基于Pro/E的渐开线直齿圆柱齿轮三维造型设计

根据渐开线的形成原理,给出了渐开线齿形在笛卡尔坐标系和圆柱坐标系中的参数方程。最后详细介绍了在Pro/Engineer wildfire环境下,绘制精确渐开线直齿圆柱齿轮的三维造型方法。     

泛函微分方程收敛解的存在性和存在唯一性定理

本文给出泛函微分方程存在收敛于有限极限的解的充分性条件,在某种意义下,考虑了上述解的唯一性,特别地,我们的结果提供了收敛阶的某些信息。     

Latent Variable Modelling: A Survey*

Abstract. Latent variable modelling has gradually become an integral part of mainstream statistics and is currently used for a multitude of applications in different subject areas. Examples of ‘traditional’ latent variable models include latent class models, item–response models, common factor models, structural equation models, mixed or random effects models and covariate measurement error models. Although latent variables have widely different interpretations in different settings, the models have a very similar mathematical structure. This has been the impetus for the formulation of general modelling frameworks which accommodate a wide range of models. Recent developments include multilevel structural equation models with both continuous and discrete latent variables, multiprocess models and nonlinear latent variable models.     

具正负系数的二阶中立型微分方程解的振动性

本文研究具有正负系数和变偏差的二阶中立型微分方程，建立了方程的所有有界解振动的一个充要条件和一些充分判据．     

一类退化抛物型方程解的有界性

对一类具有很一般结构条件的退化抛物型方程，证明解的有界性，包括局部有界性和整体有界性．     

A note on sequential ML estimates and their asymptotic covariances

A marginal and sequential maximum likelihood estimation method is described which can be used instead of full information maximum likelihood estimation if the latter method is unfeasible. It is shown that the sequential procedure yields strongly consistent and asymptotically normal estimates under relatively general regularity conditions. It is shown that the covariance matrix of the sequential ML estimator does not coincide with the inverse of the Fisher information matrix. Hence, the corrected covariance matrix is derived. The application of the sequential procedure to the multivariate probit model with dichotomous, ordered categorical, single-sided censored and double-sided censored endogenous variables is included. This research was partially supported by a dissertation grant of theStudienstiftung des Deutschen Volkes. Comments and suggestions on earlier drafts by Gerhard Arminger, Giorgio Calzolari, Bernd Kortzen and an anonymous referee are gratefully acknowledged.     

德育环境三维理论模型及其价值

德育环境三维理论模型是指由环境、中介、人的素质三者构成的理论模型。这一理论模型,以马克思主义关于环境的界定和人与环境关系的思想为指导,深刻而简洁地揭示了环境、中介、人的思想道德素质三者之间的内在有机联系。这一模型的理论价值在于揭示了历史唯物主义、德育理论和数理统计三者之间高度的内在统一性。方法价值在于为德育科学研究方法探索出一套将历史方法、德育理论和数理统计方法三者统一起来的具体途径。     

3×3一阶线性微分方程组的积分解法

讨论3×3一阶线性微分方程组的积分解法,并给出其通解公式。     

蜂窝板状材料反平面变形的等效本构方程

用含等效偶应力的极性介质模型讨论蜂窝板状材料的反平面问题,提出含偶应力和应力的等效本构方程。用这个等效本构方程分析一维静力学问题表明,同时忽略应力与扭曲和偶应力与应变的本构联系,可以得到简洁准确的分析结果。     

光热变形理论中热弹性方程的解

利用格林函数法求解了在一定的温度分布条件下无限大平板的准穗态热弹性方程,得到了方程的一个完整,简单的积分形式的解。该表达式可用于激光光热变形和光热光束偏转理论中,以求得被测平板样品的表面变形和表面倾斜度,从而决定被测样品的热物理性质。