基于差异系数的多元过程能力指数

过程能力指数表示过程能力满足产品质量标准的程度的评价指标，最普遍使用的过程能力指数有Cp、Cpk、Cpm、Cpkm等，它们已在各大工业部门得到了广泛的应用，但是多元质量特性的过程能力指数尚未得到很好的解决。许多学试图以不同的方式、方法计算多元质量特性的过程能力指数，但存在局限性。本以多元正态分布为基础，比较分析了每个质量特征的差异系数，给出了多元过程能力指数的计算公式。最后的一个算例表明，该方法是有效且符合实际的。  

The Projection onto a Direct Product of Convex Cones

ＴｈｅＰｒｏｊｅｃｔｉｏｎｏｎｔｏａＤｉｒｅｃｔｒｏｄｕｃｔｏｆＣｏｎｖｅｘＣｏｎｅｓＬｉｕＷｅｉ（刘维）ａｎｄＳｈｉＮｉｎｇｚｈｏｎｇ（史宁中）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＮｏｒｔｈｅａｓｔＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｃ...  

二次谐波产生耦合方程组的解

本文讨论了非线性光学中的二次谐波产生的耦合方程组 ,利用变分法证明了耦合方程组非平凡解的存在性 ,然后进行了数值模拟 ,实验结果表明文中方法比经典的非线性光学中的方法有较大的改进 ,这对优化光倍频器件的设计将有所帮助 .  

基于非对称损失的过程均值设计研究

在损失非对称的情况下，使工序加工出的产品均值等于目标值，并不会使期望损失最小，优化过程均值，使其接近目标值，尤为重要。本研究了三种典型的非对称损失的过程均值设计问题，探讨了非对称比率与质量损失率之间的关系，提出了有效偏移的概念，给出了具体的调整措施，最后给出一个实例。  

Attractors and dimension of dissipative lattice systems

In this paper, by using the argument in [Q.F. Ma, S.H. Wang, C.K. Zhong, Necessary and sufficient conditions for the existence of global attractor for semigroup and application, Indiana Univ. Math. J., 51(6) (2002), 1541-1559.], we prove that the condition given in [S. Zhou, Attractors and approximations for lattice dynamical systems, J. Differential Equations 200 (2004) 342-368.] for the existence of a global attractor for the semigroup associated with general lattice systems on a discrete Hilbert space is a sufficient and necessary condition. As an application, we consider the existence of a global attractor for a second-order lattice system in a discrete weighted space containing all bounded sequences. Finally, we show that the global attractor for first-order and partly dissipative lattice systems corresponding to (partly dissipative) reaction-diffusion equations and second-order dissipative lattice systems corresponding to the strongly damped wave equations have finite fractal dimension if the derivative of the nonlinear term is small at the origin.  

A barrier method for dynamic Leontief-type linear programs

In this paper, we specialize Gill et al.'s projected Newton barrier method to solve a large-scale linear program of dynamic (i.e. multistage) Leontief-type constraints. We propose an efficient and stable method for solving the least-squares subproblems, the crucial part of the barrier method. The key step is to exploit a special structure of the constraint matrix and reduce the matrix of the normal equation for the least-squares problem to a banded matrix. By comparing the average-case operations count of this specialized barrier method with that of the sparse simplex method, we show that this method performs at least O(T) faster than the simplex method for such stype of linear programs, where T is the number of time periods (i.e. stages).  

对修理期间部件无老化的串联系统可用度的进一步探讨

一般认为串联系统多部件中至多允许一个部件失效且其他部件服从于统计独立情况.论述了修理期间部件无老化的串联系统分别在统计独立情况下及包含共因失效情况下的稳态可用度,并对给出一般表达式.  

Optimality conditions and duality for a minimax fractional programming with generalized convexity

We establish the sufficient conditions for generalized fractional programming from a viewpoint of the generalized convexity. When the sufficient conditions are utilized, the corresponding duality theorems are derived for two types of duals of the generalized fractional programming. We extend the corresponding results of several authors.  

Cpk写控制图的研究与应用

控制图与过程能力指数Cp(Cpk)都是用来进行质量分析与处理的重要工具。文[1]谈及控制图的两类错误(其概率分别为α、β)，文[2]讨论了Cpk与α的关系，但涉及Cpk与控制图检出力(1-β)关系的文章却不多。本文以又控制图为例，讨论了α、β、1-β、与Cpk的关系，得出了联合应用它们会对工序状态有较好的了解，对其适当的调整有助於提高产品质量。  

Strong Convergence Theorems for Mixed Typ e Asymptotically Nonexpansive Mappings

The purpose of this paper is to study a new two-step iterative scheme with mean errors of mixed type for two asymptotically nonexpansive self-mappings and two asymptotically nonexpansive nonself-mappin...