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41.
L. J. Ratliff Jr. D. E. Rush Jr. 《Transactions of the American Mathematical Society》2000,352(4):1647-1674
The main theorem characterizes, in terms of bracket powers, analytic spread one ideals in local rings. Specifically, let be regular nonunits in a local (Noetherian) ring and assume that , the integral closure of , where . Then the main result shows that for all but finitely many units in that are non-congruent modulo and for all large integers and it holds that for and not divisible by , where is the -th bracket power of . And, conversely, if there exist positive integers , , and such that has a basis such that , then has analytic spread one.
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43.
根据等效颗粒散射模型,运用经典的Mie理论,对生物组织的散射相函数、各向异性因子及散射系数进行了数值计算.计算结果表明:可见光照射生物组织时,各向异性因子、散射系数随等效颗粒直径增大而增大;等效颗粒直径较小时,各向异性因子、散射系数随入射光波长增大而单调减小;随着等效颗粒直径增大,各向异性因子、散射系数随入射光波长变化不再具有单调性.上述计算结果可合理解释公布的实验结果.
关键词:
生物组织
散射
Mie理论
等效颗粒 相似文献
44.
讨论了振动的振幅与周期的变化规律,给出了当质点质量m0与弹簧质量m之比趋于零与趋于无穷大以及系统水平放置时的振动解. 相似文献
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The stationary random responses of nonlinear shear-type Multi-Degrees-of-Freedom (MDOF) hysteretic system are analyzed by
using the Pseudo Excitation Method (PEM) combined with the Equivalent Linearization Method (ELM). The solution of the equivalent
linear system is obtained by iteratively solving complex algebraic equations instead of the Lyapunov equations. The efficiency
of this method is much higher for practical engineering systems with many degrees-of-freedom.
Supported by NNSFC (Project No. 19772009), NKBRSF fund (No. G1999032805) and Doctoral Funding of State Education Ministry
(No. 97014120). 相似文献
47.
The structural characteristics (the volume fraction, size, and shape of and the distance among hardening-phase particles) of aging alloys and steels, which define the behavior of the critical stress intensity factor during thermal hardening, are determined using the structural-mechanical approach we have developed. It is experimentally demonstrated for maraging steels that our approach is capable of proving the correlations of strength, plasticity, and crack- resistance with the structural characteristics, which were varied by changing the chemical composition of steel and thermokinetic aging conditions__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 1, pp. 94–101, January 2005. 相似文献
48.
Based on composite materials, the equivalent elastic-plastic constitutive equations of multiphase solid are researched. According to the suggested definition of constitutive equivalence it is demonstrated that the multiphase solid, composed of several kinds of homogeneous elastic-plastic media that conform to the generalized normality rule, has the same type of constitutive equations as its constituents have that also conform to the generalized normality rule. 相似文献
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