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21.
Within the framework of a piecewise homogeneous body model, with the use of three-dimensional geometrically nonlinear exact equations of elasticity theory, a method for determining the stress—strain state in unidirectional fibrous composites with locally curved fibers is developed for the case where the interaction between the fibers is neglected. All the investigations are carried out for an infinite elastic body containing a single locally curved fiber. Numerical results illustrating the effect of geometrical nonlinearity on the distribution of the self-balanced normal and shear stresses acting on the interface and arising as a result of local curving of the fiber are presented.__________Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 41, No. 4, pp. 433–448, July–August, 2005. 相似文献
22.
23.
Non-isothermal short-range-order kinetics of binary alloys as influenced by solute-vacancy complexes
A model describing the roles of bound and unbound vacancies is proposed in order to predict defect decay and short-range-order
kinetics of quenched binary alloys during linear heating experiments. This is an alternative treatment of a previous approach.
The model has been applied to the differential scanning calorimetry (DSC) curves of Cu-5 at.% Zn quenched from different temperatures.
An expression to calculate the activation energy for migration of solute-vacancy complexes was also developed which make use
of DSC trace data. A value of 89.12±0.32 kJ mol-1 was obtained for the above alloy. The relative contribution of bound and unbound vacancies to partition of effective activation
energy corresponding to the ordering process as influenced by quenching temperature was also assessed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
24.
新建地方院校实验室仪器设备管理工作探讨 总被引:1,自引:0,他引:1
张勇 《科技情报开发与经济》2007,17(34):231-232
分析了新建地方院校实验室仪器设备管理工作的特点和问题,探讨了加强仪器设备管理的措施。 相似文献
25.
武小茹 《科技情报开发与经济》2007,17(19):42-43
介绍了公共图书馆地方文献的收藏特色,论述了树立地方文献品牌的途径,提出了全面开发地方文献资源的建议。 相似文献
26.
In basin modelling the thermodynamics of a multicomponent multiphase fluid flux are computationally too expensive when derived from an equation of state and the Gibbs equality constraints. In this article we present a novel implicit molar mass formulation technique using binary mixture thermodynamics. The two proposed solution methods, with and without cross derivative terms between components, are based on a preconditioned Newton‐GMRES scheme for each time‐step with analytical computation of the derivatives. These new algorithms reduce significantly the numerical effort for the computation of the molar masses, and we illustrate the behavior of these methods with numerical computations. Copyright © 2004 John Wiley & Sons Ltd. 相似文献
27.
Shea-Ming Oon 《Periodica Mathematica Hungarica》2004,49(2):107-118
In this paper we study some pseudo-random properties related to the prime factors of integers. We prove some results concerning the well distribution of the greatest prime factor modulo 4, and give some computational insight on the correlations, which seem to be beyond reach of proof. 相似文献
28.
张少伟 《武汉科技大学学报(自然科学版)》1992,(4)
本文以 Born-Harb 循环为依据,推导了复合晶体晶格能和与其相应的各二元化合物晶体晶格能之间的关系,并由此给出了复合氧化物晶体晶格能近似计算的新公式。对20种复合氧化物晶体晶格能计算结果的分析表明:用本文所给公式对复合氧化物晶体晶格能进行近似计算是可行的。 相似文献
29.
Hidetoshi Shimodaira 《Annals of the Institute of Statistical Mathematics》1997,49(3):395-410
The asymptotic error probability of Linhart's model selection test isevaluated, and compared with the nominal significance level. We examine thecase where the expected discrepancies of the candidate models from the truemodel are asymptotically equal. The local alternatives method is employed inthe limiting operation of the asymptotic evaluation. Although the errorprobability under the null hypothesis is actually shown to be equal to orless than the level for most situations, intolerable violations of the errorcontrol are observed for nested models: It is often erroneously concludedthat the smaller model is significantly better than the larger model. Toprevent this violation, a modification of Linhart's test statistic isproposed. The effectiveness of the proposed test is confirmed throughtheoretical analysis and numerical simulations. 相似文献
30.
数字散斑干涉技术在振动分析中的应用 总被引:2,自引:0,他引:2
首次将相移技术应用于频闪数字散斑干涉计量中,对物体的振动进行了定量分析.实验证明,这种方法有广泛的实用价值.另外,介绍了一套自动分析系统,讨论了各参数对测量结果的影响. 相似文献