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Adhesion Performances Between Two Orthotropic Solids Influenced by Temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： Qing-Hui luo Yue-Ting Zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models bel.ng to isothermal adhesion theories,where the effect of temperature on adhesion was ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,which are solved analytically with the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors between orthotropic solids is *** is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model Temperature Griffith energy balance

Practical Prescribed Time Tracking Control With Bounded Time-Varying Gain Under Non-Vanishing Uncertainties

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 219-230页

作者： Dahui luo Yujuan Wang Yongduan Song the Key laboratory of Dependable Service Computing in Cyber Physical Society Ministry of EducationChongqing UniversityChongqing 400044 the School of Automation Chongqing UniversityChongqing 400044 the Star Institute for Intelligent Systems Chongqing 400044 IEEE

This paper investigates the prescribed-time control(PTC) problem for a class of strict-feedback systems subject to non-vanishing uncertainties. The coexistence of mismatched uncertainties and non-vanishing disturbances makes PTC synthesis nontrivial. In this work, a control method that does not involve infinite time-varying gain is proposed, leading to a practical and global prescribed time tracking control solution for the strict-feedback systems, in spite of both the mismatched and nonvanishing uncertainties. Different from methods based on control switching to avoid the issue of infinite control gain that involves control discontinuity at the switching point, in our method a softening unit is exclusively included to ensure the continuity of the control action. Furthermore, in contrast to most existing prescribed-time control works where the control scheme is only valid on a finite time interval, in this work, the proposed control scheme is valid on the entire time interval. In addition, the prior information on the upper or lower bound of gi is not in need,enlarging the applicability of the proposed method. Both the theoretical analysis and numerical simulation confirm the effectiveness of the proposed control algorithm.

关键词： Adaptive control prescribed time control(PTC) strict-feedback systems tracking control

A risk assessment method considering risk attributes and work safety informational needs and its application

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Chinese Journal of Chemical Engineering 2024年第4期68卷 253-262页

作者： Cong luo Yunsheng Zhao Ke Xu School of Political Science and Public Administration Shandong UniversityQingdao 266200China Faculty of Engineering China University of GeosciencesWuhan 430074China Department of Emergency Management of Hubei Province Wuhan 430064China

The technological revolution has spawned a new generation of industrial systems,but it has also put forward higher requirements for safety management accuracy,timeliness,and *** assessment needs to evolve to address the existing and future chall.nges by considering the new demands and advancements in safety *** study aims to propose a systematic and comprehensive risk assessment method to meet the needs of process system safety *** methodology first incorporates possibility,severity,and dynamicity(PSD)to structure the“51X”evaluation indicator system,including the inherent,management,and disturbance risk ***,the four-tier(risk point-unit-enterprise-region)risk assessment(RA)mathematical model has been established to consider supervision *** in conclusion,the application of the PSD-RA method in ammonia refrigeration workshop cases and safety risk monitoring systems is presented to illustrate the feasibility and effectiveness of the proposed PSD-RA method in safety *** findings show that the PSD-RA method can be well integrated with the needs of safety work informatization,which is also helpful for implementing the enterprise's safety work responsibility and the government's safety supervision responsibility.

关键词： Risk assessment Safey “51X”evaluation indicator system Four-tier risk assessment model Risk attributes Process system

Sequential Inverse Optimal Control of Discrete-Time Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 608-621页

作者： Sheng Cao Zhiwei luo Changqin Quan the Graduate School of System Informatics Kobe University Kobe 657-8501Japan

This paper presents a novel sequential inverse optimal control(SIOC)method for discrete-time systems,which calculates the unknown weight vectors of the cost function in real time using the input and output of an optimally controlled discrete-time *** proposed method overcomes the limitations of previous approaches by eliminating the need for the invertible Jacobian *** calculates the possible-solution spaces and their intersections sequentially until the dimension of the intersection space decreases to *** remaining one-dimensional vector of the possible-solution space’s intersection represents the SIOC *** paper presents clear conditions for convergence and addresses the issue of noisy data by clarifying the conditions for the singular values of the matrices that relate to the possible-solution *** effectiveness of the proposed method is demonstrated through simulation results.

关键词： Inverse optimal control promised calculation step sequential calculation

Optimal impulsive rendezvous for highly elliptical orbits using linear primer vector theory

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Chinese Journal of Aeronautics 2024年第3期37卷 194-207页

作者： Maozhang ZHEng Jianjun luo Zhaohui DAng National Key laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an 710072China

In this paper,minimum-fuel rendezvous is investigated for the case in which the reference orbit is highly *** this end,the well-known Tschauner-Hempel equations are used to describe the relative motions between rendezvous spacecraft and the ***’s primer vector theory is then applied on this linear but time-varying *** analytical solution of the required primer vector for this problem is then derived by using a recently developed *** the existing non-optimal solutions which don’t satisfy the conditions,the methods are further designed to improve the performance by shifting impulses or adding a new ***,two algorithms are developed for free-impulse time-fixed rendezvous *** first algorithm can determine the globally optimal trajectory with the optimal number of *** second one enables for fast trajectory *** proposed algorithms have been successfully applied to coplanar and three-dimensional rendezvous problems in which the target is flying on highly elliptical orbits.

关键词： Orbital transfer Optimal trajectory Primer vector Tschauner-Hempel equations Globally planning Fast planning

Binary Hybrid Artificial Hummingbird with Flower Pollination Algorithm for Feature Selection in Parkinson’s Disease Diagnosis

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Journal of Bionic Engineering 2024年第2期21卷 1003-1021页

作者： liuyan Feng Yongquan Zhou Qifang luo College of Artificial Intelligence Guangxi University for NationalitiesNanning530006China Xiangsihu College of Guangxi University for Nationalities Nanning532100GuangxiChina Guangxi Key laboratories of Hybrid Computation and IC Design Analysis Nanning530006China

Parkinson’s disease is a neurodegenerative disorder that inflicts irreversible damage on *** experimental data regarding Parkinson’s patients are redundant and irrelevant,posing significant chall.nges for disease ***,there is a need to devise an effective method for the selective extraction of disease-specific information,ensuring both accuracy and the utilization of fewer *** this paper,a Binary Hybrid Artificial Hummingbird and Flower Pollination Algorithm(FPA),called BFAHA,is proposed to solve the problem of Parkinson’s disease diagnosis based on speech ***,combining FPA with Artificial Hummingbird Algorithm(AHA)can take advantage of the strong global exploration ability possessed by FPA to improve the disadvantages of AHA,such as premature convergence and easy fall.ng into local ***,the Hemming distance is used to determine the difference between the other individuals in the population and the optimal individual after each iteration,if the difference is too significant,the cross-mutation strategy in the genetic algorithm(GA)is used to induce the population individuals to keep approaching the optimal individual in the random search process to speed up finding the optimal ***,an S-shaped function converts the improved algorithm into a binary version to suit the characteristics of the feature selection(FS)*** this paper,10 high-dimensional datasets from UCI and the ASU are used to test the performance of BFAHA and apply it to Parkinson’s disease *** with other state-of-the-art algorithms,BFAHA shows excellent competitiveness in both the test datasets and the classification problem,indicating that the algorithm proposed in this study has apparent advantages in the field of feature selection.

关键词： Artificial Hummingbird Algorithm Flower pollination algorithm Feature selection Parkinson’s disease Meta-heuristic

Combination of diketone and PAO to achieve macroscale oil-based superlubricity at relative high contact pressures

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Friction 2024年第5期12卷 869-883页

作者： Shaonan DU Chenhui ZHAng Zhi luo State Key laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing100084China Beijing National laboratory of Molecular Sciences CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing100190China

1-(4-ethylphenyl)-nonane-1,3-dione(0206)is an oil-soluble liquid molecule with rod-like *** this study,the chelate(0206-Fe)with octahedral structure was prepared by the reaction of ferric chloride and 1,*** experimental results show that when using 0206 and a mixed solution containing 60%0206-Fe and 40%0206(0206-Fe(60%))as lubricants of the steel friction pairs,superlubricity can be achieved(0.007,0.006).But their wear scar diameters(WSD)were very large(532µm,370µm),which resulted in the pressure of only 44.3 and 61.8 MPa in the contact areas of the friction *** 0206-Fe(60%)was mixed with PAO6,it was found that the friction coefficient(COF)decreased with increase of 0206-Fe(60%)in the *** the ratio of 0206-Fe(60%)to PAO6 was 8:2(PAO6(20%)),it exhibited better comprehensive tribological properties(232.3 MPa).Subsequent studies have shown that reducing the viscosity of the base oil in the mixed solution helped to reduce COF and increased *** the COF,contact pressure,and running-in time,it was found that the mixed lubricant(Oil3(20%))prepared by the base oil with a viscosity of 19.7 mPa·s(Oil3)and 0206-Fe(60%)exhibited the best tribological properties(0.007,161.4 MPa,3,100 s).

关键词： diketone oil-based lubricants chelate superlubricity

Biological Interaction and Imaging of Ultrasmall Gold Nanoparticles

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Nano-Micro letters 2024年第3期16卷 69-98页

作者： Dongmiao Sang Xiaoxi luo Jinbin liu Key laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China

Ultrasmall gold nanoparticles(AuNPs)typically includes atomically precise gold nanoclusters(AuNCs)and AuNPs with a core size below 3 *** as a bridge between small molecules and traditional inorganic nanoparticles,the ultrasmall AuNPs show the unique advantages of both small molecules(e.g.,rapid distribution,renal clearance,low non-specific organ accumulation)and nanoparticles(e.g.,l.ng blood circulation and enhanced permeability and retention effect).The emergence of ultrasmall AuNPs creates significant opportunities to address many chall.nges in the health field including disease diagnosis,monitoring and *** the nano–bio interaction dictates the overall biological applications of the ultrasmall AuNPs,this review elucidates the recent advances in the biological interactions and imaging of ultrasmall *** begin with the introduction of the factors that influence the cellular interactions of ultrasmall *** then discuss the organ interactions,especially focus on the interactions of the liver and *** further present the recent advances in the tumor interactions of ultrasmall *** addition,the imaging performance of the ultrasmall AuNPs is summarized and ***,we summarize this review and provide some perspective on the future research direction of the ultrasmall AuNPs,aiming to accelerate their clinical translation.

关键词： Ultrasmall gold nanoparticle Cellular interaction Organ interaction Tumor interaction Bioimaging

Optimization of biofuel supply chain integrated with petroleum refineries under carbon trade policy

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 113-122页

作者： Wenhui Zhang Yiqing luo Xigang Yuan Chemical Engineering Research Center School of Chemical Engineering and TechnologyTianjin UniversityTianjin300350China State Key laboratory of Chemical Engineering Tianjin UniversityTianjin300350China

The use of fossil fuels results in significant carbon dioxide *** have been increasingly adopted as sustainable alternatives to fossil fuel to address this environmental *** petroleum refineries into biofuel supply chains is an effective approach to mitigating greenhouse gas emissions and improving environmental *** this study,an integrated supply chain optimization framework was established,considering the carbon trade *** addition,a mixed-integer nonlinear programming model was developed to optimize the selection of biomass suppliers,construction of pretreatment plants and biorefineries,integration of petroleum refineries,and selection of transportation routes with the objective of minimizing the total annual *** example is presented to illustrate the applicability of the *** optimization results show that integrating petroleum refineries into biofuel supply chains effectively mitigates carbon *** trade policies can have a direct impact on the total annual cost and carbon emissions of the supply chain.

关键词： renewable energy biofuel supply chain carbon trade policy