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Optimal Energy Efficiency Based High-speed Flying Control Method for Hydraulic Quadruped Robot

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Journal of Bionic Engineering 2024年第3期21卷 1156-1173页

作者： Qingjun Yang Zhenyang Zhang rui Zhu Dianxin wang School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150000China Nanjing Chenguang Group Co.Ltd Nanjing210006China

Herein,a control method based on the optimal energy efficiency of a hydraulic quadruped robot was proposed,which not only realizes the optimal energy efficiency of flying trot gait but also ensures the stability of high-speed ***,the energy consumption per unit distance was adopted as the energy efficiency evaluation index based on the constant pressure oil supply characteristics of the hydraulic system,and the global optimization algorithm was adopted to solve the optimal ***,the gait parameters that affect the energy efficiency of quadruped were analyzed and the mapping relationship between each parameter and energy efficiency was captured,so as to select the optimum combination of energy efficiency parameters,which is significant to improve endurance ***,to ensure the stability of the high-speed flying trot gait motion of the hydraulic quadruped robot,the active compliance control strategy was ***,the proposed method was successfully verified by simulations and *** experimental results reveal that the flying trot gait of the hydraulic quadruped robot can be stably controlled at a speed of 2.2 m/s.

关键词： Hydraulic quadruped robot Flying trot Energy efficiency Active compliance control

A photogrammetric approach for quantifying the evolution of rock joint void geometry under varying contact states

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International Journal of Mining Science and Technology 2024年第4期34卷 461-477页

作者： rui Yong Changshuo wang Nick Barton Shigui Du Institute of Rock Mechanics Ningbo UniversityNingbo 315211China Nick Barton&Associates Fjordveien 65cHøvik 1363Norway

Accurate measurement of the evolution of rock joint void geometry is essential for comprehending the distribution characteristics of asperities responsible for shear and seepage ***,existing techniques often require specialized equipment and skilled operators,posing practical *** this study,a cost-effective photogrammetric approach is ***,local coordinate systems are established to facilitate the alignment and precise quantification of the relative position between two halves of a rock ***/pull tests are conducted on rock joints with varying roughness levels to induce different contact states.A high-precision laser scanner serves as a benchmark for evaluating the photogrammetry *** certain deviations exist,the measured evolution of void geometry is generally consistent with the qualitative findings of previous *** photogrammetric measurements yield comparable accuracy to laser scanning,with maximum errors of 13.2%for aperture and 14.4%for void *** joint matching coefficient(JMC)measurement errors are below 20%.Larger measurement errors occur primarily in highly mismatched rock joints with JMC values below 0.2,but even in cases where measurement errors exceed 80%,the maximum JMC error is only ***,the proposed photogrammetric approach holds promise for widespread application in void geometry measurements in rock joints.

关键词： Rock joint Void geometry evolution Photogrammetry Aperture Void volume Joint matching coefficient

A kinetic resolution accompanied chirality transformation process for asymmetric synthesis of chiral phenol,oxaziridine,andα-hydroxyl cyclic ketone

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Science China Chemistry 2024年第9期67卷 2989-2997页

作者： Pengxin wang Xiaoyong Zhang Lingqing wang rui wang Dongxu Yang Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical Sciences&Research Unit of Peptide ScienceChinese Academy of Medical SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China School of Sciences Great Bay UniversityDongguan 523000China Institute of Systems and Physical Biology Shenzhen Bay LaboratoryShenzhen 518055China

Chirality transformation is a basic,attractive,and important strategy for obtaining enantioenriched products with desired chiral *** reported chirality conversion reaction often involves the process from one type of chirality to another *** better utilize the chirality transformation strategy for obtaining two or more products with different chiral elements in a single reaction,a new method of kinetic resolution accompanied by a chirality transformation protocol is proposed and successfully realized in this *** process is used for the asymmetric oxidation of phenol compounds along with the kinetic resolution of oxaziridines.A wide scope of products,including axially chiral phenols,oxaziridines,andα-hydroxyl cyclic ketones were smoothly obtained in high levels of yields and enantioselectivities in the developed *** products can be readily used for the synthesis of various types of chiral ligands,which are potential choices for other catalytic asymmetric reactions.

关键词： chirality transformation kinetic resolution accompanied axially chiral phenols chiral oxaziridines

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Quasi-two-dimensional strong liquid-like dynamics of surface atoms in metallic glasses

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 102-109页

作者： Bing wang Xuanqiao Gao rui Su Pengfei Guan School of Physical Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Innovation Center NPU Chongqing Northwestern Polytechnical UniversityChongqing 401135China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Northwest Institute for Nonferrous Metal Research Xi'an 710016China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi University Hangzhou 310018China Beijing Computational Science Research Center Beijing 100093China

The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth.

关键词： metallic glasses thermal stability invariant surface dynamics potential energy landscape dynamic anisotropy and heterogeneity

A study of novel real-time power balance strategy with virtual asynchronous machine control for regional integrated electric-thermal energy systems

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Science China(Technological Sciences) 2024年第7期67卷 2074-2086页

作者： wang rui LI Ming-Jia wang YiBo SUN QiuYe ZHANG PinJia College of Information Science and Engineering Northeastern UniversityShenyang 110819China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

The development of regional integrated electric-thermal energy systems(RIETES) is considered a promising direction for modern energy supply systems. These systems provide a significant potential to enhance the comprehensive utilization and efficient management of energy resources. Therein, the real-time power balance between supply and demand has emerged as one pressing concern for system stability operation. However, current methods focus more on minute-level and hour-level power optimal scheduling methods applied in RIETES. To achieve real-time power balance, this paper proposes one virtual asynchronous machine(VAM) control using heat with large inertia and electricity with fast response speed. First, the coupling timescale model is developed that considers the dynamic response time scales of both electric and thermal energy systems. Second, a real-time power balance strategy based on VAM control can be adopted to the load power variation and enhance the dynamic frequency response. Then, an adaptive inertia control method based on temperature variation is proposed, and the unified expression is further established. In addition, the small-signal stability of the proposed control strategy is validated. Finally, the effectiveness of this control strategy is confirmed through MATLAB/Simulink and HIL(Hardware-in-the-Loop) experiments.

关键词： regional integrated electric-thermal energy systems real-time power balance virtual asynchronous machine adaptive inertia small-signal stability

Double Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 75-90页

作者： Meng Chen wang-xue Chen rui Yang Department of Mathematics and Statistics Jishou UniversityJishou416000China

The traditional simple random sampling(SRS)design method is inefficient in many *** proposed some new designs to increase *** this paper,as a variation of moving extremes ranked set sampling(MERSS),double MERSS(DMERSS)is proposed and its properties for estimating the population mean are *** turns out that,when the underlying distribution is symmetric,DMERSS gives unbiased estimators of the population ***,it is found that DMERSS is more efficient than the SRS and MERSS methods for usual symmetric distributions(normal and uniform).For asymmetric distributions considered in this study,the DMERSS has a small bias and it is more efficient than SRS for usual asymmetric distribution(exponential)for small sample sizes.

关键词： double moving extremes ranked set sampling symmetric distribution efficiency

Fully distributed dynamic event-triggered formation-containment tracking for multiagent systems with multiple types of disturbances

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Science China(Information Sciences) 2024年第1期67卷 168-186页

作者： Weihua LI Huaguang ZHANG Juan ZHANG rui wang College of Information Science and Engineering Northeastern University State Key Laboratory of Synthetical Automation for Process Industries Northeastern University

This paper is dedicated to addressing the time-varying output formation-containment tracking(TVOFCT) problem for heterogeneous linear multiagent systems(MASs) with multiple types of disturbances under directed communication *** agents are divided into tracking leaders,formation leaders,and *** the output space,the formation leaders are required to form an expected geometric formation while tracking the tracking leader,and the followers are required to enter the convex hull spanned by formation ***,a disturbance observer is designed to observe the disturbance with deterministic ***,by combining adaptive technology with event-triggered technology,an independent fully distributed dynamic event-triggered(FDDET) compensator is designed to estimate the state of the tracking *** main advantages of this compensator lie in the following three aspects:(1) the adaptive weight does not increase unboundedly;(2) the interval time between events is expanded;(3) the design does not rely on any global *** to the design of this compensator,an independent FDDET convex hull observer is further designed to observe the convex hull spanned by formation ***,based on the designed disturbance observer,compensator,and convex hull observer,the adaptive disturbance rejection control input which can make the MASs achieve TVOFCT is ***,a numerical simulation is provided to clearly verify the validity of the theoretical results.

关键词： formation-containment tracking disturbance rejection multiagent systems fully distributed control dynamic event-triggered control

Enhancing Evolutionary Algorithms With Pattern Mining for Sparse Large-Scale Multi-Objective Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1786-1801页

作者： Sheng Qi rui wang Tao Zhang Weixiong Huang Fan Yu Ling wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China College of Systems Engineering National University of Defense TechnologyChangsha 410073and also with the Xiangjiang LaboratoryChangsha 410205China College of Transportation and Engineering Central South UniversityChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China

Sparse large-scale multi-objective optimization problems(SLMOPs)are common in science and ***,the large-scale problem represents the high dimensionality of the decision space,requiring algorithms to traverse vast expanse with limited computational ***,in the context of sparse,most variables in Pareto optimal solutions are zero,making it difficult for algorithms to identify non-zero variables *** paper is dedicated to addressing the challenges posed by *** start,we introduce innovative objective functions customized to mine maximum and minimum candidate *** substantial enhancement dramatically improves the efficacy of frequent pattern *** this way,selecting candidate sets is no longer based on the quantity of nonzero variables they contain but on a higher proportion of nonzero variables within specific ***,we unveil a novel approach to association rule mining,which delves into the intricate relationships between non-zero *** novel methodology aids in identifying sparse distributions that can potentially expedite reductions in the objective function *** extensively tested our algorithm across eight benchmark problems and four real-world *** results demonstrate that our approach achieves competitive solutions across various challenges.

关键词： Evolutionary algorithms pattern mining sparse large-scale multi-objective problems(SLMOPs) sparse large-scale optimization.

Modeling of Rectangular Microchannel Heat Sink with Non-Uniform Channels and Multi-Objective Optimization

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Journal of Thermal Science 2024年第5期33卷 1701-1711页

作者： SHANG Xueshuo wang Yixin LI Qingwen wang rui CUI Zheng SHAO Wei Institute of Advanced Technology Shandong UniversityJi'nan 250014China Institute of Thermal Science and Technology Shandong UniversityJi'nan 250014China Shandong Institute of Advanced Technology Ji'nan 250100China

Rectangular microchannel heat sinks(MCHS)are widely used to cool high-heat-flux electronic ***,previous studies focused mainly on MCHS with uniform channels(UCs).This study considers a microchannel heat sink with non-uniform channels(NUCs).A mathematical model is developed based on energy equations and the Darcy flow *** expressions for total thermal resistance and coolant pressure drop are derived using the thermoelectric *** and numerical simulations are performed to verify the mathematical *** non-uniformity increases,total coolant pressure drop decreases but at the cost of higher thermal *** overall performance of NUCs is better than that of UCs because of their lower ratio of pumping power to cooling *** transfer performance of NUCs changes little for more than 120 channels and depends mainly on channel arrangement.A multi-objective optimization is conducted to minimize the thermal resistance and pumping power of an *** optimal NUC saves 64%pumping power compared with a conventional UC for the total thermal resistance of 0.1℃/W,indicating that the use of non-uniform channels could be very helpful to reduce the flow resistance of MCHS.

关键词： microchannel heat sink non-uniform channel mathematical model multi-objective optimization