Tracking Control for a Quadrotor via Dynamic Surface Control and Adaptive Dynamic Programming

Qiang Gao,Xin-Tong Wei,Da-Hua Li,Yue-Hui Ji,Chao Jia 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.1

In this paper, a data-driven control algorithm based on the Dynamic Surface Control and the ActionDependent Heuristic Dynamic Programming is proposed to realize the stable tracking control of the quadrotor. Firstly, the dynamic surface control is addressed for the nonlinear model of the quadrotor, which can overcome the “explosion of complexity” problem encountered in traditional back-stepping method inevitably. The controller designed by Dynamic Surface Control is served as the main controller in the total control structure. Secondly, the Action-Dependent Heuristic Dynamic Programming is investigated to construct a complementary attitude controller by involving the learning mechanism. The adoption of Action-Dependent Heuristic Dynamic Programming can provide the capability of adaptation and disturbance rejection to improve the tracking control performance effectively. The overall closed-loop system is proved to be asymptotically stable by the Lyapunov theorem. Finally, the numerical simulation and flight experiments are presented to demonstrate that the proposed tracking control scheme exhibits an excellent tracking performance in the case of external disturbances.

Synthesis, Crystal Structure and Quantum Chemistry of a Novel Schiff Base N-(2,4-Dinitro-phenyl)-N'-(1-phenyl-ethylidene)-hydrazine

Ji, Ning-Ning,Shi, Zhi-Qiang,Zhao, Ren-Gao,Zheng, Ze-Bao,Li, Zhi-Feng Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.4

A novel Schiff base N-(2,4-dinitro-phenyl)-N'-(1-phenyl-ethylidene)-hydrazine has been synthesized and structurally characterized by X-ray single crystal diffraction, elemental analysis, IR spectra and UV-vis spectrum. The crystal belongs to monoclinic with space group P21/n. The molecules are connected via intermolecular O-$H{\cdots}O$ hydrogen bonds into 1D infinite chains. The crystal structure is consolidated by the intramolecular N-$H{\cdots}O$ hydrogen bonds. weak intermolecular C-$H{\cdots}O$ hydrogen bonds link the molecules into intriguing 3D framework. Furthermore, Density functional theory (DFT) calculations of the structure, stabilities, orbital energies, composition characteristics of some frontier molecular orbitals and Mulliken charge distributions of the title compound were performed by means of Gaussian 03W package and taking B3LYP/6-31G(d) basis set. The time-dependent DFT calculations have been employed to calculate the electronic spectrum of the title compound, and the UV-vis spectra has been discussed on this basis. The results show that DFT method at B3LYP/6-31G(d) level can well reproduce the structure of the title compound.

Overexpression of ENA1 from Yeast Increases Salt Tolerance in Arabidopsis

( Xiang Qiang Kong ),( Xiu Hua Gao ),( Wei Huan Li ),( Ji Qiang Zhao ),( Yan Xiu Zhao ),( Hui Zhang ) 한국식물학회 2008 Journal of Plant Biology Vol.51 No.2

In yeast, the plasma membrane Na+/H+ antiporter and Na+ -ATPase are key enzymes for salt tolerance. Saccharomyces cerevisiae Na+ -ATPase (Ena1p ATPase) is encoded by the ENA1/PMR2A gene; expression of ENA1 is tightly regulated by Na+ and depends on ambient pH. Although Ena1p is active mainly at alkaline pH values in S. cerevisiae, no Na+ -ATPase has been found in flowering plants. To test whether this yeast enzyme would improve salt tolerance in plants, we introduced ENA1 into Arabidopsis (cv. Columbia) under the control of the cauliflower mosaic virus 35S promoter. Transformants were selected for their ability to grow on a medium containing kanamyin. Southern blot analyses confirmed that ENA1 was transferred into the Arabidopsis genome and northern blot analyses showed that ENA1 was expressed in the transformants. Several transgenic homozygous lines and wild-type (WT) plants were evaluated for salt tolerance. No obvious morphological or developmental differences existed between the transgenic and WT plants in the absence of stress. However, overexpression of ENA1 in Arabidopsis improved seed germination rates and salt tolerance in seedlings. Under saline conditions, transgenic plants accumulated a lower amount of Na+ than did the wild type, and fresh and dry weights of the former were higher. Other experiments revealed that expression of ENA1 promoted salt tolerance in transgenic Arabidopsis under both acidic and alkaline conditions.

Distributed Containment Control for Multi-agent Systems in Purefeedback Form under Switching Topologies

Yuehui Ji,Hailaing Zhou,Qiang Gao 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.5

The distributed containment control problem is investigated for nonlinear multi-agent systems in purefeedback form subjected to switching directed communication topologies. Based on command filtered backstepping technology and singular-perturbation theorem, a containment controller is addressed to guarantee that the followers’ outputs can converge to the convex hull spanned by multi-dynamic leaders, and the containment tracking errors between leaders and followers is semi-global practical exponential stable in the closed-loop system. A nonlinear anti-tangent filter is adopted to estimate the virtual control, avoiding the analytical deduction inherent in traditional back-stepping method and overcoming the ?circular construction problem? in non-affine pure-feedback systems. Differing from the existing back-stepping method, the proposed control scheme only requires leaders’ output signals and their first derivative signals, does not need the prior knowledge of their nth order derivative signals. The stability analysis is completed via the singular perturbation theory, revealing some novel features of the underlying back-stepping method. Finally, two simulation examples are provided to illustrate the effectiveness of the control scheme.

Effects of α-Si₃N₄ seeds and sintering additives on properties of porous silicon nitride ceramics fabricated by carbothermal reduction

Yuan Lu,Ji-Qiang Gao,Jian-feng Yang 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.6

In this paper, porous Si3N4 ceramics were fabricated by carbothermal reduction between silicon dioxide and carbon [1]. The influences of α-Si3N4 seeds and sintering additives on the microstructure and mechanical properties of porous Si3N4 ceremics were investigated. XRD analysis proved the complete formation of a single-phase β-Si3N4. SEM analysis showed that the resultant porous Si3N4 ceramics had a fine microstructure and a uniform pore structure. The sintered sample with Lu2O3 as sintering additive showed finer, higher aspect ratio β-Si3N4 grains. The addition of Eu2O3 accelerated the densification of porous Si3N4 ceramics, decreased the porosity and increased the flexural strength. The addition of α-Si3N4 seeds accelerated the formation of the α-Si3N4 phase at a low temperature and the α-β phase transformation process at a high temperature. With an increase in the α-Si3N4 seeds content, the porosity decreased, and the flexural strength increased accordingly. In this paper, porous Si3N4 ceramics were fabricated by carbothermal reduction between silicon dioxide and carbon [1]. The influences of α-Si3N4 seeds and sintering additives on the microstructure and mechanical properties of porous Si3N4 ceremics were investigated. XRD analysis proved the complete formation of a single-phase β-Si3N4. SEM analysis showed that the resultant porous Si3N4 ceramics had a fine microstructure and a uniform pore structure. The sintered sample with Lu2O3 as sintering additive showed finer, higher aspect ratio β-Si3N4 grains. The addition of Eu2O3 accelerated the densification of porous Si3N4 ceramics, decreased the porosity and increased the flexural strength. The addition of α-Si3N4 seeds accelerated the formation of the α-Si3N4 phase at a low temperature and the α-β phase transformation process at a high temperature. With an increase in the α-Si3N4 seeds content, the porosity decreased, and the flexural strength increased accordingly.

Synthesis, Crystal Structure and Quantum Chemistry of a Novel Schiff Base N-(2,4-Dinitro-phenyl)-N'-(1-phenyl-ethylidene)-hydrazine

Ning-Ning Ji,Zhi-Qiang Shi,Ren-Gao Zhao,Ze-Bao Zheng,Zhi-Feng Li 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.4

A novel Schiff base N-(2,4-dinitro-phenyl)-N'-(1-phenyl-ethylidene)-hydrazine has been synthesized and structurally characterized by X-ray single crystal diffraction, elemental analysis, IR spectra and UV-vis spectrum. The crystal belongs to monoclinic with space group P21/n. The molecules are connected via intermolecular O-H···O hydrogen bonds into 1D infinite chains. The crystal structure is consolidated by the intramolecular N-H···O hydrogen bonds. weak intermolecular C-H···O hydrogen bonds link the molecules into intriguing 3D framework. Furthermore, Density functional theory (DFT) calculations of the structure, stabilities, orbital energies, composition characteristics of some frontier molecular orbitals and Mulliken charge distributions of the title compound were performed by means of Gaussian 03W package and taking B3LYP/6-31G(d) basis set. The time-dependent DFT calculations have been employed to calculate the electronic spectrum of the title compound, and the UV-vis spectra has been discussed on this basis. The results show that DFT method at B3LYP/6-31G(d) level can well reproduce the structure of the title compound.

Development of a New Duplex Real-Time Polymerase Chain Reaction Assay for Detection of Dicer in G. gallus

( Xiao Lin Ji ),( Qi Wang ),( Yu Long Gao ),( Yong Qiang Wang ),( Li Ting Qin ),( Xiao Le Qi ),( Hong Lei Gao ),( Xiao Mei Wang ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.5

Recently, there has been a growing body of evidence showing that cellular microRNAs (miRNAs) are involved in virus-host interactions. Numerous studies have focused on analyses of the expression profiles of cellular miRNAs, but the expression patterns of Dicer, which is responsible for the generation of miRNAs, have only rarely been explored in Gallus gallus. We developed a duplex realtime reverse transcriptase polymerase chain reaction (RTPCR) assay for the relative quantification of the mRNAs of Dicer and β-actin in G. gallus. To apply this method, the expression of Dicer in avian cells after infection with avian leukosis virus subgroup J (ALV-J) was detected using our established duplex real-time RT-PCR. The duplex realtime RT-PCR assay is sufficiently sensitive, specific, accurate, reproducible, and cost-effective for the detection of Dicer in G. gallus. Furthermore, this study, for the first time, demonstrated that ALV-J can induce differential expression of Dicer mRNA in the ALV-J-infected cells.

Processing, microstructure and mechanical properties of porous silicon nitride by a slip casting method using petroleum coke as pore former

Huan-Rui Wang,Ji-Qiang Gao,Fang-Li Yu,Yuan Li,Jian-Feng Yang 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.6

In this study, porous Si3N4 ceramics were obtained by a slip casting method which would be easier applied in industry. The most stable and dispersing aqueous suspension was obtained from a solid slurry content of 56.2%, a carboxymethyl cellulose concentration of 0.3% as the adhesive and 0.05% glycerol as the defoamer. Petroleum coke was used as pore-former, and at the same time, it was helpful for the stability of the suspension. The burning-out of the petroleum coke seemed to be an economical way for increasing the porosity of porous Si3N4. After sintering at 1,800℃ for 2 h, samples with a pore size about 10 μm, porosities of 45-60%, and flexural strength of 52.0-112.1MPa were obtained. In this study, porous Si3N4 ceramics were obtained by a slip casting method which would be easier applied in industry. The most stable and dispersing aqueous suspension was obtained from a solid slurry content of 56.2%, a carboxymethyl cellulose concentration of 0.3% as the adhesive and 0.05% glycerol as the defoamer. Petroleum coke was used as pore-former, and at the same time, it was helpful for the stability of the suspension. The burning-out of the petroleum coke seemed to be an economical way for increasing the porosity of porous Si3N4. After sintering at 1,800℃ for 2 h, samples with a pore size about 10 μm, porosities of 45-60%, and flexural strength of 52.0-112.1MPa were obtained.

Fabrication and properties of machinable SiC/h-BN Nano-composites

Hai-yun Jin,Nai-kui Gao,Zong-ren Peng,Guan-jun Qiao,Ji-qiang Gao 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.6

SiC/BN ceramic nano-composites powders were synthesized by an in-situ recation method and the composites were sintered by hot pressing in a N2 atmosphere. The microstructure, secondary phase and grain boundaries were characterized using a range of analytical techniques including TEM, SEM and XRD. The mechanical properties were determined, when the BN content is increaed because the nano-sized h-BN crystals were homogeneously dispersed around the SiC grains of the matrix, the fracture strength of the nano-composites decreased more slowly than that of the SiC/h-BN micro-composites, but the hardness of the composites decreased sharply and the machinability properites were improved noticeably. SiC/BN ceramic nano-composites powders were synthesized by an in-situ recation method and the composites were sintered by hot pressing in a N2 atmosphere. The microstructure, secondary phase and grain boundaries were characterized using a range of analytical techniques including TEM, SEM and XRD. The mechanical properties were determined, when the BN content is increaed because the nano-sized h-BN crystals were homogeneously dispersed around the SiC grains of the matrix, the fracture strength of the nano-composites decreased more slowly than that of the SiC/h-BN micro-composites, but the hardness of the composites decreased sharply and the machinability properites were improved noticeably.

Corrosion behavior and creepage discharze character for machinable AlN/h-BN ceramic composites

Hai-yun Jin,Bo He,Nai-kui Gao,Zong-ren Peng,Ji-qiang Gao 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.5

AlN particles coated with nano-BN were synthesized. The AlN/BN ceramic composites were sintered by Plasma Active Sintering (PAS). Because the nano-BN crystals were homogeneously dispersed around the AlN grains of the matrix, the chemical corrosion resistance of AlN/nano-sized h-BN ceramic composites was higher than that of AlN/micro-sized h-BN ceramic composites and monolithic AlN ceramics. Due to the better hydrophobic property of h-BN, the AlN/BN composites had a better hydrophobic property than the monolithic AlN ceramic, at the same time, because of the homogeneous dispersion of the nano-BN, the creepage discharze voltage of AlN/nano-sized BN composites was the highest. AlN particles coated with nano-BN were synthesized. The AlN/BN ceramic composites were sintered by Plasma Active Sintering (PAS). Because the nano-BN crystals were homogeneously dispersed around the AlN grains of the matrix, the chemical corrosion resistance of AlN/nano-sized h-BN ceramic composites was higher than that of AlN/micro-sized h-BN ceramic composites and monolithic AlN ceramics. Due to the better hydrophobic property of h-BN, the AlN/BN composites had a better hydrophobic property than the monolithic AlN ceramic, at the same time, because of the homogeneous dispersion of the nano-BN, the creepage discharze voltage of AlN/nano-sized BN composites was the highest.