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Integrated Clustering and Routing Design and Triangle Path Optimization for UAV-Assisted Wireless Sensor Networks

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china Communications 2024年第4期21卷 178-192页

作者： Shao Liwei qian Liping Wu Mengru Wu Yuan College of Information Engineering Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Internet of Things for Smart City University of MacaoMacaoChina Department of Computer and Information science University of MacaoMacaoChina

With the development of the Internet of Things(IoT),it requires better performance from wireless sensor networks(WSNs),such as larger coverage,longer lifetime,and lower ***,a large amount of data generated from monitoring and long-distance transmission places a heavy burden on sensor nodes with the limited battery *** this,we investigate an unmanned aerial vehicles assisted mobile wireless sensor network(UAV-assisted WSN)to prolong the network lifetime in this ***,we use UAVs to assist the WSN in collecting *** the current UAV-assisted WSN,the clustering and routing schemes are determined ***,such a separate consideration might not maximize the lifetime of the whole WSN due to the mutual coupling of clustering and *** efficiently prolong the lifetime of the WSN,we propose an integrated clustering and routing scheme that jointly optimizes the clustering and routing *** the whole network space,it is intractable to efficiently obtain the optimal integrated clustering and routing ***,we propose the Monte-Las search strategy based on Monte Carlo and Las Vegas ideas,which can generate the chain matrix to guide the algorithm to find the solution *** point-to-point collection leads to long collection paths,so a triangle optimization strategy is then proposed that finds a compromise path to shorten the collection path based on the geometric distribution and energy of sensor *** avoid the coverage hole caused by the death of sensor nodes,the deployment of mobile sensor nodes and the preventive mechanism design are *** emergency data transmission mechanism is further proposed to reduce the latency of collecting the latency-sensitive data due to the absence of *** with the existing schemes,the proposed scheme can prolong the lifetime of the UAVassisted WSN at least by 360%,and shorten the collection path of UAVs by 56.24%.

关键词： Monte-Las search strategy triangle path optimization unmanned aerial vehicles wireless sensor networks

LEGENDRE-GAUSS-RADAU SPECTRAL COLLOCATION METHOD FOR NONLINEAR SECOND-ORDER INITIAL VALUE PROBLEMS WITH APPLICATIONS TO WAVE EQUATIONS

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Journal of Computational Mathematics 2024年第1期42卷 217-247页

作者： Lina Wang qian Tong Lijun Yi Mingzhu Zhang Department of Mathematics Shanghai Normal UniversityShanghai 200234China School of science Henan University of EngineeringZhengzhou 451191China

We propose and analyze a single-interval Legendre-Gauss-Radau(LGR)spectral collocation method for nonlinear second-order initial value problems of ordinary differential *** design an efficient iterative algorithm and prove spectral convergence for the single-interval LGR collocation *** more effective implementation,we propose a multi-interval LGR spectral collocation scheme,which provides us great flexibility with respect to the local time steps and local approximation ***,we combine the multi-interval LGR collocation method in time with the Legendre-Gauss-Lobatto collocation method in space to obtain a space-time spectral collocation approximation for nonlinear second-order evolution *** results show that the proposed methods have high accuracy and excellent long-time *** comparison between our methods and several commonly used methods are also provided.

关键词： Legendre-Gauss-Radau collocation method Second-order initial value problem Spectral convergence Wave equation

γ-Radiation synthesis of nanocrystalline nickel powder from nickel (Ⅱ ) -ammonia complex solution

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Chinese science Bulletin 1997年第8期42卷 644-648页

作者： ZHU Yingjie, qian Yitai and ZHANG Manwei1. Department of Applied Chemistry, university of science and technology of china, Hefei 230026, china 2. Structure Research Laboratory, university of science and technology of china, Hefei 230026, china Departnient of Applied Chemistry University of Scirnce and Technology of China Hefei China Structure Research I.aboratory University of Science and Technology of China Hefei China

NANOCRYSTALLINE nickel is very important for its applications in the fields such as catalysis andmagnetic *** usual method used for preparing nanocrystalline nickel is inert gas e-vaporation,which requires high ***,high temperature easily leads tothe growth or oxidation of nickel *** et *** the nickel microaggre-gates dispersed in solution produced by γ-irradiating a dilute solution of Ni2+

关键词： nickel nanocrystalline powder γ-radiation.

Proton‑Prompted Ligand Exchange to Achieve High‑Efficiency CsPbI_(3) Quantum Dot Light‑Emitting Diodes

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Nano-Micro Letters 2024年第6期16卷 53-62页

作者： Yanming Li Ming Deng Xuanyu Zhang Lei qian Chaoyu Xiang Laboratory of Advanced Nano‑Optoelectronic Materials and Devices Qianwan Institute of CNITECHNingbo 315300People’s Republic of China Division of Functional Materials and Nanodevices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Faculty of Electrical Engineering and Computer science Ningbo UniversityNingbo 315211ZhejiangPeople’s Republic of China university of Nottingham Ningbo china Ningbo 315100People’s Republic of China

CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting ***,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improvement of device *** in-situ ligand replacement and ligand exchange after synthesis were often difficult to ***,we proposed a new ligand exchange strategy using a proton-prompted insitu exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI_(3)*** exchange strategy maintained the size and morphology of CsPbI_(3)QDs and improved the optical properties and the conductivity of CsPbI_(3)QDs *** a result,high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45%and an operational half-life of 10.79 h.

关键词： CsPbI_(3) perovskite quantum dots Light-emitting diodes Ligand exchange Proton-prompted in-situ exchange

Robot trajectory planning for autonomous 3D reconstruction of cockpit in aircraft final assembly testing

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Chinese Journal of Aeronautics 2024年第3期37卷 332-350页

作者： Yanzhe WANG Zemin PAN qian YANG Changxi DENG Yanding WEI The State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China School of Information science and Engineering NingboTech UniversityNingbo 315100China AVIC Xi’an Aircraft Industry(Group)Company Ltd. Xi’an 710089China Key Laboratory of Advanced Manufacturing technology of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China

The trend towards automation and intelligence in aircraft final assembly testing has led to a new demand for autonomous perception of unknown cockpit operation scenes in robotic collaborative airborne system *** address this demand,a robotic automated 3D reconstruction cell which enables to autonomously plan the robot end-camera’s trajectory is developed for image acquisition and 3D modeling of the cockpit operation scene.A continuous viewpoint path planning algorithm is proposed that incorporates both 3D reconstruction quality and robot path quality into optimization *** metrics for viewpoint position paths and orientation paths are introduced together for the first time in 3D *** ensure safe and effective movement,two spatial constraints,Domain of View Admissible Position(DVAP)and Domain of View Admissible Orientation(DVAO),are implemented to account for robot reachability and collision *** using diffeomorphism mapping,the orientation path is transformed into 3D,consistent with the position *** orientation and position paths can be optimized in a unified framework to maximize the gain of reconstruction quality and path smoothness within DVAP and *** reconstruction cell is capable of automatic data acquisition and fine scene modeling,using the generated robot C-space *** and physical scene experiments have confirmed the effectiveness of the proposed method to achieve highprecision 3D reconstruction while optimizing robot motion quality.

关键词： Aircraft assembly testing Aircraft cockpit 3D modeling Camera viewpoint Robot trajectory planning

Joined AZ31B Magnesium Alloys with Ag Interlayer by Ultrasonic-Induced Transient Liquid Phase Bonding in Air

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1177-1185页

作者： qian Wang Peng Yu Haoran Lin Chongzhi Guo Xiaoqiang Hu Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China School of Rare Earths University of Science and Technology of ChinaHefei230026China Shenyang 7D New Materials Equipment Co.LTD. Shenyang110076China Shenyang National Laboratory of Materials science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

AZ31B magnesium alloys are commonly used in lightweight structures of automobile and aerospace *** this work,the ultrasonic-induced transient liquid phase bonding technique is deployed to joint AZ31B magnesium alloys at 490℃ with Ag interlayer in the *** effect of ultrasonic vibration on microstructure and mechanical properties of welding seam is *** vibration duration increases,the width of the welding seam increases firstly and then *** the ultrasound vibration sustained for one second,the eutectic reaction occurred in the contacting interface between Ag interlayer and the base metal AZ31B,resulting in formation of liquid phase and metallurgical *** the ultrasound vibration sustained for seven second,the width of the welding seam increased to a maximum of about 303.1μm and the average shear bond strength of the welding joint attained the peak value of about 66.87 *** the ultrasound vibration sustained over seven seconds,the liquid phase is gradually squeezed out and the width of the welding seam decreases.α-Mg and AgMg_(3) can be observed in the welding *** analysis shows thatα-Mg has a certain strengthening *** whole process of appearance,growth and integration ofα-Mg is analyzed.

关键词： Ultrasonic bonding Magnesium alloy Silver Microstructure Intermetallic compound

MAUN:Memory-Augmented Deep Unfolding Network for Hyperspectral Image Reconstruction

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1139-1150页

作者： qian Hu Jiayi Ma Yuan Gao Junjun Jiang Yixuan Yuan Electronic Information School Wuhan UniversityWuhan 430072China School of Computer science and technology Harbin Institute of TechnologyHarbin 150001China Department of Electronic Engineering Chinese University of Hong KongHong Kong 999077China

Spectral compressive imaging has emerged as a powerful technique to collect the 3D spectral information as 2D *** algorithm for restoring the original 3D hyperspectral images(HSIs)from compressive measurements is pivotal in the imaging *** approaches painstakingly designed networks to directly map compressive measurements to HSIs,resulting in the lack of interpretability without exploiting the imaging *** some recent works have introduced the deep unfolding framework for explainable reconstruction,the performance of these methods is still limited by the weak information transmission between iterative *** this paper,we propose a Memory-Augmented deep Unfolding Network,termed MAUN,for explainable and accurate HSI ***,MAUN implements a novel CNN scheme to facilitate a better extrapolation step of the fast iterative shrinkage-thresholding algorithm,introducing an extra momentum incorporation step for each iteration to alleviate the information ***,to exploit the high correlation of intermediate images from neighboring iterations,we customize a cross-stage transformer(CSFormer)as the deep denoiser to simultaneously capture self-similarity from both in-stage and cross-stage features,which is the first attempt to model the long-distance dependencies between iteration *** experiments demonstrate that the proposed MAUN is superior to other state-of-the-art methods both visually and *** code is publicly available at https://***/HuQ1an/MAUN.

关键词： Deep folding iteration

Disparity estimation for multi-scale multi-sensor fusion

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Journal of Systems Engineering and Electronics 2024年第2期35卷 259-274页

作者： SUN Guoliang PEI Shanshan LONG qian ZHENG Sifa YANG Rui Suzhou Automotive Research Institute Tsinghua UniversitySuzhou 215000China beijing Smarter Eye technology Co. Ltd.Beijing 100023China College of Artifical Intelligence Tianjin University of Science and TechnologyTianjin 300457China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Department of Precision Instrument Tsinghua UniversityBeijing 100084China

The perception module of advanced driver assistance systems plays a vital *** schemes often use a single sensor for data processing and environmental perception or adopt the information processing results of various sensors for the fusion of the detection *** paper proposes a multi-scale and multi-sensor data fusion strategy in the front end of perception and accomplishes a multi-sensor function disparity map generation scheme.A binocular stereo vision sensor composed of two cameras and a light deterction and ranging(LiDAR)sensor is used to jointly perceive the environment,and a multi-scale fusion scheme is employed to improve the accuracy of the disparity *** solution not only has the advantages of dense perception of binocular stereo vision sensors but also considers the perception accuracy of LiDAR *** demonstrate that the multi-scale multi-sensor scheme proposed in this paper significantly improves disparity map estimation.

关键词： stereo vision light deterction and ranging(LiDAR) multi-sensor fusion multi-scale fusion disparity map

Boosting oxygen vacancies by modulating the morphology of Au decorated In_(2)O_(3)with enhanced CO_(2)hydrogenation activity to CH_(3)OH

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Journal of Environmental sciences 2024年第6期140卷 91-102页

作者： Ruxian Hou Jiewen Xiao qian Wu Tianyu Zhang qiang Wang beijing Key Lab for Source Control technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China

CO_(2)hydrogenation to methanol has become one of the most promising ways for CO_(2)utilization,however,the CO_(2)conversion rate and methanol selectivity of this reaction still need to be improved for industrial *** we investigated the structure-activity relationship for CO_(2)conversion to methanol of In_(2)O_(3)-based catalysts by modulating morphology and decorating *** different Au/In_(2)O_(3)catalysts were prepared,their activity follow the sequence of Au/In_(2)O_(3)-nanosphere(Au/In_(2)O_(3)-NS)>Au/In_(2)O_(3)-nanoplate(Au/In_(2)O_(3)-NP)>Au/In_(2)O_(3)-hollow microsphere(Au/In_(2)O_(3)-HM).Au/In_(2)O_(3)-NS exhibited the best performance with good CO_(2)conversion of 12.7%,high methanol selectivity of 59.8%,and large space time yield of 0.32 g CH_(3)OH/(hr·gcat)at 300℃.The high performance of Au/In_(2)O_(3)-NS was considered as the presence of *** contributes to the creation of more surface oxygen vacancies,which further promoted the CO_(2)adsorption and facilitated CO_(2)activation to form the formate intermediates towards *** work clearly suggests that the activity of In_(2)O_(3)catalyst can be effective enhanced by structure engineering and Au decorating.

关键词： CO_(2)hydrogenation Methanol Au/In_(2)O_(3) Morphology Oxygen vacancies