排序方式: 共有20条查询结果,搜索用时 15 毫秒
1.
This article mainly explores a class of non-autonomous delayed Nicholson’s blowflies model with a nonlinear density-dependent mortality term. By combining Lyapunov function method with differential inequality approach, some novel assertions are gained to guarantee the existence and exponential stability of positive periodic solutions for the addressed model, which generalize and refine the corresponding results in some recent published literature. 相似文献
2.
3.
Emile Franc Doungmo Goufo 《Mathematical Methods in the Applied Sciences》2017,40(8):3055-3065
Evolution of human language and learning processes have their foundation built on grammar that sets rules for construction of sentences and words. These forms of replicator–mutator (game dynamical with learning) dynamics remain however complex and sometime unpredictable because they involve children with some predispositions. In this paper, a system modeling evolutionary language and learning dynamics is investigated using the Crank–Nicholson numerical method together with the new differentiation with non‐singular kernel. Stability and convergence are comprehensively proven for the system. In order to seize the effects of the non‐singular kernel, an application to game dynamical with learning dynamics for a population with five languages is given together with numerical simulations. It happens that such dynamics, as functions of the learning accuracy μ, can exhibit unusual bifurcations and limit cycles followed by chaotic behaviors. This points out the existence of fickle and unpredictable variations of languages as time goes on, certainly due to the presence of learning errors. More interestingly, this chaos is shown to be dependent on the order of the non‐singular kernel derivative and speeds up as this derivative order decreases. Hence, can people use that order to control chaotic behaviors observed in game dynamical systems with learning! Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
4.
In this paper, we investigate the global existence of almost surely positive solution to a stochastic Nicholson’s blowflies delay differential equation with regime switching, and give the estimation of the path. The results presented in this paper extend some corresponding results in Wang et al. Stochastic Nicholson’s blowflies delayed differential equations, Appl. Math. Lett. 87 (2019) 20–26 . 相似文献
5.
We study the global attractivity of the unique positive equilibrium of a population model with distributed delays and nonlinear death rate. Both delay dependent and delay independent criteria are obtained which generalize, unify and improve known criteria. These results will be applied to some models with bounded and unbounded death functions. 相似文献
6.
In this paper we propose parallel algorithm for the solution of partial differential equations over a rectangular domain using the Crank–Nicholson method by cooperation with the DuFort–Frankel method and apply it on a model problem, namely, the heat conduction equation. One of the well known parallel techniques in solving partial differential equations in cluster computing environment is the domain decomposition technique. Using this technique, the whole domain is decomposed into subdomains, each of them has its own boundaries that are called the interface points. Parallelization is realized by approximating interface values using the unconditionally stable DuFort–Frankel explicit scheme, and these values serve as Neumann boundary conditions for the Crank–Nicholson implicit scheme in the subdomains. The numerical results show that our algorithm is more accurate than the algorithm based on the forward explicit method to approximate the values of the interface points, especially, when we use a small number of time steps. Moreover, these numerical results show that increasing the number of processors which are used in the cluster, yields an increase in the algorithm speedup. 相似文献
7.
V. Kumaran A. Vanav Kumar I. Pop 《Communications in Nonlinear Science & Numerical Simulation》2010,15(2):300-311
In this paper a study is carried out to understand the transition effect of boundary layer flow: (1) due to a suddenly imposed magnetic field over a viscous flow past a stretching sheet and (2) due to sudden withdrawal of magnetic field over a viscous flow past a stretching sheet under a magnetic field. In both the cases the sheet stretches linearly along the direction of the fluid flow. Governing equations have been non-dimensionalised and the non-dimensionalised equations have been solved using the implicit finite difference method of Crank–Nicholson type. Comparison between the steady state exact solutions and the steady state computed solutions has been carried out. Graphical representation of the dimensionless horizontal velocity, vertical velocity and local skin friction profiles of the steady state and unsteady state has been presented. Computation has been carried out for various values of the magnetic parameter M. The obtained results has been interpreted and discussed. 相似文献
8.
9.
Luigi Fabbrizzi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(18):5868-5880
This Essay tells the colourful history of the invention of the pile by Alessandro Volta and of the subsequent discovery by William Nicholson of the electrolysis of water, carried out with the Voltaic pile (1800). Indeed, as a result of the dissemination of Volta's paper among London scientists, favoured by an incorrect behaviour of the President of the Royal Society, the article by Nicholson was published months before the publication of Volta's letter. The outstanding news that electricity could be generated by a simple and easy to build instrument (the pile) was printed also by daily newspapers, which favoured its spreading all over Europe and stimulated a multitude of enthusiast practitioners and amateurs to construct their own pile and to carry out the electrical decomposition of a variety of aqueous electrolytes. The correct chemical interpretation of the pile and of electrolysis had to wait for nearly one century, but in 1800 electrochemistry was born. 相似文献
10.
《Mathematical Methods in the Applied Sciences》2018,41(12):4841-4852
We study the local dynamics and supercritical Neimark‐Sacker bifurcation of a discrete‐time Nicholson‐Bailey host‐parasitoid model in the interior of . It is proved that if α>1, then the model has a unique positive equilibrium point , which is locally asymptotically focus, unstable focus and nonhyperbolic under certain parametric condition. Furthermore, it is proved that the model undergoes a supercritical Neimark‐Sacker bifurcation in a small neighborhood of the unique positive equilibrium point , and meanwhile, the stable closed curve appears. From the viewpoint of biology, the stable closed curve corresponds to the period or quasiperiodic oscillations between host and parasitoid populations. Some numerical simulations are presented to verify theoretical results. 相似文献