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排序方式: 共有1379条查询结果,搜索用时 500 毫秒
81.
尤晨 《数学的实践与认识》2014,(20)
现实中许多抽象系统的数值并不能精确地得到,在多属性决策过程中,其属性值多以模糊数或者区间灰数的形式表示,属性权重也受到主观因素和客观因素的影响,针对此类问题,以属性值为区间灰数的多属性决策问题为出发点,采用主客观结合的赋权方式,提出了基于区间距离的灰色相对关联度分析方法,构建了灰色决策模型,并通过消费者决策实例进行了分析,模型是对传统灰色决策模型的拓展,具有更广泛的应用性和实用性. 相似文献
82.
The control of flow in a tundish is important for improving the quality of the steel. Dams, Wiers and Pouring chamber are some of the devices used for controlling the flow in the tundish. The investigation about the role of electromagnetic forces as a replacement for these devices is an objective for the present work. Thus, 3-D MHD simulation was performed to study the effect of electromagnetic forces on flow behaviour in the tundish. The MHD model developed for carrying out the simulation was validated with the analytical solution of the Hartman problem. The results obtained shows improvement in the desired characteristics for inclusion flotataion with magnetic flow modifier of optimum strength of magnetic field. 相似文献
83.
Harmonic force fields are developed for the Ga2Br6 and Ga2I6 molecules. The analysis confirms previous assignments of experimental frequencies. Mean amplitudes of vibration are calculated. 相似文献
84.
《复变函数与椭圆型方程》2012,57(6):495-505
If the dilatation tensor or the matrix dilatation of a quasiconformal mapping $ f\!:\! G\to {\bf R} ^ n $ belongs to the space VMO of functions with vanishing mean oscillation, then f is locally Hölder continuous with every exponent f < 1. 相似文献
85.
By the explicit representation for the divided differences with repetitions involving cycle index of symmetric groups, this paper deals with the asymptotic behavior of the intermediate point of the mean value theorem of divided differences with repetitions. Our results generalize some recent interesting results such as the asymptotic expansions of the immediate points of the Taylor formula and the differential mean value theorem of divided differences with distinct points. 相似文献
86.
The estimation of the variance of point estimators is a classical problem of stochastic simulation. A more specific problem addresses the estimation of the variance of a sample mean from a steady-state autocorrelated process. Many proposed estimators of the variance of the sample mean are parameterized by batch size. A critical problem is to find an appropriate batch size that provides a good tradeoff between bias and variance. This paper proposes a procedure for determining the optimal batch size to minimize the mean squared error of estimators of the variance of the sample mean. This paper also presents the results of empirical studies of the procedure. The experiments involve symmetric two-state Markov chain models, first-order autoregressive processes, seasonal autoregressive processes, and queue-waiting times for several M/M/1 queueing models. The empirical results indicate that the estimation procedure works nearly as well as it would if the parameters of the processes were known. 相似文献
87.
The present paper deals with the problem of calculating mean delays in polling systems with either exhaustive or gated service.
We develop a mean value analysis (MVA) to compute these delay figures. The merits of MVA are in its intrinsic simplicity and
its intuitively appealing derivation. As a consequence, MVA may be applied, both in an exact and approximate manner, to a
large variety of models. 相似文献
88.
Hiroshi Shibata 《Physica A》1998,260(3-4)
Disorderness of spatiotemporal patterns which are obtained by nonlinear partial differential equations is characterized quantitatively. The mean Lyapunov exponent for a nonlinear partial differential equation is given. The local Lyapunov exponent which is a finite time average of the mean Lyapunov exponent is shown to have close relation to the spatiotemporal patterns. It is suggested that the systems which are described by nonlinear partial differential equations are characterized statistically through the probability distribution function of the local Lyapunov exponent. 相似文献
89.
三维 Anti-de Sitter空间中常平均曲率旋转曲面 总被引:3,自引:1,他引:2
本文主要构造三维 Anti-de Sitter空间中单参数族的常平均曲率旋转曲面. 相似文献
90.
金明鸥 《数学的实践与认识》2007,37(11):88-91
将灰关联分析方法应用于医院管理年活动中,分析了影响医疗服务质量的相关因素,并对医院医疗服务质量进行综合评价. 相似文献