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Climate Change of 4℃ Global Warming above Pre-industrial Levels 被引量:6
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作者 Xiaoxin WANG Dabang JIANG Xianmei LANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第7期757-770,共14页
Using a set of numerical experiments from 39 CMIP5 climate models, we project the emergence time for 4?C global warming with respect to pre-industrial levels and associated climate changes under the RCP8.5 greenhouse... Using a set of numerical experiments from 39 CMIP5 climate models, we project the emergence time for 4?C global warming with respect to pre-industrial levels and associated climate changes under the RCP8.5 greenhouse gas concentration scenario. Results show that, according to the 39 models, the median year in which 4?C global warming will occur is 2084.Based on the median results of models that project a 4?C global warming by 2100, land areas will generally exhibit stronger warming than the oceans annually and seasonally, and the strongest enhancement occurs in the Arctic, with the exception of the summer season. Change signals for temperature go outside its natural internal variabilities globally, and the signal-tonoise ratio averages 9.6 for the annual mean and ranges from 6.3 to 7.2 for the seasonal mean over the globe, with the greatest values appearing at low latitudes because of low noise. Decreased precipitation generally occurs in the subtropics, whilst increased precipitation mainly appears at high latitudes. The precipitation changes in most of the high latitudes are greater than the background variability, and the global mean signal-to-noise ratio is 0.5 and ranges from 0.2 to 0.4 for the annual and seasonal means, respectively. Attention should be paid to limiting global warming to 1.5?C, in which case temperature and precipitation will experience a far more moderate change than the natural internal variability. Large inter-model disagreement appears at high latitudes for temperature changes and at mid and low latitudes for precipitation changes. Overall, the intermodel consistency is better for temperature than for precipitation. 展开更多
关键词 4℃ global warming timing climate change signal-to-noise ratio uncertainty
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TIME GLOBAL MILD SOLUTIONS OF NAVIER-STOKES-OSEEN EQUATIONS
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作者 Viet Duoc TRINH 《Acta Mathematica Scientia》 SCIE CSCD 2021年第2期450-460,共11页
In this paper we prove the existence and uniqueness of time global mild solutions to the Navier-Stokes-Oseen equations,which describes dynamics of incompressible viscous fluid flows passing a translating and rotating ... In this paper we prove the existence and uniqueness of time global mild solutions to the Navier-Stokes-Oseen equations,which describes dynamics of incompressible viscous fluid flows passing a translating and rotating obstacle,in the solenoidal Lorentz space L_(σ,w)^(3)·Besides,boundedness and polynomial stability of these solutions are also shown. 展开更多
关键词 Time global mild solutions Navier-Stokes-Oseen equations Oseen operator rotating and translating obstacle
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Key Dolerite Dyke Swarms of Amazonia:U-Pb Constraints on Supercontinent Cycles and Geodynamic Connections with Global LIP Events Through Time
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作者 Wilson TEIXEIRA Mike A.HAMILTON +1 位作者 Vicente A.V.GIRARDI Frederico M.FALEIROS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期84-85,共2页
High-resolution U–Pb(ID-TIMS,baddeleyite)ages are presented for mafic dykes from selected swarms in two important Amazonian regions:the Carajás Province in the east,and the Rio Apa block in the southwest–areas
关键词 Pb U-Pb Constraints on Supercontinent Cycles and Geodynamic Connections with global LIP Events Through Time Key Dolerite Dyke Swarms of Amazonia LIP
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Some comments on biological methylation ,global emissions and trade and on residence time in atmosphere of mercury
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作者 Arne Jernelv 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第S1期102-107,共6页
关键词 Some comments on biological methylation global emissions and trade and on residence time in atmosphere of mercury
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The design of HEPS global timing system 被引量:1
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作者 Fang Liu Ge Lei +11 位作者 Zhe Duan Cai Meng Chenyan Lu Yanhua Shao Xinpeng Ma Nan Gan Yuemei Peng Jianshe Cao Chungming Chu Yanfeng Sui Jingyi Li IHEP 《Radiation Detection Technology and Methods》 CSCD 2021年第3期379-388,共10页
Purpose The high energy photon source(HEPS)is a 4th generation synchrotron light source under construction by the institute of high energy physics.The accelerator complex consists of a 500-MeV Linac,a full-energy sync... Purpose The high energy photon source(HEPS)is a 4th generation synchrotron light source under construction by the institute of high energy physics.The accelerator complex consists of a 500-MeV Linac,a full-energy synchrotron booster,a 6-GeV synchrotron storage ring(SR),and three e-beam transport lines for injection and extraction among accelerators.A global timing system(GTS)covers the timing needs for all accelerator,beamline,and experiment systems.The GTS is designed to coordinate the injection processes and various measurements and protections.Most systems require that the RMS jitter of the GTS signal is less than 30 ps,while the trigger jitters for the electron gun and SR injection and extraction kickers are less than 10 ps.Method The HEPS GTS is an event-based timing system based on MicroTCA.4 hardware architecture.The MicroTCA.4300 series products from the micro-research Finland Oy are implemented in the HEPS GTS system.Results and conclusions The RMS jitter,integrated from 1 Hz to 10 MHz,of the 166.6 MHz event clock is 5.489 ps.The RMS jitter of TTL outputs is less than 30 ps.This paper reports the design of the HEPS GTS,which satisfies all of the HEPS physics requirements for timing with preliminary test results shown. 展开更多
关键词 HEPS global timing system Event timing system MacroTCA.4
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Influence of Node Dynamics on Cluster Global Time Continuity
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作者 李立 刘勇攀 +1 位作者 杨华中 汪蕙 《Tsinghua Science and Technology》 SCIE EI CAS 2011年第2期207-215,共9页
The cluster global time can change in wireless sensor networks due to leader re-elections and node disabilities between two successive synchronizations, which will affect temporal relationships. This paper analyzes cl... The cluster global time can change in wireless sensor networks due to leader re-elections and node disabilities between two successive synchronizations, which will affect temporal relationships. This paper analyzes cluster global time continuity, using global time change models for the node dynamics. The results prove that defining the global time using the cluster average time (AGT) is more stable than defining it using a single node's local time (SGT). With normally distributed clock-parameter assumptions, the AGT change bounds are at most 70.7% of those for the SGT's. The impacts of the initial phase and frequency skew distributions on the global time continuity are also investigated to show that the initial phase variations may strongly influence the continuity. Simulations show that the AGT is more stable with less disabled nodes or larger clusters. The appropriate cluster size is 20-40 when there are less than 15 disabled nodes. 展开更多
关键词 continuous global time AVERAGE wireless sensor networks
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Global stability of a SEIR epidemic model with infectious force in latent period and infected period under discontinuous treatment strategy
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作者 Yanjun Zhao Huilai Li +1 位作者 Wenxuan Li Yang Wang 《International Journal of Biomathematics》 SCIE 2021年第5期221-238,共18页
We consider a SEIR epidemic model with infectious force in latent period and infected period under discontinuous treatment.The treatment rate has at most a finite number of jump discontinuities in every compact interv... We consider a SEIR epidemic model with infectious force in latent period and infected period under discontinuous treatment.The treatment rate has at most a finite number of jump discontinuities in every compact interval.By using Lyapunov theory for discontinuous differential equations and other techniques on non-smooth analysis,the basic reproductive number Ro is proved to be a sharp threshold value which completely determines the dynamics of the model.If Ro<1,then there exists a disease-free equilibrium which is globally stable.If Ro>1,the disease-free equilibrium becomes unstable and there exists an endemic equilibrium which is globally stable.We discuss that the disease will die out in a finite time which is impossible for the corresponding SEIR model with continuous treatment.Furthermore,the numerical simulations indicate that strengthening treatment measure after infective individuals reach some level is beneficial to disease control. 展开更多
关键词 Latent period infected period discontinuous treatment globally stable global convergence in finite time
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Effect of the span of Australian GPS coordinate time series in establishing an optimal noise model 被引量:10
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作者 JIANG WeiPing ZHOU XiaoHui 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第4期523-539,共17页
The span of coordinate time series affects the determination of an optimal noise model. We analyzed position data recorded for 10 continuous Global Positioning System (GPS) sites from 1998.0 to mid-2009 on the Austr... The span of coordinate time series affects the determination of an optimal noise model. We analyzed position data recorded for 10 continuous Global Positioning System (GPS) sites from 1998.0 to mid-2009 on the Australian Plate to estimate the best noise model and thereafter obtain the true uncertainties of the velocity, employing the maximum likelihood estimation (MLE) method. MLE was employed to analyze the data in four ways. In the first two analyses, the noise was assumed to be a combination of flicker noise and white noise for the raw time series and spatially filtered time series. In the final two analyses, the spectral indices and amplitudes were simultaneously estimated for a power law noise plus white noise model for the raw time series and spatially filtered time series. We conclude that the noise model of GPS time series in Australia can be best described as the combination of flicker noise and white noise. Velocity uncertainties fall below -0.2 mm/yr when the time span exceeds -9.5 years. A comparison of noise amplitudes and maximum likelihood estimation values between the raw and spatially filtered time series suggests that traditional spatial filtering to remove common-mode errors might not be applicable to the raw time series of this region. 展开更多
关键词 Australian Plate global Positioning System time series noise model maximum likelihood estimation
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Semi-Linear Fractionalσ-Evolution Equations with Nonlinear Memory
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作者 KAINANE MEZADEK Abdelatif 《Journal of Partial Differential Equations》 CSCD 2020年第4期291-312,共22页
In this paper we study the local or global(in time)existence of small data solutions to semi-linear fractionalσ-evolution equations with nonlinear memory.Our main goals is to explain on the one hand the influence of ... In this paper we study the local or global(in time)existence of small data solutions to semi-linear fractionalσ-evolution equations with nonlinear memory.Our main goals is to explain on the one hand the influence of the memory term and on the other hand the influence of higher regularity of the data on qualitative properties of solutions. 展开更多
关键词 Fractional equations σ-evolution equations global in time existence small data solutions nonlinear memory
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SCALE-TYPE STABILITY FOR NEURAL NETWORKS WITH UNBOUNDED TIME-VARYING DELAYS
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作者 Liangbo Chen Zhenkun Huang 《Annals of Applied Mathematics》 2016年第3期234-248,共15页
This paper studies scale-type stability for neural networks with unbounded time-varying delays and Lipschitz continuous activation functions. Several sufficient conditions for the global exponential stability and glob... This paper studies scale-type stability for neural networks with unbounded time-varying delays and Lipschitz continuous activation functions. Several sufficient conditions for the global exponential stability and global asymptotic stability of such neural networks on time scales are derived. The new results can extend the existing relevant stability results in the previous literatures to cover some general neural networks. 展开更多
关键词 global asymptotic stability global exponential stability neural networks on time scales
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