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Design of Model Reference Adaptive Sliding Mode Tracking Controllers for Mismatched Uncertain Dynamic Systems

第37届中国控制会议

作者： chih-chiang cheng cheng-Yun Chu Electrical Engineering Sun Yat-Sen University

Based on the Lyapunov stability theorem, a design methodology of adaptive variable structure tracking controller is proposed in this paper for a class of perturbed nonlinear systems with nonholonomic constraints to solve the trajectory tracking control problems. In the first stage, the nonhomogeneous dynamics constraints of the plant are transformed into a general multichained form, and a desired velocity input function is designed by utilizing backstepping control technique. In the second stage,the proposed controller is designed by using variable structure control（VSC） methodology with adaptive mechanism embedded,so that the tracking errors of both transformed states and the original states are able to achieve asymptotic stability. In addition,the velocity trajectories of the controlled systems can track the desired velocity input function designed in the first stage in a finite time. The upper bounds of perturbations are not required to be known in advance due to employed adaptive ***, a practical example is given for demonstrating the feasibility of the proposed control scheme.

关键词： Variable structure control backstepping control Nonholonomic constraint

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Design of Model Reference Adaptive Sliding Mode Tracking Con...

Control of Corner Separation for a Linear Compressor Cascade via Bionic Slanting Riblets at the Endwall

2009中国控制与决策会议

作者： chih-chiang cheng Hung-An Chen Jia-Ming Hsiao Department of Electrical Engineering National Sun Yat-Sen UniversityKaohsiungTaiwan804 Departmem of Managemem Information System Far East UniversityHsin-ShihTainan County 744Taiwan

＜正＞Based on the Lyapunov stability theorem,a model reference adaptive sliding mode control scheme is proposed in this paper for a class of multi-input multi-output（MIMO） dynamic systems with mismatched model uncertainties and external disturbances in order to solve robust tracking *** this method adaptive mechanisms are employed both in sliding surface function and control effort so that once the dynamics of controlled system enter the designated sliding surface,the trajectories of tracking errors can achieve asymptotic stability even if the mismatched perturbations exist. In addition,with adaptive mechanisms embedded in the proposed control scheme,the controller is able to adapt the unknown upper bound of perturbations without requiring the information of upper bound of perturbations.A numerical example is given for demonstrating the feasibility of the proposed control scheme.

关键词： Sliding Mode Control Adaptive Control Mismatched Perturbations Lyapunov stability theorem

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Journal of Thermal Science 2025年第1期34卷 129-144页

作者： ZHANG Peng LI Yonghong cheng Rixin Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation University of China College of Aeronautical Engineering Civil Aviation University of China

A new passive control approach,utilizing bionic slanting riblets,is employed to mitigate the flow close to the blade endwall in a linear cascade,and its effectiveness and mechanism in controlling corner separation are investigated through numerical *** slanting riblets are positioned at the endwall upstream of the cascade channel,and the influence of riblet height,yaw angle and relative position on the control of corner separation is *** findings indicate that the application of slanting riblets can efficiently counteract corner separation across the stable operational ***,the introduction of riblets with a height of merely 0.1 times the boundary layer thickness results in a significant reduction in total pressure loss by up to 14.53%,while simultaneously enhancing the static pressure coefficient by 21.74%.Flow analysis reveals that minute vortices produced within the riblet channels tend to coalesce,forming a potent large-scale vortex near the boundary layer's base *** phenomenon results in reduced additional losses compared to conventional vortex ***,the induced vortex promotes enhanced mixing between the mainstream flow and boundary layer,inhibiting the lateral displacement of low-energy fluids within the endwall boundary ***,this delays the onset of separation vortex formation and eliminates vortex rings in the corner region,ultimately enhancing the aerodynamic efficiency of the cascade.

关键词： additional losses compressor cascade corner separation slanting riblets vortex generator

Three-dimensional fracture of UO2 ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 169-180页

作者： Wei Xiong Xuan Ye Hongzhang cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Fracture is the primary failure type for the UO2ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional （3D） UO2ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture

Unraveling the impacts of intermolecular interaction on morphology evolution for highly efficient organic solar cells and modules

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Science China Chemistry 2025年第1期68卷 264-272页

作者： Xueqing Ma Yingying cheng Yuqiang Liu Xinming Zheng Guangliu Ran Hongxiang Li Xinyue Cui Andong Zhang Wenkai Zhang Pei cheng Wenchao Huang Zhishan Bo Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry Beijing Normal University College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textiles Qingdao University Key State Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of Technology Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum Studies Beijing Normal University State Key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University

Understanding the effect of intermolecular interaction on the growth dynamic of active layers is critical for advancing organic solar cells(OSCs). However, the diverse structure of donors and acceptors makes the research challenging. Additives with customizable structures and properties could simplify this complexity. Herein, we meticulously tailor two additives of 3,4-ethylenedioxythiophene(EDOT) and 2,5-dibromo-3,4-ethylenedioxythiophene(DBEDOT), possessing distinct intermolecular interaction features to elaborate the inherent relationship. It is found that varied interaction strengths can alter film formation processes. The enhanced intermolecular interaction between the DBEDOT and non-fullerene acceptor BTP-e C9-4F results in pre-aggregation and longer crystallization duration of BTP-e C9-4F, facilitating the formation of films with compact molecular packing and decent phase separation. Thus, exciton dissociation and charge transport become more efficient. Finally, devices processed with DBEDOT exhibit a remarkable power conversion efficiency of 19.35% in small-area OSCs and 14.11% in bladecoated 5 cm × 5 cm organic solar mini-modules. Especially, OSCs can maintain 80% of their initial efficiency after continuous annealing at 85 °C for over 2,100 h.

关键词： organic solar cell non-fullerene acceptor film growth molecular packing intermolecular interaction

Tailoring Light–Matter Interactions in Overcoupled Resonator for Biomolecule Recognition and Detection

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Nano-Micro Letters 2025年第1期17卷 262-280页

作者： Dongxiao Li Hong Zhou Zhihao Ren cheng Xu chengkuo Lee Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Center for Intelligent Sensors and MEMS(CISM) National University of SingaporeSingapore 117608Singapore

Plasmonic nanoantennas provide unique opportunities for precise control of light–matter coupling in surface-enhanced infrared absorption(SEIRA)spectroscopy,but most of the resonant systems realized so far suffer from the obstacles of low sensitivity,narrow bandwidth,and asymmetric Fano resonance ***,we demonstrated an overcoupled resonator with a high plasmon-molecule coupling coefficient(μ)(OC-Hμresonator)by precisely controlling the radiation loss channel,the resonator-oscillator coupling channel,and the frequency detuning *** observed a strong dependence of the sensing performance on the coupling state,and demonstrated that OC-Hμresonator has excellent sensing properties of ultra-sensitive(7.25%nm^(−1)),ultra-broadband(3–10μm),and immune asymmetric Fano *** characteristics represent a breakthrough in SEIRA technology and lay the foundation for specific recognition of biomolecules,trace detection,and protein secondary structure analysis using a single array(array size is 100×100μm^(2)).In addition,with the assistance of machine learning,mixture classification,concentration prediction and spectral reconstruction were achieved with the highest accuracy of 100%.Finally,we demonstrated the potential of OC-Hμresonator for SARS-CoV-2 *** findings will promote the wider application of SEIRA technology,while providing new ideas for other enhanced spectroscopy technologies,quantum photonics and studying light–matter interactions.

关键词： Plasmonic nanoantennas Light-matter interaction Surface-enhanced infrared absorption Overcoupled Biosensing

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A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy

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Computers, Materials & Continua 2025年第1期82卷 997-1026页

作者： Li Ma Cai Dai Xingsi Xue cheng Peng School of Computer Science Shaanxi Normal UniversityXi’an710119China Fujian Provincial Key Laboratory of Big Data Mining and Applications Fujian University of TechnologyFuzhou350118China Information Construction and Management Center and Institute of Artificial Intelligence and Educational New Productivity Ningxia Normal UniversityGuyuan756099China

The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization *** the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search ***,two update strategies based on decomposition are used to update the evolving population and external archive,***,a multiselection strategy is *** first strategy is for the subspace without a non-dominated *** the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global *** second strategy is for the subspace with a non-dominated *** the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local *** third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated *** the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to ***,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search ***,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test *** results show that the proposed algorithm has better performance.

关键词： Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy

lncRNA SNHG4 enhanced gastric cancer progression by modulating miR-409-3p/CREB1 axis

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Oncology Research 2025年第1期33卷 185-198页

作者： ZHOUYANG cheng YUCHEN HUA YANG CAO JUN QIN Department of General Surgery Affiliated Hospital of Nantong UniversityNantong226001China Department of Surgery Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong226001China Department of Operation Affiliated Hospital of Nantong UniversityNantong226001China

Objective:Gastric cancer(GC)is a globally common cancer characterized by high incidence and mortality *** in the molecular understanding of GC provide promising targets for GC diagnosis and *** non-coding RNAs(lncRNAs)and their downstream regulators are regarded to be implicated in the progression of multiple types of *** have shown that the lncRNA small nucleolar RNA host gene 4(SNHG4)serves as a tumor promoter in various malignancies,while its function in GC has yet to be ***,our study aimed to explore the role and underlying mechanism of SNHG4 in ***:We used qRT-PCR to analyze SNHG4 expression in GC tissues and ***-Meier analysis was used to assess the correlation between SNHG4 expression and the survival rate of GC *** function experiments such as CCK-8,BrdU,colony formation,flow cytometry analysis,and transwell were performed to explore the effects of SNHG4 on GC cell proliferation,apoptosis,cell cycle,migration,and *** also established xenograft mouse models to explore the effect of SNHG4 on GC tumor ***,dual luciferase reporter assay was used to verify the interaction between SNHG4 and miR-409-3p and between miR-409-3p and cAMP responsive element binding protein 1(CREB1).Results:The results indicated that SNHG4 was overexpressed in GC tissues and cell lines,and was linked with poor survival rate of GC ***4 promoted GC cell proliferation,migration,and invasion while inhibiting cell apoptosis and cell cycle arrest in *** in vivo experiment indicated that SNHG4 facilitated GC tumor ***,SNHG4 was demonstrated to bind to ***,CREB1 was directly targeted by *** assays demonstrated that miR-409-3p deficiency reversed the suppressive impact of SNHG4 knockdown on GC cell ***,miR-409-3p was also revealed to inhibit GC cell proliferation,migration,and invasion by targeting CREB1

关键词： Gastric cancer Small nucleolar RNA host gene 4(SNHG4) MicroRNA-409-3p(miR-409-3p) cAMP responsive element binding protein 1(CREB1)

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping cheng Jian WEI Chao YUAN Bin YU chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

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