Analysis of Polychlorinated Biphenyl Mixtures and Establishment of a Parameter Useful for PCB‐Degradation Studies

Abstract

A prerequisite for the study of polychlorinated biphenyls (PCBs) is a reliable analytical determination of the substances involved. For this purpose a gas chromatographic (GC) separation method with detection by mass spectrometry (MS) was optimized. In addition, a new parameter—the “weighted average chlorination level”—was established. This forms the basis for a systematic investigation of the reductive dechlorination of PCBs by metals.     

加权正则函数的一些性质

正则函数是Clifford分析中的一类重要函数,加权正则函数是正则函数的进一步发展,也是一类重要的函数,因此具有一定的研究意义.在正则函数的研究基础上,并利用加权正则函数自身的性质,讨论了加权正则函数的平均值定理,最大模原理,Weierstrass定理以及一些其它推论.     

An improved method on group decision making based on interval-valued intuitionistic fuzzy prioritized operators

Interval-valued intuitionistic fuzzy prioritized operators are widely used in group decision making under uncertain environment due to its flexibility to model uncertain information. However, there is a shortcoming in the existing aggregation operators (interval-valued intuitionistic fuzzy prioritized weighted average (IVIFPWA)) to deal with group decision making in some extreme situations. For example, when an expert gives an absolute negative evaluation, the operators could lead to irrational results, so that they are not effectively enough to handle group decision making. In this paper, several examples are illustrated to show the unreasonable results in some of these situations. Actually, these unreasonable cases are common for operators in dealing with product averaging, not only emerging in IVIFPWA operators. To overcome the shortcoming of these kinds of operators, an improvement of making slight adjustment on initial evaluations is provided. Numerical examples are used to show the efficiency of the improvement.     

Analysis of plate rolling by MY criterion and global weighted velocity field

A three-dimensional velocity field for plate rolling is proposed by global weighted method. Then, using the field and linear MY (mean yield) criterion, the power functional of internal deformation for plate rolling is analyzed. The collinear vector inner product is used in the friction power functional. Ultimately, analytical solution of total power functional is obtained. By minimizing the power functional, the rolling force and torque, as well as the stress effective factor are obtained. The calculated results by the solutions of rolling torque and force are compared with those of experimental ones. Good agreement is found and the maximum error percentage between them is less than 15.5%.     

鞅差序列加权和的几乎处处收敛(英文)

本文研究了一类鞅差序列加权和的收敛性的问题.利用一些基本不等式和截尾技术,获得了加权和的几乎处处收敛性,推广了关于独立同分布的随机变量序列的相关结果.     

带振荡核奇异积分算子交换子在加权Morrey空间中的有界性质

本文研究Morrey空间中的交换子有界性的问题.利用John-Nirenberg不等式等工具建立带振荡核的奇异积分算子与BMO函数生成交换子在加权Morrey空间中的加权估计.     

局部平稳扩散模型中时变参数的加权最小二乘估计

基于离散观测样本,利用局部线性拟合,得到了局部平稳扩散模型中时变漂移参数的加权最小二乘估计,并讨论了估计量的相合性,渐近正态性和一致收敛速度.同时,通过模拟研究说明了估计量的有效性.     

Lagrange插值在—重积分Wiener空间下的同时逼近平均误差

在加权L_p范数逼近意义下,确定了基于扩充的第二类Chebyshev结点组的Lagrange插值多项式列,在一重积分Wiener空间下同时逼近平均误差的渐近阶.结果显示,在L_p范数逼近意义下,Lagrange插值多项式列逼近函数及其导数的平均误差都弱等价于相应的最佳逼近多项式列的平均误差.同时,在信息基复杂性的意义下,若可允许信息泛函为标准信息,则上述插值算子列逼近函数及其导数的平均误差均弱等价于相应的最小非自适应信息半径.     

Graded mesh refinement and error estimates of higher order for DGFE solutions of elliptic boundary value problems in polygons

Error estimates for DGFE solutions are well investigated if one assumes that the exact solution is sufficiently regular. In this article, we consider a Dirichlet and a mixed boundary value problem for a linear elliptic equation in a polygon. It is well known that the first derivatives of the solutions develop singularities near reentrant corner points or points where the boundary conditions change. On the basis of the regularity results formulated in Sobolev–Slobodetskii spaces and weighted spaces of Kondratiev type, we prove error estimates of higher order for DGFE solutions using a suitable graded mesh refinement near boundary singular points. The main tools are as follows: regularity investigation for the exact solution relying on general results for elliptic boundary value problems, error analysis for the interpolation in Sobolev–Slobodetskii spaces, and error estimates for DGFE solutions on special graded refined meshes combined with estimates in weighted Sobolev spaces. Our main result is that there exist a local grading of the mesh and a piecewise interpolation by polynoms of higher degree such that we will get the same order O (h^α) of approximation as in the smooth case. © 2011 Wiley Periodicals, Inc. Numer Mehods Partial Differential Eq, 2012     

加权平方损失下伽玛分布族Γ(θ,1/2)参数θ的EB估计

在加权平方损失函数下讨论了伽玛分布族T(θ,1/2)参数θ的经验Bayes(EB)估计,并讨论了EB估计的收敛速度问题,在一定条件下,收敛速度可充分接近于1.