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Complex-Variable Fokker-Planck Equation Solved in Entangled State Representation
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作者 唐绪兵 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1049-1052,共4页
We lind that the Fokker-Planck equation in complex variables can be conveniently solved in the context of bipartite entangled state representation and its relationship with SU(2) Lie algebraic generators' new reali... We lind that the Fokker-Planck equation in complex variables can be conveniently solved in the context of bipartite entangled state representation and its relationship with SU(2) Lie algebraic generators' new realization {(1/4)[(Q1 - Q2)^2 + (P1+ P2)^2], (1/4)[(Q1 +Q2)^2+ (P1 - P2)^2], and -(i/2)(Q1P2 + Q2P1)}, the quadratic combination of canonical operators. 展开更多
关键词 Fokker planck equation entangled state representation SU(2) Lie algebra
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Constraining Equation of State of Dark Matter:Including Weak Gravitational Lensing
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作者 杨磊 杨维强 徐立昕 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第5期183-187,共5页
Usually the equation of state (EoS) of dark matter is zero when it is cold, however there exists the possibility of a (effective) nonzero EoS of dark matter due to its decay and interaction with dark energy. In th... Usually the equation of state (EoS) of dark matter is zero when it is cold, however there exists the possibility of a (effective) nonzero EoS of dark matter due to its decay and interaction with dark energy. In this work, we try to constrain the EoS of dark matter/JAdm using the currently available cosmic observations which include the geometrical and dynamical measurements. For the geometrical measurements, the luminosity distance of type Ia supernovae, the angular diameter distance and comoving sound horizon from baryon acoustic oscillations and the cosmic microwave background radiation will be employed. The data points from the redshift-space distortion and weak gravitational lensing will be taken as dynamical measurements. Using the Markov chain Monte Carlomethod, we obtain a very tight constraint on the-EoS of dark matter:wdm=0.0000532 +0.000692+0.00136+0.00183 -0.000686-0.00136-0.00177. 展开更多
关键词 In Constraining equation of state of Dark Matter:Including Weak Gravitational Lensing planck
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Maxwell’s Equations as the Basis for Model of Atoms
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作者 Milan Perkovac 《Journal of Applied Mathematics and Physics》 2014年第5期235-251,共17页
A century ago the classical physics couldn’t explain many atomic physical phenomena. Now the situation has changed. It’s because within the framework of classical physics with the help of Maxwell’s equations we can... A century ago the classical physics couldn’t explain many atomic physical phenomena. Now the situation has changed. It’s because within the framework of classical physics with the help of Maxwell’s equations we can derive Schr&ouml;dinger’s equation, which is the foundation of quantum physics. The equations for energy, momentum, frequency and wavelength of the electromagnetic wave in the atom are derived using the model of atom by analogy with the transmission line. The action constant A0 = (μ0/ε0)1/2s02e2 is a key term in the above mentioned equations. Besides the other well-known constants, the only unknown constant in the last expression is a structural constant of the atom s0. We have found that the value of this constant is 8.277 56 and that it shows up as a link between macroscopic and atomic world. After calculating this constant we get the theory of atoms based on Maxwell’s and Lorentz equations only. This theory does not require knowledge of Planck’s constant h, which is replaced with theoretically derived action constant A0, while the replacement for the fine structure constant α-1 is theoretically derived expression 2s02 = 137.036. So, the structural constant s0 replaces both constants h and α. This paper also defines the stationary states of atoms and shows that the maximal atomic number is equal to Zmax = 137. The presented model of the atoms covers three of the four fundamental interactions, namely the electromagnetic, weak and strong interactions. 展开更多
关键词 Action CONSTANT Fine Structure CONSTANT Lecher’s LINE Maxwell’s equations New ELEMENTS Phase Velocity planck’s CONSTANT Stability of ATOMS Standing Waves Stationary stateS Synchronized stateS System of the ELEMENTS STRUCTURAL Coefficient STRUCTURAL CONSTANT Transmission LINE Undiscovered ELEMENTS
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Planck尺度下Anti-de Sitter时空视界附近自旋场的热力学量
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作者 刘晓莹 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第6期40-44,共5页
在Planck尺度下,采用WKB近似方法计算了Anti-de Sitter时空视界附近自旋为1/2,1,2等自旋场的熵密度、压强和能量密度.结果表明,Anti-de Sitter时空附近的热力学量不仅依赖于黑洞的特征和纯时空效应,还依赖于粒子的自旋效应和最小距离的... 在Planck尺度下,采用WKB近似方法计算了Anti-de Sitter时空视界附近自旋为1/2,1,2等自旋场的熵密度、压强和能量密度.结果表明,Anti-de Sitter时空附近的热力学量不仅依赖于黑洞的特征和纯时空效应,还依赖于粒子的自旋效应和最小距离的尺度. 展开更多
关键词 AdS时空 自旋场 planckn尺度 热力学量
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非高斯噪声激励下非线性漂移Fokker-Planck方程的非稳态解及其应用 被引量:1
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作者 姚婷 郭永峰 +1 位作者 樊顺厚 魏芳 《工程数学学报》 CSCD 北大核心 2020年第3期303-313,共11页
非高斯噪声广泛存在于各种非线性系统,对非高斯噪声所驱动系统的非稳态演化行为进行研究可以更为深入的了解其内在的演化机理.本文对非高斯噪声和高斯白噪声共同驱动的非线性动力学系统的非稳态演化问题进行研究.首先应用格林函数的?展... 非高斯噪声广泛存在于各种非线性系统,对非高斯噪声所驱动系统的非稳态演化行为进行研究可以更为深入的了解其内在的演化机理.本文对非高斯噪声和高斯白噪声共同驱动的非线性动力学系统的非稳态演化问题进行研究.首先应用格林函数的?展开理论在初始区域对非线性动力学系统进行线性化,然后结合本征值和本征矢理论推导出了该系统Fokker-Planck方程的近似非稳态解的表达式,最后以Logistic系统模型为例分析了非高斯噪声强度,关联时间及非高斯噪声偏离参数对非稳态解以及一阶矩的影响.研究结果表明,用Logistic模型描述产品产量增长时,其非稳态解可更好地反映产品产量在不稳定点附近的演化行为. 展开更多
关键词 非高斯噪声 FOKKER-planck方程 非稳态解 LOGISTIC模型
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Aggregate modeling and analysis of air conditioning load using coupled Fokker–Planck equations 被引量:5
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作者 Dingyi CHENG Wen ZHANG Yutian LIU 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2018年第6期1277-1290,共14页
Demand response has gained significant attention recently with the increasing penetration of renewable energy sources in power systems. Air conditioning loads are typical thermostatically controlled loads which can pl... Demand response has gained significant attention recently with the increasing penetration of renewable energy sources in power systems. Air conditioning loads are typical thermostatically controlled loads which can play an active role in ancillary services by regulating their aggregated power consumption. The aggregation of air conditioners is essential to the control of air conditioning loads. In this paper, linear state equations are proposed to aggregate air conditioning loads by solving coupled Fokker–Planck equations(CFPEs) using the finite difference method. By analyzing the numerical stability and convergence of the difference scheme, the grid spacings, including temperature step and time step, are properly determined according to the maximal principle. Stationary solutions of the CFPEs are obtained by analytical and numerical methods. Furthermore, a classification method using dimension reduction is proposed to deal with the problem of heterogeneous parameters and interval estimation is applied to describe the stochastic behavior of air conditioning loads. The simulation results verify the effectiveness of the proposed methods. 展开更多
关键词 AGGREGATE model Air CONDITIONER COUPLED Fokker–planck equation Grid SPACING selection Heterogeneous Interval estimation Linear state equation Stationary solution
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双噪声系统的定态几率密度
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作者 周沧涛 张纪岳 彭圣儒 《湖南师范大学自然科学学报》 CAS 1991年第2期121-125,共5页
对于双噪声源的随机郎之万方程,在噪声均为OU噪声的情况下,从三维的FPE出发,利用类WKB方法,详细分析了双噪声源在其噪声强度均很小时对非平衡相变行为的影响,得到了定态几率密度的表达式。并从数值上分析了单模染料激光模型中的自发辐... 对于双噪声源的随机郎之万方程,在噪声均为OU噪声的情况下,从三维的FPE出发,利用类WKB方法,详细分析了双噪声源在其噪声强度均很小时对非平衡相变行为的影响,得到了定态几率密度的表达式。并从数值上分析了单模染料激光模型中的自发辐射噪声与泵浦噪声对非平衡相变的影响。 展开更多
关键词 双噪声系统 定态 概率密度
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稳态Poisson-Nernst-Planck方程的残量型后验误差估计
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作者 房明娟 阳莺 唐鸣 《计算数学》 CSCD 北大核心 2021年第1期17-32,共16页
针对稳态的Poisson-Nernst-Planck方程研究了一种残量型的后验误差估计子,对方程的两个解-浓度和电势,都分别给出了上界和下界估计.数值实验表明,基于这种后验误差估计子构造的自适应有限元算法对于稳态的Poisson-Nernst-Planck方程是... 针对稳态的Poisson-Nernst-Planck方程研究了一种残量型的后验误差估计子,对方程的两个解-浓度和电势,都分别给出了上界和下界估计.数值实验表明,基于这种后验误差估计子构造的自适应有限元算法对于稳态的Poisson-Nernst-Planck方程是有效的. 展开更多
关键词 稳态Poisson-Nernst-planck方程 后验误差估计子 残量型 上界 下界
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社会系统非平衡定态特性之系统方法研讨方略 被引量:5
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作者 聂云 《系统工程理论与实践》 EI CSCD 北大核心 1999年第10期20-26,共7页
运用系统方法理论研究社会系统取决于模型系统选取的合理程度. 由动力学变量决定的社会态函数所提供的信息可以定义Shannon 社会熵. 定态社会系统的产生熵可以描述社会系统的不可逆过程并且是一个很好的Ляпунов函数,... 运用系统方法理论研究社会系统取决于模型系统选取的合理程度. 由动力学变量决定的社会态函数所提供的信息可以定义Shannon 社会熵. 定态社会系统的产生熵可以描述社会系统的不可逆过程并且是一个很好的Ляпунов函数,它使我们对定态自组织的社会系统的整体稳定性充满自信.社会系统的Fokker-Planck 方程及其定态解的时间发展行为可以解释社会系统的非平衡相变. 尤以知识结构的创新对社会系统的发展壮大以致于出现非平衡相变都起着决定性的作用. 展开更多
关键词 社会系统 大系统 系统方法 非平衡相变
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