• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.875-879
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• 2006

Noise reduction has become a major issue of the duct air-conditioners. This paper describes the reduction of noise and vibration of rotational slim duct system. The design of slim duct system is the most important point of noise reduction in terms of the motor of 2f line noise, resonance noise between forced frequency and natural frequency of Sirocco fan, unbalance noise of motor axis and the noise induced refrigerant. The noise of duct system is mainly measured from diffuser and bottom of duct. The optimal design was implemented after measuring the effect of noise and vibration in each part which is composed of duct system. In this paper, experimental results show that the main elements in air-conditioner duct design. These elements are anti-vibration rubber of motor, axis length of motor, rubber coupler, materials of sirocco fan and control method of motor which are the most vital factors in reducing noise.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.12
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• pp.9-16
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• 2010

In this paper, we have proposed a new dimmable magnetic ballast for HID(High Intensity Discharge) lamps consisted of AC switches to variate inductance value by using Silicon Controlled Rectifiers and the isolated zero current detector on inductor. Conventional dimming ballast has used relays or Solid State Relays in AC switches. However, a relay is difficult to zero current switching, because it has long operating time(10[ms]), and price competitiveness of SSR is very low. The proposed AC switches are suitable to switch at zero inductor current and it is accurately detected by using a opto-coupler. SCR is cheaper than SSR, and it is suitable to switch at zero inductor current because SCR is automatically turned off under holding current at no gate signal. Operating principles, simulation results and experimental results of the proposed ballast are described.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.252-254
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• 2000

For many years, electric utility has used sustained interruption rates as a reliability index. Today, however, many electricity consumers are adversely affected by more subtle voltage disturbances such as harmonic distortion. This paper deals with observations of events that occur in the Dimmer circuits and phase control which could affect harmonics problem to the commercial power system. In order to reduce the effect of harmonics and design filters, Solid State Relay Dimmer(SCRs or TRIACs) and Noise Filter are described, and the effects of harmonics is also analyzed. IGBT Dimmer which is appropriate method to reduce harmonics and improve efficiency is introduced.

• Proceedings of the Korean Society of Computer Information Conference
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• 2012.07a
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• pp.303-304
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• 2012

본 눈문은 시각의 중요 수단으로 여겨지는 빛보다, 새로운 시각 표현 방법인 그림자에 초점을 맞추어 제작한 작품 에 대한 것으로 은 전통 시계인 해시계로부터 모티브를 얻었다. 이는 아두이노 보드(Arduino Board)와 SSR(Solid State Relay), 거리감지 센서, 220V 전구 등을 이용하여 제작했다. 이는 전구가 순차적으로 켜지면서 시계방향으로 그림자가 생기는 것을 작동 원리로 한다. 이 작품은 관객 참여를 바탕으로 하며 추후에 모바일 응용 분야로 발전될 가능성이 있다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.4
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• pp.1-5
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• 1998

This paper reports the developement of the protection circuit of electronic starter for fluorescent lamps of end-of-life. The key point of this paper is to protect for lamp of end-of-life by four operational amplifiers (OP AMP) and one solid state relay (SSR). In this paper we simulated the circuit by PSpice and compared with experimental results.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.6
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• pp.906-913
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• 2010

Recently, lots of researches are carried out to develop hybrid power generation system for ocean facility. Normally, the stand-alone type power system is used in the ocean facility, which is influenced by weather condition. To improve the efficiency, a various charging strategy with switching algorithm has been studied. In this paper, the power system using multi-level type is proposed. The simulation results based on actual data of photovoltaic and wave hybrid power system are presented. The results show that the rate of charging time is increased 5~11% and 7~47% respectively to compare the conventional technique.

• Journal of Korea Multimedia Society
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• v.19 no.8
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• pp.1471-1478
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• 2016

In this study, the system to manage the power automatically was implemented by using Arduino, Raspberry pi, and Beacon technologies. Before the research, pre-research was carried out with the analysis on the existing power management systems in the market in order to find a solution to reduce burdens from standby power and power waste with the increase of electric charges. The system is designed to be able to deliver and receive data through IEEE 802.15.4 wireless protocol, by using Xbee module. Arduino was tested to verify whether it is able to control SSR(Solid State Relay), and it was found that there is no problem. Meanwhile, it was also tested whether it is possible to organize a star topology network through Arduino and Raspberry Pi, and it was confirmed that normal wireless communication is possible through IEEE 802.15.4 wireless protocol. It is designed that the signal from Android smartphone application is to be delivered to Raspberry Pi and then, to be delivered to Arduino through Xbee so that Arduino could control SSR. In addition to this, wireless protocol required to control Arduino with Raspberry Pi is also designed and applied to this research.

• Journal of Internet of Things and Convergence
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• v.6 no.1
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• pp.97-102
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• 2020

Multi-Channel Switch ICs for IoT have integrated several solid state structure low ON-resistance bi-directional relay MOS switches with level shifter to drive high voltage and they should be independently controlled by external serialized logic control. These devices are designed for using in applications requiring high-voltage switching control by low-voltage control signals, such as medical ultra-sound imaging, ink-jet printer control, bare board open/short and leakage test system using Kelvin 4-terminal measurement method. This paper describes implementation of analog switch control block and its verification using Field programmable Gate Array (FPGA) test pattern generation. Each block has been implemented using Verilog hardware description language then simulated by Modelsim and prototyped in a FPGA board. Compare to conventional IC, The proposed architecture can be applied to fields where multiple entities need to be controlled simultaneously in the IoT environment and the proposed pattern generation method can be applied to test similar types of ICs.