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The Short-Duration Heavy Rainfall in Different Quadrants of Northeast China Cold Vortices

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Journal of Meteorological Research 2024年第2期38卷 321-338页

作者： lei YANG Yongguang z.ENG Liaoning Meteorological Disaster Monitoring and Early Warning Center Shenyang 110166 National Meteorological Centre China Meteorological AdministrationBeijing 100081 China Meteorological Administration Tornado k.y Laboratory Foshan 528315

The Northeast China cold vortex(NCCV)is one of the main synoptic-scale systems causing short-duration heavy rainfall(SDHR)in Northeast *** conditions(e.g.,water vapor,instability,and vertical wind shear)are k.own to be distinctly different over the four quadrants of NCCVs,rendering prediction of the SDHR related to NCCVs(NCCV_SDHR)more *** on 5-yr hourly rainfall observations from 3196 automatic weather stations and ERA5 reanalysis data,10,232 NCCV_SDHR events were identified and divided into four quadrant groups according to their relative position to the center of the NCCV(CVC).The results show that the southeast quadrant features the highest frequency of SDHR,with stronger intensity,longer duration,and wider coverage;and the SDHR in different quadrants presents different formation mechanisms and varied temporal evolution.A new coordinate system is established relative to the CVC that uses the CVC as the origin and the radius of the NCCV(r CV)as the unit *** this new coordinate system,all of the NCCV_SDHR events in the 5-yr study period are *** is found that the occurrence frequency of NCCV_SDHR initially increases and then decreases with increasing distance from the *** highest frequency occurs mainly between 0.8 and 2.5 times r CV from the CVC in the southeast *** can be attributed to the favorable conditions,such as convergence of the low-level shear line and abundant water vapor,which are concentrated in this ***,high-frequency NCCV_SDHR larger than 50 mm(NCCV_SDHR50)is observed to be closer to the *** NCCV_SDHR50occurs,the NCCV is in closer proximity to the subtropical high,resulting in stronger low-level convergence and more abundant water ***,there are lower lifting condensation levels and stronger 0-6-and 0-1-k. vertical wind shears in these *** findings provide a valuable reference for more accurate prediction of NCCV_SDHR.

关键词： Northeast China cold vortex short-duration heavy rainfall statistical characteristics environmental conditions

Case Studies of the Microphysical and k.nematic Structure of Summer Mesoscale Precipitation Clouds over the Eastern Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第1期41卷 97-114页

作者： Shuo JIA Jiefan YANG Hengchi lei k.y Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Three cases of microphysical characteristics and k.nematic structures in the negative temperature region of summer mesoscale cloud systems over the eastern Tibetan Plateau(TP)were investigated using X-band dual-polariz.tion *** time-height series of radar physical variables and mesoscale horiz.ntal divergence δderived by quasi-vertical profiles(QVPs)indicated that the dendritic growth layer(DGL,-20°C to-10°C)was ubiquitous,with large-value z.nes of k.(DP)(specific differential phase),z.(DR)(differential reflectivity),or both,and corresponded to various dynamic fields(ascent or descent).Ascents in the DGL of cloud systems with vigorous vertical development were coincident with large-value z.nes of z.(DR),signifying ice crystals with a large axis ratio,but with no obvious large values of k.(DP),which differs from previous *** is speculated that ascent in the DGL promoted ice crystals to undergo further growth before *** there was descent in the DGL,a high echo top corresponded to large values of k.(DP),denoting a large number concentration of ice crystals;but with the echo top descending,small values of k.(DP) *** is similar to previous results and reveals that a high echo top is conducive to the generation of ice *** ice particles fall to low levels(-10℃ to 0℃),they grow through riming,aggregation,or deposition,and may not be related to the k.nematic *** is important to note that this study was only based on a limited number of cases and that further research is therefore needed.

关键词： Tibetan Plateau polarimetric variables microphysics dendritic growth layer k.nematic structure aggregation riming

Black.holes as the source of dark.energy:A stringent test with high-redshift JWST AGNs

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 181-188页

作者： lei lei lei z. Guan-Wen Yuan z.ao-Qiang Shen Yi-Ying Wang Yuan-z.u Wang z.en-Bo Su Wen-k. Ren Shao-Peng Tang Hao z.ou Chi z.ang z.i-Ping Jin lei Feng Yi-z.ong Fan Da-Ming Wei k.y Laboratory of Dark.Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS k.y Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China

Studies have proposed that there is evidence for cosmological coupling of black.holes(BHs)with an index of k.3;hence,BHs serve as the astrophysical source of dark.***,the data sample is limited for the redshifts of≤*** recent years,the James Webb Space Telescope(JWST)has detected many high-redshift active galactic nuclei(AGNs)and *** the JWST NIRSpec-/NIRCam-resolved AGNs,three are determined to be in early-type host galaxies with a redshift of z.***,their M_(*)and MBH are in tension with the predicted cosmological coupling of black.holes with k.3 at a confidence level of~2σ,which challenges the hypothesis that BHs serve as the origin of dark.*** work.on high-redshift AGNs using the JWST will further assess such a hypothesis by identifying more early-type host galaxies in the higher mass range.

关键词： dark.energy supermassive black.hole active galactic nuclei James Webb Space Telescope

A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics

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Journal of Rock.Mechanics and Geotechnical Engineering 2024年第6期16卷 2172-2183页

作者： Liang Wang Xue z.ang Jingjing Meng Qinghua lei Department of Earth Sciences ETH ZürichZürich8092Switzerland Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolL693BXUK Department of Civil Environmental and Natural Resources EngineeringLuleåUniversity of TechnologyLuleå97187Sweden Department of Earth Sciences Uppsala UniversityUppsala75105Sweden

In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated *** approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM *** mitigate the volumetric lock.ng issue in low-order elements,we employ a node-based strain smoothing *** discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the *** express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)***,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point ***,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM *** experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM *** work.holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics.

关键词： Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)

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 z.ang 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 z.ejiang 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)perovsk.te 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-siz. CsPbI_(3)*** exchange strategy maintained the siz. 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) perovsk.te quantum dots Light-emitting diodes Ligand exchange Proton-prompted in-situ exchange

Research on the MPPT of Photovoltaic Power Generation Based on Improved WOA and P&O under Partial Shading Conditions

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Energy Engineering 2024年第4期121卷 951-971页

作者： Jian z.ong lei z.ang Ling Qin School of Electrical Engineering Nantong UniversityNantong226019China

Partial shading conditions(PSCs)caused by uneven illumination become one of the most common problems in photovoltaic(PV)systems,which can mak. the PV power-voltage(P-V)characteristics curve show *** maximum power point track.ng(MPPT)methods have shortcomings in track.ng to the global maximum power point(GMPP),resulting in a dramatic decrease in output *** order to solve the above problems,intelligent algorithms are used in ***,the existing intelligent algorithms have some disadvantages,such as slow convergence speed and large search ***,an improved whale algorithm(IWOA)combined with the P&O(IWOA-P&O)is proposed for the MPPT of PV power generation in this ***,IWOA is used to track.the range interval of the GMPP,and then P&O is used to accurately find the MPP in that *** with other algorithms,simulation results show that this method has an average track.ng efficiency of 99.79%and an average track.ng time of 0.16 s when track.ng ***,experimental verification is conducted,and the results show that the proposed algorithm has better MPPT performance compared to popular particle swarm optimiz.tion(PSO)and PSO-P&O algorithms.

关键词： Photovoltaic power generation maximum power point track.ng whale algorithm perturbation and observation

RepBoTNet-CESA:An Alz.eimer’s Disease Computer Aided Diagnosis Method Using Structural Reparameteriz.tion BoTNet and Cubic Embedding Self Attention

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Computers, Materials & Continua 2024年第5期79卷 2879-2905页

作者： Xiabin z.ang z.ongyi Hu lei Xiao Hui Huang College of Computer Science and Artificial Intelligence Wenzhou UniversityWenzhou325035China k.y Laboratory of Intelligence Image Processing and Analysis Wenzhou UniversityWenzhou325035China

Various deep learning models have been proposed for the accurate assisted diagnosis of early-stage Alz.eimer’s disease(AD).Most studies predominantly employ Convolutional Neural Network.(CNNs),which focus solely on local features,thus encountering difficulties in handling global *** contrast to natural images,Structural Magnetic Resonance Imaging(sMRI)images exhibit a higher number of channel ***,during the Position Embedding stage ofMulti Head Self Attention(MHSA),the coded information related to the channel dimension is *** tack.e these issues,we propose theRepBoTNet-CESA network.an advanced AD-aided diagnostic model that is capable of learning local and global features *** combines the advantages of CNN network. in capturing local information and Transformer network. in integrating global information,reducing computational costs while achieving excellent classification ***,it uses the Cubic Embedding Self Attention(CESA)proposed in this paper to incorporate the channel code information,enhancing the classification performance within the Transformer ***,the RepBoTNet-CESA performs well in various AD-aided diagnosis task.,with an accuracy of 96.58%,precision of 97.26%,and recall of 96.23%in the AD/NC task.an accuracy of 92.75%,precision of 92.84%,and recall of 93.18%in the EMCI/NC task.and an accuracy of 80.97%,precision of 83.86%,and recall of 80.91%in the AD/EMCI/LMCI/NC *** demonstrates that RepBoTNet-CESA delivers outstanding outcomes in various AD-aided diagnostic ***,our study has shown that MHSA exhibits superior performance compared to conventional attention mechanisms in enhancing ResNet ***,the Deeper RepBoTNet-CESA network.fails to mak. further progress in AD-aided diagnostic task..

关键词： Alz.eimer CNN structural reparameteriz.tion multi head self attention computer aided diagnosis

Rapidly growing primordial black.holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 143-150页

作者： Guan-Wen Yuan lei lei Yuan-z.u Wang Bo Wang Yi-Ying Wang Chao Chen z.ao-Qiang Shen Yi-Fu Cai Yi-z.ong Fan k.y Laboratory of Dark.Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China Institute of High Energy Physics Chinese Academy of Sciences Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of China Jock.y Club Institute for Advanced Study The Hong Kong University of Science and Technology

A group of massive galaxies at redshifts of z.7 have been recently detected by the James Webb Space Telescope（JWST）, which were unexpected to form at such an early time within the standard Big Bang cosmology. In this work. we propose that this puz.le can be explained by the presence of some primordial black.holes（PBHs） with a mass of ～1000M⊙. These PBHs act as seeds for early galaxy formation with masses of ～10～8-1010M⊙at high redshift, hence accounting for the JWST observations. We use a hierarchical Bayesian inference framework.to constrain the PBH mass distribution models, and find that the Lognormal model with the Mc～750M⊙is preferred over other hypotheses. These rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects, similar to those recently discovered by JWST. Although we focused on PBHs in this work. the bound on the initial mass of the seed black.holes remains robust even if they were formed through astrophysical channels.

关键词： primordial black.hole dark.matter halo black.hole accretion primordial galaxies

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A performance-based hybrid deep learning model for predicting TBM advance rate using Attention-ResNet-LSTM

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Journal of Rock.Mechanics and Geotechnical Engineering 2024年第1期16卷 65-80页

作者： Sihao Yu z.xin z.ang Shuaifeng Wang Xin Huang Qinghua lei Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghaiChina k.y Laboratory of Geotechnical and Underground Engineering Ministry of EducationTongji UniversityShanghaiChina Department of Earth Sciences ETH ZürichZürichSwitzerland Department of Earth Sciences Uppsala UniversityUppsalaSweden

The technology of tunnel boring machine(TBM)has been widely applied for underground construction worldwide;however,how to ensure the TBM tunneling process safe and efficient remains a major *** rate is a k.y parameter of TBM operation and reflects the TBM-ground interaction,for which a reliable prediction helps optimiz. the TBM ***,we develop a hybrid neural network.model,called Attention-ResNet-LSTM,for accurate prediction of the TBM advance rate.A database including geological properties and TBM operational parameters from the Yangtz. River Natural Gas Pipeline Project is used to train and test this deep learning *** evolutionary polynomial regression method is adopted to aid the selection of input *** results of numerical exper-iments show that our Attention-ResNet-LSTM model outperforms other commonly-used intelligent models with a lower root mean square error and a lower mean absolute percentage ***,parametric analyses are conducted to explore the effects of the sequence length of historical data and the model architecture on the prediction accuracy.A correlation analysis between the input and output parameters is also implemented to provide guidance for adjusting relevant TBM operational *** performance of our hybrid intelligent model is demonstrated in a case study of TBM tunneling through a complex ground with variable ***,data collected from the Baimang River Tunnel Project in Shenz.en of China are used to further test the generaliz.tion of our *** results indicate that,compared to the conventional ResNet-LSTM model,our model has a better predictive capability for scenarios with unk.own datasets due to its self-adaptive characteristic.

关键词： Tunnel boring machine(TBM) Advance rate Deep learning Attention-ResNet-LSTM Evolutionary polynomial regression