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An Online Q-Learning Method for Linear-Quadratic Nonzero-Sum Stochastic Differential Games with Completely Unknown Dynamics

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Journal of Systems Science & Complexity 2024年第5期37卷 1907-1922页

作者： ZHANG bao-Qiang WANG Bing-Chang cao Ying School of Control Science and Engineering Shandong UniversityJinan 250000China

In this paper,the authors design a reinforcement learning algorithm to solve the adaptive linear-quadratic stochastic n-players non-zero sum differential game with completely unknown *** each player,a critic network is used to estimate the Q-function,and an actor network is used to estimate the control input.A model-free online Q-learning algorithm is obtained for solving this kind of *** is proved that under some mild conditions the system state and weight estimation errors can be uniformly ultimately bounded.A simulation with five players is given to verify the effectiveness of the algorithm.

关键词： Actor-critic algorithm model-free adaptive control nonzero-sum stochastic game reinforcement learning

Force-position collaborative optimization of rope-driven snake manipulator for capturing non-cooperative space targets

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Chinese Journal of Aeronautics 2024年第9期37卷 369-384页

作者： Xiaofeng LI Jian TIAN cheng WEI Xibin cao School of Astronautics Harbin Institute of TechnologyHarbin 150001China Beijing Instiuteof Spacecraft System Engineering China Academy of Space TechnolgyBeijing 100094Chia

With the rapid development of space activities,non-cooperative space targets increase swiftly,such as failed satellites and upper stages,threating normal spacecrafts *** there are some problems in the capture process,such as excessive collision and fast tumbling of targets,manipulator with redundant Degrees of Freedom(DOFs)can be used to improve the compliance and therefore solve these *** Rope-Driven Snake Manipulator(RDSM)is a combina-tion of hyper-redundant DOFs and better compliance,and therefore it is suitable for capturing *** this paper,a snake manipulator mechanism is designed,and the complete kinematic model and system dynamic model considering RDSM,target and contact is ***,to obtain the configuration of joint with hyper-redundant DOFs,an improved motion dexterity index is pro-posed as the joint motion optimization ***,the force-position collaborative optimization index is designed to adjust active stiffness,and the impedance control method based on the modified index is used to capture the space ***,the proposed force-position collaborative opti-mization method is verified by virtual prototype *** results demonstrate that based on the proposed method,the collision force is reduced by about 25%compared to normal impe-dance control,showing higher safety.

关键词： Capturing non-cooperative spacetargets Rope-driven snakemanipu-lator Force-position collaborative optimization Redundant degrees of free-dom Active stiffness adjustment

Effect of Active–Passive Deformation on the Thrust by the Pectoral Fins of Bionic Manta Robot

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Journal of Bionic Engineering 2024年第2期21卷 718-728页

作者： Yang Lu Shaomin Meng cheng Xing Yiwei Hao Yonghui cao Guang Pan Yong cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo315103China State Key Lab of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou310027China Zhejiang Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringZhejiang UniversityHangzhou310027China

Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient *** manta wings’deformation is evident during the swimming *** improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is *** this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)*** APD fin was actively controlled by two servo motors and could be passively deformed to variable *** APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of *** results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan *** average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral *** obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).

关键词： Manta ray Bionic pectoral fin Fin Ray®effect Active-passive deformation(APD)

Effects of hydrogen-rich saline on platelet activation in hypertensive rats

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中国药理学与毒理学杂志 2016年第10期30卷 1006-1007页

作者： HE Ke-gui WANG Yun MIN Xiang-dong HAN Ji-ju JIAO Peng CHEN Xiu-yu cao cheng-bao GONG Min ZHAO Xiao-min Institute of Pharmacology Taishan Medical University Department of Clinical Pharmacy Ningyang County People's Hospital Institute of Atherosclerosis Taishan Medical University Department of Laboratory Management Taishan Medical University

OBJECTIVE To investigate the effect of hydrogen-rich saline on platelet activation in hypertensive *** The male Wistar rats were divided into control group,hypertension group,control+hydrogen-rich saline group and hypertension+hydrogen-rich saline *** was induced by subcutaneous infusion with angiotensinⅡ0.7 mg·kg-1·d-1for 2 weeks by osmotic mini-pumps in ***-rich saline(10 mL·kg-1·d-1)was administered by intraperitoneal injection for 14 *** adhesion on collagen surface was evaluated using a well-defined perfusion chamber at low shear rate(300s-1)and high shear rate(1080s-1).The maximum aggregation rate of platelets induced by ADP was determined by *** levels of reactive oxygen species(ROS),nitric oxide(NO)and Ca2+in platelets were measured with flow *** When compared with the control group,platelet aggregation,platelet adhesion rate in high shear rate and low shear rate,and the level of ROS and Ca2+in platelets were elevated in hypertensive ***,NO level in platelets *** with the hypertensive group,hydrogen-rich saline treatment decreased platelet aggregation,platelet adhesion rate,the levels of ROS and Ca2+in platelets,and increased NO level in platelets of hypertensive *** Hydrogen-rich saline could inhibit platelet activation in hypertensive *** effect may be related to antioxidative stress.

关键词： hypertension platelet activation hydrogen oxidative stress

CO2-facilitated upcycling of polyolefin plastics to aromatics at low temperature

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National Science Review 2024年第05期11卷 236-243页

作者： Yi Ding Shuchi Zhang cheng Liu Yu Shao Xiulian Pan Xinhe bao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemical Physics University of Science and Technology of China

Plastics are one of the most produced synthetic materials and largest commodities, used in numerous sectors of human life. To upcycle waste plastics into value-added chemicals is a global challenge. Despite significant progress in pyrolysis and hydrocracking, which mainly leads to the formation of pyrolysis oil,catalytic upcycling to value-added aromatics, including benzene, toluene and xylene（BTX）, in one step, is still limited by high reaction temperatures（>500°C） and a low yield. We report herein CO2-facilitated upcycling of polyolefins and their plastic products to aromatics below 300°C, enabled by a bifunctional Pt/Mn Ox-ZSM-5 catalyst. ZSM-5 catalyzes cracking of polyolefins and aromatization, generating hydrogen at the same time, while Pt/Mn Ox catalyzes the reaction of hydrogen with CO2, consequently driving the reaction towards aromatization. Isotope experiments reveal that 0.2 kg CO2is consumed per 1.0 kg polyethylene and 90% of the consumed CO2is incorporated into the aromatic products. Furthermore, this new process yields 0.63 kg aromatics（BTX accounting for 60%）, comparing favorably with the conventional pyrolysis or hydrocracking processes, which produce only 0.33 kg aromatics. In this way, both plastic waste and the greenhouse gas CO2are turned into carbon resources, providing a new strategy for combined waste plastics upcycling and carbon dioxide utilization.

关键词： polyolefins carbon dioxide aromatics upcycling bifunctional catalysis

Simultaneous control of ferromagnetism and ferroelasticity by oxygen octahedral backbone stretching

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Chinese Physics B 2024年第9期33卷 186-192页

作者： Genhao Liang Hui cao Long cheng Junkun Zha Mingrui bao Fei Ye Hua Zhou Aidi Zhao Xiaofang Zhai Department of Physics University of Science and Technology of ChinaHefei 230026China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Materials Science Division Argonne National LaboratoryLemontIL 60439USA X-ray Science Division Advanced Photon SourceArgonne National LaboratoryLemontIL 60439USA

Coexistence of ferromagnetism and ferroelasticity in a single material is an intriguing phenomenon,but has been rarely *** we studied both the ferromagnetism and ferroelasticity in a group of LaCoO3 films with systematically tuned atomic *** found that all films exhibit ferroelastic domains with four-fold symmetry and the larger domain size(higher elasticity)is always accompanied by stronger *** performed synchrotron x-ray diffraction studies to investigate the backbone structure of the CoO6 octahedra,and found that both the ferromagnetism and the elasticity are simultaneously enhanced when the in-plane Co–O–Co bond angles are *** the study demonstrates the inextricable correlation between the ferromagnetism and ferroelasticity mediated through the octahedral backbone structure,which may open up new possibilities to develop multifunctional materials.

关键词： perovskite oxide film ferromagnetism ferroelasticity twin domain

Sustainable production of high-energy-density jet fuel via cycloaddition reactions

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Journal of Energy Chemistry 2024年第8期95卷 712-722,I0016页

作者： Yan-cheng Hu Yingying Zhao Ning Li Jing-Pei cao School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou 221116JiangsuChina School of Education Science Jiangsu Normal UniversityXuzhou 221116JiangsuChina CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Developing an energy supply-chain based on renewable biomass holds great potential to build a low carbon ***-energy-density(HED)jet fuel,featuring unique fused/strained cycloalkanes,is of great significance for volume-limited military aircrafts,as their high density and combustion heat can extend flight duration and increase the ***,the exploration of biomass-based routes towards HED fuel has drawn much attention over the past *** reaction features rapid construction of various carbocycles in an atom-and step-economical *** elegant strategy has been widely applied in the manufacture of sustainable HED *** we carefully summarize the progress achieved in this fascinating area and the review is categorized by the cycloaddition patterns including[4+2],[2+2],[4+4],and[2+1]***,the energy densities of the as-prepared biofuels and petroleumbased fuels(conventional Jet-A and advanced JP-10)are also *** review will provide important insights into rational design of new HED fuel with different ring-types/sizes and inspire the chemists to turn those literature studies into practical applications in military field.

关键词： High-energy-density fuel Biomass-based chemicals Cycloaddition Cycloalkanes Catalysis

Preparation of Flower-like Copper Foam Supported Co_(3)O_(4) Electrocatalyst and Its Hydrogen Evolution Performance

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 327-331页

作者：李兆 cheng Julong WANG Yanan WU Kunyao cao Jing School of Materials Engineering Xi’an Aeronautical InstituteXian 710077China

Flower-like copper foam Co_(3)O_(4) catalysts(Co_(3)O_(4)/CF) were prepared by hydrothermal *** crystalline structure and microscopic morphology of the prepared samples were characterized by using X-ray diffractometer(XRD) and scanning electron microscope(SEM),and the electrochemical properties were investigated by an electrochemical *** experimental results show that the Co_(3)O_(4) catalysts are successfully prepared on the foamed copper support by hydrothermal method,and the material’s morphology is mainly flower *** the current density is 10 mA·cm^(-2),the overpotential value of the Co_(3)O_(4)/CF catalyst is 141 mV,lower than that of blank *** electrochemical impedance(EIS) spectrum shows that the R_(ct )value of the Co_(3)O_(4)/CF catalyst decreases,and the Coulomb curves of double-layer show that the electrochemically active area of the Co_(3)O_(4)/CF catalyst efficiently increases compared with that of the blank ***,the as-obtained Co_(3)O_(4)/CF catalyst exhibits a good hydrogen evolution rate,showing great applicability potential in the catalytic electrolysis of water for hydrogen production.

关键词： Co_(3)O_(4)/CF composite structure electrocatalysis hydrogen evolution reaction

Assembly of peptide nanostructures with controllable sizes

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Nano Research 2024年第1期17卷 151-161页

作者： Dan cheng Fan Jia Yun-bao Jiang Vincent P.Conticello Tao Jiang The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Department of Chemistry Emory UniversityAtlanta 30033USA

Controlled peptide assembly offers significant promise to develop synthetic supramolecular nanostructures to display material and biological properties that mimic protein assemblies in *** the progress in forming peptide nanostructures of various morphology,there exists a distinct gap between natural and synthetic assembly systems in terms of size *** nanostructures with a narrow size distribution that can be tuned over a wide range of length-scales is essential for applications that require precise spacing between *** approach provides the opportunity to correlate materials and biological properties of interest with assembly *** this review,we discuss representative endeavors over the past two decades for design of size-controllable peptide nanostructures using tunable building *** mechanisms for size control,e.g.,molecular frustration,template-directed peptide assembly,and multi-component peptide co-assembly,will also be *** also demonstrate the applicable scopes of these strategies and suggest potential future avenues for scientific advances in this field.

关键词： peptide assembly controllable size template multi-component