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Event-triggered H_(∞) consensus control for input-constrained multi-agent systems via reinforcement learning

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Control Theory and Technology 2024年第1期22卷 25-38页

作者： Jinxuan Zhang Chang-E ren College of Information Engineering Capital Normal UniversityBeijing100089China

This article presents an event-triggered H_(∞) consensus control scheme using reinforcement learning (RL) for nonlinear second-order multi-agent systems (MASs) with control constraints. First, considering control constraints, the constrained H_(∞) consensus problem is transformed into a multi-player zero-sum game with non-quadratic performance functions. Then, an event-triggered control method is presented to conserve communication resources and a new triggering condition is developed for each agent to make the triggering threshold independent of the disturbance attenuation level. To derive the optimal controller that can minimize the cost function in the case of worst disturbance, a constrained Hamilton–Jacobi–Bellman (HJB) equation is defined. Since it is difficult to solve analytically due to its strongly non-linearity, reinforcement learning (RL) is implemented to obtain the optimal controller. In specific, the optimal performance function and the worst-case disturbance are approximated by a time-triggered critic network;meanwhile, the optimal controller is approximated by event-triggered actor network. After that, Lyapunov analysis is utilized to prove the uniformly ultimately bounded (UUB) stability of the system and that the network weight errors are UUB. Finally, a simulation example is utilized to demonstrate the effectiveness of the control strategy provided.

关键词： H_(∞)optimal control Input constrains Multi-agent systems(MASs) Reinforcement learning(RL)

Finite-size-induced non-Hermitian phase transitions in real space

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 105-111页

作者： Hongfei Wang Biye Xie Wei ren Department of Physics International Center for Quantum and Molecular StructuresShanghai UniversityShanghai 200444China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

While non-Hermiticity provokes intriguing phenomena without Hermitian counterparts, e.g., the skin effect and the breakdown of bulk-boundary correspondence, attracting extensive attention both in fundamental physics and device engineering, the role of finite sizes therein remains elusive. Here, we propose a class of finite-size-induced non-Hermitian phase transitions, relying upon higher-order topological invariants associated with real-space wave functions. The phase diagrams for general non-Hermitian chiral models are further acquired to demonstrate our topological definition. Such phase transitions are elucidated qualitatively by an effective intercell coupling alteration that depends on finite sizes in respective directions. Besides, we mimic these phenomena by analogizing the circuit Laplacian in finite-size electric circuits with nonreciprocal couplings. The resultant admittance spectra agree with our theoretical predictions. Our findings shed light on the finite-size mechanism of non-Hermitian topological phase transitions and pave the way for applications in switching and sensing.

关键词： non-Hermitian phase transitions finite-size effects higher-order topological invariants

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Recent progress in single crystal perovskite X-ray detectors

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Science China(Information Sciences) 2024年第3期67卷 5-19页

作者： Xiao LIU Jun ren Yu-Ang CHEN Xiangshun GENG Dan XIE Tian-Ling ren School of Integrated Circuits Tsinghua University Beijing National Research Center for Information Science and Technology (BNRist)

Perovskites have attracted extensive attention as radiation detection material due to their long carrier diffusion length and lifetime, high absorption coefficient, and flexible manufacturing process. Compared with polycrystalline structures, single crystal perovskites improve the performance of optoelectronic devices due to their low defect state density, better photoelectric characteristics, and chemical ***, we review the recent progress of single crystal perovskite X-ray detectors. First, we briefly introduced the basic concepts, detection mechanisms, figure of merits of perovskite X-ray detectors, and the preparation methods of single crystal perovskites. Then, we summarized the significant advancements in single crystal perovskite X-ray detectors in recent times. Finally, we discussed the critical challenges and some practicable solutions for developing high-performance X-ray detectors.

关键词： single crystal perovskites carrier transport radiation detection X-ray detectors X-ray imaging

Boundary-lubricated biomaterials with drug delivery for osteoarthritis treatment

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Friction 2024年第10期12卷 2167-2187页

作者： Junyu WU Kaixuan ren Jingbo YIN Department of Polymer Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The good lubrication ability of articular cartilage holds significant importance in our daily ***(OA),the most prevalent degenerative joint disease,causes cartilage damage,increased friction,and ***,the current clinical treatments for OA exhibit some ***,the sustained drug release systems with lubricating function have attracted considerable attention for treating *** review introduces the lubrication mechanism of cartilage,focusing particularly on the boundary lubrication *** research progress of boundary-lubricated biomaterials with drug delivery,including microcarriers,hydrogels,and nanoparticles in the treatment of OA by improving inter-articular lubrication and relieving inflammation is discussed and *** efficacy and challenges of boundary-lubricated biomaterials with drug delivery in the treatment of OA are summarized,and the prospects are also discussed.

关键词： osteoarthritis joint friction boundary lubrication hydration lubrication drug delivery

An effective bimetallic oxide catalyst of RuO_(2)-Co_(3)O_(4) for alkaline overall water splitting

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Nano Research 2024年第5期17卷 3785-3793页

作者： Fangfang ren Jiayu Xu Ligang Feng College of Chemical and Environmental Engineering Yancheng Teachers UniversityYancheng 224007China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

The rational design of effective bifunctional electrocatalysts is of paramount importance for overall water-splitting technology in sustainable energy ***,bimetallic oxide catalysts(RuO_(2)-Co_(3)O_(4))derived from Ru combined MOF-derivatives(MOF=metal-organic framework)were demonstrated effective for overall water splitting in an alkaline solution,owing to the combined merits such as the two-dimensional interconnected network structure,the synergetic coupling effects and increased chemical *** as-prepared RuO_(2)-Co_(3)O_(4) only requires an overpotential of 260 mV for oxygen evolution and 75 mV for hydrogen evolution at 10 mA/cm^(2) in 1 M KOH solution;a low cell voltage of 1.54 V was required to reach the kinetic current density of 10 mA/cm^(2) for the water electrolysis when supporting on glass carbon electrode,and very good stability for 40 h was *** and theoretical results demonstrated the electronic structure optimization of bimetallic RuO_(2)-Co_(3)O_(4) compared to the individual metal oxide,which promoted interface charges redistribution and the d-band center downshift,resulting in increased activity and stability for water-splitting *** work provides a feasible approach for developing bimetallic oxides for application in energy-relevant electrocatalysis reactions.

关键词： ruthenium dioxide cobalt oxide metal-organic frameworks heterostructures overall water splitting

Doping-reinforced interfacial electric field for charge oriented accumulation in Ohm junction boosting photocatalytic Nfixation

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Science China Chemistry 2024年

作者： Hua Wen Ruqi Li Jingyu ren Razium Ali Soomro Shoujian fu Li Guo Feng fu Bin Xu Chunming Yang Danjun Wang College of Chemistry and Chemical Engineering Yan'an University Shaanxi Key Laboratory of Chemical Reaction Engineering

The interfacial electric field （IEF） determines the charge carriers transport and the reactivity of heterostructure ***,the restricted IEF lead to inefficient interfacial charge transport and oriented accumulation,resulting in low photocatalytic ***,a interfacial chemical-bonded Ti-BiOBr/1T-MoS1.85Ohm junction is fabricated via electrostatic self-assembly strategy,in which Ti doping precisely regulates the local electrical structure and work function of BiOBr,thus boosting the IEF to efficiently drive charge transfer and oriented accumulation to active *** femtosecond transient absorption spectroscopy verified that the Ti0.1Bi0.9OBr/1T-MoS1.85-6%increased the shallow electron trapping （τ1=0.57 ps）while the depressed recombination of photoinduced electrons with trapped holes （τ2=71.88 ps） compared to the BiOBr/1T-MoS1.85-6%（τ1=0.78 ps,τ2=54.61 ps）.More Importantly,the interfacial charge carriers transfer from Ti0.1Bi0.9OBr to 1T-MoS1.85（τ3=86.53 ps） was significantly accelerated by the reinforced IEF compared to BiOBr/1T-MoS1.85-6%（τ3=221.51 ps）.The N2-to-NH3conversion rate of Ti0.1Bi0.9OBr/1T-MoS1.85-6%Ohm junction (36.8μmol g-1cath-1) was 1.9 and 6.9-fold higher than that of BiOBr/1T-MoS1.85-6%and 1T-MoS1.85,*** work provides a new insight into the design of Ohm junction with reinforced IEF for efficient interfacial charge carrier transfer and oriented accumulation towards efficient N2fixation.

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Engagement of N^(6)-methyladenisine methylation of Gng4 mRNA in astrocyte dysfunction regulated by CircHECW2

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1644-1660页

作者： Ying Bai Di Chang Hui ren Minzi Ju Yu Wang Biling Chen Han Li Xue Liu Daxing Li Xinchen Huo Xiaofei Guo Mengze tong Ying Tan Honghong Yao Bing Han Department of Pharmacology Jiangsu Provincial Key Laboratory of Critical Care MedicineSchool of MedicineSoutheast UniversityNanjing 210009China Department of Radiology Zhongda HospitalJiangsu Key Laboratory of Molecular and Functional ImagingMedical School of Southeast UniversityNanjing 210009China Co-Innovation Center of Neuroregeneration Nantong UniversityNantong 226001China Institute of Life Sciences Key Laboratory of Developmental Genes and Human DiseaseSoutheast UniversityNanjing 210096China Center for Global Health School of Public HealthNanjing Medical UniversityNanjing 211166China

The N^(6)-methyladenosine(m^(6)A)modification is the most prevalent modification of eukaryotic mRNAs and plays a crucial role in various physiological processes by regulating the stability or function of target *** evidence has suggested that m6A methylation may be involved in the pathological process of major depressive disorder(MDD),a common neuropsychiatric disorder with an unclear ***,we found that the levels of the circular RNA HECW2(circHECW2)were significantly increased in the plasma of both MDD patients and the chronic unpredictable stress(CUS)mouse ***,the downregulation of circHECW2 attenuated astrocyte dysfunction and depression-like behaviors induced by ***,we demonstrated that the downregulation of circHECW2 increased the expression of the methylase WTAP,leading to an increase in Gng4 expression via m^(6)A *** findings provide functional insight into the correlation between circHECW2 and m^(6)A methylation,suggesting that circHECW2 may represent a potential target for MDD treatment.

关键词： N^(6)-Methyladenosine Depression circHECW2 Astrocyte WTAP Ubiquitination GNG4 Dysfunction

Coulomb-assisted nonlocal electron transport between two pairs of Majorana bound states in a superconducting island

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Chinese Physics B 2024年第5期33卷 275-279页

作者：王浩迪任俊潼吕海峰柯莎莎 School of Physics University of Electronic Science and Technology of ChinaChengdu 610054China

We investigate the nonlocal transport modulated by Coulomb interactions in devices comprising two interacting Majorana wires,where both nanowires are in proximity to a mesoscopic superconducting(SC)*** Majorana bound state(MBS)is coupled to one lead via a quantum dot with resonant *** this device,the nonlocal correlations can be induced in the absence of Majorana energy *** find that the negative differential conductance and giant current noise cross correlation could be induced,due to the interplay between nonlocality of MBSs and dynamical Coulomb blockade *** feature may provide a signature for the existence of the MBSs.

关键词： Majorana bound states superconducting island current cross correlation

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A blockchain-based data auditing scheme with key-exposure resistance for IIoT

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Science China(Information Sciences) 2024年第2期67卷 327-328页

作者： Pan YANG Jingli ren Henan Academy of Big Data Zhengzhou University

The Industrial Internet of Things(IIoT) enables enterprises to collect data from end devices and outsource the data to cloud servers for flexible data sharing. Public auditing plays an important role in ensuring the integrity of the *** are blockchain-based public auditing schemes that utilize smart contracts to achieve decentralized verification(such as [1]),

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