传统导弹姿控系统通常在极限拉偏状态下设计控制参数,存在设计余量过大的问题。针对导弹姿态控制系统精细化设计要求,基于概率论和可靠性思想,提出了一种导弹姿控参数概率设计方法。此方法将姿控系统时域频域指标设计为概率形式,将姿控...传统导弹姿控系统通常在极限拉偏状态下设计控制参数,存在设计余量过大的问题。针对导弹姿态控制系统精细化设计要求,基于概率论和可靠性思想,提出了一种导弹姿控参数概率设计方法。此方法将姿控系统时域频域指标设计为概率形式,将姿控参数设计问题转化为满足概率型指标的参数优化问题。考虑各种偏差的概率分布特性,基于二阶可靠度法(Second Order Reliability Method,SORM)对极限状态方程的超曲面进行二阶近似,进而估计系统各项性能指标的满足概率,并采用改进粒子群算法求解优化问题。与传统姿控参数设计方式仿真相比,该方法可使最大控制力矩减小22.79%,有效削减了姿控系统设计余量,同时,相较于蒙特卡罗法,所采用的SORM能大幅度提高概率计算效率。展开更多
In this paper, we investigate the stationary probability distribution and mean first passage time in a vegetation ecological system, which is driven by cross-correlation between intrinsic and extrinsic colored noises ...In this paper, we investigate the stationary probability distribution and mean first passage time in a vegetation ecological system, which is driven by cross-correlation between intrinsic and extrinsic colored noises as well as the nonzero cross-correlation in between. The impacts of the self-correlation time τ1 and τ2, the cross-correlation time τ3 and intensity k on the stationary probability distribution and mean first passage time are discussed, respectively. Our main results show that:(i) the self-correlation time τ1 can induce regime shifts from the desert state to the sustainable vegetation state, while the self-correlation time τ2, cross-correlation time τ3 and intensity k can induce regime shifts from the sustainable vegetation state to the desert state; and(ii) the self-correlation time τ1 or τ2 can enhance the stability of the sustainable vegetation biomass, while the cross-correlation time τ3 or strength k weakens the stability of the sustainable vegetation biomass.展开更多
文摘传统导弹姿控系统通常在极限拉偏状态下设计控制参数,存在设计余量过大的问题。针对导弹姿态控制系统精细化设计要求,基于概率论和可靠性思想,提出了一种导弹姿控参数概率设计方法。此方法将姿控系统时域频域指标设计为概率形式,将姿控参数设计问题转化为满足概率型指标的参数优化问题。考虑各种偏差的概率分布特性,基于二阶可靠度法(Second Order Reliability Method,SORM)对极限状态方程的超曲面进行二阶近似,进而估计系统各项性能指标的满足概率,并采用改进粒子群算法求解优化问题。与传统姿控参数设计方式仿真相比,该方法可使最大控制力矩减小22.79%,有效削减了姿控系统设计余量,同时,相较于蒙特卡罗法,所采用的SORM能大幅度提高概率计算效率。
基金Supported by the National Natural Science Foundation of China under Grant No.11305079the Introduction of Talent Capital Group Fund Project of Kunming University of Science and Technology under Grant No.KKZ3201407030
文摘In this paper, we investigate the stationary probability distribution and mean first passage time in a vegetation ecological system, which is driven by cross-correlation between intrinsic and extrinsic colored noises as well as the nonzero cross-correlation in between. The impacts of the self-correlation time τ1 and τ2, the cross-correlation time τ3 and intensity k on the stationary probability distribution and mean first passage time are discussed, respectively. Our main results show that:(i) the self-correlation time τ1 can induce regime shifts from the desert state to the sustainable vegetation state, while the self-correlation time τ2, cross-correlation time τ3 and intensity k can induce regime shifts from the sustainable vegetation state to the desert state; and(ii) the self-correlation time τ1 or τ2 can enhance the stability of the sustainable vegetation biomass, while the cross-correlation time τ3 or strength k weakens the stability of the sustainable vegetation biomass.
