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S-rough sets and knowledge separation 被引量:104
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作者 Shi Kaiquan 1,21. School of Mathematics and System Sciences, Liaocheng University, Liaocheng 252059, P. R. China 2. School of Mathematics and System Sciences, Shandong University, Jinan 250100, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期403-410,共8页
The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separ... The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separation are given according to - screen and - screen. 展开更多
关键词 S- rough sets f- screen - screen f-filter theorem - filter theorem knowledge separation.
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Function S-rough sets and law identification 被引量:68
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作者 SHI KaiQuan YAO BingXue 《Science in China(Series F)》 2008年第5期499-510,共12页
By introducing element equivalence class that proposes dynamic characteristic into Pawlak Z rough sets theory, the first author of this paper improved Pawlak Z rough sets and put forward S-rough sets (singular rough ... By introducing element equivalence class that proposes dynamic characteristic into Pawlak Z rough sets theory, the first author of this paper improved Pawlak Z rough sets and put forward S-rough sets (singular rough sets). S-rough sets are defined by element equivalence class that proposes dynamic characteristic. S-rough sets have dynamic characteristic. By introducing the function equivalence class (law equivalence class) that proposes dynamic characteristic into S-rough sets, the first author improved S-rough sets and put forward function S-rough sets (function singular rough sets). Function S-rough sets have dynamic characteristic and law characteristic, and a function is a law. By using function S-rough sets, this paper presents law identification, law identification theorem, and law identification criterion and applications. Function S-rough sets are a new research direction of rough sets theory, and it is also a new tool to the research of system law identification. 展开更多
关键词 function S-rough sets system law law identification identification criterion identification theorem
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The Existence and Multiplicity of Positive Solutions for a Third-order Three-point Boundary Value Problem 被引量:58
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作者 Qing-liu YaoDepartment of Applied Mthematics, Nanjing University of Economics, Nanjing 210003, China 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2003年第1期117-122,共6页
Abstract The existence of n positive solutions for a class of third-order three-point boundary value problems is investigated, where n is an arbitrary natural number. The main tool is Krasnosel'skii fixed point th... Abstract The existence of n positive solutions for a class of third-order three-point boundary value problems is investigated, where n is an arbitrary natural number. The main tool is Krasnosel'skii fixed point theorem on the cone. 展开更多
关键词 Keywords Third-order ordinary differential equation three-point boundary value problem existence of n positive solutions fixed point theorem on cone.
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A CLASS OF NONLOCAL BOUNDARY VALUE PROBLEMS OF NONLINEAR ELLIPTIC SYSTEMS IN UNBOUNDED DOMAINS 被引量:64
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作者 莫嘉琪 欧阳成 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期93-97,共5页
The nonlocal boundary value problems for nonlinear elliptic systems in the unbounded domain are considered. Under suitable conditions the existence of solution and comparison theorem for the boundary value problems ar... The nonlocal boundary value problems for nonlinear elliptic systems in the unbounded domain are considered. Under suitable conditions the existence of solution and comparison theorem for the boundary value problems are studied. 展开更多
关键词 elliptic system boundary value problem comparison theorem
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Survey on normal distributions,central limit theorem,Brownian motion and the related stochastic calculus under sublinear expectations 被引量:54
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作者 PENG ShiGe Institute of Mathematics,Shandong University,Jinan 250100,China 《Science China Mathematics》 SCIE 2009年第7期1391-1411,共21页
This is a survey on normal distributions and the related central limit theorem under sublinear expectation.We also present Brownian motion under sublinear expectations and the related stochastic calculus of It's t... This is a survey on normal distributions and the related central limit theorem under sublinear expectation.We also present Brownian motion under sublinear expectations and the related stochastic calculus of It's type.The results provide new and robust tools for the problem of probability model uncertainty arising in financial risk,statistics and other industrial problems. 展开更多
关键词 probability and distribution uncertainty normal distribution Brownian motion central limit theorem 60H10 60H05 60H30 60E05 60E07 62C05 62D05
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Noether symmetries of the nonconservative and nonholonomic systems on time scales 被引量:54
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作者 CAI PingPing FU JingLi GUO YongXin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第5期1017-1028,共12页
In this paper we give a new method to investigate Noether symmetries and conservation laws of nonconservative and nonholonomic mechanical systems on time scales , which unifies the Noether's theories of the two ca... In this paper we give a new method to investigate Noether symmetries and conservation laws of nonconservative and nonholonomic mechanical systems on time scales , which unifies the Noether's theories of the two cases for the continuous and the discrete nonconservative and nonholonomic systems. Firstly, the exchanging relationships between the isochronous variation and the delta derivatives as well as the relationships between the isochronous variation and the total variation on time scales are obtained. Secondly, using the exchanging relationships, the Hamilton's principle is presented for nonconservative systems with delta derivatives and then the Lagrange equations of the systems are obtained. Thirdly, based on the quasi-invariance of Hamiltonian action of the systems under the infinitesimal transformations with respect to the time and generalized coordinates, the Noether's theorem and the conservation laws for nonconservative systems on time scales are given. Fourthly, the d'Alembert-Lagrange principle with delta derivatives is presented, and the Lagrange equations of nonholonomic systems with delta derivatives are obtained. In addition, the Noether's theorems and the conservation laws for nonholonomic systems on time scales are also obtained. Lastly, we present a new version of Noether's theorems for discrete systems. Several examples are given to illustrate the application of our results. 展开更多
关键词 time scale Lagrange equation delta derivative Noether's theorem nonconservative and nonholonomic system
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Exponential inequalities under the sub-linear expectations with applications to laws of the iterated logarithm 被引量:42
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作者 ZHANG LiXin 《Science China Mathematics》 SCIE CSCD 2016年第12期2503-2526,共24页
Kolmogorov's exponential inequalities are basic tools for studying the strong limit theorems such as the classical laws of the iterated logarithm for both independent and dependent random variables. This paper est... Kolmogorov's exponential inequalities are basic tools for studying the strong limit theorems such as the classical laws of the iterated logarithm for both independent and dependent random variables. This paper establishes the Kolmogorov type exponential inequalities of the partial sums of independent random variables as well as negatively dependent random variables under the sub-linear expectations. As applications of the exponential inequalities, the laws of the iterated logarithm in the sense of non-additive capacities are proved for independent or negatively dependent identically distributed random variables with finite second order moments.For deriving a lower bound of an exponential inequality, a central limit theorem is also proved under the sublinear expectation for random variables with only finite variances. 展开更多
关键词 sub-linear expectation capacity Kolmogorov's exponential inequality negative dependence laws of the iterated logarithm central limit theorem
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THE GROWTH THEOREM FOR STARLIKE MAPPINGS ON BOUNDED STARLIKE CIRCULAR DOMAINS 被引量:39
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作者 LIU TAISHUN (Department of Mathematics, University of Science and Technology of China, Hefei 230026, China)REN GUANGBIN (Department of Mathematics, University of Science and Technology of China, Hefei 230026, China) 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1998年第4期401-408,共8页
The authors obtain the growth and covering theorem for the class of normalized biholomorphic starlike mappings on bounded starlike circular domains.This type of domain discussed is rather general, since the domain mus... The authors obtain the growth and covering theorem for the class of normalized biholomorphic starlike mappings on bounded starlike circular domains.This type of domain discussed is rather general, since the domain must be starlike if there exists a normalized biholomorphic starlike mapping on it. In the unit disc, it is just the famous growth and covering theorem for univalent functions.This theorem successfully realizes the initial idea of H. Cartan about how to extend geometric function theory from one variable to several complex variables. 展开更多
关键词 Starlike mappings Growth theorem Starlike circular domains
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Semi-Fredholm Spectrum and Weyl's Theorem for Operator Matrices 被引量:37
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作者 Xiao Hong CAO Mao Zheng GUO Bin MENG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2006年第1期169-178,共10页
When A ∈ B(H) and B ∈ B(K) are given, we denote by Mc an operator acting on the Hilbert space HΘ K of the form Me = ( A0 CB). In this paper, first we give the necessary and sufficient condition for Mc to be a... When A ∈ B(H) and B ∈ B(K) are given, we denote by Mc an operator acting on the Hilbert space HΘ K of the form Me = ( A0 CB). In this paper, first we give the necessary and sufficient condition for Mc to be an upper semi-Fredholm (lower semi-Fredholm, or Fredholm) operator for some C ∈B(K,H). In addition, let σSF+(A) = {λ ∈ C : A-λI is not an upper semi-Fredholm operator} bc the upper semi-Fredholm spectrum of A ∈ B(H) and let σrsF- (A) = {λ∈ C : A-λI is not a lower semi-Fredholm operator} be the lower semi Fredholm spectrum of A. We show that the passage from σSF±(A) U σSF±(B) to σSF±(Mc) is accomplished by removing certain open subsets of σSF-(A) ∩σSF+ (B) from the former, that is, there is an equality σSF±(A) ∪σSF± (B) = σSF± (Mc) ∪& where L is the union of certain of the holes in σSF±(Mc) which ilappen to be subsets of σSF- (A) A σSF+ (B). Weyl's theorem and Browder's theorem are liable to fail for 2 × 2 operator matrices. In this paper, we also explore how Weyl's theorem, Browder's theorem, a-Weyl's theorem and a-Browder's theorem survive for 2 × 2 upper triangular operator matrices on the Hilbert space. 展开更多
关键词 Semi-Fredholm operator Fredholm operator SPECTRUM Weyl's theorem
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NONLINEAR EXPECTATIONS AND NONLINEAR MARKOV CHAINS 被引量:31
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作者 PENG Shige 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2005年第2期159-184,共26页
This paper deals with nonlinear expectations. The author obtains a nonlinear gen- eralization of the well-known Kolmogorov’s consistent theorem and then use it to con- struct ?ltration-consistent nonlinear expectatio... This paper deals with nonlinear expectations. The author obtains a nonlinear gen- eralization of the well-known Kolmogorov’s consistent theorem and then use it to con- struct ?ltration-consistent nonlinear expectations via nonlinear Markov chains. Com- pared to the author’s previous results, i.e., the theory of g-expectations introduced via BSDE on a probability space, the present framework is not based on a given probabil- ity measure. Many fully nonlinear and singular situations are covered. The induced topology is a natural generalization of Lp-norms and L∞-norm in linear situations. The author also obtains the existence and uniqueness result of BSDE under this new framework and develops a nonlinear type of von Neumann-Morgenstern representation theorem to utilities and present dynamic risk measures. 展开更多
关键词 Backward stochastic differential equations Nonlinear expectation Non-linear expected utilities Measure of risk G-EXPECTATION Nonlinear Mar-kov chain g-martingale Nonlinear martingale Nonlinear Kolmogorov’s consistent theorem Doob-Meyer decomposition
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Existence of Positive Solutions to Second Order Neumann Boundary Value Problems 被引量:31
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作者 蒋达清 刘辉昭 《Journal of Mathematical Research and Exposition》 CSCD 2000年第3期360-364,共5页
The existence of positive solutions to second-order Neumann BVPs -u' + Mu = f(t, u), u'(0) = u'(1) = 0 and u' + Mu = f(t, u), u'(0) =u'(1) is proved by a simple application of a Fixed Poin... The existence of positive solutions to second-order Neumann BVPs -u' + Mu = f(t, u), u'(0) = u'(1) = 0 and u' + Mu = f(t, u), u'(0) =u'(1) is proved by a simple application of a Fixed Point Theorem in cones due to Krasnoselskii[1,6]. 展开更多
关键词 Neumann BVP positive solutions the fixed point theorem.
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Dynamic Modeling and Motion Simulation for A Winged Hybrid-Driven Underwater Glider 被引量:30
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作者 王树新 孙秀军 +2 位作者 王延辉 武建国 王晓鸣 《China Ocean Engineering》 SCIE EI 2011年第1期97-112,共16页
PETREL, a winged hybrid-driven underwater glider is a novel and practical marine survey platform which combines the features of legacy underwater glider and conventional AUV (autonomous underwater vehicle). It can b... PETREL, a winged hybrid-driven underwater glider is a novel and practical marine survey platform which combines the features of legacy underwater glider and conventional AUV (autonomous underwater vehicle). It can be treated as a multi-rigid-body system with a floating base and a particular hydrodynamic profile. In this paper, theorems on linear and angular momentum are used to establish the dynamic equations of motion of each rigid body and the effect of translational and rotational motion of internal masses on the attitude control are taken into consideration. In addition, due to the unique external shape with fixed wings and deflectable rudders and the dual-drive operation in thrust and glide modes, the approaches of building dynamic model of conventional AUV and hydrodynamic model of submarine are introduced, and the tailored dynamic equations of the hybrid glider are formulated. Moreover, the behaviors of motion in glide and thrust operation are analyzed based on the simulation and the feasibility of the dynamic model is validated by data from lake field trials. 展开更多
关键词 hybrid-driven underwater glider autonomous underwater vehicle dynamic modeling momentum theorem
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On Decomposition Theorem of normalized biholomorphic convex mappings in Reinhardt domains 被引量:30
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作者 张文俊 刘太顺 《Science China Mathematics》 SCIE 2003年第1期94-106,共13页
The construction of normalized biholomorphic convex mappings in the Reinhardt domain $D_p = \{ (z_1 ,z_2 , \cdots ,z_n ) \in \mathbb{C}^n :\left| {z_1 } \right|^{p_1 } + \left| {z_2 } \right|^{p_2 } + \cdots + \left| ... The construction of normalized biholomorphic convex mappings in the Reinhardt domain $D_p = \{ (z_1 ,z_2 , \cdots ,z_n ) \in \mathbb{C}^n :\left| {z_1 } \right|^{p_1 } + \left| {z_2 } \right|^{p_2 } + \cdots + \left| {z_n } \right|^{p_n } < 1\} $ , p j > 2, j = 1,2,?, n) of ? n is discussed. The authors set up a Decomposition Theorem for such mappings. As a special case, it is proved that, for each such mapping f, the first k-terms of the homogeneous expansion of its j-th component f j , j = 1, 2, ?, n, depends only on z j , where k is the number that satisfies k < min {p 1, p 2,?, p n ≤ k + 1. When p1,p2, ... ,pn → ∞ , this derives the Decomposition Theorem of normalized biholomorphic convex mappings in the polydisc which was gotten by T.J. Suffridge in 1970. 展开更多
关键词 Reinhardt domain biholomorphic convex mapping Schwarz Lemma Schwarz Lemma
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量纲分析的基本理论及其应用 被引量:24
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作者 徐婕 詹士昌 田晓岑 《大学物理》 北大核心 2004年第5期54-58,共5页
量纲分析是研究物理问题的重要方法之一.本文在研究量纲分析的基本理论Π定理的基础上,提出了量纲分析矢量空间的待定系数法,并举了一些实例,使量纲分析的应用和推广深入了一步.
关键词 量纲分析 Ⅱ定理 量纲分析矢量空间
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Theory of truth degrees of formulas in Lukasiewicz n-valued propositional logic and a limit theorem 被引量:30
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作者 LI Bijing WANG Guojun 《Science in China(Series F)》 2005年第6期727-736,共10页
The concept of truth degrees of formulas in Lukasiewicz n-valued propositional logic Ln is proposed. A limit theorem is obtained, which says that the truth function τ-n induced by truth degrees converges to the integ... The concept of truth degrees of formulas in Lukasiewicz n-valued propositional logic Ln is proposed. A limit theorem is obtained, which says that the truth function τ-n induced by truth degrees converges to the integrated truth function τ when n converges to infinite. Hence this limit theorem builds a bridge between the discrete valued Lukasiewicz logic and the continuous valued Lukasiewicz logic. Moreover, the results obtained in the present paper is a natural generalization of the corresponding results obtained in two-valued propositional logic. 展开更多
关键词 Lukasiewicz n-valued propositional logic truth degree limit theorem integrated truth degree
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ON THE EXISTENCE OF POSITIVE SOLUTIONS TO SECOND ORDER PERIODIC BVPS 被引量:28
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作者 蒋达清 《Acta Mathematica Scientia》 SCIE CSCD 1998年第S1期31-35,共5页
The existence of positive solutions to second-order periodic BVPs-u'+Mu =j(t, u),t(0) = u(2π),u'(0) = '(2π) and u'+ Mu = I(t, u), u(0) = u(2π), u'(0) = u'(2π)is proved by a simple appliCati... The existence of positive solutions to second-order periodic BVPs-u'+Mu =j(t, u),t(0) = u(2π),u'(0) = '(2π) and u'+ Mu = I(t, u), u(0) = u(2π), u'(0) = u'(2π)is proved by a simple appliCation of a Fixed point Theorem in cones due to Krasnoselskii. 展开更多
关键词 Periodic BVP. positive solutions. the fixed point theorem
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Both-branch fuzzy decision and decision encryptionauthentication 被引量:28
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作者 史开泉 崔玉泉 《Science in China(Series F)》 2003年第2期90-103,共14页
This paper is on fuzzy decision theory and information security theory which are mutually independent and engrafted. This paper presents both-branch fuzzy decision and problems on decision encryption-authentication, p... This paper is on fuzzy decision theory and information security theory which are mutually independent and engrafted. This paper presents both-branch fuzzy decision and problems on decision encryption-authentication, puts forward two kinds of both-branch fuzzy decision on X: both-branch fuzzy decision on X having bounded domains X = X+∩X- ={x0}, both-branch fuzzy decision on X havingoverlapping domains X* = X+∩X- = {x_1~*,x_2~*,…,x_1~*}. It presents single branch separate-separate out theoremof both-branch fuzzy decision on X, single branch superposition theorem of both-branch fuzzy decision, exclusive-decompose principle of both-branch fuzzy decision. This paper presents encryption-authentication theorem of decision by engrafting information security theory and technique with both-branch fuzzy decision, and provides encryption-decryption and signature-authentication of both-branch fuzzy decision. 展开更多
关键词 both-branch fuzzy decision separate-separate out theorem exclusive-decompose principle elliptic curve decision encryption decision authentication.
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Sharp Growth Theorems and Coefficient Bounds for Starlike Mappings in Several Complex Variables 被引量:28
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作者 Hidetaka HAMADA Tatsuhiro HONDA 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2008年第4期353-368,共16页
Let B be the unit ball in a complex Banach space. Let S^*k+1(B) be the family of normalized starlike mappings f on B such that z = 0 is a zero of order k + 1 of f(z) - z. The authors obtain sharp growth and cov... Let B be the unit ball in a complex Banach space. Let S^*k+1(B) be the family of normalized starlike mappings f on B such that z = 0 is a zero of order k + 1 of f(z) - z. The authors obtain sharp growth and covering theorems, as well as sharp coefficient bounds for various subsets of S^*k+1(B). 展开更多
关键词 Sharp coefficient bound Sharp covering theorem Sharp growth theorem Starlike mapping Zero of order k
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Function S-rough sets and mining-discovery of rough law in systems 被引量:25
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作者 Shi Kaiquan Xia Jiarong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期919-926,共8页
Function S-rough sets (function singular rough sets) is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives... Function S-rough sets (function singular rough sets) is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives rough law generation model of a-function equivalence class, discussion on law mining and law discovery in systems, and application of law mining and law discovery in communication system. Function S-rough sets is a new theory and method in law mining research. 展开更多
关键词 function S-rough sets structure of function S-rough sets relationship theorem rough law mining-discovery applications.
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The Noether's Theory of Birkhoffian Systems~* 被引量:27
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作者 梅凤翔 《Science China Mathematics》 SCIE 1993年第12期1456-1467,共12页
By using the generalized quasi-symmetry of the infinitesimal transformation of the transformation group G_r, the Noether’s theory for Birkhoffian systems (including Noether’s theorem and its inverse) has been establ... By using the generalized quasi-symmetry of the infinitesimal transformation of the transformation group G_r, the Noether’s theory for Birkhoffian systems (including Noether’s theorem and its inverse) has been established. An example is given. 展开更多
关键词 CONSERVATION law SYMMETRY PFAFFIAN action BIRKHOFFIAN system Noether’s theorem.
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