检索结果-南通市图书馆

Two New Types of Conserved Quantities of Mei Symmetry for Holonomic Mechanical System

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第1期49卷 53-56页

作者： fang Jian-hui wang Peng DING Ning College of Physics Science and Technology China University of Petroleum Dongying 257061 China

Two new types of conserved quantities directly deduced by Mei symmetry of holonomic mechanical system are studied. The definition and criterion of Mei symmetry for holonomic system are given. A coordination function is introduced, the conditions under which the Mei symmetry can directly lead to the two types of conserved quantities and the forms of the two types of conserved quantities are obtained. An illustrative example is given. The result indicates that the coordination function can be selected properly according to the demand of the gauge function, thereby the gauge function can be found out more easily. Furthermore, since the choice of the coordination function has multiformity, much T more conserved quantity of Mei symmetry for holonomic mechanical system can be obtained.

关键词： holonomic mechanical system Mei symmetry new conserved quantity

Perturbation and Adiabatic Invariants of Mei Symmetry for Nonholonomic Mechanical Systems

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2007年第4期47卷 594-596页

作者： DING Ning fang Jian-hui wang Peng College of Physical Science and Technology China University of Petroleum Dongying 257061 China

Based on the concept of adiabatic invariant, the perturbation and adiabatic invariants of the Mei symmetry for nonholonomic mechanical systems are studied. The exact invariants of the Mei symmetry for the system without perturbation are given. The perturbation to the Mei symmetry is discussed and the adiabatic invariants of the Mei symmetry for the perturbed system are obtained.

关键词： Mei symmetry perturbation adiabatic invariant nonholonomic mechanical system

Non-Noether Conserved Quantity of Poincaré-Chetaev Equations of a Generalized Classical Mechanics

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2006年第6期45卷 961-964页

作者： ZHANG Peng-Yu fang Jian-hui wang Peng DING Ning College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In the present paper the Lie symmetrical non-Noether conserved quantity of the Poincaré Chetaev equations of a generalized classical mechanics under the general infinitesimal transformations of Lie groups is discussed. First, we establish the determining equations of Lie symmetry of the equations. Second, the Lie symmetrical non-Noether conserved quantity of the equations is deduced. Finally, an example is given to illustrate the application of the results.

关键词： Poincaré-Chetaev equations generalized classical mechanics Lie symmetry non-Noether conserved quantity

Perturbation to Lie Symmetry and Lutzky Adiabatic Invariants for Lagrange Systems

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第1期49卷 57-60页

作者： DING Ning fang Jian-hui wang Peng ZHANG Xiao-Ni College of Physics Science and Technology China University of Petroleum Dongying 2570617 China

Based on the concept of adiabatic invariant, perturbation to Lie symmetry and Lutzky adiabatic invariants for Lagrange systems are studied by using different methods from those of previous works. Exact invariants induced from Lie symmetry of the system without perturbation are given. Perturbation to Lie symmetry is discussed and Lutzky adiabatic invariants of the system subject to perturbation are obtained.

关键词： symmetry perturbation Lutzky adiabatic invariant Lagrange system

A New Type of Conserved Quantity of Mei Symmetry for Lagrange Systems

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2007年第5X期48卷 799-800页

作者： DING Ning fang Jian-hui wang Peng ZHANG Xiao-Ni College of Physics Science and Technology China University of Petroleum Dongying 257061 China

A new type of conserved quantity, which is induced from the Mei symmetry of Lagrange systems, is studied. The conditions for that the new type of conserved quantity exists and the form of the new type of conserved quantity are obtained. An illustrated example is given. The Noether conserved quantity induced from the Mei symmetry of Lagrange systems is a special case of the new type of conserved quantity given in this paper.

关键词： Mei symmetry new type of conserved quantity Lagrange system

Noether-Lie Symmetry of Generalized Classical Mechanical Systems

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第2期49卷 305-307页

作者： ZHANG Xiao-Ni fang Jian-hui wang Peng DING Ning College of Physics Science and Technology China University of Petroleum Dongying 257061. China

In this paper, the Noether Lie symmetry and conserved quantities of generalized classical mechanical system are studied. The definition and the criterion of the Noether Lie symmetry for the system under the general infinitesimal transformations of groups are given. The Noether conserved quantity and the Hojman conserved quantity deduced from the Noether Lie symmetry are obtained. An example is given to illustrate the application of the results.

关键词： generalized classical mechanical system Noether-Lie symmetry Noether conserved quantity Hojman conserved quantity

Classical-field description of Bose-Einstein condensation of parallel light in a nonlinear optical cavity

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2021年第11期30卷 185-195页

作者： hui-fang wang Jin-Jun Zhang Jian-Jun Zhang School of Chemistry and Material Science Shanxi Normal UniversityLinfen 041004China School of Physics and Information Science Shanxi Normal UniversityLinfen 041004China

We study the Bose–Einstein condensation of parallel light in a two-dimensional nonlinear optical cavity,where the massive photons are converted into photon molecules(p-molecules).We extend the classical-field method to provide a description of the two-component system,and we also derive a coupled density equation which can be used to describe the conversion relation between photons and ***,we obtain the chemical potential of the system,and we also find that the system can transform from the mixed photon and p-molecule condensate phase into a pure p-molecule condensate ***,we investigate the collective excitation of the *** also discuss the problem how the spontaneous decay of an atom is influenced by both the phase transition and collective excitation of the coupling system.

关键词： parallel light Bose-Einstein condensation quantum phase transition collective excitation

Enhanced second harmonic generation in a two-dimensional optical micro-cavity

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2018年第3期27卷 286-290页

作者： Jian-Jun Zhang hui-fang wang Jun-Hua Hou School of Physics and Information Science Shanxi Normal University Linfen 041004 China

We introduce a two-dimensional Bose-Einstein condensation model consisting of massive photon and photon-pair. Based on the new nonlinear model, the traditional process of second harmonics generation is reinvestigated. In order to describe the process, a new quantum phase, the harmonic phase, is introduced. The order parameter of the new physical phase is also given in this paper.

关键词： Bose-Einstein condensation quantum phase transition photon

An error recognition method for power equipment defect records based on knowledge graph technology

在线全文

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2019年第11期20卷 1564-1577页

作者： hui-fang wang Zi-quan LIU College of Electrical Engineering Zhejiang UniversityHangzhou 310027China

To recognize errors in the power equipment defect records in real time, we propose an error recognition method based on knowledge graph technology. According to the characteristics of power equipment defect records, a method for constructing a knowledge graph of power equipment defects is presented. Then, a graph search algorithm is employed to recognize different kinds of errors in defect records, based on the knowledge graph of power equipment defects. Finally, an error recognition example in terms of transformer defect records is given, by comparing the precision, recall, F1-score, accuracy, and efficiency of the proposed method with those of machine learning methods, and the factors influencing the error recognition effects of various methods are analyzed. Results show that the proposed method performs better in error recognition of defect records than machine learning methods, and can satisfy real-time requirements.

关键词： Error recognition Power equipment defect record Knowledge graph Machine learning