Airborne networks（ANs） are special types of ad hoc networks that can be used to enhance situational awareness, flight coordination and flight efficiency in civil and military aviation.Compared to ground networks, AN...Airborne networks（ANs） are special types of ad hoc networks that can be used to enhance situational awareness, flight coordination and flight efficiency in civil and military aviation.Compared to ground networks, ANs have some unique attributes including high node mobility, frequent topology changes, mechanical and aerodynamic constrains, strict safety requirements and harsh communication environment.Thus, the performance of conventional transmission control protocol（TCP） will be dramatically degraded in ANs.Aircraft commonly have two or more heterogeneous network interfaces which offer an opportunity to form multiple communication paths between any two nodes in ANs.To satisfy the communication requirements in ANs, we propose aeronautical multipath transport protocol（Aero MTP） for ANs, which effectively utilizes the available bandwidth and diversity provided by heterogeneous wireless paths.Aero MTP uses fountain codes as forward error correction（FEC） codes to recover from data loss and deploys a TCP-friendly rate-based congestion control mechanism for each path.Moreover, we design a packet allocation algorithm based on optimization to minimize the delivery time of blocks.The performance of Aero MTP is evaluated through OMNe T＋＋ simulations under a variety of test scenarios.Simulations demonstrate that Aero MTP is of great potential to be applied to ANs.展开更多
We discuss the problem of identification of the dynamical generators for open two-level quantum systems in a Markovian environment.Based on Bloch sphere representation,the identification problem is converted to the es...We discuss the problem of identification of the dynamical generators for open two-level quantum systems in a Markovian environment.Based on Bloch sphere representation,the identification problem is converted to the estimation of a 3-dimensional real process matrix A and an inhomogeneous term c.The parameter identifiability and sufficient conditions for completely identification of A and c are obtained.Further discussion shows that the obtained sufficient conditions are not always necessary.The approach can be generalized to finite-level open quantum systems in an arbitary Markovian environment.展开更多
文摘Airborne networks（ANs） are special types of ad hoc networks that can be used to enhance situational awareness, flight coordination and flight efficiency in civil and military aviation.Compared to ground networks, ANs have some unique attributes including high node mobility, frequent topology changes, mechanical and aerodynamic constrains, strict safety requirements and harsh communication environment.Thus, the performance of conventional transmission control protocol（TCP） will be dramatically degraded in ANs.Aircraft commonly have two or more heterogeneous network interfaces which offer an opportunity to form multiple communication paths between any two nodes in ANs.To satisfy the communication requirements in ANs, we propose aeronautical multipath transport protocol（Aero MTP） for ANs, which effectively utilizes the available bandwidth and diversity provided by heterogeneous wireless paths.Aero MTP uses fountain codes as forward error correction（FEC） codes to recover from data loss and deploys a TCP-friendly rate-based congestion control mechanism for each path.Moreover, we design a packet allocation algorithm based on optimization to minimize the delivery time of blocks.The performance of Aero MTP is evaluated through OMNe T＋＋ simulations under a variety of test scenarios.Simulations demonstrate that Aero MTP is of great potential to be applied to ANs.
基金supported by the National Natural Science Foundation of China(60974037,61134008)SGS acknowledges funding from EPSRC ARF Grant EP/D07192X/1 and Hitachi
文摘We discuss the problem of identification of the dynamical generators for open two-level quantum systems in a Markovian environment.Based on Bloch sphere representation,the identification problem is converted to the estimation of a 3-dimensional real process matrix A and an inhomogeneous term c.The parameter identifiability and sufficient conditions for completely identification of A and c are obtained.Further discussion shows that the obtained sufficient conditions are not always necessary.The approach can be generalized to finite-level open quantum systems in an arbitary Markovian environment.
