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91.
We call a one-way infinite word w over a finite alphabet (ρ,l)-repetitive if all long enough prefixes of w contain as a suffix a ρth power (or more generally a repetition of order ρ) of a word of length at most l. We show that each (2,4)-repetitive word is ultimately periodic, as well as that there exist continuum many, and hence also nonultimately periodic, (2,5)-repetitive words. Further, we characterize nonultimately periodic (2,5)-repetitive words both structurally and algebraically. 相似文献
92.
设f是非常数亚纯函数,g是f的线性微分多项式.a和b是f的两个不同的小函数.本文证明如果f和g几乎CM分担a和b,则f≡g;此外,若f是非常数整函数,且f和f(k)(k≥1)IM分担a和b,b-a≠Peλz,测f≡g. 相似文献
93.
设珮犠(狋):犚犖+ →犚犱是犖指标犱维广义Wiener过程,对任意紧集犈1,…,犈犿犚犖> ,该文研究了犿项代数和珮犠(犈1)…珮犠(犈犿)的Hausdorff维数,Packing维数和正的Lebesgue测度及内点的存在性. 其结果包含并推广了布朗单的结果. 相似文献
94.
Alexander Krasnosel'skii Dmitrii Rachinskii 《NoDEA : Nonlinear Differential Equations and Applications》2002,9(1):93-115
We consider autonomous systems with a nonlinear part depending on a parameter and study Hopf bifurcations at infinity. The
nonlinear part consists of the nonlinear functional term and the Prandtl--Ishlinskii hysteresis term. The linear part of the
system has a special form such that the close-loop system can be considered as a hysteresis perturbation of a quasilinear
Hamiltonian system. The Hamiltonian system has a continuum of arbitrarily large cycles for each value of the parameter. We
present sufficient conditions for the existence of bifurcation points for the non-Hamiltonian system with hysteresis. These
bifurcation points are determined by simple characteristics of the hysteresis nonlinearity. 相似文献
95.
F.E. SalmanN. Shash H. Abou El-HadedM.K. El-Mansy 《Journal of Physics and Chemistry of Solids》2002,63(11):1957-1966
AC conductivity and dielectric studies on vanadium phosphate glasses doped with lithium have been carried out in the frequency range 0.2-100 kHz and temperature range 290-493 K. The frequency dependence of the conductivity at higher frequencies in glasses obeys a power relationship, σac=Aωs. The obtained values of the power s lie in the range 0.5≤s≤1 for both undoped and doped with low lithium content which confirms the electron hopping between V4+ and V5+ ions. For doped glasses with high lithium content, the values of s≤0.5 which confirm the domination of ionic conductivity. The study of frequency dependence of both dielectric constant and dielectric loss showed a decrease with increasing frequency while they increase with increasing temperature. The results have been explained on the basis of frequency assistance of electron hopping besides the ionic polarization of the glasses. The bulk conductivity increases with increasing temperature whereas decreases with increasing lithium content which means a reduction of the V5+. 相似文献
96.
K. Yatsu T. Cho H. Higaki M. Ichimura K. Ishii Y. Ishimoto M. K. Islam A. Itakura I. Katanuma J. Kohagura Y. Nakashima T. Saito Y. Takemura Y. Tatematsu M. Yoshida M. Yoshikawa 《Czechoslovak Journal of Physics》2002,52(10):1143-1148
GAMMA 10 experiments have advanced in high density experiments after the last EPS Workshop where we reported high density
plasma production by using an ion cyclotron range of frequency heating at a high harmonic frequency and neutral beam injection
in the central cell. Recently a high density plasma was obtained with much improved reproducibility than before and without
degradation of diamagnetic signal. The high density plasma was attained by adjusting the spacing of the conducting plates
installed in the anchor transition regions. Dependencies of particle confinement time, ion energy confinement time and plasma
confining potential on plasma density were obtained for the first time in the high density region.
Presented at 5th Workshop “Role of Electric Fields in Plasma Confinement and Exhaust”, Montreus, Switzerland, June 23–24,
2002. 相似文献
97.
Matroid bundles, introduced by MacPherson, are combinatorial analogues of real vector bundles. This paper sets up the foundations
of matroid bundles. It defines a natural transformation from isomorphism classes of real vector bundles to isomorphism classes
of matroid bundles. It then gives a transformation from matroid bundles to spherical quasifibrations, by showing that the
geometric realization of a matroid bundle is a spherical quasifibration. The poset of oriented matroids of a fixed rank classifies
matroid bundles, and the above transformations give a splitting from topology to combinatorics back to topology. A consequence
is that the mod 2 cohomology of the poset of rank k oriented matroids (this poset classifies matroid bundles) contains the free polynomial ring on the first k Stiefel-Whitney classes. 相似文献
98.
关于AOR迭代法的研究 总被引:5,自引:0,他引:5
陈恒新 《应用数学与计算数学学报》2002,16(1):40-46
本文论证了严格对角占优矩阵之AOR法的误差估计式中的误差估计常数hγ,ω(0≤γ≤ω0)的最小值是h1,1. 相似文献
99.
线性分式规划最优解集的求法 总被引:5,自引:0,他引:5
薛声家 《应用数学与计算数学学报》2002,16(1):90-96
本文使用多面集的表示定理,导出了线性分式规划最优解集的结构,并给出确定全部最优解的计算步骤。 相似文献
100.
曾六川 《数学物理学报(A辑)》2002,22(1):99-106
该文研究Banach空间中一类强增生型变分包含解的存在性及其具误差的Ishikawa迭代程序的收敛性问题.该文结果是几位作者早期与最近的相应结果的改进和推广. 相似文献