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991.
992.
Every group is the automorphism group of a rank-3 extension of a rank-3 Dowling geometry.Partially supported by The George Washington University UFF grant.Partially supported by the National Security Agency under grant MDA904-91-H-0030. 相似文献
993.
J.-P. Wintenberger 《Advances in Mathematics》2005,190(1):196-224
In this article, we prove, under some hypothesis of non ramification, a conjecture of Kottwitz and Rapoport giving the existence of crystals with additional structures. 相似文献
994.
4G手机无线接入系统设计及实现 总被引:1,自引:0,他引:1
用射频微波电路集成技术设计第4代(4G)手机无线接入系统.从分布参数概念出发,主要在smith圆图上进行电路设计.由微带线进行电路的实现,电路将各功能单元集成在微带基板上,具有体积小、重量轻、可靠性高、与手机其他电路易于共形等特点.运用网络转移参量矩阵理论进行了系统响应预估,结果表明所设计的无线接入系统满足4G移动终端的性能要求. 相似文献
995.
A.M. Cohen 《Numerische Mathematik》1994,68(2):225-238
Summary.
Wilkinson, in [1], has given a comprehensive account of the numerical
difficulties of working with polynomials on a floating point computer. The
object of this note is to attempt to rehabilitate the polynomial to a certain
extent. In particular it is shown here that polynomial deflation can be
performed satisfactorily by a method akin to `backward recursion'. Error
analyses and examples are given to illustrate the stability of the
process.
Received October 4, 1993 /
Revised version received July 14, 1993 相似文献
996.
J. Deák 《Periodica Mathematica Hungarica》1994,29(1):1-25
In Parts II to IV, we are going to investigate simultaneous extensions of various topological structures (i.e. traces on several subsets at the same time are prescribed), also with separation axioms T0, T1, symmetry (in the sense of Part I, § 3), Riesz property, Lodato property. The following questions will be considered: (i) Under what conditions is there an extension? (ii) How can the finest extension be described? (iii) Is there a coarsest extension? (iv) Can we say more about extensions of two structures than in the general case? (v) Assume that certain subfamilies (e.g. the finite ones) can be extended; does the whole family have an extension, too? The general categorial results from Part I will be applied whenever possible (even when they are not really needed). 相似文献
997.
Martin Lorenz 《Commentarii Mathematici Helvetici》1994,69(1):474-482
LetG be a finite group acting by automorphisms on an algebraS over some commutative ringk. We show that if the action ofG restricted to the center ofS is Galois in the sense of [C-H-R], thenHH
*(S
G)≊HH
*
(S)
G. An analogous result holds for cyclic homology, provided the order ofG is invertible ink.
The author was supported in part by a grant from the NSF. 相似文献
998.
A mode-coupling theory (MCT) is presented for the spin-boson model with a spectral density which accounts for a heat bath made up of lattice vibrations of a dielectric solid (superohmic dissipation). A usual decoupling approximation provides a set of non-linear integral equations which are solved both numerically by iteration on a computer and analytically by means of a frequency dependent ansatz for the memory functions. There is a transition to incoherent motion at a temperatureT
* where the bare two-level energy is equal to the damping rate, in contradiction to results obtained previously from a path integral formulation. The discrepancy arises since in the MCT the relevant self-energy function does not exhibit a 1/z-pole atz=0. For tunnelling systems in dielectrics this yields a new relaxation mechanism due to incoherent tunnelling: the present results might require to modify some of the basic assumptions of the standard tunnelling model for dielectric glasses. 相似文献
999.
Krantz Steven G. Li Song-Ying Rochberg Richard 《Integral Equations and Operator Theory》1997,28(2):196-213
The characterization of thosef for which the Hankel operatorsH
f belongs to various trace ideals over Bergman spaces on pseudoconvex domains of finite type in complex dimension two is given. In particular, we determine how the cutoff values are affected by the boundary geometry.All three authors supported by grants from the National Science Foundation 相似文献
1000.
Robert D. Skeel 《Numerische Mathematik》1986,48(1):1-20
Summary Various techniques that have been proposed for estimating the accumulated discretization error in the numerical solution of differential equations, particularly ordinary differential equations, are classified, described, and compared. For most of the schemes either an outline of an error analysis is given which explains why the scheme works or a weakness of the scheme is illustrated.This research is partially supported by NSF Grant No. MCS-8107046 相似文献