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Time, Length, and Mass Are Derived Quantities
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作者 Tower Chen Zeon Chen 《Journal of Modern Physics》 2016年第10期1192-1199,共8页
Fundamental units of measurements are kilograms, meters, and seconds—in regards to mass length, and time. All other measurements in mechanical quantities including kinetic quantities and dynamic quantities are called... Fundamental units of measurements are kilograms, meters, and seconds—in regards to mass length, and time. All other measurements in mechanical quantities including kinetic quantities and dynamic quantities are called derived units. These derived units can be expressed in terms of fundamental units, such as acceleration, area, energy, force, power, velocity and volume. Derived quantities will be referred to as time, length, and mass. In order to explain that fundamental units are not equivalent with fundamental quantities, we need to understand the contraction of time and length in Special Relativity. If we choose the velocity of light as fundamental quantity and length and time as derived quantities, then we are able to construct three-dimensional space-time frames. Three-dimensional space-time frames representing time with polar coordination, time contraction and length contraction can be shown graphically. 展开更多
关键词 Fundamental Units Fundamental quantities Derived Units Derived quantities Special Relativity Constant Velocity of Light Three-Dimensional Space-Time Frame
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Conformal invariance and Hojman conserved quantities of first order Lagrange systems 被引量:9
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作者 陈向炜 刘畅 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3180-3184,共5页
In this paper the conformal invariance by infinitesimal transformations of first order Lagrange systems is discussed in detail. The necessary and sufficient conditions of conformal invariance and Lie symmetry simultan... In this paper the conformal invariance by infinitesimal transformations of first order Lagrange systems is discussed in detail. The necessary and sufficient conditions of conformal invariance and Lie symmetry simultaneously by the action of infinitesimal transformations are given. Then it gets the Hojman conserved quantities of conformal invariance by the infinitesimal transformations. Finally an example is given to illustrate the application of the results. 展开更多
关键词 first order Lagrange systems infinitesimal transformation conformal invariance Hojman conserved quantities
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Conformal invariance and conserved quantities of dynamical system of relative motion 被引量:7
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作者 陈向炜 赵永红 李彦敏 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3139-3144,共6页
This paper discusses in detail the conformal invariance by infinitesimal transformations of a dynamical system of relative motion. The necessary and sufficient conditions of conformal invariance and Lie symmetry are g... This paper discusses in detail the conformal invariance by infinitesimal transformations of a dynamical system of relative motion. The necessary and sufficient conditions of conformal invariance and Lie symmetry are given simultaneously by the action of infinitesimal transformations. Then it obtains the conserved quantities of conformal invariance by the infinitesimal transformations. Finally an example is given to illustrate the application of the results. 展开更多
关键词 dynamical system of relative motion infinitesimal transformation conformal invariance conserved quantities
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Conformal invariance and conserved quantities of non-conservative Lagrange systems by point transformations 被引量:3
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作者 刘畅 梅凤翔 郭永新 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第2期395-399,共5页
This paper studies the conformal invariance by infinitesimal point transformations of non-conservative Lagrange systems. It gives the necessary and sufficient conditions of conformal invariance by the action of infini... This paper studies the conformal invariance by infinitesimal point transformations of non-conservative Lagrange systems. It gives the necessary and sufficient conditions of conformal invariance by the action of infinitesimal point transformations being Lie symmetric simultaneously. Then the Noether conserved quantities of conformal invariance are obtained. Finally an illustrative example is given to verify the results. 展开更多
关键词 non-conservative Lagrange systems point transformations conformal invariance conserved quantities
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Mei symmetry and new conserved quantities of Tzénoff equations for higher-order nonholonomic system 被引量:3
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作者 ZHENG Shiwang ZHENG Wen 《商丘师范学院学报》 CAS 2012年第12期46-50,共5页
In this paper,the Mei symmetry of Tzénoff equations for the higher-order nonholonomic system and the new conserved quantities derived from that are researched,and the function expression of new conserved quantiti... In this paper,the Mei symmetry of Tzénoff equations for the higher-order nonholonomic system and the new conserved quantities derived from that are researched,and the function expression of new conserved quantities and criterion equation which deduces these conserved quantities are presented.This result establishes the theory basis for further researches on conservation laws of Tzénoff equations of the higher-order nonholonomic constraint system. 展开更多
关键词 higher-order nonholonomic constraint system Tzénoff equations Mei symmetry new conserved quantities
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Mei Symmetry and New Conserved Quantities of Tzénoff Equations for the Variable Mass Higher-Order Nonholonomic System 被引量:1
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作者 郑世旺 王建波 +1 位作者 陈向炜 解加芳 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第2期1-4,共4页
Operational systems of spacecraft are general variable mass mechanics systems,and their symmetries and conserved quantities imply profound physical rules of the space system.We study the Mei symmetry of Tzénoff e... Operational systems of spacecraft are general variable mass mechanics systems,and their symmetries and conserved quantities imply profound physical rules of the space system.We study the Mei symmetry of Tzénoff equations for a variable mass nonholonomic system and the new conserved quantities derived.The function expression of the new conserved quantities and the criterion equation which deduces these conserved quantities are presented.This result has some theoretical values in further research of conservation laws obeyed by the variable mass system. 展开更多
关键词 quantities CONSERVED SYMMETRY
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Computation of focus quantities of three-dimensional polynomial systems 被引量:1
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作者 Valery G.Romanovski Douglas S.Shafer 《上海师范大学学报(自然科学版)》 2014年第5期529-544,共16页
Fix a collection of polynomial vector fields on R3with a singularity at the origin,for every one of which the linear part at the origin has two pure imaginary and one non-zero eigenvalue. Some such systems admit a loc... Fix a collection of polynomial vector fields on R3with a singularity at the origin,for every one of which the linear part at the origin has two pure imaginary and one non-zero eigenvalue. Some such systems admit a local analytic first integral,which then defines a local center manifold of the system. Conditions for existence of a first integral are given by the vanishing certain polynomial or rational functions in the coefficients of the system called focus quantities. In this paper we prove that the focus quantities have a structure analogous to that in the two-dimensional case and use it to formulate an efficient algorithm for computing them. 展开更多
关键词 INTEGRABILITY center conditions focus quantities
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Geometric quantities of lower doubly excited bound states of helium
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作者 周成栋 余岳武 +1 位作者 杨三江 乔豪学 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第3期160-164,共5页
Expectation values of single electron and interelectronic geometric quantities such as <γ>,<γ_(12)> ,<γ_(<)> , <γ_(>)>,<cosθ_(12)> and <θ_(12)> are calculated for doubly... Expectation values of single electron and interelectronic geometric quantities such as <γ>,<γ_(12)> ,<γ_(<)> , <γ_(>)>,<cosθ_(12)> and <θ_(12)> are calculated for doubly excited 2pnp ^(1)P^(e)(3 ≤ n ≤ 5), 2pnp ^(3)P^(e)(2 ≤ n ≤ 5)and 2pnd ^(1,3)D°(3 ≤ n ≤ 5) states of helium using Hylleraas-B-spline basis set. The energy levels converge to at least 10 significant digits in our calculations.The extrapolated values of geometric quantities except for <θ_(12)> reach 10 significant digits as well;<θ_(12)> reaches at least 7 significant digits using a multipole expansion approach. Our results provide a precise reference for future research. 展开更多
关键词 doubly excited states unnatural parity Hylleraas-B-spline geometric quantities
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Conformal invariance and generalized Hojman conserved quantities of mechanico-electrical systems
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作者 李元成 夏丽莉 王小明 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4643-4649,共7页
This paper studies conformal invariance and generalized Hojman conserved quantities of mechanico-electrical systems. The definition and the determining equation of conformal invariance for mechanico-electrical systems... This paper studies conformal invariance and generalized Hojman conserved quantities of mechanico-electrical systems. The definition and the determining equation of conformal invariance for mechanico-electrical systems are provided. The conformal factor expression is deduced from conformal invariance and Lie symmetry under the infinitesimal single- parameter transformation group. The generalized Hojman conserved quantities from the conformal invariance of the system are given. An example is given to illustrate the application of the result. 展开更多
关键词 mechanico-electrical systems conformal invariance conformal factor generalized Hojman conserved quantities
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Conformal invariance and Hojman conserved quantities of canonical Hamilton systems
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作者 刘畅 刘世兴 +1 位作者 梅凤翔 郭永新 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期856-860,共5页
This paper discusses the conformal invariance by infinitesimal transformations of canonical Hamilton systems. The necessary and sufficient conditions of conformal invarianee being Lie symmetrical simultaneously by the... This paper discusses the conformal invariance by infinitesimal transformations of canonical Hamilton systems. The necessary and sufficient conditions of conformal invarianee being Lie symmetrical simultaneously by the action of infinitesimal transformations are given. The determining equations of the conformal invariance are gained. Then the Hojman conserved quantities of conformal invariance by special infinitesimal transformations are obtained. Finally an illustrative example is given to verify the results. 展开更多
关键词 canonical Hamilton systems infinitesimal transformations conformal invariance Hoj man conserved quantities
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Thermodynamical quantities around a RNAdS black hole
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作者 米丽琴 黎忠恒 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第6期1184-1189,共6页
The entropy density, energy density, pressure and equation of state around the RNAdS black hole are calculated in the WKB approximation on the Teukolsky-type master equation. The appearance of spin-dependent terms is ... The entropy density, energy density, pressure and equation of state around the RNAdS black hole are calculated in the WKB approximation on the Teukolsky-type master equation. The appearance of spin-dependent terms is demonstrated. The existence of these terms shows that the black hole radiation is not exactly thermal radiation and the black hole entropy is not strictly proportional to the area of the event horizon. 展开更多
关键词 thermodynamical quantities equation of state RNAdS black hole WKB approximation Boulware state
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Comparison between Cooling Rate Dependence of Macroscopic and Microscopic Quantities in Simulated Aluminium Glass
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作者 刘长松 朱震刚 《Chinese Physics Letters》 SCIE CAS CSCD 2000年第11期821-823,共3页
Constant-pressure molecular dynamics simulations and an analysis of the local atomic structures have been performed to study the cooling rate dependence of some macroscopic and microscopic quantities in aluminium glas... Constant-pressure molecular dynamics simulations and an analysis of the local atomic structures have been performed to study the cooling rate dependence of some macroscopic and microscopic quantities in aluminium glass.Macroscopic quantities,enthalpy and density,see an observable but small dependence on the cooling rate.Icosahedral ordering units exhibit strong cooling rate dependence,which is responsible for the dependence of the enthalpy and the density on the cooling rate;while the almost independence of some microstructural units such as the 1541,1431 and 1421 pairs of the cooling rate may lead to a small dependence of the enthalpy and the density on the cooling rate. 展开更多
关键词 quantities INDEPENDENCE ENTHALPY
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World Journal of Gastroenterology standard of quantities and units
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《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第40期i0005-i0005,共1页
关键词 World Journal of Gastroenterology standard of quantities and units In AZ
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Conserved quantities and symmetries related to stochastic Hamiltonian systems
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作者 尚玫 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3161-3167,共7页
In this paper symmetries and conservation laws for stochastic dynamical systems are discussed in detail. Determining equations for infinitesimal approximate symmetries of Ito and Stratonovich dynamical systems are der... In this paper symmetries and conservation laws for stochastic dynamical systems are discussed in detail. Determining equations for infinitesimal approximate symmetries of Ito and Stratonovich dynamical systems are derived. It shows how to derive conserved quantities for stochastic dynamical systems by using their symmetries without recourse to Noether's theorem. 展开更多
关键词 stochastic dynamical systems symmetries and conserved quantities Ito and Stratanovich dynamical systems
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World Journal of Gastroenterology standard of quantities and units
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《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第9期i005-i005,共1页
关键词 World Journal of Gastroenterology standard of quantities and units In WANG
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World Journal of Gastroenterology standard of quantities and units
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《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第35期i0001-i0001,共1页
关键词 World Journal of Gastroenterology standard of quantities and units In
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World Journal of Gastroenterology standard of quantities and units
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《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第15期2476-2476,共1页
关键词 World Journal of Gastroenterology standard of quantities and units In
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World Journal of Gastroenterology standard of quantities and units
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《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第17期i005-i005,共1页
关键词 World Journal of Gastroenterology standard of quantities and units In
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World Journal of Gastroenterology standard of quantities and units
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《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第9期1492-1492,共1页
关键词 In World Journal of Gastroenterology standard of quantities and units
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World Journal of Gastroenterology standard of quantities and units
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《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第41期i0001-i0001,共1页
关键词 In World Journal of Gastroenterology standard of quantities and units
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