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RMPC-Based Visual Servoing for Trajectory Tracking of Quadrotor UAVs With Visibility Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2027-2029页

作者： Qifan yang Huiping li School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

Dear Editor,This letter deals with the tracking problem of quadrotors subject to external disturbances and visibility constraints by designing a robust model predictive control(RMPC) scheme. According to the imagebase... 详细信息

关键词： Visual image visibility

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Three-Dimensional Sound Source Location Algorithm for Subsea Leakage Using Hydrophone

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China Ocean Engineering 2024年第2期38卷 326-337页

作者： li Hao-jie CAI Bao-ping YUAN Xiao-bing KONG Xiang-di liU Yong-hong Javed Akbar KHAN CHU Zheng-de yang chao TANG An-bang College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China Shenzhen Urban Public Safety Technology Institute Shenzhen 518000China Institute of Hydrocarbon Recovery Universiti Teknologi PETRONASBandar Seri IskandarPerak Darul Ridzuan 32610Malaysia

Leakages from subsea oil and gas equipment cause substantial economic losses and damage to marine ecosystem,so it is essential to locate the source of the ***,due to the complexity and variability of the marine environment,the signals collected by hydrophone contain a variety of noises,which makes it challenging to extract useful signals for *** solve this problem,a hydrophone denoising algorithm is proposed based on variational modal decomposition(VMD)with grey wolf ***,the average envelope entropy is used as the fitness function of the grey wolf optimizer to find the optimal solution for the parameters K andα.Afterward,the VMD algorithm decomposes the original signal parameters to obtain the intrinsic mode functions(IMFs).Subsequently,the number of interrelationships between each IMF and the original signal was calculated,the threshold value was set,and the noise signal was removed to calculate the time difference using the valid signal obtained by ***,the arrival time difference is used to locate the origin of the *** localization accuracy of the method in finding leaks is investigated experimentally by constructing a simulated leak test rig,and the effectiveness and feasibility of the method are verified.

关键词： grey wolf optimizer variational modal decomposition mean envelope entropy correlation coefficient time difference of arrival

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Low-Enthalpy and High-Entropy Polymer Electrolytes for li-Metal Battery

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Energy & Environmental Materials 2024年第1期7卷 95-103页

作者： Haitao Zhang Yuchen Wang Junfeng Huang Wen li Xiankan Zeng Aili Jia Hongzhi Peng Xiong Zhang Weiqing yang Key Laboratory of Advanced Technologies of Materials Ministry of Education School of Materials Science and Engineering Southwest Jiaotong University Institute of Electrical Engineering Chinese Academy of Sciences

Ionic-conductive solid-state polymer electrolytes are promising for the development of advanced lithium batteries yet a deeper understanding of their underlying ion-transfer mechanism is needed to improve *** we demonstrate the low-enthalpy and high-entropy(LEHE) electrolytes can intrinsically generate remarkably free ions and high mobility,enabling them to efficiently drive lithium-ion storage.

关键词： charge concentration gradient lithium dendrites lithium-metal battery low-enthalpy and high-entropy polymer electrolyte

An anti-collision algorithm for robotic search-and-rescue tasks in unknown dynamic environments

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 569-584页

作者： yang CHEN Dianxi SHI Huanhuan yang Tongyue li Zhen WANG School of Computer Science Peking UniversityBeijing 100871China Tianjin Artificial Intelligence Innovation Center Tianjin 300457China Intelligent Game and Decision Lab Beijing 100071China College of Computer National University of Defense TechnologyChangsha 410073China

This paper deals with the search-and-rescue tasks of a mobile robot with multiple interesting targets in an unknown dynamic *** problem is challenging because the mobile robot needs to search for multiple targets while avoiding obstacles *** ensure that the mobile robot avoids obstacles properly,we propose a mixed-strategy Nash equilibrium based Dyna-Q(MNDQ)***,a multi-objective layered structure is introduced to simplify the representation of multiple objectives and reduce computational *** structure divides the overall task into subtasks,including searching for targets and avoiding ***,a risk-monitoring mechanism is proposed based on the relative positions of dynamic *** mechanism helps the robot avoid potential collisions and unnecessary ***,to improve sampling efficiency,MNDQ is presented,which combines Dyna-Q and mixed-strategy Nash *** using mixed-strategy Nash equilibrium,the agent makes decisions in the form of probabilities,maximizing the expected rewards and improving the overall performance of the Dyna-Q ***,a series of simulations are conducted to verify the effectiveness of the proposed *** results show that MNDQ performs well and exhibits robustness,providing a competitive solution for future autonomous robot navigation tasks.

关键词： Search and rescue Reinforcement learning Game theory Collision avoidance Decision-making

A Facile li2TiO3 Surface Modification to Improve the Structure Stability and Electrochemical Performance of Full Concentration Gradient li-Rich Oxides

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Energy & Environmental Materials 2024年第3期7卷 45-52页

作者： Naifang Hu Yuan yang lin li Yuhan Zhang Zhiwei Hu Lan Zhang Jun Ma Guanglei Cui Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences Institute of Materials Science and Engineering Ocean University of China School of Future Technology University of Chinese Academy of Sciences Max Planck Institute for Chemical Physics of Solids CAS Key Laboratory of Green Process and Engineering Beijing Key Laboratory of Ionic Liquids Clean ProcessState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of Sciences Shandong Energy Institute

Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rate performance,whereas the high lithium residues on its surface impairs the structure stability and long'term cycle performance. Herein,a facile multifunctional surface modification method is implemented to eliminate surface lithium residues of full concentration gradient lithium-rich layered oxides by a wet chemistry reaction with tetrabutyl titanate and the post-annealing process. It realizes not only a stable li2TiO3coating layer with 3D diffusion channels for fast li+ions transfer,but also dopes partial Ti4+ions into the sub-surface region of full concentration gradient lithium-rich layered oxides to further strengthen its crystal structure. Consequently,the modified full concentration gradient lithium-rich layered oxides exhibit improved structure stability,elevated thermal stability with decomposition temperature from 289.57℃to321.72℃,and enhanced cycle performance (205.1 mAh g-1after 150 cycles)with slowed voltage drop （1.67 mV per cycle）. This work proposes a facile and integrated modification method to enhance the comprehensive performance of full concentration gradient lithium-rich layered oxides,which can facilitate its practical application for developing higher energy density lithium-ion batteries.

关键词： full concentration gradient lithium-rich layered oxides structure stability surface modification

Universal and efficient hybrid modeling and direct slicing method for additive manufacturing processes

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Advances in Manufacturing 2024年第2期12卷 300-316页

作者： Sen-lin Wang li-chao Zhang chao Cai Ming-Kai Tang Si Chen Jiang Huang Yu-Sheng Shi State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan430074People’s Republic of China School of Machinery and Automation Wuhan University of Science and TechnologyWuhan430081People’s Republic of China

Model design and slicing contour generation in additive manufacturing(AM)data processing face challenges in terms of efficiency and scalability when stereolithography files generated by complex functionally graded structures have millions of *** paper proposes a hybrid modeling and direct slicing method for AM to efficiently construct and handle complex three-dimensional(3D)*** 3D solids,including conformal multigradient structures,were uniformly described using a small amount of data via signed distance *** hybrid representations were quickly discretized into numerous disordered directed lines using an improved marching squares *** establishing a directional HashMap to construct the topological relationship between lines,a connecting algorithm with linear time complexity is proposed to generate slicing contours for *** method replaces the mesh reconstruction and Boolean operation stages and can efficiently construct complex conformal gradient models of arbitrary topologies through hybrid ***,the time and memory consumption of direct slicing are much lower than those of previous methods when handling hybrid models with hundreds of millions of faces after mesh reconstruction.

关键词： Additive manufacturing(AM) Hybrid modeling Direct slicing Signed distance field

Deep learning framework for comprehensive molecular and prognostic stratifications of triple-negative breast cancer

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Fundamental Research 2024年第3期4卷 678-689页

作者： Shen Zhao chao-yang Yan Hong Lv Jing-Cheng yang chao You Zi-Ang li Ding Ma Yi Xiao Jia Hu Wen-Tao yang Yi-Zhou Jiang Jun Xu Zhi-Ming Shao Key Laboratory of Breast Cancer in Shanghai Department of Breast SurgeryFudan University Shanghai Cancer CenterShanghai 200032China Institute for AI in Medicine School of Artificial IntelligenceNanjing University of Information Science and TechnologyNanjing 210044China Department of Pathology Fudan University Shanghai Cancer CenterShanghai 200032China Greater Bay Area Institute of Precision Medicine Guangzhou 511466China Department of Radiology Fudan University Shanghai Cancer CenterShanghai 200032China

Triple-negative breast cancer(TNBC)is the most challenging breast cancer *** stratification and target therapy bring clinical benefit for TNBC patients,but it is difficult to implement comprehensive molecular testing in clinical ***,using our multi-omics TNBC cohort(N=425),a deep learning-based framework was devised and validated for comprehensive predictions of molecular features,subtypes and prognosis from pathological whole slide *** framework first incorporated a neural network to decompose the tissue on WSIs,followed by a second one which was trained based on certain tissue types for predicting different ***-omics molecular features were analyzed including somatic mutations,copy number alterations,germline mutations,biological pathway activities,metabolomics features and immunotherapy *** was shown that the molecular features with therapeutic implications can be predicted including the somatic PIK3CA mutation,germline BRCA2 mutation and PD-L1 protein expression(area under the curve[AUC]:0.78,0.79 and 0.74 respectively).The molecular subtypes of TNBC can be identified(AUC:0.84,0.85,0.93 and 0.73 for the basal-like immune-suppressed,immunomodulatory,luminal androgen receptor,and mesenchymal-like subtypes respectively)and their distinctive morphological patterns were revealed,which provided novel insights into the heterogeneity of TNBC.A neural network integrating image features and clinical covariates stratified patients into groups with different survival outcomes(log-rank Plidated on the TNBC cases from TCGA(N=143)and appeared robust to the changes in patient *** potential clinical translation,we built a novel online platform,where we modularized and deployed our framework along with the validated *** can realize real-time one-stop prediction for new *** summary,using only pathological WSIs,our proposed framework

关键词： Triple-negative breast cancer Deep learning Digital pathology Patient stratification Online platform

Microstructure and property of laser additive manufactured alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si after aged at different temperatures

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Rare Metals 2024年第5期43卷 2275-2281页

作者： Guo-chao li Xu Cheng Hua-Ming Wang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar *** this study,the influence of aging temperatures(600,700 and 800°C)on microstructure and mechanical properties of titanium alloy Ti-6Al-2V-1.5Mo-0.5Zr-0.3Si was *** results indicate that after solid solution treatment at 970°C followed by water quenching,the alloy mainly consists of coarsening lamellar a phase in martensite α' *** at 600°C will not change the size of primary lamellar α phase but lead to huge amount of secondary a phases(α_(s))generating with very fine *** increasing the aging temperature,the number of α_(s) decreases but with coarsened *** aged at 800°C,the width of the asphase reaches 350 nm,almost 7 times wider than that aged at 600°*** changing size of α_(s) obviously influences the property of the *** fine α_(s) leads to high strength and microhardness but low plasticity,and specimen aged at 700°C with suitable assize has the best comprehensive properties.

关键词： α+βtitanium alloy Laser additive manufacturing Solid solution and aging treatment Microstructure Room temperature tensile property

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Functional characterization,structural basis,and protein engineering of a rare flavonoid 2′-O-glycosyltransferase from Scutellaria baicalensis

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3746-3759页

作者： Zilong Wang Xueqing Du Guo Ye Haotian Wang Yizhan liu Chenrui liu Fudong li HansÅgren yang Zhou Junhao li chao He De-An Guo Min Ye State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Anhui Key Laboratory of Modern Biomanufacturing and School of life Sciences Anhui UniversityHefei 230601China National Science Center for Physical Sciences at Microscale Division of Molecular&Cell Biophysics and School of life Sciences University of Science and Technology of ChinaHefei 230026China Department of Physics and Astronomy Uppsala UniversityUppsala SE-75120Sweden School of Pharmacy Jinan UniversityGuangzhou 510632China Shanghai Research Center for Modernization of Traditional Chinese Medicine Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China

Glycosylation is an important post-modification reaction in plant secondary metabolism,and contributes to structural diversity of bioactive natural *** plants,glycosylation is usually catalyzed by *** 2′-O-glycosides are rare ***,no UGTs have been reported,thus far,to specifically catalyze 2′-O-glycosylation of *** this work,UGT71AP2 was identified from the medicinal plant Scutellaria baicalensis as the first flavonoid 2′-*** could preferentially transfer a glycosyl moiety to 2′-hydroxy of at least nine flavonoids to yield six new *** of the 2′-O-glycosides showed noticeable inhibitory activities against cyclooxygenase *** crystal structure of UGT71AP2(2.15Å)was solved,and mechanisms of its regio-selectivity was interpreted by pKa calculations,molecular docking,MD simulation,MM/GBSA binding free energy,QM/MM,and hydrogen‒deuterium exchange mass spectrometry *** structure-guided rational design,we obtained the L138T/V179D/M180T mutant with remarkably enhanced regio-selectivity(the ratio of 7-O-glycosylation byproducts decreased from 48%to 4%)and catalytic efficiency of 2′-O-glycosylation(kcat/Km,0.23 L/(s·μmol),12-fold higher than the native).Moreover,UGT71AP2 also possesses moderate UDP-dependent de-glycosylation activity,and is a dual function *** work provides an efficient biocatalyst and sets a good example for protein engineering to optimize enzyme catalytic features through rational design.

关键词： Glycosyltransferase Regio-selectivity Crystal structure De-glycosylation Catalytic mechanisms