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Adaptive Observer Based Backstepping Controller Design for Dynamic Ship Positioning

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China Ocean Engineering 2017年第5期31卷 639-645页

作者： DENG Fang WANG Long-jin jiao dong-mei College of Mechanical & Electrical Engineering Qingdao University of Science & Technology

Modified adaptive observer based backstepping control system for dynamic positioning of ship is proposed. As an improvement, the adaptive observer takes the first-order wave frequency model and the bias term which represent the slowly varying environmental disturbances and the unmodeled dynamics. Thus, the wave-frequency motions are filtered out, and only the reconstructed low-frequency motions are sent as inputs of the controller. Furthermore, as the ship dynamics parameters are unknown, the adaptive estimation law is designed for both the unknown ship dynamics and the unmeasured state variables. Based on the estimated states and parameters, backstepping controller considering the integral action is designed. Global exponential stability （GES） for the total system is proved using Lyapunov direct method. Simulation results show a good performance of the observer and control system.

关键词： Dynamic positioning backstepping control adaptive observer parameter estimation

A review on liquid metals as cathodes for molten salt/oxide electrolysis

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International Journal of Minerals,Metallurgy and Materials 2020年第12期27卷 1588-1598页

作者： Shu-qiang jiao Han-dong jiao Wei-li Song Ming-yong Wang Ji-guo TU State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Compared with solid metals,liquid metals are considered more promising cathodes for molten slat/oxide electrolysis due to their fascinating advantages,which include strong depolarization effect,strong alloying effect,excellent selective separation,and low operating *** this review,we briefly introduce the properties of the liquid metal cathodes and their selection rules,and then summarize development in liquid metal cathodes for molten salt electrolysis,specifically the extraction of Ti and separation of actinides and rare-earth metals in halide *** also review recent attractive progress in the preparation of liquid Ti alloys via molten oxide electrolysis by using liquid metal *** related to high-quality alloy production and large-scale applications are cited,and several research directions to further improve the quality of alloys are also discussed to realize the industrial applications of liquid metal cathodes.

关键词： liquid metal cathodes molten salts molten oxides electrolysis

HYDRODYNAMIC ANALYSIS OF SHORELINE OWC TYPE WAVE ENERGY CONVERTERS

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Journal of Hydrodynamics 2002年第1期14卷 8-15页

作者： Wang, dong-jiao Katory, Mahmoud Bakountouzis, Lambros Dept. of Naval Arch. and Ocean Eng. South China Univ. of Technol. Guangzhou 510640 China

A numerical model to predict the hydrodynamic performance of a shoreline-mounted wave energy converter, normally referred to as Oscillating Water Column (OWC), was established. Based on the 3D boundary integral equation method, the 3D Green's function was utilized to describe the hydrodynamic flow around the device. Using geometrical data of a wave absorber device symmetrically placed in a channel with various barrier depths, the hydrodynamic efficiencies were calculated for regular waves. The results were then compared with analytical results published elsewhere Malmo[8]. And the comparison is shown to be good, thus validating the proposed numerical model. Furthermore, extensive experiments were also made in a wave tank with a 1:12 scale model of an OWC device of different geometrical configurations. The experimental measurements were compared with calculations using the newly developed numerical model. The comparison, which is also shown to be satisfactory, provides further support of the correctness and the accuracy of the numerical method presented.

关键词： Hydrodynamics Mathematical models

Wire-like nano-polyaniline deposited electrochemically in a reverse micelle electrolyte as a p H sensor

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1115-1119页

作者： Fei Zhao Han-dong jiao Shi-qiang Zhao State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Wire-like polyaniline(PANI) films were successfully electrodeposited onto an indium tin oxide(ITO) substrate using a pulse galvanostatic method(PGM) in a reverse micelle electrolyte. The as-prepared PANI films were electrochemically analyzed by cyclic voltammetry and electrochemical impedance spectroscopy in 1 mol·L-1 HCl O4 solution. It is found that the as-prepared PANI films are highly porous, exhibit the diameters of approximately 100 nm and the lengths exceeding 3 μm, and have favorable electrochemical activities. Furthermore, the as-prepared wire-like PANI films show a good linear relationship of the potentiometric response curve over the p H value range of 3–10 with a slope of 74.13 m V·p H-1 in 0.5 mol·L-1 K2HPO4 basal solutions. The results demonstrate that the prepared wire-like PANI films are promising p H sensors.

关键词： electrodeposition polymers sensors thin films

Adaptive sliding-mode path following control system of the underactuated USV under the influence of ocean currents

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Journal of Systems Engineering and Electronics 2018年第6期29卷 1271-1283页

作者： CHEN Xiao LIU Zhong ZHANG Jianqiang ZHOU Dechao dong jiao School of Weaponry Engineering Naval University of Engineering

The path-following control of the asymmetry underactuated unmanned surface vehicle(USV) under external disturbances such as unknown constant and irrational ocean currents is discussed, and an adaptive sliding-mode path-following control system is proposed, which comprises a path-variable updated law,a modified integral line-of-sight(ILOS) guidance law based on a time-varying lookahead distance and adaptive feedback linearizing controllers combined with sliding-mode technique. A more accurate USV model without the assumption of having diagonal inertia and damping matrices is first presented, aiming at improving the performance of the path-following control. Next, the coordinate transformation is adopted to decouple the sway dynamic from the rudder angle, and the path-following errors dynamics without non-singular problem are presented in the moving Frenet-Serret frame. Then, based on the cascaded theorem and the adaptive sliding-mode method, the adaptive control law of position errors and course error are designed, among which the lookahead distance and integral gain are all computed as different functions of cross-track error to estimate and compensate the sideslip angle caused by external disturbances adaptively. Finally, according to the Lyapunov and cascaded theorem, the control system proposed is proved to be uniform globally asymptotic stability(UGAS) and uniform semiglobal exponential stability(USGES) when the control objectives are all achieved. Simulation results illustrate the precision and high-quality performance of this new controller.

关键词： sliding-mode control unmanned surface vehicle(USV) integral line-of-sight(ILOS) path following proof of stability

Density Functional Theory Study of Infrared and Ultraviolet Spectra of Urea L-Malic Acid

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Chinese Journal of Chemical Physics 2008年第6期21卷 535-540页

作者： Yan-lan Zhang Hong-yan Wang dong-sheng jiao Yong-hong Hu Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China College of Sciences Southwest Jiaotong University Chengdu 610031 China College of Life Science and Pharmaceutical Engineering Nanjing University of Technology Nanjing 210009 China

Urea L-malic acid, a new second order nonlinear optical crystal, was studied using density functional theory （DFT）. PBEPBE/6-31＋G（d,p） method, the optimal method for comparing the results from the several DFT methods, was chosen to study the molecular structure. Infrared and ultraviolet-visible spectra were obtained and compared with experiments. The ultraviolet-visible spectrum was also analyzed by the molecular orbital population. The geometries, and the infrared and ultraviolet-visible spectra in water were studied using DFT methods in combination with the polarized continuum model to predict the perturbations by the solvent effect.

关键词： Urea L-malic acid Density functional theory Molecular structure Infrared spectrum Ultraviolet-visible spectrum

Microstructural characteristics and mechanical properties of bobbin-tool friction stir welded 2024–T3 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 171-178页

作者： Ji-hong dong Chong Gao Yao Lu Jian Han Xiang-dong jiao Zhi-xiong Zhu Mechanical and Electrical Engineering Institute Beijing University of Chemical TechnologyBeijing 100089China China Friction Stir Welding Center Beijing Aeronautical Manufacturing Technology Research InstituteBeijing 100024China Chinalco Research Institute of Science and Technology Beijing 100082China School of Mechanical Materials and Mechatronic EngineeringUniversity of WollongongNew South Wales 2522Australia Research Centre of Joining Technology in Ocean Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China

Cold-rolled 2024-T3 sheet alloy was subjected to bobbin-tool friction stir welding （BTFSW）. The microstructural characteristics and mechanical properties of the nugget zone in the as-welded state were investigated. The results show that the equiaxed grain size of BTFSW 2024-T3 alloy decreases from 7.6 to 2.8 μm as the welding speed is increased from 80 to 120 mm/min; in addition, fine grains are generated in the nugget zone and the size distribution is non-uniform. All A12CuMg （S＇） precipitates dissolve into the A1 matrix, whereas Mn-rich phases confirmed as T phases （Al20CuEMn3, A16Mn, or AlaMn） remain unchanged. The optimized parameters for BTFSW are veri- fied as the rotation speed of 350 r/min and the travel speed of 100 mm/min. The variations in precipitation and dislocation play more impor- tant roles than grain size in the nugget zone with respect to influencing the mechanical properties during the BTFSW process. After the BTFSW process, the fracture mode of base material 2024-T3 alloy transforms from ductile rupture to ductile-brittle mixed fi＇acture.

关键词： aluminum alloys friction stir welding mechanical properties microstructure

Nanosheet-stacked flake graphite for high-performance Al storage in inorganic molten AlCl_(3)-NaCl salt

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International Journal of Minerals,Metallurgy and Materials 2020年第12期27卷 1711-1722页

作者： Jun-xiang Wang Ji-guo Tu Han-dong jiao d Hong-min Zhu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China Department of Metallurgy Graduate School of EngineeringTohoku UniversitySendaiMiyagi 9808579Japan

Aluminum storage systems with graphite cathode have been greatly promoting the development of state-of-the-art rechargeable aluminum batteries over the last five years;this is due to the ultra-stable cycling,high capacity,and good safety of the *** study discussed the change of electrochemical behaviors caused by the structural difference between flake graphite and expandable graphite,the effects of temperature on the electrochemical performance of graphite in low-cost AlCl_(3)-NaCl inorganic molten salt,and the reaction mechanisms of aluminum complex ions in both graphite materials by scanning electron microscopy,X-ray diffraction,Raman spectroscopy,cyclic voltammetry,and galvanostatic charge-discharge *** was found that flake graphite stacked with noticeably small and thin graphene nanosheets exhibited high capacity and fairly good rate *** battery could achieve a high capacity of^219 mA·h·g^(-1) over 1200 cycles at a high current density of 5 A·g^(-1),with Coulombic efficiency of 94.1%.Moreover,the reaction mechanisms are clarified:For the flake graphite with small and thin graphene nanosheets and high mesopore structures,the reaction mechanism consisted of not only the intercalation of AlCl4^-anions between graphene layers but also the adsorption of Al Cl4^-anions within mesopores;however,for the well-stacked and highly parallel layered large-size expandable graphite,the reaction mechanism mainly involved the intercalation of AlCl4^-anions.

关键词： flake graphite expandable graphite molten salts aluminum storage intercalation

New clinical trial design in precision medicine:discovery,development and direction

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1293-1321页

作者： Xiao-Peng Duan Bao-dong Qin Xiao-dong jiao Ke Liu Zhan Wang Yuan-Sheng Zang Department of Medical Oncology Changzheng HospitalNaval Medical UniversityShanghaiChina

In the era of precision medicine,it has been increasingly recognized that individuals with a certain disease are complex and different from each *** to the underestimation of the significant heterogeneity across participants in traditional"one-sizefits-all"trials,patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket,umbrella,and platform trial designs under the master protocol *** recent years,the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous *** the rapid increase in the number of basket,umbrella,and platform trials,the current clinical and research understanding of these new trial designs,as compared with traditional trial designs,remains *** majority of the research focuses on methodologies,and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial ***,we provide this comprehensive review of the discovery and development of basket,umbrella,and platform trials and their underlying logic from the perspective of precision ***,we discuss future directions on the potential development of these new clinical design in view of the"Precision Pro","Dynamic Precision",and"Intelligent Precision".This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic,which be essential to accelerate the progression of precision medicine.

关键词： clinical approval successive