Cluster dynamics (CD) is a fast method for simulating long-term defect evolution in materials under irradiation. However, CD models based on mean-field rate theory do not account for spatial correlations between defects/clusters in cascades. Object kinetic Monte Carlo (OKMC) models take intrinsically account of defect spatial correlations, but they are limited by time scale and irradiation dose. A CD model with spatial correlation effect, termed as CD-SC, is developed based on a simple constant-time annealing method to determine CD source term by coupling Monte Carlo (IM3D) and OKMC (MMonCa) models. It shows that, results by CD-SC match those by full OKMC well. It is helpful for accuracy improvement of sequential multi-scale models of long-term radiation damage under typical irradiation conditions.

We developed and improved constitutive model, using LS-DYNA second development technology to embed a damaged Johnson-Cook constitutive model of commercial finite element software.Detailed description of structure of iterative algorithm and calculation process are presented. For experiments of perforation of 12 mm thick steel plates by 20 mm diameter projectiles with flat and conical noses, numerical simulations are carried out. Calculation and experiment results are consistent well. It indicates that constitutive algorithm, containing damage constitutive model and damage evolution equation are reasonable and reliable.

First-principles calculations are used to study alloy effects on configurations, stability and water adsorption of PtRu_n-1(n=2-14) and H₂O-PtRu_n-1 (n=2-14) systems. It shows that substitution energy of a Pt atom to a Ru atom is low which manifests that Pt is easy to form alloy with Ru clusters. Compared with pure Ru_n cluster, alloy effects enhance adsorption energy of H₂O molecule on PtRu_n cluster, and H₂O molecule is not easy to release in molecular form from PtRu_n cluster. Considering van de Waals force, adsorption energy of water on PtRu₇ increased and dissociation barrier decreased, making it possible to split water on PtRu₇. In conclusion, PtRu_n is suitable to be catalyst for spliting water and producing hydrogen.

For photoacoustic wave production of an ellipsoid particle,we derive analytical formula for wave profile on symmetrical axis.It shows that either for a prolate ellipsoid particle or for an oblate ellipsoid particle,wave profile deviates from typical N wave for a sphere particle.Moreover,deviated N wave is found containing characteristic information about shape and size of the particle.It promises a method for investigating shape as well as size of ellipsoid particles by measuring pulsed photoacoustic wave.

We present numerical simulation of Kevlar/Vinyl 3D orthogonal woven composite impacted by a spherical bullet with LS-Dyna software. Orthogonal constitutive equation with damage tensor and Hashin failure criteria are adopted for the Kevlar/Vinyl target. Time history of penetration velocity and loading of bullet show that steady penetration process and residual velocity agree well with experimental date. The damage modes basically reflect experimental results. Penetration process and damage modes are studied in details by analyzing damage evolution along the x fiber and interface matrix. It shows that the simulations are in good agreement with experiments.

Based on an Input-Output algorithm,a precise design method of DOE is proposed adapting fast Fourier transform algorithm.Numerical simulation indicates that this method improves beam shaping effectively.With same diffractive efficiency,interpolation iterative arithmetic reduces PV by 14% and RMS by 4%.The algorithm provides better initial phases of DOE for simulating annealing optimization than primitive Input-Output algorithm.

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.

We investigate non-s bound states in a screen Coulomb potential V(r)=-λ exp(-αr)/r,with different algorithms.The Schrödinger equation is solved using 4-step Runge-Kutta Method and Monte-Carlo approach.We analyzed errors of the MCH method.The energy spectrum and wave function in ground state and excited state agree well with those of 4-step Runge-Kutta method.

A fast simulation annealing (SA) algorithm for the design of diffractive optical elements (DOE) for uniform illumination is presented.The Tsallis statistic and corresponding utility function are introduced into a hybrid algorithm in which the self-iterative and SA algorithms are combined to enhance the efficiency.Compared with traditional SA algorithm,simulated results show that it saves 99% of time to converge the incident energy into a desired region with the same mean square error (MSE).

Magnetic feature of a two-dimension ferromagnetic/antiferromagnetic random diluted magnetic system is studied by micromagnetism and Monte Carlo method. The step effect of M-H magnetization curve is found in this system, and discussed with the one-dimension Ising model, which covers the energy of system and the spin configuration. It's found that the step effect can be produced in the antiferromagnetic coupling system with small number of spins.

The spin reorientation of magnetic thin film on a simple cubic lattice is simulated by employing Monte Carlo method.The influence of the magnetic anisotropy and the long-range dipolar interaction on the spin configurations of the system is also studied in detail.Meanwhile,the phase diagrams and the distributions of spin configuration,magnetization,specific heat of the systems are obtained.The results show that in a range of parameters,a transition from out-of-plane to in-plane ordering with the increase of the temperature is possible.

Numerical Hankel transform for circularly symmetric system at variable sampling intervals in input and optput planes is presented. An improved hybrid algorithm by using quasi Gradient Decent algorithm and spectrum selectivity is applied to the design of pure phase elements (PPE) in uniform illumination. Considering heat conductivity the simulated result shows that 97.2% of the incident beam energy is homogeneously concentrated into the desired focal spot in the target plane, and it fits to the required profile with the top profile error 1.1%.

Effects of SEU and SEB are simulated with 0.4μm diameter microbeam. SEU for drain region of MOSFET and CMOS SRAM are calculated. Collective charge depending on LET for specific device structure is calculated for different ions. LET and critical charge are provided. SEB for VDMOS is simulated and electric field, potential line, current, rate of impact ionization are given at different times along ion tracks. It is very important for heavy microbeam test physics models which have been set up.

A posteriori error estimates of residual type for generalized difference method (finite volume method) are derived for 2-D nonlinear parabolic equation on triangular meshes and an adaptive scheme suitable to problems with sharp moving fronts is designed.A data structure (not a tree structure) and a flexible local coarsening method for triangular meshes suitable to adaptive computations for evolution problems are also presented.

A hybrid method which collects the advantages of both iterative method and optimization method is introduced.This method is adopted in designing the diffractive optical device used in target illumination of ICF system,and better design results are obtained.The diffractive efficiency is up to 97.5%,the mean square error is 0.026 and the focal plane profile has an perfectly flat top.

A volume weighting CIC method is developed to compute the node charges and currents in PIC simulation of axial symmetrical plasmas.A set of formulae for computing the node charges and currents is derived.The results given here can be applied to 2(1/2) dimensional electrostatic and electromagnetic PIC simulation of axial symmetrical plasmas.

The constrained global optimization(CGO) algorithm is used to optimally design one demension diffrative optical element(DOE).The adopted CGO method is described in detail.The results are also given.

DV-X_α method,is applied for calculating the Electronic structure and Magnetic properties of YFe₁₂,which is an ideal structure of ThMn₁₂.The result shows that this method has satisfactory advantages on the theoretic of magnetic material.