• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.59-63
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• 2008

This paper analyze the operating characteristic of RCB due to the synthesize harmonic current. The RCB of rated sensitivity electric current with 30[mA] test to operating characteristic by synthesize harmonic current and it analyzed the tripping operation due to a harmonic current. The test result, the operating current of RCB changed by synthesize harmonic current.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.53-58
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• 2008

This paper analyze the operating characteristic of MCCB due to the synthesize harmonic current. Four types of MCCBs, divided by the type of operation system and a principle of operation, tested with 200[%] of rated current. The test result nuisance tripping did not occur but the time delay characteristic of the hydraulic magnetic type MCCB is appeared. From the place where the synthesize harmonic content is high it is good the hydraulic magnetic type MCCB not to use.

• The Journal of the Acoustical Society of Korea
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• v.27 no.1E
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• pp.11-16
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• 2008

In this paper, a pitch cycle waveform (PCW) is extracted, quantized, and interpolated in a time domain to synthesize high-quality speech at low bit rates. The pre-alignment technique is proposed for the accurate and efficient PCW extraction, which predicts the current PCW position from the previous PCW position assuming that pitch periods evolve slowly. Since the pitch periods are different frame by frame, the original PCW is converted into the fixed-dimension PCW using the dimension-conversion method, and subsequently quantized by code-excited linear predictive (CELP) coding. The excitation signal for the linear predictive coding (LPC) synthesis filter is generated using the time-domain interpolation and interlink of the quantized PCW's. The coder operates at 4.2 kbit/s and 3.2 kbit/s depending on the pitch period. Informal listening test demonstrates the effectiveness of the proposed coding scheme.