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11.
埃德加.斯诺进入苏区后,"红色"在其个人词库中的语义内涵发生了很大转变。这一点直接反映在《红星照耀中国》一书中"红色中国"形象的形成与变化过程上。对这一个案的研究,将充分展现"前理解"和词汇语义弹性在形象建构过程中的复杂作用。  相似文献   
12.
Owing to the extreme quantiles involved, standard control charts are very sensitive to the effects of parameter estimation and non-normality. More general parametric charts have been devised to deal with the latter complication and corrections have been derived to compensate for the estimation step, both under normal and parametric models. The resulting procedures offer a satisfactory solution over a broad range of underlying distributions. However, situations do occur where even such a large model is inadequate and nothing remains but to consider non- parametric charts. In principle, these form ideal solutions, but the problem is that huge sample sizes are required for the estimation step. Otherwise the resulting stochastic error is so large that the chart is very unstable, a disadvantage that seems to outweigh the advantage of avoiding the model error from the parametric case. Here we analyse under what conditions non-parametric charts actually become feasible alternatives for their parametric counterparts. In particular, corrected versions are suggested for which a possible change point is reached at sample sizes that are markedly less huge (but still larger than the customary range). These corrections serve to control the behaviour during in-control (markedly wrong outcomes of the estimates only occur sufficiently rarely). The price for this protection will clearly be some loss of detection power during out-of-control. A change point comes in view as soon as this loss can be made sufficiently small.  相似文献   
13.
论述投资控制的关键环节,提出投资控制工作的实施要点,阐明投资控制工作的必要性、可行性和重大意义.  相似文献   
14.
Summary For technological applications it can be useful to identify some simple physical mechanisms, which, on the basis of the available knowledge of the production process, may suggest the most appropriate approach to statistical control of the random quantities of interest. For this purpose the notion of rupture point is introduced firstly. A rupture point is characterized bym randomly arising out of control states, assumed to be mutually exclusive and stochastically independent. Shewhart's control charts seem to represent the natural statistical tool for controlling a rupture point; however it is shown that they are fully justified only when the hazard rates attached to the causes of failure are constant. Otherwise, typically in the presence of time increasing hazard rates, Shewhart's control charts should be completed by a preventive intervention rule (preventive maintenance). In the second place, the notion of dynamic instability point is introduced, which is specifically characterized by assuming that the random quantity of interest is ruled by a stochastic differential equation with constant coefficients. By discretization, developed according to a possibly new approach, it is shown that the former model reduces to an equation error model, which is among the simplest used in adaptive control, and thus particularly easy to deal with in regard to parameter estimation and the definition of the optimum control rule.  相似文献   
15.
利用上下解,Brouwer不动点原理及Lyapunov泛函方法,讨论了一类具有反馈控制的Logistic扩散系统的周期解问题;获得了周期解存在且稳定的判别条件.  相似文献   
16.
管理行为不同层次的矛盾有其特殊性,可以选择不同的方法加以解决。制度在行为管理手段中有其适用范围,此外,机制、“人制”、自制也是行为管理的另外三种有效手段,这四种行为管理手段有着各自的特点和适用范围,有鉴别地应用好这四种行为管理手段,可以有效地解释行为管理的现象,并可指导行为管理实践。  相似文献   
17.
春秋时的《诗经》是我国最早的一部诗歌总集,其中《关雎》一诗是中外驰名的名诗魁首。对诗中“关关雎鸠”中的“关关”之注释,历来都遵循郑玄的注解。文章从几个方面对此进行考证,发现《诗经》中用象声词模拟鸟鸣叫的句式都和“鸣”字相连;雎鸠无论是那一种鸟,都不可能发出“关关”的叫声;“关关雎鸠”和“淑女采荇”一样,采用的都是比兴的手法。因而认为“关关”是动词重叠连用,说的是先人利用“鸟媒”的一种捕猎方式。这种利用鸟媒的形式表达爱情在民歌中仍得到体现。  相似文献   
18.
本文主要分析了HEIDENHAIN TNC 310数控铣床系统中圆弧铣削指令及螺纹铣削指令,对螺纹铣削功能进行延伸,扩展到圆弧三轴联动,并对螺纹铣削指令格式进行了修改,从而具有圆弧三轴联动铣削功能。  相似文献   
19.
在高校基本建设的投资不断增加的前提下,文章通过4个方面的分析,探讨了有效控制基本建设投资的方法。  相似文献   
20.
Summary.  When evaluating potential interventions for cancer prevention, it is necessary to compare benefits and harms. With new study designs, new statistical approaches may be needed to facilitate this comparison. A case in point arose in a proposed genetic substudy of a randomized trial of tamoxifen versus placebo in asymptomatic women who were at high risk for breast cancer. Although the randomized trial showed that tamoxifen substantially reduced the risk of breast cancer, the harms from tamoxifen were serious and some were life threaten-ing. In hopes of finding a subset of women with inherited risk genes who derive greater bene-fits from tamoxifen, we proposed a nested case–control study to test some trial subjects for various genes and new statistical methods to extrapolate benefits and harms to the general population. An important design question is whether or not the study should target common low penetrance genes. Our calculations show that useful results are only likely with rare high penetrance genes.  相似文献   
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