In this paper we propose a new discrete bidirectional associative memory (DBAM) which is derived from our previous continuous linear bidirectional associative memory (LBAM). The DBAM performs bidirectionally the opti...In this paper we propose a new discrete bidirectional associative memory (DBAM) which is derived from our previous continuous linear bidirectional associative memory (LBAM). The DBAM performs bidirectionally the optimal associative mapping proposed by Kohonen. Like LBAM and NBAM proposed by one of the present authors,the present BAM ensures the guaranteed recall of all stored patterns,and possesses far higher capacity compared with other existing BAMs,and like NBAM, has the strong ability to suppress the noise occurring in the output patterns and therefore reduce largely the spurious patterns. The derivation of DBAM is given and the stability of DBAM is proved. We also derive a learning algorithm for DBAM,which has iterative form and make the network learn new patterns easily. Compared with NBAM the present BAM can be easily implemented by software.展开更多
In this paper, we study an energy efficient multi-antenna unmanned aerial vehicle(UAV)-enabled half-duplex mobile relaying system under Rician fading channels. By assuming that the UAV follows a circular trajectory at...In this paper, we study an energy efficient multi-antenna unmanned aerial vehicle(UAV)-enabled half-duplex mobile relaying system under Rician fading channels. By assuming that the UAV follows a circular trajectory at fixed altitude and applying the decode-and-forward relaying strategy, we maximize the energy efficiency by jointly designing beamforming, power allocation, circular radius and flight speed, subject to the sum transmit power constraint on source node and UAV relay node. First, we maximize the end-to-end signal-to-noise ratio by jointly designing beamforming and statistical power allocation. Based on the obtained beamforming and power allocation results, we then obtain a semi closed-form expression of energy efficiency, and finally maximize energy efficiency by optimizing flight speed and circular radius, allowing optimal circular radius to be obtained via numerical computation. Numerical results demonstrate that the proposed scheme can effectively enhance the system energy efficiency.展开更多
Objective:This paper is to investigate functional connectivity differences between the abacus experts and control groups by using nonlinear processing method spatiotemporal Lyapunov exponent.Methods:11 right-handed he...Objective:This paper is to investigate functional connectivity differences between the abacus experts and control groups by using nonlinear processing method spatiotemporal Lyapunov exponent.Methods:11 right-handed healthy control children and 12 abacus children were undergone functional magnetic resonance imaging(fMRI).After preprocessing fMRI data with SPM,linear and nonlinear methods for connectivity analysis were both employed.Results:Connectivity differences between the two groups were statistically P<0.05 by the correlation method,while the P value by the nonlinear method were P<0.01.Conclusion:There are significant differences between the two groups in functional connectivity of bilateral occipital lobes.The nonlinear method proposed here seems to be more specific compared with the common linear correlation method.展开更多
文摘In this paper we propose a new discrete bidirectional associative memory (DBAM) which is derived from our previous continuous linear bidirectional associative memory (LBAM). The DBAM performs bidirectionally the optimal associative mapping proposed by Kohonen. Like LBAM and NBAM proposed by one of the present authors,the present BAM ensures the guaranteed recall of all stored patterns,and possesses far higher capacity compared with other existing BAMs,and like NBAM, has the strong ability to suppress the noise occurring in the output patterns and therefore reduce largely the spurious patterns. The derivation of DBAM is given and the stability of DBAM is proved. We also derive a learning algorithm for DBAM,which has iterative form and make the network learn new patterns easily. Compared with NBAM the present BAM can be easily implemented by software.
基金supported in part by the National Science Foundation (NSFC) for Distinguished Young Scholars of China with Grant 61625106the National Natural Science Foundation of China under Grant 61531011
文摘In this paper, we study an energy efficient multi-antenna unmanned aerial vehicle(UAV)-enabled half-duplex mobile relaying system under Rician fading channels. By assuming that the UAV follows a circular trajectory at fixed altitude and applying the decode-and-forward relaying strategy, we maximize the energy efficiency by jointly designing beamforming, power allocation, circular radius and flight speed, subject to the sum transmit power constraint on source node and UAV relay node. First, we maximize the end-to-end signal-to-noise ratio by jointly designing beamforming and statistical power allocation. Based on the obtained beamforming and power allocation results, we then obtain a semi closed-form expression of energy efficiency, and finally maximize energy efficiency by optimizing flight speed and circular radius, allowing optimal circular radius to be obtained via numerical computation. Numerical results demonstrate that the proposed scheme can effectively enhance the system energy efficiency.
文摘Objective:This paper is to investigate functional connectivity differences between the abacus experts and control groups by using nonlinear processing method spatiotemporal Lyapunov exponent.Methods:11 right-handed healthy control children and 12 abacus children were undergone functional magnetic resonance imaging(fMRI).After preprocessing fMRI data with SPM,linear and nonlinear methods for connectivity analysis were both employed.Results:Connectivity differences between the two groups were statistically P<0.05 by the correlation method,while the P value by the nonlinear method were P<0.01.Conclusion:There are significant differences between the two groups in functional connectivity of bilateral occipital lobes.The nonlinear method proposed here seems to be more specific compared with the common linear correlation method.
