fall of current meaning in Chinese

电流下降

The method proposed in this thesis do well in solving the problems of multi - damping - ratio - spectra simulation . it is convenient to obtain the pareto optimal solution set of the multi - object question by using implicit parallel genetic algorithms and the method can meet the practical needs for simulating ground motions coinciding with multi - damping - ratio - spectra in seismic design . the crossing rate and variance rate are important parameters of genetic algorithms which affect the rate of convergence , the adapting rate of cross and variation in this paper can auto - adapt and according to stand or fall of current sample , it assures the sample approach to the pareto optimal solution set in fast convergent speed
较好地解决多阻尼比反应谱拟合问题；本文方法通过一次运行就能获得一组具有集系特性的地震动，在拟合多阻尼比反应谱的人造地震波集系的仿真方面有传统方法所不能比拟的优势，产生的人造波或人造波集系可满足工程抗震设计需要；在遗传算法中，交叉概率和变异概率是影响收敛速度的重要参数，本文采用的改进自适应交叉概率和变异概率，可以根据当前样本的好坏程度来自动地选择适当的交叉概率和变异概率，以保证算法始终以较好的速度向pareto最优解集逼近。