EXISTENCE OF AREA MINIMIZING TANGENT CONES OF INTEGRAL CURRENTS WITH PRESCRIBED MEAN CURVATURE

ＥＸＩＳＴＥＮＣＥＯＦＡＲＥＡＭＩＮＩＭＩＺＩＮＧＴＡＮＧＥＮＴＣＯＮＥＳＯＦＩＮＴＥＧＲＡＬＣＵＲＲＥＮＴＳＷＩＴＨＰＲＥＳＣＲＩＢＥＤＭＥＡＮＣＵＲＶＡＴＵＲＥ￥ＦｒａｎｋＤｕｚａａｒ（ＩｎｓｔｉｔｕｔｆｕｒＡｕｇｅｗａｎｄｔｅＭａｔｈｅｍａｔｉ...     

ON THE EXISTENCE THEOREMS OF NONTRIVIAL PERIODIC SOLUTIONS TOA CLASS OF NONLINEAR NON－AUTONOMOUS SYS

ＯＮＴＨＥＥＸＩＳＴＥＮＣＥＴＨＥＯＲＥＭＳＯＦＮＯＮＴＲＩＶＩＡＬＰＥＲＩＯＤＩＣＳＯＬＵＴＩＯＮＳＴＯＡＣＬＡＳＳＯＦＮＯＮＬＩＮＥＡＲＮＯＮ－ＡＵＴＯＮＯＭＯＵＳＳＹＳＴＥＭＳ￥ＧａｏＺｈａｎｈａｉ（高占海）；ＺｈａｎｇＤｉ（张棣）（Ｎｏｒｔｈ...     

ADMISSIBILITY FOR LINEAR ESTIMATES ON REGRESSION COEFFICIENTS IN A GENERAL MULTIVARIATE LINEAR MODEL

ＡＤＭＩＳＳＩＢＩＬＩＴＹＦＯＲＬＩＮＥＡＲＥＳＴＩＭＡＴＥＳＯＮＲＥＧＲＥＳＳＩＯＮＣＯＥＦＦＩＣＩＥＮＴＳＩＮＡＧＥＮＥＲＡＬＭＵＬＴＩＶＡＲＩＡＴＥＬＩＮＥＡＲＭＯＤＥＬＸｉｅＭｉｎｙｕ（谢民育）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ...     

EXISTENCE AND ESTIMATION OF SOLUTIONS FOR SINGULARLY PERTURBED VECTOR IMPULSIVE PROBLEMS

ＥＸＩＳＴＥＮＣＥＡＮＤＥＳＴＩＭＡＴＩＯＮＯＦＳＯＬＵＴＩＯＮＳＦＯＲＳＩＮＧＵＬＡＲＬＹＰＥＲＴＵＲＢＥＤＶＥＣＴＯＲＩＭＰＵＬＳＩＶＥＰＲＯＢＬＥＭＳＸｕＹｕｘｉｎｇ（许玉兴）＆ＺｈａｎｇＸｉａｎｇ（张祥）（ＡｎｈｕｉＮｏｒｍａｌＵｎｉｖｅｒｓ...     

A COMPLETE METRIC OF POSITIVE CURVATURE ON R~n AND EXISTENCE OF CLOSED GEODESICS

ＡＣＯＭＰＬＥＴＥＭＥＴＲＩＣＯＦＰＯＳＩＴＩＶＥＣＵＲＶＡＴＵＲＥＯＮＲ~ｎＡＮＤＥＸＩＳＴＥＮＣＥＯＦＣＬＯＳＥＤＧＥＯＤＥＳＩＣＳ￥ＺＨＵＤＡＸＩＮ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙｌＴｉａｎｊ?..     

ON BAHADUR－TYPE ASYMPTOTIC EFFICIENCY OF POINT ESTIMATORS UNDER IRREGULAR TRUNCATED DISTRIBUTION FAM

ＯＮＢＡＨＡＤＵＲ－ＴＹＰＥＡＳＹＭＰＴＯＴＩＣＥＦＦＩＣＩＥＮＣＹＯＦＰＯＩＮＴＥＳＴＩＭＡＴＯＲＳＵＮＤＥＲＩＲＲＥＧＵＬＡＲＴＲＵＮＣＡＴＥＤＤＩＳＴＲＩＢＵＴＩＯＮＦＡＭＩＬＹ￥ＣｈｅｎＧｕｉｊｉｎｇ（陈桂景）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔ...     

K－网格上有限元的超收敛性及渐近准确的后验误差估计

Ｋ－网格上有限元的超收敛性及渐近准确的后验误差估计黄云清，陈艳萍（湘潭大学数学系）ＴＨＥＳＵＰＥＲＣＯＮＶＥＲＧＥＮＣＥＡＮＤＡＳＹＭＰＴＯＴＩＣＡＬＬＹＥＸＡＣＴＡＰＯＳＴＥＲＩＯＲＩＥＲＲＯＲＥＳＴＩＭＡＴＥＯＦＴＨＥＦＩＮＩＴＥＥＬＥＭＥＮＴＯ...     

ADMISSIBILITY OF LINEAR ESTIMATE OF REGRESSION COEFFICIENTS IN GROWTH CURVE MODEL UNDER MATRIX LOSS

ＡＤＭＩＳＳＩＢＩＬＩＴＹＯＦＬＩＮＥＡＲＥＳＴＩＭＡＴＥＯＦＲＥＧＲＥＳＳＩＯＮＣＯＥＦＦＩＣＩＥＮＴＳＩＮＧＲＯＷＴＨＣＵＲＶＥＭＯＤＥＬＵＮＤＥＲＭＡＴＲＩＸＬＯＳＳＷＡＮＧＸＵＥＲＥＮ（王学仁）（ＤｅｐａｒｔｍｅｎｔｏｆＳｔａｔｉｓｔｉｃｓ，...     

A CLASS OF SECOND ORDER NEUTRAL DIFFERENTIAL INEQUALITIES WITH DISTRIBUTED TYPE DEVIATING ARGUMENTS

ＡＣＬＡＳＳＯＦＳＥＣＯＮＤＯＲＤＥＲＮＥＵＴＲＡＬＤＩＦＦＥＲＥＮＴＩＡＬＩＮＥＱＵＡＬＩＴＩＥＳＷＩＴＨＤＩＳＴＲＩＢＵＴＥＤＴＹＰＥＤＥＶＩＡＴＩＮＧＡＲＧＵＭＥＮＴＳ（傅希林）￥ＦｕＸｉｌｉｎ（Ｄｅｐｔ．ｏｆＭａｔｈ．，ＳｈａｎｄｏｎｇＮｏｒ...     

K－网格上有限元的超收敛性及渐近准确的后验误差估计

Ｋ－网格上有限元的超收敛性及渐近准确的后验误差估计黄云清，陈艳萍（湘潭大学数学系）ＴＨＥＳＵＰＥＲＣＯＮＶＥＲＧＥＮＣＥＡＮＤＡＳＹＭＰＴＯＴＩＣＡＬＬＹＥＸＡＣＴＡＰＯＳＴＥＲＩＯＲＩＥＲＲＯＲＥＳＴＩＭＡＴＥＯＦＴＨＥＦＩＮＩＴＥＥＬＥＭＥＮＴＯ...     

Linear Versus Nonlinear Rules for Mixture Normal Priors

The problem under consideration is the -minimax estimation, under L₂loss, of a multivariate normal mean when the covariance matrix is known. The family of priors is induced by mixing zero mean multivariate normals with covariance matrix I by nonnegative random variables , whose distributions belong to a suitable family G. For a fixed family G, the linear (affine) -minimax rule is compared with the usual -minimax rule in terms of corresponding -minimax risks. It is shown that the linear rule is "good", i.e., the ratio of the risks is close to 1, irrespective of the dimension of the model. We also generalize the above model to the case of nonidentity covariance matrices and show that independence of the dimensionality is lost in this case. Several examples illustrate the behavior of the linear -minimax rule.     

Stability results for an inverse problem in potential theory

Sunto Nel presente lavoro consideriamo un problema inverso, connesso a questioni di elettrocardiologia, relativo a un potenziale di doppio strato obliquo logaritmico, u, portato da una curva piana . Il problema consiste nel determinare conoscendo u sulla frontiera di un dominio T contenente . Il problema non è ben posto secondo Hadamard. Introduciamo delle limitazioni a priori su e dimostriamo alcuni risultati di stabilità.     

On groups of polynomial subgroup growth

Summary Let be a finitely generated group anda _n ()=the number of its subgroups of indexn. We prove that, assuming is residually nilpotent (e.g., linear), thena _n () grows polynomially if and only if is solvable of finite rank. This answers a question of Segal. The proof uses a new characterization ofp-adic analytic groups, the theory of algebraic groups and the Prime Number Theorem. The method can be applied also to groups of polynomial word growth.Oblatum 1-VII-1989 & 7-VI-1990     

Die Automorphismengruppen hyperelliptischer Kurven

Let be a hyperelliptic curve over an algebraically closed field of characteristic O and G a group of automorphisms of that contains the canonical involution of . We describe the group-theoretical structure of G by means of the arithmetical structure of the morphism ^G.     

Critical points of essential norms of singular integral operators in weighted spaces

We show that for any simple piecewise Ljapunov contour there exists a power weight such that the essential norm |S | in the spaceL ₂(, ) does not depend on the angles of the contour and it is given by formula (2). All such weights are described. For the union =₁₂ of two simple piecewise Lyapunov curves we prove that the essential norm |S | inL ₂() is minimal if both ₁ and ₂ are smooth in some neighborhoods of the common points. It is the case when the norm |S | in the spaceL ₂() as well as inL ₂(, ) does not depend on the values of the angles and it can be calculated by formula (5).     

On the removable singularities of CR functions given on a generic manifold

Summary In this paper we consider the problem of holomorphic continuation and removal of singularities of the CR functions given on K, where is a generic manifold with nondegenerate Levi form and K is a meromorphically p-convex compactum. We get some conditions on , relative to p-convexity and q-concavity, under which every integrable CR function given on K extends holomorphically in some domain \K, where is a wedge domain with edge . Our Results are local.Authors had a support of Russian Fund of Fundamental Investigations (grant 93-011-258).     

Free Algebras of Automorphic Forms on the Upper Half-Plane

We find all pairs (,a) consisting of a cocompact Fuchsian group of genus zero and an automorphy factor a of for which the graded algebra of a--automorphic forms is free.     

Solution of Dirichlet's problem for the equation Δu =−1 in a convex region

Let u be a solution of the following boundary-value problem: u¦ = 0, where is a closed convex curve and u = –1 in the region D bounded by . Then u has only one local maximum, and all its level curves are convex.Translated from Matematicheskie Zametki, Vol. 9, No. 1, pp. 89–92, January, 1971.     

On Locally Projective Graphs of Girth 5

Let be a graph and G be a 2-arc transitive automorphism group of . For a vertex x let G(x)^(x) denote the permutation group induced by the stabilizer G(x) of x in G on the set (x) of vertices adjacent to x in . Then is said to be a locally projective graph of type (n,q) if G(x)^(x) contains PSL_n(q) as a normal subgroup in its natural doubly transitive action. Suppose that is a locally projective graph of type (n,q), for some n 3, whose girth (that is, the length of a shortest cycle) is 5 and suppose that G(x) acts faithfully on (x). (The case of unfaithful action was completely settled earlier.) We show that under these conditions either n=4, q=2, has 506 vertices and , and contains the Wells graph on 32 vertices as a subgraph. In the latter case if, for a given n, at least one graph satisfying the conditions exists then there is a universal graph W(n) of which all other graphs for this n are quotients. The graph W(3) satisfies the conditions and has 2²⁰ vertices.     

Extended generalized octagons and the groupHe

Let be an extended generalized octagon such that the points of a triple {u, v, w} not on a block are pairwise adjacent if and only if the distance betweenv andw in the local generalized octagon _u equals 3 and there is a thick line through any point of _u . Then is one of the two examples related to the groups 2·L ₃(4).2² andHe. It is also shown that does not admit further extensions.