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In order to reduce the impact of thruster dead zone on remotely operated vehicle (ROV) motion performance and ensure that it can complete trajectory tracking control under external interference. In this paper, the adaptive backstepping sliding mode control(ABSMC) method based on improved rapid power-to-power approximation law is proposed. Under the influence of external interference; ABSMC can quickly reduce the position error of the system, namely, shorten the approaching time. When the position error is small, the system can smoothly enter the sliding surface to eliminate chattering. A new thrust distribution method based on the pseudo-inverse method is proposed for the dead zone of a thruster. This method uses the pseudo-inverse method when the thrust is saturated. When all thruster thrusts are unsaturated, the thrust will remain outside the dead zone for a long time. Combined with the ABSMC method, the thrust output of the thruster is more smooth and more stable with small position errors. Finally, the effectiveness of the ABSMC method and the superiority of the new thrust distribution method is verified by simulation experiments.

In traditional Chinese Medicine, Prunella vulgaris L. (PVL) is potentially effective in the treatment of some human malignancies including hepatocellular carcinoma (HCC). However, the detailed mechanism of action remains unclear. The purpose of this study was to decipher the constitutes of the bioactive ingredients of PVL, and its mechanism against HCC using network pharmacology and in vitro experiments. The bioactive components of PVL were obtained by Traditional Chinese Medicine System Pharmacology Database and Analysis platform database, and the targets of bioactive components of PVL was investigated by Swiss Target Prediction database. HCC related targets were obtained from GEO database, GeneCards database and DisGeNET database, and the gene ontology function annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted for annotating the biological function of gene targets. A protein–protein interaction network was constructed using STRING database. Molecular docking of key bioactive ingredients was performed using AutoDock Vina. Cell proliferation and apoptosis were detected by cell counting kit‐8 and flow cytometry, respectively. The expression level of the target genes of PI3K/Akt pathway were detected by qPCR. In the present work, 11 bioactive components of PVL were screened out, which acted on 177 potential targets. In addition, 13,517 genes were strongly associated with HCC pathogenesis, of which 158 targets are overlapped with PVL's targets. KEGG results identified 39 signaling pathways closely associated with the 158 targets. Molecular docking showed that the main bioactive components of PVL, kaempferol, morin, quercetin, luteolin, and spinasterol, had good binding activity with the core proteins in cancer biology such as AKT1, EGFR, SRC, ESR1, and PPARG. In vitro assays showed that quercetin, one of the main components of PVL extracts effectively inhibited HCC cell proliferation, and promoted apoptosis, which may be associated with PI3K/AKT signaling pathway. In summary, PVL may regulate HCC progression by regulating core targets such as AKT1, EGFR, SRC, ESR1, and PPARG, and acting on PI3K‐Akt signaling pathway. [ABSTRACT FROM AUTHOR]

Prevention of PM2.5 is attracting increasing attention all over the world as PM2.5 can cause and exacerbate respiratory diseases. Compared with conventional natural ventilation and mechanical ventilation, air purifiers with particular filters are more efficient in the control of indoor PM2.5. Currently, there are limited studies on the operations of portable indoor air purifiers. To improve the efficiency of an air purifier in control of PM2.5, an optimal operational strategy is needed. This paper proposes a framework for the optimization of operations of air purifiers for control of indoor PM2.5 based on building information modeling (BIM) and computational fluid dynamics (CFD). A case study is conducted to validate the proposed optimization framework and the results are discussed. It can be shown from the results that the best location of the air purifier can increase efficiency by up to 33% compared with other locations. [ABSTRACT FROM AUTHOR]

A large number of recent proofs indicate the irrationality of optimal resource allocation assumption in traditional economic growth theory, wherein resource misallocation (misallocation of capital and labor among heterogeneous enterprises) is regarded as the important reason for the difference in total factor productivity (TFP). In this article, we study resource allocation from the perspective of housing price, and measure the resource allocation efficiency of industrial enterprises in China based on industrial enterprises database covering the period of 1999–2007. We find that to some extent rising housing price has ameliorated resource allocation efficiency in China recently. We further find that rising housing price ameliorates resource allocation mainly in Central and Western areas and in labor-intensive industries. [ABSTRACT FROM AUTHOR]