RELATIONSHIPS AMONG CLASSES OF SPHERICAL MATRIX DISTRIBUTIONS

Several classes of spherical matrix distributions have been studied by many authors.In thispaper the relationships among the classes are discussed in the following aspects:the characteristicfunctions in these classes,coordinate transformations,marginal distributions,marginal densities,and sphericity.Some statistics that are invariant in these classes are listed for applications.     

The Convergence of (r|~)_s(b_0h_n-h_1b_(n-1))

This paper computes the Thorn map onγ2 and proves that it is represented by 2b2,0h1,2 in the ASS. The authors also compute the higher May differential of 62,0, from which it is proved thatγs(b0hn-h1bn-1) for 2≤s < p - 1 are permanent cycles in the ASS.     

亚纯函数的n阶导数分享1值点的唯一性的一些结果

In this paper, we consider the problem of the uniqueness for meromorphic functions whose n-th derivatives share the same 1-points. The results in this paper are different from all of theorems given by H X Yi and C C Yang and other authors.     

Maximal Operators of Multilinear Singular Integrals on Weighted Hardy Type Spaces*

In this paper, the authors show that the maximal operators of the multilinear Calderón-Zygmund singular integrals are bounded from a product of weighted Hardy spaces into a weighted Lebesgue spaces, which essentially extend and improve the previous known results obtained by Grafakos and Kalton(2001) and Li, Xue and Yabuta(2011). The corresponding estimates on variable Hardy spaces are also established.     

《数学年刊》第35卷B辑第6期(2014)目次和提要(英文)

<正>Nonlocal Symmetries and Explicit Solutions of the Boussinesq Equation Xiangpeng XIN Junchao CHEN Yong CHEN The nonlocal symmetry of the Boussinesq equation is obtained from the known Lax pair.The explicit analytic interaction solutions between solitary waves and cnoidal waves are obtained through the localization procedure of nonlocal symmetry.Some other types of solutions,such as rational solutions and error function solutions,are given by using the fourth Painleve equation with special     

Finite Atomic Decomposition Characterization of Variable Anisotropic Hardy Spaces

In 2011, Dekel et al. developed highly geometric Hardy spaces H^p(Θ), for the full range 0n with high anisotropy in the sense that the ellipsoids can change shape rapidly from point to point and from level to level.The authors obtain the finite atomic decomposition characterization of Hardy spaces H^p(Θ) and as an application, the authors prove that given an admissible triplet(p, q, l) w...     

由复映射z←zα+c(α<0)所构造的广义M-集的研究

This paper expounds the escape time algorithm of constructing general Mandelbrot sets from the complex mapping z←z^α+c(α<0). A series of interesting and rich families of fractal images are generated by changing a single parameter α. The fractal images consist of planetary structures with a central planet surrounded by satellite structures. The positions and sizes of the planet and satellite structures are analytically estimated. The embryonic satellite structure arising for non-integer values of α are also analysed. In the end, a few conclusions are reached.     

Quasi-convex Functions in Carnot Groups

In this paper, the authors introduce the concept of h-quasiconvex functions on Carnot groups G. It is shown that the notions of h-quasiconvex functions and h-convex sets are equivalent and the L∞estimates of first derivatives of h-quasiconvex functions are given. For a Carnot group G of step two, it is proved that h-quasiconvex functions are locally bounded from above. Furthermore, the authors obtain that h-convex functions are locally Lipschitz continuous and that an h-convex function is twice differentiable almost everywhere.     

Recognizing Finite Groups Through Order and Degree Patterns

The degree pattern of a finite group G associated with its prime graph has been introduced by Moghaddamfar in 2005 and it is proved that the following simple groups are uniquely determined by their order and degree patterns:All sporadic simple groups,the alternating groups Ap(p≥5 is a twin prime)and some simple groups of the Lie type.In this paper,the authors continue this investigation.In particular,the authors show that the symmetric groups Sp+3,where p+2 is a composite number and p+4 is a prime and 97相似文献   

Deleting Vertices and Interlacing Laplacian Eigenvalues

The authors obtain an interlacing relation between the Laplacian spectra of a graph G and its subgraph G - U, which is obtained from G by deleting all the vertices in the vertex subset U together with their incident edges. Also, some applications of this interlacing property are explored and this interlacing property is extended to the edge weighted graphs.     

Bicompleting weightable quasi-metric spaces and partial metric spaces

We show that the bicompletion of a weightable quasi-metric space is a weightable quasi-metric space. From this result we deduce that any partial metric space has an (up to isometry) unique partial metric bicompletion. Some other consequences are derived. In particular, applications to two interesting examples of partial metric spaces which appear in Computer Science, as the domain of words and the complexity space, are given. The second and third listed authors are partially supported by grants from Spanish Ministry of Science and Technology, BFM 2000-III, and Polytechnical University of Valencia.     

Optimal control systems with state variable jump discontinuities

Consideration is given to continuous-time, parameter-dependent optimal control problems with state-variable jump discontinuities atN variable interior times. A maximum principle involving known costate jump conditions is stated and is proved by transforming the problem into a standard Mayer control problem. An illustrative example for fisheries management is included.This work was partially supported by a grant from Control Data. The authors are grateful to Professor T. L. Vincent for drawing their attention to Refs. 4–6 listed below.     

关于两个n维单形的棱长与体积的两类不等式

给出了联系两个n维单形的棱长与体积的两类不等式,从而推广和改进了相关文献的结果.     

Relationships among classes of spherical matrix distributions

Several classes of spherical matrix distributions have been studied by many authors. In this paper the relationships among the classes are discussed in the following aspects: the characteristic functions in these classes, coordinate transformations, marginal distributions, marginal densities, and sphericity. Some statistics that are invariant in these classes are listed for applications.This paper was printed as Technical Report No. 10, ARO Contract DAAG 29-82-K-0156, Department of Statistics, Stanford University, Stanford, California, April 1984.     

Bifurcations of travelling wave solutions for a two-component camassa-holm equation

By using the method of dynamical systems to the two-component generalization of the Camassa-Holm equation, the existence of solitary wave solutions, kink and anti-kink wave solutions, and uncountably infinite many breaking wave solutions, smooth and non-smooth periodic wave solutions is obtained. Under different parametric conditions, various sufficient conditions to guarantee the existence of the above solutions are given. Some exact explicit parametric representations of travelling wave solutions are listed.     

ZI数据的统计分析综述

ZI (zero-inflated)数据就是含零过多的数据.从上世纪90年代以来, ZI数据在各个研究领域受到越来越广泛的重视,现在仍然是数据分析的热点问题之一.本文首先通过2个实例说明ZI数据的实际意义,然后介绍ZI数据分析的研究概况和最新进展.另外文章还系统介绍了各种ZI数据模型、ZI纵向数据模型及其参数估计方法,同时也介绍了ZI数据的统计诊断等问题, 其中包括作者近年来的一些工作.最后, 本文列出了若干有待进一步研究的问题.     

基于财务状况多分类的上市公司财务危机预警

目前的财务危机预警模型大多局限于二分类研究,而公司陷入财务危机往往会经历一个逐步衰败的过程,简单的二分类有时会掩盖某些上市公司财务状况逐渐变差的事实.为了更准确地判断公司的财务状况,将公司分为财务稳定公司、潜在危机公司、财务危机公司和破产公司四类,运用t-2年的财务数据构建了有序多分类logistic回归模型.实证结果表明,模型的预测能力较好,误判成本较低,能提供更加准确的信息.     

Interactive video: A bridge between motion and math

This paper examines the characteristics of interactive digitized video as a medium in which motion is presented to students learning graphical representations. We situate graphs of motion as early topics in learning calculus, the bugaboo of many math students. In comparing video to both everyday perceptions and mathematical representations, we construct a conceptual framework that compares these three contexts along several dimensions: object extent, scale, time, and space. We then examine one student's experience constructing graphs of her own design from a video image and describe her work in the context of the our conceptual framework. To further specify the unique characteristics of video, we compare it as a medium with that of computer simulations of motion, in particular as studied by diSessa et al. (1991).The authors are listed in alphabetical order.     

管理者过度自信对高技术企业技术外部获取方式选择的影响研究

企业管理者的业绩预测偏差是衡量管理者是否过度自信的一个重要体现,值得关注和研究。本研究采用我国2004~2013年高技术上市公司的相关数据,应用Ordered-probit模型实证分析了管理者过度自信对高技术上市公司技术外部获取方式选择的影响。研究结果表明:我国高技术上市公司以非股权技术联盟作为首要的技术外部获取方式,公司风险投资是最后的选择;同时,研究发现:在对技术外部获取方式进行选择时,管理者过度自信的高技术上市公司选择并购优先于合资和少数持股联盟,而管理者非过度自信的高技术上市公司选择少数持股联盟优先于并购和合资。该研究方法简单、高效、合理,是企业高管提升公司管理水平和科学获取技术外部的一种新的方法选择。     

基于最优负债系数的上市银行违约概率测算模型与实证

当上市银行的长期负债系数γ的取值不同时,应用KMV模型测算出的银行违约概率大相径庭。根据债券的实际信用利差可以推算出上市银行的违约概率PDi,CS,根据长期负债系数γ可以运用KMV模型确定上市银行的理论违约概率PDi,KMV。本文通过理论违约率与实际违约率的总体差异∑ni=1|PDi,KMV-PDi,cs|最小的思路建立规划模型,确定了KMV模型的最优长期负债γ系数;通过最优长期负债系数γ建立了未发债上市银行的违约率测算模型、并实证测算了我国14家全部上市银行的违约概率。本文的创新与特色一是采用KMV模型计算的银行违约概率PDi,KMV与实际信用利差确定的银行违约概率PDi,CS总体差异∑ni=1|PDi,KMV-PDi,cs|最小的思路建立规划模型,确定了KMV模型中的最优长期负债γ系数;使γ系数的确定符合资本市场利差的实际状况,解决了现有研究中在0和1之间当采用不同的长期负债系数γ、其违约概率的计算结果截然不同的问题。二是实证研究表明,当长期负债系数γ=0.7654时,应用KMV模型测算出的我国上市银行违约概率与我国债券市场所接受的上市银行违约概率最为接近。三是实证研究表明国有上市银行违约概率最低,区域性的上市银行违约概率较高,其他上市银行的违约概率居中。