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931.
Synchronization of stochastically hybrid coupled neural networks with coupling discrete and distributed time-varying delays
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A general model of linearly stochastically coupled identical connected neural networks with hybrid coupling is proposed, which is composed of constant coupling, coupling discrete time-varying delay and coupling distributed timevarying delay. All the coupling terms are subjected to stochastic disturbances described in terms of Brownian motion, which reflects a more realistic dynamical behaviour of coupled systems in practice. Based on a simple adaptive feedback controller and stochastic stability theory, several sufficient criteria are presented to ensure the synchronization of linearly stochastically coupled complex networks with coupling mixed time-varying delays. Finally, numerical simulations illustrated by scale-free complex networks verify the effectiveness of the proposed controllers. 相似文献
932.
This paper studies the two-vibron bound states in the β- Fermi Pasta-Ulam model by means of the number conserving approximation combined with the number state method. The results indicate that on-site, adjacent-site and mixed two-vibron bound states may exist in the model. Specially, wave number has a significant effect on such bound states, which may be considered as the quantum effects of the localized states in quantum systems. 相似文献
933.
High-power operation of diode-pumped fiber lasers at wavelength near 2μm are demonstrated with short length of heavily Tm3 -doped silica glass fibers. With 7-cm long fiber, a laser at near 2 μm is obtained with the threshold of 135 mW, maximum output power of 1.09 W, and slope efficiency of 9.6% with respect to the launched power from a laser diode at 790 nm. The output stability of this fiber laser is within 5%.The dependence of the performance of fiber lasers on the operation temperature and cavity configuration parameters is also investigated. 相似文献
934.
935.
A high-repetition-rate eye-safe optical parametric oscillator (OPO), using a non-critically phase-matched KTP crystal intracavity pumped by a passively Q-switched Nd:GdVO4/Cr^4+ :YAG laser, is experimentally demonstrated. The conversion efficiency for the average power is 7% from pump diode input to OPO signal output and the slope efficiency is up to 10.3%. With an incident pump power of 7,3 W, the compact intracavity OPO (IOPO) cavity, operating at 15 kHz, produces an average power of 0.57 W at 1570 nm with a pulse width as short as 6 ns. The peak power at 1570 nm is higher than 6.3 kW. 相似文献
936.
937.
Letn2. The authors establish theL
2(
n
)-boundedness of singular integrals with variable rough Calderón-Zygmund kernels associated to surfaces satisfying some conditions.The research is supported in part by the NNSF and the SEDF of China. 相似文献
938.
The f-depth of an ideal on a module 总被引:2,自引:0,他引:2
Rencai Lü Zhongming Tang 《Proceedings of the American Mathematical Society》2002,130(7):1905-1912
Let be an ideal of a Noetherian local ring and a finitely generated -module. The f-depth of on is the least integer such that the local cohomology module is not Artinian. This paper presents some part of the theory of f-depth including characterizations of f-depth and a relation between f-depth and f-modules.
939.
Tang F Wang J Liu D Yuan G Liu Y Jin Zhu C Fen Zhao Y 《Rapid communications in mass spectrometry : RCM》2002,16(11):1035-1039
The electrospray ionization tandem mass spectrometric (ESI-MS/MS) characteristics and fragmentation mechanisms of eight distamycin analogues containing N-methylpyrrole and N-methylimidazole were investigated. The members of two isomeric groups of distamycin analogues with the same elemental composition can be distinguished by MS/MS spectra of protonated molecules and of significant fragment ions. 相似文献
940.
Akikawa H Ajimura S Chrien RE Eugenio PM Franklin GB Franz J Gang L Imai K Khaustov P May M Pile PH Quinn B Rusek A Sasao J Sawafta RI Schmitt H Tamura H Tang L Tanida K Yuan L Zhou SH Zhu LH Zhu XF 《Physical review letters》2002,88(8):082501
With a germanium detector array (Hyperball), we observed two gamma-ray peaks corresponding to the two transitions (5/2(+)-->1/2(+) and 3/2(+)-->1/2(+)) in the (9)(Lambda)Be hypernucleus which was produced by the 9Be(K-,pi(-)) reaction. The energies of the gamma rays are 3029 +/- 2 +/- 1 keV and 3060 +/- 2 +/- 1 keV. The energy difference was measured to be 31.4(+2.5)(-3.6) keV, which indicates a very small Lambda-spin-dependent spin-orbit force between a Lambda and a nucleon. This is the smallest level splitting by far ever measured in a hypernucleus. 相似文献