The traditional robust controller is designed to meet the requirement considering both the disturbance and the plant uncertainty while the controller uncertainty is always neglected.The structural optimal robustness o...The traditional robust controller is designed to meet the requirement considering both the disturbance and the plant uncertainty while the controller uncertainty is always neglected.The structural optimal robustness of the closed-loop system is proposed based on the analysis of the robust radii of both the plant and the controller.The subspace angle is introduced to measure the "distance" of two subspaces,and its metric is equivalent to the gap metric.The optimal robust controller based on gap metric is designed to control the rate of the line of sight for an electromechancial target tracking system.It is shown from simulations that the optimal robust controller with the biggest robust radius is superior on the ability of disturbance rejection,and high tracking performance when additive uncertainty exists compared with the robust controller with smaller robust radius.展开更多
In this study,we investigate the robustness of pair structures for nuclear yrast states,that is,whether the structures of relevant collective pairs as building blocks of different yrast states are the same.We focus on...In this study,we investigate the robustness of pair structures for nuclear yrast states,that is,whether the structures of relevant collective pairs as building blocks of different yrast states are the same.We focus on deformed and transitional nuclei and study the yrast states of^(28)Si,^(50)Cr,and^(132)Xe,whose experimental R_(4/2)values are 2.60,2.40,and 2.16,respectively,using the nucleon-pair approximation(NPA)and shell-model effective interactions.For each yrast state,we consider optimized pair structures to be those providing the energy minimum for this state.To find the minimum,many full NPA calculations are performed with varying pair structures,and the numerical optimization procedure of the conjugate gradient method is implemented.Our results suggest that optimized pair structures remain the same for all states within a rotational band of a deformed nucleus.Our results also suggest that after backbending,that is,changing of the intrinsic state,the structure of the S pair,which is essential to build the monopole pairing correlation,remains approximately unchanged,whereas the structures of the non-S pairs,which are essential to build the quadrupole correlation,change significantly.展开更多
基金Sponsored by the Science and Technology Project of the Department of Education of Heilongjiang Province(Grant No.12511015)the Defense Pre-Research Project of China (Grant No.51309040201)
文摘The traditional robust controller is designed to meet the requirement considering both the disturbance and the plant uncertainty while the controller uncertainty is always neglected.The structural optimal robustness of the closed-loop system is proposed based on the analysis of the robust radii of both the plant and the controller.The subspace angle is introduced to measure the "distance" of two subspaces,and its metric is equivalent to the gap metric.The optimal robust controller based on gap metric is designed to control the rate of the line of sight for an electromechancial target tracking system.It is shown from simulations that the optimal robust controller with the biggest robust radius is superior on the ability of disturbance rejection,and high tracking performance when additive uncertainty exists compared with the robust controller with smaller robust radius.
基金Supported by the National Natural Science Foundation of China(11875134,11875188,12175071,11975151,11961141003)the Shanghai Key Laboratory of Particle Physics and Cosmology(21DZ2271500-2)。
文摘In this study,we investigate the robustness of pair structures for nuclear yrast states,that is,whether the structures of relevant collective pairs as building blocks of different yrast states are the same.We focus on deformed and transitional nuclei and study the yrast states of^(28)Si,^(50)Cr,and^(132)Xe,whose experimental R_(4/2)values are 2.60,2.40,and 2.16,respectively,using the nucleon-pair approximation(NPA)and shell-model effective interactions.For each yrast state,we consider optimized pair structures to be those providing the energy minimum for this state.To find the minimum,many full NPA calculations are performed with varying pair structures,and the numerical optimization procedure of the conjugate gradient method is implemented.Our results suggest that optimized pair structures remain the same for all states within a rotational band of a deformed nucleus.Our results also suggest that after backbending,that is,changing of the intrinsic state,the structure of the S pair,which is essential to build the monopole pairing correlation,remains approximately unchanged,whereas the structures of the non-S pairs,which are essential to build the quadrupole correlation,change significantly.
