排序方式: 共有14条查询结果,搜索用时 15 毫秒
1.
Yan Ziqian 《东北数学》1995,(3)
ThreeClassesofReaction-DiffusionSystemswithNeumannBoundaryCondition¥(严子谦)YanZiqian(DepartmentofMathematics,JilinUniversity,Ch... 相似文献
2.
In the present work we demonstrate that FTIR-spectroscopy is a powerful tool for the time resolved and noninvasive measurement of multi-substrate/product interactions in complex metabolic networks as exemplified by the oscillating glycolysis in a yeast extract. Based on a spectral library constructed from the pure glycolytic intermediates, chemometric analysis of the complex spectra allowed us the identification of many of these intermediates. Singular value decomposition and multiple level wavelet decomposition were used to separate drifting substances from oscillating ones. This enabled us to identify slow and fast variables of glycolytic oscillations. Most importantly, we can attribute a qualitative change in the positive feedback regulation of the autocatalytic reaction to the transition from homogeneous oscillations to travelling waves. During the oscillatory phase the enzyme phosphofructokinase is mainly activated by its own product ADP, whereas the transition to waves is accompanied with a shift of the positive feedback from ADP to AMP. This indicates that the overall energetic state of the yeast extract determines the transition between spatially homogeneous oscillations and travelling waves. 相似文献
3.
本文对含非局部源反应扩散方程的定常问题讨论了正解的存在性,对依赖时间的解,给出了整体存在条件和有限时间爆破条件。 相似文献
4.
Mark Freidlin 《Journal of statistical physics》2006,122(2):333-349
We consider reaction-convection in a stationary incompressible flow which is close to a planar motion. Under certain conditions,
we introduce the notion of relative entropy for such a deterministic flow to describe the motion of the spot occupied by an
ingredient.
The work was supported in part by an NSF grant DMS0503950. 相似文献
5.
建立了一个基于平均场动力学的微分方程组和反应—扩散模型的双层耦合网络模型,用来分析、预测及评价地球生物与环境的健康问题。在双层耦合网络模型中,根据地球地理和气候分布,将全球划分为九块区域,并以此作为全球网络的节点;同时,七个具有代表性的反映地球健康状况的元素,如人口密度、森林、空气质量、生物多样性等,被挑选出作为元素网络的节点。再通过平均场动力学微分方程,建立并描述了各个元素间的联系与相互作用;利用数据确定模型参数,从而完善模型,最后,以此模型完成寻找临界点、灵敏度分析、网络结构分析、引入不确定性等工作。 相似文献
6.
Fujita型反应扩散方程组整体解的存在性、非存在性与渐近性质 总被引:5,自引:0,他引:5
本文研究 Fujita型反应扩散方程组的初值问题:ut-△u=a1u~α1-1u+b1v~β1-1v,vt-△v=a2u~α2-1u+b2v~β2-1v,u(X,0)=u0(X),V(X,0)=V0(X),(X,t)R~N x R~+,其中 ai,bi≥ 0, αi,βi≥ 1(i= 1,2),给出了非负整体 L~p解与古典解存在性与非存在性的一系列充分条件,并讨论了解的渐近性质.本文所用方法和所得结果与已有的工作[1-4],有很大的不同,不但在某些方面推广了[1-5],而且从某些方面改进了[1]的结果。 相似文献
7.
We study reaction-diffusion systems where diffusion is by jumps whose sizes are distributed exponentially. We first study
the Fisher-like problem of propagation of a front into an unstable state, as typified by the A+B → 2A reaction. We find that
the effect of fluctuations is especially pronounced at small hopping rates. Fluctuations are treated heuristically via a density
cutoff in the reaction rate. We then consider the case of propagating up a reaction rate gradient. The effect of fluctuations
here is pronounced, with the front velocity increasing without limit with increasing bulk particle density. The rate of increase
is faster than in the case of a reaction-gradient with nearest-neighbor hopping. We derive analytic expressions for the front
velocity dependence on bulk particle density. Computer simulations are performed to confirm the analytical results. 相似文献
8.
本文研究了生态学中一类非线性反应扩散方程组的小波Galerkin方法,利用多尺度分析的尺度空间作为试探函数空间,建立显式离散模型,证明了小波逼近解的存在唯一性,并进行了误差分析,最后给出数值模拟的例子. 相似文献
9.
ONTHEBOUNDEDANDUNBOUNDEDSOLUTIONSOFONEDIMENSIONALNONLINEARREACTION-DIFFUSIONPROBLEM¥GEWEIGAOR.O.WEBERAbstract:Theexistenceofb... 相似文献
10.
The aim of this work is to study the propagation of a curved premixed flame in an infinite two-dimensional tube. The numerical method combines some features of the finite-element and of the finite-difference methods, and uses a moving adaptive grid procedure in order to reduce the computational costs. 相似文献