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排序方式: 共有1085条查询结果,搜索用时 62 毫秒
961.
研究和宣传新思想的报刊的大量出现,以及发表在<浙江新潮>上<非孝>一文引发的"一师风潮",是五四运动影响浙江思想界与报刊界的直接后果."一师风潮"是1920年全国学生运动中最突出的事件之一,<浙江新潮>则对新思想在浙江的传播起了很大的作用.  相似文献   
962.
以石武客专P60 1/18板式无砟高速道岔安装施工为背景,介绍了P60 1/18板式无砟高速道岔安装及精调的过程。详细论述了道岔安装前的准备工作, 道岔安装的工艺流程,精调时采取的步骤,调整时均应遵循的原则并满足的要求,道岔焊接应注意的事项。对类似板式无砟高速道岔安装具有指导意义。  相似文献   
963.
The Barrodale and Roberts algorithm for least absolute value (LAV) regression and the algorithm proposed by Bartels and Conn both have the advantage that they are often able to skip across points at which the conventional simplex-method algorithms for LAV regression would be required to carry out an (expensive) pivot operation.

We indicate here that this advantage holds in the Bartels-Conn approach for a wider class of problems: the minimization of piecewise linear functions. We show how LAV regression, restricted LAV regression, general linear programming and least maximum absolute value regression can all be easily expressed as piecewise linear minimization problems.  相似文献   
964.
This article discusses testing hypotheses and confidence regions with correct levels for the mean sojourn time of an M/M/1 queueing system. The uniformly most powerful unbiased tests for three usual hypothesis testing problems are obtained and the corresponding p values are provided. Based on the duality between hypothesis tests and confidence sets, the uniformly most accurate confidence bounds are derived. A confidence interval with correct level is proposed.  相似文献   
965.
In this article, maximum likelihood estimator (MLE) as well as Bayes estimator of traffic intensity (ρ) in an M/M/1/∞ queueing model in equilibrium based on number of customers present in the queue at successive departure epochs have been worked out. Estimates of some functions of ρ which provide measures of effectiveness of the queue have also been derived. A comprehensive simulation study starting with the transition probability matrix has been carried out in the last section.  相似文献   
966.
ABSTRACT

A bivariate integer-valued autoregressive time series model is presented. The model structure is based on binomial thinning. The unconditional and conditional first and second moments are considered. Correlation structure of marginal processes is shown to be analogous to the ARMA(2, 1) model. Some estimation methods such as the Yule–Walker and conditional least squares are considered and the asymptotic distributions of the obtained estimators are derived. Comparison between bivariate model with binomial thinning and bivariate model with negative binomial thinning is given.  相似文献   
967.
968.
《随机性模型》2013,29(2):201-233
In this paper, we study transition matrices of GI/M/1 type by using the approach proposed in Li and Zhao.[13] Li, Q.L. and Zhao, Y.Q. 2002. “A constructive method for finding β-invariant measures for transition matrices of M/G/1 type”. In Matrix-Analytic Methods Theory and Applications 237263. New Jersey: World Scientific. [Crossref] [Google Scholar] We obtain conditions on the α-classification of states for the transition matrix of GI/M/1 type. Unlike for matrices of M/G/1 type where association of the matrix multiplication can be easily justified, for matrices of GI/M/ type, we first construct formal expressions for the β-invariant measure based on a representation of factorization of the transition matrix, and then show that it is a β-invariant measure directly. We also prove some spectral properties for the matrix of GI/M/1 type, which are not only used in constructing a formal expression for the β-invariant measure, but also of their own interest. We point out that the spectral analysis required for studying matrices of GI/M/1 type is much more sophisticated than that for matrices of M/G/1 type. Finally, we discuss connections of expressions for the β-invariant measure provided in this paper and in the literature.  相似文献   
969.
《随机性模型》2013,29(2-3):485-505
ABSTRACT

We study the queue length distribution of a queueing system with BMAP arrivals under D-policy. The idle server begins to serve the customers only when the sum of the service times of all waiting customers exceeds some fixed threshold D. We derive the vector generating functions of the queue lengths both at a departure and at an arbitrary point of time. Mean queue lengths are derived and a numerical example is presented.  相似文献   
970.
WISCHE: A DSS for water irrigation scheduling   总被引:1,自引:0,他引:1  
In this paper we present the models and the algorithms which are being used in a decision support system (DSS) to determine water irrigation scheduling. The DSS provides dynamic scheduling of the daily irrigation for a given land area by taking into account the irrigation network topology, the water volume technical conditions and the logistical operations. The system has been validated by the Agriculture Community of Elche (Spain) and annexed to their Supervisory Control and Data Acquisition system (SCADA). We present two heuristic approaches to solve the mixed 0–1 separable nonlinear program for irrigation scheduling implemented with free software.  相似文献   
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