• Smart Structures and Systems
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• 제4권2호
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• pp.261-278
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• 2008

The results of the application of shape memory alloy (SMA) prestressing devices on an aqueduct are presented in this paper. The aqueduct was built in 1747 to provide water to the city of Larnaca and to its port. Because of its importance to the cultural heritage of Cyprus, the aqueduct has been selected as one of the case-study monuments in the project Wide-Range Non-Intrusive devices toward Conservation of Historical Monuments in the Mediterranean Area (WIND-CHIME). The Department of Antiquities of Cyprus, acting in a pioneering way, have given their permission to apply the devices in order to investigate their effectiveness in providing protection to the monument against probable catastrophic effects of earthquake excitation. The dynamic characteristics of the structure were determined in two separate occasions and computational models were developed that matched very closely the dynamic characteristics of the structure. In this paper the experimental setup and the measured changes in the dynamic characteristics of the monument after the application of the SMA devices are described.

• 조명전기설비학회논문지
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• 제27권2호
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• pp.29-35
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• 2013

For the purpose of designing and applying optimum surge protection, one of the essential points is to take into account the energy coordination between cascaded surge protective devices(SPDs) and it is important to obtain an acceptable sharing of the energy stress between two cascaded SPDs. In this paper, in case of two voltage-limiting SPDs connected in parallel, the amount of splitting impulse current and energy that flow through each SPDs is investigated as a function of the protective distance. As a result, the energetic coordination between cascaded SPDs is strongly dependent on the voltage protection level of SPDs and the protective distance. It was confirmed that the sharing of the energy between two cascaded SPDs and the limited voltage levels are appropriate when the voltage protection levels of both upstream and downstream SPDs are the same.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.625-626
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• 2007

This study is on the protection system of Korean power system applying superconducting power devices. We investigates firstly protection systems of Korean power system and then do a basic study on the impact of relay systems in the power system with superconducting devices. For the more reliable result, we will carry out relay operation tests in the power system applying superconducting facilities using RTDS(Real Time Digital Simulator) in the future.

• 한국컴퓨터정보학회논문지
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• 제27권7호
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• pp.57-64
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• 2022

본 논문에서는 최근 대두되고 있는 디지털 헬스케어의 정의와 개요, 핵심기술, 그리고 디지털 헬스케어 기기 및 데이터를 사이버공격으로부터 보호할 수 있는 디지털 헬스케어 차세대 정보보안모델 수립 방안을 제안하고자 한다. 디지털 헬스케어기기와 데이터를 대상으로 다양한 취약점이 존재하고 있으며, 그 취약점에 대하여 사이버공격이 가능하다. 디지털 헬스케어 기기 및 정보통신망에 대한 공격을 통하여 직접적으로 사람의 생명 및 건강에 악영향을 끼칠 수 있으며, 디지털 헬스케어 데이터는 의료, 민감정보와 개인정보를 포함하고 있으므로, 필수적으로 사이버공격으로부터 안전하게 보호를 해야 한다. 본 제안의 경우 디지털헬스기기에 대한 장비 및 통신망에 대한 사이버공격과 데이터에 대한 지속적인 안전한 관리를 위해서는 차세대 정보보호체계 수립을 통하여 보다 효과적이며, 지속적으로 대응할 수 있을 것으로 전망된다.

• 스마트미디어저널
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• 제10권2호
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• pp.84-91
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• 2021

EU의 GDPR에 따르면 개인정보를 수집할 때 정보 주체(사용자)의 동의 혹은 거절하는 권리가 가장 우선시 되고 있다. 그러므로 정보 주체는 언제라도 동의 철회 및 잊힐 권리를 주장할 수 있어야 한다. 특히, 제한적인 IoT 장치(Constrained Node)에서는 프라이버시에 민감한 데이터의 수집, 처리 등에 대해 정보 주체의 동의 기능 구현 및 수집 정보의 활용 내용을 게시하기 매우 어렵다. 본 논문에서는 정보 주체가 IoT 장치에서 수집, 처리되는 데이터를 모니터링하여, 정보 유출의 문제를 인지하고, 연결 및 장치 제어가 가능한 관리 시스템을 설계하고 구현하였다. IoT 장치의 표준 OCF(Open Connectivity Foundation)와 장치 연결 프레임워크인 AllJoyn의 공통 정보를 고려하고, 정보 보호를 위한 메타 데이터 10개를 정의하였다. 이를 DPD(Data Protection Descriptor)라고 명명하였으며, DPD를 기반으로 정보 주체가 정보를 관리할 수 있는 SW인 DPM(Data Protection Manager)를 개발하였다.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권3호
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• pp.91-98
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• 2003

The importance of improving the quality of electric power is being strongly raised, owing to an increasing use of sensitive and small-sized electronic devices and systems. The transient over-voltages on low-voltage power distribution systems are induced by direct or indirect lightning return strokes. These can cause damage and/or malfunction of the utility systems for home automation, office automation, factory automation, medical automation, etc. The behaviors of lightning overvoltages transferred through the transformer to the low-voltage distribution systems using a Marx generator were experimentally investigated. Furthermore, the coupling mechanisms of lightning overvoltages transferred to the low-voltage systems were clearly illustrated through a theoretical simulation using a Pspice program. The overvoltages in low-voltage ac power systems are rarely limited by the application of the surge arrester to the primary side of the distribution transformer. A superior surge protection scheme is to install surge protection devices at the service entrance switchboard and/or at the load devices in TN power systems.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 추계학술대회 논문집
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• pp.85-86
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• 2013

This paper describes the physical configuration and features of the advanced control and protection devices, and operation control and monitoring system that are connected to a real time simulator for LS Industrial System 80kV 60 MW Jeju HVDC Pilot Project. Highlight of simulation result are provided to demonstrate the control and protection functionality.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1727-1731
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• 2003

In this paper we proposed backward fuzzy Petri-net to diagnoses faults in power systems by using the time sequence information of protection system. As the complexity of power systems increases, especially in the case of multiple faults or incorrect operation of protective devices, fault diagnosis requires new and systematic methods to the reasoning process, which improves both its accuracy and its efficiency. The fuzzy Petri-net models of protection system are composed of the operating process of protective devices and the fault diagnosis process. Fault diagnosis model, which makes use of the nature of fuzzy Petri-net, is developed to overcome the drawbacks of methods that depend on operator knowledge. The proposed method can reduce processing time and increase accuracy when compared with the traditional methods. And also this method covers online processing of real-time data from SCADA (Supervisory Control and Data Acquisition)

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 춘계학술대회논문집
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• pp.298-302
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• 2005

This paper presents the protection effect of SPDs according to installation conditions. To develop the effective protection countermeasures of information and communication equipments against lightning surges, actual-sized experiments in relation to the protection effects on the installation positions of surge protective devices(SPDs), the length of branch circuit the materials and long of conduit were conducted. The best method for protecting the electronic equipments from surges is to install the SPD at the front point of the devices to be protected. The installation method of the metal conduit bonded with common ground conductor were more effective than that of the PVC conduit.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.629-631
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• 2005

The DASPRO (Protection Coordination Program for DAS) is one of the application programs for Distribution Automation System (DAS) of the KEPCO. Application programs developed by KEPCO provide optimal operation in distribution network. The DASPRO includes diverse functions to operate network as construction of database using existing information. creation of diagram for protection coordination. calculation of fault current. evaluation network. power quality monitoring, etc. The DASPRO can examine validity of setting values for protective devices by comparing to T-C curves. Unless the protection coordination is correct, the most suitable setting value for protection devices are displayed on the screen. In this paper, I will introduce the contents of the DASPRO.