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251.
非线性非均衡蛛网模型的动态分析   总被引:5,自引:0,他引:5  
描述单商品市场价格波动的蛛网模型是动态经济分析中的经典模型 ,证明了由模型 ( )所生成的价格序列在一定的条件下不会出现 3以上周期运动和混沌现象 ,并对其进行稳定性分析 ,得到模型关于均衡价格稳定的六个判别定理 .  相似文献   
252.
Local structure theory calculations7 are applied to the study of cellular automata on the two-dimensional hexagonal lattice. A particular hexagonal lattice rule denoted (3422) is considered in detail. This rule has many features in common with Conway'sLife. The local structure theory captures many of the statistical properties of this rule; this supports hypotheses raised by a study ofLife itself(6). As inLife, the state of a cell under (3422) depends only on the state of the cell itself and the sum of states in its neighborhood at the previous time step. This property implies that evolution rules which operate in the same way can be studied on different lattices. The differences between the behavior of these rules on different lattices are dramatic. The mean field theory cannot reflect these differences. However, a generalization of the mean field theory, the local structure theory, does account for the rule-lattice interaction.  相似文献   
253.
种改进的谐振参数扰动法来控制混沌,该混沌控制方法引入了基于非线性映射的调制,其控制目标可以是任意周期的轨道,而不是原混沌吸引子中的嵌入轨道。作为一个应用实例,文中描述了该方法在电流模式控制dc/dc变换器中的应用结果。  相似文献   
254.
The present paper examines the influence of the forcing frequency on the response of a randomly perturbed Hodgkin-Huxley system in the realm of suprathreshold amplitudes. Our results show that, in the presence of noise, the choice of driving frequency can seriously affect the precision of the external information transmission. At the same level of noise the precision can either decrease or increase depending on the driving frequency. We demonstrate that the destructive influence of noise on the interspike interval can be effectively reduced. That is, with driving signals in certain frequency ranges, the system can show stable periodic spiking even for relatively large noise intensities. Here, the most accurate transmission of an external signal occurs. Outside these frequency ranges, noise of the same intensity destroys the regularity of the spike trains by suppressing the generation of some spikes. On the other hand, we show that noise can have a reconstructive role for certain driving frequencies. Here, increasing noise intensity enhances the coherence of the neuronal response.  相似文献   
255.
本文研究了具有不同耦合强度且带有时滞的振子网络上的同步问题.我们给出了该网络同步状态的稳定性准则,证实了其同步状态的稳定性与网络的拓扑性无关.最后,通过数值模拟验证了我们的理论结果.  相似文献   
256.
Bala Sundaram 《Pramana》1997,48(2):469-486
I will show how aspects of quantum chaology are relevant even in a seemingly well understood quantum phenomenon like the photoelectric effect. This example together with recent experiments in atom optics are used to define and discuss the larger questions, recent progress made by us in resolving some of these issues and future directions.  相似文献   
257.
B R Sitaram 《Pramana》1997,49(2):193-197
In this communication, we investigate the behavior of the derivatives of invariants for Hamiltonian systems, using information derived from an analysis of the Liapunov exponents of the system. We show that under certain conditions on the analyticity properties of the solutions of the equations of motion, it is possible to construct 2n invariants of motion which are guaranteed to beC as functions of phase space and time in a suitably defined domainD.  相似文献   
258.
Finite clusters of atoms or molecules, typically composed of about 50 particles (and often as few as 13 or even less) have proved to be useful prototypes of systems undergoing phase transitions. Analogues of the solid-liquid melting transition, surface melting, structural phase transitions and the glass transition have been observed in cluster systems. The methods of nonlinear dynamics can be applied to systems of this size, and these have helped elucidate the nature of the microscopic dynamics, which, as a function of internal energy (or ‘temperature’) can be in a solidlike, liquidlike, or even gaseous state. The Lyapunov exponents show a characteristic behaviour as a function of energy, and provide a reliable signature of the solid-liquid melting phase transition. The behaviour of such indices at other phase transitions has only partially been explored. These and related applications are reviewed in the present article.  相似文献   
259.
继承异常用来描述在并发面向对象语言中继承与并发的冲突.对继承异常做了系统的分析,给出一种新的分类.提出在一并发对象中将同步部分与顺序部分分离,生成两个对象,通过将同步代码放入一单独对象,将继承过程分为顺序部分和同步部分,这种分离大大地减少了继承异常的发生.  相似文献   
260.
卢俊国  席裕庚 《中国物理》2005,14(2):274-278
A novel chaos communication method is proposed based on synchronization of discrete-time chaotic systems. This method uses a full-order state observer to achieve synchronization and secure communication between the transmitter and the receiver. Further, we present a multiple-access chaotic digital communication method by combining the observer with the on-line least square method. Simulation results are also given for illustration.  相似文献   
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