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Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents
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作者 Yanjing Cao Chenchen Xu +2 位作者 Qi Li Shan Lu Jing Xiao 《International Journal of Mental Health Promotion》 2024年第4期261-269,共9页
Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of thes... Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of these measures over time remains understudied.This research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese teenagers.Method:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D assessment.After a three-month interval,967 of these participants repeated the CES-D evaluation.The study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural integrity.We investigated factorial invariance by conducting a twopronged CFA:one comparing urban vs.rural backgrounds,and another contrasting the results from the initial assessment with those from the follow-up.Results:The CES-D demonstrated adequate reliability in both rural and urban high school student samples.The preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected data.Invariance tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s invariance.Conclusions:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese adolescents.Its applicability is consistent across different living environments and remains stable over time. 展开更多
关键词 DEPRESSION factor structure measurement invariance Chinese adolescent longitudinal invariance
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Novel camera calibration method based on invariance of collinear points and pole-polar constraint
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作者 WEI Liang ZHANG Guiyang +1 位作者 HUO Ju XUE Muyao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期744-753,共10页
To address the eccentric error of circular marks in camera calibration,a circle location method based on the invariance of collinear points and pole–polar constraint is proposed in this paper.Firstly,the centers of t... To address the eccentric error of circular marks in camera calibration,a circle location method based on the invariance of collinear points and pole–polar constraint is proposed in this paper.Firstly,the centers of the ellipses are extracted,and the real concentric circle center projection equation is established by exploiting the cross ratio invariance of the collinear points.Subsequently,since the infinite lines passing through the centers of the marks are parallel,the other center projection coordinates are expressed as the solution problem of linear equations.The problem of projection deviation caused by using the center of the ellipse as the real circle center projection is addressed,and the results are utilized as the true image points to achieve the high precision camera calibration.As demonstrated by the simulations and practical experiments,the proposed method performs a better location and calibration performance by achieving the actual center projection of circular marks.The relevant results confirm the precision and robustness of the proposed approach. 展开更多
关键词 camera calibration cross ratio invariance infinite lines eccentricity error compensate
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Factor Structure and Measurement Invariance of the Japanese Version of the Mother-to-Infant Bonding Scale
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作者 Mami Yamamoto Fumie Takauma +2 位作者 Katsuhiko Tada Kaori Baba Toshinori Kitamura 《Advances in Reproductive Sciences》 2023年第4期159-170,共12页
Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeat... Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeated use of a questionnaire has problems of reduced validity. In order to correctly detect bonding disorders at multiple time points, it is necessary to confirm the measurement invariance of the scale. Baba et al. reported that invariance of the MIBS-J factor structure could only be obtained by abridging the scale into three items. Purpose: The aim of this study was to 1) confirm the factor structure and measurement invariance of the MIBS-J between two measurement times and 2) to examine factors that can be used without being affected by measurement time in order to identify item that contribute to measure met invariance. Methods: We analysed the data of 1049 and 878 mothers with a neonate collected in two waves: 5 days (Wave 1) and 1 month postpartum (Wave 2). Exploratory and confirmatory factor analyses were conducted on the data randomly divided into two groups in each wave. Results: The three-item model (MIBS-J items 1, 6, and 8) was most accepted. Measurement invariance and structural invariance were confirmed in the model. This was consistent with Baba et al.’s model. Conclusion: The three MIBS-J items showed measurement invariance and structural invariance in Japanese mothers during 1 month postpartum. 展开更多
关键词 Bonding Disorders Mother-to-Infant Bonding Scale Factor Analysis Measurement invariance
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Constraining Lorentz Invariance Violation Using Short Gamma-Ray Bursts
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作者 Walid Jamil Azzam Ali Mohamed Hasan 《Journal of Applied Mathematics and Physics》 2023年第8期2179-2184,共6页
Lorentz Invariance is a foundational principle in modern physics, but some recent quantum gravity theories have hinted that it may be violated at extremely high energies. Gamma-ray bursts (GRBs) provide a promising to... Lorentz Invariance is a foundational principle in modern physics, but some recent quantum gravity theories have hinted that it may be violated at extremely high energies. Gamma-ray bursts (GRBs) provide a promising tool for checking and constraining any deviations from Lorentz Invariance due to their huge energies and cosmological distances. Gamma-ray bursts, which are the most intense and powerful explosions in the universe, are traditionally divided into long bursts whose observed duration exceeds 2 s, and short bursts whose observed duration is less than 2 s. In this study, we employ a recent sample of 46 short GRBs to check for any deviation from Lorentz Invariance. We analyze the spectral lag of the bursts in our data sample and check for any redshift dependence in the GRB rest frame, which would indicate a violation of Lorentz Invariance. Our results are consistent, to within 1σ, with no deviation from Lorentz Invariance. 展开更多
关键词 Lorentz invariance Violation Gamma-Ray Bursts Quantum Gravity
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Constructing Hopf Insulator from Geometric Perspective of Hopf Invariant
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作者 常治文 郝维昌 +1 位作者 Miguel Bustamante 刘鑫 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期121-126,共6页
We propose a method to construct Hopf insulators based on the study of topological defects from the geometric perspective of Hopf invariant I.Firstly,we prove two types of topological defects naturally inhering in the... We propose a method to construct Hopf insulators based on the study of topological defects from the geometric perspective of Hopf invariant I.Firstly,we prove two types of topological defects naturally inhering in the inner differential structure of the Hopf mapping.One type is the four-dimensional point defects. 展开更多
关键词 HOPF TOPOLOGICAL invariANT
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A FORM INVARIANCE OF CONSTRAINED BIRKHOFFIAN SYSTEM 被引量:1
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作者 陈向炜 罗绍凯 梅凤翔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第1期53-57,共5页
The form invariance of constrained Birkhoffian system is a kind of invariance of the constrained Birkhoffian equations under infinitesimal transformations. The definition and criteria of the form invariance of constra... The form invariance of constrained Birkhoffian system is a kind of invariance of the constrained Birkhoffian equations under infinitesimal transformations. The definition and criteria of the form invariance of constrained Birkhoffian system are given, and the relation of the form invariance and the Noether symmetry is studied. 展开更多
关键词 CONSTRAINED BIRKHOFFIAN system FORM invariance NOETHER SYMMETRY
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Adaptive Attitude Control for a Coaxial Tilt-Rotor UAV via Immersion and Invariance Methodology 被引量:3
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作者 Longlong Chen Zongyang Lv +2 位作者 Xiangyu Shen Yuhu Wu Xi-Ming Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第9期1710-1713,共4页
Dear Editor,This letter is concerned with the attitude control for a novel tiltrotor unmanned aerial vehicle with two pairs of tiltable coaxial rotors and one rear rotor.An immersion and invariance-based adaptive atti... Dear Editor,This letter is concerned with the attitude control for a novel tiltrotor unmanned aerial vehicle with two pairs of tiltable coaxial rotors and one rear rotor.An immersion and invariance-based adaptive attitude controller for the tilt-rotor unmanned aerial vehicle is proposed.In the proposed control strategy,an adaptive update law is specially designed to compensate for the uncertainties of damping coefficients.The stability of the resulting closed-loop coaxial tiltrotor unmanned aerial vehicle(CTRUAV)system is proved by the Lyapunov methodology and LaSalle’s invariance theory.Finally。 展开更多
关键词 theory. invariance LETTER
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A New Discriminating Experiment on the Invariance Hypothesis of Light Speed 被引量:1
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作者 Jinxi Dong (Beijing Petrochemical College, Daxing, Beijing 102600, People’s Repulic of China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期137-146,共10页
This thesis puts forward a conjecture that, owing to some unknown special character of light, it is impossible to determine whether the speed of light is variable by the interference method. To verify the hypothesis o... This thesis puts forward a conjecture that, owing to some unknown special character of light, it is impossible to determine whether the speed of light is variable by the interference method. To verify the hypothesis of the invariance of light speed, a new method must be found to take accurate measurement of the infinitesimal change in the travelling time of light. The thesis suggests the adoption of high frequency laser pulse technology to carry out the measurement. On the basis of this idea a new discriminating experiment is proposed to test the hypothesis of the invariance of light speed. The thesis also makes some forecast of the future prospects of this experiment and of the future development of the theory of special relativity. 展开更多
关键词 invariance of the SPEED of LIGHT LIGHT pulse method CONJECTURE Discriminating experiment.
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Loop Peeling Based on Quasi-Invariance/Induction Variables 被引量:1
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作者 Litong Song, Robert Glück, Yoshihiko Futamura Institute for Software Production Technology, Waseda University, Okubo 3 4 1, Shinjuku ku Tokyo 169 8555, Japan 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期362-367,共6页
Loop optimization plays an important role in compiler optimization and program transformation. Many sophisticated techniques such as loop invariance code motion have been developed. Loop peeling is a technique to assi... Loop optimization plays an important role in compiler optimization and program transformation. Many sophisticated techniques such as loop invariance code motion have been developed. Loop peeling is a technique to assist parallelization of loops by unfolding loops a few times. This paper introduces a novel technique called loop peeling based on quasi invariance/induction variables. It aims at finding a general and automatic method to derive how many times a given loop should be peeled. Our technique allows for a number of iterations before some variables assigned inside a given loop become invariance or induction variables. In this paper we define the notion of quasi invariance/induction variables, present an algorithm for statically computing the optimal peeling length of a given loop. Our technique can increase the accuracy of program analyses, improve the effectiveness of loop peeling and is well suited as supporting other optimization techniques in the context of supercomputers. 展开更多
关键词 LOOP PEELING PARALLELIZATION INDUCTION VARIABLES QUASI INDUCTION VARIABLES QUASI invariance VARIABLES
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MULTI-INVARIANCE ESPRIT-LIKE ALGORITHMS FOR COHERENT DOA ESTIMATION 被引量:2
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作者 Zhang Xiaofei Xu Dazhuan 《Journal of Electronics(China)》 2010年第1期24-28,共5页
Estimation of Signal Parameters via Rotational Invariance Technique(ESPRIT) algorithm can estimate Direction-Of-Arrival(DOA) of coherent signal,but its performance can not reach full satisfaction.We reconstruct the re... Estimation of Signal Parameters via Rotational Invariance Technique(ESPRIT) algorithm can estimate Direction-Of-Arrival(DOA) of coherent signal,but its performance can not reach full satisfaction.We reconstruct the received signal to form data model with multi-invariance property,and multi-invariance ESPRIT algorithm for coherent DOA estimation is proposed in this paper.The proposed algorithm can resolve the DOAs of coherent signals and performs better in DOA estimation than that of ESPRIT-like algorithm.Meanwhile,it identifies more DOAs than ESPRIT-like algorithm.The simulation results demonstrate its validity. 展开更多
关键词 Coherent signals Direction-Of-Arrival(DOA) estimation Multi-invariance Estimation of Signal Parameters via Rotational invariance Technique(ESPRIT)
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Form Invariance and Noether Symmetries of Rotational Relativistic Birkhoff Systems 被引量:2
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作者 LUO Shao-Kai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第9期257-260,共4页
Under the infinitesimal transformations of groups, a form invariance of rotational relativistic Birkhoffsystems is studied and the definition and criteria are given. In view of the invariance of rotational relativisti... Under the infinitesimal transformations of groups, a form invariance of rotational relativistic Birkhoffsystems is studied and the definition and criteria are given. In view of the invariance of rotational relativistic PfaffBirkhoff D'Alcmbert principle under the infinitesimal transformations of groups, the theory of Noether symmetries ofrotational relativistic Birkhoff systems are constructed. The relation between the form invariance and the Noethersymmetries is studied, and the conserved quantities of rotational relativistic Birkhoff systems are obtained. 展开更多
关键词 ROTATIONAL relativity BIRKHOFF system form invariance NOETHER symmetry CONSERVED quantity
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Measurement invariance and latent mean differences of the Chinese version physical activity self-efficacy scale across gender and education levels 被引量:1
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作者 Han Chen Jun Dai Yong Gao 《Journal of Sport and Health Science》 SCIE 2019年第1期46-54,共9页
Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has... Background: Self-efficacy has been identified as an important determinant of youth's behavior change including physical activity(PA) participation. However, the dimensionality check of a PA self-efficacy scale has rarely been conducted in China. The current study aims to examine(1) the unidimensionality of a shortened Chinese version of PA self-efficacy scale(S-PASESC);(2) the measurement invariance of S-PASESC across gender and levels of education;(3) the latent factor mean difference between gender and levels of education;(4) the direct effects of self-efficacy on PA by different gender and education levels; and(5) the comparisons of the direct effects of self-efficacy on PA across gender and education levels.Methods: The participants were 5 th through 11 th grade public school students recruited from 7 cities located in different geographic regions of China. The final data include a total of 3003 participants(49.7% boys) who have completed the scales.Results: Confirmatory factor analysis(CFA) test supported the unidimensionality of S-PASESC. The S-PASESC is invariant across gender and 3 levels of education at both configural, full metric, and full scalar levels. Findings from latent mean comparisons showed that boys reported higher PA self-efficacy than girls. Students' perceived PA self-efficacy tend to decrease from elementary to high school. Finally, self-efficacy positively related to PA by groups of different gender and education levels and the relationship between self-efficacy and PA is stronger among middle school boys than girls.Conclusion: Findings suggest S-PASESC is a valid scale for measuring Chinese students' PA self-efficacy. 展开更多
关键词 Chinese adolescents Education levels Factor analysis GENDER LATENT mean comparison MEASUREMENT invariance Physical activity SELF-EFFICACY scale
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Identity for the Exponential-Type Molecule Potentials and the Supersymmetry Shape Invariance 被引量:1
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作者 JIA Chun-Sheng ZHANG Ying ZENG Xiang-Lin SUN Liang-Tian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第12期641-646,共6页
The identity and the supersymmetry shape invariance for a class of exponential-type molecule potentials are studied by introducing a deformed five-parameter exponential-type potential (DFPEP) and via the multi-paramet... The identity and the supersymmetry shape invariance for a class of exponential-type molecule potentials are studied by introducing a deformed five-parameter exponential-type potential (DFPEP) and via the multi-parameter deformations. It has been shown that the DFPEP is a shape-invariant potential with a translation of parameters. By making use of the shape invariance approach, the exact energy levels are determined for the bound states with zero angular momentum. A class of molecule potentials and their exact energy spectra for the zero angular momentum states are reduced from the DFPEP and a general energy spectrum formula, respectively. The interrelations for some molecule potentials are also discussed. 展开更多
关键词 DEFORMED five-parameter exponential-type potential shape invariance MULTI-PARAMETER deforma tion energy EIGENVALUE
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A note on the Galilean invariance of aerodynamic force theories in unsteady incompressible flows 被引量:1
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作者 An-Kang Gao Jiezhi Wu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第6期1150-1154,共5页
As a basic principle in classical mechanics,the Galilean invariance states that the force is the same in all inertial frames of reference.But this principle has not been properly addressed by most unsteady aerodynamic... As a basic principle in classical mechanics,the Galilean invariance states that the force is the same in all inertial frames of reference.But this principle has not been properly addressed by most unsteady aerodynamic force theories,if the partial force contributed by a local flow structure is to be evaluated.In this note,we discuss the Galilean-invariance conditions of the partial force for several typical theories and numerically test what would happen if these conditions do not hold. 展开更多
关键词 Galilean invariance Aerodynamic force theory Unsteady flow Flow diagnoses
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Conformal invariance and Noether symmetry, Lie symmetry of holonomic mechanical systems in event space 被引量:5
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作者 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4636-4642,共7页
This paper is devoted to studying the conformal invariance and Noether symmetry and Lie symmetry of a holonomic mechanical system in event space.The definition of the conformal invariance and the corresponding conform... This paper is devoted to studying the conformal invariance and Noether symmetry and Lie symmetry of a holonomic mechanical system in event space.The definition of the conformal invariance and the corresponding conformal factors of the holonomic system in event space are given.By investigating the relation between the conformal invariance and the Noether symmetry and the Lie symmetry,expressions of conformal factors of the system under these circumstances are obtained,and the Noether conserved quantity and the Hojman conserved quantity directly derived from the conformal invariance are given.Two examples are given to illustrate the application of the results. 展开更多
关键词 NOETHER对称性 约束机械系统 共形不变性 事件空间 对称空间 HOJMAN守恒量 LIE对称性 完整系统
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Conformal invariance and integration of first-order differential equations 被引量:7
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作者 何光 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2764-2766,共3页
This paper studies a conformal invariance and an integration of first-order differential equations. It obtains the corresponding infinitesimal generators of conformal invariance by using the symmetry of the differenti... This paper studies a conformal invariance and an integration of first-order differential equations. It obtains the corresponding infinitesimal generators of conformal invariance by using the symmetry of the differential equations, and expresses the differential equations by the equations of a Birkhoff system or a generalized Birkhoff system. If the infinitesimal generators are those of a Noether symmetry, the conserved quantity can be obtained by using the Noether theory of the Birkhoff system or the generalized Birkhoff system. 展开更多
关键词 微分方程 保形不变式 NOETHER理论 积分法
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Conformal invariance and conserved quantity of Hamilton systems 被引量:6
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作者 蔡建乐 罗绍凯 梅凤翔 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3170-3174,共5页
This paper studies conformal invariance and conserved quantities of Hamilton system.The definition and the determining equation of conformal invariance for Hamilton system are provided.The relationship between the con... This paper studies conformal invariance and conserved quantities of Hamilton system.The definition and the determining equation of conformal invariance for Hamilton system are provided.The relationship between the conformal invariance and the Lie symmetry are discussed,and the necessary and sufficient condition that the conformal invariance would be the Lie symmetry of the system under the infinitesimal one-parameter transformation group is deduced.It gives the conserved quantities of the system and an example for illustration. 展开更多
关键词 等角不变性 汉密尔顿体系 决定方程 极小量
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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 gi... 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 共形不变性 动力学系统 相对运动 守恒量 无限小变换 LIE对称性 充分条件
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A conformal invariance for generalized Birkhoff equations 被引量:8
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作者 Fengxiang Mei Jiafang Xie Tieqiang Gang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2008年第5期583-585,共3页
在这篇文章,概括了 Birkhoff 方程被把增补术语加到 Birkhoff 方程提出。Birkhoff 方程的保角的不变性能被用来学习概括 Birkhoff 方程,并且二个例子被举说明结果的申请。
关键词 方程式 共型不变性 对称性 物理
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Form invariance and new conserved quantity of generalised Birkhoffian system 被引量:3
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作者 梅凤翔 吴惠彬 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期31-34,共4页
A form invariance and a conserved quantity of the generalised Birkhoffian system are studied.First,a definition and a criterion of the form invariance are given.Secondly,through the form invariance,a new conserved qua... A form invariance and a conserved quantity of the generalised Birkhoffian system are studied.First,a definition and a criterion of the form invariance are given.Secondly,through the form invariance,a new conserved quantity can be deduced.Finally,an example is given to illustrate the application of the result. 展开更多
关键词 BIRKHOFF系统 形式不变性 守恒量 广义
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