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STRONG LAW OF LARGE NUMBERS AND SHANNON-MCMILLAN THEOREM FOR MARKOV CHAINS FIELD ON CAYLEY TREE 被引量:2
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作者 杨卫国 刘文 《Acta Mathematica Scientia》 SCIE CSCD 2001年第4期495-502,共8页
This paper studies the strong law of large numbers and the Shannom-McMillan theorem for Markov chains field on Cayley tree. The authors first prove the strong law of large number on the frequencies of states and order... This paper studies the strong law of large numbers and the Shannom-McMillan theorem for Markov chains field on Cayley tree. The authors first prove the strong law of large number on the frequencies of states and orderd couples of states for Markov chains field on Cayley tree. Then they prove the Shannon-McMillan theorem with a.e. convergence for Markov chains field on Cayley tree. In the proof, a new technique in the study the strong limit theorem in probability theory is applied. 展开更多
关键词 Cayley tree random field Markov chains field strong law of large numbers Shannon-McMillan theorem
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STRONG LAW OF LARGE NUMBERS AND ASYMPTOTIC EQUIPARTITION PROPERTY FOR NONSYMMETRIC MARKOV CHAIN FIELDS ON CAYLEY TREES 被引量:2
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作者 包振华 叶中行 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期829-837,共9页
Some strong laws of large numbers for the frequencies of occurrence of states and ordered couples of states for nonsymmetric Markov chain fields (NSMC) on Cayley trees are studied. In the proof, a new technique for ... Some strong laws of large numbers for the frequencies of occurrence of states and ordered couples of states for nonsymmetric Markov chain fields (NSMC) on Cayley trees are studied. In the proof, a new technique for the study of strong limit theorems of Markov chains is extended to the case of Markov chain fields, The asymptotic equipartition properties with almost everywhere (a,e.) convergence for NSMC on Cayley trees are obtained, 展开更多
关键词 Cayley tree nonsymmetric Markov chain fields strong law of large numbers asymptotic equipartition property
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CONVERGENCE RATES IN THE STRONG LAWS OF NONSTATIONARYρ~*-MIXING RANDOM FIELDS 被引量:8
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作者 张立新 《Acta Mathematica Scientia》 SCIE CSCD 2000年第3期303-312,共10页
By using a Rosenthal type inequality established in this paper, the complete convergence and almost sure summability on the convergence rates with respect to the strong law of large numbers are discussed for *-mixing... By using a Rosenthal type inequality established in this paper, the complete convergence and almost sure summability on the convergence rates with respect to the strong law of large numbers are discussed for *-mixing random fields. 展开更多
关键词 Rosenthal type inequality strong law of large numbers *-mixing random fields
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The Basic Concepts and Basic Laws Relating to Matter and Gravitational Fields in Physics
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作者 Fangpei Chen 《Journal of Modern Physics》 2017年第11期1784-1794,共11页
In this work, the author applied the universal gauge field theory and Noether theorem to prove that universality exists for the Lorentz and Levi-Civita law of conservation of energy momentum tensor density. We also fo... In this work, the author applied the universal gauge field theory and Noether theorem to prove that universality exists for the Lorentz and Levi-Civita law of conservation of energy momentum tensor density. We also found that this conservation law has profound implications in physics. For example, based on this law, one can explore the origin of the matter field, and propose a new view about what is “dark energy” and what is “dark matter”. 展开更多
关键词 LAGRANGIAN MATTER field GRAVITATIONAL field ENERGY-MOMENTUM TENSOR Density Conservation law Origin of MATTER field
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The Natural Law of Transition of a Charged Particle into a Compound State under the Action of an Electroscalar Field
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作者 Oleg Antonovich Zaimidoroga 《Journal of Modern Physics》 2016年第15期2188-2204,共17页
This article is the continuation of article [1] where the experimental facts of observation of the electroscalar radiation in the spectrum of the Sun have been presented [2]. This radiation comes into the world having... This article is the continuation of article [1] where the experimental facts of observation of the electroscalar radiation in the spectrum of the Sun have been presented [2]. This radiation comes into the world having a long wavelength, being longitudinal and extraordinarily penetrating. In accordance with the principle of least action, the Lagrangian of the electroscalar field and the tensor of energy-moment are determined using the variation the potential and coordinates. The equation of motion the charged particle in electroscalar field is determined and the energy of particle has the negative sign with respect to the mechanical energy of particle and the energy of electromagnetic field. So, this is decreasing the electrical potential of particle during the propagation. The electroscalar energy of charged particle and field’s force acting on the particle during their motion change the particle’s electrical status which, in its turn, may trigger the transition of the particle into a compound state during interaction with any object. Due to the continuity this process can lead the particle to the state which enters into a compound state with a negative energy for a different particle’s velocity. This state is the physical vacuum’s state. Analysis of the solar spectrum demonstrates that scattering and absorption of electroscalar wave go on the cavities of solids. The spreading out of electroscalar field obeys to the law of plane wave and the transfer the energy and information can occur in vacuum and any medium. 展开更多
关键词 Equation of Motion of Electroscalar field Tensor Energy-Moment of Electroscalar field Natural law of Particle’s Transition into a Compound State Physical Vacuum
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New approach for obtaining the time-evolution law of a chaotic light field in a damping gaining-process
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作者 龚黎华 周南润 +1 位作者 胡利云 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第8期31-33,共3页
A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(... A new approach for studying the time-evolution law of a chaotic light field in a damping-gaining coexisting process is presented. The new differential equation for determining the parameter of the density operator p(t) is derived and the solution of f for the damping and gaining processes are studied separately. Our approach is direct and the result is concise since it is not necessary for us to know the Kraus operators in advance. 展开更多
关键词 chaotic light field damping gaining process time evolution law quantum communication
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中国法治国际传播的主场外交途径研究
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作者 邢爱芬 颜鸽 《河南社会科学》 北大核心 2026年第2期78-86,共9页
中国法治的国际传播是全面依法治国战略布局的重要组成部分,有利于让世界看到更加真实、立体、全面的中国法治形象,形成同我国综合国力和国际地位相匹配的国际话语权。然而,长期以来“西强我弱”的国际传播格局和“西方中心主义”话语... 中国法治的国际传播是全面依法治国战略布局的重要组成部分,有利于让世界看到更加真实、立体、全面的中国法治形象,形成同我国综合国力和国际地位相匹配的国际话语权。然而,长期以来“西强我弱”的国际传播格局和“西方中心主义”话语体系严重阻碍了中国发声,加之数智赋能国际传播的负面效应溢出,致使中国法治的国际传播难以达到应有效果。新时代以来,中国主办了多次重大主场外交活动,为中国法治国际传播提供了崭新的重要平台。但同时,运用主场外交加强中国法治国际传播也存在主体协调、传播范围、叙事方式、追踪机制等方面的难题。未来需要聚焦全球性议题,采用“跨文化共情”叙事方式讲好中国法治故事,健全成果落实机制以提升中国法治国际传播效能。 展开更多
关键词 主场外交 中国法治 国际传播 话语体系 涉外法治
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高功率微波对空间太阳电池阵的耦合效应
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作者 由俞宁 连汝慧 +4 位作者 曹柯涵 吴建超 宋法伦 宋佰鹏 张冠军 《强激光与粒子束》 北大核心 2026年第2期49-57,共9页
空间太阳电池阵作为航天器的重要能源组成部分,在未来对抗中极易受到以高功率微波为代表的外来强电磁脉冲侵袭。为研究空间太阳电池阵的高功率微波耦合效应,以典型太阳电池阵结构和布局作为参考,搭建了高功率微波辐照作用下的太阳电池... 空间太阳电池阵作为航天器的重要能源组成部分,在未来对抗中极易受到以高功率微波为代表的外来强电磁脉冲侵袭。为研究空间太阳电池阵的高功率微波耦合效应,以典型太阳电池阵结构和布局作为参考,搭建了高功率微波辐照作用下的太阳电池阵样品三维模型,研究了不同激励源参数条件(频率、极化方向、入射角度等)下的太阳电池阵耦合效应规律。结果表明:在2~18 GHz频率范围内,垂直极化的S波段微波辐照最容易对太阳电池阵造成诱发放电损伤,电池串间隙三结合部感应场强远高于互连片位置间隙;在微波辐照作用下太阳电池样品会感应出极强的瞬态电场,垂直极化情况下,感应场主要集中分布在电池串间隙、汇流条附近、电池片边缘;电池三结合部感应电场稳定峰值随微波入射角度的增大而减小,随微波功率密度的增大而增大;微波上升下降沿对感应电场值无明显影响;太阳电池阵串间隙周围空间的电场由间隙中心向外侧逐渐减小。该研究将为空间太阳电池阵的电磁防护设计提供参考。 展开更多
关键词 空间太阳电池阵 高功率微波 耦合瞬态场 影响规律 电磁防护
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Biquaternionic Model of Electro-Gravimagnetic Field, Charges and Currents. Law of Inertia
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作者 L. A. Alexeyeva 《Journal of Modern Physics》 2016年第5期435-444,共10页
One the base of Maxwell and Dirac equations the one biquaternionic model of electro-gravimagnetic (EGM) fields is considered. The closed system of biquaternionic wave equations is constructed for determination of free... One the base of Maxwell and Dirac equations the one biquaternionic model of electro-gravimagnetic (EGM) fields is considered. The closed system of biquaternionic wave equations is constructed for determination of free system of electric and gravimagnetic charges and currents and generated by them EGM-field. By using generalized functions theory the fundamental and regular solutions of this system are determined and some of them are considered (spinors, plane waves, shock EGM-waves and others). The properties of these solutions are investigated. 展开更多
关键词 Biquaternion Bigradient Biwave Equation Electro-Gravimagnetic field Electric Charge Gravimagnetic Charge Current Maxwell Equations First Newton law
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超声速冲击射流声场与流场特性及声源特征研究
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作者 齐龙舟 杨志刚 +2 位作者 吕镇东 刘翰林 卢鑫源 《推进技术》 北大核心 2026年第2期88-100,共13页
本研究聚焦于超声速冲击射流的噪声特性及声源分布,旨在明确其噪声生成机制及其与射流速度的n次方律关系。实验在全消声室内开展,采用高频PIV技术与远场传声器弧阵列结合,测量冲击射流的流场与声场分布。基于Ω准则和Q准则识别冲击射流... 本研究聚焦于超声速冲击射流的噪声特性及声源分布,旨在明确其噪声生成机制及其与射流速度的n次方律关系。实验在全消声室内开展,采用高频PIV技术与远场传声器弧阵列结合,测量冲击射流的流场与声场分布。基于Ω准则和Q准则识别冲击射流的涡量特征,分析涡量结构与离散纯音的关系。通过监测冲击射流下、中、上游方向监测角(β=30°,β=80°和β=120°)的总声压级(OASPL),研究了OASPL与射流速度之间的n次方律关系,并比较斯特劳哈尔数(St=0.61,St=0.33)的离散纯音随出口压比(NPR)和冲击距离(L/d)的变化趋势。去除离散纯音后,OASPL与射流速度的n次方律符合较好,不同监测角的速度因子分别为7.8(β=30°),7.0(β=80°)和10.8(β=120°),这反映了冲击射流噪声源特性随监测角变化的关系。进一步分析表明,OASPL、离散纯音幅值与射流速度梯度之间存在显著关联。通过Ω准则与Q准则对流场涡量进行识别,发现势流核第三至第五激波格栅后方的强涡量区域与啸叫声(Screech tone)主要声源位置吻合,实现了对声源的可视化定位。相位分析显示,NPR=2.37时,流场中涡对结构尺寸与St=0.33的离散纯音强度呈正相关,而NPR=2.84时,冲击射流顺流侧强涡量区尺寸与St=0.61的离散纯音强度呈正相关。本研究揭示了超声速冲击射流噪声总声压级与射流速度的幂次关系,并证实了不同监测角度和St条件下声源位置与强涡量区域的显著关联。通过对流场的Ω准则和Q准则涡量识别,确认了冲击射流势流核内主要声源区域与啸叫声的一致性,实现了声源的可视化定位。 展开更多
关键词 PIV流场 冲击射流 射流速度 n次方律 Ω准则
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RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CONTINUUM THEORIES (X) -MASTER BALANCE LAW 被引量:3
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第2期167-174,共8页
Through a comparison between the expressions of master balance laws and the conservation laws derived by Noether's theorem, a unified master balance law and six physically possible balance equations for micropolar co... Through a comparison between the expressions of master balance laws and the conservation laws derived by Noether's theorem, a unified master balance law and six physically possible balance equations for micropolar continuum mechanics are naturally deduced. Among them, by extending the well-known conventional concept of energymomentum tensor, the rather general conservation laws and balance equations named after energy-momentum, energy-angular momentum and energy-energy are obtained. It is clear that the forms of the physical field quantities in the master balance law for the last three cases could not be assumed directly by perceiving through the intuition. Finally, some existing results are reduced immediately as special cases. 展开更多
关键词 unified master balance law physical field quantities conservation laws ENERGY-MOMENTUM energy-angular momentum energy-energy
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多层复合采空区矿井密闭流场受自然风压影响研究
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作者 陈庆丰 张海洋 赵亚明 《煤炭技术》 2026年第1期152-155,共4页
在地表漏风及自然风压影响下,矿井密闭压差波动较大。为探明密闭内流场受自然风压影响程度,本文以屯宝煤矿为例,根据矿井通风理论,分析了自然风压对密闭的影响,提出了密闭内外漏风流向的判别方法,然后基于SF_(6)示踪气体测漏技术,测定... 在地表漏风及自然风压影响下,矿井密闭压差波动较大。为探明密闭内流场受自然风压影响程度,本文以屯宝煤矿为例,根据矿井通风理论,分析了自然风压对密闭的影响,提出了密闭内外漏风流向的判别方法,然后基于SF_(6)示踪气体测漏技术,测定了矿井密闭漏风量,最后依据密闭内气体浓度及巷道内的有害气体限值,明确了矿井密闭内外压差控制的安全范围。研究结果表明:屯宝煤矿采空区密闭内外安全压差为-200~200 Pa,矿井主通风机安全静压差为517~917 Pa,密闭内流场处于稳定状态,就不会发生采空区有害气体涌出现象。 展开更多
关键词 复合采空区 密闭流场 安全压差 漏风规律 自然风压
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Pulsed Magnetic Field Measurement Outside Finite Length Solenoid: Experimental Results &Mathematical Verification
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作者 Shibaji Basu Siddhartha Shankar Pany +1 位作者 Partha Bannerjee Sabyasachi Mitra 《Journal of Electromagnetic Analysis and Applications》 2013年第10期371-378,共8页
The paper deals with magnetic field mapping outside a finite length solenoid electromagnet, by an in-house designed and calibrated inductive pick-up or search coil. The search coil is calibrated in a unique methodolog... The paper deals with magnetic field mapping outside a finite length solenoid electromagnet, by an in-house designed and calibrated inductive pick-up or search coil. The search coil is calibrated in a unique methodology based on the azimuthal magnetic field component generated by a straight wire. This unique calibration technique helps us to avoid additional circuitry to integrate the signal obtained from search coil. The methodology proves advantageous in diffusion, implosion studies where the signal frequency changes with dimension and material of experimental job-piece (hollow metal tube). Remedial measures have been taken to avoid electrostatic capacitive pick-up (which eventually exacerbates with integration) keeping measurement simple and accurate. The experimentally measured field values have also been compared with electromagnetic field results obtained from mathematical calculations and finite element based simulations. Two different mathematical approaches have been demonstrated for field computation based on Biot-Savart Law. Both the methods have taken into account the exact geometry of the solenoid, including the inter-turn gaps. The methods use appropriate combination of closed-form mathematical expression and numerical integration techniques and are capable of determining all the vector components of magnetic field anywhere around the finite length solenoid. The mathematical computations are equally significant contributions in the paper especially because exact determination of magnetic fields outside finite length solenoids has not been discussed in sufficient specific details in already existing literature. The mathematical computations, finite element simulations and experimental verification together provide a holistic solution to magnetic field determination problems in pulse power applications that have not been discussed in available literature or books in specific details. 展开更多
关键词 PULSED Magnetic field Biot-Savart law Search COIL
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科技法的领域法定位与体系构建 被引量:1
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作者 万志前 王子洁 《科技与法律(中英文)》 2025年第1期14-25,共12页
科技法作为伴随科学技术发展产生的新兴学科,是我国法律体系的重要组成部分。面对复杂的科技法律现象和法律关系,以部门法思维定位科技法,存在逻辑难以自洽、无法适应社会发展及阻碍科技法研究与发展等问题。领域法作为回应新兴学科的... 科技法作为伴随科学技术发展产生的新兴学科,是我国法律体系的重要组成部分。面对复杂的科技法律现象和法律关系,以部门法思维定位科技法,存在逻辑难以自洽、无法适应社会发展及阻碍科技法研究与发展等问题。领域法作为回应新兴学科的研究范式,以问题导向性和开放性为基本特点。科技法契合了领域法的特点,将其定位为领域法,可有效回应科技发展中的领域性问题,突破部门法研究的隔离化,促进科技法的整体研究。完善领域法视域下科技法律的体系构建,应当明确其基本要求,确立《科技进步法》的基本法地位,健全科技领域的专门法,衔接好科技法律自身规范与其他领域科技法律规范的关系,保持两者之间的“分”与“合”的张力,由此形成科技法律体系内外协调的层次序列。同时,领域法并非否定传统部门法,包含科技法在内的领域法与传统部门法共同构成中国特色社会主义法律体系。 展开更多
关键词 领域法 部门法 科技法
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CONSTITUTIVE RELATION OF UNSATURATED SOIL BY USE OF THE MIXTURE THEORY (Ⅱ)—LINEAR CONSTITUTIVE EQUATIONS AND FIELD EQUATIONS
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作者 黄义 张引科 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第2期138-152,共15页
The linear constitutive equations and field equations of unsaturated soils were obtained through linearizing the nonlinear equations given in the first part of this work. The linear equations were expressed in the for... The linear constitutive equations and field equations of unsaturated soils were obtained through linearizing the nonlinear equations given in the first part of this work. The linear equations were expressed in the forms similar to Biot's equations for saturated porous media. The Darcy's laws of unsaturated soil were proved. It is shown that Biot's equations of saturated porous media are the simplification of the theory. All these illustrate that constructing constitutive relation of unsaturated soil on the base of mixture theory is rational. 展开更多
关键词 mixture theory unsaturated soil linear constitutive equation linear field equation Darcy's law Biot's equations
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A Unified Definition of Electrostatic and Magnetic Fields
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作者 Geoffroy Auvert 《Open Journal of Applied Sciences》 CAS 2023年第5期793-801,共9页
This article originates from the observation that field lines are drawn using distinctive rules in magnetic field and electrostatic fields. It aims at reconciliating the definitions of these fields and thus reaching a... This article originates from the observation that field lines are drawn using distinctive rules in magnetic field and electrostatic fields. It aims at reconciliating the definitions of these fields and thus reaching a consensus on the interpretation of field lines. Our unified field definition combines three orthogonal vectors and a unique scalar value. Field lines are then defined as isovalue lines of the scalar value, rendering it simpler to interpret in both field types. Specific to our field definition is the use of square root of vector’s cross product so that all vectors have the same physical unit. This enhanced field definition also enables a more efficient calculation of Biot-Savart law. This article is the first of a series allowing the drawing of isovalue contour lines. 展开更多
关键词 Magnetic field Electrostatic field Biot-Savart law Scalar field Value Equipotential Line Square Root Cross Product
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Time evolution of a squeezed chaotic field in an amplitude damping channel when used as a generating field for a squeezed number state 被引量:4
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作者 徐兴磊 李洪奇 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期106-109,共4页
We investigate how an optical squeezed chaotic field(SCF) evolves in an amplitude dissipation channel. We have used the integration within ordered product of operators technique to derive its evolution law. We also ... We investigate how an optical squeezed chaotic field(SCF) evolves in an amplitude dissipation channel. We have used the integration within ordered product of operators technique to derive its evolution law. We also show that the density operator of SCF can be viewed as a generating field of the squeezed number state. 展开更多
关键词 squeezed chaotic field amplitude damping channel squeezed number state evolution law
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法治领域改革论纲 被引量:10
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作者 黄文艺 《政治与法律》 北大核心 2025年第5期2-20,共19页
与法律改革、法制改革概念相比,法治领域改革概念更具时代蕴涵力、理论解释力、实践变革力。法治领域改革的总体目标是,完善中国特色社会主义法治体系、建设更高水平的社会主义法治国家,即法治运行体制更为健全、法治规范体系更加完备... 与法律改革、法制改革概念相比,法治领域改革概念更具时代蕴涵力、理论解释力、实践变革力。法治领域改革的总体目标是,完善中国特色社会主义法治体系、建设更高水平的社会主义法治国家,即法治运行体制更为健全、法治规范体系更加完备、法律公平正义更为坚实、人权法治保障更为充分、权力制约监督更加有力、服务经济发展能力明显增强、国际法治领导力和贡献力显著提升。法治领域改革是一项系统工程,包括法治机构职能体系、法治规范制定体制、法治实施体制、涉外法治体制、法治监督体制、法治保障制度、依规治党体系等方面的变革。法治领域改革是社会利益关系和国家权力结构的深刻调整,必须坚持党的统一领导、以人民为中心、从中国国情出发、遵循法治规律、在法治轨道上推进、系统谋划和布局。 展开更多
关键词 法律改革 法制改革 法治领域改革 法治体系 法治规范体系
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A Self-Stabilized Field Theory of Neutrinos 被引量:3
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作者 Edwin Eugene Klingman 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期936-948,共13页
In “<i>A Self-linking Field Formalism</i>” I establish a self-dual field structure with higher order self-induced symmetries that reinforce the first-order dynamics. The structure was derived from Gauss-... In “<i>A Self-linking Field Formalism</i>” I establish a self-dual field structure with higher order self-induced symmetries that reinforce the first-order dynamics. The structure was derived from Gauss-linking integrals in R<sup>3</sup> based on the Biot-Savart law and Ampere’s law applied to Heaviside’s equations, derived in strength-independent fashion in “<i>Primordial Principle of Self-Interaction</i>”. The derivation involves Geometric Calculus, topology, and field equations. My goal in this paper is to derive the simplest solution of a self-stabilized solitonic structure and discuss this model of a neutrino. 展开更多
关键词 Self-Stabilized field Theory First-Order Dynamics The Biot-Savart law The Ampere’s law Neutrino Heaviside Equations Gravitational field Solitons SELF-DUAL Gauss-Linking
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