共查询到20条相似文献,搜索用时 15 毫秒
1.
A limited resource model of fault-tolerant capability
against cascading failure of complex network 总被引:1,自引:0,他引:1
P. Li B.-H. Wang H. Sun P. Gao T. Zhou 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,62(1):101-104
We propose a novel capacity model for complex networks
against cascading failure. In this model, vertices with both higher
loads and larger degrees should be paid more extra capacities, i.e.
the allocation of extra capacity on vertex i will be proportional
to ki
γ , where ki is the degree of vertex i
and γ > 0 is a free parameter. We have applied this model on
Barabási-Albert network as well as two real transportation
networks, and found that under the same amount of available
resource, this model can achieve better network robustness than
previous models. 相似文献
2.
S. Lehmann L. K. Hansen 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(1):83-88
We study community structure of networks. We have developed a scheme
for maximizing the modularity Q [Newman and Girvan, Phys. Rev. E 69, 026113 (2004)] based on mean field methods. Further, we have defined a simple family of random networks with community structure;
we understand the behavior of
these networks analytically. Using these networks, we show how the
mean field methods display better performance than previously known
deterministic methods for optimization of Q. 相似文献
3.
Zhongzhi Zhang Shuigeng Zhou Zhan Su Tao Zou Jihong Guan 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(1):141-147
In this paper, we define a stochastic Sierpinski gasket, on the basis of which we construct a network called random Sierpinski
network (RSN). We investigate analytically or numerically the statistical characteristics of RSN. The obtained results reveal
that the properties of RSN is particularly rich, it is simultaneously scale-free, small-world, uncorrelated, modular, and
maximal planar. All obtained analytical predictions are successfully contrasted with extensive numerical simulations. Our
network representation method could be applied to study the complexity of some real systems in biological and information
fields. 相似文献
4.
Zhongzhi Zhang Shuigeng Zhou Lichao Chen 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(3):337-344
We present a family of scale-free network model consisting
of cliques, which is established by a simple recursive algorithm. We
investigate the networks both analytically and numerically. The
obtained analytical solutions show that the networks follow a
power-law degree distribution, with degree exponent continuously
tuned between 2 and 3. The exact expression of clustering
coefficient is also provided for the networks. Furthermore, the
investigation of the average path length reveals that the networks
possess small-world feature. Interestingly, we find that a special
case of our model can be mapped into the Yule process. 相似文献
5.
S.-W. Son H. Jeong J. D. Noh 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(3):431-437
We propose a method to determine the community
structure of a complex network. In this method the ground state
problem of a ferromagnetic random field Ising model is considered
on the network with the magnetic field Bs = +∞, Bt =
-∞, and Bi≠s,t=0 for a node pair s and t. The
ground state problem is equivalent to the so-called maximum flow
problem, which can be solved exactly numerically with the help of
a combinatorial optimization algorithm. The community structure is
then identified from the ground state Ising spin domains for all
pairs of s and t. Our method provides a criterion for the
existence of the community structure, and is applicable equally
well to unweighted and weighted networks. We demonstrate the
performance of the method by applying it to the Barabási-Albert
network, Zachary karate club network, the scientific collaboration
network, and the stock price correlation network.
(Ising, Potts, etc.) 相似文献
6.
In this paper, we propose an evolving Sierpinski gasket, based on which we establish a model of evolutionary Sierpinski networks (ESNs) that unifies deterministic Sierpinski network [Z.Z. Zhang, S.G. Zhou, T. Zou, L.C. Chen, J.H. Guan, Eur. Phys. J. B 60 (2007) 259] and random Sierpinski network [Z.Z. Zhang, S.G. Zhou, Z. Su, T. Zou, J.H. Guan, Eur. Phys. J. B 65 (2008) 141] to the same framework. We suggest an iterative algorithm generating the ESNs. On the basis of the algorithm, some relevant properties of presented networks are calculated or predicted analytically. Analytical solution shows that the networks under consideration follow a power-law degree distribution, with the distribution exponent continuously tuned in a wide range. The obtained accurate expression of clustering coefficient, together with the prediction of average path length reveals that the ESNs possess small-world effect. All our theoretical results are successfully contrasted by numerical simulations. Moreover, the evolutionary prisoner’s dilemma game is also studied on some limitations of the ESNs, i.e., deterministic Sierpinski network and random Sierpinski network. 相似文献
7.
S. Zhang X.-M. Ning X.-S. Zhang 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):67-74
There has been a quickly growing interest in properties of complex
networks, such as the small world property, power-law degree
distribution, network transitivity, and community structure, which
seem to be common to many real world networks. In this study, we
consider the community property which is also found in many real
networks. Based on the diffusion kernels of networks, a hierarchical
clustering approach is proposed to uncover the community structure
of different extent of complex networks. We test the method on some
networks with known community structures and find that it can detect
significant community structure in these networks. Comparison with
related methods shows the effectiveness of the method. 相似文献
8.
J. D. Noh 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,66(2):251-257
We study a scaling property of the number Mh(N) of loops of size h in
complex networks with respect to a network size N.
For networks with a bounded second moment of degree,
we find two distinct scaling behaviors:
Mh(N) ~ (constant) and
Mh(N) ~ lnN as N increases.
Uncorrelated random networks specified only with a degree distribution
and Markovian networks specified only with a nearest neighbor
degree-degree correlation display the former scaling behavior, while
growing network models display the latter.
The difference is attributed
to structural correlation that cannot be captured by a short-range
degree-degree correlation. 相似文献
9.
L. Wu S. Zhu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(1):87-93
Load-dependent random walks are used to investigate the evolution of
load distribution in transportation network systems. The walkers hop
to a node according to node load of the last time step. The
preference of walks leads to a change in the load distribution. It
changes from degree-dependent distribution in the case of
non-preference walks to eigenvector-centrality-dependent
distribution. By numerical simulations, it is shown that the network
heterogeneity has a influence on the effect of walk preference. In
the cascading failure phenomenon, an appropriate degree correlation
can guarantee a low risk of cascading failures. 相似文献
10.
C.-L. Tang W.-X. Wang X. Wu B.-H. Wang 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,53(3):411-415
We study effects of average degree on cooperation in
the networked prisoner's dilemma game. Typical structures are
considered, including random networks, small-world networks and
scale-free networks. Simulation results show that the average
degree plays a universal role in cooperation occurring on all
these networks, that is the density of cooperators peaks at some
specific values of the average degree. Moreover, we investigated
the average payoff of players through numerical simulations
together with theoretical predictions and found that simulation
results agree with the predictions. Our work may be helpful in
understanding network effects on the evolutionary games. 相似文献
11.
F. Nisbach M. Kaiser 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(2):185-191
Many networks extent in space, may it be metric (e.g. geographic) or non-metric (ordinal). Spatial network growth, which depends
on the distance between nodes, can generate a wide range of topologies from small-world to linear scale-free networks. However,
networks often lacked multiple clusters or communities. Multiple clusters can be generated, however, if there are time windows
during development. Time windows ensure that regions of the network develop connections at different points in time. This
novel approach could generate small-world but not scale-free networks. The resulting topology depended critically on the overlap
of time windows as well as on the position of pioneer nodes. 相似文献
12.
G. Ghoshal M. E.J. Newman 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(2):175-184
We consider distributed networks, such as peer-to-peer networks, whose
structure can be manipulated by adjusting the rules by which vertices
enter and leave the network. We focus in particular on degree
distributions and show that, with some mild constraints, it is possible
by a suitable choice of rules to arrange for the network to have any
degree distribution we desire. We also describe a mechanism based on
biased random walks by which appropriate rules could be implemented in
practice. As an example application, we describe and simulate the
construction of a peer-to-peer network optimized to minimize search times
and bandwidth requirements. 相似文献
13.
Zhongzhi Zhang Shuigeng Zhou Tao Zou Lichao Chen Jihong Guan 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,60(2):259-264
We make a mapping from Sierpinski fractals to a new class
of networks, the incompatibility networks, which are scale-free,
small-world, disassortative, and maximal planar graphs. Some
relevant characteristics of the networks such as degree
distribution, clustering coefficient, average path length, and
degree correlations are computed analytically and found to be
peculiarly rich. The method of network representation can be applied
to some real-life systems making it possible to study the complexity
of real networked systems within the framework of complex network
theory. 相似文献
14.
K. P. Harikrishnan G. Ambika 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,61(3):343-353
We undertake a detailed numerical study of the twin phenomenon of stochastic
and vibrational resonance in a discrete model system in the presence of bichromatic
input signal. A two parameter cubic map is used as the model that
combines the features of both bistable and threshold systems. In addition to the
results already shown for continuous systems, our analysis brings out several
interesting features both for vibrational and stochastic resonance, including the
existence of a cross over behavior between the two. In the regime of vibrational
resonance, it is shown that the additional high frequency forcing can change the
effective value of the system parameter resulting in the shift of the bistable
window. In the case of stochastic resonance, the study reveals a fundamental
difference between the bistable and threshold mechanisms in the response, with
respect to multisignal input. 相似文献
15.
N. Gupte B. K. Singh 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):227-230
We study network traffic dynamics in a two dimensional communication
network
with regular nodes and hubs.
If the network experiences heavy message traffic, congestion occurs due
to finite
capacity of the nodes. We discuss strategies to manipulate hub
capacity and hub
connections to relieve congestion and define a coefficient of
betweenness centrality
(CBC), a direct measure of network traffic, which is useful for
identifying hubs which
are most likely to cause congestion. The addition of assortative
connections to hubs
of high CBC relieves congestion very efficiently.
An erratum to this article is available at . 相似文献
16.
C. P. Herrero 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,56(1):71-79
Kinetically-grown self-avoiding walks have been studied on Watts-Strogatz
small-world networks, rewired from a two-dimensional square lattice.
The maximum length L of this kind of walks is limited in regular lattices
by an attrition effect, which gives finite values for its mean value
〈L 〉. For random networks, this mean attrition length
〈L 〉 scales as a power of the network size,
and diverges in the thermodynamic limit (system size N ↦∞).
For small-world networks, we find a behavior that interpolates between
those corresponding to regular lattices and randon networks, for rewiring
probability p ranging from 0 to 1.
For p < 1, the mean self-intersection and attrition length of
kinetically-grown walks are finite.
For p = 1, 〈L 〉 grows with system size as N1/2,
diverging in the thermodynamic limit. In this limit and
close to p = 1, the mean attrition length diverges as (1-p)-4.
Results of approximate probabilistic calculations agree well with
those derived from numerical simulations. 相似文献
17.
Considering the heterogeneity of individuals’ influence in the real world, we introduce a preferential selection mechanism to evolutionary games (the Prisoner’s Dilemma Game and the Snowdrift Game) on scale-free networks and focus on the cooperative behavior of the system. In every step, each agent chooses an individual from all its neighbors with a probability proportional to kα indicating the influence of the neighbor, where k is the degree. Simulation results show that the cooperation level has a non-trivial dependence on α. To understand the effect of preferential selection mechanism on the evolution of the system, we investigate the time series of the cooperator frequency in detail. It is found that the cooperator frequency is greatly influenced by the initial strategy of hub nodes when α>0. This observation is confirmed by investigating the system behavior when some hub nodes’ strategies are fixed. 相似文献
18.
S. Carmi Z. Wu E. López S. Havlin H. Eugene Stanley 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(2):165-174
We study the transport properties of model networks such as
scale-free and Erd?s-Rényi networks as well as a real
network. We consider few possibilities for the trnasport problem.
We start by studying the conductance G between two arbitrarily
chosen nodes where each link has the same unit resistance. Our
theoretical analysis for scale-free networks predicts a broad
range of values of G, with a power-law tail distribution
$\Phi_{\rm SF}(G)\sim G^{-g_G}$
, where gG=2λ-1, and
λ is the decay exponent for the scale-free network degree
distribution. The power-law tail in ΦSF(G) leads to
large values of G, thereby significantly improving the transport
in scale-free networks, compared to Erd?s-Rényi networks
where the tail of the conductivity distribution decays
exponentially. We develop a simple physical picture of the
transport to account for the results. The other model for
transport is the max-flow model, where conductance is defined
as the number of link-independent paths between the two nodes, and
find that a similar picture holds. The effects of distance on the
value of conductance are considered for both models, and some
differences emerge. We then extend our study to the case of
multiple sources ans sinks, where the transport is defined between two
groups of nodes. We find a fundamental difference between
the two forms of flow when considering the quality of the
transport with respect to the number of sources, and find an
optimal number of sources, or users, for the max-flow case. A
qualitative (and partially quantitative) explanation is also
given. 相似文献
19.
G. Yan Z.-Q. Fu G. Chen 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(4):591-594
We study the SIS epidemic dynamics on scale-freeweighted networks with asymmetric infection, by both analysis andnumerical
simulations, with focus on the epidemic threshold aswell as critical behaviors. It is demonstrated that the asymmetryof infection
plays an important role: we could redistribute theasymmetry to balance the degree heterogeneity of the network andthen to
restore the epidemic threshold to a fnite value. On theother hand, we show that the absence of the epidemic threshold isnot
so bad as commented previously since the prevalence grows veryslowly in this case and one could only protect a few vertices
toprevent the diseases propagation. 相似文献
20.
D. Q. Li M. H. Li J. S. Wu Z. R. Di Y. Fan 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(4):423-428
In weighted networks, redistribution of link weights can
effectively change the properties of networks, even though the corresponding binary topology remains unchanged. In this paper,
the effects of weight randomization on synchronization of coupled chaotic maps is investigated on regular weighted networks.
The results reveal that synchronizability is enhanced by redistributing of link weights, i.e. coupled maps reach complete
synchronization with lower cost. Furthermore, we show numerically that the
heterogeneity of link weights could improve the complete synchronization on regular weighted networks. 相似文献