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Gravitation, Density Upper Limit and Quantization of Space
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期534-545,共12页
The singularity at distance r → 0 at the center of a spherically symmetric non-rotating, uncharged mass of radius R, is considered here. Under inverse square law force, the Schwarzschild metric, needs to be modified,... The singularity at distance r → 0 at the center of a spherically symmetric non-rotating, uncharged mass of radius R, is considered here. Under inverse square law force, the Schwarzschild metric, needs to be modified, to include Newton’s Shell Theorem (NST). By including NST for r, both Schwarzschild singularity at r = 2GM/c2 and at r → 0 singularities are removed from the metric. Near R → 0, the question of maximal density is considered based on Schwarzschild’s modified metric, and compared to the quantum limit of maximal mass density put by Planck’s quantum-based universal units. It is asserted, that General relativity, when combined with Planck’s universal units, inevitably leads to quantization of gravity. 展开更多
关键词 GRAVITATION shell theorem SINGULARITY Schwarzschild Radius CGH Physics: Planck’s Scale
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTROSTATIC Electron POSITRON COULOMB Force ATTRACTION REPULSION Wave Function Electric Magnetic Radiation Pressure shell theorem 3D Computer Model Quantum
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS Klein GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow ATTRACTION REPULSION shell theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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ELXED POINT THEOREM OF COMPOSITION g-CONTRACTION MAPPING AND ITS APPLICATIONS 被引量:1
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作者 YUN Tian-quan(云天铨) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1132-1139,共8页
Any composition sequential mapping, periodic composition mapping of a complete non-empty metric space M into M with geometric mean contraction ratio less than 1 ( simplifying as 'g-contraction mapping' ) has a... Any composition sequential mapping, periodic composition mapping of a complete non-empty metric space M into M with geometric mean contraction ratio less than 1 ( simplifying as 'g-contraction mapping' ) has a unique fixed point in M . Applications of the theorem to the proof of existence and uniqueness of the solutions of a set of non-linear differential equations and a coupled integral equations of symmetric bending of shallow shell of revolution are given. 展开更多
关键词 CONTRACTION MAPPING g-contraction MAPPING BANACH CONTRACTION MAPPING theorem functional analysis differential EQUATION integral EQUATION SHALLOW shell
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Neumann's method for boundary problems of thin elastic shells
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作者 Y. S. NEUSTADT 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第4期543-556,共14页
The possibility of using Neumann's method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the... The possibility of using Neumann's method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the distribution space. The convergence of Neumann's method is proven for the shells with holes when the boundary of the domain is not completely fixed. The numerical implementation of Neumann's method normally requires significant time before any reliable results can be achieved. This paper suggests a way to improve the convergence of the process, and allows for parallel computing and evaluation during the calculations. 展开更多
关键词 boundary problem thin elastic shell theory Neumann's method variational principle Korn's inequality distribution embedding theorem Green tensor
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有限浸没深度无限长圆柱壳辐射声场波动特性 被引量:9
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作者 李天匀 江丰 +1 位作者 叶文兵 朱翔 《中国舰船研究》 2013年第1期73-79,共7页
研究水下圆柱壳声辐射问题时常常将流体声介质假设为无限域,而在实际工程中流体为存在自由液面的有限域。针对此假设的不足,基于Flügge薄壳振动方程和Helmholtz方程,利用镜像法和汉克尔函数的加法定理建立自由液面以下有限浸没深... 研究水下圆柱壳声辐射问题时常常将流体声介质假设为无限域,而在实际工程中流体为存在自由液面的有限域。针对此假设的不足,基于Flügge薄壳振动方程和Helmholtz方程,利用镜像法和汉克尔函数的加法定理建立自由液面以下有限浸没深度处圆柱壳结构与声场的耦合振动方程,研究辐射声场中辐射声压随浸没深度的波动特性。研究表明,不同频率下远场辐射声压随浸没深度的变化曲线上,波峰之间的距离为流体声波波长的1/2。研究结论可为实际工程应用提供理论基础。 展开更多
关键词 自由液面 圆柱壳 远场辐射声压 镜像法 加法定理
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考虑流体静压时充液圆柱壳的输入能量流特性 被引量:2
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作者 刘志忠 李天匀 张俊杰 《中国舰船研究》 2009年第2期20-23,共4页
研究了内部流体静压力对充液圆柱壳的受迫振动能量流的影响。静压力作为预应力计入壳体振动方程当中,壳体和流体分别采用Flügge方程和Helmholtz波动方程。分析了耦合系统在周向线分布余弦载荷下的动态响应,用傅立叶变换和反变换实... 研究了内部流体静压力对充液圆柱壳的受迫振动能量流的影响。静压力作为预应力计入壳体振动方程当中,壳体和流体分别采用Flügge方程和Helmholtz波动方程。分析了耦合系统在周向线分布余弦载荷下的动态响应,用傅立叶变换和反变换实现空间域与波数域之间的相互转换,采用留数定理求取系统的响应并得到耦合系统的输入能量流。结果表明,周向模态数n=0时,静压力对耦合系统的输入能量流影响很小;n较大时,在中低频下静压力使输入能量流曲线沿频率轴右移,由于输入能量流的峰值点处的频率对应于频散曲线中各支传播波的截止频率,对应传播波的截止频率升高,高频时则基本无影响。随着静压力以及周向模态数的增大,输入能量流受到的影响程度也增大。 展开更多
关键词 充液圆柱壳 输入能量流 静压力 留数定理
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引力场和静电场中几个重要定理的严格数学证明
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作者 沈进中 邓留保 《上饶师范学院学报》 2017年第3期58-64,共7页
物理学是理解各类实际模型的基础,深刻理解物理中的重要定理十分重要。从基本定义出发,采用多元积分的方法给出文献[1]中球壳定理的严格数学证明。进一步考虑均匀实心球体和两类带空腔球体的万有引力场分布,给出对应的严格数学证明。根... 物理学是理解各类实际模型的基础,深刻理解物理中的重要定理十分重要。从基本定义出发,采用多元积分的方法给出文献[1]中球壳定理的严格数学证明。进一步考虑均匀实心球体和两类带空腔球体的万有引力场分布,给出对应的严格数学证明。根据引力场与静电场的表达形式的相似之处,给出均匀带电球壳、实心球体和两类带空腔球体电场分布的数学表达式。 展开更多
关键词 球壳定理 引力场 第二类曲面积分 静电场
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高动态金属壳谐振陀螺进动特性分析 被引量:1
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作者 刘宁 邓志红 《导航定位与授时》 2017年第2期86-92,共7页
高动态金属壳谐振陀螺的进动特性,是敏感结构实现角速率信息有效提取的关键。针对金属壳谐振陀螺的进动特性进行研究,首先分析了金属壳谐振陀螺的总体研究思路,明确其工作原理;建立敏感结构的动力学方程和进动因子表达式;利用数值分析方... 高动态金属壳谐振陀螺的进动特性,是敏感结构实现角速率信息有效提取的关键。针对金属壳谐振陀螺的进动特性进行研究,首先分析了金属壳谐振陀螺的总体研究思路,明确其工作原理;建立敏感结构的动力学方程和进动因子表达式;利用数值分析方法,对进动因子进行分析,得出金属壳谐振陀螺进动因子经验公式;最后对其进动特性进行综合分析。 展开更多
关键词 高动态金属壳谐振陀螺 敏感结构 哥氏定理
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Gravitation, Density, Black Holes and Spatial Quantization
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2022年第4期990-1011,共22页
Making use of Newton’s classical shell theorem, the Schwarzschild metric is modified. This removes the singularity at r = 0 for a standard object (not a black hole). It is demonstrated how general relativity evidentl... Making use of Newton’s classical shell theorem, the Schwarzschild metric is modified. This removes the singularity at r = 0 for a standard object (not a black hole). It is demonstrated how general relativity evidently leads to quantization of space-time. Both classical and quantum mechanical limits on density give the same result. Based on Planck’s length and the assumption that density must have an upper limit, we conclude that the lower limit of the classical gravitation theory by Einstein is related to the Planck length, which is a quantum phenomenon posed by dimensional analysis of the universal constants. The Ricci tensor is considered under extreme densities (where Kretschmann invariant = 0) and a solution is considered for both outside and inside the object. Therefore, classical relativity and the relationship between the universal constants lead to quantization of space. A gedanken experiment of light passing through an extremely dense object is considered, which will allow for evaluation of the theory. 展开更多
关键词 Newton’s shell theorem Schwarzschild Singularities Photon Sphere Planck’s Units Quantization of Space
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壳体结构非线性分析的扁壳有限元法 被引量:1
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作者 王荣辉 曾庆元 《固体力学学报》 CAS CSCD 北大核心 1999年第3期259-266,共8页
用单位纵横向曲条条带法构造了扁壳单元的空间位移模式,依据拖带坐标描述法和S-R分解定理,导出了扁壳结构几何非线性分析的有限单元U.C.(updatedco-movingcordinate)列式.算例表明,该计算方法精度高,收敛性好.
关键词 纵横向曲条条带 扁壳单元 壳体结构 有限元
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旋转封闭薄壁球壳辐射噪声的多极展开方法 被引量:1
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作者 侯明明 吴九汇 姜宁 《西安交通大学学报》 EI CAS CSCD 北大核心 2014年第7期102-108,共7页
针对旋转机械噪声问题,在旋转单极子声源和偶极子声源辐射声场频域解的基础上,基于这两种简单旋转声源的研究思路和方法,利用声学互易定理推导出了简单封闭薄壁球壳作旋转运动时的空间辐射声场的计算方法,以一具体的封闭薄壁球壳为对象... 针对旋转机械噪声问题,在旋转单极子声源和偶极子声源辐射声场频域解的基础上,基于这两种简单旋转声源的研究思路和方法,利用声学互易定理推导出了简单封闭薄壁球壳作旋转运动时的空间辐射声场的计算方法,以一具体的封闭薄壁球壳为对象对旋转运动进行了实例计算。在此基础上,利用覆盖域的思想,给出了一种可以计算任意复杂形状封闭薄壳在旋转运动时空间辐射声场的方法。所提方法可为研究气动噪声产生机理及定量分析提供可借鉴的思路,为旋转机械噪声的控制及优化提供了一种方法。 展开更多
关键词 旋转机械噪声 声学互易原理 覆盖域方法 旋转封闭薄壁球壳 辐射声场
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复合g-收缩映射不动点定理及其应用 被引量:1
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作者 云天铨 《应用数学和力学》 CSCD 北大核心 2001年第10期1022-1028,共7页
任一几何平均收缩比率小于 1(简称g_收缩映射 )的由完备的非空度量空间 M到M的复合序列映射 ,复合周期映射有在M中的唯一的不动点 · 文中给出定理应用于一组非线性微分方程以及扁壳轴对称弯曲的耦合的积分方程的解的存在和唯一性... 任一几何平均收缩比率小于 1(简称g_收缩映射 )的由完备的非空度量空间 M到M的复合序列映射 ,复合周期映射有在M中的唯一的不动点 · 文中给出定理应用于一组非线性微分方程以及扁壳轴对称弯曲的耦合的积分方程的解的存在和唯一性证明的应用例子· 展开更多
关键词 收缩映射 g-收缩映射 Banach收缩映射定理 泛函关系 迭代法 微分方程 积分方程 不动点定理
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均匀带电球面电场强度的再讨论 被引量:4
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作者 牛庆林 王晓丽 《临沂大学学报》 2016年第1期142-144,共3页
通过求带电球壳内电场强度在内外半径趋于相同时的极限,计算了均匀带电球面上的电场强度,与利用叠加原理或虚功原理计算的结果完全相同.并对均匀带电球面上的电场强度的不连续性进行了探讨,发现这种不连续来源于将带电球壳理想化为无限... 通过求带电球壳内电场强度在内外半径趋于相同时的极限,计算了均匀带电球面上的电场强度,与利用叠加原理或虚功原理计算的结果完全相同.并对均匀带电球面上的电场强度的不连续性进行了探讨,发现这种不连续来源于将带电球壳理想化为无限薄球面的过程. 展开更多
关键词 均匀带电球面 电场强度 均匀带电球壳 叠加原理 高斯定理
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基于Backstepping方法的MIMO过程分散PID控制器设计 被引量:3
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作者 张艳 李少远 《自动化学报》 EI CSCD 北大核心 2005年第5期675-682,共8页
A novel decentralized PID controller design procedure based on backstepping principles is presented to operate multiple-input multiple-output (MIMO)dynamic processes. The first key feature of the design procedure is t... A novel decentralized PID controller design procedure based on backstepping principles is presented to operate multiple-input multiple-output (MIMO)dynamic processes. The first key feature of the design procedure is that a whole MIMO control system is decomposed into multiple control loops, therefore the sub-controllers can be efficiently flexibly designed in parallel prototype.The second key feature is that the decentralized controller has equivalency to those designed by backstepping approach. As a complementary support to the design procedure, the sufficient condition of the whole closed-loop system stability is analyzed via the small gain theorem and it can be proven that the process tracking performance is improved. The simulation results of the Shell benchmark control problem are provided to verify the effectiveness and practicality of the proposed decentralized PID control. 展开更多
关键词 MIMO 过程分散 PID控制器 动态过程 控制环
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正交异性层合圆柱厚壳静、动态问题的分析解
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作者 范家让 《合肥工业大学学报(自然科学版)》 CAS CSCD 1990年第1期20-30,共11页
本文抛弃任何有关位移或应力模式的假设,在柱坐标系下对圆柱型正交异性体建立其状态方程。对层合圆柱厚壳利用Cayley-Hamilton定理一次求解全部未知量。无论层数多少,最后都归结为求解三元一次代数方程组。此解满足所有弹性力学方程并... 本文抛弃任何有关位移或应力模式的假设,在柱坐标系下对圆柱型正交异性体建立其状态方程。对层合圆柱厚壳利用Cayley-Hamilton定理一次求解全部未知量。无论层数多少,最后都归结为求解三元一次代数方程组。此解满足所有弹性力学方程并计及了全部弹性常数,可得到任意需要的精度。 展开更多
关键词 正交异性体 弹性力学 层合圆柱厚壳
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旋转体体积计算方法的探讨
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作者 孟献青 《山西大同大学学报(自然科学版)》 2022年第4期27-29,共3页
旋转体的体积是高等数学的重要考核内容,具有较强的应用性。文章研究了平面图形绕坐标轴及任意直线旋转所得旋转体的体积。如果平面图形具有对称性,则可利用Pappus定理简化计算过程。通过一题多解思想,拓宽学生思路,强化知识之间的联系... 旋转体的体积是高等数学的重要考核内容,具有较强的应用性。文章研究了平面图形绕坐标轴及任意直线旋转所得旋转体的体积。如果平面图形具有对称性,则可利用Pappus定理简化计算过程。通过一题多解思想,拓宽学生思路,强化知识之间的联系,形成结实的知识网。 展开更多
关键词 旋转体 形心 柱壳法 PAPPUS定理
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不同模量壳体理论广义弹性定律的普遍表达式
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作者 汤震 《应用力学学报》 CAS CSCD 北大核心 1991年第4期82-84,136,共3页
本文研究了拉伸和压缩不同模量材料制成的壳体弱矩理论的本构关系,导出了广义弹性定律的普遍表达式,即中曲面法向坐标的各任意幂次项系数的公式,并指出文献[1]中最终公式保留的线性项,仅为本文普遍表达式的一个较简单的特殊情形,因此,... 本文研究了拉伸和压缩不同模量材料制成的壳体弱矩理论的本构关系,导出了广义弹性定律的普遍表达式,即中曲面法向坐标的各任意幂次项系数的公式,并指出文献[1]中最终公式保留的线性项,仅为本文普遍表达式的一个较简单的特殊情形,因此,可以不顾文献[1]中关于应力沿壳厚按线性规律变化的基本假设。 展开更多
关键词 模量 壳体弱矩理论 广义 弹性定律
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圆形底边球面网壳的简化计算法
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作者 孙绍文 《吉林建筑工程学院学报》 CAS 1994年第2期12-20,共9页
笔者在查阅、推敲对比国内外有关壳体内力计算资料的基础上,向读者推出了求解圆形底边球面网壳杆件内力的简化计算方法,给出了该网壳在自重、雪、风荷载作用下的内力计算公式.按此法求得的内力值可直接用干设计薄壳,又可以换算成网壳的... 笔者在查阅、推敲对比国内外有关壳体内力计算资料的基础上,向读者推出了求解圆形底边球面网壳杆件内力的简化计算方法,给出了该网壳在自重、雪、风荷载作用下的内力计算公式.按此法求得的内力值可直接用干设计薄壳,又可以换算成网壳的杆件轴力进行网壳设计.只要边界条件满足本文要求,此法可直接用于工程设计,既有利于壳体结构的推广,又大大减轻设计人员的计算工作量. 展开更多
关键词 圆形底边球形网壳 径向力 环向力 薄壳理论 有矩理论 边界效应
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叠层双曲率厚壳静、动态问题的分析解
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作者 范家让 张巨勇 《合肥工业大学学报(自然科学版)》 CAS CSCD 1990年第4期1-15,共15页
本文抛弃任何有关位移或应力分布的假设,在正交曲线坐标系下,对正交异性双曲率厚壳建立其状态方程。根据层问应力和位移协调条件,对具有正交异性层的周边简支的层合双曲丰厚壳的静力和动力问题,利用Cayley-Hamilton定理一次求解全部未... 本文抛弃任何有关位移或应力分布的假设,在正交曲线坐标系下,对正交异性双曲率厚壳建立其状态方程。根据层问应力和位移协调条件,对具有正交异性层的周边简支的层合双曲丰厚壳的静力和动力问题,利用Cayley-Hamilton定理一次求解全部未知量。无论层数多少,最后都归结为只需求解三元一次代数方程组。此解满足所有弹性力学基本方程,并计及了全部弹性常数。可得到任意需要的精度。数值结果与文献[3]及[6]作了对比,结论令人满意。 展开更多
关键词 CAYLEY-HAMILTON定理 代数方程组 弹性力学 正交异性层
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