Applied Mechanics and Materials Vol. 203

Abstract: The comparison of the hyperbolic perturbation method and the hyperbolic Lindstedt-Poincaré method for homoclinic solutions of self-excited systems is studied in this paper. The homoclinic solution of a generalized Van del Pol system with strongly quadratic nonlinearity is analytically derived by both of the methods. The critical value of the bifurcation parameter under which homoclinic trajectory forms can be determined by the both of the perturbation procedures. Typical numerical examples are studied in detail and compared to illustrate the accuracy and the efficiency.

Abstract: Ower quality is becoming a more concern of today’s power system engineer due to the rapid growth of non-linear loads, such as power electronic control equipment and electric arc furnace (EAF). Harmonics and voltage flicker are the power quality problems which are introduced to the power system as result of non-linear behavior of the electric arc furnace operation. There are numbers of arc furnace models. This paper presents a time domain model which is used to study its behavior on the power system using MATLAB. To analyze the method, several characteristics for different operating conditions are investigated.

Abstract: Portable personal electric scooter has the application of great development potential. This paper first studied overall scheme optimization design, and then the division a optimized and design, includes Motor and transmission Optimized selection , Battery energy system Optimized selection, Motor driver and vehicle control circuit, Charging system research finally draw optimization design results and related parameters.

Abstract: Use the simple geometric features of a one-dimensional model to calculate the rotor critical speed, the shaft use the beam element to simulate, considering the shear deformation, continuous mass, the rotation inertia and gyro effect, bearing simplified as linear stiffness and damping element, disc use the lumped mass element to simulate, considering the mass and the effect of inertia, finite element method is applied, established the rotor-bearing system dynamics model, through the example to validate, the results show that the model is the advantage of calculation on a smaller scale, solution speed and high precision, easy to adjust the parameters for the model, suitable for large needs to adjust the parameters in the early stage of design and analysis of the rotor-bearing system, it has great reference value for the design and analysis of rotor dynamics.

Abstract: The global integration time step of multi-scale model is subject to local detailed model, resulting in lower computational efficiency. Mixed time integration method uses different integration time-step in different scale model, it can effectively avoid the above problem. Rest on a large-scale water tunnel under construction, in order to achieve the synchronization of the global and the local simulation, the paper establishes multi-scale finite element model of the tunnel, and calculate it by mixed time integration method. The final calculation and analysis show that the algorithm can guarantee the computational accuracy of multi-scale numerical simulation, and can effectively improve the computational efficiency, it can also provide references for related tunnel project.

Abstract: Physical model of angle nozzle was established. Based on the CFD software of FLUENT, the flow field about cavitating water jet in angle nozzle was simulated by use of mixture model, Singhal complete cavitation model, RNG turbulent model and SIMPLEC algorithm. The simulation results show that there are two low pressure regions and two regions of high volume fraction of steam in angle nozzle. The region of high volume fraction of steam corresponds with low pressure region. The region of high volume fraction of steam mainly lies near the exit of column section and approximates to a semicircle. In this region, the volume fraction of steam reaches the maximum value at a point of on-wall. Taking that point as the centre, the volume fraction of steam decreases gradually from interior to exterior.

Abstract: With the quickly development of fiber communication, PMD(Polarization mode dispersion) has became one of the key factor which limit high-bit rate system performance. In 1986, C.D.Poole[1] and other people found that if do not consider loss of SOP, two upright PSP will change along certain length SMF. In 1987, D.Andresciani and N.S.Bergano validate the theory of C.D.Poole each either. Late ninety of last century, statistical theory forming[2]. In the paper, we discuss the study of PMD, including statistics of PMD, measure technology, the affect of system by PMD, and PMD Compensation Method.

Abstract: The article introduces the design scheme of a motion control card on PXI bus. A detailed description of PCI interface module, FPGA module, DSP module, serial transceiver module and analog acquisition module is also given in this paper. Tests of data transfer rate between host and motion control card are adopted, the results suggest that the PXI local bus can get a high-rate communication. The motion control card is applied to control the two-dimensional turntable of an optoelectronic imaging and tracking system. The experiments indicate that the motion control card based on PXI can meet the requirements of real-time control. The performance of control is also acceptable.

Abstract: The simulation results and the analysis of 3d body movement is still a difficult and hot issue. Although domestic and international counterparts is in a human body movement simulation has some results but they really difficult to meet demand, because height of the complexity of the calculation, or the need to put heavy parameters. Study the hot topic of object-oriented simulation system simulation method, qualitative simulation, distributed interactive simulation, virtual simulation, the multimedia simulation, simulation based on virtual reality.

Abstract: Based on the remanufacturing reverse supply chain consisted of single retailer and single manufacturer, this paper applied game theory to establish a non-cooperative game and cooperative game model and got optimal pricing strategy by solving this two kinds of game model. By comparing the total profits of reverse supply chain in every game model, a conclusion was draw that non-cooperative game model led to profit loss and double marginal effect. In order to solve the problems, revenue sharing contract was used to coordinate the reverse supply chain and coordinating strategy was got. The results show that revenue sharing contract can increase the total profits of the reverse supply chain, while at the same time meet the respective interests of retailer and manufacturer and coordinate the reverse supply chain.