2 resultados para Accounting standards

em Chinese Academy of Sciences Institutional Repositories Grid Portal


Relevância:

20.00% 20.00%

Publicador:

Resumo:

A three-phase confocal elliptical cylinder model is proposed for fiber-reinforced composites, in terms of which a generalized self-consistent method is developed for fiber-reinforced composites accounting for variations in fiber section shapes and randomness in fiber section orientation. The reasonableness of the fiber distribution function in the present model is shown. The dilute, self-consistent, differential and Mori-Tanaka methods are also extended to consider randomness in fiber section orientation in a statistical sense. A full comparison is made between various micromechanics methods and with the Hashin and Shtrikman's bounds. The present method provides convergent and reasonable results for a full range of variations in fiber section shapes (from circular fibers to ribbons), for a complete spectrum of the fiber volume fraction (from 0 to 1, and the latter limit shows the correct asymptotic behavior in the fully packed case) and for extreme types of the inclusion phases (from voids to rigid inclusions). A very different dependence of the five effective moduli on fiber section shapes is theoretically predicted, and it provides a reasonable explanation on the poor correlation between previous theory and experiment in the case of longitudinal shear modulus.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

利用中国知识资源总库的中国引文数据库检索《水土保持研究》在1994-2006年所载论文的被引用情况,采用文献计量学方法对该刊1994-2006年载文被《中国期刊文献引证数据库》来源期刊引用的情况进行统计分析及评价。从文献引证的角度透视《水土保持研究》的学术水平。该刊1994-2006年共载文2098篇,被引用2018篇,占载文总数的96.62%。2001-2006年该刊影响因子、即年指标等文献计量指标逐年上升,分析表明:《水土保持研究》载文质量较高,在该学科有较大的学术影响力。