• Journal of Power Electronics
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• v.16 no.6
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• pp.2057-2066
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• 2016

An extension of the one-cycle control (OCC) method for switched-capacitor (SC) converters is proposed in this paper, featuring a fast dynamic response, wide line and load operation ranges, and simplicity in implementation. To illustrate the operation principle of this nonlinear control method and to demonstrate its simplicity in design, a dual-phase unity gain SC converter is examined. A new control loop based on the charge balance in a flying capacitor is formulated for the OCC technique and implemented with a 15W dual-phase unity gain SC converter on a circuit board for control verification. The obtained experimental results show that external disturbances can be rejected in one switching cycle by the OCC controlled SC converter with good line and load regulations. When compared to other control methods, the proposed nonlinear control loop exhibits superior dynamic performance in suppressing input and load disturbances.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.746-749
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• 2004

In collaboration with SAMPYO KRT, VOSSLOH COGIFER has designed and supplied all turnouts for the first Korean high speed project.. The track is laid on ballast and the turnouts were designed accordingly and as per the SNCF standard for turnouts at commercial speed of 300 km/h and design speed of 350 km/h. KNR has now decided to implement a ballastless technology for the extension of the line between (South line). To the best of our knowledge, it has also been decided that the system to be used is ballastless Concrete bearer. Thus, the following presentation has been done with a technology for ballastless track with the same system.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.769-774
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• 2011

This study aimed at finding the factors impacting customer satisfaction (CS) for conversion farm with $2^{nd}$ and $3^{rd}$ industry, because the most important thing in the conversion farm is enhancing customer satisfaction. The data on CS from 173 pumpkin farm's customers by on-line survey were gathered. The analysis using structural equation model with Amos was carried out. Product, service and purchasing were determined as 3 factors impacting to CS. The result showed that purchasing is the biggiest contributor to CS. It means the customers using on-ine market are very sensitive to farm's brand and logistics. It is also found that conversion with processing and farm experience activity is definitely affecting to building customer's trust. In conclusion, making efforts on enhancing CS in conversion farm is the key to success.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.10a
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• pp.318-322
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• 2002

In this paper the automatic plate forming system developed by the present research group is introduced, which would be helpful for other researchers. The present system consists of three parts : heating line information generation software, automatic heating apparatus and numerical control system. The numerical control system developed by the present authors is detailed. Performance test for the developed system has been carried out and good results has been obtained. As an extension of the present study, the present automatic plate fanning system will be applied to surfaces found in ship and offshore structure.

• Journal of Digital Contents Society
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• v.7 no.4
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• pp.271-277
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• 2006

Recently, the mobile game market is growing due to the extension of mobile devices and internet. The mobile games are became a popular culture in society. But the existing mobile games have two simple forms. There are tow models in the mobile games. The first is as follows. The user downloads a game one time and play the game at off-line field. The second is as follows. The user play a battle game at on-line field. In the paper, we propose a new on-line "tug of war" game model which the user can play two kinds of game. They are the on-line battle mode game and the character raising mode game. Thus, this game model is different to existing mobile games and innovative model in mobile game market. This paper proposes a new research field in mobile game market with the characteristic that the user tan play two modes. One mode is the on-line tug of war battle mode and the other is the character raising mode.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.5
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• pp.129-136
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• 2011

This paper presents the coding method that have multi-mode and efficiency of audio codecs using the feature of audio signal. Recently, the developed extension super-wideband codec based on G.718 wideband divides two mode between Generic and Sinusiodal. So codec efficently encode audio signal exist in super-wideband. But the codec is not as efficent coding for harmonic component of wind instrument and string instrument and individual-Line component of percussion instrument. The proposed method are modeling and encoding multiple pitch and individual-line feature using multi mode coding. For the performance evaluation, we used SNR in MDCT domain for objective test and MUSHRA test for subjective test. As a result, the performance of SNR and MUSHRA test of the proposed method have better performance than the G.718 super-wideband codec.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.12
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• pp.2831-2838
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• 2014

This paper proposes the off-line handwritten flowchart symbol recognition algorithm by type and strength of a cross region of the straight line strokes that is extracted based the normalized dominant slope vectors. In the proposed algorithm, first of all, a connector symbol which consisted only curves is recognized by the special features, and the other symbols with straight line strokes are recognized by type and strength of a cross region, and that is extracted by extension of minimum bounding rectangle of the clusters of the normalized dominant slope vectors, and the straight line strokes of the symbols is extracted by the normalized dominant slope vectors. To confirm the validity of the proposed algorithm, the experiments are conducted for 10 different kinds of flowchart symbols that mainly used for computer program, and the number of symbols is 198. Experiment results were obtained the recognition rate of 99.5%, and the flowchart symbols is recognized correctly robust to variations, and then the proposed algorithm were found very effective for off-line handwritten flowchart symbol recognition.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.116-119
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• 2004

The existing monitoring and control systems of utility-pipe conduit (power tunnel, cable tunnel etc) have established communication lines using optical fiber, leaky coaxial cable (LCX), and several kinds of control cable. Due to the properties of the used media, the cost of equipment is considerably high and the maintenance of the system is difficult. Also, the term of carrying out is long so that the extension of the system is in difficulty. Now it is desirable to adopt Power Line Communication (hereinafter, PLC) technology in the monitoring and control systems and use the existing low-voltage power-line for lamplight as communication line. This will lead the reduction of the construction cost and the easy maintenance of the system. In this paper, we research the characteristics of PLC in conduit, design and manufacture the field test system, and analyze the performance of the system by field test. Then, we introduce the reliable monitoring and control system of utility-pipe conduit using PLC.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.6
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• pp.413-418
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• 2010

The amount of heat loss of a refrigerator through the gasket is nearly 30% of total refrigerator heat loss. In this paper, quantitative evaluation for the effects of various effort to reduce heat losses through the gasket. The first trial is to extend the inner gasket to prevent the heat loss flowing from the inner of refrigerator. The effects of thermal conductivity changes of gasket and magnet are investigated by the numerical heat transfer analysis. The position change of hot line is also examined in the present research. From the present result of the numerical simulation of heat transfer, we are able to reduce the heat loss about 20~40% by using inner gasket extension. The reducing of thermal conductivity of gasket is considerable in the heat loss reduction. On the other hand, the thermal conductivity change of magnet has no apparent effect in heat loss reduction. The position change of hot line has considerable positive effect in the reduction of heat loss near gasket region.

• Korean Journal of Agricultural Science
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• v.37 no.3
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• pp.351-354
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• 2010

This study was carried out to develop a new sweet sorghum for biomass by using mutagen, gamma-ray. Seeds treated were gained from National Genetic Resource Center, RDA, and these seeds were irradiated with gamma-ray (400Gy) at KAERI. CNUS-M113 and CNUS-M134 among 169 collected accessions were evaluated a promising line for biomass due to increasing of fresh and dry weight. In addition, this line was high in stem height, number of tiller and fresh weight per plant than check, Hwang-gum chal sorghum. Accordingly, this line demanded for leading variety the production test and cultivation adaptability in future years.