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21.
一、一号文件出台的背景1.兴水利除水害是治国安邦的头等大事在前不久一次会议上,一位中央领导同志指出,水的问题对中国来讲,历来都是一个大事。党的十五届三中全会决定中也有类似的论述。这次一号文件更是鲜明地提出,水旱  相似文献   
22.
Testing the equality of proportions for correlated otolaryngologic data   总被引:1,自引:0,他引:1  
In otolaryngologic (or ophthalmologic) studies, each subject usually contributes information for each of two ears (or eyes), and the values from the two ears (or eyes) are generally highly correlated. Statistical procedures that fail to take into account the correlation between responses from two ears could lead to incorrect results. On the other hand, asymptotic procedures that overlook small sample designs, sparse data structures, or the discrete nature of data could yield unacceptably high type I error rates even when the intraclass correlation is taken into consideration. In this article, we investigate eight procedures for testing the equality of proportions in such correlated data. These test procedures will be implemented via the asymptotic and approximate unconditional methods. Our empirical results show that tests based on the approximate unconditional method usually produce empirical type I error rates closer to the pre-chosen nominal level than their asymptotic tests. Amongst these, the approximate unconditional score test performs satisfactorily in general situations and is hence recommended. A data set from an otolaryngologic study is used to illustrate our proposed methods.  相似文献   
23.
In this study, we report the results of an investigation into the sintering temperature dependence of magnetic and transport properties for GdBaCo2 O 5 + δ synthesized through a sol-gel method. The lowering of sintering temperature leads to the increase of oxygen content and the reduction of grain size. The increase of oxygen content results in the enhancement of magnetic interactions and the weakening of Coulomb repulsion effect, while the reduction of grain size improves the magnetoresistance effect. Metal-insulator transition accompanied with spin-state transition is observed in all samples.  相似文献   
24.
25.
Yin  Zhaoxia  Abel  Andrew  Tang  Jin  Zhang  Xinpeng  Luo  Bin 《Multimedia Tools and Applications》2017,76(3):3899-3920
Multimedia Tools and Applications - In recent years there has been significant interest in reversible data hiding, and also in particular, reversible data hiding in encrypted images (RDH-EI). This...  相似文献   
26.
Structural and Multidisciplinary Optimization - The ubiquitous uncertainties presented in the input factors (e.g., material properties and loads) commonly lead to occasional failure of mechanical...  相似文献   
27.
Re-engineering of the design process for concurrent engineering   总被引:20,自引:0,他引:20  
According to the requirements of concurrent engineering, three interdependency relationships (uncoupled relationship, coupled relationship and decoupled relationship) between design activities are presented in this paper. And the coupled relationship plays an important role in concurrent product design process. To represent the precedence relationships among design activities, a directed graph is used to describe the design process. And the interdependency relationship between activities is illustrated by a Design Structure Matrix which is the transpose of the accessibility matrix of the corresponding graph. Using the DSM, an algorithm of recognizing the coupled activities during the design process is presented. Moreover, an algorithm to figure out the order levels of activities during the design process is proposed. And both algorithms are illustrated with a die design example.  相似文献   
28.
阐述了实验室教学管理服务器的规划方法,并总结了服务器系统在安装设置和管理中的一些主要安全策略。  相似文献   
29.
转炉炼钢脱氧工艺的优化   总被引:1,自引:0,他引:1  
论述了转炉炼钢脱氧工艺优化的原理,并结合实际对脱氧剂使用工艺进行了探索,成功地在炼钢生产中推广应用.  相似文献   
30.
In recent years much effort has been devoted to the quantum mechanically corrected Monte Carlo simulation of nano-scale semiconductor devices. The effective potential and the Wigner or the Bohm quantum potential are usually chosen for making such quantum correction. In this study we propose another approach based on the Bohm potential by transforming the density gradient to an effective conduction-band edge gradient. Similar to the effective potential method, this method has the advantage of not being affected by density fluctuations. We have applied this method to the simulation of a double-gate nMOSFET. Results are compared to those obtained from the semi-classical Monte Carlo simulation without the quantum correction.  相似文献   
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