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排序方式: 共有493条查询结果,搜索用时 9 毫秒
1.
谈音长在教学和修辞中的作用   总被引:1,自引:0,他引:1  
语言是声音和意义的结合体。语音是语言的物质外壳。语音的音长决定着言语的速度 ,在交际中 ,对内容的表达起积极作用 ,在教学和修辞的语言实践中 ,应重视音长的作用。  相似文献   
2.
The maximum likelihood estimation for the critical points of the failure rate and the mean residual life function are presented in the case of mixture inverse Gaussian model. Several important data sets are analyzed from this point of view. For each of the data sets, Bootstrapping is used to construct confidence intervals of the critical points.  相似文献   
3.
知识通过网络可以加快扩散.作者基于NW小世界网络视角,构建高技术企业联盟知识扩散模型,揭示联盟的知识扩散特性,并运用MATLAB软件进行模拟仿真.研究发现,减小网络的特征路径长度、增大网络的集聚系数和提高成员间的知识交流频率是促进高技术企业联盟知识扩散、提高创新效率、加快知识创新的有效途径.  相似文献   
4.
In this paper we investigate the asymptotic critical value behaviour of certain multiple decision procedures as e.g. simultaneous confidence intervals and simultaneous as well as stepwise multiple test procedures. Supposing that n hypotheses or parameters of interest are under consideration we investigate the critical value behaviour when n increases. More specifically, we answer e.g. the question by which amount the lengths of confidence intervals increase when an additional parameter is added to the statistical analysis. Furthermore, critical values of different multiple decision procedures as for instance step-down and step-up procedures will be compared. Some general theoretic results are derived and applied for various distributions.  相似文献   
5.
We interpret gradients in population dynamics of the gray-sided vole from the southwestern part of the island of Hokkaido to its northeastern part within the framework of a phenomenological model involving the relative length of summer and winter. In Hokkaido, as in other northern regions, both spring and fall is considered as short transition periods between the two main seasons — summer (the primary breeding season) and winter (the non-reproductive or secondary breeding season). We show that the geographic transition in dynamics may be understood as the combined consequence of different patterns of density-dependence during summer and winter, and geographically varying season lengths. Differences are shown to exist between summer and winter with respect to strength of density-dependence. Direct density-dependence, in particular, is stronger during winter than during summer. A model is presented to show how relative lengths of seasons can induce both stable and periodically fluctuating population dynamics. The results are compared and contrasted with what is otherwise known about the gradient in rodent dynamics in Fennoscandia.  相似文献   
6.
In this article, Six Sigma zone control charts (SSZCCs) are proposed for world class organizations. The transition probabilities are obtained using the Markov chain approach. The Average Run Length (ARL) values are then presented. The ARL performance of the proposed SSZCCs and the standard Six Sigma control chart (SSCC) without zones or run rules is studied. The ARL performance of these charts is then compared with those of the other standard zone control charts (ZCCs), the modified ZCC and the traditional Shewhart control chart (SCC) with common run rules. As expected, it is shown that the proposed SSZCC outperforms the standard SSCC without zones or run rules for process shifts of any magnitude. When compared to the other standard ZCCs and the Shewhart chart with common run rules, it is observed that the proposed SSZCCs have much higher false alarm rates for smaller shifts and hence they prevent unwanted process disturbances. The application of the proposed SSZCC is illustrated using a real time example.  相似文献   
7.
Control charts are effective tools for signal detection in both manufacturing processes and service processes. Much service data come from a process with variables having nonnormal or unknown distributions. The commonly used Shewhart variable control charts, which depend heavily on the normality assumption, should not be properly used here. In this article, we propose an improved asymmetric EWMA mean chart based on a simple statistic to monitor process mean shift. We explored the sampling properties of the new monitoring statistic and calculated the average run lengths of the proposed asymmetric EWMA mean chart. We recommend the proposed improved asymmetric EWMA mean chart because the average run lengths of the modified charts are more accurate and reasonable than those of the five existed mean charts. A numerical example of service times with a right skewed distribution from a service system of a bank branch is used to illustrate the application of the improved asymmetric EWMA mean chart and to compare it with the five existing mean charts. The proposed chart showed better detection performance than those of the five existing mean charts in monitoring and detecting shifts in the process mean.  相似文献   
8.
The memory-type adaptive and non-adaptive control charts are among the best control charts for detecting small-to-moderate changes in the process parameter(s). In this paper, we propose the Crosier CUSUM (CCUSUM), EWMA, adaptive CCUSUM (ACCUSUM) and adaptive EWMA (AEWMA) charts for efficiently monitoring the changes in the covariance matrix of a multivariate normal process without subgrouping. Using extensive Monte Carlo simulations, the length characteristics of these control charts are computed. It turns out that the ACCUSUM and AEWMA charts perform uniformly and substantially better than the CCUSUM and EWMA charts when detecting a range of shift sizes in the covariance matrix. Moreover, the AEWMA chart outperforms the ACCUSUM chart. A real dataset is used to explain the implementation of the proposed control charts.  相似文献   
9.
媒介发展为大众传播带来巨大变化,影响了收视方式,也影响了观众对电视剧的注意力投入。从传统媒体时代到移动互联网时代,观众的注意力呈现出与收视氛围、收视状态变化相对应的特征变化——投入程度变深,投入时间缩短。观众的注意力从更换率低的、长时间的、无互动性的内容转移到更换频繁的、短时间的、有互动性的、社交式的内容上。在此情境下,电视剧创作必然呈现符合观众与媒介间注意力法则的新趋势——内容长度缩短,情节强度增强,以及对互动性进行一系列探索。  相似文献   
10.
韩国学生中介语各句长句子状语复杂度发展研究   总被引:1,自引:0,他引:1  
通过分析韩国学生中介语句长为6-20个词句子的状语复杂度的发展情况,发现:初、中、高三级中介语各句长句子带状语句子比例、多层状语比例呈逐级上升趋势,多处状语比例和句首状语比例则呈逐级下降趋势;韩国学生中介语表现出句首状语比例超量、多处状语比例突出、多层状语比例不足的特点,在句长一定的前提下,多处状语与多层状语之间可能存在此消彼长的对立互补关系;研究同样发现中介语状语复杂度的发展具有不受教学输入语言制约的特点.  相似文献   
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