有效值——XPath表达式。

Valid value - XPath expression.

有效值 ——从1开始的列位置。

Valid value - Column position starting from one.

再通过其均方计算出电压有效值。

The voltage effective value was figured out by mean square.

数据模型将定义对象结构、布局和有效值。

The data model will define the object structure plus layout and valid values.