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941.
Wen heng Wang 《数学学报(英文版)》2002,18(4):727-736
Let {W(t); t≥ 0} be a standard Wiener process and S be the Strassen set of functions. We investigate the exact rates of convergence to zero (as T→∞) of the variables $ \sup _{{0 \leqslant t \leqslant T - \alpha _{T} }} \inf _{{f \in S}} \sup _{{0 \leqslant x \leqslant 1}} {\left| {Y_{{t,T}} {\left( x \right)} - f{\left( x \right)}} \right|} Let {W(t); t≥ 0} be a standard Wiener process and S be the Strassen set of functions. We investigate the exact rates of convergence to zero (as T→∞) of the variables sup0≤
t
≤
T
−
aT
inf
f∈S
sup0≤
x
≤1|Y
t,T
(x) −f(x)| and inf0≤
t
≤
T−aT
sup0≤
x
≤1|Y
t,T
(x−f(x)| for any given f∈S, where Y
t,T
(x) = (W(t+xa
T
) −W(t)) (2a
T
(log Ta
T
−1 + log log T))−1/2.
We establish a relation between how small the increments are and the functional limit results of Cs?rg{\H o}-Révész increments
for a Wiener process. Similar results for partial sums of i.i.d. random variables are also given.
Received September 10, 1999, Accepted June 1, 2000 相似文献
942.
Experiments were carried out on arrays of chaotic electrochemical oscillators to which global coupling, periodic forcing, and feedback were applied. The global coupling converts a very weakly coupled set of chaotic oscillators to a synchronized state with sufficiently large values of coupling strength; at intermediate values both intermittent and stable chaotic cluster states occur. Cluster formation and synchronization were also obtained by applying feedback and forcing to a moderately coupled base state. The three cases differ, however, in other details. The feedback and forcing also produce periodic cluster states and more than two clusters. Configurations of two (chaotic) clusters and two, three, or four (periodic) clusters were observed. (c) 2002 American Institute of Physics. 相似文献
943.
944.
Bifurcation characteristics of a nonlinear system can be manipulated by small controls. In this paper, we present a control method to create Hopf bifurcations in discrete-time nonlinear systems. The critical conditions for the Hopf bifurcations are discussed. The center manifold method, normal form technique and the Iooss's Hopf bifurcation theory are employed in the derivation of the control gain. Numerical demonstration is provided. (c) 2002 American Institute of Physics. 相似文献
945.
Poly (3-alkylthiophenes) (P3ATs) have made up of a family of conductive polymerswhich are soluble, fusible and processable, since the introduction of flexible alkyl sidechains"'. It is generally accepted that P3ATs can form similar layered structures. inwhich the thiophene rings possess planarity and the side chains act as spacers'-'. Whenthe number. of 'carbon atoms of alkyl side chains is more than 10, some orderlyarrangements will occur for side chains betWeen the' layers'. It has been w… 相似文献
946.
研究一类三阶自治系统的积分方法,证明了在一定条件下,这类系统的积分问题归结为求解由该方程的系数所确定的Riccati方程 相似文献
947.
集对Fuzzy格及其在格表示论中的应用 总被引:1,自引:0,他引:1
用幂集格构造了集对 Fuzzy 格(这与用整数对构造有理数集有相似之处),并用它证明了完整的软代数表示定理,即定义了到自身的映射且有最大元和最小元的格为软代数的充要条件是它与某个集对 Fuzzy 格的子格同构.这样,与分配格在幂集 Boole 格中表示相对应,软代数在集对 Fuzzy 格中有表示,在理论上是很完美的 相似文献
948.
PHASE SEPARATION AND JOSEPHSON-COUPLING ORIGIN FOR THE ANOMALOUS Hc2 BEHAVIOR IN OVERDOPED Bi2Sr2-xLaxCuO6+δ CRYSTALS
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Hole-overdoped Bi2Sr2-xLaxCuO6+δ single crystals with two coexistent superconducting transitions have been intensively studied by measuring the dc magnetic susceptibility. It is found that the coexistence of these two phases cannot be attributed to any chemical or vortex dynamical effect but to some intrinsic driving force, such as the electronic-driven phase separation. Furthermore, the upper critical fields of the two phases behave in a rather different way; that is, one of them shows a "normal Hc2 behavior" which can be described by the critical fluctuation theory, while the other exhibits an "anomalous Hc2 behavior" and can be well explained by a recent theory based on an assumption of a Josephson-coupling origin, indicating a strong evidence of Josephson-coupling origin for the upward curvature of the so-called Hc2 in high Tc superconductors. 相似文献
949.