期刊文献+
共找到7篇文章
< 1 >
每页显示 20 50 100
Eigen microstates and their evolutions in complex systems 被引量:7
1
作者 Yu Sun Gaoke Hu +6 位作者 Yongwen Zhang Bo Lu Zhenghui Lu jingfang fan Xiaoteng Li Qimin Deng Xiaosong Chen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第6期140-157,共18页
Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evol... Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evolution of complex system.In this framework,the statistical ensemble composed of M microstates of a complex system with N agents is defined by the normalized N×M matrix A,whose columns represent microstates and order of row is consist with the time.The ensemble matrix A can be decomposed as■,where r=min(N,M),eigenvalueσIbehaves as the probability amplitude of the eigen microstate U_I so that■and U_I evolves following V_I.In a disorder complex system,there is no dominant eigenvalue and eigen microstate.When a probability amplitudeσIbecomes finite in the thermodynamic limit,there is a condensation of the eigen microstate UIin analogy to the Bose–Einstein condensation of Bose gases.This indicates the emergence of U_I and a phase transition in complex system.Our framework has been applied successfully to equilibrium threedimensional Ising model,climate system and stock markets.We anticipate that our eigen microstate method can be used to study non-equilibrium complex systems with unknown orderparameters,such as phase transitions of collective motion and tipping points in climate systems and ecosystems. 展开更多
关键词 complex system phase transition critical phenomena Earth system statistical ensemble eigen microstate dynamic evolution ECONOPHYSICS
原文传递
Discontinuous and continuous transitions of collective behaviors in living systems 被引量:1
2
作者 Xu Li Tingting Xue +6 位作者 Yu Sun jingfang fan Hui Li Maoxin Liu Zhangang Han Zengru Di Xiaosong Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第12期160-166,共7页
Living systems are full of astonishing diversity and complexity of life.Despite differences in the length scales and cognitive abilities of these systems,collective motion of large groups of individuals can emerge.It ... Living systems are full of astonishing diversity and complexity of life.Despite differences in the length scales and cognitive abilities of these systems,collective motion of large groups of individuals can emerge.It is of great importance to seek for the fundamental principles of collective motion,such as phase transitions and their natures.Via an eigen microstate approach,we have found a discontinuous transition of density and a continuous transition of velocity in the Vicsek models of collective motion,which are identified by the finite-size scaling form of order-parameter.At strong noise,living systems behave like gas.With the decrease of noise,the interactions between the particles of a living system become stronger and make them come closer.The living system experiences then a discontinuous gas-liquid like transition of density.The even stronger interactions at smaller noise make the velocity directions of the particles become ordered and there is a continuous phase transition of collective motion in addition. 展开更多
关键词 living systems phase emergence phase transitions eigen mircostate
原文传递
Occurrence Regularity and Control Measures of Powdery Mildew in Strawberry
3
作者 Hui DONG Li LI +3 位作者 jingfang fan Li YANG Lei YANG Yanan LI 《Asian Agricultural Research》 2020年第9期60-61,72,共3页
Powdery mildew is a major disease of strawberry.It harms both plants and fruits,seriously affecting the quality and yield of strawberry.This article briefly introduces the harms and occurrence regularity of powdery mi... Powdery mildew is a major disease of strawberry.It harms both plants and fruits,seriously affecting the quality and yield of strawberry.This article briefly introduces the harms and occurrence regularity of powdery mildew in strawberry and summarizes the corresponding control measures,with a view to providing a certain scientific reference for the prevention and treatment of the disease. 展开更多
关键词 Powdery mildew in strawberry HARM Occurrence regularity Control measure
在线阅读 下载PDF
Complexity science meets Earth system 被引量:1
4
作者 jingfang fan Jun Meng +1 位作者 Xiaosong Chen Hans Joachim Schellnhuber 《Science Bulletin》 2025年第1期19-24,共6页
The Earth’s climate system operates across multiple scales,driven by intricate interactions among natural processes and human activities.Understanding these dynamics is crucial for predicting future climate scenarios... The Earth’s climate system operates across multiple scales,driven by intricate interactions among natural processes and human activities.Understanding these dynamics is crucial for predicting future climate scenarios(days to decades)and their impacts on global environments and societies.These interactions span across atmospheric circulation,ocean currents,geological processes,and biological systems,influencing global climate variability and regional weather patterns[1]. 展开更多
关键词 EARTH CLIMATE WEATHER
原文传递
Eigen microstate analysis unveils climate dynamics
5
作者 Hua Tu Shang Wang +4 位作者 Jun Meng Yongwen Zhang Xiaosong Chen Deliang Chen jingfang fan 《Science China(Physics,Mechanics & Astronomy)》 2025年第4期91-100,共10页
The Earth's climate operates as a complex,dynamically interconnected system,driven by both anthropogenic and natural forcings and modulated by nonlinear interactions and feedback loops.This study employs a theoret... The Earth's climate operates as a complex,dynamically interconnected system,driven by both anthropogenic and natural forcings and modulated by nonlinear interactions and feedback loops.This study employs a theoretical framework and the Eigen Microstate(EM)approach of statistical physics to examine global surface temperature variations since 1948,as revealed by a global reanalysis.We identified EMs significantly correlated with key climate phenomena such as the global monsoon system,tropical climates,and El Niño.Our analysis reveals that these EMs have increasingly influenced global surface temperature variations over recent decades,highlighting the critical roles of hemispheric differences,land-sea contrasts,and tropical climate fluctuations in a warming world.Additionally,we used model simulations from more than 10 Coupled Model Intercomparison Project Phase 6(CMIP6)under three future climate scenarios to perform a comparative analysis of the changes in each EM contribution.The results indicate that under future warming scenarios,tropical climate fluctuations will become increasingly dominant,while traditional hemispheric and monsoonal patterns may decline.This shift underscores the importance of understanding tropical dynamics and their impact on global climate from a physics-based perspective.Our study provides a new perspective on understanding and addressing global climate change,enhancing the theoretical foundation of this critical field,and yielding findings with significant practical implications for improving climate models and developing effective mitigation and adaptation strategies. 展开更多
关键词 statistical physics nonlinear dynamics complex systems climate change
原文传递
Network approaches to climate science
6
作者 jingfang fan Jun Meng +2 位作者 XiaoSong Chen Yosef Ashkenazy Shlomo Havlin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2017年第1期80-81,共2页
Climate and physics are closely related. The governing equa- tions for both the atmosphere and ocean are the Navier-Stokes equations, which describe and quantify the physics of fluids. However, the atmosphere and ocea... Climate and physics are closely related. The governing equa- tions for both the atmosphere and ocean are the Navier-Stokes equations, which describe and quantify the physics of fluids. However, the atmosphere and ocean are very complex due to the interaction of many processes, not necessarily physi- cal, and due to the need to model processes that are smaller than the grid resolution. In spite of this complexity, physi- cists have successfully addressed a wide swath of it using ad- vanced statistical physics methods and techniques. Climate science has been benefited from the physics discipline and vice versa where the "chaos" theory is an excellent example for the interdisciplinary approach as it was basically discov- ered by Lorenz [ 1 ] through his simple model of the atmos- phere. 展开更多
关键词 OCEAN SPITE STOKES quantify addressed necessarily NAVIER governing
原文传递
Universality class of machine learning for critical phenomena
7
作者 Gaoke Hu Yu Sun +5 位作者 Teng Liu Yongwen Zhang Maoxin Liu jingfang fan Wei Chen Xiaosong Chen 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2023年第12期63-70,共8页
Herein,percolation phase transitions on a two-dimensional lattice were studied using machine learning techniques.Results reveal that different phase transitions belonging to the same universality class can be identifi... Herein,percolation phase transitions on a two-dimensional lattice were studied using machine learning techniques.Results reveal that different phase transitions belonging to the same universality class can be identified using the same neural networks(NNs),whereas phase transitions of different universality classes require different NNs.Based on this finding,we proposed the universality class of machine learning for critical phenomena.Furthermore,we investigated and discussed the NNs of different universality classes.Our research contributes to machine learning by relating the NNs with the universality class. 展开更多
关键词 universality class machine learning PERCOLATION
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部