Abstract: Disclosed is a method, system, and electronic device for precision roll bending of cylinder with variable curvature section. The method first obtains process parameters of roll bending of a target cylinder, and then conducts roll bending rebound simulation of the cylinder based on the process parameters to determine influence factors of rebound compensation error. Then, multiple sets of different preset influence factor values are set to perform roll bending rebound simulation of different arc segments. This disclosure uses multiple simulations of the rebound caused by cylinder roll bending to determine the factors that affect the rebound compensation error and the magnitude of the rebound compensation error that may be caused by these factors. Finally, an expression for the rebound compensation error is obtained to correct the rebound compensation equation, eliminating the error caused by rebound compensation, and ensuring that the cylinder forming meets the expected accuracy requirements.

Abstract: The invention relates to a device for testing the precision retaining ability and fatigue life of RV reducer. The device includes a workbench, a mounting bracket base, a upper pressure plate for the mounting bracket, a servo motor, a mounting fixed sleeve, a tested RV reducer, a temperature sensor, an extension arm, a simulated swing arm, two counterweight blocks named the first and second counterweight block, the first displacement sensor, a sensor holder, a sensor protector, a detection rod, and the second displacement sensor. The device is equipped with two counterweight blocks at the end of the simulated swing arm to simultaneously provide variable loaded torque and loaded bending moment to the RV reducer. The first displacement sensor is placed under the counterweight block to measure the positioning accuracy and repeat positioning accuracy of RV reducer. The second displacement sensor is placed under the detection rod to measure the bending stiffness of RV reducer.

Abstract: The invention relates to a device for testing the precision retaining ability and fatigue life of RV reducer. The device includes a workbench, a mounting bracket base, a upper pressure plate for the mounting bracket, a servo motor, a mounting fixed sleeve, a tested RV reducer, a temperature sensor, an extension arm, a simulated swing arm, two counterweight blocks named the first and second counterweight block, the first displacement sensor, a sensor holder, a sensor protector, a detection rod, and the second displacement sensor. The device is equipped with two counterweight blocks at the end of the simulated swing arm to simultaneously provide variable loaded torque and loaded bending moment to the RV reducer. The first displacement sensor is placed under the counterweight block to measure the positioning accuracy and repeat positioning accuracy of RV reducer. The second displacement sensor is placed under the detection rod to measure the bending stiffness of RV reducer.

Abstract: Disclosed is a method for synthesizing dihydroxyl-terminated polyphenylene oxide oligomer. The method for synthesizing dihydroxyl-terminated polyphenylene oxide oligomer, comprising oxidatively copolymerizing monohydric phenol and dihydric phenol in the presence of a metal-polyethyleneimine complex as a catalyst, to obtain the dihydroxyl-terminated polyphenylene oxide oligomer. The synthesizing method of the present disclosure uses a metal-polyethyleneimine complex as a catalyst, which has a milder catalytic activity, can effectively promote the reaction between the dihydric phenol and the monohydric phenol, increases the hydroxyl content of the product, meanwhile reduces the amount of the residual dihydric phenol monomer in the product, so that the quality of the product can be improved.

Abstract: The present invention discloses a method and an apparatus for data disaster tolerance preprocessing and a Service Control Point (SCP), the method and the apparatus are used in each SCP of a plurality of SCPs with databases, the method comprises: setting a first database in a first SCP, wherein the first database is used to perform disaster tolerance backup for a second database in a second SCP. Through the present invention, the cost of the construction of the system is reduced, and the stability and feasibility of a disaster tolerance system are enhanced.

Abstract: The present invention discloses a method and an apparatus for data disaster tolerance preprocessing and a Service Control Point (SCP), the method and the apparatus are used in each SCP of a plurality of SCPs with databases, the method comprises: setting a first database in a first SCP, wherein the first database is used to perform disaster tolerance backup for a second database in a second SCP. Through the present invention, the cost of the construction of the system is reduced, and the stability and feasibility of a disaster tolerance system are enhanced.