曲线正矢、负矢的计算
Calculations of Positive and Negative Vectors of Curve
根据批准的程序涂漆后，所有设备应以黑、白色丝网印刷于每个正矢方向和每列上。
All equipment shall be stenciled in black or white on each verses , column , equipment after painting as per approved procedure .
正矢