• Computers and Concrete
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• 제29권4호
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• pp.209-217
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• 2022

In order to analyze the static and dynamic structural characteristics of the Obermeyer gate under overflow conditions, the force characteristics and vibration characteristics of the shield plate structure are studied based on the fluid-solid coupling theory. In this paper, the effects of the flow rate, airbag pressure and overflow water level on the structural performance of shield plate of air shield dam are explored through the method of controlling variables. The results show that the maximum equivalent stress and total deformation of the shield plate decrease first and then increase with the flow velocity. In addition, they are positively correlated with the airbag pressure. What's more, we find that the maximum equivalent stress of the shield plate decreases first and then increases with the overflow water level, and the total deformation of the shield plate decreases with the overflow water level. What's more importantly, the natural frequency of the shield structure of the Obermeyer gate is concentrated at 50 Hz and 100 Hz, so there is still the possibility of resonance. Once the resonance occurs, the free edge of the shield vibrates back and forth. This work may provide a theoretical reference for the safe and stable operation of the shield of the Obermeyer gate.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2006년도 학술발표회 논문집
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• pp.1964-1969
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• 2006

In order to solve the problem of the existing gate it developed the solar energy gate. The solar energy gate quotient a friction force from the area contact which will call improved with line contact and it diminished. Because of the result, The operation power of the gate came to be small and the small-sized of the motor was possible. From the small-sized of the motor, the solar energy system introduction was possible and the expense for the production establishment of the gate was diminished. From KRC in 2005 demonstration it establishes the solar energy gate in nationwide 50 places and characteristic the monitoring efficiently.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.157-158
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• 2000

In this study, to get the larger drain current of the device under the same operation condition as the conventional gate dielectric SiNx thin film transistor devices, we introduced new gate dielectric $Ta_2O_5$ thin film which has high dielectric constant $({\sim}25)$ and good electrical reliabilities. For the application for the TFT device, we fabricated the $Ta_2O_5$ gate dielectric TFT on the low-temperature-transformed polycrystalline silicon thin film using the self-aligned implantation processing technology for source/drain and gate doping. The $Ta_2O_5$ gate dielectric TFT showed better electrical performance than SiNx gate dielectric TFT because of the higher dielectric constant.

• 조명전기설비학회논문지
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• 제17권6호
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• pp.83-88
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• 2003

본 논문에서는 IPM의 전기적인 기생 성분 중에서 성능에 가장 크게 영향을 미치는 밀러 커패시턴스에 의하여 발생하는 오동작을 시뮬레이션을 통하여 증명하고 이를 최소화하기 위한 방법을 제시한다. 게이트와 컬렉트 단자간에 형성되는 밀러 커패시턴스와 밀접하게 관련된 게이트-에미터 사이의 기생 커패시턴스와 게이트 저항과의 상관 관계를 PSpice 시뮬레이션을 통하여 분석한다. 또한 시뮬레이션 결과를 바탕으로 IPM의 오동작을 최소화하기 위한 보조 회로를 삽입한 주문형 IPM을 제시한다. 표준형 IPM과 오동작 방지를 위해 보조회로가 삽입된 주문형 IPM의 실험 파형을 통해서 주문형 IPM이 약 3 [V]의 오동작에 대한 여유 전압을 가짐을 확인할 수 있다.

• 대한전기학회논문지
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• 제43권2호
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• pp.251-258
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• 1994

To apply the Power MOSFET to the high powerd circuits, the parallel operation of the Power MOSFET must be considered because of their low power rating. This means, in practical applications, design methods for the parallel operations are required. However, it is very difficult to investigate the problem of parallel operations by directly changing the internal parameters of the MOSFET. Thus, in this paper, the effects of internal parameters for the parallel operation are investigated using SPICE program which is often used and known that the program is very reliable. The investigation results show that while the gate resistance and gate capacitances are the parameters which affect to the dynamic switching operations, the drain and source resistances are the parameters which affect to the steady-state current unbalances. Through this investigation, the design methods for the parallel operation of the MOSFET are suggested, which, in turn, contributes to the practical use of Power MOSFETs.

• 전력전자학회논문지
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• 제3권4호
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• pp.426-436
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• 1998

Identification of fault current during the operation of a power semiconductor switch and activation of suitable remedial actions are important for reliable operation of power converters. A short circuit is a basic and severe fault situation in a circuit structure such as voltage source converters. This paper presents a new active protection circuit for fast and precise clamping and safe shutdown of fault currents of the IGBTs. This circuit allows operation of the IGBTs with a higher on-state gate voltage, which can thereby reduce the conduction loss in the device without compromising the short circuit protection characteristics. The operation of the circuit is studied under various conditions, considering variation of temperature, rising rate of fault current, gate voltage value, and protection circuit parameters. An evaluation of the operation of the circuit is made using IGBTs from different to confirm the effectiveness of the protection circuit.

• 센서학회지
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• 제30권5호
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• pp.295-299
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• 2021

In this study, we present a complementary metal-oxide-semiconductor (CMOS) binary image sensor. It can shoot an object rotating at a high-speed by using a gate/body-tied (GBT) p-channel metal-oxide-semiconductor field-effect transistor (PMOSFET)-type photodetector. The GBT PMOSFET-type photodetector amplifies the photocurrent generated by light. Therefore, it is more sensitive than a standard N+/P-substrate photodetector. A binary operation is installed in a GBT PMOSFET-type photodetector with high-sensitivity characteristics, and the high-speed operation is verified by the output image. The binary operations circuit comprise a comparator and memory of 1- bit. Thus, the binary CMOS image sensor does not require an additional analog-to-digital converter. The binary CMOS image sensor is manufactured using a standard CMOS process, and its high- speed operation is verified experimentally.

• 정보처리학회논문지A
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• 제10A권5호
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• pp.513-518
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• 2003

세계항만의 컨테이너 물동량은 2011년까지 연평균 8.8%로 꾸준히 증가할 것으로 예상하고 잇으며, 기존 항만 시설로는 이러한 추세를 충족시키 수 없기 때문에 시설 확충은 필연적이다. 그리고 항만에서 발생되는 비용이 전체 물동량에 발생되는 비용의 30%를 차지하고 있기 때문에 세계 주요항만에서는 점차 높아지는 인건비와 부족한 노동력 문제를 해결하고 토지 이용과 작업 능률을 극대화하기 위한 항만 시설의 자동화에 노력을 기울이고 있다. 특히, 항만시설 중에서도 화물이 발생되고 소멸되는 장소로서 정보의 시작점과 종착점이 되는 게이트의 자동화가 무엇보다도 중요한 이슈로 대두되고 있다. 본 연구에서는 항마의 게이트를 최적으로 자동화하는데 적합한 설계 방안을 제시하고자 한다. 먼저 게이트의 적정 규모를 산정하고, 1단계 게이트와 2단계 게이트 운영방식을 비교하며, 최적의 게이트 자동화 운영 방식을 설계한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 추계학술대회
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• pp.3-4
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• 2011

This paper presents a survey of floating power supply based on bootstrap operation for three-level voltage-source inverters. The floating power supply for upper switches is achieved by the bootstrap capacitor charged during on-time of the switch underneath. Hence, a large number of bulky isolated DC/DC power supplies for each gate driver are reduced. The Pspice simulation results show the behavior of bootstrap devices and the performance of bootstrap capacitor voltage.

• 한국농공학회지
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• 제34권2호
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• pp.40-48
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• 1992

A model using a linear programming technique was developed to operate gates for the optimum management of small of medium size agricultural reservoirs. To predict the inflow into the reservoirs the WASHMO model, which was a single event hydrology model, was modified and used. To test the applicability, the developed model was applied to two reservoirs located in Kyungpook province. The results showed that the model could be used for the optimum gate operation of the agricultural reservoirs.