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991.
提出了二元极值分布的一个独立性检验统计量 T5,导出了它的渐近分布 ,得出了模拟分位点 ,并在小样本情况下 ,与其它已有的统计量进行比较 .结果说明本文给出的统计量 T5具有与似然比检验统计量 T3几乎相同的功效 ,且比其它检验方法有效 .最后对中国沪深两市的股票收盘指数的极值进行了独立性检验 ,认为具有显著的相关性 . 相似文献
992.
J. H. Petropoulos K. G. Papadokostaki S. G. Amarantos 《Journal of Polymer Science.Polymer Physics》1992,30(7):717-725
A theoretical model, which takes proper account of the simultaneous uptake of a liquid leachant by a polymer matrix and the consequent release of a bioactive or other solute incorporated therein, is presented and the kinetics of release predicted under various conditions is investigated. This model is shown to be both more rigorous and much more widely applicable than previous attempts to approach the above problem. Furthermore, it can be easily modified or extended, in accordance with the information available about any particular system. It is, therefore, expected that the model introduced here will prove useful as a basis for the design of monolithic controlled-release devices of this type or for the evaluation of the leachability of low-level and medium-level radioactive wastes “immobilized” in polymeric matrices. 相似文献
993.
WU Bo YUAN Song-YueChangchun Institute of Applied Chemistry Academia Sinica Changchun .Jilin YU Zuo-LongChengdu Institute of Organic Chemistry Acadernia Sinica Chengdu Xichuan To whom correspondence should be addressed. 《天然气化学杂志》1995,(1)
CO2TPD was used to study the surface basicity of La-Me-O mixed oxides and O2-TPD was employed to study the surface active oxygen species. Among numerous catalysts studied , La Ba O (La/Ba=7/3) catalyst had the strongest basicity, and gave the highest CH4 conversion and C2 selectivity. 相似文献
994.
Wu Xue-bing 《Frontiers of Physics in China》2006,1(2):135-142
The determination of the mass of black holes in our universe is crucial to understand their physics nature but is a great
challenge to scientists. In this paper I briefly review some methods that are currently used to estimate the mass of black
holes, especially those in X-ray binary systems and in galactic nuclei. Our recent progress in improving the mass estimates
of supermassive black holes in active galactic nuclei by involving some empirical relations is presented. Finally I point
out the similarities and common physics in Galactic black hole X-ray binaries and active galactic nuclei, and demonstrate
that the black hole mass estimation is very much helpful to understand the accretion physics around black holes. 相似文献
995.
Takahiro Uno Masaya Minari Masataka Kubo Takahito Itoh 《Journal of polymer science. Part A, Polymer chemistry》2004,42(18):4548-4555
Asymmetric anionic polymerizations of 2,6-dimethyl-7-phenyl-1,4-benzoquinone methide ( 1 ) were performed with various chiral anionic initiators, and the specific rotations of the obtained polymers were investigated. Optically active poly( 1 )s with configurational chirality were obtained with all the initiators, and a complex of fluorenyllithium (FlLi) with (−)-sparteine [(−)-Sp] produced poly( 1 ) with the largest negative specific rotation ([α]435 = −26.8°). The specific rotations of poly( 1 )s obtained with FlLi/(−)-Sp depended on the initiator concentration and the solvent polarity. The maximum specific rotations were obtained at an almost constant initiator concentration (ca. 0.03 mol/L), regardless of the monomer concentration, in toluene, whereas a higher initiator concentration was required in more polar solvents. These results suggested that the aggregation state of the propagating chain end significantly affected the specific rotation of poly( 1 ). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4548–4555, 2004 相似文献
996.
控制图判断准则的显著性检验 总被引:2,自引:0,他引:2
徐哲,段晓江.控制图判断准则的显著性检验.数理统计与管理,1998,17(3),45~48.利用控制图判断生产过程的状态是一种统计判断,必然犯两种错误。本文在规定“小概率事件”标准的基础上,对休哈特控制图判断准则假设检验的显著性水平进行了分析,并直观解释了各种异常情况的系统性变化特点,最后简述了计算机辅助质量控制图的应用 相似文献
997.
结构噪声是超声脉冲在介质结构上激发产生的一种特殊噪声,它严重妨碍超声检测,是超声检测的基本限制因素之一;但也可被利用进行某些检测。本文综述了有关结构噪声的基本研究,抑制或降低结构噪声的方法,以及在结构噪声背景下进行超声检测和利用结构噪声进行超声检测的有关工作。 相似文献
998.
The problem of dependency between two random variables has been studied throughly in the literature. Many dependency measures have been proposed according to concepts such as concordance, quadrant dependency, etc. More recently, the development of the Theory of Copulas has had a great impact in the study of dependence of random variables specially in the case of continuous random variables. In the case of the multivariate setting, the study of the strong mixing conditions has lead to interesting results that extend some results like the central limit theorem to the case of dependent random variables.In this paper, we study the behavior of a multidimensional extension of two well-known dependency measures, finding their basic properties as well as several examples. The main difference between these measures and others previously proposed is that these ones are based on the definition of independence among n random elements or variables, therefore they provide a nice way to measure dependency.The main purpose of this paper is to present a sample version of one of these measures, find its properties, and based on this sample version to propose a test of independence of multivariate observations. We include several references of applications in Statistics. 相似文献
999.
1000.