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991.
QIU Chunhui & ZHONG Tongde School of Mathematical Sciences Xiamen University Xiamen China Academy of Mathematics System Sciences Chinese Academy of Sciences Beijing China 《中国科学A辑(英文版)》2005,48(6):847-863
By means of the invariant integral kernel (the Berndtsson kernel), the complex Finsler metric and the non-linear connection associated with the Chern-Finsler connection to research into the integral representation theory on complex Finsler manifolds, the Koppelman and Koppelman-Leray formulas are obtained, and the (?)--equations are solved. 相似文献
992.
993.
C. Denson Hill Mauro Nacinovich 《Proceedings of the American Mathematical Society》2005,133(6):1843-1850
There is an intrinsic notion of what it means for a contact manifold to be the smooth boundary of a Stein manifold. The same concept has another more extrinsic formulation, which is often used as a convenient working hypothesis. We give a simple proof that the two are equivalent. Moreover it is shown that, even though a border always exists, its germ is not unique; nevertheless the germ of the Dolbeault cohomology of any border is unique. We also point out that any Stein fillable compact contact -manifold has a geometric realization in via an embedding, or in via an immersion.
994.
O.?P.?FerreiraEmail author L.?R.?Lucambio.?Pérez S.?Z.?Németh 《Journal of Global Optimization》2005,31(1):133-151
Bearing in mind the notion of monotone vector field on Riemannian manifolds, see [12--16], we study the set of their singularities and for a particularclass of manifolds develop an extragradient-type algorithm convergent to singularities of such vector fields. In particular, our method can be used forsolving nonlinear constrained optimization problems in Euclidean space, with a convex objective function and the constraint set a constant curvature Hadamard manifold. Our paper shows how tools of convex analysis on Riemannian manifolds can be used to solve some nonconvex constrained problem in a Euclidean space.O.P. Ferreira- was supported in part by CAPES, FUNAPE (UFG) and (CNPq).S.Z. Németh- was supported in part by grant No.T029572 of the National Research Foundation of Hungary. 相似文献
995.
Fumio Narita 《Geometriae Dedicata》1997,65(1):103-116
The main results of this paper are as follows. (a) Let : M N be a non-trivial Riemannian submersion with totally geodesic fibers of dimension 1 over an Einstein manifold N. If M is compact and admits a standard Einstein--Weyl structure with constant Einstein--Weyl function, then N admits a Kähler structure andM a Sasakian structure. (b) Let
be a Riemannian submersion with totally geodesic fibers and N an Einstein manifold of positive scalar curvature
. If M admits a standard Sasakian structure, then M admits an Einstein--Weyl structure with constant Einstein--Weyl function. 相似文献
996.
We consider compact locally conformal quaternion Kähler manifolds . This structure defines on a canonical foliation, which we assume to have compact leaves. We prove that the local quaternion Kähler metrics are Ricci-flat and allow us to project over a quaternion Kähler orbifold with fibers conformally flat 4-dimensional real Hopf manifolds. This fibration was known for the subclass of locally conformal hyperkähler manifolds; in this case we make some observations on the fibers' structure and obtain restrictions on the Betti numbers. In the homogeneous case is shown to be a manifold and this allows a classification. Examples of locally conformal quaternion Kähler manifolds (some with a global complex structure, some locally conformal hyperkähler) are the Hopf manifolds quotients of by the diagonal action of appropriately chosen discrete subgroups of .
997.
Hichem Sellami 《Mathematical Programming》1998,82(3):317-337
In this paper, we present a continuation method for solving normal equations generated byC
2
functions and polyhedral convex sets. We embed the normal map into a homotopyH, and study the existence and characteristics of curves inH
1(0) starting at a specificd point. We prove the convergence of such curves to a solution of the normal equation under some conditions on the polyhedral convex setC and the functionf. We prove that the curve will have finite are length if the normal map, associated with the derivative df(·) and the critical coneK, is coherently oriented at each zero of the normal mapf
c
inside a certain ball of
n
. © 1998 The Mathematical Programming Society, Inc. Published by Elsevier Science B.V.This research was performed at the Department of Industrial Engineering, University of Wisconsin-Madison, Madison, WI, USA. 相似文献
998.
Any transversally holomorphic foliated map
of Kählerianfoliations with
harmonic, is shown to be a transversallyharmonic map and an absolute minimum of the energy functional
inits foliated homotopy class. 相似文献
999.
A remarkable coincidence has led to the discovery of a family of packings of
-dimensional subspaces of m-dimensional space, whenever m is a power of 2. These packings meet the orthoplex bound and are therefore optimal. 相似文献
1000.
Qikeng Lu 《中国科学A辑(英文版)》1998,41(10):1061-1067
Let the coordinatex=(x
0,x
1,x
2,x
3) of the Minkowski spaceM
4 be arranged into a matrix
Then the Minkowski metric can be written as
. Imbed the space of 2 × 2 Hermitian matrices into the complex Grassmann manifoldF(2,2), the space of complex 4-planes passing through the origin ofC
2×4. The closure
ofM
4 inF(2,2) is the compactification ofM
4. It is known that the conformal group acts on
. It has already been proved that onF(2,2) there is anSu(2)-connection
whereZ is a 2 × 2 complex matrix andZ
†the complex conjugate and transposed matrix ofZ. Restrict this connection to
which is anSu(2)-connection on
. It is proved that its curvature form
satisfies the Yang-Mills equation
.
Project partially supported by the National Natural Science Foundation of China (Grant No. 19131010) and Fundamental Research
Bureau of CAS. 相似文献