• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.148-150
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• 2003

A meaning of power quality has changed, which affects on an environmental change of existing electricity supply markets. Today, it should take both consumers and suppliers into consideration to develop information and communication technology and to increase the use of power and electronic equipments. As a result, it is necessary to develop a system to monitor power quality and to display data. In this paper, a system, as a power quality monitoring equipment, which can use protective replays with progress of microprocessor technology and provide information in the intranet/internet circumstances using web-based architecture is described.

• KIEE International Transactions on Power Engineering
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• 제12A권1호
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• pp.26-30
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• 2002

The four fuzzy criteria to distinguish the internal fault from the inrush fur the power transformer protection have been identified. They are based on the wave shape, terminal voltage, fundamental and second harmonic component of differential current. systematic way to determine the associated fuzzy membership function is also proposed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.381-383
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• 2004

This paper presents for service restoration Abstract -in electric power distribution systems. The aim of the service restoration is an emergency control in distribution system to restore out-of service areas as soon as possible when a fault occurs in distribution system. For this reason, this paper presents a new service restoration strategy for multi-outage areas. Proposed algorithm consists of two methods. One is individual restoration scheme, the other one is integrated restoration scheme. The former determines restoration order of outage areas based on restoration index. If the former method can not generate a feasible restoration plan, the latter would try to find new configuration without overloaded section through tie exchange method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.874-882
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• 2008

In a domestic, HSR-350x which has the maximum speed 350km/h was developed and then next, the next generation high speed train which has the maximum speed 400km/h has still been developing. With developing the next generation high speed railway, there need to be a general plan to make sure of dynamic safety though the a study on the crack and failure of rail by rolling contact fatigue. Therefore, this study investigated occurring stress of rail according to the track quality, train velocity, wheel radius, track stiffness, distance between sleepers, axial force using Eisenmann's equations. For the more, via the finite element method, it investigated shear force on the rail head which could be changed by the early crack length, angle and temperature. As a result, this study confirmed the main elements which effect on the fatigue life cycle of rail.

• International Journal of Stem Cells
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• 제17권2호
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• pp.158-181
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• 2024

This study offers a comprehensive overview of brain organoids for researchers. It combines expert opinions with technical summaries on organoid definitions, characteristics, culture methods, and quality control. This approach aims to enhance the utilization of brain organoids in research. Brain organoids, as three-dimensional human cell models mimicking the nervous system, hold immense promise for studying the human brain. They offer advantages over traditional methods, replicating anatomical structures, physiological features, and complex neuronal networks. Additionally, brain organoids can model nervous system development and interactions between cell types and the microenvironment. By providing a foundation for utilizing the most human-relevant tissue models, this work empowers researchers to overcome limitations of two-dimensional cultures and conduct advanced disease modeling research.

• 한국잠사곤충학회지
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• 제7권
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• pp.43-47
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• 1967

가잠 다교배와 차대잠의 형질을 연구하여 다음과 같은 결과를 얻었다. 1. 삼원이교배에 있어서는 이원이중교배와 같이 잠품종적인 수정선택성과 교배순서가 작용하여서 그 수정력이 차대잠 형질에 나타난다. 2. 사원삼교배에 있어서는 보통반문백색견, 용각백색견, 이호백색견 적색잠등을 공시하여 중복교배를 시켰던 바 차대에 모품종과 부품종 이외의 형질잠이나 형질잠은 전혀 나타나지 않았다. 3. 교미시간을 달리한 삼원이교배에서는 교미시간이 차대잠에 영향을 미치며 교미시간의 장단은 교배형식과 밀접한 관계가 있다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.217-219
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• 2005

배전계통의 소극적인 원격감시제어 만이 가능한 소규모 배전자동화 시스템이 1998년 처음 설치된 이후로 지금에 이르기까지 한국의 배전자동화 시스템은 종합 배전자동화로 이름만 변모 한 것이 아니라 기술수준과 표현능력에 있어서 비약적인 발전을 거듭하고 있다. 선로운영자의 계통상황 인식을 수월하게 하기위한 실지도상의 선로 표현창과 함께 기술검토를 위한 단선도 창이 추가되었고, 이를 통해 배전망 최적운영을 위한 다수의 기술검토용 운영프로그램들이 포함되어지고 있다. 본 논문에서는 고장발생시 그 위치를 추정하는 알고리즘을 연구하고 이를 배전자동화 시스템에 시험 적용한 사례를 소개한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.12-15
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• 2002

Korea Power System Protection Setting Rule was used from the rectify 1990's. Thereafter transmission voltage is raised the voltage into 765kV, and introduction to new technology of Power System, and was many of variation but, it is using. The present is using Digital type distance relay for 765kV transmission line protection. If impedance value of transmission line were to value lower than setting, this would be operating and relay setting rule is for 85% into Zone 1 self section, and Zone 2 is a 125%, Zone 3 is a 225%. Which's $15{\sim}25%$ include current transformer error 5%, potential transformer 5%, relay calculation error 5% and margin factor from the field experience. This paper is discussed transmission protective relay and relay setting rule of high voltage power system and we verify the correctness relay setting rule with distance relay using Matlab simulation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.487-490
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• 2002

Wind farm paralleled with electric power network can supply the power into a power network not only the normal conditions, but also the fault conditions of distribution network. If the fault happened in the power line with wind farm, the fault current level measured in a relaying point might be lower than that of distribution network without wind turbine generator. Consequently, it is difficult to detect the fault happened in the distribution network connected with wind generator. This paper describes the influence of wind turbine generator on the protective relaying system for detecting the fault occurred in a power line network. Simulation results shows that the fault current depends on the fault impedance, location, and the capacity of wind farm and distribution network load.

• 한국BIM학회 논문집
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• 제10권4호
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• pp.11-21
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• 2020

With increasing interest and research on smart cities, there is also an increasing number of studies on urban facilities that can be built within smart cities. According to these studies, smart cities' urban facilities are likely to become high value-added industries. However, the concept of smart city is not clear because it involves various fields. Therefore, in this study, the definition of Next-Generation(N.G) Smart City Facilities with Digital Twin and Digital Chain is carried out through a multidisciplinary approach. Based on this, Next-Generation Smart City Facilities will be divided into High Value-Added Products and Big Data Platforms. Subsequently, the definition of the Digital Chain containing the data flow of the entire process built through the construction of the Digital Twin proceeds. The definitions derived are applied to the Next-Generation Noise Barrier Tunnel to ensure that data is exchanged at the Digital Twin stage, and to review the proposed configuration of the Digital Chain and Data Flow in this study. The platform definition and Digital Chain of Next-Generation Smart City Facilities proposed in this study suggest that it can affect not only the aspects of data management that are currently in the spotlight, but also the manufacturing industry as a whole.