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一种三维Poisson-Nernst-Planck方程的虚单元计算
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作者 丁聪 刘杨 +1 位作者 阳莺 沈瑞刚 《吉林大学学报(理学版)》 CAS 北大核心 2024年第2期293-301,共9页
利用虚单元方法在多面体网格上求解一种三维稳态Poisson-Nernst-Planck(PNP)方程,并给出PNP方程的虚单元离散形式,推导电势方程及离子浓度方程的刚度矩阵与荷载向量的矩阵表达式.数值实验结果表明,在3种不同的多面体网格下实现了PNP方... 利用虚单元方法在多面体网格上求解一种三维稳态Poisson-Nernst-Planck(PNP)方程,并给出PNP方程的虚单元离散形式,推导电势方程及离子浓度方程的刚度矩阵与荷载向量的矩阵表达式.数值实验结果表明,在3种不同的多面体网格下实现了PNP方程的虚单元计算,数值解在L^(2)和H^(1)范数下均达到最优阶. 展开更多
关键词 Poisson-Nernst-planck方程 虚单元方法 多面体网格 三维
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Gedankenexperiment for Modified ZPE and Planck’s “Constant”, h, in the Beginning of Cosmological Expansion, Partly Due to NLED
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期180-184,共5页
We initially look at a non singular universe representation of entropy, based in part on what was brought up by Muller and Lousto. This is a gateway to bringing up information and computational steps (as defined by Se... We initially look at a non singular universe representation of entropy, based in part on what was brought up by Muller and Lousto. This is a gateway to bringing up information and computational steps (as defined by Seth Lloyd) as to what would be available initially due to a modified ZPE formalism. The ZPE formalism is modified as due to Matt Visser’s alternation of k (maximum) ~ 1/(Planck length), with a specific initial density giving rise to initial information content which may permit fixing the initial Planck’s constant, h, which is pivotal to the setting of physical law. The settings of these parameters depend upon NLED. 展开更多
关键词 ZPE planck’s “Constant” Gedankenexperiment NLED
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Elementary Fermions: Strings, Planck Constant, Preons and Hypergluons
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期82-100,共19页
Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism ... Using real fields instead of complex ones, it is suggested here that the fermions are pairs of coupled strings with an internal tension. The interaction between the two coupled strings is due to an exchange mechanism which is proportional to Planck’s constant. This may be the result of two massless bosons (hypergluons) coupled by a preon (prequark) exchange. It also gives a physical explanation to the origin of the Planck constant, and origin of spin. 展开更多
关键词 FERMIONS Preons Hypergluons Strings Real Fields planck Constant INTERFERENCE SPIN
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Curved Space-Time at the Planck Scale
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作者 Lewis Nash 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期167-179,共13页
This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the me... This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the metric tensor, is considered to be made up of a dynamic lattice of extremely small, localized fields that form a perfectly elastic Lorentz symmetric space-time at the global (macroscopic) scale. This theoretical model of space-time at the Planck scale leads to a somewhat surprising result in which matter waves in curved space-time radiate thermal gravitational energy, as well as an equally intriguing relationship for the anomalous dispersion of light in a gravitational field. 展开更多
关键词 Schwarzschild Space-Time Continuum Mechanics planck Lattice Gravitational Radiation
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God Time = Planck Time: Finally Detected! And Its Relation to Hubble Time
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作者 Espen Gaarder Haug 《Open Journal of Microphysics》 2024年第2期40-66,共27页
Newton already mentioned indivisible time in Principia. In 1899, Max Planck derived a unique time period from three universal constants: G, c, and ħ, and today this is known as the Planck time. The Planck time is of t... Newton already mentioned indivisible time in Principia. In 1899, Max Planck derived a unique time period from three universal constants: G, c, and ħ, and today this is known as the Planck time. The Planck time is of the order of about 10<sup>−44</sup> seconds while the best atomic clocks are down to 10<sup>−19</sup> seconds. An approach has recently been outlined that puts an upper limit on the quantization of time to 10<sup>−33</sup> seconds;this is, however, still far away from the Planck time. We demonstrate that the Planck time can easily be measured without any knowledge of any other physical constants. This is remarkable as this means we have demonstrated that the Planck time and therefore the Planck scale is real and detectable. It has taken more than 100 years to understand this. The reason for the breakthrough in Planck scale physics in recent years comes from understanding that G is a composite constant and that the true matter wavelength is the Compton wavelength rather than the de Broglie wavelength. When this is understood, the mysteries of the Planck scale can be uncovered. In this paper, we also demonstrate how to measure the number of Planck events in a gravitational mass without relying on any constants. This directly relates to a new and simple method for quantizing general relativity theory that we also will shortly discuss. 展开更多
关键词 planck Time Fundamental Time Indivisible Time NEWTON planck Length Quantum Gravity
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The Planck Constant and Its Relation to the Compton Frequency
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2024年第1期168-180,共13页
The Planck constant is considered one of the most important universal constants of physics, and despite all we know much about it, the physical nature of it has not been fully understood. Further investigation and new... The Planck constant is considered one of the most important universal constants of physics, and despite all we know much about it, the physical nature of it has not been fully understood. Further investigation and new perspectives on the Planck constant should therefore be of interest. We demonstrate that the Planck constant also can be directly linked to the Compton frequency of one, which again is divided by the Compton frequency in one kg. If this is right, it means also the Planck constant is linked to quantization of matter, not only energy. However, as we will show the frequency of one when expressed in relation to kg will be observational time dependent. This means the missing mass gap surprisingly both is equal to the Planck mass, which is larger than any known particle and also it is linked to a very small mass that again is equal to what has been suggested as the photon mass in the existing literature. This new view could be an important step forward in understanding the physical nature of the Planck constant as well as the mass gap and even the rest mass of a photon. 展开更多
关键词 planck Constant Compton Frequency ELECTRON Proton Count
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Planck Quantised General Relativity Theory Written on Different Forms
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2024年第6期2281-2301,共21页
This paper is a brief review of our work on the Planck quantized version of general relativity theory. It demonstrates several straightforward methods to rewrite the same equations that we have already presented in ot... This paper is a brief review of our work on the Planck quantized version of general relativity theory. It demonstrates several straightforward methods to rewrite the same equations that we have already presented in other papers. We also explore a relatively new general relativity-inspired field equation based on the original Newtonian mass, which is very different from today’s kilogram mass. Additionally, we examine two other field equations based on collision space-time, where both energy and matter can be described simply as space and time. We are thereby fulfilling Einstein’s dream of a theory where energy and mass are not needed, or are just aspects of space and time. If this is extended beyond the 4-dimensional space-time formalism of general relativity theory to a 6-dimensional framework with 3 space dimensions and 3 time dimensions, this ultimately reveals that they are two sides of the same coin. In reality, it is a three-dimensional space-time theory, where space and time are just two sides of the same coin. 展开更多
关键词 General Relativity planck Quantization Compton Frequency Composite Constant G Quantum Gravity Unification Collision Space-Time
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Upsilon Constants and Their Usefulness in Planck Scale Quantum Cosmology
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期167-173,共7页
This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper su... This paper introduces the two Upsilon constants to the reader. Their usefulness is described with respect to acting as coupling constants between the CMB temperature and the Hubble constant. In addition, this paper summarizes the current state of quantum cosmology with respect to the Flat Space Cosmology (FSC) model. Although the FSC quantum cosmology formulae were published in 2018, they are only rearrangements and substitutions of the other assumptions into the original FSC Hubble temperature formula. In a real sense, this temperature formula was the first quantum cosmology formula developed since Hawking’s black hole temperature formula. A recent development in the last month proves that the FSC Hubble temperature formula can be derived from the Stephan-Boltzmann law. Thus, this Hubble temperature formula effectively unites some quantum developments with the general relativity model inherent in FSC. More progress towards unification in the near-future is expected. 展开更多
关键词 Quantum Cosmology Hubble Constant planck Scale Upsilon Constant Flat Space Cosmology Black Holes CMB Temperature ΛCDM Cosmology Quantum Gravity Unification
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Fokker-Planck方程有限解析/Monte Carlo数值模拟方法 被引量:4
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作者 徐江荣 周俊虎 +1 位作者 张平 岑可法 《力学学报》 EI CSCD 北大核心 2006年第1期73-78,共6页
对白噪声驱动随机系统的Fokker-Planck方程进行约化,求得约化方程的解析解,使用局部解析解和 Monte Carlo结合方法求解常系数Fokker-Planck方程,并与常系数Eokker-Planck方程的精确解进行对比, 之后求解了变驱动力系统的行为.数值模拟... 对白噪声驱动随机系统的Fokker-Planck方程进行约化,求得约化方程的解析解,使用局部解析解和 Monte Carlo结合方法求解常系数Fokker-Planck方程,并与常系数Eokker-Planck方程的精确解进行对比, 之后求解了变驱动力系统的行为.数值模拟结果表明,有限解析/Monte Carlo结合的方法,能成功求解-维 Fokker-Planck方程,求解粒子数为105个,能获得十分光滑的PDF分布曲线,计算颗粒在300个时,就能获得较好的均值.其研究为两相湍流PDF模型新计算方法研究提供基础. 展开更多
关键词 fokker-planck方程 MONTE CARLO方法 数值计算 两相流动
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基于Fokker-Planck方程的电介质材料短脉冲激光破坏机制分析 被引量:8
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作者 陈发良 李东海 《强激光与粒子束》 EI CAS CSCD 北大核心 2011年第2期334-338,共5页
基于Pokker-Planck方程,建立一个描述短脉冲激光作用下电介质材料中导带电子能量分布随时间变化的模型,用数值方法计算电子能量分布与电子数密度随时间的演化过程,根据临界等离子体密度准则得到了不同激光脉冲宽度和波长下电介质材料(以... 基于Pokker-Planck方程,建立一个描述短脉冲激光作用下电介质材料中导带电子能量分布随时间变化的模型,用数值方法计算电子能量分布与电子数密度随时间的演化过程,根据临界等离子体密度准则得到了不同激光脉冲宽度和波长下电介质材料(以SiO2为例)的破坏阈值。结果发现,尽管激光波长通过3种途径对材料破坏阈值的确定产生影响,但三者的共同作用导致在激光波长分别为1 060,800,532 nm时材料破坏阈值随脉宽变化曲线十分接近。讨论了碰撞电离、光致电离两种机制对材料激光破坏分别所起的作用:当激光脉宽大于1 ps时,碰撞电离对材料的破坏起主要作用;当激光脉宽小于1 ps时,光致电离对破坏阈值的影响越来越明显,但是碰撞电离仍然不可忽略,碰撞电离与光致电离同时起重要作用。 展开更多
关键词 短脉冲激光 fokker-planck方程 碰撞电离 光致电离 破坏阈值
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电子束能量沉积的相对论Fokker-Planck方程的计算方法 被引量:3
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作者 张华 吴思忠 +5 位作者 周沧涛 何民卿 蔡洪波 曹莉华 朱少平 贺贤土 《计算物理》 CSCD 北大核心 2017年第5期555-562,共8页
针对相对论电子束在高密度等离子体中的能量沉积过程,建立三维动量空间中快电子能量沉积的相对论Fokker-Planck方程的可计算物理模型,构造数值算法并研制数值模拟程序.通过与解析模型和蒙特卡罗模拟相比较,验证数值方法和程序的可靠性.... 针对相对论电子束在高密度等离子体中的能量沉积过程,建立三维动量空间中快电子能量沉积的相对论Fokker-Planck方程的可计算物理模型,构造数值算法并研制数值模拟程序.通过与解析模型和蒙特卡罗模拟相比较,验证数值方法和程序的可靠性.在二维动量空间的模拟基础上,通过计算能量区间为0.5 MeV^3.5 MeV的快电子在背景密度为300 g·cm^(-3)的氘氚等离子体中的能量沉积过程,发现由于碰撞效应使平均散射角趋近平衡,三维动量空间计算快电子连续射程和穿透深度与二维结果基本一致. 展开更多
关键词 电子束 能量沉积 相对论fokker-planck方程
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Fokker—Planck方程 被引量:3
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作者 邵耀椿 封国林 李俊来 《昆明理工大学学报(自然科学版)》 CAS 1996年第S1期18-21,共4页
介绍了近几年朗之万方程和Fokker-Planck方程在各学科中的应用,特别指出了在生物遗传学、气象学中的最近研究动态;扼要概括了Fokker-Planck方程的研究方法,强调了矩阵连分法的应用前景.
关键词 fokker-planck方程 矩阵连分法 朗之万方程 非线性
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冷等离子体中的Fokker-Planck方程 被引量:1
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作者 杜凯 宋国利 +2 位作者 谭凯 杨幼桐 李明远 《黑龙江大学自然科学学报》 CAS 2002年第4期78-81,共4页
冷等离子体高的活性,可以引起多种化学反应或物理掺杂,对于低温下材料表面的改性有着较大优势。讨论了描写冷等离子体输运过程的Fokker-Planck方程,同时提出了目前Fokker-Planck方程描写存在的困难以及解决的可能途径。
关键词 冷等离子体 fokker-planck方程 表面改性 输运过程 分布函数
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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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Fokker-Planck方程的守恒量 被引量:1
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作者 秦茂昌 梅凤翔 许学军 《动力学与控制学报》 2005年第1期7-9,共3页
利用系统运动方程的线性化方程及其伴随方程的相互关系,以及散度表达式在全Euler算子作用下为零这一特性,通过引进守恒量乘子来求得运动系统的守恒量.该方法不需要运动系统的Lagrange函数.以Fokker-Planck方程为例,利用该方法可以很容... 利用系统运动方程的线性化方程及其伴随方程的相互关系,以及散度表达式在全Euler算子作用下为零这一特性,通过引进守恒量乘子来求得运动系统的守恒量.该方法不需要运动系统的Lagrange函数.以Fokker-Planck方程为例,利用该方法可以很容易给出它的无穷多守恒量. 展开更多
关键词 fokker-planck方程 守恒量 LAGRANGE函数 运动系统 线性化方程 EULER 相互关系 伴随方程 运动方程 利用系统 表达式 无穷多 算子 乘子
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基于三维Fokker-Planck方程的电子回旋波加热与电流驱动模拟 被引量:1
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作者 郑平卫 何丽华 +2 位作者 黄千红 邓盛 龚学余 《计算物理》 CSCD 北大核心 2017年第4期387-393,共7页
利用反弹平均的三维Fokker-Planck方程,对电子回旋波加热和电流驱动进行数值模拟.考虑超热电子径向扩散对电流驱动的影响,在方程中加入径向扩散输运项,采用九点格式的中心差分对方程进行数值离散得到系数矩阵,采用不完全LU分解对系数矩... 利用反弹平均的三维Fokker-Planck方程,对电子回旋波加热和电流驱动进行数值模拟.考虑超热电子径向扩散对电流驱动的影响,在方程中加入径向扩散输运项,采用九点格式的中心差分对方程进行数值离散得到系数矩阵,采用不完全LU分解对系数矩阵进行预处理,利用双共轭梯度稳定法求解得到分布函数.在不考虑电子径向扩散输运条件下,得到电子回旋波驱动电流密度与功率沉积密度的分布;考虑径向扩散输运的计算结果与BANDIT3D进行比较,驱动电流分布的趋势基本一致. 展开更多
关键词 fokker-planck方程 分布函数 电子回旋波 加热与电流驱动
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Fokker-Planck方程的非古典势对称群及新显式解 被引量:2
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作者 秦茂昌 梅凤翔 《动力学与控制学报》 2006年第2期103-108,共6页
本文利用一种新方法对Fokker- Planck方程的非古典势对称群生成元进行研究,找到方程的几个非古典势对称群生成元,并采用非古典对称群方法由这些对称群生成元构造得到Fokker- Planck方程的相应显式解.这些新显式解不能由Fokker -Planck... 本文利用一种新方法对Fokker- Planck方程的非古典势对称群生成元进行研究,找到方程的几个非古典势对称群生成元,并采用非古典对称群方法由这些对称群生成元构造得到Fokker- Planck方程的相应显式解.这些新显式解不能由Fokker -Planck方程本身的Lie对称或Li-e B cklund对称来获得.在验证所求得显式解的过程中,还发现并得到了另外几个显式解.这些新显式解则不能由Fokker -Planck方程本身的Lie对称,Lie- B cklund对称或非古典势对称来获得.文章表明,通过偏微分方程的非古典势对称群生成元来寻找其显式解是可能的. 展开更多
关键词 非古典势对称群 显式解 fokker-planck方程
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一维Fokker-Planck方程Milstein方法的收敛性 被引量:1
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作者 王文强 易锋 《湘潭大学自然科学学报》 CAS CSCD 北大核心 2009年第1期1-4,共4页
针对白噪声驱动随机系统的一维Fokker-Planck方程,得到了带线性插值的Milstein方法在均方意义下是收敛的理论结果.
关键词 fokker-planck方程 MILSTEIN方法 插值 收敛性
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用二维含时Fokker-Planck方程分析Tokamak中α粒子的输运 被引量:1
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作者 王少杰 邱励俭 《计算物理》 CSCD 北大核心 1996年第2期129-135,共7页
按分布函数的定义不同,描述高能带电粒子在等离子体中输运的 Fokker-Planck 方程有不同的形式。从数值计算的观点出发对两种不同形式的 Fokker-Planck 方程作了比较和评价,并指出Fokker-Planck 碰撞项可解释为速度空间的对流扩散项。在... 按分布函数的定义不同,描述高能带电粒子在等离子体中输运的 Fokker-Planck 方程有不同的形式。从数值计算的观点出发对两种不同形式的 Fokker-Planck 方程作了比较和评价,并指出Fokker-Planck 碰撞项可解释为速度空间的对流扩散项。在此基础上用有限差分方法求解二维(速度一维,几何一维)含时 Fokker-Planck 方程,编制了计算程序 CAPT,并将其应用于α粒子的输运研究。最后计算了典型的 Tokamak D-T 聚变堆参数下α粒子的损失,并给出了堆内α粒子的分布及损失α粒子的速度分布。 展开更多
关键词 Α粒子 等离子体 输运 托卡马克
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非线性Fokker-Planck方程的Hermite谱配置方法 被引量:1
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作者 王天军 杨森 《安徽工业大学学报(自然科学版)》 CAS 2012年第4期381-384,共4页
以Hermite-Gauss节点为配置点,用谱配置方法求数值解,逼近无界区域上的非线性Fokker-Planck方程初值问题的理论解。给出算法格式,数值运算表明所提算法格式的有效性和高精度。所给算法尤其适合于非线性问题,也可用于求解无界区域上非线... 以Hermite-Gauss节点为配置点,用谱配置方法求数值解,逼近无界区域上的非线性Fokker-Planck方程初值问题的理论解。给出算法格式,数值运算表明所提算法格式的有效性和高精度。所给算法尤其适合于非线性问题,也可用于求解无界区域上非线性常微分方程定解问题。 展开更多
关键词 非线性fokker-planck方程 初值问题 谱配置方法 Hermite-Gauss节点
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