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Climatic implications in earlywood and latewood width indices of Chinese pine in north central China

Journal of Forestry Research 2024年第3期35卷 143-153页

作者： Kaixuan Yang Junzhou Zhang Haowen fan Yuan Yan College of Geographic Sciences Qinghai Normal UniversityXining 810016People's Republic of China Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Xining 810016People's Republic of China Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730030People's Republic of China Gansu Liancheng Forest Ecosystem Field Observation and Research Station Lanzhou UniversityLanzhou 730333People's Republic of China School of Geography and Information Engineering University of GeoscienceWuhan 430074People's Republic of China

Latewood width(LWW)indices of trees are considered a reliable proxy of summer precipitation in the Northern ***,the strong coupling and high correlation between earlywood width(EWW)and LWW indices often prevent registration of climate signals of the LWW *** this study,328-year-long earlywood width and latewood width chronologies were developed from Chinese pine at two sites in the Hasi Mountains,north central *** climate responses of these chronologies were analyzed and the LWW index used to derive sum-mer precipitation *** analyses showed that LWW was particularly influenced by earlywood growth and recorded stronger climate signals of the previous year as EWW,rather than those of the current year with infrequent summer climate ***,after removing the effect of earlywood growth using a simple regression model,the adjusted LWW chronology(LWW_(adj))showed a strong relationship with July precipitation in dry *** suggests that the LWW_(adj) chronology has the potential to be used to investigate long-term variability in summer precipitation in drought-limited regions.

关键词： Dendroclimatology Latewood width Climate response Summer precipitation Earlywood effect

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Entangled photons enabled ultrafast stimulated Raman spectroscopy for molecular dynamics

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Light(Science & Applications) 2024年第8期13卷 1615-1622页

作者： Jiahao Joel fan Zhe-Yu Ou Zhedong Zhang Department of Physics City University of Hong KongKowloonHong Kong SARChina City University of Hong Kong Shenzhen Research InstituteShenzhenGuangdongChina

Quantum entanglement has emerged as a great resource for studying the interactions between molecules and *** propose a new scheme of stimulated Raman scattering with entangled photons.A quantum ultrafast Raman spectroscopy is developed for condensed-phase molecules,to monitor the exciton populations and *** results are obtained,showing an entanglement-enabled time-frequency scale not attainable by classical *** Raman signal presents an unprecedented selectivity of molecular correlation functions,as a result of the Hong-Ou-Mandel *** work suggests a new paradigm of using an unconventional interferometer as part of spectroscopy,with the potential to unveil advanced information about complex materials.

关键词： materials spectroscopy selectivity

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Probability-Enhanced Anchor-Free Detector for Remote-Sensing Object Detection

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Computers, Materials & Continua 2024年第6期79卷 4925-4943页

作者： Chengcheng fan Zhiruo fang Innovation Academy for Microsatellites of CAS Shanghai201210China Shanghai Engineering Center for Microsatellites Shanghai201210China College of Artificial Intelligence Nanjing Agricultural UniversityNanjing210095China

Anchor-free object-detection methods achieve a significant advancement in field of computer vision,particularly in the realm of real-time ***,in remote sensing object detection,anchor-free methods often lack of capability in separating the foreground and *** paper proposes an anchor-free method named probability-enhanced anchor-free detector(ProEnDet)for remote sensing object ***,a weighted bidirectional feature pyramid is used for feature ***,we introduce probability enhancement to strengthen the classification of the object’s foreground and *** detector uses the logarithm likelihood as the final score to improve the classification of the foreground and background of the *** is verified using the DIOR and NWPU-VHR-10 *** experiment achieved mean average precisions of 61.4 and 69.0 on the DIOR dataset and NWPU-VHR-10 dataset,*** achieves a speed of 32.4 FPS on the DIOR dataset,which satisfies the real-time requirements for remote-sensing object detection.

关键词： Object detection anchor-free detector probabilistic fully convolutional neural network remote sensing

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Multi-UAV cooperative maneuver decision-making for pursuitevasion using improved MADRL

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Defence Technology（防务技术） 2024年第5期35卷 187-197页

作者： Delin Luo Zihao fan Ziyi Yang Yang Xu School of Aerospace Engineering Xiamen UniversityXiamen 361102China School of Civil Aviation Northwestern Polytechnical UniversityXi'an 710072China

Aiming at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-agent deep reinforcement learning(MADRL) is proposed. In this method, an improved Comm Net network based on a communication mechanism is introduced into a deep reinforcement learning algorithm to solve the multi-agent problem. A layer of gated recurrent unit(GRU) is added to the actor-network structure to remember historical environmental states. Subsequently,another GRU is designed as a communication channel in the Comm Net core network layer to refine communication information between UAVs. Finally, the simulation results of the algorithm in two sets of scenarios are given, and the results show that the method has good effectiveness and applicability.

关键词： Reinforcement learning UAV Maneuver decision GRU Cooperative control

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Separation of La(Ⅲ),Ce(Ⅳ)and Ca(Ⅱ)from bastnaesite using acidic phosphonic chitosan and rotating disk membrane

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Journal of Rare Earths 2024年第5期42卷 995-1000,I0007页

作者： Dandan Lu Wenhui Li Linlin fan Yunren Qiu School of Chemistry and Chemical Engineering Central South UniversityChangsha410083China

The separation of rare earths is difficult due to their similar properties and the complex characteristics of associated vein o ***-ultrafiltration(CUF)and shear induced o rderly dissociation coupling with ultrafiltration(SIODUF)were used to separate metal ions(M,M=La(Ⅲ),Ce(Ⅳ)and Ca(Ⅱ))from simulated bastnaesite leaching solution using acidic phosphonic chitosan(aPCS)and rotating disk *** of simultaneous removal of metallic ions was investigated by CUF,and suitable conditions were obtained for C/M 10.0(mass ratio of complexant to metal ions)and pH *** shear stabilities of aPCS-M complexes were explored at different pH values and the results show that the complexes can dissociate at a certain rotational speed,the critical *** critical s hear rates of aPCS-La,aPCS-Ce and aPCS-Ca complexes at pH 5.0 were calculated as 1.42×10^(5).1.69×10^(5) and 9.75×10^(4) s^(-1),*** order of complexes shear stability is aPCS-Ca aPCS-La<*** high selective separation of M and regeneration of aPCS were achieved by SIODUF in the light of the difference of aPCSM complexes shear *** separation coefficientsβLa/Ce andβCa/La reach 31.2 and 53.9,respectively.

关键词： Bastnaesite Rare earths Complexation-ultrafiltration Acidic phosphonic chitosan Rotating disk membrane

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Simultaneous enhancement of red luminescence and thermal stability of a novel red phosphor:A Li^(+)-Eu^(3+)co-occupied site strategy in BaAl_(2)Ge_(2)O_(8)lattices

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Journal of Rare Earths 2024年第10期42卷 1846-1854页

作者： Wei Zhang Changjian Wang Xusheng Qiao Xianping fan State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Ocean Academy Zhejiang UniversityZhoushan316021China

The rapid development of phosphor-converted white light emitting diodes(pc-WLEDs)requires new red phosphors with efficient and thermally stable luminescence for high-quality warm-white ***,it is still a challenge to discover red phosphors with facile synthesis,high internal quantum efficiency(IQE),excellent thermal stability and high color ***,a novel red-emitting Eu^(3+)activated barium dialuminum digermanate(BaAl_(2)Ge_(3)O_(8),EAGO)phosphor showing strong red emission at 610 nm was *** IQE is improved from 32.91%to 78.84%by employing a charge compensation *** lithium-ion co-dop ed BAGO:Eu^(3+)phosphor exhibits a nearly twofold increase in integral photoluminescence(PL)intensity and the high color purity reaches 94.17%.Impressively,the PL intensity of the BAGO:Eu^(3+),Li^(+)phosphor drops by only 2.6%at 150℃of that at room ***,the pc-WLED using the red BAGO:Eu^(3+),Li^(+)phosphor exhibits white light with the chromaticity coordinate of(0.3515,0.3495),a high color-rendering index of 92 and a low correlated color temperature of 4746 *** these results manifest that BAGO:Eu^(3+),Li^(+)phosphor is a suitable red phosphor for nearultraviolet(NUV)chip-based pc-WLEDs.

关键词： BaAl_(2)Ge_(2)O_(8):Eu^(3+) Red phosphor Charge compensation High quantum efficiency Excellent thermal stability Rare earths

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Characterization and identification towards dynamic-based electrical modeling of lithium-ion batteries

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Journal of Energy Chemistry 2024年第5期92卷 738-758页

作者： Chuanxin fan Kailong Liu Yaxing Ren Qiao Peng School of Automation Nanjing Institute of TechnologyNanjing 211167JiangsuChina School of Control Science and Engineering Shandong UniversityJinan 250100ShandongChina School of Engineering University of LincolnLincoln LN67TSUK Information Technology Analytics&Operations GroupQueen’s University BelfastBelfast BT95EEUK

Lithium-ion batteries are widely recognized as a crucial enabling technology for the advancement of electric vehicles and energy storage systems in the *** design of battery state estimation and control algorithms in battery management systems is usually based on battery models,which interpret crucial battery dynamics through the utilization of mathematical ***,the investigation of battery dynamics with the purpose of battery system identification has garnered considerable attention in the realm of battery *** methods in terms of linear and nonlinear response of lithium-ion batteries have emerged as a prominent area of study in this *** review has undertaken an analysis and discussion of characterization methods,with a particular focus on the motivation of battery system ***,this work encompasses the incorporation of frequency domain nonlinear characterization methods and dynamics-based battery electrical *** aim of this study is to establish a connection between the characterization and identification of battery systems for researchers and engineers specialized in the field of batteries,with the intention of promoting the advancement of efficient battery technology for real-world applications.

关键词： Lithium-ion battery Battery dynamics Nonlinear characterization Nonlinear battery model

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AWells-Riley/based COVID-19 infectiousrisk assessment model combining both short rangeandroom scale effects

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Building Simulation 2024年第1期17卷 93-111页

作者： Yinshuai Feng Yifan fan Xiaoyu Luo Jian Ge College of Civil Engineering and Architecture Zhejiang UniversityHangzhouChina Center for Balance Architecture Zhejiang UniversityHangzhouChina International Research Center for Green Building and Low-Carbon City International CampusZhejiang UniversityHainingChina

There is growing evidence of the high transmission potential of COVID-19 through virus-laden *** aerosols are inhaled in various concentrations,an overall assessment of transmission risks at different indoor scales is ***,a comprehensive risk assessment method that evaluates the direct link between short-range and room-scale zones is stl *** this paper,a risk assessment model combining both short-range and room-scale effects is developed to obtain effective reproduction number in confined indoor environments,called Turbulent Jet Wells Riley(TJWR)*** with the viral load data and aerosol generation data of different human respiratory activities,the Monte Carlo simulation method is applied to calculate the quanta emission rate,which further provides the input parameters of the TJWR *** known outbreaks(Hangzhou banquet hall X,Guangzhou restaurant Y,and Hong Kong restaurant Z,China)are chosen to validate the TJWR *** show that the TJWR model is more efficient than the original Wells-Riley *** average relative error of the TJWR model ranges between 9%and 44%,while for the Wells-Riley model,it ranges between 57%and 78%.The TJWR model also proves that infection risk assessments using the well-mixed assumption can systematically underestimate the transmission risk for those close to the ***,there is a significant positive linear correlation between the total number of exposed individuals at the short-range and the effective reproduction *** newly developed TJWR model has great potential for rapid and real-time overall airborne transmission risk assessment in buildings and cities.

关键词： COVID-19 airborne transmission infection risk Wells-Riley model Monte Carlo simulation

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Experimental investigation on the gravity driven discharge of cohesive particles from a silo with two outlets

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Particuology 2024年第6期89卷 11-21页

作者： Li Dai Zhulin Yuan Fengxian fan Conghui Gu School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai 200093China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China

An experimental study on the gravity driven discharge of cohesive particles from a silo with two outlets was *** discharge behaviors under the conditions that a single outlet was open and two outlets were open were investigated by varying the moisture content of the particles and the filling height of the particles in the *** results show that the discharge rate of the cohesive particles increases gradually at the beginning,then almost keeps constant,and finally drops *** discharge rate in case of two openings is around 1.1–1.6 times that in case of a single *** filling height leads to lower discharge rate in case of a single opening but results in higher discharge rate in case of two ***,the avalanche dynamics in case of a single opening was examined,and the mixing behavior of the cohesive particles was *** is observed that the discharge flow is promoted by the avalanche phenomenon in the silo,generating a general trend that the normalized mass of discharge increases with the filling height at higher moisture *** case of a single opening,the transition from mass flow to funnel flow favors the particle mixing,resulting in an increasing mixing index as the moisture content *** general,a better performance of mixing can be achieved in case of a single opening compared with in case of two *** study provides vital information for fundamental understanding of the gravity driven discharge of cohesive particles from the silo with multiple outlets.

关键词： Cohesive particles Moisture content Discharge rate Avalanche Mixing

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Evaluation of transmission risk of respiratory particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： Liangyu Zhu Xian Li Bujin Feng fan Liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor *** exhaled particles may be inhaled by the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains *** this study,the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent layout and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dynamics(CFD)

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