• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.606-610
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• 2001

Voltage harmonics resulting from current harmonics produced by the nonlinear loads have become a serious problem in many systems. Moreover momentary interruptions and voltage sags are responsible for many of the power quality problems found in typical industrial plants. In this paper, proposed power system using series active power filter is not only harmonic compensation but also harmonic isolation between supply and load, and voltage regulation and unbalance compensation. The effectiveness of the proposed system is verified through computer simulations and experiments

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1341-1344
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• 2005

This study was aimed to verify the acceptable contact force between power collector and 3rd rail type conductor rail for the Korean standardized rubber-tired AGT light rail vehicle. The power collector was designed and manufactured to satisfy the Korean standardized Specifications of the rubber-tired AGT light rail vehicle. Based on the dynamic behavior, contact force variation and interruption in the worst installation tolerance of the conductor rail, its initial contact force was set up. At the test track for the Korean standardized rubber-tired AGT light rail vehicle, interruptions, stresses, vibrations, and contact force variations were measured. As the results, initial contact force was verified to ensure power collection stability.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.657-658
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• 2004

The reactor protection system (RPS) of HANARO is a safety class system. The reactor is tripped by dropping four shut off rods (SOR). The SOR system consists of a SOR, hydraulic pump, hydraulic cylinder, solenoid valves and a power supply unit which has the AC coil contactor as a switching component. The hydraulic pump lifts up the SOR. The SOR drops by loss of the hydraulic pressure in the hydraulic circuit at the occurrence of voltage sags or interruptions. From this experiment, we knew that the magnitude of the voltage sag which impacts on this system is 70V, 500msec. The reactor regulation system (RRS) of HANARO has four CARs which are connected to the driver through a magnetic clutch. The CAR drops by loss of electromagnetic force of the magnetic clutch when the deeper voltage sags to lower than 10V, 500msec.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.556-559
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• 2004

This study was aimed to verify the acceptable contact force between power collector and 3rd rail type conductor rail for the Korean standardized rubber-tired AGT light rail vehicle. The power collector was designed and manufactured to satisfy the Korean standardized Specifications of the rubber-tired AGT light rail vehicle. Based on the dynamic behavior, contact force variation and interruption in the worst installation tolerance of the conductor rail, its initial contact force was set up. With rotary disk type equivalent test apparatus with circular conductor rail, the interruptions were measured. As the results, acceptable contact force was proposed to ensure power collection stability.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.346-348
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• 2014

VTS 관제사의 가장 기본적인 업무는 모니터링과 동시다발적으로 발생하는 사건을 처리하는 업무라고 할 수 있다. 이러한 모니터링 업무와 동시발생 업무의 관리의 소홀 또는 실패가 VTS 관련 사고로 이어지는 경우가 많다, 그러함에도 불구하고 지금까지는 이 분야에 대한 연구가 부족하였다. 본고에서는 VTS 모니터링 업무와 동시발생 업무 관리의 특성을 분석하고 특히 방해와 산만을 일으키는 요소들을 집중적으로 검토하고 이것이 관제사의 역량에 미치는 영향을 알아보았다. 또한 이러한 문제의 해결책으로 미래계획기억과 분산 기억 시스템 이론을 적용하여 실질적으로 관제사 업무에 도움을 줄 수 있는 방법을 모색하였다. 또한 e-Navigation 과 관련하여 VTS 장비에 장착하여 관제사의 모니터링 업무와 동시다발 발생 업무 관리를 도울 수 있는 도구 개발에 대한 아이디어를 제안하였다.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.739-743
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• 2000

With significant development of power electronics technology the proliferation of nonlinear loads such as such as static power converters has deteriorated power quality in power transmission distribution systems. Notably voltage harmonics resulting from current harmonies produced by the nonlinear loads have become a serious problem in many systems Moreover momentary interruptions and voltage sags are responsible for many of the power quality problems found in typical industrial plants. Int his paper proposed 3 phase hybrid series active power filter is not only for harmonic compensation but also for harmonic isolation between supply and load and for voltage regulation and imbalance compensation Through computer simulations we have verified the effectiveness of the proposed system.

• Clinical and Experimental Pediatrics
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• v.60 no.1
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• pp.1-9
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• 2017

Malformations of cortical development are rare congenital anomalies of the cerebral cortex, wherein patients present with intractable epilepsy and various degrees of developmental delay. Cases show a spectrum of anomalous cortical formations with diverse anatomic and morphological abnormalities, a variety of genetic causes, and different clinical presentations. Brain magnetic resonance imaging has been of great help in determining the exact morphologies of cortical malformations. The hypothetical mechanisms of malformation include interruptions during the formation of cerebral cortex in the form of viral infection, genetic causes, and vascular events. Recent remarkable developments in genetic analysis methods have improved our understanding of these pathological mechanisms. The present review will discuss normal cortical development, the current proposed malformation classifications, and the diagnostic approach for malformations of cortical development.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.4
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• pp.176-181
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• 2001

Due to the increasing complexity to handle conflicts and interruptions caused by resource failures and rush orders, shop control is obliged to redesign its organization according to the changing demands of the manufacturing control. These demands are leading to the development of decentralization and gradually to their permanent optimization. As a result, a powerful modeling method which can be adapted efficiently is required. The use of agent theory enables specific modeling of the relevant shop planning activities. The planning activities are modeled in a so-called activity modeling through the definition of three classes of agents; Plan Agent, Manufacturing System Agent and Control Agent as well as the description of the cooperative relationship among these agents. On the basis of the activity model the agent-based shop control method is developed which emphasizes the distributed problem-solving and the cooperation with relevant agents.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1570-1575
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• 2018

The increased penetration of PV is impacting on grid operation and in particular the voltage within the local grid can be significantly influenced by the various PV systems. The increased penetration of PV is impacting on grid operation and in particular the voltage within the local grid can be significantly influenced by the various PV systems. This paper describes domestic technical standard of Photovoltaic(PV) PCS(Power Conditioning Systems)- Characteristics of the utility interface. Especially protective function test items of 1) Output overvoltage protection test, 2) Output undervoltage protection test, 3) Frequency rise protection test, 4) Frequency fall protection test, 5) System voltage's momentary interruptions, 6) System voltage distortion capability test. Therefore in this paper protective function test item of facilities evaluation detailed standards for new renewable energy, small, medium and large photovoltaic inverter standard is studied and analyzed and finally full tested by PV inverter performance function.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.347-349
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• 2005

This paper presents the results of an investigation and assessment of the direct short term impacts of electric service interruption incurred by livestock customers. The study used a direct visit survey to determine the customer assessment of electric service interruption and characteristic. The variation in interruption cost with the characteristics of interruptions such as duration, time of day, frequency, and day of interruption was also investigated.