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The Microphysical Characteristics of Wintertime Cold Clouds in North China

Advances in Atmospheric Sciences 2022年第12期39卷 2056-2070页

作者： Xuexu WU Minghuai WANG Delong ZHAO Daniel ROSENFELD Yannian ZHU Yuanmou DU Wei ZHOU Ping TIAN jiujiang sheng Fei WANG Deping DING School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Joint International Research Laboratory of Atmospheric and Earth System Sciences&Institute for Climate and Global Change Research Nanjing UniversityNanjing 210023China Beijing Weather Modification Office Beijing 100089China Institute of Earth Sciences The Hebrew University of JerusalemJerusalem 91904Israel

The microphysical characteristics of wintertime cold clouds in North China were investigated from 22 aircraft observation flights from 2014 to 2017,2020,and *** clouds were generated by mesoscale weather systems with little orographic *** the mixed-phase temperature range(–40℃to 0℃),the average fraction of liquid,mixedphase,and ice cloud was 4.9%,23.3%,and 71.8%,respectively,and the probability distribution of ice mass fraction was a half-U-shape,suggesting that ice cloud was the primary cloud *** wintertime mixed-phase clouds in North China were characterized by large cloud droplet number concentration,small liquid water content(LWC),and small effective diameter of cloud *** main reason for larger cloud droplet number concentration and smaller effective diameter of cloud droplets was the heavy pollution in winter in North China,while for smaller LWC was the lower temperature during flights and the difference in air mass *** the temperature increasing,cloud droplet number concentration,LWC,and the size of ice particles increased,but ice number concentration and effective diameter of cloud droplets decreased,similar to other mid-latitude regions,indicating the similarity in the temperature dependence of cloud properties of mixed-phase *** variation of the cloud properties and ice habit at different temperatures indicated the operation of the aggregation and riming processes,which were commonly present in the wintertime mixed-phase *** study fills a gap in the aircraft observation of wintertime cold clouds in North China.

关键词： cold clouds aircraft observation microphysical character North China

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Epidemiology and current management of cerebrovascular disease in China

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Journal of Geriatric Cardiology 2024年第5期21卷 465-474页

作者： sheng-Shou HU The Writing Committee of the Report on Cardiovascular Health and Diseases in China

The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in *** connection with the previous section,this fifth section of the report continues the dissection on the manage-ment of cardiovascular diseases(CVD).Cerebrovascular disease is the leading cause of death and loss of healthy life among Chinese *** on the results of GBD 2019,from 1990 to 2019,the years of life lost due to premature death caused by stroke showed a decreasing trend,while the years lived with disability still increased *** present,national mortal-ity surveillance system can provide national and provincial representative annual death data on cerebrovascular disease,but the national representative data on some other important epidemiological indicators(such as incidence,prevalence,disability rate,and case fatality rate)are scarce in *** the construction of large cohort population and extension of follow-up time,re-search on stroke-related risk factors is increasing,providing a basis for the prevention and control of risk *** to limited large-scale population-based intervention studies,there is a lack of epidemiological evidence to transform into feasible interven-tion strategies and *** recent years,great progress in endovascular treatment for basilar-artery occlusion has been achieved in China,but there is still much room for improvement of guideline-based anticoagulant treatment and lipid-lowering treatment,as well as standardized diagnosis and treatment among patients with ischemic stroke.

关键词： prevention diagnosis Epidemiology

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Epidemiology and current management of cardiovascular disease in China

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Journal of Geriatric Cardiology 2024年第4期21卷 387-406页

作者： sheng-Shou HU the Writing Committee of the Report on Cardiovascular Health and Dis-eases in China Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

The Annual Report on Cardiovascular Health and Diseases in China(2022) intricate landscape of cardiovascular health in China. This is the fourth section of the report with a specific focus on epidemiology and current management of cardiovascular disease(CVD) in China. This section of the report highlights the epidemiological trends of CVD in China. It reveal a concerning rise in prevalence, with approximately 330 million affected individuals, including significant numbers with stroke, coronary artery disease(CAD), heart failure, and other conditions. CVD stands as the primary cause of mortality among both urban and rural populations, accounting for nearly half of all deaths in 2020. Mortality rates are notably higher in rural areas compared to urban centers since 2009. While age-standardized mortality rates have decreased, the absolute number of CVD deaths has increased, primarily due to population aging. Ischemic heart disease, hemorrhagic and ischemic strokes are the leading causes of CVD-related deaths. Notably, the burden of atherosclerotic cardiovascular disease has risen substantially, with atherosclerotic cardiovascular disease-related deaths increasing from 1990 to 2016. The incidence of ischemic stroke and ischemic heart disease has shown similar increasing trends over the past three decades. CAD mortality, particularly acute myocardial infarction, has been on the rise, with higher mortality rates observed in rural areas since 2016. The prevalence of CAD has increased significantly, with over 11 million patients identified in 2013. Studies assessing hospital performance in managing acute coronary syndrome reveal gaps in adherence to guideline-recommended strategies, with disparities in care quality across hospitals. However, initiatives like the China Patient-centered Evaluative Assessment of Cardiac Events(PEACE)-Retrospective AMI Study and the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome(CCC-ACS) project aim to improve patien

关键词： epidemiology landscape deaths

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In silico optimization of actuation performance in dielectric elastomercomposites via integrated finite element modeling and deep learning

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 48-56页

作者： Jiaxuan Ma sheng Sun Materials Genome Institute Shanghai UniversityShanghai 200444China Zhejiang Laboratory Hangzhou 311100China Shanghai Frontier Science Center of Mechanoinformatics Shanghai UniversityShanghai 200444China

Dielectric elastomers(DEs)require balanced electric actuation performance and mechanical integrity under applied *** high dielectric particles as fillers provides extensive design space to optimize concentration,morphology,and distribution for improved actuation performance and material *** study presents an integrated framework combining finite element modeling(FEM)and deep learning to optimize the microstructure of DE *** first calculates actuation performance and the effective modulus across varied filler combinations,with these data used to train a convolutional neural network(CNN).Integrating the CNN into a multi-objective genetic algorithm generates designs with enhanced actuation performance and material modulus compared to the conventional optimization approach based on FEM approach within the same *** framework harnesses artificial intelligence to navigate vast design possibilities,enabling optimized microstructures for high-performance DE composites.

关键词： Dielectric elastomer composites Multi-objective optimization Finite element modeling Convolutional neural network

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Centered Waves for the Two-dimensional Pseudo-Steady van der Waals Gas Satisfied Maxwell's Law Around a Sharp Corner

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Chinese Annals of Mathematics,Series B 2024年第4期45卷 537-554页

作者： Shuangrong LI Wancheng sheng Department of Mathematics Shanghai University Shanghai 200444 China Department of Mathematics Zhejiang University of Science and Technology Department of Mathematics Newtouch Center for Mathematics of Shanghai University Shanghai University

In this paper, the authors study the centered waves for the two-dimensional(2D for short) pseudo-steady supersonic flow with van der Waals gas satisfied Maxwell's law around a sharp corner. In view of the initial value of the specific volume and the properties of van der Waals gas, the centered waves at the sharp corner are constructed by classification. It is shown that the supersonic incoming flow turns the sharp corner by a centered simple wave or a centered simple wave with right-contact discontinuity or a composite wave(jump-fan, fan-jump or fan-jump-fan), or a combination of waves and constant state. Moreover, the critical angle of the sharp corner corresponding to the appearance of the vacuum phenomenon is obtained.

关键词： Centered simple wave Composite wave Two-dimensional Euler equations Van der Waals gas

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Constraints on real scalar inflation from preheating using LATTICEEASY

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Chinese Physics C 2024年第6期48卷 240-246页

作者：程伟秦通姜玖江周瑞雨 School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China

In this paper,we undertake a detailed study of real scalar inflation using LATTICEEASY simulations to investigate preheating ***,the scalar inflation potential with non-minimal coupling can be approximated using a quartic *** observe that the evolutionary behavior of this potential remains unaffected by the coupling ***,the theoretical predictions for the scalar spectral index(n_(s))and tensor-toscalar power ratio(r)are independent of this ***,the coefficients of this model are not constrained by Planck ***,the properties of preheating after inflation provide a viable approach to examining these *** LATTICEEASY simulations,we trace the evolution of particle number density,scale factor,and energy density during the preheating ***,we derive the parameters,such as the energy ratio(γ)and the e-folding number of preheating(N_(pre)),which facilitate further predictions of n s and *** successfully validate real scalar inflation model using preheating in LATTICEEASY simulations based on the analytical relationship between preheating and inflation models.

关键词： inflation latticeeasy preheating

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Influencing Factors on Cardiovascular Health in China

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Journal of Geriatric Cardiology 2024年第1期21卷 4-33页

作者： sheng-Shou HU 无 Fuwai Hospital Chinese Academy of Medical Sciences BeijingChina the Writing Committee of the Report on Cardiovascular Health and Diseases in China

The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in *** is the first section of the report,which dissects influential factors across diverse *** investigation identifies tobacco use as a paramount concern,portraying China as the global epicenter of tobacco *** smoking,exacerbated by second-hand smoke exposure,emerges as a critical and preventable risk factor,contributing to a surge in attributable deaths over the past three *** the realm of dietary nutrition,the study discerns an overall improvement,yet discerns worrisome deviations,notably an escalating fat intake surpassing recommended *** shifting dietary structure reveals diminished consumption of cereals and vegetables juxtaposed with an uptick in animal foods,while excessive intake of cooking oil and salt persists,straying substantially from endorsed *** exploration of physical activity patterns unfolds a nuanced *** trends are observed among students,with concerns arising from sedentary behaviors and inadequate adherence to recommended *** analysis spans a trajectory of declining physical activity in Chinese adults,coupled with an alarming surge in sedentary leisure time,ultimately linking these factors to heightened risks of cardiovascular diseases and increased *** examination of overweight and obesity trends uncovers a relentless upward trajectory,projecting substantial prevalence by *** prevalence rates underscore the imperative for targeted interventions to curtail this burgeoning health crisis,with the anticipated prevalence extending to nearly two-thirds of the adult *** factors,notably depression,constitute an integral facet of cardiovascular *** rates among patients with coronary artery disease and acute myocardial infarction underscore the intricate interplay between mental health and cardiovascular

关键词： Influencing smoke linking

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Incorporating contextual evidence to improve implicit discourse relation recognition in Chinese

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Frontiers of Computer Science 2024年第3期18卷 91-104页

作者： sheng XU Peifeng LI Qiaoming ZHU School of Computer Science and Technology Soochow UniversitySuzhou 215000China

The discourse analysis task,which focuses on understanding the semantics of long text spans,has received increasing attention in recent *** a critical component of discourse analysis,discourse relation recognition aims to identify the rhetorical relations between adjacent discourse units(e.g.,clauses,sentences,and sentence groups),called arguments,in a *** works focused on capturing the semantic interactions between arguments to recognize their discourse relations,ignoring important textual information in the surrounding ***,in many cases,more than capturing semantic interactions from the texts of the two arguments are needed to identify their rhetorical relations,requiring mining more contextual *** this paper,we propose a method to convert the RST-style discourse trees in the training set into dependency-based trees and train a contextual evidence selector on these transformed *** this way,the selector can learn the ability to automatically pick critical textual information from the context(i.e.,as evidence)for arguments to assist in discriminating their *** we encode the arguments concatenated with corresponding evidence to obtain the enhanced argument ***,we combine original and enhanced argument representations to recognize their *** addition,we introduce auxiliary tasks to guide the training of the evidence selector to strengthen its selection *** experimental results on the Chinese CDTB dataset show that our method outperforms several state-of-the-art baselines in both micro and macro F1 scores.

关键词： discourse parsing discourse relation recognition contextual evidence selection

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Influence of the Acoustic Liner in Large Eddy Simulation of Longitudinal Thermoacoustic Instability in a Model Annular Combustor

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Journal of Thermal Science 2024年第2期33卷 710-724页

作者： MENG sheng ZHANG Man GAO Yi AECC Commercial Aircraft Engine Co. Ltd.Shanghai200241China School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China

Although extensive efforts have been made to dampen the thermoacoustic instability,successfully controlling the pressure oscillations in modern gas turbines or aeroengines remains *** influence of the acoustic liner on the longitudinal thermoacoustic mode in a model annular combustor is investigated by Large Eddy Simulation(LES) in this *** result of the self-excited longitudinal thermoacoustic instability without the liner agrees well with the frequency and acoustic analysis of the pressure mode based on experimental *** different bias flow velocities of the liner located downstream of the combustor are then *** results reveal that the existence of the liner influences not only the acoustic field but also the flow *** the bias velocity is large,it leads to intense turbulence-induced fluctuations,and the pressure oscillation is modulated *** shows that the weak coupling between flow and pressure oscillations plays a significant role in the onset of the intermittency of a thermoacoustic *** on the dynamic analysis of the thermoacoustic system with the acoustic liner,this intermittency is caused by the influence of the flow field on the flame-acoustic ***,a low-order modeling method based on Van der Pol(VdP) oscillator with additive stochastic forcing is conducted to reproduce the evolving dynamics of the thermoacoustic *** the numerical cases demonstrated in this work are relatively simpler than those in a practical combustion system,the results are helpful for us to understand the effect of the acoustic liner and show the attractive potential to apply this device to suppress thermoacoustic instability.

关键词： thermoacoustic instability acoustic liner Large Eddy Simulation low-order modeling

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Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1661-1667页

作者： Gu-jun Chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

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