• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.651-659
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• 2008

Autoreclosing techniques have been used in power systems to maintain system stability and continuity of supply. Environmental and economical issues have driven significant increases in the development of distributed generation (DG). DG connected to distribution systems, however, may impose negative influences with respect to power quality, protection, and stability, because DG can cause some challenges to protection, especially to reclosing. For this reason, in order to improve the reliability and safety of the distribution system, the rules and guidelines suggest that the DG system needs to be rapidly disconnected from the system before reclosing. We present, in this paper, an adaptive reclosing algorithm considering the DG. The algorithm consists of an angle oscillation's judgment, the emergency extended equal-area criterion (EEEAC), the calculation of an optimal reclosing time, and a reconnection algorithm. Our simulation results for three different DG technologies with Electromagnetic Transient Program (EMTP) indicate that we can maintain transient stability while the DG is protected against disturbances.

• International Journal of Reliability and Applications
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• 제12권2호
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• pp.79-94
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• 2011

Redundancy-reliability allocation problems in multi-stage series-parallel systems are addressed in this study. Fuzzy programming techniques are proposed for finding satisfactory solutions. First, a multi-objective programming model is formulated for simultaneously maximizing system reliability and minimizing system total cost. Due to the nature of uncertainty in the problem, the fuzzy set theory and technique are used to convert the deterministic multi-objective programming model into a fuzzy nonlinear programming problem. A heuristic method is developed to get satisfactory solutions for the fuzzy nonlinear programming problem. A Pareto optimal solution is found with maximal degree of satisfaction from the interception area of fuzzy sets. A case study that is related to the electronic control unit installed on aircraft engine over-speed protection system is used to implement the developed approach. Results suggest that the developed fuzzy multi-objective programming model can effectively resolve the fuzzy and uncertain problem when design goals and constraints are not clearly confirmed at the initial conceptual design phase.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.125-128
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• 1990

A program for the protection coordination of distribution systems is reported. The developed program nailed DISCO, consisting of two modules has a capability of selling the overcurrent relays, reclosers, sectionalizers, fuses which are commonly used in the primary feeder systems. Setting is performed in a downstream fashion starting from the substation, and coordination rules are applied identifying the pattern of the primary-backup devices based on the depth-first search. T/C curves of various devices are handled by digitization for accuracy and various graphics and windows are adopted for user-friendly interface.

• 한국IT서비스학회지
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• 제22권6호
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• pp.1-15
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• 2023

This study compares and analyzes the legal systems of Korea, the European Union, China, and the United States based on the disclosure principles and processing policies for personal data processing and provides references for seeking improvements in our legal system. Furthermore, this research aims to suggest institutional implications to overcome data transfer limitations in the upcoming digital economy. Findings on a comparative analysis of the relevant legal systems for disclosing privacy policies in four countries showed that Korea's privacy policy is under the eight principles of privacy proposed by the OECD. However, there are limitations in the current situation where personal information is increasingly transferred overseas due to direct international trade e-commerce. On the other hand, the European Union enacted the General Data Protection Regulation (GDPR) in 2016 and emphasized the transfer of personal information under the Privacy Policy. China also showed differences in the inclusion of required items in its privacy policy based on its values and principles regarding transferring personal information and handling sensitive information. The U.S. CPRA amended §1798.135 of the CCPA to add a section on the processing of sensitive information, requiring companies to disclose how they limit the use of sensitive information and limit the use of such data, thereby strengthening the protection of data providers' rights to sensitive information. Thus, we should review our privacy policies to specify detailed standards for the privacy policy items required by data providers in the era of digital economy and digital commerce. In addition, privacy-related organizations and stakeholders should analyze the legal systems and items related to the principles of personal data disclosure and privacy policies in major countries so that personal data providers can be more conveniently and accurately informed about processing their personal information.

• 디지털융복합연구
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• 제10권3호
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• pp.23-37
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• 2012

불법적인 게임 플레이어들의 해킹 및 악성코드의 유포로 온라인게임은 고객의 개인정보 유출을 빈번하게 일어나게 하는 요인이 되고 있다. 그러므로, 온라인게임사도 게임 개발과 함께 서비스를 운영함에 있어 개인정보보호에 대한 표준화된 체계와 운영의 필요성이 크게 고려되어야 한다. 온라인 게임사별로 정보보호인증을 도입하고 인증 심사를 받고 있으나, 전반적으로 자산이나 물리적, 시스템적 보안에 중점을 두기 때문에 개인정보보호와 관련되어 좀 더 전문적인 체계가 필요하다. 본 연구는 ISO27001, KISA의 ISMS, GMITS 등 기존의 정보보호인증들과 산발적으로 운영되고 있는 개인정보보호인증마크(ePrivacy), 온라인게임 개인정보보호 가이드, BS10012 등 개인정보보호 관련 체계들을 수집하여 분석하였다. 이를 이용하여 온라인게임업체에서 운영 시 필요한 개인정보보호체계 프로세스와 각 단계별로 필요한 점검 항목을 도출하여 개인정보보호 수준을 측정하는 체계적인 도구를 제안하였다.

• 산업경영시스템학회지
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• 제37권2호
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• pp.77-84
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• 2014

The purpose of this research is to identify and develop technology protection plans for small and medium-sized enterprises (SMEs) by analyzing past technology leakage patterns which were experienced by SMEs. We identified factors which affect the technology leakage, and analyzed patterns of the influences using a data mining algorithms. A decision tree analysis showed several significant factors which lead to technology leakage, so we conclude that preemptive actions must be put in place for prevention. We expect that this research will contribute to determining the priority of activities necessary to prevent technology leakage accidents in Korean SMEs. We expect that this research will help SMEs to determine the priority of preemptive actions necessary to prevent technology leakage accidents within their respective companies.

• Journal of international Conference on Electrical Machines and Systems
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• 제2권4호
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• pp.405-412
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• 2013

This paper includes new protection concepts and practices to avoid mechanical damage of three-phase transformer by asynchronous operation of synchronous generator. this failure is often caused just after synchronous generator was connected to the grid because of a malfunction of the controller or misconnections of the synchronous devices. The results of the studies on the analyzing the phenomenon of asynchronous operation experienced in Korea and rapidly detecting asynchronous state are descrived.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2014년도 추계학술대회 논문집
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• pp.175-176
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• 2014

본 논문은 HVDC C&P 시스템에 적용된 이중화 기술 및 기능을 설명한다. LS산전은 2009년 HVDC 사업을 착수한 이래 HVDC Control and Protection(C&P) System을 개발해 왔으며 현재 2010년부터 한국전력공사와 협동연구로 진행하고 있는 HVDC 제주 실증단지에 적용하여 실증운전 중이다. 당사가 개발한 HVDC C&P 시스템은 시스템의 신뢰성 및 가용성을 높이기 위해 Fully Redundancy 시스템으로 구성되고 Hot Standby 방식으로 제어 및 보호 알고리즘을 수행한다. 본 논문에서는 HVDC C&P 시스템의 구성과 제어기 및 네트워크의 이중화 구조에 대해 소개 하고자 한다.

• ETRI Journal
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• 제28권4호
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• pp.517-520
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• 2006

In this letter, a new sharing mechanism, SRLG sharing, is proposed, which allows the links of the same shared risk link group (SRLG) in a primary light tree to share protections in WDM optical networks. In previous studies, how to share spare resources with SRLG constraints has not been studied in multicast optical networks. In this letter, considering SRLG sharing, we propose a novel algorithm -multicast with SRLG sharing (MSS)- to establish a protection light tree. Finally, the algorithm MSS and the algorithm multicast with no SRLG sharing (MNSS) are compared through a simulation to show that our new sharing scheme of SRLG sharing is more efficient than that of no SRLG sharing in terms of spare resource utilization and blocking probability.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.265-267
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• 2002

This paper deals with an I/O simulator design for performance evaluation of reactor protection systems in nuclear power plants. The I/O simulator provides input signals for the reactor protection system, and acquires output signals from the initiation circuits. The simulator is based on VMEbus system, and all VMEbus boards are developed within the country.