On the tangent space to the BMO-Teichmüller space

In a previous paper [31] we established the complex analytic manifold theory of the BMO-Teichmüller space. In this paper we identify the function space which is the tangent space to the BMO-Teichmüller space.     

Once more about the state-minimization of the nondeterministic finite automata

In this paper we consider the corrected version of the algorithm of the state-minimization for the nondeterministic finite automata: we correct here a mistake of the previous paper, where the same problem was considered.     

Connections in fiberings associated with the Grassman manifold and the space of centered planes

In the present paper we study connections in the fiberings associated with the Grassmann manifold and the space of the centered planes. The work is related to the studies in differential geometry. In the paper, we use the method of continuations and scopes of G. F. Laptev which generalizes the moving frame method and the exterior forms method of Cartan; the method depends on calculation of exterior differential forms. In the paper, we develop a new method of research in Grassman manifolds and some generalization of the method which includes the theory of the induced connections of the spaces of planes and centered planes in the n-dimensional projective space.     

极值分布的一个注记

本文对PH极值分布进行了推广,应用构造相关联的Markov过程的方法,证明了n个相互独立的PH随机变量构成的次序随机变量的分布仍是PH分布。并给出了次序PH随机变量分布表达式的表示方法,本文同时也给出了次序PH随机变量的联合生存分布,本文最后给出了次序PH随机变量在可靠性理论与更新理论中的应用。     

影子价格与企业管理决策

本文利用线性规划与非线性规划模型，讨论了目标函数增量，影子价格及相应的常数项增量的特征区间之间的关系，从理论上对文[1]、[2]、[3]中的问题作出了解释。我们还给出了线性规划与非线性规划发生悖论的充要条件，对文[5]、[7]中的结果进行了推广。     

On the four current source of the electromagnetic fields

Summary In this paper, we consider the field equations of Einstein-Maxwell theory in the presence of a four-current source J with vanishing Lorentz force. By relating J with one of the eigenvalues of the contracted curvature tensor, we discuss some of its properties. In particular, we find certain geometric conditions governing the direction of J. Physically, the results of this paper may be applicable in the study of the history traced by J and in the theory of geometrodynamics. Entrata in Redazione il 26 agosto 1978. This research was supported by the National Research Council of Canada.     

On the image of the Burau representation of the IA-automorphism group of a free group

In this paper we study the graded quotients of the lower central series of the image of the IA-automorphism group of a free group by the Burau representation. In particular, we determine their structures for degrees 1 and 2.     

关于二元四次型正定问题的若干注记

§ 1 .　IntroductionInthestudyofdifferentialequationsandothermathematicalandphysicalfields,weoftenneedtodealwiththerootdistributionofanequationandthepositivedefinite,negativedefiniteproblemsofabinaryquarticformsee [2 ,3,4].Itiswellknownthatinthecaseofaquadraticform ,therearemanycriterionsforthepositivedefiniteandnegativeproblems.Forthecaseofabinaryquarticformthestudyonthepositivedefiniteproblemsisfarfromcompletelyunder standing .Thepaper[1]hasdonesomeworksonthisfield.Butitisapitythatthereares…     

A Note on the Finite Variance of the Averaging Function for Polynomial System Solving

In the forthcoming paper of Beltrán and Pardo, the average complexity of linear homotopy methods to solve polynomial equations with random initial input (in a sense to be described below) was proven to be finite, and even polynomial in the size of the input. In this paper, we prove that some other higher moments are also finite. In particular, we show that the variance is polynomial in the size of the input.     

非齐次Rosenau-Burgers方程的三种数值方法比较

提出了求解非齐次Rosenau-Burgers方程的三种有限差分的数值方法,经分析得到了第三种格式的唯一可解性及稳定性和误差估计.最后,通过具有精确解的数值算例验证了三种方法的可靠性和精确性.     

不可约圈与路之并补图的色唯一性

讨论了形如ｋＣＲＵｒＰＲ的一类图的补图的色性．在一定的条件下证明了这类图是色唯一的．本文推广了文［１］的结果．     

On the Stability of the Directional Regularity

In this paper we select two tools of investigation of the classical metric regularity of set-valued mappings, namely the Ioffe criterion and the Ekeland Variational Principle, which we adapt to the study of the directional setting. In this way, we obtain in a unitary manner new necessary and/or sufficient conditions for directional metric regularity. As an application, we establish stability of this property at composition and sum of set-valued mappings. In this process, we introduce directional tangent cones and the associated generalized primal differentiation objects and concepts. Moreover, we underline several links between our main assertions by providing alternative proofs for several results.

     

Constant angle surfaces in the Lorentzian Heisenberg group

In this paper, we define and, then, we characterize constant angle spacelike and timelike surfaces in the three-dimensional Heisenberg group, equipped with a 1-parameter family of Lorentzian metrics. In particular, we give an explicit local parametrization of these surfaces and we produce some examples.     

Critical points of the integral map of the charged three-body problem

This is the first in a series of three papers where we study the integral manifolds of the charged three-body problem. The integral manifolds are the fibers of the map of integrals. Their topological type may change at critical values of the map of integrals. Due to the non-compactness of the integral manifolds one has to take into account besides ‘ordinary’ critical points also critical points at infinity. In the present paper we concentrate on ‘ordinary’ critical points and in particular elucidate their connection to central configurations. In a second paper we will study critical points at infinity. The implications for the Hill regions, i.e. the projections of the integral manifolds to configuration space, are the subject of a third paper.     

On the optimality of the greedy solutions of the general knapsack problems

Summary: In this paper we submit a unified discussion of some closely related results which were achieved independently in number theory and integer programming, and we partially generalize them. In the unified discussion we treat together two problems where the greedy method has different characters, in the first one it is an internal-point algorithm, in the second one it is an outer-point method. We call a knapsack problem "pleasant" if the greedy solution is optimal for every right-hand side. A sufficient and two finite necessary and sufficient conditions for the pleasantness of a problem are discussed. The sufficient condition can be checked very easily. The paper is finished with an error analysis of some nonpleasant problems     

Laws of the single logarithm for delayed sums of random fields II

In an earlier paper we extended Lai's (1974) law of the single logarithm for delayed sums to a class of delayed sums of random fields. In this paper we allow for more general windows.     

Parabolic Second-Order Directional Differentiability in the Hadamard Sense of the Vector-Valued Functions Associated with Circular Cones

In this paper, we study the parabolic second-order directional derivative in the Hadamard sense of a vector-valued function associated with circular cone. The vector-valued function comes from applying a given real-valued function to the spectral decomposition associated with circular cone. In particular, we present the exact formula of second-order tangent set of circular cone by using the parabolic second-order directional derivative of projection operator. In addition, we also deal with the relationship of second-order differentiability between the vector-valued function and the given real-valued function. The results in this paper build fundamental bricks to the characterizations of second-order necessary and sufficient conditions for circular cone optimization problems.     

Lower Bounds for the Eigenvalues of the Dirac Operator: Part II. The Submanifold Dirac Operator

In this paper we generalize the results of Part I to the submanifoldDirac operator. In particular, we give optimal lower bounds for thesubmanifold Dirac operator in terms of the mean curvature and othergeometric invariants as the Yamabe number or the energy-momentum tensor.In the limiting case, we prove that the submanifold is Einstein if thenormal bundle is flat.     

On the total coloring of certain graphs

In this paper we investigate the total chromatic number of certain graphs. In particular, we show that every cubic graph is totally colorable in five colors.     

Symmetry analysis of the two-dimensional diffusion equation with a source term

A symmetry analysis is performed on a (2+1)-dimensional linear diffusion equation with a nonlinear source term involving the dependent variable and its spatial derivatives. In the first part of the paper, we use the classical method to classify source terms where the original equation admits a nontrivial symmetry. In the second part of the paper, we use the nonclassical method and show that we simply recover the classical symmetries.