| 2. | It is the significant innovation of this paper . most of the blueprints are painted by manual workers . moreover , due to the diversity of the electric component symbol , different criterion arouses the inconvenience of the blueprints re - using 纸质电路图纸大部分由人工手绘,而且由于电路元器件自身的多样性和不同地区采用的标准的多样性,图纸使用符号的标准不同,这就造成了图纸复用的不便。 |