任意凸多面体上布点均匀性的度量

均匀性度量是构作均匀设计的基础,本文从距离概念出发,通过对称的方法,得到一种新的距离函数-势函数,并将势函数作为衡量任意凸多面体上布点均匀性好坏的准则.数值例子和多变量Kendall 协和系数检验表明,当试验区域限制在单位立方体上时,势函数与目前常用的两种偏差-中心化L_2-偏差和可卷L_2.偏差在度量布点均匀性方面结论一致.     

带有定性因素均匀设计的均匀性度量准则

我们在文〔3〕中曾讨论了如何用均匀设计来安排含有定性因素的试验。在文〔1〕中所使用的均匀设计表是针对试验中全为连续因素设计的。显然 ,当试验中含有定性因素时 ,均匀性的度量和相应均匀设计表的设计都会有所不同。这是一个值得研究的课题。本文主要探讨均匀性的度量 ,并用文中提出的准则 ,对文〔1〕中一些均匀设计表的均匀性给出了数值性结果     

均匀性度量中的密集性偏差与稀疏性偏差

该文根据王元，方开泰［２］的近似偏差（discrepancy）的均匀性准则，定义了理想布点情况下的标准半径，定义了ｍ 维单位子空间Ｃｍ＝［０，１］中两点间的ｆ距离和ｇ距离，由此定义了最大空穴半径和最小空穴半径，提出了均匀性度量的密集性偏差与稀疏性偏差．给出了二维情况 下的计算结果．我们的方法计算量不大，不仅能较好地度量布点的均匀性以及布点在低维投影的均匀性，而且能指导如何调整布点使之尽可能与理想布点接近．     

均匀设计及其应用（Ⅲ）

均匀设计及其应用（Ⅲ）方开泰第三章均匀设计表的构造本章介绍均匀设计表的构造和使用表的来源，其中涉及到均匀度的度量。在理解了表的构造原理冬我们就能比较灵活地运用均匀设计，故本章也介绍均匀设计这方面的知识。§１均匀设计表的构造定义１：每一个均匀设计表是一...     

三角型模糊数空间的均匀性

用（Ｔ，ｄ）表示全体三角型模糊数构成的度量空间，本文证明了（Ｔ，ｄ）具有某种度量均匀性，并证明了（Ｔ，ｄ）是连通与局部连通的空间。     

低偏差OALHD的构造

本文给出了利用均匀设计和正交表构造低偏差OALH设计的方法，该方法构造的设计既有优良的均匀性具有正交设计的均衡性，一个更重要的优点是可以构造较大样本容量的设计点集，本文同时给出了某些参数的均匀设计表，这些设计优于现有的均匀设计，具有实用价值。     

混水平均匀设计的构造

我们用离散偏差来度量部分因子设计的均匀性,本文的目的在于寻找一些构造混水平均匀设计的方法,这些方法比文献中已有的方法更简单且计算成本更低.我们得到了离散偏差的一个下界,如果一个U 型设计的离散偏差值达到这个下界,那么该设计是—个均匀设计.我们建立了均匀设计与组合设计理论中一致可分解设计之间的联系.通过一致可分解设计,我们提出了一些构造均匀设计的新方法,同时也给出了许多均匀设计存在的无穷类.     

抽样设计偏差的大样本性质

偏差（Ｄｉｓｃｒｅｐａｎｃｙ）作为布点设计均匀性的一个重要度量准则,已被使用很长时间,但对它的性质还研究得很不够．该文从模平移的方面系统地研究了偏差的性质,给出了在超立方体中一个布点设计按整体、大格子、小格子各种模平移的偏差大样本性质,这些性质对于计算机试验引进有关的设计和抽样方法起着重要的作用．     

正交设计的最新发展和应用(Ⅱ)-均匀正交设计

方开泰等．正交设计的最新发展和应用（Ⅱ）—均匀正交设计．令Ｌ（ｎ;ｑｓ）为一切正交表Ｌｎ（ｑｓ）之集合,Ｍ为试验点分布于试验区域的均匀性测度。给定（ｎ,ｑ,ｓ）,在Ｌ（ｎ;ｑｓ）上具有最好均匀性（在测度ＭＦ）的设计称为无匀正交设计,并表为ＵＬｎ（ｑｓ）。本讲座以ＵＬ９（３４）为例说明均匀正交设计在估计和混杂方面的优良性质。在附录中列出了七个均匀正交表,它们都是最近获得的     

正交设计的最新发展和应用(Ⅱ)—均匀正交设计

方开泰等．正交设计的最新发展和应用（Ⅱ）—均匀正交设计．令Ｌ（ｎ;ｑｓ）为一切正交表Ｌｎ（ｑｓ）之集合,Ｍ为试验点分布于试验区域的均匀性测度。给定（ｎ,ｑ,ｓ）,在Ｌ（ｎ;ｑｓ）上具有最好均匀性（在测度ＭＦ）的设计称为无匀正交设计,并表为ＵＬｎ（ｑｓ）。本讲座以ＵＬ９（３４）为例说明均匀正交设计在估计和混杂方面的优良性质。在附录中列出了七个均匀正交表,它们都是最近获得的     

投影均匀分片拉丁超立方体设计

空间填充设计是有效的计算机试验设计,比如均匀设计、最大最小距离拉丁超立方体设计等.虽然这些设计在整个试验空间中有较好的均匀性,但其低维投影均匀性可能并不理想.对于因子是定量的计算机试验,已有文献构造了诸如最大投影设计、均匀投影设计等相适应的设计;而对于同时含有定性因子和定量因子的计算机试验,尚未有投影均匀设计的相关文献.文章提出了综合投影均匀准则,利用门限接受算法构造了投影均匀的分片拉丁超立方体设计.在新构造设计中,整体设计与每一片设计均具有良好的投影均匀性.模拟结果显示,与随机分片拉丁超立方体设计相比,利用新构造设计进行试验而拟合的高斯过程模型具有更小的均方根预测误差.     

Distributing points uniformly on the unit sphere under a mirror reflection symmetry constraint

Uniformly distributed point sets on the unit sphere with and without symmetry constraints have been found useful in many scientific and engineering applications. Here, a novel variant of the Thomson problem is proposed and formulated as an unconstrained optimization problem. While the goal of the Thomson problem is to find the minimum energy configuration of N electrons constrained on the surface of the unit sphere, this novel variant imposes a new symmetry constraint – mirror reflection symmetry with the x–y plane as the plane of symmetry. Qualitative features of the two-dimensional projection of the optimal configurations are briefly mentioned and compared to the ground-state configurations of the two dimensional system of charged particles laterally confined by a parabolic potential well.     

均匀设计在研究C/Cu复合材料耐磨损设计准则中的应用

本文用均匀设计安排 Ｃ／ Ｃｕ 复合材料的磨损试验，用逐步回归方法建立了可靠度与载荷ｐ、速度ｖ 的回归方程，它有助于对 Ｃ／ Ｃｕ 复合材料磨损性能设计准则进行研究     

An algorithmic approach to finding factorial designs with generalized minimum aberration

Factorial designs are arguably the most widely used designs in scientific investigations. Generalized minimum aberration (GMA) and uniformity are two important criteria for evaluating both regular and non-regular designs. The generation of GMA designs is a non-trivial problem due to the sequential optimization nature of the criterion. Based on an analytical expression between the generalized wordlength pattern and a uniformity measure, this paper converts the generation of GMA designs to a constrained optimization problem, and provides effective algorithms for solving this particular problem. Moreover, many new designs with GMA or near-GMA are reported, which are also (nearly) optimal under the uniformity measure.     

A simple scheme for generating nearly uniform distribution of antipodally symmetric points on the unit sphere

A variant of the Thomson problem, which is about placing a set of points uniformly on the surface of a sphere, is that of generating uniformly distributed points on the sphere that are endowed with antipodal symmetry, i.e., if x is an element of the point set then -x is also an element of that point set. Point sets with antipodal symmetry are of special importance to many scientific and engineering applications. Although this type of point sets may be generated through the minimization of a slightly modified electrostatic potential, the optimization procedure becomes unwieldy when the size of the point set increases beyond a few thousands. Therefore, it is desirable to have a deterministic scheme capable of generating this type of point set with near uniformity. In this work, we will present a simple deterministic scheme to generate nearly uniform point sets with antipodal symmetry.     

Symmetry classes of tensors and semi-direct product of finite abelian groups

In the study of symmetry classes of tensors, finding examples of symmetry classes of tensors that possess an o*-basis is of considerable interest. There are only few classes of groups that have been provided a necessary and sufficient condition for having such a basis. There is no general criterion for any finite group yet. In this note, we provide a necessary and sufficient condition for the existence of o*-basis of symmetry classes of tensors associated with semi-direct product of some finite abelian groups and, consequently, their wreath product.