6σ与ERP中质量管理子系统的集成

ERP是企业管理信息化的代表者,6σ是数据化管理的具体化。将6σ管理的思想理念、统计方法和强大的工具引入到ERP质量管理子系统的六个功能模快设计中,为6σ与ERP的进一步结合与集成研究打下基础。     

6σ管理中需要澄清的几个问题

6σ管理作为组织实施连续质量改进的一种经营策略,已引起企业界和学术界的极大兴趣,并在一些企业中得到很好应用。正确实施6σ,需要对其基本概念、假设条件、相关约束等有一个较为全面的了解和认识。本文探讨了6σ文献和应用过程中需要关注的几个问题,其中包括6σ的基本概念和特点;分布假设;过程均值1.5σ漂移的可行性;过程能力指数;短期波动和长期波动;6σ改进和6σ设计等。     

生产过程标准差估计值的评价和选取—数理分析与模拟验证

一、问题的提出 在工业产品质量的统计控制中,通常用字母σ表示生产过程的标准差;用距加工中心正负三个生产过程的标准差(即6σ)来描述工序能力,表示产品质量特性值约有99.73%集中在此范围内;而产品的技术要求同工序能力之比则称为工序能力指数.当产品质量特性值分布中心规范界     

现代质量管理与6σ流程控制

本文以作者在GE和MOTOROLA服务的体会简要介绍近年来6σ质量管理在全球的应用发展情况。随后对Kσ原则下的过程能力指数及不合格品率作了计算和比较,并对有漂移情况下6σ流程控制作了讨论和评价。     

关于6 Sigma与3 Sigma的比较

在企业推广6σ的过程中,经常有学员不明白为什么6σ比3σ好,甚至有人会说6σ的规格限比3σ的规格限宽,当然6σ的合格率比3σ的合格率高。本文认为文献[1]、[2]关于6σ与3σ的比较图是引起这种误会的根源。为此本文给出另外的比较和解释。     

半参数回归模型的估计的渐近性质

考虑半参数回归模型ｙｉ＝ｘｉ＾１β＋ｇ（ｔｉ）＋ｅｉ,１≤ｉ≤ｎ;其中ｇ为Ｒ上未知函数,σ０＾２＝Ｄ（ｅ１）柴根象等在１９９５年给出了β的二阶段估计βｎ,本文基于β１建立了σ０＾２的估计量σｎ＾２,研究了误差方差估计σｎ＾２的渐近正态性和强相合性,并且得到了可直接用于统计推断的统计量及其分布。     

两个正态总体的似然比检验

对于两个正态总体N（μ1,σ1^2)和N(μ2，σ2^2)，本文讨论了统计假设H0：μ1=μ，σ1^2=σ2^2←→H1：μ1≠μ，或σ1^2≠σ2^2。给出了似然比检验统计量分布及相应的临界值表，并对其临界值表的计算给出了详细的讨论。     

σ,双A,Aσ-统计收敛的表示定理

证明了Banach空间X中序列{x_k},σ-统计收敛以及双序列{x_（kl）},双A和A_σ统计收敛的表示定理.     

关于容度的Fubini定理

Fubini定理是经典概率论和测度论中的一个基本概念,它在多元统计和随机过程中具有重要应用。近年来,在乘积代数和乘积σ-代数上关于容度的Fubini定理已分别被讨论,然而它们还只局限于对切面-共单调函数的特殊情形。本文主要基于一类更广义的既μ1-Choquet可积又μ2-Choquet可积函数研究关于凹(凸)容度的Fubini定理,进而推广了乘积σ-代数上关于容度的Fubini定理。     

统计自相似集和测度的概率特征

证明了统计自相似集和测度是由一族独立同分布的随机压缩算子｛fσ,σ∈D｝所构成的随机递归集和它的分布．此处fσ是概率空间（Ω,F,P）到con（E）的随机元,con（E）是完备可分距离空间E到E的压缩算子全体．     

An inequality unscented transformation for estimating the statistical moments

Point estimate method (PEM) is convenient for estimating statistical moments. This paper focuses on discussing the existing PEMs and presenting a new PEM for the efficient and accurate estimation of statistical moments. Firstly, a classification method of PEMs is proposed based on the strategy of choosing sigma points. Secondly, the minimum number of sigma points and the error of inverse Nataf transformation are derived corresponding to certain order and dimensionality of PEMs. Then the inequality unscented transformation (IUT) is presented to estimate the statistical moments. The proposed IUT permits the existing of limited errors in the matching of the first several order moments to decrease the number of sigma points, it opens new strategy of PEMs. The proposed method has two advantages. The first advantage is overcoming the growth of the number of sigma points with dimensionality since it parameterizes the number of sigma points and accuracy order. The second advantage is the wide applicability, for it has the ability to handle correlated and asymmetric random input variables and to match cross moments. Numerical and engineering results show the good accuracy and efficiency of the proposed IUT.     

Cycles representing the Todd class of a toric variety

In this paper, we describe a way to construct cycles which represent the Todd class of a toric variety. Given a lattice with an inner product, we assign a rational number to each rational polyhedral cone in the lattice, such that for any toric variety with fan in the lattice, we have

This constitutes an improved answer to an old question of Danilov.

In a similar way, beginning from the choice of a complete flag in the lattice, we obtain the cycle Todd classes constructed by Morelli.

Our construction is based on an intersection product on cycles of a simplicial toric variety developed by the second author. Important properties of the construction are established by showing a connection to the canonical representation of the Todd class of a simplicial toric variety as a product of torus-invariant divisors developed by the first author.

     

The Cauchy-Dirichlet problem for the heat equation in Besov spaces

The solvability in anisotropic spaces , σ ∈ ℝ₊, p, q ∈ (1, ∞), of the heat equation u_t − Δu = f in Ω^T ≡ (0, T) × Ω is studied under the boundary and initial conditions u = g on S^T, u|_t=0 = u₀ in Ω, where S is the boundary of a bounded domain Ω ⊂ ℝⁿ. The existence of a unique solution of the above problem is proved under the assumptions that and under some additional conditions on the data. The existence is proved by the technique of regularizers. For this purpose the local-in-space solvability near the boundary and near an interior point of Ω is needed. To show the local-in-space existence, the definition of Besov spaces by the dyadic decomposition of a partition of unity is used. This enables us to get an appropriate estimate in a new and promising way without applying either the potential technique or the resolvent estimates or the interpolation. Bibliography: 26 titles. Published in Zapiski Nauchnykh Seminarov POMI, Vol. 348, 2007, pp. 40–97.     

Deformation of the $$\sigma _2$$-curvature

Our main goal in this work is to deal with results concern to the \(\sigma _2\)-curvature. First we find a symmetric 2-tensor canonically associated to the \(\sigma _2\)-curvature and we present an almost-Schur-type lemma. Using this tensor, we introduce the notion of \(\sigma _2\)-singular space and under a certain hypothesis we prove a rigidity result. Also we deal with the relations between flat metrics and \(\sigma _2\)-curvature. With a suitable condition on the \(\sigma _2\)-curvature, we show that a metric has to be flat if it is close to a flat metric. We conclude this paper by proving that the three-dimensional torus does not admit a metric with constant scalar curvature and nonnegative \(\sigma _2\)-curvature unless it is flat.     

Optimal lower exponent for the higher gradient integrability of solutions to two-phase elliptic equations in two dimensions

We study the higher gradient integrability of distributional solutions u to the equation \({{\mathrm{div}}}(\sigma \nabla u) = 0\) in dimension two, in the case when the essential range of \(\sigma \) consists of only two elliptic matrices, i.e., \(\sigma \in \{\sigma _1, \sigma _2\}\) a.e. in \(\Omega \). In Nesi et al. (Ann Inst H Poincaré Anal Non Linéaire 31(3):615–638, 2014), for every pair of elliptic matrices \(\sigma _1\) and \(\sigma _2\), exponents \(p_{\sigma _1,\sigma _2}\in (2,+\infty )\) and \(q_{\sigma _1,\sigma _2}\in (1,2)\) have been found so that if \(u\in W^{1,q_{\sigma _1,\sigma _2}}(\Omega )\) is solution to the elliptic equation then \(\nabla u\in L^{p_{\sigma _1,\sigma _2}}_{\mathrm{weak}}(\Omega )\) and the optimality of the upper exponent \(p_{\sigma _1,\sigma _2}\) has been proved. In this paper we complement the above result by proving the optimality of the lower exponent \(q_{\sigma _1,\sigma _2}\). Precisely, we show that for every arbitrarily small \(\delta \), one can find a particular microgeometry, i.e., an arrangement of the sets \(\sigma ^{-1}(\sigma _1)\) and \(\sigma ^{-1}(\sigma _2)\), for which there exists a solution u to the corresponding elliptic equation such that \(\nabla u \in L^{q_{\sigma _1,\sigma _2}-\delta }\), but \(\nabla u \notin L^{q_{\sigma _1,\sigma _2}}\). The existence of such optimal microgeometries is achieved by convex integration methods, adapting to the present setting the geometric constructions provided in Astala et al. (Ann Scuola Norm Sup Pisa Cl Sci 5(7):1–50, 2008) for the isotropic case.     

包含广义逆的算子乘积的谱

给定三个算子A,B,C∈ B(H),其中算子B的值域R(B)是闭的,利用算子矩阵分块技巧给出了∪σ(AB(1))C)=C的充分必要条件,其中σ(D)是算子D ∈B(H)的B(1) ∈B{1}谱,B{1}={X∈B(H):B×B=B}.     

The Generalized Weierstrass System for Nonconstant Mean Curvature Surfaces and the Nonlinear Sigma Model

A study of the generalized Weierstrass system which can be used to induce mean curvature surfaces in three-dimensional Euclidean space is presented. A specific transformation is obtained which reduces the initial system to a two-dimensional Euclidean nonlinear sigma model. Some aspects of integrability are discussed, in particular, a connection with a version of the sinh-Gordon equation is established. Finally, some specific solutions are given and a systematic way of calculating multisoliton solutions is presented.     

定向图的斜Randic能量

图G是一个简单无向图,G~σ是图G在定向σ下的定向图,G被称作G~σ的基础图.定向图G~σ的斜Randi6矩阵是实对称n×n矩阵R_s(G~σ)=[(r_s)_(ij)].如果(v_i,v_j)是G~σ的弧,那么(r_s)_(ij)=(d_id_j)~(-1/2)且(r_s)_(ji)=(d_id_j)~(-1/2),否则(r_s)_(ij)=(r_s)_(ji)=0.定向图G~σ的斜Randi能量RE_s(G~σ)是指R_s(G~σ)的所有特征值的绝对值的和.首先刻画了定向图G~σ的斜Randi矩阵R_s(G~σ)的特征多项式的系数.然后给出了定向图G~σ的斜Randi能量RE_s(G~σ)的积分表达式.之后给出了RE_s(G~σ)的上界.最后计算了定向圈的斜Randi能量RE_s(G~σ).     

POSITIVE MARTINGALES AND RANDOM MEASURES

Given Q_n(t) (n=0, 1,\cdots), a positive martingale indexed by t (t\in T, compact metric space) and a measure \sigma \in M^+(T), the random measure Q\sigma is defined as a limit of Q_n\sigma. In general EQ\sigma \leq \sigma. Conditions are given to insure either EQ\sigma=0 (degeneracy) or EQ\sigma=\sigma(full action). In the particular case when Q_n(t) a product of independent weight functions,\sigma is decomposed into a sum of two mutually singular measures,\sigma=\sigma''+\sigma'', such that Q acts fully on \sigma'' and is degeneoate on \sigma'', and the operator EQ is a projection. Examples and applications aoe given (random covecings, B. Mandelbrot''s martingales, multiplicative chaos).     

On the Flux-Across-Surfaces Theorem for Short-Range Potentials

The Flux-Across-Surfaces theorem is established for three-dimensional Schrödinger equation with short-range potentials V satisfying the decay condition for some . Exceptional cases are treated as well and the required decay index is . Explicit conditions for the initial states are found. A stationary representation for the integrated flux is obtained and exploited in the proof. Spatial asymptotic expansion of the resolvent is employed to calculate the limit of the integrated flux at spatial infinity. Communicated by Gian Michele Grafsubmitted 01/03/03, accepted 30/05/03