In this paper an algorithm of complete decoding procedure for the Goppa codes with generator polynomial G(z)=z²+z+β and parameters (2^m, 2^m-2m, 5) is shown. The algorithm requires at most m times calculatng inner product of vectors over GF(2) and finding roots of quadratic equation in GF(2^m). Por m ≤12, the algorithm has been realized.

In this paper, a unified approach of iterative methods, such as Jacobi method, Gauss-Seidel method, SOR method, etc., for solving linear equations is discussed and studied. For the reason stated in this paper, this approach is called 2-dimensional iterative method. The convergence and the rate of convergence of iteration process are improved by using this new approach. The theoretical analysis and the computing results demonstrate that this approach has many advantages over the generally used iterative methods. it is useful in solving the large scale electric circuits, such as VLSI.

In this paper, the concept of the primary subgraph of a composite graph associated with a linear active network is introduced, and a new topological method, called the primary subgraph method, for linear active network analysis is presented. This method is the reform and unification of the complete tree method and directed tree method. It has solved the sign evaluation problem and eancellation term problem. Its sign evaluation is far simpler than the complete tree method. It is superior to the directed tree method since it has no cancellation terms.

The orbits of an electron in self-fields, linear wiggler and axial fields are calculated. Then the spontaneous emission coefficient and the growth rate of the stimulated scattering are obtained. The numerical results show that under some conditions the selffields can enhance the radiation.

In the numerical analysis of axially symmetry electromagnetic field, the finite element method using ring unit with rectangular cross -section has more advantages than other methods. The ring unit characteristic equations in relation to Laplace s, Poissou s and Helmholtz s equa.tions are derived. Using this method, the field structure of cylindrical capacitor and the capacitance and quality factor of the end of laded eoaxial cavity are successfully analyzed.

In this paper, formulas of third geometrical deflection aberratios for an ideal uniform electrostatic field are deritved by solving the motion equations of an electron passing through this field. The results can be used not only to estimate the distortion, astigamatism and field curvature, and coma produced by a Gaussian or shaped electron beam, but also to set the original size of the deflector and determine the effect caused by the misaligument between the electron beam and the deflector. Some mistakes in Sturrock's paper (1955) are also poited out.

Starting from the dispersion relationship of gyro magnetron, the expression of small-signal gain has been derived. The electronic efficiency is also estimated. The computing results show tha.t under defined conditions a gain per unit length of 2dB/cm and an electronic efficiency of nearly 8% a.t 35 GHz with 6th harmonie of the cyclotron frequency can be obtained. The computing results will be an useful information for design and improvement of gyro-magnetron. Moreover, the conceived gyro-peniotron with magnetron waveguide is proposed for efficiency enhancement.

In this paper, relationship between the Q value and the resonant frequency is derived by means of equivalent circuit method. The parameters are obtained by taking the cavity cylinder as a helical circuit. A series of curves for optimum design is plotted.In our experiment, a high Q value of 900 to 1000 in the frequency range of 1 to 1.4 GHz is easily obtained, the resonator has the merits of small dimension, wide frequency range and simplicity in construction.

A method for caleulating the phase shift of a dielectric slab loaded circular waveguide with small ellipticity is described. It gives an excellent result for engineerring purposes, although it is not rigorous in theory. The maximum difference between the calculated and measured results for a 90° phase shift is only 1.4°in 500 MHz band-width at 4GHz.

The boundary element method of potential theory is described in this paper. It is used to analyze the characteristic impedance of TEM transmission line with arbtrary cross-seetions. It is shown that the boundary element method has some advantages, such as the number of nodes required for this method is less than that for the finite element method, and the accuracy of this method is higher than that of the moment method.

In this paper, the photoemissions of Pd-Ag-O-Cs and Sb-Na-K-Cs photocathodes under the illumination of clear star radiation are ealculated and compared. From the calcula.ted results, it gives a fine pospect that the Pd-Ag-O-Cs photocathode may be used in low light level night vision.