If the orientations of driving elements are reversed then it is necessary to change a sign in their terminal relations . 如果驱动元素的定向取反了，就必须在它们的端子关系中改变符号。
2.
An element is lumped if its terminal relation is an ordinary differential equation as opposed to a partial differential equation . 如果一个元素的端子关系是一个常微分方程，其反面为一个偏微方程，则它是集总的。
