Abstract: The present disclosure discloses a rail vehicle. The rail vehicle includes: a plurality of bogies, where the bogie has a straddle recess suitable for straddling a rail; and a vehicle body, where the vehicle body is connected to the plurality of bogies and pulled by the plurality of bogies to travel along the rail, and the vehicle body includes a plurality of compartments hinged sequentially along a length direction of the rail; the plurality of compartments forms at least one compartment group, the compartment group includes three compartments hinged sequentially, and the bottom of each of only compartments that are located at two ends of the compartment group and that are of the three compartments is connected to the bogie; and in the length direction of the rail, a surface that is of a compartment at at least one end of the vehicle body and that faces away from an adjacent compartment is provided with an escape door that can be opened and closed.

Abstract: The present disclosure discloses a rail vehicle. The rail vehicle includes: a plurality of bogies, where the bogie has a straddle recess suitable for straddling a rail; and a vehicle body, where the vehicle body is connected to the plurality of bogies and pulled by the plurality of bogies to travel along the rail, and the vehicle body includes a plurality of compartments hinged sequentially along a length direction of the rail; the plurality of compartments forms at least one compartment group, the compartment group includes three compartments hinged sequentially, and the bottom of each of only compartments that are located at two ends of the compartment group and that are of the three compartments is connected to the bogie; and in the length direction of the rail, a surface that is of a compartment at at least one end of the vehicle body and that faces away from an adjacent compartment is provided with an escape door that can be opened and closed.

Abstract: A pre-amplifier comprises at least two PMOS transistors operated as source followers and two NMOS transistors operated as amplifiers, or, two NMOS transistors operated as source followers and two PMOS transistors operated as amplifiers to raise or reduce the voltage of input signals and at least four current sources with the same current value which can be adjusted according to the output load of the pre-amplifier. The MOS transistors have the same transconductance so that the minimum differential voltage can be attained. Since the differential signals change alternately, MOS transistors will switch among the three working status: cut-off, saturation and linear region. Because of the cut-off and linear region, the present invention can achieve the very low power consumption less than one third of the conventional one.

Abstract: A pre-amplifier comprises at least two PMOS transistors operated as source followers and two NMOS transistors operated as amplifiers, or, two NMOS transistors operated as source followers and two PMOS transistors operated as amplifiers to raise or reduce the voltage of input signals and at least four current sources with the same current value which can be adjusted according to the output load of the pre-amplifier. The MOS transistors have the same transconductance so that the minimum differential voltage can be attained. Since the differential signals change alternately, MOS transistors will switch among the three working status: cut-off, saturation and linear region. Because of the cut-off and linear region, the present invention can achieve the very low power consumption less than one third of the conventional one.