Abstract: A method for evaluating energy efficiency of electric arc furnace steelmaking comprises: obtaining original smelting information of the electric arc furnace; processing the original smelting information, and calculating an electrical energy efficiency evaluation index and a chemical energy efficiency evaluation index for process operation; wherein the electrical energy efficiency evaluation index comprises circuit efficiency, transformer tap capacity utilization rate and electrical energy thermal efficiency, and the chemical energy efficiency evaluation index comprises oxygen utilization rate, carbon powder utilization rate and chemical energy thermal efficiency; and evaluating an energy utilization condition of the electric arc furnace comprehensively based on the electrical energy efficiency evaluation index and the chemical energy efficiency evaluation index.

Abstract: A soil landslide matrix suction testing method and system based on soil body conductivity.

Abstract: Directional couplers for front end modules (FEMs) are disclosed that include a first port configured to receive a radio-frequency (RF) signal, a second port connected to the first port via a first transmission line and configured to provide an RF output signal, a third port connected to a second transmission line, the second transmission line being electromagnetically coupled to the first transmission line, and a fourth port connected to the second transmission line. The directional couplers further include an adaptive complex termination circuit connected to the fourth port and configured to provide an adaptive complex termination impedance selected to optimize combined performance of the directional couplers over multiple frequency bands.

Abstract: Directional couplers for front end modules (FEMs) are disclosed that include a first port configured to receive a radio-frequency (RF) signal, a second port connected to the first port via a first transmission line and configured to provide an RF output signal, a third port connected to a second transmission line, the second transmission line being electromagnetically coupled to the first transmission line, and a fourth port connected to the second transmission line. The directional couplers further include an adaptive complex termination circuit connected to the fourth port and configured to provide an adaptive complex termination impedance selected to optimize combined performance of the directional couplers over multiple frequency bands.

Abstract: Directional couplers for front end modules (FEMs) are disclosed that include a first port configured to receive a radio-frequency (RF) signal, a second port connected to the first port via a first transmission line and configured to provide an RF output signal, and a third port connected to a second transmission line, the second transmission line coupled to the first transmission line. A directional coupler in accordance with the present disclosure may further include a termination circuit connected to the second transmission line and configured to provide a first impedance when the RF signal is within a first frequency band and provide a second impedance when the RF signal is within a second frequency band.