可能性与必要性测度性质及可能多目标线性规划的模糊有效解关系定理

在文 [1 ]基础上 ,深入研究了可能性与必要性测度的重要性质 ;通过反例指出在一般情形下 ( A,B至少有一个为严格模糊集合 )由“NA( B) >0”出发 ,得不出“πA( B) =1”的结论 ;同时 ,论证了上述结论成立的条件 ,以此为基础 ,得到两种测度的相关定理。这样 ,便纠正了文[1 ]中的错误。接下来研究了可能多目标规划问题中的两种解——必要有效解与可能有效解之间的关系 ,得到相应的关系定理。作为它的应用 ,我们给出三个实例     

Banach空间中二阶非线性脉冲微分-积分方程的初值问题

通过引进等价的范数,应用Ｂａｎａｃｈ不动点定理,在较宽松的条件下,获得了Ｂａｎａｃｈ空间中二阶非线性脉冲微分－积分方程初值问题解的存在与唯一性及解的迭代逼近。对文「５」（Ｊ．Ｍａｔｈ．Ａｎａｌ．Ａｐｐｌ．２０００（１９９６）,１－１３）相应于ｄ０＝０的结果作了重要改进和推广。该文条件易于判断,方法也本质地不同于文「５」。     

一类中立型泛函微分方程的周期解

本文考虑一类中立型微分差分方程ｘ′（ｔ）＋Ｃｘ′（ｔ－ｒ）＝Ａ（ｔ,ｘ）ｘ（ｔ）＋ｆ（ｔ,ｘ（ｔ－ｒ））,利用矩阵测度结合不动点定理的方法,得到其周期解存在的充分条件,所得定理改进或推广了「１－３」中的有关结果。     

希尔伯特空间中半线性随机发展方程适度解的存在性

本文讨论如下形式的希尔伯特空间中半线性随机发展方程Ｃａｕｃｈｙ问题｛ｄｙ（ｔ）「Ａｙ（ｔ）＝ｆ（ｔ，ｙ（ｔ））」ｄｔ＋Ｇ（ｔ，ｙ（ｔ））ｄｗ（ｔ）ｙ（０）＝ｙ０适度解的存在性。在一组条件下得到了解的整体存在性，推广了文「１」的存在性定理。     

GAOR迭代法收敛判别准则

本文将文「１」中给出的判别超松驰（即ＳＯＲ）迭代法的一个收敛性准则推广到ＧＡＯＲ迭代法，并且去掉了Ａ为不可约矩阵或／ａｉｉ／＋ｕｉ〉０（ｉ＝１，２，…，ｎ）这一条件，本文的结果所涉及的和收敛范围，均扩广交包含了文「１」中的定理。     

广义Lienard方程非平凡周期解的存在性

本文给出了广义Ｌｉｅｎａｒｄ方程ｘ＋ｆ（ｘ）（ｘ）ｘ＋ｇ（ｘ）＝０存在非平凡周期解的两个充分条件,推广了文「４,５」中的结果,并且指出文「１」中的一个疏漏。     

Banach空间中—u‘’∈F（t,u（t）,u（t））的解

本文给出了弱序列完备Ｂａｎａｃｈ空间中二阶微分包含的解的存在性定理，推广了「１」中的结果到集值情形，同时由于利用已有的定理「２」，简化了类似「１」宫的证明。     

模糊值函数与模糊数积分区间[A,B]上的N—L公式

文「１」给出模糊值函数在普通区间「ａ,ｂ」上的Ｎ－Ｌ公式。本文在文「１」的基础上进一步给出模糊值函数区间「Ａ,Ｂ」上的积分。这个积分是Ⅱ型糊集。文「３」已经指出（Ｆ２「１,１」,∪,∩,ｃ）不是软代数,但这个积分是一个特殊Ⅱ型模糊集具有许多良好的代数性质,并存在着Ｎ－Ｌ公式。     

包含度空间中的收敛性

本文引入包含度空间中的Ｄ－收敛和滤子收敛,并证明二者等价;然后给出Ｌ＾ｐ「ａ,ｂ」（１≤ｐ〈∞）空间中的又一种包含度收敛,证明其与测度收敛等价。     

Banach空间中复合增算子的不动点定理

本文给出Ｂａｎａｃｈ空间中集值与单位的增逄子的不动点定理，它推广了文「１」－「４」中相应的结果。     

Linear birth and death models and associated Laguerre and Meixner polynomials

We study birth and death processes with linear rates λ_n = n + α + c + 1, μ_{n + 1} = n + c, n 0 and μ₀ is either zero or c. The spectral measures of both processes are found using generating functions and the integral transforms of Laplace and Stieltjes. The corresponding orthogonal polynomials generalize Laguerre polynomials and the choice μ₀ = c generates the associated Laguerre polynomials of Askey and Wimp. We investigate the orthogonal polynomials in both cases and give alternate proofs of some of the results of Askey and Wimp on the associated Laguerre polynomials. We also identify the spectra of the associated Charlier and Meixner polynomials as zeros of certain transcendental equations.     

Distributive and Multiplication Modules and Rings

We study rings in which every ideal is a finitely generated multiplication right ideal.     

Affine-inscribed and affine-circumscribed polygons and polytopes

Five theorems on polygons and polytopes inscribed in (or circumscribed about) a convex compact set in the plane or space are proved by topological methods. In particular, it is proved that for every interior point O of a convex compact set in ℝ³, there exists a two-dimensional section through O circumscribed about an affine image of a regular octagon. It is also proved that every compact convex set in ℝ³ (except the cases listed below) is circumscribed about an affine image of a cube-octahedron (the convex hull of the midpoints of the edges of a cube). Possible exceptions are provided by the bodies containing a parallelogram P and contained in a cylinder with directrix P. Bibliography: 29 titles. Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 231, 1995, pp. 286–298. Translated by B. M. Bekker.     

Partitions and pairwise sums and products

A seven cell partition of N is constructed with the property that no infinite set has all of its pairwise sums and products in any one cell. A related Ramsey Theory question is shown to have different answers for two and three cell partitions.     

Ritz and harmonic Ritz values and the convergence of FOM and GMRES

The Ritz and harmonic Ritz values are approximate eigenvalues, which can be computed cheaply within the FOM and GMRES Krylov subspace iterative methods for solving non‐symmetric linear systems. They are also the zeros of the residual polynomials of FOM and GMRES, respectively. In this paper we show that the Walker–Zhou interpretation of GMRES enables us to formulate the relation between the harmonic Ritz values and GMRES in the same way as the relation between the Ritz values and FOM. We present an upper bound for the norm of the difference between the matrices from which the Ritz and harmonic Ritz values are computed. The differences between the Ritz and harmonic Ritz values enable us to describe the breakdown of FOM and stagnation of GMRES. Copyright © 1999 John Wiley & Sons, Ltd.     

Beliefs and beyond: affect and the teaching and learning of mathematics

The importance of beliefs for the teaching and learning of mathematics is widely recognized among mathematics educators. In this special issue, we explicitly address what we call “beliefs and beyond” to indicate the larger field surrounding beliefs in mathematics education. This is done to broaden the discussion to related concepts (which may not originate in mathematics education) and to consider the interconnectedness of concepts. In particular, we present some new developments at the conceptual level, address different approaches to investigate beliefs, highlight the role of student beliefs in problem-solving activities, and discuss teacher beliefs and their significance for professional development. One specific intention is to consider expertise from colleagues in the fields of educational research and psychology, side by side with perspectives provided by researchers from mathematics education.