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151.
Sylvain Maillot 《Geometric And Functional Analysis》2007,17(3):839-851
We show that open 3-manifolds that have a locally finite decomposition along 2-spheres are characterized by the existence
of a Riemannian metric with respect to which the second homotopy group of the manifold is generated by small elements.
Received: November 2005 Revision: February 2006 Accepted: May 2006 相似文献
152.
Michèle Audin 《manuscripta mathematica》2007,124(4):533-550
In this paper, we investigate symplectic manifolds endowed with a Morse–Bott function with only two critical submanifolds,
one of which is Lagrangian while the other one is symplectic. 相似文献
153.
For a general K3 surface S of genus g, with 2 ≤ g ≤ 10, we prove that the intermediate Jacobians of the family of prime Fano threefolds of genus g containing S as a hyperplane section, form generically an algebraic completely integrable Hamiltonian system.
The first author is partially supported by grant MI1503/2005 of the Bulgarian Foundation for Scientific Research. 相似文献
154.
In this paper, we establish a theorem on the distribution of primes in quadratic progressions on average. 相似文献
155.
We prove that three automorphisms of the rooted binary tree defined by a certain 3-state automaton generate a free non-Abelian
group of rank 3.
Both authors are supported by the NSF grants DMS-0308985 and DMS-0456185. Yaroslav Vorobets is supported by a Clay Research
Scholarship. 相似文献
156.
K A Dowsland M Gilbert G Kendall 《The Journal of the Operational Research Society》2007,58(4):429-438
This paper is concerned with the development of a customized circle packing algorithm for a manufacturer of sprockets for the motor cycle industry. Practical constraints mean that the problem differs somewhat from those tackled elsewhere in the literature. In particular, the layouts need to conform to a given structure. This is achieved by using a local search algorithm with an appropriate starting solution and a series of neighbourhoods designed to preserve the layout structure. Empirical evidence based on real data shows that the quality of the resulting solutions closely matches that of cutting patterns currently produced by human experts. Computation times average around 20–30?s per order as compared to several hours for an equivalent manual solution. 相似文献
157.
Gu-Qiang Li 《Theoretical and Mathematical Physics》2007,151(1):586-589
We use the Parikh-Wilczek method to treat Hawking radiation as a tunneling process across the event horizon and calculate
the emission rate of a Gibbons-Maeda dilaton black hole. We show that if self-gravitation is taken into account, then the
radiation deviates from the purely thermal spectrum, and the corrected spectrum is consistent with an underlying unitary theory.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 151, No. 1, pp. 172–175, April, 2007. 相似文献
158.
In this paper we investigate the electrostatic problem of determining conductivity profiles from the knowledge of boundary
currents and voltages. We obtain an improved estimate for the voltage potential of a two-dimensional conductor having finitely
many circular inclusions and piecewise constant conductivity profile. We derive an asymptotic expansion for the voltage potential
in terms of the reference voltage potential and the location, size, and conductivity of the inhomogeneities. This representation
is used to formulate the nonlinear least squares problem for estimating the location and size of the inhomogeneities. Required
boundary data for the voltage potential are generated numerically by solving a system of integral equations. Computational
experiments are presented to demonstrate the effectiveness of our identification procedure. 相似文献
159.
Semyon Alesker 《Geometric And Functional Analysis》2007,17(4):1321-1341
This is a non-technical survey of a recent theory of valuations on manifolds constructed in [A10], [A11], [AF] and [A12],
and actually a guide to this series of articles. We also review some recent related results obtained by a number of people.
Received: February 2006, Revision: June 2006, Accepted: June 2006 相似文献
160.