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991.
992.
§ 1 IntroductionThere are many discussions on the estimate of density,for example,the kernel andnearest neighbor estimates.Reference [1 ] gave the nearest neighbor-kernel estimate ofconditional density.[2 ] discussed the properties on the nearest neighbor-kernel estimateand bootstrap approximation of conditional density.[3 ] studied some asymptotical proper-ties on kernel estimate and random weighting approximation of density.In this paper,wewill discuss the properties of the nearest neighb… 相似文献
993.
Novel phenolic resins with high ethynyl contents were realized via azo coupling reaction between phenol units and diazonium of 3-ethynylaniline. If Novolac and high-ortho Novolac resins were used as the starting materials directly, the ratio of ethynyl groups to phenolic rings was ca 70%; while the ratio was 100% for the resin from Friedel-Craft polycondensation of 4-(3-ethynylphenyl)salicyl alcohol. All the resins were readily soluble in acetone and ethanol, and meltable at temperatures below 100 °C. The resins underwent thermal addition-type cure with a broad exotherm of around 140-280 °C, and the starting curing temperature showed a downward drift with increase in the ethynyl content. The thermal properties of the cured resins, determined from thermogravimetric analysis (TGA), were considerably superior to those of Novolac- and Resole-type phenolic resins. The initial decomposition temperatures were at ca 400 °C, and the anaerobic carbon yields were ca 80% for all the resins. 相似文献
994.
Li Hong Xiao Cheng Liu Xi Gao Jian 《中国化学快报》2008,19(2):227-229
A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were between 38,330 and 67,900. The glass transition temperatures (Tg) and 5% decomposition temperatures were ranged in 253-269 ℃ and 488-500 ℃, respectively, The structures of these copolymers were confirmed by FT-IR and ^1H NMR. Moreover, all the resultant copolymers were amorphous determined by wide angle X-ray diffraction (WAXD). 相似文献
995.
996.
Robert J. Boik 《Annals of the Institute of Statistical Mathematics》2008,60(1):61-83
A linear model in which random errors are distributed independently and identically according to an arbitrary continuous distribution
is assumed. Second- and third-order accurate confidence intervals for regression parameters are constructed from Charlier
differential series expansions of approximately pivotal quantities around Student’s t distribution. Simulation verifies that small sample performance of the intervals surpasses that of conventional asymptotic
intervals and equals or surpasses that of bootstrap percentile-t and bootstrap percentile-|t| intervals under mild to marked departure from normality. 相似文献
997.
Error bounds for asymptotic expansions of the distribution of the MLE in a GMANOVA model 总被引:1,自引:0,他引:1
Yasunori Fujikoshi 《Annals of the Institute of Statistical Mathematics》1987,39(1):153-161
Summary In this paper we obtain asymptotic expansions for the distribution function and the density function of a linear combination
of the MLE in a GMANOVA model, and for the density function of the MLE itself. We also obtain certain error bounds for the
asymptotic expansions. 相似文献
998.
Xiao Qian WANG Shi Hong CHENG 《数学学报(英文版)》2005,21(5):1121-1130
In Part Ⅰ the concept of the general regular variation of n-th order is proposed and its construction is discussed. The uniqueness of the standard expression and the higher order regularity of the auxiliary functions are proved. 相似文献
999.
1000.
A formula expressing the statistical entropy of a lattice-gas model as a multiparticle correlation expansion is derived in the grand-canonical and in the canonical ensembles. The differences from the analogous expansion in the continuum case are elucidated. The Ising model in one dimension is discussed as a case study. 相似文献