Guozhi Xu

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Operational software systems often experience an “aging” phenomenon, characterized by progressive performance degradation and a sudden hang/crash failure. Software rejuvenation is a proactive fault-tolerance strategy aimed to prevent unexpected outages due to aging. Existing rejuvenation approaches can be largely classified into two types:(More)
A covariance matrix based anti-interference algorithm is proposed for SIMO OFDM systems. This algorithm constructs the interference-blocking filter without the information of the inferences. This algorithm is insensitive to the time synchronization error and to the carrier frequency synchronization error. Therefore, it is especially useful for the case when(More)
Software is playing a more and more important role in a system, and more and more studies show that system failures are more due to software faults than due to hardware faults. Therefore, software reliability has been one of the hottest research topics. Recently, a phenomenon, "software aging" is reported. In order to counteract this phenomenon, a proactive(More)
A covariance-based algorithm is proposed to find the interference blocking filter for single-input multiple-output orthogonal frequency division multiplexing (SIMO OFDM) systems. The algorithm uses only the auto-covariance matrix of the received signal. It does not require precise carrier synchronization and time synchronization, so it is applicable to an(More)
The status of the insulators in power line can directly affect the reliability of the power transmission systems. Computer vision aided approaches have been widely applied in electric power systems. Inspecting the status of insulators from aerial images has been challenging due to the complex background and rapid view changing under different illumination(More)
To improve the performance of RTS/CTS scheme in error-prone WLAN channel, this paper proposes an enhanced scheme utilizing Back-to-back DATA Retransmission and packet loss differentiation. With this new scheme, the packet which encounters transmission error can be retransmitted continuously without additional backoff time and RTS/CTS handshake. The system(More)