• 한국전자통신학회논문지
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• 제10권5호
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• pp.637-644
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• 2015

자전거는 자동차와 고속 이동하는 차량과 도로를 공유하며 운행 시 면허가 필요하지 않는 차량이다. 특히 일몰 후, 자전거에서 부적절한 차선 변경과 같은 경고가 없는 운행 변경으로 인해서, 사고를 발생할 수 있다. 이러한 사고 방지를 위해서 본 논문에서는 자동차에 적용되고 있는 안전 방향 표시 시스템을 자전거에 적용하고 이를 프로테우스 VSM 가상실험에 대한 적용으로 검증한다.

• Journal of Ecology and Environment
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• 제36권1호
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• pp.89-94
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• 2013

Diatoms have become an integral part of the UK's freshwater monitoring strategy over the past two decades, mostly in response to increasingly stringent European Union (EU) legislation. The use of diatoms is based on strong correlations between diatom assemblages and environmental variables, and from knowledge of the "expected" (= "reference") state of each river. The nationwide overview of the ecological health of rivers this gives allows those stretches of rivers which fail to meet EU criteria to be identified. This, in turn, allows appropriate remediation measures to be planned. Because diatom assemblages vary in space and time, even within a single water body, effective use of diatoms requires a consistent approach in order to minimise uncertainty. This includes the use of methods which comply with European Standards, a training and accreditation scheme for analysts, and a suite of quality assurance methods. Those aspects of uncertainty that cannot be readily controlled have been quantified and all estimates of ecological status are accompanied by the appropriate "confidence of class" and "risk of misclassification". This, in turn, helps planners prioritise those locations which are most likely to benefit from remediation.

• 전기학회논문지
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• 제56권3호
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• pp.524-530
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• 2007

This paper presents a new and simple method for sensorless operation of matrix converter drives using a constant air-gap flux and the imaginary power flowing to the motor. To improve low-speed sensorless performance, the non-linearities of a matrix converter drive such as commutation delays, turn-on and turn-off times of switching devices, and on-state switching device voltage drop are modelled using PQR transformation and compensated using a reference power control scheme. The proposed compensation method is applied for high performance induction motor drives using a 3 kW matrix converter system. Experimental results are shown to illustrate the feasibility of the proposed strategy.

• 전기학회논문지
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• 제65권10호
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• pp.1664-1671
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• 2016

This paper presents the analysis of the gate-source voltage of the gallium nitride high electronic mobility transistor (GaN HEMT) in the half bridge structure focused on the mutual effects of two switching operation. Especially low side gate-source voltage is analyzed mathematically according to the high side switch turn-on and turn-off operation. Moreover, the influence of each gate resistance and parasitic component on the switching characteristic of other side switch is investigated, and the formula, simulation and experimental results are compared with theoretical data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2142-2143
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• 2011

Amphibious possible, and good fuel economy, so as leisure and transport has increased the use of hovercraft. Fire started in Korea, the prevalence is increasing in demand as the trend has been increasing steadily. In this paper, the hovercraft's forward and backward direction can be controlled in order to free the reverse bucket control system was developed. Control due to development by promoting the flow of air and turn right, turn left and easy to reverse the life-saving and stable at high speed, etc. has made possible the operation of hovercraft. To prove the validity of the proposed controller in Matlab simulation and the actual delivery at the firehouse, built into a model for the demonstration test was performed.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.388-391
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• 2000

In this paper a modified ZVZCS(zero-voltage/zero-current switching) commutation cell with minimum additional components which provides soft switching at both turn-on and turn-off of main and auxiliary switches as well as diodes in PWM converters is presented. The proposed soft-switching technique is suitable for not only minority but also majority carrier semiconductor devices. The auxiliary switch of the proposed ZVZCS commutation cell is in parallel with the main switch and therefore there is no current stress on the main switch and diode. The operation principles of the proposed ZVZCS commutation cell are theoretically analyzed using the PWM boost converter topology as an example. Theoretical analysis simulation and experimental results verify the validity of the PWM boost converter topology with the proposed ZVZCS commutatioin cell.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 추계학술대회 논문집
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• pp.184-186
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• 2007

본 논문에서는 소프트 스위칭 다상 부스트 컨버터 회로를 제안하였다. 태양의 일사량 및 주위온도 등에 의해 출력전압의 변동이 많은 태양전지로부터 정전압을 얻기 위해서 고효율의 전력변환 장치가 필요하다. 제안된 컨버터를 이용하여 동작 범위 내에서 변동하는 입력전압을 정출력전압으로 제어하고, 입력전류 리플과 출력전압 리플을 저감시킬 수 있다. 또한 ZVS, ZCS를 이용하여 스위칭 순간에 Turn-on, Turn-off 손실을 감소할 수 있다. 본 논문에서는 소프트 스위칭 다상 부스트 컨버터를 적용하여 시뮬레이션을 수행하였다.

• Journal of Power Electronics
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• 제16권4호
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• pp.1298-1305
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• 2016

This paper presents the development of a short-circuit protection mechanism on a high voltage switch (HVS) board which is built by a series connection of semiconductor switches. The HVS board is able to quickly detect and limit the peak fault current before the signal board triggers off a gate signal. Voltage clamping techniques are used to safely turn off the short-circuit current and to prevent overvoltage of the series-connected switches. The selection method of the main devices and the development of the HVS board are described in detail. Experimental results have demonstrated that the HVS board is capable of withstanding a short-circuit current at a rated voltage of 10kV without a di/dt slowing down inductor. The corresponding short-circuit current is restricted to 125 A within 100 ns and can safely turn off within 120 ns.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.338-339
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• 2011

본 논문에서는 SRC를 이용한 고효율 차량탑재형 충전기를 제안한다. 제안한 컨버터는 앞단의 부스트컨버터가 역률보상과 동시에 배터리의 전압 전류 제어를 수행하고 후단의 SRC를 고정듀티와 고정주파수로 동작시켜 전 부하영역에서 스위치와 다이오드의 ZCS 턴온 턴오프가 가능하다. 3.3kW의 시작품으로 부터 CC-CV 충전을 통한 제안한 방식의 타당성을 검증한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.147-148
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• 2011

In this paper, implementation of digital control for critical conduction mode power factor correction (PFC) rectifier is presented. Critical conduction mode is widely used in medium and low power conversion application due to its minimized MOSFET turn-on loss and diode reverse-recovery problem. However, it needs additional zero current detection circuit and maximum frequency limit to properly turn the MOSFET on and avoid the excessive switching loss in light load operation. This paper explains the digital IC implementation and verifies its operation with 200-W prototype PFC rectifier.