In this paper the simple generation algorithms are improved. According to the geometric meaning of the structural reliability index, a method is proposed to deal with the variables in the standard normal space. With c...In this paper the simple generation algorithms are improved. According to the geometric meaning of the structural reliability index, a method is proposed to deal with the variables in the standard normal space. With consideration of variable distribution, the correlation coefficient of the variables and its fuzzy reliability index, the feasibility and the reliability of the algorithms are proved with an example of structural reliability analysis and optimization.展开更多
In this paper, the problem of reliability-based optimal design of simple offshore platform is studied, and a nonlinear fatigue damage model based on damage mechanics and genetic algorithms are used in the fatigue reli...In this paper, the problem of reliability-based optimal design of simple offshore platform is studied, and a nonlinear fatigue damage model based on damage mechanics and genetic algorithms are used in the fatigue reliability optimum design of the structure under stochastic wave load. The fatigue damage model and the yield failure reliability analyzing model are used in the paper. The reliability of the models and the effectiveness of genetic algorithm are shown by the results of optimum design.展开更多
Under the mechanically free and clamped boundary conditions, electromechanical resonances-of ceramic multilayer capacitors are calculated using vibration and piezoelectric equations. Multilayer capacitors made of ferr...Under the mechanically free and clamped boundary conditions, electromechanical resonances-of ceramic multilayer capacitors are calculated using vibration and piezoelectric equations. Multilayer capacitors made of ferroelectric BaTiO3 and Pb(Mp(1/3)Nb(2/3))O-3 ceramics have been used to examine the theoretical calculation. Frequency spectra of impedance and phase angle, capacitance and loss tangent of the capacitors under de bias fields are carefully measured. A sudden change around the resonant frequency is observed in these spectra. A damped resonance indicates a defective capacitor while an undamped resonance is corresponding to defect free. Experimental results suggest that it is possible to use the spectra as a real time nondestructive evaluation method.展开更多
THE giant magnetoresistance(GMR)effect in magnetic multilayer has been the subject of in-tense investigation since its discovery.Various theories,including semiclassical theoryand quantum theory,have been developed to...THE giant magnetoresistance(GMR)effect in magnetic multilayer has been the subject of in-tense investigation since its discovery.Various theories,including semiclassical theoryand quantum theory,have been developed to deal with the GMR.A general view on the mi-croscopic mechanism of the GMR is the spin-dependent scattering.The origin of the展开更多
基金This work was financially supported by the National Science Foundation of China
文摘In this paper the simple generation algorithms are improved. According to the geometric meaning of the structural reliability index, a method is proposed to deal with the variables in the standard normal space. With consideration of variable distribution, the correlation coefficient of the variables and its fuzzy reliability index, the feasibility and the reliability of the algorithms are proved with an example of structural reliability analysis and optimization.
基金This work was financially supported by the National Science Foundation of China
文摘In this paper, the problem of reliability-based optimal design of simple offshore platform is studied, and a nonlinear fatigue damage model based on damage mechanics and genetic algorithms are used in the fatigue reliability optimum design of the structure under stochastic wave load. The fatigue damage model and the yield failure reliability analyzing model are used in the paper. The reliability of the models and the effectiveness of genetic algorithm are shown by the results of optimum design.
文摘Under the mechanically free and clamped boundary conditions, electromechanical resonances-of ceramic multilayer capacitors are calculated using vibration and piezoelectric equations. Multilayer capacitors made of ferroelectric BaTiO3 and Pb(Mp(1/3)Nb(2/3))O-3 ceramics have been used to examine the theoretical calculation. Frequency spectra of impedance and phase angle, capacitance and loss tangent of the capacitors under de bias fields are carefully measured. A sudden change around the resonant frequency is observed in these spectra. A damped resonance indicates a defective capacitor while an undamped resonance is corresponding to defect free. Experimental results suggest that it is possible to use the spectra as a real time nondestructive evaluation method.
文摘THE giant magnetoresistance(GMR)effect in magnetic multilayer has been the subject of in-tense investigation since its discovery.Various theories,including semiclassical theoryand quantum theory,have been developed to deal with the GMR.A general view on the mi-croscopic mechanism of the GMR is the spin-dependent scattering.The origin of the
