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Global Freshwater Storage Capability across Time Scales in the GRACE Satellite Era

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Advances in Atmospheric Sciences 2021年第6期38卷 905-917页

作者： Enda ZHU xing yuan Key Laboratory of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China School of Hydrology and Water Resources Nanjing University of Information Science and TechnologyNanjing 210044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Freshwater is recharged mainly by rainfall and stored inland for a period of time,which is directly affected by its storage *** storage capability of river basins has different spatiotemporal features that are important for the predictability of freshwater ***,the estimation of freshwater storage capability(FSC)remains a challenge due to the lack of observations and quantification ***,we use a metric that characterizes hydrological“inertia”after rainfalls to analyze FSC over the 194 largest global major river basins based on satellite observations from the Gravity Recovery and Climate Experiment(GRACE)and simulations from the Community Land Model version 5(CLM5).During 2003–16,the global land was observed to retain 28%of precipitation after one month based on GRACE observations,and the simulation depicts that the retained proportions decrease from 42%after one day to 26%after one month,with smaller FSC partly attributed to wetter conditions and higher vegetation *** root zone contributes about 40%to the global land FSC on daily to monthly time *** the time scale increases,the contribution from the surface soil decreases from 26%to 14%,while the contribution from the deep soil increases from 4%to 10%.Snow contributes over 20%of land FSC,especially over high *** six decades of CLM5 long-term simulations,it is revealed that the change of FSC in most basins is related to internal climate *** FSC of river basins which displays the proportion of precipitation retained on land is worthy of further attention regarding the predictability of water resources.

关键词： freshwater GRACE land surface model soil moisture climate variability storage capability

Underestimation of the Warming Trend over the Tibetan Plateau during 1998–2013 by Global Land Data Assimilation Systems and Atmospheric Reanalyses

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Journal of Meteorological Research 2020年第1期34卷 88-100页

作者： Peng JI xing yuan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049 School of Hydrology and Water Resources Nanjing University of Information Science&TechnologyNanjing 210044

Accurate surface air temperature(T2m)data are key to investigating eco-hydrological responses to global *** of sparse in-situ observations,T2m datasets from atmospheric reanalysis or multi-source observation-based land data assimilation system(LDAS)are widely used in research over alpine regions such as the Tibetan Plateau(TP).It has been found that the warming rate of T2m over the TP accelerates during the global warming slowdown period of 1998–2013,which raises the question of whether the reanalysis or LDAS datasets can capture the warming *** evaluating two global LDASs,five global atmospheric reanalysis datasets,and a high-resolution dynamical downscaling simulation driven by one of the global reanalysis,we demonstrate that the LDASs and reanalysis datasets underestimate the warming trend over the TP by 27%–86%during 1998–*** is mainly caused by the underestimations of the increasing trends of surface downward radiation and nighttime total cloud amount over the southern and northern TP,*** GLDAS2.0,ERA5,and MERRA2 reduce biases of T2m simulation from their previous versions by 12%–94%,they do not show significant improvements in capturing the warming *** WRF dynamical downscaling dataset driven by ERA-Interim shows a great improvement,as it corrects the cooling trend in ERA-Interim to an observation-like warming trend over the southern *** results indicate that more efforts are needed to reasonably simulate the warming features over the TP during the global warming slowdown period,and the WRF dynamical downscaling dataset provides more accurate T2m estimations than its driven global reanalysis dataset ERA-Interim for producing LDAS products over the TP.

关键词： land data assimilation system(LDAS) reanalysis datasets WRF dynamical downscaling Tibetan Plateau global warming slowdown

Two Types of Flash Drought and Their Connections with Seasonal Drought

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Advances in Atmospheric Sciences 2018年第12期35卷 1478-1490页

作者： Linying WANG xing yuan Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences

Flash drought is a rapidly intensifying drought with abnormally high temperature,which has greatly threatened crop yields and water supply,and aroused wide public concern in a warming ***,the preferable hydrometeorological conditions for flash drought and its association with conventional drought at longer time scales remain ***,we investigate two types of flash drought over China:one is high-temperature driven(Type Ⅰ),while the other is water-deficit driven(Type Ⅱ).Results show that the frequencies of the two types of flash drought averaged over China during the growing season are *** I flash drought tends to occur over southern China,where moisture supply is sufficient,while Type Ⅱ is more likely to occur over semi-arid regions such as northern *** types of flash drought increase significantly(p<0.01)during 1979–2010,with a doubled rise in Type Ⅰ as compared with Type Ⅱ.Composite analysis shows that high temperature quickly increases evapotranspiration(ET)and reduces soil moisture from two pentads before the onset of Type Ⅰ flash *** contrast,there are larger soil moisture deficits two pentads before the onset of Type Ⅱ flash drought,leading to a decrease in ET and increase in *** flash drought associated with seasonal drought,there is a greater likelihood of occurrence during the onset and recovery phases of seasonal drought,suggesting perfect conditions for flash drought during transition *** study provides a basis for the early warning of flash drought by connecting multiscale drought phenomena.

关键词： flash drought climate change soil moisture evapotranspiration seasonal drought

Derivation of Tilde Rules in η-ξ Spacetime

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Chinese Physics Letters 1998年第1期15卷 1-2页

作者： ZUO Jian GUI yuan-xing Department of MathematicsDalian University of Technology Dalian 116023 Department of Physics Dalian University of Technology Dalian 116023

The M operation is introduced in η-ξ spacetime to derive the tilde rules in thermo field dynamics (TFD). This leads to an explanation of the tilde system in TFD as the system in region II of η-ξ spacetime.

关键词： spacetime system explanation

Degradation kinetics and products of triazophos in intertidal sediment

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Journal of Environmental Sciences 2005年第6期17卷 933-936页

作者： LIN Kun-de yuan Dong-xing Institute of Environmental Science Zhejiang University Hangzhou 310029 China State Key Laboratory of Marine Environmental Science Environmental Science Research Center Xiamen University Xiamen 361005 China

This work presents taboratory studies on the degradation of triazophos in intertidat sediment. The overall degradations were found to follow the first-order decay model. After being incubated for 6 d, the percentage of degradations of triazophos in unsterilized and sterilized sediments were 94.5% and 20.5%, respectively. Between the temperatures of 15℃ and 35℃, the observed degradation rate constant（kob,d） enhanced as the incubation temperature increased. Triazophos in sediment degraded faster under aerobic condition than under anaerobic one. The water content of sediment had little influence on the degradation when it was in the range of 50%-100%. The values of kobsd decreased with increasing initial concentration of triazophos in sediment, which could result from the microorganism inhibition by triazophos. Four major degradation products, o, o-diethyl phosphorothioic acid, monoethyl phosphorothioic acid, phosphorothioic acid, and 1-phenyl-3-hydroxy-1, 2,4-triazole, were tentatively identified as their corresponding trimethylsilyl derivatives with a gas chromatography-mass spectrometer. The possible degradation pathway of triazophos in intertidal sediment was proposed. The results revealed that triazophos in intertidal sediment was relatively unstable and coutd be easily degraded.

关键词： triazophos degradation intertidal sediment

Derivation of 2×2 Thermal Propagator Without Factorization

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Chinese Physics Letters 1998年第3期15卷 157-158页

作者： ZUO Jian GUI yuan-xing Department of Mathematics Dalian University of TechnologyDalian 116023 Department of Physics Dalian University of TechnologyDalian 116023

The real time thermal propagator with 2×2 matrix structure is derived in the functional formalism of the field theory inη-ξ*** is emphasized that the trouble-shooting factorization of generating functional in the t... 详细信息

关键词： generating derivation functional

Fuzzy neural network based on a Sigmoid chaotic neuron

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Chinese Physics B 2012年第2期21卷 175-180页

作者： Zhang Yi Wang xing-yuan School of Electronic&Information Engineering Dalian University of TechnologyDalian 116024China

The theories of intelligent information processing are urgently needed for the rapid development of modem science. In this paper, a novel fuzzy chaotic neural network, which is the combination of fuzzy logic system, artificial neural network system, and chaotic system, is proposed. We design its model structure which is based on the Sigmoid map, derive its mathematical model, and analyse its chaotic characteristics. Finally the relationship between the accuracy of map and the membership function is illustrated by simulation.

关键词： chaos fuzzy neural network

Thrombolysis and extracorporeal cardiopulmonary resuscitation for cardiac arrest due to pulmonary embolism:A case report

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World Journal of Critical Care Medicine 2025年第1期14卷 111-117页

作者： Guan-xing yuan Zhi-Ping Zhang Jia Zhou Department of Emergency Wuhan Asia General HospitalWuhan 430056Hubei ProvinceChina Department of Neurosurgery Central Theater Command General HospitalWuhan 430000Hubei ProvinceChina

BACKGROUND Cardiac arrest caused by acute pulmonary embolism(PE)is the most serious clinical circumstance,necessitating rapid identification,immediate cardiopulmonary resuscitation(CPR),and systemic thrombolytic *** CPR(ECPR)is typically employed as a rescue therapy for selected patients when conventional CPR is failing in settings where it can be *** SUMMARY We present a case of a 69-year-old male who experienced a prolonged cardiac arrest in an ambulance with pulseless electrical *** arrival at the emergency department with ongoing manual chest compressions,bedside pointof-care ultrasound revealed an enlarged right ventricle without *** PE was suspected as the cause of cardiac arrest,and intravenous thrombolytic therapy with 50 mg tissue plasminogen activator was administered during mechanical chest *** 31 minutes of CPR,return of spontaneous circulation was not achieved until 8 minutes after initiation of Veno-arterial extracorporeal membrane oxygenation(ECMO)*** ECMO support,the hemodynamic status and myocardial contractility significantly ***,the patient ultimately did not survive due to intracerebral hemorrhagic complications,leading to death a few days later in the *** This case illustrates the potential of combining systemic thrombolysis with ECPR for refractory cardiac arrest caused by acute PE,but it also highlights the increased risk of significant bleeding complications,including fatal intracranial hemorrhage.

关键词： Pulmonary embolism Cardiac arrest Thrombolytic therapy Cardiopulmonary resuscitation Extracorporeal membrane oxygenation Intracranial hemorrhage Case report

Feedrate scheduling method for constant peak cutting force in five-axis flank milling process

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Chinese Journal of Aeronautics 2020年第7期33卷 2055-2069页

作者： Liping WANG xing yuan Hao SI Feiyu DUAN School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

It is extremely important to select appropriate feedrates for the stable machining of parts with ruled surface in modern aviation industrial ***,the current studies take too much time to achieve this ***,this paper presents an efficient feedrate optimization method for constant peak cutting force in five-axis flank milling *** solution method of the instantaneous undeformed chip thickness(IUCT)is proposed using least squares theory with the cutter entry angle and feedrate as *** on this method,an explicit analytical expression of the peak cutting force for each cutting point is ***,a feedrate scheduling method is developed to quickly solve the appropriate feedrate under constant peak cutting *** verify the proposed IUCT model,the fitting IUCT is compared with the accuracy data at different ***,some experiments of five-axis flank milling are conducted to demonstrate the effectiveness of the peak force model and the feedrate scheduling *** the surface roughness before and after feedrate scheduling is *** results show that the proposed feedrate scheduling method can quickly adjust the feedrate and ensure constant peak force during *** the same time,the surface quality is kept at a high level.

关键词： Cutter runout Feedrate scheduling Force control Instantaneous undeformed chip thickness Peak cutting force