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51.
The duplication and divergence process is ubiquitous in nature and man-made networks. Motivated by the duplication-divergence mechanism which depicts the growth of protein networks, we propose a weighted network model in which topological evolution is coupled with weight dynamics. Large scale numerical results indicate that our model can naturally generate networks with power-law-like distributions of degree, strength and weight. The degree-strength correlation is illustrated as well. These properties are in agreement well with empirical data observed in real-world systems. Furthermore, by altering the retention probability δ, weighted, structured exponential networks are realized. 相似文献
52.
We propose an adaptive adjustment mechanism for synchronizing complex networks, in particular for sociological or/and biological systems. We do not take it for granted that a dynamical system is put on isolated nodes and they are coupled with each other by one (or more) variable(s), as employed in most previous models. As a replacement, we suppose that each node may have any finite number of possible states, and their evolutions with time are determined by their nearest-neighbouring (or even second-nearest-neighbouring, etc) nodes in an adaptive adjustment mechanism. It is found that synchronization can be achieved for almost all connected networks and that the scale-free property can evidently improve the synchronizing speed. 相似文献
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3族新的不含紧优与几乎紧优的有向双环网络无限族 总被引:2,自引:0,他引:2
给出了3族新的不含紧优与几乎紧优的有向双环网络. 相似文献
56.
Cascade Grating Structure for Increasing the Channel Number on Holographic Demultiplexer 总被引:1,自引:0,他引:1 下载免费PDF全文
Jun Won AN 《中国物理快报》2006,23(6):1459-1461
The expansion capability of the channel number in the optical demultiplexer using two cascaded photopolymer volume gratings is reported. It could be accomplished by designing of two gratings with different spectral range. As a result of the experiment, a 0.4-nm-spaced 130-channel demultiplexer with the channel uniformity of 3.5 dB, the 3 riB-bandwidth of 0.12nm, and the channel crosstalk of-20 dB is experimentally demonstrated. 相似文献
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本文给出了一种方法用于构造k-紧优双环网络无限族(k≥1),并用此方法构造出了4族3-紧优无限族,3族新的4-紧比无限族,3族5-紧优无限族及2族6-紧优无限族. 相似文献
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We introduce a feedback mechanism to study the spreading of an epidemic by analytical methods and large scale simulations in exponential networks. It is found that introducing the feedback mechanism can reduce the density of infected individuals, Furthermore, it does not change the epidemic threshold (critical point) λc. These results can help us to understand epidemic spreading phenomena on social networks more practically and design appropriate strategies to control social infections. 相似文献
59.
Af型自由基均聚反应的固化理论(Ⅱ):凝胶网络的结构参数 总被引:1,自引:1,他引:0
用高分子反应统计理论,给出Af型自由基均聚反应在不同反应程度时的弹性有效链及悬吊链的链数,链节数和平均链长,也得到了体系的有效交联点数和弹性模量,进而给出弹性有效链的数量和重量分数,以此可进一步揭示该反应体系凝胶网络的粘弹性及相关的力学性质。 相似文献
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