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A Reverse Path Planning Approach for Enhanced Performance of Multi-Degree-of-Freedom Industrial Manipulators

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1357-1379页

作者： Zhiwei lin Hui Wang Tianding Chen Yingtao jiang Jianmei jiang Yingpin Chen Key Laboratory of Light Field Manipulation and System Integration Applications in Fujian Province School of Physics and Information EngineeringMinnan Normal UniversityZhangzhou363000China Department of Electrical and Computer Engineering University of NevadaLas Vegas89154USA College of Material Engineering Fujian Agriculture and Forestry UniversityFuzhou350000China

In the domain of autonomous industrial manipulators,precise positioning and appropriate posture selection in path planning are pivotal for tasks involving obstacle avoidance,such as handling,heat sealing,and *** Multi-Degree-of-Freedom(MDOF)manipulators offer kinematic redundancy,aiding in the derivation of optimal inverse kinematic solutions to meet position and posture requisites,their path planning entails intricate multiobjective optimization,encompassing path,posture,and joint motion *** satisfactory results in practical scenarios remains *** response,this study introduces a novel Reverse Path Planning(RPP)methodology tailored for industrial *** approach commences by conceptualizing the manipulator’s end-effector as an agent within a reinforcement learning(RL)framework,wherein the state space,action set,and reward function are precisely defined to expedite the search for an initial collision-free *** enhance convergence speed,the Q-learning algorithm in RL is augmented with ***,we formulate the cylindrical bounding box of the manipulator based on its Denavit-Hartenberg(DH)parameters and propose a swift collision detection ***,the motion performance of the end-effector is refined through a bidirectional search,and joint weighting coefficients are introduced to mitigate motion in high-power *** efficacy of the proposed RPP methodology is rigorously examined through extensive simulations conducted on a six-degree-of-freedom(6-DOF)manipulator encountering two distinct obstacle configurations and target *** results substantiate that the RPP method adeptly orchestrates the computation of the shortest collision-free path while adhering to specific posture constraints at the target ***,itminimizes both posture angle deviations and joint motion,showcasing its prowess in enhancing the operational performance of MDOF industrial manipulators.

关键词： Reverse path planning Dyna-Q bidirectional search posture angle joint motion

Time-dependent longitudinal responses of a shield tunnel induced by surcharge load:Theoretical prediction and analysis

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Underground Space 2024年第1期14卷 219-238页

作者： Fayun Liang Zhuwei jiang Qiang Yuan lin Li Rulu Wang Department of Geotechnical Engineering Tongji UniversityShanghai 200092China School of Highway Chang’an UniversityXi’an 710064China Shanghai Shentong Metro Group Limited Maintenance Center Shanghai 20070China

The surcharge load at the ground surface inevitably breaks the original equilibrium state between the underneath tunnel and the surrounding soil,which will impact the service performance of a subway *** paper presents a novel semi-analytical approach for assessing the time-dependent,longitudinal responses of a subway tunnel in soft soil strata induced by the surcharge *** solution is developed based on the framework of the classical"two-stage method"but innovatively incorporates the effects of ground stratification,the consolidation process,and the longitudinal stiffness reduction of the ***’s poroelastic theory in conjunction with the Laplace-Fourier transform technique is selected to model the deformation of the stratified ground,while the Timoshenko beam on a Pasternak foundation is employed to model the mechanical responses of the *** proposed semi-analytical solution is validated not only by comparison with benchmark solutions and a finite element model,but also by predicting a well-documented field *** analyses are conducted to investigate the effects of the elastic modulus and the permeability coefficient of the stratified ground on the longitudinal responses of the *** is expected that the proposed solution can serve as a useful tool for evaluating the effects of the surcharge load on the longitudinal responses of a subway tunnel.

关键词： Time-dependent Longitudinal responses Stratified ground Subway tunnels Ground surface surcharge Consolidation

Atomic-level unveiling secondary recrystallization enabled microand macroscopic polarization enhancement for piezophotocatalytic oxygen activation

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Nano Research 2024年第6期17卷 5040-5049页

作者： Kai lin Zijian Zhu Weiyi Ge Tianxing jiang Hongwei Huang Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Material Sciences and TechnologyChina University of Geosciences(Beijing)Beijing 100083China School of Chemistry Beihang UniversityBeijing 100191China

Piezoelectric semiconductors bear the bifunctional photocatalysis and piezocatalysis,while the absent or weak internal charge driving force severely restricts its catalytic *** polarization strategy is desirable,and particularly understanding its mechanism from a microscopic perspective remains ***,we report a secondary recrystallization approach to achieving the simultaneous micro-and macroscopic polarization enhancement on Bi2WO6 nanosheets for boosting piezo-photocatalytic oxygen activation,and unravel the mechanism at an *** secondary recrystallization process not only results in a strengthened distortion of[WO6]octahedra with distortion index enhancement by~20%for a single octahedron,but also enables lateral crystal growth of nanosheets along the ab plane(av.50 to 180 nm),which separately allows the rise in dipole moment of unit cell(e.g.,1.63 D increase along a axis)and the stacking of the distorted[WO6]octahedron to accumulate the unit cell dipole,collectively contributing to the considerably strengthened spontaneous polarization and ***,exposure of large-area{001}front facet enables more efficient capture and conversion of stress into ***,the well-recrystallized Bi2WO6 nanosheets exhibit considerably promoted piezo-photocatalytic reactive oxygen species generation,given the decreased specific surface *** work presents a feasible methodology to regulate inside-out polarization for guiding carriers transfer behavior,and may advance the solid understanding on the intrinsic mechanism.

关键词： secondary recrystallization piezo-photocatalytic oxygen activation octahedron distortion polar units stacking micro-and macroscopic polarization enhancement

Numerical simulation of the dynamic migration mechanism and prediction of saturation of tight sandstone oil

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Science China Earth Sciences 2024年第1期67卷 179-195页

作者： Gaohui CAO Mian lin Likuan ZHANG Lili JI Wenbin jiang Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

Quantitative characterization of tight sandstone oil migration and accumulation is an emerging research frontier in the field of oil and gas *** this study,a conceptual model containing multiple basic geological elements is developed,and a nonlinear seepage numerical model for tight sandstone oil migration and accumulation is *** effects of the slip effect,overpressure driving force,buoyancy,and capillary force on the migration and accumulation of tight oil are *** results showed that(1)the differences in oil migration and accumulation between tight and conventional reservoirs are reflected in the growth mode of oil saturation,distribution characteristics of oil and water,and extent of the effect of the formation dip angle;(2)the slip effect has a significant impact when the average pore throat radius is less than 150 nm and the overpressure driving force and capillary force are the main mechanical mechanisms controlling oil migration and accumulation in tight sandstone,while the coupling effect of buoyancy,capillary force,and overpressure driving force controls the upper and lower limits of oil ***,a dimensional and dimensionless identification chart for rapidly predicting the oil saturation of tight sandstone is proposed and verified using the measured *** study provides a basis for analyzing the migration and accumulation mechanisms of tight sandstone oil and a new approach for predicting oil ***,we developed digital and visual analysis methods for the migration results,enriching the expression of the dynamics of hydrocarbon accumulation.

关键词： Tight sandstone Migration and accumulation Dynamics Oil saturation Numerical simulation

Impedance Model for Instability Analysis of LCC-HVDCs Considering Transformer Saturation

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1309-1319页

作者： Qin jiang Ruiting Xu Baohong Li Xiang Chen yue Yin Tianqi Liu Frede Blaabjerg College of Electrical Engineering Sichuan UniversityChengdu 610065China Smart Grid Key Laboratory of Sichuan Province Chengdu 610065China Department of Energy Technology Aalborg UniversityAalborg 9920Denmark

In line commutated converter based high-voltage direct current(LCC-HVDC)transmission systems,the trans-former saturation can induce harmonic instability,which poses a serious threat to the safe operation of the power ***-ever,the nonlinear characteristics of the power grids introduced by the transformer saturation considerably limit the application of the conventional analysis *** address the issue,this paper derives a linear model for the transformer saturation caused by the DC current due to the converter ***-terwards,the nonlinear characteristics of power grids with the transformer saturation is described by a complex valued imped-ance *** on the derived impedance matrix,the sys-tem harmonic stability is analyzed and the mechanism of the transformer saturation induced harmonic instability is ***,the sensitivity analysis is conducted to find the key fac-tors that influence the system core saturation *** proposed impedance model is verified by the electromagnetic transient simulation,and the simulation results corroborate the effectiveness of the proposed impedance *** Termsline commutated converter based high voltage direct current(LCC-HVDC),transformer saturation,harmonic instability,impedance model.

关键词： line commutated converter based high voltage direct current(LCC-HVDC) transformer saturation harmonic instability impedance model

Advances in targeted therapy for human epidermal growth factor receptor 2 positive in advanced gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2318-2334页

作者： Ya-Kun jiang Wei Li Ying-Yang Qiu Meng yue Department of Gastroenterology Central Hospital Affiliated to Shandong First Medical UniversityJinan 250013Shandong ProvinceChina Health Management Center Central Hospital Affiliated to Shandong First Medical UniversityJinan 250013Shandong ProvinceChina Yong Loo lin School of Medicine National University of SingaporeSingapore 119077Singapore

Emerging therapeutic methods represented by targeted therapy are effective supplements to traditional first-line chemoradiotherapy *** epidermal growth factor receptor 2(HER2)is one of the most important targets in targeted therapy for gastric *** combined with chemotherapy has been used as the first-line treatment for advanced gastric *** safety and efficacy of pertuzumab and margetuximab in the treatment of gastric cancer have been ***,monoclonal antibodies,due to their large molecular weight,inability to penetrate the blood-brain barrier,and drug resistance,lead to decreased therapeutic efficacy,so it is necessary to explore the efficacy of other HER2-targeting therapies in gastric ***-molecule tyrosine kinase inhibitors,such as lapatinib and pyrrotinib,have the advantages of small molecular weight,penetrating the blood-brain barrier and high oral bioavailability,and are expected to become the drugs of choice for perioperative treatment and neoadjuvant therapy of gastric cancer after validation by large-scale clinical trials in the ***-drug conjugate,such as T-DM1 and T-DXd,can overcome the resistance of monoclonal antibodies despite their different mechanisms of tumor killing,and are a supplement for the treatment of patients who have failed the treatment of monoclonal antibodies such as ***,after more detailed stratification of gastric cancer patients,various gastric cancer drugs targeting HER2 are expected to play a more significant role.

关键词： Human epidermal growth factor receptor 2 Gastric cancer Targeted therapy Review

Efficient Spin-Flip between Charge-Transfer States for High-Performance Electroluminescence, without an Intermediate Locally Excited State

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Research 2024年第1期2023卷 339-349页

作者： Donghai Zhang Shanshan jiang Xiaodong Tao Fulin lin lingyi Meng Xu-lin Chen Can-Zhong Lu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China FuzhouFujian 350108China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamenFujian 361021China University of Chinese Academy of Sciences Beijing 100049China

Thermally activated delayed fluorescence(TADF)materials with both high photoluminescence quantum yield(PLQY)and fast reverse intersystem crossing(RISC)are strongly desired to realize efficient and stable organic light-emitting diodes(OLEDs).Control of excited-state dynamics via molecular design plays a central role in optimizing the PLQY and RISC rate of TADF materials but remains ***,3 TADF emitters possessing similar molecular structures,similar high PLQYs(89.5%to 96.3%),and approximate energy levels of the lowest excited singlet states(S_(1)),but significantly different spin-flipping RISC rates(0.03×10^(6) s^(−1) vs.2.26×10^(6) s^(−1))and exciton lifetime(297.1 to 332.8μs vs.6.0μs)were systematically synthesized to deeply investigate the feasibility of spin-flip between charge-transfer excited states(^(3)CT–^(1)CT)transition.

关键词： transition lifetime desired

Protein hydrogels for biomedical applications

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Biosurface and Biotribology 2024年第3期10卷 106-131页

作者： Xinyi Wang yue Hou Xiong Lu Chaoming Xie Yanan jiang Institute of Biomedical Engineering College of MedicineSouthwest Jiaotong UniversityChengduSichuanChina Key Lab of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengduSichuanChina Obesity and Metabolism Medicine-Engineering Integration Laboratory Department of General SurgeryThe Third People's Hospital of ChengduThe Affiliated Hospital of Southwest Jiaotong UniversityChengduSichuanChina

Hydrogels,characterised as highly hydrophilic three-dimensional polymer networks,have gained increasing attention due to their unique physicochemical properties,finding applications in various *** polymer hydrogels exhibit higher biocompatibility and biodegradability compared to traditional synthetic polymer ***,being the principal materials of natural polymer hydrogels,bear numerous modifiable functional *** resultant hydrogel possesses responsiveness,adjustable degradability,and underway as an excellent *** common raw materials used to construct protein hydrogels are *** terms of comparing natural polymer hydrogels with traditional synthetic polymer hydrogels,the authors conduct a detailed analysis and comparison,highlighting the advantages of natural polymer hydrogels in terms of biocompatibility and biodegradability,and summarising their *** authors also address the limitations of various protein hydrogels and list existing strengthening cross-linking strategies,proposing new insights to overcome the application limits of protein ***,the applications of protein hydrogels in drug delivery,biosensing,bio-inks and tissue engineering are *** authors conclude by summarising the current challenges faced by protein hydrogels and prospecting its future development.

关键词： biomaterials biomedical application

Recent advances in glycerol valorization through electrocatalytic methods

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Tungsten 2024年第4期6卷 696-710页

作者： Hao-Hai Dong Yu-Xin Zhu Yi-Gu Li Jia-Yan Liang Ya Tan Xin-yue Zhang Hao-Min jiang Liu lin Ze-Min Sun Center for Advanced Materials Research & College of Arts and Sciences Beijing Normal University Department of Chemistry University College London

The recent tremendous growth of biodiesel production from vegetable oils or waste fats has led to increased glycerol accumulation as a by-product of this *** sparked attention towards glycerol use and valorization of this largely available and cheap *** several methods for glycerol valorization,electrochemical glycerol oxidation reaction(EGOR)is an attractive alternative anodic reaction to oxygen evolution reaction for a variety of electrolytic synthesis,due to the low thermodynamic ***,the EGOR at the anode can be coupled with a cathodic hydrogen evolution reaction to achieve efficient energy conversion in an aqueous electrolytic *** review provides a comprehensive summary and critical analysis of glycerol electrochemical oxidation research during the last 5 *** review focuses on the recent development and prospects of electrochemical pathways(indirect or direct routes) for application in the *** particular,the recent development and prospects of using noble and non-noble group metal catalysts for glycerol electro-oxidation are ***,reaction product selectivity analysis and conversion efficiency are also highlighted.

关键词： Active oxygen species Electrocatalytic methods Glycerol Noble metal catalysts Non-noble metal catalysts