Abstract: . A novel fault diagnosis method for centrifugal compressor was proposed by using entropy- based fuzzy gray relational analysis (EF-GRA). Firstly, the minimize entropy principle (MEP) was used to subdivide all real-valued fault features and construct membership functions of fuzzy variables. Secondly, based on the gray theory, the fuzzy-gray relational coefficients (F-GRC) were calculated and the weighted fuzzy-gray relation degrees (WF-GRD) were obtained, so that the diagnostic result can be determined. Finally, a centrifugal compressor fault dataset was used to illustrate the proposed method, and the results show that it has strong engineering practicability and validity.
Abstract: For developing motor driven automated mechanical transmission of hybrid electrical vehicle, adjust and control the gear selecting motor, the gear shifting motor and the clutch motor. In the research of position-PID controller and robust disturbance observer, an automated mechanical transmission system based on position-PID was given. With Matlab, the position-PID controlling arithmetic and the controlling system models of the motors were built. Experimental results show that, a highly efficient and reliable automated mechanical transmission motor control system was developed.
Abstract: In order to improve the reliability and comfortableness of driving, network used in automobile air-condition control system have been studied in this paper and we also designed a automobile air-condition control system based on CAN bus. The control system can improve the reliability of driving, it interconnects the air-condition system with other automobile CAN buses, which accelerating the automobile integration process. To optimize the control of vehicle air-condition system, we can improve and enhance the performance of conventional automobile air-condition, it is the key technology with a good prospect in the turning of electronic automobile control to the advanced stage.
Abstract: Perfect automotive air conditioner system can be improved to ensure pleasant air environment in a variety of external conditions, the driver can keep the brain cool, improve work efficiency, reduce fatigue and accidents, and thus guarantees driving safety. Because of the transient nature of automotive air conditioner and systematic non-linear, it is extremely difficult to establish the mathematical model for the system. Generally, to describe the transfer function or the state function of automobile air conditioner accurately is difficult, the control of the system can rarely obtain satisfying results. This article explored the procedures of introducing the digital PID control algorithm into the automotive air conditioner control system, and proposed an automobile air conditioner intelligent control system based on Increment-PID algorithm. Optimized control of automotive air conditioner system can improve its performance.
Abstract: Based on a laminated composite structure, vibration and nonlinear stall aeroelastic stability of rotor blades modeled as anisotropic thin-walled closed-section beams are systematically addressed. The analysis is applied to a laminated construction of the circumferentially asymmetric stiffness (CAS) that produces bending-bending-twist coupling. The vibration characteristics of composite beam are determined by the Galerkin Method. The unsteady aerodynamic loads and centrifugal force are integrated with the nolinear aerodynamic model to deal with aeroelastic stability analysis. The influence of some related factors, pretwisted angle, ply-angle rotational speed, and wind speed, is investigated. The paper gives methods of eigenvalue analysis and aeroelastic response, which can determine the stability of the blade forced by the nolinear aerodynamics.
Abstract: This paper presents the results of experimental analysis and theoretical modeling of piezoelectric stack actuators. The focus of this paper is to understand the behavior of piezoelectric materials under the combined electro-mechanical loadings scenario, and to determine fundamental properties and optimum working conditions. Some parameters, including output displacement, hysteresis, output force and mechanical stiffness, are evaluated under varied pre-stress level and driven voltage values representative of in-service conditions. The measurements indicate strong dependence of the actuator piezoelectric properties and stiffness on the electro-mechanical loading conditions. This research also identified and calculated some parameters of the induced strain actuators electro-mechanical model, which are necessary to performing design optimization to achieve maximum energy transfer and minimum power consume.
Abstract: The frame theory has been one of powerful tools for researching into wavelets. The notion of the bivariate generalized multiresolution structure (BGMS) is presented. The concepts of Bessel sequences and orthogonal bivariate pseudoframes are introduced. Two Bessel sequences are said to be orthogonal ones if the composition of synthesis operator of one sequence with the analysis operator of the other is the zero-operator. It is characterized that when two Bessel sequences are orthogonal while the Bessel sequences possess the form of translates of a finite number of bivariate functions in . A constructive method for affine frames of based on a BGMS is established.