Search

Due to the complicated dredging operation of the cutter suction dredger, most scholars at home and abroad have used the working characteristics of the key equipment of the cutter suction dredger to carry out related research and establish its mathematical model. However, from the basic principles, it is inaccurate to establish the input-output model of the cutter suction dredger control system, which is a multi-parameter, non-linear, large time-delay system, and can not meet the needs of the actual control system. In this paper, the data-driven method is used to solve the black box problem between the control variables and the instantaneous output in the cutter suction dredger control system. The experimental results show that the predicted results of RBF neural network are reliable under different working conditions, and the model can provide accurate nonlinear mathematical model for the next model predictive control. [ABSTRACT FROM AUTHOR]

In view of the problems of complex operation and high cost of large wave-making devices with servo valve control, this paper developed a wave machine control system which is controlled by the rotary valve. It mainly designs and applies the input control of the rotational speed of the servo motor in the wave control system, the axial displacement input control of the linear stepping motor ami the system oil pressure control. Experiments have been carried out to analyze the influence of the input control parameters on the amplitude and length of the wave-making experiment platform. The results show that the variable wave control system is easy to generate regular waves with different amplitudes and wave lengths. It can make the study and experimental teaching operation process more simple, and has important reference value for hydrodynamic research and improvement of teaching experiment. [ABSTRACT FROM AUTHOR]

The magnetic 1evitation system ( MLS % is researched in this paper and configuration components, performance and functions of MLS are presented. Motion equations of simu1ated physica1 system are given. Seven experiment schemes are designed, and experiment aims and requests are given. Those experiments can he1p students to grasp the characteristics of SIS0 system, SIM0 system, MIM0 system as weH as operation methods of MLS in experiment process for the purpose of understanding PID, Po1e assignment, and LQR method, to estab1ish fundamental for their further study of actua1 contro1 systems. [ABSTRACT FROM AUTHOR]

In order to further complement the system of grey power models, this paper analyzes the transformation relationships between the classic GM(1,1) model and GM(1,1) power model, and deduces five derived models including GM(1,1,x(2)) power model, GM(1,1,x(1)) power model, GM(1,1,6) power model, GM(1,1,exp) power model and GM(1,1,C) power model based on the defined and whitened GM(1,1) power models. A group of grey power models including classic GM(1,1) power model and the derived five models is built finally. The results show that time response functions of GM(1,1) model and GM(1,1) power model are essentially the same. Different derived models have different structures, contents and solutions, reflecting the principal of non-unique solution in grey system theory. In practical applications, the most appropriate whitened solution can be identified from group of default solutions under the corresponding objectives. [ABSTRACT FROM AUTHOR]

Based on the reason that the growth of discrete grey model is constant, the paper structured quadratic time-varying parameters discrete grey model (referred to as QDGM(1,1)) by introducing quadratic time-varying terms. And then the paper researched properties of the new model, and reached the conclusion that QDGM(1,1) possessed white exponential law coincidence, linear law coincidence, quadratic law coincidence and consistency of stretching transformation. What's more, the paper applied optimization method to optimizing the iterative starting value of the new model, and introduced the steps of using QDGM(1,1) to predict. Finally, the new model was compared with another three discrete grey models through an instance. It was proved that the new model greatly improves the simulation and prediction precision. [ABSTRACT FROM AUTHOR]

For the equivalent nonlinear dynamic system of brushless DC motor, the center manifold theory and Hopf bifurcation theory are used to discuss the Hopf bifurcation behaviors of original system, the Hopf bifurcation control problem of original system is investigated using a state feedback controller, and the effects of control parameters on the position of bifurcation point, bifurcation type and amplitude of periodic solution are analyzed. The research results show that the positions of Hopf bifurcation points can be changed and even the Hopf bifurcation points are eliminated by the linear control, and the bifurcation type and the bifurcation amplitude of periodic solution can be changed by the nonlinear control. Finally, the numerical simulations show the effectiveness of the proposed controllers. [ABSTRACT FROM AUTHOR]