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111.
A logarithmic Gauss curvature flow and the Minkowski problem 总被引:1,自引:0,他引:1
Kai-Seng Chou Xu-Jia Wang 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2000,17(6):733
Let X0 be a smooth uniformly convex hypersurface and f a postive smooth function in Sn. We study the motion of convex hypersurfaces X(·,t) with initial X(·,0)=θX0 along its inner normal at a rate equal to log(K/f) where K is the Gauss curvature of X(·,t). We show that the hypersurfaces remain smooth and uniformly convex, and there exists θ*>0 such that if θ<θ*, they shrink to a point in finite time and, if θ>θ*, they expand to an asymptotic sphere. Finally, when θ=θ*, they converge to a convex hypersurface of which Gauss curvature is given explicitly by a function depending on f(x). 相似文献
112.
113.
Professor C.J. Scriba 《Historia Mathematica》1984,11(2):222-225
114.
We transform the problem of determining isometric immersions from H
2(-1) into H
3(c) (c of solving an elliptic Monge--Ampère equation on the unit disc. Then we classify isometric immersions which possess bounded principal curvatures. 相似文献
115.
116.
Fernando Pablos Romo 《Proceedings of the American Mathematical Society》2007,135(7):1977-1985
The aim of this note is to offer a new explicit expression of the Contou-Carrère symbol that depends only on a product of a finite number of terms. As an application, we obtain an explicit formula for a Witt Residue.
117.
A. Taskaraev 《Mathematical Notes》1998,64(5):658-662
The existence and uniqueness of a surface with given geometric characteristics is one of the important topical problems of
global differential geometry. By stating this problem in terms of analysis, we arrive at second-order elliptic and parabolic
partial differential equations. In the present paper we consider generalized solutions of the Monge-Ampère equation ||z
ij
|| = ϕ(x, z, p) in Λ
n
, wherez = z(x
1,...,z
n
) is a convex function,p = (p
1,...,P
n) = (∂z/∂x
1,...,ϖz/ϖx
n), andz
ij =ϖ
2
z/ϖx
i
ϖx
j. We consider the Cayley-Klein model of the space Λ
n
and use a method based on fixed point principle for Banach spaces.
Translated fromMatematicheskie Zametki, Vol. 64, No. 5, pp. 763–768, November, 1998. 相似文献
118.
119.
J. Spiliotis 《Applied Mathematics and Optimization》1997,35(3):265-282
The complex parabolic type Monge-Ampère equation we are dealing with is of the form
inB × (0,T),u=ϕ on Γ, whereB is the unit ball in ℂ
d
,d>1, and Γ is the parabolic boundary ofB × (0,T). Solutionu is proved unique in the class
. 相似文献
120.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(9):2430-2434
Recent reports demonstrate that a two‐dimensional (2D) structural characteristic can endow perovskites with both remarkable photoelectric conversion efficiency and high stability, but the synthesis of ultrathin 2D perovskites with large sizes by facile solution methods is still a challenge. Reported herein is the controlled growth of 2D (C4H9NH3)2PbBr4 perovskites by a chlorobenzene‐dimethylformide‐acetonitrile ternary solvent method. The critical factors, including solvent volume ratio, crystallization temperature, and solvent polarity on the growth dynamics were systematically studied. Under optimum reaction condition, 2D (C4H9NH3)2PbBr4 perovskites, with the largest lateral dimension of up to 40 μm and smallest thickness down to a few nanometers, were fabricated. Furthermore, various iodine doped 2D (C4H9NH3)2PbBrx I4−x perovskites were accessed to tune the optical properties rationally. 相似文献