• 한국안전학회지
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• 제27권6호
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• pp.43-47
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• 2012

The unbalance currents flow the High Temperature Superconducting (HTS) power cable caused by asymmetrical fault, harmonic distortion and unbalanced load. That problem causes additional loss and leakage field in the HTS power cable, and deteriorates the electric power quality and stability. In addition, large amounts of unbalanced current can cause negative sequence and ground relays to operate. This paper presents an analysis unbalanced three-phase current distribution in HTS power cable caused by unbalanced load condition and grounding methods using PSCAD/EMTDC. The results obtained through the analysis would provide important data for the design of HTS power cables and valid information for their installation in power system.

• 한국안전학회지
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• 제29권5호
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• pp.47-53
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• 2014

Despite the automatic fire alarm system, according to the national fire data system of national emergency management agency, the fires account for 40,932 incidents, 2,184 injuries and about 430 billion won in property losses in 2013. Since the conventional automatic fire alarm system has several weaknesses related to electrical signal such as noise, surge, lighting, etc. Most fires are mainly caused by electrical faults, mechanical problem, chemical, carelessness and natural. The electrical faults such as line to ground fault, line to line fault, electrical leakage and arc are one of the major problems in fire. This paper describes the development of a novel real-time fire monitoring system algorithm including fault detection function which puts the existing optic smoke and heat detectors for fire detection with current and voltage sensors in order to utility fault monitoring using high accuracy DAQ measurement system with LabVIEW program. The fire detection and electrical fault monitoring with a proposed a new detection algorithm are implemented under several test. The fire detection and monitoring system operates according to the proposed algorithm well.

• 한국안전학회지
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• 제32권6호
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• pp.22-28
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• 2017

According to the National Fire Data System (NFDS), more than 5,000 vehicle fires have occurred every year for the last 10 years. Vehicle fires are primarily caused by mechanical (breaking system and engine), electrical (wiring and battery), and chemical (oil and fuel gas leakage) problems. The electrical factor has increased with the installation of driver convenience equipment. For example, today, the black box is widely used to provide video data recording of motor vehicle accidents. The black box consists of a front camera, rear camera, and wires. The black box wires are directly connected to the junction box or fuse box from the start battery that operates to provide normal on power supplying for engine stop. It is extremely dangerous when the wires short circuit due to insulation aging, mechanical and electrical stress, etc. In this study, the black box wiring fire risk have been analyzed and investigated when the steady state and abnormal operations, and under the following conditions: wiring arrangements with a high temperature condition, insulation aging, poor contact, and short circuits. The results showed that black box wiring short circuits had a higher fire risk than the other fire hazard elements. To prevent fire hazards caused by black box wiring, the black boxes must be installed by qualified service personnel. Do not modify the wiring, remove the fuse and secure the wiring using cable ties or insulation tape.

• 한국안전학회지
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• 제34권6호
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• pp.13-21
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• 2019

Leakage accidents in businesses dealing with hazardous chemicals can have a great impact on the workers inside the workplace, as well as residents outside the workplace. In fact, there were cases where hazardous chemicals leaked from many businesses. As a result, the Chemicals Control Act(CCA) was enacted in 2015, the Ministry of Environment introduced an Off-site Risk Assessment(ORA). The purpose of the ORA is to secure safety from the installation of the design of the workplace facilities so that chemical accidents of hazardous chemical handling facilities do not cause human or physical damage outside the workplace. In general, the ORA qualitatively determines where a protected facility is within the scope of the accident scenario. However, elderly who belong to the sensitive group is more sensitive than the general group under the same chemical accident effect, and the extent of the damage is serious. According to data from the Korea National Statistic Office, the number of elderly people is expected to increase steadily. Therefore, a quantitative risk analysis considering the elderly is necessary as a result of a chemical accident. In this study, accident scenarios for 14 locations were set up to perform emergency evacuation due to toxic gas leakage of Cl₂(Chlorine) and HF(Hydrogen Fluoride), and the effects of exposure were analyzed based on the evacuation velocity difference of age 20s and 60s. The ALOHA(Areal Locations of Hazardous Atmospheres) program was used to calculate the concentration for assessing the effects. The time of exposure to toxic gas was calculated based on the time it took for the evacuation to run from the start point to the desired point and a methodology was devised that could be applied to the risk calculation. As a result of the study, the relative risk of the elderly, the sensitive group, needs to be determined.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.544-547
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• 2003

The owner of water pipeline has a burden of responsibility for the protection of corrosion and the prevention against leakage of water. So, they have been installed a CP(Cathodic Protection) System in odor to protect corrosion. And they also have been measured and analyzed the data about P/S(Pipe to Soil) potential of water pipeline. The P/S potential is basic data of evaluation for water pipeline corrosion. They need remote automatic corrosion monitoring system for easy maintenance. In this paper, The communication method was studied mainly. And the specifications of proposed TRS (Truncked Radio System ) terminal for corrosion monitoring are introduced briefly.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 B
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• pp.637-640
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• 2003

The owner of water pipeline has a burden of responsibility for the protection of corrosion and the prevention against leakage of water. So, they have been installed a CP(Cathodic Protection) System in oder to protect corrosion. And they also have been measured and analyzed the data about P/S(Pipe to Soil) potential of water pipeline. The P/S potential is basic data of evaluation for water pipeline corrosion. In this paper, results of development about remote wireless corrosion monitoring system for water pipe line are presented briefly.

• 한국안전학회지
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• 제33권5호
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• pp.141-149
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• 2018

In a PCB factory, there is a corrosive chemical substance supply system that can causes major leakage accidents. These accidents can give rise to shut down the factory and do residents damage that cause enormous loss of properties. To mitigate these risks, it is necessary to provide a chemical disaster prevention system. Moreover, after considering the situation and environment of the production site, it is of great importance to build an optimal chemical accident prevention system by reflecting risk reduction measures from the point of process design and by assessing quantitative risk based on reliability data. However, because there was no established database of the reliability about facilities and equipment that can be used in the domestic, the business site and consulting organization had being used the reliability data such as USA CCPS(Center for Chemical Process Safety). In these days, Korean institutes are studying on reliability data utilization method of quantitative risk assessment for preventing chemical accidents and domestic utilization algorithms and storage bed of reliability data. This study presents samples of reliability database about the chemical substance supply system that constructed from the history data such as failure, maintenance for 10 years at a PCB factory. Also, this work proposes the safety design criteria for supply facilities of corrosive chemical substance by assessing quantitative risk on the basis of the reliability data.

• 정보보호학회논문지
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• 제25권6호
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• pp.1435-1447
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• 2015

금융회사에서는 내부자에 의한 개인정보유출 방지 및 내부통제 강화를 위하여 E-DRM(Enterprise-Digital Right Management), 개인정보검색, DLP(Data Loss Prevention), 출력물보안, 인터넷 망 분리시스템, 개인정보모니터링 시스템 등의 보안 솔루션을 도입 운영하고 있다. 하지만 개인정보유출 사고는 계속해서 발생하고 있으며, 이 기종 보안 솔루션간의 독립적인 로그 체계로 인하여 개인정보문서의 회사 내부유통 및 외부반출 관련한 정합성 있는 유통경로의 연관 분석이 어렵다. 본 논문은 보안문서를 기반으로 하여 업무시스템 및 이 기종 보안 솔루션간의 로그를 유기적으로 정합성 있게 연관 분석할 수 있는 연결고리 체계 방안을 제시하고, 업무시스템을 통하여 개인PC에 생성되는 보안문서나 개인이 작성한 보안문서에 대한 Life-Cycle 관리방안 및 개인정보가 포함된 보안문서에 대한 유통경로 추적을 위한 효율적인 탐지 방안을 제안하고자 한다.

• 정보보호학회논문지
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• 제26권2호
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• pp.369-375
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• 2016

기업 대부분은 사업 연속성을 위협하는 기밀정보 유출을 방지하기 위해 DRM, 메일 필터링, DLP, USB 보안 등 다양한 보안 시스템 구축에 투자를 아끼지 않고 있다. 그러나, 기업이 기밀정보의 유출 및 관련 사건을 인지한 시점에는 해당 직원이 이미 '퇴직'해 인사적 조치가 어렵고 관련 증거도 퇴직과 함께 사라져 버리는 경우가 많다. 그런 측면에서 퇴직 징후를 미리 탐지하고 사전 조치를 하는 것은 매우 중요하다. 데이터의 최소 단위인 파일을 대상으로 이루어지는 사용자 행위를 기록하는 DRM 로그를 활용하면, 퇴직 예측이 장 단기적으로 가능하므로 유출 행위를 예방하고 사후 증적으로도 활용할 수 있다. 이 연구는 직원의 퇴직 징후를 예측해 사전에 모니터링하는 프로세스를 수립함으로써, 퇴직자의 기밀 유출로 인한 기업 손실을 최대한 방지할 수 있는 방안을 제시한다.

• 한국멀티미디어학회논문지
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• 제14권2호
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• pp.228-237
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• 2011

정보보호의 패러다임 진화와 함께 데이터베이스에 저장된 증요 데이터의 유출이나 도난의 위험성이 증가되고 있으며 실제로 개인정보의 대량 유출 사건이 끊임없이 발생하고 있어 데이터베이스 보안에 대한 요구사항이 매우 높아지고 있다. 기업 내부 정보 유출방지를 위하여 개발된 기술은 관리자의 정책 설정 및 허가된 사용자만이 DBMS 접속 권한을 갖게 되는 수동적인 제어 방식으로 완벽하게 보호하기에는 기술적인 제약이 따르고 있다. 이에, 본 논문에서는 데이터베이스에 핵심 정보에 접근하는 중요 Query에 대하여 파싱하고, 인터럽트하여 결제함으로써 데이터베이스 시스템을 적극적으로 보호하고 획일적 보안 정책을 적용할 수 있는 데이터베이스 보호를 위한 Query 결재 시스템을 제안한다.