A Comparison of Three-level Orthogonal Arrays in the Presence of a Possible Correlation in Observations

When we want to compare two designs we usually assume the standard linear model with uncorrelated observations. In this paper we use the comparison method proposed by Ghosh & Shen (2006) to compare three level orthogonal arrays with 18, 27 and 36 runs under a possible presence of correlation in observations.     

正交优化法的软件设计及其应用

本文用BASIC语言编制了正交优化法软件，并通过实例对其应用进行探讨，研究结果表明：用正交优化法处理化学、环保等方面的非线性模型的参数估值和非线性回归问题是非常有效的。     

A Construction of Lancaster Probabilities with Margins in the Multidimensional Meixner Class

The well-known Meixner class (Meixner, 1934) of probabilities on R has been extended recently to R ^d (Pommeret, 1996). This generalized Meixner class corresponds to the simple quadratic natural exponential families characterized by Casalis (1996). Following Lancaster (1975), the present paper offers a characterization of the joint probability of a randomvector ( X, Y ) such that the two variables X and Y on R ^d belong to the multidimensional Meixner class and fulfil a bi-orthogonality condition involving orthogonal polynomials. The joint probabilities, called Lancaster probabilities, are characterized by two sequences of orthogonal polynomials with respect to the margins and a sequence of expectations of products. Some multivariate probabilities are studied, namely the Poisson-Gaussian and the gamma-Gaussian.     

LDPC编码自适应加载MIMO-OFDM系统性能分析

介绍了LDPC校验阵的构造及编译码算法,采用了随机法构造LDPC校验阵,编码基于高斯消去直接进行译码采用无穷阶量化时的置信传播算法;讨论了OFDM自适应加载技术与多输入多输出技术,结合自适应比特功率分配算法与基于多载波调制的比特分配方案实现了该加载分配技术;给出了LDPC编码的自适应加载MIMO-OFDM系统的模型。经仿真分析得出,二元域上非规则LDPC编码的系统性能优于多元域上的,自适应加载MIMO-OFDM技术大大提高了系统传输速率,有效增强了系统抗衰落性。     

基于波导模式正交的新吸收边界条件

提出了一种可同时吸收波导内行波和雕落波型的新型吸收边界条件。与常规的吸收边界条件相结合，在这种新的吸收边界条件下，可将边界紧置于不连续区附近而保持计算精度，使计算时间和对计算机内存的要求都大大下降。数值计算的例子表明用新的边界条件计算出的结果与用常用吸收边界条件计算出的结果吻合得很好     

Construction of orthogonal factorial designs controlling interaction efficiencies

This paper employs some variants of the usual Kronecker product to construct orthogonal factorial designs controlling the interaction efficiencies. The methods suggested have a fairly wide coverage and the resulting designs involve a small number of replicates.     

Some resolvable orthogonal arrays with two symbols

A method of constructing a resolvable orthogonal array (4λk2,2) which can be partitioned into λ orthogonal arrays (4,k 2,1) is proposed. The number of constraints kfor this type of orthogonal array is at most 3λ. When λ=2 or a multiple of 4, an orthogonal array with the maximum number of constraints of 3λ can be constructed. When λ=4n+2(n≧1) an orthogonal array with 2λ+2 constraints can be constructed. When λ is an odd number, orthogonal arrays can be constructed for λ=3,5,7, and 9 with k=4,8,12, and 13 respectively.     

Cutting Experimental Designs into Blocks

Most experimental material in agriculture and industry is heterogeneous in nature and therefore its statistical analysis benefits from blocking. Many experiments are restricted in time or space, and again blocking is useful. This paper adopts the idea of orthogonal blocking of Box & Hunter (1957) and applies it to optimal blocking designs. This approach is then compared with the determinant-based approach described in the literature for constructing block designs.     

关于二维小波函数的进一步探讨

对二维小被函数作了进一步分析，讨论了二维频率响应的计算，将二维尺度函数用乘积空间中勒让德正交多项式展开，得到了一些可喜结果。     

基于灰色关联分析的注塑成型工艺参数优化设计

本工作研究了灰色关联分析法在注塑成型工艺参数优化中的应用，通过专家评估和实践经验确立工艺参数评价指标的理论期望值，采用正交法设计试验方案，基于灰色关联分析计算其关联度．以寻求最接近理论期望值的注塑工艺方案，为实现注塑工艺参数的优化提供了一种有效的手段。