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91.
Neural Signal Tuned by Random Long-range Connections in Coupled FitzHugh-Nagumo Neurons Systems 下载免费PDF全文
We investigate the effect of random long-range connections on signal propagation in an array of coupled FitzHugh- Nagumo (FHN) neurons. The neural network can be obtained by randomly adding a small fraction of shortcuts in an originally locally coupled one-dimensional chain. It is shown that when the first neuron is subjected to external stimuli, it fires and excites its connected neighbours, such that the neural signal may propagate along the chain favoured by the shortcuts. Moreover, there exists an optimal number of shortcuts which can lead to the most synchronous behaviour. In addition, how the region of the fraction of shortcuts varies with the coupling strength is also discussed. These results suggest that topological disorder in the neural network may play a vital role in helping information processing in living systems. 相似文献
92.
The conceptual design of a cryogenic system at temperature 2 K for the Peking University Free Electron Laser (PKU-FEL) facility is carried out. In order to minimize the scale of the cryogenic system and the running cost, the superconducting accelerator and the superconducting injector will mainly run at a long-pulsed mode. Optimization of the 2-K cryogenic system is carried out based on the heat load estimation and running parameters. Total cooling power of 52.5 W for the long-pulsed mode is necessary for the PKU cryogenic system. The PKU cryogenic system will be the first 2-K system for accelerators in China and will provide experience for similar facilities. 相似文献
93.
This paper is devoted to the study of the underlying linearities of the coupled
Harry--Dym (cHD) soliton hierarchy, including the well-known cHD equation. Resorting
to the nonlinearization of Lax pairs, a family of finite-dimensional Hamiltonian
systems associated with soliton equations are presented, constituting the
decomposition of the cHD soliton hierarchy. After suitably introducing the
Abel--Jacobi coordinates on a Riemann surface, the cHD soliton hierarchy can be
ultimately reduced to linear superpositions,
expressed by the Abel--Jacobi variables. 相似文献
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96.
FAN Hong-Yi LI Chao 《理论物理通讯》2006,46(1):46-50
Based on the technique of integral within an ordered product of nonlinear bosonic operators we construct a kind of tripartite nonlinear entangled states, which can make up a complete set. As its application, we also derive nonlinear 3-mode charge-related entangled state. The essential point for constructing these states lies in choosing the appropriate charge operator. 相似文献
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99.
A quasi-cyclic low-density parity check (QC-LDPC) code is constructed by an improved stability of the shortest cycle algorithm for 160-Gb/s non-return zero differential quadrature phase shift keying (NRZ- DQPSK) optical transmission system with the fiber-based optical parametric amplifier (FOPA). The QC- --14 d LDPC code with stability of the shortest cycle reduces the bit error ratio (BER) to 10 an restrains the error floor effectively. 相似文献
100.
We report a 3.75-Gb/s visible light communication(VLC) system thatusessingle-carrier frequency-domain equalization(SC-FDE) based on a single red–green–blue(RGB) light-emitting diode(LED),with the measured bit error rates(BERs) under a pre-forward-error-correction threshold of 3.8×10-3.The fundamental characteristics of an RGB-LED-based VLC system are measured.We also compare SC-FDE with OFDM in terms of peak-to-average power ratio and BER performance,which shows that SC-FDE outperforms the OFDM modulation scheme. 相似文献