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Global Stability of Traveling Wavefronts for a Belousov-Zhabotinsky Model with Mixed Nonlocal and Degenerate Diffusions
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作者 Yuting YANG Guobao ZHANG 《Journal of Mathematical Research with Applications》 2026年第1期87-102,共16页
In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocal... In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocally diffusive species and degenerately diffusive species.We prove that the traveling wavefronts are exponentially stable,when the initial perturbation around the traveling waves decays exponentially as x→-∞,but in other locations,the initial data can be arbitrarily large.The adopted methods are the weighted energy with the comparison principle and squeezing technique. 展开更多
关键词 Belousov-Zhabotinsky model nonlocal diffusion stability comparison principle weighted energy
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Long-Term Governance and Global Stability
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作者 AUGUSTO SOTO 《China Today》 2025年第10期34-36,共3页
Through its unique five-year planning system,China demonstrates how long-term,strategic policy continuity can effectively address both domestic and global challenges.
关键词 domestic challenges global challenges policy continuity five year planning system long term governance global stability
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GLOBAL STABILITY OF TRAVELING WAVES FOR SOME MULTIDIMENSIONAL SEMILINEAR HYPERBOLIC SYSTEMS
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作者 Dongbing ZHA Yue ZHAO 《Acta Mathematica Scientia》 2025年第4期1391-1404,共14页
For multidimensional first order semilinear hyperbolic systems of diagonal form without self-interaction,we show the global nonlinear stability of traveling wave solutions.
关键词 semilinear hyperbolic systems traveling wave global stability
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WEAPONIZING TRADE, UNDERMINING TRUST The Trump administration’s politicization of global economics threatens international stability and damages China-U.S. relations
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作者 Hamzah Rifaat Hussain 《China Report ASEAN》 2025年第5期64-64,共1页
If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the... If there were any doubts about the Trump administration’s inherent obsession with decoupling,polarization and jolting of global trade,they can be laid to rest.A series of statements and measures have been made by the U.S.government on economic relations with China including administrative decision to hit Chinese goods with additional tariffs despite China. 展开更多
关键词 global trade economic relations trade decoupling international stability tariffs polarization TRUST china u s relations
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SHAPING STABILITY THROUGH PARTNERSHIP China and ASEAN are navigating global uncertainties by deepening strategic ties
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作者 Ahmad Syaifuddin Zuhri 《China Report ASEAN》 2025年第8期53-55,共3页
The evolution of China-ASEAN relations ranks among the most significant geopolitical and economic dynamics of the 21st Century.Comprising 10 Southeast Asian nations,ASEAN has held the position of China’s largest trad... The evolution of China-ASEAN relations ranks among the most significant geopolitical and economic dynamics of the 21st Century.Comprising 10 Southeast Asian nations,ASEAN has held the position of China’s largest trading partner since 2020.This partnership is underpinned by sustained economic growth,political stability,security cooperation,and vibrant socio-cultural exchanges.Over the past two decades,the China-ASEAN relationship has emerged as a main axis in Asia’s geopolitical and economic landscape.By 2025,this partnership has entered a more intricate and strategic phase marked by deeper economic collaboration,expanded multilateral diplomacy,and mounting challenges stemming from global developments such as tari"wars and South China Sea tensions. 展开更多
关键词 southeast asian China ASEAN relations economic growth political stability geopolitical economic dynamics global uncertainties strategic ties security cooperation
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基于Global Search算法优化近红外测距光学系统
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作者 冯浩 王丽娇 +6 位作者 莫维全 袁必诚 杨志颖 张楠 王开金 刘琨 孙昊 《应用光学》 北大核心 2026年第2期243-252,共10页
为实现户外红外测距系统在有限封闭空间内的精准探测,在不影响探测结果的基础上压缩光学系统体积,采用二维双平面反射系统,设计了一套光学总长为4 m、最大反射镜为12.8 cm的折返式光路。该折返式光路将n片平面反射镜分为2×(n+1)段... 为实现户外红外测距系统在有限封闭空间内的精准探测,在不影响探测结果的基础上压缩光学系统体积,采用二维双平面反射系统,设计了一套光学总长为4 m、最大反射镜为12.8 cm的折返式光路。该折返式光路将n片平面反射镜分为2×(n+1)段光程,利用全局搜索算法(Global Search)对反射镜数量和光学直径进行优化,实现每条探测光线都能照射到探测物体并成功折返回探测器;满足探测要求后,利用信号波原理进行理论验证分析,避免光程折损引起探测误差;最后,通过分析系统在封闭空间内杂散光线的仿真结果,对系统进行杂散光抑制,对实验与原路径的探测结果进行对比,验证了设计光路的正确性和准确性。 展开更多
关键词 光路设计 global Search算法 杂散光 信号波
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Global-local feature optimization based RGB-IR fusion object detection on drone view 被引量:1
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作者 Zhaodong CHEN Hongbing JI Yongquan ZHANG 《Chinese Journal of Aeronautics》 2026年第1期436-453,共18页
Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still st... Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still struggle to deal with the complex and changing scenarios captured by drones,mainly due to two reasons:(A)RGB-IR fusion detectors are susceptible to inferior inputs that degrade performance and stability.(B)RGB-IR fusion detectors are susceptible to redundant features that reduce accuracy and efficiency.In this paper,an innovative RGB-IR fusion detection framework based on global-local feature optimization,named GLFDet,is proposed to improve the detection performance and efficiency of drone-captured objects.The key components of GLFDet include a Global Feature Optimization(GFO)module,a Local Feature Optimization(LFO)module and a Channel Separation Fusion(CSF)module.Specifically,GFO calculates the information content of the input image from the frequency domain and optimizes the features holistically.Then,LFO dynamically selects high-value features and filters out low-value features before fusion,which significantly improves the efficiency of fusion.Finally,CSF fuses the RGB and IR features across the corresponding channels,which avoids the rearrangement of the channel relationships and enhances the model stability.Extensive experimental results show that the proposed method achieves the best performance on three popular RGB-IR datasets Drone Vehicle,VEDAI,and LLVIP.In addition,GLFDet is more lightweight than other comparable models,making it more appealing to edge devices such as drones.The code is available at https://github.com/lao chen330/GLFDet. 展开更多
关键词 Object detection Deep learning RGB-IR fusion DRONES global feature Local feature
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Dynamics of the perturbed Calogero-Moser system:well-posedness,stability and blow up
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作者 LIU Qianle WANG Zhong ZHU Weipeng 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第1期157-168,共12页
We investigate a class of non-integrable two-particle Calogero-Moser systems modulated by a power-law external potential.The local well-posedness of the Cauchy problem is established under the strict initial separatio... We investigate a class of non-integrable two-particle Calogero-Moser systems modulated by a power-law external potential.The local well-posedness of the Cauchy problem is established under the strict initial separation condition for the particles.For suitably prepared initial configurations,local solutions can be extended globally via energy conservation;conversely,negative energy conditions induce(in)finite-time blowup.The linear(in)stability of stationary solutions is analyzed,with their energy serving as a threshold.Numerical investigations employ a fourth-order Runge-Kutta scheme with adaptive step-size control.Simulations demonstrate that the trajectories either converge to steady states or exhibit blowup,depending on the power exponent α and initial conditions.Increasingαaccelerates the convergence rate and dampens oscillatory dynamics,promoting a transition from periodic behavior to static equilibrium. 展开更多
关键词 Calogero-Moser system WELL-POSEDNESS blow up stability
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Stability and Hopf Bifurcation of a Reaction-Diffusion-Advection Model with Nonlocal Delay
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作者 ZHAN Jidan YU Ke PENG Yahong 《应用数学》 北大核心 2026年第2期373-387,共15页
In ecological environments,the survival environment of species is often inhomogeneous,and the reproductive process is affected by time delay.System with nonlocal effects and delay can more accurately simulate changes ... In ecological environments,the survival environment of species is often inhomogeneous,and the reproductive process is affected by time delay.System with nonlocal effects and delay can more accurately simulate changes in population density.In this paper,we consider a reaction-diffusion-advection model with nonlocal delay and Dirichlet boundary conditions.First of all,we investigate the well-posedness of solution of model.Then,the existence of positive steady state is proofed by implicit function theorem.Based on a priori estimate for the eigenvalue,we prove the stability of the positive steady state and conclude the associated distribution of Hopf bifurcation.Our research indicates that the combined effects of nonlocal and time delays have a certain impact on the dynamics of the model. 展开更多
关键词 NONLOCALITY Time delay Reaction-diffusion-advection Hopf bifurcation stability
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Systematic evaluation of reference gene stability across tissues and sexes in cuttlefish(Sepiella japonica)
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作者 LI Shuang GU Min +5 位作者 YE Xiaowen YE Bin LIU Siyu YU Jia ZHOU Xu CHI Changfeng 《水产学报》 北大核心 2026年第2期26-49,共24页
Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa su... Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa such as cephalopods,systematic evaluation of reference genes is limited,leading to potential bias.The cuttlefish Sepiella japonica is ecologically and economically important in China,yet previous molecular studies have often relied on single unvalidated reference genes,which may compromise data reliability.This study aimed to systematically evaluate the stability of five commonly used reference genes(18S,ef-1α,ef-1γ,gapdh,andβ-actin)across multiple tissues and sexes of S.japonica,and to identify the most suitable reference genes and optimal number for qPCR normalization.Fifteen to sixteen tissue types were collected from ten healthy adults(five males and five females).Total RNA was extracted,reverse-transcribed,and analyzed by qPCR.Gene stability was assessed using four algorithms(geNorm,NormFinder,BestKeeper,andΔCt)integrated with RefFinder,and the optimal gene number was determined using geNorm pairwise variation(V_(n/n+1)<0.15).Four transcriptome-derived genes(creld2,cd109,acy1,and miox)were used for validation.The C_(t)values of the five genes ranged from 15.47 to 20.83.β-actin and gapdh showed pronounced variability in expression stability among tissues and sexes,indicating their limited suitability for normalization.18S exhibited the highest expression(mean C_(t):15.47-16.29)and lowest variability but displayed sex-biased expression,whereas ef-1αand ef-1γremained consistently stable across most tissues in both sexes,with ef-1αbeing the most robust and showing no sex-related bias.Although specific rankings varied among tissues and sexes,the comprehensive results indicated that ef-1αand ef-1γpossessed the highest overall stability,followed by 18S,whileβ-actin and gapdh were the least stable.The final comprehensive rankings were ef-1γ>ef-1α>18S>gapdh>β-actin(male)and ef-1α>ef-1γ>18S>gapdh>β-actin(female).geNorm analysis(V2/3<0.15)indicated that two genes,mainly ef-1αand ef-1γ,were generally sufficient for reliable normalization in most tissues.Validation confirmed that normalization using the stable ef-1αand ef-1γaccurately reflected the expression differences among tissues,whereasβ-actin and gapdh can bias or confound statistical analyses.ef-1αand ef-1γare identified as the most reliable reference gene combination for qPCR analysis in S.japonica,while 18S can serve as an auxiliary gene for within-sex comparisons.The use ofβ-actin or gapdh alone is not recommended.This study establishes a systematic framework for selecting reliable reference genes in S.japonica,thereby facilitating robust qPCR normalization and providing a foundation for future gene expression research in S.japonica and other cephalopods. 展开更多
关键词 Sepiella japonica reference genes qPCR expression stability RefFinder
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Effect of Element Ti on Microstructure,Properties,and Thermal Stability of NbTaMoWTi_(x)Refractory High-Entropy Alloys
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作者 Ou Pengcheng Wan Qiang +5 位作者 Jiang Hui Sha Minghong Sun Jiabin Ai Xingang Li Shengli Huang Tiandang 《稀有金属材料与工程》 北大核心 2026年第5期1184-1190,共7页
The effect of element Ti on the microstructures and mechanical properties of as-cast and annealed NbTaMoWTi,(x=0,1,1.5,2)refractory high-entropy alloys(RHEAs)was investigated.Results show that after Ti addition,the as... The effect of element Ti on the microstructures and mechanical properties of as-cast and annealed NbTaMoWTi,(x=0,1,1.5,2)refractory high-entropy alloys(RHEAs)was investigated.Results show that after Ti addition,the as-cast alloys maintain their original single body-centered cubic(bcc)structure.As for the mechanical properties,compared with those without Ti addition,the strength and ductility of NbTaMoWTi,alloys increase by 93%and 215%,respectively.Furthermore,the NbTaMoWTi alloys exhibit outstanding thermal stability.After annealing at 1400 C,they still maintain the single bcc structure,and their mechanical properties are even slightly improved.However,annealing leads to a significant deterioration in the mechanical properties of high-Ti-content alloys(NbTaMoWTil and NbTaMoWTi2),owing to the formation of Ti-rich acicular phases. 展开更多
关键词 high-entropy alloys refractory alloy TITANIUM mechanical properties thermal stability
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The 2024 Global Security Dynamics: Rising Risks of Instability and Growing Demand for Governance
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作者 Tang Yongsheng 《Contemporary World》 2025年第1期19-23,共5页
In 2024, as the world underwent profound political changes, global security faced increasing instabilities and uncertainties. Traditional and non-traditional security threats interacted and overlapped, and the risk of... In 2024, as the world underwent profound political changes, global security faced increasing instabilities and uncertainties. Traditional and non-traditional security threats interacted and overlapped, and the risk of turmoil increased. Strategic trust among major powers continued to erode, leading to heightened insecurity and intensified competition. 展开更多
关键词 global security major powers competition uncertainties strategic trust traditional security threats INSTABILITIES non traditional security threats
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Global Existence and Blow-up of Solutions for Fourth-order Parabolic Equation with p(x)-Laplacian and Variable Exponents
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作者 YANG Chunxiao YU Lifei DUAN Chenyan 《数学进展》 北大核心 2026年第1期221-239,共19页
In this paper,we consider the fourth-order parabolic equation with p(x)Laplacian and variable exponent source ut+∆^(2)u−div(|■u|^(p(x)−2■u))=|u|^(q(x))−1u.By applying potential well method,we obtain global existence... In this paper,we consider the fourth-order parabolic equation with p(x)Laplacian and variable exponent source ut+∆^(2)u−div(|■u|^(p(x)−2■u))=|u|^(q(x))−1u.By applying potential well method,we obtain global existence,asymptotic behavior and blow-up of solutions with initial energy J(u_(0))≤d.Moreover,we estimate the upper bound of the blow-up time for J(u_(0))≤0. 展开更多
关键词 fourth-order parabolic equation variable exponent source global existence asymptotic behavior BLOW-UP
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China's Global Governance Initiative Illuminates the Path toward Good Climate Governance
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作者 Zhao Bin Zhang Yating Wang Nan 《Contemporary International Relations》 2026年第1期20-40,共21页
The Global Governance Initiative(GGI)is another important public good that China has provided for the international community,following the Global Development Initiative,the Global Security Initiative,and the Global C... The Global Governance Initiative(GGI)is another important public good that China has provided for the international community,following the Global Development Initiative,the Global Security Initiative,and the Global Civilization Initiative.As a sub-field of global governance,global climate governance has hitherto progressed slowly,exhibiting growing deficits in discourse,institutions,and actions.The governance paradigm is in desperate need of revamping,especially under the guidance of an innovative initiative.At the conceptual level,the GGI has gone beyond the Western governance discourse by outlining the institutional starting point,foundations of legitimacy,action orientations,ultimate goals,and practical support for good global climate governance through its five core concepts.At the practical level,the spillover effects of China's achievements in climate governance and the collective rise of the Global South have created favorable conditions,domestically and internationally,for the GGI to lead the way forward toward good global climate governance.However,the fact that the international political and economic order remains unjust and inequitable indicates that this will inevitably be a long-term process replete with rivalries in the pursuit of breakthroughs. 展开更多
关键词 global climate governance global climate politics global Governance Initiative good governance
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Influence of SiC Content on Foaming Stability,Cell Structure,and Compression Performance of SiC/Al-Based Composite Foam Prepared by Two-Step Foaming Method
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作者 Huang Wenzhan Liu Tao +3 位作者 Chen Yao Wang Lucai Wu Jianguo You Xiaohong 《稀有金属材料与工程》 北大核心 2026年第4期890-898,共9页
SiC/Al-based composite foams were prepared by a two-step foaming method.The influence of the SiC content and its distribution uniformity on the foaming stability,cell structure,and mechanical properties of the aluminu... SiC/Al-based composite foams were prepared by a two-step foaming method.The influence of the SiC content and its distribution uniformity on the foaming stability,cell structure,and mechanical properties of the aluminum foams was investigated.The macro/micro-features of the aluminum foams were characterized and analyzed.Results demonstrate that an appropriate increase in SiC content and the uniform distribution of SiC can improve the foaming stability,optimize the cell diameter and cell wall thickness,ameliorate the cell distribution,and enhance the hardness and compressive strength of the aluminum foams.However,either insufficient or excessive SiC leads to uneven distribution of SiC particles,which is unfavorable to foaming stability and good cell structure formation.With 6wt%SiC,both the foaming stability and cell structure of the aluminum foam reach the optimal state,resulting in the highest compressive strength and optimal energy absorption capacity. 展开更多
关键词 aluminum foam two-step foaming method foaming stability cell structure HARDNESS compressive strength
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ASYMPTOTIC STABILITY OF GLOBAL SOLUTIONS FOR A CLASS OF SEMILINEAR WAVE EQUATION
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作者 Mutong HE Feimin HUANG Tianyi WANG 《Acta Mathematica Scientia》 2025年第6期2685-2714,共30页
This paper establishes the asymptotic stability of a composite wave for a damped wave equation with partially linearly degenerate flux.The global solution is shown to converge to a combination of a rarefaction wave an... This paper establishes the asymptotic stability of a composite wave for a damped wave equation with partially linearly degenerate flux.The global solution is shown to converge to a combination of a rarefaction wave and a viscous contact wave as time tends to infinity by employing the L^(2) energy method and a refined wave interaction analysis.This is the first result on the asymptotics toward multiwave for the damped wave equation,and this asymptotic stability result does not rely on the small assumption of neither the initial perturbations nor the wave strength. 展开更多
关键词 asymptotic stability rarefaction wave viscous contact wave linearly degenerate flux L^(2)energy method
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Some Thoughts on Promoting Global Governance in the Context of Decentralization
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作者 Jia Qingguo 《Contemporary International Relations》 2026年第1期4-14,共11页
In recent years, the overall strength of Western developed countries, led by the United States, has declined relatively, resulting in a trend of decentralization. This has posed severe challenges to the traditional gl... In recent years, the overall strength of Western developed countries, led by the United States, has declined relatively, resulting in a trend of decentralization. This has posed severe challenges to the traditional global governance system with regard to trade, security, and multilateral cooperation. However, this trend also provides a historical opportunity to transform the global governance system into one that is more inclusive and equitable. This can be seen in the reconstruction of value priorities, the adjustment of governance focus, the reform of governance mechanisms, and the promotion of new mechanisms. Only by adhering to openness and inclusiveness and balancing rights and responsibilities can we build a future governance order that conforms to the common interests of all humanity. 展开更多
关键词 DECENTRALIZATION global governance global Governance Initiative initiative diplomacy
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The Global South’s Opportunity:An Arab Reading of the Global Governance Initiative
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作者 Adham Sayed 《Contemporary World》 2026年第1期23-27,共5页
Multiple diagnoses,from both East and West,converge on the view that we are living through a turbulent juncture reminiscent of the inflection points that preceded major wars,not as a claim of historical symmetry,but a... Multiple diagnoses,from both East and West,converge on the view that we are living through a turbulent juncture reminiscent of the inflection points that preceded major wars,not as a claim of historical symmetry,but as an indication of the depth of the present crisis.What concerns us here is to affirm the essence of that assessment:we are indeed facing an unprecedented crisis that compels a rethinking of the entire existing international order,as U.S. 展开更多
关键词 turbulent juncture global south international order Arab perspective global governance rethinking CRISIS unprecedented crisis
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Impacts of 1.5℃ and 2.0℃ Global Warming on the Onset,Cessation,and Length of the Rainy Season in Global Land Monsoon Regions
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作者 Thierry N.TAGUELA Ibraheem RAJI +4 位作者 Akintomide A.AKINSANOLA Priyanshi SINGHAI Oluwafemi E.ADEYERI Caroline M.WAINWRIGHT Rondrotiana BARIMALALA 《Advances in Atmospheric Sciences》 2026年第1期87-102,共16页
The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.... The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.In this study,we analyze how global warming levels(GWLs)of 1.5℃ and 2℃ could affect the timing of rainfall onset(RODs),rainfall cessation(RCDs),and the overall duration of the rainy season(LRS)over global land monsoon(GLM)regions using simulations from CMIP6 under the SSP2-4.5 and SSP5-8.5 scenarios.With high model consensus,our results reveal that RODs are projected to occur later over Southern Africa,North Africa,and South America,but earlier over South Asia and Australia,in a warmer climate.The projected early RODs in Australia are more pronounced at the 2℃ GWL under SSP5-8.5.On the other hand,early RCDs are projected over South America and East Asia,while late RCDs are projected over North Africa,with high inter-model agreement.These changes are associated with a future decrease in LRS in most GLM regions.Additionally,we found that continuous warming over 1.5℃ will further reduce the length of the rainy season,especially over the South America,North Africa,and Southern Africa monsoon regions.The findings underscore the urgent need to mitigate global warming. 展开更多
关键词 rainfall onset rainfall cessation global land monsoon rainy season length CMIP6 projections global warming levels
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Towards a Cooperative Global Future——China’s Global Governance Initiative lays emphasis on concrete actions aimed at promoting peace and development rather than on symbolic declarations
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作者 BUSANI NGCAWENI 《ChinAfrica》 2026年第2期16-17,共2页
As we enter the year 2026,the international system continues to receive shocks from Donald Trump,arguably the 21st century’s most disruptive US leader.His return to the White House in 2025 coincided with the 80th ann... As we enter the year 2026,the international system continues to receive shocks from Donald Trump,arguably the 21st century’s most disruptive US leader.His return to the White House in 2025 coincided with the 80th anniversary of the defeat of fascism and the establishment of the United Nations,the multilateral platform that carried the world’s hope for peace,restraint and collective security.The coincidence was unsettling.A world order designed to limit power now confronts a moment in which power is exercised openly,transactionally and unapologetically. 展开更多
关键词 multilateral platform cooperative global future development Donald Trump united nationsthe PEACE Chinas global governance initiative symbolic declarations
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