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IEEE Transactions on Artificial Intelligence 2023年第4期4卷 754-763页

作者： Wu, Guohua Fan, Mingfeng Shi, Jianmai Feng, Yanghe Central South University School of Traffic Transportation Engineering Changsha410073 China National University of Defense Technology Science and Technology on Information Systems Engineering Laboratory College of System Engineering Changsha410073 China National University of Defense Technology College of Systems Engineering Changsha410073 China

Coronavirus disease 2019 has brought a great challenge to the supply of daily necessities and medical items for home-quarantined people. Considering the unmanned operation, agility, and use of clean energy of drones, we propose a novel truck-and-drone coordinated delivery system that does not require direct human contact during the delivery process. All final deliveries are completed by the drone while the truck acts as a movable charging station and a carrier, so that the contagion risks are reduced. Moreover, we spilt the whole delivery problem into the customer-clustering problem and the routing problems of both the truck and the drone. An encoder-decoder framework combined with reinforcement learning is created to solve the routing problems without handcrafted designed heuristics. We design the different problem contexts specific to the truck routing problem and the drone routing problem. The experimental results show that the proposed approach has good generality and can consequently be applied to problems of different scales with high time efficiency. © 2020 IEEE.

关键词： Reinforcement learning

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Joint Vehicle Pairing, Spectrum Assignment and Power Control for Sum-Rate Maximization in NOMA-Based V2X Underlaid Cellular Networks

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IEEE Internet of Things Journal 2025年第12期12卷 22337-22349页

作者： Xue, Tong Zhang, Haixia Ding, Hui Yuan, Dongfeng Shandong University of Science and Technology College of Electronic and Information Engineering Shandong Qingdao266590 China Shandong Key Laboratory of Intelligent Communication and Sensing-Computing Integration Shandong Jinan250061 China Shandong University School of Control Science and Engineering Shandong Jinan250061 China

Vehicle-to-everything (V2X) underlaid cellular networks in underlaid mode suffers catastrophic co-channel interference caused by spectrum sharing, results in a reduced system sum-rate. To cope with this, this work studies a social-mobility-aware non-orthogonal multiple access (NOMA)-enabled V2X underlaid cellular network to mitigate the co-channel interference and improve the sum-rate. By jointly optimizing vehicle pairing and resources, a sum-rate maximization problem is formulated under the diverse quality of service requirements of both cellular and vehicular users. The formulated problem is proved to be a non-deterministic polynomial-time (NP)-hard problem, and is difficult to solve. As an alternative, we propose a NOMA-based joint vehicle pairing, spectrum assignment and power control algorithm (NOMA-JVP-SA-PCA), with which the original problem is decomposed into two disjoint subproblems, i. e., 1) joint vehicle pairing and spectrum assignment subproblem, and 2) power control subproblem. Dealing the first subproblem, we propose a heuristic social-mobility-aware vehicle pairing algorithm (HSMA-VPA) and a revised Kuhn-munkres-based spectrum assignment algorithm (KM-SAA) to acquire the vehicle pairing and spectrum assignment solutions. Then, solving the second subproblem, a closed-form power solution is obtained utilizing a three-dimensional geometric power control approach (3D-PCA). Finally, we solve the original problem through an iterative method. Simulation results show that the proposed NOMA-JVP-SA-PCA effectively enhances the sum-rate and outperforms the baseline algorithms around 24%-53% within a specific range. © 2014 IEEE.

关键词： Polynomial approximation

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Laser polishing of a high-entropy alloy manufactured by selective laser melting

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Frontiers of Mechanical engineering 2024年第5期19卷 73-86页

作者： Xiaojun TAN Haibing XIAO Zihong WANG Wei ZHANG Zhijuan SUN Xuyun PENG Zhongmin LIU Liang GUO Qingmao ZHANG Intelligent Manufacturing and Equipment School Shenzhen Institute of Information TechnologyShenzhen 518172China Sino-German Intelligent Manufacturing School Shenzhen City PolytechnicShenzhen 518116China Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Industrial Ultrashort Pulse Laser Technology Shenzhen 518055China College of Materials Science and Engineering Chongqing UniversityChongqing 400045China

The selective laser melting(SLM)technique applied to high-entropy alloys(HEAs)has attracted considerable attention in recent ***,its practical application has been restricted by poor surface *** this study,the capability of laser polishing on the rough surface of a Co-free HEA fabricated using SLM was *** show that the initial SLM-manufactured(as-SLMed)surface of the Co-free HEA,with a roughness exceeding 3.0μm,could be refined to less than 0.5μm by laser ***,the microstructure,microhardness,and wear resistance of the laser-polished(LP-ed)zone were *** indicate that compared with the microhardness and wear resistance of the as-SLMed layer,those of the LP-ed layer decreased by 4%and 11%,respectively,because of the increase in grain size and reduction of the BCC *** study shows that laser polishing has an excellent application prospect in surface improvement of HEAs manufactured by SLM.

关键词： laser polishing selective laser melting high-entropy alloy surface roughness mechanical performance

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Optimal Tracking Neuro-Control of Continuous Stirred Tank Reactor systems: A Dynamic Event-Driven Approach

IEEE Transactions on Artificial Intelligence

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IEEE Transactions on Artificial Intelligence 2024年第5期5卷 2117-2126页

作者： Yang, Xiong Zhou, Yingjiang Tianjin University Tianjin Key Laboratory of Intelligent Unmanned Swarm Technology and System School of Electrical and Information Engineering Tianjin300072 China Nanjing University of Posts and Telecommunications College of Automation and College of Artificial Intelligence Nanjing210023 China

It is often challenging to design an optimal tracking controller for the continuous stirred tank reactor (CSTR) system due to its nonlinear nature and physical limitations. This article presents a dynamic event-driven optimal tracking neruo-control scheme for the CSTR system with asymmetric input constraints. Initially, an improved nonquadratic cost function is introduced for the CSTR system to tackle asymmetric control restrictions. Then, a dynamic event-driven mechanism together with the event-driven Hamilton-Jacobi-Bellman equation (ED-HJBE) is proposed. To solve the ED-HJBE, a critic neural network (CNN) is constructed within the critic learning framework. The CNN's weight vector is tuned by combining the gradient descent method and the concurrent learning technique. After that, uniform ultimate boundedness of the tracking error and the CNN's weight estimation error is assured based on the Lyapunov method. Finally, experiment studies are conducted to validate the present optimal tracking neuro-control strategy. © 2023 IEEE.

关键词： Reinforcement learning

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Carrier and microstructure tuning for improving the thermoelectric properties of Ag_(8)SnSe_(6)via introducing SnBr_(2)

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Journal of Advanced Ceramics 2022年第7期11卷 1144-1152页

作者： Zhonghai YU Xiuxia WANG Chengyan LIU Yiran CHENG Zhongwei ZHANG Ruifan SI Xiaobo BAI Xiaokai HU Jie GAO Ying PENG Lei MIAO Guangxi Key Laboratory of Information Materials Electronical Information Materials and Devices Engineering Research Center of Ministry of EducationSchool of Materials Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China

The argyrodite compounds(2 A(12)/B X6 m n n^(m+)+--(Am+=Li^(+),Cu^(+),and Ag^(+);Bn^(+)=Ga^(3+),Si^(4+),Ge^(4+),Sn^(4+),P^(5+),and As^(5+);and X^(2−)=S^(2−),Se^(2−),or Te^(2−)))have attracted great attention as excellent thermoelectric(TE)materials due to their extremely low lattice thermal conductivity(κl).Among them,Ag_(8)SnSe_(6)-based TE materials have high potential for TE ***,the pristine Ag_(8)SnSe_(6)materials have low carrier concentration(<1017 cm^(−3)),resulting in low power *** this study,a hydrothermal method was used to synthesize Ag_(8)SnSe_(6)with high purity,and the introduction of SnBr_(2)into the pristine Ag_(8)SnSe_(6)powders has been used to simultaneously increase the power factor and decrease the thermal conductivity(κ).On the one hand,a portion of the Br−ions acted as electrons to increase the carrier concentration,increasing the power factor to a value of~698 mW·m^(−1)·K^(−2)at 736 *** the other hand,some of the dislocations and nanoprecipitates(SnBr_(2))were generated,resulting in a decrease ofκl(~0.13 W·m^(−1)·K^(−1))at 578 *** a result,the zT value reaches~1.42 at 735 K for the sample Ag8Sn1.03Se5.94Br0.06,nearly 30%enhancement in contrast with that of the pristine sample(~1.09).The strategy of synergistic manipulation of carrier concentration and microstructure by introducing halogen compounds could be applied to the argyrodite compounds to improve the TE properties.

关键词： Ag_(8)SnSe_(6) thermoelectric(TE)performance lattice thermal conductivity SnBr_(2) introduction hydrothermal method

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High performance carrier stored trench bipolar transistor with dual shielding structure

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Chinese Physics B 2023年第3期32卷 576-582页

作者：张金平邓浩楠朱镕镕李泽宏张波 State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China(UESTC)Chengdu 610054China Institute of Electronic and Information Engineering of UESTC in Guangdong Dongguan 523808China

We propose a novel high performance carrier stored trench bipolar transistor(CSTBT)with dual shielding structure(DSS-CSTBT).The proposed DSS-CSTBT features a double trench structure with different trench profiles in the surface,in which a shallow gate trench is shielded by a deep emitter trench and a thick oxide layer under *** with the conventional CSTBT(con-CSTBT),the proposed DSS-CSTBT not only alleviates the negative impact of the shallow gate trench and highly doped CS layer on the breakdown voltage(BV),but also well reduces the gate-collector capacitance CGC,gate charge Q_(G),and turn-off loss E_(OFF)of the ***,lower turn-on loss E_(ON)and gate drive loss E_(DR)are also *** results show that with the same CS layer doping concentration N_(CS)=1.5×10^(16)cm^(-3),the BV increases from 1312 V of the con-CSTBT to 1423 V of the proposed DSS-CSTBT with oxide layer thickness under gate(T_(og2))of 1μ***,compared with the con-CSTBT,the C_(GC)at V_(CE)of 25 V and miller plateau charge(Q_(GC))for the proposed DSS-CSTBT with T_(og2)of 1μm are reduced by 79.4%and 74.3%,*** the VGEincreases from 0 V to 15 V,the total QGfor the proposed DSS-CSTBT with T_(og2)of 1μm is reduced by 49.5%.As a result,at the same on-state voltage drop(V_(CEON))of 1.55 V,the E_(ON)and E_(OFF)are reduced from 20.3 mJ/cm^(2)and 19.3 mJ/cm^(2)for the con-CSTBT to8.2 mJ/cm^(2)and 9.7 mJ/cm^(2)for the proposed DSS-CSTBT with T_(og2)of 1μm,*** proposed DSS-CSTBT not only significantly improves the trade-off relationship between the V_(CEON)and E_(OFF)but also greatly reduces the E_(ON).

关键词： carrier stored trench bipolar transistor(CSTBT) dual shielding structure gate-collector capacitance power loss

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Deciphering decadal urban ozone trends from historical records since 1980

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National science Review 2024年第11期11卷 117-129页

作者： Haolin Wang Xiao Lu Paul I.Palmer Lin Zhang Keding Lu Ke Li Tatsuya Nagashima Ja-Ho Koo Hiroshi Tanimoto Haichao Wang Meng Gao Cheng He Kai Wu Shaojia Fan Yuanhang Zhang School of Atmospheric Sciences Sun Yat-sen University and Key Laboratory of Tropical Atmosphere-Ocean System Ministry of Education Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the Pearl River Estuary Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) School of Geo Sciences University of Edinburgh National Centre for Earth Observation University of Edinburgh Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking University State Key Joint Laboratory of Environmental Simulation and Pollution Control The State Environmental Protection Key Laboratory of Atmospheric Ozone Pollution ControlCollege of Environmental Sciences and Engineering Peking University Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science &Technology National Institute for Environmental Studies Department of Atmospheric Sciences Yonsei University Department of Geography Hong Kong Baptist University Department of Civil and Environmental Engineering University of California

Ozone pollution is a major environmental threat to human health. Timely assessment of ozone trends is crucial for informing environmental policy. Here we show that for the most recent decade（2013–2022） in the northern hemisphere, warm-season（April–September） mean daily 8-h average maximum ozone increases much faster in urban regions with top ozone levels(mainly in the North China Plain, 1.2 ± 1.3 ppbv year-1) than in other, low-ozone regions(0.2 ± 0.9 ppbv year-1). These trends widen the ozone differences across urban regions, and increase extreme pollution levels and health threats from a global perspective. Comparison of historical trends in different urban regions reveals that ozone increases in China during 2013–2022 differ in magnitude and mechanisms to historical periods in other regions since *** reflects a unique chemical environment characterized by exceptionally high nitrogen oxides and aerosol concentrations, where reducing ozone precursor emissions leads to substantial ozone *** increase in China has slowed down in 2018–2022 compared to 2013–2017, driven by ongoing emission reductions, but with ozone-favorable weather conditions. Historical ozone evolution in Japan and South Korea indicates that ozone increases should be suppressed with continuous emission *** temperature and associated wildfires have also reversed ozone decreases in the USA and Europe,with anthropogenic ozone control slowing down in recent decades.

关键词： air quality surface ozone trends

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Photoreduction adjusted surface oxygen vacancy of Bi_(2)MoO_(6) for boosting photocatalytic redox performance

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Frontiers of Chemical science and engineering 2023年第12期17卷 1937-1948页

作者： Tie Shi Hailong Jia Yanmei Feng Bo Gong Daimei Chen Yu Liang Hao Ding Kai Chen Derek Hao Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing 100083China School of Materials Science and Technology Shenyang University of Chemical TechnologyShenyang 110142China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoringand Pollution Control School of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China Centre for Technology in Water and Wastewater(CTWW) School of Civil and Environmental EngineeringUniversity of Technology Sydney(UTS)NSW 2007Australia

In this study, Bi_(2)MoO_(6) with adjustable rich oxygen vacancies was prepared by a novel and simple solvothermal-photoreduction method which might be suitable for a large-scale production. The experiment results show that Bi_(2)MoO_(6) with rich oxygen vacancies is an excellent photocatalyst. The photocatalytic ability of BMO-10 is 0.3 and 3.5 times higher than that of the pristine Bi_(2)MoO_(6) for Rhodamine B degradation and Cr(VI) reduction, respectively. The results display that the band energy of the samples with oxygen vacancies was narrowed and the light absorption was broadened. Meanwhile, the efficiency of photogenerated electron-holes was increased and the separation and transfer speed of photogenerated carriers were improved. Therefore, this work provides a convenient and efficient method to prepare potential adjustable oxygen vacancy based photocatalysts to eliminate the pollution of dyes and Cr(VI) in water.

关键词： Bi_(2)MoO_(6) oxygen vacancies photoreduction Cr(VI) RhB

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Simultaneously optimizing exciton diffusion length and nonradiative energy loss in organic solar cells via ternary strategy

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science China Chemistry 2024年第9期67卷 3004-3011页

作者： Huanxiang Jiang Hao Lu Zezhou Liang Yonghai Li Guangliu Ran Chenyu Han Yuqiang Liu Hongxiang Li Xichang Bao Zhishan Bo College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao 266071China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China Key Laboratory for Physical Electronics and Devices of the Ministry of Education&Shaanxi Key Lab of Photonic Technique for InformationSchool of Electronics Science&EngineeringFaculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum StudiesBeijing Normal UniversityBeijing 100875China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Laboratory of Solar Energy Shandong Energy InstituteQingdao 266101China

Significant nonradiative energy loss and short exciton diffusion length in organic solar cells(OSCs)are two major obstacles to achieving state-of-the-art *** is crucial to conduct a study on the intensive mechanism and improvement strategies for future breakthroughs in the efficiency of *** this work,nonradiative energy loss and exciton diffusion length are optimized simultaneously by incorporating a guest acceptor(LA15)to construct ternary OSC(D18:L8-BO:LA15).Firstly,LA15 exhibits excellent compatibility with the host acceptor L8-BO,and effectively improves the fluorescence quantum efficiency(FLQY),resulting in suppressed non-radiative energy ***,LA15 effectively prolongs the fluorescent lifetime of the acceptor phase from 0.85 to 1.12 ns,leading to larger exciton diffusion length,which is beneficial for reducing geminate ***,the addition of LA15 optimizes the crystallinity of the active layer with amplified charge transport *** a result,the optimized D18:L8-BO:LA15 device achieves ultralow nonradiative energy loss of 0.18 e V and improved fill factor(FF)with high efficiency up to 19.13%.These results highlight the crucial roles of regulating FLQYand exciton lifetime in achieving highefficiency OSCs.

关键词： organic solar cells nonradiative energy loss exciton lifetime exciton diffusion length

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A Numerical Calculation Algorithm of the Inclination Function Based on the Representation of SO(3) Group

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 137-148页

作者： Yu-xiao Wei Wen-lin Tang Department of Geophysics School of Geology Engineering and GeomaticsChang’An UniversityXi’an710064China Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing100190China

In the determination of the Earth gravity field in satellite geodesy, the inclination functions represent the projection of data observed along the orbital plane of a satellite orbit into the sphere in the terrestial reference frame. The inclination functions in this work is studied from a group theoretical perspective. The inclination functions are proved to generate a representation of the SO(3) group. An orthogonal relation of the inclination functions is derived and some recurrence relations for the inclination functions are given, based on which an algorithm to calculate the inclination functions is proposed.

关键词： SO(3)group inclination function satellite geodesy representation of SO(3)

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