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991.
Geometric aspects of the moduli space of Riemann surfaces 总被引:10,自引:0,他引:10
Shing-Tung Yau 《中国科学A辑(英文版)》2005,48(Z1)
We describe some recent progress in the study of moduli space of Riemann surfaces in this survey paper. New complete Kahler metrics were introduced on the moduli space and Teichmuller space. Their curvature properties and asymptotic behavior were studied in details. These natural metrics served as bridges to connect all the known canonical metrics, especially the Kahler-Einstein metric. We showed that all the known complete metrics on the moduli space are equivalent and have Poincare type growth. Furthermore, the Kahler-Einstein metric has strongly bounded geometry. This also implied that the logarithm cotangent bundle of the moduli space is stable in the sense of Mumford. 相似文献
992.
Common fixed point results for noncommuting mappings without continuity in cone metric spaces 总被引:1,自引:0,他引:1
The existence of coincidence points and common fixed points for mappings satisfying certain contractive conditions, without appealing to continuity, in a cone metric space is established. These results generalize several well-known comparable results in the literature. 相似文献
993.
In this paper, we investigate the long-range dependence of fractional Lévy processes on Gel’fand triple and construct stochastic
integral with respect to fractional Lévy processes for a class of deterministic integrands.
相似文献
994.
基于K型区间删失数据,利用样本空间排序法给出参数优良的置信下限和计算置信下限的递推公式. 相似文献
995.
本文给出四阶整数辛群中扭元的全部共轭等价类.总共有55个不同的扭元等价类,它们的阶数分别是2, 3, 4, 5, 6, 8, 10, 12.没有其它阶的扭元. 相似文献
996.
我们研制了CEBQ程序和ENVLOP程序,模拟稳态相对论电子束在二极管区的产生和加速,以及电子束在阳极通道内的传输过程。CEBQ程序模拟二极管区电子轨道,当阳极电压为1.5MV时,阴极总发射电流为17.9kA,进入阳极通道内的传输电流为4.3kA,阳极入口处D=4cm的束发射度为24.9cm.mrad。ENVLOP程序使用线性近似下的包络方程,描述电子束包络在螺旋管引导磁场作用下的变化,讨论了外加引导磁场对包络的影响。计算结果表明,在合适引导磁场作用下,束包络起伏较小,进入阳极通道的束流(4.3kA)能全部通过。 相似文献
997.
John D. Ramshaw 《Journal of statistical physics》1989,56(1-2):149-158
Phase space density representations of inviscid fluid dynamics were recently discussed by Abarbanel and Rouhi. Here it is shown that such representations may be simply derived and interpreted by means of the Liouville equation corresponding to the dynamical system of ordinary differential equations that describes fluid particle trajectories. The Hamiltonian and Poisson bracket for the phase space density then emerge as immediate consequences of the corresponding structure of the dynamics. For barotropic fluids, this approach leads by direct construction to the formulation presented by Abarbanel and Rouhi. Extensions of this formulation to inhomogeneous incompressible fluids and to fluids in which the state equation involves an additional transported scalar variable are constructed by augmenting the single-particle dynamics and phase space to include the relevant additional variable. 相似文献
998.
M. Pappalardo 《Journal of Optimization Theory and Applications》1990,64(1):141-152
In this paper, we introduce a unified framework for the study of penalty concepts by means of the separation functions in the image space (see Ref. 1). Moreover, we establish new results concerning a correspondence between the solutions of the constrained problem and the limit points of the unconstrained minima. Finally, we analyze some known classes of penalty functions and some known classical results about penalization, and we show that they can be derived from our results directly. 相似文献
999.
Anna Ja?kiewicz Andrzej S. Nowak 《Journal of Mathematical Analysis and Applications》2006,316(2):495-509
We consider Markov control processes with Borel state space and Feller transition probabilities, satisfying some generalized geometric ergodicity conditions. We provide a new theorem on the existence of a solution to the average cost optimality equation. 相似文献
1000.
I numerically simulate and compare the entanglement of two quanta using the conventional formulation of quantum mechanics and a time-symmetric formulation that has no collapse postulate. The experimental predictions of the two formulations are identical, but the entanglement predictions are significantly different. The time-symmetric formulation reveals an experimentally testable discrepancy in the original quantum analysis of the Hanbury Brown–Twiss experiment, suggests solutions to some parts of the nonlocality and measurement problems, fixes known time asymmetries in the conventional formulation, and answers Bell’s question “How do you convert an ’and’ into an ’or’?” 相似文献