• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.2090-2091
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• 2007

We investigated the characteristics of transformer type SFCL with neutral line. The transformer type SFCL having neutral line has achieved the simultaneous quench because the secondary winding has acted as parallel reactor. The fault current of SFCL was limited according to ratio of turn number between primary and secondary windings. Therefore, the power burden of superconducting element can be reduced by reduction of ratio of turn number between primary and secondary windings. As a result, we could expect reduction of it's volume in the transformer type SFCL.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.331-332
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• 2015

Since $20^{th}$ century, along with the rapid industrial advancement, the concentrated urban development in specific large cities have made people migrate to those cities, thus causing problems in the power system stability. In case of Korea, more than 40% of the power system demand comes from the consumers in Seoul Metropolitan area and the rate is expected to increase. With the continuous increase of power demand, in order to meet the demand for system reliability improvement, the power system was multi-looped for reliability enhancement, the problem of fault current happened. In this situation, there are several methods for fault current reduction likes current limiting reactor, replacing circuit breaker, splitting busses, etc. But these methods reached its limit, power system needs more fundamental solutions such as grid segmentation. In this paper, we assume grid segmentation already has been progressed using VSC BTB HVDC. Then, this paper discusses operating point of HVDC in metropolitan area considering loss minimization and handy flow control. The simulation is proceeded on 2027 KEPCO system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기설비전문위원
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• pp.63-65
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• 2006

A electrical fault is defined as any abnormal condition caused by a reduction in the insulation strength. To define the potential risk of the electric installation, measurement of leakage current has been getting considered, but because the measured leakage current value also contained leakage current by capacitance, the measured value could not be adapted to absolute reference to the installation. Therefore, in this paper, the correlation between the condition of electric installation and leakage current were analyzed. The result focuses on to detect them in a cost efficient way.

• 정보처리학회논문지A
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• 제8A권4호
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• pp.319-330
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• 2001

가상 메모리 시스템에서 프로세스가 현재 물리 메모리에 없는 페이지에 접근하게 되면 페이지 폴트가 발생하고, 이를 처리하기 위하여 예측할 수 없는 지연을 초래하는 페이지 폴트 핸들러가 동작하게 된다. 따라서 가상 메모리 시스템은 실시간 태스크의 제한 시간 실패율을 높여주는 요인이 될 수 있으므로 실시간 시스템에서 사용하기 어렵다. 뿐만 아니라, 새로운 태스크가 동적으로 유입되는 범용 운영체제 환경에서 가상 메모리 시스템은 태스크의 집중적인 페이지 폴트로 인하여 일시적인 과부하 상태에 빠질 수 있다. 본 논문에서는 집중적으로 발생하는 페이지 폴트에 의한 일시적인 과부하를 효율적으로 처리할 수 있는 RBPFH(Rate-Based Page Fault Handling) 알고리즘을 제시하고 있다 알고리즘의 특징은 현재 시스템의 자원을 모니터링하면서 페이지 폴트가 제한된 범위를 초과하지 않도록 분산시키는 방법을 사용하고 있으며, 페이지 폴트 처리 비율을 조정해줌으로써 동적으로 시스템의 부하가 변하는 상황을 고려하고 있다. RBPFH 알고리즘은 리눅스 운영체제에서 구현하였으며, 실험을 통하여 멀티미디어와 같은 연성 실시간 태스크를 지원하는데 있어서 유용하게 사용될 수 있음을 확인하였다. 실험 결과 RBPFH는 태스크의 제한 시간 실패율을 10%∼20% 감소시키고, 평균 지연 시간을 50%∼60% 감소시켜주었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.153-154
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• 2015

Voltage Source Converter HVDC (VSC-HVDC) are a better alternative than conventional thyristor based HVDC systems. Unfortunately, VSC-HVDC's full potential cannot be utilized up till now due to absence of suitable HVDC protection. Recently, hybrid HVDC circuit breakers (HDCCB) have been developed and successfully lab tested. However, their application and feasibility in VSC-HVDC needs to be investigated. In this research paper we have modelled an existing HDCCB and evaluated its impact on fault reduction and interruption in VSC-HVDC systems. The HDCCB was applied in Korean Jeju-Haenam VSC-HVDC system model and its impact was analyzed for HVDC line-to-ground and line-to-line faults. HDCCB successfully interrupted the fault current and prevented the damages to costly IGBTs and converter transformers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.500-502
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• 1995

Whenever faults(a fault) occur(s) in a particular section of a distribution system, some of loads get disconnected and are left unsupplied. Service should be restored to these affected load points as quickly as possible through network reconfiguration. An efficient technique is presented in this paper for this purpose. Network reduction and strategy testing the voltage and current constraints are the main contributions of this paper.

• 전기학회논문지P
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• 제55권4호
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• pp.196-201
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• 2006

A electrical fault that may generate an electrical disaster is defined as any abnormal condition caused by reduction in the insulation strength. To find out the abnormal condition, periodical inspections have being performed every 3 years. Recently, the number of empty houses during normal working hours is rising by dramatic increase in the number of nuclear families and double income families. To define the potential risk of the electric installation, measurement of zero phase current has been being considered. But the measured value could not be adapted to an absolute reference to the installation because the measured zero phase current value also contained capacitive leakage current. Therefore, in this paper, the correlation between the condition of the electrical installation and the zero phase current was analyzed. The result focuses on to detect them in a cost efficient way.

• 보건행정학회지
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• 제2권1호
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• pp.80-114
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• 1992

Current compensation schemes for medical malpractice based on negligence is absolutely malfunctioning in Korea. Focussing on the reform of present tort systems for resolving medical malpractice disputes, this paper discusses the alternative models of the Social Relief Schemes for Medical Malpractice (SRSMM). Alternative models of SRSMM should fundamentally be based on either negligence or nofalult compensation principle. On the foundation of the previous relief principle, the SRSMM should be equupped with three major components-the preventio/reduction of the sharp increasing medical malpractice, the effective and efficient resolving process for malpractice disputes and the proper social financing scheme for compensation. The paper deals with pros and cons of the possible alternative models for reform centering on the three major components of the scheme. As conclusions, administrative arbitration machinaries and a compulsory fund for compensating the injured under the negligence principle are proposed to resolve the current problems Korea has faced.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.367-370
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• 2000

It is shown that $I_{DDQ}$ testing is very useful for shipping fault-free CMOS ICs. However, test time of $I_{DDQ}$ testing is extremely larger than one of logic testing. In this paper, a new test input sequence generation methodology is proposed to reduce the test time of $I_{DDQ}$ testing. At first, it is Shown that $I_{DDQ}$ test time Will be denominated by charge supply current for load capacitance of gates whose output logic values are changed by test input vector application and the charge current depends on input sequence of test vectors. After that, a test input sequence generation methodology is proposed. The feasibility is checked by some experiments.riments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.503-505
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• 2003

본 논문에서는 방전갭을 이용한 시스 순환 전류 저감장치 보호유닛을 제안하여 SVL형식의 저감장치 보호유닛과 뇌써지시 과도특성을 비교하였으며, 또한 시스 순환전류 저감장치 보호유닛 적용시의 고장전류분류율을 검토한 결과 모든 경우에 대하여 각 접지선의 고장전류분류율이 현행의 기준을 만족함으로써 시스 순환전류 저감장치 보호유닛을 적용한 저감장치의 현장적용 가능성을 제시하였다.