In social networks, the age and the region of individuals are the two most important factors in modeling infectious diseases. In this paper, a spatial susceptible-infected-susceptible (SIS) model is proposed to describe epidemic spreading over a network with region and age by establishing several partial differential equations. Numerical simulations are performed, and the simulation of the proposed model agrees well with real influenza-like illness (ILI) in the USA reported by the Centers for Disease Control (CDC). Moreover, the proposed model can be used to predict the infected density of individuals. The results show that our model can be used as a tool to analyze influenza cases in the real world.

The shock Hugoniot relationship of concrete was studied based on concrete test subjected to the high-velocity impacting loading by one stage gas gun. The P-U(pressure-partical speed) shock Hugoniot relationship curve of concrete was gained from the D-U(shocking wave speed-partical speed) curve of concrete, and the equation of volume pressure P and volume strain v was put forward according to the example analysis. Moreover, based on the polynomial Grьneisen equation, the parameters of high-pressure equation of state of concrete were got by fitting the test date, and the theoretical values from the equation matched well with the experimental ones.

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Shock initiation experiments on the explosives pressed TNT was performed to obtain in-situ pressure/radial displacement gauge data for the purpose of determining the Ignition and Growth reaction flow model with proper modeling parameters. The pressure and radial displacement were got by manganin-constantan composite 2-D Lagrange sensor. The particle velocity, relative volume, internal energy and fraction reacted of shock initiation process has been calculated by 2-D Lagrangian analysis method.

A multi-degree-of-freedom (MDOF) vibration isolation system (VIS) model is established with finite element method. And the numerical simulation results of the model under axisymmetric load in a good fit to the simplified model results. The model dynamics behavior under any load also was calculated, and it makes a further analysis for the vibration isolation effect of the model.