关于已知函数对中间变量的导数求函数的一种方法

本文提出了若干类函数对中间变量的导数,借用微积分的方法,运用变量替换的技巧,找到了求这几类函数的有效方法.给出了所求函数的表达式,其结论是有关文献例题的推广.直接利用所得结论解题,使求解过程大为简化,文中列举了实例.     

化学镀金镀速的研究

研究了以硼氢化物作为还原剂的化学镀金溶液，通过正交实验得出了主盐、还原剂、络合剂、ｐＨ值和温度对镀速影响的关系，对正文实验结果进行线性回归，得出了化学镀金动力学经验方程，并得出最佳配方及工艺条件。     

Non-parametric Maximum-Likelihood Estimation in a Semiparametric Mixture Model for Competing-Risks Data

Abstract.  This paper describes our studies on non-parametric maximum-likelihood estimators in a semiparametric mixture model for competing-risks data, in which proportional hazards models are specified for failure time models conditional on cause and a multinomial model is specified for the marginal distribution of cause conditional on covariates. We provide a verifiable identifiability condition and, based on it, establish an asymptotic profile likelihood theory for this model. We also provide efficient algorithms for the computation of the non-parametric maximum-likelihood estimate and its asymptotic variance. The success of this method is demonstrated in simulation studies and in the analysis of Taiwan severe acute respiratory syndrome data.     

一类两指标Volterra型随机积分方程解的存在性、唯一性

本文利用随机积分压缩函数的方法讨论两指标Volterra—ItO方程 X(Z)=φ(Z)+∫_(R_zK(Z,ξ)f_1(ξ,X(ξ)dξ)+∫_(R_zf_2(ξ,X(ξ))dB(ξ)),Z∈R_+~2其中B(Z)是平面上Win-ner—Yeh过程。在较Lip更一般的条件下,得到解的存在唯一性。     

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.