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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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Strong invariance principle for a counterbalanced random walk
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作者 TAN Hui-qun HU Zhi-shui DONG Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期370-380,共11页
We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 wit... We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as follows.For n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n). 展开更多
关键词 random walk MARTINGALE invariance principle
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Form Invariance of Birkhoffian Systems 被引量:4
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作者 梅凤翔 陈向炜 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期138-142,共5页
The form invariance of Birkhoffian systems is a kind of invariance of the Birkhoffian equations under the infinitesimal transformations. The definition and criteria of the form invariance are given, and the relation b... The form invariance of Birkhoffian systems is a kind of invariance of the Birkhoffian equations under the infinitesimal transformations. The definition and criteria of the form invariance are given, and the relation between the form invariance and the Noether symmetry is studied. 展开更多
关键词 Birkhoffian system form invariance Noether symmetry
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Form Invariance of Lagrange System 被引量:57
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作者 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期120-124,共5页
To study a form invariance of Lagrange system, the form invariance of Lagrange equations under the infinitesimal transformations was used. The definition and criterion for the form invariance are given. The relati... To study a form invariance of Lagrange system, the form invariance of Lagrange equations under the infinitesimal transformations was used. The definition and criterion for the form invariance are given. The relation between the form invariance and the Noether symmetry was established. 展开更多
关键词 analytical mechanics Lagrange system form invariance Noether symmetry
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Invariance of Numerical Character of Matrix Products and Their Statistical Applications
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作者 张宝学 张丹松 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期125-130,共6页
To study the invariance of numerical character of matrix products and their statistical applications by matrix theory and linear model theory. Necessary and sufficient conditions are established for the product AB -C... To study the invariance of numerical character of matrix products and their statistical applications by matrix theory and linear model theory. Necessary and sufficient conditions are established for the product AB -C to have its numerical characters invariant with respect to every minimum norm g inverse, respectively. The algebraic results derived are then applied to investigate relationships among BLUE, WLSE and OLSE under the general Gauss? Markoff model. 展开更多
关键词 g inverse range space null space RANK TRACE invariance
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Form Invariance of Routh Equations
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作者 王树勇 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期329-331,共3页
The form invariance of Routh equations in holonomic systems is studied. The definition and criterion for the form invariance under the infinitesimal transformations are given. The relation of the form invariance with ... The form invariance of Routh equations in holonomic systems is studied. The definition and criterion for the form invariance under the infinitesimal transformations are given. The relation of the form invariance with the Noether symmetry and the Lie symmetry is discussed. 展开更多
关键词 analytical mechanics form invariance Noether symmetry Lie symmetry
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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 differential equation conformal invariance Noether theory INTEGRATION
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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
In this article, generalized Birkhoff equations are put forward by adding supplementary terms to the Birkhoff equations. A conformal invariance of the Birkhoff equations can be used to study the generalized Birkhoff E... In this article, generalized Birkhoff equations are put forward by adding supplementary terms to the Birkhoff equations. A conformal invariance of the Birkhoff equations can be used to study the generalized Birkhoff Equations, and two examples are presented to illustrate the application of the results. 展开更多
关键词 Generalized Birkhoff equations Conformal invariance Lie symmetry Noether symmetry
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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 c... 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 Hamilton system conformal invariance determining equation conserved quantity
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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 confor... 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 holonomic system conformal invariance SYMMETRY event space
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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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Lie-form invariance of nonholonomic mechanical systems 被引量:4
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作者 夏丽莉 王静 +1 位作者 后其宝 李元成 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第3期467-469,共3页
The Lie-form invariance of a nonholonomic mechanaical system is studied. The definition and criterion of the Lie-form invariance of the nonholonomic mechaaical system are given. The Hojman conserved quantity and a new... The Lie-form invariance of a nonholonomic mechanaical system is studied. The definition and criterion of the Lie-form invariance of the nonholonomic mechaaical system are given. The Hojman conserved quantity and a new type of conserved quantity are obtained from the Lie-form invariance. An example is givea to illustrate the application of the results. 展开更多
关键词 nonholonomic mechanical systems the Lie-form invariance conserved quantity
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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 conserve... 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 generalised Birkhoffian system form invariance conserved quantity
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Conformal invariance,Noether symmetry,Lie symmetry and conserved quantities of Hamilton systems 被引量:3
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作者 陈蓉 许学军 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期373-377,共5页
In this paper, the relation of the conformal invariance, the Noether symmetry, and the Lie symmetry for the Hamilton system is discussed in detail. The definition of the conformal invariance for Hamilton systems is gi... In this paper, the relation of the conformal invariance, the Noether symmetry, and the Lie symmetry for the Hamilton system is discussed in detail. The definition of the conformal invariance for Hamilton systems is given. The relation between the conformal invariance and the Noether symmetry is discussed, the conformal factors of the determining expressions are found by using the Noether symmetry, and the Noether conserved quantity resulted from the conformal invariance is obtained. The relation between the conformal invariance and the Lie symmetry is discussed, the conformal factors are found by using the Lie symmetry, and the Hojman conserved quantity resulted from the conformal invariance of the system is obtained. Two examples are given to illustrate the application of the results. 展开更多
关键词 Hamilton system conformal invariance conformal factor conserved quantity
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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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Conformal invariance and Hojman conserved quantities for holonomic systems with quasi-coordinates 被引量:2
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作者 罗一平 傅景礼 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期94-99,共6页
We propose a new concept of the conformal invariance and the conserved quantities for holonomic systems with quasi-coordinates. A one-parameter infinitesimal transformation group and its infinitesimal transformation v... We propose a new concept of the conformal invariance and the conserved quantities for holonomic systems with quasi-coordinates. A one-parameter infinitesimal transformation group and its infinitesimal transformation vector of generators for holonomic systems with quasi-coordinates are described in detail. The conformal factor in the determining equations of the Lie symmetry is found. The necessary and sufficient conditions of conformal invariance, which are simultaneously of Lie symmetry, are given. The conformal invariance may lead to corresponding Hojman conserved quantities when the conformal invariance satisfies some conditions. Finally, an illustration example is introduced to demonstrate the application of the result. 展开更多
关键词 quasi-coordinates conformal invariance conformal factor conserved quantity
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Conformal invariance and a kind of Hojman conserved quantity of the Nambu system 被引量:2
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作者 李燕 方建会 张克军 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期9-13,共5页
Conformal invariance and a kind of Hojman conserved quantity of the Nambu system under infinitesimal transformations are studied. The definition and the determining equation of conformal invariance of the system are p... Conformal invariance and a kind of Hojman conserved quantity of the Nambu system under infinitesimal transformations are studied. The definition and the determining equation of conformal invariance of the system are presented. The necessary and sufficient condition under which the conformal invariance of the system would have Lie symmetry under infinitesimal transformations is derived. Then, the condition of existence and a kind of Hojman conserved quantity are obtained. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 conformal invariance Nambu system Hojman conserved quantity
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Conformal invariance and conserved quantities of Appell systems under second-class Mei symmetry 被引量:2
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作者 罗一平 傅景礼 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期100-105,共6页
In this paper we introduce the new concept of the conformal invariance and the conserved quantities for Appell systems under second-class Mei symmetry. The one-parameter infinitesimal transformation group and infinite... In this paper we introduce the new concept of the conformal invariance and the conserved quantities for Appell systems under second-class Mei symmetry. The one-parameter infinitesimal transformation group and infinitesimal transformation vector of generator are described in detail. The conformal factor in the determining equations under second-class Mei symmetry is found. The relationship between Appell system's conformal invariance and Mei symmetry are discussed. And Appell system's conformal invariance under second-class Mei symmetry may lead to corresponding Hojman conserved quantities when the conformal invariance satisfies some conditions. Lastly, an example is provided to illustrate the application of the result. 展开更多
关键词 second-class Mei symmetry conformal invariance conserved quantity Appell system
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Conformal invariance and conserved quantity of third-order Lagrange equations for non-conserved mechanical systems 被引量:2
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作者 张明江 方建会 +2 位作者 路凯 张克军 李燕 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4650-4656,共7页
This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non- conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conf... This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non- conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conformal invariance of the system are presented. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The necessary and sufficient condition that conformal invaxiance of the system would have Lie symmetry under single-parameter infinitesimal transformations is obtained. The corresponding conserved quantity of conformal invariance is derived with the aid of a structure equation. Lastly, an example is given to illustrate the application of the results. 展开更多
关键词 conformal invariance conserved quantity third-order Lagrange equation non-conserved mechanical system
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