Applied Mechanics and Materials Vol. 150

Abstract: The artificial intelligence technology has been widely used in fault diagnosis, but under the unusual circumstances, if the real time data is lacking, it is difficult to build new mathematical model. Now the artificial intelligence technology has been used in the fault diagnosis field. The CNC hinders diagnosis using neural network is introduced in this paper, and the fault diagnosis method of numerical control machine is analyzed, and hence the CNC fault diagnoses are realized by RBF neural network algorithm and program.

Abstract: Active Magnetic Bearing (AMB), which supports freely a rotor by using controllable electromagnetic force, have a lot of advantages such as adjustable stiffness and damp that the traditional bearings can’t compare with. Power Amplifier is an important part of AMB Control System. It can magnify or convert the control signal which can’t drive the electromagnetic iron actuators directly into a power signal. Hence, the performance of power amplifier plays a crucial role in the technique capability of control system. A design method of the PWM Power Amplifier was introduced through the research of the power Amplifier, and hence the CNC fault diagnoses are realized by RBF neural network algorithm and program.

Abstract: Gyroscopic effects in the flywheel rotor greatly influence rotor stability especially at high speed. When the pole-zero position moves to right of s-plane, the damping of the pole is getting smaller, and the stability of system is getting worse with the increasing of rotor speed when the decentralized PD control law is used only. The LQR (linear quadratic regulator) control method is used to reduce gyroscopic effect and forced vibration. The simulation results show that LQR controller have a good performance on the reduction of gyroscopic effect and vibration of magnetic flywheel rotor system.

Abstract: From a new perspective, this paper explores the possibilities of constructing an index system of evaluating product quality competence for the manufacturing industry based on the analysis of the formation of the product quality in the manufacturing industry. Through utilizing the analytical instrument of linear matrix composite, the paper has conducted an empirical study based on a machinery manufacturing enterprise located in Changzhou City.

Abstract: Based on UG II CAD/CAM system, the CNC machining process and technology of a toy car cover is studied in this paper. It includes three-dimension (3D) modeling, machining programming, fixture design and manufacturing, process parameter setting, tool path planning and editing, NC code generation (post processing), simulation processing, and practical machining. The part is manufactured successfully in a 3-axis CNC milling machine. It has a desirable shape and high accuracy. The result shows that, with the powerful CAD/CAM capabilities of UG, the integrated design and manufacturing of complex curved surface shell part is easy to implement, the process is reasonable and efficient, and the NC program is reliable. This exmple fully reflects the advantages of UG CAD/CAM integration technology. The method and technology introduced in this paper can provide valuable reference for processing of similar parts.

Abstract: The transfer function of the BUCK converter is proposed by using the state-space average method. The lead-lag network is used to optimize the stability of the closed-loop BUCK system. And the stability of the system has been greatly improved. At last the simulation model of the system is founded by using the Matlab software. Compared with the results of the simulation of open-loop and closed-loop system, the conclusion can be reached that the stability of the after- compensator system is greatly improved.

Abstract: The less-ideal statement between Chinese commercial chambers and Chinese government holds back more/deeper development in commercial chambers. Based on a few basic theories such as public management, non-profit organizations and entrusted agent, this article draws lessons from the practice in developed countries and analyses the relations between commercial chambers and the government in China. It also puts forward some suggestions of corresponding measures in perfecting and creating the relations between the two sides.