The physical properties of modified nano-SiO₂ and methyl-phenyl-dimethoxy-silane modified phenolic resin are studied by molecular dynamics simulation. The results show that the glass transition temperature of unmodified phenolic resin at 300 K is 362 K, the elastic modulus and shear modulus are 5.45 GPa and 2.19 GPa, the thermal conductivity and thermal expansion coefficients are 0.37 W·(m·k)^-1 and 3.8×10^-5K^-1, respectively. The addition of nano-SiO₂ increases the glass transition temperature by 1.6%, the elastic modulus and shear modulus by 34.9% and 28.8%, and the thermal conductivity and thermal expansion by 11% and 31.6%, respectively. The thermal conductivity and thermal expansion are reduced by 11% and 31.6%, respectively. SiO₂ surface grafting 3%, 5%, 7% and 10% silane coupling agent and methyl-phenyl- dimethoxy-silane modified phenolic resin, the glass transition temperature increased by 10.5%, 15.2%, 16.8%, 19.3% and 1.5% respectively, the elastic modulus increased by 44.4%, 53.2%, 53.8%, 63.5% and 13.4% respectively, and the thermal conductivity decreased by 12.4%, 13.5%, 11.2%, 7% and 10% respectively. Moreover, the thermal expansion coefficient of phenol formaldehyde resin modified by methyl phenyl dimethoxy silane increased by 51.8% compared with the unmodified phenol formaldehyde resin. The study show that the doping of nano-SiO₂, the grafting of silane coupling agent on the SiO₂ surface, and the modification of methyl-phenyl-dimethoxy-silane can improve the glass transition temperature, and mechanical properties and reduce the thermal conductivity of phenolic resin. Only nano-SiO₂ doping can reduce the thermal expansion coefficient, whereas the modification of methyl-phenyl-dimethoxy-silane will increase substantially.

Based on theory of fractal and assumption of continuity, a well test model for multiple fractured horizontal wells in fractal fractured shale gas reservoirs was established in which adsorption, desorption and cross flow between matrix and fractures are considered. Solution of the model was obtained with Laplace transform, point source solution and pressure drop superposition principles. Double logarithmic curves of dimensionless pressure changing over time were obtained. Characteristics of pressure of multiple fractured horizontal well in fractal fractured shale gas reservoirs and influence of parameters, such as fractal index and fractal dimension, on pressure and production curves were analyzed. It shows that the curves can be divided into 7 flow stages. Slope of unstable pressure well-test curves in the middle and late stages is greater with bigger fractal index or smaller fractal dimension.

Two-dimensional density distributions of dense plasmas in laser confinement fusion are revealed with proton imaging. Simultaneous iterative reconstruction algorithm (SIRT) is used to study influence factors of two-dimensional plasma density reconstruction. Effects of plasma density gradient, magnitude of density and initial proton energies on reconstruction errors are investigated. Importance of figuring out rough area and range of simulated plasma zone before simulation is analyzed. Furthermore, an analytical expression between reconstruction errors and noises is established through data analyses.

Acoustic streaming generated by standing waves between two-dimensional flat plates is analyzed based on multiple relaxation time lattice Boltzmann method (MRT-LBM). Simulation results are in good agreement with approximate analytical solutions of Rayleigh streaming. Effects of viscosity and width between two plates on acoustic streaming in standing waves are studied. Dimensionless velocity distributions of x component with different viscosity at x=L/4 and dimensionless velocity distributions of y component with different viscosity at x=L/2,and effects of widths on boundary layer vortex thickness and formation progress of acoustic streaming in standing waves are revealed. It demonstrates availability of MRT-LBM model in simulating acoustic streaming in standing waves.

For interaction behavior of users in online social networks,we build a biased diffusion model to explain time interval distribution characteristics of group posting and event by relating task interval time τ and task execution time θ. We demonstrate that, for τ≥θ,time intervals follow power law distribution; and for τ>>θ,time intervals follow power law distribution with exponential effect. Experimental results validate the model.

Density reconstruction of inhomogeneous dense DT plasmas is studied with simultaneous iterative reconstruction technique(SIRT).In simulation of density diagnostics of a two-dimensional(2D) slice plasma,fast protons used fordiagnostics can be generated with laser-plasma interaction and energy loss of fast protons going through plasmas is crucial.As original and final energies of protons are given,density reconstruction by SIRT method is done without noise level of final energies.Accuracy of the method is better than that of the Tikhonov regularization method based on deviation principle of L-curve.In addition,the SIRT method is available with incomplete data.

A method predicting crosstalk coupling between interconnecting wires with artificial neural networks is proposed.Parameters that influence crosstalk coupling are selected as input prediction factors.Back propagation neural network constructs a mapping relation between input prediction factors and output crosstalk coupling of interconnecting wires.Learning sample sets computed by MTL and FDTD method are used to train BP networks.A prediction BP model is obtained.BP predictions and test sample results are compared.