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The calculated result of the mathematical model based on the conventional transfer function has bigger deviation than the measured. In this paper the mathematical model of the work roll bending is derived. The modeling is different from conventional modeling used many presumptions and linear processing. The modeling calculated accurately the equivalent load spring using the method of influence function. The simulation results agree well with actual data of the bending system.

This paper analyzes the effect of stable behaviors when amplitude, phase of sine voltage compensation signal are added in the system, reveals that the dynamical behaviors mechanism that sine voltage compensation signal changes feedback voltage-mode controlled buck converter lies in changing the duty cycle without impacting the system stable error via analyzing the change of period multiplier in Monodromy matrix and conditions of period bifurcation, and finally achieves stabilization control for bifurcation and chaotic behaviors. The simulation and experimental results prove the correctness of the theoretical analysis.

The Variable Forward-Swept Wing (VFSW) Tailless configuration UAV can well satisfy multipurpose demands. However, this kind of unconventional morphing aircraft lacks tail, which brings great challenge to stability analysis. The connatural aero-elasticity divergence and the strong aerodynamic coupling as well as many uncertain factors in mechanical environment, give the VFSW Tailless configuration UAV complicated dynamic characteristics. During the process of transformation, the variation of dynamic shape will inevitably lead to the variation about aerodynamic center and barycentre positions of airplane, then make the angle of attack static stability margin variable, and directly influence stability of aircraft. On the basis of introduction of the VFSW Tailless configuration UAV, according to its geometric shape, positions of aerodynamic center and barycentre, in different states with different forward-swept angle, were calculated, so as to obtain variation curve of longitudinal static stability margin, which provided preferences for dynamics analysis, position of barycentre adjustment and design of flight control system (FCS).

Based on the variable forward-swept wing configuration, this paper utilized a variable forward-swept wing mechanism with a double slideways, which make it possible for the aircraft to switch among orthogonal wing, forward-swept wing and delta wing freely. The general configuration of the variable forward-swept wing mechanism with a double slideways was elucidated by means of a three-dimensional model plot and then the mathematic simulation model was also established. The motion characteristics of linear motion were simulated, analyzed and optimized. The results indicated that the variable forward-swept wing mechanism with a double slideways can meet the aerodynamic requirements better. Moreover, there exists great linear relationship between the position of nut and the wing forward-swept angle. Therefore, this mechanism may serve as a useful reference when developing a morphing aircraft.

In this article,take into account QoS characteristics comprehensively and build a reliable QoS ontology model. Based on the model,Web service QoS matching will be divided into three stages.Firstly,make a estimation of semantic comparability between QoS parameters of candidate services meeting the functional requirements and the QoS parameters of requirements in QoSIndependent ontology,find candidate services meeting users needs; Then,according to the critical QoS parameters between adjacent services constraints to further refine the matching between the candidate services;Finally choose the maximum service QoS value meeting the user requests in specific areas. So as to improve the efficiency and accuracy of service matching.

A case study of typical mold parts, combining the Structure characteristics of the parts and considering various phenomena that may occur during the processing of the parts, we finally worked out a reasonable scheme. In addition, according to optimize processing technology, we select Mastercam software for auto-programming and machining simulation, achieving high precision and high efficiency machining of the parts and improving economic efficiency of enterprises. Conclusions in this paper give a valuable reference to machine mold parts.

Continuous extrusion under the large expansion ratio is an advanced forming process for manufacturing copper strip, preventing mould structure, die structure, expansion chamber structure and the shape of the billet section is important process paraments of deformation. Based on the characteristic of the forming process, the model of rigid-plastic FEM on DEFORM-3D is established and the numerical simulation of continuous extrusion forming process of the copper strip is carried. The metal flow regularity and the mean-square deviation of velocity with the different process paraments is analyzed. As the result, when using the drum form of preventing mould with promote flow angle and the die with variable calibrating strap, the mean-square deviation of velocity is 0.58. When the second extending angle is 134°, the mean-square deviation of velocity is 0.23. When size of billet is 30 x 1.64 mm2, the mean-square deviation of velocity is only 0.19.

The prediction accuracy of the simulation of cutting process is related with the description of the nonlinear behavior of material at extremely high strain, strain rate and temperature in machining. In this paper, an integral Johnson-Cook model is presented to characterize the mechanical behavior of work materials in machining, and the parameters in the model are determined by fitting the data from both quasi-static compression and cutting tests. Then the material equation of 2Cr13 stainless steel is derived with this method and used in the finite element model of orthogonal cutting with carbide tools. At last, the simulation result is verified with experimental data.