A deterministic algorithm is developed to implement a physical-based gas-surface interaction model. The key of the algorithm is to calculate discretized matrix by a deterministic way, which represents the scattering kernel of single gas-surface collision and governs the gas molecular velocity distribution function.By considering the attractive potential well and successive gas-surface collisions, this algorithm describes physically the variation of gas molecular velocity distribution functions at the interface.Comparing with existing stochastic implementation algorithm based on Monte Carlo sampling, this deterministic implementation algorithm calculates accurately and efficiently the relation between incident and reflected velocity distributions of gas molecules. Therefore, it provides a better boundary condition for the deterministic simulation methods of rarefied gas flows based on discretized velocity space.

A straight-line track model is developed, and validity of Kalman filter track reconstruction algorithm with the track model was verified in detail. It shows that given sufficient hits track parameters converge to true values. The track reconstruction program is implemented in MarlinTPC reconstruction framework in practice. By choosing track reeonstruction parameters reasonably, the program discriminates noise efficiently and reconstructs tracks. The algorithm is valuable in track reconstruction of large prototypes.

With electric potential of three electrodes, discrete equations of surface electric charge density was founded with boundary element integral equations. The distribution of surface electric charge on the electrodes was calculated by solving a linear equation group. Then the spatial distribution of the potential and the electric field are obtained. In vacuum, the edge effect of a double glow discharge was analysed.