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Mei Xuan Xu Wen Guang Liu Yun Lin Guan Zuo Peng Bi Kang De Yao 《Polymer International》1995,38(2):205-209
The phase behavior of a hybrid polymer network (HPN) composed of poly[(propylene glycol maleate)-co-(propylene glycol phthalate)] crosslinked with styrene and polyester–urethane crosslinked with methylene-bis-ortho-chloroaniline was examined. The correlation between phase separation and impact strength of the HPNs is discussed. The composition of HPNs has an effect on their properties. 相似文献
124.
Ivan Cimrák 《Archives of Computational Methods in Engineering》2007,15(3):277-309
The Landau-Lifshitz (LL)equation of micromagnetism governs rich variety of the evolution of magnetization patterns in ferromagnetic
media. This is due to the complexity of physical quantities appearing in the LL equation. This complexity causes also an interesting
mathematical properties of the LL equation: nonlocal character for some quantities,nonconvex side-constraints, strongly nonlinear
terms. These effects influence also the numerical approximations. In this work, recent developments on the approximation of
weak solutions, together with the overview of well-known methods for strong solutions,are addressed.
Author is supported by the Fund for Scientific Research - Flanders FWO (Belgium). 相似文献
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The Uniform Geometrical Theory of Diffraction (UTD) has been successfully used in pattern analysis of airborne dipole antenna on the A-5 fighter in high-frequency region. In the analysis, several canonical problems are investigated first, then the complicated problem is calculated with compiling these canonical problems. The numerical results are compared with the experimental data, and good agreement has been seen. The effectiveness and practicality of the present analysis are thus verified. 相似文献
127.
Bugong Xu 《Automatic Control, IEEE Transactions on》1995,40(5):930-933
A new criterion for delay-independent stability of linear large scale time-delay systems is deduced by employing an improved Razumikhin-type theorem and the m-matrix properties. An illustrative example is given to demonstrate the superiority of the obtained results to those in the literature 相似文献
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129.
Xiao Sun Chow M.H.L. Leung F.H.F. Dehong Xu Yousheng Wang Yim-Shu Lee 《Power Electronics, IEEE Transactions on》2002,17(3):305-313
An analogue neural-network controller for UPS inverter applications is presented. The proposed neural-network controller is trained off-line using patterns obtained from a simulated controller, which had an idealized load-current-reference. Simulation results show that the proposed neural-network controller can achieve low total harmonic distortion under nonlinear loading condition and good dynamic responses under transient loading condition. To verify the performance of the proposed NN controller, a hardware inverter with an analogue neural network (NN) controller (using mainly operational amplifiers and resistors) is built. Additionally, for comparison purposes, a PI controller with optimized parameters is built. Experimental results confirm the simulation results and show the superior performance of the NN controller especially under rectifier-type loading condition. Implementing the analogue neural-network controller using programmable integrated circuits is also discussed 相似文献
130.