A novel packet switch architecture is proposed based on a channel grouped virtual circuit (CG-VC) scheme for high-speed communication networks. The case is considered in which there are several parallel channels betwe...
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A novel packet switch architecture is proposed based on a channel grouped virtual circuit (CG-VC) scheme for high-speed communication networks. The case is considered in which there are several parallel channels between two switching nodes. The CG-VC scheme allows a packet to select an available channel in such a way as to avoid congested channels using a simple, hardware-based, self-routing mechanism. As a result, the architecture provides efficient channel use and low switching delay. The performance of the proposed switch is evaluated by simulation. The results show the proposed switch significantly improves channel utilization and switching delay compared with conventional single-channel allocation transmission policies.< >
The variation of the intensity of environmental γ-rays has been studied with a Ge(Li) spectrometer. The 12 γ-rays were selected to be examined and typical characteristics of variations were obtained for each γ-ray....
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The variation of the intensity of environmental γ-rays has been studied with a Ge(Li) spectrometer. The 12 γ-rays were selected to be examined and typical characteristics of variations were obtained for each γ-ray. The intensity of γ-rays of 214Pb and 214Bi which are 222Rn daughter nuclei increases on rainy days to the severalfold value of the average in the case of no precipitation. These variations were observed to be roughly proportional to rainfall rate in a sequence of precipitation. The γ-ray intensity of nuclides of the thorium series and 137Cs is nearly constant within about 3% regardless of the weather. Its variation is about equal to the statistical fluctuation of the present measurements. The mean diurnal variations of γ-ray intensity were obtained on days without precipitation. The intensity of 214Pb and 214Bi γ-rays fluctuates nearly sinusoidally with an amplitude of about 6% of the average value and the maximum in the early morning.
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