针对欠驱动机械臂系统的快速稳定控制中存在着的系统过程噪声和传感器观测噪声的干扰问题,设计了具有回路传输恢复的线性二次高斯(linear quadratic Gaussian control with loop transfer recovery, LQG/LTR)控制器。该控制器由卡尔曼...针对欠驱动机械臂系统的快速稳定控制中存在着的系统过程噪声和传感器观测噪声的干扰问题,设计了具有回路传输恢复的线性二次高斯(linear quadratic Gaussian control with loop transfer recovery, LQG/LTR)控制器。该控制器由卡尔曼滤波器和最优状态反馈增益调节器两部分组成,并进一步使用了回路传输恢复技术提高了控制系统稳定裕度。仿真试验表明:LQG/LTR控制方法相比于线性二次型调节器控制方法具有更加出色的动态品质,能很好地抑制噪声造成的系统不稳定问题,使得机械臂快速稳定在期望位置,具备良好的稳定性和鲁棒性。展开更多
A novel rice d1 mutant was identified using map-based cloning and comparative analysis of known dl mutants.The mutant[d1-a) shows a mild dwarf trait,which differs only slightly from the wildtype in plant height at the...A novel rice d1 mutant was identified using map-based cloning and comparative analysis of known dl mutants.The mutant[d1-a) shows a mild dwarf trait,which differs only slightly from the wildtype in plant height at the tillering stage.The dl-a mutant is different from other dl mutants.We found that it was interrupted by an Osr4 long terminal repeat(LTR)-retrotransposon,which resulted in the loss of exon 7 in the mutant D1 mRNA.A paralog of the D1 gene.D1-like,was revealed.D1-like is a truncated gene that might have resulted from recombination between retrotransposons.We identified 65 Osr4LTR-retrotransposons in Nipponbare,and found more LTR variants in contrast to coding DNA sequence(CDS) in the retrotransposons.We also identified five possible regulatory motifs in LTRs which may control the expression of the retrotransposons.In addition,we predicted six putative functional Osr4 retrotransposons that contain complete CDSs and all important elements.Osr4 retrotransposons were classified into 4 groups,and this type of retrotransposon only appears to be present in monocots.Members of group 1-1,which included all putative functional retrotransposons,showed a high similarity with each other.The retrotransposons were expressed in all tissues,at especially higher levels in some leaves and seeds.These findings imply that transpositions of group 1-1 members might have occurred frequently and recently.展开更多
文摘针对欠驱动机械臂系统的快速稳定控制中存在着的系统过程噪声和传感器观测噪声的干扰问题,设计了具有回路传输恢复的线性二次高斯(linear quadratic Gaussian control with loop transfer recovery, LQG/LTR)控制器。该控制器由卡尔曼滤波器和最优状态反馈增益调节器两部分组成,并进一步使用了回路传输恢复技术提高了控制系统稳定裕度。仿真试验表明:LQG/LTR控制方法相比于线性二次型调节器控制方法具有更加出色的动态品质,能很好地抑制噪声造成的系统不稳定问题,使得机械臂快速稳定在期望位置,具备良好的稳定性和鲁棒性。
基金supported by National and Fujian Provincial Natural Science Foundation(No.31371557 and K55NI921A)Fujian Provincial Department of Education Project(K58MLV03A)a startup fund from Fujian Agriculture and Forestry University(http://www.fafu.edu.cn/)to X.S
文摘A novel rice d1 mutant was identified using map-based cloning and comparative analysis of known dl mutants.The mutant[d1-a) shows a mild dwarf trait,which differs only slightly from the wildtype in plant height at the tillering stage.The dl-a mutant is different from other dl mutants.We found that it was interrupted by an Osr4 long terminal repeat(LTR)-retrotransposon,which resulted in the loss of exon 7 in the mutant D1 mRNA.A paralog of the D1 gene.D1-like,was revealed.D1-like is a truncated gene that might have resulted from recombination between retrotransposons.We identified 65 Osr4LTR-retrotransposons in Nipponbare,and found more LTR variants in contrast to coding DNA sequence(CDS) in the retrotransposons.We also identified five possible regulatory motifs in LTRs which may control the expression of the retrotransposons.In addition,we predicted six putative functional Osr4 retrotransposons that contain complete CDSs and all important elements.Osr4 retrotransposons were classified into 4 groups,and this type of retrotransposon only appears to be present in monocots.Members of group 1-1,which included all putative functional retrotransposons,showed a high similarity with each other.The retrotransposons were expressed in all tissues,at especially higher levels in some leaves and seeds.These findings imply that transpositions of group 1-1 members might have occurred frequently and recently.