A finite element model of a three-dimensional composite laminate with initial damage is established with continuum damage mechanics.With strain failure criterion proposed by Linde and a parameter modifying damage function,failure behavior of matrix and fiber in laminates is simulated.Damage variable's variation with deformation can be achieved by changing of the parameter.Numerical results vary obviously with the parameter.Examples demonstrate that the parameter can reduce error,and make simulation agree with experiment result.The induced parameter can extend application of the Linde model and increase precision of simulation.

According to the principles of Modeling & Simulation(M&S)and charactersitic of detonation system that final performances are determined by initial conditions,total uncertainties are sorted to three parts that varying along with initial conditions.It reveals how uncertainties are brought on and evolve from benchmark models to new models.Based on engineering practices and technology of verification & validation,a framework of quantification about uncertainty is brought forward in detonation simulation.An example is presented to demonstrate general idea in quantifying uncertainty of M&S.

An improved time-delayed dual model for internet congestion control is investigated.Normal form theory,center manifold theorem and Hopf bifurcation theory are used for analysis.Bifurcation and stability analysis are mainly decided by communication time delay.As the delay passes through a critical value,Hopf bifurcation forms,which leads to a large oscillation of link price function.In addition,bifurcation direction and bifurcation periodic solution are derived,which provide model design with theoretical foundations.This work is summarized as two theorems verified by numerical simulations.

The full-core plus correlation method(FCPC)is extended to calculate the energies and fine structures of 1s²4p states for the lithium-like systems with nuclear charge from Z=11 to 20.The transition energies(2s²S_1/2-4p²P_1/2,3/2) and dipole oscillator strengths are also calculated.The non-relativistic energies and wave functions are calculated by the Rayleigh-Ritz method.Relativistic and mass-polarization effects on the energies are included as the first-order perturbation corrections.The quantum-electrodynamics contributions to the transition energies are estimated by using the effective nuclear charge.Our results are in agreement with the experimental data available in the literature.

According to the fundamental equation of steady current field, the corresponding functional equation is obtained by use of the linear differential operator. Since inversion image algorithm is very important in crosshole resistivity tomography, a improved Occam's inversion is presented. Image results of the theoretical model data and the field measured data are given and discussed.