The sensor virus is a serious threat,as an attacker can simply send a single packet to compromise the entire sensor network.Epidemics become drastic with link additions among sensors when the small world phenomena occ...The sensor virus is a serious threat,as an attacker can simply send a single packet to compromise the entire sensor network.Epidemics become drastic with link additions among sensors when the small world phenomena occur.Two immunization strategies,uniform immunization and temporary immunization,are conducted on small worlds of tree-based wireless sensor networks to combat the sensor viruses.With the former strategy,the infection extends exponentially,although the immunization effectively reduces the contagion speed.With the latter strategy,recurrent contagion oscillations occur in the small world when the spatial-temporal dynamics of the epidemic are considered.The oscillations come from the small-world structure and the temporary immunization.Mathematical analyses on the small world of the Cayley tree are presented to reveal the epidemic dynamics with the two immunization strategies.展开更多
We present a multifractal detrended fluctuation analysis （MFDFA） of the time series of return generated by our recently-proposed Ising financial market model with underlying small world topology. The result of the M...We present a multifractal detrended fluctuation analysis （MFDFA） of the time series of return generated by our recently-proposed Ising financial market model with underlying small world topology. The result of the MFDFA shows that there exists obvious multifractal scaling behavior in produced time series. We compare the MFDFA results for original time series with those for shuffled series, and find that its multifractal nature is due to two factors： broadness of probability density function of the series and different correlations in small- and large-scale fluctuations. This may provide new insight to the problem of the origin of multifractality in financial time series.展开更多
Tree topologies, which construct spatial graphs with large characteristic path lengths and small clustering coefficients, are ubiquitous in deployments of wireless sensor networks. Small worlds are investigated in tre...Tree topologies, which construct spatial graphs with large characteristic path lengths and small clustering coefficients, are ubiquitous in deployments of wireless sensor networks. Small worlds are investigated in tree-based networks. Due to link ad- ditions, characteristic path lengths reduce rapidly and clustering coefficients increase greatly. A tree abstract, Cayley tree, is con- sidered for the study of the navigation algorithm, which runs auto- matically in the small worlds of tree-based networks. In the further study, epidemics in the small worlds of tree-based wireless sen- sor networks on the large scale are studied, and the percolation threshold is calculated, at which the outbreak of the epidemic takes place. Compared with Cayley tree, there is a smaller percolation threshold suffering from the epidemic.展开更多
By considering energy-efficient anycast routing in wireless sensor network （WSN）, and combining small world characteristics of WSN with the properties of the ant algorithm, a power-aware anycast routing algorithm （...By considering energy-efficient anycast routing in wireless sensor network （WSN）, and combining small world characteristics of WSN with the properties of the ant algorithm, a power-aware anycast routing algorithm （SWPAR） with multi-sink nodes is pro- posed and evaluated. By SWPAR, the optimal sink node is found and the problem of routing path is effectively solved. Simulation results show that compared with the sink-based anycast routing protocol （SARP） and the hierarchy-based anyeast routing protocol （HARP）, the proposed algorithm improves network lifetime and reduces power consumption.展开更多
A modified Olami Feder-Christensen model of self-organized criticality on a square lattice with the properties of small world networks has been studied.We find that our model displays power-law behavior and the expone...A modified Olami Feder-Christensen model of self-organized criticality on a square lattice with the properties of small world networks has been studied.We find that our model displays power-law behavior and the exponent τ of the model depends on φ,the density of long-range connections in our network.展开更多
A lattice model for a set of pulse-coupled integrate-and-fire neurons with small world structure is introduced.We find that our model displays the power-law behavior accompanied with the large-scale synchronized activ...A lattice model for a set of pulse-coupled integrate-and-fire neurons with small world structure is introduced.We find that our model displays the power-law behavior accompanied with the large-scale synchronized activities among the units. And the different connectivity topologies lead to different behaviors in models of integrate-and-fire neurons.展开更多
Recently some P2P systems have constructed the small world network using the small world model so as to improve the routing performance.In this paper,we propose a novel probabilistic cache scheme to construct the smal...Recently some P2P systems have constructed the small world network using the small world model so as to improve the routing performance.In this paper,we propose a novel probabilistic cache scheme to construct the small world network based on the small world model and use it to improve CAN,that is,PCCAN(Probabilistic Cache-based CAN).PCCAN caches the long contact.It uses the worm routing replacing mechanism and probabilistic replacing strategy on the cache.The probabilistic cache scheme proves to be an efficient approach to model the small world phenomenon.Experiments in both the static and the dynamic network show that PCCAN can converge to the steady state with the cache scheme,and the routing performance is significantly improved with additional low overheads in the network compared with CAN.展开更多
文摘The sensor virus is a serious threat,as an attacker can simply send a single packet to compromise the entire sensor network.Epidemics become drastic with link additions among sensors when the small world phenomena occur.Two immunization strategies,uniform immunization and temporary immunization,are conducted on small worlds of tree-based wireless sensor networks to combat the sensor viruses.With the former strategy,the infection extends exponentially,although the immunization effectively reduces the contagion speed.With the latter strategy,recurrent contagion oscillations occur in the small world when the spatial-temporal dynamics of the epidemic are considered.The oscillations come from the small-world structure and the temporary immunization.Mathematical analyses on the small world of the Cayley tree are presented to reveal the epidemic dynamics with the two immunization strategies.
基金Supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars of State Education Ministry
文摘We present a multifractal detrended fluctuation analysis （MFDFA） of the time series of return generated by our recently-proposed Ising financial market model with underlying small world topology. The result of the MFDFA shows that there exists obvious multifractal scaling behavior in produced time series. We compare the MFDFA results for original time series with those for shuffled series, and find that its multifractal nature is due to two factors： broadness of probability density function of the series and different correlations in small- and large-scale fluctuations. This may provide new insight to the problem of the origin of multifractality in financial time series.
基金supported by the National Natural Science Foundation of China (61104086) the National Defense Advanced Research Project of China (40405020401)
文摘Tree topologies, which construct spatial graphs with large characteristic path lengths and small clustering coefficients, are ubiquitous in deployments of wireless sensor networks. Small worlds are investigated in tree-based networks. Due to link ad- ditions, characteristic path lengths reduce rapidly and clustering coefficients increase greatly. A tree abstract, Cayley tree, is con- sidered for the study of the navigation algorithm, which runs auto- matically in the small worlds of tree-based networks. In the further study, epidemics in the small worlds of tree-based wireless sen- sor networks on the large scale are studied, and the percolation threshold is calculated, at which the outbreak of the epidemic takes place. Compared with Cayley tree, there is a smaller percolation threshold suffering from the epidemic.
基金The Grand Fundamental Advanced Research of Chinese National Defense (No.S0500A001)
文摘By considering energy-efficient anycast routing in wireless sensor network （WSN）, and combining small world characteristics of WSN with the properties of the ant algorithm, a power-aware anycast routing algorithm （SWPAR） with multi-sink nodes is pro- posed and evaluated. By SWPAR, the optimal sink node is found and the problem of routing path is effectively solved. Simulation results show that compared with the sink-based anycast routing protocol （SARP） and the hierarchy-based anyeast routing protocol （HARP）, the proposed algorithm improves network lifetime and reduces power consumption.
基金The project supported by the Key Projects of National Natural Science Foundation of China under Grant No. 70431002 and National Natural Science Foundation of China under Grant Nos. 70371068 and 10247005
基金The project supported by the Key Project5 of National Natural Science Foundation of China under Grant No 70431002, and National Natural Science Foundation of China under Grant Nos. 70371068 and 10247005
文摘基于我们以前建议了的所有节点的一样的度的模型，一个新算法，“在整个顶点的所谓的传播(SAV ) ”算法，从一枚常规戒指为 generatingsmall 世界性质被建议格子。在随机给连接换新电线期间， SAV 被用来保留连接的未改变的数字。把 SAV 算法与在整个边界的 Watts-Strogatzmodel 和“传播”作比较算法，三个方法能有小世界网络的一样的拓扑的性质。这些结果提供小世界网络的多样的形成。它对为在与网络联系的节点和交往的自动机内的相互的振荡器的动力学的一些应用的研究有用。
文摘A modified Olami Feder-Christensen model of self-organized criticality on a square lattice with the properties of small world networks has been studied.We find that our model displays power-law behavior and the exponent τ of the model depends on φ,the density of long-range connections in our network.
基金＊The project supported by National Natural Science Foundation of China under Grant No. 90203008 and the Doctoral Foundation of the Ministry of Education of China
文摘A lattice model for a set of pulse-coupled integrate-and-fire neurons with small world structure is introduced.We find that our model displays the power-law behavior accompanied with the large-scale synchronized activities among the units. And the different connectivity topologies lead to different behaviors in models of integrate-and-fire neurons.
基金Sponsored by the Science & Technology Committee of Shanghai Municipality Key Technologies R&D Project(Grant No.03dz15027)the Science & Technology Committee of Shanghai Municipality Key Project(Grant No.025115032).
文摘Recently some P2P systems have constructed the small world network using the small world model so as to improve the routing performance.In this paper,we propose a novel probabilistic cache scheme to construct the small world network based on the small world model and use it to improve CAN,that is,PCCAN(Probabilistic Cache-based CAN).PCCAN caches the long contact.It uses the worm routing replacing mechanism and probabilistic replacing strategy on the cache.The probabilistic cache scheme proves to be an efficient approach to model the small world phenomenon.Experiments in both the static and the dynamic network show that PCCAN can converge to the steady state with the cache scheme,and the routing performance is significantly improved with additional low overheads in the network compared with CAN.
