• Biomolecules & Therapeutics
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• 제4권3호
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• pp.271-274
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• 1996

The antihepatotoxic activity of Bezoar Bovis and Moschus was investigated by in vitro assay method using galactosamine and carbon tetrachloride-induced cytotoxicity in primary-cultured rat hepatocytes. The antihepatotoxic activity was evaluated by measuring the level of glutamate pyruvate transaminase and sorbitol dehydrogenase which were released from the necrotic hepatocytes to the culture medium. In galactosamine-intoxicated hepatocytes, the chloroform fraction of Bezoar Bovis reduced the level of glutamate pyruvate transaminase and sorbitol dehydrogenase resulting in 65% and 59% protection, respectively. The n-Hexane fraction of Moschus resulted in 45% and 40% protection, respectively in this system. In the case of carbon tetrachloride-intoxicated rat hepatocytes, Bezoar Bovis did not have significant effect and only the aqueous fraction of Moschus showed 42% and 40% protection, respectively.

• 융합보안논문지
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• 제19권4호
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• pp.3-12
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• 2019

방위산업기술의 유출은 해당 기업의 영업 손실뿐만 아니라 국가안보 및 국익 차원에서도 심각한 피해를 야기할 수 있다. 최근 정부는 방위산업기술의 중요성을 인식하여 방위산업기술보호법을 제정하였고, 그에 따른 방위산업기술 보호지침을 마련하였다. 법규에 따르면 방위산업기술을 보유한 기관 및 업체는 방위산업기술 보호체계를 구축해야 하며, 정부는 이들의 기술보호 수준 향상을 위해 다양한 기술보호 정책을 수립하고 추진해야 한다. 본 연구에서는 기존의 기술보호지침에 대한 비교를 통해 시사점을 도출하고 방위산업기술 보호지침의 자가진단 항목을 대상으로 AHP 기법을 통해 보호체계 세부항목에 대한 우선순위 분석을 하였다. 이를 통해 대상기관에 대한 보호수준의 효율적 진단과 보호체계의 체계적인 구축을 위한 정책 지원이 가능할 것으로 기대된다.

• 한국항행학회논문지
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• 제15권4호
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• pp.510-516
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• 2011

위성항법시스템(GNSS)을 민간항공 분야에 활용하기 위해서는 국제민간항공기구(ICAO)가 정한 비행단계별 정확성(Accuracy), 무결성(integrity), 연속성(continuity), 가용성(availability) 성능요구조건을 만족시켜야 한다. 사용자의 무결성을 확보하기 위해서는 사용자의 보호 수준을 크게 잡아야 하고 가용성을 향상시키기 위해서는 보호수준이 작을수록 좋다. 따라서 주어진 항행요구조건을 만족하기 위해서는 사용자의 무결성을 확보하면서 보호수준을 최대한 작게 잡아야 한다. 본 논문에서는 한국형 광역보정시스템 테스트베드 중앙처리국 모듈의 현재까지 진행 상황에 대해서 설명하고 현재 사용되고 있는 무결성 관련 알고리듬을 적용하였을 때 사용자의 무결성 및 가용성 성능에 대한 예측을 수행하였다. 또한 항법위성의 궤도 및 시계오차에 대한 공분산 행렬을 사용자 무결성 감시에 적용하였을 때의 가용성 향상 정도를 시뮬레이션을 통해 예측하도록 한다.

• 전기학회논문지
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• 제60권1호
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• pp.36-42
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• 2011

This paper mainly proposes the protective coordination scheme of the microgrid system. The microgrid protection is identical to the conventional protection system separating the normal part and contingency part to reduce damage when the contingency occur at power cables, facilities. But they are different in the protection type. The conventional protection system only considers unidirectional current. However the microgrid protection should be considered not only unidirectional current but also backfeed current because various microsources and loads are installed in the microgrid system. In case the contingency occurs in microsource, when microgrid is interconnected to grid, the protection system should be configured to not separate microgrid from grid before the microsource is isolated to microgrid. And in case of fault occur in power system, the microsources should not isolated to microgrid before the static switch at PCC is tripped to separate from power system. Considering these characteristic of microgird, this paper proposes the protective coordination scheme of microgrid and implemented the on-line real time monitoring system. Especially in case the microgrid is connected to low voltage distribution system with 220/380V voltage level, the proposed protection method with power IT technology can solve the problems when the existing protective devices only applied to the microgrid system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.545-546
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• 2015

Arc flash hazard study is required for the electric power system of industrial plant nowadays. Arc flash incident energy and level are calculated by arc flash hazard study. The arcing fault clearing time is determined by the response time of protection devices. This paper is protection devices coordination study to reduce potential incident energy for industrial electric power system.

• Journal of Radiation Protection and Research
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• 제14권2호
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• pp.51-62
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• 1989

The high efficiency moderated-type neutron spectrometer and doseequivalent counter were developed for the measurement of low level environmental neutrons. By using these detectors, the neutron energy spectra and dose equivalent rates due to skyshine effect were measured in the environment surrounding the accelerator facilities and also the altitude variation of cosmic ray neutrons in the aircraft flying over Japan.

• Journal of Positioning, Navigation, and Timing
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• 제11권4호
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• pp.317-325
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• 2022

In this paper, we developed a single frequency-based RRAIM to monitor integrity of the UAM landing vertically in urban area with only low-cost single-frequency GPS receiver. Conventional dual-frequency RRAIM eliminates ionospheric delay through a combination of frequencies. In this study, ionospheric delay was directly modeled. Drift error of residual ionospheric delay is modeled using the previously studied result on ionospheric rates of change. To verify the performance of the proposed RRAIM algorithm, a simulation of vertical landing UAM in urban area was conducted. It was assumed that the protection level at the initial position was calculated through SBAS correction data. During vertical landing, integrity monitored by receiver alone without external correction data. In the 60 sec simulation, the protection level of the proposed RRAIM compared to the conventional RRAIM was calculated to be 140% due to the accumulated ionospheric delay error. Nevertheless, it was confirmed that the final vertical protection level meeting the requirements of LPV-200, which cannot be achieved with single frequency GPS receiver alone.

• 한국군사과학기술학회지
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• 제24권3호
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• pp.339-347
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• 2021

Recently, the incidence of lightning in Korea has been increasing more and more. The damage caused by lightning is also getting worse. Lightning protection system is a prerequisite, not a sufficient condition. Considering the characteristics of lightning, there is a high frequency of lightning strikes in highlands. So, high grades of LPS should be applied to ground facilities of anti-aircraft weapons systems. 4-Level LPS was applied on groung facilities of anti-aircraft weapons system based on lightning incidence rate in past. There are some possibilities of damage from lightning in anti-aircraft weapons system. So, we have to readjust the LPS level with grounding, lightning rods and surge protect device based on lightning incidence rate in now days. Propose 2-level LPS and design with lightning rods, surge protector, separated grounding in this paper.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.606-609
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• 1997

Technology in fire sprinklers has exploded. There is more private fire sprinkler research now than ever before. New technology in fire sprinklers has tested the existing standard and found that it was wrong in some cases, it has provided new sprinklers that control fire better while reducing the cost of the overall system. This expansion of the types and applications of fire sprinklers has created a great need for education for the Authorities Having Jurisdiction and the Engineer as they must be able to make informed decisions regarding this new technology. Significant research has been done at Factory Mutual Research Corporation and Underwriters Laboratory in the United States. Full scale fire testing is done to prove any new technology did not lower the level of protection of existing fire sprinkler system installations. In each and every case, the existing level of fire protection was the baseline against which the new sprinklers were tested. This level can not be lowered for the test to be considered a success. This is intended to be an overview of the developments in fire sprinklers. Although extensive detail is not included, the overall aspects of these developments can be discussed. The research that will be covered will include the following general subjects: high piled and rack storage sprinkler protection without in-rack sprinklers, extended coverage and quick response sprinklers for ordinary and light hazard occupancies, as well as special sprinklers and their applications.

• 동서간호학연구지
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• 제29권1호
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• pp.24-32
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• 2023

Purpose: This study aims to examine level of perception and performance of privacy protection behavior of anesthesia and operating room (OR) nurses for patients who underwent general anesthesia surgery. Methods: Data collection was conducted from August 2020 to January 2021 for a total of 101 participants, consisting of 49 patients and 52 nurses. Independent t-test and Pearson's correlation were conducted using SPSS 21. Results: Anesthesia and OR nurses showed the highest score in patient privacy, followed by patient information management, body privacy, and the lowest score in communication. There was a significant difference between the patient information and the communication. Conclusion: Anesthesia and OR nurses had the highest level of perception and performance of patient privacy protection behavior for body privacy, and the lowest for communication. In addition, there was a significant difference in patient information management and communication. In order to protect the privacy of patients undergoing general anesthesia surgery, efforts are needed to learn standardized nursing knowledge, attitudes, and practice.