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121.
A continuum opinion dynamic model is presented based on two rules. The first one considers the mobilities of the individuals, the second one supposes that the individuals update their opinions independently. The results of the model indicate that the bounded confidence εc, separating consensus and incoherent states, of a scale-free network is much smaller than the one of a lattice. If the system can reach the consensus state, the sum of all individuals' opinion change Oc(t) quickly decreases in an exponential form, while if it reaches the incoherent state finally, Oc(t) decreases slowly and has the punctuated equilibrium characteristic. 相似文献
122.
We discuss the evolution of the state and the average energy of the Fermi Ulam model in the case of periodic perturbation. By a perturbation technique, the time-dependent Sehr6dinger equation is solved and it is found that the particle will continuously absorb or radiate energy Jf the frequency of the oscillating wall meets the resonance condition. Usually, these two states cannot exist together at a certain frequency. However, there is an exception if the frequency is at some special values. We find these values and reveal that the energy for transmission has the minimum equivalent unit, which is in the form of a harmonic oscillator. 相似文献
123.
We simply use the relation between the asymptotic iteration method and the Nikiforov-Uvarov method for the analytical solution of the second order linear ordinary differential equations. We apply this relation to study the Schroedinger equation with potentials admitting quasinormal modes. Non-Hermitian PT symmetric potentials have also been studied. Energy eigenvalues in all the cases by the relation are found to be consistent with exact results. 相似文献
124.
P.D. Shidling N. Madhavan V.S. Ramamurthy S. Nath N.M. Badiger Santanu Pal A.K. Sinha A. Jhingan S. Muralithar P. Sugathan S. Kailas B.R. Behera R. Singh K.M. Varier M.C. Radhakrishna 《Physics letters. [Part B]》2008
Evaporation residue (ER) cross sections and gamma multiplicity distributions have been measured for 16O + 184W and 19F + 181Ta systems in the excitation energy range of 50–90 MeV, leading to the same compound nucleus 200Pb∗. Comparison of experimental results of both the systems shows that ER cross sections and moments of gamma multiplicity distribution of 16O + 184W system are significantly higher than those of 19F + 181Ta system at higher excitation energies. Present measurements directly shows the experimental signature of entrance channel effect even with the systems which are not very different with respect to their entrance channel mass asymmetry. It is further demonstrated that the reduction in the ER cross section and moments of spin distribution for 19F + 181Ta system is mainly due to the suppression of fusion of higher l values. 相似文献
125.
Sudhir R. Jain 《Physics letters. A》2008,372(12):1978-1981
We present the exact solution for the Schrödinger equation for a particle inside an N-dimensional regular simplex shaped enclosure. This result extends and unifies the earlier results for equilateral triangle and K-tetrahedron billiards. 相似文献
126.
By using the supersymmetric WKB approximation approach and the functional analysis method, we solve approximately the Dirac equation with the Eckart potential for the arbitrary spin-orbit quantum number κ. The bound state energy eigenvalues and the associated two-component spinors of the Dirac particles are obtained approximately. 相似文献
127.
We study the evolutionary Prisoner's dilemma game on scale-free networks, focusing on the influence of different initial distributions for cooperators and defectors on the evolution of cooperation. To address this issue, we consider three types of initial distributions for defectors: uniform distribution at random, occupying the most connected nodes, and occupying the lowest-degree nodes, respectively. It is shown that initial configurations for defectors can crucially influence the cooperation level and the evolution speed of cooperation. Interestingly, the situation where defectors initially occupy the lowest-degree vertices can exhibit the most robust cooperation, compared with two other distributions. That is, the cooperation level is least affected by the initial percentage of defectors. Moreover, in this situation, the whole system evolves fastest to the prevalent cooperation. Besides, we obtain the critical values of initial frequency of defectors above which the extinction of cooperators occurs for the respective initial distributions. Our results might be helpful in explaining the maintenance of high cooperation in scale-free networks. 相似文献
128.
Yuying Gu 《Physics letters. A》2008,372(25):4564-4568
A new type network growth rule which comprises node addition with the concept of local-world connectivity and node deleting is studied. A series of theoretical analysis and numerical simulation to the LWD network are conducted in this Letter. Firstly, the degree distribution p(k) of this network changes no longer pure scale free but truncates by an exponential tail and the truncation in p(k) increases as pa decreases. Secondly, the connectivity is tighter, as the local-world size M increases. Thirdly, the average path length L increases and the clustering coefficient 〈C〉 decreases as generally node deleting increases. Finally, 〈C〉 trends up when the local-world size M increases, so as to kmax. Hence, the expanding local-world can compensate the infection of the node deleting. 相似文献
129.
D.A. Kulikov 《Physics letters. A》2008,372(48):7105-7108
The solvable quantum mechanical model for the relativistic two-body system composed of spin-1/2 and spin-0 particles is constructed. The model includes the oscillator-type interaction through a combination of Lorentz-vector and Lorentz-tensor potentials. The analytical expressions for the wave functions and the order of the energy levels are discussed. 相似文献
130.
We investigate the spreading processes of epidemic diseases among many residential sites for different disease characteristics and different population distributions by constructing and solving a set of integrodifferential equations for the evolutions of position-dependent infected and infective rates, taking into account the infection processes both within a single site and among different sites. In a spreading process the states of an individual include susceptible (S), incubative (I), active (A) and recovered (R) states. Although the transition from S to I mainly depends on the active rate, the susceptible rate and the connectivity among individuals, the transitions from I to A and from A to R are determined by intrinsic characteristics of disease development in individuals. We adopt incubation and infection periods to describe the intrinsic features of the disease. By numerically solving the equations we find that the asymptotic behavior of the spreading crucially depends on the infection period and the population under affection of an active individual. Other factors, such as the structure of network and the popular distribution, play less important roles. The study may provide useful information for analyzing the key parameters affecting the dynamics and the asymptotic behavior. 相似文献