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991.
Peter Li Luen-fai Tam DaGang Yang 《Transactions of the American Mathematical Society》1998,350(3):1045-1078
We study the elliptic equation on complete noncompact Riemannian manifolds with nonnegative. Three fundamental theorems for this equation are proved in this paper. Complete analyses of this equation on the Euclidean space and the hyperbolic space are carried out when is a constant. Its application to the problem of conformal deformation of nonpositive scalar curvature will be done in the second part of this paper.
992.
993.
Let X be a strongly pseudoconvex compact 3-dimensional CR manifolds which bounds a complex variety with isolated singularities in some CN. The weighted dual graph of the exceptional set of the minimal good resolution of V is a CR invariant of X; in case X has a tranversal holomorphic S1 action, we show that it is a complete topological invariant of except for two special cases. When X is a rational CR manifolds, we give explicit algebraic algorithms to compute the graph invariant in terms of the ring structure of
k=0
mk/mk+1, where m is the maximal ideal of each singularity. An example is computed explicitly to demonstrate how the algorithms work. 相似文献
994.
Marco Romito 《Monatshefte für Mathematik》1998,126(4):329-352
Given an open bounded convex subset of
p
, a strictly elliptic differential operatorL and a continuous function
, and denoted withT
L the Dirichlet operator associated withL, the Lototsky-Schnabl operators associated withT
L and are investigated. In particular, conditions are established which ensure the existence of a Feller semigroup represented by limit of powers of these operators. Then the analytic expression of the infinitesimal generator is determined and some properties of the semigroup are deduced. Finally, the saturation class of Lototsky-Schnabl operators is determined.Work supported by a C.N.R. Research Grant (n. 201.19.1, November 30, 1994) 相似文献
995.
TAOYOUSHAN GAOGUOZHU 《高校应用数学学报(英文版)》1998,13(3):271-280
In this paper the forced neutral difterential equation with positive and negative coefficients d/dt [x(t)-R(t)x(t-r)] P(t)x(t-x)-Q(t)x(t-σ)=f(t),t≥t0,is considered,where f∈L^1(t0,∞)交集C([t0,∞],R^ )and r,x,σ∈(0,∞),The sufficient conditions to oscillate for all solutions of this equation are studied. 相似文献
996.
Zhu Ning 《高校应用数学学报(英文版)》1998,13(3):241-250
ANOTEONTHEBEHAVIOROFBLOW┐UPSOLUTIONSFORONE┐PHASESTEFANPROBLEMSZHUNINGAbstract.Inthispaper,thefolowingone-phaseStefanproblemis... 相似文献
997.
K. D. Kirchberg has given a minoration of the absolute value of the eigenvalues of the Dirac operator for a compact Kähler spin manifold (W,g) with positive scalar curvature and has introduced, in this context, the notion of Kähler twistor-spinor. We prove here that if dimC W = p 4 is even, in the limiting case, (W, g) is the Kähler product of an odd-dimensional limiting case compact Kähler spin manifold of complex dimension (p-1), by a flat Kähler manifold which is a compact quotient of C. 相似文献
998.
Glass formation and glass forming ability in the ternary Zr-Cu-Ni system were studied systematically. For Cu mold casting, the critical size for glass formation was found to be 1 mm in a relatively wide composition range of 56-64 at.% Zr, 16-26 at.% Cu and 16-24 at.% Ni. The phases competing with glass formation were found to be Zr, Zr2Cu and Zr2Ni. Despite the fact that Cu and Ni are completely miscible with each other, they cannot be regarded as simple substitution to each other in the case of glass formation in the Zr-Zr2Cu-Zr2Ni ternary eutectic system. 相似文献
999.
We consider the optimization problem of minimizing in the class of functions W1,G(Ω) with , for a given φ0?0 and bounded. W1,G(Ω) is the class of weakly differentiable functions with . The conditions on the function G allow for a different behavior at 0 and at ∞. We prove that every solution u is locally Lipschitz continuous, that it is a solution to a free boundary problem and that the free boundary, Ω∩∂{u>0}, is a regular surface. Also, we introduce the notion of weak solution to the free boundary problem solved by the minimizers and prove the Lipschitz regularity of the weak solutions and the C1,α regularity of their free boundaries near “flat” free boundary points. 相似文献
1000.
Ki-ahm Lee 《Advances in Mathematics》2008,219(6):2006-2028
We consider the asymptotic profiles of the nonlinear parabolic flows ut=Δum to show the geometric properties of the following elliptic nonlinear eigenvalue problems: