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71.
Dynamics of a stochastic rumor propagation model incorporating media coverage and driven by Lévy noise 下载免费PDF全文
Liang-An Huo 《中国物理 B》2021,30(8):80201-080201
With the development of information technology, rumors propagate faster and more widely than in the past. In this paper, a stochastic rumor propagation model incorporating media coverage and driven by Lévy noise is proposed. The global positivity of the solution process is proved, and further the basic reproductive number R0 is obtained. When R0 < 1, the dynamical process of system with Lévy jump tends to the rumor-free equilibrium point of the deterministic system, and the rumor tends to extinction; when R0 > 1, the rumor will keep spreading and the system will oscillate randomly near the rumor equilibrium point of the deterministic system. The results show that the oscillation amplitude is related to the disturbance of the system. In addition, increasing media coverage can effectively reduce the final spread of rumors. Finally, the above results are verified by numerical simulation. 相似文献
72.
Results of classical molecular dynamics simulations are presented for the re-orientational dynamics of water hydrogen bonded to perchlorate anion. Different mechanisms of bond formation are presented. Due to its regular tetrahedron geometry the perchlorate anion can make classical as well as bifurcated and trifurcated hydrogen bonds. The angular variation of water in the first solvation shell of perchlorate suggests the transitional character of multi-centred hydrogen bonds. As a result water molecules can slide around the anion. 相似文献
73.
高温超导磁通跳跃过程中的磁致伸缩效应 总被引:1,自引:0,他引:1
文中基于超导磁通动力学理论,考虑电磁力与热激活对磁通运动的影响,基本模型包括由等效电阻率随超导体温度和磁场变化的磁通扩散方程,以及比热随超导体温度变化的热传导方程组成.在此基础上,用数值方法求解了这组非线性磁热耦合方程,主要研究了有磁通跳跃状发生状态时环境温度和外磁场速度对于高温超导磁致伸缩的影响.结果表明:磁通进入超... 相似文献
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In this paper we obtain fixed point and common fixed point theorems for self- mappings defined on a metric-type space, an ordered metric-type space or a normal cone metric space. Moreover, some examples and an application to integral equations are given to illustrate the usability of the obtained results. 相似文献
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In this paper, we have studied the necessary maximum principle of stochastic optimal control problem with delay and jump diffusion. 相似文献
78.
E. Pindza K.C. Patidar E. Ngounda 《Numerical Methods for Partial Differential Equations》2014,30(4):1169-1188
We propose a novel numerical method based on rational spectral collocation and Clenshaw–Curtis quadrature methods together with the “” transformation for pricing European vanilla and butterfly spread options under Merton's jump‐diffusion model. Under certain assumptions, such model leads to a partial integro‐differential equation (PIDE). The differential and integral parts of the PIDE are approximated by the rational spectral collocation and the Clenshaw–Curtis quadrature methods, respectively. The application of spectral collocation method to the PIDE leads to a system of ordinary differential equations, which is solved using the implicit–explicit predictor–corrector (IMEX‐PC) schemes in which the diffusion term is integrated implicitly, whereas the convolution integral, reaction, advection terms are integrated explicitly. Numerical experiments illustrate that our approach is highly accurate and efficient for pricing financial options.Copyright © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 1169–1188, 2014 相似文献
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雷贤才 《数学的实践与认识》2014,(3)
目的是研究Banach空间中无限族非扩张映象和非扩张半群的强收敛问题.为此提出一个改进的迭代序列,在适当条件下,某些强收敛定理被证明.结果改进和推广了一些人的最新结果. 相似文献