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991.
该文利用Krasnoselskii不动点定理,讨论了一阶混合中立型微分方程[x(t)-cx(t-h)-c^*x(t+h^*)]'=p(t)x(g(t)),获得了方程在p\leq p(t)<0与0
相似文献
992.
This paper is concerned with properties of the wave speed for the stochastically perturbed Fisher–Kolmogorov–Petrovsky–Piscunov
(FKPP) equation. It was shown in the classical 1937 paper by Kolmogorov, Petrovsky and Piscunov that the large time behavior
of the solution to the FKPP equation with Heaviside initial data is a travelling wave. In a seminal 1995 paper Mueller and
Sowers proved that this also holds for a stochastically perturbed FKPP equation. The wave speed depends on the strength σ
of the noise. In this paper bounds on the asymptotic behavior of the wave speed c(σ) as σ→0 and σ→∞ are obtained. 相似文献
993.
Francisco J. Aragón Artacho 《Set-Valued Analysis》2007,15(3):307-315
Borwein’s norm duality theorem establishes the equality between the outer (inner) norm of a sublinear mapping and the inner
(outer) norm of its adjoint mappings. In this note we provide an extended version of this theorem with a new and self-contained
proof relying only on the Hahn-Banach theorem. We also give examples showing that the assumptions of the theorem cannot be
relaxed.
This author is supported by Grant BES-2003-0188 from FPI Program of MEC (Spain). 相似文献
994.
本文采用了Gengsheng和Min(2003)提出的经验似然方法,基于一个新的方程对中值回归模型的参数进行统计推断,数值模拟的结果表明,本文所得到的参数估计结果比Gengsheng和Min(2003)的模拟结果更精确. 相似文献
995.
Semion I. Kuchanov Konstantin V. Tarasevich Timur V. Zharnikov 《Journal of statistical physics》2006,122(5):875-908
The statistical theory of gelation in the simplest process of the non-random polycondensation (S. I. Kuchanov, T. V. Zharnikov,
J. Stat. Phys., 111(5/6), 1273 (2003)) has been refined as to be able to take into account the effect of a monomer configuration
on topological characteristics of the polymer network of the gel. Proceeding from the kinetic analysis of such a polycondensation,
we rigorously prove that it can be described in terms of some stochastic branching process. The parameters of the process
depend on the overall number of functional groups in the monomer as well as on the pattern of their mutual arrangement. Examples
of some model systems illustrate the effect of kinetic and configurational factors on the topology of a polymer network formed
in the course of non-random polycondensation. 相似文献
996.
Bouchra Lamrini Marie-Vronique Le Lann Ahmed Benhammou El Khadir Lakhal 《Comptes Rendus Physique》2005,6(10):1161-1168
The present Note proposes a learning classification methodology to identify functional states on a coagulation process involved in drinking water treatment. In this work, we chose to carry out the supervised control of this process while using the LAMDA (Learning Algorithm for Multivariate Data Analysis) classification technique. The LAMDA classification technique proposes the interactive participation of the expert operator during the learning phase and in the optimisation of the classification. In this work, all information stemming from the environment process as well as expert knowledge has been aggregated and exploited. The application chosen for state identification is the Rocade drinking water treatment plant located at Marrakech, Morocco. To cite this article: B. Lamrini et al., C. R. Physique 6 (2005). 相似文献
997.
Joshua Rushton 《Journal of Theoretical Probability》2007,20(3):397-427
We establish a functional LIL for the maximal process M(t) :=sup 0≤s≤t
‖X(s)‖ of an ℝ
d
-valued α-stable Lévy process X, provided X(1) has density bounded away from zero over some neighborhood of the origin. We also provide a broad invariance result governing
a class independent-increment processes related to the domain of attraction of X(1). This breadth is particularly notable for two types of processes captured: First, it not only describes any partial sum
process built from iid summands in the domain of normal attraction of X(1), but also addresses those with arbitrary iid summands in the full domain of attraction (here we give a technical condition
necessary and sufficient for the partial sum process to share the exact LIL we prove for X). Second, it reveals that any Lévy process L such that L(1) satisfies the technical condition just mentioned will also share the LIL of X.
Supported in part by NSF Grant DMS 02-05034. 相似文献
998.
This paper is concerned with the distributional properties of a median unbiased estimator of ARCH(0,1)coefficient.The exact distribution of the estimator can be easily derived,however its practical calculations are too heavy to implement, even though the middle range of sample sizes.Since the estimator is shown to have asymptotic normality,asymptotic expansions for the distribution and the percentiles of the estimator are derived as the refinements.Accuracies of expansion formulas are evaluated numerically,and the results of which show that we can effectively use the expansion as a fine approximation of the distribution with rapid calculations.Derived expansion are applied to testing hypothesis of stationarity,and an implementation for a real data set is illustrated. 相似文献
999.
Inneke Van Nieuwenhuyse Nico Vandaele Kumar Rajaram Uday S. Karmarkar 《European Journal of Operational Research》2007
This paper studies the impact of management policies, such as product allocation and campaign sizing, on the required size of the finished goods inventories in a multi-product multi-reactor batch process. Demand, setup and batch processing times for these products are assumed to be stochastic, and the inventory buffer for every product type needs to be such that target customer service levels are met. To perform this analysis, we develop a queueing model that allows us to explicitly estimate service levels as a function of the buffer size, and the allocation/campaign sizing policies. This model can be used to evaluate the service level given an existing buffer configuration, as well as to determine the buffer sizes required across products to meet a pre-specified service level. It also allows us to formulate a number of insights into how product allocation decisions and campaign planning policies affect buffer sizing decisions in symmetric production systems. 相似文献
1000.
Yoichi Miyazaki 《Journal of Differential Equations》2003,188(2):555-568
We consider the strongly elliptic operator A of order 2m in the divergence form with bounded measurable coefficients and assume that the coefficients of top order are uniformly continuous. For 1<p<∞, A is a bounded linear operator from the Lp Sobolev space Hm,p into H−m,p. We will prove that (A−λ)−1 exists in H−m,p for some λ and estimate its operator norm. 相似文献