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61.
62.
C. Biely R. Hanel S. Thurner 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,67(3):285-289
We consider social systems in which agents are not only characterized by their states but also have the freedom to choose
their interaction partners to maximize their utility. We map such systems onto an Ising model in which spins are dynamically
coupled by links in a dynamical network. In this model there are two dynamical quantitieswhich arrange towards a minimum energy
state in the canonical framework:the spins, si, and the adjacency matrix elements, cij.The model is exactly solvable because microcanonical partition functions reduce to productsof binomial factors as a direct
consequence of the cij minimizing energy. We solve the system for finite sizes and for the two possible thermodynamic limits and discussthe phase
diagrams. 相似文献
63.
Chen Chao Ji Kun 《高校应用数学学报(英文版)》2007,22(4):393-404
In this paper,a nonlinear nonautonomous predator-prey dispersion model with continuous distributed delay is studied,where all parameters are time-dependent.In this system consisting of n-patches the prey species can disperse among n-patches,but the predator species is confined to one patch and cannot disperse.It is proved that the system is uniformly persistent under any dispersion rate effect.Furthermore,some sufficient conditions are established for the existence of a unique almost periodic solution of the system.The example shows that the criteria in the paper are new,general and easily verifiable. 相似文献
64.
Mo Jiaqi Zhang Weijiang Chen Xianfeng 《高校应用数学学报(英文版)》2007,22(4):421-424
The solvability of nonlinear elliptic equation with boundary perturbation is consid- ered.The perturbed solution of original problem is obtained and the uniformly valid expansion of solution is proved. 相似文献
65.
66.
67.
PARALLELNONLINEARMULTISPLITTINGRELAXATIONMETHODSWANGDERENANDBAIZHONGZHI(DepartmentofMathematics,ShanghaiUniversityofSciencean... 相似文献
68.
This paper analyzes the high bit-rate optical pulse trasmission in single mode optical fiber with chromatic dispersion, polarization mode dispersion (small random birefringence) and nonlinearity. Numerical method employed can precisely describe their interactive effect on transmission performance. Different dispersion maps and the related performance are analysed. Various simulation results and discussion are given. The results show that chromatic dispersion compensation should be carefully designed. Appropriate dispersion management can also alleviate the effect of polarization mode dispersion. 相似文献
69.
ZHENGXin CHENTian-Lun 《理论物理通讯》2003,40(2):165-168
In the research of using Radial Basis Function Neural Network (RBF NN) forecasting nonlinear time series, we investigate how the different clusterings affect the process of learning and forecasting. We find that k-means clustering is very suitable. In order to increase the precision we introduce a nonlinear feedback term to escape from the local minima of energy, then we use the model to forecast the nonlinear time series which are produced by Mackey-Glass equation and stocks. By selecting the k-means clustering and the suitable feedback term, much better forecasting results are obtained. 相似文献
70.
In this note new Rosenbrock methods for ODEs, DAEs, PDEs and PDAEs of index 1 are presented. These solvers are of order 3,
have 3 or 4 internal stages, and fulfil certain order conditions to obtain a better convergence if inexact Jacobians and approximations
of
are used. A comparison with other Rosenbrock solvers shows the advantages of the new methods.
AMS subject classification (2000) 34A09, 65L80 相似文献