Competition of spatial and temporal instabilities under time delay near the codimension-two Turing-Hopfbifurcations is studied in a reaction-diffusion equation.The time delay changes remarkably the oscillation frequen...Competition of spatial and temporal instabilities under time delay near the codimension-two Turing-Hopfbifurcations is studied in a reaction-diffusion equation.The time delay changes remarkably the oscillation frequency,theintrinsic wave vector,and the intensities of both Turing and Hopf modes.The application of appropriate time delaycan control the competition between the Turing and Hopf modes.Analysis shows that individual or both feedbacks canrealize the control of the transformation between the Turing and Hopf patterns.Two-dimensional numerical simulationsvalidate the analytical results.展开更多
Underground mining is a hazardous industrial activity. In order to provide a safe working environment for miners, a Wireless Sensor Network (WSN) technology has been used for security monitoring. It can provide a wide...Underground mining is a hazardous industrial activity. In order to provide a safe working environment for miners, a Wireless Sensor Network (WSN) technology has been used for security monitoring. It can provide a wide range of surveillance with a relatively low cost. In this study, an Energy-Based Multipath Routing (EBMR) protocol is proposed, which considers residual energy capacity and link quality in choosing hops and routing paths. Hops and paths with a high residual energy capacity and link quality will have the best chance to be selected to transmit data packages. Since the EBMR stores several routes in the routing table, when the current path fails, another path will be chosen to fulfill the task immediately. In this way, EBMR improves reliability and decrease time latency. Compared to AOMDV and REAR, EBMR decreases time latency by 51% and 12%.展开更多
基金Supported by the Fundamental Research Funds for the Central Universities under Grant No. 09ML56the Foundation for Young Teachers of the North China Electric Power University, China under Grant No. 200611029
文摘Competition of spatial and temporal instabilities under time delay near the codimension-two Turing-Hopfbifurcations is studied in a reaction-diffusion equation.The time delay changes remarkably the oscillation frequency,theintrinsic wave vector,and the intensities of both Turing and Hopf modes.The application of appropriate time delaycan control the competition between the Turing and Hopf modes.Analysis shows that individual or both feedbacks canrealize the control of the transformation between the Turing and Hopf patterns.Two-dimensional numerical simulationsvalidate the analytical results.
基金Financial support for this study, provided by the National Natural Science Foundation of China (No.60674002) the Science and Technology Research of the Ministry of Railways of China (No. 2006x006-E), is gratefully acknowledged
文摘Underground mining is a hazardous industrial activity. In order to provide a safe working environment for miners, a Wireless Sensor Network (WSN) technology has been used for security monitoring. It can provide a wide range of surveillance with a relatively low cost. In this study, an Energy-Based Multipath Routing (EBMR) protocol is proposed, which considers residual energy capacity and link quality in choosing hops and routing paths. Hops and paths with a high residual energy capacity and link quality will have the best chance to be selected to transmit data packages. Since the EBMR stores several routes in the routing table, when the current path fails, another path will be chosen to fulfill the task immediately. In this way, EBMR improves reliability and decrease time latency. Compared to AOMDV and REAR, EBMR decreases time latency by 51% and 12%.
