It is a partial differential equation satisfied by the electric field e.
这是一个，由电场e确定的偏微分方程。
2
The equations are extra nonlinear differential equations. the dexter function is not continuous in field of real number .
该方程右边的函数在实数域内不连续，是一个高度非线性微分方程组。
3
HART field-bus protocol is used in output of system pressure or differential pressure transmitter, digital signals is transmitted with MODBUS via RS485.