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science China(Information sciences) 2024年第6期67卷 328-341页

作者： Xian-Ming ZHANG Qing-Long HAN Bao-Lin ZHANG Xiaohua GE Dawei ZHANG School of science Computingand Engineering TechnologiesSwinburne University of Technology college of Automation and electronic engineering Qingdao University of Science & Technology School of Mathematics Shandong University

This paper is concerned with event-triggered H∞control of sampled-data systems. Its novelties lie in three aspects:（i） A novel accumulated-state-error-based event-triggered scheme is introduced by comparing the integral of the state error from tk to t with the system state sampled at tk. This condition works well due to the fact that the so-called Zeno behaviour does not occur.（ii） A novel Lyapunov functional is constructed to establish a criterion to ensure some certain H∞performance of the closed-loop system. This Lyapunov functional is dependent on the integral of the state error involved in the event-triggered scheme.（iii） Under the event-triggered sampling scheme, suitable state-feedback controllers can be designed rather than be given a priori. Moreover, a self-triggered implementation of the proposed event-triggered sampling scheme is presented as well. Finally, a batch reactor model and an inverted pendulum system are given to demonstrate the effectiveness of the proposed method.

关键词： event-triggered sampling self-triggered implementation H ∞ control looped-functional

A Novel Trajectory Tracking Control of AGV Based on Udwadia-Kalaba Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1069-1071页

作者： Rongrong Yu Han Zhao Shengchao Zhen Kang Huang Xianmin Chen Hao Sun Ke Shao the School of mechanical engineering Hefei University of TechnologyHefei 230009China the college of mechanical and electronic engineering Shandong University of Science and TechnologyQingdao 266590China the university of science and technology of China Hefei 230026China

Dear Editor,This letter is about an automated guided vehicle(AGV)trajectory tracking control method based on Udwadia-Kalaba(U-K)*** method provides a novel,concise and explicit motion equation for constrained mechanical systems with holonomic and/or nonholonomic constraints as well as constraints that may be ideal or *** this letter.

关键词： letter constraints constrained

Large-scale particle trapping by acoustic vortices with a continuously variable topological charge

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Chinese Physics B 2024年第7期33卷 398-406页

作者：庄昊霏张清源胡格昊王青东杜立彬 college of Ocean science and engineering Shandong University of Science and TechnologyQingdao 266590China Department of Radiology the Affiliated Hospital of Qingdao UniversityQingdao 266000China college of electronic and Information engineering Shandong University of Science and TechnologyQingdao 266590China

Strengthened directivity with higher-order side lobes can be generated by the transducer with a larger radius at a higher frequency. The multi-annular pressure distributions are displayed in the cross-section of the acoustic vortices(AVs)which are formed by side lobes. In the near field, particles can be trapped in the valley region between the two annuli of the pressure peak, and cannot be moved to the vortex center. In this paper, a trapping method based on a sector transducer array is proposed, which is characterized by the continuously variable topological charge(CVTC). This acoustic field can not only enlarge the range of particle trapping but also improve the aggregation degree of the trapped particles. In the experiments, polyethylene particles with a diameter of 0.2 mm are trapped into the multi-annular valleys by the AV with a fixed topological charge. Nevertheless, by applying the CVTC, particles outside the radius of the AV can cross the pressure peak successfully and move to the vortex center. Theoretical studies are also verified by the experimental particles trapping using the AV with the continuous variation of three topological charges, and suggest the potential application of large-scale particle trapping in biomedical engineering.

关键词： acoustic vortices sector transducer array trapping particle continuously variable topological charge

Solution-processed rare-earth thulium oxide with high permittivity for low-voltage transistor and inverters applications

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Journal of Rare Earths 2024年第8期42卷 1604-1609,I0007页

作者： Daiming Liu Fei Wang Yongtao Zhang Ya'nan Ding shandong engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science&TechnologyQingdao266061China college of electronic and Information engineering Shandong University of Science and TechnologyQingdao266590China

The use of high-permittivity(high-k) thin films as gate dielectrics is essential in the development of lowpower electronics,In this work,rare-earth thulium oxide(Tm_(2)O_(3)) thin films were prepared by a facile solution process and annealed at various temperatures from 400 to 700℃.The evolution of the physical and dielectric properties of Tm_(2)O_(3) thin film with annealing temperature was *** is demonstrated that the Tm_(2)O_(3) thin film annealed at 600℃ exhibits the optimal performance,including a low leakage current of 3×10^(-10) A/cm^(2),a large areal capacitance of 250 nF/cm^(2) at 100 Hz,and a high permittivity value of *** Tm_(2)O_(3) thin film as a gate insulator was integrated into the thin film transistor(TFT) employing In_(2)O_(3)-based semiconducting *** In_(2)O_(3) TFT with 600℃-annealed Tm_(2)O_(3) dielectric exhibits the superior perfo rmance,with a high I_(on)/I_(off) of 1.65×10^(7),a small subthre shold swing(SS) value of 0.2 V/dec,a V_(TH) of+1.8 V,and a mobility of 1.68 cm^(2)/(V·s).Furthermore,an inverter constructed by connecting the TFT with a resistor exhibits full-swing *** work provides a facile and appealing method for preparing the high-k Tm_(2)O_(3) thin films as alternative gate dielectrics with the potential for use in low-power electronics and logic circuit applications.

关键词： Rare earths Tm_(2)O_(3) Dielectric Transistor Inverter

Cross-layer all-interface defect passivation with pre-buried additive toward efficient all-inorganic perovskite solar cells

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Carbon Energy 2024年第9期6卷 283-291页

作者： Qiurui Wang Jingwei Zhu Yuanyuan Zhao Yijie Chang Nini Hao Zhe Xin Qiang Zhang Cong Chen Hao Huang Qunwei Tang college of mechanical and electronic engineering Shandong University of Science and TechnologyQingdaoChina college of Materials science and engineering Sichuan UniversityChengduChina Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials School of ResourcesEnvironment and MaterialsGuangxi UniversityNanningChina Institute of Carbon Neutrality College of Chemical and Biological EngineeringShandong University of Science and TechnologyQingdaoChina

The buried interface in the perovskite solar cell(PSC)has been regarded as a breakthrough to boost the power conversion efficiency and ***,a comprehensive manipulation of the buried interface in terms of the transport layer,buried interlayer,and perovskite layer has been largely ***,we propose the use of a volatile heterocyclic compound called 2-thiopheneacetic acid(TPA)as a pre-buried additive in the buried interface to achieve cross-layer all-interface defect passivation through an in situ bottom-up infiltration diffusion *** not only suppresses the serious interfacial nonradiative recombination losses by precisely healing the interfacial and underlying defects but also effectively enhances the quality of perovskite film and releases the residual strain of perovskite *** to this versatility,TPA-tailored CsPbBr3 PSCs deliver a record efficiency of 11.23% with enhanced long-term *** breakthrough in manipulating the buried interface using TPA opens new avenues for further improving the performance and reliability of PSC.

关键词： buried interfaces charge recombination defect passivation inorganic perovskite solar cells strain relaxation

Reinforced SnO_(2) tensile-strength and“buffer-spring”interfaces for efficient inorganic perovskite solar cells

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Carbon Energy 2024年第6期6卷 282-291页

作者： Yuanyuan Zhao Lei Gao Qiurui Wang Qiang Zhang Xiya Yang Jingwei Zhu Hao Huang Jialong Duan Qunwei Tang college of mechanical and electronic engineering Shandong University of Science and TechnologyQingdaoChina Institute of New Energy technology College of Information Science and TechnologyJinan UniversityGuangzhouChina college of Materials science and engineering Sichuan UniversityChengduChina Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials School of ResourcesEnvironment and MaterialsGuangxi UniversityNanningChina Institute of Carbon Neutrality College of Chemical and Biological EngineeringShandong University of Science and TechnologyQingdaoChina

Suppressing nonradiative recombination and releasing residual strain areprerequisites to improving the efficiency and stability of perovskite solar cells(PSCs).Here,long-chain polyacrylic acid(PAA)is used to reinforce SnO_(2)film and passivate SnO_(2)defects,forming a structure similar to“reinforcedconcrete”with high tensile strength and fewer ***,PAA is also introduced to the SnO_(2)/perovskite interface as a“buffer spring”torelease residual strain,which also acts as a“dual-side passivation interlayer”to passivate the oxygen vacancies of SnO_(2)and Pb dangling bonds in *** a result,the best inorganic CsPbBr_(3)PSC achieves a championpower conversion efficiency of 10.83%with an ultrahigh open-circuit voltageof 1.674 *** unencapsulated PSC shows excellent stability under 80%relative humidity and 80℃over 120 days.

关键词： charge recombination defect passivation inorganic perovskite solar cells interfacial modification strain relaxation

Design and test of the plant-correcting reel for harvesting lodging garlic plants

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International Journal of Agricultural and Biological engineering 2024年第1期17卷 59-68页

作者： Yuhua Li Chao Li Lupeng Liu Kai Zhou Jialin Hou college of mechanical and electronic engineering Shandong Agricultural UniversityTai’an 271018ShandongChina college of Biosystems engineering&Food science Zhejiang UniversityHangzhou 310058China

Crops are prone to lodging with the decline of stem moisture and the intervention of other factors in the mature harvest period,such as garlic,which is difficult to harvest *** solve this problem,the plant-correcting reel for harvesting lodging garlic plants,bumped and deformed with plants many times to pull and lift them into a conveyor,is proposed in this *** analyzed the motion trajectory equation and key influencing factors of the reel and defined the lifting and plant-correcting stages as three processes of contact,stirring and *** example,the contact deformation model and system energy equations were established in the contact ***,in the stirring process,the garlic plant-correcting conditions were established through the dynamic simulation test analysis of garlic seedling trajectories and the deflection model of garlic stem was ***,in the release process,the expressions of rubber bars rotation and garlic plant offset bending curvature were constructed and the optimal number and distribution form of bars were ***,the mechanism and key operating parameters of the auxiliary lifting mechanism of the divider were *** the single-factor test,the influence of reel speed,forward speed and reel height on the success feeding rate was analyzed under different bars distribution forms;Through multi-factor experiments,the interaction contour map of various factors was *** reel speed,forward speed and reel height were 3 rad/s,3.5 m/s,and 540 mm,the feeding success rate was 98.73%.The optimization factors were tested and verified,which met the operational requirements of a high feeding success rate and low loss rate of garlic *** study combines laboratory virtual as well as field experiments and analyzes of trajectory of bars,contact deformation and deflection model of garlic plant,and reel rotation and garlic plant offset bending curvature to solve the problem of ga

关键词： feeding success rate lodging garlic harvesting reel plant model field test

Macro-micro behaviors and failure mechanism of frozen weakly cemented mudstone

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Journal of Rock Mechanics and Geotechnical engineering 2024年第4期16卷 1337-1347页

作者： Xianzhou Lyu Jijie Du Hao Fu Dawei Lyu Weiming Wang college of Earth science and engineering Shandong University of Science and TechnologyQingdao266590China college of Civil engineering and Architecture Shandong University of Science and TechnologyQingdao266590China

Understanding the mechanical properties and multiscale failure mechanism of frozen soft rock is an important prerequisite for the construction safety of tunnels,artificially frozen ground and other infrastructure in cold *** this study,the triaxial compression test are performed on mudstone in the weakly cemented soft rock strata in the mining area of western China,and the mechanical characteristics and failure mechanism of weakly cemented mudstone are systematically investigated under the combined action of freezing and ***,the quantitative relationship between the microstructural parameters and the macroscopic strength and deformation parameters is established based on fractal ***,the failure mechanism of frozen weakly cemented mudstone is revealed on both micro- and *** results show that temperature and confining pressure significantly affects the elastic modulus and peak strength of weakly cemented *** decreasing temperature,the compressive strength increases,while the corresponding peak strain decreases *** the deformation curve,the plastic deformation stage is shortened,and the brittle fracture feature at the post-peak stage is more prominent,and the elastic modulus correspondingly increases with decreasing *** low-temperature conditions,most of the weakly cemented mudstone undergoes microscopic shear failure along the main fracture *** micro-fracture morphology characteristics of weakly cemented mudstone under different temperatures are quantified via the fractal dimension,and an approximately exponential relationship can be obtained among the fractal dimension and the temperature,compressive strength and elastic modulus.

关键词： Weakly cemented mudstone Artificial freezing mechanical properties Linkage destruction mechanism Fractal dimension

Defects and morphology engineering for constructing V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S nanotube heterojunction arrays toward efficient bifunctional electrocatalyst for overall water splitting

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Journal of Energy Chemistry 2024年第7期94卷 29-40页

作者： Wenyuan Sun Alan Meng Lei Wang Guicun Li Jinfeng Cui Yongkai Sun Zhenjiang Li college of Materials science and engineering Qingdao University of Science and TechnologyQingdao 266042ShandongChina Key Laboratory of Optic-electric Sensing and Analytical Chemistryfor Life science MOE College of Chemistry and Molecular EngineeringQingdao Universityof Science and TechnologyQingdao 266042ShandongChina college of Environment and Safety engineering Qingdao University of Science and TechnologyQingdao 266042ShandongChina Qingdao Huanghai university Qingdao 266000ShandongChina college of Electromechanical engineering Qingdao University of Science and TechnologyQingdao 266061ShandongChina

The development of highly active,stable and inexpensive electrocatalysts for hydrogen production by defects and morphology engineering remains a great ***,S vacancies-rich Ni_(3)S_(2)@Cu_(2)S nan-otube heterojunction arrays were in-situ grown on copper foam(V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF)for efficient electrocatalytic overall water *** the merits of nanotube arrays and efficient electronic mod-ulation drived by the OD vacancy defect and 2D heterojunction defect,the resultant V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF electrocatalyst exhibits excellent electrocatalytic activity with a low overpotential of 47 mV for the hydrogen evolution reaction(HER)at 10 mA cm^(-2) current density,and 263 mV for the oxygen evolution reaction(OER)at 50 mA cm^(-2) current density,as well as a cell voltage of 1.48 V at 10 mA cm^(-2).Moreover,the nanotube heterojunction arrays endows V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF with outstanding stability in long-term catalytic processes,as confirmed by the continuous chronopotentiom-etry tests at current densities of 10 mA cm^(-2) for 100 h.

关键词： Nanotubearrays Heterojunction Vacancy Bifunctional electrocatalyst Overall water splitting

Effect of Y_(2)O_(3) on microstructure and properties of CoCrFeNiTiNb high entropy alloy coating on Ti-6Al-4V surface by laser cladding

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Journal of Rare Earths 2024年第3期42卷 586-599,I0006页

作者： Zhen Li Wei Zhao Kedong Yu Ning Guo Guangchun Xiao Zhiming Wang Hui Zhang college of mechanical engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China shandong Institute of mechanical Design and Research Jinan250031China

The effects of Y_(2)O_(3) on the microstructure, microhardness, wear resistance, high-temperature oxidation resistance, hot corrosion resistance, and electrochemical corrosion behaviour of CoCrFeNiTiNb high entropy alloy coatings formed on Ti-6Al-4V alloy surfaces were studied. The results show that the addition of Y_(2)O_(3) changes the proportion of the phase but does not change its type. The average grain size is only 1/4.7 of that of the high entropy alloy(HEA) coating, and the fine-grained strengthening leads to increases in the microhardness and wear resistance of 21.8% and 26.9%, respectively. The addition of Y_(2)O_(3) enhances the denseness and bonding properties of the oxide and corrosion product layers, reducing the oxidation and hot corrosion rates by 60.3% and 40.3%, respectively. The addition of Y_(2)O_(3) doubles the corrosion resistance which is attributed to the refinement of the grains, the increased proportion of HCP and TiN, and the weakening of galvanic coupling corrosion.

关键词： Laser cladding High entropy alloy coatings Rare earths Wear properties High temperature properties Electrochemical corrosion