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Assessing Criteria Weights by the Symmetry Point of Criterion (Novel SPC Method)–Application in the Efficiency Evaluation of the Mineral Deposit Multi-Criteria Partitioning Algorithm
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作者 Zoran Gligoric Milos Gligoric +2 位作者 Igor Miljanovic Suzana Lutovac Aleksandar Milutinovic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期955-979,共25页
Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very impor... Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very important task in solving multi-criteria decision-making problems.Three methods are commonly used for assessing the weights of criteria:objective,subjective,and integrated methods.In this study,an objective approach is proposed to assess the weights of criteria,called SPCmethod(Symmetry Point of Criterion).This point enriches the criterion so that it is balanced and easy to implement in the process of the evaluation of its influence on decision-making.The SPC methodology is systematically presented and supported by detailed calculations related to an artificial example.To validate the developed method,we used our numerical example and calculated the weights of criteria by CRITIC,Entropy,Standard Deviation and MEREC methods.Comparative analysis between these methods and the SPC method reveals that the developedmethod is a very reliable objective way to determine the weights of criteria.Additionally,in this study,we proposed the application of SPCmethod to evaluate the efficiency of themulti-criteria partitioning algorithm.The main idea of the evaluation is based on the following fact:the greater the uniformity of the weights of criteria,the higher the efficiency of the partitioning algorithm.The research demonstrates that the SPC method can be applied to solving different multi-criteria problems. 展开更多
关键词 Multi-criteria decision-making weights of criteria symmetry point of criterion mineral deposit partitioning algorithm performance evaluation
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Multiple Darboux–B?cklund transformations via truncated Painleve′ expansion and Lie point symmetry approach 被引量:3
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作者 Shuai-Jun Liu Xiao-Yan Tang Sen-Yue Lou 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期103-108,共6页
For a given truncated Painleve′ expansion of an arbitrary nonlinear Painleve′ integrable system, the residue with respect to the singularity manifold is known as a nonlocal symmetry, called the residual symmetry, wh... For a given truncated Painleve′ expansion of an arbitrary nonlinear Painleve′ integrable system, the residue with respect to the singularity manifold is known as a nonlocal symmetry, called the residual symmetry, which is proved to be localized to Lie point symmetries for suitable prolonged systems. Taking the Korteweg–de Vries equation as an example, the n-th binary Darboux–Ba¨cklund transformation is re-obtained by the Lie point symmetry approach accompanied by the localization of the n-fold residual symmetries. 展开更多
关键词 residue symmetry multiple Darboux-Baicklund transformation Lie point symmetry approach
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Lie point symmetry algebras and finite transformation groups of the general Broer-Kaup system 被引量:1
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作者 贾曼 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第6期1534-1544,共11页
Using a new symmetry group theory, the transformation groups and symmetries of the general Broer-Kaup system are obtained. The results are much simpler than those obtained via the standard approaches.
关键词 Lie point symmetry finite transformation group new symmetry group theory
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Lie Point Symmetries and Exact Solutions of Couple KdV Equations 被引量:5
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作者 QIAN Su-Ping TIAN Li-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4期582-586,共5页
The simple Lie point symmetry reduction procedure is used to obtain infinitely many symmetries to a new integrable system of coupled KdV equations. Using some symmetry subalgebra of the equations, five types of the si... The simple Lie point symmetry reduction procedure is used to obtain infinitely many symmetries to a new integrable system of coupled KdV equations. Using some symmetry subalgebra of the equations, five types of the significant similarity reductions are obtained by virtue of the Lie group approach, and obtain abundant solutions of the coupled KdV equations, such as the solitary wave solution, exponential solution, rational solution, polynomial solution, etc. 展开更多
关键词 coupled KdV equations Lie point symmetry exact solutions
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Noether conserved quantities and Lie point symmetries for difference nonholonomic Hamiltonian systems in irregular lattices 被引量:3
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作者 夏丽莉 陈立群 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期19-25,共7页
The Noether conserved quantities and the Lie point symmetries for difference nonholonomic Hamiltonian systems in irregular lattices are studied. The generalized Hamiltonian equations of the systems are given on the ba... The Noether conserved quantities and the Lie point symmetries for difference nonholonomic Hamiltonian systems in irregular lattices are studied. The generalized Hamiltonian equations of the systems are given on the basis of the transformation operators in the space of discrete Hamiltonians. The Lie transformations acting on the lattice, as well as the equations and the determining equations of the Lie symmetries are obtained for the nonholonomic Hamiltonian systems. The discrete analogue of the Noether conserved quantity is constructed by using the Lie point symmetries. An example is discussed to illustrate the results. 展开更多
关键词 discrete nonholonomic Hamiltonian systems Lie point symmetry Noether conservedquantity
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Noether conserved quantities and Lie point symmetries of difference Lagrange-Maxwell equations and lattices 被引量:2
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作者 傅景礼 聂宁明 +4 位作者 黄健飞 Jiménez Salvador 唐贻发 Vzquez Luis 赵维加 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2634-2641,共8页
This paper presents a method to find Noether-type conserved quantities and Lie point symmetries for discrete mechanico-electrical dynamical systems,which leave invuriant the set of solutions of the corresponding diffe... This paper presents a method to find Noether-type conserved quantities and Lie point symmetries for discrete mechanico-electrical dynamical systems,which leave invuriant the set of solutions of the corresponding difference scheme. This approach makes it possible to devise techniques for solving the Lagrange Maxwell equations in differences which correspond to mechanico-electrical systems,by adapting existing differential equations.In particular,it obtains a new systematic method to determine both the one-parameter Lie groups and the discrete Noether conserved quantities of Lie point symmetries for mechanico-electrical systems.As an application,it obtains the Lie point symmetries and the conserved quantities for the difference equation of a model that represents a capacitor microphone. 展开更多
关键词 Lagrange Maxwell equation Lie point symmetry discrete mechanico-electrical system conserved quantity
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Symmetry Groups and Exact Solutions of New(4+1)-Dimensional Fokas Equation 被引量:1
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作者 YANG Zheng-Zheng YAN Zhen-Ya 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期876-880,共5页
In this paper, we investigate symmetries of the new (4+1)-dimensional Fokas equation, including point symmetries and the potential symmetries. We firstly employ the algorithmic procedure of computing the point symm... In this paper, we investigate symmetries of the new (4+1)-dimensional Fokas equation, including point symmetries and the potential symmetries. We firstly employ the algorithmic procedure of computing the point symmetries. And then we transform the Fokas equation into a potential system and gain the potential symmetries of Fokas equation. Finally, we use the obtained point symmetries wave solutions and other solutions of the Fokas equation. and some constructive methods to get some doubly periodic In particular, some solitary wave solutions are also given. 展开更多
关键词 Fokas equation point symmetry potential symmetry solitary wave solution reduced form
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A symmetry-preserving difference scheme for high dimensional nonlinear evolution equations
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作者 辛祥鹏 陈勇 王云虎 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期99-104,共6页
In this paper, a procedure for constructing discrete models of the high dimensional nonlinear evolution equanons is presented. In order to construct the difference model, with the aid of the potential system of the or... In this paper, a procedure for constructing discrete models of the high dimensional nonlinear evolution equanons is presented. In order to construct the difference model, with the aid of the potential system of the original equation and compatibility condition, the difference equations which preserve all Lie point symmetries can be obtained. As an example, invariant difference models of the (2+1)-dimensional Burgers equation are presented. 展开更多
关键词 symmetry-preserving potential systems difference equation Lie point symmetry
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Lie Point Symmetries of Differential-Difference Equations
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作者 DINGWei TANGXiao-Yan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期645-648,共4页
In this paper, the classical Lie group approach is extended to find some Lie point symmetries of differentialdifference equations. It reveals that the obtained Lie point symmetries can constitute a Kac-Moody-Virasoro ... In this paper, the classical Lie group approach is extended to find some Lie point symmetries of differentialdifference equations. It reveals that the obtained Lie point symmetries can constitute a Kac-Moody-Virasoro algebra. 展开更多
关键词 Lie point symmetry differential-differerice equation Kac-Moody-Virasoro algebra
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General Formulations of Finite-field Method Classifiedby Symmetry for Molecular Linear and Nonlinear Polarizabilities
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作者 陈锡华 林晨升 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第5期369-380,共12页
The formulations of the finite-field approach to calculate the linear and non-linear optical coefficients (i, (ij, (ijk and (ijkl of a molecular system with different symmetries have been deduced and summarized. The p... The formulations of the finite-field approach to calculate the linear and non-linear optical coefficients (i, (ij, (ijk and (ijkl of a molecular system with different symmetries have been deduced and summarized. The possible choices of the energy sets of the 48 frequent point groups have been optimized and categorized into 11 classes. With the restriction of symmetry operators, a minimum of 9, no more than 21 energy points have to be calculated in order to determine the coefficients, except in the case of the first class to which C1 point group belongs and in which the 34 non-relative energy points selected in our uniform and general scheme are all needed. The symmetric operators that cause some of the tensor components to vanish have been demonstrated as well. 展开更多
关键词 nonlinear optical polarizability finite-field approach point group symmetry
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Birkhoff’s Theorem and Lie Symmetry Analysis
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作者 Avijit Mukherjee Subham B. Roy 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第4期1280-1297,共18页
Three dimensional space is said to be spherically symmetric if it admits SO(3) as the group of isometries. Under this symmetry condition, the Einstein’s Field equations for vacuum, yields the Schwarzschild Metric as ... Three dimensional space is said to be spherically symmetric if it admits SO(3) as the group of isometries. Under this symmetry condition, the Einstein’s Field equations for vacuum, yields the Schwarzschild Metric as the unique solution, which essentially is the statement of the well known Birkhoff’s Theorem. Geometrically speaking this theorem claims that the pseudo-Riemanian space-times provide more isometries than expected from the original metric holonomy/ansatz. In this paper we use the method of Lie Symmetry Analysis to analyze the Einstein’s Vacuum Field Equations so as to obtain the Symmetry Generators of the corresponding Differential Equation. Additionally, applying the Noether Point Symmetry method we have obtained the conserved quantities corresponding to the generators of the Schwarzschild Lagrangian and paving way to reformulate the Birkhoff’s Theorem from a different approach. 展开更多
关键词 Birkhoff’s Theorem Lie symmetry Analysis Noether point symmetry
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New Exact Solutions and Conservation Laws to (3+1)-Dimensional Potential-YTSF Equation 被引量:10
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作者 ZHANG Li-Hua LIU Xi-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期487-492,共6页
Using the modified find some new exact solutions to Lie point symmetry groups and also get conservation laws, of the CK's direct method, we build the relationship between new solutions and old ones and the (3+1)-d... Using the modified find some new exact solutions to Lie point symmetry groups and also get conservation laws, of the CK's direct method, we build the relationship between new solutions and old ones and the (3+1)-dimensional potentiaial-YTSF equation. Baaed on the invariant group theory, Lie symmetries of the (3+1)-dimensional potential-YTSF equation are obtained. We equation with the given Lie symmetry. 展开更多
关键词 new exact solutions Lie point symmetry groups conservation laws (3+1)-dimensional potential-YTSF equation
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Critical point symmetry for odd-odd nuclei and collective multiple chiral doublet bands 被引量:2
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作者 Yu Zhang Bin Qi Shuang-Quan Zhang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2021年第12期111-120,共10页
A critical point symmetry(CPS) for odd-odd nuclei is built in the core-particle coupling scheme with the even-even core assumed to follow the spherical to triaxially deformed shape phase transition. It is shown that t... A critical point symmetry(CPS) for odd-odd nuclei is built in the core-particle coupling scheme with the even-even core assumed to follow the spherical to triaxially deformed shape phase transition. It is shown that the model Hamiltonian can be approximately solved with the solutions being expressed in terms of the Bessel functions of irrational orders. In particular, the CPS predicts that collective multiple chiral doublets may exist in transitional odd-odd systems. 展开更多
关键词 collective model critical point symmetry multiple chiral doublet bands
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Streamlines in the Two-Dimensional Spreading of a Thin Fluid Film: Blowing and Suction Velocity Proportional to the Height 被引量:1
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作者 N. Modhien D. P. Mason E. Momoniat 《Journal of Applied Mathematics and Physics》 2021年第8期2114-2151,共38页
The two-dimensional spreading under gravity of a thin fluid film with suction (fluid leak-off) or blowing (fluid injection) at the base is considered. The thin fluid film approximation is imposed. The height of the th... The two-dimensional spreading under gravity of a thin fluid film with suction (fluid leak-off) or blowing (fluid injection) at the base is considered. The thin fluid film approximation is imposed. The height of the thin film satisfies a nonlinear diffusion equation with a source/sink term. The Lie point symmetries of the nonlinear diffusion equation are derived and exist, which provided the fluid velocity at the base, <em>v<sub>n</sub></em> satisfies a first order linear partial differential equation. The general form has algebraic time dependence while a special case has exponential time dependence. The solution in which <em>v<sub>n</sub></em> is proportional to the height of the thin film is studied. The width of the base always increases with time even for suction while the height decreases with time for sufficiently weak blowing. The streamlines of the fluid flow inside the thin film are plotted by first solving a cubic equation. For sufficiently weak blowing there is a dividing streamline, emanating from the stagnation point on the centre line which separates the fluid flow into two regions, a lower region consisting of rising fluid and dominated by fluid injection at the base and an upper region consisting of descending fluid and dominated by spreading due to gravity. For sufficiently strong blowing the lower region expands to completely fill the whole thin film. 展开更多
关键词 Thin Fluid Film Suction and Blowing Nonlinear Diffusion Equation Lie point symmetry STREAMLINES
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Painlevéanalysis,infinite dimensional symmetry group and symmetry reductions for the(2+1)-dimensional Korteweg-de Vries-Sawada-Kotera-Ramani equation 被引量:1
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作者 Bo Ren Ji Lin Wan-Li Wang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第8期63-68,共6页
The(2+1)-dimensional Korteweg–de Vries–Sawada–Kotera–Ramani(KdVSKR)equation is studied by the singularity structure analysis.It is proven that it admits the Painlevéproperty.The Lie algebras which depend on t... The(2+1)-dimensional Korteweg–de Vries–Sawada–Kotera–Ramani(KdVSKR)equation is studied by the singularity structure analysis.It is proven that it admits the Painlevéproperty.The Lie algebras which depend on three arbitrary functions of time t are obtained by the Lie point symmetry method.It is shown that the KdVSKR equation possesses an infinite-dimensional Kac–Moody–Virasoro symmetry algebra.By selecting first-order polynomials in t,a finite-dimensional subalgebra of physical transformations is studied.The commutation relations of the subalgebra,which have been established by selecting the Laurent polynomials in t,are calculated.This symmetry constitutes a centerless Virasoro algebra which has been widely used in the field of physics.Meanwhile,the similarity reduction solutions of the model are studied by means of the Lie point symmetry theory. 展开更多
关键词 KdVSKR equation Painleve analysis Lie point symmetry Kac-Moody-Virasoro algebra
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Shape evolution and test of the critical-point symmetry X(5) in ^(176)Os
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作者 郝昕 竺礼华 +9 位作者 吴晓光 李广生 潘波 王烈林 郑云 汪雷 李雪琴 刘颖 丁怀博 李忠宇 《Chinese Physics C》 SCIE CAS CSCD 2009年第S1期151-153,共3页
The lifetimes of excited states in the yrast band of 176Os have been measured up to I = 20 level using the Doppler shift attenuation method. The high-spin states of 176Os were populated via fusion evaporation reaction... The lifetimes of excited states in the yrast band of 176Os have been measured up to I = 20 level using the Doppler shift attenuation method. The high-spin states of 176Os were populated via fusion evaporation reaction 152Sm(28Si,4n)176Os at a beam energy of 140 MeV. The results support an X(5) structure for 176Os at low spin. This structure disappears at high spin and shows a symmetry rotor character. The shape change of 176Os is similar to that of 178Os. 展开更多
关键词 shape evolution critical point symmetry LIFETIME
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Potential Symmetries to a System of Three-Component Nonlinear Diffusion Equations
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作者 XUE Chun-Rong QU Chang-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期193-198,共6页
A system of nonlinear diffusion equations with three components is studied via the potential symmetry method. It is shown that the system admits the potential symmetries for certain diffusion terms. The invariant solu... A system of nonlinear diffusion equations with three components is studied via the potential symmetry method. It is shown that the system admits the potential symmetries for certain diffusion terms. The invariant solutions assoeiated with the potential symmetries are obtained. 展开更多
关键词 Lie point symmetry potential symmetry nonlinear diffusion equation group-invariant solutions
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Luminescence Centers in BaFCl:Ce^(3+) and BaFCl:Gd^(3+) Crystals
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作者 Su Mianzeng and Liao Chunshen (Department of Chemistry, Beijing University, Beijing) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第4期394-398,共5页
Introduction In BaFCl crystal which is of PbFCl type structure in tetragonal system, Ba;ions situate at sites of C;point symmetry, while F;and Cl;ions occupy sites of D;and C;symmetry, respectively. The rare earth ion... Introduction In BaFCl crystal which is of PbFCl type structure in tetragonal system, Ba;ions situate at sites of C;point symmetry, while F;and Cl;ions occupy sites of D;and C;symmetry, respectively. The rare earth ions RE;doped in BaFCl should randomly replace the sites of Ba;ions, and their extra positive charges may be compensated by 展开更多
关键词 Luminescence center Rare earth ions point symmetry
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Time-fractional Davey–Stewartson equation:Lie point symmetries,similarity reductions,conservation laws and traveling wave solutions
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作者 Baoyong Guo Yong Fang Huanhe Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2023年第10期10-25,共16页
As a celebrated nonlinear water wave equation,the Davey–Stewartson equation is widely studied by researchers,especially in the field of mathematical physics.On the basis of the Riemann–Liouville fractional derivativ... As a celebrated nonlinear water wave equation,the Davey–Stewartson equation is widely studied by researchers,especially in the field of mathematical physics.On the basis of the Riemann–Liouville fractional derivative,the time-fractional Davey–Stewartson equation is investigated in this paper.By application of the Lie symmetry analysis approach,the Lie point symmetries and symmetry groups are obtained.At the same time,the similarity reductions are derived.Furthermore,the equation is converted to a system of fractional partial differential equations and a system of fractional ordinary differential equations in the sense of Riemann–Liouville fractional derivative.By virtue of the symmetry corresponding to the scalar transformation,the equation is converted to a system of fractional ordinary differential equations in the sense of Erdélyi–Kober fractional integro-differential operators.By using Noether’s theorem and Ibragimov’s new conservation theorem,the conserved vectors and the conservation laws are derived.Finally,the traveling wave solutions are achieved and plotted. 展开更多
关键词 time-fractional Davey–Stewartson equation Lie symmetry analysis approach Lie point symmetries similarity reductions conservation laws
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Lie Symmetries of Klein-Gordon and Schrodinger Equations
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作者 Muhammad Iqbal Yufeng Zhang 《Applied Mathematics》 2018年第3期336-346,共11页
In this paper, we investigate the Lie point symmetries of Klein-Gordon equation and Schr?dinger equation by applying the geometric concept of Noether point symmetries for the below defined Lagrangian. Moreover, we org... In this paper, we investigate the Lie point symmetries of Klein-Gordon equation and Schr?dinger equation by applying the geometric concept of Noether point symmetries for the below defined Lagrangian. Moreover, we organize a strong relationship among the Lie symmetries related to Klein-Gordon as well as Schr?dinger equations. Finally, we utilize the consequences of Lie point symmetries of Poisson and heat equations within Riemannian space to conclude the Lie point symmetries of Klein-Gordon equation and Schr?dinger equation within universal Riemannian space. 展开更多
关键词 Lie symmetries of Klein-Gordon Equation Lie Symmetries of Schrodinger Equation Noether point Symmetries Of Conformal Lagrangian sl(2 R)Algebra Oscillator System
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