二阶(半)线性差分方程的 定性理论问题一直受到广大学者和专家的关注，尤其振动性问题更是吸引着国内 外许多著名学者的注意力-The qualitative theory of seeond order linear(semilinear)difference equations is an issue that has been paid close attention to at home and abroad academic ckcles all along，especial