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Noninvasive beam diagnosis based on the TM_(010)mode

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Nuclear Science and Techniques 2024年第7期35卷 115-125页

作者： Chuang-Ye Song Wen-Hui huang Department of Engineering Physics Tsinghua University BeijingBeijing100084China of Education Beijing100084China

A resonant cavity based on the TM_(010)mode is an effective tool for noninvasive beam characterization. This technique has the advantages of a high signal-to-noise ratio, compact structure, and is related to multiple parameters compared with other beam monitors. In this study, high-precision measurements of the bunch charge, arrival time, bunch length, and energy parameters based on the TM_(010)mode are discussed. A cavity beam arrival time monitor(BAM) utilizing a phase cavity has been widely used in many facilities. Regarding bunch-length measurements, the influence of the beam energy, beam offset,and longitudinal spectrum on the TM_(010)mode are carefully considered to reduce errors, and the theoretical resolution of two cavities with different frequencies is analyzed. Owing to the dependence of the beam velocity of the beam loss factor, this method can also be used for the detection low beam energy using two cavities with the same frequency but different cavity lengths. A set of three cavities with different lengths and frequencies of 1.902 and 11.424 GHz is presented for measuring the four aforementioned parameters.

关键词： TM_(010)mode Noninvasive diagnosis Beam length Low energy

Understanding the Low Predictability of the 2015/16 El Niño Event Based on a Deep Learning Model

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Advances in Atmospheric Sciences 2024年第7期41卷 1313-1325页

作者： Tingyu WANG Ping huang Xianke YANG Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China National Space Science Center Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070China

The 2015/16 El Niño event ranks among the top three of the last 100 years in terms of intensity,but most dynamical models had a relatively low prediction skill for this event before the summer ***,the attribution of this particular event can help us to understand the cause of super El Niño–Southern Oscillation events and how to forecast them *** present study applies attribute methods based on a deep learning model to study the key factors related to the formation of this event.A deep learning model is trained using historical simulations from 21 CMIP6 models to predict the Niño-3.4 *** integrated gradient method is then used to identify the key signals in the North Pacific that determine the evolution of the Niño-3.4 *** crucial signals are then masked in the initial conditions to verify their roles in the *** addition to confirming the key signals inducing the super El Niño event revealed in previous attribution studies,we identify the combined contribution of the tropical North Atlantic and the South Pacific oceans to the evolution and intensity of this event,emphasizing the crucial role of the interactions among them and the North *** approach is also applied to other El Niño events,revealing several new precursor *** study suggests that the deep learning method is useful in attributing the key factors inducing extreme tropical climate events.

关键词： ENSO attribution deep learning ENSO prediction extreme El Niño

Physiological and pathological functions of circular RNAs in the nervous system

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Neural Regeneration Research 2024年第2期19卷 342-349页

作者： Min Zhou Shi Li Chuan huang School of Life Sciences Chongqing UniversityChongqingChina

Circular RNAs(circRNAs)are a class of covalently closed single-stranded RNAs that are expressed during the development of specific cells and *** play crucial roles in physiological and pathological processes by sponging microRNAs,modulating gene transcription,controlling the activity of certain RNA-binding proteins,and producing functional peptides.A key focus of research at present is the functionality of circRNAs in the nervous system and several advances have emerged over the last 2 ***,the precise role of circRNAs in the nervous system has yet to be comprehensively *** this review,we first summarize the recently described roles of circRNAs in brain development,maturity,and ***,we focus on the involvement of circRNAs in various diseases of the central nervous system,such as brain cancer,chronic neurodegenerative diseases,acute injuries of the nervous system,and neuropathic pain.A better understanding of the functionality of circRNAs will help us to develop potential diagnostic,prognostic,and therapeutic strategies to treat diseases of the nervous system.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis brain development circRNAs neuropathic pain Parkinson’s disease

Analyses of Political Crisis Impact on Tourism:A Panel Counterfactual Approach with Internet Search Index

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Journal of Systems Science & Complexity 2024年第4期37卷 1581-1603页

作者： huang Bai SUN Yuying YANG Boyu School of Statistics and Mathematics Central University of Finance&EconomicsBeijing 102206China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Center for Forecasting Science Chinese Academy of SciencesBeijing 100190China School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China

Existing research has shown that political crisis events can directly impact the tourism ***,the current methods suffer from potential changes of unobserved variables,which poses challenges for a reliable evaluation of the political crisis *** paper proposes a panel counterfactual approach with Internet search index,which can quantitatively capture the change of crisis impacts across time and disentangle the effect of the event of interest from the *** also provides a tool to examine potential channels through which the crisis may affect tourist *** research empirically applies the framework to analyze the THAAD event on tourist flows from the Chinese Mainland to South *** highlight the strong and negative short-term impact of the political crisis on the tourists' intentions to visit a *** paper provides essential evidence to help decision-makers improve the management of the tourism crisis.

关键词： Composite search index counterfactual analysis political crisis search query data tourism demand

IMAGE SUPER-RESOLUTION RECONSTRUCTION BY HUBER REGULARIZATION AND TAILORED FINITE POINT METHOD

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Journal of Computational Mathematics 2024年第2期42卷 313-336页

作者： Wenli Yang Zhongyi huang Wei Zhu School of Mathematics China University of Mining and TechnologyXuzhou 221116China Department of Mathematics Tsinghua UniversityBeijing 100084China Department of Mathematics University of AlabamaTuscaloosaAL 35487USA

In this paper,we propose using the tailored finite point method(TFPM)to solve the resulting parabolic or elliptic equations when minimizing the Huber regularization based image super-resolution model using the augmented Lagrangian method(ALM).The Hu-ber regularization based image super-resolution model can ameliorate the staircase for restored *** employs the method of weighted residuals with collocation tech-nique,which helps get more accurate approximate solutions to the equations and reserve more details in restored *** compare the new schemes with the Marquina-Osher model,the image super-resolution convolutional neural network(SRCNN)and the classical interpolation methods:bilinear interpolation,nearest-neighbor interpolation and bicubic *** experiments are presented to demonstrate that with the new schemes the quality of the super-resolution images has been *** these,the existence of the minimizer of the Huber regularization based image super-resolution model and the convergence of the proposed algorithm are also established in this paper.

关键词： Image super-resolution Variational model Augmented Lagrangian methods Tailored finite point method

Phase-modulated multi-foci microscopy for rapid 3D imaging

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Photonics Research 2024年第7期12卷 1548-1555页

作者： WEIQI WANG LI GONG ZHIWEI huang Optical Bioimaging Laboratory Department of Biomedical EngineeringCollege of Design and EngineeringNational University of SingaporeSingapore 117576Singapore

3D imaging technology is pivotal in monitoring the functional dynamics and morphological alterations in living cells and ***,conventional volumetric imaging associated with mechanical z-scanning encounters challenges in limited 3D imaging speed with inertial ***,we present a unique phase-modulated multifoci microscopy (PM^(3)) technique to achieve snapshot 3D imaging with the advantages of extended imaging depths and adjustable imaging intervals between each focus in a rapid *** accomplish the tasks,we utilize a spatial light modulator (SLM) to encode the phases of the scattered or fluorescence light emanating from a volumetric sample and then project the multiple-depth images of the sample onto a single charge-coupled device camera for rapid 3D *** demonstrate that the PM^(3)technique provides~55-fold improvement in imaging depth in polystyrene beads phantom compared to the depth of field of the objective lens ***^(3)also enables the real-time monitoring of Brownian motion of fluorescent beads in water at a 15 Hz volume *** precisely manipulating the phase of scattered light on the SLM,PM^(3)can pinpoint the specific depth information in living zebrafish and rapidly observe the 3D dynamic processes of blood flow in the zebrafish *** work shows that the PM^(3)technique developed is robust and versatile for fast 3D dynamic imaging in biological and biomedical systems.

关键词： alterations scattered beads

Three-dimensional(3D)parametric measurements of individual gravels in the Gobi region using point cloud technique

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Journal of Arid Land 2024年第4期16卷 500-517页

作者： JING Xiangyu huang Weiyi KAN Jiangming College of Engineering Beijing Forestry UniversityBeijing 100083China Key Laboratory of State Forestry Administration on Forestry Equipment and Automation Beijing 100083China

Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed *** presence significantly influences the movement of sand and ***,the complex origins and diverse materials constituting the Gobi result in notable differences in saltation processes across various Gobi *** is challenging to describe these processes according to a uniform ***,it becomes imperative to articulate surface characteristics through parameters such as the three-dimensional(3D)size and shape of *** morphology information for Gobi gravels is essential for studying its genesis and sand *** enhance the efficiency and information yield of gravel parameter measurements,this study conducted field experiments in the Gobi region across Dunhuang City,Guazhou County,and Yumen City(administrated by Jiuquan City),Gansu Province,China in March 2023.A research framework and methodology for measuring 3D parameters of gravel using point cloud were developed,alongside improved calculation formulas for 3D parameters including gravel grain size,volume,flatness,roundness,sphericity,and equivalent grain *** multi-view geometry technology for 3D reconstruction allowed for establishing an optimal data acquisition scheme characterized by high point cloud reconstruction efficiency and clear ***,the proposed methodology incorporated point cloud clustering,segmentation,and filtering techniques to isolate individual gravel point *** point cloud algorithms,including the Oriented Bounding Box(OBB),point cloud slicing method,and point cloud triangulation,were then deployed to calculate the 3D parameters of individual *** systematic processes allow precise and detailed characterization of individual *** gravel grain size and volume,the correlation coefficients between point cloud and manual measurements all exceeded 0.9000,confirming the feasibility of the proposed methodol

关键词： Gobi gravels three-dimensional(3D)parameters point cloud 3D reconstruction Random Sample Consensus(RANSAC)algorithm Density-Based Spatial clustering of Applications with Noise(DBSCAN)

Decadal prediction skill for Eurasian surface air temperature in CMIP6 models

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Atmospheric and Oceanic Science Letters 2024年第1期17卷 9-13页

作者： Yanyan huang Ni huang Qianfei Zhao Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina Nansen–Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Dalian Meteorological Bureau of Liaoning Province DalianChina

评估CMIP6年代际预测试验对季节平均SAT的预测技巧的结果表明:模式不能有效预测冬季和秋季SAT的年代际变率.IPSL-CM6A-LR和多模式集合平均对于春季SAT展现了预测技巧,其中对于变率的预测技巧好于振幅的结果.基于蒙古和我国华北地区的显... 详细信息

评估CMIP6年代际预测试验对季节平均SAT的预测技巧的结果表明:模式不能有效预测冬季和秋季SAT的年代际变率.IPSL-CM6A-LR和多模式集合平均对于春季SAT展现了预测技巧,其中对于变率的预测技巧好于振幅的结果.基于蒙古和我国华北地区的显著预测技巧,模式对于夏季SAT表现出最佳的预测水平.与外部强迫相比,模式对于SAT的预测技巧可能来自初始化.模式中的一个明显系统性误差值得注意,即模式中冬季SAT的变率可以持续到其他季节,而在观测中其他季节的SAT变化与冬季SAT相对独立.

关键词：欧亚地表温度年代际预测 CMIP6 DCPP

A microphysical investigation of different convective cells during the precipitation event with sustained high-resolution observations

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Frontiers of Earth Science 2024年第2期18卷 279-295页

作者： Ziheng huang Zheng RUAN Debin SU State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China Key Laboratory of Atmospheric Sounding China Meteorological AdministrationChengdu 610225China

The growth and breakup processes of raindrops within a cloud influence the rain intensity and the sizes of raindrops on the *** Doppler velocity spectrum acquired by a vertically pointing radar(VPR)contains information on atmospheric turbulence and the size classification of falling *** this study,the four types of Convective Cells(CC)during precipitation events with more than 700 mm of precipitation in southern China are *** characteristics of four types of CCs correspond to the isolated convection,the early stage,the mature stage,and the decline stage of organizational convection,in that *** analysis using retrieval of vertical air motion(Vair)and raindrop evolution in clouds from Doppler velocity spectra collected by C-band VPR revealed the growth and breakup of falling raindrops with dynamic *** raindrops appear in the early stages and are accompanied by ice particles,which are impacted by the falling path᾽s *** aggregation,which is primarily related to the alternation of updraft and downdraft,accounts for the mature stage᾽s high efficiency of surface *** CCs in the decline stage originate from the shallow uplift in the weak and broad downdraft under conditions of enough water *** updraft dominates the stage of isolated *** of convective cells could be more accurately represented in model evaluations.

关键词： cloud microphysics convective systems convective cell vertically pointing radar observations Doppler velocity spectrum