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RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CON-TINUUM THEORIES (Ⅱ)—MICROMORPHIC CONTINUUM THEORY AND COUPLE STRESS THEORY 被引量:2
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第10期1126-1133,共8页
The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theor... The purpose is to reestablish the balance laws of momentum, angular momentum and energy and to derive the corresponding local and nonlocal balance equations for micromorphic continuum mechanics and couple stress theory. The desired results for micromorphic continuum mechanics and couple stress theory are naturally obtained via direct transitions and reductions from the coupled conservation law of energy for micropolar continuum theory, respectively. The basic balance laws and equations for micromorphic continuum mechanics and couple stress theory are constituted by combining these results derived here and the traditional conservation laws and equations of mass and microinertia and the entropy inequality. The incomplete degrees of the former related continuum theories are clarified. Finally, some special cases are conveniently derived. 展开更多
关键词 micromorphic continuum couple stress theory COUPLED basic balance law balance equation
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Mechanical Properties of Simple s-p Metals, and Defect Energies from Electron Theory and from Interatomic Force Laws 被引量:1
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作者 N.H.March(Oxford University, Oxford, U.K.) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第2期81-85,共5页
The cleavage force F(z) needed to separate parallel atomic planes by a distance z is first discussed for simple s-p metals using density functional theory.For the s-p nearly free-electron metals the linearized Thomas-... The cleavage force F(z) needed to separate parallel atomic planes by a distance z is first discussed for simple s-p metals using density functional theory.For the s-p nearly free-electron metals the linearized Thomas-Fermi equation is solved self-consistently in the cases of (a) semi-infinite planes of jellium (i.e. smeared uniform positive ions) and (b) a semi-infinite cylinder of finite radius, cleaved by a plane perpendicular to its axis. In (a), the elastic region has the form F(z)=Az ∝ Zrs-11/2, where rs is the mean interelectronic distance in the jellium model. Size effects are then considered, with possible relevance to atomic force microscopy.Defect energies are treated, using both electron theory and pair force laws. 展开更多
关键词 and Defect Energies from Electron theory and from Interatomic Force laws Mechanical Properties of Simple s-p Metals Rev
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Perturbation Theory of Fractional Lagrangian System and Fractional Birkhoffian System 被引量:3
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作者 Song Chuanjing Zhang Yi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第2期353-360,共8页
Perturbation to symmetry and adiabatic invariants are studied for the fractional Lagrangian system and the fractional Birkhoffian system in the sense of Riemann-Liouville derivatives.Firstly,the fractional Euler-Lagra... Perturbation to symmetry and adiabatic invariants are studied for the fractional Lagrangian system and the fractional Birkhoffian system in the sense of Riemann-Liouville derivatives.Firstly,the fractional Euler-Lagrange equation,the fractional Birkhoff equations as well as the fractional conservation laws for the two systems are listed.Secondly,the definition of adiabatic invariant for fractional mechanical system is given,then perturbation to symmetry and adiabatic invariants are established for the fractional Lagrangian system and the fractional Birkhoffian system under the special and general infinitesimal transformations,respectively.Finally,two examples are devoted to illustrate the results. 展开更多
关键词 perturbation theory FRACTIONAL conservation law Riemann LIOUVILLE derivative FRACTIONAL EULER-LAGRANGE EQUATION FRACTIONAL BIRKHOFF EQUATION
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Symmetry Reduction, Exact Solutions, and Conservation Laws of (2+1)-Dimensional Burgers Korteweg-de Vries Equation 被引量:2
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作者 DONG Zhong-Zhou LIU Xi-Qiang BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期15-20,共6页
Using the classical Lie method of infinitesimals, we first obtain the symmetry of the (2+1)-dimensional Burgers-Korteweg-de-Vries (3D-BKdV) equation. Then we reduce the 3D-BKdV equation using the symmetry and giv... Using the classical Lie method of infinitesimals, we first obtain the symmetry of the (2+1)-dimensional Burgers-Korteweg-de-Vries (3D-BKdV) equation. Then we reduce the 3D-BKdV equation using the symmetry and give some exact solutions of the 3D-BKdV equation. When using the direct method, we restrict a condition and get a relationship between the new solutions and the old ones. Given a solution of the 3D-BKdV equation, we can get a new one from the relationship. The relationship between the symmetry obtained by using the classical Lie method and that obtained by using the direct method is also mentioned. At last, we give the conservation laws of the 3D-BKdV equation. 展开更多
关键词 3D-BKdV equation classical Lie method direct method conservation laws
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Leak Detection in Water Distribution Systems Using Bayesian Theory and Fisher’s Law 被引量:1
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作者 张宏伟 王丽娟 《Transactions of Tianjin University》 EI CAS 2011年第3期181-186,共6页
A leak detection method based on Bayesian theory and Fisher’s law was developed for water distribution systems. A hydraulic model was associated with the parameters of leaks (location, extent). The randomness of para... A leak detection method based on Bayesian theory and Fisher’s law was developed for water distribution systems. A hydraulic model was associated with the parameters of leaks (location, extent). The randomness of parameter values was quantified by probability density function and updated by Bayesian theory. Values of the parameters were estimated based on Fisher’s law. The amount of leaks was estimated by back propagation neural network. Based on flow characteristics in water distribution systems, the location of leaks can be estimated. The effectiveness of the proposed method was illustrated by simulated leak data of node pressure head and flow rate of pipelines in a test pipe network, and the leaks were spotted accurately and renovated on time. 展开更多
关键词 water distribution systems LEAK DETECTION EPANET Fisher's law Bayesian theory back propagationneural network
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Q-Theory: A Connection between Newton’s Law and Coulomb’s Law? 被引量:1
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作者 Christopher Pilot 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第2期632-660,共29页
Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<... Assuming a Winterberg model for space where the vacuum consists of a very stiff two-component superfluid made up of positive and negative mass planckions, Q theory is the hypothesis, that Planck charge, <i>q<sub>pl</sub></i>, was created at the same time as Planck mass. Moreover, the repulsive force that like-mass planckions experience is, in reality, due to the electrostatic force of repulsion between like charges. These forces also give rise to what appears to be a gravitational force of attraction between two like planckions, but this is an illusion. In reality, gravity is electrostatic in origin if our model is correct. We determine the spring constant associated with planckion masses, and find that, <img src="Edit_770c2a48-039c-4cc9-8f66-406c0cfc565c.png" width="90" height="15" alt="" />, where <i>ζ</i>(3) equals Apery’s constant, 1.202 …, and, <i>n</i><sub>+</sub>(0)=<i>n</i>_(0), is the relaxed, <i>i.e.</i>, <img src="Edit_813d5a6f-b79a-49ba-bdf7-5042541b58a0.png" width="25" height="12" alt="" />, number density of the positive and negative mass planckions. In the present epoch, we estimate that, <i>n</i><sub>+</sub>(0) equals, 7.848E54 m<sup>-3</sup>, and the relaxed distance of separation between nearest neighbor positive, or negative, planckion pairs is, <i>l</i><sub>+</sub>(0)=<i>l</i><sub>_</sub>(0)=5.032E-19 meters. These values were determined using box quantization for the positive and negative mass planckions, and considering transitions between energy states, much like as in the hydrogen atom. For the cosmos as a whole, given a net smeared macroscopic gravitational field of, <img src="Edit_efc8003d-5297-4345-adac-4ac95536934d.png" width="80" height="15" alt="" />, due to all the ordinary, and bound, matter contained within the observable universe, an average displacement from equilibrium for the planckion masses is a mere 7.566E-48 meters, within the vacuum made up of these particles. On the surface of the earth, where, <i>g</i>=9.81m/s<sup>2</sup>, the displacement amounts to, 7.824E-38 meters. All of these displacements are due to increased gravitational pressure within the vacuum, which in turn is caused by applied gravitational fields. The gravitational potential is also derived and directly related to gravitational pressure. 展开更多
关键词 Extended Gravity Winterberg Model Planckion Mass theory Modified Quantum Vacuum Planck Charge Newton’s Law Coulomb’s Law Dark Energy
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Semi-classical theory and experimental research for polarization flipping in a single frequency laser with feedback effect 被引量:1
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作者 陈文学 张书练 +1 位作者 张鹏 曾召利 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期76-80,共5页
In this paper, we propose a semi-classical theory to successfully explain the polarization flipping in a single frequency laser. An experimental setup is built to verify this theory. The observed experimental phenomen... In this paper, we propose a semi-classical theory to successfully explain the polarization flipping in a single frequency laser. An experimental setup is built to verify this theory. The observed experimental phenomena are consistent with the theoretical analysis. We perform phase retardation measurements of birefringent components using this experimental system. The results show that the measurement repeatability is 0.12° and the measurement accuracy is 0.22°. 展开更多
关键词 semi-classical theory INTERFERENCE BIREFRINGENCE
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Equation of Motion of a Mass Point in Gravitational Field and Classical Tests of Gauge Theory of Gravity
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作者 WU Ning ZHANG Da-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期503-511,共9页
A systematic method is developed to studY the classical motion of a mass point in gravitational gauge field. First, by using Mathematica, a spherical symmetric solution of the field equation of gravitational gauge fie... A systematic method is developed to studY the classical motion of a mass point in gravitational gauge field. First, by using Mathematica, a spherical symmetric solution of the field equation of gravitational gauge field is obtained, which is just the traditional Schwarzschild solution. Combining the principle of gauge covariance and Newton's second law of motion, the equation of motion of a mass point in gravitational field is deduced. Based on the spherical symmetric solution of the field equation and the equation of motion of a mass point in gravitational field, we can discuss classical tests of gauge theory of gravity, including the deflection of light by the sun, the precession of the perihelia of the orbits of the inner planets and the time delay of radar echoes passing the sun. It is found that the theoretical predictions of these classical tests given by gauge theory of gravity are completely the same as those given by general relativity. 展开更多
关键词 classical tests of gauge theory of gravity gauge theory of gravity classical solution of field equation Newton's second law of motion
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A note on teleparallel Killing vector fields in Bianchi type Ⅷ and Ⅸ space-times in teleparallel theory of gravitation
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作者 Ghulam Shabbir Amjad Ali Suhail Khan 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期88-93,共6页
In this paper we classify Bianchi type Ⅷ and IX space-times according to their teleparallel Killing vector fields in the teleparallel theory of gravitation by using a direct integration technique. It turns out that t... In this paper we classify Bianchi type Ⅷ and IX space-times according to their teleparallel Killing vector fields in the teleparallel theory of gravitation by using a direct integration technique. It turns out that the dimensions of the teleparallel Killing vector fields are either 4 or 5. From the above study we have shown that the Killing vector fields for Bianchi type Ⅷ and Ⅸ space-times in the context of teleparallel theory are different from that in general relativity. 展开更多
关键词 WeitzenbSck geometry teleparallel theory of gravitation conservation laws
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BASIC EQUATIONS, THEORY AND PRINCIPLE OF COMPUTATIONAL STOCK MARKET (Ⅲ)—BASIC THEORIES
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作者 云天铨 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第8期861-868,共8页
By basic equations, two basic theories are presented: 1.Theory of stock's value v *(t)=v *(0) exp (ar * 2t); 2. Theory of conservation of stock's energy. Let stock's energy be defined as a q... By basic equations, two basic theories are presented: 1.Theory of stock's value v *(t)=v *(0) exp (ar * 2t); 2. Theory of conservation of stock's energy. Let stock's energy be defined as a quadratic function of stock's price v and its derivative , =Av 2+ Bv+C 2+Dv, under the constraint of basic equation, the problem was reduced to a problem of constrained optimization along optimal path. Using Lagrange multiplier and Euler equation of variation method, it can be proved that keeps conservation for any v,. The application of these equations and theories on judgement and analysis of tendency of stock market are given, and the judgement is checked to be correct by the recorded tendency of Shenzhen and Shanghai stock markets. 展开更多
关键词 political economics theory of value of goods variational method Euler equation conservation law
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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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Relativity Theory and Paraquantum Logic—Part II:Fundamentals of an Unified Calculation 被引量:1
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作者 Joao Inacio Da Silva Filho 《Journal of Modern Physics》 2012年第9期972-988,共17页
The studies of the PQL are based on propagation of Paraquantum logical states ψ in a representative Lattice of four vertices. Based in interpretations that consider resulting information of measurements in physical s... The studies of the PQL are based on propagation of Paraquantum logical states ψ in a representative Lattice of four vertices. Based in interpretations that consider resulting information of measurements in physical systems are found paraquantum equations for computation of the physical quantities in real physical systems. In the first part of this work we presented a study of Relativity theory which involved the time and the space with their characteristics as degrees of evidence applied in Paraquantum Logical Model. Now, in this second Part we present a study of application of the PQL in resolution of phenomena of physical systems that involve concepts of the Relativity Theory and the correlation of these effects with the Newtonian Universe and Quantum Mechanics. Considering physical fundamental quantities varying periodically in amplitude, we introduce the paraquantum equations which consider frequency in the analysis. From of these mathematical relationships obtained in the PQL Lattice some main physical constants related to the studies of De Broglie appeared. With the equations of Energy obtained through the analyses is demonstrated that the Paraquantum Logic is capable to correlate values and to unify the several study areas of the Physical Science. 展开更多
关键词 Paraconsistent Logic Paraquantum Logic Classical Physic Relativity theory Quantum Mechanics
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Classical Theory of Advance of Perihelion of Mercury with Velocity Dependent Inertial and Gravitational Masses
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作者 Erich R. Bagge (Institute for Pure and Applied Nuclear Physics, Christian Albrechts University, Kiel,Germany) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期87-98,共12页
It is shown that Mercury's motion of the perihelion around the Sun, which is believed to be explicable quantitatively only by general relativity, can be fully understood within the frame of the dynamics of special... It is shown that Mercury's motion of the perihelion around the Sun, which is believed to be explicable quantitatively only by general relativity, can be fully understood within the frame of the dynamics of special relativity. It is only necessary to take into consideration the relativistic dependence of the planet's inertial and gravitational masses on its velocity (relative to the Sun) in the conservation equations for energy, and linear and angular momenta in the gravitational field. The physical Problem is reduced to a singular, nonlinear differential equation, which is solved numerically for the planet Mercury. The advance of the perihelion of Mercury is shown to be = 42.087' for a period of 100 years, which is in agreement with the as- tronomical observations and the result (by analytical approximations) of general relativity. 展开更多
关键词 Planet mercury Advance of perihelion Classical theory Velocity dependent inertial and gravitational masses Agreement with observations.
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Monty Hall Problem and the Principle of Equal Probability in Measurement Theory
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作者 Shiro Ishikawa 《Applied Mathematics》 2012年第7期788-794,共7页
In this paper, we study the principle of equal probability (i.e., unless we have sufficient reason to regard one possible case as more probable than another, we treat them as equally probable) in measurement theory (i... In this paper, we study the principle of equal probability (i.e., unless we have sufficient reason to regard one possible case as more probable than another, we treat them as equally probable) in measurement theory (i.e., the theory of quantum mechanical world view), which is characterized as the linguistic turn of quantum mechanics with the Copenhagen interpretation. This turn from physics to language does not only realize theremarkable extensionof quantum mechanicsbut alsoestablish the method of science. Our study will be executed in the easy example of the Monty Hall problem. Although our argument is simple, we believe that it is worth pointing out the fact that the principle of equal probability can be, for the first time, clarified in measurement theory (based on the dualism) and not the conventional statistics (based on Kolmogorov’s probability theory). 展开更多
关键词 Linguistic Interpretation Quantum and Classical Measurement theory PHILOSOPHY of Statistics FISHER Maximum LIKELIHOOD Method Bayes’ Theorem
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A Back Look on the Binary Phase Diagrams of Metals from the Mass Action Law and the Coexistence Theory of Metallic Melts
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作者 Jian Zhang Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China 《Journal of University of Science and Technology Beijing》 CSCD 2001年第1期15-19,共5页
According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results s... According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration. 展开更多
关键词 ACTIVITY phase diagram the mass action law the coexistence theory
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Discovering exact,gauge-invariant,local energy–momentum conservation laws for the electromagnetic gyrokinetic system by high-order field theory on heterogeneous manifolds
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作者 Peifeng FAN Hong QIN Jianyuan XIAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第10期120-136,共17页
Gyrokinetic theory is arguably the most important tool for numerical studies of transport physics in magnetized plasmas.However,exact local energy–momentum conservation laws for the electromagnetic gyrokinetic system... Gyrokinetic theory is arguably the most important tool for numerical studies of transport physics in magnetized plasmas.However,exact local energy–momentum conservation laws for the electromagnetic gyrokinetic system have not been found despite continuous effort.Without such local conservation laws,energy and momentum can be instantaneously transported across spacetime,which is unphysical and casts doubt on the validity of numerical simulations based on the gyrokinetic theory.The standard Noether procedure for deriving conservation laws from corresponding symmetries does not apply to gyrokinetic systems because the gyrocenters and electromagnetic field reside on different manifolds.To overcome this difficulty,we develop a high-order field theory on heterogeneous manifolds for classical particle-field systems and apply it to derive exact,local conservation laws,in particular the energy–momentum conservation laws,for the electromagnetic gyrokinetic system.A weak Euler–Lagrange(EL)equation is established to replace the standard EL equation for the particles.It is discovered that an induced weak EL current enters the local conservation laws,and it is the new physics captured by the high-order field theory on heterogeneous manifolds.A recently developed gauge-symmetrization method for high-order electromagnetic field theories using the electromagnetic displacement-potential tensor is applied to render the derived energy–momentum conservation laws electromagnetic gauge-invariant. 展开更多
关键词 electromagnetic gyrokinetic system high-order field theory heterogeneous manifolds exact local energy–momentum conservation laws weak Euler–Lagrange equation gauge-invariant theory
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The Bridge to a Western Confucianism:Between Legal Theory and Private Law
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作者 Domenico Bilotti 《Cultural and Religious Studies》 2019年第8期456-460,共5页
The aim of this essay is to analyse the future of Confucianism in Western societies or,at least,through the exegesis of Western scholars.To realize this overview definitely means to verify how Confucian thought crosse... The aim of this essay is to analyse the future of Confucianism in Western societies or,at least,through the exegesis of Western scholars.To realize this overview definitely means to verify how Confucian thought crossed many contemporary and later theories,especially in juridical fields as the theory of private law and the public comparative law.That system of customary rules and pragmatic ethics did not fail to face the modernity by enlarging its views in the context of much more complex societies:So,a typical phenomenon of Eastern civilities,to the point that it is generally considered the most peculiar inheritance of both Chinese spirituality and administrative political science,became an interesting and suggestive test bench for different starting points.If it is correct to say that this is not a proper nowadays stance(remembering the praise of Leibniz and Voltaire,for instance),it is even more likely that Confucianism will catch the attention of a larger academic audience also in the nearest future and not only narrowing its rise to the enormous economic growth of the Chinese influence and ruling role in the world,directly getting a level of strength not far from the American governance.Unsurprisingly,the first defined approaches to a Western Confucianism,mixing elements from its absolutely unique written or traditional sources and aspects taken from the comparison with other cultures,are still coming from United States’universities,in the scientific field of sinology and,step by step,comparative law’s scholars and legal theorists.This fascinating development that opens up Confucian ethics to a bigger spectre of teachings and belongings is happening while Confucian rituals,temples,and precepts are reaching in modern days China an always more cohesive and aggregating religious phenomenology.The West looks for ideas,while the East is trying to find stability around a metaphysical substructure of common values to prevent conflicts and to keep societies safe. 展开更多
关键词 ecclesiastical LAW CONFUCIANISM LEGAL theory PRIVATE LAW
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A Classical Field Theory of Gravity and Electromagnetism
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作者 Raymond J. Beach 《Journal of Modern Physics》 2014年第10期928-939,共12页
A classical field theory of gravity and electromagnetism is developed. The starting point of the theory is the Maxwell equations which are directly tied to the Riemann-Christoffel curvature tensor. This is done throug... A classical field theory of gravity and electromagnetism is developed. The starting point of the theory is the Maxwell equations which are directly tied to the Riemann-Christoffel curvature tensor. This is done through the derivatives of the Maxwell tensor which are equated to a vector field ?contracted with the curvature tensor, i.e., . The electromagnetic portion of the theory is shown to be equivalent to the classical Maxwell equations with the addition of a hidden variable. Because the proposed equations describing electromagnetism and gravity differ from the classical Maxwell-Einstein equations, their ability to describe classical physics is shown for several situations by direct calculation. The inclusion of antimatter and its behavior in a gravitational field, and the possibility of particle-like solutions exhibiting quantized charge, mass and angular momentum are discussed. 展开更多
关键词 CLASSICAL Field theory GRAVITATION and Electromagnetism General RELATIVITY ANTIMATTER ANTIMATTER GRAVITY Hidden Variable Theories RIEMANN Geometry
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Western Theory and the Study of Classical Chinese Literature in North America
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作者 Zhang Wanmin Wu Lingwei 《Contemporary Social Sciences》 2019年第6期99-117,共19页
In the second half of the 20th century,humanistic studies in the West witnessed a“theory explosion”.Unlike traditional European Sinology,American Sinology borrowed the latest Western theoretical approaches and forme... In the second half of the 20th century,humanistic studies in the West witnessed a“theory explosion”.Unlike traditional European Sinology,American Sinology borrowed the latest Western theoretical approaches and formed a unique feature.The emerging Western theory also influenced the study of classical Chinese literature in the USA,with each Sinologist exhibiting a different tendency.In the context of the development of American Sinology and Western theory,this paper examines the Sinologists’change of attitudes in different development stages to unveil the characteristics and tendencies of the study of classical Chinese literature in North America. 展开更多
关键词 AMERICAN SINOLOGY CLASSICAL Chinese LITERATURE WESTERN theory
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High-order field theory and a weak Euler–Lagrange–Barut equation for classical relativistic particle-field systems
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作者 范培锋 陈强 +1 位作者 肖建元 于治 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期42-54,共13页
In both quantum and classical field systems,conservation laws such as the conservation of energy and momentum are widely regarded as fundamental properties.A broadly accepted approach to deriving conservation laws is ... In both quantum and classical field systems,conservation laws such as the conservation of energy and momentum are widely regarded as fundamental properties.A broadly accepted approach to deriving conservation laws is built using Noether's method.However,this procedure is still unclear for relativistic particle-field systems where particles are regarded as classical world lines.In the present study,we establish a general manifestly covariant or geometric field theory for classical relativistic particle-field systems.In contrast to quantum systems,where particles are viewed as quantum fields,classical relativistic particle-field systems present specific challenges.These challenges arise from two sides.The first comes from the mass-shell constraint.To deal with the mass-shell constraint,the Euler–Lagrange–Barut(ELB)equation is used to determine the particle's world lines in the four-dimensional(4D)Minkowski space.Besides,the infinitesimal criterion,which is a differential equation in formal field theory,is reconstructed by an integro-differential form.The other difficulty is that fields and particles depend on heterogeneous manifolds.To overcome this challenge,we propose using a weak version of the ELB equation that allows us to connect local conservation laws and continuous symmetries in classical relativistic particle-field systems.By applying a weak ELB equation to classical relativistic particle-field systems,we can systematically derive local conservation laws by examining the underlying symmetries of the system.Our proposed approach provides a new perspective on understanding conservation laws in classical relativistic particle-field systems. 展开更多
关键词 high-order field theory weak Euler-Lagrange-Barut equation infinitesimal criterion of symmetric condition Noether's theorem geometric conservation laws
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