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本文研究纯正的群的正则带.在给出这类半群的若干特征后,建立了纯正的群的正则带的构造定理.作为应用,同时给出了纯正的群的右拟正规带的构造定理. 相似文献
954.
重尾平稳序列的大偏差 总被引:3,自引:0,他引:3
本文给出了一类重尾的随机变量序列{Xn,n≥1}的部分和Sn=∑i=1 n Xi与随机和S(t)=∑i=1^N(t) Xi的大偏差结果其中{N(t),t≥)}是一族非负整值的随机变量,{Xn,n≥1}是非负的平稳过程,并且与{N(t),t≥0}独立。本文将独立同分布情形的结果掖到了平稳相依的情形。 相似文献
955.
给出了超球级数所定义整函数的下阶、下型与极大项、中心指标、最大模之间的关系及几个不等式,并由此推出了超球级数成正规增长的充要条件及成完全正规增长的充要条件. 相似文献
956.
We study the amply regular diameter d graphs Γ such that for some vertex a the set of vertices at distance d from a is the set of points of a 2-design whose set of blocks consists of the intersections of the neighborhoods of points with the set of vertices at distance d-1 from a. We prove that the subgraph induced by the set of points is a clique, a coclique, or a strongly regular diameter 2 graph. For diameter 3 graphs we establish that this construction is a 2-design for each vertex a if and only if the graph is distance-regular and for each vertex a the subgraph Γ3(a) is a clique, a coclique, or a strongly regular graph. We obtain the list of admissible parameters for designs and diameter 3 graphs under the assumption that the subgraph induced by the set of points is a Seidel graph. We show that some of the parameters found cannot correspond to distance-regular graphs. 相似文献
957.
An automatic sampling device, i.e., process sampling module (PSM), connected with a purge and trap-GC-FID system has been developed for real-time monitoring of VOCs in wastewater. The system was designed to simultaneously monitor 17 compounds, including one polar compound, i.e., acetone, and 16 non-polar compounds. The trapping tube is packed with two adsorbents, Carbopack B and Carbosieve III, to trap target compounds. For the purpose of in situ monitoring, the flush valve of the sampling tube is composed of two two-way valves and a time controller to prevent absorption interference of the residue. The optimal conditions for the analytical system include a 12 min purge time at a temperature of 60 °C, and 4 min of desorption time with a desorption temperature of 260 °C. Good chromatograms have been obtained with the analytical system even if a cryogenic device and de-misting were not used. The relative standards deviation (RSD) of the system is between 2% and 13.4%, and accuracies between 0.3 and 23.5% have been achieved. The detection limits of the method range from 0.32 to 2.39 ppb. In this system, the four parts, i.e., PSM, P&T, GC, and FID, were simple, reliable and rugged. Also, the interface of these four parts was simple and dependable. 相似文献
958.
At high spatial dimension, a suitably scaled classical system of interacting particles truncates at second virial terms. A binary mixture of nonadditive hard spheres with sufficiently repulsive interaction between unlike particles decomposes at sufficiently high density into two coexisting phases. The region around the critical density behaves classically. 相似文献
959.
介绍一种飞行器火力控制系统驾驶员显示组件中光学组件的设计思想,并根据其使用特点,论述用在像面上点列分布“锐度”及细光束点列分布“锐度”的像质评价方法。 相似文献
960.
Kalishin E. Yu. Khavrus' V. A. Goncharenko M. M. Ivashchenko T. S. Strizhak P. E. 《Theoretical and Experimental Chemistry》2002,38(6):375-380
The effect of manganese(II) ions on the asymptotically regular self-oscillation regime of the Belousov–Zhabotinskii reaction, catalysed by ferroin, in a tank reactor with constant stirring has been studied. An increase in the manganese(II) ion concentration in the system leads to an increase in the period of the self-oscillations. The sensitivity of the self-oscillation of the chemical reaction on the addition of Mn2+ ions is decreased with an increase in acidity. To explain the results obtained we have used a reversible Oregonator model, which is supplemented with reactions between manganese(II) and manganese(III) ions and bromoxyl radicals, malonic acid, and ferroin. 相似文献