Abstract: Device and methods for real-time polarization-dependent loss monitoring at coherent transceivers. In one embodiment, there is provided a method of monitoring a polarization dependent loss (PDL) of a signal during transmission through an optical communication link, the method comprising: receiving the signal by a coherent receiver, the received signal being subjected to one or more impairments in Amplifier Gain Control (AGC) mode, the one or more impairments including PDL; estimating an AGC gain effect of the AGC mode; compensating for the AGC gain effect in the received signal; determining the PDL from the compensated signal; and reporting the PDL.

Abstract: A two-stage high-pressure pump includes a reduction gearbox disposed in front of a motor, a-crank shaft connected to an output shaft of the reduction gearbox, a connecting rod having one side connected to the crank shaft and the other side connected to a primary piston, a primary one-way valve disposed at one end of the primary piston, and a gas storage chamber provided at the middle of the primary piston. The other end of the primary piston is connected to a secondary piston rod in a highly sealed manner. The secondary piston rod is provided with a vent in the middle, and the other end of the secondary piston is connected to a high-pressure piston. A secondary one-way valve is disposed in the secondary high-pressure piston. A noise attenuating filter and a one-way valve block are disposed at an air inlet of the primary cylinder cover.

Abstract: A back adjustable electrical bed frame comprises a head panel, a back panel, a buttocks panel, a thigh panel, a shank panel, a back pusher motor and a leg pusher motor. The leg pusher motor drives the buttocks panel through a scissor support assembly. The shank panel, parallel to the base, moves back and forth. The back panel has a back panel pivot at a quarter to a half of its lower part. The back panel is fixed to the base by a column having one end fixed to the base and the other end connected to the back panel pivot. The back pusher motor has a front end pivot connected with the back panel and a rear end pivot fixedly connected with the base. The front end pivot, the rear end pivot and the back panel pivot form a triangle to position an angle of the back panel.

Abstract: A two-stage high-pressure pump includes a reduction gearbox disposed in front of a motor, a-crank shaft connected to an output shaft of the reduction gearbox, a connecting rod having one side connected to the crank shaft and the other side connected to a primary piston, a primary one-way valve disposed at one end of the primary piston, and a gas storage chamber provided at the middle of the primary piston. The other end of the primary piston is connected to a secondary piston rod in a highly sealed manner. The secondary piston rod is provided with a vent in the middle, and the other end of the secondary piston is connected to a high-pressure piston. A secondary one-way valve is disposed in the secondary high-pressure piston. A noise attenuating filter and a one-way valve block are disposed at an air inlet of the primary cylinder cover.

Abstract: The invention discloses a back adjustable electrical bed frame, comprising a head panel, a back panel, a buttocks panel, a thigh panel and a shank panel, a back pusher motor and a leg pusher motor are configured below the back panel, the leg pusher motor drives the buttocks panel through a scissor support assembly, the shank panel moves back and forth and parallel to the base, a back panel pivot is configured at a quarter to a half of the lower part of the back panel, the back panel is fixed to the base by means of a column, one end of the column is fixed to the base and the other end of the column is connected to the back panel pivot, the front end pivot of the back pusher motor is connected with the back panel, and the rear end pivot is fixedly connected with the base; the front end pivot of the back pusher motor, the rear end pivot of the back pusher motor and the back panel pivot form a triangle to position the angle of the back panel.

Abstract: An adjustable mattress comprises a foldable bed frame, a decorative soft package covering the bed frame, and a plurality of independent barrel springs inside the bed frame. The plurality of independent barrel springs are arranged in a matrix. The bed frame and the independent barrel springs are covered with a cover cloth and an upper sealing mattress. The bed frame includes two transverse frames and two vertical frames, which are connected via bendable joints. The two transverse frames comprise two PVC sections connected by folding joints, and the two vertical frames comprises a plurality of PVC sections connected by bidirectional bending joints.

Abstract: A high-pressure pump includes a pump cover, an air cylinder, a piston, a water cooling device, and a pump seat. The air cylinder is formed by a first air cylinder, a second air cylinder and a third air cylinder whose diameters are progressively reduced and that are coaxially disposed. The piston is also formed by a first piston, a second piston and a third piston whose diameters are progressively reduced and that are respectively disposed in the first air cylinder, the second air cylinder and the third air cylinder. A water cooling device is disposed between the second air cylinder and the third air cylinder.

Abstract: The present invention relates to a high-pressure pump, and belongs to the manufacturing field of high-pressure pumps. A high-pressure pump includes a pump cover, an air cylinder, a piston, a water cooling device, and a pump seat. The air cylinder is formed by a first air cylinder, a second air cylinder and a third air cylinder whose diameters are progressively reduced and that are coaxially disposed. The piston is also formed by a first piston, a second piston and a third piston whose diameters are progressively reduced and that are respectively disposed in the first air cylinder, the second air cylinder and the third air cylinder.

Abstract: A 9V rechargeable battery comprising a plurality of column cells connected in series and enclosed by a container and a cover with a negative terminal and a positive terminal. Said container (1) further comprises a pair of lateral sidewalls formed with openings and another pair of lateral sidewalls formed with recesses so as to receive said cells snugly.

Abstract: A 9V rechargeable battery comprising a plurality of column cells connected in series and enclosed by a container and a cover with a negative terminal and a positive terminal. Said container (1) further comprises a pair of lateral sidewalls formed with openings and another pair of lateral sidewalls formed with recesses so as to receive said cells snugly.