Using Mathematica symbalic manipulation system, the computer program MATHELDCA is developed for calculating one loop Feynman diagrams in renormalizable gauge theories. It is only needed to input the amplitudes of contributed diagrams according to the Feynman rule, so as to calculate the radiative corrections of particle process.

A computer program Gamma, which is based on the computer symbolic algebra manipulation system mathematica, is introduced. This program has defined γ matrix expressions and their calculations. It is very convenient to calculate Feynman diagrams using this program.

By defining vaccum self-energy diagrams and using REDUCE programming langauge, the calculation of renormalization constans in the weinberg-salam standard model can be performed by computer.

This paper presents a numerical study of the electric field distortion near the side frame of Proportional Inclined Ghanber (PIC) ,which is made of G10 epoxy resin plate, by using the finite element method. The calculation results are quite consistent with experimental tests. An optimized design scheme for improving the gain efficiency uniformity of the anode signal wires near the side frame is proposed.