Applied Mechanics and Materials Vols. 128-129

Abstract: In China, the thermal power is the main structure of power source. We consider that analysis thermal power’s date generation process is very important to precise planning of thermal power and whole electricity market. For testing the impact of inspection and external factors on thermal power, we study date generation process of thermal power by structural change model that carry unit root test and trend stationary test. This conclusion indicates that thermal power’s date generation process is the unit root process of structure change and isn’t trending stationary process.

Abstract: The mathematical simulations of the galvanic coupling intra-body communication (IBC) with different signal transmission paths have been introduced. Firstly, a galvanic coupling IBC circuit model was developed and the transfer function was derived. Secondly, the corresponding parameters were discussed. Finally, the signal attenuation characteristics of the galvanic coupling IBC were measured along the different signal transmission paths of the actual human bodies, while the corresponding mathematical simulations based on the proposed transfer function were carried out. A close agreement between the simulation results and measurement results has been demonstrated.

Abstract: In order to definite the dynamic properties of full mounted converter tilting mechaism and analysis the mechanical condition of the main transmission parts in the operation process, the dynamics behavior of the converter tilting mechaism was analysied. Vibration properties of the mechaism was analyzed by using mode shapes analysis method in no external force and an external force two circumstances, tilting mechanism can be constructed 11 degree of freedom force modal, and it can further simplify 3 degrees of freedom force modal. It can find resonant frequency of tilting mechaism through the analysis of the torsion vibration angular displacement and the torsion torque. It can provide scientific basis for equipment maintenance of technical personnels.

Abstract: Construct the model of the end-point ingredient prediction of low carbon ferrochrome smelt based on the working condition of electrothermal silicon method using the method of multi-scale support vector machiness information fusion, where the best decomposition scale information is according to different smelt working conditions using Levenberg-Marquart algorithm to optimize the design, smelt working condition is judged by Bayesian classifier. Researches have proved that this method can improve the precision of prediction and make the prediction result more accurate, reasonable and practical.

Abstract: Based on the measurement of train speed, this paper briefly describes the basic principle of Doppler speed measurement and the design of speed measurement system. By the analysis of test signal which simulates the actual speed signal and comparison of the simulation results, the AR power spectrum estimation algorithm is selected as the model of speed measurement system, and the Burg method is selected to evaluate the Doppler frequency. Then the effect of parameters such as sampling frequency, length of the input vector, FFT length and estimation order on power spectrum estimation are analyzed, the optimization principles of the parameters are defined. Finally, the determined method is simulated with a high-noise, multi-jamming signal and has good results. The accuracy, stability and immunity are proved by the simulation.

Abstract: Study focusing on the dynamics of the crystallizer hydraulic non-sinusoidal vibration system in the bullet caster crystallizer, which is employed in an electric furnace factory, is introduced. With respect to construct a mathematical model of continuous casting crystallizer hydraulic vibration system, a power band graph method is applied. With the utilization of this method, a process of modeling and evaluating the performance of the hydraulic cylinder, electric-hydraulic servo and sensor system is conducted. The system is also analyzed and simulated by MATLAB/SIMULINK. In our experiment, the performance of the crystallizer non-sinusoidal vibration system with the change of main parameters is studied. Furthermore, an experiment is also conducted aims at investigating the quality requirements for the servo system, including stability, rapidity, and accuracy. Furthermore, an experiment is also conducted aims at investigating the quality requirements for the servo system, including stability, rapidity, and accuracy. The results demonstrate that crystallizer hydraulic servo non-sinusoidal vibration system can satisfy high frequency steel ball requirements and small amplitude design requirements. In addition, it can effectively improve the surface quality of casting blank.

Abstract: In this paper, the model of three-axis dual rotor helicopter is built, through a new motor control algorithm of real-time grouping, the decoupling and independent control of pitch, yaw and roll channels is realized; then the “dead zone” is introduced to design the attitude controller on the basis of the optimal control law which minimize the weighted sum of response time and energy consumption, to achieve optimal control of the attitude of the helicopter; finally, the simulation model of the attitude control system is established in the MATLAB/Simulink environment. Simulation results show the feasibility of the optimal attitude controller design.

Abstract: With the development of wireless communication, the automatic modulation recognition technology of communicational signals becomes an important theme. In this paper, based on multivariate statistical principal component analysis, we select characteristics of the signal, and use radio monitoring equipment mined measurement data to do some processing and analysis, which provided technical support to automatic modulation recognition of the radio signal.

Abstract: Based on the plastic-elastic method, the 3-D milling FEM analysis model is established in this paper, which simulates the material removal process. This paper studies the release of initial residual stress how to affect the deformation in different structure parts. Compared with the results of simulation and experiment, it can be drawn a conclusion that the symmetric release of the residual stress facilitates to reduce the machining deformation.

Abstract: Adopted the theory of elastic-plastic deformation, used the FEM analysis software, the reasonable two-dimension heat-mechanic coupling orthogonal cutting model is established in this paper, which uses the adaptive meshing criteria and simulates a typical work-piece chip breaking process. This paper simulates different tool orthogonal rakes how affect the cutting process, which is very significant in engineering. This paper supplies the theory foundation of optimizing the technical parameters and deeply studying the cutting mechanism.