• 한국환경농학회지
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• 제39권4호
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• pp.343-351
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• 2020

BACKGROUND: Irrigation water is known to be one of the major sources of bacterial contamination in agricultural products. In addition, anti-microbial resistance (AMR) bacteria in food products possess serious threat to humans. This study was aimed at investigating the prevalence of foodborne bacteria in irrigation water and evaluating their anti-microbial susceptibility. METHODS AND RESULTS: Surface water (n = 66 sites) and groundwater (n = 40 sites) samples were collected from the Gyeongi and Gangwon provinces of South Korea during April, July, and October 2019. To evaluate the safety of water, fecal indicators (Escherichia coli) and foodborne pathogens (E. coli O157:H7, Salmonella spp., and Listeria monocytogenes) were examined. E. coli isolates from water were further tested for antimicrobial susceptibility using VITEK2 system. Overall, detection rate of foodborne pathogens in July was highest among three months. The prevalence of pathogenic E. coli (24%), Salmonella (3%), and L. monocytogenes (3%) was higher in surface water, while only one ground water site was contained with pathogenic E. coli (2.5%). Of the 343 E. coli isolates, 22.7% isolates were resistant to one or more antimicrobials (ampicillin (18.7%), trimethoprim-sulfamethoxazole (7.0%), and ciprofloxacin (6.7%)). CONCLUSION: To enhance the safety of agricultural products, it is necessary to frequently monitor the microbial quality of water.

• 디지털산업정보학회논문지
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• 제18권2호
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• pp.39-48
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• 2022

The application of digital technology to instrumentation and control systems in nuclear power plants has overcome many shortcomings of analog technology, but the threat of cybersecurity has increased. Along with other systems, the reactor protection system also uses digital-based equipment, so responding to cybersecurity threats is essential. We generally determine cybersecurity threats according to the role and function of the system. However, since the instrumentation and control system has various systems linked to each other, it is essential to analyze cybersecurity threats together between the connected systems. In this paper, we analyze the cybersecurity threat of the reactor protection system with the associated facilities. To this end, we quantitatively identified the risk of the reactor protection system by considering safety functions, a communication type, the use of analog or digital-based equipment of the associated systems, and the software vulnerability of the configuration module of the reactor protection system.

• Journal of Electrical Engineering and Technology
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• 제12권5호
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• pp.2079-2087
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• 2017

As the number of tall buildings is increasing, the high-speed lift is necessary in the modern world. Therefore, the further considerations for associated safety devices of lifts were required by the International Standards. In order to stop the moving of cage and keep it, the lifts have to be provided with means that can detect the unintended car movement. Therefore, the International Standard Safety Rules for the construction and installation of lifts had been revised. This paper describes the operation principles of the Rope Brake to fit the Unintended Car Movement Protection (UCMP) means required by the International Standards. This paper confirmed that the performance of these devices was suitable in the scope of the safety standards. This paper also analyzed that the shocks on working of these devices in a car would be dangerous to each passenger differently. Thus, this paper proposes a new design that the circuit diagram of the Unintended Car Movement Protection systems should be improved from the existing design to solve these internal shock problems. So, it is expected to protect passengers from the internal shocks by working of Rope Brake due to irrelevant factors.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.201-203
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• 2001

Safety is emphasized in nuclear power plant system for its characteristic. One of the most important systems to guarantee the safety of nuclear power plant is the PPS(Power protection system). The measurement control system includes PPS, which is similar to the human nervous system, is very important factor not only for the safety but also for the operation. Therefore, developing a technology to level up the performance of measurement system and reliability of the plant will bring cost-effective and safe generation of nuclear power. In this study, I researched composition of digitized PPS and algorithm for cyclic inspection.

• Journal of Radiation Protection and Research
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• 제35권4호
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• pp.142-150
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• 2010

중수로 사용후핵연료의 처분 효율을 높이기 위하여 새롭게 제안된 처분 시스템에 대한 방사선량을 MCNPX를 사용하여 계산함으로써 이 시스템의 방사선 안전성을 예비적으로 평가하고자 하였다. 이를 위해서 처분시스템의 각 요소에 대한 구성, 제원, 재질 등을 분석하였으며, 그에 상응하는 모델링을 수행하였다. 선량평가는 주요 구성요소에 대하여 수행하였으며, 평가결과 내부 구성요소에 대해서는 방사선량이 높은 편이었으나, 최종적인 처분시스템은 방사선에 대한 안전성이 높은 것으로 나타났다.

• 항공우주시스템공학회지
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• 제14권6호
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• pp.79-84
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• 2020

Cooler driver electronics (CDE) for maintaining low temperature of the satellite payload IR sensor consists of a compressor that has a pulsation current load condition when it is operated. This pulsation current produces large voltage fluctuation, which affects both load and regulated bus stability. Thus, CDE power conditioning system consists of a primary bus, infrared power distribution unit for battery charging and protection, reverse current protection diode, and battery, which is used as a buffer. In this study, the operational mode analysis is performed by each part with equivalent impedance modeling verified through system level simulation. From this mode analysis, the safety margin for state of charge and open circuit voltage of the battery is determined for satisfying the minimum operational voltage of the CDE load.

• 한국안전학회지
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• 제33권6호
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• pp.8-14
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• 2018

Recently, serious problems occurred such as insecticide eggs, sanitary pads with carcinogens, radon(Rn) emitting beds in domestic. It had not been establishing the inspection system to evaluate safety and human harmfulness before occurring real accidents. This research was conducted to test preliminary experimental inspection for consideration of safety insensibility. The influence of corrosion of metals and plants was studied through aerosol type spraying of agricultural pesticide products coming into the market. These products contain primary three insecticide ingredients(Flufenoxuron, Etoxazole, Fipronil) in recent accidents. Visual examination, SEM-EDS and optical microscope were used for the analysis for corrosion effect. Results show that a lot of ingredients contain in the crop protection products, and various type of corrosion exist in the surface of metals and plants. Therefore, it is necessary to provide health warning and accurate range of use for crop protection products containing insecticide ingredients.

• Journal of Radiation Protection and Research
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• 제26권3호
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• pp.255-263
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• 2001

An Orphan Sources Control program controlled by a web based information system in Korea has been developed to satisfy the national demand on a total management of and integrated radiation safety. There are, currently, three approaches going on to control and manage the orphan sources in Korea. First, Korean regulatory authority has been conducting scrutinizing investigation on and thoroughly monitoring the possession of unlicensed radioactive sources from the late 1990s. Second, the regulatory authority will fully operate an information system on radiation safety to effectively trace and monitor all radioactive sources in the country by the mid 2001. Finally, the regulatory authority strongly advises steel mill companies to closely scrutinize and inspect the scrap metals when they attempt to reutilize metals to prevent from being contaminated by uncontrolled sources through the scrap monitoring systems.

• 한국전기전자재료학회논문지
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• 제32권3호
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• pp.256-261
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• 2019

The use of military lithium batteries in this field accelerates the generation of internal pressure because the active materials, lithium and the electrolyte, react to form sulfur dioxide gas. This also reduces the amount of electrolyte. In this condition, batteries can 'vent' or 'explode' especially when completely discharged. Such venting and explosion can be regarded as a safety accident, as toxic gases and shrapnel are ejected from the batteries which can harm the user. A DTaQ was carried out in 2017 as a quality problem solution project to solve this safety issue. A protection circuit was thereby developed, which included a micro controller unit (MCU) which can stop battery usage when in an over-discharging state by sensing its low-voltage condition. In 2018, this concept was expanded to lithium batteries for the remote controlled ammunition system. This paper reports results of the improved performance.

• 한국재난정보학회 논문집
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• 제19권4호
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• pp.844-850
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• 2023

연구목적: 본 논문은 백열전구를 이용하여 단락보호 전원공급 장치를 개발하고, 이를 학습 교구로 활용하는 연구에 관한 것이다. 전기 안전과 에너지 절약을 동시에 고려한 이 연구는 교육과 산업 분야에서 중요한 응용 가능성을 가지고 있다. 백열전구를 활용한 단락보호 전원공급 장치는 기존의 전원공급 장치와 비교하여 안전성과 효율성을 향상시키는데 도움이 되며, 학습 교구로 학습자들에게 전기 안전 교육을 제공함으로써 실생활에서의 전기 안전 지식을 습득하는데 기여한다. 연구방법: 백열전구를 사용하여 단락보호 전원공급 장치를 개발하고 개발된 장치의 성능 평가 및 안전성 확인을 통해 학습 교구로 활용할 수 있는 새로운 전원공급장치를 제작 한다. 결론:백열전구를 활용한 단락보호 전원공급 장치의 개발과 학습 교구로의 응용 가능성을 탐구한 연구이다. 이를 통해 전기 안전과 에너지 절약에 기여할 수 있는 혁신적인 솔루션을 제시하였으며, 교육 분야와 산업 분야에서의 응용 가능성을 열어놓았다. 이러한 연구는 전기 안전 및 에너지 관리 분야에서의 연구와 교육에 기여할 것으로 기대된다.