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Nano Research 2024年第6期17卷 5179-5187页

作者： Jinlei Qin Rui wang Zilong Yuan pei Xiao Deli wang Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Lithium-sulfur(Li-S)batteries have been considered as promising energy storage systems due to the merits of high energy density and low ***,the lithium polysulfides(LiPSs)diffusion and sluggish redox kinetics hamper t... 详细信息

关键词： Li-S batteries nitrogen-doped carbon confinement oxygen vacancies bidirectional Li_(2)S redox

Permanent lining castable with low bulk density and thermal conductivity:bauxite castable for tundish obtained by adding pearlescent sand

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Journal of Iron and Steel Research International 2024年第3期31卷 634-646页

作者： Yi wang Jian Yang Bao wang Hai-jun Zhang Juan Han pei-yan pei Wen-long Lv Jian-an Zhou The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Wuhan Research Institute of Metallurgical Construction MCCWuhan 430081HubeiChina

The low thermal conductivity and light mass of castables for tundish permanent linings are crucial for minimizing the heat loss of molten *** consideration of the low bulk density and thermal conductivity of pearlescent sand,the thermal insulation performance of castables was attempted to be improved by adding pearlescent *** sand was modified to prevent the strength of its porous structure from *** modification mechanism of pearlescent sand and the effect of pearlescent sand on the performance of bauxite castables were *** results suggested that the addition of the modified pearlescent sand significantly raised the apparent porosity and decreased the bulk density of bauxite *** 1000℃,the bulk density of more than 60%of the modified pearlescent sand-bauxite castable was only 2.03 g/cm^(3).The mechanical properties and thermal shock resistance of the modified pearlescent sand-bauxite castable were inferior to those of conventional bauxite castable but were adequate to meet the use conditions of casta-bles for tundish permanent *** high temperatures of 200-800℃,the thermal conductivity of more than 60%of the modified pearlescent sand-bauxite castable was smaller than that of conventional bauxite *** addition of the modified pearlescent sand can greatly reduce the thermal conductivity and bulk density of bauxite castable.

关键词： Pearlescent sand-Hydrophobic modification Bauxite castable Thermal insulation performance Mechanical property

Multiple-stage spatial-temporal cooperative guidance without time-to-go estimation

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Chinese Journal of Aeronautics 2024年第9期37卷 399-416页

作者： Chunyan wang Weilin wang Wei DONG Jianan wang fang DENG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China National Key Lab of Autonomous Intelligent Unmanned Systems Beiing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

This paper investigates the spatial-temporal cooperative guidance problem for multiple flight vehicles without relying on time-to-go ***,a two-stage cooperative guidance strategy,namely the cooperative guidance and the Proportional Navigation Guidance(PNG)stage strategy,is developed to realize the spatial-temporal constraints in two *** the former stage,two controllers are designed and superimposed to satisfy both impact time consensus and impact angle *** the convergent conditions are satisfied,the flight vehicles will switch to the PNG stage to ensure zero miss *** further extend the results to three dimensions,a planar pursuit guidance stage is additionally imposed at the beginning of *** to the inde-pendence of time-to-go estimation,the proposed guidance strategy possesses great performance in satisfying complex spatial-temporal constraints even under flight speed ***,several numerical simulations are implemented to verify the effectiveness and advantages of the proposed results under different scenarios.

关键词： Cooperative guidance Guided missiles Impact time consensus Impact angle constraint Spatial-temporal cooperative guidance

A novel triple periodic minimal surface-like plate lattice and its data-driven optimization method for superior mechanical properties

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 217-238页

作者： Yanda wang Yanping LIAN Zhidong wang Chunpeng wang Daining fang State Key Laboratory for Turbulence and Complex Systems&Center for Applied Physics and Technology College of EngineeringPeking UniversityBeijing 100871China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

Lattice structures can be designed to achieve unique mechanical properties and have attracted increasing attention for applications in high-end industrial equipment,along with the advances in additive manufacturing(AM)*** this work,a novel design of plate lattice structures described by a parametric model is proposed to enrich the design space of plate lattice structures with high connectivity suitable for AM *** parametric model takes the basic unit of the triple periodic minimal surface(TPMS)lattice as a skeleton and adopts a set of generation parameters to determine the plate lattice structure with different topologies,which takes the advantages of both plate lattices for superior specific mechanical properties and TPMS lattices for high connectivity,and therefore is referred to as a TPMS-like plate lattice(TLPL).Furthermore,a data-driven shape optimization method is proposed to optimize the TLPL structure for maximum mechanical properties with or without the isotropic *** this method,the genetic algorithm for the optimization is utilized for global search capability,and an artificial neural network(ANN)model for individual fitness estimation is integrated for high efficiency.A set of optimized TLPLs at different relative densities are experimentally validated by the selective laser melting(SLM)fabricated *** is confirmed that the optimized TLPLs could achieve elastic isotropy and have superior stiffness over other isotropic lattice structures.

关键词： lattice structure triple periodic minimal surface(TPMS) plate lattice structural optimization machine learning

A Distortion Self-Calibration Method for Binocular High Dynamic Light Adjusting and Imaging System Based on Digital Micromirror Device

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2036-2038页

作者： pei Wu Yanjie wang Honghai Sun Zhuoman Wen University of Chinese Academy of Sciences Beijing 100049and NIO Inc.Shanghai 200000China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical design of the system, the causes of the distortion are given and a distortion model is established. Then, a quick and accurate self-calibration method is designed. The experiments indicate that the method can calibrate the two image sensors of the system at the same time,the average pixel deviation of the calibrated system is less than 0.5pixels and the maximum deviation is less than 1 pixel.

关键词： Dynamic system deviation

Graph neural network-based scheduling for multi-UAV-enabled communications in D2D networks

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Digital Communications and Networks 2024年第1期10卷 45-52页

作者： pei Li Lingyi wang Wei Wu Fuhui Zhou Baoyun wang Qihui Wu Nanjing University of Posts and Telecommunications Nanjing210023China Nanjing University of Aeronautics and Astronautics Nanjing210016China

In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)*** objective is to maximize the total transmission rate of Downlink Users(DUs).Meanwhile,the Quality of Service(QoS)of all D2D users must be *** comprehensively considered the interference among D2D communications and downlink *** original problem is strongly non-convex,which requires high computational complexity for traditional optimization *** to make matters worse,the results are not necessarily globally *** this paper,we propose a novel Graph Neural Networks(GNN)based approach that can map the considered system into a specific graph structure and achieve the optimal solution in a low complexity ***,we first construct a GNN-based model for the proposed network,in which the transmission links and interference links are formulated as vertexes and edges,***,by taking the channel state information and the coordinates of ground users as the inputs,as well as the location of UAVs and the transmission power of all transmitters as outputs,we obtain the mapping from inputs to outputs through training the parameters of *** results verified that the way to maximize the total transmission rate of DUs can be extracted effectively via the training on ***,it also shows that the performance of proposed GNN-based method is better than that of traditional means.

关键词： Unmanned aerial vehicle D2 Dcommunication Graph neural network Power control Position planning

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氮在不同生态特征沟渠系统中的衰减规律研究

水利学报 2007年第9期38卷 1135-1139页

作者：王沛芳王超胡颖水文水资源与水利工程科学国家重点实验室江苏南京210098 浅水湖泊综合治理与资源开发教育部重点实验室江苏南京210098

在分析河流水体中氮的迁移转化过程和衰减机理的基础上,选择太湖流域宜兴大浦镇境内林渠和赵渠两条农田排水沟为观测现场,开展氮在不同生态特征沟渠中的衰减规律研究,分析不同尺度和水动力条件对水体中氮衰减规律的影响,探讨水体中氮截... 详细信息

在分析河流水体中氮的迁移转化过程和衰减机理的基础上,选择太湖流域宜兴大浦镇境内林渠和赵渠两条农田排水沟为观测现场,开展氮在不同生态特征沟渠中的衰减规律研究,分析不同尺度和水动力条件对水体中氮衰减规律的影响,探讨水体中氮截留、吸附、转化的内部机理。研究结果表明,沟渠的生态特征,特别是几何尺度和水动力特性与水体中总氮衰减过程紧密相关;沟渠流速越大,水体中总氮衰减率越大;水生植物密度越大总氮衰减率也越大。

关键词：氮生态特征衰减效率林渠赵渠

Spatial-temporal patterns and evolution of carbon storage in China's terrestrial ecosystems from 1980 to 2020

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Science China Earth Sciences 2024年第10期67卷 3270-3287页

作者： Shaojian wang Shijie ZHOU Chuanglin fang School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Analyzing the changes in carbon storage in terrestrial ecosystems caused by land use changes is a crucial part of exploring the carbon cycle. In addition, enhancing carbon storage in terrestrial ecosystems is an effective and environmentally friendly measure to sequester anthropogenic carbon emissions, which is significant for achieving carbon neutrality and curbing global climate change. This paper uses land use data and carbon density tables with the In VEST model to obtain a carbon storage distribution map of China. It further applies land use response elasticity coefficients, Theil index multi-stage nested decomposition, and spatial autocorrelation analysis to examine the spatial-temporal patterns, causes of changes, and evolution characteristics of carbon storage in terrestrial ecosystems from 1980 to 2020. The results show that the temporal changes in China's carbon storage generally present an inverted S-curve, with an initial rapid decline followed by a slower decrease. Spatially, it features high levels in the northeast, low levels in the northwest, and a uniform distribution in the central and southern *** disturbance of land use type changes on terrestrial ecosystem carbon storage has been effectively mitigated. The significant reduction in grassland area in the Southwest region is the main source of carbon storage loss during the study period, and the encroachment of construction land on arable land in large urban agglomerations is one of the important causes of carbon storage loss. The Theil index multi-stage nested decomposition results indicate that the overall difference in carbon storage in China has decreased, while differences among cities within provinces and among counties within cities have increased. The influence of natural factors on the distribution of carbon storage is weakening, whereas the impact of human activities is becoming more profound, enhancing its influence on the spatial distribution of carbon storage in China. From 198

关键词： Terrestrial ecosystem carbon storage Carbon density Land use change InVEST model Spatiotemporal pattern

Implementation of integrated nonlocal sensing for object shape and rotational speed

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 6-12页

作者： Zhenyu Guo Yunlong wang Zehong Chang Jiawei wang Junliang Jia pei Zhang Ministry of Education Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic DevicesSchool of PhysicsXi’an Jiaotong UniversityXi’an 710049China

The expeditious acquisition of information pertaining to objects through the utilization of quantum technology has been a perennial issue of *** far,the efficient utilization of information from dynamic objects with limited resources remains a significant ***,we realize a nonlocal integrated sensing of the object's amplitude and phase information by combining digital spiral imaging with the correlated orbital angular momentum *** amplitude information is utilized for object identification,while the phase information enables us to determine the rotational *** demonstrate the nonlocal identification of a rotating object's shape,irrespective of its rotational symmetry,and introduce the concept of the correlated rotational Doppler effect,establishing a fundamental connection between this effect and the classical rotational Doppler effect,i.e.,that both rely on extracting crucial information from the spiral spectrum of *** present study highlights a promising pathway towards the realization of quantum remote sensing and imaging.

关键词： digital spiral imaging orbital angular momentum correlated rotational Doppler effect

Anthropogenic warming is a key climate indicator of rising urban fire activity in China

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National Science Review 2024年第5期11卷 110-120页

作者： Qichao Yao Dabang Jiang Ben Zheng Xiaochun wang Xiaolin Zhu Keyan fang Lamei Shi Zhou wang Yongli wang Linhao Zhong Yanyan pei Amy Hudson Shuai Xu Maowei Bai Xinyan Huang Valerie Trouet National Institute of Natural Hazards Ministry of Emergency Management of China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education School of Forestry Northeast Forestry University Laboratory of Tree-Ring Research University of Arizona Institute of Atmospheric Physics Chinese Academy of Sciences Department of Statistics Colorado State University Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic University Key Laboratory of Humid Subtropical Eco-Geographical Process (MOE) College of Geographic Sciences Fujian Normal University Department of Building Environment and Energy Engineering The Hong Kong Polytechnic University

China, one of the most populous countries in the world, has suffered the highest number of natural disaster-related deaths from fire. On local scales, the main causes of urban fires are anthropogenic in ***, on regional to national scales, little is known about the indicators of large-scale co-varying urban fire activity in China. Here, we present the China Fire History Atlas(CFHA), which is based on 19 947documentary records and represents fires in urban areas of China over the twentieth century(1901–1994).We found that temperature variability is a key indicator of urban fire activity in China, with warmer temperatures being correlated with more urban fires, and that this fire–temperature relationship is seasonally and regionally explicit. In the early twentieth century, however, the fire–temperature relationship was overruled by war-related fires in large urban areas. We further used the fire–temperature relationship and multiple emissions scenarios to project fire activity across China into the twenty-first century. Our projections show a distinct increase in future urban fire activity and fire-related economic loss. Our findings provide insights into fire–climate relationships in China for densely-populated areas and on policy-relevant time scales and they contribute spatial coverage to efforts to improve global fire models.

关键词： fire–climate interactions global warming fire history network urban fires fire management