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排序方式: 共有523条查询结果,搜索用时 31 毫秒
91.
We propose a monomer adsorption model, in which only the monomers are allowed to diffuse and adsorb onto other clusters. By means of the generalized rate equation we investigate the kinetic behavior of the system with a special rate kernel. For the system without monomer input, the concentration aj(t) of the Aj clusters (j 〉 1) asymptotically retains a nonzero quantity, while for the system with monomer input, it decays with time and vanishes finally. We also investigate the kinetics of an interesting model with fixed-rate monomer adsorption. For the ease without monomer source, the evolution of the system will halt at a finite time; while the system evolves infinitely in time in the case with monomer source. Finally, we also suggest a connection between the fixed-rate monomer adsorption systems and growing networks. 相似文献
92.
走滑式断层地震的折迭突变模型 总被引:1,自引:1,他引:0
利用过势函数微分形式的途径,计入远场外力功的影响,对走滑式断层地震机制进行分析.研究表明:突变理论中折迭突变模型展示的性状,与走滑式断层地震的主要特征之间一一对应.折迭突变可对包括震前、震后围岩-断层系统稳定性描述在内的断层失稳起、终点位置、断层失稳错距等作出描述.给出3种性状可相互印证的断层失稳围岩弹性能释放量图解.走滑式断层地震强度与围岩压力及围岩断层的刚度比等有关,围岩压力大、刚度比小、主切应力轴与发震断层面夹角大,则地震强度大. 相似文献
93.
V型原子与光场拉曼相互作用传送未知原子态 总被引:10,自引:0,他引:10
未知量子态从一个地方到另一个地方的隐形传送在量子信息领域中有非常重要的作用,提出了一种利用简并V型三能级原子与振幅很大的单模相干态腔场的拉曼相互作用来传送未知原子态的方案。 相似文献
94.
95.
一类可变服务率的车辆排队特征分析 总被引:2,自引:0,他引:2
本文提出一类服务率随排队车辆数变化的单通道车辆排队模型 ;运用排队理论 ,分析了一种经常可以在高速公路收费站、加油站、平面交叉口等场所看到的随机服务现象 ,充分考虑了服务率与车辆排队数之间的相关特性 ,得出了较切合实际的车辆排队模型 ,给出了各参数指标的数学表达式 ,并且具体实例加以比较说明 相似文献
96.
An effective teleportation scheme for an unknown ionic internal state
via trapped ions is proposed without joint Bell-state measurement
(BSM). In the constructed quantum channel process, we make use of
entanglement swapping to avoid decrease in entanglement during
the distributing of particles. Thus our scheme provides new prospects
for quantum teleportation in a longer distance. The distinct
advantage of our scheme is insensitive to the heating of vibrational
mode. Furthermore, our scheme has no any individual optical access,
and the successful probability also can reach 1. 相似文献
97.
Synchronization between two different noise-perturbed chaotic systems with unknown parameters 下载免费PDF全文
In this paper, a general method of synchronizing noise-perturbed chaotic systems with unknown parameters is proposed. Based on the LaSalle-type invariance principle for stochastic differential equations and by employing a combination of feedback control and adaptive control, some sufficient conditions of chaos synchronization between these noise-perturbed systems with unknown parameters are established. The model used in the research is the chaotic system, but the method is also applicable to the hyperchaotic systems. Unified system and noise-perturbed RSssler system, hyperchaotic Chen system and nolse-perturbed hyperchaotic RSssler system are taken for illustrative examples to demonstrate this technique.[第一段] 相似文献
98.
CHEN Li-Mei CAO Li WU Da-Jin GE Guo-Qin 《理论物理通讯》2005,44(4):638-642
The effect on intensity correlation time T by input signal is studied for gain-noise model of a single-mode laser driven by colored pump noise and colored quantum noise with colored cross-correlation with a bias signal modulation in this paper. By using the linear approximation method, we detect that there exists maximum (i.e., resonance) in the curve of the intensity correlation time T upon bias current io when the noise correlation coefficient λ is positive; and there exists minimum (i.e., suppression) in the T-io curve when λ is negative. And whenλ is zero, T increases monotonously with increasing io. Furthermore, the curve of T upon the signal frequency Ω is also studied. Our study shows that no matter what the value of λ is, there exists minimum (i.e., suppression) in the T-Ω curve. 相似文献
99.
Physical mechanism of the chaotic detection of the unknown frequency of weak harmonic signal and effects of damping ratio on the detection results 总被引:3,自引:0,他引:3 下载免费PDF全文
In the zero-order approximation, we use the perturbation method of parameter with small magnitude to prove that the harmonic frequency in the solution of the equation is close to that of the driving force when the chaotic system from Duffing-Holmes equation stays in the stable periodic state, which is the physical mechanism of the detection of the unknown frequency of weak harmonic signal using the chaotic theory. The result of the simulation experiment shows that the method proposed in this paper, by which one can determine the frequency of the stable system from the number of circulation change of the phase state directionally across a fixed phase state point (x,\dot{x}) in fixed simulation time period, is successful. Analyzing the effects of the damping ratio on the chaotic detection result, one can see that for different frequency ranges it is necessary to carefully choose corresponding damping ratio α. 相似文献
100.