Research and Make for Power Transmitter of echo sounder测深仪发射板的研究与制作17、Abstract For multi beam swathResearch and Make for Power Transmitter of echo sounder测深仪发射板的研究与制作17、Abstract For multi beam swath
通过一托浅滩时，要一直测深校时水深及海面下多变的沙纹。
a representation of forms or objects on a surface by means of lines;"drawings of abstract formsa representation of forms or objects on a surface by means of lines;"drawings of abstract forms
\"he did complicated pen-and-ink drawings like medieval miniatures\"
Syntactics is a subject to study abstract formal connexion among the signs.Syntactics is a subject to study abstract formal connexion among the signs.
符号学是研究符号之间的抽象形式联系的学科。
