基于ANSYS的高速包装机的椭圆齿轮模态分析   总被引：1，自引：1，他引：0  

黄志东  韩杨 《辽宁科技学院学报》2010,12(3):29-30,46

采用有限元法,建立了椭圆齿轮的动力学模型,通过有限元分析软件ANSYS对椭圆齿轮进行模态分析,得到了椭圆齿轮的前六阶固有频率和对应振型。该方法和所得结果为动态设计提供了参考,同时也为椭圆齿轮系统的动态响应计算和分析奠定了基础。  相似文献   

Confidence Intervals for a Semiparametric Approach to Modeling Nonlinear Relations among Latent Variables     

Jolynn Pek  Diane Losardo  Daniel J. Bauer 《Structural equation modeling》2013,20(4):537-553

Compared to parametric models, nonparametric and semiparametric approaches to modeling nonlinearity between latent variables have the advantage of recovering global relationships of unknown functional form. Bauer (2005) Bauer, D. J. 2005. A semiparametric approach to modeling nonlinear relations among latent variables. Structural Equation Modeling, 12: 513–535. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar] proposed an indirect application of finite mixtures of structural equation models where latent components are estimated in the service of more flexibly recovering characteristics of the latent aggregate regression function. This article develops and evaluates delta method and parametric bootstrap approaches for obtaining approximate confidence intervals for Bauer's semiparametric approach to modeling latent nonlinear functions. Coverage rates of these approximate point-wise confidence intervals or nonsimultaneous confidence bands are evaluated by Monte Carlo and recommendations for their use are suggested.  相似文献   

Modeling Ability Differentiation in the Second-Order Factor Model     

Dylan Molenaar  Conor V. Dolan  Han L.J. van der Maas 《Structural equation modeling》2013,20(4):578-594

In this article we present factor models to test for ability differentiation. Ability differentiation predicts that the size of IQ subtest correlations decreases as a function of the general intelligence factor. In the Schmid–Leiman decomposition of the second-order factor model, we model differentiation by introducing heteroscedastic residuals, nonlinear factor loadings, and a skew-normal second-order factor distribution. Using marginal maximum likelihood, we fit this model to Spanish standardization data of the Wechsler Adult Intelligence Scale (3rd ed.) to test the differentiation hypothesis.  相似文献   

Fitting Nonlinear Latent Growth Curve Models With Individually Varying Time Points     

Sonya K. Sterba 《Structural equation modeling》2013,20(4):630-647

Individual growth trajectories of psychological phenomena are often theorized to be nonlinear. Additionally, individuals’ measurement schedules might be unique. In a structural equation framework, latent growth curve model (LGM) applications typically have either (a) modeled nonlinearity assuming some degree of balance in measurement schedules, or (b) accommodated truly individually varying time points, assuming linear growth. This article describes how to fit 4 popular nonlinear LGMs (polynomial, shape-factor, piecewise, and structured latent curve) with truly individually varying time points, via a definition variable approach. The extension is straightforward for certain nonlinear LGMs (e.g., polynomial and structured latent curve) but in the case of shape-factor LGMs requires a reexpression of the model, and in the case of piecewise LGMs requires introduction of a general framework for imparting piecewise structure, along with tools for its automation. All 4 nonlinear LGMs with individually varying time scores are demonstrated using an empirical example on infant weight, and software syntax is provided. The discussion highlights some advantages of modeling nonlinear growth within structural equation versus multilevel frameworks, when time scores individually vary.  相似文献   

Modeling Nonlinear Structural Equation Models: A Comparison of the Two-Stage Generalized Additive Models and the Finite Mixture Structural Equation Model     

W. Holmes Finch 《Structural equation modeling》2013,20(1):60-75

Researchers have devoted some time and effort to developing methods for fitting nonlinear relationships among latent variables. In particular, most of these have focused on correctly modeling interactions between 2 exogenous latent variables, and quadratic relationships between exogenous and endogenous variables. All of these approaches require prespecification of the nonlinearity by the researcher, and are limited to fairly simple nonlinear relationships. Other work has been done using mixture structural equation models (SEMM) in an attempt to fit more complex nonlinear relationships. This study expands on this earlier work by introducing the 2-stage generalized additive model (2SGAM) approach for fitting regression splines in the context of structural equation models. The model is first described and then investigated through the use of simulated data, in which it was compared with the SEMM approach. Results demonstrate that the 2SGAM is an effective tool for fitting a variety of nonlinear relationships between latent variables, and can be easily and accurately extended to models including multiple latent variables. Implications of these results are discussed.  相似文献   

非线性带涂层圆柱形复合介质的电势分布     

郝艳花  张英  乔世东 《雁北师范学院学报》2013,(1):30-33

利用摄动方法,研究了在外加交流电场E=E1sinωt＋E2sin3ωt＋E5sin5ωt的作用下,非线性带涂层圆柱形复合介质的电势分布,这种介质的电流密度J和电场强度E之间满足的关系为Jα=σαE＋χα｜E｜2E。  相似文献   

修正的Volterra格子方程的精确解     

杨立波 《洛阳师范学院学报》2013,(11):9-11

对G'/G展开法进行了扩展,并将该方法应用到非线性差分微分方程的求解领域,通过借助符号计算系统Mathematica,得到了修正的Volterra格子方程的多组含参的新的精确解,包括双曲函数解、三角函数解和有理函数解.  相似文献   

基础-结构耦合系统受地震作用的非线性振动     

杨志安  常文洁  李高峰 《唐山学院学报》2013,26(3):1-4

以基础-结构耦合系统受地震作用的动力学方程为基础,考虑系统的固有特性和地震激励特征,研究基础-结构耦合系统受地震作用的组合共振问题。利用非线性振动的多尺度法,求得系统三频率组合共振的响应曲线,并分别进行数值计算。分析阻尼系数、地基参数、非线性因子和小参数等对共振的影响。计算结果可用于基础一结构耦合系统的动力设计。  相似文献   

受简谐激励载流导线的强非线性主共振     

席晓燕  杨志安  李高峰  朱昌健 《唐山学院学报》2013,26(3):5-7

采用MLP方法研究受简谐激励的载流导线的强非线性振动。根据得到的载流导线强非线性Duffing方程应用MLP方法求得主共振幅频响应方程,并对其进行数值计算,分析电流、张力、激励、几何参数等对强非线性主共振系统的影响。  相似文献   

索伯列夫空间W1,p(D)中的非线性椭圆组的非线性Riemann边值问题     

SONG Jie  LI Ming-Zhong 《上海大学学报(英文版)》2005,9(1)

The nonlinear Riemann problems were converted into nonlinear singular integral equations and the existence of the solution for the problem was proved by means of contract principle.  相似文献