break of an Emergency Core Cooling System (ECCS) pipe located at the ECCS injection point into the Primary Heat Transport System (PHTS). It was expected that thermal-hydraulic behaviors in the PHT and ECC systems are different from those of a Reactor Inlet Header break, having an equivalent break size. The main purpose of this study is to get insights on the differences occurred between the two cases and to assess these differences from the phenomenon behavior point of view. It was also investigated whether the ECCS line break analysis results could be covered by header break analysis results. The study reveals that as the intact loop has almost the same behavior in both analyzed cases. broken loop behavior is different mostly regarding sheath temperature in the critical core pass and pressure decrease in the broken Reactor Inlet Header. Differences are also met in the ECCS behavior and in event sequences timings.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.909-916
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• 2022

To study the developments and variations of unsafe behaviors in nuclear power plants thus reduce the possibility of human-related accidents, this paper, based on the Game Theory, focused on the changes in benefits of the Department of Management, Operational and Emergency in a nuclear power plant, and established the expected revenue functions of these departments. Additionally, the preventive measures of unsafe behaviors in nuclear power plants were also presented in terms of these 3 departments. Results showed that the violations of the Operation Department (OD) and the Emergency Department (ED) were not only relevant with the factors such as their own risks, costs, and the responsibility-sharing due to accidents, but also affected by the safety investments from the Management Department (MD). Furthermore, results also showed that the accident-induced responsibility-sharing of both the OD and the ED would rise, if the MD increased the investments in safety. As a result, the probability of violation behaviors of these 3 departments would be attenuated consciously, which would reduce the unsafe behaviors in the nuclear power plants significantly.

• Journal of IKEEE
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• v.23 no.2
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• pp.667-674
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• 2019

The recent incidents of Nuclear Power Plant(NPP) gave rise to a total power outage caused by the loss of the functions of the off-site and the emergency power supply. Currently, emergency power supply of NPP have been taken into account by Li-ion batteries instead of existing lead-acid batteries. In order to judge the applicability of the cylindrical Li-ion battery, it is necessary to analysis the results of various electrical tests. This paper investigates the basic electrical characteristics test of three types of cylindrical batteries in order to select the most suitable battery and estimate state of battery through equivalent circuit model and propose method to solve the problem.

• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.453-464
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• 2001

A commercial nuclear power station contains at least tow emergency diesel generators(EDG) to control the risk of severe core damage during station blackout accidents. Therefore, the reliability of the EDG's to start and load-run on demand must be maintained at a sufficiently high level. Probabilistic safety assessments(PSA) are increasingly being used to quantify the public risk of operating potentially hazardous systems such as nuclear power reactors. In this paper, to perform PSA, we will introduce three different types of data and use Bayes procedure to estimate the error rate of nuclear power plant EDG, and using practical examples, illustrate which method is more reasonable in our situation.

• The Korean Journal of Emergency Medical Services
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• v.22 no.1
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• pp.83-97
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• 2018

Purpose: The purpose of this study was to provide basic data for the development of personal protective equipment (PPE) for emergency medical technicians (EMTs) during chemical, biological, radiological, nuclear, and explosive situations. Methods: Body measurements were obtained for adults aged from 20 to 59 years from the data in the 6 th Size Korea national sizing survey. These data were compared to the sizes of protective clothing currently available in the market. In-depth interviews with active paramedics with experiences of wearing PPE were conducted. Results: Most of the imported protective clothing turned out to be unfit for Korean adults. This showed the urgent need for developing appropriately sized protective clothing for Korean emergency technicians. In total, 55.0% of the respondents indicated that the current protective clothing is unsafe, and 71.0% requested the clothing to have level C protective performance. Regarding the design, many people wanted hooded all-in-one type of clothing. Conclusion: Considering these requirements, most of the wearers wanted their protective clothing to be fundamentally protective of their body, be available in various sizes with adjustable parts, and easy to wear and take off. They also wanted the clothing to be secure in clear sight, while not revealing any parts of their body and not interfringe with their ability to communicate with others.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.632-637
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• 2017

Even though the potential for an accident in nuclear power plants is very low, multiple emergency plans are necessary because the impact of such an accident to the public is enormous. One of these emergency plans involves a robotic system for investigating accidents under conditions of high radiation and contaminated air. To develop a robot suitable for operation in a nuclear power plant, we focused on eliminating the three major obstacles that challenge robots in such conditions: the disconnection of radio communication, falling on uneven floors, and loss of localization. To solve the radio problem, a Wi-Fi extender was used in radio shadow areas. To reinforce the walking, we developed two- and four-leg convertible walking, a floor adaptive foot, a roly-poly defensive falling design, and automatic standing recovery after falling methods were developed. To allow the robot to determine its location in the containment building, a bar code landmark reading method was chosen. When a severe accident occurs, this robot will be useful for accident condition monitoring. We also anticipate the robot can serve as a workman aid in a high radiation area during normal operations.