Method of completing square is often used when transforming a quadratic form into a normal one, whose process is equivalent to making the relevant matrix contract diagonal.
Researches show that the equivalent load method couldn't be used to calculate the prestressing action in the combination form, but the method of restraining secondary moments should be used.
研究表明，这种组合线形不能按等效荷载法来计算预应力的作用，而应采用约束次弯矩法来计算。
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The main point of the method proposed in this paper is that the form of the transfer function of the equivalent feedback compensation is specified at the outset.