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941.
G表示局部紧的Vilenkin群, 在论文中作者将研究某些次线性算子和Calderón Zygmund算子在Herz型Hardy空间上的有界性.   相似文献   
942.
1.引言 由于高性能并行计算机的出现和并行计算的推动,十多年来,抛物型方程有限差分并行算法设计与分析一直受到关注. D.J.Evalns和A.R.B.Abdullah(1983,[1,2]利用Saul’yev非对称格式对常系数抛物方程设计了AGE(交替分组显格式)算法,并用矩阵分析的方法证明了该算法的无条件稳定性.该算法有明显的并行性,倍受推崇,且计算的实践([8],[9])表明它对变系数的抛物方程也是可行的,但稳定性的分析成为一个难点.张宝琳([3])在一维情  相似文献   
943.
We study a quantum chain of oscillators with nonlinear quartic interactions, under the “narrow packet” approximation. We analyse the dynamics of quantum corrections and the conditions at which the quantum solution for average complex amplitude converges to the corresponding classical unstable solution which describes the four-wave decay processes of phonons. We develop an asymptotic theory by using a small quasiclassical parameter, and determine the characteristic time scale for which the evolution of decay processes is essentially specified by quantum effects. AMS Subject classification: Primary: 35F10 Secondary: 35Q40, 35B40  相似文献   
944.
本文利用嵌入马尔可夫链方法研究了多重休假M^X/Gn/1排队系统。首先,利用概率分析法得到了排队系统的嵌入马尔可夫链的一步转移概率矩阵,以此为依据得到系统的稳态队长和同批第一个接受服务顾客的稳态等待时间。  相似文献   
945.
We present a coupled decreasing sequence of random walks on Z that dominate the edge process of oriented bond percolation in two dimensions. Using the concept of random walk in a strip, we describe an algorithm that generates an increasing sequence of lower bounds that converges to the critical probability of oriented percolation pc. From the 7th term on, these lower bounds improve upon 0.6298, the best rigorous lower bound at present, establishing 0.63328 as a rigorous lower bound for pc. Finally, a Monte Carlo simulation technique is presented; the use thereof establishes 0.64450 as a non-rigorous five-digit-precision (lower) estimate for pc. Mathematics Subject Classification (1991): 60K35 Supported by CNPq (grant N.301637/91-1). Supported by a grant from CNPq.  相似文献   
946.
基于径向基函数神经网络的流程企业供应链预测仿真   总被引:2,自引:1,他引:1  
李自如  边利  邓建 《运筹与管理》2006,15(1):152-155
本文在比较预测方法的基础上,采用径向基函数(RBF)神经网络技术建立流程企业供应链预测模型,进行了实例预测仿真,并将预测结果与BP网络的预测结果进行了比较。结果表明,RBF网络误差小于BP网络,其中平方根RBF网络的预测仿真误差最小,而BP网络的误差最大。  相似文献   
947.
Hydroxyl chain‐end functionalizations of polymeric organolithium compounds with oxetane (trimethylene oxide) were studied in benzene at 25 °C. Functionalizations of poly(styryl)lithium and polystyrene‐oligo‐butadienyllithium proceed efficiently to form the corresponding ω‐hydroxypropyl‐functionalized polymers in 98 and 97% isolated yields, respectively. No nonfunctional polymer (≤1–2%) was detected by thin layer chromatography (TLC) analysis for either polymer. All functionalized polymers were characterized by 13C and 1H NMR analyses; no evidence for oxetane oligomerization at the chain end was observed. The MALDI‐TOF mass spectrum of ω‐hydroxypropylpolystyrene was consistent with the expected structure without any detectable oligomerization of oxetane. A small, but detectable series of peaks corresponding to nonfunctional polystyrene was also observed in the MALDI‐TOF mass spectrum. The functionalization of the adduct of 1,1‐diphenylethylene and PSLi produced the corresponding ω‐hydroxypropyl‐functionalized polymer in only 86% isolated yield. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2684–2693, 2006  相似文献   
948.
Consecutive-(r,f,k)-out-of-n:F系统由n个单元顺序连结而成,仅当在连续的r个单元中,至少有f个失效或者至少连续k个失效,整个系统才失效;而Consecutive-(f,g)-out-of-(r,n):F系统由n个单元顺序连结而成,仅当在整个系统中至少有f个失效或者在连续的r个单元中,至少有g个失效,整个系统才失效。本文运用马氏链嵌入方法,在单元之间相互独立以及单元之间马氏相关这两种情况下,给出线性系统的可靠性。  相似文献   
949.
A new theory to predict the molecular weight distribution in free radical polymerization that includes chain transfer to polymer is proposed. This theory is based on the branching density distribution of the primary polymer molecules. The branching density distribution provides the information on how each chain is connected to other chains, and therefore, a full molecular weight distribution can be calculated by application of the Monte Carlo simulation. The present theory accounts for the history of the generated branched structure and can be applied to various reaction systems that involve branching and crosslinking regardless of the reactor types used. The present simulation confirmed the validity of the method of moments in a batch polymerization proposed earlier. It was shown clearly why gelation never occurs by chain transfer to polymer without the assistance of other interlinking reaction such as bimolecular termination by combination. © 1993 John Wiley & Sons, Inc.  相似文献   
950.
The aim of this paper is to present an online economical quality-control procedure for attributes in a process subject to quality deterioration after random shift and misclassification errors during inspections. The process starts in control (State I) and, in a random time, it shifts to out of control (State II). Once at State II, the non-conforming fraction increases according to a non-decreasing function ψ(z), where z is the number of items produced after a shift. The monitoring procedure consists of inspecting a single item at every m produced items, which is examined r times independently to decide its condition. Once an inspected item is declared non-conforming, the process is stopped and adjusted. A direct search technique is used to find the optimum parameters which minimize the expected cost function. The proposed model is illustrated by a numerical example. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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