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201.
Let I = [0, 1], c 1, c 2 ∈ (0, 1) with c 1 < c 2 and f : II be a continuous map satisfying: are both strictly increasing and is strictly decreasing. Let A = {x ∈ [0, c 1]∣f(x) = x}, a=max A, a 1 =max(A\{a}), and B = {x ∈ [c 2, 1]∣f(x) = x}, b=minB, b 1 =min(B\{b}). Then the inverse limit (I, f) is an arc if and only if one of the following three conditions holds: (1) If c 1 < f (c 1) ≤ c 2 (resp. c 1f (c 2) < c 2), then f has a single fixed point, a period two orbit, but no points of period greater than two or f has more than one fixed point but no points of other periods, furthermore, if Aφ and Bφ, then f (c 2) > a (resp. f (c 1) < b). (2) If f (c 1) ≤ c 1 (resp. f (c 2) ≥ c 2), then f has more than one fixed point, furthermore, if Bφ and A\ {a} ≠φ, f (c 2) ≥ a or if a 1 < f (c 2) < a, f 2 (c 2) > f (c 2), (resp. f has more than one fixed point, furthermore, if Aφ and B\{b}≠φ, f (c 1) ≤ b or if b < f (c 2) < b 1, f 2 (c 1) < f (c 1)). (3) If f (c 1) > c 2 and f (c 2) < c 1, then f has a single fixed point, a single period two orbit lying in I\(u, v) but no points of period greater than two, where u, v ∈ [c 1, c 2] such that f (u) = c 2 and f (v) = c 1. Supported by the National Natural Science Foundation of China (No. 19961001, No. 60334020) and Outstanding Young Scientist Research Fund. (No. 60125310)  相似文献   
202.
We obtain an almost sure central limit theorem (ASCLT) for heavily trimmed sums. We also prove a function-typed ASCLT under the same conditions that assure measurable functions to satisfy the ASCLT for the partial sums of i.i.d, random variables with E X1 = 0, EX1^2 = 1.  相似文献   
203.
A method allowing subwavelength resolution within the framework of optical interferometric microscopy is proposed. It is shown that overcoming the diffraction limit is not a necessary requirement. Generally speaking, subrayleigh resolution and overcoming the diffraction limit are basically different concepts. The method developed uses the all-parameter modulation of the light source and separation of the phase shifts generated due to different reasons. In this method, a topological phase technique is used to separate the phases and therefore determine the corresponding characteristics of an object. The approach developed provides for a way to create a new type of optical devices. Within the framework of a uniform measuring procedure these devices make possible determining both geometrical and material parameters of the object under study.  相似文献   
204.
Let V n –1 n be the adaptive process of self-normalized partial sums S k of independent random variables X i , defined by linear interpolation between the points (V k 2/V n 2,S k /V n ), kn, where V k 2= ik X i 2. We prove that if the X k 's are symmetric, V n –1 n converges weakly to the Brownian motion W in each Hölder space supporting W if and only if V n –1 max kn |X k |=o P (1). We give some partial extension to the non symmetric case.  相似文献   
205.
P. Kabaila 《Acta Appl Math》2003,78(1-3):185-192
We consider the problem of constructing a 1– upper confidence limit for the scalar parameter 0 in the presence of the nuisance parameter vector 0, when the data are discrete. The 'profile plug-in' upper confidence limit is introduced by Kabaila and Lloyd. This confidence limit is based on computing a P-value from an estimator of 0, replacing the nuisance parameter by the profile maximum likelihood estimate for known, and equating to . Theoretical and numerical evidence for the good coverage properties of this confidence limit is presented by Kabaila and Lloyd. An upper confidence limit should be assessed not only by its coverage properties but also by how large this confidence limit is. We measure how large the profile plug-in upper limit is by using a large sample approximation to it. This large sample approximation is used to delineate further the good properties of this confidence limit.  相似文献   
206.
We prove laws of large numbers for a second class particle in one-dimensional totally asymmetric -exclusion processes, under hydrodynamic Euler scaling. The assumption required is that initially the ambient particle configuration converges to a limiting profile. The macroscopic trajectories of second class particles are characteristics and shocks of the conservation law of the particle density. The proof uses a variational representation of a second class particle, to overcome the problem of lack of information about invariant distributions. But we cannot rule out the possibility that the flux function of the conservation law may be neither differentiable nor strictly concave. To give a complete picture we discuss the construction, uniqueness, and other properties of the weak solution that the particle density obeys.

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207.
We derive lower bounds for Lp norms , in the central limit theorem for independent and m–dependent random variables with finite fifth order absolute moments and for independent and m–dependent identically distributed random variables with fourth order moments.  相似文献   
208.

Let be the Weinstein operator on the half space, . Suppose there is a sequence of Borel sets such that a certain tangential projection of onto forms a pairwise disjoint subset of the boundary. Let be a finite test measure on the boundary for a specific non-isotropic Hausdorff measure. The measure is carried back to a measure on a subset of by the projection. We give an upper bound for the Weinstein potential corresponding to the measure in terms of a universal constant and a Weinstein subharmonic function. We use this upper bound to deduce a result concerning tangential behavior of Weinstein potentials at the boundary with the exception of sets on the boundary of vanishing non-isotropic Hausdorff measure.

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209.
Semiuniform convergence spaces form a common generalization of filter spaces (including symmetric convergence spaces [and thus symmetric topological spaces] as well as Cauchy spaces) and uniform limit spaces (including uniform spaces) with many convenient properties such as cartesian closedness, hereditariness and the fact that products of quotients are quotients. Here, for each semiuniform convergence space a completion is constructed, called the simple completion. This one generalizes Császár's -completion of filter spaces. Thus, filter spaces are characterized as subspaces of convergence spaces. Furthermore, Wyler's completion of separated uniform limit spaces can be easily derived from the simple completion.  相似文献   
210.
Langford系统Hopf分叉的线性反馈控制   总被引:3,自引:0,他引:3       下载免费PDF全文
刘素华  唐驾时 《物理学报》2007,56(6):3145-3151
分析Langford系统的Hopf分叉现象,并研究采用线性反馈控制方法控制该系统的Hopf分叉.从理论上推导出受控系统产生Hopf分叉的条件,给出了某些极限环的解析表达式,对该系统进行了分叉点的转移与极限环的稳定性控制.数值模拟说明本文采用的方法对Langford系统的Hopf分叉控制是有效的. 关键词: Langford系统 反馈控制 Hopf分叉 极限环  相似文献   
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