• Journal of KIISE:Computer Systems and Theory
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• v.34 no.2
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• pp.57-64
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• 2007

This paper proposed the low power texture cache for mobile 3D graphics accelerators. It is very important to reduce the leakage power in the standby mode for mobile 3D graphics accelerators and the memory access latency of texture mapping in the active mode which needs a large memory bandwidth. The proposed structure reduces the leakage power using variable threshold values of power mode transitions according to the selected texture filtering algorithms of application programs, which has the run time gain for texture mapping. In the trace driven cache simulation the proposed structure shows the best 7% performance gain to the previous MSA cache according to the new performance metric considering both normalized leakage power and run time impact.

• The Journal of the Korea Contents Association
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• v.6 no.12
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• pp.89-95
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• 2006

The performance of blind source separation(BSS) using independent component analysis (ICA) declines significantly in a reverberant environment. A post-processing method proposed in this paper was designed to remove the residual component precisely. The proposed method used modified NLMS(normalized least mean square) filter in frequency domain, to estimate cross-talk path that causes residual cross-talk components. Residual cross-talk components in one channel is correspond to direct components in another channel. Therefore, we can estimate cross-talk path using another channel input signals from adaptive filter. Step size is normalized by input signal power in conventional NLMS filter, but it is normalized by sum of input signal power and error signal power in modified NLMS filter. By using this method, we can prevent misadjustment of filter weights. The estimated residual cross-talk components are subtracted by non-stationary spectral subtraction. The computer simulation results using speech signals show that the proposed method improves the noise reduction ratio(NRR) by approximately 3dB on conventional FDICA.