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Compliance motion control of the hydraulic dual-arm manipulator with adaptive mass estimation of unknown object

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Frontiers of Mechanical Engineering 2024年第1期19卷 35-52页

作者： Bolin SUN Min CHENG Ruqi ding Bing XU State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China Key Laboratory of Conveyance and Equipment(Ministry of Education) East China Jiaotong UniversityNanchang 330013China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Given the limited operating ability of a single robotic arm,dual-arm collaborative operations have become increasingly *** with the electrically driven dual-arm manipulator,due to the unknown heavy load,difficulty in measuring contact forces,and control complexity during the closed-chain object transportation task,the hydraulic dual-arm manipulator(HDM)faces more difficulty in accurately tracking the desired motion trajectory,which may cause object deformation or even *** overcome this problem,a compliance motion control method is proposed in this paper for the *** mass parameter of the unknown object is obtained by using an adaptive method based on velocity *** to the difficulty in obtaining the actual internal force of the object,the pressure signal from the pressure sensor of the hydraulic system is used to estimate the contact force at the end-effector(EE)of two hydraulic manipulators(HMs).Further,the estimated contact force is used to calculate the actual internal force on the ***,a compliance motion controller is designed for HDM closed-chain *** position and internal force errors of the object are reduced by the feedback of the position,velocity,and internal force errors of the object to achieve the effect of the compliance motion of the HDM,i.e.,to reduce the motion error and internal force of the *** required velocity and force at the EE of the two HMs,including the position and internal force errors of the object,are inputted into separate position *** addition,the position controllers of the two individual HMs are designed to enable precise motion control by using the virtual decomposition control ***,comparative experiments are carried out on a hydraulic dual-arm test *** proposed method is validated by the experimental results,which demonstrate improved object position accuracy and reduced internal force.

关键词： hydraulic dual-arm manipulator compliance motion control unknown object adaptive mass estimation nonlinear control

Late Mesoproterozoic to Early Neoproterozoic Tectonic Evolution of the SW Yangtze Block, South China: Evidence from U-Pb Geochronology and Lu-Hf Isotopes of detrital Zircons from Sedimentary Rocks

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Journal of Earth Science 2024年第3期35卷 812-827页

作者： Peiwen Liu Xiaozhong ding Yanxue Liu Jibiao Zhang Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China School of Civil and Hydraulic Engineering Xichang UniversityXichang 615000China

In situ zircon U-Pb geochronological and Lu-Hf isotope studies of detrital zircons from Late Mesoproterozoic to Early Neoproterozoic sedimentary units on the southwestern margin of the Yangtze Block have important implications for the tectonic evolution of the Yangtze *** Huili Group contains zircons whose ages are mainly Late Archean to Mesoproterozoic(2650-2450,2100-1800,and 1350-1150 Ma).The dengxiangying Group has one major age population of 1900-1600 Ma,and two subordinate age populations of 1350-1100 and 2300-2000 *** Group sedimentary rocks have a zircon age population mainly in the range of 970-850 Ma,contemporaneous with the ages of widespread arc-related magmatism in the western Yangtze *** these results with previous work,the Huili and dengxiangying groups were most likely deposited during ca.1160 to 1000 Ma in an intra-continental rift basin setting,while the Yanbian Group accumulated during>920 to 782 Ma in a back-arc basin setting at the southwestern margin of the Yangtze *** addition,all these results further suggest a tectonic transition from a continental rift basin to a convergent environment at the southwestern margin of the Yangtze Block at 1000-970 Ma.

关键词： Late Mesoproterozoic Early Neoproterozoic zircon U-Pb age Lu-Hf isotope southwestern Yangtze Block geochronology

Numerical analysis of geosynthetic-reinforced embankment performance under moving loads

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 682-696页

作者： Xuanming ding Jinqiao Zhao Qiang Ou Jianfei Liu College of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China China United Engineering Corporation Limited Hangzhou310052China

The performance of geosynthetic-reinforced embankments under traffic moving loads is always a hotspot in the geotechnical engineering field.A three-dimensional(3D)model of a geosynthetic-reinforced embankment without drainage consolidation was established using the finite element software *** this model,the traffic loads were simulated by two moving loads of rectangular pattern,and their amplitude,range,and moving speed were realized by a Fortran *** embankment fill was simulated by an equivalent linear viscoelastic model,which can reflect its *** geogrid was simulated by the truss element,and the geocell was simulated by the membrane *** elements were utilized to weaken the boundary effect caused by the model geometry at the *** of the established numerical model was conducted by comparing the predicted deformations in the cross-section of the geosynthetic-reinforced embankment with those from the existing *** this basis,the dynamic stress and strain distribution in the pavement structure layer of the geosynthetic-reinforced embankment under a moving load was also ***,a parametric study was conducted to examine the influences of the different types of reinforcement,overload,and the moving load velocity on the geosynthetic-reinforced embankment.

关键词： Geosynthetic-reinforced layer Numerical model Moving load Embankment deformation Stress

Long way up:rethink diseases in light of phase separation and phase transition

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Protein & Cell 2024年第7期15卷 475-492页

作者： Mingrui ding Weifan Xu Gaofeng Pei Pilong Li State Key Laboratory of Membrane Biology&Frontier Research Center for Biological Structure School of Life SciencesTsinghua UniversityBeijing 100084China Tsinghua-Peking Center for Life Sciences Beijing 100084China NuPhase Therapeutics Beijing 100083China

Biomolecular condensation, driven by multivalency, serves as a fundamental mechanism within cells, facilitating the formation of distinct compartments, including membraneless organelles that play essential roles in various cellular processes. Perturbations in the delicate equilibrium of condensation, whether resulting in gain or loss of phase separation, have robustly been associated with cellular dysfunction and physiological disorders. As ongoing research endeavors wholeheartedly embrace this newly acknowledged principle, a transformative shift is occurring in our comprehension of disease. Consequently, significant strides have been made in unraveling the profound relevance and potential causal connections between abnormal phase separation and various diseases. This comprehensive review presents compelling recent evidence that highlight the intricate associations between aberrant phase separation and neurodegenerative diseases, cancers, and infectious diseases. Additionally, we provide a succinct summary of current efforts and propose innovative solutions for the development of potential therapeutics to combat the pathological consequences attributed to aberrant phase separation.

关键词： multivalency compartments aberant phase separation therapeutics gain or loss of phase separation diseases

A review on g-C_(3)N_(4)decorated with silver for photocatalytic energy conversion

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Chinese Chemical Letters 2024年第2期35卷 187-196页

作者： Ziyu Pan Wufan ding Hanchun Chen Haodong Ji Eco-environment and Resource Efficiency Research Laboratory School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Artificial photocatalytic energy conversion is considered as the most potential strategy for solving the increasingly serious energy crisis and environmental pollution problems by directly capturing solar ***,high efficiency photocatalyst has drawn significant research attention in recent *** to the excellent electronic,optical,structural,and physicochemical performances,silver-based g-C_(3)N_(4)have become promising *** review emphasizes the recent progresses and challenges on g-C_(3)N_(4)decorated with silver for photocatalytic energy *** extensive use of g-C_(3)N_(4)decorated with silver in diverse photocatalytic reactions,including hydrogen evolution,pollutant degradation and carbon dioxide reduction,is also fully *** addition,we propose the perspectives of g-C_(3)N_(4)decorated with silver on photocatalytic *** hope that this review will shed some light on the photocatalytic energy conversion of g-C_(3)N_(4)decorated with silver.

关键词： g-C_(3)N_(4) Silver-modified g-C_(3)N_(4) Photocatalytic energy conversion H_(2)evolution Pollutant degradation CO_(2)reduction

A new mixed type crack propagation criterion in shale reservoirs

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Petroleum 2024年第1期10卷 85-92页

作者： Muru ding zhirong Jin Yanjun Zhang Jinghong Hu Beijing Key Laboratory of Unconventional Natural Gas Geology Evaluation and development Engineering China University of Geosciences Sinopec Jiangsu Oil Field Branch Oil & Gas Technology Research Institute Changqing Oilefiled CompanyPetroChina

Hydraulic fracturing is a mainstream technology for unconventional oil and gas reservoirs development all over the world. How to use this technology to achieve high-level oil and gas resource extraction and how to form complex fracture networks as hydrocarbon transportation channels in tight reservoirs, which depends to a large extent on the interaction between hydraulic and pre-existing cracks. For hydraulic fracturing of fractured reservoirs, the impact of natural fractures, perforation direction, stress disturbances, faults and other influencing factors will produce a mixed I&II mode hydraulic fracture. To forecast whether hydraulic fractures cross pre-existing fractures, according to elastic mechanics and fracture mechanics, a stress state of cracks under the combination of tensile(I) and shear(II) is presented. A simple mixed-mode I&II hydraulic fracture's crossing judgment criterion is established, and the propagation of hydraulic fractures after encountering natural fractures is analyzed. The results show that for a given approaching angle there exists a certain range of stress ratio when crossing occurs. Under high approaching angle and large stress ratio, it is likely that hydraulic cracks will go directly through pre-existing cracks. The reinitiated angle is always controlled within the range of approximately 30°among the main direction of penetration.

关键词： Crack propagation criterion Stress ratio Approaching angle Reinitiated angle Mechanical model

Stability of the Phase Separation State for Compressible Navier-Stokes/Allen-Cahn System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 45-74页

作者： Ya-zhou Chen Hakho Hong Xiao-ding Shi department of Mathematics College of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing100029China Institute of Mathematics State Academy of SciencesPyongyangKorea

This paper is concerned with the large time behavior of the Cauchy problem for Navier-Stokes/AllenCahn system describing the interface motion of immiscible two-phase flow in 3-D. The existence and uniqueness of global solutions and the stability of the phase separation state are proved under the small initial perturbations. Moreover, the optimal time decay rates are obtained for higher-order spatial derivatives of density,velocity and phase. Our results imply that if the immiscible two-phase flow is initially located near the phase separation state, then under small perturbation conditions, the solution exists globally and decays algebraically to the complete separation state of the two-phase flow, that is, there will be no interface fracture, vacuum, shock wave, mass concentration at any time, and the interface thickness tends to zero as the time t → +∞.

关键词： Navier-Stokes/Allen-Cahn system existence uniqueness large time behavior decay rate

A Survey on Type-3 Fuzzy Logic Systems and Their Control Applications

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1744-1756页

作者： Oscar Castillo Fevrier Valdez Patricia Melin Weiping ding Tijuana Institute of Technology/Tecnologico Nacional de Mexico Division of Graduate StudiesCalzada Tecnologico S/NTijuana 22414Mexico School of Information Science and Technology Nantong UniversityJiangsu 226019China

In this paper,we offer a review of type-3 fuzzy logic systems and their applications in *** main objective of this work is to observe and analyze in detail the applications in the control area using type-3 fuzzy logic *** this case,we review their most important applications in control and other related topics with type-3 fuzzy *** algorithms have been receiving increasing attention in control and for this reason a review in this area is *** paper reviews the main applications that make use of Intelligent Computing ***,type-3 fuzzy logic *** aim of this research is to be able to appreciate,in detail,the applications in control systems and to point out the scientific trends in the use of Intelligent Computing *** is done with the construction and visualization of bibliometric networks,developed with VosViewer Software,which it is a free Java-based program,mainly intended to be used for analyzing and visualizing bibliometric *** this tool,we can create maps of publications,authors,or journals based on a co-citation network or construct maps of keywords,countries based on a co-occurrence networks,research groups,etc.

关键词： Applications control systems optimization review type-3 fuzzy logic.

Recent progress of vaccines administration via microneedles for cancer immunotherapy

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Chinese Chemical Letters 2024年第3期35卷 96-103页

作者： Yuanzheng Chen Jiaojiao Zhu Jinsong ding Wenhu Zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China Key Laboratory of Biological Nanotechnology of National Health Commission Changsha 410008China

Therapeutic cancer vaccines have undergone a resurgence in the past *** of the high level of immune cell accumulation and abundant capillary lymphatic system in the dermis,percutaneous vaccination is considered to be an ideal treatment *** convenient administration,the recent development of microneedles(MNs)provides a safe,painless,and low-cost transdermal delivery strategy,which could bypass the first-pass metabolism of vaccines for enhanced stability and ***,the therapeutic effect of MNs-based cancer vaccines is not optimal,which is limited by the complex set of host,tumor,and environmental factors,as well as the limited vaccine loading ***,further improvements are still required to push their clinical *** this critical review,we deliberate on how to improve the therapeutic effect of MNs-based vaccines for cancer immunotherapy,summarize the recent advances in MNs-based cancer vaccination,and provide an overview of various design strategies and mechanisms for active or passive targeting delivery,aiming to develop safer,more effective,and more stable MNs-based cancer ***,we briefly describe the potential of vaccine platforms in combination with other therapies,suggest the need to design vaccines according to specific circumstances,and discuss the biosafety of repeated administration for enhancing clinical efficacy.

关键词： Transdermal delivery Microneedles Cancer vaccine Immunotherapy Nanoparticle Lymph node