• 대한의용생체공학회:의공학회지
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• 제17권4호
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• pp.491-498
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• 1996

The development of a compact two-wavelength Nd:YAG laser for dental and ENT applications is presented. The Nd:YAG resonator generates either 1.06$\mu$m or 1.32$\mu$m. The wavelength selection is made at the control panel. The Nd:YAG laser parameters at 1.06$\mu$m are ; the maximum pulse duration of 150$\mu$s, repetition rates of I-100Hz, and the maximum average power of 25W. At 1.32$\mu$m, the pulse duration is the same where the repetition rates and the maximum average power are I-30Hz and lOW respectively. High voltage power supply consists of a simmer module and two identical high voltage DC converters. In order to make a complete medical laser system, an optical fiber delivery unit, foot pedal and water spray handpiece are also developed. The wavelength selection is reliable since no movement of optical or mechanical components is required. The high voltage power supply is compact, easy to be maintained and applicable for other laser systems due to its modular design.

• Journal of Electrical Engineering and Technology
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• 제11권2호
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• pp.405-415
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• 2016

This paper presents a model predictive control for shunt active power filters in synchronous reference frame using space vector pulse-width modulation (SVPWM). The three phase load currents are transformed into synchronous rotating reference frame in order to reduce the order of the control system. The proposed current controller calculates reference current command for harmonic current components in synchronous frame. The fundamental load current components are transformed into dc components revealing only the harmonics. The predictive current controller will add robustness and fast compensation to generate commands to the SVPWM which minimizes switching frequency while maintaining fast harmonic compensation. By using the model predictive control, the optimal switching state to be applied to the next sampling time is selected. The filter current contains only the harmonic components, which are the reference compensating currents. In this method the supply current will be equal to the fundamental component of load current and a part of the current at fundamental frequency for losses of the inverter. Mathematical analysis and the feasibility of the suggested approach are verified through simulation results under steady state and transient conditions for non-linear load. The effectiveness of the proposed controller is confirmed through experimental validation.

• 전력전자학회논문지
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• 제22권1호
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• pp.36-43
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• 2017

This paper describes a hybrid multi-output three-level DC/DC converter suitable for a wide, high-input voltage range of an auxiliary power supply for a high-power photovoltaic generating system. In a high-power photovoltaic generating system, the solar panel output voltage depends on solar radiation quantity and varies from 450Vdc to 1100Vdc. The proposed hybrid multi-output three-level DC/DC converter, which is an auxiliary power supply, would be used as power source for control printed circuit boards and relay and cooling fans in a high-power photovoltaic generating system. The proposed multi-output ($24V_{DC}/30A$, $230V_{DC}/5A$) hybrid three-level boost converter, which uses an energy recovery snubber, is controlled by variable-frequency and phase-shifted modulations and can achieve zero-voltage switching with all operating conditions of input voltage and load range. Experimental results of a 2kW prototype are evaluated and implemented to verify the performance of the proposed converter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.2085-2087
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• 1997

The UPS for power plant is mainly used as the critical power supply of power plant. This is very much alike to the general UPS but it requires the special design criteria of power plant. In this study, we designed and develope system according to the design criteria of p plant. In the development of the special system, the designs of IGBT Drive, heat protection and monitoring system, and p components are key techniques. This Paper describes the power circuits, key techniques, the control and monitoring of the developed UPS(DC 125V $3{\Phi}$ 100K Finally, using the UPS we verified superiority through the type test.

• 농촌계획
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• 제27권3호
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• pp.93-102
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• 2021

This study was attempted to provide a scientific basis for the problem of location selection by spatial scale for efficient promotion of projects related to green care farm complex. Location potential assessment system in local government scale consists of two major components from demand-side and supply-side consideration. The demand-side aspect considered the characteristics of potential users, while supply-side aspect used total 18 indices over 8 divisions under 3 fields. For the location potential assessment in district scale, total 8 indices under 3 major divisions were considered based on biological, physical, social, and economic environment. The application results of the location potential evaluation system in local government scale(excluding metropolitan cities) showed high location potential in southern Gyeonggi Province and near Busan Metropolitan City. As a result of applying the district-scale location potential evaluation system to Geumsan-gun, Geumsan-eup, Chubu-myeon, and Jewon-myeon have high potential. Further studies to improve the applicability of the developed indices are recommended by enhancing assessment indices, complementing base data, and reinforcing with spatial analysis.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.53-56
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• 2008

A photovoltaic panel is a device that, through the photovoltaic effect, converts luminous energy into electric energy. Photovoltaic generation system used infinity of solar energy, cost of fuel is needless and there in no air pollution or waste occurrence. This paper summarizes the results of these efforts by offering a photovoltaic system structure in 30[kW] large scale applications installed in Mokpo National University dormitory roof. The status of photovoltaic system components, are inter-connection and safety equipment monitoring system will be summarized as this article. This describes configuration of utility interactive photovoltaic system which generated power supply for dormitory. In this paper represent 30[kW] utility photovoltaic system examination result.

• 한국추진공학회지
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• 제9권2호
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• pp.54-61
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• 2005

본 논문에서는 현재 개발 중인 스마트 무인기 연료 시스템의 기본설계 결과를 제시하고 이에 대한 신뢰도 분석을 수행하였다. 시스템 요구를 바탕으로 연료 시스템을 구성한 후, 이에 필요한 부스트펌프, 제트펌프, 도관, 벤트 시스템 등 각 구성품에 대한 설계를 수행하였고 참고 중량 데이터를 이용하여 연료 시스템의 중량예측을 수행하였다. 이를 바탕으로 연료 시스템의 신뢰도를 분석하여 신뢰도 목표를 만족함을 확인하였다.

• Smart Structures and Systems
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• 제24권1호
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• pp.37-52
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• 2019

Despite its success and wide application, base isolation system has been challenged for its passive nature, i.e., incapable of working with versatile external loadings. This is particularly exaggerated during near-source earthquakes and earthquakes with dominate low-frequency components. To address this issue, many efforts have been explored, including active base isolation system and hybrid base isolation system (with added controllable damping). Active base isolation system requires extra energy input which is not economical and the power supply may not be available during earthquakes. Although with tunable energy dissipation ability, hybrid base isolation systems are not able to alter its fundamental natural frequency to cope with varying external loadings. This paper reports an overview of new adventure with aim to develop adaptive base isolation system with controllable stiffness (thus adaptive natural frequency). With assistance of the feedback control system and the use of smart material technology, the proposed smart base isolation system is able to realize real-time decoupling of external loading and hence provides effective seismic protection against different types of earthquakes.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.233-236
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• 2005

본 논문에서는 현재 개발 중인 스마트 무인기 연료 시스템의 기본설계 결과를 제시하고 이에 대한 신뢰도 분석을 수행하였다. 시스템 요구를 바탕으로 연료 시스템을 구성한 후, 이에 필요한 부스트 펌프, 제트펌프, 도관, 벤트 시스템 등 각 구성품에 대한 설계를 수행하였고 연료 시스템의 중량 예측을 수행하였다. 이를 바탕으로 연료 시스템의 신뢰도를 분석하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1126-1127
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• 2008

A photovoltaic panel is a device that, through the photovoltaic effect, converts luminous energy into electric energy. Photovoltaic generation system used infinity of solar energy, cost of fuel is needless and there in no air pollution or waste occurrence. This paper summarizes the results of these efforts by offering a photovoltaic system structure in 30[kW] large scale applications installed in Mokpo National University dormitory roof. The status of photovoltaic system components, are inter-connection and safety equipment monitoring system will be summarized as this article. This describes configuration of utility interactive photovoltaic system which generated power supply for dormitory. In this paper represent 30[kW] utility photovoltaic system examination result.