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Self-organized criticality of liquefaction in saturated granules 被引量:1
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作者 吴爱祥 孙业志 李青松 《中国有色金属学会会刊:英文版》 CSCD 2003年第1期180-184,共5页
Utilizing the dissipative structure theory, the evolutionary process of vibrating liquefaction in saturated granules was analyzed. When the irreversible force increases to some degree, the system will be in a state fa... Utilizing the dissipative structure theory, the evolutionary process of vibrating liquefaction in saturated granules was analyzed. When the irreversible force increases to some degree, the system will be in a state far from equilibrium, and the new structure probably occurs. According to synergetics, the equation of liquefaction evolution was deduced, and the evolutionary process was analyzed by dynamics. The evolutionary process of vibrating liquefaction is a process in which the period doubling accesses to chaos, and the fluctuation is the original driving force of system evolution. The liquefaction process was also analyzed by fractal geometry. The steady process of vibrating liquefaction obeys the scaling form, and shows self-organized criticality in the course of vibration. With the increment of the recurrence number, the stress of saturated granules will decrease rapidly or lose completely, and the strain will increase rapidly, so that the granules can not sustain load and the "avalanche" phenomenon takes place. 展开更多
关键词 自组织临界 耗散结构 饱和颗粒 振荡液化
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Complexity and Self-Organized Criticality of Solid Earth System(Ⅰ)
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作者 Yu Chongwen Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1998年第1期30-47,共18页
The author puts forward the proposition of Complexity and Self Organized Criticality of Solid Earth System in the light of: (1) the science of complexity studies the mechanisms of emergence of complexity and is... The author puts forward the proposition of Complexity and Self Organized Criticality of Solid Earth System in the light of: (1) the science of complexity studies the mechanisms of emergence of complexity and is the science of the 21st century, (2) the study of complexity of the earth system would be one of the growing points occupying a strategic position in the development of geosciences in the 21st century. By the proposition we try to cogitate from a new viewpoint the ancient yet ever new solid earth system. The author abstracts the fundamental problem of the solid earth system from the essence of the generalized geological systems and processes which reads: the complexity and self organized criticality of the global nature, structure and dynamical behavior of the whole solid earth system emerging from the multiple coupling and superposition of non linear interactions among the multicomponents of the earths material and the multiple generalized geological (geological, geophysical, and geochemical) processes . Starting from this cognizance the author proposes eight major themes and the methodology of researches on the complexity and self organized criticality of the solid earth system. 展开更多
关键词 COMPLEXITY self organization self organized criticality the solid earth system FRACTAL chaos long range spatio temporal correlation fractal spatio temporal structure.
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The Research of Transmission Network Planning Based on System’s Self-organized Criticality
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作者 Zheng-yu Shu Chang-hong Deng +1 位作者 Wen-tao Huang Yi-xuan Weng 《Energy and Power Engineering》 2013年第4期902-905,共4页
This paper presents a new line importance degree evaluation index for the propagation of cascading failures, which is used to quantify transmission lines for cascade spread. And propose an improved capital matching mo... This paper presents a new line importance degree evaluation index for the propagation of cascading failures, which is used to quantify transmission lines for cascade spread. And propose an improved capital matching model, according to the results of the evaluation, to enhanced robustness of the power system. The simulation results proved that in the case of the same system, the new model can inhibit cascade spread, reduce the probability of large-scale blackouts. 展开更多
关键词 Transmission LINE Assessment self-organized criticality CASCADE LOAD Distribution
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Lévy Flights, 1/<i>f </i>Noise and Self Organized Criticality
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作者 Oliver López Corona Pablo Padilla +2 位作者 Oscar Escolero Alejandro Frank Ruben Fossion 《Journal of Modern Physics》 2013年第3期337-343,共7页
A new analysis of a previously studied traveling agent model, showed that there is a relation between the degree of homogeneity of the medium where the agents move, agent motion patterns, and the noise generated from ... A new analysis of a previously studied traveling agent model, showed that there is a relation between the degree of homogeneity of the medium where the agents move, agent motion patterns, and the noise generated from their displacements. We proved that for a particular value of homogeneity, the system self organizes in a state where the agents carry out Lévy walks and the displacement signal corresponds to 1/f noise. Using probabilistic arguments, we conjectured that 1/f noise is a fingerprint of a statistical phase transition, from randomness (disorder) to predictability (order), and that it emerges from the contextuality nature of the system which generates it. 展开更多
关键词 Lévy FLIGHTS 1/f Noise self organized criticality Agents Modelling Complexity
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Electrical Tree Simulation Based on the Self-Organization Criticality
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作者 H. M. Hu Y. Yang +1 位作者 W. Lu G. P. Zhao 《Energy and Power Engineering》 2013年第4期1273-1276,共4页
So far much effort has been made to understand the development of electrical treeing. For the simulation based study of electrical treeing, the most common method is to apply DBM stochastic model to simulate the growi... So far much effort has been made to understand the development of electrical treeing. For the simulation based study of electrical treeing, the most common method is to apply DBM stochastic model to simulate the growing of electrical treeing patterns. Previous simulation results showed that this stochastic model is capable of simulating the real electrical treeing patterns in a point-to-plane electrode system. However, this model only allows the tree channels to propagate on equipotential lines proportional to local electrical field. Therefore, it is necessary to develop a novel stochastic model to simulate the electrical patterns in order to get a good agreement with experimental results. 展开更多
关键词 FRACTAL Electrical TREE SIMULATION self-organIZATION criticality
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Self-organized criticality of forest fires in China 被引量:15
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作者 Song Weiguo Fan Weicheng Wang Binghong 《Chinese Science Bulletin》 SCIE EI CAS 2001年第13期1134-1137,共4页
Self-organized criticality(SOC) of forest fires in China from 1950 to 1989 is studied. The stability, scale-invariant character of SOC and external effects on SOC of forest fires in China are analyzed in detail. Fores... Self-organized criticality(SOC) of forest fires in China from 1950 to 1989 is studied. The stability, scale-invariant character of SOC and external effects on SOC of forest fires in China are analyzed in detail. Forest-fire cellular automata model is a typical model for the research of SOC. Based on the traditional forest-fire model, an improved model, in which effects of tree species, meteorological conditions and human efforts on forest fires are considered, is introduced. Actual forest fire data in China are compared with simulation results of the two models. It is shown that forest fire data in China have SOC behavior and simulation results of the improved model accord better with actual forest fire data than those of the traditional model. 展开更多
关键词 self-organized criticality CELLULAR AUTOMATA forest-fire model FIRE science.
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On power system blackout modeling and analysis based on self-organized criticality 被引量:10
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作者 MEI ShengWei XUE AnCheng ZHANG XueMin 《Science China(Technological Sciences)》 SCIE EI CAS 2008年第2期209-219,共11页
This paper makes a comprehensive survey on power system blackout modeling and analysis based on SOC (self-organized criticality). Firstly,a generalized SOC theory from the viewpoint of cybernetics is introduced. Then ... This paper makes a comprehensive survey on power system blackout modeling and analysis based on SOC (self-organized criticality). Firstly,a generalized SOC theory from the viewpoint of cybernetics is introduced. Then the evolution model of power system and its relative mathematical description,which serves as a concrete example of the proposed generalized SOC,are given. Secondly,five blackout models capturing various critical properties of power systems in different time-scales are listed. Finally,this paper analyzes SOC in power systems,such as,the revelation of criticalities of proposed models in both micro-scale and macro-scale which can be used to assess the security of power system,and cas-cading failures process. 展开更多
关键词 BLACKOUT model self-organized criticality (SOC) CASCADING FAILURES
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Self-organized criticality judgment and extreme statistics analysis of major urban fires 被引量:6
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作者 WANG JingHong XIE Shu SUN JinHua 《Chinese Science Bulletin》 SCIE EI CAS 2011年第6期567-572,共6页
The spatial (economic loss) and temporal characteristics of urban fires were analyzed employing relevant statistical methods. A fractal structure in terms of the power-law relation between fire frequency and economic ... The spatial (economic loss) and temporal characteristics of urban fires were analyzed employing relevant statistical methods. A fractal structure in terms of the power-law relation between fire frequency and economic loss was found on a spatial scale, and an exponential relation between frequency and time interval was found on a temporal scale. Thus, urban fire does not meet the rigorous criteria of self-organized criticality. In addition, based on the spatial power-law distribution characteristics, a correlation model of the frequency and scale of loss due to urban fire was established using the extremum statistical method. This model was then applied to the case analysis of Hefei and the probability of major fire incidents in the future was predicted. 展开更多
关键词 自组织临界性 城市火灾 统计分析 统计方法 时空特征 经济损失 时间尺度 相关模型
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Self-organized criticality of power system faults and its application in adaptation to extreme climate 被引量:4
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作者 SU Sheng LI YinHong DUAN XianZhong 《Chinese Science Bulletin》 SCIE EI CAS 2009年第7期1251-1259,共9页
This paper analyzes the statistics of faults in a transmission and distribution networks in central China, unveils long-term autocorrelation and power law distribution of power system faults, which indicates that powe... This paper analyzes the statistics of faults in a transmission and distribution networks in central China, unveils long-term autocorrelation and power law distribution of power system faults, which indicates that power system fault has self-organized criticality (SOC) feature. The conclusion is consistent with the power systems data in 2008 with ice storm present. Since power systems cover large areas, climate is the key factor to its safety and stability. In-depth analysis shows that the SOC of atmosphere system contributes much to that of power system faults. Extreme climate will be more intense and frequent with global warming, it will have more and more impact upon power systems. The SOC feature of power system faults is utilized to develop approaches to facilitate power systems adaptation to climate variation in an economical and efficient way. 展开更多
关键词 电力系统故障 自组织临界性 极端气候 应用 全球气候变暖 配电网络 统计数据 华中地区
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POWER LAW DISTRIBUTION AND SELF-ORGANIZED CRITICALITY OF DISPERSED PARTICLES 被引量:1
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作者 Degang Ma Lihe Chai 《China Particuology》 SCIE EI CAS CSCD 2005年第4期237-239,共3页
Research on particulate characteristics has been an important frontier in physics and chemistry during the past decades. It has however been mostly focused on granular materials with short-range interactions. In this ... Research on particulate characteristics has been an important frontier in physics and chemistry during the past decades. It has however been mostly focused on granular materials with short-range interactions. In this work, it was found that the power law of particle size distribution applied to the long-range interacting system of floating dust in air, from which we deduced that self-organized criticality might hold for floating dust just as granular materials with short-range interactions. This feature may reveal underlying kinetic mechanisms, important in dispersed particle systems. In industry, power law of size distribution of dispersed particles can be used to investigate the change of dust size, and the power law parameter could be taken as an important index for dust separation. 展开更多
关键词 dispersed particle floating dust self-organized criticality power law
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Self-organized Criticality Behavior in Bulk Metallic Glasses
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作者 Jun-wei QIAO Zhong WANG 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第1期7-13,共7页
Serrated flows are known as repeated yielding of bulk metallic glasses(BMGs)during plastic deformation under different loading conditions,which are associated with the operation of shear banding.According to the sta... Serrated flows are known as repeated yielding of bulk metallic glasses(BMGs)during plastic deformation under different loading conditions,which are associated with the operation of shear banding.According to the statistics of some parameters,the shear avalanches can display a self-organized critical state,suggesting a large ductility of BMGs.The emergence of the self-organized criticality(SOC)behavior in different BMGs is due to the temperature,strain rate,and chemical compositions.The SOC behavior is accompanied with the following phenomena:the interactions occur in the shear bands;the incubation time is longer than the relaxation time;the time interval is lacking of typical time scale;and the spatial or temporal parameters should display apower-law distribution. 展开更多
关键词 self-organized criticality behavior bulk metallic glass serrated flow power-law distribution
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Self-organization criticality of debris flow rheology 被引量:5
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作者 WANGYuyi JANChyandeng +1 位作者 CHENXiaoqing HANwenliang 《Chinese Science Bulletin》 SCIE EI CAS 2003年第17期1857-1861,共5页
Based on the viewpoint of stress and strain self-organization criticality of debris flow mass, this paper probes into inter-nonlinear action between different factors in the thixotropic liquefaction system of loose cl... Based on the viewpoint of stress and strain self-organization criticality of debris flow mass, this paper probes into inter-nonlinear action between different factors in the thixotropic liquefaction system of loose clastic soil on slope to make clastic soil in slope develop naturally towards critical stress status, and slope debris flow finally occurs under trigging by rainstorm. Also according to observation and analysis of self-organization criticality of sediment run-off system of viscous debris flow surges in ravines and power relation between magnitude and frequency of debris flows, this paper expounds similarity of the self-organized structure of debris flow mass. The self-organized critical system is a weak chaotic system. Debris flow occurrences can be pre-dicted accordingly by means of observation at certain time scale and analysis of self-organization criticality of magni-tude, frequency and time interval of debris flows. 展开更多
关键词 泥石流 流变学 自组织危险程度 触变液化系统
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Influences of finite-size effects on the self-organized critical-ity of forest-fire model 被引量:9
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作者 Weiguo Song Weicheng Fan Binghong Wang 《Chinese Science Bulletin》 SCIE EI CAS 2002年第3期177-180,共4页
The influences of finite-size effects on the self-organized criticality (SOC) of the traditional forest-fire model are investigated by means of a new method. The forest size is originally set to a value much greater t... The influences of finite-size effects on the self-organized criticality (SOC) of the traditional forest-fire model are investigated by means of a new method. The forest size is originally set to a value much greater than the correla-tion length of the forest. Finite-size effects are then studied by equally dividing the forest into more and more separate subsystems on condition that the forest size, igniting prob-ability and planting probability are invariant. A new phe-nomenon, i.e. the finite-size effects with one-side frequency peak, is observed. The boundary between two neighboring subsystems can be regarded as a firebreak. The concept of ’separation ability’ is introduced to represent the probability for the firebreak to block off the fire successfully. Restrain-ing effects of separation ability on finite-size effects are ana-lyzed. Finite-size effects and separation ability, as well as their relations are found to have practical importance to the actual forest-fire protection. 展开更多
关键词 forest-fire model self-organized criticality cellular AUTOMATA FINITE-SIZE effects.
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Al-4%Cu多晶合金中锯齿形屈服现象的初步时序分析 被引量:7
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作者 卢俊勇 蒋震宇 张青川 《金属学报》 SCIE EI CAS CSCD 北大核心 2006年第6期611-618,共8页
对Al-4%Cu合金试样拉伸实验的锯齿形应力曲线进行了系统的统计分析,研究了锯齿应力跌幅、跌落时间以及再加载时间等特征物理量随应变、试样厚度和加载应变率的时序演化规律.结果表明,跌落时间对应变不敏感; 1和2 mm厚试样的平均应力... 对Al-4%Cu合金试样拉伸实验的锯齿形应力曲线进行了系统的统计分析,研究了锯齿应力跌幅、跌落时间以及再加载时间等特征物理量随应变、试样厚度和加载应变率的时序演化规律.结果表明,跌落时间对应变不敏感; 1和2 mm厚试样的平均应力跌幅和平均再加载时间均随应变线性增加, 3 mm厚试样的统计结果比较复杂.展示了PLC效应中自组织临界性存在的证据,并通过与经典沙堆模型的对比,结合动态应变时效原理和位错理论,解释了PLC变形带形成的非线性机制. 展开更多
关键词 Al—Cu合金 锯齿形屈服效应 统计分析 自组织临界性
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输电网-配电网-微电网三级电网规划的若干基础问题 被引量:21
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作者 梅生伟 王莹莹 《电力科学与技术学报》 CAS 2009年第4期3-11,共9页
根据国内外电力系统发展趋势及电力工业面临的实际问题,明确提出输电网-配电网-微电网三网合一的未来电网规划设计重大基础问题,进一步提出将复杂网络理论的概念和方法加以发展从而应用于新一代三级电网的规划设计的研究思路.研究涉及... 根据国内外电力系统发展趋势及电力工业面临的实际问题,明确提出输电网-配电网-微电网三网合一的未来电网规划设计重大基础问题,进一步提出将复杂网络理论的概念和方法加以发展从而应用于新一代三级电网的规划设计的研究思路.研究涉及三类基础课题:一是三级电网的宏观形态及概念设计;二是三级电网结构理论基本框架;三是基于自组织临界理论(Self-Organized Criticality,SOC)的三级电网规划方法.全面阐述了规划和建设三级电网的必要性和迫切性,明确指出三级电网是未来电网的主要发展方向之一. 展开更多
关键词 三级电网 自组织临界理论 分布式发电 电网演化机制模型
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孕震断层锁固段累积损伤导致失稳的自组织-临界行为特征 被引量:4
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作者 吴晓娲 秦四清 +2 位作者 薛雷 杨百存 张珂 《物理学报》 SCIE EI CAS CSCD 北大核心 2018年第20期417-426,共10页
弄清锁固段(岩石)破裂过程中自组织临界性的物理涵义,对正确认识地震可预测性问题等具有重要意义.本文指出锁固段破裂过程存在两个临界点,第一临界点为体积膨胀点,是自组织过程起点,在该点锁固段发生可判识的高能级破裂事件,这可视为锁... 弄清锁固段(岩石)破裂过程中自组织临界性的物理涵义,对正确认识地震可预测性问题等具有重要意义.本文指出锁固段破裂过程存在两个临界点,第一临界点为体积膨胀点,是自组织过程起点,在该点锁固段发生可判识的高能级破裂事件,这可视为锁固段宏观破裂前的惟一可识别前兆;第二临界点为峰值强度点,即失稳点,在该点发生通常有明显地表破裂带的大地震.基于以前研究给出的两者之间应变比理论关系以及地震震级与能量约束关系,可预测锁固段在第一和第二临界点处发生的某些标志性地震,并已得到诸多震例分析的支持.本文研究结果表明:由于锁固段是非均匀介质,其失稳前必须出现自组织过程,自组织是"因",临界失稳是"果",正是因为自组织过程的存在,才使得对某些大地震(如标志性地震)的预测成为可能;两个临界点之间的破裂演化过程并不是瞬态行为,通常是一个长期过程,该过程中标志性地震的发生遵循确定性规律,并不存在小地震直接导致大地震(如标志性地震)的级联效应. 展开更多
关键词 自组织 临界失稳 沙堆模型 锁固段
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COVID-19期间区域大气高污染发生的非线性动力机制 被引量:8
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作者 吴波 刘春琼 +6 位作者 张娇 李彦辉 陈郁兵 文烨 鲍冰逸 杜娟 史凯 《中国环境科学》 EI CAS CSCD 北大核心 2021年第5期2028-2039,共12页
以长株潭城市群3个城市(长沙、株洲和湘潭)疫情期间(2020年1月24日~2020年5月31日)大气PM_(2.5)和O_(3)小时平均浓度时间序列数据为研究对象,对污染物日变化规律、长期持续性、多重分形性及自组织演化动力学特性进行研究.以期阐释疫情... 以长株潭城市群3个城市(长沙、株洲和湘潭)疫情期间(2020年1月24日~2020年5月31日)大气PM_(2.5)和O_(3)小时平均浓度时间序列数据为研究对象,对污染物日变化规律、长期持续性、多重分形性及自组织演化动力学特性进行研究.以期阐释疫情期间高污染事件发生及演化的内在动力机制.首先,对3个城市PM_(2.5)和O_(3)质量浓度的日变化规律进行分析,发现O_(3)呈现出昼高夜低的单峰型,而PM_(2.5)日变化规律表现出昼低夜高单峰型,与非疫情期间的特征有所差异.进一步,应用消除趋势波动分析法(DFA)、多重分形消除趋势波动分析法(MFDFA)和概率统计分析,研究了大气复合系统中PM_(2.5)和O_(3)质量浓度序列的长期持续性和多重分形结构.结果发现3个城市PM_(2.5)和O_(3)浓度序列均具有显著的长期持续性特征和较强的多重分形结构,同时,应用去趋势互相关分析法(DCCA)方法和多重分形去趋势互相关分析法(MFDCCA)对PM_(2.5)和O_(3)两者之间的互相关性进行了分析,发现PM_(2.5)-O_(3)之间的互相关也存在显著的长期持续性特征以及在不同时间尺度存在多重分形特征.进一步将疫情期间得到的非线性分析结果与2018年和2019年同期非疫情期间的结果进行了对比分析.最后,基于自组织临界理论(SOC)探讨了大气PM_(2.5)和O_(3)浓度时空演化的内在动力规律,并结合典型区域气象特征,阐明了SOC内禀动力机制可能是COVID-19疫情期间大气高污染形成的主导机制之一.疫情期间大气PM_(2.5)和O_(3)浓度并非分别独自演化,而是依然保持复杂的相互作用.静稳气象条件下,大气复合污染内部的非线性耦合作用可能达到动力学临界状态,将导致长株潭城市群在疫情期间仍有发生大气高污染的风险. 展开更多
关键词 日变化规律 长期持续性 多重分形 幂律统计 自组织临界 PM_(2.5) O3
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COVID-19疫情期间城郊森林公园O_(3)变化对NO_(2)减排响应的多重分形模式 被引量:5
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作者 张娇 刘春琼 +2 位作者 吴波 杜娟 史凯 《生态学报》 CAS CSCD 北大核心 2021年第24期9669-9680,共12页
COVID-19疫情的爆发使得大气NO_(2)排放量急剧减少,张家界城区O_(3)浓度也随之降低,然而城郊的国家森林公园内O_(3)浓度却有较大幅度升高。旨在基于多重分形去趋势互相关分析(MFDCCA)方法和自组织临界(SOC)理论来揭示疫情期间张家界不... COVID-19疫情的爆发使得大气NO_(2)排放量急剧减少,张家界城区O_(3)浓度也随之降低,然而城郊的国家森林公园内O_(3)浓度却有较大幅度升高。旨在基于多重分形去趋势互相关分析(MFDCCA)方法和自组织临界(SOC)理论来揭示疫情期间张家界不同生态功能区大气O_(3)浓度变化对NO_(2)污染急剧减排的不同响应机制。基于张家界3个大气监测站点(未央路、永定新区和袁家界)在疫情期间(2020年3月1日—5月31日)和非疫情期间(2019年同期)NO_(2)、O_(3)小时平均浓度数据,首先应用MFDCCA方法对NO_(2)和O_(3)互相关性的多尺度特征进行分析。研究结果发现,各站点NO_(2)和O_(3)之间的互相关性存在较强的长期持续性和多重分形特征。其中,疫情期间各站点NO_(2)和O_(3)互相关的长期持续性平均增强了19.4%,而多重分形性平均减弱5.7%,主要原因与疫情期间NO_(2)集中减排引起O_(3)大气化学反应的变化有关。进而,应用SOC理论对NO_(2)和O_(3)之间互相关长期持续性形成的宏观动力机制进行分析。结果发现,袁家界站点O_(3)演化处于自组织临界状态,SOC内禀动力机制是导致疫情期间张家界国家森林公园内O_(3)浓度增高的重要非线性动力学机制。而未央路和永定新区站点O_(3)演化处于亚临界状态,这也是导致城区站点O_(3)浓度减低的主要原因。正确识别森林生态系统中O_(3)演化的自组织临界特征,对于高浓度O_(3)生成的风险评估具有重要意义,有助于科学评估人类旅游活动对森林生态系统造成的影响。 展开更多
关键词 新型冠状病毒肺炎 多重分形去趋势互相关分析 自组织临界理论 长期持续性特征
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基于沙堆模型的国家动力学研究--以中国历史为例(前221年到1912年)
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作者 吕鹏 李蒙迪 张卓 《社会研究方法评论》 2022年第2期43-79,共37页
关于帝国兴衰,长期存在的“超稳定结构”理论并不能呈现动态的历史过程。复杂性学科的“自组织临界性”理论,能够模拟帝国兴衰的动态过程,并对“超稳定结构说”形成补充。自然系统(沙堆模型)与社会系统类似,都在自动、自发地趋近临界状... 关于帝国兴衰,长期存在的“超稳定结构”理论并不能呈现动态的历史过程。复杂性学科的“自组织临界性”理论,能够模拟帝国兴衰的动态过程,并对“超稳定结构说”形成补充。自然系统(沙堆模型)与社会系统类似,都在自动、自发地趋近临界状态,我们可以通过社会计算模型揭示帝国兴衰的动力学机制。研究目标,是精准拟合中国大历史,即秦汉到明清的2132年的农业帝国兴衰演变史,包括朝代数量、朝代寿命等客观指标,使用具体智能体ABM模型,建构代表帝国社会有机体的沙堆模型。通过参数遍历仿真,求解最优的参数解。基于最优解,重复模拟1000次,求取均值获得稳健性结果。研究表明:第一,沙堆模型具有拟合有效性。中国历史上有22个朝代,沙堆模型可以“涌现”相同数量的朝代或帝国,而且数量遵循正态分布(平均值是22)。第二,沙堆模型具有重复稳健性。朝代寿命遵循幂律分布,模拟结果与真实历史呈现高度吻合。第三,沙堆模型具有可推广性。同样可以刻画非22帝国情况。22朝代是公认标准,但历史存在非线性、偶然性。因此需要拟合数量不等于22的情况。舍弃历史上1~3个短寿朝代,构建19、20、21组历史与仿真朝代队列,依然实现高精确度拟合。在23、24、25个仿真朝代中,舍弃1~3个短寿者,构成22组历史与仿真朝代,拟合度同样良好。沙堆模型对帝国兴衰历史、当前中美大国博弈,具有借鉴与指导意义。 展开更多
关键词 智能体建模(ABM) 帝国动力学 历史周期 组织临界性
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基于EEMD-MFDFA的镇江港PM_(2.5)演化特征分析 被引量:1
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作者 郑敏学 毛静 +4 位作者 孙智灏 朱龙 李志坚 居珍 黄爱国 《江苏大学学报(自然科学版)》 CAS 北大核心 2023年第6期738-744,共7页
为定量分析镇江港PM_(2.5)浓度时间序列的内在演化特征,以镇江港2019—2020年的205667组PM_(2.5)时均浓度数据为基础,采用基于集合经验模态分解(EEMD)的多重分形去趋势波动分析(MFDFA)算法进行研究.结果表明:各监测点PM_(2.5)日均浓度... 为定量分析镇江港PM_(2.5)浓度时间序列的内在演化特征,以镇江港2019—2020年的205667组PM_(2.5)时均浓度数据为基础,采用基于集合经验模态分解(EEMD)的多重分形去趋势波动分析(MFDFA)算法进行研究.结果表明:各监测点PM_(2.5)日均浓度演化均具有显著的长期持续性特征,现阶段PM_(2.5)浓度升高可能会导致未来一段时间内PM_(2.5)浓度的持续升高,不同监测点PM_(2.5)浓度的多重分形谱参数存在差异性,多重分形特征强的区域应侧重即时性防治,反之则应注重长期性监管;运用自组织临界性理论,发现15个监测点PM_(2.5)浓度波动呈现幂律分布特征,符合自组织临界性特征,港口系统存在发生大气高污染的风险. 展开更多
关键词 PM_(2.5) 镇江港 集合经验模态分解 多重分形去趋势波动分析 自组织临界理论
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