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Toward Universal controller: Performance-Aware Self-Optimizing Reinforcement Learning for Discrete-Time Systems With Uncontrollable Factors

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IEEE Transactions on Systems, Man, and Cybernetics: Systems 2025年第5期55卷 3249-3260页

作者： Zhang, Jianfeng Zhang, Haoran Zhao, Chunhui Zhejiang University State Key Laboratory of Industrial Control Technology College of Control Science and Engineering Hangzhou310027 China

The industrial system usually contains not only controllable variables (CVs) but also uncontrollable variables (unCVs), e.g., weather conditions and friction. These unCVs have a direct impact on system control performance. Despite the success of current deep reinforcement learning (DRL) control algorithms, most of them neglect the impact of unCVs, which can cause the deterioration of control performance and instability of the system. To perceive and eliminate the impact of unCVs, a performance-aware self-optimizing universal controller (PASOUC) is designed in this article. The PASOUC aims at integrating the representation of unCVs and controller design to perceive and eliminate the impact of unCVs under different conditions, which goes beyond most existing control methods. Technically, a historical trajectory-inspired control performance perceptron is developed to perceive the impact of unCVs on system control performance under different conditions. Subsequently, a new performance-aware reward is designed to integrate the representation of unCVs and controller design while training the DRL controller. In addition, the domain randomization (DR) training strategy is employed to learn a universal control policy, which can access the approximate optimal trajectory under nonideal conditions. In this way, the impact of unCVs can be eliminated. To handle the low efficiency of the DR training, the policy improvement-policy proximal optimization (PI-PPO) is proposed to enhance the convergence speed of the DR training by performing explicit policy improvement. Finally, illustrative examples are presented to demonstrate the superiority of the proposed method. © 2013 IEEE.

关键词： Deep reinforcement learning

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Enhancement of Quality Factor in Gain-Assisted Acoustic Resonance Systems

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Acta Mechanica Solida Sinica 2025年第1期38卷 25-32页

作者： Lei Zhang Linlin Geng Yonghui Zhang Youdong Duan Jinbo Yuan Xiaoming Zhou Key Laboratory of Dynamics and Control of Flight Vehicle of Ministry of Education School of Aerospace EngineeringBeijing Institute of TechnologyBeijing100081China

Damped acoustic systems have a limited quality factor due to intrinsic *** introducing gain elements,a method to enhance the quality factor of damped systems is proposed based on the concept of bound states in the continuum(BICs).The acoustic model under study is a two-port waveguide system installed with two side Helmholtz resonators connected by a coupling *** on the temporal coupled-mode theory,a Hamiltonian matrix with both intrinsic and radiation losses is used to characterize the resonance behavior of the coupled *** achieve a high quality factor,acoustic gain is introduced to compensate the intrinsic loss,leading the Hamiltonian parameters toward a quasi-BIC *** simulation demonstrates a gain-assisted and quasi-BIC-supported extremely high quality factor in damped acoustic *** concept is further utilized to design a sensor model for particle size *** enhanced sensing performance due to high quality factors is numerically *** findings suggest potential applications in acoustic sensing and detection devices.

关键词： Acoustic resonance Quality factor Bound states in the continum Coupled-mode theory

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Internal solitary waves in the Shenhu continental shelf slope break zone of the northern South China Sea generate benthic storms

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Science China Earth Sciences 2025年第3期68卷 928-942页

作者： Yonggang JIA Xuezhi FENG Chaoqi ZHU Linsen WANG Xiaolei LIU Cong HU Hongwei WANG Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationOcean University of ChinaQingdao 266100China

Internal solitary waves can generate intense bottom currents and turbulent mixing over continental slopes, influencing the redistribution of sediments and pollutants, as well as driving changes in marine geomorphology and ecosystems. However,owing to the lack of detailed quantitative measurements of the bottom boundary layer, the mechanisms and impacts of internal solitary waves in resuspending and transporting seafloor sediments remain poorly understood. In this study, we present highresolution in situ observations of hydrodynamics in the upper layer(14–265 m) and the bottom boundary layer(<1 m) in the continental shelf slope break zone. Our results reveal that strongly nonlinear internal solitary waves, which occur at the peak of semidiurnal tidal currents, trigger benthic storms at the seafloor. Unlike previously proposed global instability mechanisms, the suspended sediment concentration caused by these strongly nonlinear internal solitary waves reaches 60 times higher than the background value and exhibits sudden, transient peaks. The bottom shear stress(τ) is an order of magnitude greater than that in laboratory measurements, and the observed fluctuating pressure is approximately 2.3 to 7 times greater than that in previous coastal observations. The sediments stirred by benthic storms are transported vertically to more than 100 m above the seabed,with lateral transport extending tens of kilometres beyond the study area. This process is driven by the dynamic mechanism of“strongly nonlinear internal solitary waves lifting sediments, weakly nonlinear internal solitary waves assisted by internal tides,and contour currents transporting sediments.” The suspended sediment flux induced by internal solitary waves in the South China Sea is on the same order of magnitude as that of global dust storm emissions, 21.9 times the volume of Asian dust storms entering the sea, and approximately 21 times the fluvial sediment flux entering the northern South China Sea. These find

关键词： Internal solitary waves Benthic storms Shear stress Suspended sediment flux Fluvial sediment flux

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Green disposal of waste smartphone protective film:Efficiency,mechanism,bench-scale test and secondary waste reutilization

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Journal of Environmental Sciences 2025年第5期151卷 692-702页

作者： Jiangyao Chen Shunyu Ding Chenxu Gao Canhui Chen Taicheng An Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

The manufacture and obsolescence of smartphones produce numerous waste plastic accessories(e.g.,waste smartphone protective film(WSPF)),possessing immense potential for ***,available recycling technologies have limitations such as substrate damage and secondary pollutant *** present study aimed to develop a green disposal method that not only recycled polyethylene terephthalate(PET)from WSPF,but also reused the stripped polyacrylate(PAA)adhesive as an adsorbent to reduce solid waste *** the WSPF was treated in 1 mol/L NaOH solution at 90°C,the PAA hydrolyzed to two main by-products of 1-butanol and 2-ethylhexanol,weakening the binding strength between PAA and PET and then efficient separation of *** bench-scale test revealed that over 97.2%of detachment efficiency toward PAA was achieved during continuous treatment of 17 batches of WSPF(200 g for each)without supplement of NaOH and generation of ***,the economic evaluation indicated that the recycling method would generate a net profit margin of 647%for the second year without considering the incurrence of new cost and ***,the pyrolysis of waste PAA enabled its conversion into potential adsorbent,which showed 2 to 4 times enhanced adsorption capacity toward styrene and ethyl acetate after modification with NaOH *** study provides a green method for recycling waste plastics and inspires a referable solution for solid waste treatment in the smartphone industry.

关键词： Smartphone accessory Waste protective film Green recycle Polyethylene terephthalate Polyacrylate Adsorbent

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Carbonyl-amine condensation coupled ozonolysis of dipropylamine and styrene:Decay kinetics,reaction mechanism,secondary organic aerosol formation and cytotoxicity

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Journal of Environmental Sciences 2025年第3期149卷 444-455页

作者： Wanying Li Jiangyao Chen Qinhao Lin Yuemeng Ji Taicheng An Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Oxidation of organic amines(OAs)or aromatic hydrocarbons(AHs)produces carbonyls,which further react with OAs to form carbonyl-amine condensation products,threatening environmental quality and human ***,there is still a lack of systematic understanding of the carbonyl-amine condensation reaction processes of OAs or between OAs and AHs,and subsequent environmental health *** work systematically investigated the carbonyl-amine condensation coupled ozonolysis kinetics,reaction mechanism,secondary organic aerosol(SOA)formation and cytotoxicity fromthe mixture of dipropylamine(DPA)and styrene(STY)by a combined method of productmass spectrometry identification,particle property analysis and cell exposure *** results from ozonolysis of DPA and STY mixture revealed that STY inhibited the ozonolysis of DPA to different degrees to accelerate its own decay *** barycenter of carbonyl-amine condensation reactionswas shifted from inside of DPA to between DPA and STY,which accelerated STY ozonolysis,but slowed down DPA *** the first time,ozonolysis of DPA and STY mixture to complex carbonyl-amine condensation products through the reactions of DPA with its carbonyl products,DPA with STY’s carbonyl products and DPA’s bond breakage product with STY’s carbonyl products was *** condensation products significantly contributed to the formation and growth of *** SOA containing particulate carbonyl-amine condensation products showed definite *** findings are helpful to deeply and comprehensively understand the transformation,fate and environmental health effects of mixed organics in atmospheric environment.

关键词： Organic amines(OAs) Aromatic hydrocarbons(AHs) Coupled ozonolysis Carbonyl-amine condensation Secondary pollution Toxicity assessment

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Research progress on secondary formation,photosensitive reaction mechanism and human health effects of chromophoric brown carbon

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Journal of Environmental Sciences 2025年第5期151卷 310-330页

作者： Baihang Chen Jiangyao Chen Guiying Li Taicheng An Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment Engineering Guangzhou Key Laboratory of Environmental Catalysis and Pollution ControlSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Brown carbon(BrC)has attracted widespread attention because of its strong absorption of solar radiation in the ultraviolet-visible wavelength range,which causes adverse impacts on human ***,BrC was a physically defined class of ***,current research has gradually shifted towards the identification of its chemical groups,because its light-absorbing capability,chemical properties and health effects mainly depend on the chemical composition of its ***,this review mainly focuses on the chemical understanding of BrC based on chromophores,and the secondary formation mechanism of chromophores,photosensitized reactions,and human health effects of BrC were detailly ***,BrC chromophores are divided into five categories:nitrogen-heterocycles,nitrogen-chain,aromatic species,oligomers and sulfur-containing organic *** chromophore precursor species exhibit variations,and their formation mechanisms are also ***,BrC can trigger the production of secondary organic aerosol(SOA)precursors or cause SOA growth because BrC is an important component of light-absorbing particles formed during incomplete combustion of biomass and fossil fuels,potentially exerting adverse effects on human ***,developing sufficiently separated methods for BrC and refining algorithms and machine learning can lead to a more effective understanding of the chemical composition of chromophores,thus enabling better evaluation of the atmospheric effects and health impacts of *** all,this review provides new insights into the categories of BrC chromophores and new advance in secondary formation mechanisms,photosensitized reactions,and human health effects on the basis of chemical structures.

关键词： Brown carbon Constituent characteristics Secondary formation mechanism Photosensitive Human health effects

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Deployment dynamics and experiments of a tendon-actuated flexible manipulator

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Chinese Journal of Aeronautics 2025年第2期38卷 459-477页

作者： Benteng ZHANG Jialiang SUN Haiyan HU State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China MOE Key Laboratory of Dynamics and Control of Flight Vehicle School of Aerospace EngineeringBeijing Institute of TechnologyBeijing 100081China

The quantity of space debris on Earth orbit has escalated tremendously in recent years, presenting a significant hazard to human space operations. It is urgent to develop effective measures to capture and remove various space debris. For this purpose, this paper presents a tendon-actuated flexible deployable manipulator. The flexible manipulator consists of several deployable units connected by Cardan joints and actuated by tendons. Compared with the present technologies for capturing space debris such as rigid robotic arm or flying net, this flexible manipulator is deployable, reusable, lightweight and applicable to the capture of large space debris. In order to investigate its deployment dynamics, an accurate dynamic model of the flexible manipulator is established based on the natural coordinate formulation (NCF) and the absolute nodal coordinate formulation (ANCF). Subsequently, numerical simulations are carried out to study the effects of system parameters and the base satellite on its deployment dynamics. Finally, ground experiments for both deployment and bending of the flexible manipulator are conducted to verify its effectiveness and feasibility.

关键词： Flexible manipulator Tendon-actuated Dynamic modeling Deployment dynamics Ground experiments

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A WKB method based on parabolic cylinder function for very-low-frequency sound propagation in deep ocean

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Chinese Physics B 2025年第3期34卷 433-446页

作者： Jian-Kang Zhan Sheng-Chun Piao Li-Jia Gong Yang Dong Yong-Chao Guo Guang-Xue Zheng National Key Laboratory of Underwater Acoustic Technology Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

A Wentzel-Kramers-Brillouin(WKB)method is introduced for obtaining a uniform asymptotic solution for underwater sound propagation at very low frequencies in deep *** method utilizes a mode sum and employs the reference functions method to describe the solution to the depth-separated wave equation approximately using parabolic cylinder *** conditions for the validity of this approximation are also ***,a formula that incorporates waveguide effects for the modal group velocity is derived,revealing that boundary effects at very low frequencies can have a significant impact on the propagation characteristics of even low-order normal *** present method not only offers improved accuracy compared to the classical WKB approximation and the uniform asymptotic approximation based on Airy functions,but also provides a wider range of depth ***,this method exhibits strong agreement with numerical methods and offers valuable physical ***,the method is applied to the study of very-low-frequency sound propagation in the South China Sea,leading to sound transmission loss predictions that closely align with experimental observations.

关键词： WKB method normal modes very-low-frequency sound propagation parabolic cylinder function

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Mechanical and electrochemical properties of(MoNbTaTiZr)1-xNx high-entropy nitride coatings

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材料科学技术（英文版） 2025年第5期208卷 78-91页

作者： Wei Yang Jianxiao Shen Zhenyu Wang Guanshui Ma Peiling Ke Aiying Wang Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

High-entropy materials possess high hardness and strong wear resistance,yet the key bottleneck for their practical applications is the poor corrosion resistance in harsh *** this work,the high-entropy nitride(HEN)coatings of(MoNbTaTiZr)1-xNx(x=0-0.47)were fabricated using a hybrid di-rect current magnetron sputtering *** research focus was dedicated to the effect of nitrogen content on the microstructure,mechanical and electrochemical *** results showed that the as-deposited coatings exhibited a typical body-centered cubic(BCC)structure without nitrogen,while the amorphous matrix with face-centered cubic(FCC)nanocrystalline grain was observed at x=*** increasing x in the range of 0.35-0.47 caused the appearance of polycrystalline FCC phase in *** with the MoNbTaTiZr metallic coating,the coating containing nitrogen favored the high hard-ness around 13.7-32.4 GPa,accompanied by excellent tolerance both against elastic and plastic ***,such N-containing coatings yielded a low corrosion current density of about 10-8-10-7 A/cm2 and high electrochemical impedance of 106 Ω cm2 in 3.5 wt.％NaCl solution,indicating the supe-rior corrosion *** reason for the enhanced electrochemical behavior could be ascribed to the spontaneous formation of protective passive layers over the coating surface,which consisted of the domi-nated multi-elemental oxides in chemical ***,noted that the(MoNbTaTiZr)0.83N0.17 coat-ing displayed the highest hardness of 32.4±2.6 GPa and H/E ratio at 0.09,together with remarkable cor-rosion resistance,proposing the strongest capability for harsh-environmental applications required both good anti-wear and anti-corrosion performance.

关键词： High-entropy nitride Magnetron sputtering Microstructure Mechanical property Corrosion behavior

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A comparison of the proto-dolomite induced by cyanobacteria and halophilic bacteria:implications for dolomite-inducing microbe identification

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Journal of Palaeogeography 2025年第1期14卷 277-290页

作者：赵延洋 Xiang-Yu Wei Xiao Gao Na Guo Jie Li Kai-Ming Hu Chao Han Qi-Yu Wang 韩作振 Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Science and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Key Laboratory of Sedimentary Basin and Oil and Gas Resources Ministry of Natural Resources Key Laboratory of Deep Oil and Gas China University of Petroleum

This study investigates the morphological and mineralogical characteristics of proto-dolomite induced by two specific microorganisms with varying lifestyles:the extremely halophilic bacterium Vibrio harveyi QPL2 and the cyanobacterium Leptolyngbya boryana. Halophilic bacterially-induced proto-dolomite(HBD) and cyanobacterially-induced proto-dolomite (CBD) were subjected to comprehensive characterization techniques, including X-ray diffraction, scanning electron microscopy, Focused Ion Beam, thermogravimetric analysis, and X-ray photoelectron spectroscopy. The results indicate that both HBD and CBD exhibit a low degree of crystallinity and possess comparable molar ratios of MgCO3to CaCO3. Moreover, neither of them exhibits the ordered structure of ideal dolomite. HBD and CBD exhibit notable distinctions in external morphology and internal structure. HBD forms a subunit aggregate with a less dense surface and numerous pinhole structures resulting from bacterial survival. In contrast, CBD adopts a bispherical shape with a relatively dense surface and minimal indications of cyanobacterial survival. Both HBD and CBD have an internal hollow structure. However, HBD is characterized by sparse population and loosely arranged subunits, while CBD features only a central cavity. Additionally, HBD particles are smaller compared to CBD particles. These morphological differences suggest that HBD primarily grows through bacterial surface-dependent processes,whereas the growth of CBD is not directly reliant on the surface of cyanobacteria. Compositionally, the weightpercentage of crystalline water in CBD exceeded that of HBD with a value of 29.42%compared to 5.9%. This increase in internal crystalline water enables a faster conversion of CBD to the ordered ideal dolomite in a specific diagenetic environment. This study implies that the morphology and composition of microbial protodolomite may aid in identifying the type of dolomite-inducing microbes.

关键词： Proto-dolomite Cyanobacteria Halophile Crystal morphology Water of crystallization

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