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To eliminate the influence of motor parameter mismatch on finite control set model predictive current control (FCS-MPCC), a parameter robust FCS-MPCC for surface permanent magnet synchronous motor (SPMSM) drives is proposed. First, the incremental prediction model (IPM) is introduced, which eliminates the flux linkage parameter; moreover, the parameter sensitivity analysis shows that the influence of resistance parameter mismatch on IPM can be ignored. Second, an inductance information extraction strategy is proposed, which can extract the actual inductance information according to the current prediction errors of IPM. Therefore, the proposed FCS-MPCC based on IPM is robust to all motor parameters. In addition, to ensure the correctness and stability of the inductance information extraction strategy, a parameter update mechanism is introduced, in which the inductance information is updated only when the switching states of the first two control periods are different. Finally, the comparative simulation and experiments are carried out, and the results show that the proposed FCS-MPCC is not influenced by the mismatch of any motor parameters and always has better current tracking performance than traditional FCS-MPCC.

Nanocrystals exhibit significant advantages in improving the oral bioavailability of poorly soluble drugs. However, the complicated absorption properties of nanocrystals and the differences in physiological characteristics between children and adults limit pediatric applications of nanocrystals. To elucidate the absorption differences and the underlying mechanisms between children and adults, the pharmacokinetics and tissue distribution of aprepitant crystals with different particle sizes (NC200, NC500, and MC2.5) in rats and mice at different ages were studied, and their absorption mechanisms were investigated in Caco-2 cells, mice, and rats. It was found that childhood animals demonstrated higher bioavailability compared with adolescent and adult animals, which was related to higher bile salt concentration and accelerated drug dissolution in the intestine of childhood animals. The majority of nanocrystals were dissolved and formed micelles under the influence of bile salts. Compared with intact nanocrystals, the bile salt micelle-associated aprepitant was absorbed through the chylomicron pathway, wherein Apo B assisted in the reassembling of the aprepitant micelles after endocytosis. Higher bile salt concentration and Apo B expression in the intestines of childhood animals are both responsible for the higher chylomicron transport pathways. Elucidation of the chylomicron pathway in the varied absorption of nanocrystals among children, adolescents, and adults provides strong theoretical guidance for promoting the rational and safe use of nanocrystals in pediatric populations.