Adaptive gain H∞ output feedback control strategy for horizontal vibration of highspeed elevator car system based on T-S fuzzy model

Ruijun Zhang,Tian Qiu,Chen Chen 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.2

An electric-liquid active guide shoe is designed to aim at the problem of car horizontal vibration caused by guide unevenness excitation. Considering the imprecision of system dynamic modeling caused by the change of load during high-speed elevator operation and the nonlinear factors of active guide shoe, the Takagi-Sugeno (T-S) fuzzy reasoning method is adopted to approximate the nonlinear car system model. Further, taking the car acceleration, displacement and actuator saturation as the controlled performance indexes, an adaptive gain H∞ output feedback control strategy is proposed based on the parallel distributed compensation rule (PDC) to attenuate the horizontal vibration of the car system. To illustrate the effectiveness of the controller and its robustness to load changes, the acceleration timefrequency response of 4 m/s high-speed elevator car system under light load and heavy load was analyzed, and compared with the numerical results under H2/H∞ robust control, It is further verified that the proposed H∞ output feedback controller with adaptive gain can effectively suppress the horizontal vibration of the high-speed elevator car system.

Wavelines : Visualization Method for Comparative Analysis of Time Series Data

Ruijun Liu,Ning Liu,Yi Chen,Yunfang Zhao,Yang Xu 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.9

Time series data has characteristics of huge differences among date values, non-continuity and long time span. Cloudlines layout algorithm can overcome the shortcoming of growing data over time, for the data is non-continuous, cyclical and greatly different in value, and the display is not ideal for space waste and form of a single attribute value data in Cloudline. In the thesis, we put forward the Cloudlines Map Visualization Analysis Methods according to the characteristics and shortcomings of time series data. The methods include data values using a logarithmic transformation, semi-ellipse superimposed waveform, transparency distinguishing the density, waveform smooth transition and unequal axes. The WaveLines diagram applied to pesticide residue data can help users

Interaction of Bilobalide and Ginkgolides B with Bovine Serum Albumin: A Fluorescence Quenching Study

Chen, Yan,Wang, Ruijun,Wang, Shusheng,Yang, Yi,Li, Shaofei,Kai, Guiqing Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.9

The interaction of bilobalide (BB) and ginkgolides B (GB) with bovine serum albumin (BSA) was investigated by fluorescent technique and UV/vis absorption spectroscopy. The results showed that BB and GB could intensively quench the fluorescence of BSA through a static quenching procedure. The binding constants (Ka) and the average binding distance between the donor (BSA) and the acceptor (ginkgolides) were obtained ($r_{BB}$ = 5.33 nm and $r_{GB}$ = 4.20 nm) by the theory of non-radiation energy transfer, and then the thermodynamic parameters such as ${\Delta}S^0$ (0.17-0.32 kJ/mol), ${\Delta}G^0$ (-20.76 ~ -17.79 kJ/mol) and ${\Delta}H^0$ (32.47-76.52 kJ/mol) could be calculated, respectively. All these results revealed that the interaction of BB and GB with BSA were driven mainly by hydrophobie force. The synchronous fluorescence spectroscopy was applied to examine the effect of two ginkgolides on the configuration of BSA. The configuration alteration of BSA could be induced by the hydrophobicitv environment of tyrosine with the increase of the drug concentration.

Response analysis of non-linear compound random vibration of a high-speed elevator

Ruijun Zhang,Chen Wang,Qing Zhang,Jie Liu 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.1

This study presents a non-linear constitutive equation for the rolling guide-shoes associated with a high-speed elevator system. This was done to accurately evaluate the dynamic behavior of a high-speed elevator car and analyze the action mechanism of random factors during manufacturing and installation on the dispersion of vibration acceleration. Through the combination of the Hertz contact theory and the Bouc-Wen hysteretic model, the non-linear vibration model of the elevator car system was founded. This model was equivalent to a linear system by least squares technique, and then the random parameters and the random excitation were converted by random perturbation method and pseudo excitation method. The acceleration response sensitivities of each random parameters, the means and standard deviations of transverse vibration acceleration responses at the observation point were obtained. In the case, the transverse vibration acceleration responses of the car system were calculated. The elevator car’s vibration instance was analyzed under the different degrees of variation of the random parameters and the random excitation. The results showed that the randomness of geometric parameters has the greatest influence on transverse acceleration. The variability of parameters affects the dispersion degree of the transverse vibration responses while the variability of the excitation mainly affects the amplitude of the vibration response. This study provides an effective method for the analysis of non-linear compound random vibration responses of high-speed elevator car system, and provides a reference for the vibration control design and safety assessment.

Interaction of Bilobalide and Ginkgolides B with Bovine Serum Albumin: A Fluorescence Quenching Study

Yan Chen,Guiqing Kai,Shaofei Li,Yi Yang,Shusheng Wang,Ruijun Wang 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.9

The interaction of bilobalide (BB) and ginkgolides B (GB) with bovine serum albumin (BSA) was investigated by fluorescent technique and UV/vis absorption spectroscopy. The results showed that BB and GB could intensively quench the fluorescence of BSA through a static quenching procedure. The binding constants (Ka)and the average binding distance between the donor (BSA) and the acceptor (ginkgolides) were obtained (r_(BB)= 5.33 nm and rGB = 4.20 nm) by the theory of non-radiation energy transfer, and then the thermodynamic parameters such as ΔS^0 (0.17-0.32 kJ/mol), ΔG^0 (-20.76 ~ -17.79 kJ/mol) and ΔH^0 (32.47-76.52 kJ/mol) could be calculated, respectively. All these results revealed that the interaction of BB and GB with BSA were driven mainly by hydrophobie force. The synchronous fluorescence spectroscopy was applied to examine the effect of two ginkgolides on the configuration of BSA. The configuration alteration of BSA could be induced by the hydrophobicitv environment of tyrosine with the increase of the drug concentration.

Effect of Dextran Gel on Preparation of Nano-liposomes Loaded with Ginkgolide

Tong, Yuan,Chen, Yan,Pan, Jian,Huang, Li,Wang, Ruijun Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.9

The objective of this paper was to investigate the effect of dextran gel on preparation of nano-liposomes loaded with ginkgolide. During preparation, Sephadex G75, G50 and G25 were added in the aqueous phase respectively. From the experiment, nano-liposomes prepared by dextran gels were found spherical and smooth. The result indicated that aperture of dextran gels were narrower, particle size of nano-liposomes was smaller (207.13 ~ 89.16 nm) and zeta potential was greater (-36.2 ~ -29.5 mV) in more negative. The study also revealed that differences of the entrapment efficiency and drug loading among the three types of nano-liposomes were not significant. In vitro drug release test demonstrated that nano-liposomes had a better controlled release. To conclude, by using dextran gel in the preparation of nano-liposome loaded with ginkgolide, the particle size could be effectively controlled and the drug stability could be improved.

Preparation of CdSe QDs-carbohydrate Conjugation and its Application for HepG2 Cells Labeling

Jiang, Mingxing,Chen, Yan,Kai, Guiqing,Wang, Ruijun,Cui, Huali,Hu, Meili Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.2

In present study, CdSe quantum dots (QDs) were prepared with a novel but simple, effective and exercisable method. Nine different types of carbohydrate molecules were used to modify CdSe QDs. D-mannose (Man)-coated quantum dots were prepared for labeling human hepatoma (HepG2) cells, because of the high expression of mannose receptor (MR) on HepG2 cells. The uptake characteristics of CdSe QDs-Man were investigated in HepG2 cells. The absorption rate result of MTT assay in 48 h suggested the extremely low cytotoxicity of CdSe QDs-Man. The presence of quantum dots was confirmed with fluorescence microscopy. These results were encouraging regarding the application of QDs molecules for early detection of HepG2 cells.

Preparation of CdSe QDs-carbohydrate Conjugation and its Application for HepG2 Cells Labeling

Mingxing Jiang,Yan Chen,Guiqing Kai,Ruijun Wang,Huali Cui,Meili Hu 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.2

In present study, CdSe quantum dots (QDs) were prepared with a novel but simple, effective and exercisable method. Nine different types of carbohydrate molecules were used to modify CdSe QDs. D-mannose (Man)-coated quantum dots were prepared for labeling human hepatoma (HepG2) cells, because of the high expression of mannose receptor (MR) on HepG2 cells. The uptake characteristics of CdSe QDs-Man were investigated in HepG2 cells. The absorption rate result of MTT assay in 48 h suggested the extremely low cytotoxicity of CdSe QDs-Man. The presence of quantum dots was confirmed with fluorescence microscopy. These results were encouraging regarding the application of QDs molecules for early detection of HepG2 cells.

Effect of Dextran Gel on Preparation of Nano-liposomes Loaded with Ginkgolide

Yuan Tong,Yan Chen,Jian Pan,Li Huang,Ruijun Wang 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.9

The objective of this paper was to investigate the effect of dextran gel on preparation of nano-liposomes loaded with ginkgolide. During preparation, Sephadex G75, G50 and G25 were added in the aqueous phase respectively. From the experiment,nano-liposomes prepared by dextran gels were found spherical and smooth. The result indicated that aperture of dextran gels were narrower, particle size of nano-liposomes was smaller (207.13 ~ 89.16 nm) and zeta potential was greater (‒36.2 ~ ‒29.5 mV) in more negative. The study also revealed that differences of the entrapment efficiency and drug loading among the three types of nano-liposomes were not significant. In vitro drug release test demonstrated that nano-liposomes had a better controlled release. To conclude, by using dextran gel in the preparation of nano-liposome loaded with ginkgolide, the particle size could be effectively controlled and the drug stability could be improved.

Ginsenoside Rg1 ameliorates Alzheimer's disease pathology via restoring mitophagy

Ni Wang,Junyan Yang,Ruijun Chen,Yunyun Liu,Shunjie Liu,Yining Pan,Qingfeng Lei,Yuzhou Wang,Lu He,Youqiang Song,Zhong Li The Korean Society of Ginseng 2023 Journal of Ginseng Research Vol.47 No.3

Background: Alzheimer's disease (AD) is a common form of dementia, and impaired mitophagy is a hallmark of AD. Mitophagy is mitochondrial-specific autophagy. Ginsenosides from Ginseng involve in autophagy in cancer. Ginsenoside Rg1 (Rg1 hereafter), a single compound of Ginseng, has neuroprotective effects on AD. However, few studies have reported whether Rg1 can ameliorate AD pathology by regulating mitophagy. Methods: Human SH-SY5Y cell and a 5XFAD mouse model were used to investigate the effects of Rg1. Rg1 (1µM) was added to β-amyloid oligomer (AβO)-induced or APPswe-overexpressed cell models for 24 hours. 5XFAD mouse models were intraperitoneally injected with Rg1 (10 mg/kg/d) for 30 days. Expression levels of mitophagy-related markers were analyzed by western blot and immunofluorescent staining. Cognitive function was assessed by Morris water maze. Mitophagic events were observed using transmission electron microscopy, western blot, and immunofluorescent staining from mouse hippocampus. The activation of the PINK1/Parkin pathway was examined using an immunoprecipitation assay. Results: Rg1 could restore mitophagy and ameliorate memory deficits in the AD cellular and/or mouse model through the PINK1-Parkin pathway. Moreover, Rg1 might induce microglial phagocytosis to reduce β-amyloid (Aβ) deposits in the hippocampus of AD mice. Conclusion: Our studies demonstrate the neuroprotective mechanism of ginsenoside Rg1 in AD models. Rg1 induces PINK-Parkin mediated mitophagy and ameliorates memory deficits in 5XFAD mouse models.